Add support for raw + af_packet sockets

.github/workflows/linux.yml

@@ -35,7 +35,8 @@ jobs:
       - name: Build linux tests
         run: |
           mkdir -p build/port
-          make
+          make EXTRA_CFLAGS="-DWOLFIP_RAWSOCKETS=1 -DWOLFIP_PACKET_SOCKETS=1"
+          make EXTRA_CFLAGS="-DWOLFIP_RAWSOCKETS=1 -DWOLFIP_PACKET_SOCKETS=1" build/raw_ping build/packet_ping
 
       - name: Run standalone "event loop" test
         timeout-minutes: 5
@@ -102,6 +103,18 @@ jobs:
           set -euo pipefail
           timeout --preserve-status 2m sudo LD_PRELOAD=$PWD/libwolfip.so ping -4 -n -c 5 127.0.0.1
 
+      - name: Testing raw sockets with raw_ping
+        timeout-minutes: 2
+        run: |
+          set -euo pipefail
+          timeout --preserve-status 2m sudo ./build/raw_ping 10.10.10.1
+
+      - name: Testing packet sockets with packet_ping
+        timeout-minutes: 2
+        run: |
+          set -euo pipefail
+          timeout --preserve-status 2m sudo ./build/packet_ping wtcp0 10.10.10.1
+
       - name: Install check
         run: |
           sudo apt-get install -y check

Makefile

@@ -1,6 +1,7 @@
 CC?=gcc
 CFLAGS:=-Wall -Werror -Wextra -I. -D_GNU_SOURCE
 CFLAGS+=-g -ggdb -Wdeclaration-after-statement
+EXTRA_CFLAGS?=
 CFLAGS+=$(EXTRA_CFLAGS)
 LDFLAGS+=-pthread
 # additional debug flags:
@@ -158,7 +159,8 @@ endif
 EXE=build/tcpecho build/tcp_netcat_poll build/tcp_netcat_select \
 	build/test-evloop build/test-dns build/test-wolfssl-forwarding \
 	build/test-ttl-expired build/test-wolfssl build/test-httpd \
-	build/ipfilter-logger build/test-esp build/esp-server
+	build/ipfilter-logger \
+	build/test-esp build/esp-server
 ifeq ($(UNAME_S),Linux)
   EXE+= build/test-evloop-tun
 endif
@@ -254,6 +256,14 @@ build/tcp_netcat_select: $(OBJ) build/port/posix/bsd_socket.o build/test/tcp_net
 	@echo "[LD] $@"
 	@$(CC) $(CFLAGS) -o $@ $(BEGIN_GROUP) $(^) $(LDFLAGS) $(END_GROUP)
 
+build/raw_ping: $(OBJ) build/port/posix/bsd_socket.o build/test/raw_ping.o
+	@echo "[LD] $@"
+	@$(CC) $(CFLAGS) -o $@ $(BEGIN_GROUP) $(^) $(LDFLAGS) $(END_GROUP)
+
+build/packet_ping: $(OBJ) build/port/posix/bsd_socket.o build/test/packet_ping.o
+	@echo "[LD] $@"
+	@$(CC) $(CFLAGS) -o $@ $(BEGIN_GROUP) $(^) $(LDFLAGS) $(END_GROUP)
+
 
 build/test-wolfssl:CFLAGS+=-Wno-cpp -DWOLFSSL_DEBUG -DWOLFSSL_WOLFIP
 build/test-httpd:CFLAGS+=-Wno-cpp -DWOLFSSL_DEBUG -DWOLFSSL_WOLFIP -Isrc/http

README.md

@@ -18,6 +18,18 @@ configured to forward traffic between multiple network interfaces.
 - Multi-interface support
 - Optional IPv4-forwarding
 
+## Supported socket types
+
+wolfIP exposes a BSD-like `socket(2)` API for IPv4 sockets:
+
+| Domain | Type | Protocol | Notes |
+|--------|------|----------|-------|
+| `AF_INET` | `SOCK_STREAM` / `IPSTACK_SOCK_STREAM` | TCP | Connection-oriented TCP sockets |
+| `AF_INET` | `SOCK_DGRAM` / `IPSTACK_SOCK_DGRAM` | UDP, or `0` | UDP datagram sockets |
+| `AF_INET` | `SOCK_DGRAM` / `IPSTACK_SOCK_DGRAM` | ICMP | ICMP datagram sockets, used for ping-style traffic |
+| `AF_INET` | `SOCK_RAW` / `IPSTACK_SOCK_RAW` | IP protocol number | IPv4 raw sockets when `WOLFIP_RAWSOCKETS` is enabled |
+| `AF_PACKET` | `SOCK_RAW` / `IPSTACK_SOCK_RAW` | Ethernet protocol number | Link-layer packet sockets when `WOLFIP_PACKET_SOCKETS` is enabled |
+
 ## Protocols and RFCs
 
 | Layer | Protocol | Features | RFC(s) |

config.h

@@ -35,6 +35,28 @@
 #define WOLFIP_MAX_INTERFACES 2
 #endif
 
+#ifndef WOLFIP_RAWSOCKETS
+#define WOLFIP_RAWSOCKETS 0
+#endif
+
+#ifndef WOLFIP_MAX_RAWSOCKETS
+#define WOLFIP_MAX_RAWSOCKETS 4
+#endif
+
+#ifndef WOLFIP_PACKET_SOCKETS
+#define WOLFIP_PACKET_SOCKETS 0
+#endif
+
+#if WOLFIP_PACKET_SOCKETS && !defined(ETHERNET)
+#undef WOLFIP_PACKET_SOCKETS
+#define WOLFIP_PACKET_SOCKETS 0
+#error "WOLFIP_PACKET_SOCKETS requires ETHERNET to be defined. Please adjust your configuration."
+#endif
+
+#ifndef WOLFIP_MAX_PACKETSOCKETS
+#define WOLFIP_MAX_PACKETSOCKETS 2
+#endif
+
 #ifndef WOLFIP_ENABLE_FORWARDING
 #define WOLFIP_ENABLE_FORWARDING 0
 #endif