X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/c62dff3187a3a4dd98e24d3bcb2a18aa3736bfd4..refs/heads/master:/print-pgm.c diff --git a/print-pgm.c b/print-pgm.c index 6926be23..d9c1e2c2 100644 --- a/print-pgm.c +++ b/print-pgm.c @@ -15,12 +15,43 @@ /* \summary: Pragmatic General Multicast (PGM) printer */ -#ifdef HAVE_CONFIG_H +/* specification: RFC 3208 + + Plus https://dl.acm.org/doi/pdf/10.1145/347057.347390 for PGMCC, + whence the ACK packet type comes; there are some I-Ds for PGMCC, + draft-ietf-rmt-bb-pgmcc-00 through draft-ietf-rmt-bb-pgmcc-03, + but none of them give any description of the packet-level + changes to PGM, unlike the paper in question, which merely gives + an *insufficient* description of said changes. In particular, + it doesn't indicate what the packet type code for ACK is. + + Luigi Rizzo's PGMCC code for FreeBSD, at + + https://web.archive.org/web/20020302084503/http://info.iet.unipi.it/~luigi/pgm-code/ + + uses 0x0b (11) for ACK. + + A capture file attached to + + https://gitlab.com/wireshark/wireshark/-/issues/4798 + + has packets that use 0x0d for ACK, as does the Wireshark dissector + for PGM, and as does OpenPGM at https://github.com/steve-o/openpgm. + It may be that some proprietary PGMCC implementations, such as + SmartPGM, do so as well. + + We use *both*, treating *either one* as a PGMCC ACK, pending + more information, such as an answer to + + https://github.com/steve-o/openpgm/issues/75. + + */ + #include -#endif #include "netdissect-stdinc.h" +#define ND_LONGJMP_FROM_TCHECK #include "netdissect.h" #include "extract.h" #include "addrtoname.h" @@ -95,17 +126,17 @@ struct pgm_data { }; typedef enum _pgm_type { - PGM_SPM = 0, /* source path message */ - PGM_POLL = 1, /* POLL Request */ - PGM_POLR = 2, /* POLL Response */ - PGM_ODATA = 4, /* original data */ - PGM_RDATA = 5, /* repair data */ - PGM_NAK = 8, /* NAK */ - PGM_NULLNAK = 9, /* Null NAK */ - PGM_NCF = 10, /* NAK Confirmation */ - PGM_ACK = 11, /* ACK for congestion control */ - PGM_SPMR = 12, /* SPM request */ - PGM_MAX = 255 + PGM_SPM = 0x00, /* source path message */ + PGM_POLL = 0x01, /* POLL Request */ + PGM_POLR = 0x02, /* POLL Response */ + PGM_ODATA = 0x04, /* original data */ + PGM_RDATA = 0x05, /* repair data */ + PGM_NAK = 0x08, /* NAK */ + PGM_NULLNAK = 0x09, /* Null NAK */ + PGM_NCF = 0x0a, /* NAK Confirmation */ + PGM_ACK = 0x0b, /* ACK for congestion control? */ + PGM_SPMR = 0x0c, /* SPM request */ + PGM_ACK2 = 0x0d, /* Also ACK for congestion control? */ } pgm_type; #define PGM_OPT_BIT_PRESENT 0x01 @@ -167,15 +198,14 @@ pgm_print(netdissect_options *ndo, if (!ND_TTEST_2(pgm->pgm_dport)) { if (ip6) { ND_PRINT("%s > %s:", - ip6addr_string(ndo, ip6->ip6_src), - ip6addr_string(ndo, ip6->ip6_dst)); + GET_IP6ADDR_STRING(ip6->ip6_src), + GET_IP6ADDR_STRING(ip6->ip6_dst)); } else { ND_PRINT("%s > %s:", - ipaddr_string(ndo, ip->ip_src), - ipaddr_string(ndo, ip->ip_dst)); + GET_IPADDR_STRING(ip->ip_src), + GET_IPADDR_STRING(ip->ip_dst)); } - nd_print_trunc(ndo); - return; + nd_trunc_longjmp(ndo); } sport = GET_BE_U_2(pgm->pgm_sport); @@ -184,9 +214,9 @@ pgm_print(netdissect_options *ndo, if (ip6) { if (GET_U_1(ip6->ip6_nxt) == IPPROTO_PGM) { ND_PRINT("%s.%s > %s.%s: ", - ip6addr_string(ndo, ip6->ip6_src), + GET_IP6ADDR_STRING(ip6->ip6_src), tcpport_string(ndo, sport), - ip6addr_string(ndo, ip6->ip6_dst), + GET_IP6ADDR_STRING(ip6->ip6_dst), tcpport_string(ndo, dport)); } else { ND_PRINT("%s > %s: ", @@ -195,9 +225,9 @@ pgm_print(netdissect_options *ndo, } else { if (GET_U_1(ip->ip_p) == IPPROTO_PGM) { ND_PRINT("%s.%s > %s.%s: ", - ipaddr_string(ndo, ip->ip_src), + GET_IPADDR_STRING(ip->ip_src), tcpport_string(ndo, sport), - ipaddr_string(ndo, ip->ip_dst), + GET_IPADDR_STRING(ip->ip_dst), tcpport_string(ndo, dport)); } else { ND_PRINT("%s > %s: ", @@ -220,28 +250,28 @@ pgm_print(netdissect_options *ndo, pgm->pgm_gsid[3], pgm->pgm_gsid[4], pgm->pgm_gsid[5]); + bp += sizeof(struct pgm_header); switch (pgm_type_val) { case PGM_SPM: { const struct pgm_spm *spm; - spm = (const struct pgm_spm *)(pgm + 1); + spm = (const struct pgm_spm *)bp; ND_TCHECK_SIZE(spm); - bp = (const u_char *) (spm + 1); + bp += sizeof(struct pgm_spm); switch (GET_BE_U_2(spm->pgms_nla_afi)) { - case AFNUM_INET: + case AFNUM_IP: ND_TCHECK_LEN(bp, sizeof(nd_ipv4)); addrtostr(bp, nla_buf, sizeof(nla_buf)); bp += sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: ND_TCHECK_LEN(bp, sizeof(nd_ipv6)); addrtostr6(bp, nla_buf, sizeof(nla_buf)); bp += sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } ND_PRINT("SPM seq %u trail %u lead %u nla %s", @@ -256,35 +286,31 @@ pgm_print(netdissect_options *ndo, const struct pgm_poll *pgm_poll; uint32_t ivl, rnd, mask; - pgm_poll = (const struct pgm_poll *)(pgm + 1); + pgm_poll = (const struct pgm_poll *)bp; ND_TCHECK_SIZE(pgm_poll); - bp = (const u_char *) (pgm_poll + 1); + bp += sizeof(struct pgm_poll); switch (GET_BE_U_2(pgm_poll->pgmp_nla_afi)) { - case AFNUM_INET: + case AFNUM_IP: ND_TCHECK_LEN(bp, sizeof(nd_ipv4)); addrtostr(bp, nla_buf, sizeof(nla_buf)); bp += sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: ND_TCHECK_LEN(bp, sizeof(nd_ipv6)); addrtostr6(bp, nla_buf, sizeof(nla_buf)); bp += sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } - ND_TCHECK_LEN(bp, sizeof(uint32_t)); ivl = GET_BE_U_4(bp); bp += sizeof(uint32_t); - ND_TCHECK_LEN(bp, sizeof(uint32_t)); rnd = GET_BE_U_4(bp); bp += sizeof(uint32_t); - ND_TCHECK_LEN(bp, sizeof(uint32_t)); mask = GET_BE_U_4(bp); bp += sizeof(uint32_t); @@ -297,35 +323,33 @@ pgm_print(netdissect_options *ndo, case PGM_POLR: { const struct pgm_polr *polr_msg; - polr_msg = (const struct pgm_polr *)(pgm + 1); + polr_msg = (const struct pgm_polr *)bp; ND_TCHECK_SIZE(polr_msg); ND_PRINT("POLR seq %u round %u", GET_BE_U_4(polr_msg->pgmp_seq), GET_BE_U_2(polr_msg->pgmp_round)); - bp = (const u_char *) (polr_msg + 1); + bp += sizeof(struct pgm_polr); break; } case PGM_ODATA: { const struct pgm_data *odata; - odata = (const struct pgm_data *)(pgm + 1); - ND_TCHECK_SIZE(odata); + odata = (const struct pgm_data *)bp; ND_PRINT("ODATA trail %u seq %u", GET_BE_U_4(odata->pgmd_trailseq), GET_BE_U_4(odata->pgmd_seq)); - bp = (const u_char *) (odata + 1); + bp += sizeof(struct pgm_data); break; } case PGM_RDATA: { const struct pgm_data *rdata; - rdata = (const struct pgm_data *)(pgm + 1); - ND_TCHECK_SIZE(rdata); + rdata = (const struct pgm_data *)bp; ND_PRINT("RDATA trail %u seq %u", GET_BE_U_4(rdata->pgmd_trailseq), GET_BE_U_4(rdata->pgmd_seq)); - bp = (const u_char *) (rdata + 1); + bp += sizeof(struct pgm_data); break; } @@ -335,28 +359,27 @@ pgm_print(netdissect_options *ndo, const struct pgm_nak *nak; char source_buf[INET6_ADDRSTRLEN], group_buf[INET6_ADDRSTRLEN]; - nak = (const struct pgm_nak *)(pgm + 1); + nak = (const struct pgm_nak *)bp; ND_TCHECK_SIZE(nak); - bp = (const u_char *) (nak + 1); + bp += sizeof(struct pgm_nak); /* * Skip past the source, saving info along the way * and stopping if we don't have enough. */ switch (GET_BE_U_2(nak->pgmn_source_afi)) { - case AFNUM_INET: + case AFNUM_IP: ND_TCHECK_LEN(bp, sizeof(nd_ipv4)); addrtostr(bp, source_buf, sizeof(source_buf)); bp += sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: ND_TCHECK_LEN(bp, sizeof(nd_ipv6)); addrtostr6(bp, source_buf, sizeof(source_buf)); bp += sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } /* @@ -364,21 +387,19 @@ pgm_print(netdissect_options *ndo, * and stopping if we don't have enough. */ bp += (2 * sizeof(uint16_t)); - ND_TCHECK_2(bp); switch (GET_BE_U_2(bp)) { - case AFNUM_INET: + case AFNUM_IP: ND_TCHECK_LEN(bp, sizeof(nd_ipv4)); addrtostr(bp, group_buf, sizeof(group_buf)); bp += sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: ND_TCHECK_LEN(bp, sizeof(nd_ipv6)); addrtostr6(bp, group_buf, sizeof(group_buf)); bp += sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } /* @@ -402,14 +423,15 @@ pgm_print(netdissect_options *ndo, break; } - case PGM_ACK: { + case PGM_ACK: + case PGM_ACK2: { const struct pgm_ack *ack; - ack = (const struct pgm_ack *)(pgm + 1); + ack = (const struct pgm_ack *)bp; ND_TCHECK_SIZE(ack); ND_PRINT("ACK seq %u", GET_BE_U_4(ack->pgma_rx_max_seq)); - bp = (const u_char *) (ack + 1); + bp += sizeof(struct pgm_ack); break; } @@ -459,7 +481,6 @@ pgm_print(netdissect_options *ndo, ND_PRINT("[Total option length leaves no room for final option]"); return; } - ND_TCHECK_2(bp); opt_type = GET_U_1(bp); bp++; opt_len = GET_U_1(bp); @@ -515,7 +536,6 @@ pgm_print(netdissect_options *ndo, ND_PRINT("[Option length not a multiple of 4]"); return; } - ND_TCHECK_4(bp); ND_PRINT(" %u", GET_BE_U_4(bp)); bp += 4; opt_len -= 4; @@ -580,7 +600,7 @@ pgm_print(netdissect_options *ndo, nla_afnum = GET_BE_U_2(bp); bp += 2+2; switch (nla_afnum) { - case AFNUM_INET: + case AFNUM_IP: if (opt_len != PGM_OPT_REDIRECT_FIXED_LEN + sizeof(nd_ipv4)) { ND_PRINT("[Bad OPT_REDIRECT option, length %u != %u + address size]", opt_len, PGM_OPT_REDIRECT_FIXED_LEN); @@ -591,10 +611,10 @@ pgm_print(netdissect_options *ndo, bp += sizeof(nd_ipv4); opts_len -= PGM_OPT_REDIRECT_FIXED_LEN + sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: if (opt_len != PGM_OPT_REDIRECT_FIXED_LEN + sizeof(nd_ipv6)) { ND_PRINT("[Bad OPT_REDIRECT option, length %u != %u + address size]", - PGM_OPT_REDIRECT_FIXED_LEN, opt_len); + opt_len, PGM_OPT_REDIRECT_FIXED_LEN); return; } ND_TCHECK_LEN(bp, sizeof(nd_ipv6)); @@ -603,8 +623,7 @@ pgm_print(netdissect_options *ndo, opts_len -= PGM_OPT_REDIRECT_FIXED_LEN + sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } ND_PRINT(" REDIRECT %s", nla_buf); @@ -666,7 +685,7 @@ pgm_print(netdissect_options *ndo, case PGM_OPT_PATH_NLA: ND_PRINT(" PATH_NLA [%u]", opt_len); - bp += opt_len; + bp += opt_len - 2; opts_len -= opt_len; break; @@ -708,7 +727,7 @@ pgm_print(netdissect_options *ndo, case PGM_OPT_CR: ND_PRINT(" CR"); - bp += opt_len; + bp += opt_len - 2; opts_len -= opt_len; break; @@ -737,7 +756,7 @@ pgm_print(netdissect_options *ndo, nla_afnum = GET_BE_U_2(bp); bp += 2+2; switch (nla_afnum) { - case AFNUM_INET: + case AFNUM_IP: if (opt_len != PGM_OPT_PGMCC_DATA_FIXED_LEN + sizeof(nd_ipv4)) { ND_PRINT("[Bad OPT_PGMCC_DATA option, length %u != %u + address size]", opt_len, PGM_OPT_PGMCC_DATA_FIXED_LEN); @@ -748,7 +767,7 @@ pgm_print(netdissect_options *ndo, bp += sizeof(nd_ipv4); opts_len -= PGM_OPT_PGMCC_DATA_FIXED_LEN + sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: if (opt_len != PGM_OPT_PGMCC_DATA_FIXED_LEN + sizeof(nd_ipv6)) { ND_PRINT("[Bad OPT_PGMCC_DATA option, length %u != %u + address size]", opt_len, PGM_OPT_PGMCC_DATA_FIXED_LEN); @@ -760,8 +779,7 @@ pgm_print(netdissect_options *ndo, opts_len -= PGM_OPT_PGMCC_DATA_FIXED_LEN + sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } ND_PRINT(" PGMCC DATA %u %s", offset, nla_buf); @@ -780,7 +798,7 @@ pgm_print(netdissect_options *ndo, nla_afnum = GET_BE_U_2(bp); bp += 2+2; switch (nla_afnum) { - case AFNUM_INET: + case AFNUM_IP: if (opt_len != PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN + sizeof(nd_ipv4)) { ND_PRINT("[Bad OPT_PGMCC_FEEDBACK option, length %u != %u + address size]", opt_len, PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN); @@ -791,7 +809,7 @@ pgm_print(netdissect_options *ndo, bp += sizeof(nd_ipv4); opts_len -= PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN + sizeof(nd_ipv4); break; - case AFNUM_INET6: + case AFNUM_IP6: if (opt_len != PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN + sizeof(nd_ipv6)) { ND_PRINT("[Bad OPT_PGMCC_FEEDBACK option, length %u != %u + address size]", opt_len, PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN); @@ -803,8 +821,7 @@ pgm_print(netdissect_options *ndo, opts_len -= PGM_OPT_PGMCC_FEEDBACK_FIXED_LEN + sizeof(nd_ipv6); break; default: - goto trunc; - break; + goto invalid; } ND_PRINT(" PGMCC FEEDBACK %u %s", offset, nla_buf); @@ -812,7 +829,7 @@ pgm_print(netdissect_options *ndo, default: ND_PRINT(" OPT_%02X [%u] ", opt_type, opt_len); - bp += opt_len; + bp += opt_len - 2; opts_len -= opt_len; break; } @@ -829,7 +846,6 @@ pgm_print(netdissect_options *ndo, GET_BE_U_2(pgm->pgm_length)); return; - -trunc: - nd_print_trunc(ndo); +invalid: + nd_print_invalid(ndo); }