snprintf madness

1 files changed, 29 insertions, 23 deletions

diff --git a/usr.sbin/tcpdump/print-icmp.c b/usr.sbin/tcpdump/print-icmp.c
index 8a8ae08b774..091752111ed 100644
--- a/usr.sbin/tcpdump/print-icmp.c
+++ b/usr.sbin/tcpdump/print-icmp.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /home/cvs/src/usr.sbin/tcpdump/print-icmp.c,v 1.6 1997/07/25 20:12:24 mickey Exp $ (LBL)";
+    "@(#) $Header: /home/cvs/src/usr.sbin/tcpdump/print-icmp.c,v 1.7 1998/07/13 22:13:47 deraadt Exp $ (LBL)";
 #endif
 
 #include <sys/param.h>
@@ -172,7 +172,7 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 	register const struct ip *oip;
 	register const struct udphdr *ouh;
 	register u_int hlen, dport, mtu;
-	char buf[256];
+	char buf[MAXHOSTNAMELEN+256];
 
 	dp = (struct icmp *)bp;
 	ip = (struct ip *)bp2;
@@ -191,7 +191,8 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 
 		case ICMP_UNREACH_PROTOCOL:
 			TCHECK(dp->icmp_ip.ip_p);
-			(void)sprintf(buf, "%s protocol %d unreachable",
+			(void)snprintf(buf, sizeof buf,
+				       "%s protocol %d unreachable",
 				       ipaddr_string(&dp->icmp_ip.ip_dst),
 				       dp->icmp_ip.ip_p);
 			break;
@@ -205,21 +206,21 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 			switch (oip->ip_p) {
 
 			case IPPROTO_TCP:
-				(void)sprintf(buf,
+				(void)snprintf(buf, sizeof buf,
 					"%s tcp port %s unreachable",
 					ipaddr_string(&oip->ip_dst),
 					tcpport_string(dport));
 				break;
 
 			case IPPROTO_UDP:
-				(void)sprintf(buf,
+				(void)snprintf(buf, sizeof buf,
 					"%s udp port %s unreachable",
 					ipaddr_string(&oip->ip_dst),
 					udpport_string(dport));
 				break;
 
 			default:
-				(void)sprintf(buf,
+				(void)snprintf(buf, sizeof buf,
 					"%s protocol %d port %d unreachable",
 					ipaddr_string(&oip->ip_dst),
 					oip->ip_p, dport);
@@ -234,11 +235,11 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 			mp = (struct mtu_discovery *)&dp->icmp_void;
                         mtu = EXTRACT_16BITS(&mp->nexthopmtu);
                         if (mtu)
-			    (void)sprintf(buf,
+			    (void)snprintf(buf, sizeof buf,
 				"%s unreachable - need to frag (mtu %d)",
 				ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
                         else
-			    (void)sprintf(buf,
+			    (void)snprintf(buf, sizeof buf,
 				"%s unreachable - need to frag",
 				ipaddr_string(&dp->icmp_ip.ip_dst));
 			}
@@ -247,7 +248,7 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 		default:
 			fmt = tok2str(unreach2str, "#%d %%s unreachable",
 			    dp->icmp_code);
-			(void)sprintf(buf, fmt,
+			(void)snprintf(buf, sizeof buf, fmt,
 			    ipaddr_string(&dp->icmp_ip.ip_dst));
 			break;
 		}
@@ -257,7 +258,7 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 		TCHECK(dp->icmp_ip.ip_dst);
 		fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
 		    dp->icmp_code);
-		(void)sprintf(buf, fmt,
+		(void)snprintf(buf, sizeof buf, fmt,
 		    ipaddr_string(&dp->icmp_ip.ip_dst),
 		    ipaddr_string(&dp->icmp_gwaddr));
 		break;
@@ -268,7 +269,8 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 		register const struct id_rdiscovery *idp;
 		u_int lifetime, num, size;
 
-		(void)strcpy(buf, "router advertisement");
+		(void)strncpy(buf, "router advertisement", sizeof buf-1);
+		buf[sizeof buf-1] = '\0';
 		cp = buf + strlen(buf);
 
 		ihp = (struct ih_rdiscovery *)&dp->icmp_void;
@@ -277,30 +279,31 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 		cp = buf + strlen(buf);
 		lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
 		if (lifetime < 60)
-			(void)sprintf(cp, "%u", lifetime);
+			(void)snprintf(cp, buf + sizeof buf - cp, "%u", lifetime);
 		else if (lifetime < 60 * 60)
-			(void)sprintf(cp, "%u:%02u",
+			(void)snprintf(cp, buf + sizeof buf - cp, "%u:%02u",
 			    lifetime / 60, lifetime % 60);
 		else
-			(void)sprintf(cp, "%u:%02u:%02u",
+			(void)snprintf(cp, buf + sizeof buf - cp, "%u:%02u:%02u",
 			    lifetime / 3600,
 			    (lifetime % 3600) / 60,
 			    lifetime % 60);
 		cp = buf + strlen(buf);
 
 		num = ihp->ird_addrnum;
-		(void)sprintf(cp, " %d:", num);
+		(void)snprintf(cp, buf + sizeof buf - cp, " %d:", num);
 		cp = buf + strlen(buf);
 
 		size = ihp->ird_addrsiz;
 		if (size != 2) {
-			(void)sprintf(cp, " [size %d]", size);
+			(void)snprintf(cp, buf - sizeof buf - cp,
+				" [size %d]", size);
 			break;
 		}
 		idp = (struct id_rdiscovery *)&dp->icmp_data;
 		while (num-- > 0) {
 			TCHECK(*idp);
-			(void)sprintf(cp, " {%s %u}",
+			(void)snprintf(cp, buf + sizeof buf - cp, " {%s %u}",
 			    ipaddr_string(&idp->ird_addr),
 			    EXTRACT_32BITS(&idp->ird_pref));
 			cp = buf + strlen(buf);
@@ -321,25 +324,28 @@ icmp_print(register const u_char *bp, register const u_char *bp2)
 			break;
 
 		default:
-			(void)sprintf(buf, "time exceeded-#%d", dp->icmp_code);
+			(void)snprintf(buf, sizeof buf,
+				"time exceeded-#%d", dp->icmp_code);
 			break;
 		}
 		break;
 
 	case ICMP_PARAMPROB:
 		if (dp->icmp_code)
-			(void)sprintf(buf, "parameter problem - code %d",
-					dp->icmp_code);
+			(void)snprintf(buf, sizeof buf,
+				"parameter problem - code %d",
+				dp->icmp_code);
 		else {
 			TCHECK(dp->icmp_pptr);
-			(void)sprintf(buf, "parameter problem - octet %d",
-					dp->icmp_pptr);
+			(void)snprintf(buf, sizeof buf,
+				"parameter problem - octet %d",
+				dp->icmp_pptr);
 		}
 		break;
 
 	case ICMP_MASKREPLY:
 		TCHECK(dp->icmp_mask);
-		(void)sprintf(buf, "address mask is 0x%08x",
+		(void)snprintf(buf, sizeof buf, "address mask is 0x%08x",
 		    (u_int32_t)ntohl(dp->icmp_mask));
 		break;