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control.c
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control.c
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/*
* Layer Two Tunnelling Protocol Daemon
* Copyright (C) 1998 Adtran, Inc.
* Copyright (C) 2002 Jeff McAdams
*
* Mark Spencer
*
* This software is distributed under the terms
* of the GPL, which you should have received
* along with this source.
*
* Control Packet Handling
*
*/
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include "l2tp.h"
_u16 ppp_crc16_table[256] = {
0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};
int global_serno = 1;
struct buffer *new_outgoing (struct tunnel *t)
{
/*
* Make a new outgoing control packet
*/
struct buffer *tmp = new_buf (MAX_RECV_SIZE);
if (!tmp)
return NULL;
tmp->peer = t->peer;
tmp->start += sizeof (struct control_hdr);
tmp->len = 0;
tmp->retries = 0;
tmp->tunnel = t;
return tmp;
}
inline void recycle_outgoing (struct buffer *buf, struct sockaddr_in peer)
{
/*
* This should only be used for ZLB's!
*/
buf->start = buf->rstart + sizeof (struct control_hdr);
buf->peer = peer;
buf->len = 0;
buf->retries = -1;
buf->tunnel = NULL;
}
void add_fcs (struct buffer *buf)
{
_u16 fcs = PPP_INITFCS;
unsigned char *c = buf->start;
size_t x;
for (x = 0; x < buf->len; x++)
{
fcs = PPP_FCS (fcs, *c);
c++;
}
fcs = fcs ^ 0xFFFF;
*c = fcs & 0xFF;
c++;
*c = (fcs >> 8) & 0xFF;
buf->len += 2;
}
void add_control_hdr (struct tunnel *t, struct call *c, struct buffer *buf)
{
struct control_hdr *h;
buf->start -= sizeof (struct control_hdr);
buf->len += sizeof (struct control_hdr);
h = (struct control_hdr *) buf->start;
h->ver = htons (TBIT | LBIT | FBIT | VER_L2TP);
h->length = htons ((_u16) buf->len);
h->tid = htons (t->tid);
h->cid = htons (c->cid);
h->Ns = htons (t->control_seq_num);
h->Nr = htons (t->control_rec_seq_num);
t->control_seq_num++;
}
void hello (void *tun)
{
struct buffer *buf;
struct tunnel *t;
struct timeval tv;
tv.tv_sec = HELLO_DELAY;
tv.tv_usec = 0;
t = (struct tunnel *) tun;
buf = new_outgoing (t);
add_message_type_avp (buf, Hello);
add_control_hdr (t, t->self, buf);
if (gconfig.packet_dump)
do_packet_dump (buf);
#ifdef DEBUG_HELLO
l2tp_log (LOG_DEBUG, "%s: sending Hello on %d\n", __FUNCTION__, t->ourtid);
#endif
control_xmit (buf);
/*
* Schedule another Hello in a little bit.
*/
#ifdef DEBUG_HELLO
l2tp_log (LOG_DEBUG, "%s: scheduling another Hello on %d\n", __FUNCTION__,
t->ourtid);
#endif
t->hello = schedule (tv, hello, (void *) t);
}
void control_zlb (struct buffer *buf, struct tunnel *t, struct call *c)
{
recycle_outgoing (buf, t->peer);
add_control_hdr (t, c, buf);
t->control_seq_num--;
#ifdef DEBUG_ZLB
l2tp_log (LOG_DEBUG, "%s: sending control ZLB on tunnel %d\n", __FUNCTION__,
t->tid);
#endif
udp_xmit (buf, t);
}
/*
* Get a local address from the local range, if configured.
*/
static int get_local_addr(struct tunnel *t, struct call *c)
{
#ifdef IP_ALLOCATION
if (t->lns->localrange) {
c->lns->localaddr = get_addr (t->lns->localrange);
if (!c->lns->localaddr)
{
set_error (c, ERROR_NORES, "No available local IP addresses");
call_close (c);
l2tp_log (LOG_DEBUG, "%s: Out of local IP addresses on tunnel %d!\n",
__FUNCTION__, t->tid);
return -EINVAL;
}
reserve_addr (c->lns->localaddr);
}
#endif
return 0;
}
int control_finish (struct tunnel *t, struct call *c)
{
/*
* After all AVP's have been handled, do anything else
* which needs to be done, like prepare response
* packets to go back. This is essentially the
* implementation of the state machine of section 7.2.1
*
* If we set c->needclose, the call (or tunnel) will
* be closed upon return.
*/
struct buffer *buf;
struct call *p, *z;
struct tunnel *y;
struct timeval tv;
struct ppp_opts *po;
char ip1[STRLEN];
char ip2[STRLEN];
char dummy_buf[128] = "/var/l2tp/"; /* jz: needed to read /etc/ppp/var.options - just kick it if you don't like */
char passwdfd_buf[32] = ""; /* buffer for the fd, not the password */
int i;
int pppd_passwdfd[2];
int tmptid,tmpcid;
if (c->msgtype < 0)
{
l2tp_log (LOG_DEBUG, "%s: Whoa... non-ZLB with no message type!\n",
__FUNCTION__);
return -EINVAL;
}
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG,
"%s: message type is %s(%d). Tunnel is %d, call is %d.\n",
__FUNCTION__, msgtypes[c->msgtype], c->msgtype, t->tid, c->cid);
switch (c->msgtype)
{
case 0:
/*
* We need to initiate a connection.
*/
if (t->self == c)
{
if (t->lns)
{
t->ourrws = t->lns->tun_rws;
t->hbit = t->lns->hbit;
t->rxspeed = t->lns->rxspeed;
t->txspeed = t->lns->txspeed;
}
else if (t->lac)
{
t->ourrws = t->lac->tun_rws;
t->hbit = t->lac->hbit;
t->rxspeed = t->lac->rxspeed;
t->txspeed = t->lac->txspeed;
}
/* This is an attempt to bring up the tunnel */
t->state = SCCRQ;
buf = new_outgoing (t);
add_message_type_avp (buf, SCCRQ);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
add_protocol_avp (buf);
add_frame_caps_avp (buf, t->ourfc);
add_bearer_caps_avp (buf, t->ourbc);
/* FIXME: Tie breaker */
add_firmware_avp (buf);
if (t->lac && t->lac->hostname && t->lac->hostname[0])
add_hostname_avp (buf, t->lac->hostname);
else if (t->lns && t->lns->hostname && t->lns->hostname[0])
add_hostname_avp (buf, t->lns->hostname);
else
add_hostname_avp (buf, hostname);
add_vendor_avp (buf);
add_tunnelid_avp (buf, t->ourtid);
if (t->ourrws >= 0)
add_avp_rws (buf, t->ourrws);
if ((t->lac && t->lac->challenge)
|| (t->lns && t->lns->challenge))
{
if (t->chal_them.challenge)
free(t->chal_them.challenge);
t->chal_them.challenge = malloc(MD_SIG_SIZE);
if (!(t->chal_them.challenge))
{
l2tp_log (LOG_WARNING, "%s: malloc failed for challenge\n",
__FUNCTION__);
toss (buf);
return -EINVAL;
}
mk_challenge (t->chal_them.challenge, MD_SIG_SIZE);
t->chal_them.chal_len = MD_SIG_SIZE;
add_challenge_avp (buf, t->chal_them.challenge,
t->chal_them.chal_len);
t->chal_them.state = STATE_CHALLENGED;
/* We generate the challenge and make a note that we plan to
challenge the peer, but we can't predict the response yet
because we don't know their hostname AVP */
}
add_control_hdr (t, c, buf);
c->cnu = 0;
if (gconfig.packet_dump)
do_packet_dump (buf);
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: sending SCCRQ\n",
__FUNCTION__);
control_xmit (buf);
}
else
{
if (switch_io)
{
c->state = ICRQ;
if (c->lns)
{
c->lbit = c->lns->lbit ? LBIT : 0;
/* c->ourrws = c->lns->call_rws;
if (c->ourrws > -1) c->ourfbit = FBIT; else c->ourfbit = 0; */
}
else if (c->lac)
{
c->lbit = c->lac->lbit ? LBIT : 0;
/* c->ourrws = c->lac->call_rws;
if (c->ourrws > -1) c->ourfbit = FBIT; else c->ourfbit = 0; */
}
buf = new_outgoing (t);
add_message_type_avp (buf, ICRQ);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
#ifdef TEST_HIDDEN
add_callid_avp (buf, c->ourcid, t);
#else
add_callid_avp (buf, c->ourcid);
#endif
add_serno_avp (buf, global_serno);
c->serno = global_serno;
global_serno++;
add_bearer_avp (buf, 0);
add_control_hdr (t, c, buf);
c->cnu = 0;
if (gconfig.packet_dump)
do_packet_dump (buf);
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: sending ICRQ\n", __FUNCTION__);
control_xmit (buf);
}
else
{ /* jz: sending a OCRQ */
c->state = OCRQ;
if (c->lns)
{
c->lbit = c->lns->lbit ? LBIT : 0;
/* c->ourrws = c->lns->call_rws;
if (c->ourrws > -1) c->ourfbit = FBIT; else c->ourfbit = 0; */
}
else if (c->lac)
{
/* c->ourrws = c->lac->call_rws;
if (c->ourrws > -1) c->ourfbit = FBIT; else c->ourfbit = 0; */
}
if (t->fc & SYNC_FRAMING)
c->frame = SYNC_FRAMING;
else
c->frame = ASYNC_FRAMING;
buf = new_outgoing (t);
add_message_type_avp (buf, OCRQ);
#ifdef TEST_HIDDEN
add_callid_avp (buf, c->ourcid, t);
#else
add_callid_avp (buf, c->ourcid);
#endif
add_serno_avp (buf, global_serno);
c->serno = global_serno;
global_serno++;
add_minbps_avp (buf, DEFAULT_MIN_BPS);
add_maxbps_avp (buf, DEFAULT_MAX_BPS);
add_bearer_avp (buf, 0);
add_frame_avp (buf, c->frame);
add_number_avp (buf, c->dial_no);
add_control_hdr (t, c, buf);
c->cnu = 0;
if (gconfig.packet_dump)
do_packet_dump (buf);
control_xmit (buf);
}
}
break;
case SCCRQ:
/*
* We've received a request, now let's
* formulate a response.
*/
if (t->tid <= 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify assigned tunnel ID. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify your assigned tunnel ID");
c->needclose = -1;
return -EINVAL;
}
if (!(t->lns = get_lns (t)))
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Denied connection to unauthorized peer %s\n",
__FUNCTION__, IPADDY (t->peer.sin_addr));
set_error (c, VENDOR_ERROR, "No Authorization");
c->needclose = -1;
return -EINVAL;
}
t->ourrws = t->lns->tun_rws;
t->hbit = t->lns->hbit;
if (t->fc < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify framing capability. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify framing capability");
c->needclose = -1;
return -EINVAL;
}
/* FIXME: Do we need to be sure they specified a version number?
* Theoretically, yes, but we don't have anything in the code
* to actually *do* anything with it, so...why check at this point?
* We shouldn't be requiring a bearer capabilities AVP to be present in
* SCCRQ and SCCRP as they aren't required
if (t->bc < 0 ) {
if (DEBUG) l2tp_log(LOG_DEBUG,
"%s: Peer did not specify bearer capability. Closing.\n",__FUNCTION__);
set_error(c, VENDOR_ERROR, "Specify bearer capability");
c->needclose = -1;
return -EINVAL;
} */
if ((!strlen (t->hostname)) && ((t->chal_us.state) || ((t->lns->challenge))))
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify hostname. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify your hostname");
c->needclose = -1;
return -EINVAL;
}
y = tunnels.head;
while (y)
{
if ((y->tid == t->tid) &&
(y->peer.sin_addr.s_addr == t->peer.sin_addr.s_addr) &&
(!gconfig.ipsecsaref || y->refhim == t->refhim) &&
(y != t))
{
/* This can happen if we get a duplicate
StartCCN or if they don't get our ACK packet */
/*
* But it is legitimate for two different remote systems
* to use the same tid
*/
l2tp_log (LOG_DEBUG,
"%s: Peer requested tunnel %d twice, ignoring second one.\n",
__FUNCTION__, t->tid);
c->needclose = 0;
c->closing = -1;
return 0;
}
y = y->next;
}
t->state = SCCRP;
buf = new_outgoing (t);
add_message_type_avp (buf, SCCRP);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
add_protocol_avp (buf);
add_frame_caps_avp (buf, t->ourfc);
add_bearer_caps_avp (buf, t->ourbc);
add_firmware_avp (buf);
if (t->lac && t->lac->hostname && t->lac->hostname[0])
add_hostname_avp (buf, t->lac->hostname);
else if (t->lns && t->lns->hostname && t->lns->hostname[0])
add_hostname_avp (buf, t->lns->hostname);
else
add_hostname_avp (buf, hostname);
add_vendor_avp (buf);
add_tunnelid_avp (buf, t->ourtid);
if (t->ourrws >= 0)
add_avp_rws (buf, t->ourrws);
if (t->chal_us.state)
{
t->chal_us.ss = SCCRP;
handle_challenge (t, &t->chal_us);
add_chalresp_avp (buf, t->chal_us.response, MD_SIG_SIZE);
}
if (t->lns->challenge)
{
if (t->chal_them.challenge)
free(t->chal_them.challenge);
t->chal_them.challenge = malloc(MD_SIG_SIZE);
if (!(t->chal_them.challenge))
{
l2tp_log (LOG_WARNING, "%s: malloc failed\n", __FUNCTION__);
set_error (c, VENDOR_ERROR, "malloc failed");
toss (buf);
return -EINVAL;
}
mk_challenge (t->chal_them.challenge, MD_SIG_SIZE);
t->chal_them.chal_len = MD_SIG_SIZE;
t->chal_them.ss = SCCCN;
if (handle_challenge (t, &t->chal_them))
{
/* We already know what to expect back */
l2tp_log (LOG_WARNING, "%s: No secret for '%s'\n", __FUNCTION__,
t->hostname);
set_error (c, VENDOR_ERROR, "No secret on our side");
toss (buf);
return -EINVAL;
};
add_challenge_avp (buf, t->chal_them.challenge,
t->chal_them.chal_len);
}
add_control_hdr (t, c, buf);
if (gconfig.packet_dump)
do_packet_dump (buf);
c->cnu = 0;
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: sending SCCRP\n", __FUNCTION__);
control_xmit (buf);
break;
case SCCRP:
/*
* We have a reply. If everything is okay, send
* a connected message
*/
if (t->fc < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify framing capability. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify framing capability");
c->needclose = -1;
return -EINVAL;
}
/* FIXME: Do we need to be sure they specified a version number?
* Theoretically, yes, but we don't have anything in the code
* to actually *do* anything with it, so...why check at this point?
* We shouldn't be requiring a bearer capabilities AVP to be present in
* SCCRQ and SCCRP as they aren't required
if (t->bc < 0 ) {
if (DEBUG) log(LOG_DEBUG,
"%s: Peer did not specify bearer capability. Closing.\n",__FUNCTION__);
set_error(c, VENDOR_ERROR, "Specify bearer capability");
c->needclose = -1;
return -EINVAL;
} */
if ((!strlen (t->hostname)) && ((t->chal_them.state) || ((t->chal_us.state))))
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify hostname. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify your hostname");
c->needclose = -1;
return -EINVAL;
}
if (t->tid <= 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer did not specify assigned tunnel ID. Closing.\n",
__FUNCTION__);
set_error (c, VENDOR_ERROR, "Specify your assigned tunnel ID");
c->needclose = -1;
return -EINVAL;
}
if (t->chal_them.state)
{
t->chal_them.ss = SCCRP;
if (handle_challenge (t, &t->chal_them))
{
set_error (c, VENDOR_ERROR, "No secret key on our side");
l2tp_log (LOG_WARNING, "%s: No secret key for authenticating '%s'\n",
__FUNCTION__, t->hostname);
c->needclose = -1;
return -EINVAL;
}
if (memcmp
(t->chal_them.reply, t->chal_them.response, MD_SIG_SIZE))
{
set_error (c, VENDOR_ERROR,
"Invalid challenge authentication");
l2tp_log (LOG_DEBUG, "%s: Invalid authentication for host '%s'\n",
__FUNCTION__, t->hostname);
c->needclose = -1;
return -EINVAL;
}
}
if (t->chal_us.state)
{
t->chal_us.ss = SCCCN;
if (handle_challenge (t, &t->chal_us))
{
l2tp_log (LOG_WARNING, "%s: No secret for authenticating to '%s'\n",
__FUNCTION__, t->hostname);
set_error (c, VENDOR_ERROR, "No secret key on our end");
c->needclose = -1;
return -EINVAL;
};
}
t->state = SCCCN;
buf = new_outgoing (t);
add_message_type_avp (buf, SCCCN);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
if (t->chal_us.state)
add_chalresp_avp (buf, t->chal_us.response, MD_SIG_SIZE);
add_control_hdr (t, c, buf);
if (gconfig.packet_dump)
do_packet_dump (buf);
c->cnu = 0;
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: sending SCCCN\n", __FUNCTION__);
control_xmit (buf);
#ifdef USE_KERNEL
connect_pppol2tp(t);
#endif
/* Schedule a HELLO */
tv.tv_sec = HELLO_DELAY;
tv.tv_usec = 0;
#ifdef DEBUG_HELLO
l2tp_log (LOG_DEBUG, "%s: scheduling initial HELLO on %d\n", __FUNCTION__,
t->ourtid);
#endif
t->hello = schedule (tv, hello, (void *) t);
l2tp_log (LOG_NOTICE,
"Connection established to %s, %d. Local: %d, Remote: %d (ref=%u/%u).\n",
IPADDY (t->peer.sin_addr),
ntohs (t->peer.sin_port), t->ourtid, t->tid, t->refme, t->refhim);
if (t->lac)
{
/* This is part of a LAC, so we want to go ahead
and start an ICRQ now */
magic_lac_dial (t->lac);
}
break;
case SCCCN:
if (t->chal_them.state)
{
if (memcmp
(t->chal_them.reply, t->chal_them.response, MD_SIG_SIZE))
{
set_error (c, VENDOR_ERROR,
"Invalid challenge authentication");
l2tp_log (LOG_DEBUG, "%s: Invalid authentication for host '%s'\n",
__FUNCTION__, t->hostname);
c->needclose = -1;
return -EINVAL;
}
}
t->state = SCCCN;
l2tp_log (LOG_NOTICE,
"Connection established to %s, %d. Local: %d, Remote: %d (ref=%u/%u). LNS session is '%s'\n",
IPADDY (t->peer.sin_addr),
ntohs (t->peer.sin_port), t->ourtid, t->tid, t->refme, t->refhim,
t->lns->entname);
#ifdef USE_KERNEL
connect_pppol2tp(t);
#endif
/* Schedule a HELLO */
tv.tv_sec = HELLO_DELAY;
tv.tv_usec = 0;
#ifdef DEBUG_HELLO
l2tp_log (LOG_DEBUG, "%s: scheduling initial HELLO on %d\n", __FUNCTION__,
t->ourtid);
#endif
t->hello = schedule (tv, hello, (void *) t);
break;
case StopCCN:
if (t->qtid < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer tried to disconnect without specifying tunnel ID\n",
__FUNCTION__);
return -EINVAL;
}
/* Work around bug in MSL2TP client */
if ((t->firmware == 0xff00) && (!(strncmp(t->vendor, "Deterministic Networks Inc.", 27))))
tmptid = t->ourtid;
else
tmptid = t->tid;
if ((t->qtid != tmptid) && (tmptid > 0))
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer [Vendor:%s] [Firmware:%d (0x%.4x)] tried to disconnect with invalid TID (%d != %d)\n",
__FUNCTION__, t->vendor, t->firmware, t->firmware, t->qtid, tmptid);
return -EINVAL;
}
/* In case they're disconnecting immediately after SCCN */
if (!t->tid)
t->tid = t->qtid;
if (t->self->result < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer tried to disconnect without specifying result code.\n",
__FUNCTION__);
return -EINVAL;
}
l2tp_log (LOG_INFO,
"%s: Connection closed to %s, port %d (%s), Local: %d, Remote: %d\n",
__FUNCTION__, IPADDY (t->peer.sin_addr),
ntohs (t->peer.sin_port), t->self->errormsg, t->ourtid, t->tid);
c->needclose = 0;
c->closing = -1;
break;
case ICRQ:
p = t->call_head;
if (!p->lns)
{
set_error (p, ERROR_INVALID, "This tunnel cannot accept calls\n");
call_close (p);
return -EINVAL;
}
p->lbit = p->lns->lbit ? LBIT : 0;
/* p->ourrws = p->lns->call_rws;
if (p->ourrws > -1) p->ourfbit = FBIT; else p->ourfbit = 0; */
if (p->cid < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer tried to initiate call without call ID\n",
__FUNCTION__);
/* Here it doesn't make sense to use the needclose flag because
the call p did not receive any packets */
call_close (p);
return -EINVAL;
}
z = p->next;
while (z)
{
if (z->cid == p->cid)
{
/* This can happen if we get a duplicate
ICRQ or if they don't get our ACK packet */
l2tp_log (LOG_DEBUG,
"%s: Peer requested call %d twice, ignoring second one.\n",
__FUNCTION__, p->cid);
p->needclose = 0;
p->closing = -1;
return 0;
}
z = z->next;
}
p = t->call_head;
/* FIXME: by commenting this out, we're not checking whether the serial
* number avp is included in the ICRQ at all which its required to be.
* Since the serial number is only used for human debugging aid, this
* isn't a big deal, but it would be nice to have *some* sort of check
* for it and perhaps just log it and go on. */
/* JLM if (p->serno<1) {
if (DEBUG) log(LOG_DEBUG,
"%s: Peer did not specify serial number when initiating call\n", __FUNCTION__);
call_close(p);
return -EINVAL;
} */
#ifdef IP_ALLOCATION
if (t->lns->assign_ip) {
p->addr = get_addr (t->lns->range);
if (!p->addr)
{
set_error (p, ERROR_NORES, "No available IP address");
call_close (p);
l2tp_log (LOG_DEBUG, "%s: Out of IP addresses on tunnel %d!\n",
__FUNCTION__, t->tid);
return -EINVAL;
}
reserve_addr (p->addr);
}
else
p->addr = 0;
#endif
p->state = ICRP;
buf = new_outgoing (t);
add_message_type_avp (buf, ICRP);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
#ifdef TEST_HIDDEN
add_callid_avp (buf, p->ourcid, t);
#else
add_callid_avp (buf, p->ourcid);
#endif
/* if (p->ourrws >=0)
add_avp_rws(buf, p->ourrws); */
/*
* FIXME: I should really calculate
* Packet Processing Delay
*/
/* add_ppd_avp(buf,ppd); */
add_control_hdr (t, p, buf);
if (gconfig.packet_dump)
do_packet_dump (buf);
p->cnu = 0;
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: Sending ICRP\n", __FUNCTION__);
control_xmit (buf);
break;
case ICRP:
if (c->cid < 0)
{
if (DEBUG)
l2tp_log (LOG_DEBUG,
"%s: Peer tried to negotiate ICRP without specifying call ID\n",
__FUNCTION__);
c->needclose = -1;
return -EINVAL;
}
c->state = ICCN;
if (t->fc & SYNC_FRAMING)
c->frame = SYNC_FRAMING;
else
c->frame = ASYNC_FRAMING;
buf = new_outgoing (t);
add_message_type_avp (buf, ICCN);
if (t->hbit)
{
mk_challenge (t->chal_them.vector, VECTOR_SIZE);
add_randvect_avp (buf, t->chal_them.vector, VECTOR_SIZE);
}
add_txspeed_avp (buf, t->txspeed);
add_frame_avp (buf, c->frame);
/* if (c->ourrws >= 0)
add_avp_rws(buf, c->ourrws); */
#ifndef CONFIG_WATCHDOG_FIREWALL
/* FIXME: Packet Processing Delay */
/* We don't need any kind of proxy PPP stuff */
/* Can we proxy authenticate ourselves??? */
add_rxspeed_avp (buf, t->rxspeed);
#endif
/* add_seqreqd_avp (buf); *//* We don't have sequencing code, so
* don't ask for sequencing */
add_control_hdr (t, c, buf);
if (gconfig.packet_dump)
do_packet_dump (buf);
c->cnu = 0;
if (gconfig.debug_state)
l2tp_log (LOG_DEBUG, "%s: Sending ICCN\n", __FUNCTION__);
l2tp_log (LOG_NOTICE,
"Call established with %s, Local: %d, Remote: %d, Serial: %d (ref=%u/%u)\n",
IPADDY (t->peer.sin_addr), c->ourcid, c->cid,
c->serno, t->refme, t->refhim);
control_xmit (buf);
po = NULL;
po = add_opt (po, "passive");
po = add_opt (po, "nodetach");
if (c->lac)
{
if (c->lac->defaultroute)
po = add_opt (po, "defaultroute");
strncpy (ip1, IPADDY (c->lac->localaddr), sizeof (ip1));
strncpy (ip2, IPADDY (c->lac->remoteaddr), sizeof (ip2));
#ifdef IP_ALLOCATION
po = add_opt (po, "%s:%s", c->lac->localaddr ? ip1 : "",
c->lac->remoteaddr ? ip2 : "");
#endif
if (c->lac->authself)
{
if (c->lac->pap_refuse)
po = add_opt (po, "refuse-pap");
if (c->lac->chap_refuse)
po = add_opt (po, "refuse-chap");
}
else
{
po = add_opt (po, "refuse-pap");
po = add_opt (po, "refuse-chap");
}
if (c->lac->authpeer)
{
po = add_opt (po, "auth");
if (c->lac->pap_require)
po = add_opt (po, "require-pap");
if (c->lac->chap_require)
po = add_opt (po, "require-chap");
}
if (c->lac->authname[0])
{
po = add_opt (po, "name");
po = add_opt (po, c->lac->authname);
}
if (c->lac->debug)
po = add_opt (po, "debug");
if (c->lac->password[0])
{
if (pipe (pppd_passwdfd) == -1)
{
l2tp_log (LOG_DEBUG,
"%s: Unable to create password pipe for pppd\n", __FUNCTION__);
return -EINVAL;
}
if (-1 == write (pppd_passwdfd[1], c->lac->password, strlen (c->lac->password)))
{
l2tp_log (LOG_DEBUG,
"%s: Unable to write password to pipe for pppd\n", __FUNCTION__);
close (pppd_passwdfd[1]);
return -EINVAL;
}
close (pppd_passwdfd[1]);
/* clear password if not redialing: paranoid? */
if (!c->lac->redial)
for (i = 0; i < STRLEN; i++)
c->lac->password[i] = '\0';
po = add_opt (po, "plugin");
po = add_opt (po, "passwordfd.so");
po = add_opt (po, "passwordfd");
snprintf (passwdfd_buf, 32, "%d", pppd_passwdfd[0]);
po = add_opt (po, passwdfd_buf);
}
if (c->lac->pppoptfile[0])
{
po = add_opt (po, "file");
po = add_opt (po, c->lac->pppoptfile);
}
};
if (c->lac->pass_peer)
{
po = add_opt (po, "ipparam");
po = add_opt (po, IPADDY (t->peer.sin_addr));
}
start_pppd (c, po);
opt_destroy (po);
if (c->lac)
c->lac->rtries = 0;
if (c->lac->password[0])
close(pppd_passwdfd[0]);
break;
case ICCN:
if (c == t->self)
{
l2tp_log (LOG_DEBUG,
"%s: Peer attempted ICCN on the actual tunnel, not the call",
__FUNCTION__);
return -EINVAL;
}
if (c->txspeed < 1)
{
l2tp_log (LOG_DEBUG,
"%s: Warning: Peer did not specify transmit speed\n", __FUNCTION__);
/* don't refuse the connection over this
c->needclose = -1;
return -EINVAL;
*/
};
if (c->frame < 1)
{
l2tp_log (LOG_DEBUG,
"%s: Warning: Peer did not specify framing type\n", __FUNCTION__);
/* don't refuse the connection over this
c->needclose = -1;
return -EINVAL;
*/
}
c->state = ICCN;
if (get_local_addr(t, c))
return -EINVAL;
strncpy (ip1, IPADDY (c->lns->localaddr), sizeof (ip1));
strncpy (ip2, IPADDY (c->addr), sizeof (ip2));
po = NULL;
po = add_opt (po, "passive");
po = add_opt (po, "nodetach");
po = add_opt (po, "%s:%s", c->lns->localaddr ? ip1 : "", ip2);
if (c->lns->authself)
{
if (c->lns->pap_refuse)
po = add_opt (po, "refuse-pap");
if (c->lns->chap_refuse)
po = add_opt (po, "refuse-chap");
}
else
{
po = add_opt (po, "refuse-pap");
po = add_opt (po, "refuse-chap");
}
if (c->lns->authpeer)
{
po = add_opt (po, "auth");
if (c->lns->pap_require)
po = add_opt (po, "require-pap");