X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/b751376719cfe1924aa07ab8fd364ec1a55c04b3..c39d40a767a1ae36171e5bcbf6f157ff3e80fb6c:/print-domain.c

diff --git a/print-domain.c b/print-domain.c
index 28c7f2b9..dcfc9fd2 100644
--- a/print-domain.c
+++ b/print-domain.c
@@ -74,12 +74,15 @@ ns_nskip(netdissect_options *ndo,
 	i = GET_U_1(cp);
 	cp++;
 	while (i) {
-		if ((i & INDIR_MASK) == INDIR_MASK)
+		switch (i & TYPE_MASK) {
+
+		case TYPE_INDIR:
 			return (cp + 1);
-		if ((i & INDIR_MASK) == EDNS0_MASK) {
+
+		case TYPE_EDNS0: {
 			int bitlen, bytelen;
 
-			if ((i & ~INDIR_MASK) != EDNS0_ELT_BITLABEL)
+			if ((i & ~TYPE_MASK) != EDNS0_ELT_BITLABEL)
 				return(NULL); /* unknown ELT */
 			if (!ND_TTEST_1(cp))
 				return (NULL);
@@ -88,8 +91,16 @@ ns_nskip(netdissect_options *ndo,
 			cp++;
 			bytelen = (bitlen + 7) / 8;
 			cp += bytelen;
-		} else
+		}
+		break;
+
+		case TYPE_RESERVED:
+			return (NULL);
+
+		case TYPE_LABEL:
 			cp += i;
+			break;
+		}
 		if (!ND_TTEST_1(cp))
 			return (NULL);
 		i = GET_U_1(cp);
@@ -116,25 +127,19 @@ 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
@@ -146,9 +151,11 @@ labellen(netdissect_options *ndo,
 	if (!ND_TTEST_1(cp))
 		return(-1);
 	i = GET_U_1(cp);
-	if ((i & INDIR_MASK) == EDNS0_MASK) {
+	switch (i & TYPE_MASK) {
+
+	case TYPE_EDNS0: {
 		u_int bitlen, elt;
-		if ((elt = (i & ~INDIR_MASK)) != EDNS0_ELT_BITLABEL) {
+		if ((elt = (i & ~TYPE_MASK)) != EDNS0_ELT_BITLABEL) {
 			ND_PRINT("<ELT %d>", elt);
 			return(-1);
 		}
@@ -157,8 +164,20 @@ labellen(netdissect_options *ndo,
 		if ((bitlen = GET_U_1(cp + 1)) == 0)
 			bitlen = 256;
 		return(((bitlen + 7) / 8) + 1);
-	} else
+	}
+
+	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> */
@@ -171,6 +190,7 @@ fqdn_print(netdissect_options *ndo,
 	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);
@@ -179,14 +199,16 @@ fqdn_print(netdissect_options *ndo,
 	max_offset = (u_int)(cp - bp);
 	i = GET_U_1(cp);
 	cp++;
-	if ((i & INDIR_MASK) != INDIR_MASK) {
+	if ((i & TYPE_MASK) != TYPE_INDIR) {
 		compress = 0;
 		rp = cp + l;
 	}
 
-	if (i != 0)
+	if (i != 0) {
 		while (i && cp < ndo->ndo_snapend) {
-			if ((i & INDIR_MASK) == INDIR_MASK) {
+			switch (i & TYPE_MASK) {
+
+			case TYPE_INDIR:
 				if (!compress) {
 					rp = cp + 1;
 					compress = 1;
@@ -210,16 +232,16 @@ fqdn_print(netdissect_options *ndo,
 				}
 				max_offset = offset;
 				cp = bp + offset;
-				if ((l = labellen(ndo, cp)) == (u_int)-1)
-					return(NULL);
 				if (!ND_TTEST_1(cp))
 					return(NULL);
 				i = GET_U_1(cp);
+				if ((l = labellen(ndo, cp)) == (u_int)-1)
+					return(NULL);
 				cp++;
 				continue;
-			}
-			if ((i & INDIR_MASK) == EDNS0_MASK) {
-				elt = (i & ~INDIR_MASK);
+
+			case TYPE_EDNS0:
+				elt = (i & ~TYPE_MASK);
 				switch(elt) {
 				case EDNS0_ELT_BITLABEL:
 					if (blabel_print(ndo, cp) == NULL)
@@ -230,23 +252,41 @@ fqdn_print(netdissect_options *ndo,
 					ND_PRINT("<ELT %u>", elt);
 					return(NULL);
 				}
-			} else {
-				if (nd_printn(ndo, cp, l, ndo->ndo_snapend))
-					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;
-			ND_PRINT(".");
-			if ((l = labellen(ndo, cp)) == (u_int)-1)
-				return(NULL);
+			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;
 		}
-	else
+		if (name_chars > MAXCDNAME)
+			ND_PRINT("<DOMAIN NAME TOO LONG>");
+	} else
 		ND_PRINT(".");
 	return (rp);
 }
@@ -455,30 +495,30 @@ const struct tok ns_type2str[] = {
 	{ T_MX,		"MX" },			/* RFC 1035 */
 	{ T_TXT,	"TXT" },		/* RFC 1035 */
 	{ T_RP,		"RP" },			/* RFC 1183 */
-	{ T_AFSDB,	"AFSDB" },		/* 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" },
-	{ T_SIG,	"SIG" },		/* RFC 2535 */
-	{ T_KEY,	"KEY" },		/* RFC 2535 */
+	{ 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 1886 */
+	{ T_AAAA,	"AAAA" },		/* RFC 3596 */
 	{ T_LOC,	"LOC" },		/* RFC 1876 */
-	{ T_NXT,	"NXT" },		/* RFC 2535 */
+	{ 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 2168, RFC 2915 */
+	{ T_NAPTR,	"NAPTR" },		/* RFC 3403 */
 	{ T_KX,		"KX" },			/* RFC 2230 */
-	{ T_CERT,	"CERT" },		/* RFC 2538 */
-	{ T_A6,		"A6" },			/* RFC 2874 */
-	{ T_DNAME,	"DNAME" },		/* RFC 2672 */
+	{ T_CERT,	"CERT" },		/* RFC 4398 */
+	{ T_A6,		"A6" },			/* RFC 6563 */
+	{ T_DNAME,	"DNAME" },		/* RFC 6672 */
 	{ T_SINK, 	"SINK" },
-	{ T_OPT,	"OPT" },		/* RFC 2671 */
+	{ T_OPT,	"OPT" },		/* RFC 6891 */
 	{ T_APL, 	"APL" },		/* RFC 3123 */
 	{ T_DS,		"DS" },			/* RFC 4034 */
 	{ T_SSHFP,	"SSHFP" },		/* RFC 4255 */
@@ -486,20 +526,47 @@ const struct tok ns_type2str[] = {
 	{ 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_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_UNSPECA,	"UNSPECA" },
+	{ 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 2845 */
+	{ T_TSIG,	"TSIG" },		/* RFC 8945 */
 	{ T_IXFR,	"IXFR" },		/* RFC 1995 */
-	{ T_AXFR,	"AXFR" },		/* RFC 1035 */
+	{ T_AXFR,	"AXFR" },		/* RFC 5936 */
 	{ T_MAILB,	"MAILB" },		/* RFC 1035 */
 	{ T_MAILA,	"MAILA" },		/* RFC 1035 */
-	{ T_ANY,	"ANY" },
+	{ 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 }
 };
 
@@ -673,9 +740,7 @@ ns_rprint(netdissect_options *ndo,
 	case T_NS:
 	case T_CNAME:
 	case T_PTR:
-#ifdef T_DNAME
 	case T_DNAME:
-#endif
 		ND_PRINT(" ");
 		if (fqdn_print(ndo, cp, bp) == NULL)
 			return(NULL);
@@ -758,10 +823,8 @@ ns_rprint(netdissect_options *ndo,
 			ND_PRINT(" %u(bad plen)", pbit);
 			break;
 		} else if (pbit < 128) {
-			if (!ND_TTEST_LEN(cp + 1, sizeof(a) - pbyte))
-				return(NULL);
 			memset(a, 0, sizeof(a));
-			memcpy(a + pbyte, cp + 1, sizeof(a) - pbyte);
+			GET_CPY_BYTES(a + pbyte, cp + 1, sizeof(a) - pbyte);
 			ND_PRINT(" %u %s", pbit,
 			    addrtostr6(&a, ntop_buf, sizeof(ntop_buf)));
 		}
@@ -798,13 +861,6 @@ ns_rprint(netdissect_options *ndo,
         }
 		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)
@@ -842,7 +898,7 @@ 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;
@@ -852,6 +908,34 @@ 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)) {
@@ -900,7 +984,7 @@ 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;