along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: net_packet.c,v 1.1.2.42 2003/10/10 16:24:24 guus Exp $
+ $Id: net_packet.c,v 1.1.2.49 2003/12/27 16:32:52 guus Exp $
*/
#include "system.h"
-#include <openssl/rand.h>
-#include <openssl/evp.h>
-#include <openssl/pem.h>
-#include <openssl/hmac.h>
+#include <gcrypt.h>
#include <zlib.h>
#include <lzo1x.h>
#include "conf.h"
#include "connection.h"
#include "device.h"
+#include "ethernet.h"
#include "event.h"
#include "graph.h"
#include "list.h"
#include "utils.h"
#include "xalloc.h"
+#ifdef WSAEMSGSIZE
+#define EMSGSIZE WSAEMSGSIZE
+#endif
+
int keylifetime = 0;
int keyexpires = 0;
-EVP_CIPHER_CTX packet_ctx;
static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
+static void send_udppacket(node_t *, vpn_packet_t *);
#define MAX_SEQNO 1073741824
+void send_mtu_probe(node_t *n)
+{
+ vpn_packet_t packet;
+ int len, i;
+
+ cp();
+
+ n->mtuprobes++;
+ n->mtuevent = NULL;
+
+ if(n->mtuprobes >= 10 && !n->minmtu) {
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("No response to MTU probes from %s (%s)"), n->name, n->hostname);
+ return;
+ }
+
+ for(i = 0; i < 3; i++) {
+ if(n->mtuprobes >= 30 || n->minmtu >= n->maxmtu) {
+ n->mtu = n->minmtu;
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("Fixing MTU of %s (%s) to %d after %d probes"), n->name, n->hostname, n->mtu, n->mtuprobes);
+ return;
+ }
+
+ len = n->minmtu + 1 + random() % (n->maxmtu - n->minmtu);
+ if(len < 64)
+ len = 64;
+
+ memset(packet.data, 0, 14);
+ gcry_randomize(packet.data + 14, len - 14, GCRY_WEAK_RANDOM);
+ packet.len = len;
+
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("Sending MTU probe length %d to %s (%s)"), len, n->name, n->hostname);
+
+ send_udppacket(n, &packet);
+ }
+
+ n->mtuevent = xmalloc(sizeof(*n->mtuevent));
+ n->mtuevent->handler = (event_handler_t)send_mtu_probe;
+ n->mtuevent->data = n;
+ n->mtuevent->time = now + 1;
+ event_add(n->mtuevent);
+}
+
+void mtu_probe_h(node_t *n, vpn_packet_t *packet) {
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("Got MTU probe length %d from %s (%s)"), packet->len, n->name, n->hostname);
+
+ if(!packet->data[0]) {
+ packet->data[0] = 1;
+ send_packet(n, packet);
+ } else {
+ if(n->minmtu < packet->len)
+ n->minmtu = packet->len;
+ }
+}
+
static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level)
{
if(level == 10) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"),
packet->len, n->name, n->hostname);
- route_incoming(n, packet);
+ route(n, packet);
}
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;
- char hmac[EVP_MAX_MD_SIZE];
- int i, result;
+ char *hmac = NULL;
+ int result;
+ int i;
+ static char iv[32] = {0};
cp();
if(myself->digest && myself->maclength) {
inpkt->len -= myself->maclength;
- HMAC(myself->digest, myself->key, myself->keylength,
- (char *) &inpkt->seqno, inpkt->len, hmac, NULL);
-
- if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) {
+ gcry_md_reset(myself->digest_ctx);
+ gcry_md_write(myself->digest_ctx, (char *)&inpkt->seqno, inpkt->len);
+ hmac = gcry_md_read(myself->digest_ctx, 0);
+
+ if(!hmac || memcmp(hmac, (char *)&inpkt->seqno + inpkt->len, myself->maclength)) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"),
n->name, n->hostname);
return;
/* Decrypt the packet */
if(myself->cipher) {
- outpkt = pkt[nextpkt++];
+ gcry_cipher_reset(myself->cipher_ctx);
+ //memcpy(iv, &inpkt->seqno, sizeof inpkt->seqno);
+ //gcry_cipher_setiv(myself->cipher_ctx, iv, myself->cipherblklen);
+ result = gcry_cipher_decrypt(myself->cipher_ctx, (char *)&inpkt->seqno, inpkt->len, NULL, 0);
- EVP_DecryptInit_ex(&packet_ctx, NULL, NULL, NULL, NULL);
- if(!EVP_DecryptUpdate(&packet_ctx, (char *) &outpkt->seqno, &outlen,
- (char *) &inpkt->seqno, inpkt->len)) {
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Error decrypting packet from %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
- return;
- }
- if(!EVP_DecryptFinal_ex(&packet_ctx, (char *) &outpkt->seqno + outlen, &outpad)) {
+ if(result) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Error decrypting packet from %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
+ n->name, n->hostname, gpg_strerror(result));
+ logger(LOG_DEBUG, "%p %p %d", myself->cipher_ctx, (char *)&inpkt->seqno, inpkt->len);
return;
}
+ }
+
+ /* Remove padding */
+
+ if(myself->cipherblklen > 1) {
+ int padlen;
- outpkt->len = outlen + outpad;
- inpkt = outpkt;
+ padlen = ((uint8_t *)&inpkt->seqno)[inpkt->len - 1];
+
+ if(padlen && padlen <= myself->cipherblklen)
+ inpkt->len -= padlen;
}
/* Check the sequence number */
if(inpkt->seqno != n->received_seqno + 1) {
if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) {
- logger(LOG_WARNING, _("Lost %d packets from %s (%s)"),
+ logger(LOG_WARNING, _("Lost %u packets from %s (%s)"),
inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
memset(n->late, 0, sizeof(n->late));
} else if (inpkt->seqno <= n->received_seqno) {
if(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"),
+ logger(LOG_WARNING, _("Got late or replayed packet from %s (%s), seqno %u, last received %u"),
n->name, n->hostname, inpkt->seqno, n->received_seqno);
} else
for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
}
}
- n->received_seqno = inpkt->seqno;
- n->late[(n->received_seqno / 8) % sizeof(n->late)] &= ~(1 << n->received_seqno % 8);
+ if(inpkt->seqno > n->received_seqno) {
+ n->received_seqno = inpkt->seqno;
+ n->late[(n->received_seqno / 8) % sizeof(n->late)] &= ~(1 << n->received_seqno % 8);
+ }
if(n->received_seqno > MAX_SEQNO)
keyexpires = 0;
if(n->connection)
n->connection->last_ping_time = now;
- receive_packet(n, inpkt);
+ if(!inpkt->data[12] && !inpkt->data[13])
+ mtu_probe_h(n, inpkt);
+ else
+ receive_packet(n, inpkt);
}
void receive_tcppacket(connection_t *c, char *buffer, int len)
int nextpkt = 0;
vpn_packet_t *outpkt;
int origlen;
- int outlen, outpad;
+ int result;
vpn_packet_t *copy;
static int priority = 0;
int origpriority;
int sock;
+ char *hmac = NULL;
+ static char iv[32] = {0};
cp();
/* Since packet is on the stack of handle_tap_input(), we have to make a copy of it first. */
- copy = xmalloc(sizeof(vpn_packet_t));
- memcpy(copy, inpkt, sizeof(vpn_packet_t));
+ *(copy = xmalloc(sizeof(*copy))) = *inpkt;
list_insert_tail(n->queue, copy);
/* Encrypt the packet */
if(n->cipher) {
- outpkt = pkt[nextpkt++];
-
- EVP_EncryptInit_ex(&n->packet_ctx, NULL, NULL, NULL, NULL);
- if(!EVP_EncryptUpdate(&n->packet_ctx, (char *) &outpkt->seqno, &outlen,
- (char *) &inpkt->seqno, inpkt->len)) {
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while encrypting packet to %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
- return;
+ /* Add padding */
+
+ if(n->cipherblklen > 1) {
+ int padlen, i;
+ uint8_t *p;
+
+ padlen = n->cipherblklen - inpkt->len % n->cipherblklen;
+ p = (char *)&inpkt->seqno + inpkt->len;
+
+ if(padlen == n->cipherblklen) {
+ if(p[-1] != 0 && p[-1] <= n->cipherblklen) {
+ inpkt->len += n->cipherblklen;
+ for(i = 0; i < n->cipherblklen; i++)
+ *p++ = i + 1;
+ }
+ } else {
+ inpkt->len += padlen;
+ for(i = 0; i < padlen; i++)
+ *p++ = i + 1;
+ }
}
- if(!EVP_EncryptFinal_ex(&n->packet_ctx, (char *) &outpkt->seqno + outlen, &outpad)) {
+
+ gcry_cipher_reset(n->cipher_ctx);
+ //memcpy(iv, &inpkt->seqno, sizeof inpkt->seqno);
+ //gcry_cipher_setiv(n->cipher_ctx, iv, n->cipherblklen);
+ result = gcry_cipher_encrypt(n->cipher_ctx, (char *)&inpkt->seqno, inpkt->len, NULL, 0);
+
+ if(result) {
ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while encrypting packet to %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
- return;
+ n->name, n->hostname, gpg_strerror(result));
+ goto end;
}
-
- outpkt->len = outlen + outpad;
- inpkt = outpkt;
}
/* Add the message authentication code */
if(n->digest && n->maclength) {
- HMAC(n->digest, n->key, n->keylength, (char *) &inpkt->seqno,
- inpkt->len, (char *) &inpkt->seqno + inpkt->len, &outlen);
+ gcry_md_reset(n->digest_ctx);
+ gcry_md_write(n->digest_ctx, (char *)&inpkt->seqno, inpkt->len);
+ hmac = gcry_md_read(n->digest_ctx, 0);
+
+ if(!hmac) {
+ ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while authenticating packet to %s (%s)"),
+ n->name, n->hostname);
+ goto end;
+ }
+
+ memcpy((char *)&inpkt->seqno + inpkt->len, hmac, n->maclength);
inpkt->len += n->maclength;
}
#endif
if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) {
- logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, n->hostname, strerror(errno));
- return;
+ if(errno == EMSGSIZE) {
+ if(n->maxmtu >= origlen)
+ n->maxmtu = origlen - 1;
+ if(n->mtu >= origlen)
+ n->mtu = origlen - 1;
+ } else
+ logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, n->hostname, strerror(errno));
}
+end:
inpkt->len = origlen;
}
cp();
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"),
- packet->len, n->name, n->hostname);
-
if(n == myself) {
- ifdebug(TRAFFIC) logger(LOG_NOTICE, _("Packet is looping back to us!"));
+ if(overwrite_mac)
+ memcpy(packet->data, mymac.x, ETH_ALEN);
+ write_packet(packet);
return;
}
+ ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"),
+ packet->len, n->name, n->hostname);
+
if(!n->status.reachable) {
ifdebug(TRAFFIC) logger(LOG_INFO, _("Node %s (%s) is not reachable"),
n->name, n->hostname);