X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet_packet.c;h=b444bc9310277605e4bec46108f25bd578eeba0f;hb=a22041922f160667573e9a5ae3f4195e1668906a;hp=3243670295d7cb747299488f24f96f20c46117f1;hpb=c11dc8079b60d9f8c5b1c7e8fecd90d0fac5a20c;p=tinc

diff --git a/src/net_packet.c b/src/net_packet.c
index 32436702..b444bc93 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -1,7 +1,8 @@
 /*
     net_packet.c -- Handles in- and outgoing VPN packets
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2009 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2010 Guus Sliepen <guus@tinc-vpn.org>
+                  2010      Timothy Redaelli <timothy@redaelli.eu>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -26,15 +27,22 @@
 #include <openssl/pem.h>
 #include <openssl/hmac.h>
 
+#ifdef HAVE_ZLIB
 #include <zlib.h>
+#endif
+
+#ifdef HAVE_LZO
 #include LZO1X_H
+#endif
 
-#include "avl_tree.h"
+#include "splay_tree.h"
+#include "cipher.h"
 #include "conf.h"
 #include "connection.h"
+#include "crypto.h"
+#include "digest.h"
 #include "device.h"
 #include "ethernet.h"
-#include "event.h"
 #include "graph.h"
 #include "list.h"
 #include "logger.h"
@@ -46,21 +54,11 @@
 #include "utils.h"
 #include "xalloc.h"
 
-#ifdef HAVE_MINGW
-#include <winerror.h>
-#define EMSGSIZE WSAEMSGSIZE
-#define EAGAIN WSATRY_AGAIN
-#define EINTR WSAEINTR
-#define sockstrerror(x) winerror(x)
-#define sockerrno WSAGetLastError()
-#else
-#define sockstrerror(x) strerror(x)
-#define sockerrno errno
-#endif
-
 int keylifetime = 0;
 int keyexpires = 0;
+#ifdef HAVE_LZO
 static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
+#endif
 
 static void send_udppacket(node_t *, vpn_packet_t *);
 
@@ -71,13 +69,13 @@ static void send_udppacket(node_t *, vpn_packet_t *);
 // mtuprobes ==    32: send 1 burst, sleep pingtimeout second
 // mtuprobes ==    33: no response from other side, restart PMTU discovery process
 
-void send_mtu_probe(node_t *n) {
+static void send_mtu_probe_handler(int fd, short events, void *data) {
+	node_t *n = data;
 	vpn_packet_t packet;
 	int len, i;
 	int timeout = 1;
 	
 	n->mtuprobes++;
-	n->mtuevent = NULL;
 
 	if(!n->status.reachable || !n->status.validkey) {
 		ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname);
@@ -125,7 +123,7 @@ void send_mtu_probe(node_t *n) {
 			len = 64;
 		
 		memset(packet.data, 0, 14);
-		RAND_pseudo_bytes(packet.data + 14, len - 14);
+		randomize(packet.data + 14, len - 14);
 		packet.len = len;
 		packet.priority = 0;
 
@@ -135,11 +133,13 @@ void send_mtu_probe(node_t *n) {
 	}
 
 end:
-	n->mtuevent = new_event();
-	n->mtuevent->handler = (event_handler_t)send_mtu_probe;
-	n->mtuevent->data = n;
-	n->mtuevent->time = now + timeout;
-	event_add(n->mtuevent);
+	event_add(&n->mtuevent, &(struct timeval){timeout, 0});
+}
+
+void send_mtu_probe(node_t *n) {
+	if(!timeout_initialized(&n->mtuevent))
+		timeout_set(&n->mtuevent, send_mtu_probe_handler, n);
+	send_mtu_probe_handler(0, 0, n);
 }
 
 void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
@@ -159,40 +159,61 @@ void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 }
 
 static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
-	if(level == 10) {
+	if(level == 0) {
+		memcpy(dest, source, len);
+		return len;
+	} else if(level == 10) {
+#ifdef HAVE_LZO
 		lzo_uint lzolen = MAXSIZE;
 		lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
 		return lzolen;
+#else
+		return -1;
+#endif
 	} else if(level < 10) {
+#ifdef HAVE_ZLIB
 		unsigned long destlen = MAXSIZE;
 		if(compress2(dest, &destlen, source, len, level) == Z_OK)
 			return destlen;
 		else
+#endif
 			return -1;
 	} else {
+#ifdef HAVE_LZO
 		lzo_uint lzolen = MAXSIZE;
 		lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
 		return lzolen;
+#else
+		return -1;
+#endif
 	}
 	
 	return -1;
 }
 
 static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
-	if(level > 9) {
+	if(level == 0) {
+		memcpy(dest, source, len);
+		return len;
+	} else if(level > 9) {
+#ifdef HAVE_LZO
 		lzo_uint lzolen = MAXSIZE;
 		if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
 			return lzolen;
 		else
+#endif
 			return -1;
-	} else {
+	}
+#ifdef HAVE_ZLIB
+	else {
 		unsigned long destlen = MAXSIZE;
 		if(uncompress(dest, &destlen, source, len) == Z_OK)
 			return destlen;
 		else
 			return -1;
 	}
-	
+#endif
+
 	return -1;
 }
 
@@ -205,15 +226,11 @@ static void receive_packet(node_t *n, vpn_packet_t *packet) {
 	route(n, packet);
 }
 
-static bool try_mac(const node_t *n, const vpn_packet_t *inpkt) {
-	unsigned char hmac[EVP_MAX_MD_SIZE];
-
-	if(!n->indigest || !n->inmaclength || !n->inkey || inpkt->len < sizeof inpkt->seqno + n->inmaclength)
+static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
+	if(!digest_active(&n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest))
 		return false;
 
-	HMAC(n->indigest, n->inkey, n->inkeylength, (unsigned char *) &inpkt->seqno, inpkt->len - n->inmaclength, (unsigned char *)hmac, NULL);
-
-	return !memcmp(hmac, (char *) &inpkt->seqno + inpkt->len - n->inmaclength, n->inmaclength);
+	return digest_verify(&n->indigest, &inpkt->seqno, inpkt->len - n->indigest.maclength, (const char *)&inpkt->seqno + inpkt->len - n->indigest.maclength);
 }
 
 static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
@@ -221,11 +238,10 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 	vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 	int nextpkt = 0;
 	vpn_packet_t *outpkt = pkt[0];
-	int outlen, outpad;
-	unsigned char hmac[EVP_MAX_MD_SIZE];
+	size_t outlen;
 	int i;
 
-	if(!n->inkey) {
+	if(!cipher_active(&n->incipher)) {
 		ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
 					n->name, n->hostname);
 		return;
@@ -233,7 +249,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 
 	/* Check packet length */
 
-	if(inpkt->len < sizeof(inpkt->seqno) + n->inmaclength) {
+	if(inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest)) {
 		ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)",
 					n->name, n->hostname);
 		return;
@@ -241,66 +257,58 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 
 	/* Check the message authentication code */
 
-	if(n->indigest && n->inmaclength) {
-		inpkt->len -= n->inmaclength;
-		HMAC(n->indigest, n->inkey, n->inkeylength,
-			 (unsigned char *) &inpkt->seqno, inpkt->len, (unsigned char *)hmac, NULL);
-
-		if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, n->inmaclength)) {
-			ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)",
-					   n->name, n->hostname);
+	if(digest_active(&n->indigest)) {
+		inpkt->len -= n->indigest.maclength;
+ 		if(!digest_verify(&n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) {
+			ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname);
 			return;
 		}
 	}
-
 	/* Decrypt the packet */
 
-	if(n->incipher) {
+	if(cipher_active(&n->incipher)) {
 		outpkt = pkt[nextpkt++];
+		outlen = MAXSIZE;
 
-		if(!EVP_DecryptInit_ex(&n->inctx, NULL, NULL, NULL, NULL)
-				|| !EVP_DecryptUpdate(&n->inctx, (unsigned char *) &outpkt->seqno, &outlen,
-					(unsigned char *) &inpkt->seqno, inpkt->len)
-				|| !EVP_DecryptFinal_ex(&n->inctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) {
-			ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s): %s",
-						n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
+		if(!cipher_decrypt(&n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
+			ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname);
 			return;
 		}
 		
-		outpkt->len = outlen + outpad;
+		outpkt->len = outlen;
 		inpkt = outpkt;
 	}
 
 	/* Check the sequence number */
 
-	inpkt->len -= sizeof(inpkt->seqno);
+	inpkt->len -= sizeof inpkt->seqno;
 	inpkt->seqno = ntohl(inpkt->seqno);
 
 	if(inpkt->seqno != n->received_seqno + 1) {
-		if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) {
+		if(inpkt->seqno >= n->received_seqno + sizeof n->late * 8) {
 			logger(LOG_WARNING, "Lost %d packets from %s (%s)",
 					   inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
 			
-			memset(n->late, 0, sizeof(n->late));
+			memset(n->late, 0, sizeof n->late);
 		} else if (inpkt->seqno <= n->received_seqno) {
-			if((n->received_seqno >= sizeof(n->late) * 8 && inpkt->seqno <= n->received_seqno - sizeof(n->late) * 8) || !(n->late[(inpkt->seqno / 8) % sizeof(n->late)] & (1 << inpkt->seqno % 8))) {
+			if((n->received_seqno >= sizeof n->late * 8 && inpkt->seqno <= n->received_seqno - sizeof n->late * 8) || !(n->late[(inpkt->seqno / 8) % sizeof n->late] & (1 << inpkt->seqno % 8))) {
 				logger(LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d",
 					   n->name, n->hostname, inpkt->seqno, n->received_seqno);
 				return;
 			}
 		} else {
 			for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
-				n->late[(i / 8) % sizeof(n->late)] |= 1 << i % 8;
+				n->late[(i / 8) % sizeof n->late] |= 1 << i % 8;
 		}
 	}
 	
-	n->late[(inpkt->seqno / 8) % sizeof(n->late)] &= ~(1 << inpkt->seqno % 8);
+	n->late[(inpkt->seqno / 8) % sizeof n->late] &= ~(1 << inpkt->seqno % 8);
 
 	if(inpkt->seqno > n->received_seqno)
 		n->received_seqno = inpkt->seqno;
 			
 	if(n->received_seqno > MAX_SEQNO)
-		keyexpires = 0;
+		regenerate_key();
 
 	/* Decompress the packet */
 
@@ -348,8 +356,10 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	int nextpkt = 0;
 	vpn_packet_t *outpkt;
 	int origlen;
-	int outlen, outpad;
+	size_t outlen;
+#if defined(SOL_IP) && defined(IP_TOS)
 	static int priority = 0;
+#endif
 	int origpriority;
 	int sock;
 
@@ -361,14 +371,16 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	/* Make sure we have a valid key */
 
 	if(!n->status.validkey) {
+		time_t now = time(NULL);
+
 		ifdebug(TRAFFIC) logger(LOG_INFO,
 				   "No valid key known yet for %s (%s), forwarding via TCP",
 				   n->name, n->hostname);
 
-		if(!n->status.waitingforkey)
+		if(n->last_req_key + 10 < now) {
 			send_req_key(n);
-
-		n->status.waitingforkey = true;
+			n->last_req_key = now;
+		}
 
 		send_tcppacket(n->nexthop->connection, origpkt);
 
@@ -408,32 +420,28 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	/* Add sequence number */
 
 	inpkt->seqno = htonl(++(n->sent_seqno));
-	inpkt->len += sizeof(inpkt->seqno);
+	inpkt->len += sizeof inpkt->seqno;
 
 	/* Encrypt the packet */
 
-	if(n->outcipher) {
+	if(cipher_active(&n->outcipher)) {
 		outpkt = pkt[nextpkt++];
+		outlen = MAXSIZE;
 
-		if(!EVP_EncryptInit_ex(&n->outctx, NULL, NULL, NULL, NULL)
-				|| !EVP_EncryptUpdate(&n->outctx, (unsigned char *) &outpkt->seqno, &outlen,
-					(unsigned char *) &inpkt->seqno, inpkt->len)
-				|| !EVP_EncryptFinal_ex(&n->outctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) {
-			ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s): %s",
-						n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
+		if(!cipher_encrypt(&n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
+			ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname);
 			goto end;
 		}
 
-		outpkt->len = outlen + outpad;
+		outpkt->len = outlen;
 		inpkt = outpkt;
 	}
 
 	/* Add the message authentication code */
 
-	if(n->outdigest && n->outmaclength) {
-		HMAC(n->outdigest, n->outkey, n->outkeylength, (unsigned char *) &inpkt->seqno,
-			 inpkt->len, (unsigned char *) &inpkt->seqno + inpkt->len, NULL);
-		inpkt->len += n->outmaclength;
+	if(digest_active(&n->outdigest)) {
+		digest_create(&n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len);
+		inpkt->len += digest_length(&n->outdigest);
 	}
 
 	/* Determine which socket we have to use */
@@ -452,13 +460,13 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	   && listen_socket[sock].sa.sa.sa_family == AF_INET) {
 		priority = origpriority;
 		ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting outgoing packet priority to %d", priority);
-		if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority)))	/* SO_PRIORITY doesn't seem to work */
+		if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof priority))	/* SO_PRIORITY doesn't seem to work */
 			logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
 	}
 #endif
 
-	if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) {
-		if(sockerrno == EMSGSIZE) {
+	if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa)) < 0 && !sockwouldblock(sockerrno)) {
+		if(sockmsgsize(sockerrno)) {
 			if(n->maxmtu >= origlen)
 				n->maxmtu = origlen - 1;
 			if(n->mtu >= origlen)
@@ -509,7 +517,7 @@ void send_packet(const node_t *n, vpn_packet_t *packet) {
 /* Broadcast a packet using the minimum spanning tree */
 
 void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
-	avl_node_t *node;
+	splay_node_t *node;
 	connection_t *c;
 
 	ifdebug(TRAFFIC) logger(LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)",
@@ -533,48 +541,49 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
 }
 
 static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
-	avl_node_t *node;
-	edge_t *e;
-	node_t *n = NULL;
+	splay_node_t *node;
+	node_t *n, *found = NULL;
 	static time_t last_hard_try = 0;
+	time_t now = time(NULL);
 
-	for(node = edge_weight_tree->head; node; node = node->next) {
-		e = node->data;
-
-		if(sockaddrcmp_noport(from, &e->address)) {
-			if(last_hard_try == now)
-				continue;
-			last_hard_try = now;
-		}
+	if(last_hard_try == now)
+		return NULL;
+	else
+		last_hard_try = now;
 
-		if(!n)
-			n = e->to;
+	for(node = node_tree->head; node; node = node->next) {
+		n = node->data;
 
-		if(!try_mac(e->to, pkt))
+		if(n == myself || !n->status.reachable || !digest_active(&n->indigest))
 			continue;
 
-		n = e->to;
-		break;
+		if(try_mac(n, pkt)) {
+			found = n;
+			break;
+		}
 	}
 
-	return n;
+	return found;
 }
 
-void handle_incoming_vpn_data(int sock) {
+void handle_incoming_vpn_data(int sock, short events, void *data) {
 	vpn_packet_t pkt;
 	char *hostname;
 	sockaddr_t from;
-	socklen_t fromlen = sizeof(from);
+	socklen_t fromlen = sizeof from;
 	node_t *n;
+	int len;
 
-	pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
+	len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 
-	if(pkt.len < 0) {
-		if(sockerrno != EAGAIN && sockerrno != EINTR)
+	if(len <= 0 || len > MAXSIZE) {
+		if(!sockwouldblock(sockerrno))
 			logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
 		return;
 	}
 
+	pkt.len = len;
+
 	sockaddrunmap(&from);		/* Some braindead IPv6 implementations do stupid things. */
 
 	n = lookup_node_udp(&from);
@@ -595,3 +604,10 @@ void handle_incoming_vpn_data(int sock) {
 
 	receive_udppacket(n, &pkt);
 }
+
+void handle_device_data(int sock, short events, void *data) {
+	vpn_packet_t packet;
+
+	if(read_packet(&packet))
+		route(myself, &packet);
+}