diff options
Diffstat (limited to '')
| -rw-r--r-- | print-vsock.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/print-vsock.c b/print-vsock.c new file mode 100644 index 0000000..bb18c92 --- /dev/null +++ b/print-vsock.c @@ -0,0 +1,262 @@ +/* + * 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" + +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 { + nd_uint64_t src_cid; + nd_uint64_t dst_cid; + nd_uint32_t src_port; + nd_uint32_t dst_port; + nd_uint32_t len; + nd_uint16_t type; /* enum virtio_vsock_type */ + nd_uint16_t op; /* enum virtio_vsock_op */ + nd_uint32_t flags; + nd_uint32_t buf_alloc; + nd_uint32_t fwd_cnt; +}; + +struct af_vsockmon_hdr { + nd_uint64_t src_cid; + nd_uint64_t dst_cid; + nd_uint32_t src_port; + nd_uint32_t dst_port; + nd_uint16_t op; /* enum af_vsockmon_op */ + nd_uint16_t transport; /* enum af_vosckmon_transport */ + nd_uint16_t len; /* size of transport header */ + nd_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 = GET_LE_U_4(hdr->len); + ND_PRINT("len %u", u32_v); + + u16_v = GET_LE_U_2(hdr->type); + ND_PRINT(", type %s", + tok2str(virtio_type, "Invalid type (%hu)", u16_v)); + + u16_v = GET_LE_U_2(hdr->op); + ND_PRINT(", op %s", + tok2str(virtio_op, "Invalid op (%hu)", u16_v)); + + u32_v = GET_LE_U_4(hdr->flags); + ND_PRINT(", flags %x", u32_v); + + u32_v = GET_LE_U_4(hdr->buf_alloc); + ND_PRINT(", buf_alloc %u", u32_v); + + u32_v = GET_LE_U_4(hdr->fwd_cnt); + ND_PRINT(", fwd_cnt %u", u32_v); +} + +/* + * This size had better fit in a u_int. + */ +static u_int +vsock_transport_hdr_size(uint16_t transport) +{ + switch (transport) { + case AF_VSOCK_TRANSPORT_VIRTIO: + return (u_int)sizeof(struct virtio_vsock_hdr); + default: + return 0; + } +} + +/* Returns 0 on success, -1 on truncation */ +static int +vsock_transport_hdr_print(netdissect_options *ndo, uint16_t transport, + const u_char *p, const u_int caplen) +{ + u_int transport_size = vsock_transport_hdr_size(transport); + const void *hdr; + + if (caplen < sizeof(struct af_vsockmon_hdr) + transport_size) { + return -1; + } + + hdr = p + sizeof(struct af_vsockmon_hdr); + switch (transport) { + case AF_VSOCK_TRANSPORT_VIRTIO: + ND_PRINT(" ("); + vsock_virtio_hdr_print(ndo, hdr); + ND_PRINT(")"); + break; + default: + break; + } + return 0; +} + +static void +vsock_hdr_print(netdissect_options *ndo, const u_char *p, const u_int caplen) +{ + const struct af_vsockmon_hdr *hdr = (const struct af_vsockmon_hdr *)p; + uint16_t hdr_transport, hdr_op; + uint32_t hdr_src_port, hdr_dst_port; + uint64_t hdr_src_cid, hdr_dst_cid; + u_int total_hdr_size; + int ret = 0; + + hdr_transport = GET_LE_U_2(hdr->transport); + ND_PRINT("%s", + tok2str(vsock_transport, "Invalid transport (%u)", + hdr_transport)); + + /* If verbose level is more than 0 print transport details */ + if (ndo->ndo_vflag) { + ret = vsock_transport_hdr_print(ndo, hdr_transport, p, caplen); + if (ret == 0) + ND_PRINT("\n\t"); + } else + ND_PRINT(" "); + + hdr_src_cid = GET_LE_U_8(hdr->src_cid); + hdr_dst_cid = GET_LE_U_8(hdr->dst_cid); + hdr_src_port = GET_LE_U_4(hdr->src_port); + hdr_dst_port = GET_LE_U_4(hdr->dst_port); + hdr_op = GET_LE_U_2(hdr->op); + ND_PRINT("%" PRIu64 ".%u > %" PRIu64 ".%u %s, length %u", + hdr_src_cid, hdr_src_port, + hdr_dst_cid, hdr_dst_port, + tok2str(vsock_op, " invalid op (%u)", hdr_op), + caplen); + + if (ret < 0) + goto trunc; + + /* If debug level is more than 1 print payload contents */ + /* This size had better fit in a u_int */ + total_hdr_size = (u_int)sizeof(struct af_vsockmon_hdr) + + vsock_transport_hdr_size(hdr_transport); + if (ndo->ndo_vflag > 1 && hdr_op == AF_VSOCK_OP_PAYLOAD) { + if (caplen > total_hdr_size) { + const u_char *payload = p + total_hdr_size; + + ND_PRINT("\n"); + print_unknown_data(ndo, payload, "\t", + caplen - total_hdr_size); + } else + goto trunc; + } + return; + +trunc: + nd_print_trunc(ndo); +} + +void +vsock_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, + const u_char *cp) +{ + u_int caplen = h->caplen; + + ndo->ndo_protocol = "vsock"; + + if (caplen < sizeof(struct af_vsockmon_hdr)) { + nd_print_trunc(ndo); + ndo->ndo_ll_hdr_len += caplen; + return; + } + ndo->ndo_ll_hdr_len += sizeof(struct af_vsockmon_hdr); + vsock_hdr_print(ndo, cp, caplen); +} |