From a78dba7a5aa7268b4b64c8067457e5a1104188ad Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Robert=20Soul=C3=A9?= Date: Tue, 16 May 2017 11:38:27 -0700 Subject: [PATCH] This commit includes example tutorials and solutions for P4D2 2017. (#29) - Added example P4 programs for ipv4_forwarding, mri, arp, calc - Added python code to invoke compiler, start bmv2, run mininet - Added solutions to above programs - Added README files that describe exercises --- P4D2_2017/exercises/README.md | 63 ++++ P4D2_2017/exercises/arp/README.md | 174 ++++++++++ P4D2_2017/exercises/arp/arp.p4 | 232 +++++++++++++ P4D2_2017/exercises/arp/p4app.json | 10 + P4D2_2017/exercises/arp/run.sh | 5 + P4D2_2017/exercises/arp/simple_router.config | 1 + P4D2_2017/exercises/arp/solution/arp.p4 | 305 +++++++++++++++++ P4D2_2017/exercises/calc/README.md | 115 +++++++ P4D2_2017/exercises/calc/calc.p4 | 127 +++++++ P4D2_2017/exercises/calc/calc.py | 95 ++++++ P4D2_2017/exercises/calc/p4app.json | 10 + P4D2_2017/exercises/calc/run.sh | 5 + P4D2_2017/exercises/calc/simple_router.config | 0 P4D2_2017/exercises/calc/solution/calc.p4 | 263 ++++++++++++++ P4D2_2017/exercises/ipv4_forward/README.md | 156 +++++++++ .../exercises/ipv4_forward/ipv4_forward.p4 | 170 ++++++++++ P4D2_2017/exercises/ipv4_forward/p4app.json | 33 ++ P4D2_2017/exercises/ipv4_forward/receive.py | 50 +++ P4D2_2017/exercises/ipv4_forward/run.sh | 5 + .../exercises/ipv4_forward/s1-commands.txt | 4 + .../exercises/ipv4_forward/s2-commands.txt | 4 + .../exercises/ipv4_forward/s3-commands.txt | 4 + P4D2_2017/exercises/ipv4_forward/send.py | 40 +++ .../ipv4_forward/solution/ipv4_forward.p4 | 180 ++++++++++ P4D2_2017/exercises/mri/README.md | 206 +++++++++++ P4D2_2017/exercises/mri/mri.p4 | 286 ++++++++++++++++ P4D2_2017/exercises/mri/p4app.json | 33 ++ P4D2_2017/exercises/mri/receive.py | 50 +++ P4D2_2017/exercises/mri/run.sh | 5 + P4D2_2017/exercises/mri/s1-commands.txt | 5 + P4D2_2017/exercises/mri/s2-commands.txt | 5 + P4D2_2017/exercises/mri/s3-commands.txt | 5 + P4D2_2017/exercises/mri/send.py | 58 ++++ P4D2_2017/exercises/mri/solution/mri.p4 | 278 +++++++++++++++ P4D2_2017/utils/mininet/appcontroller.py | 103 ++++++ P4D2_2017/utils/mininet/apptopo.py | 69 ++++ .../utils/mininet/multi_switch_mininet.py | 242 +++++++++++++ P4D2_2017/utils/mininet/p4_mininet.py | 161 +++++++++ P4D2_2017/utils/mininet/shortest_path.py | 78 +++++ .../utils/mininet/single_switch_mininet.py | 133 ++++++++ P4D2_2017/utils/p4apprunner.py | 320 ++++++++++++++++++ 41 files changed, 4088 insertions(+) create mode 100644 P4D2_2017/exercises/README.md create mode 100644 P4D2_2017/exercises/arp/README.md create mode 100644 P4D2_2017/exercises/arp/arp.p4 create mode 100644 P4D2_2017/exercises/arp/p4app.json create mode 100755 P4D2_2017/exercises/arp/run.sh create mode 100644 P4D2_2017/exercises/arp/simple_router.config create mode 100644 P4D2_2017/exercises/arp/solution/arp.p4 create mode 100644 P4D2_2017/exercises/calc/README.md create mode 100644 P4D2_2017/exercises/calc/calc.p4 create mode 100755 P4D2_2017/exercises/calc/calc.py create mode 100644 P4D2_2017/exercises/calc/p4app.json create mode 100755 P4D2_2017/exercises/calc/run.sh create mode 100644 P4D2_2017/exercises/calc/simple_router.config create mode 100644 P4D2_2017/exercises/calc/solution/calc.p4 create mode 100644 P4D2_2017/exercises/ipv4_forward/README.md create mode 100644 P4D2_2017/exercises/ipv4_forward/ipv4_forward.p4 create mode 100644 P4D2_2017/exercises/ipv4_forward/p4app.json create mode 100755 P4D2_2017/exercises/ipv4_forward/receive.py create mode 100755 P4D2_2017/exercises/ipv4_forward/run.sh create mode 100644 P4D2_2017/exercises/ipv4_forward/s1-commands.txt create mode 100644 P4D2_2017/exercises/ipv4_forward/s2-commands.txt create mode 100644 P4D2_2017/exercises/ipv4_forward/s3-commands.txt create mode 100755 P4D2_2017/exercises/ipv4_forward/send.py create mode 100644 P4D2_2017/exercises/ipv4_forward/solution/ipv4_forward.p4 create mode 100644 P4D2_2017/exercises/mri/README.md create mode 100644 P4D2_2017/exercises/mri/mri.p4 create mode 100644 P4D2_2017/exercises/mri/p4app.json create mode 100755 P4D2_2017/exercises/mri/receive.py create mode 100755 P4D2_2017/exercises/mri/run.sh create mode 100644 P4D2_2017/exercises/mri/s1-commands.txt create mode 100644 P4D2_2017/exercises/mri/s2-commands.txt create mode 100644 P4D2_2017/exercises/mri/s3-commands.txt create mode 100755 P4D2_2017/exercises/mri/send.py create mode 100644 P4D2_2017/exercises/mri/solution/mri.p4 create mode 100644 P4D2_2017/utils/mininet/appcontroller.py create mode 100644 P4D2_2017/utils/mininet/apptopo.py create mode 100755 P4D2_2017/utils/mininet/multi_switch_mininet.py create mode 100644 P4D2_2017/utils/mininet/p4_mininet.py create mode 100644 P4D2_2017/utils/mininet/shortest_path.py create mode 100755 P4D2_2017/utils/mininet/single_switch_mininet.py create mode 100755 P4D2_2017/utils/p4apprunner.py diff --git a/P4D2_2017/exercises/README.md b/P4D2_2017/exercises/README.md new file mode 100644 index 0000000..32a8f16 --- /dev/null +++ b/P4D2_2017/exercises/README.md @@ -0,0 +1,63 @@ +# P4 Tutorial + +## Introduction + +Welcome to the P4 Tutorial! + +We've prepared a set of four exercises that will help you get started +with P4 programming: + +1. [L3 forwarding](./ipv4_forward) + +2. [Multi-Hop Route Inspection](./mri) + +3. [ARP/ICMP Responder](./arp) + +4. [Calculator](./calc) + +## Obtaining required software + +If you are starting this tutorial as part of the P4 Developer Day, then +we've already provided you with a virtual machine that has all of the +required software installed. + +Otherwise, to complete the exercises, you will need to clone two p4lang Github repositories +and install their dependencies. To clonde the repositories: + +- `git clone https://github.com/p4lang/behavioral-model.git bmv2` +- `git clone https://github.com/p4lang/p4c-bm.git p4c-bmv2` + +The first repository ([bmv2](https://github.com/p4lang/behavioral-model)) is the +second version of the behavioral model. It is a C++ software switch that will +behave according to your P4 program. The second repository +([p4c-bmv2](https://github.com/p4lang/p4c-bm)) is the compiler for the +behavioral model: it takes P4 program and output a JSON file which can be loaded +by the behavioral model. + +Each of these repositories come with dependencies. `p4c-bmv2` is a Python +repository and installing the required Python dependencies is very easy to do +using `pip`: `sudo pip install -r requirements.txt`. + +`bmv2` is a C++ repository and has more external dependencies. They are listed +in the +[README](https://github.com/p4lang/behavioral-model/blob/master/README.md). If +you are running Ubuntu 14.04+, the dependencies should be easy to install (you +can use the `install_deps.sh` script that comes with `bmv2`). Do not forget to +build the code once all the dependencies have been installed: + +``` +$ ./autogen.sh +$ ./configure +$ make +``` + + +You will also need to install `mininet`, as well as the following Python +packages: `scapy`, `thrift` (>= 0.9.2) and `networkx`. On Ubuntu, it would look +like this: + +``` +$ sudo apt-get install mininet +$ sudo pip install scapy thrift networkx +``` + diff --git a/P4D2_2017/exercises/arp/README.md b/P4D2_2017/exercises/arp/README.md new file mode 100644 index 0000000..1a71dac --- /dev/null +++ b/P4D2_2017/exercises/arp/README.md @@ -0,0 +1,174 @@ +# Implementing an ARP/ICMP Responder + +## Introduction + +This exercise extends the [IPv4 Forwarding](../ipv4_forward) program to +allow your switches to respond to ARP and ICMP requests. Once implemented, +your hosts will be able to `ping` other hosts connected to the switch, and +have the switch respond. + +This exercise makes several simplifying assumptions: + +1. The network topology contains exactly one switch and two hosts. +1. ARP and ICMP requests to the hosts are ignored; only requests sent to the + switch receive responses. + +Implementing the full functionality of ARP and ICMP is straightforward but +beyond the scope of this tutorial and left as an exercise to the reader. + +> **Spoiler alert:** There is a reference solution in the `solution` +> sub-directory. Feel free to compare your implementation to the reference. + +## Step 1: Run the (incomplete) starter code + +The directory with this README also contains a skeleton P4 program, +`arp.p4`, which initially drops all packets. Your job will be to +extend it to reply to ARP and ICMP requests. + +As a first step, compile the incomplete `arp.p4` and bring up a +switch in Mininet to test its behavior. + +1. In your shell, run: + ```bash + ./run.sh + ``` + This will: + * compile `arp.p4`, and + * start a Mininet instance with one switch (`s1`) connected to two hosts (`h1`, `h2`). + * The hosts are assigned IPs of `10.0.1.10` and `10.0.2.10`. + +2. Once the P4 source compiles without error, you can test your program at the +mininet prompt using the `ping` utility. + + ``` mininet> h1 ping h2 ``` + + Once the program is implemented correctly, you will see a response to the + ping in the mininet window. + +3. Type `exit` in the mininet terminal to exit. + + +### A note about the control plane + +P4 programs define a packet-processing pipeline, but the rules governing packet +processing are inserted into the pipeline by the control plane. When a rule +matches a packet, its action is invoked with parameters supplied by the control +plane as part of the rule. + +In this exercise, the control plane logic has already been implemented. As +part of bringing up the Mininet instance, the `run.sh` script will install +packet-processing rules in the tables of each switch. These are defined in the +`simple_router.config` file. + + +## Step 2: Implement ARP/ICMP Replies + +In this exercise, we are using entries in the `ipv4_lpm` table as a +database, which we can reference when responding to ARP and ICMP requests. +Without the proper entries in the table, the solution will not work. + +From a high-level, the task involves implementing two main components: ARP +replies and ICMP replies. + +### ARP Reply + +When the switch receives and ARP request asking to resolve the switch's IP +address, it will need to perform the following actions: + +1. Swap the source and destination MAC addresses in the Ethernet header, +1. set the ARP operation to ARP_REPLY (`2`) in the ARP header, +1. update the sender hardware address (SHA) and sender protocol address (SPA) in the ARP header to +be the MAC and IP addresses of the switch, and +1. set the target hardware address (THA) and target protocol address (TPA) to be the SHA +and SPA of the arriving ARP packet. + +### ICMP Reply + +When the switch receives and ICMP request containing the switch's IP and MAC +addresses, it will need to perform the following actions: + +1. Swap the source and destination MAC addresses in the Ethernet header, +1. swap the source and destination IP addresses in the ICMP header, and +1. set the type field in the ICMP header to `ICMP_ECHO_REPLY` (`0`). +1. To simplify the exercise, we can ignore the checksum by setting to checksum + field to 0. + + +We have provided a skeleton `arp.p4` file to get you started. In this +file, places to modify are marked by `TODO`. + +There are, of course, different possible solutions. We describe one approach +below. It builds on the [IPv4 Forwarding](../ipv4_forward) solution, which +used the table `ipv4_lpm` for L3 forwarding, by adding a second table named +`forward`, which checks if a packet is an ARP or ICMP packet and invokes +actions to send an ARP reply, forward an IPv4 packet, or send an ICMP reply. + +Broadly speaking, a complete solution will contain the following components: + +1. Header type definitions for `ethernet_t`, `arp_t`, `ipv4_t`, and `icmp_t`. + +1. A structure (named `my_metadata_t` in `arp.p4`) with metadata fields for the +packet's souce and destination MAC addresses, IPv4 address, egress port, as +well as a hard-coded MAC address for the switch. + +1. **TODO:** Parsers for Ethernet, ARP, IPv4, and ICMP packet header types. + +1. **TODO:** A control type declaration for ingress processing, containing: + + 1. An action for `drop`. + + 1. An action (named `ipv4_forward`) to store information in the metadata + structure, rather than immediately writing to the packet header. + + 1. A table (named `ipv4_lpm`) that will match on the destination IP address + and invoke the `ipv4_forward` action. + + 1. An action to send an ICMP reply. + + 1. An action to send an ARP reply. + + 1. A table (named `forward`) that will forward IPv4 packets, send an ARP + reply, send an ICMP reply, or drop a packet. + + 1. An `apply` block that implements the control logic to invoke the two + tables. + +1. A deparser that emits headers in the proper order. + +To keep the exercise simple, we will ignore the `ipv4_checksum`. You should not +need any control plane rules for this exercise. + +## Step 3: Run your solution + +Follow the instructions from Step 1. This time, you should be able to +successfully `ping` the switch. + +### Troubleshooting + +There are several ways that problems might manifest: + +1. `arp.p4` fails to compile. In this case, `run.sh` will report the +error emitted from the compiler and stop. + +1. `arp.p4` compiles, but the switch does not process packets in the desired +way. The `build/logs/.log` files contain trace messages +describing how each switch processes each packet. The output is detailed and +can help pinpoint logic errors in your implementation. + +> Note that there are no control plane rules installed in this example, and so +> the `receive.py` and `send.py` scripts from the [IPv4 +> Forwarding](../ipv4_forward) example will not work. + +#### Cleaning up Mininet + +In the latter case above, `run.sh` may leave a Mininet instance running in +the background. Use the following command to clean up these instances: + +```bash +mn -c +``` + +## Next Steps + +Congratulations, your implementation works! Move on to the next exercise: +turning your switch into a [Calculator](../calc). diff --git a/P4D2_2017/exercises/arp/arp.p4 b/P4D2_2017/exercises/arp/arp.p4 new file mode 100644 index 0000000..5c80530 --- /dev/null +++ b/P4D2_2017/exercises/arp/arp.p4 @@ -0,0 +1,232 @@ +/* -*- P4_16 -*- */ + +#include +#include + +/************************************************************************* + *********************** C O N S T A N T S ***************************** + *************************************************************************/ + /* Define the useful global constants for your program */ +const bit<16> ETHERTYPE_IPV4 = 0x0800; +const bit<16> ETHERTYPE_ARP = 0x0806; +const bit<8> IPPROTO_ICMP = 0x01; + +/************************************************************************* + *********************** H E A D E R S ********************************* + *************************************************************************/ + /* Define the headers the program will recognize */ + +/* + * Standard ethernet header + */ +typedef bit<48> mac_addr_t; +typedef bit<32> ipv4_addr_t; +typedef bit<9> port_id_t; + +header ethernet_t { + mac_addr_t dstAddr; + mac_addr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ipv4_addr_t srcAddr; + ipv4_addr_t dstAddr; +} + +const bit<16> ARP_HTYPE_ETHERNET = 0x0001; +const bit<16> ARP_PTYPE_IPV4 = 0x0800; +const bit<8> ARP_HLEN_ETHERNET = 6; +const bit<8> ARP_PLEN_IPV4 = 4; +const bit<16> ARP_OPER_REQUEST = 1; +const bit<16> ARP_OPER_REPLY = 2; + +header arp_t { + bit<16> htype; + bit<16> ptype; + bit<8> hlen; + bit<8> plen; + bit<16> oper; +} + +header arp_ipv4_t { + mac_addr_t sha; + ipv4_addr_t spa; + mac_addr_t tha; + ipv4_addr_t tpa; +} + +const bit<8> ICMP_ECHO_REQUEST = 8; +const bit<8> ICMP_ECHO_REPLY = 0; + +header icmp_t { + bit<8> type; + bit<8> code; + bit<16> checksum; +} + +/* Assemble headers in a single struct */ +struct my_headers_t { + ethernet_t ethernet; + arp_t arp; + arp_ipv4_t arp_ipv4; + ipv4_t ipv4; + icmp_t icmp; +} + +/************************************************************************* + *********************** M E T A D A T A ******************************* + *************************************************************************/ + /* Define the global metadata for your program */ + +struct my_metadata_t { + ipv4_addr_t dst_ipv4; + mac_addr_t mac_da; + mac_addr_t mac_sa; + port_id_t egress_port; + mac_addr_t my_mac; +} + +/************************************************************************* + *********************** P A R S E R *********************************** + *************************************************************************/ +parser MyParser( + packet_in packet, + out my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + state start { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + ETHERTYPE_IPV4 : parse_ipv4; + ETHERTYPE_ARP : parse_arp; + default : accept; + } + } + + state parse_arp { + /* + * TODO: parse ARP. If the ARP protocol field is + * IPV4, transtion to parse_arp_ipv4 + */ + transition accept; + } + + state parse_arp_ipv4 { + /* + * TODO: parse ARP_IPV4. Hint: one + * possible solution is to store the + * target packet address in a meta data + * field when parsing. + */ + transition accept; + } + + state parse_ipv4 { + packet.extract(hdr.ipv4); + meta.dst_ipv4 = hdr.ipv4.dstAddr; + transition select(hdr.ipv4.protocol) { + IPPROTO_ICMP : parse_icmp; + default : accept; + } + } + + state parse_icmp { + /* TODO: parse ICMP */ + transition accept; + } +} + +/************************************************************************* + ************ C H E C K S U M V E R I F I C A T I O N ************* + *************************************************************************/ +control MyVerifyChecksum( + in my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { } +} + +/************************************************************************* + ************** I N G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyIngress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + action drop() { + mark_to_drop(); + exit; + } + + /* TODO: Define actions and tables here */ + + + table ipv4_lpm { + key = { meta.dst_ipv4 : lpm; } + actions = { /* TODO: add actions */ drop; } + default_action = drop(); + } + + + apply { + meta.my_mac = 0x000102030405; + ipv4_lpm.apply(); + /* TODO: add contol logic */ + } +} + +/************************************************************************* + **************** E G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyEgress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* + ************* C H E C K S U M C O M P U T A T I O N ************** + *************************************************************************/ +control MyComputeChecksum( + inout my_headers_t hdr, + inout my_metadata_t meta) +{ + + apply { } +} + + +/************************************************************************* + *********************** D E P A R S E R ******************************* + *************************************************************************/ +control MyDeparser( + packet_out packet, + in my_headers_t hdr) +{ + apply { + /* TODO: Implement deparser */ + } +} + +V1Switch( + MyParser(), + MyVerifyChecksum(), + MyIngress(), + MyEgress(), + MyComputeChecksum(), + MyDeparser() +) main; diff --git a/P4D2_2017/exercises/arp/p4app.json b/P4D2_2017/exercises/arp/p4app.json new file mode 100644 index 0000000..8579ccd --- /dev/null +++ b/P4D2_2017/exercises/arp/p4app.json @@ -0,0 +1,10 @@ +{ + "program": "arp.p4", + "language": "p4-16", + "targets": { + "mininet": { + "num-hosts": 2, + "switch-config": "simple_router.config" + } + } +} diff --git a/P4D2_2017/exercises/arp/run.sh b/P4D2_2017/exercises/arp/run.sh new file mode 100755 index 0000000..d5c1947 --- /dev/null +++ b/P4D2_2017/exercises/arp/run.sh @@ -0,0 +1,5 @@ +P4APPRUNNER=../../utils/p4apprunner.py +mkdir -p build +tar -czf build/p4app.tgz * --exclude='build' +#cd build +sudo python $P4APPRUNNER p4app.tgz --build-dir ./build diff --git a/P4D2_2017/exercises/arp/simple_router.config b/P4D2_2017/exercises/arp/simple_router.config new file mode 100644 index 0000000..0229c8d --- /dev/null +++ b/P4D2_2017/exercises/arp/simple_router.config @@ -0,0 +1 @@ +table_add ipv4_lpm set_dst_info 10.0.1.10/24 => 00:00:01:00:00:01 00:00:02:00:00:02 1 diff --git a/P4D2_2017/exercises/arp/solution/arp.p4 b/P4D2_2017/exercises/arp/solution/arp.p4 new file mode 100644 index 0000000..69065e6 --- /dev/null +++ b/P4D2_2017/exercises/arp/solution/arp.p4 @@ -0,0 +1,305 @@ +/* -*- P4_16 -*- */ + +#include +#include + +/************************************************************************* + *********************** C O N S T A N T S ***************************** + *************************************************************************/ + /* Define the useful global constants for your program */ +const bit<16> ETHERTYPE_IPV4 = 0x0800; +const bit<16> ETHERTYPE_ARP = 0x0806; +const bit<8> IPPROTO_ICMP = 0x01; + +/************************************************************************* + *********************** H E A D E R S ********************************* + *************************************************************************/ + /* Define the headers the program will recognize */ + +/* + * Standard ethernet header + */ +typedef bit<48> mac_addr_t; +typedef bit<32> ipv4_addr_t; +typedef bit<9> port_id_t; + +header ethernet_t { + mac_addr_t dstAddr; + mac_addr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ipv4_addr_t srcAddr; + ipv4_addr_t dstAddr; +} + +const bit<16> ARP_HTYPE_ETHERNET = 0x0001; +const bit<16> ARP_PTYPE_IPV4 = 0x0800; +const bit<8> ARP_HLEN_ETHERNET = 6; +const bit<8> ARP_PLEN_IPV4 = 4; +const bit<16> ARP_OPER_REQUEST = 1; +const bit<16> ARP_OPER_REPLY = 2; + +header arp_t { + bit<16> htype; + bit<16> ptype; + bit<8> hlen; + bit<8> plen; + bit<16> oper; +} + +header arp_ipv4_t { + mac_addr_t sha; + ipv4_addr_t spa; + mac_addr_t tha; + ipv4_addr_t tpa; +} + +const bit<8> ICMP_ECHO_REQUEST = 8; +const bit<8> ICMP_ECHO_REPLY = 0; + +header icmp_t { + bit<8> type; + bit<8> code; + bit<16> checksum; +} + +/* Assemble headers in a single struct */ +struct my_headers_t { + ethernet_t ethernet; + arp_t arp; + arp_ipv4_t arp_ipv4; + ipv4_t ipv4; + icmp_t icmp; +} + +/************************************************************************* + *********************** M E T A D A T A ******************************* + *************************************************************************/ + /* Define the global metadata for your program */ + +struct my_metadata_t { + ipv4_addr_t dst_ipv4; + mac_addr_t mac_da; + mac_addr_t mac_sa; + port_id_t egress_port; + mac_addr_t my_mac; +} + +/************************************************************************* + *********************** P A R S E R *********************************** + *************************************************************************/ +parser MyParser( + packet_in packet, + out my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + state start { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + ETHERTYPE_IPV4 : parse_ipv4; + ETHERTYPE_ARP : parse_arp; + default : accept; + } + } + + state parse_arp { + packet.extract(hdr.arp); + transition select(hdr.arp.htype, hdr.arp.ptype, + hdr.arp.hlen, hdr.arp.plen) { + (ARP_HTYPE_ETHERNET, ARP_PTYPE_IPV4, + ARP_HLEN_ETHERNET, ARP_PLEN_IPV4) : parse_arp_ipv4; + default : accept; + } + } + + state parse_arp_ipv4 { + packet.extract(hdr.arp_ipv4); + meta.dst_ipv4 = hdr.arp_ipv4.tpa; + transition accept; + } + + state parse_ipv4 { + packet.extract(hdr.ipv4); + meta.dst_ipv4 = hdr.ipv4.dstAddr; + transition select(hdr.ipv4.protocol) { + IPPROTO_ICMP : parse_icmp; + default : accept; + } + } + + state parse_icmp { + packet.extract(hdr.icmp); + transition accept; + } +} + +/************************************************************************* + ************ C H E C K S U M V E R I F I C A T I O N ************* + *************************************************************************/ +control MyVerifyChecksum( + in my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { } +} + +/************************************************************************* + ************** I N G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyIngress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + action drop() { + mark_to_drop(); + exit; + } + + action set_dst_info(mac_addr_t mac_da, + mac_addr_t mac_sa, + port_id_t egress_port) + { + meta.mac_da = mac_da; + meta.mac_sa = mac_sa; + meta.egress_port = egress_port; + } + + table ipv4_lpm { + key = { meta.dst_ipv4 : lpm; } + actions = { set_dst_info; drop; } + default_action = drop(); + } + + action forward_ipv4() { + hdr.ethernet.dstAddr = meta.mac_da; + hdr.ethernet.srcAddr = meta.mac_sa; + hdr.ipv4.ttl = hdr.ipv4.ttl - 1; + + standard_metadata.egress_spec = meta.egress_port; + } + + action send_arp_reply() { + hdr.ethernet.dstAddr = hdr.arp_ipv4.sha; + hdr.ethernet.srcAddr = meta.mac_da; + + hdr.arp.oper = ARP_OPER_REPLY; + + hdr.arp_ipv4.tha = hdr.arp_ipv4.sha; + hdr.arp_ipv4.tpa = hdr.arp_ipv4.spa; + hdr.arp_ipv4.sha = meta.mac_da; + hdr.arp_ipv4.spa = meta.dst_ipv4; + + standard_metadata.egress_spec = standard_metadata.ingress_port; + } + + action send_icmp_reply() { + mac_addr_t tmp_mac; + ipv4_addr_t tmp_ip; + + tmp_mac = hdr.ethernet.dstAddr; + hdr.ethernet.dstAddr = hdr.ethernet.srcAddr; + hdr.ethernet.srcAddr = tmp_mac; + + tmp_ip = hdr.ipv4.dstAddr; + hdr.ipv4.dstAddr = hdr.ipv4.srcAddr; + hdr.ipv4.srcAddr = tmp_ip; + + hdr.icmp.type = ICMP_ECHO_REPLY; + hdr.icmp.checksum = 0; // For now + + standard_metadata.egress_spec = standard_metadata.ingress_port; + } + + table forward { + key = { + hdr.arp.isValid() : exact; + hdr.arp.oper : ternary; + hdr.arp_ipv4.isValid() : exact; + hdr.ipv4.isValid() : exact; + hdr.icmp.isValid() : exact; + hdr.icmp.type : ternary; + } + actions = { + forward_ipv4; + send_arp_reply; + send_icmp_reply; + drop; + } + const default_action = drop(); + const entries = { + ( true, ARP_OPER_REQUEST, true, false, false, _ ) : + send_arp_reply(); + ( false, _, false, true, false, _ ) : + forward_ipv4(); + ( false, _, false, true, true, ICMP_ECHO_REQUEST ) : + send_icmp_reply(); + } + } + + apply { + meta.my_mac = 0x000102030405; + ipv4_lpm.apply(); + forward.apply(); + } +} + +/************************************************************************* + **************** E G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyEgress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* + ************* C H E C K S U M C O M P U T A T I O N ************** + *************************************************************************/ +control MyComputeChecksum( + inout my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { } +} + +/************************************************************************* + *********************** D E P A R S E R ******************************* + *************************************************************************/ +control MyDeparser( + packet_out packet, + in my_headers_t hdr) +{ + apply { + packet.emit(hdr.ethernet); + /* ARP Case */ + packet.emit(hdr.arp); + packet.emit(hdr.arp_ipv4); + /* IPv4 case */ + packet.emit(hdr.ipv4); + packet.emit(hdr.icmp); + } +} + +V1Switch( + MyParser(), + MyVerifyChecksum(), + MyIngress(), + MyEgress(), + MyComputeChecksum(), + MyDeparser() +) main; diff --git a/P4D2_2017/exercises/calc/README.md b/P4D2_2017/exercises/calc/README.md new file mode 100644 index 0000000..c31e602 --- /dev/null +++ b/P4D2_2017/exercises/calc/README.md @@ -0,0 +1,115 @@ +# Implementing a P4 Calculator + +## Introduction + +The objective of this tutorial is to implement a basic calculator +using a custom protocol header written in P4. The header will contain +an operation to perform and two operands. When a switch receives a +calculator packet header, it will execute the operation on the +operands, and return the result to the sender. + +## Step 1: Run the (incomplete) starter code + +The directory with this README also contains a skeleton P4 program, +`calc.p4`, which initially drops all packets. Your job will be to +extend it to properly implement the calculator logic. + + +As a first step, compile the incomplete `calc.p4` and bring up a +switch in Mininet to test its behavior. + +1. In your shell, run: + ```bash + ./run.sh + ``` + This will: + * compile `calc.p4`, and + * start a Mininet instance with one switches (`s1`) connected to two hosts (`h1`, `h2`). + * The hosts are assigned IPs of `10.0.1.10` and `10.0.2.10`. + + +2. We've written a small Python-based driver program that will allow you +to test your calculator. You can run the driver program directly from the +Mininet command prompt: + +``` +mininet> h1 python calc.py +> +``` + +3. The driver program will provide a new prompt, at which you can type +basic expressions. The test harness will parse your expression, and prepare +a packet with the corresponding operator and operands. It will then send a packet +to the switch for evaluation. When the switch returns the result of the computation, +the test program will print the result. However, because the calculator program +is not implemented, you should see an error message. + +``` +> 1+1 +Didn't receive response +> +``` + + + +## Step 2: Implement Calculator + +To implement the calculator, you will need to define a custom +calculator header, and implement the switch logic to parse header, +perform the requested operation, write the result in the header, and +return the packet to the sender. + +We will use the following header format: + + + 0 1 2 3 + +----------------+----------------+----------------+---------------+ + | P | 4 | Version | Op | + +----------------+----------------+----------------+---------------+ + | Operand A | + +----------------+----------------+----------------+---------------+ + | Operand B | + +----------------+----------------+----------------+---------------+ + | Result | + +----------------+----------------+----------------+---------------+ + + +- P is an ASCII Letter 'P' (0x50) +- 4 is an ASCII Letter '4' (0x34) +- Version is currently 0.1 (0x01) +- Op is an operation to Perform: + - '+' (0x2b) Result = OperandA + OperandB + - '-' (0x2d) Result = OperandA - OperandB + - '&' (0x26) Result = OperandA & OperandB + - '|' (0x7c) Result = OperandA | OperandB + - '^' (0x5e) Result = OperandA ^ OperandB + + +We will assume that the calculator header is carried over Ethernet, and +we will use the Ethernet type 0x1234 to indicate the presence of the header. + + +Given what you have learned so far, your task is to implement the +P4 calculator program. There is no control plane logic, so you need +only worry about the data plane implementation. + + +A working calculator implementation will parse the custom headers, +execute the mathematical operation, write the result in the result field, +and return the packet to the sender. + + +## Step 3: Run your solution + +Follow the instructions from Step 1. This time, you should see the +correct result: + +``` +> 1+1 +2 +> +``` + +If all of this works well. Congratulations! You have finished this +tutorial. + diff --git a/P4D2_2017/exercises/calc/calc.p4 b/P4D2_2017/exercises/calc/calc.p4 new file mode 100644 index 0000000..e01e47d --- /dev/null +++ b/P4D2_2017/exercises/calc/calc.p4 @@ -0,0 +1,127 @@ +/* -*- P4_16 -*- */ + +/* + * P4 Calculator + * + * This program implements a simple protocol. It can be carried over Ethernet + * (Ethertype 0x1234). + * + * The Protocol header looks like this: + * + * 0 1 2 3 + * +----------------+----------------+----------------+---------------+ + * | P | 4 | Version | Op | + * +----------------+----------------+----------------+---------------+ + * | Operand A | + * +----------------+----------------+----------------+---------------+ + * | Operand B | + * +----------------+----------------+----------------+---------------+ + * | Result | + * +----------------+----------------+----------------+---------------+ + * + * P is an ASCII Letter 'P' (0x50) + * 4 is an ASCII Letter '4' (0x34) + * Version is currently 0.1 (0x01) + * Op is an operation to Perform: + * '+' (0x2b) Result = OperandA + OperandB + * '-' (0x2d) Result = OperandA - OperandB + * '&' (0x26) Result = OperandA & OperandB + * '|' (0x7c) Result = OperandA | OperandB + * '^' (0x5e) Result = OperandA ^ OperandB + * + * The device receives a packet, performs the requested operation, fills in the + * result and sends the packet back out of the same port it came in on, while + * swapping the source and destination addresses. + * + * If an unknown operation is specified or the header is not valid, the packet + * is dropped + */ + +#include +#include + +/* + * Define the headers the program will recognize + */ + + +struct my_headers_t { + /* TODO: fill this in */ +} + +struct my_metadata_t { + /* In our case it is empty */ +} + +/************************************************************************* + *********************** P A R S E R *********************************** + *************************************************************************/ +parser MyParser( + packet_in packet, + out my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + state start { transition accept; } +} + +/************************************************************************* + ************ C H E C K S U M V E R I F I C A T I O N ************* + *************************************************************************/ +control MyVerifyChecksum( + in my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { + } +} + +/************************************************************************* + ************** I N G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyIngress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + apply { } +} + +/************************************************************************* + **************** E G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyEgress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* + ************* C H E C K S U M C O M P U T A T I O N ************** + *************************************************************************/ +control MyComputeChecksum( + inout my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { } +} + +/************************************************************************* + *********************** D E P A R S E R ******************************* + *************************************************************************/ +control MyDeparser( + packet_out packet, + in my_headers_t hdr) +{ + apply { } +} + +V1Switch( + MyParser(), + MyVerifyChecksum(), + MyIngress(), + MyEgress(), + MyComputeChecksum(), + MyDeparser() +) main; diff --git a/P4D2_2017/exercises/calc/calc.py b/P4D2_2017/exercises/calc/calc.py new file mode 100755 index 0000000..9136831 --- /dev/null +++ b/P4D2_2017/exercises/calc/calc.py @@ -0,0 +1,95 @@ +#!/usr/bin/env python + +import argparse +import sys +import socket +import random +import struct +import re + +from scapy.all import sendp, send, srp1 +from scapy.all import Packet, hexdump +from scapy.all import Ether, StrFixedLenField, XByteField, IntField +from scapy.all import bind_layers + +class P4calc(Packet): + name = "P4calc" + fields_desc = [ StrFixedLenField("P", "P", length=1), + StrFixedLenField("Four", "4", length=1), + XByteField("version", 0x01), + StrFixedLenField("op", "+", length=1), + IntField("operand_a", 0), + IntField("operand_b", 0), + IntField("result", 0xDEADBABE)] + +bind_layers(Ether, P4calc, type=0x1234) + +class NumParseError(Exception): + pass + +class OpParseError(Exception): + pass + +class Token: + def __init__(self,type,value = None): + self.type = type + self.value = value + +def num_parser(s, i, ts): + pattern = "^\s*([0-9]+)\s*" + match = re.match(pattern,s[i:]) + if match: + ts.append(Token('num', match.group(1))) + return i + match.end(), ts + raise NumParseError('Expected number literal.') + + +def op_parser(s, i, ts): + pattern = "^\s*([-+&|^])\s*" + match = re.match(pattern,s[i:]) + if match: + ts.append(Token('num', match.group(1))) + return i + match.end(), ts + raise NumParseError("Expected binary operator '-', '+', '&', '|', or '^'.") + + +def make_seq(p1, p2): + def parse(s, i, ts): + i,ts2 = p1(s,i,ts) + return p2(s,i,ts2) + return parse + + +def main(): + + p = make_seq(num_parser, make_seq(op_parser,num_parser)) + s = '' + iface = 'h1-eth0' + + while True: + s = str(raw_input('> ')) + if s == "quit": + break + print s + try: + i,ts = p(s,0,[]) + pkt = Ether(dst='00:04:00:00:00:00', type=0x1234) / P4calc(op=ts[1].value, + operand_a=int(ts[0].value), + operand_b=int(ts[2].value)) + + #pkt.show() + resp = srp1(pkt, iface=iface, timeout=1, verbose=False) + if resp: + p4calc=resp[P4calc] + if p4calc: + print p4calc.result + else: + print "cannot find P4calc header in the packet" + else: + print "Didn't receive response" + except Exception as error: + print error + + +if __name__ == '__main__': + main() diff --git a/P4D2_2017/exercises/calc/p4app.json b/P4D2_2017/exercises/calc/p4app.json new file mode 100644 index 0000000..c81fdac --- /dev/null +++ b/P4D2_2017/exercises/calc/p4app.json @@ -0,0 +1,10 @@ +{ + "program": "calc.p4", + "language": "p4-16", + "targets": { + "mininet": { + "num-hosts": 2, + "switch-config": "simple_router.config" + } + } +} diff --git a/P4D2_2017/exercises/calc/run.sh b/P4D2_2017/exercises/calc/run.sh new file mode 100755 index 0000000..d5c1947 --- /dev/null +++ b/P4D2_2017/exercises/calc/run.sh @@ -0,0 +1,5 @@ +P4APPRUNNER=../../utils/p4apprunner.py +mkdir -p build +tar -czf build/p4app.tgz * --exclude='build' +#cd build +sudo python $P4APPRUNNER p4app.tgz --build-dir ./build diff --git a/P4D2_2017/exercises/calc/simple_router.config b/P4D2_2017/exercises/calc/simple_router.config new file mode 100644 index 0000000..e69de29 diff --git a/P4D2_2017/exercises/calc/solution/calc.p4 b/P4D2_2017/exercises/calc/solution/calc.p4 new file mode 100644 index 0000000..a1984be --- /dev/null +++ b/P4D2_2017/exercises/calc/solution/calc.p4 @@ -0,0 +1,263 @@ +/* -*- P4_16 -*- */ + +/* + * P4 Calculator + * + * This program implements a simple protocol. It can be carried over Ethernet + * (Ethertype 0x1234). + * + * The Protocol header looks like this: + * + * 0 1 2 3 + * +----------------+----------------+----------------+---------------+ + * | P | 4 | Version | Op | + * +----------------+----------------+----------------+---------------+ + * | Operand A | + * +----------------+----------------+----------------+---------------+ + * | Operand B | + * +----------------+----------------+----------------+---------------+ + * | Result | + * +----------------+----------------+----------------+---------------+ + * + * P is an ASCII Letter 'P' (0x50) + * 4 is an ASCII Letter '4' (0x34) + * Version is currently 0.1 (0x01) + * Op is an operation to Perform: + * '+' (0x2b) Result = OperandA + OperandB + * '-' (0x2d) Result = OperandA - OperandB + * '&' (0x26) Result = OperandA & OperandB + * '|' (0x7c) Result = OperandA | OperandB + * '^' (0x5e) Result = OperandA ^ OperandB + * + * The device receives a packet, performs the requested operation, fills in the + * result and sends the packet back out of the same port it came in on, while + * swapping the source and destination addresses. + * + * If an unknown operation is specified or the header is not valid, the packet + * is dropped + */ + +#include +#include + +/* + * Define the headers the program will recognize + */ + +/* + * Standard ethernet header + */ +header ethernet_t { + bit<48> dstAddr; + bit<48> srcAddr; + bit<16> etherType; +} + +/* + * This is a custom protocol header for the calculator. We'll use + * ethertype 0x1234 for is (see parser) + */ +const bit<16> P4CALC_ETYPE = 0x1234; +const bit<8> P4CALC_P = 0x50; // 'P' +const bit<8> P4CALC_4 = 0x34; // '4' +const bit<8> P4CALC_VER = 0x01; // v0.1 +const bit<8> P4CALC_PLUS = 0x2b; // '+' +const bit<8> P4CALC_MINUS = 0x2d; // '-' +const bit<8> P4CALC_AND = 0x26; // '&' +const bit<8> P4CALC_OR = 0x7e; // '|' +const bit<8> P4CALC_CARET = 0x5e; // '^' + +header p4calc_t { + bit<8> p; + bit<8> four; + bit<8> ver; + bit<8> op; + bit<32> operand_a; + bit<32> operand_b; + bit<32> res; +} + +/* + * All headers, used in the program needs to be assembed into a single struct. + * We only need to declare the type, but there is no need to instantiate it, + * because it is done "by the architecture", i.e. outside of P4 functions + */ +struct my_headers_t { + ethernet_t ethernet; + p4calc_t p4calc; +} + +/* + * All metadata, globally used in the program, also needs to be assembed + * into a single struct. As in the case of the headers, we only need to + * declare the type, but there is no need to instantiate it, + * because it is done "by the architecture", i.e. outside of P4 functions + */ + +struct my_metadata_t { + /* In our case it is empty */ +} + +/************************************************************************* + *********************** P A R S E R *********************************** + *************************************************************************/ +parser MyParser( + packet_in packet, + out my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + state start { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + P4CALC_ETYPE : check_p4calc; + default : accept; + } + } + + state check_p4calc { + transition select(packet.lookahead().p, + packet.lookahead().four, + packet.lookahead().ver) { + (P4CALC_P, P4CALC_4, P4CALC_VER) : parse_p4calc; + default : accept; + } + } + + state parse_p4calc { + packet.extract(hdr.p4calc); + transition accept; + } +} + +/************************************************************************* + ************ C H E C K S U M V E R I F I C A T I O N ************* + *************************************************************************/ +control MyVerifyChecksum( + in my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { + } +} + +/************************************************************************* + ************** I N G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyIngress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) +{ + action send_back(bit<32> result) { + bit<48> tmp; + + /* Put the result back in */ + hdr.p4calc.res = result; + + /* Swap the MAC addresses */ + tmp = hdr.ethernet.dstAddr; + hdr.ethernet.dstAddr = hdr.ethernet.srcAddr; + hdr.ethernet.srcAddr = tmp; + + /* Send the packet back to the port it came from */ + standard_metadata.egress_spec = standard_metadata.ingress_port; + } + + action operation_add() { + send_back(hdr.p4calc.operand_a + hdr.p4calc.operand_b); + } + + action operation_sub() { + send_back(hdr.p4calc.operand_a - hdr.p4calc.operand_b); + } + + action operation_and() { + send_back(hdr.p4calc.operand_a & hdr.p4calc.operand_b); + } + + action operation_or() { + send_back(hdr.p4calc.operand_a | hdr.p4calc.operand_b); + } + + action operation_xor() { + send_back(hdr.p4calc.operand_a ^ hdr.p4calc.operand_b); + } + + action operation_drop() { + mark_to_drop(); + } + + table calculate { + key = { + hdr.p4calc.op : exact; + } + actions = { + operation_add; + operation_sub; + operation_and; + operation_or; + operation_xor; + operation_drop; + } + const default_action = operation_drop(); + const entries = { + P4CALC_PLUS : operation_add(); + P4CALC_MINUS: operation_sub(); + P4CALC_AND : operation_and(); + P4CALC_OR : operation_or(); + P4CALC_CARET: operation_xor(); + } + } + + + apply { + if (hdr.p4calc.isValid()) { + calculate.apply(); + } else { + operation_drop(); + } + } +} + +/************************************************************************* + **************** E G R E S S P R O C E S S I N G ******************* + *************************************************************************/ +control MyEgress( + inout my_headers_t hdr, + inout my_metadata_t meta, + inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* + ************* C H E C K S U M C O M P U T A T I O N ************** + *************************************************************************/ +control MyComputeChecksum( + inout my_headers_t hdr, + inout my_metadata_t meta) +{ + apply { } +} + +/************************************************************************* + *********************** D E P A R S E R ******************************* + *************************************************************************/ +control MyDeparser( + packet_out packet, + in my_headers_t hdr) +{ + apply { + packet.emit(hdr.ethernet); + packet.emit(hdr.p4calc); + } +} + +V1Switch( + MyParser(), + MyVerifyChecksum(), + MyIngress(), + MyEgress(), + MyComputeChecksum(), + MyDeparser() +) main; diff --git a/P4D2_2017/exercises/ipv4_forward/README.md b/P4D2_2017/exercises/ipv4_forward/README.md new file mode 100644 index 0000000..fa59d2e --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/README.md @@ -0,0 +1,156 @@ +# Implementing L3 Forwarding + +## Introduction + +The objective of this tutorial is to implement basic L3 forwarding. To +keep the exercise small, we will just implement forwarding for IPv4. + +With IPv4 forwarding, the switch must perform the following actions +for every packet: (i) update the source and destination MAC addresses, +(ii) decrement the time-to-live (TTL) in the IP header, and (iii) +forward the packet out the appropriate port. + +Your switch will have a single table, which the control plane will +populate with static rules. Each rule will map an IP address to the +MAC address and output port for the next hop. We have already defined +the control plane rules, so you only need to implement the data plane +logic of your P4 program. + +> **Spoiler alert:** There is a reference solution in the `solution` +> sub-directory. Feel free to compare your implementation to the reference. + + +## Step 1: Run the (incomplete) starter code + +The directory with this README also contains a skeleton P4 program, +`ipv4_forward.p4`, which initially drops all packets. Your job (in the next +step) will be to extend it to properly forward IPv4 packets. + +Before that, let's compile the incomplete `ip4v_forward.p4` and bring up a +switch in Mininet to test its behavior. + +1. In your shell, run: + ```bash + ./run.sh + ``` + This will: + * compile `ip4v_forward.p4`, and + * start a Mininet instance with three switches (`s1`, `s2`, `s3`) configured + in a triangle, each connected to one host (`h1`, `h2`, `h3`). + * The hosts are assigned IPs of `10.0.1.10`, `10.0.2.10`, etc. + +2. You should now see a Mininet command prompt. Open two terminals for `h1` and `h2`, respectively: + ```bash + mininet> xterm h1 h2 + ``` +3. Each host includes a small Python-based messaging client and server. In `h2`'s xterm, start the server: + ```bash + ./receive.py + ``` +4. In `h1`'s xterm, send a message from the client: + ```bash + ./send.py 10.0.2.10 "P4 is cool" + ``` + The message will not be received. +5. Type `exit` to leave each xterm and the Mininet command line. + +The message was not received because each switch is programmed with +`ip4v_forward.p4`, which drops all packets on arrival. Your job is to extend +this file. + +### A note about the control plane + +P4 programs define a packet-processing pipeline, but the rules governing packet +processing are inserted into the pipeline by the control plane. When a rule +matches a packet, its action is invoked with parameters supplied by the control +plane as part of the rule. + +In this exercise, the control plane logic has already been implemented. As +part of bringing up the Mininet instance, the `run.sh` script will install +packet-processing rules in the tables of each switch. These are defined in the +`sX-commands.txt` files, where `X` corresponds to the switch number. + +**Important:** A P4 program also defines the interface between the switch +pipeline and control plane. The `sX-commands.txt` files contain lists of +commands for the BMv2 switch API. These commands refer to specific tables, +keys, and actions by name, and any changes in the P4 program that add or rename +tables, keys, or actions will need to be reflected in these command files. + +## Step 2: Implement L3 forwarding + +The `ipv4_forward.p4` file contains a skeleton P4 program with key pieces of +logic replaced by `TODO` comments. These should guide your +implementation---replace each `TODO` with logic implementing the missing piece. + +A complete `ipv4_forward.p4` will contain the following components: + +1. Header type definitions for Ethernet (`ethernet_t`) and IPv4 (`ipv4_t`). +2. **TODO:** Parsers for Ethernet and IPv4 that populate `ethernet_t` and `ipv4_t` fields. +3. An action to drop a packet, using `mark_to_drop()`. +4. **TODO:** An action (called `ipv4_forward`), which will: + 1. Set the egress port for the next hop. + 2. Update the ethernet destination address with the address of the next hop. + 3. Update the ethernet source address with the address of the switch. + 4. Decrement the TTL. +5. **TODO:** A control that: + 1. Defines a table that will read an IPv4 destination address, and + invoke either `drop` or `ipv4_forward`. + 1. An `apply` block that applies the table. +7. A deparser that selects the order in which fields inserted into the outgoing + packet. +8. A `package` instantiation supplied with the parser, control, and deparser. + > In general, a package also requires instances of checksum verification + > and recomputation controls. These are not necessary for this tutorial + > and are replaced with instantiations of empty controls. + +## Step 3: Run your solution + +Follow the instructions from Step 1. This time, your message from `h1` should +be delivered to `h2`. + +### Food for thought + +The "test suite" for your solution---sending a message from `h1` to `h2`---is +not very robust. What else should you test to be confident of your +implementation? + +> Although the Python `scapy` library is outside the scope of this tutorial, +> it can be used to generate packets for testing. The `send.py` file shows how +> to use it. + +Other questions to consider: + + - How would you enhance your program to support next hops? + - Is this program enough to replace a router? What's missing? + +### Troubleshooting + +There are several ways that problems might manifest: + +1. `ipv4_forward.p4` fails to compile. In this case, `run.sh` will report the +error emitted from the compiler and stop. + +2. `ipv4_forward.p4` compiles but does not support the control plane rules in +the `sX-commands.txt` files that `run.sh` tries to install using the BMv2 CLI. +In this case, `run.sh` will report these errors to `stderr`. Use these error +messages to fix your `ipv4_forward.p4` implementation. + +3. `ipv4_forward.p4` compiles, and the control plane rules are installed, but +the switch does not process packets in the desired way. The +`build/logs/.log` files contain trace messages describing how each +switch processes each packet. The output is detailed and can help pinpoint +logic errors in your implementation. + +#### Cleaning up Mininet + +In the latter two cases above, `run.sh` may leave a Mininet instance running in +the background. Use the following command to clean up these instances: + +```bash +mn -c +``` + +## Next Steps + +Congratulations, your implementation works! Move on to the next exercise: +implementing basic network telemetry [Multi-Hop Route Inspection](../mri). diff --git a/P4D2_2017/exercises/ipv4_forward/ipv4_forward.p4 b/P4D2_2017/exercises/ipv4_forward/ipv4_forward.p4 new file mode 100644 index 0000000..414612c --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/ipv4_forward.p4 @@ -0,0 +1,170 @@ +/* -*- P4_16 -*- */ +#include +#include + +const bit<16> TYPE_IPV4 = 0x800; + +/************************************************************************* +*********************** H E A D E R S *********************************** +*************************************************************************/ + +typedef bit<9> egressSpec_t; +typedef bit<48> macAddr_t; +typedef bit<32> ip4Addr_t; + +header ethernet_t { + macAddr_t dstAddr; + macAddr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ip4Addr_t srcAddr; + ip4Addr_t dstAddr; +} + +struct metadata { + /* empty */ +} + +struct headers { + ethernet_t ethernet; + ipv4_t ipv4; +} + +/************************************************************************* +*********************** P A R S E R *********************************** +*************************************************************************/ + +parser ParserImpl(packet_in packet, + out headers hdr, + inout metadata meta, + inout standard_metadata_t standard_metadata) { + + + state start { + /* TODO: add transition to parsing ethernet */ + transition accept; + } + + state parse_ethernet { + /* TODO: add parsing ethernet */ + } + + state parse_ipv4 { + /* TODO: add parsing ipv4 */ + } + +} + + +/************************************************************************* +************ C H E C K S U M V E R I F I C A T I O N ************* +*************************************************************************/ + +control verifyChecksum(in headers hdr, inout metadata meta) { + apply { } +} + + +/************************************************************************* +************** I N G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + + /* This action will drop packets */ + action drop() { + mark_to_drop(); + } + + action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) { + /* + * TODO: Implement the logic to: + * 1. Set the standard_metadata.egress_spec to the output port. + * 2. Set the ethernet srcAddr to the ethernet dstAddr. + * 3. Set the ethernet dstAddr to the dstAddr passed as a parameter. + * 4. Decrement the IP TTL. + * BONUS: Handle the case where TTL is 0. + */ + } + + table ipv4_lpm { + key = { + /* TODO: declare that the table will do a longest-prefix match (lpm) + on the IP destination address. */ + } + actions = { + /* TODO: declare the possible actions: ipv4_forward or drop. */ + NoAction; + } + size = 1024; + default_action = NoAction(); + } + + apply { + /* TODO: replace drop with logic to: + * 1. Check if the ipv4 header is valid. + * 2. apply the table ipv4_lpm. + */ + drop(); + } +} + +/************************************************************************* +**************** E G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control egress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* +************* C H E C K S U M C O M P U T A T I O N ************** +*************************************************************************/ + +control computeChecksum( + inout headers hdr, + inout metadata meta) +{ + /* + * Ignore checksum for now. The reference solution contains a checksum + * implementation. + */ + apply { } +} + + +/************************************************************************* +*********************** D E P A R S E R ******************************* +*************************************************************************/ + +control DeparserImpl(packet_out packet, in headers hdr) { + apply { + packet.emit(hdr.ethernet); + packet.emit(hdr.ipv4); + } +} + +/************************************************************************* +*********************** S W I T C H ******************************* +*************************************************************************/ + +V1Switch( +ParserImpl(), +verifyChecksum(), +ingress(), +egress(), +computeChecksum(), +DeparserImpl() +) main; diff --git a/P4D2_2017/exercises/ipv4_forward/p4app.json b/P4D2_2017/exercises/ipv4_forward/p4app.json new file mode 100644 index 0000000..05e314d --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/p4app.json @@ -0,0 +1,33 @@ +{ + "program": "ipv4_forward.p4", + "language": "p4-16", + "targets": { + "multiswitch": { + "auto-control-plane": true, + "cli": true, + "pcap_dump": true, + "bmv2_log": true, + "links": [["h1", "s1"], ["s1", "s2"], ["s1", "s3"], ["s3", "s2"], ["s2", "h2"], ["s3", "h3"]], + "hosts": { + "h1": { + }, + "h2": { + }, + "h3": { + } + + }, + "switches": { + "s1": { + "entries": "s1-commands.txt" + }, + "s2": { + "entries": "s2-commands.txt" + }, + "s3": { + "entries": "s3-commands.txt" + } + } + } + } +} diff --git a/P4D2_2017/exercises/ipv4_forward/receive.py b/P4D2_2017/exercises/ipv4_forward/receive.py new file mode 100755 index 0000000..6056a02 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/receive.py @@ -0,0 +1,50 @@ +#!/usr/bin/env python +import sys +import struct + +from scapy.all import sniff, sendp, hexdump, get_if_list, get_if_hwaddr +from scapy.all import Packet, IPOption +from scapy.all import ShortField, IntField, LongField, BitField, FieldListField, FieldLenField +from scapy.all import IP, UDP, Raw +from scapy.layers.inet import _IPOption_HDR + +def get_if(): + ifs=get_if_list() + iface=None + for i in get_if_list(): + if "eth0" in i: + iface=i + break; + if not iface: + print "Cannot find eth0 interface" + exit(1) + return iface + +class IPOption_MRI(IPOption): + name = "MRI" + option = 31 + fields_desc = [ _IPOption_HDR, + FieldLenField("length", None, fmt="B", + length_of="swids", + adjust=lambda pkt,l:l+4), + ShortField("count", 0), + FieldListField("swids", + [], + IntField("", 0), + length_from=lambda pkt:pkt.count*4) ] +def handle_pkt(pkt): + print "got a packet" + pkt.show2() +# hexdump(pkt) + sys.stdout.flush() + + +def main(): + iface = 'h2-eth0' + print "sniffing on %s" % iface + sys.stdout.flush() + sniff(filter="udp and port 4321", iface = iface, + prn = lambda x: handle_pkt(x)) + +if __name__ == '__main__': + main() diff --git a/P4D2_2017/exercises/ipv4_forward/run.sh b/P4D2_2017/exercises/ipv4_forward/run.sh new file mode 100755 index 0000000..d5c1947 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/run.sh @@ -0,0 +1,5 @@ +P4APPRUNNER=../../utils/p4apprunner.py +mkdir -p build +tar -czf build/p4app.tgz * --exclude='build' +#cd build +sudo python $P4APPRUNNER p4app.tgz --build-dir ./build diff --git a/P4D2_2017/exercises/ipv4_forward/s1-commands.txt b/P4D2_2017/exercises/ipv4_forward/s1-commands.txt new file mode 100644 index 0000000..2045b53 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/s1-commands.txt @@ -0,0 +1,4 @@ +table_set_default ipv4_lpm drop +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => 00:aa:00:01:00:01 1 +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => f2:ed:e6:df:4e:fa 2 +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => f2:ed:e6:df:4e:fb 3 diff --git a/P4D2_2017/exercises/ipv4_forward/s2-commands.txt b/P4D2_2017/exercises/ipv4_forward/s2-commands.txt new file mode 100644 index 0000000..48f1ed1 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/s2-commands.txt @@ -0,0 +1,4 @@ +table_set_default ipv4_lpm drop +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => 00:aa:00:02:00:02 1 +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => 22:a8:04:41:ab:d3 2 +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => 22:a8:04:41:ab:d4 3 diff --git a/P4D2_2017/exercises/ipv4_forward/s3-commands.txt b/P4D2_2017/exercises/ipv4_forward/s3-commands.txt new file mode 100644 index 0000000..7a182b6 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/s3-commands.txt @@ -0,0 +1,4 @@ +table_set_default ipv4_lpm drop +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => 00:aa:00:03:00:01 1 +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => f2:ed:e6:df:4e:fb 2 +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => f2:ed:e6:df:4e:fa 3 diff --git a/P4D2_2017/exercises/ipv4_forward/send.py b/P4D2_2017/exercises/ipv4_forward/send.py new file mode 100755 index 0000000..ba73211 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/send.py @@ -0,0 +1,40 @@ +#!/usr/bin/env python +import argparse +import sys +import socket +import random +import struct + +from scapy.all import sendp, send, get_if_list, get_if_hwaddr +from scapy.all import Packet +from scapy.all import Ether, IP, UDP + +def get_if(): + ifs=get_if_list() + iface=None # "h1-eth0" + for i in get_if_list(): + if "eth0" in i: + iface=i + break; + if not iface: + print "Cannot find eth0 interface" + exit(1) + return iface + +def main(): + + if len(sys.argv)<3: + print 'pass 2 arguments: ""' + exit(1) + + addr = socket.gethostbyname(sys.argv[1]) + iface = get_if() + + print "sending on interface %s to %s" % (iface, str(addr)) + pkt = Ether(src=get_if_hwaddr(iface), dst='ff:ff:ff:ff:ff:ff') / IP(dst=addr) / UDP(dport=4321, sport=1234) / sys.argv[2] + pkt.show2() + sendp(pkt, iface=iface, verbose=False) + + +if __name__ == '__main__': + main() diff --git a/P4D2_2017/exercises/ipv4_forward/solution/ipv4_forward.p4 b/P4D2_2017/exercises/ipv4_forward/solution/ipv4_forward.p4 new file mode 100644 index 0000000..1130b81 --- /dev/null +++ b/P4D2_2017/exercises/ipv4_forward/solution/ipv4_forward.p4 @@ -0,0 +1,180 @@ +/* -*- P4_16 -*- */ +#include +#include + +const bit<16> TYPE_IPV4 = 0x800; + +/************************************************************************* +*********************** H E A D E R S *********************************** +*************************************************************************/ + +typedef bit<9> egressSpec_t; +typedef bit<48> macAddr_t; +typedef bit<32> ip4Addr_t; + +header ethernet_t { + macAddr_t dstAddr; + macAddr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ip4Addr_t srcAddr; + ip4Addr_t dstAddr; +} + +struct metadata { + /* empty */ +} + +struct headers { + ethernet_t ethernet; + ipv4_t ipv4; +} + +/************************************************************************* +*********************** P A R S E R *********************************** +*************************************************************************/ + +parser ParserImpl(packet_in packet, + out headers hdr, + inout metadata meta, + inout standard_metadata_t standard_metadata) { + + state start { + transition parse_ethernet; + } + + state parse_ethernet { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + TYPE_IPV4: parse_ipv4; + default: accept; + } + } + + state parse_ipv4 { + packet.extract(hdr.ipv4); + transition accept; + } + +} + + +/************************************************************************* +************ C H E C K S U M V E R I F I C A T I O N ************* +*************************************************************************/ + +control verifyChecksum(in headers hdr, inout metadata meta) { + apply { } +} + + +/************************************************************************* +************** I N G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + action drop() { + mark_to_drop(); + } + + action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) { + standard_metadata.egress_spec = port; + hdr.ethernet.srcAddr = hdr.ethernet.dstAddr; + hdr.ethernet.dstAddr = dstAddr; + hdr.ipv4.ttl = hdr.ipv4.ttl - 1; + } + + table ipv4_lpm { + key = { + hdr.ipv4.dstAddr: lpm; + } + actions = { + ipv4_forward; + drop; + NoAction; + } + size = 1024; + default_action = NoAction(); + } + + apply { + if (hdr.ipv4.isValid()) { + ipv4_lpm.apply(); + } + } +} + +/************************************************************************* +**************** E G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control egress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* +************* C H E C K S U M C O M P U T A T I O N ************** +*************************************************************************/ + +control computeChecksum( + inout headers hdr, + inout metadata meta) +{ + Checksum16() ipv4_checksum; + + apply { + if (hdr.ipv4.isValid()) { + hdr.ipv4.hdrChecksum = ipv4_checksum.get( + { + hdr.ipv4.version, + hdr.ipv4.ihl, + hdr.ipv4.diffserv, + hdr.ipv4.totalLen, + hdr.ipv4.identification, + hdr.ipv4.flags, + hdr.ipv4.fragOffset, + hdr.ipv4.ttl, + hdr.ipv4.protocol, + hdr.ipv4.srcAddr, + hdr.ipv4.dstAddr + }); + } + } +} + + +/************************************************************************* +*********************** D E P A R S E R ******************************* +*************************************************************************/ + +control DeparserImpl(packet_out packet, in headers hdr) { + apply { + packet.emit(hdr.ethernet); + packet.emit(hdr.ipv4); + } +} + +/************************************************************************* +*********************** S W I T C H ******************************* +*************************************************************************/ + +V1Switch( +ParserImpl(), +verifyChecksum(), +ingress(), +egress(), +computeChecksum(), +DeparserImpl() +) main; diff --git a/P4D2_2017/exercises/mri/README.md b/P4D2_2017/exercises/mri/README.md new file mode 100644 index 0000000..2971bbc --- /dev/null +++ b/P4D2_2017/exercises/mri/README.md @@ -0,0 +1,206 @@ +# Implementing MRI + +## Introduction + +The objective of this tutorial is to extend basic L3 forwarding with a +scaled-down version of In-Band Network Telemetry (INT), which we call +Multi-Hop Route Inspection (MRI). + +MRI allows users to track the path that every packet travels through +the network. To support this functionality, you will need to write a +P4 program that appends an ID to the header stack of every packet. At +the destination, the sequence of switch IDs correspond to the path. + +As before, we have already defined the control plane rules, so you +only need to implement the data plane logic of your P4 program. + +> **Spoiler alert:** There is a reference solution in the `solution` +> sub-directory. Feel free to compare your implementation to the reference. + +## Step 1: Run the (incomplete) starter code + +The directory with this README also contains a skeleton P4 program, +`mri.p4`, which initially implements L3 forwarding. Your job (in the +next step) will be to extend it to properly append the MRI custom +headers. + +Before that, let's compile the incomplete `mri.p4` and bring up a +switch in Mininet to test its behavior. + +1. In your shell, run: + ```bash + ./run.sh + ``` + This will: + * compile `mri.p4`, and + * start a Mininet instance with three switches (`s1`, `s2`, `s3`) configured + in a triangle, each connected to one host (`h1`, `h2`, `h3`). + * The hosts are assigned IPs of `10.0.1.10`, `10.0.2.10`, etc. + +2. You should now see a Mininet command prompt. Open two terminals for `h1` and `h2`, respectively: + ```bash + mininet> xterm h1 h2 + ``` +3. Each host includes a small Python-based messaging client and server. In `h2`'s xterm, start the server: + ```bash + ./receive.py + ``` +4. In `h1`'s xterm, send a message from the client: + ```bash + ./send.py 10.0.2.10 "P4 is cool" + ``` + The message "P4 is cool" should be received in `h2`'s xterm, +5. Type `exit` to leave each xterm and the Mininet command line. + +You should see the message received at host `h2`, but without any information +about the path the message took. Your job is to extend the code in `mri.p4` to +implement the MRI logic to record the path. + + +### A note about the control plane + +P4 programs define a packet-processing pipeline, but the rules governing packet +processing are inserted into the pipeline by the control plane. When a rule +matches a packet, its action is invoked with parameters supplied by the control +plane as part of the rule. + +In this exercise, the control plane logic has already been implemented. As +part of bringing up the Mininet instance, the `run.sh` script will install +packet-processing rules in the tables of each switch. These are defined in the +`sX-commands.txt` files, where `X` corresponds to the switch number. + + +## Step 2: Implement MRI + + +The `mri.p4` file contains a skeleton P4 program with key pieces of +logic replaced by `TODO` comments. These should guide your +implementation---replace each `TODO` with logic implementing the missing piece. + +MRI will require two custom headers. The first header, `mri_t`, +contains a single field `count`, which indicates the number of switch +IDs that follow. The second header, `switch_t`, contains a single +field with the switch ID. + +One of the biggest challenges in implementing MRI is handling the +recursive logic for parsing these two headers. We will use a +`parser_metadata` field, `remaining`, to keep track of how many +`switch_t` headers we need to parse. In the `parse_mri` state, this +field should be set to `hdr.mri.count`. In the `parse_swid` state, +this field should be decremented. The `parse_swid` state will +transition to itself until `remaining` is 0. + +The MRI custom headers will be carried inside an IP Options +header. The IP Options header contains a field, `option`, which +indicates the type of the option. We will use a special type 31 to +indicate the presence of the MRI headers. + +Beyond the parser logic, you will add a table, `swid` to store the +switch ID, and actions that add the `mri_t` header if it doesn't +exist, increment the `count` field, and append a `switch_t` header. + + +A complete `mri.p4` will contain the following components: + + +1. Header type definitions for Ethernet (`ethernet_t`), IPv4 (`ipv4_t`), + IP Options (`ipv4_option_t`), MRI (`mri_t`), and Switch (`switch_t`). +2. Parsers for Ethernet, IPv4, IP Options, MRI, and Switch that will +populate `ethernet_t`, `ipv4_t`, `ipv4_option_t`, `mri_t`, and +`switch_t`. +3. An action to drop a packet, using `mark_to_drop()`. +4. An action (called `ipv4_forward`), which will: + 1. Set the egress port for the next hop. + 2. Update the ethernet destination address with the address of the next hop. + 3. Update the ethernet source address with the address of the switch. + 4. Decrement the TTL. +5. An action (called `add_mri_option`) that will add the IP Options and MRI +header. Note that you can use the `setValid()` function, which adds a +header if it does not exist, but otherwise leaves the packet +unmodified. +6. An action (called `add_swid`) that will add the switch ID header. +7. A table (`swid`) to store the switch ID, and calls `add_swid`. +8. A control that: + 1. Defines a table that will read an IPv4 destination address, and + invoke either `drop` or `ipv4_forward`. + 1. An `apply` block that applies the table. +9. A deparser that selects the order in which fields inserted into the outgoing + packet. +10. A `package` instantiation supplied with the parser, control, and deparser. + + > In general, a package also requires instances of checksum verification + > and recomputation controls. These are not necessary for this tutorial + > and are replaced with instantiations of empty controls. + + +## Step 3: Run your solution + +Follow the instructions from Step 1. This time, when your message from `h1` is + delivered to `h2`, you should see the seqeunce of switches +through which the packet traveled. The expected output will look like the +following, which shows the MRI header, with a `count` of 2, and switch ids (`swids`) 2 and 1. + +``` + +got a packet +###[ Ethernet ]### + dst = 00:aa:00:02:00:02 + src = f2:ed:e6:df:4e:fa + type = 0x800 +###[ IP ]### + version = 4L + ihl = 8L + tos = 0x0 + len = 33 + id = 1 + flags = + frag = 0L + ttl = 62 + proto = udp + chksum = 0x63b8 + src = 10.0.1.10 + dst = 10.0.2.10 + \options \ + |###[ MRI ]### + | copy_flag = 1L + | optclass = debug + | option = 31L + | length = 12 + | count = 2 + | swids = [2, 1] +``` + +### Troubleshooting + +There are several ways that problems might manifest: + +1. `mri.p4` fails to compile. In this case, `run.sh` will report the +error emitted from the compiler and stop. + +1. `mri.p4` compiles but does not support the control plane rules in +the `sX-commands.txt` files that `run.sh` tries to install using the BMv2 CLI. +In this case, `run.sh` will report these errors to `stderr`. Use these error +messages to fix your `ipv4_forward.p4` implementation. + +1. `mri.p4` compiles, and the control plane rules are installed, but +the switch does not process packets in the desired way. The +`build/logs/.log` files contain trace messages describing how each +switch processes each packet. The output is detailed and can help pinpoint +logic errors in your implementation. + +#### Cleaning up Mininet + +In the latter two cases above, `run.sh` may leave a Mininet instance running in +the background. Use the following command to clean up these instances: + +```bash +mn -c +``` + +## Next Steps + +Congratulations, your implementation works! Move on to the next exercise: +implementing an [ARP and ICMP Responder](../arp). + + + diff --git a/P4D2_2017/exercises/mri/mri.p4 b/P4D2_2017/exercises/mri/mri.p4 new file mode 100644 index 0000000..d602260 --- /dev/null +++ b/P4D2_2017/exercises/mri/mri.p4 @@ -0,0 +1,286 @@ +/* -*- P4_16 -*- */ +#include +#include + +const bit<8> UDP_PROTOCOL = 0x11; +const bit<16> TYPE_IPV4 = 0x800; +const bit<5> IPV4_OPTION_MRI = 31; + + +#define MAX_HOPS 9 + +/************************************************************************* +*********************** H E A D E R S *********************************** +*************************************************************************/ + +typedef bit<9> egressSpec_t; +typedef bit<48> macAddr_t; +typedef bit<32> ip4Addr_t; +typedef bit<32> switchID_t; + +header ethernet_t { + macAddr_t dstAddr; + macAddr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ip4Addr_t srcAddr; + ip4Addr_t dstAddr; +} + +header ipv4_option_t { + bit<1> copyFlag; + bit<2> optClass; + bit<5> option; + bit<8> optionLength; +} + +header mri_t { + bit<16> count; +} + +header switch_t { + switchID_t swid; +} + +struct ingress_metadata_t { + bit<16> count; +} + +struct parser_metadata_t { + bit<16> remaining; +} + +struct metadata { + ingress_metadata_t ingress_metadata; + parser_metadata_t parser_metadata; +} + +struct headers { + ethernet_t ethernet; + ipv4_t ipv4; + ipv4_option_t ipv4_option; + mri_t mri; + switch_t[MAX_HOPS] swids; +} + +error { IPHeaderTooShort } + +/************************************************************************* +*********************** P A R S E R *********************************** +*************************************************************************/ + +parser ParserImpl(packet_in packet, +out headers hdr, +inout metadata meta, +inout standard_metadata_t standard_metadata) { + + state start { + transition parse_ethernet; + } + + state parse_ethernet { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + TYPE_IPV4: parse_ipv4; + default: accept; + } + } + + state parse_ipv4 { + packet.extract(hdr.ipv4); + verify(hdr.ipv4.ihl >= 5, error.IPHeaderTooShort); + /* + * TODO: Modify the next line to select on the value of hdr.ipv4.ihl. + * If the value of hdr.ipv4.ihl is set to 5, accept. + * Otherwise, transition to parse_ipv4_option. + */ + transition accept; + } + + /* TODO: Implement the logic for parse_ipv4_options, parse_mri, and parse_swid */ + + + state parse_ipv4_option { + /* + * TODO: Add logic to: + * - Extract the ipv4_option header. + * - If the value is equal to IPV4_OPTION_MRI, transition to parse_mri. + * - Otherwise, accept. + */ + } + + state parse_mri { + /* + * TODO: Add logic to: + * - Extract hdr.mri. + * - Set meta.parser_metadata.remaining to hdr.mri.count + * - Select on the value of meta.parser_metadata.remaining + * - If the value is equal to 0, accept. + * - Otherwise, transition to parse_swid. + */ + } + + state parse_swid { + /* + * TODO: Add logic to: + * - Extract hdr.swids.next. + * - Decrement meta.parser_metadata.remaining by 1 + * - Select on the value of meta.parser_metadata.remaining + * - If the value is equal to 0, accept. + * - Otherwise, transition to parse_swid. + */ + } + +} + + +/************************************************************************* +************ C H E C K S U M V E R I F I C A T I O N ************* +*************************************************************************/ + +control verifyChecksum(in headers hdr, inout metadata meta) { + apply { } +} + + +/************************************************************************* +************** I N G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + action drop() { + mark_to_drop(); + } + + action add_mri_option() { + /* + * TODO: add logic to: + * - Call setValid() on hdr.ipv4_option, which will add the header if it is not + * there, or leave the packet unchanged. + * - Set hdr.ipv4_option.copyFlag to 1 + * - Set hdr.ipv4_option.optClass to 2 + * - Set hdr.ipv4_option.option to IPV4_OPTION_MRI + * - Set the hdr.ipv4_option.optionLength to 4 + * - Call setValid() on hdr.mri + * - Set hdr.mri.count to 0 + * - Increment hdr.ipv4.ihl by 1 + */ + } + + action add_swid(switchID_t id) { + + /* + * TODO: add logic to: + - Increment hdr.mri.count by 1 + - Add a new swid header by calling push_front(1) on hdr.swids. + - Set hdr.swids[0].swid to the id paremeter + - Incremement hdr.ipv4.ihl by 1 + - Incrememtn hdr.ipv4_option.optionLength by 4 + */ + } + + action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) { + standard_metadata.egress_spec = port; + hdr.ethernet.srcAddr = hdr.ethernet.dstAddr; + hdr.ethernet.dstAddr = dstAddr; + hdr.ipv4.ttl = hdr.ipv4.ttl - 1; + } + + table swid { + actions = + { + /* TODO: repace NoAction with the correct action */ + NoAction; + } + /* TODO: set a default action. */ + } + + table ipv4_lpm { + key = { + hdr.ipv4.dstAddr: lpm; + } + actions = { + ipv4_forward; + drop; + NoAction; + } + size = 1024; + default_action = NoAction(); + } + + apply { + + ipv4_lpm.apply(); + + /* + * TODO: add logic to: + * - If hdr.ipv4 is valid: + * - Apply table ipv4_lpm + * - If hdr.mri is not valid, call add_mri_option() + * - Apply table swid + */ + } +} + +/************************************************************************* +**************** E G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control egress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* +************* C H E C K S U M C O M P U T A T I O N ************** +*************************************************************************/ + + +control computeChecksum( + inout headers hdr, + inout metadata meta) +{ + /* + * Ignore checksum for now. The reference solution contains a checksum + * implementation. + */ + apply { } +} + +/************************************************************************* +*********************** D E P A R S E R ******************************* +*************************************************************************/ + +control DeparserImpl(packet_out packet, in headers hdr) { + apply { + packet.emit(hdr.ethernet); + packet.emit(hdr.ipv4); + packet.emit(hdr.ipv4_option); + packet.emit(hdr.mri); + packet.emit(hdr.swids); + } +} + +/************************************************************************* +*********************** S W I T C H ******************************* +*************************************************************************/ + +V1Switch( +ParserImpl(), +verifyChecksum(), +ingress(), +egress(), +computeChecksum(), +DeparserImpl() +) main; diff --git a/P4D2_2017/exercises/mri/p4app.json b/P4D2_2017/exercises/mri/p4app.json new file mode 100644 index 0000000..6ffe32f --- /dev/null +++ b/P4D2_2017/exercises/mri/p4app.json @@ -0,0 +1,33 @@ +{ + "program": "mri.p4", + "language": "p4-16", + "targets": { + "multiswitch": { + "auto-control-plane": true, + "cli": true, + "pcap_dump": true, + "bmv2_log": true, + "links": [["h1", "s1"], ["s1", "s2"], ["s1", "s3"], ["s3", "s2"], ["s2", "h2"], ["s3", "h3"]], + "hosts": { + "h1": { + }, + "h2": { + }, + "h3": { + } + + }, + "switches": { + "s1": { + "entries": "s1-commands.txt" + }, + "s2": { + "entries": "s2-commands.txt" + }, + "s3": { + "entries": "s3-commands.txt" + } + } + } + } +} diff --git a/P4D2_2017/exercises/mri/receive.py b/P4D2_2017/exercises/mri/receive.py new file mode 100755 index 0000000..6056a02 --- /dev/null +++ b/P4D2_2017/exercises/mri/receive.py @@ -0,0 +1,50 @@ +#!/usr/bin/env python +import sys +import struct + +from scapy.all import sniff, sendp, hexdump, get_if_list, get_if_hwaddr +from scapy.all import Packet, IPOption +from scapy.all import ShortField, IntField, LongField, BitField, FieldListField, FieldLenField +from scapy.all import IP, UDP, Raw +from scapy.layers.inet import _IPOption_HDR + +def get_if(): + ifs=get_if_list() + iface=None + for i in get_if_list(): + if "eth0" in i: + iface=i + break; + if not iface: + print "Cannot find eth0 interface" + exit(1) + return iface + +class IPOption_MRI(IPOption): + name = "MRI" + option = 31 + fields_desc = [ _IPOption_HDR, + FieldLenField("length", None, fmt="B", + length_of="swids", + adjust=lambda pkt,l:l+4), + ShortField("count", 0), + FieldListField("swids", + [], + IntField("", 0), + length_from=lambda pkt:pkt.count*4) ] +def handle_pkt(pkt): + print "got a packet" + pkt.show2() +# hexdump(pkt) + sys.stdout.flush() + + +def main(): + iface = 'h2-eth0' + print "sniffing on %s" % iface + sys.stdout.flush() + sniff(filter="udp and port 4321", iface = iface, + prn = lambda x: handle_pkt(x)) + +if __name__ == '__main__': + main() diff --git a/P4D2_2017/exercises/mri/run.sh b/P4D2_2017/exercises/mri/run.sh new file mode 100755 index 0000000..d5c1947 --- /dev/null +++ b/P4D2_2017/exercises/mri/run.sh @@ -0,0 +1,5 @@ +P4APPRUNNER=../../utils/p4apprunner.py +mkdir -p build +tar -czf build/p4app.tgz * --exclude='build' +#cd build +sudo python $P4APPRUNNER p4app.tgz --build-dir ./build diff --git a/P4D2_2017/exercises/mri/s1-commands.txt b/P4D2_2017/exercises/mri/s1-commands.txt new file mode 100644 index 0000000..5242cc1 --- /dev/null +++ b/P4D2_2017/exercises/mri/s1-commands.txt @@ -0,0 +1,5 @@ +table_set_default ipv4_lpm drop +table_set_default swid add_swid 1 +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => 00:aa:00:01:00:01 1 +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => f2:ed:e6:df:4e:fa 2 +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => f2:ed:e6:df:4e:fb 3 diff --git a/P4D2_2017/exercises/mri/s2-commands.txt b/P4D2_2017/exercises/mri/s2-commands.txt new file mode 100644 index 0000000..b8d2bae --- /dev/null +++ b/P4D2_2017/exercises/mri/s2-commands.txt @@ -0,0 +1,5 @@ +table_set_default ipv4_lpm drop +table_set_default swid add_swid 2 +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => 00:aa:00:02:00:02 1 +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => 22:a8:04:41:ab:d3 2 +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => 22:a8:04:41:ab:d4 3 diff --git a/P4D2_2017/exercises/mri/s3-commands.txt b/P4D2_2017/exercises/mri/s3-commands.txt new file mode 100644 index 0000000..3da9428 --- /dev/null +++ b/P4D2_2017/exercises/mri/s3-commands.txt @@ -0,0 +1,5 @@ +table_set_default ipv4_lpm drop +table_set_default swid add_swid 3 +table_add ipv4_lpm ipv4_forward 10.0.3.10/32 => 00:aa:00:03:00:01 1 +table_add ipv4_lpm ipv4_forward 10.0.1.10/32 => f2:ed:e6:df:4e:fb 2 +table_add ipv4_lpm ipv4_forward 10.0.2.10/32 => f2:ed:e6:df:4e:fa 3 diff --git a/P4D2_2017/exercises/mri/send.py b/P4D2_2017/exercises/mri/send.py new file mode 100755 index 0000000..368be7c --- /dev/null +++ b/P4D2_2017/exercises/mri/send.py @@ -0,0 +1,58 @@ +#!/usr/bin/env python + +import argparse +import sys +import socket +import random +import struct + +from scapy.all import sendp, send, hexdump, get_if_list, get_if_hwaddr +from scapy.all import Packet, IPOption +from scapy.all import Ether, IP, UDP +from scapy.all import IntField, FieldListField, FieldLenField, ShortField +from scapy.layers.inet import _IPOption_HDR + +def get_if(): + ifs=get_if_list() + iface=None # "h1-eth0" + for i in get_if_list(): + if "eth0" in i: + iface=i + break; + if not iface: + print "Cannot find eth0 interface" + exit(1) + return iface + +class IPOption_MRI(IPOption): + name = "MRI" + option = 31 + fields_desc = [ _IPOption_HDR, + FieldLenField("length", None, fmt="B", + length_of="swids", + adjust=lambda pkt,l:l+4), + ShortField("count", 0), + FieldListField("swids", + [], + IntField("", 0), + length_from=lambda pkt:pkt.count*4) ] + + +def main(): + + if len(sys.argv)<3: + print 'pass 2 arguments: ""' + exit(1) + + addr = socket.gethostbyname(sys.argv[1]) + iface = get_if() + + pkt = Ether(src=get_if_hwaddr(iface), dst="ff:ff:ff:ff:ff:ff") / IP(dst=addr) / UDP(dport=4321, sport=1234) / sys.argv[2] + #pkt = Ether(src=get_if_hwaddr(iface), dst="ff:ff:ff:ff:ff:ff") / IP(dst=addr, options = IPOption_MRI(count=2, swids=[3,4])) / UDP(dport=4321, sport=1234) / sys.argv[2] + pkt.show2() + #hexdump(pkt) + sendp(pkt, iface=iface) + + +if __name__ == '__main__': + main() diff --git a/P4D2_2017/exercises/mri/solution/mri.p4 b/P4D2_2017/exercises/mri/solution/mri.p4 new file mode 100644 index 0000000..16026af --- /dev/null +++ b/P4D2_2017/exercises/mri/solution/mri.p4 @@ -0,0 +1,278 @@ +/* -*- P4_16 -*- */ +#include +#include + +const bit<8> UDP_PROTOCOL = 0x11; +const bit<16> TYPE_IPV4 = 0x800; +const bit<5> IPV4_OPTION_MRI = 31; + +#define MAX_HOPS 9 + +/************************************************************************* +*********************** H E A D E R S *********************************** +*************************************************************************/ + +typedef bit<9> egressSpec_t; +typedef bit<48> macAddr_t; +typedef bit<32> ip4Addr_t; +typedef bit<32> switchID_t; + +header ethernet_t { + macAddr_t dstAddr; + macAddr_t srcAddr; + bit<16> etherType; +} + +header ipv4_t { + bit<4> version; + bit<4> ihl; + bit<8> diffserv; + bit<16> totalLen; + bit<16> identification; + bit<3> flags; + bit<13> fragOffset; + bit<8> ttl; + bit<8> protocol; + bit<16> hdrChecksum; + ip4Addr_t srcAddr; + ip4Addr_t dstAddr; +} + +header ipv4_option_t { + bit<1> copyFlag; + bit<2> optClass; + bit<5> option; + bit<8> optionLength; +} + +header mri_t { + bit<16> count; +} + +header switch_t { + switchID_t swid; +} + +struct ingress_metadata_t { + bit<16> count; +} + +struct parser_metadata_t { + bit<16> remaining; +} + +struct metadata { + ingress_metadata_t ingress_metadata; + parser_metadata_t parser_metadata; +} + +struct headers { + ethernet_t ethernet; + ipv4_t ipv4; + ipv4_option_t ipv4_option; + mri_t mri; + switch_t[MAX_HOPS] swids; +} + +error { IPHeaderTooShort } + +/************************************************************************* +*********************** P A R S E R *********************************** +*************************************************************************/ + +parser ParserImpl(packet_in packet, +out headers hdr, +inout metadata meta, +inout standard_metadata_t standard_metadata) { + + state start { + transition parse_ethernet; + } + + state parse_ethernet { + packet.extract(hdr.ethernet); + transition select(hdr.ethernet.etherType) { + TYPE_IPV4: parse_ipv4; + default: accept; + } + } + + state parse_ipv4 { + packet.extract(hdr.ipv4); + verify(hdr.ipv4.ihl >= 5, error.IPHeaderTooShort); + transition select(hdr.ipv4.ihl) { + 5 : accept; + default : parse_ipv4_option; + } + } + + state parse_ipv4_option { + packet.extract(hdr.ipv4_option); + transition select(hdr.ipv4_option.option) { + IPV4_OPTION_MRI: parse_mri; + default: accept; + } + } + + state parse_mri { + packet.extract(hdr.mri); + meta.parser_metadata.remaining = hdr.mri.count; + transition select(meta.parser_metadata.remaining) { + 0 : accept; + default: parse_swid; + } + } + + state parse_swid { + packet.extract(hdr.swids.next); + meta.parser_metadata.remaining = meta.parser_metadata.remaining - 1; + transition select(meta.parser_metadata.remaining) { + 0 : accept; + default: parse_swid; + } + } +} + + +/************************************************************************* +************ C H E C K S U M V E R I F I C A T I O N ************* +*************************************************************************/ + +control verifyChecksum(in headers hdr, inout metadata meta) { + apply { } +} + + +/************************************************************************* +************** I N G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + action drop() { + mark_to_drop(); + } + + action add_mri_option() { + hdr.ipv4_option.setValid(); + hdr.ipv4_option.copyFlag = 1; + hdr.ipv4_option.optClass = 2; /* Debugging and Measurement */ + hdr.ipv4_option.option = IPV4_OPTION_MRI; + hdr.ipv4_option.optionLength = 4; /* sizeof(ipv4_option) + sizeof(mri) */ + + hdr.mri.setValid(); + hdr.mri.count = 0; + hdr.ipv4.ihl = hdr.ipv4.ihl + 1; + } + + action add_swid(switchID_t id) { + hdr.mri.count = hdr.mri.count + 1; + hdr.swids.push_front(1); + hdr.swids[0].swid = id; + + hdr.ipv4.ihl = hdr.ipv4.ihl + 1; + hdr.ipv4_option.optionLength = hdr.ipv4_option.optionLength + 4; + } + + action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) { + standard_metadata.egress_spec = port; + hdr.ethernet.srcAddr = hdr.ethernet.dstAddr; + hdr.ethernet.dstAddr = dstAddr; + hdr.ipv4.ttl = hdr.ipv4.ttl - 1; + } + + table swid { + actions = { add_swid; NoAction; } + default_action = NoAction(); + } + + table ipv4_lpm { + key = { + hdr.ipv4.dstAddr: lpm; + } + actions = { + ipv4_forward; + drop; + NoAction; + } + size = 1024; + default_action = NoAction(); + } + + apply { + if (hdr.ipv4.isValid()) { + ipv4_lpm.apply(); + + if (!hdr.mri.isValid()) { + add_mri_option(); + } + + swid.apply(); + } + } +} + +/************************************************************************* +**************** E G R E S S P R O C E S S I N G ******************* +*************************************************************************/ + +control egress(inout headers hdr, inout metadata meta, inout standard_metadata_t standard_metadata) { + apply { } +} + +/************************************************************************* +************* C H E C K S U M C O M P U T A T I O N ************** +*************************************************************************/ + + +control computeChecksum( +inout headers hdr, +inout metadata meta) +{ + Checksum16() ipv4_checksum; + + apply { + if (hdr.ipv4.isValid()) { + hdr.ipv4.hdrChecksum = ipv4_checksum.get( + { + hdr.ipv4.version, + hdr.ipv4.ihl, + hdr.ipv4.diffserv, + hdr.ipv4.totalLen, + hdr.ipv4.identification, + hdr.ipv4.flags, + hdr.ipv4.fragOffset, + hdr.ipv4.ttl, + hdr.ipv4.protocol, + hdr.ipv4.srcAddr, + hdr.ipv4.dstAddr + }); + } + } +} + +/************************************************************************* +*********************** D E P A R S E R ******************************* +*************************************************************************/ + +control DeparserImpl(packet_out packet, in headers hdr) { + apply { + packet.emit(hdr.ethernet); + packet.emit(hdr.ipv4); + packet.emit(hdr.ipv4_option); + packet.emit(hdr.mri); + packet.emit(hdr.swids); + } +} + +/************************************************************************* +*********************** S W I T C H ******************************* +*************************************************************************/ + +V1Switch( +ParserImpl(), +verifyChecksum(), +ingress(), +egress(), +computeChecksum(), +DeparserImpl() +) main; diff --git a/P4D2_2017/utils/mininet/appcontroller.py b/P4D2_2017/utils/mininet/appcontroller.py new file mode 100644 index 0000000..0989cce --- /dev/null +++ b/P4D2_2017/utils/mininet/appcontroller.py @@ -0,0 +1,103 @@ +import subprocess + +from shortest_path import ShortestPath + +class AppController: + + def __init__(self, manifest=None, target=None, topo=None, net=None, links=None): + self.manifest = manifest + self.target = target + self.conf = manifest['targets'][target] + self.topo = topo + self.net = net + self.links = links + + def read_entries(self, filename): + entries = [] + with open(filename, 'r') as f: + for line in f: + line = line.strip() + if line == '': continue + entries.append(line) + return entries + + def add_entries(self, thrift_port=9090, sw=None, entries=None): + assert entries + if sw: thrift_port = sw.thrift_port + + print '\n'.join(entries) + p = subprocess.Popen(['simple_switch_CLI', '--thrift-port', str(thrift_port)], stdin=subprocess.PIPE) + p.communicate(input='\n'.join(entries)) + + def read_register(self, register, idx, thrift_port=9090, sw=None): + if sw: thrift_port = sw.thrift_port + p = subprocess.Popen(['simple_switch_CLI', '--thrift-port', str(thrift_port)], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + stdout, stderr = p.communicate(input="register_read %s %d" % (register, idx)) + reg_val = filter(lambda l: ' %s[%d]' % (register, idx) in l, stdout.split('\n'))[0].split('= ', 1)[1] + return long(reg_val) + + def start(self): + shortestpath = ShortestPath(self.links) + entries = {} + for sw in self.topo.switches(): + entries[sw] = [] + if 'switches' in self.conf and sw in self.conf['switches'] and 'entries' in self.conf['switches'][sw]: + extra_entries = self.conf['switches'][sw]['entries'] + if type(extra_entries) == list: # array of entries + entries[sw] += extra_entries + else: # path to file that contains entries + entries[sw] += self.read_entries(extra_entries) + #entries[sw] += [ + # 'table_set_default send_frame _drop', + # 'table_set_default forward _drop', + # 'table_set_default ipv4_lpm _drop'] + + for host_name in self.topo._host_links: + h = self.net.get(host_name) + for link in self.topo._host_links[host_name].values(): + sw = link['sw'] + #entries[sw].append('table_add send_frame rewrite_mac %d => %s' % (link['sw_port'], link['sw_mac'])) + #entries[sw].append('table_add forward set_dmac %s => %s' % (link['host_ip'], link['host_mac'])) + #entries[sw].append('table_add ipv4_lpm set_nhop %s/32 => %s %d' % (link['host_ip'], link['host_ip'], link['sw_port'])) + iface = h.intfNames()[link['idx']] + # use mininet to set ip and mac to let it know the change + h.setIP(link['host_ip'], 16) + h.setMAC(link['host_mac']) + #h.cmd('ifconfig %s %s hw ether %s' % (iface, link['host_ip'], link['host_mac'])) + h.cmd('arp -i %s -s %s %s' % (iface, link['sw_ip'], link['sw_mac'])) + h.cmd('ethtool --offload %s rx off tx off' % iface) + h.cmd('ip route add %s dev %s' % (link['sw_ip'], iface)) + h.setDefaultRoute("via %s" % link['sw_ip']) + + for h in self.net.hosts: + h_link = self.topo._host_links[h.name].values()[0] + for sw in self.net.switches: + path = shortestpath.get(sw.name, h.name, exclude=lambda n: n[0]=='h') + if not path: continue + if not path[1][0] == 's': continue # next hop is a switch + sw_link = self.topo._sw_links[sw.name][path[1]] + #entries[sw.name].append('table_add send_frame rewrite_mac %d => %s' % (sw_link[0]['port'], sw_link[0]['mac'])) + #entries[sw.name].append('table_add forward set_dmac %s => %s' % (h_link['host_ip'], sw_link[1]['mac'])) + #entries[sw.name].append('table_add ipv4_lpm set_nhop %s/32 => %s %d' % (h_link['host_ip'], h_link['host_ip'], sw_link[0]['port'])) + + for h2 in self.net.hosts: + if h == h2: continue + path = shortestpath.get(h.name, h2.name, exclude=lambda n: n[0]=='h') + if not path: continue + h_link = self.topo._host_links[h.name][path[1]] + h2_link = self.topo._host_links[h2.name].values()[0] + h.cmd('ip route add %s via %s' % (h2_link['host_ip'], h_link['sw_ip'])) + + + print "**********" + print "Configuring entries in p4 tables" + for sw_name in entries: + print + print "Configuring switch... %s" % sw_name + sw = self.net.get(sw_name) + self.add_entries(sw=sw, entries=entries[sw_name]) + print "Configuration complete." + print "**********" + + def stop(self): + pass diff --git a/P4D2_2017/utils/mininet/apptopo.py b/P4D2_2017/utils/mininet/apptopo.py new file mode 100644 index 0000000..2976c9a --- /dev/null +++ b/P4D2_2017/utils/mininet/apptopo.py @@ -0,0 +1,69 @@ +from mininet.topo import Topo + +class AppTopo(Topo): + + def __init__(self, links, latencies={}, manifest=None, target=None, + log_dir="/tmp", **opts): + Topo.__init__(self, **opts) + + nodes = sum(map(list, zip(*links)), []) + host_names = sorted(list(set(filter(lambda n: n[0] == 'h', nodes)))) + sw_names = sorted(list(set(filter(lambda n: n[0] == 's', nodes)))) + sw_ports = dict([(sw, []) for sw in sw_names]) + + self._host_links = {} + self._sw_links = dict([(sw, {}) for sw in sw_names]) + + for sw_name in sw_names: + self.addSwitch(sw_name, log_file="%s/%s.log" %(log_dir, sw_name)) + + for host_name in host_names: + host_num = int(host_name[1:]) + + host_ip = "10.0.%d.10" % host_num + host_mac = '00:04:00:00:00:%02x' % host_num + + self.addHost(host_name) + + self._host_links[host_name] = {} + host_links = filter(lambda l: l[0]==host_name or l[1]==host_name, links) + + sw_idx = 0 + for link in host_links: + sw = link[0] if link[0] != host_name else link[1] + sw_num = int(sw[1:]) + assert sw[0]=='s', "Hosts should be connected to switches, not " + str(sw) + + delay_key = ''.join([host_name, sw]) + delay = latencies[delay_key] if delay_key in latencies else '0ms' + sw_ports[sw].append(host_name) + self._host_links[host_name][sw] = dict( + idx=sw_idx, + host_mac = host_mac, + host_ip = host_ip, + sw = sw, + sw_mac = "00:aa:00:%02x:00:%02x" % (sw_num, host_num), + sw_ip = "10.0.%d.%d" % (host_num, sw_idx+1), + sw_port = sw_ports[sw].index(host_name)+1 + ) + self.addLink(host_name, sw, delay=delay, + addr1=host_mac, addr2=self._host_links[host_name][sw]['sw_mac']) + sw_idx += 1 + + for link in links: # only check switch-switch links + sw1, sw2 = link + if sw1[0] != 's' or sw2[0] != 's': continue + + delay_key = ''.join(sorted([host_name, sw])) + delay = latencies[delay_key] if delay_key in latencies else '0ms' + self.addLink(sw1, sw2, delay=delay) + sw_ports[sw1].append(sw2) + sw_ports[sw2].append(sw1) + + sw1_num, sw2_num = int(sw1[1:]), int(sw2[1:]) + sw1_port = dict(mac="00:aa:00:%02x:%02x:00" % (sw1_num, sw2_num), port=sw_ports[sw1].index(sw2)+1) + sw2_port = dict(mac="00:aa:00:%02x:%02x:00" % (sw2_num, sw1_num), port=sw_ports[sw2].index(sw1)+1) + + self._sw_links[sw1][sw2] = [sw1_port, sw2_port] + self._sw_links[sw2][sw1] = [sw2_port, sw1_port] + diff --git a/P4D2_2017/utils/mininet/multi_switch_mininet.py b/P4D2_2017/utils/mininet/multi_switch_mininet.py new file mode 100755 index 0000000..497980d --- /dev/null +++ b/P4D2_2017/utils/mininet/multi_switch_mininet.py @@ -0,0 +1,242 @@ +#!/usr/bin/env python2 + +# Copyright 2013-present Barefoot Networks, Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +import signal +import os +import sys +import subprocess +import argparse +import json +import importlib +import re +from time import sleep + +from mininet.net import Mininet +from mininet.topo import Topo +from mininet.link import TCLink +from mininet.log import setLogLevel, info +from mininet.cli import CLI + +from p4_mininet import P4Switch, P4Host +import apptopo +import appcontroller + +parser = argparse.ArgumentParser(description='Mininet demo') +parser.add_argument('--behavioral-exe', help='Path to behavioral executable', + type=str, action="store", required=True) +parser.add_argument('--thrift-port', help='Thrift server port for table updates', + type=int, action="store", default=9090) +parser.add_argument('--bmv2-log', help='verbose messages in log file', action="store_true") +parser.add_argument('--cli', help="start the mininet cli", action="store_true") +parser.add_argument('--auto-control-plane', help='enable automatic control plane population', action="store_true") +parser.add_argument('--json', help='Path to JSON config file', + type=str, action="store", required=True) +parser.add_argument('--pcap-dump', help='Dump packets on interfaces to pcap files', + action="store_true") +parser.add_argument('--manifest', '-m', help='Path to manifest file', + type=str, action="store", required=True) +parser.add_argument('--target', '-t', help='Target in manifest file to run', + type=str, action="store", required=True) +parser.add_argument('--log-dir', '-l', help='Location to save output to', + type=str, action="store", required=True) +parser.add_argument('--cli-message', help='Message to print before starting CLI', + type=str, action="store", required=False, default=False) + + +args = parser.parse_args() + + +next_thrift_port = args.thrift_port + +def run_command(command): + return os.WEXITSTATUS(os.system(command)) + +def configureP4Switch(**switch_args): + class ConfiguredP4Switch(P4Switch): + def __init__(self, *opts, **kwargs): + global next_thrift_port + kwargs.update(switch_args) + kwargs['thrift_port'] = next_thrift_port + next_thrift_port += 1 + P4Switch.__init__(self, *opts, **kwargs) + return ConfiguredP4Switch + + +def main(): + + with open(args.manifest, 'r') as f: + manifest = json.load(f) + + conf = manifest['targets'][args.target] + params = conf['parameters'] if 'parameters' in conf else {} + + os.environ.update(dict(map(lambda (k,v): (k, str(v)), params.iteritems()))) + + def formatParams(s): + for param in params: + s = re.sub('\$'+param+'(\W|$)', str(params[param]) + r'\1', s) + s = s.replace('${'+param+'}', str(params[param])) + return s + + AppTopo = apptopo.AppTopo + AppController = appcontroller.AppController + + if 'topo_module' in conf: + sys.path.insert(0, os.path.dirname(args.manifest)) + topo_module = importlib.import_module(conf['topo_module']) + AppTopo = topo_module.CustomAppTopo + + if 'controller_module' in conf: + sys.path.insert(0, os.path.dirname(args.manifest)) + controller_module = importlib.import_module(conf['controller_module']) + AppController = controller_module.CustomAppController + + if not os.path.isdir(args.log_dir): + if os.path.exists(args.log_dir): raise Exception('Log dir exists and is not a dir') + os.mkdir(args.log_dir) + os.environ['P4APP_LOGDIR'] = args.log_dir + + + links = [l[:2] for l in conf['links']] + latencies = dict([(''.join(sorted(l[:2])), l[2]) for l in conf['links'] if len(l)==3]) + + for host_name in sorted(conf['hosts'].keys()): + host = conf['hosts'][host_name] + if 'latency' not in host: continue + for a, b in links: + if a != host_name and b != host_name: continue + other = a if a != host_name else b + latencies[host_name+other] = host['latency'] + + for l in latencies: + if isinstance(latencies[l], (str, unicode)): + latencies[l] = formatParams(latencies[l]) + else: + latencies[l] = str(latencies[l]) + "ms" + + bmv2_log = args.bmv2_log or ('bmv2_log' in conf and conf['bmv2_log']) + pcap_dump = args.pcap_dump or ('pcap_dump' in conf and conf['pcap_dump']) + + topo = AppTopo(links, latencies, manifest=manifest, target=args.target, + log_dir=args.log_dir) + switchClass = configureP4Switch( + sw_path=args.behavioral_exe, + json_path=args.json, + log_console=bmv2_log, + pcap_dump=pcap_dump) + net = Mininet(topo = topo, + link = TCLink, + host = P4Host, + switch = switchClass, + controller = None) + net.start() + + sleep(1) + + controller = None + if args.auto_control_plane or 'controller_module' in conf: + controller = AppController(manifest=manifest, target=args.target, + topo=topo, net=net, links=links) + controller.start() + + + for h in net.hosts: + h.describe() + + if args.cli_message is not None: + with open(args.cli_message, 'r') as message_file: + print message_file.read() + + if args.cli or ('cli' in conf and conf['cli']): + CLI(net) + + stdout_files = dict() + return_codes = [] + host_procs = [] + + + def formatCmd(cmd): + for h in net.hosts: + cmd = cmd.replace(h.name, h.defaultIntf().updateIP()) + return cmd + + def _wait_for_exit(p, host): + print p.communicate() + if p.returncode is None: + p.wait() + print p.communicate() + return_codes.append(p.returncode) + if host_name in stdout_files: + stdout_files[host_name].flush() + stdout_files[host_name].close() + + print '\n'.join(map(lambda (k,v): "%s: %s"%(k,v), params.iteritems())) + '\n' + + for host_name in sorted(conf['hosts'].keys()): + host = conf['hosts'][host_name] + if 'cmd' not in host: continue + + h = net.get(host_name) + stdout_filename = os.path.join(args.log_dir, h.name + '.stdout') + stdout_files[h.name] = open(stdout_filename, 'w') + cmd = formatCmd(host['cmd']) + print h.name, cmd + p = h.popen(cmd, stdout=stdout_files[h.name], shell=True, preexec_fn=os.setpgrp) + if 'startup_sleep' in host: sleep(host['startup_sleep']) + + if 'wait' in host and host['wait']: + _wait_for_exit(p, host_name) + else: + host_procs.append((p, host_name)) + + for p, host_name in host_procs: + if 'wait' in conf['hosts'][host_name] and conf['hosts'][host_name]['wait']: + _wait_for_exit(p, host_name) + + + for p, host_name in host_procs: + if 'wait' in conf['hosts'][host_name] and conf['hosts'][host_name]['wait']: + continue + if p.returncode is None: + run_command('pkill -INT -P %d' % p.pid) + sleep(0.2) + rc = run_command('pkill -0 -P %d' % p.pid) # check if it's still running + if rc == 0: # the process group is still running, send TERM + sleep(1) # give it a little more time to exit gracefully + run_command('pkill -TERM -P %d' % p.pid) + _wait_for_exit(p, host_name) + + if 'after' in conf and 'cmd' in conf['after']: + cmds = conf['after']['cmd'] if type(conf['after']['cmd']) == list else [conf['after']['cmd']] + for cmd in cmds: + os.system(cmd) + + if controller: controller.stop() + + net.stop() + +# if bmv2_log: +# os.system('bash -c "cp /tmp/p4s.s*.log \'%s\'"' % args.log_dir) +# if pcap_dump: +# os.system('bash -c "cp *.pcap \'%s\'"' % args.log_dir) + + bad_codes = [rc for rc in return_codes if rc != 0] + if len(bad_codes): sys.exit(1) + +if __name__ == '__main__': + setLogLevel( 'info' ) + main() diff --git a/P4D2_2017/utils/mininet/p4_mininet.py b/P4D2_2017/utils/mininet/p4_mininet.py new file mode 100644 index 0000000..8abe79f --- /dev/null +++ b/P4D2_2017/utils/mininet/p4_mininet.py @@ -0,0 +1,161 @@ +# Copyright 2013-present Barefoot Networks, Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +from mininet.net import Mininet +from mininet.node import Switch, Host +from mininet.log import setLogLevel, info, error, debug +from mininet.moduledeps import pathCheck +from sys import exit +from time import sleep +import os +import tempfile +import socket + +class P4Host(Host): + def config(self, **params): + r = super(P4Host, self).config(**params) + + for off in ["rx", "tx", "sg"]: + cmd = "/sbin/ethtool --offload %s %s off" % (self.defaultIntf().name, off) + self.cmd(cmd) + + # disable IPv6 + self.cmd("sysctl -w net.ipv6.conf.all.disable_ipv6=1") + self.cmd("sysctl -w net.ipv6.conf.default.disable_ipv6=1") + self.cmd("sysctl -w net.ipv6.conf.lo.disable_ipv6=1") + + return r + + def describe(self, sw_addr=None, sw_mac=None): + print "**********" + print "Network configuration for: %s" % self.name + print "Default interface: %s\t%s\t%s" %( + self.defaultIntf().name, + self.defaultIntf().IP(), + self.defaultIntf().MAC() + ) + if sw_addr is not None or sw_mac is not None: + print "Default route to switch: %s (%s)" % (sw_addr, sw_mac) + print "**********" + +class P4Switch(Switch): + """P4 virtual switch""" + device_id = 0 + + def __init__(self, name, sw_path = None, json_path = None, + log_file = None, + thrift_port = None, + pcap_dump = False, + log_console = False, + verbose = False, + device_id = None, + enable_debugger = False, + **kwargs): + Switch.__init__(self, name, **kwargs) + assert(sw_path) + assert(json_path) + # make sure that the provided sw_path is valid + pathCheck(sw_path) + # make sure that the provided JSON file exists + if not os.path.isfile(json_path): + error("Invalid JSON file.\n") + exit(1) + self.sw_path = sw_path + self.json_path = json_path + self.verbose = verbose + self.log_file = log_file + if self.log_file is None: + self.log_file = "/tmp/p4s.{}.log".format(self.name) + self.output = open(self.log_file, 'w') + self.thrift_port = thrift_port + self.pcap_dump = pcap_dump + self.enable_debugger = enable_debugger + self.log_console = log_console + if device_id is not None: + self.device_id = device_id + P4Switch.device_id = max(P4Switch.device_id, device_id) + else: + self.device_id = P4Switch.device_id + P4Switch.device_id += 1 + self.nanomsg = "ipc:///tmp/bm-{}-log.ipc".format(self.device_id) + + @classmethod + def setup(cls): + pass + + def check_switch_started(self, pid): + """While the process is running (pid exists), we check if the Thrift + server has been started. If the Thrift server is ready, we assume that + the switch was started successfully. This is only reliable if the Thrift + server is started at the end of the init process""" + while True: + if not os.path.exists(os.path.join("/proc", str(pid))): + return False + sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) + sock.settimeout(0.5) + result = sock.connect_ex(("localhost", self.thrift_port)) + if result == 0: + return True + + def start(self, controllers): + "Start up a new P4 switch" + info("Starting P4 switch {}.\n".format(self.name)) + args = [self.sw_path] + for port, intf in self.intfs.items(): + if not intf.IP(): + args.extend(['-i', str(port) + "@" + intf.name]) + if self.pcap_dump: + args.append("--pcap") + # args.append("--useFiles") + if self.thrift_port: + args.extend(['--thrift-port', str(self.thrift_port)]) + if self.nanomsg: + args.extend(['--nanolog', self.nanomsg]) + args.extend(['--device-id', str(self.device_id)]) + P4Switch.device_id += 1 + args.append(self.json_path) + if self.enable_debugger: + args.append("--debugger") + if self.log_console: + args.append("--log-console") + info(' '.join(args) + "\n") + + pid = None + with tempfile.NamedTemporaryFile() as f: + # self.cmd(' '.join(args) + ' > /dev/null 2>&1 &') + self.cmd(' '.join(args) + ' >' + self.log_file + ' 2>&1 & echo $! >> ' + f.name) + pid = int(f.read()) + debug("P4 switch {} PID is {}.\n".format(self.name, pid)) + sleep(1) + if not self.check_switch_started(pid): + error("P4 switch {} did not start correctly." + "Check the switch log file.\n".format(self.name)) + exit(1) + info("P4 switch {} has been started.\n".format(self.name)) + + def stop(self): + "Terminate P4 switch." + self.output.flush() + self.cmd('kill %' + self.sw_path) + self.cmd('wait') + self.deleteIntfs() + + def attach(self, intf): + "Connect a data port" + assert(0) + + def detach(self, intf): + "Disconnect a data port" + assert(0) diff --git a/P4D2_2017/utils/mininet/shortest_path.py b/P4D2_2017/utils/mininet/shortest_path.py new file mode 100644 index 0000000..971b1b4 --- /dev/null +++ b/P4D2_2017/utils/mininet/shortest_path.py @@ -0,0 +1,78 @@ +class ShortestPath: + + def __init__(self, edges=[]): + self.neighbors = {} + for edge in edges: + self.addEdge(*edge) + + def addEdge(self, a, b): + if a not in self.neighbors: self.neighbors[a] = [] + if b not in self.neighbors[a]: self.neighbors[a].append(b) + + if b not in self.neighbors: self.neighbors[b] = [] + if a not in self.neighbors[b]: self.neighbors[b].append(a) + + def get(self, a, b, exclude=lambda node: False): + # Shortest path from a to b + return self._recPath(a, b, [], exclude) + + def _recPath(self, a, b, visited, exclude): + if a == b: return [a] + new_visited = visited + [a] + paths = [] + for neighbor in self.neighbors[a]: + if neighbor in new_visited: continue + if exclude(neighbor) and neighbor != b: continue + path = self._recPath(neighbor, b, new_visited, exclude) + if path: paths.append(path) + + paths.sort(key=len) + return [a] + paths[0] if len(paths) else None + +if __name__ == '__main__': + + edges = [ + (1, 2), + (1, 3), + (1, 5), + (2, 4), + (3, 4), + (3, 5), + (3, 6), + (4, 6), + (5, 6), + (7, 8) + + ] + sp = ShortestPath(edges) + + assert sp.get(1, 1) == [1] + assert sp.get(2, 2) == [2] + + assert sp.get(1, 2) == [1, 2] + assert sp.get(2, 1) == [2, 1] + + assert sp.get(1, 3) == [1, 3] + assert sp.get(3, 1) == [3, 1] + + assert sp.get(4, 6) == [4, 6] + assert sp.get(6, 4) == [6, 4] + + assert sp.get(2, 6) == [2, 4, 6] + assert sp.get(6, 2) == [6, 4, 2] + + assert sp.get(1, 6) in [[1, 3, 6], [1, 5, 6]] + assert sp.get(6, 1) in [[6, 3, 1], [6, 5, 1]] + + assert sp.get(2, 5) == [2, 1, 5] + assert sp.get(5, 2) == [5, 1, 2] + + assert sp.get(4, 5) in [[4, 3, 5], [4, 6, 5]] + assert sp.get(5, 4) in [[5, 3, 4], [6, 6, 4]] + + assert sp.get(7, 8) == [7, 8] + assert sp.get(8, 7) == [8, 7] + + assert sp.get(1, 7) == None + assert sp.get(7, 2) == None + diff --git a/P4D2_2017/utils/mininet/single_switch_mininet.py b/P4D2_2017/utils/mininet/single_switch_mininet.py new file mode 100755 index 0000000..e2e7636 --- /dev/null +++ b/P4D2_2017/utils/mininet/single_switch_mininet.py @@ -0,0 +1,133 @@ +#!/usr/bin/env python2 + +# Copyright 2013-present Barefoot Networks, Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +from mininet.net import Mininet +from mininet.topo import Topo +from mininet.log import setLogLevel, info +from mininet.cli import CLI + +from p4_mininet import P4Switch, P4Host + +import argparse +from subprocess import PIPE, Popen +from time import sleep + +parser = argparse.ArgumentParser(description='Mininet demo') +parser.add_argument('--behavioral-exe', help='Path to behavioral executable', + type=str, action="store", required=True) +parser.add_argument('--thrift-port', help='Thrift server port for table updates', + type=int, action="store", default=9090) +parser.add_argument('--num-hosts', help='Number of hosts to connect to switch', + type=int, action="store", default=2) +parser.add_argument('--mode', choices=['l2', 'l3'], type=str, default='l3') +parser.add_argument('--json', help='Path to JSON config file', + type=str, action="store", required=True) +parser.add_argument('--log-file', help='Path to write the switch log file', + type=str, action="store", required=False) +parser.add_argument('--pcap-dump', help='Dump packets on interfaces to pcap files', + type=str, action="store", required=False, default=False) +parser.add_argument('--switch-config', help='simple_switch_CLI script to configure switch', + type=str, action="store", required=False, default=False) +parser.add_argument('--cli-message', help='Message to print before starting CLI', + type=str, action="store", required=False, default=False) + +args = parser.parse_args() + + +class SingleSwitchTopo(Topo): + "Single switch connected to n (< 256) hosts." + def __init__(self, sw_path, json_path, log_file, + thrift_port, pcap_dump, n, **opts): + # Initialize topology and default options + Topo.__init__(self, **opts) + + switch = self.addSwitch('s1', + sw_path = sw_path, + json_path = json_path, + log_console = True, + log_file = log_file, + thrift_port = thrift_port, + enable_debugger = False, + pcap_dump = pcap_dump) + + for h in xrange(n): + host = self.addHost('h%d' % (h + 1), + ip = "10.0.%d.10/24" % h, + mac = '00:04:00:00:00:%02x' %h) + print "Adding host", str(host) + self.addLink(host, switch) + +def main(): + num_hosts = args.num_hosts + mode = args.mode + + topo = SingleSwitchTopo(args.behavioral_exe, + args.json, + args.log_file, + args.thrift_port, + args.pcap_dump, + num_hosts) + net = Mininet(topo = topo, + host = P4Host, + switch = P4Switch, + controller = None) + net.start() + + + sw_mac = ["00:aa:bb:00:00:%02x" % n for n in xrange(num_hosts)] + + sw_addr = ["10.0.%d.1" % n for n in xrange(num_hosts)] + + for n in xrange(num_hosts): + h = net.get('h%d' % (n + 1)) + if mode == "l2": + h.setDefaultRoute("dev %s" % h.defaultIntf().name) + else: + h.setARP(sw_addr[n], sw_mac[n]) + h.setDefaultRoute("dev %s via %s" % (h.defaultIntf().name, sw_addr[n])) + + for n in xrange(num_hosts): + h = net.get('h%d' % (n + 1)) + h.describe(sw_addr[n], sw_mac[n]) + + sleep(1) + + if args.switch_config is not None: + print + print "Reading switch configuration script:", args.switch_config + with open(args.switch_config, 'r') as config_file: + switch_config = config_file.read() + + print "Configuring switch..." + proc = Popen(["simple_switch_CLI"], stdin=PIPE) + proc.communicate(input=switch_config) + + print "Configuration complete." + print + + print "Ready !" + + if args.cli_message is not None: + with open(args.cli_message, 'r') as message_file: + print message_file.read() + + CLI( net ) + net.stop() + +if __name__ == '__main__': + setLogLevel( 'info' ) + main() diff --git a/P4D2_2017/utils/p4apprunner.py b/P4D2_2017/utils/p4apprunner.py new file mode 100755 index 0000000..36b9eea --- /dev/null +++ b/P4D2_2017/utils/p4apprunner.py @@ -0,0 +1,320 @@ +#!/usr/bin/env python2 +# Copyright 2013-present Barefoot Networks, Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +from __future__ import print_function + +import argparse +from collections import OrderedDict +import json +import os +import sys +import tarfile + +parser = argparse.ArgumentParser(description='p4apprunner') +parser.add_argument('--build-dir', help='Directory to build in.', + type=str, action='store', required=False, default='/tmp') +parser.add_argument('--quiet', help='Suppress log messages.', + action='store_true', required=False, default=False) +parser.add_argument('--manifest', help='Path to manifest file.', + type=str, action='store', required=False, default='./p4app.json') +parser.add_argument('app', help='.p4app package to run.', type=str) +parser.add_argument('target', help=('Target to run. Defaults to the first target ' + 'in the package.'), + nargs='?', type=str) + +args = parser.parse_args() + +def log(*items): + if args.quiet != True: + print(*items) + +def log_error(*items): + print(*items, file=sys.stderr) + +def run_command(command): + log('>', command) + return os.WEXITSTATUS(os.system(command)) + +class Manifest: + def __init__(self, program_file, language, target, target_config): + self.program_file = program_file + self.language = language + self.target = target + self.target_config = target_config + +def read_manifest(manifest_file): + manifest = json.load(manifest_file, object_pairs_hook=OrderedDict) + + if 'program' not in manifest: + log_error('No program defined in manifest.') + sys.exit(1) + program_file = manifest['program'] + + if 'language' not in manifest: + log_error('No language defined in manifest.') + sys.exit(1) + language = manifest['language'] + + if 'targets' not in manifest or len(manifest['targets']) < 1: + log_error('No targets defined in manifest.') + sys.exit(1) + + if args.target is not None: + chosen_target = args.target + elif 'default-target' in manifest: + chosen_target = manifest['default-target'] + else: + chosen_target = manifest['targets'].keys()[0] + + if chosen_target not in manifest['targets']: + log_error('Target not found in manifest:', chosen_target) + sys.exit(1) + + return Manifest(program_file, language, chosen_target, manifest['targets'][chosen_target]) + + +def run_compile_bmv2(manifest): + if 'run-before-compile' in manifest.target_config: + commands = manifest.target_config['run-before-compile'] + if not isinstance(commands, list): + log_error('run-before-compile should be a list:', commands) + sys.exit(1) + for command in commands: + run_command(command) + + compiler_args = [] + + if manifest.language == 'p4-14': + compiler_args.append('--p4v 14') + elif manifest.language == 'p4-16': + compiler_args.append('--p4v 16') + else: + log_error('Unknown language:', manifest.language) + sys.exit(1) + + if 'compiler-flags' in manifest.target_config: + flags = manifest.target_config['compiler-flags'] + if not isinstance(flags, list): + log_error('compiler-flags should be a list:', flags) + sys.exit(1) + compiler_args.extend(flags) + + # Compile the program. + output_file = manifest.program_file + '.json' + compiler_args.append('"%s"' % manifest.program_file) + compiler_args.append('-o "%s"' % output_file) + rv = run_command('p4c-bm2-ss %s' % ' '.join(compiler_args)) + + if 'run-after-compile' in manifest.target_config: + commands = manifest.target_config['run-after-compile'] + if not isinstance(commands, list): + log_error('run-after-compile should be a list:', commands) + sys.exit(1) + for command in commands: + run_command(command) + + if rv != 0: + log_error('Compile failed.') + sys.exit(1) + + return output_file + +def run_mininet(manifest): + output_file = run_compile_bmv2(manifest) + + # Run the program using the BMV2 Mininet simple switch. + switch_args = [] + + # We'll place the switch's log file in current (build) folder. + cwd = os.getcwd() + log_file = os.path.join(cwd, manifest.program_file + '.log') + print ("*** Log file %s" % log_file) + switch_args.append('--log-file "%s"' % log_file) + + pcap_dir = os.path.join(cwd) + print ("*** Pcap folder %s" % pcap_dir) + switch_args.append('--pcap-dump "%s" '% pcap_dir) + + # Generate a message that will be printed by the Mininet CLI to make + # interacting with the simple switch a little easier. + message_file = 'mininet_message.txt' + with open(message_file, 'w') as message: + + print(file=message) + print('======================================================================', + file=message) + print('Welcome to the BMV2 Mininet CLI!', file=message) + print('======================================================================', + file=message) + print('Your P4 program is installed into the BMV2 software switch', file=message) + print('and your initial configuration is loaded. You can interact', file=message) + print('with the network using the mininet CLI below.', file=message) + print(file=message) + print('To inspect or change the switch configuration, connect to', file=message) + print('its CLI from your host operating system using this command:', file=message) + print(' simple_switch_CLI', file=message) + print(file=message) + print('To view the switch log, run this command from your host OS:', file=message) + print(' tail -f %s' % log_file, file=message) + print(file=message) + print('To view the switch output pcap, check the pcap files in %s:' % pcap_dir, file=message) + print(' for example run: sudo tcpdump -xxx -r s1-eth1.pcap', file=message) + print(file=message) +# print('To run the switch debugger, run this command from your host OS:', file=message) +# print(' bm_p4dbg' , file=message) +# print(file=message) + + switch_args.append('--cli-message "%s"' % message_file) + + if 'num-hosts' in manifest.target_config: + switch_args.append('--num-hosts %s' % manifest.target_config['num-hosts']) + + if 'switch-config' in manifest.target_config: + switch_args.append('--switch-config "%s"' % manifest.target_config['switch-config']) + + switch_args.append('--behavioral-exe "%s"' % 'simple_switch') + switch_args.append('--json "%s"' % output_file) + + program = '"%s/mininet/single_switch_mininet.py"' % sys.path[0] + return run_command('python2 %s %s' % (program, ' '.join(switch_args))) + +def run_multiswitch(manifest): + output_file = run_compile_bmv2(manifest) + + script_args = [] + cwd = os.getcwd() + log_dir = os.path.join(cwd, cwd + '/logs') + print ("*** Log directory %s" % log_dir) + script_args.append('--log-dir "%s"' % log_dir) + pcap_dir = os.path.join(cwd) + print ("*** Pcap directory %s" % cwd) + script_args.append('--manifest "%s"' % args.manifest) + script_args.append('--target "%s"' % manifest.target) + if 'auto-control-plane' in manifest.target_config and manifest.target_config['auto-control-plane']: + script_args.append('--auto-control-plane' ) + script_args.append('--behavioral-exe "%s"' % 'simple_switch') + script_args.append('--json "%s"' % output_file) + #script_args.append('--cli') + + # Generate a message that will be printed by the Mininet CLI to make + # interacting with the simple switch a little easier. + message_file = 'mininet_message.txt' + with open(message_file, 'w') as message: + + print(file=message) + print('======================================================================', + file=message) + print('Welcome to the BMV2 Mininet CLI!', file=message) + print('======================================================================', + file=message) + print('Your P4 program is installed into the BMV2 software switch', file=message) + print('and your initial configuration is loaded. You can interact', file=message) + print('with the network using the mininet CLI below.', file=message) + print(file=message) + print('To inspect or change the switch configuration, connect to', file=message) + print('its CLI from your host operating system using this command:', file=message) + print(' simple_switch_CLI --thrift-port ', file=message) + print(file=message) + print('To view a switch log, run this command from your host OS:', file=message) + print(' tail -f %s/.log' % log_dir, file=message) + print(file=message) + print('To view the switch output pcap, check the pcap files in %s:' % pcap_dir, file=message) + print(' for example run: sudo tcpdump -xxx -r s1-eth1.pcap', file=message) + print(file=message) +# print('To run the switch debugger, run this command from your host OS:', file=message) +# print(' bm_p4dbg' , file=message) +# print(file=message) + + script_args.append('--cli-message "%s"' % message_file) + + program = '"%s/mininet/multi_switch_mininet.py"' % sys.path[0] + return run_command('python2 %s %s' % (program, ' '.join(script_args))) + +def run_stf(manifest): + output_file = run_compile_bmv2(manifest) + + if not 'test' in manifest.target_config: + log_error('No STF test file provided.') + sys.exit(1) + stf_file = manifest.target_config['test'] + + # Run the program using the BMV2 STF interpreter. + stf_args = [] + stf_args.append('-v') + stf_args.append(os.path.join(args.build_dir, output_file)) + stf_args.append(os.path.join(args.build_dir, stf_file)) + + program = '"%s/stf/bmv2stf.py"' % sys.path[0] + rv = run_command('python2 %s %s' % (program, ' '.join(stf_args))) + if rv != 0: + sys.exit(1) + return rv + +def run_custom(manifest): + output_file = run_compile_bmv2(manifest) + python_path = 'PYTHONPATH=$PYTHONPATH:/scripts/mininet/' + script_args = [] + script_args.append('--behavioral-exe "%s"' % 'simple_switch') + script_args.append('--json "%s"' % output_file) + script_args.append('--cli "%s"' % 'simple_switch_CLI') + if not 'program' in manifest.target_config: + log_error('No mininet program file provided.') + sys.exit(1) + program = manifest.target_config['program'] + rv = run_command('%s python2 %s %s' % (python_path, program, ' '.join(script_args))) + + if rv != 0: + sys.exit(1) + return rv + +def main(): + log('Entering build directory.') + os.chdir(args.build_dir) + + # A '.p4app' package is really just a '.tar.gz' archive. Extract it so we + # can process its contents. + log('Extracting package.') + tar = tarfile.open(args.app) + tar.extractall() + tar.close() + + log('Reading package manifest.') + with open(args.manifest, 'r') as manifest_file: + manifest = read_manifest(manifest_file) + + # Dispatch to the backend implementation for this target. + backend = manifest.target + if 'use' in manifest.target_config: + backend = manifest.target_config['use'] + + if backend == 'mininet': + rc = run_mininet(manifest) + elif backend == 'multiswitch': + rc = run_multiswitch(manifest) + elif backend == 'stf': + rc = run_stf(manifest) + elif backend == 'custom': + rc = run_custom(manifest) + elif backend == 'compile-bmv2': + run_compile_bmv2(manifest) + rc = 0 + else: + log_error('Target specifies unknown backend:', backend) + sys.exit(1) + + sys.exit(rc) + +if __name__ == '__main__': + main()