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-rw-r--r--print-domain.c1151
1 files changed, 1151 insertions, 0 deletions
diff --git a/print-domain.c b/print-domain.c
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+++ b/print-domain.c
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+/*
+ * 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 1183 */
+ { 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" },
+ { T_SIG, "SIG" }, /* RFC 2535 */
+ { T_KEY, "KEY" }, /* RFC 2535 */
+ { T_PX, "PX" }, /* RFC 2163 */
+ { T_GPOS, "GPOS" }, /* RFC 1712 */
+ { T_AAAA, "AAAA" }, /* RFC 1886 */
+ { T_LOC, "LOC" }, /* RFC 1876 */
+ { T_NXT, "NXT" }, /* RFC 2535 */
+ { T_EID, "EID" }, /* Nimrod */
+ { T_NIMLOC, "NIMLOC" }, /* Nimrod */
+ { T_SRV, "SRV" }, /* RFC 2782 */
+ { T_ATMA, "ATMA" }, /* ATM Forum */
+ { T_NAPTR, "NAPTR" }, /* RFC 2168, RFC 2915 */
+ { T_KX, "KX" }, /* RFC 2230 */
+ { T_CERT, "CERT" }, /* RFC 2538 */
+ { T_A6, "A6" }, /* RFC 2874 */
+ { T_DNAME, "DNAME" }, /* RFC 2672 */
+ { T_SINK, "SINK" },
+ { T_OPT, "OPT" }, /* RFC 2671 */
+ { 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_SPF, "SPF" }, /* RFC-schlitt-spf-classic-02.txt */
+ { T_UINFO, "UINFO" },
+ { T_UID, "UID" },
+ { T_GID, "GID" },
+ { T_UNSPEC, "UNSPEC" },
+ { T_UNSPECA, "UNSPECA" },
+ { T_TKEY, "TKEY" }, /* RFC 2930 */
+ { T_TSIG, "TSIG" }, /* RFC 2845 */
+ { T_IXFR, "IXFR" }, /* RFC 1995 */
+ { T_AXFR, "AXFR" }, /* RFC 1035 */
+ { T_MAILB, "MAILB" }, /* RFC 1035 */
+ { T_MAILA, "MAILA" }, /* RFC 1035 */
+ { T_ANY, "ANY" },
+ { T_URI, "URI" }, /* RFC 7553 */
+ { 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_UNSPECA: /* One long string */
+ if (!ND_TTEST_LEN(cp, len))
+ return(NULL);
+ if (nd_printn(ndo, cp, len, ndo->ndo_snapend))
+ return(NULL);
+ 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);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 13:52:25 +0000