From: Guy Harris <guy@alum.mit.edu>
Date: Thu, 3 Oct 2019 18:13:37 +0000 (-0700)
Subject: Use pcap_strlcpy() when copying a string to a fixed-length buffer.
X-Git-Tag: libpcap-1.10-bp~410
X-Git-Url: https://git.tcpdump.org/libpcap/commitdiff_plain/fb4f0f1c85560e65cee6c6f6ba0addb2fc468136

Use pcap_strlcpy() when copying a string to a fixed-length buffer.

That makes sure we terminate with a '\0'.

Reported by Charles Smith at Tangible Security.

While we're at it, fix some existing pcap_strlcpy() calls to use the
size of the buffer, using sizeof.
---

diff --git a/rpcapd/fileconf.c b/rpcapd/fileconf.c
index 76d59334..b79dda18 100644
--- a/rpcapd/fileconf.c
+++ b/rpcapd/fileconf.c
@@ -507,8 +507,7 @@ int fileconf_save(const char *savefile)
 		fprintf(fp, "# Hosts which are allowed to connect to this server (passive mode)\n");
 		fprintf(fp, "# Format: PassiveClient = <name or address>\n\n");
 
-		strncpy(temphostlist, hostlist, MAX_HOST_LIST);
-		temphostlist[MAX_HOST_LIST] = 0;
+		pcap_strlcpy(temphostlist, hostlist, sizeof (temphostlist));
 
 		token = pcap_strtok_r(temphostlist, RPCAP_HOSTLIST_SEP, &lasts);
 		while(token != NULL)
diff --git a/rpcapd/rpcapd.c b/rpcapd/rpcapd.c
index 5b6c14cd..ecb88955 100644
--- a/rpcapd/rpcapd.c
+++ b/rpcapd/rpcapd.c
@@ -194,8 +194,8 @@ int main(int argc, char *argv[])
 	// Initialize errbuf
 	memset(errbuf, 0, sizeof(errbuf));
 
-	strncpy(address, RPCAP_DEFAULT_NETADDR, MAX_LINE);
-	strncpy(port, RPCAP_DEFAULT_NETPORT, MAX_LINE);
+	pcap_strlcpy(address, RPCAP_DEFAULT_NETADDR, sizeof (address));
+	pcap_strlcpy(port, RPCAP_DEFAULT_NETPORT, sizeof (port));
 
 	// Prepare to open a new server socket
 	memset(&mainhints, 0, sizeof(struct addrinfo));
@@ -222,10 +222,10 @@ int main(int argc, char *argv[])
 				rpcapd_log_set(log_to_systemlog, log_debug_messages);
 				break;
 			case 'b':
-				strncpy(address, optarg, MAX_LINE);
+				pcap_strlcpy(address, optarg, sizeof (address));
 				break;
 			case 'p':
-				strncpy(port, optarg, MAX_LINE);
+				pcap_strlcpy(port, optarg, sizeof (port));
 				break;
 			case '4':
 				mainhints.ai_family = PF_INET;		// IPv4 server only
@@ -253,7 +253,7 @@ int main(int argc, char *argv[])
 				break;
 			case 'l':
 			{
-				strncpy(hostlist, optarg, sizeof(hostlist));
+				pcap_strlcpy(hostlist, optarg, sizeof(hostlist));
 				break;
 			}
 			case 'a':
@@ -268,12 +268,12 @@ int main(int argc, char *argv[])
 				{
 					tmpport = pcap_strtok_r(NULL, RPCAP_HOSTLIST_SEP, &lasts);
 
-					pcap_strlcpy(activelist[i].address, tmpaddress, MAX_LINE);
+					pcap_strlcpy(activelist[i].address, tmpaddress, sizeof (activelist[i].address));
 
 					if ((tmpport == NULL) || (strcmp(tmpport, "DEFAULT") == 0)) // the user choose a custom port
-						pcap_strlcpy(activelist[i].port, RPCAP_DEFAULT_NETPORT_ACTIVE, MAX_LINE);
+						pcap_strlcpy(activelist[i].port, RPCAP_DEFAULT_NETPORT_ACTIVE, sizeof (activelist[i].port));
 					else
-						pcap_strlcpy(activelist[i].port, tmpport, MAX_LINE);
+						pcap_strlcpy(activelist[i].port, tmpport, sizeof (activelist[i].port));
 
 					tmpaddress = pcap_strtok_r(NULL, RPCAP_HOSTLIST_SEP, &lasts);
 
@@ -288,10 +288,10 @@ int main(int argc, char *argv[])
 				break;
 			}
 			case 'f':
-				pcap_strlcpy(loadfile, optarg, MAX_LINE);
+				pcap_strlcpy(loadfile, optarg, sizeof (loadfile));
 				break;
 			case 's':
-				pcap_strlcpy(savefile, optarg, MAX_LINE);
+				pcap_strlcpy(savefile, optarg, sizeof (savefile));
 				break;
 #ifdef HAVE_OPENSSL
 			case 'S':