From 66a5b93dee386bc2f57033a150341752923b8b41 Mon Sep 17 00:00:00 2001
From: Gerard Garcia <ggarcia@deic.uab.cat>
Date: Tue, 14 Jun 2016 16:45:44 +0200
Subject: [PATCH 13/13] Add printing support for vsockmon devices.
Print Linux 4.12 vsockmon captures:
# modprobe vsockmon
# ip link add type vsockmon
# ip link set vsockmon0 up
# tcpdump -i vsockmon0
16:25:24.987917 VIRTIO 3.1025 > 2.1234 CONNECT, length 76
16:25:24.987963 VIRTIO 2.1234 > 3.1025 CONNECT, length 76
16:25:26.568271 VIRTIO 3.1025 > 2.1234 PAYLOAD, length 82
16:25:26.568512 VIRTIO 2.1234 > 3.1025 CONTROL, length 76
16:25:28.411335 VIRTIO 3.1025 > 2.1234 DISCONNECT, length 76
16:25:28.411628 VIRTIO 2.1234 > 3.1025 DISCONNECT, length 76
For more information about vsock see:
http://wiki.qemu.org/Features/VirtioVsock
---
Makefile.in | 1 +
netdissect.h | 1 +
print-vsock.c | 243 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
print.c | 3 +
4 files changed, 248 insertions(+)
create mode 100644 print-vsock.c
diff --git a/Makefile.in b/Makefile.in
index 0941f0e..a301878 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -226,6 +226,7 @@ LIBNETDISSECT_SRC=\
print-vjc.c \
print-vqp.c \
print-vrrp.c \
+ print-vsock.c \
print-vtp.c \
print-vxlan.c \
print-vxlan-gpe.c \
diff --git a/netdissect.h b/netdissect.h
index 089b040..c89fcf1 100644
--- a/netdissect.h
+++ b/netdissect.h
@@ -444,6 +444,7 @@ extern u_int symantec_if_print IF_PRINTER_ARGS;
extern u_int token_if_print IF_PRINTER_ARGS;
extern u_int usb_linux_48_byte_print IF_PRINTER_ARGS;
extern u_int usb_linux_64_byte_print IF_PRINTER_ARGS;
+extern u_int vsock_print IF_PRINTER_ARGS;
/*
* Structure passed to some printers to allow them to print
diff --git a/print-vsock.c b/print-vsock.c
new file mode 100644
index 0000000..fc5694d
--- /dev/null
+++ b/print-vsock.c
@@ -0,0 +1,243 @@
+/*
+ * Copyright (c) 2016 Gerard Garcia <nouboh@gmail.com>
+ * Copyright (c) 2017 Red Hat, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. The names of the authors may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/* \summary: Linux vsock printer */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <netdissect-stdinc.h>
+#include <stddef.h>
+
+#include "netdissect.h"
+#include "extract.h"
+
+static const char tstr[] = " [|vsock]";
+
+enum af_vsockmon_transport {
+ AF_VSOCK_TRANSPORT_UNKNOWN = 0,
+ AF_VSOCK_TRANSPORT_NO_INFO = 1, /* No transport information */
+ AF_VSOCK_TRANSPORT_VIRTIO = 2, /* Virtio transport header */
+};
+
+static const struct tok vsock_transport[] = {
+ {AF_VSOCK_TRANSPORT_UNKNOWN, "UNKNOWN"},
+ {AF_VSOCK_TRANSPORT_NO_INFO, "NO_INFO"},
+ {AF_VSOCK_TRANSPORT_VIRTIO, "VIRTIO"},
+ { 0, NULL }
+};
+
+enum af_vsockmon_op {
+ AF_VSOCK_OP_UNKNOWN = 0,
+ AF_VSOCK_OP_CONNECT = 1,
+ AF_VSOCK_OP_DISCONNECT = 2,
+ AF_VSOCK_OP_CONTROL = 3,
+ AF_VSOCK_OP_PAYLOAD = 4,
+};
+
+static const struct tok vsock_op[] = {
+ {AF_VSOCK_OP_UNKNOWN, "UNKNOWN"},
+ {AF_VSOCK_OP_CONNECT, "CONNECT"},
+ {AF_VSOCK_OP_DISCONNECT, "DISCONNECT"},
+ {AF_VSOCK_OP_CONTROL, "CONTROL"},
+ {AF_VSOCK_OP_PAYLOAD, "PAYLOAD"},
+ { 0, NULL }
+};
+
+enum virtio_vsock_type {
+ VIRTIO_VSOCK_TYPE_STREAM = 1,
+};
+
+static const struct tok virtio_type[] = {
+ {VIRTIO_VSOCK_TYPE_STREAM, "STREAM"},
+ { 0, NULL }
+};
+
+enum virtio_vsock_op {
+ VIRTIO_VSOCK_OP_INVALID = 0,
+ VIRTIO_VSOCK_OP_REQUEST = 1,
+ VIRTIO_VSOCK_OP_RESPONSE = 2,
+ VIRTIO_VSOCK_OP_RST = 3,
+ VIRTIO_VSOCK_OP_SHUTDOWN = 4,
+ VIRTIO_VSOCK_OP_RW = 5,
+ VIRTIO_VSOCK_OP_CREDIT_UPDATE = 6,
+ VIRTIO_VSOCK_OP_CREDIT_REQUEST = 7,
+};
+
+static const struct tok virtio_op[] = {
+ {VIRTIO_VSOCK_OP_INVALID, "INVALID"},
+ {VIRTIO_VSOCK_OP_REQUEST, "REQUEST"},
+ {VIRTIO_VSOCK_OP_RESPONSE, "RESPONSE"},
+ {VIRTIO_VSOCK_OP_RST, "RST"},
+ {VIRTIO_VSOCK_OP_SHUTDOWN, "SHUTDOWN"},
+ {VIRTIO_VSOCK_OP_RW, "RW"},
+ {VIRTIO_VSOCK_OP_CREDIT_UPDATE, "CREDIT UPDATE"},
+ {VIRTIO_VSOCK_OP_CREDIT_REQUEST, "CREDIT REQUEST"},
+ { 0, NULL }
+};
+
+/* All fields are little-endian */
+
+struct virtio_vsock_hdr {
+ uint64_t src_cid;
+ uint64_t dst_cid;
+ uint32_t src_port;
+ uint32_t dst_port;
+ uint32_t len;
+ uint16_t type; /* enum virtio_vsock_type */
+ uint16_t op; /* enum virtio_vsock_op */
+ uint32_t flags;
+ uint32_t buf_alloc;
+ uint32_t fwd_cnt;
+} UNALIGNED;
+
+struct af_vsockmon_hdr {
+ uint64_t src_cid;
+ uint64_t dst_cid;
+ uint32_t src_port;
+ uint32_t dst_port;
+ uint16_t op; /* enum af_vsockmon_op */
+ uint16_t transport; /* enum af_vosckmon_transport */
+ uint16_t len; /* size of transport header */
+ uint8_t reserved[2];
+};
+
+static void
+vsock_virtio_hdr_print(netdissect_options *ndo, const struct virtio_vsock_hdr *hdr)
+{
+ uint16_t u16_v;
+ uint32_t u32_v;
+
+ u32_v = EXTRACT_LE_32BITS(&hdr->len);
+ ND_PRINT((ndo, "len %u", u32_v));
+
+ u16_v = EXTRACT_LE_16BITS(&hdr->type);
+ ND_PRINT((ndo, ", type %s",
+ tok2str(virtio_type, "Invalid type (%hu)", u16_v)));
+
+ u16_v = EXTRACT_LE_16BITS(&hdr->op);
+ ND_PRINT((ndo, ", op %s",
+ tok2str(virtio_op, "Invalid op (%hu)", u16_v)));
+
+ u32_v = EXTRACT_LE_32BITS(&hdr->flags);
+ ND_PRINT((ndo, ", flags %x", u32_v));
+
+ u32_v = EXTRACT_LE_32BITS(&hdr->buf_alloc);
+ ND_PRINT((ndo, ", buf_alloc %u", u32_v));
+
+ u32_v = EXTRACT_LE_32BITS(&hdr->fwd_cnt);
+ ND_PRINT((ndo, ", fwd_cnt %u", u32_v));
+}
+
+static size_t
+vsock_transport_hdr_size(uint16_t transport)
+{
+ switch (transport) {
+ case AF_VSOCK_TRANSPORT_VIRTIO:
+ return sizeof(struct virtio_vsock_hdr);
+ default:
+ return 0;
+ }
+}
+
+static void
+vsock_transport_hdr_print(netdissect_options *ndo, uint16_t transport,
+ const u_char *p, const u_int len)
+{
+ size_t transport_size = vsock_transport_hdr_size(transport);
+ const void *hdr;
+
+ if (len < sizeof(struct af_vsockmon_hdr) + transport_size)
+ return;
+
+ hdr = p + sizeof(struct af_vsockmon_hdr);
+ switch (transport) {
+ case AF_VSOCK_TRANSPORT_VIRTIO:
+ ND_PRINT((ndo, " ("));
+ vsock_virtio_hdr_print(ndo, hdr);
+ ND_PRINT((ndo, ")"));
+ break;
+ default:
+ break;
+ }
+}
+
+static void
+vsock_hdr_print(netdissect_options *ndo, const u_char *p, const u_int len)
+{
+ uint16_t hdr_transport, hdr_op;
+ uint32_t hdr_src_port, hdr_dst_port;
+ uint64_t hdr_src_cid, hdr_dst_cid;
+ size_t total_hdr_size;
+
+ const struct af_vsockmon_hdr *hdr = (struct af_vsockmon_hdr *)p;
+
+ hdr_transport = EXTRACT_LE_16BITS(&hdr->transport);
+ ND_PRINT((ndo, "%s",
+ tok2str(vsock_transport, "Invalid transport (%u)",
+ hdr_transport)));
+
+ /* If verbose level is more than 0 print transport details */
+ if (ndo->ndo_vflag) {
+ vsock_transport_hdr_print(ndo, hdr_transport, p, len);
+ ND_PRINT((ndo, "\n\t"));
+ } else
+ ND_PRINT((ndo, " "));
+
+ hdr_src_cid = EXTRACT_LE_64BITS(&hdr->src_cid);
+ hdr_dst_cid = EXTRACT_LE_64BITS(&hdr->dst_cid);
+ hdr_src_port = EXTRACT_LE_32BITS(&hdr->src_port);
+ hdr_dst_port = EXTRACT_LE_32BITS(&hdr->dst_port);
+ hdr_op = EXTRACT_LE_16BITS(&hdr->op);
+ ND_PRINT((ndo, "%lu.%hu > %lu.%hu %s, length %u",
+ hdr_src_cid, hdr_src_port,
+ hdr_dst_cid, hdr_dst_port,
+ tok2str(vsock_op, " invalid op (%u)", hdr_op),
+ len));
+
+ /* If debug level is more than 1 print payload contents */
+ total_hdr_size = sizeof(struct af_vsockmon_hdr) +
+ vsock_transport_hdr_size(hdr_transport);
+ if (ndo->ndo_vflag > 1 &&
+ hdr_op == AF_VSOCK_OP_PAYLOAD &&
+ len > total_hdr_size) {
+ const u_char *payload = p + total_hdr_size;
+
+ ND_PRINT((ndo, "\n"));
+ print_unknown_data(ndo, payload, "\t", len - total_hdr_size);
+ }
+}
+
+u_int
+vsock_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *cp)
+{
+ u_int len = h->len;
+
+ if (len < sizeof(struct af_vsockmon_hdr))
+ ND_PRINT((ndo, "%s", tstr));
+ else
+ vsock_hdr_print(ndo, cp, len);
+
+ return len;
+}
diff --git a/print.c b/print.c
index c76f344..1945cfd 100644
--- a/print.c
+++ b/print.c
@@ -220,6 +220,9 @@ static const struct printer printers[] = {
#ifdef DLT_PPP_SERIAL
{ ppp_hdlc_if_print, DLT_PPP_SERIAL },
#endif
+#ifdef DLT_VSOCK
+ { vsock_print, DLT_VSOCK },
+#endif
{ NULL, 0 },
};
--
2.13.5