X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/49b23c5a9b0198bb382dcf43c458d46fcf2fa809..7ea6b55ab42e1a1b5cd09367f4d1bf2078c93a5d:/print-icmp.c

diff --git a/print-icmp.c b/print-icmp.c
index 17e7a752..0a949518 100644
--- a/print-icmp.c
+++ b/print-icmp.c
@@ -400,7 +400,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 
 			default:
 				(void)snprintf(buf, sizeof(buf),
-					"%s protocol %d port %d unreachable",
+					"%s protocol %u port %u unreachable",
 					ipaddr_string(ndo, &oip->ip_dst),
 					oip->ip_p, dport);
 				break;
@@ -506,7 +506,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 			break;
 
 		default:
-			(void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
+			(void)snprintf(buf, sizeof(buf), "time exceeded-#%u",
 			    dp->icmp_code);
 			break;
 		}
@@ -515,11 +515,11 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 	case ICMP_PARAMPROB:
 		if (dp->icmp_code)
 			(void)snprintf(buf, sizeof(buf),
-			    "parameter problem - code %d", dp->icmp_code);
+			    "parameter problem - code %u", dp->icmp_code);
 		else {
 			ND_TCHECK(dp->icmp_pptr);
 			(void)snprintf(buf, sizeof(buf),
-			    "parameter problem - octet %d", dp->icmp_pptr);
+			    "parameter problem - octet %u", dp->icmp_pptr);
 		}
 		break;
 
@@ -557,14 +557,14 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 	}
 	ND_PRINT((ndo, "ICMP %s, length %u", str, plen));
 	if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
-		uint16_t sum, icmp_sum;
-
 		if (ND_TTEST2(*bp, plen)) {
+			uint16_t sum;
+
 			vec[0].ptr = (const uint8_t *)(const void *)dp;
 			vec[0].len = plen;
 			sum = in_cksum(vec, 1);
 			if (sum != 0) {
-				icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
+				uint16_t icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
 				ND_PRINT((ndo, " (wrong icmp cksum %x (->%x)!)",
 					     icmp_sum,
 					     in_cksum_shouldbe(icmp_sum, sum)));
@@ -580,8 +580,8 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 		bp += 8;
 		ND_PRINT((ndo, "\n\t"));
 		ip = (const struct ip *)bp;
-		ndo->ndo_snaplen = ndo->ndo_snapend - bp;
                 snapend_save = ndo->ndo_snapend;
+		ND_TCHECK_16BITS(&ip->ip_len);
 		ip_print(ndo, bp, EXTRACT_16BITS(&ip->ip_len));
                 ndo->ndo_snapend = snapend_save;
 	}
@@ -599,7 +599,8 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
              * to check if an extension header is present. This is expedient,
              * however not all implementations set the length field proper.
              */
-            if (!ext_dp->icmp_length) {
+            if (!ext_dp->icmp_length &&
+                ND_TTEST2(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) {
                 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
                 vec[0].len = plen - ICMP_EXTD_MINLEN;
                 if (in_cksum(vec, 1)) {
@@ -620,12 +621,14 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
             }
 
             hlen = plen - ICMP_EXTD_MINLEN;
-            vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
-            vec[0].len = hlen;
-            ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u",
-                   EXTRACT_16BITS(ext_dp->icmp_ext_checksum),
-                   in_cksum(vec, 1) ? "in" : "",
-                   hlen));
+            if (ND_TTEST2(ext_dp->icmp_ext_version_res, hlen)) {
+                vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
+                vec[0].len = hlen;
+                ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u",
+                       EXTRACT_16BITS(ext_dp->icmp_ext_checksum),
+                       in_cksum(vec, 1) ? "in" : "",
+                       hlen));
+            }
 
             hlen -= 4; /* subtract common header size */
             obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data;