diff options
Diffstat (limited to 'print-domain.c')
-rw-r--r-- | print-domain.c | 1171 |
1 files changed, 1171 insertions, 0 deletions
diff --git a/print-domain.c b/print-domain.c new file mode 100644 index 0000000..d2275a5 --- /dev/null +++ b/print-domain.c @@ -0,0 +1,1171 @@ +/* + * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 + * The Regents of the University of California. All rights reserved. + * + * 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, (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, and (3) all advertising materials mentioning + * features or use of this software display the following acknowledgement: + * ``This product includes software developed by the University of California, + * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of + * the University nor the names of its contributors may be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * 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. + */ + +/* \summary: Domain Name System (DNS) printer */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "netdissect-stdinc.h" + +#include <string.h> + +#include "netdissect.h" +#include "addrtoname.h" +#include "addrtostr.h" +#include "extract.h" + +#include "nameser.h" + +static const char *ns_ops[] = { + "", " inv_q", " stat", " op3", " notify", " update", " op6", " op7", + " op8", " updateA", " updateD", " updateDA", + " updateM", " updateMA", " zoneInit", " zoneRef", +}; + +static const char *ns_resp[] = { + "", " FormErr", " ServFail", " NXDomain", + " NotImp", " Refused", " YXDomain", " YXRRSet", + " NXRRSet", " NotAuth", " NotZone", " Resp11", + " Resp12", " Resp13", " Resp14", " NoChange", + " BadVers", "Resp17", " Resp18", " Resp19", + " Resp20", "Resp21", " Resp22", " BadCookie", +}; + +static const char * +ns_rcode(u_int rcode) { + static char buf[sizeof(" Resp4095")]; + + if (rcode < sizeof(ns_resp)/sizeof(ns_resp[0])) { + return (ns_resp[rcode]); + } + snprintf(buf, sizeof(buf), " Resp%u", rcode & 0xfff); + return (buf); +} + +/* skip over a domain name */ +static const u_char * +ns_nskip(netdissect_options *ndo, + const u_char *cp) +{ + u_char i; + + if (!ND_TTEST_1(cp)) + return (NULL); + i = GET_U_1(cp); + cp++; + while (i) { + switch (i & TYPE_MASK) { + + case TYPE_INDIR: + return (cp + 1); + + case TYPE_EDNS0: { + int bitlen, bytelen; + + if ((i & ~TYPE_MASK) != EDNS0_ELT_BITLABEL) + return(NULL); /* unknown ELT */ + if (!ND_TTEST_1(cp)) + return (NULL); + if ((bitlen = GET_U_1(cp)) == 0) + bitlen = 256; + cp++; + bytelen = (bitlen + 7) / 8; + cp += bytelen; + } + break; + + case TYPE_RESERVED: + return (NULL); + + case TYPE_LABEL: + cp += i; + break; + } + if (!ND_TTEST_1(cp)) + return (NULL); + i = GET_U_1(cp); + cp++; + } + return (cp); +} + +static const u_char * +blabel_print(netdissect_options *ndo, + const u_char *cp) +{ + u_int bitlen, slen, b; + const u_char *bitp, *lim; + uint8_t tc; + + if (!ND_TTEST_1(cp)) + return(NULL); + if ((bitlen = GET_U_1(cp)) == 0) + bitlen = 256; + slen = (bitlen + 3) / 4; + lim = cp + 1 + slen; + + /* 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_PRINT("%02x", GET_U_1(bitp)); + } + if (b > 4) { + tc = GET_U_1(bitp); + bitp++; + ND_PRINT("%02x", tc & (0xff << (8 - b))); + } else if (b > 0) { + tc = GET_U_1(bitp); + bitp++; + ND_PRINT("%1x", ((tc >> 4) & 0x0f) & (0x0f << (4 - b))); + } + ND_PRINT("/%u]", bitlen); + return lim; +} + +static int +labellen(netdissect_options *ndo, + const u_char *cp) +{ + u_int i; + + if (!ND_TTEST_1(cp)) + return(-1); + i = GET_U_1(cp); + switch (i & TYPE_MASK) { + + case TYPE_EDNS0: { + u_int bitlen, elt; + if ((elt = (i & ~TYPE_MASK)) != EDNS0_ELT_BITLABEL) { + ND_PRINT("<ELT %d>", elt); + return(-1); + } + if (!ND_TTEST_1(cp + 1)) + return(-1); + if ((bitlen = GET_U_1(cp + 1)) == 0) + bitlen = 256; + return(((bitlen + 7) / 8) + 1); + } + + case TYPE_INDIR: + case TYPE_LABEL: + return(i); + + default: + /* + * TYPE_RESERVED, but we use default to suppress compiler + * warnings about falling out of the switch statement. + */ + ND_PRINT("<BAD LABEL TYPE>"); + return(-1); + } +} + +/* print a <domain-name> */ +const u_char * +fqdn_print(netdissect_options *ndo, + const u_char *cp, const u_char *bp) +{ + u_int i, l; + const u_char *rp = NULL; + int compress = 0; + u_int elt; + u_int offset, max_offset; + u_int name_chars = 0; + + if ((l = labellen(ndo, cp)) == (u_int)-1) + return(NULL); + if (!ND_TTEST_1(cp)) + return(NULL); + max_offset = (u_int)(cp - bp); + i = GET_U_1(cp); + cp++; + if ((i & TYPE_MASK) != TYPE_INDIR) { + compress = 0; + rp = cp + l; + } + + if (i != 0) { + while (i && cp < ndo->ndo_snapend) { + switch (i & TYPE_MASK) { + + case TYPE_INDIR: + if (!compress) { + rp = cp + 1; + compress = 1; + } + if (!ND_TTEST_1(cp)) + return(NULL); + offset = (((i << 8) | GET_U_1(cp)) & 0x3fff); + /* + * This must move backwards in the packet. + * No RFC explicitly says that, but BIND's + * name decompression code requires it, + * as a way of preventing infinite loops + * and other bad behavior, and it's probably + * what was intended (compress by pointing + * to domain name suffixes already seen in + * the packet). + */ + if (offset >= max_offset) { + ND_PRINT("<BAD PTR>"); + return(NULL); + } + max_offset = offset; + cp = bp + offset; + if (!ND_TTEST_1(cp)) + return(NULL); + i = GET_U_1(cp); + if ((l = labellen(ndo, cp)) == (u_int)-1) + return(NULL); + cp++; + continue; + + case TYPE_EDNS0: + elt = (i & ~TYPE_MASK); + switch(elt) { + case EDNS0_ELT_BITLABEL: + if (blabel_print(ndo, cp) == NULL) + return (NULL); + break; + default: + /* unknown ELT */ + ND_PRINT("<ELT %u>", elt); + return(NULL); + } + break; + + case TYPE_RESERVED: + ND_PRINT("<BAD LABEL TYPE>"); + return(NULL); + + case TYPE_LABEL: + if (name_chars + l <= MAXCDNAME) { + if (nd_printn(ndo, cp, l, ndo->ndo_snapend)) + return(NULL); + } else if (name_chars < MAXCDNAME) { + if (nd_printn(ndo, cp, + MAXCDNAME - name_chars, ndo->ndo_snapend)) + return(NULL); + } + name_chars += l; + break; + } + + cp += l; + if (name_chars <= MAXCDNAME) + ND_PRINT("."); + name_chars++; + if (!ND_TTEST_1(cp)) + return(NULL); + i = GET_U_1(cp); + if ((l = labellen(ndo, cp)) == (u_int)-1) + return(NULL); + cp++; + if (!compress) + rp += l + 1; + } + if (name_chars > MAXCDNAME) + ND_PRINT("<DOMAIN NAME TOO LONG>"); + } else + ND_PRINT("."); + return (rp); +} + +/* print a <character-string> */ +static const u_char * +ns_cprint(netdissect_options *ndo, + const u_char *cp) +{ + u_int i; + + if (!ND_TTEST_1(cp)) + return (NULL); + i = GET_U_1(cp); + cp++; + if (nd_printn(ndo, cp, i, ndo->ndo_snapend)) + return (NULL); + 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 <EDNS-option> */ +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[]; + +/* https://www.iana.org/assignments/dns-parameters */ +const struct tok ns_type2str[] = { + { T_A, "A" }, /* RFC 1035 */ + { T_NS, "NS" }, /* RFC 1035 */ + { T_MD, "MD" }, /* RFC 1035 */ + { T_MF, "MF" }, /* RFC 1035 */ + { T_CNAME, "CNAME" }, /* RFC 1035 */ + { T_SOA, "SOA" }, /* RFC 1035 */ + { T_MB, "MB" }, /* RFC 1035 */ + { T_MG, "MG" }, /* RFC 1035 */ + { T_MR, "MR" }, /* RFC 1035 */ + { T_NULL, "NULL" }, /* RFC 1035 */ + { T_WKS, "WKS" }, /* RFC 1035 */ + { T_PTR, "PTR" }, /* RFC 1035 */ + { T_HINFO, "HINFO" }, /* RFC 1035 */ + { T_MINFO, "MINFO" }, /* RFC 1035 */ + { T_MX, "MX" }, /* RFC 1035 */ + { T_TXT, "TXT" }, /* RFC 1035 */ + { T_RP, "RP" }, /* RFC 1183 */ + { T_AFSDB, "AFSDB" }, /* RFC 5864 */ + { T_X25, "X25" }, /* RFC 1183 */ + { T_ISDN, "ISDN" }, /* RFC 1183 */ + { T_RT, "RT" }, /* RFC 1183 */ + { T_NSAP, "NSAP" }, /* RFC 1706 */ + { T_NSAP_PTR, "NSAP_PTR" }, /* RFC 1706 */ + { T_SIG, "SIG" }, /* RFC 3008 */ + { T_KEY, "KEY" }, /* RFC 3110 */ + { T_PX, "PX" }, /* RFC 2163 */ + { T_GPOS, "GPOS" }, /* RFC 1712 */ + { T_AAAA, "AAAA" }, /* RFC 3596 */ + { T_LOC, "LOC" }, /* RFC 1876 */ + { T_NXT, "NXT" }, /* RFC 3755 */ + { T_EID, "EID" }, /* Nimrod */ + { T_NIMLOC, "NIMLOC" }, /* Nimrod */ + { T_SRV, "SRV" }, /* RFC 2782 */ + { T_ATMA, "ATMA" }, /* ATM Forum */ + { T_NAPTR, "NAPTR" }, /* RFC 3403 */ + { T_KX, "KX" }, /* RFC 2230 */ + { T_CERT, "CERT" }, /* RFC 4398 */ + { T_A6, "A6" }, /* RFC 6563 */ + { T_DNAME, "DNAME" }, /* RFC 6672 */ + { T_SINK, "SINK" }, + { T_OPT, "OPT" }, /* RFC 6891 */ + { T_APL, "APL" }, /* RFC 3123 */ + { T_DS, "DS" }, /* RFC 4034 */ + { T_SSHFP, "SSHFP" }, /* RFC 4255 */ + { T_IPSECKEY, "IPSECKEY" }, /* RFC 4025 */ + { T_RRSIG, "RRSIG" }, /* RFC 4034 */ + { T_NSEC, "NSEC" }, /* RFC 4034 */ + { T_DNSKEY, "DNSKEY" }, /* RFC 4034 */ + { T_DHCID, "DHCID" }, /* RFC 4071 */ + { T_NSEC3, "NSEC3" }, /* RFC 5155 */ + { T_NSEC3PARAM, "NSEC3PARAM" }, /* RFC 5155 */ + { T_TLSA, "TLSA" }, /* RFC 6698 */ + { T_SMIMEA, "SMIMEA" }, /* RFC 8162 */ + { T_HIP, "HIP" }, /* RFC 8005 */ + { T_NINFO, "NINFO" }, + { T_RKEY, "RKEY" }, + { T_TALINK, "TALINK" }, + { T_CDS, "CDS" }, /* RFC 7344 */ + { T_CDNSKEY, "CDNSKEY" }, /* RFC 7344 */ + { T_OPENPGPKEY, "OPENPGPKEY" }, /* RFC 7929 */ + { T_CSYNC, "CSYNC" }, /* RFC 7477 */ + { T_ZONEMD, "ZONEMD" }, /* RFC 8976 */ + { T_SVCB, "SVCB" }, + { T_HTTPS, "HTTPS" }, + { T_SPF, "SPF" }, /* RFC 7208 */ + { T_UINFO, "UINFO" }, + { T_UID, "UID" }, + { T_GID, "GID" }, + { T_UNSPEC, "UNSPEC" }, + { T_NID, "NID" }, /* RFC 6742 */ + { T_L32, "L32" }, /* RFC 6742 */ + { T_L64, "L64" }, /* RFC 6742 */ + { T_LP, "LP" }, /* RFC 6742 */ + { T_EUI48, "EUI48" }, /* RFC 7043 */ + { T_EUI64, "EUI64" }, /* RFC 7043 */ + { T_TKEY, "TKEY" }, /* RFC 2930 */ + { T_TSIG, "TSIG" }, /* RFC 8945 */ + { T_IXFR, "IXFR" }, /* RFC 1995 */ + { T_AXFR, "AXFR" }, /* RFC 5936 */ + { T_MAILB, "MAILB" }, /* RFC 1035 */ + { T_MAILA, "MAILA" }, /* RFC 1035 */ + { T_ANY, "ANY" }, /* RFC 8482 */ + { T_URI, "URI" }, /* RFC 7553 */ + { T_CAA, "CAA" }, /* RFC 8659 */ + { T_AVC, "AVC" }, + { T_DOA, "DOA" }, + { T_AMTRELAY, "AMTRELAY" }, /* RFC 8777 */ + { T_TA, "TA" }, + { T_DLV, "DLV" }, /* RFC 8749 */ + { 0, NULL } +}; + +extern const struct tok ns_class2str[]; + +const struct tok ns_class2str[] = { + { C_IN, "IN" }, /* Not used */ + { C_CHAOS, "CHAOS" }, + { C_HS, "HS" }, + { C_ANY, "ANY" }, + { 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, + const u_char *cp, const u_char *bp, int is_mdns) +{ + const u_char *np = cp; + u_int i, class; + + cp = ns_nskip(ndo, cp); + + if (cp == NULL || !ND_TTEST_4(cp)) + return(NULL); + + /* print the qtype */ + i = GET_BE_U_2(cp); + cp += 2; + ND_PRINT(" %s", tok2str(ns_type2str, "Type%u", i)); + /* print the qclass (if it's not IN) */ + i = GET_BE_U_2(cp); + cp += 2; + if (is_mdns) + class = (i & ~C_QU); + else + class = i; + if (class != C_IN) + ND_PRINT(" %s", tok2str(ns_class2str, "(Class %u)", class)); + if (is_mdns) { + ND_PRINT(i & C_QU ? " (QU)" : " (QM)"); + } + + ND_PRINT("? "); + cp = fqdn_print(ndo, np, bp); + return(cp ? cp + 4 : NULL); +} + +/* print a reply */ +static const u_char * +ns_rprint(netdissect_options *ndo, + const u_char *cp, const u_char *bp, int is_mdns) +{ + u_int i, class, opt_flags = 0; + u_short typ, len; + const u_char *rp; + + if (ndo->ndo_vflag) { + ND_PRINT(" "); + if ((cp = fqdn_print(ndo, cp, bp)) == NULL) + return NULL; + } else + cp = ns_nskip(ndo, cp); + + if (cp == NULL || !ND_TTEST_LEN(cp, 10)) + return (ndo->ndo_snapend); + + /* print the type/qtype */ + typ = GET_BE_U_2(cp); + cp += 2; + /* print the class (if it's not IN and the type isn't OPT) */ + i = GET_BE_U_2(cp); + cp += 2; + if (is_mdns) + class = (i & ~C_CACHE_FLUSH); + else + class = i; + if (class != C_IN && typ != T_OPT) + ND_PRINT(" %s", tok2str(ns_class2str, "(Class %u)", class)); + if (is_mdns) { + if (i & C_CACHE_FLUSH) + ND_PRINT(" (Cache flush)"); + } + + if (typ == T_OPT) { + /* get opt flags */ + cp += 2; + opt_flags = GET_BE_U_2(cp); + /* ignore rest of ttl field */ + cp += 2; + } else if (ndo->ndo_vflag > 2) { + /* print ttl */ + ND_PRINT(" ["); + unsigned_relts_print(ndo, GET_BE_U_4(cp)); + ND_PRINT("]"); + cp += 4; + } else { + /* ignore ttl */ + cp += 4; + } + + len = GET_BE_U_2(cp); + cp += 2; + + rp = cp + len; + + ND_PRINT(" %s", tok2str(ns_type2str, "Type%u", typ)); + if (rp > ndo->ndo_snapend) + return(NULL); + + switch (typ) { + case T_A: + if (!ND_TTEST_LEN(cp, sizeof(nd_ipv4))) + return(NULL); + ND_PRINT(" %s", intoa(GET_IPV4_TO_NETWORK_ORDER(cp))); + break; + + case T_NS: + case T_CNAME: + case T_PTR: + case T_DNAME: + ND_PRINT(" "); + if (fqdn_print(ndo, cp, bp) == NULL) + return(NULL); + break; + + case T_SOA: + if (!ndo->ndo_vflag) + break; + ND_PRINT(" "); + if ((cp = fqdn_print(ndo, cp, bp)) == NULL) + return(NULL); + ND_PRINT(" "); + if ((cp = fqdn_print(ndo, cp, bp)) == NULL) + return(NULL); + if (!ND_TTEST_LEN(cp, 5 * 4)) + return(NULL); + ND_PRINT(" %u", GET_BE_U_4(cp)); + cp += 4; + ND_PRINT(" %u", GET_BE_U_4(cp)); + cp += 4; + ND_PRINT(" %u", GET_BE_U_4(cp)); + cp += 4; + ND_PRINT(" %u", GET_BE_U_4(cp)); + cp += 4; + ND_PRINT(" %u", GET_BE_U_4(cp)); + cp += 4; + break; + case T_MX: + ND_PRINT(" "); + if (!ND_TTEST_2(cp)) + return(NULL); + if (fqdn_print(ndo, cp + 2, bp) == NULL) + return(NULL); + ND_PRINT(" %u", GET_BE_U_2(cp)); + break; + + case T_TXT: + while (cp < rp) { + ND_PRINT(" \""); + cp = ns_cprint(ndo, cp); + if (cp == NULL) + return(NULL); + ND_PRINT("\""); + } + break; + + case T_SRV: + ND_PRINT(" "); + if (!ND_TTEST_6(cp)) + return(NULL); + if (fqdn_print(ndo, cp + 6, bp) == NULL) + return(NULL); + ND_PRINT(":%u %u %u", GET_BE_U_2(cp + 4), + GET_BE_U_2(cp), GET_BE_U_2(cp + 2)); + break; + + case T_AAAA: + { + char ntop_buf[INET6_ADDRSTRLEN]; + + if (!ND_TTEST_LEN(cp, sizeof(nd_ipv6))) + return(NULL); + ND_PRINT(" %s", + addrtostr6(cp, ntop_buf, sizeof(ntop_buf))); + + break; + } + + case T_A6: + { + nd_ipv6 a; + int pbit, pbyte; + char ntop_buf[INET6_ADDRSTRLEN]; + + if (!ND_TTEST_1(cp)) + return(NULL); + pbit = GET_U_1(cp); + pbyte = (pbit & ~7) / 8; + if (pbit > 128) { + ND_PRINT(" %u(bad plen)", pbit); + break; + } else if (pbit < 128) { + memset(a, 0, sizeof(a)); + GET_CPY_BYTES(a + pbyte, cp + 1, sizeof(a) - pbyte); + ND_PRINT(" %u %s", pbit, + addrtostr6(&a, ntop_buf, sizeof(ntop_buf))); + } + if (pbit > 0) { + ND_PRINT(" "); + if (fqdn_print(ndo, cp + 1 + sizeof(a) - pbyte, bp) == NULL) + return(NULL); + } + 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_TSIG: + { + if (cp + len > ndo->ndo_snapend) + return(NULL); + if (!ndo->ndo_vflag) + break; + ND_PRINT(" "); + if ((cp = fqdn_print(ndo, cp, bp)) == NULL) + return(NULL); + cp += 6; + if (!ND_TTEST_2(cp)) + return(NULL); + ND_PRINT(" fudge=%u", GET_BE_U_2(cp)); + cp += 2; + if (!ND_TTEST_2(cp)) + return(NULL); + ND_PRINT(" maclen=%u", GET_BE_U_2(cp)); + cp += 2 + GET_BE_U_2(cp); + if (!ND_TTEST_2(cp)) + return(NULL); + ND_PRINT(" origid=%u", GET_BE_U_2(cp)); + cp += 2; + if (!ND_TTEST_2(cp)) + return(NULL); + ND_PRINT(" error=%u", GET_BE_U_2(cp)); + cp += 2; + if (!ND_TTEST_2(cp)) + return(NULL); + ND_PRINT(" otherlen=%u", GET_BE_U_2(cp)); + cp += 2; + } + } + return (rp); /* XXX This isn't always right */ +} + +void +domain_print(netdissect_options *ndo, + const u_char *bp, u_int length, int over_tcp, int is_mdns) +{ + const dns_header_t *np; + uint16_t flags, rcode, rdlen, type; + u_int qdcount, ancount, nscount, arcount; + u_int i; + const u_char *cp; + 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 */ + qdcount = GET_BE_U_2(np->qdcount); + ancount = GET_BE_U_2(np->ancount); + nscount = GET_BE_U_2(np->nscount); + arcount = GET_BE_U_2(np->arcount); + + /* find the opt record to extract extended rcode */ + cp = (const u_char *)(np + 1); + rcode = DNS_RCODE(flags); + for (i = 0; i < qdcount; i++) { + if ((cp = ns_nskip(ndo, cp)) == NULL) + goto print; + cp += 4; /* skip QTYPE and QCLASS */ + if (cp >= ndo->ndo_snapend) + goto print; + } + for (i = 0; i < ancount + nscount; i++) { + if ((cp = ns_nskip(ndo, cp)) == NULL) + goto print; + cp += 8; /* skip TYPE, CLASS and TTL */ + if (cp + 2 > ndo->ndo_snapend) + goto print; + rdlen = GET_BE_U_2(cp); + cp += 2 + rdlen; + if (cp >= ndo->ndo_snapend) + goto print; + } + for (i = 0; i < arcount; i++) { + if ((cp = ns_nskip(ndo, cp)) == NULL) + goto print; + if (cp + 2 > ndo->ndo_snapend) + goto print; + type = GET_BE_U_2(cp); + cp += 4; /* skip TYPE and CLASS */ + if (cp + 1 > ndo->ndo_snapend) + goto print; + if (type == T_OPT) { + rcode |= (GET_U_1(cp) << 4); + goto print; + } + cp += 4; + if (cp + 2 > ndo->ndo_snapend) + goto print; + rdlen = GET_BE_U_2(cp); + cp += 2 + rdlen; + if (cp >= ndo->ndo_snapend) + goto print; + } + + print: + if (DNS_QR(flags)) { + /* this is a response */ + ND_PRINT("%u%s%s%s%s%s%s", + GET_BE_U_2(np->id), + ns_ops[DNS_OPCODE(flags)], + ns_rcode(rcode), + DNS_AA(flags)? "*" : "", + DNS_RA(flags)? "" : "-", + DNS_TC(flags)? "|" : "", + DNS_AD(flags)? "$" : ""); + + if (qdcount != 1) + ND_PRINT(" [%uq]", qdcount); + /* Print QUESTION section on -vv */ + cp = (const u_char *)(np + 1); + for (i = 0; i < qdcount; i++) { + if (i != 0) + ND_PRINT(","); + if (ndo->ndo_vflag > 1) { + ND_PRINT(" q:"); + if ((cp = ns_qprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + } else { + if ((cp = ns_nskip(ndo, cp)) == NULL) + goto trunc; + cp += 4; /* skip QTYPE and QCLASS */ + } + } + ND_PRINT(" %u/%u/%u", ancount, nscount, arcount); + if (ancount) { + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + ancount--; + while (cp < ndo->ndo_snapend && ancount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + ancount--; + } + } + if (ancount) + goto trunc; + /* Print NS and AR sections on -vv */ + if (ndo->ndo_vflag > 1) { + if (cp < ndo->ndo_snapend && nscount) { + ND_PRINT(" ns:"); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + nscount--; + while (cp < ndo->ndo_snapend && nscount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + nscount--; + } + } + if (nscount) + goto trunc; + if (cp < ndo->ndo_snapend && arcount) { + ND_PRINT(" ar:"); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + arcount--; + while (cp < ndo->ndo_snapend && arcount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + arcount--; + } + } + if (arcount) + goto trunc; + } + } + else { + /* this is a request */ + ND_PRINT("%u%s%s%s", GET_BE_U_2(np->id), + ns_ops[DNS_OPCODE(flags)], + DNS_RD(flags) ? "+" : "", + DNS_CD(flags) ? "%" : ""); + + /* any weirdness? */ + b2 = GET_BE_U_2(((const u_short *)np) + 1); + if (b2 & 0x6cf) + ND_PRINT(" [b2&3=0x%x]", b2); + + if (DNS_OPCODE(flags) == IQUERY) { + if (qdcount) + ND_PRINT(" [%uq]", qdcount); + if (ancount != 1) + ND_PRINT(" [%ua]", ancount); + } + else { + if (ancount) + ND_PRINT(" [%ua]", ancount); + if (qdcount != 1) + ND_PRINT(" [%uq]", qdcount); + } + if (nscount) + ND_PRINT(" [%un]", nscount); + if (arcount) + ND_PRINT(" [%uau]", arcount); + + cp = (const u_char *)(np + 1); + if (qdcount) { + cp = ns_qprint(ndo, cp, (const u_char *)np, is_mdns); + if (!cp) + goto trunc; + qdcount--; + while (cp < ndo->ndo_snapend && qdcount) { + cp = ns_qprint(ndo, (const u_char *)cp, + (const u_char *)np, + is_mdns); + if (!cp) + goto trunc; + qdcount--; + } + } + if (qdcount) + goto trunc; + + /* Print remaining sections on -vv */ + if (ndo->ndo_vflag > 1) { + if (ancount) { + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + ancount--; + while (cp < ndo->ndo_snapend && ancount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + ancount--; + } + } + if (ancount) + goto trunc; + if (cp < ndo->ndo_snapend && nscount) { + ND_PRINT(" ns:"); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + nscount--; + while (cp < ndo->ndo_snapend && nscount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + nscount--; + } + } + if (nscount > 0) + goto trunc; + if (cp < ndo->ndo_snapend && arcount) { + ND_PRINT(" ar:"); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + arcount--; + while (cp < ndo->ndo_snapend && arcount) { + ND_PRINT(","); + if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL) + goto trunc; + arcount--; + } + } + if (arcount) + goto trunc; + } + } + ND_PRINT(" (%u)", length); + return; + + trunc: + nd_print_trunc(ndo); +} |