diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:13:01 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:13:01 +0000 |
commit | 7adcb5b605cc1328a3084c334f4697ec9771936c (patch) | |
tree | 03e681bfda053978ba896745828e09cb056ad156 /print-bfd.c | |
parent | Initial commit. (diff) | |
download | tcpdump-upstream.tar.xz tcpdump-upstream.zip |
Adding upstream version 4.99.4.upstream/4.99.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | print-bfd.c | 426 |
1 files changed, 426 insertions, 0 deletions
diff --git a/print-bfd.c b/print-bfd.c new file mode 100644 index 0000000..8c04735 --- /dev/null +++ b/print-bfd.c @@ -0,0 +1,426 @@ +/* + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code + * distributions retain the above copyright notice and this paragraph + * in its entirety, and (2) distributions including binary code include + * the above copyright notice and this paragraph in its entirety in + * the documentation or other materials provided with the distribution. + * 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. + * + * Original code by Hannes Gredler (hannes@gredler.at) + */ + +/* \summary: Bidirectional Forwarding Detection (BFD) printer */ + +/* + * specification: draft-ietf-bfd-base-01 for version 0, + * RFC 5880 for version 1, and RFC 5881 + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "netdissect-stdinc.h" + +#define ND_LONGJMP_FROM_TCHECK +#include "netdissect.h" +#include "extract.h" + +#include "udp.h" + +/* + * Control packet, BFDv0, draft-ietf-bfd-base-01 + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |Vers | Diag |H|D|P|F|C|A|Rsv| Detect Mult | Length | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | My Discriminator | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Your Discriminator | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Desired Min TX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Required Min RX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Required Min Echo RX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + +/* + * Control packet, BFDv1, RFC 5880 + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |Vers | Diag |Sta|P|F|C|A|D|M| Detect Mult | Length | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | My Discriminator | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Your Discriminator | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Desired Min TX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Required Min RX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Required Min Echo RX Interval | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + +struct bfd_header_t { + nd_uint8_t version_diag; + nd_uint8_t flags; + nd_uint8_t detect_time_multiplier; + nd_uint8_t length; + nd_uint32_t my_discriminator; + nd_uint32_t your_discriminator; + nd_uint32_t desired_min_tx_interval; + nd_uint32_t required_min_rx_interval; + nd_uint32_t required_min_echo_interval; +}; + +/* + * An optional Authentication Header may be present + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Type | Auth Len | Authentication Data... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + +struct bfd_auth_header_t { + nd_uint8_t auth_type; + nd_uint8_t auth_len; + nd_uint8_t auth_data; + nd_uint8_t dummy; /* minimum 4 bytes */ +}; + +enum auth_type { + AUTH_PASSWORD = 1, + AUTH_MD5 = 2, + AUTH_MET_MD5 = 3, + AUTH_SHA1 = 4, + AUTH_MET_SHA1 = 5 +}; + +static const struct tok bfd_v1_authentication_values[] = { + { AUTH_PASSWORD, "Simple Password" }, + { AUTH_MD5, "Keyed MD5" }, + { AUTH_MET_MD5, "Meticulous Keyed MD5" }, + { AUTH_SHA1, "Keyed SHA1" }, + { AUTH_MET_SHA1, "Meticulous Keyed SHA1" }, + { 0, NULL } +}; + +enum auth_length { + AUTH_PASSWORD_FIELD_MIN_LEN = 4, /* header + password min: 3 + 1 */ + AUTH_PASSWORD_FIELD_MAX_LEN = 19, /* header + password max: 3 + 16 */ + AUTH_MD5_FIELD_LEN = 24, + AUTH_MD5_HASH_LEN = 16, + AUTH_SHA1_FIELD_LEN = 28, + AUTH_SHA1_HASH_LEN = 20 +}; + +#define BFD_EXTRACT_VERSION(x) (((x)&0xe0)>>5) +#define BFD_EXTRACT_DIAG(x) ((x)&0x1f) + +static const struct tok bfd_diag_values[] = { + { 0, "No Diagnostic" }, + { 1, "Control Detection Time Expired" }, + { 2, "Echo Function Failed" }, + { 3, "Neighbor Signaled Session Down" }, + { 4, "Forwarding Plane Reset" }, + { 5, "Path Down" }, + { 6, "Concatenated Path Down" }, + { 7, "Administratively Down" }, + { 8, "Reverse Concatenated Path Down" }, + { 0, NULL } +}; + +static const struct tok bfd_port_values[] = { + { BFD_CONTROL_PORT, "Control" }, + { BFD_MULTIHOP_PORT, "Multihop" }, + { BFD_LAG_PORT, "Lag" }, + { 0, NULL } +}; + +#define BFD_FLAG_AUTH 0x04 + +static const struct tok bfd_v0_flag_values[] = { + { 0x80, "I Hear You" }, + { 0x40, "Demand" }, + { 0x20, "Poll" }, + { 0x10, "Final" }, + { 0x08, "Control Plane Independent" }, + { BFD_FLAG_AUTH, "Authentication Present" }, + { 0x02, "Reserved" }, + { 0x01, "Reserved" }, + { 0, NULL } +}; + +static const struct tok bfd_v1_flag_values[] = { + { 0x20, "Poll" }, + { 0x10, "Final" }, + { 0x08, "Control Plane Independent" }, + { BFD_FLAG_AUTH, "Authentication Present" }, + { 0x02, "Demand" }, + { 0x01, "Multipoint" }, + { 0, NULL } +}; + +static const struct tok bfd_v1_state_values[] = { + { 0, "AdminDown" }, + { 1, "Down" }, + { 2, "Init" }, + { 3, "Up" }, + { 0, NULL } +}; + +static void +auth_print(netdissect_options *ndo, const u_char *pptr) +{ + const struct bfd_auth_header_t *bfd_auth_header; + uint8_t auth_type, auth_len; + int i; + + pptr += sizeof (struct bfd_header_t); + bfd_auth_header = (const struct bfd_auth_header_t *)pptr; + ND_TCHECK_SIZE(bfd_auth_header); + auth_type = GET_U_1(bfd_auth_header->auth_type); + auth_len = GET_U_1(bfd_auth_header->auth_len); + ND_PRINT("\n\tAuthentication: %s (%u), length: %u", + tok2str(bfd_v1_authentication_values,"Unknown",auth_type), + auth_type, auth_len); + pptr += 2; + ND_PRINT("\n\t Auth Key ID: %u", GET_U_1(pptr)); + + switch(auth_type) { + case AUTH_PASSWORD: +/* + * Simple Password Authentication Section Format + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Type | Auth Len | Auth Key ID | Password... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | ... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + if (auth_len < AUTH_PASSWORD_FIELD_MIN_LEN || + auth_len > AUTH_PASSWORD_FIELD_MAX_LEN) { + ND_PRINT("[invalid length %u]", + auth_len); + break; + } + pptr++; + ND_PRINT(", Password: "); + /* the length is equal to the password length plus three */ + (void)nd_printn(ndo, pptr, auth_len - 3, NULL); + break; + case AUTH_MD5: + case AUTH_MET_MD5: +/* + * Keyed MD5 and Meticulous Keyed MD5 Authentication Section Format + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Type | Auth Len | Auth Key ID | Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Sequence Number | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Key/Digest... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | ... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + if (auth_len != AUTH_MD5_FIELD_LEN) { + ND_PRINT("[invalid length %u]", + auth_len); + break; + } + pptr += 2; + ND_PRINT(", Sequence Number: 0x%08x", GET_BE_U_4(pptr)); + pptr += 4; + ND_TCHECK_LEN(pptr, AUTH_MD5_HASH_LEN); + ND_PRINT("\n\t Digest: "); + for(i = 0; i < AUTH_MD5_HASH_LEN; i++) + ND_PRINT("%02x", GET_U_1(pptr + i)); + break; + case AUTH_SHA1: + case AUTH_MET_SHA1: +/* + * Keyed SHA1 and Meticulous Keyed SHA1 Authentication Section Format + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Type | Auth Len | Auth Key ID | Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Sequence Number | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Auth Key/Hash... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | ... | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + if (auth_len != AUTH_SHA1_FIELD_LEN) { + ND_PRINT("[invalid length %u]", + auth_len); + break; + } + pptr += 2; + ND_PRINT(", Sequence Number: 0x%08x", GET_BE_U_4(pptr)); + pptr += 4; + ND_TCHECK_LEN(pptr, AUTH_SHA1_HASH_LEN); + ND_PRINT("\n\t Hash: "); + for(i = 0; i < AUTH_SHA1_HASH_LEN; i++) + ND_PRINT("%02x", GET_U_1(pptr + i)); + break; + } +} + +void +bfd_print(netdissect_options *ndo, const u_char *pptr, + u_int len, u_int port) +{ + ndo->ndo_protocol = "bfd"; + if (port == BFD_CONTROL_PORT || + port == BFD_MULTIHOP_PORT || + port == BFD_LAG_PORT) { + /* + * Control packet. + */ + const struct bfd_header_t *bfd_header; + uint8_t version_diag; + uint8_t version = 0; + uint8_t flags; + + bfd_header = (const struct bfd_header_t *)pptr; + ND_TCHECK_SIZE(bfd_header); + version_diag = GET_U_1(bfd_header->version_diag); + version = BFD_EXTRACT_VERSION(version_diag); + flags = GET_U_1(bfd_header->flags); + + switch (version) { + + /* BFDv0 */ + case 0: + if (ndo->ndo_vflag < 1) + { + ND_PRINT("BFDv0, Control, Flags: [%s], length: %u", + bittok2str(bfd_v0_flag_values, "none", flags), + len); + return; + } + + ND_PRINT("BFDv0, length: %u\n\tControl, Flags: [%s], Diagnostic: %s (0x%02x)", + len, + bittok2str(bfd_v0_flag_values, "none", flags), + tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(version_diag)), + BFD_EXTRACT_DIAG(version_diag)); + + ND_PRINT("\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u", + GET_U_1(bfd_header->detect_time_multiplier), + GET_U_1(bfd_header->detect_time_multiplier) * GET_BE_U_4(bfd_header->desired_min_tx_interval)/1000, + GET_U_1(bfd_header->length)); + + + ND_PRINT("\n\tMy Discriminator: 0x%08x", + GET_BE_U_4(bfd_header->my_discriminator)); + ND_PRINT(", Your Discriminator: 0x%08x", + GET_BE_U_4(bfd_header->your_discriminator)); + ND_PRINT("\n\t Desired min Tx Interval: %4u ms", + GET_BE_U_4(bfd_header->desired_min_tx_interval)/1000); + ND_PRINT("\n\t Required min Rx Interval: %4u ms", + GET_BE_U_4(bfd_header->required_min_rx_interval)/1000); + ND_PRINT("\n\t Required min Echo Interval: %4u ms", + GET_BE_U_4(bfd_header->required_min_echo_interval)/1000); + + if (flags & BFD_FLAG_AUTH) { + auth_print(ndo, pptr); + } + break; + + /* BFDv1 */ + case 1: + if (ndo->ndo_vflag < 1) + { + ND_PRINT("BFDv1, %s, State %s, Flags: [%s], length: %u", + tok2str(bfd_port_values, "unknown (%u)", port), + tok2str(bfd_v1_state_values, "unknown (%u)", (flags & 0xc0) >> 6), + bittok2str(bfd_v1_flag_values, "none", flags & 0x3f), + len); + return; + } + + ND_PRINT("BFDv1, length: %u\n\t%s, State %s, Flags: [%s], Diagnostic: %s (0x%02x)", + len, + tok2str(bfd_port_values, "unknown (%u)", port), + tok2str(bfd_v1_state_values, "unknown (%u)", (flags & 0xc0) >> 6), + bittok2str(bfd_v1_flag_values, "none", flags & 0x3f), + tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(version_diag)), + BFD_EXTRACT_DIAG(version_diag)); + + ND_PRINT("\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u", + GET_U_1(bfd_header->detect_time_multiplier), + GET_U_1(bfd_header->detect_time_multiplier) * GET_BE_U_4(bfd_header->desired_min_tx_interval)/1000, + GET_U_1(bfd_header->length)); + + + ND_PRINT("\n\tMy Discriminator: 0x%08x", + GET_BE_U_4(bfd_header->my_discriminator)); + ND_PRINT(", Your Discriminator: 0x%08x", + GET_BE_U_4(bfd_header->your_discriminator)); + ND_PRINT("\n\t Desired min Tx Interval: %4u ms", + GET_BE_U_4(bfd_header->desired_min_tx_interval)/1000); + ND_PRINT("\n\t Required min Rx Interval: %4u ms", + GET_BE_U_4(bfd_header->required_min_rx_interval)/1000); + ND_PRINT("\n\t Required min Echo Interval: %4u ms", + GET_BE_U_4(bfd_header->required_min_echo_interval)/1000); + + if (flags & BFD_FLAG_AUTH) { + auth_print(ndo, pptr); + } + break; + + default: + ND_PRINT("BFDv%u, Control, length: %u", + version, + len); + if (ndo->ndo_vflag >= 1) { + if(!print_unknown_data(ndo, pptr,"\n\t",len)) + return; + } + break; + } + } else if (port == BFD_ECHO_PORT) { + /* + * Echo packet. + */ + ND_PRINT("BFD, Echo, length: %u", + len); + if (ndo->ndo_vflag >= 1) { + if(!print_unknown_data(ndo, pptr,"\n\t",len)) + return; + } + } else { + /* + * Unknown packet type. + */ + ND_PRINT("BFD, unknown (%u), length: %u", + port, + len); + if (ndo->ndo_vflag >= 1) { + if(!print_unknown_data(ndo, pptr,"\n\t",len)) + return; + } + } +} |