X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/f085c93f59fb2332e09f3da20eef5fb2bbd04431..0023eaa78f123676bfa9c5fba72ea4b8a59aaa70:/print-msdp.c diff --git a/print-msdp.c b/print-msdp.c index 59a0a092..1d01233c 100644 --- a/print-msdp.c +++ b/print-msdp.c @@ -18,11 +18,10 @@ /* \summary: Multicast Source Discovery Protocol (MSDP) printer */ -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif +#include -#include +#define ND_LONGJMP_FROM_TCHECK +#include "netdissect-stdinc.h" #include "netdissect.h" #include "addrtoname.h" @@ -35,69 +34,93 @@ msdp_print(netdissect_options *ndo, const u_char *sp, u_int length) { unsigned int type, len; - ND_TCHECK_3(sp); + ndo->ndo_protocol = "msdp"; + ND_PRINT(": "); + nd_print_protocol(ndo); /* See if we think we're at the beginning of a compound packet */ - type = *sp; - len = EXTRACT_BE_U_2(sp + 1); + type = GET_U_1(sp); + len = GET_BE_U_2(sp + 1); if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX) goto trunc; /* not really truncated, but still not decodable */ - ND_PRINT((ndo, " msdp:")); - while (length > 0) { - ND_TCHECK_3(sp); - type = *sp; - len = EXTRACT_BE_U_2(sp + 1); + while (length != 0) { + unsigned int entry_count; + + if (length < 3) + goto trunc; + type = GET_U_1(sp); + len = GET_BE_U_2(sp + 1); if (len > 1400 || ndo->ndo_vflag) - ND_PRINT((ndo, " [len %u]", len)); + ND_PRINT(" [len %u]", len); if (len < 3) goto trunc; - sp += 3; - length -= 3; + if (length < len) + goto trunc; switch (type) { case 1: /* IPv4 Source-Active */ case 3: /* IPv4 Source-Active Response */ if (type == 1) - ND_PRINT((ndo, " SA")); + ND_PRINT(" SA"); else - ND_PRINT((ndo, " SA-Response")); - ND_TCHECK(*sp); - ND_PRINT((ndo, " %u entries", EXTRACT_U_1(sp))); - if ((u_int)((*sp * 12) + 8) < len) { - ND_PRINT((ndo, " [w/data]")); + ND_PRINT(" SA-Response"); + + /* Entry Count */ + if (len < 4) + goto trunc; + entry_count = GET_U_1(sp + 3); + ND_PRINT(" %u entries", entry_count); + + /* RP Address */ + if (len < 8) + goto trunc; + /* XXX -print this based on ndo_vflag? */ + ND_TCHECK_LEN(sp + 4, 4); + + /* Entries */ + ND_TCHECK_LEN(sp + 8, entry_count*12); + + if (len > (8 + entry_count*12)) { + /* Encapsulated IP packet */ + ND_PRINT(" [w/data]"); if (ndo->ndo_vflag > 1) { - ND_PRINT((ndo, " ")); - ip_print(ndo, sp + *sp * 12 + 8 - 3, - len - (*sp * 12 + 8)); + ND_PRINT(" "); + ip_print(ndo, sp + (8 + entry_count*12), + len - (8 + entry_count*12)); } } break; case 2: - ND_PRINT((ndo, " SA-Request")); - ND_TCHECK_5(sp); - ND_PRINT((ndo, " for %s", ipaddr_string(ndo, sp + 1))); + /* draft-ietf-msdp-spec-13 */ + ND_PRINT(" SA-Request"); + + /* Reserved */ + if (len < 4) + goto trunc; + ND_TCHECK_1(sp + 3); + + /* Group Address */ + if (len < 8) + goto trunc; + if (len != 8) + ND_PRINT("[len=%u] ", len); + ND_PRINT(" for %s", GET_IPADDR_STRING(sp + 4)); break; case 4: - ND_PRINT((ndo, " Keepalive")); + ND_PRINT(" Keepalive"); if (len != 3) - ND_PRINT((ndo, "[len=%d] ", len)); + ND_PRINT("[len=%u] ", len); break; case 5: - ND_PRINT((ndo, " Notification")); + ND_PRINT(" Notification"); break; default: - ND_PRINT((ndo, " [type=%d len=%d]", type, len)); + ND_PRINT(" [type=%u len=%u]", type, len); break; } - sp += (len - 3); - length -= (len - 3); + ND_TCHECK_LEN(sp, len); + sp += len; + length -= len; } return; trunc: - ND_PRINT((ndo, " [|msdp]")); + nd_print_trunc(ndo); } - -/* - * Local Variables: - * c-style: whitesmith - * c-basic-offset: 8 - * End: - */