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- Small fixes

Browse source 
- Do proper key exchange
- Encrypt packets - it works, but there is something wrong with the MAC
  header after decryption...
This commit is contained in:
Guus Sliepen 2000-10-29 10:39:08 +00:00
parent 8fa9bc017d
commit cea3d8f305
2 changed files with 87 additions and 47 deletions
Download patch file Download diff file Expand all files Collapse all files

75
src/net.c
View file

@ -17,7 +17,7 @@
along with this program; if not, write to the Free Software along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: net.c,v 1.35.4.53 2000/10/29 09:19:24 guus Exp $ $Id: net.c,v 1.35.4.54 2000/10/29 10:39:06 guus Exp $
*/ */
#include "config.h" #include "config.h"
@ -39,6 +39,9 @@
#include <syslog.h> #include <syslog.h>
#include <unistd.h> #include <unistd.h>
#include <sys/ioctl.h> #include <sys/ioctl.h>
#include <openssl/rand.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#ifdef HAVE_TUNTAP #ifdef HAVE_TUNTAP
#include LINUX_IF_TUN_H #include LINUX_IF_TUN_H
@ -67,6 +70,9 @@ int total_socket_out = 0;
config_t *upstreamcfg; config_t *upstreamcfg;
static int seconds_till_retry; static int seconds_till_retry;
int keylifetime = 0;
int keyexpires = 0;
char *unknown = NULL; char *unknown = NULL;
subnet_t mymac; subnet_t mymac;
@ -101,19 +107,20 @@ int xsend(conn_list_t *cl, vpn_packet_t *inpkt)
{ {
vpn_packet_t outpkt; vpn_packet_t outpkt;
int outlen, outpad; int outlen, outpad;
EVP_CIPHER_CTX ctx;
cp cp
outpkt.len = inpkt->len; outpkt.len = inpkt->len;
/*
EVP_EncryptInit(cl->cipher_pktctx, cl->cipher_pkttype, cl->cipher_pktkey, NULL); EVP_EncryptInit(&ctx, cl->cipher_pkttype, cl->cipher_pktkey, cl->cipher_pktkey);
EVP_EncryptUpdate(cl->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); EVP_EncryptUpdate(&ctx, outpkt.data, &outlen, inpkt->data, inpkt->len);
EVP_EncryptFinal(cl->cipher_pktctx, outpkt.data + outlen, &outpad); EVP_EncryptFinal(&ctx, outpkt.data + outlen, &outpad);
outlen += outpad + 2; outlen += outpad + 2;
Do encryption when everything else is fixed... /* Bypass
*/
outlen = outpkt.len + 2; outlen = outpkt.len + 2;
memcpy(&outpkt, inpkt, outlen); memcpy(&outpkt, inpkt, outlen);
*/
if(debug_lvl >= DEBUG_TRAFFIC) if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"),
outlen, cl->name, cl->hostname); outlen, cl->name, cl->hostname);
@ -136,18 +143,18 @@ int xrecv(vpn_packet_t *inpkt)
{ {
vpn_packet_t outpkt; vpn_packet_t outpkt;
int outlen, outpad; int outlen, outpad;
EVP_CIPHER_CTX ctx;
cp cp
outpkt.len = inpkt->len; outpkt.len = inpkt->len;
/* EVP_DecryptInit(&ctx, myself->cipher_pkttype, myself->cipher_pktkey, NULL);
EVP_DecryptInit(myself->cipher_pktctx, myself->cipher_pkttype, myself->cipher_pktkey, NULL); EVP_DecryptUpdate(&ctx, outpkt.data, &outlen, inpkt->data, inpkt->len);
EVP_DecryptUpdate(myself->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); EVP_DecryptFinal(&ctx, outpkt.data + outlen, &outpad);
EVP_DecryptFinal(myself->cipher_pktctx, outpkt.data + outlen, &outpad);
outlen += outpad; outlen += outpad;
Do decryption is everything else is fixed... /* Bypass
*/
outlen = outpkt.len+2; outlen = outpkt.len+2;
memcpy(&outpkt, inpkt, outlen); memcpy(&outpkt, inpkt, outlen);
*/
/* Fix mac address */ /* Fix mac address */
@ -329,7 +336,7 @@ cp
if(!cl->status.validkey) if(!cl->status.validkey)
{ {
/* Don't queue until everything else is fixed. /* FIXME: Don't queue until everything else is fixed.
if(debug_lvl >= DEBUG_TRAFFIC) if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"), syslog(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"),
cl->name, cl->hostname); cl->name, cl->hostname);
@ -342,7 +349,7 @@ cp
if(!cl->status.active) if(!cl->status.active)
{ {
/* Don't queue until everything else is fixed. /* FIXME: Don't queue until everything else is fixed.
if(debug_lvl >= DEBUG_TRAFFIC) if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("%s (%s) is not ready, queueing packet"), syslog(LOG_INFO, _("%s (%s) is not ready, queueing packet"),
cl->name, cl->hostname); cl->name, cl->hostname);
@ -761,6 +768,22 @@ cp
return -1; return -1;
} }
/* Generate packet encryption key */
myself->cipher_pkttype = EVP_bf_cbc();
myself->cipher_pktkey = (char *)xmalloc(64);
RAND_bytes(myself->cipher_pktkey, 64);
if(!(cfg = get_config_val(config, keyexpire)))
keylifetime = 3600;
else
keylifetime = cfg->data.val;
keyexpires = time(NULL) + keylifetime;
/* Activate ourselves */
myself->status.active = 1; myself->status.active = 1;
syslog(LOG_NOTICE, _("Ready: listening on port %hd"), myself->port); syslog(LOG_NOTICE, _("Ready: listening on port %hd"), myself->port);
@ -1281,6 +1304,7 @@ void main_loop(void)
struct timeval tv; struct timeval tv;
int r; int r;
time_t last_ping_check; time_t last_ping_check;
int t;
cp cp
last_ping_check = time(NULL); last_ping_check = time(NULL);
@ -1322,11 +1346,26 @@ cp
continue; continue;
} }
if(last_ping_check + timeout < time(NULL)) t = time(NULL);
/* Let's check if everybody is still alive */
/* Let's check if everybody is still alive */
if(last_ping_check + timeout < t)
{ {
check_dead_connections(); check_dead_connections();
last_ping_check = time(NULL); last_ping_check = time(NULL);
/* Should we regenerate our key? */
if(keyexpires < t)
{
if(debug_lvl >= DEBUG_STATUS)
syslog(LOG_INFO, _("Regenerating symmetric key"));
RAND_bytes(myself->cipher_pktkey, 64);
send_key_changed(myself, NULL);
keyexpires = time(NULL) + keylifetime;
}
} }
if(r > 0) if(r > 0)

59
src/protocol.c
View file

@ -17,7 +17,7 @@
along with this program; if not, write to the Free Software along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: protocol.c,v 1.28.4.50 2000/10/29 09:19:25 guus Exp $ $Id: protocol.c,v 1.28.4.51 2000/10/29 10:39:08 guus Exp $
*/ */
#include "config.h" #include "config.h"
@ -38,6 +38,7 @@
#include <openssl/sha.h> #include <openssl/sha.h>
#include <openssl/rand.h> #include <openssl/rand.h>
#include <openssl/evp.h>
#include "conf.h" #include "conf.h"
#include "net.h" #include "net.h"
@ -470,6 +471,7 @@ cp
cl->allow_request = ALL; cl->allow_request = ALL;
cl->status.active = 1; cl->status.active = 1;
cl->nexthop = cl; cl->nexthop = cl;
cl->cipher_pkttype = EVP_bf_cbc();
if(debug_lvl >= DEBUG_CONNECTIONS) if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname); syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);
@ -992,6 +994,7 @@ int req_key_h(conn_list_t *cl)
{ {
char *from_id, *to_id; char *from_id, *to_id;
conn_list_t *from, *to; conn_list_t *from, *to;
char pktkey[129];
cp cp
if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2) if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2)
{ {
@ -1012,7 +1015,9 @@ cp
if(!strcmp(to_id, myself->name)) if(!strcmp(to_id, myself->name))
{ {
send_ans_key(myself, from, myself->cipher_pktkey); bin2hex(myself->cipher_pktkey, pktkey, 64);
pktkey[128] = 0;
send_ans_key(myself, from, pktkey);
} }
else else
{ {
@ -1059,46 +1064,42 @@ cp
return -1; return -1;
} }
/* Check if this key request is for us */ /* Update origin's packet key */
if(!strcmp(to_id, myself->name)) keylength = strlen(pktkey);
if((keylength%2)!=0 || (keylength <= 0))
{ {
/* It is for us, convert it to binary and set the key with it. */ syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"),
cl->name, cl->hostname, from->name);
keylength = strlen(pktkey); free(from_id); free(to_id); free(pktkey);
return -1;
if((keylength%2)!=0 || (keylength <= 0))
{
syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"),
cl->name, cl->hostname, from->name);
free(from_id); free(to_id); free(pktkey);
return -1;
}
if(from->cipher_pktkey)
free(from->cipher_pktkey);
keylength /= 2;
hex2bin(pktkey, pktkey, keylength);
pktkey[keylength] = '\0';
from->cipher_pktkey = pktkey;
from->status.validkey = 1;
from->status.waitingforkey = 0;
} }
else
if(from->cipher_pktkey)
free(from->cipher_pktkey);
keylength /= 2;
hex2bin(pktkey, pktkey, keylength);
pktkey[keylength] = '\0';
from->cipher_pktkey = pktkey;
from->status.validkey = 1;
from->status.waitingforkey = 0;
if(strcmp(to_id, myself->name))
{ {
if(!(to = lookup_id(to_id))) if(!(to = lookup_id(to_id)))
{ {
syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"), syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"),
cl->name, cl->hostname, to_id); cl->name, cl->hostname, to_id);
free(from_id); free(to_id); free(pktkey); free(from_id); free(to_id);
return -1; return -1;
} }
send_ans_key(from, to, pktkey); send_ans_key(from, to, pktkey);
} }
free(from_id); free(to_id); free(pktkey); free(from_id); free(to_id);
cp cp
return 0; return 0;
} }