Adding P4D2_2018_East Folder (#116)

* Copying P4D2 Fall 2017 into P4D2 2018 East.

* Updated P4D2_2018_East VM.  Added vagrant URL workaround, cdrom to VM.  Updated to latest commits of BMV2, p4c, PI.  Known issue with p4runtime exercise.

* Applied patch from @antoninbas in  and updated solution

P4D2_2018_East/exercises/basic/Makefile

@@ -0,0 +1 @@
+include ../../utils/Makefile

P4D2_2018_East/exercises/basic/README.md

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+# Implementing Basic Forwarding
+
+## Introduction
+
+The objective of this exercise is to write a P4 program that
+implements basic forwarding. To keep things simple, 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,
+`basic.p4`, which initially drops all packets. Your job will be to
+extend this skeleton program to properly forward IPv4 packets.
+
+Before that, let's compile the incomplete `basic.p4` and bring
+up a switch in Mininet to test its behavior.
+
+1. In your shell, run:
+   ```bash
+   make run
+   ```
+   This will:
+   * compile `basic.p4`, and
+   * start a Mininet instance with three switches (`s1`, `s2`, `s3`)
+     configured in a triangle, each connected to one host (`h1`, `h2`,
+     and `h3`).
+   * The hosts are assigned IPs of `10.0.1.1`, `10.0.2.2`, and `10.0.3.3`.
+
+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 to `h2`:
+   ```bash
+   ./send.py 10.0.2.2 "P4 is cool"
+   ```
+   The message will not be received.
+5. Type `exit` to leave each xterm and the Mininet command line.
+   Then, to stop mininet:
+   ```bash
+   make stop
+   ```
+   And to delete all pcaps, build files, and logs:
+   ```bash
+   make clean
+   ```
+
+The message was not received because each switch is programmed
+according to `basic.p4`, which drops all packets on arrival.
+Your job is to extend this file so it forwards packets.
+
+### A note about the control plane
+
+A P4 program defines a packet-processing pipeline, but the rules
+within each table are inserted 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, we have already implemented the the control plane
+logic for you. As part of bringing up the Mininet instance, the
+`make run` command 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 commands in the files
+`sX-commands.txt` 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 `basic.p4` file contains a skeleton P4 program with key pieces of
+logic replaced by `TODO` comments. Your implementation should follow
+the structure given in this file---replace each `TODO` with logic
+implementing the missing piece.
+
+A complete `basic.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`) that:
+	1. Sets the egress port for the next hop. 
+	2. Updates the ethernet destination address with the address of the next hop. 
+	3. Updates the ethernet source address with the address of the switch. 
+	4. Decrements 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`.
+    2. An `apply` block that applies the table.   
+6. **TODO:** A deparser that selects the order
+    in which fields inserted into the outgoing packet.
+7. 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 problems that might manifest as you develop your program:
+
+1. `basic.p4` might fail to compile. In this case, `make run` will
+report the error emitted from the compiler and halt.
+
+2. `basic.p4` might compile but fail to support the control plane
+rules in the `s1-commands.txt` through `s3-command.txt` files that
+`make run` tries to install using the Bmv2 CLI. In this case, `make run`
+will log the CLI tool output in the `logs` directory. Use these error 
+messages to fix your `basic.p4` implementation.
+
+3. `basic.p4` might compile, and the control plane rules might be
+installed, but the switch might not process packets in the desired
+way. The `/tmp/p4s.<switch-name>.log` files contain detailed logs
+that 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, `make run` may leave a Mininet instance
+running in the background. Use the following command to clean up
+these instances:
+
+```bash
+make stop
+```
+
+## Next Steps
+
+Congratulations, your implementation works! In the next exercise we
+will build on top of this and add support for a basic tunneling
+protocol: [basic_tunnel](../basic_tunnel)!
+

P4D2_2018_East/exercises/basic/basic.p4

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+/* -*- P4_16 -*- */
+#include <core.p4>
+#include <v1model.p4>
+
+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 MyParser(packet_in packet,
+                out headers hdr,
+                inout metadata meta,
+                inout standard_metadata_t standard_metadata) {
+
+    state start {
+        /* TODO: add parser logic */
+        transition accept;
+    }
+}
+
+
+/*************************************************************************
+************   C H E C K S U M    V E R I F I C A T I O N   *************
+*************************************************************************/
+
+control MyVerifyChecksum(inout headers hdr, inout metadata meta) {   
+    apply {  }
+}
+
+
+/*************************************************************************
+**************  I N G R E S S   P R O C E S S I N G   *******************
+*************************************************************************/
+
+control MyIngress(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) {
+        /* TODO: fill out code in action body */
+    }
+    
+    table ipv4_lpm {
+        key = {
+            hdr.ipv4.dstAddr: lpm;
+        }
+        actions = {
+            ipv4_forward;
+            drop;
+            NoAction;
+        }
+        size = 1024;
+        default_action = NoAction();
+    }
+    
+    apply {
+        /* TODO: fix ingress control logic
+         *  - ipv4_lpm should be applied only when IPv4 header is valid
+         */
+        ipv4_lpm.apply();
+    }
+}
+
+/*************************************************************************
+****************  E G R E S S   P R O C E S S I N G   *******************
+*************************************************************************/
+
+control MyEgress(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 MyComputeChecksum(inout headers hdr, inout metadata meta) {
+     apply {
+	update_checksum(
+	    hdr.ipv4.isValid(),
+            { 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 },
+            hdr.ipv4.hdrChecksum,
+            HashAlgorithm.csum16);
+    }
+}
+
+
+/*************************************************************************
+***********************  D E P A R S E R  *******************************
+*************************************************************************/
+
+control MyDeparser(packet_out packet, in headers hdr) {
+    apply {
+        /* TODO: add deparser logic */
+    }
+}
+
+/*************************************************************************
+***********************  S W I T C H  *******************************
+*************************************************************************/
+
+V1Switch(
+MyParser(),
+MyVerifyChecksum(),
+MyIngress(),
+MyEgress(),
+MyComputeChecksum(),
+MyDeparser()
+) main;

P4D2_2018_East/exercises/basic/receive.py

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+#!/usr/bin/env python
+import sys
+import struct
+import os
+
+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, TCP, 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):
+    if TCP in pkt and pkt[TCP].dport == 1234:
+        print "got a packet"
+        pkt.show2()
+    #    hexdump(pkt)
+        sys.stdout.flush()
+
+
+def main():
+    ifaces = filter(lambda i: 'eth' in i, os.listdir('/sys/class/net/'))
+    iface = ifaces[0]
+    print "sniffing on %s" % iface
+    sys.stdout.flush()
+    sniff(iface = iface,
+          prn = lambda x: handle_pkt(x))
+
+if __name__ == '__main__':
+    main()

P4D2_2018_East/exercises/basic/s1-commands.txt

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+table_set_default ipv4_lpm drop
+table_add ipv4_lpm ipv4_forward 10.0.1.1/32 => 00:00:00:00:01:01 1
+table_add ipv4_lpm ipv4_forward 10.0.2.2/32 => 00:00:00:02:02:00 2
+table_add ipv4_lpm ipv4_forward 10.0.3.3/32 => 00:00:00:03:03:00 3

P4D2_2018_East/exercises/basic/s2-commands.txt

@@ -0,0 +1,4 @@
+table_set_default ipv4_lpm drop
+table_add ipv4_lpm ipv4_forward 10.0.1.1/32 => 00:00:00:01:02:00 2
+table_add ipv4_lpm ipv4_forward 10.0.2.2/32 => 00:00:00:00:02:02 1
+table_add ipv4_lpm ipv4_forward 10.0.3.3/32 => 00:00:00:03:03:00 3

P4D2_2018_East/exercises/basic/s3-commands.txt

@@ -0,0 +1,4 @@
+table_set_default ipv4_lpm drop
+table_add ipv4_lpm ipv4_forward 10.0.1.1/32 => 00:00:00:01:03:00 2
+table_add ipv4_lpm ipv4_forward 10.0.2.2/32 => 00:00:00:02:03:00 3
+table_add ipv4_lpm ipv4_forward 10.0.3.3/32 => 00:00:00:00:03:03 1

P4D2_2018_East/exercises/basic/send.py

@@ -0,0 +1,41 @@
+#!/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, TCP
+
+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: <destination> "<message>"'
+        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')
+    pkt = pkt /IP(dst=addr) / TCP(dport=1234, sport=random.randint(49152,65535)) / sys.argv[2]
+    pkt.show2()
+    sendp(pkt, iface=iface, verbose=False)
+
+
+if __name__ == '__main__':
+    main()

P4D2_2018_East/exercises/basic/solution/basic.p4

@@ -0,0 +1,176 @@
+/* -*- P4_16 -*- */
+#include <core.p4>
+#include <v1model.p4>
+
+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 MyParser(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 MyVerifyChecksum(inout headers hdr, inout metadata meta) {   
+    apply {  }
+}
+
+
+/*************************************************************************
+**************  I N G R E S S   P R O C E S S I N G   *******************
+*************************************************************************/
+
+control MyIngress(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 MyEgress(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 MyComputeChecksum(inout headers  hdr, inout metadata meta) {
+     apply {
+	update_checksum(
+	    hdr.ipv4.isValid(),
+            { 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 },
+            hdr.ipv4.hdrChecksum,
+            HashAlgorithm.csum16);
+    }
+}
+
+/*************************************************************************
+***********************  D E P A R S E R  *******************************
+*************************************************************************/
+
+control MyDeparser(packet_out packet, in headers hdr) {
+    apply {
+        packet.emit(hdr.ethernet);
+        packet.emit(hdr.ipv4);
+    }
+}
+
+/*************************************************************************
+***********************  S W I T C H  *******************************
+*************************************************************************/
+
+V1Switch(
+MyParser(),
+MyVerifyChecksum(),
+MyIngress(),
+MyEgress(),
+MyComputeChecksum(),
+MyDeparser()
+) main;

P4D2_2018_East/exercises/basic/topology.json

@@ -0,0 +1,16 @@
+{
+    "hosts": [
+        "h1",
+        "h2",
+        "h3"
+    ],
+    "switches": {
+        "s1": { "cli_input" : "s1-commands.txt" },
+        "s2": { "cli_input" : "s2-commands.txt" },
+        "s3": { "cli_input" : "s3-commands.txt" }
+    },
+    "links": [
+        ["h1", "s1"], ["s1", "s2"], ["s1", "s3"], 
+        ["s3", "s2"], ["s2", "h2"], ["s3", "h3"]
+    ]
+}