| /* |
| * 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; |
| } |
| } |
| } |
