rpcap: reduce timeout on socket connect

Allow to set a custom timeout to the connect to avoid waiting minutes for nothing should the connect() call fail. Signed-off-by: Kevin Boulain <[email protected]> Signed-off-by: Gabriel Ganne <[email protected]>
the-tcpdump-group · Feb 14, 2022 · 7728304 · 7728304
1 parent b3d6978
commit 7728304
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Showing 6 changed files with 34 additions and 10 deletions.
diff --git a/pcap-int.h b/pcap-int.h
@@ -362,6 +362,8 @@ struct pcap {
 	get_airpcap_handle_op_t get_airpcap_handle_op;
 #endif
 	cleanup_op_t cleanup_op;
+
+	unsigned int sock_open_timeout;
 };
 
 /*

diff --git a/pcap-rpcap.c b/pcap-rpcap.c
@@ -1198,7 +1198,8 @@ static int pcap_startcapture_remote(pcap_t *fp)
 			goto error_nodiscard;
 
 		if ((sockdata = sock_open(addrinfo, SOCKOPEN_SERVER,
-			1 /* max 1 connection in queue */, fp->errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+			1 /* max 1 connection in queue */, fp->errbuf, PCAP_ERRBUF_SIZE,
+			fp->sock_open_timeout)) == INVALID_SOCKET)
 			goto error_nodiscard;
 
 		/* addrinfo is no longer used */
@@ -1321,7 +1322,8 @@ static int pcap_startcapture_remote(pcap_t *fp)
 			if (sock_initaddress(host, portstring, &hints, &addrinfo, fp->errbuf, PCAP_ERRBUF_SIZE) == -1)
 				goto error;
 
-			if ((sockdata = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, fp->errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+			if ((sockdata = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, fp->errbuf, PCAP_ERRBUF_SIZE,
+								fp->sock_open_timeout)) == INVALID_SOCKET)
 				goto error;
 
 			/* addrinfo is no longer used */
@@ -2273,7 +2275,7 @@ rpcap_setup_session(const char *source, struct pcap_rmtauth *auth,
 		}
 
 		if ((*sockctrlp = sock_open(addrinfo, SOCKOPEN_CLIENT, 0,
-		    errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+		    errbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 		{
 			freeaddrinfo(addrinfo);
 			return -1;
@@ -2880,7 +2882,7 @@ SOCKET pcap_remoteact_accept_ex(const char *address, const char *port, const cha
 	}
 
 
-	if ((sockmain = sock_open(addrinfo, SOCKOPEN_SERVER, 1, errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+	if ((sockmain = sock_open(addrinfo, SOCKOPEN_SERVER, 1, errbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 	{
 		freeaddrinfo(addrinfo);
 		return (SOCKET)-2;

diff --git a/rpcapd/daemon.c b/rpcapd/daemon.c
@@ -2078,7 +2078,7 @@ daemon_msg_startcap_req(uint8 ver, struct daemon_slpars *pars, uint32 plen,
 		if (sock_initaddress(peerhost, portdata, &hints, &addrinfo, errmsgbuf, PCAP_ERRBUF_SIZE) == -1)
 			goto error;
 
-		if ((session->sockdata = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, errmsgbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+		if ((session->sockdata = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, errmsgbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 			goto error;
 	}
 	else		// Data connection is opened by the client toward the server
@@ -2089,7 +2089,7 @@ daemon_msg_startcap_req(uint8 ver, struct daemon_slpars *pars, uint32 plen,
 		if (sock_initaddress(NULL, "0", &hints, &addrinfo, errmsgbuf, PCAP_ERRBUF_SIZE) == -1)
 			goto error;
 
-		if ((session->sockdata = sock_open(addrinfo, SOCKOPEN_SERVER, 1 /* max 1 connection in queue */, errmsgbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+		if ((session->sockdata = sock_open(addrinfo, SOCKOPEN_SERVER, 1 /* max 1 connection in queue */, errmsgbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 			goto error;
 
 		// get the complete sockaddr structure used in the data connection

diff --git a/rpcapd/rpcapd.c b/rpcapd/rpcapd.c
@@ -623,7 +623,7 @@ void main_startup(void)
 			SOCKET sock;
 			struct listen_sock *sock_info;
 
-			if ((sock = sock_open(tempaddrinfo, SOCKOPEN_SERVER, SOCKET_MAXCONN, errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+			if ((sock = sock_open(tempaddrinfo, SOCKOPEN_SERVER, SOCKET_MAXCONN, errbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 			{
 				switch (tempaddrinfo->ai_family)
 				{
@@ -1358,7 +1358,7 @@ main_active(void *ptr)
 	{
 		int activeclose;
 
-		if ((sockctrl = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
+		if ((sockctrl = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, errbuf, PCAP_ERRBUF_SIZE, 0)) == INVALID_SOCKET)
 		{
 			rpcapd_log(LOGPRIO_DEBUG, "%s", errbuf);
 

diff --git a/sockutils.c b/sockutils.c
@@ -312,7 +312,7 @@ static int sock_ismcastaddr(const struct sockaddr *saddr)
  * if everything is fine, INVALID_SOCKET if some errors occurred. The error message is returned
  * in the 'errbuf' variable.
  */
-SOCKET sock_open(struct addrinfo *addrinfo, int server, int nconn, char *errbuf, int errbuflen)
+SOCKET sock_open(struct addrinfo *addrinfo, int server, int nconn, char *errbuf, int errbuflen, unsigned int timeout_sec)
 {
 	SOCKET sock;
 #if defined(SO_NOSIGPIPE) || defined(IPV6_V6ONLY) || defined(IPV6_BINDV6ONLY)
@@ -422,6 +422,26 @@ SOCKET sock_open(struct addrinfo *addrinfo, int server, int nconn, char *errbuf,
 	}
 	else	/* we're the client */
 	{
+		/* Customize some timeouts to avoid minutes of waiting for nothing.
+		 * Keep the defaults if unset. */
+		if (timeout_sec != 0) {
+			struct timeval timeout = { 0 };
+			timeout.tv_sec = timeout_sec;
+			if (setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout)) < 0)
+			{
+				sock_geterror("socket(): ", errbuf, errbuflen);
+				closesocket(sock);
+				return INVALID_SOCKET;
+			}
+			/* needed for the first syn */
+			if (setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (char *)&timeout, sizeof(timeout)) < 0)
+			{
+				sock_geterror("socket(): ", errbuf, errbuflen);
+				closesocket(sock);
+				return INVALID_SOCKET;
+			}
+		}
+
 		struct addrinfo *tempaddrinfo;
 		char *errbufptr;
 		size_t bufspaceleft;

diff --git a/sockutils.h b/sockutils.h
@@ -136,7 +136,7 @@ int sock_recv(SOCKET sock, SSL *, void *buffer, size_t size, int receiveall,
     char *errbuf, int errbuflen);
 int sock_recv_dgram(SOCKET sock, SSL *, void *buffer, size_t size,
     char *errbuf, int errbuflen);
-SOCKET sock_open(struct addrinfo *addrinfo, int server, int nconn, char *errbuf, int errbuflen);
+SOCKET sock_open(struct addrinfo *addrinfo, int server, int nconn, char *errbuf, int errbuflen, unsigned int timeout_sec);
 int sock_close(SOCKET sock, char *errbuf, int errbuflen);
 
 int sock_send(SOCKET sock, SSL *, const char *buffer, size_t size,