X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/0c0fca776b174b66460c3f8430b56e663abc4221..HEAD:/print-rt6.c?ds=sidebyside

diff --git a/print-rt6.c b/print-rt6.c
index 096a9628..edbcd96d 100644
--- a/print-rt6.c
+++ b/print-rt6.c
@@ -21,25 +21,112 @@
 
 /* \summary: IPv6 routing header printer */
 
-#ifdef HAVE_CONFIG_H
 #include <config.h>
-#endif
 
 #include "netdissect-stdinc.h"
 
+#define ND_LONGJMP_FROM_TCHECK
 #include "netdissect.h"
 #include "addrtoname.h"
 #include "extract.h"
 
 #include "ip6.h"
 
+static const struct tok srh_tlv_type[] = {
+    { IPV6_SRH_TLV_PAD1, "Pad1"},
+    { IPV6_SRH_TLV_PADN, "PadN"},
+    { IPV6_SRH_TLV_HMAC, "HMAC"},
+    { 0, NULL }
+};
+
+static int
+srh_tlv_print(netdissect_options *ndo, const u_char *p, u_int bytes_left)
+{
+	u_int tlv_type, tlv_len;
+	while (bytes_left != 0) {
+		tlv_type = GET_U_1(p);
+		ND_PRINT(", TLV-type=%s(%u)",
+			 tok2str(srh_tlv_type, "Unknown", tlv_type),
+			 tlv_type);
+		ND_ICHECKMSG_U("remaining length", bytes_left, <, 1);
+		p += 1;
+		bytes_left -= 1;
+		if (bytes_left == 0)
+			break;
+		if (tlv_type == IPV6_SRH_TLV_PAD1)
+			continue;
+
+		tlv_len = GET_U_1(p);
+		ND_PRINT(", TLV-len=%u", tlv_len);
+		ND_ICHECKMSG_U("remaining length", bytes_left, <, 1);
+		p += 1;
+		bytes_left -= 1;
+
+		switch (tlv_type) {
+		case IPV6_SRH_TLV_PADN:
+			ND_ICHECKMSG_U("PadN length", tlv_len, >, 5); /* RFC 8754 */
+			ND_ICHECKMSG_U("remaining length", bytes_left, <, tlv_len);
+			ND_TCHECK_LEN(p, tlv_len);
+			p += tlv_len;
+			bytes_left -= tlv_len;
+			break;
+		case IPV6_SRH_TLV_HMAC:
+			ND_ICHECKMSG_U("remaining length", bytes_left, <, 6);
+			uint16_t reserved;
+			uint32_t key_id;
+			uint8_t hmac_byte;
+			reserved = GET_BE_U_2(p);
+			p += 2;
+			if (ndo->ndo_vflag)
+				ND_PRINT(", D=%u", reserved >> 15);
+			if (ndo->ndo_vflag && (reserved & 0x7fff) != 0)
+				ND_PRINT(", reserved MBZ %u", reserved & 0x7fff);
+			key_id = GET_BE_U_4(p);
+			p += 4;
+			if (ndo->ndo_vflag)
+				ND_PRINT(", HMAC-key-ID=0x%02x", key_id);
+			bytes_left -= 6;
+			if (ndo->ndo_vflag)
+				ND_PRINT(", HMAC=0x");
+			for (u_int i = 0; i < tlv_len; i++) {
+				hmac_byte = GET_U_1(p);
+				ND_ICHECKMSG_U("remaining length", bytes_left, <, 1);
+				p += 1;
+				bytes_left -= 1;
+				if (ndo->ndo_vflag)
+					ND_PRINT("%02x", hmac_byte);
+			}
+			break;
+		default:	/* Unknown type */
+			if (ndo->ndo_vflag)
+				ND_PRINT(", TLV-value=0x");
+			ND_ICHECKMSG_U("remaining length", bytes_left, <, tlv_len);
+			uint8_t tlv_byte;
+			for (u_int i = 0; i < tlv_len; i++) {
+				tlv_byte = GET_U_1(p);
+				p += 1;
+				bytes_left -= 1;
+				if (ndo->ndo_vflag)
+					ND_PRINT("%02x", tlv_byte);
+			}
+			break;
+		}
+	}
+	return 0;
+
+invalid:
+	return -1;
+}
+
+
 int
 rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 {
 	const struct ip6_rthdr *dp;
 	const struct ip6_rthdr0 *dp0;
 	const struct ip6_srh *srh;
-	u_int i, len, type;
+	u_int i, len, type, seg_list_len, last_entry;
+	int err;
 	const u_char *p;
 
 	ndo->ndo_protocol = "rt6";
@@ -66,7 +153,7 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 		}
 
 		if (len % 2 == 1) {
-			ND_PRINT(" (invalid length %u)", len);
+			ND_PRINT(" [length %u]", len);
 			goto invalid;
 		}
 		len >>= 1;
@@ -78,10 +165,10 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 		/*(*/
 		ND_PRINT(") ");
 		return((GET_U_1(dp0->ip6r0_len) + 1) << 3);
-		break;
 	case IPV6_RTHDR_TYPE_4:
 		srh = (const struct ip6_srh *)dp;
-		ND_PRINT(", last-entry=%u", GET_U_1(srh->srh_last_ent));
+		last_entry = GET_U_1(srh->srh_last_ent);
+		ND_PRINT(", last-entry=%u", last_entry);
 
 		if (GET_U_1(srh->srh_flags) || ndo->ndo_vflag) {
 			ND_PRINT(", flags=0x%0x",
@@ -89,21 +176,24 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 		}
 
 		ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
-
-		if (len % 2 == 1) {
-			ND_PRINT(" (invalid length %u)", len);
-			goto invalid;
-		}
-		len >>= 1;
 		p  = (const u_char *) srh->srh_segments;
-		for (i = 0; i < len; i++) {
+		for (i = 0; i < last_entry + 1; i++) {
 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
 			p += 16;
 		}
+		seg_list_len = (last_entry + 1) * 2;
+		if (seg_list_len < len) {
+			/* there is TLV */
+			u_int bytes_left;
+			bytes_left = (len - seg_list_len) * 8;
+			err = srh_tlv_print(ndo, p, bytes_left);
+			if (err)
+				goto invalid;
+		}
+
 		/*(*/
 		ND_PRINT(") ");
 		return((GET_U_1(srh->srh_len) + 1) << 3);
-		break;
 	default:
 		ND_PRINT(" (unknown type)");
 		goto invalid;