X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/db2c996e9cf5abfb6e5d91350c380a35815df3c8..5ef0bcb5edd748de9d9af13c40da0395dfdd94e8:/print-domain.c diff --git a/print-domain.c b/print-domain.c index 63c541a8..ad08073f 100644 --- a/print-domain.c +++ b/print-domain.c @@ -116,25 +116,19 @@ blabel_print(netdissect_options *ndo, /* print the bit string as a hex string */ ND_PRINT("\\[x"); for (bitp = cp + 1, b = bitlen; bitp < lim && b > 7; b -= 8, bitp++) { - ND_TCHECK_1(bitp); ND_PRINT("%02x", GET_U_1(bitp)); } if (b > 4) { - ND_TCHECK_1(bitp); tc = GET_U_1(bitp); bitp++; ND_PRINT("%02x", tc & (0xff << (8 - b))); } else if (b > 0) { - ND_TCHECK_1(bitp); tc = GET_U_1(bitp); bitp++; ND_PRINT("%1x", ((tc >> 4) & 0x0f) & (0x0f << (4 - b))); } ND_PRINT("/%u]", bitlen); return lim; -trunc: - ND_PRINT(".../%u]", bitlen); - return NULL; } static int @@ -267,9 +261,176 @@ ns_cprint(netdissect_options *ndo, return (cp + i); } +static void +print_eopt_ecs(netdissect_options *ndo, const u_char *cp, + u_int data_len) +{ + u_int family, addr_bits, src_len, scope_len; + + u_char padded[32]; + char addr[INET6_ADDRSTRLEN]; + + /* ecs option must at least contain family, src len, and scope len */ + if (data_len < 4) { + nd_print_invalid(ndo); + return; + } + + family = GET_BE_U_2(cp); + cp += 2; + src_len = GET_U_1(cp); + cp += 1; + scope_len = GET_U_1(cp); + cp += 1; + + if (family == 1) + addr_bits = 32; + else if (family == 2) + addr_bits = 128; + else { + nd_print_invalid(ndo); + return; + } + + if (data_len - 4 > (addr_bits / 8)) { + nd_print_invalid(ndo); + return; + } + /* checks for invalid ecs scope or source length */ + if (src_len > addr_bits || scope_len > addr_bits || ((src_len + 7) / 8) != (data_len - 4)) { + nd_print_invalid(ndo); + return; + } + + /* pad the truncated address from ecs with zeros */ + memset(padded, 0, sizeof(padded)); + memcpy(padded, cp, data_len - 4); + + + if (family == 1) + ND_PRINT("%s/%d/%d", addrtostr(padded, addr, INET_ADDRSTRLEN), + src_len, scope_len); + else + ND_PRINT("%s/%d/%d", addrtostr6(padded, addr, INET6_ADDRSTRLEN), + src_len, scope_len); + +} + +extern const struct tok edns_opt2str[]; +extern const struct tok dau_alg2str[]; +extern const struct tok dhu_alg2str[]; +extern const struct tok n3u_alg2str[]; + + +/* print an */ +static const u_char * +eopt_print(netdissect_options *ndo, + const u_char *cp) +{ + u_int opt, data_len, i; + + if (!ND_TTEST_2(cp)) + return (NULL); + opt = GET_BE_U_2(cp); + cp += 2; + ND_PRINT("%s", tok2str(edns_opt2str, "Opt%u", opt)); + if (!ND_TTEST_2(cp)) + return (NULL); + data_len = GET_BE_U_2(cp); + cp += 2; + + ND_TCHECK_LEN(cp, data_len); + + if (data_len > 0) { + ND_PRINT(" "); + switch (opt) { + + case E_ECS: + print_eopt_ecs(ndo, cp, data_len); + break; + case E_COOKIE: + if (data_len < 8 || (data_len > 8 && data_len < 16) || data_len > 40) + nd_print_invalid(ndo); + else { + for (i = 0; i < data_len; ++i) { + /* split client and server cookie */ + if (i == 8) + ND_PRINT(" "); + ND_PRINT("%02x", GET_U_1(cp + i)); + } + } + break; + case E_KEEPALIVE: + if (data_len != 2) + nd_print_invalid(ndo); + else + /* keepalive is in increments of 100ms. Convert to seconds */ + ND_PRINT("%0.1f sec", (GET_BE_U_2(cp) / 10.0)); + break; + case E_EXPIRE: + if (data_len != 4) + nd_print_invalid(ndo); + else + ND_PRINT("%u sec", GET_BE_U_4(cp)); + break; + case E_PADDING: + /* ignore contents and just print length */ + ND_PRINT("(%u)", data_len); + break; + case E_KEYTAG: + if (data_len % 2 != 0) + nd_print_invalid(ndo); + else + for (i = 0; i < data_len; i += 2) { + if (i > 0) + ND_PRINT(" "); + ND_PRINT("%u", GET_BE_U_2(cp + i)); + } + break; + case E_DAU: + for (i = 0; i < data_len; ++i) { + if (i > 0) + ND_PRINT(" "); + ND_PRINT("%s", tok2str(dau_alg2str, "Alg_%u", GET_U_1(cp + i))); + } + break; + case E_DHU: + for (i = 0; i < data_len; ++i) { + if (i > 0) + ND_PRINT(" "); + ND_PRINT("%s", tok2str(dhu_alg2str, "Alg_%u", GET_U_1(cp + i))); + } + break; + case E_N3U: + for (i = 0; i < data_len; ++i) { + if (i > 0) + ND_PRINT(" "); + ND_PRINT("%s", tok2str(n3u_alg2str, "Alg_%u", GET_U_1(cp + i))); + } + break; + case E_CHAIN: + fqdn_print(ndo, cp, cp + data_len); + break; + case E_NSID: + /* intentional fall-through. NSID is an undefined byte string */ + default: + for (i = 0; i < data_len; ++i) + ND_PRINT("%02x", GET_U_1(cp + i)); + break; + } + } + return (cp + data_len); + + trunc: + return (NULL); + +} + + + extern const struct tok ns_type2str[]; -/* http://www.iana.org/assignments/dns-parameters */ +/* https://www.iana.org/assignments/dns-parameters */ const struct tok ns_type2str[] = { { T_A, "A" }, /* RFC 1035 */ { T_NS, "NS" }, /* RFC 1035 */ @@ -332,6 +493,7 @@ const struct tok ns_type2str[] = { { T_MAILB, "MAILB" }, /* RFC 1035 */ { T_MAILA, "MAILA" }, /* RFC 1035 */ { T_ANY, "ANY" }, + { T_URI, "URI" }, /* RFC 7553 */ { 0, NULL } }; @@ -345,6 +507,59 @@ const struct tok ns_class2str[] = { { 0, NULL } }; +const struct tok edns_opt2str[] = { + { E_LLQ, "LLQ" }, + { E_UL, "UL" }, + { E_NSID, "NSID" }, + { E_DAU, "DAU" }, + { E_DHU, "DHU" }, + { E_N3U, "N3U" }, + { E_ECS, "ECS" }, + { E_EXPIRE, "EXPIRE" }, + { E_COOKIE, "COOKIE" }, + { E_KEEPALIVE, "KEEPALIVE" }, + { E_PADDING, "PADDING" }, + { E_CHAIN, "CHAIN" }, + { E_KEYTAG, "KEY-TAG" }, + { E_CLIENTTAG, "CLIENT-TAG" }, + { E_SERVERTAG, "SERVER-TAG" }, + { 0, NULL } +}; + +const struct tok dau_alg2str[] = { + { A_DELETE, "DELETE" }, + { A_RSAMD5, "RSAMD5" }, + { A_DH, "DH" }, + { A_DSA, "DS" }, + { A_RSASHA1, "RSASHA1" }, + { A_DSA_NSEC3_SHA1, "DSA-NSEC3-SHA1" }, + { A_RSASHA1_NSEC3_SHA1, "RSASHA1-NSEC3-SHA1" }, + { A_RSASHA256, "RSASHA256" }, + { A_RSASHA512, "RSASHA512" }, + { A_ECC_GOST, "ECC-GOST" }, + { A_ECDSAP256SHA256, "ECDSAP256SHA256" }, + { A_ECDSAP384SHA384, "ECDSAP384SHA384" }, + { A_ED25519, "ED25519" }, + { A_ED448, "ED448" }, + { A_INDIRECT, "INDIRECT" }, + { A_PRIVATEDNS, "PRIVATEDNS" }, + { A_PRIVATEOID, "PRIVATEOID" }, + { 0, NULL } +}; + +const struct tok dhu_alg2str[] = { + { DS_SHA1, "SHA-1" }, + { DS_SHA256,"SHA-256" }, + { DS_GOST, "GOST_R_34.11-94" }, + { DS_SHA384,"SHA-384" }, + { 0, NULL } +}; + +const struct tok n3u_alg2str[] = { + { NSEC_SHA1,"SHA-1" }, + { 0, NULL } +}; + /* print a query */ static const u_char * ns_qprint(netdissect_options *ndo, @@ -525,7 +740,7 @@ ns_rprint(netdissect_options *ndo, case T_A6: { - struct in6_addr a; + nd_ipv6 a; int pbit, pbyte; char ntop_buf[INET6_ADDRSTRLEN]; @@ -539,8 +754,8 @@ ns_rprint(netdissect_options *ndo, } else if (pbit < 128) { if (!ND_TTEST_LEN(cp + 1, sizeof(a) - pbyte)) return(NULL); - memset(&a, 0, sizeof(a)); - memcpy(&a.s6_addr[pbyte], cp + 1, sizeof(a) - pbyte); + memset(a, 0, sizeof(a)); + memcpy(a + pbyte, cp + 1, sizeof(a) - pbyte); ND_PRINT(" %u %s", pbit, addrtostr6(&a, ntop_buf, sizeof(ntop_buf))); } @@ -552,10 +767,29 @@ ns_rprint(netdissect_options *ndo, break; } + case T_URI: + if (!ND_TTEST_LEN(cp, len)) + return(NULL); + ND_PRINT(" %u %u ", GET_BE_U_2(cp), GET_BE_U_2(cp + 2)); + if (nd_printn(ndo, cp + 4, len - 4, ndo->ndo_snapend)) + return(NULL); + break; + case T_OPT: ND_PRINT(" UDPsize=%u", class); if (opt_flags & 0x8000) ND_PRINT(" DO"); + if (cp < rp) { + ND_PRINT(" ["); + while (cp < rp) { + cp = eopt_print(ndo, cp); + if (cp == NULL) + return(NULL); + if (cp < rp) + ND_PRINT(","); + } + ND_PRINT("]"); + } break; case T_UNSPECA: /* One long string */ @@ -602,7 +836,7 @@ ns_rprint(netdissect_options *ndo, void domain_print(netdissect_options *ndo, - const u_char *bp, u_int length, int is_mdns) + const u_char *bp, u_int length, int over_tcp, int is_mdns) { const dns_header_t *np; uint16_t flags, rcode, rdlen, type; @@ -612,7 +846,43 @@ domain_print(netdissect_options *ndo, uint16_t b2; ndo->ndo_protocol = "domain"; + + if (over_tcp) { + /* + * The message is prefixed with a two byte length field + * which gives the message length, excluding the two byte + * length field. (RFC 1035 - 4.2.2. TCP usage) + */ + if (length < 2) { + ND_PRINT(" [DNS over TCP: length %u < 2]", length); + nd_print_invalid(ndo); + return; + } else { + length -= 2; /* excluding the two byte length field */ + if (GET_BE_U_2(bp) != length) { + ND_PRINT(" [prefix length(%u) != length(%u)]", + GET_BE_U_2(bp), length); + nd_print_invalid(ndo); + return; + } else { + bp += 2; + /* in over TCP case, we need to prepend a space + * (not needed in over UDP case) + */ + ND_PRINT(" "); + } + } + } + np = (const dns_header_t *)bp; + + if(length < sizeof(*np)) { + nd_print_protocol(ndo); + ND_PRINT(" [length %u < %zu]", length, sizeof(*np)); + nd_print_invalid(ndo); + return; + } + ND_TCHECK_SIZE(np); flags = GET_BE_U_2(np->flags); /* get the byte-order right */ @@ -652,7 +922,7 @@ domain_print(netdissect_options *ndo, if (cp + 1 > ndo->ndo_snapend) goto print; if (type == T_OPT) { - rcode |= (*cp << 4); + rcode |= (GET_U_1(cp) << 4); goto print; } cp += 4;