// L2TPNS PPP Stuff
-char const *cvs_id_ppp = "$Id: ppp.c,v 1.63 2005/06/24 06:59:06 bodea Exp $";
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.91 2005/12/15 14:23:03 bodea Exp $";
#include <stdio.h>
#include <string.h>
extern time_t time_now;
extern configt *config;
-static void initccp(tunnelidt t, sessionidt s);
-static uint8_t *add_lcp_auth(uint8_t *b, int size, int authtype);
+static int add_lcp_auth(uint8_t *b, int size, int authtype);
// Process PAP messages
-void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
char user[MAXUSER];
char pass[MAXPASS];
uint16_t hl;
+ uint16_t r;
CSTAT(processpap);
return;
}
+ if (session[s].ppp.phase != Authenticate)
+ {
+ LOG(2, s, t, "PAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
+ return;
+ }
+
{
uint8_t *b = p;
b += 4;
}
LOG(3, s, t, "PAP login %s/%s\n", user, pass);
}
- if (session[s].ip || !sess_local[s].radius)
+
+ if (session[s].ip || !(r = radiusnew(s)))
{
// respond now, either no RADIUS available or already authenticated
- uint8_t b[MAXCONTROL];
+ uint8_t b[MAXETHER];
uint8_t id = p[1];
- uint8_t *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP);
+ uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP);
if (!p) return;
if (session[s].ip)
p[1] = id;
*(uint16_t *) (p + 2) = htons(5); // length
p[4] = 0; // no message
+ tunnelsend(b, 5 + (p - b), t); // send it
+
if (session[s].ip)
{
LOG(3, s, t, "Already an IP allocated: %s (%d)\n",
fmtaddr(htonl(session[s].ip), 0), session[s].ip_pool_index);
-
- session[s].flags &= ~SF_IPCP_ACKED;
}
else
{
- LOG(1, s, t, "No radius session available to authenticate session...\n");
+ LOG(1, s, t, "No RADIUS session available to authenticate session...\n");
+ sessionshutdown(s, "No free RADIUS sessions.", 4, 0);
}
- LOG(3, s, t, "Fallback response to PAP (%s)\n", (session[s].ip) ? "ACK" : "NAK");
- tunnelsend(b, 5 + (p - b), t); // send it
- sessionshutdown(s, "PAP authentication failed.", 3, 0);
}
else
{
- // set up RADIUS request
- uint16_t r = sess_local[s].radius;
-
// Run PRE_AUTH plugins
struct param_pre_auth packet = { &tunnel[t], &session[s], strdup(user), strdup(pass), PPPPAP, 1 };
run_plugins(PLUGIN_PRE_AUTH, &packet);
free(packet.password);
radius[r].id = p[1];
- LOG(3, s, t, "Sending login for %s/%s to radius\n", user, pass);
+ LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);
radiussend(r, RADIUSAUTH);
}
}
// Process CHAP messages
-void processchap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
uint16_t r;
uint16_t hl;
CSTAT(processchap);
LOG_HEX(5, "CHAP", p, l);
- r = sess_local[s].radius;
- if (!r)
- {
- LOG(1, s, t, "Unexpected CHAP message\n");
- STAT(tunnel_rx_errors);
- return;
- }
if (l < 4)
{
sessionshutdown(s, "CHAP length mismatch.", 3, 0);
return;
}
+
+ r = sess_local[s].radius;
+ if (!r)
+ {
+ LOG(3, s, t, "Unexpected CHAP message\n");
+ return;
+ }
+
+ if (session[s].ppp.phase != Authenticate)
+ {
+ LOG(2, s, t, "CHAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
+ return;
+ }
+
if (p[1] != radius[r].id)
{
LOG(1, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
uint8_t *o = (p + 4);
LOG_HEX(5, "PPP LCP Packet", p, l);
- LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_lcp_type((int)*p), ntohs( ((uint16_t *) p)[1]) );
+ LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_code((int)*p), ntohs( ((uint16_t *) p)[1]) );
LOG(4, 0, 0, "Length: %d\n", l);
if (*p != ConfigReq && *p != ConfigRej && *p != ConfigAck)
return;
{
case 1: // Maximum-Receive-Unit
if (length == 4)
- LOG(4, 0, 0, " %s %d\n", lcp_type(type), ntohs(*(uint16_t *)(o + 2)));
+ LOG(4, 0, 0, " %s %d\n", ppp_lcp_option(type), ntohs(*(uint16_t *)(o + 2)));
else
- LOG(4, 0, 0, " %s odd length %d\n", lcp_type(type), length);
+ LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
break;
case 2: // Async-Control-Character-Map
if (length == 6)
{
uint32_t asyncmap = ntohl(*(uint32_t *)(o + 2));
- LOG(4, 0, 0, " %s %x\n", lcp_type(type), asyncmap);
+ LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), asyncmap);
}
else
- LOG(4, 0, 0, " %s odd length %d\n", lcp_type(type), length);
+ LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
break;
case 3: // Authentication-Protocol
if (length == 4)
{
int proto = ntohs(*(uint16_t *)(o + 2));
- LOG(4, 0, 0, " %s 0x%x (%s)\n", lcp_type(type), proto,
+ LOG(4, 0, 0, " %s 0x%x (%s)\n", ppp_lcp_option(type), proto,
proto == PPPPAP ? "PAP" : "UNSUPPORTED");
}
else if (length == 5)
{
int proto = ntohs(*(uint16_t *)(o + 2));
- int algo = *(uint8_t *)(o + 4);
- LOG(4, 0, 0, " %s 0x%x 0x%x (%s)\n", lcp_type(type), proto, algo,
+ int algo = *(o + 4);
+ LOG(4, 0, 0, " %s 0x%x 0x%x (%s)\n", ppp_lcp_option(type), proto, algo,
(proto == PPPCHAP && algo == 5) ? "CHAP MD5" : "UNSUPPORTED");
}
else
- LOG(4, 0, 0, " %s odd length %d\n", lcp_type(type), length);
+ LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
break;
case 4: // Quality-Protocol
{
uint32_t qp = ntohl(*(uint32_t *)(o + 2));
- LOG(4, 0, 0, " %s %x\n", lcp_type(type), qp);
+ LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), qp);
}
break;
case 5: // Magic-Number
if (length == 6)
{
uint32_t magicno = ntohl(*(uint32_t *)(o + 2));
- LOG(4, 0, 0, " %s %x\n", lcp_type(type), magicno);
+ LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), magicno);
}
else
- LOG(4, 0, 0, " %s odd length %d\n", lcp_type(type), length);
+ LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
break;
case 7: // Protocol-Field-Compression
case 8: // Address-And-Control-Field-Compression
- LOG(4, 0, 0, " %s\n", lcp_type(type));
+ LOG(4, 0, 0, " %s\n", ppp_lcp_option(type));
break;
default:
LOG(2, 0, 0, " Unknown PPP LCP Option type %d\n", type);
}
}
+void lcp_open(sessionidt s, tunnelidt t)
+{
+ // transition to Authentication or Network phase:
+ session[s].ppp.phase = sess_local[s].lcp_authtype ? Authenticate : Network;
+
+ LOG(3, s, t, "LCP: Opened, phase %s\n", ppp_phase(session[s].ppp.phase));
+
+ // LCP now Opened
+ change_state(s, lcp, Opened);
+
+ if (session[s].ppp.phase == Authenticate)
+ {
+ if (sess_local[s].lcp_authtype == AUTHCHAP)
+ sendchap(s, t);
+ }
+ else
+ {
+ // This-Layer-Up
+ sendipcp(s, t);
+ change_state(s, ipcp, RequestSent);
+ // move to passive state for IPv6 (if configured), CCP
+ if (config->ipv6_prefix.s6_addr[0])
+ change_state(s, ipv6cp, Stopped);
+ else
+ change_state(s, ipv6cp, Closed);
+
+ change_state(s, ccp, Stopped);
+ }
+}
+
+static void lcp_restart(sessionidt s)
+{
+ session[s].ppp.phase = Establish;
+ // This-Layer-Down
+ change_state(s, ipcp, Dead);
+ change_state(s, ipv6cp, Dead);
+ change_state(s, ccp, Dead);
+}
+
+static uint8_t *ppp_conf_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+ uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option)
+{
+ if (!*response || **response != ConfigRej)
+ {
+ queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype);
+ if (!queued)
+ return 0;
+
+ *queued = ConfigRej;
+ queued += 4;
+ }
+
+ if ((queued - buf + option[1]) > blen)
+ {
+ LOG(2, s, session[s].tunnel, "PPP overflow for ConfigRej (proto %u, option %u).\n", mtype, *option);
+ return 0;
+ }
+
+ memcpy(queued, option, option[1]);
+ return queued + option[1];
+}
+
+static uint8_t *ppp_conf_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+ uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option,
+ uint8_t *value, size_t vlen)
+{
+ int *nak_sent;
+ switch (mtype)
+ {
+ case PPPLCP: nak_sent = &sess_local[s].lcp.nak_sent; break;
+ case PPPIPCP: nak_sent = &sess_local[s].ipcp.nak_sent; break;
+ case PPPIPV6CP: nak_sent = &sess_local[s].ipv6cp.nak_sent; break;
+ default: return 0; // ?
+ }
+
+ if (*response && **response != ConfigNak)
+ {
+ if (*nak_sent < config->ppp_max_failure) // reject queued
+ return queued;
+
+ return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
+ }
+
+ if (!*response)
+ {
+ if (*nak_sent >= config->ppp_max_failure)
+ return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
+
+ queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype);
+ if (!queued)
+ return 0;
+
+ (*nak_sent)++;
+ *queued = ConfigNak;
+ queued += 4;
+ }
+
+ if ((queued - buf + vlen + 2) > blen)
+ {
+ LOG(2, s, session[s].tunnel, "PPP overflow for ConfigNak (proto %u, option %u).\n", mtype, *option);
+ return 0;
+ }
+
+ *queued++ = *option;
+ *queued++ = vlen + 2;
+ memcpy(queued, value, vlen);
+ return queued + vlen;
+}
+
+static void ppp_code_rej(sessionidt s, tunnelidt t, uint16_t proto,
+ char *pname, uint8_t *p, uint16_t l, uint8_t *buf, size_t size)
+{
+ uint8_t *q;
+ int mru = session[s].mru;
+ if (mru < MINMTU) mru = MINMTU;
+ if (mru > size) mru = size;
+
+ l += 4;
+ if (l > mru) l = mru;
+
+ q = makeppp(buf, size, 0, 0, s, t, proto);
+ if (!q) return;
+
+ *q = CodeRej;
+ *(q + 1) = ++sess_local[s].lcp_ident;
+ *(uint16_t *)(q + 2) = htons(l);
+ memcpy(q + 4, p, l - 4);
+
+ LOG(2, s, t, "Unexpected %s code %s\n", pname, ppp_code(*p));
+ LOG(3, s, t, "%s: send %s\n", pname, ppp_code(*q));
+ if (config->debug > 3) dumplcp(q, l);
+
+ tunnelsend(buf, l + (q - buf), t);
+}
+
// Process LCP messages
-void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
- uint8_t b[MAXCONTROL];
+ uint8_t b[MAXETHER];
uint8_t *q = NULL;
uint32_t magicno = 0;
uint16_t hl;
}
l = hl;
+ if (session[s].die) // going down...
+ return;
+
+ LOG((*p == EchoReq || *p == EchoReply) ? 4 : 3, s, t,
+ "LCP: recv %s\n", ppp_code(*p));
+
+ if (config->debug > 3) dumplcp(p, l);
+
if (*p == ConfigAck)
{
int x = l - 4;
uint8_t *o = (p + 4);
-
- LOG(3, s, t, "LCP: ConfigAck (%d bytes)...\n", l);
- if (config->debug > 3) dumplcp(p, l);
+ int authtype = 0;
while (x > 2)
{
case 3: // Authentication-Protocol
{
int proto = ntohs(*(uint16_t *)(o + 2));
- if (proto == PPPCHAP && *(o + 4) == 5)
- sendchap(t, s);
+ if (proto == PPPPAP)
+ authtype = AUTHPAP;
+ else if (proto == PPPCHAP && *(o + 4) == 5)
+ authtype = AUTHCHAP;
}
break;
o += length;
}
- session[s].flags |= SF_LCP_ACKED;
+ if (!session[s].ip && authtype)
+ sess_local[s].lcp_authtype = authtype;
+
+ switch (session[s].ppp.lcp)
+ {
+ case RequestSent:
+ initialise_restart_count(s, lcp);
+ change_state(s, lcp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "LCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
+ if (session[s].ppp.lcp == Opened)
+ lcp_restart(s);
+
+ sendlcp(s, t);
+ change_state(s, lcp, RequestSent);
+ break;
+
+ case AckSent:
+ lcp_open(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ }
}
else if (*p == ConfigReq)
{
int x = l - 4;
uint8_t *o = (p + 4);
uint8_t *response = 0;
-
- LOG(3, s, t, "LCP: ConfigReq (%d bytes)...\n", l);
- if (config->debug > 3) dumplcp(p, l);
+ static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero
+ static uint8_t authproto[5];
while (x > 2)
{
switch (type)
{
case 1: // Maximum-Receive-Unit
- session[s].mru = ntohs(*(uint16_t *)(o + 2));
+ {
+ uint16_t mru = ntohs(*(uint16_t *)(o + 2));
+ if (mru >= MINMTU)
+ {
+ session[s].mru = mru;
+ break;
+ }
+
+ LOG(3, s, t, " Remote requesting MRU of %u. Rejecting.\n", mru);
+ mru = htons(MRU);
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, (uint8_t *) &mru, sizeof(mru));
+ }
break;
case 2: // Async-Control-Character-Map
if (!ntohl(*(uint32_t *)(o + 2))) // all bits zero is OK
break;
- if (response && *response != ConfigNak) // rej already queued
- break;
-
- LOG(2, s, t, " Remote requesting asyncmap. Rejecting.\n");
- if (!response)
- {
- q = response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP);
- if (!q) break;
- *q = ConfigNak;
- q += 4;
- }
-
- if ((q - b + 11) > sizeof(b))
- {
- LOG(2, s, t, "LCP overflow for asyncmap ConfigNak.\n");
- break;
- }
-
- *q++ = type;
- *q++ = 6;
- memset(q, 0, 4); // asyncmap 0
- q += 4;
+ LOG(3, s, t, " Remote requesting asyncmap. Rejecting.\n");
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap));
break;
case 3: // Authentication-Protocol
{
int proto = ntohs(*(uint16_t *)(o + 2));
char proto_name[] = "0x0000";
- uint8_t *a;
+ int alen;
if (proto == PPPPAP)
{
if (config->radius_authtypes & AUTHPAP)
+ {
+ sess_local[s].lcp_authtype = AUTHPAP;
break;
+ }
strcpy(proto_name, "PAP");
}
{
if (config->radius_authtypes & AUTHCHAP
&& *(o + 4) == 5) // MD5
+ {
+ sess_local[s].lcp_authtype = AUTHCHAP;
break;
+ }
strcpy(proto_name, "CHAP");
}
else
sprintf(proto_name, "%#4.4x", proto);
- if (response && *response != ConfigNak) // rej already queued
- break;
-
- LOG(2, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name);
+ LOG(3, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name);
- if (!response)
- {
- q = response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP);
- if (!q) break;
- *q = ConfigNak;
- q += 4;
- }
+ alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authprefer);
+ if (alen < 2) break; // paranoia
- a = add_lcp_auth(q, sizeof(b) - (q - b), config->radius_authprefer);
- if (!a)
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+ if (q && *response == ConfigNak &&
+ config->radius_authtypes != config->radius_authprefer)
{
- LOG(2, s, t, "LCP overflow for %s ConfigNak.\n", proto_name);
- break;
- }
-
- q = a;
-
- if (config->radius_authtypes != config->radius_authprefer)
- {
- a = add_lcp_auth(q, sizeof(b) - (q - b), config->radius_authtypes & ~config->radius_authprefer);
- if (!a)
- {
- LOG(2, s, t, "LCP overflow for %s ConfigNak.\n", proto_name);
- break;
- }
-
- q = a;
+ // alternate type
+ alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authtypes & ~config->radius_authprefer);
+ if (alen < 2) break;
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
}
break;
break;
default: // Reject any unknown options
- LOG(2, s, t, " Rejecting PPP LCP Option type %d\n", type);
- if (!response || *response != ConfigRej) // drop nak in favour of rej
- {
- q = response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP);
- if (!q) break;
- *q = ConfigRej;
- q += 4;
- }
-
- if ((q - b + length) > sizeof(b))
- {
- LOG(2, s, t, "LCP overflow for ConfigRej (type=%d).\n", type);
- break;
- }
-
- memcpy(q, o, length);
- q += length;
+ LOG(3, s, t, " Rejecting unknown PPP LCP option %d\n", type);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
}
x -= length;
o += length;
else
{
// Send packet back as ConfigAck
- response = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPLCP);
if (!response) return;
*response = ConfigAck;
}
- LOG(3, s, t, "Sending %s\n", ppp_lcp_type(*response));
- tunnelsend(b, l + response - b, t);
+ switch (session[s].ppp.lcp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
- if (!(session[s].flags & SF_LCP_ACKED))
- sendlcp(t, s, config->radius_authprefer);
+ case Stopped:
+ initialise_restart_count(s, lcp);
+ sendlcp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+ else
+ change_state(s, lcp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ lcp_open(s, t);
+
+ break;
+
+ case Opened:
+ lcp_restart(s);
+ sendlcp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+ else
+ change_state(s, lcp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ return;
+ }
+
+ LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
+ if (config->debug > 3) dumplcp(response, l);
+
+ tunnelsend(b, l + (response - b), t);
}
- else if (*p == ConfigNak)
+ else if (*p == ConfigNak || *p == ConfigRej)
{
int x = l - 4;
uint8_t *o = (p + 4);
int authtype = -1;
- LOG(3, s, t, "LCP: ConfigNak (%d bytes)...\n", l);
- if (config->debug > 3) dumplcp(p, l);
-
while (x > 2)
{
int type = o[0];
switch (type)
{
case 1: // Maximum-Receive-Unit
- session[s].mru = ntohs(*(uint16_t *)(o + 2));
- LOG(3, s, t, " Remote requested MRU of %u\n", session[s].mru);
+ if (*p == ConfigNak)
+ {
+ sess_local[s].ppp_mru = ntohs(*(uint16_t *)(o + 2));
+ LOG(3, s, t, " Remote requested MRU of %u\n", sess_local[s].ppp_mru);
+ }
+ else
+ {
+ sess_local[s].ppp_mru = 0;
+ LOG(3, s, t, " Remote rejected MRU negotiation\n");
+ }
+
break;
case 3: // Authentication-Protocol
if (authtype > 0)
break;
+ if (*p == ConfigNak)
{
int proto = ntohs(*(uint16_t *)(o + 2));
if (proto == PPPPAP)
proto);
}
}
+ else
+ {
+ LOG(2, s, t, "LCP: remote rejected auth negotiation\n");
+ authtype = 0; // shutdown
+ }
break;
default:
- LOG(2, s, t, " Remote NAKed LCP type %u?\n", type);
+ LOG(2, s, t, "LCP: remote sent %s for type %u?\n", ppp_code(*p), type);
+ sessionshutdown(s, "Unable to negotiate LCP.", 3, 0);
break;
}
x -= length;
return;
}
- if (authtype == -1)
- authtype = config->radius_authprefer;
+ if (authtype > 0)
+ sess_local[s].lcp_authtype = authtype;
+
+ switch (session[s].ppp.lcp)
+ {
+ case Closed:
+ case Stopped:
+ {
+ uint8_t *response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+
+ LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
+ if (config->debug > 3) dumplcp(response, l);
+
+ tunnelsend(b, l + (response - b), t);
+ }
+ break;
+
+ case RequestSent:
+ case AckSent:
+ initialise_restart_count(s, lcp);
+ sendlcp(s, t);
+ break;
+
+ case AckReceived:
+ LOG(2, s, t, "LCP: ConfigNak in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
+ sendlcp(s, t);
+ break;
+
+ case Opened:
+ lcp_restart(s);
+ sendlcp(s, t);
+ break;
- sendlcp(t, s, authtype);
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ return;
+ }
}
else if (*p == TerminateReq)
{
- LOG(3, s, t, "LCP: Received TerminateReq. Sending TerminateAck\n");
*p = TerminateAck; // close
- q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP);
if (!q) return;
+
+ LOG(3, s, t, "LCP: send %s\n", ppp_code(*q));
+ if (config->debug > 3) dumplcp(q, l);
+
tunnelsend(b, l + (q - b), t); // send it
sessionshutdown(s, "Remote end closed connection.", 3, 0);
}
}
else if (*p == ProtocolRej)
{
- if (*(uint16_t *) (p+4) == htons(PPPIPV6CP))
+ uint16_t proto = 0;
+
+ if (l > 4)
+ {
+ proto = *(p+4);
+ if (l > 5 && !(proto & 1))
+ {
+ proto <<= 8;
+ proto |= *(p+5);
+ }
+ }
+
+ if (proto == PPPIPV6CP)
{
LOG(3, s, t, "IPv6 rejected\n");
- session[s].flags |= SF_IPV6_NACKED;
+ change_state(s, ipv6cp, Closed);
}
else
{
- LOG(1, s, t, "Unexpected LCP protocol reject 0x%X\n",
- ntohs(*(uint16_t *) (p+4)));
- STAT(tunnel_rx_errors);
+ LOG(3, s, t, "LCP protocol reject: 0x%04X\n", proto);
}
}
else if (*p == EchoReq)
{
- LOG(5, s, t, "LCP: Received EchoReq. Sending EchoReply\n");
*p = EchoReply; // reply
*(uint32_t *) (p + 4) = htonl(session[s].magic); // our magic number
- q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP);
if (!q) return;
+
+ LOG(4, s, t, "LCP: send %s\n", ppp_code(*q));
+ if (config->debug > 3) dumplcp(q, l);
+
tunnelsend(b, l + (q - b), t); // send it
}
else if (*p == EchoReply)
{
// Ignore it, last_packet time is set earlier than this.
}
- else if (*p == IdentRequest)
- {
- *p = CodeRej;
- if (l > MAXCONTROL)
- {
- LOG(1, s, t, "Truncated Ident Packet (length=%d) to 1400 bytes\n", l);
- l = 1400;
- }
- q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
- if (!q) return;
- LOG_HEX(5, "LCPIdentRej", q, l + 4);
- tunnelsend(b, 12 + 4 + l, t);
- }
- else
+ else if (*p != CodeRej)
{
- LOG(1, s, t, "Unexpected LCP code %d\n", *p);
- STAT(tunnel_rx_errors);
+ ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b));
}
}
-// find a PPP option, returns point to option, or 0 if not found
-static uint8_t *findppp(uint8_t *b, uint8_t mtype)
+static void ipcp_open(sessionidt s, tunnelidt t)
{
- uint16_t l = ntohs(*(uint16_t *) (b + 2));
- if (l < 4)
- return 0;
- b += 4;
- l -= 4;
- while (l)
+ LOG(3, s, t, "IPCP: Opened, session is now active\n");
+
+ change_state(s, ipcp, Opened);
+
+ if (!(session[s].walled_garden || session[s].flags & SESSION_STARTED))
{
- if (l < b[1] || !b[1])
- return 0; // faulty
- if (*b == mtype)
- return b;
- l -= b[1];
- b += b[1];
+ uint16_t r = radiusnew(s);
+ if (r)
+ {
+ radiussend(r, RADIUSSTART); // send radius start
+
+ // don't send further Start records if IPCP is restarted
+ session[s].flags |= SESSION_STARTED;
+ cluster_send_session(s);
+ }
+ }
+
+ // start IPv6 if configured and still in passive state
+ if (session[s].ppp.ipv6cp == Stopped)
+ {
+ sendipv6cp(s, t);
+ change_state(s, ipv6cp, RequestSent);
}
- return 0;
}
// Process IPCP messages
-void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
+ uint8_t b[MAXETHER];
+ uint8_t *q = 0;
uint16_t hl;
CSTAT(processipcp);
}
l = hl;
+ if (session[s].ppp.phase < Network)
+ {
+ LOG(2, s, t, "IPCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+ return;
+ }
+
+ LOG(3, s, t, "IPCP: recv %s\n", ppp_code(*p));
+
if (*p == ConfigAck)
{
- // happy with our IPCP
- uint16_t r = sess_local[s].radius;
- if ((!r || radius[r].state == RADIUSIPCP) && !session[s].walled_garden)
+ switch (session[s].ppp.ipcp)
{
- if (!r)
- r = radiusnew(s);
- if (r)
- radiussend(r, RADIUSSTART); // send radius start, having got IPCP at last
- }
- session[s].flags |= SF_IPCP_ACKED;
-
- LOG(3, s, t, "IPCP Acked, session is now active\n");
+ case RequestSent:
+ initialise_restart_count(s, ipcp);
+ change_state(s, ipcp, AckReceived);
+ break;
- // clear LCP_ACKED/CCP_ACKED flag for possible fast renegotiation for routers
- session[s].flags &= ~(SF_LCP_ACKED|SF_CCP_ACKED);
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "IPCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipcp));
+ sendipcp(s, t);
+ change_state(s, ipcp, RequestSent);
+ break;
- return;
- }
- if (*p != ConfigReq)
- {
- LOG(1, s, t, "Unexpected IPCP code %d\n", *p);
- STAT(tunnel_rx_errors);
- return ;
- }
- LOG(4, s, t, "IPCP ConfigReq received\n");
+ case AckSent:
+ ipcp_open(s, t);
+ break;
- if (!session[s].ip)
- {
- LOG(3, s, t, "Waiting on radius reply\n");
- return; // have to wait on RADIUS reply
+ default:
+ LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+ }
}
- // form a config reply quoting the IP in the session
+ else if (*p == ConfigReq)
{
- uint8_t b[MAXCONTROL];
- uint8_t *i, *q;
+ uint8_t *response = 0;
+ uint8_t *o = p + 4;
+ int length = l - 4;
+ int gotip = 0;
+ in_addr_t addr;
- q = p + 4;
- i = p + l;
- while (q < i && q[1])
- {
- if (*q != 0x81 && *q != 0x83 && *q != 3)
- break;
- q += q[1];
- }
- if (q < i)
+ while (length > 2)
{
- // reject
- uint16_t n = 4;
- i = p + l;
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP)))
- return;
-
- *q = ConfigRej;
- p += 4;
- while (p < i && p[1])
+ switch (*o)
{
- if (*p != 0x81 && *p != 0x83 && *p != 3)
+ case 3: // ip address
+ gotip++; // seen address
+ if (o[1] != 6 || o[1] > length) return;
+
+ addr = htonl(session[s].ip);
+ if (memcmp(o + 2, &addr, (sizeof addr)))
{
- LOG(2, s, t, "IPCP reject %d\n", *p);
- memcpy(q + n, p, p[1]);
- n += p[1];
+ uint8_t *oq = q;
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ if (!q || (q != oq && *response == ConfigRej))
+ {
+ sessionshutdown(s, "Can't negotiate IPCP.", 3, 0);
+ return;
+ }
}
- p += p[1];
- }
- *(uint16_t *) (q + 2) = htons(n);
- LOG(4, s, t, "Sending ConfigRej\n");
- tunnelsend(b, n + (q - b), t); // send it
- }
- else
- {
- LOG(4, s, t, "Sending ConfigAck\n");
- *p = ConfigAck;
- if ((i = findppp(p, 0x81))) // Primary DNS address
- {
- if (*(uint32_t *) (i + 2) != htonl(session[s].dns1))
+
+ break;
+
+ case 129: // primary DNS
+ if (o[1] != 6 || o[1] > length) return;
+
+ addr = htonl(session[s].dns1);
+ if (memcmp(o + 2, &addr, (sizeof addr)))
{
- *(uint32_t *) (i + 2) = htonl(session[s].dns1);
- *p = ConfigNak;
- LOG(5, s, t, " DNS1 = %s\n",
- fmtaddr(htonl(session[s].dns1), 0));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ if (!q) return;
}
- }
- if ((i = findppp(p, 0x83))) // Secondary DNS address (TBA, is it)
- {
- if (*(uint32_t *) (i + 2) != htonl(session[s].dns2))
+
+ break;
+
+ case 131: // secondary DNS
+ if (o[1] != 6 || o[1] > length) return;
+
+ addr = htonl(session[s].dns2);
+ if (memcmp(o + 2, &addr, sizeof(addr)))
{
- *(uint32_t *) (i + 2) = htonl(session[s].dns2);
- *p = ConfigNak;
- LOG(5, s, t, " DNS2 = %s\n",
- fmtaddr(htonl(session[s].dns2), 0));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ if (!q) return;
}
+
+ break;
+
+ default:
+ LOG(2, s, t, " Rejecting PPP IPCP Option type %d\n", *o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
+ if (!q) return;
}
- i = findppp(p, 3); // IP address
- if (!i || i[1] != 6)
- {
- LOG(1, s, t, "No IP in IPCP request\n");
- STAT(tunnel_rx_errors);
- return ;
- }
- if (*(uint32_t *) (i + 2) != htonl(session[s].ip))
- {
- *(uint32_t *) (i + 2) = htonl(session[s].ip);
- *p = ConfigNak;
- LOG(4, s, t, " No, a ConfigNak, client is requesting IP - sending %s\n",
- fmtaddr(htonl(session[s].ip), 0));
- }
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP)))
- return;
- tunnelsend(b, l + (q - b), t); // send it
+ length -= o[1];
+ o += o[1];
+ }
+
+ if (response)
+ {
+ l = q - response; // IPCP packet length
+ *((uint16_t *) (response + 2)) = htons(l); // update header
+ }
+ else if (gotip)
+ {
+ // Send packet back as ConfigAck
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP);
+ if (!response) return;
+ *response = ConfigAck;
+ }
+ else
+ {
+ LOG(1, s, t, "No IP in IPCP request\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+
+ switch (session[s].ppp.ipcp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPCP);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
+
+ case Stopped:
+ initialise_restart_count(s, ipcp);
+ sendipcp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+ else
+ change_state(s, ipcp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ ipcp_open(s, t);
+
+ break;
+
+ case Opened:
+ initialise_restart_count(s, ipcp);
+ sendipcp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+ else
+ change_state(s, ipcp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+ return;
}
+
+ LOG(3, s, t, "IPCP: send %s\n", ppp_code(*response));
+ tunnelsend(b, l + (response - b), t);
+ }
+ else if (*p == TerminateReq)
+ {
+ *p = TerminateAck;
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP);
+ if (!q) return;
+ LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t);
+ change_state(s, ipcp, Stopped);
+ }
+ else if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b));
}
}
+static void ipv6cp_open(sessionidt s, tunnelidt t)
+{
+ LOG(3, s, t, "IPV6CP: Opened\n");
+
+ change_state(s, ipv6cp, Opened);
+ if (session[s].ipv6prefixlen)
+ route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 1);
+
+ // Send an initial RA (TODO: Should we send these regularly?)
+ send_ipv6_ra(s, t, NULL);
+}
+
// Process IPV6CP messages
-void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
+ uint8_t b[MAXETHER];
+ uint8_t *q = 0;
+ uint16_t hl;
CSTAT(processipv6cp);
STAT(tunnel_rx_errors);
return ;
}
- if (*p == ConfigAck)
- {
- // happy with our IPV6CP
- session[s].flags |= SF_IPV6CP_ACKED;
- LOG(3, s, t, "IPV6CP Acked, IPv6 is now active\n");
- // Add a routed block if configured.
- if (session[s].ipv6prefixlen)
- {
- route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 1);
- session[s].flags |= SF_IPV6_ROUTED;
- }
-
- // Send an initial RA (TODO: Should we send these regularly?)
- send_ipv6_ra(t, s, NULL);
- return;
- }
- if (*p != ConfigReq)
+ if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
{
- LOG(1, s, t, "Unexpected IPV6CP code %d\n", *p);
+ LOG(1, s, t, "Length mismatch IPV6CP %u/%u\n", hl, l);
STAT(tunnel_rx_errors);
- return;
+ return ;
}
+ l = hl;
- LOG(4, s, t, "IPV6CP ConfigReq received\n");
- if (ntohs(*(uint16_t *) (p + 2)) > l)
+ if (session[s].ppp.phase < Network)
{
- LOG(1, s, t, "Length mismatch IPV6CP %d/%d\n", ntohs(*(uint16_t *) (p + 2)), l);
- STAT(tunnel_rx_errors);
- return ;
+ LOG(2, s, t, "IPV6CP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+ return;
}
+
+ LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p));
+
if (!session[s].ip)
{
- LOG(3, s, t, "Waiting on radius reply\n");
- return; // have to wait on RADIUS reply
+ LOG(3, s, t, "IPV6CP: no IPv4 address (IPCP in state %s)\n", ppp_state(session[s].ppp.ipcp));
+ return; // need IPCP to complete...
}
- // form a config reply quoting the IP in the session
- {
- uint8_t b[MAXCONTROL];
- uint8_t *i,
- *q;
- l = ntohs(*(uint16_t *) (p + 2)); // We must use length from IPV6CP len field
- q = p + 4;
- i = p + l;
- while (q < i && q[1])
+ if (*p == ConfigAck)
+ {
+ switch (session[s].ppp.ipv6cp)
{
- if (*q != 1)
- break;
- q += q[1];
+ case RequestSent:
+ initialise_restart_count(s, ipv6cp);
+ change_state(s, ipv6cp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "IPV6CP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipv6cp));
+ sendipv6cp(s, t);
+ change_state(s, ipv6cp, RequestSent);
+ break;
+
+ case AckSent:
+ ipv6cp_open(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
}
- if (q < i)
+ }
+ else if (*p == ConfigReq)
+ {
+ uint8_t *response = 0;
+ uint8_t *o = p + 4;
+ int length = l - 4;
+ int gotip = 0;
+ uint8_t ident[8];
+
+ while (length > 2)
{
- // reject
- uint16_t n = 4;
- i = p + l;
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP)))
+ switch (*o)
{
- LOG(2, s, t, "Failed to send IPV6CP ConfigRej\n");
- return;
- }
- *q = ConfigRej;
- p += 4;
- while (p < i && p[1])
- {
- if (*p != 1)
+ case 1: // interface identifier
+ gotip++; // seen address
+ if (o[1] != 10 || o[1] > length) return;
+
+ *(uint32_t *) ident = htonl(session[s].ip);
+ *(uint32_t *) (ident + 4) = 0;
+
+ if (memcmp(o + 2, ident, sizeof(ident)))
{
- LOG(2, s, t, "IPV6CP reject %d\n", *p);
- memcpy(q + n, p, p[1]);
- n += p[1];
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
+ if (!q) return;
}
- p += p[1];
+
+ break;
+
+ default:
+ LOG(2, s, t, " Rejecting PPP IPV6CP Option type %d\n", *o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
+ if (!q) return;
}
- *(uint16_t *) (q + 2) = htons(n);
- LOG(4, s, t, "Sending ConfigRej\n");
- tunnelsend(b, n + (q - b), t); // send it
+
+ length -= o[1];
+ o += o[1];
+ }
+
+ if (response)
+ {
+ l = q - response; // IPV6CP packet length
+ *((uint16_t *) (response + 2)) = htons(l); // update header
+ }
+ else if (gotip)
+ {
+ // Send packet back as ConfigAck
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP);
+ if (!response) return;
+ *response = ConfigAck;
}
else
{
- LOG(4, s, t, "Sending ConfigAck\n");
- *p = ConfigAck;
- i = findppp(p, 1); // IP address
- if (!i || i[1] != 10)
- {
- LOG(1, s, t, "No IP in IPV6CP request\n");
- STAT(tunnel_rx_errors);
- return ;
- }
- if ((*(uint32_t *) (i + 2) != htonl(session[s].ip)) ||
- (*(uint32_t *) (i + 6) != 0))
- {
- *(uint32_t *) (i + 2) = htonl(session[s].ip);
- *(uint32_t *) (i + 6) = 0;
- *p = ConfigNak;
- LOG(4, s, t,
- " No, a ConfigNak, client is "
- "requesting IP - sending %s\n",
- fmtaddr(htonl(session[s].ip), 0));
- }
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP)))
- {
- LOG(2, s, t, " Failed to send IPV6CP packet.\n");
- return;
- }
- tunnelsend(b, l + (q - b), t); // send it
+ LOG(1, s, t, "No interface identifier in IPV6CP request\n");
+ STAT(tunnel_rx_errors);
+ return;
}
+
+ switch (session[s].ppp.ipv6cp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPV6CP);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
+
+ case Stopped:
+ initialise_restart_count(s, ipv6cp);
+ sendipv6cp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+ else
+ change_state(s, ipv6cp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ ipv6cp_open(s, t);
+
+ break;
+
+ case Opened:
+ initialise_restart_count(s, ipv6cp);
+ sendipv6cp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+ else
+ change_state(s, ipv6cp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+ return;
+ }
+
+ LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*response));
+ tunnelsend(b, l + (response - b), t);
+ }
+ else if (*p == TerminateReq)
+ {
+ *p = TerminateAck;
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP);
+ if (!q) return;
+ LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t);
+ change_state(s, ipv6cp, Stopped);
+ }
+ else if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b));
}
}
//
// This MUST be called with at least 4 byte behind 'p'.
// (i.e. this routine writes to p[-4]).
-void processipin(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
in_addr_t ip;
LOG_HEX(5, "IP", p, l);
+ if (l < 20)
+ {
+ LOG(1, s, t, "IP packet too short %d\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
ip = ntohl(*(uint32_t *)(p + 12));
if (l > MAXETHER)
return ;
}
+ if (session[s].ppp.phase != Network || session[s].ppp.ipcp != Opened)
+ return;
+
// no spoof (do sessionbyip to handled statically routed subnets)
if (ip != session[s].ip && sessionbyip(htonl(ip)) != s)
{
if (session[s].filter_in && !ip_filter(p, l, session[s].filter_in - 1))
return;
+ // adjust MSS on SYN and SYN,ACK packets with options
+ if ((ntohs(*(uint16_t *) (p + 6)) & 0x1fff) == 0 && p[9] == IPPROTO_TCP) // first tcp fragment
+ {
+ int ihl = (p[0] & 0xf) * 4; // length of IP header
+ if (l >= ihl + 20 && (p[ihl + 13] & TCP_FLAG_SYN) && ((p[ihl + 12] >> 4) > 5))
+ adjust_tcp_mss(s, t, p, l, p + ihl);
+ }
+
// Add on the tun header
p -= 4;
*(uint32_t *) p = htonl(PKTIP);
//
// This MUST be called with at least 4 byte behind 'p'.
// (i.e. this routine writes to p[-4]).
-void processipv6in(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
struct in6_addr ip;
in_addr_t ipv4;
return ;
}
+ if (session[s].ppp.phase != Network || session[s].ppp.ipv6cp != Opened)
+ return;
+
// no spoof
if (ipv4 != session[s].ip && memcmp(&config->ipv6_prefix, &ip, 8) && sessionbyipv6(ip) != s)
{
*(uint32_t *)(p + 34) == 0 &&
*(p + 38) == 0 && *(p + 39) == 2 && *(p + 40) == 133) {
LOG(3, s, t, "Got IPv6 RS\n");
- send_ipv6_ra(t, s, &ip);
+ send_ipv6_ra(s, t, &ip);
return;
}
// Process CCP messages
-void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
+void processccp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
- uint8_t b[MAXCONTROL];
+ uint8_t b[MAXETHER];
uint8_t *q;
CSTAT(processccp);
LOG_HEX(5, "CCP", p, l);
- switch (l > 1 ? *p : 0)
+
+ if (session[s].ppp.phase < Network)
{
- case ConfigAck:
- session[s].flags |= SF_CCP_ACKED;
+ LOG(2, s, t, "CCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
return;
+ }
- case ConfigReq:
- if (l < 6) // accept no compression
+ if (l < 1)
+ {
+ LOG(1, s, t, "Short CCP packet\n");
+ STAT(tunnel_rx_errors);
+ }
+
+ LOG(3, s, t, "CCP: recv %s\n", ppp_code(*p));
+ if (*p == ConfigAck)
+ {
+ switch (session[s].ppp.ccp)
{
- *p = ConfigAck;
+ case RequestSent:
+ initialise_restart_count(s, ccp);
+ change_state(s, ccp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "CCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ccp));
+ sendccp(s, t);
+ change_state(s, ccp, RequestSent);
+ break;
+
+ case AckSent:
+ LOG(3, s, t, "CCP: Opened\n");
+ change_state(s, ccp, Opened);
break;
+
+ default:
+ LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
}
+ }
+ else if (*p == ConfigReq)
+ {
+ if (l < 6) // accept no compression
+ *p = ConfigAck;
+ else // compression requested--reject
+ *p = ConfigRej;
- // compression requested--reject
- *p = ConfigRej;
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP);
+ if (!q) return;
- // send CCP request for no compression for our end if not negotiated
- if (!(session[s].flags & SF_CCP_ACKED))
- initccp(t, s);
+ switch (session[s].ppp.ccp)
+ {
+ case Closed:
+ q = makeppp(b, sizeof(b), p, 2, s, t, PPPCCP);
+ if (!q) return;
+ *q = TerminateAck;
+ *((uint16_t *) (q + 2)) = htons(l = 4);
+ break;
- break;
+ case Stopped:
+ initialise_restart_count(s, ccp);
+ sendccp(s, t);
+ if (*q == ConfigAck)
+ change_state(s, ccp, AckSent);
+ else
+ change_state(s, ccp, RequestSent);
- case TerminateReq:
- *p = TerminateAck;
- break;
+ break;
- default:
- if (l > 1)
- LOG(1, s, t, "Unexpected CCP request code %d\n", *p);
- else
- LOG(1, s, t, "Short CCP packet\n");
+ case RequestSent:
+ if (*q == ConfigAck)
+ change_state(s, ccp, AckSent);
- STAT(tunnel_rx_errors);
- return;
- }
+ break;
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP)))
- return;
+ case AckReceived:
+ if (*q == ConfigAck)
+ change_state(s, ccp, Opened);
+
+ break;
+
+ case Opened:
+ initialise_restart_count(s, ccp);
+ sendccp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*q == ConfigAck)
+ change_state(s, ccp, AckSent);
+ else
+ change_state(s, ccp, RequestSent);
+
+ break;
- tunnelsend(b, l + (q - b), t); // send it
+ default:
+ LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
+ return;
+ }
+
+ LOG(3, s, t, "CCP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t);
+ }
+ else if (*p == TerminateReq)
+ {
+ *p = TerminateAck;
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP);
+ if (!q) return;
+ LOG(3, s, t, "CCP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t);
+ change_state(s, ccp, Stopped);
+ }
+ else if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPCCP, "CCP", p, l, b, sizeof(b));
+ }
}
// send a CHAP challenge
-void sendchap(tunnelidt t, sessionidt s)
+void sendchap(sessionidt s, tunnelidt t)
{
- uint8_t b[MAXCONTROL];
- uint16_t r = sess_local[s].radius;
+ uint8_t b[MAXETHER];
+ uint16_t r;
uint8_t *q;
CSTAT(sendchap);
+ r = radiusnew(s);
if (!r)
{
LOG(1, s, t, "No RADIUS to send challenge\n");
STAT(tunnel_tx_errors);
return ;
}
- q = makeppp(b, sizeof(b), 0, 0, t, s, PPPCHAP);
+ q = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP);
if (!q) return;
*q = 1; // challenge
q[1] = radius[r].id; // ID
q[4] = 16; // value size (size of challenge)
memcpy(q + 5, radius[r].auth, 16); // challenge
- strcpy(q + 21, hostname); // our name
+ strcpy((char *) q + 21, hostname); // our name
*(uint16_t *) (q + 2) = htons(strlen(hostname) + 21); // length
tunnelsend(b, strlen(hostname) + 21 + (q - b), t); // send it
}
// fill in a L2TP message with a PPP frame,
// copies existing PPP message and changes magic number if seen
// returns start of PPP frame
-uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, tunnelidt t, sessionidt s, uint16_t mtype)
+uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype)
{
if (size < 12) // Need more space than this!!
{
- static int backtrace_count = 0;
LOG(0, s, t, "makeppp buffer too small for L2TP header (size=%d)\n", size);
- log_backtrace(backtrace_count, 5)
return NULL;
}
*(uint16_t *) (b + 2) = htons(tunnel[t].far); // tunnel
*(uint16_t *) (b + 4) = htons(session[s].far); // session
b += 6;
- if (mtype == PPPLCP || !(session[s].l2tp_flags & SESSIONACFC))
+ if (mtype == PPPLCP || !(session[s].flags & SESSION_ACFC))
{
*(uint16_t *) b = htons(0xFF03); // HDLC header
b += 2;
}
- if (mtype < 0x100 && session[s].l2tp_flags & SESSIONPFC)
+ if (mtype < 0x100 && session[s].flags & SESSION_PFC)
*b++ = mtype;
else
{
if (l + 12 > size)
{
- static int backtrace_count = 0;
LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%d)\n", size, l + 12);
- log_backtrace(backtrace_count, 5)
return NULL;
}
return b;
}
-static uint8_t *add_lcp_auth(uint8_t *b, int size, int authtype)
+static int add_lcp_auth(uint8_t *b, int size, int authtype)
{
+ int len = 0;
if ((authtype == AUTHCHAP && size < 5) || size < 4)
return 0;
*b++ = 3; // Authentication-Protocol
if (authtype == AUTHCHAP)
{
- *b++ = 5; // length
+ len = *b++ = 5; // length
*(uint16_t *) b = htons(PPPCHAP); b += 2;
*b++ = 5; // MD5
}
else if (authtype == AUTHPAP)
{
- *b++ = 4; // length
+ len = *b++ = 4; // length
*(uint16_t *) b = htons(PPPPAP); b += 2;
}
else
LOG(0, 0, 0, "add_lcp_auth called with unsupported auth type %d\n", authtype);
}
- return b;
+ return len;
}
// Send initial LCP ConfigReq for MRU, authentication type and magic no
-void sendlcp(tunnelidt t, sessionidt s, int authtype)
+void sendlcp(sessionidt s, tunnelidt t)
{
- char b[500], *q, *l;
+ uint8_t b[500], *q, *l;
+ int authtype = sess_local[s].lcp_authtype;
- if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP)))
+ if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPLCP)))
return;
- LOG(4, s, t, "Sending LCP ConfigReq for %s\n",
- authtype == AUTHCHAP ? "CHAP" : "PAP");
-
- if (!session[s].mru)
- session[s].mru = DEFAULT_MRU;
+ LOG(3, s, t, "LCP: send ConfigReq%s%s%s\n",
+ authtype ? " (" : "",
+ authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : "",
+ authtype ? ")" : "");
l = q;
*l++ = ConfigReq;
- *l++ = (time_now % 255) + 1; // ID
+ *l++ = ++sess_local[s].lcp_ident; // ID
l += 2; //Save space for length
- *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
- *(uint16_t *) l = htons(session[s].mru); l += 2;
+ if (sess_local[s].ppp_mru)
+ {
+ *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
+ *(uint16_t *) l = htons(sess_local[s].ppp_mru); l += 2;
+ }
- l = add_lcp_auth(l, sizeof(b) - (l - b), authtype);
+ if (authtype)
+ l += add_lcp_auth(l, sizeof(b) - (l - b), authtype);
*l++ = 5; *l++ = 6; // Magic-Number (length 6)
*(uint32_t *) l = htonl(session[s].magic);
*(uint16_t *)(q + 2) = htons(l - q); // Length
LOG_HEX(5, "PPPLCP", q, l - q);
+ if (config->debug > 3) dumplcp(q, l - q);
+
tunnelsend(b, (l - b), t);
+ restart_timer(s, lcp);
}
// Send CCP request for no compression
-static void initccp(tunnelidt t, sessionidt s)
+void sendccp(sessionidt s, tunnelidt t)
{
- char b[500], *q;
+ uint8_t b[500], *q;
- if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP)))
+ if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPCCP)))
return;
- LOG(4, s, t, "Sending CCP ConfigReq for no compression\n");
+ LOG(3, s, t, "CCP: send ConfigReq (no compression)\n");
+
*q = ConfigReq;
- *(uint8_t *)(q + 1) = (time_now % 255) + 1; // ID
+ *(q + 1) = ++sess_local[s].lcp_ident; // ID
*(uint16_t *)(q + 2) = htons(4); // Length
LOG_HEX(5, "PPPCCP", q, 4);
tunnelsend(b, (q - b) + 4 , t);
+ restart_timer(s, ccp);
+}
+
+// Reject unknown/unconfigured protocols
+void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto)
+{
+
+ uint8_t buf[MAXETHER];
+ uint8_t *q;
+ int mru = session[s].mru;
+ if (mru < MINMTU) mru = MINMTU;
+ if (mru > sizeof(buf)) mru = sizeof(buf);
+
+ l += 6;
+ if (l > mru) l = mru;
+
+ q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP);
+ if (!q) return;
+
+ *q = ProtocolRej;
+ *(q + 1) = ++sess_local[s].lcp_ident;
+ *(uint16_t *)(q + 2) = htons(l);
+ *(uint16_t *)(q + 4) = htons(proto);
+ memcpy(q + 6, p, l - 6);
+
+ if (proto == PPPIPV6CP)
+ LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
+ else
+ LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
+
+ tunnelsend(buf, l + (q - buf), t);
}
projects / l2tpns.git / blobdiff