// L2TPNS PPP Stuff
-char const *cvs_id_ppp = "$Id: ppp.c,v 1.11 2004/08/02 06:06:28 fred_nerk Exp $";
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.38 2004/11/30 19:34:57 bodea Exp $";
#include <stdio.h>
#include <string.h>
extern char hostname[];
extern u32 eth_tx;
extern time_t time_now;
-extern struct configt *config;
+extern configt *config;
-void sendccp(tunnelidt t, sessionidt s);
+static void initccp(tunnelidt t, sessionidt s);
// Process PAP messages
-void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void processpap(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
char user[129];
char pass[129];
-
+ u16 hl;
CSTAT(call_processpap);
- log_hex(5, "PAP", p, l);
+ LOG_HEX(5, "PAP", p, l);
if (l < 4)
{
- log(1, 0, s, t, "Short PAP %u bytes\n", l);
+ LOG(1, s, t, "Short PAP %u bytes\n", l);
STAT(tunnel_rx_errors);
return ;
}
- if (*p != 1)
+
+ if ((hl = ntohs(*(u16 *) (p + 2))) > l)
{
- log(1, 0, s, t, "Unexpected PAP code %d\n", *p);
+ LOG(1, s, t, "Length mismatch PAP %u/%u\n", hl, l);
STAT(tunnel_rx_errors);
return ;
}
- if (ntohs(*(u16 *) (p + 2)) > l)
+ l = hl;
+
+ if (*p != 1)
{
- log(1, 0, s, t, "Length mismatch PAP %d/%d\n", ntohs(*(u16 *) (p + 2)), l);
+ LOG(1, s, t, "Unexpected PAP code %d\n", *p);
STAT(tunnel_rx_errors);
return ;
}
+
{
u8 *b = p;
b += 4;
if (*b && *b < sizeof(pass))
memcpy(pass, b + 1, *b);
pass[*b] = 0;
- log(3, 0, s, t, "PAP login %s/%s\n", user, pass);
+ LOG(3, s, t, "PAP login %s/%s\n", user, pass);
}
if (session[s].ip || !session[s].radius)
{
u8 b[MAXCONTROL];
u8 id = p[1];
u8 *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP);
- if (!p) { // Failed to make ppp header!
- log(1,0,0,0, "Failed to make PPP header in process pap!\n");
- return;
- }
+ if (!p) return;
+
if (session[s].ip)
- *p = 2; // ACK
+ *p = 2; // ACK
else
- *p = 3; // cant authorise
+ *p = 3; // cant authorise
p[1] = id;
- *(u16 *) (p + 2) = htons(5); // length
- p[4] = 0; // no message
+ *(u16 *) (p + 2) = htons(5); // length
+ p[4] = 0; // no message
if (session[s].ip)
{
- log(3, session[s].ip, s, t, "%d Already an IP allocated: %s (%d)\n", getpid(), inet_toa(htonl(session[s].ip)), session[s].ip_pool_index);
+ 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, 0, s, t, "No radius session available to authenticate session...\n");
+ LOG(1, s, t, "No radius session available to authenticate session...\n");
}
- log(3, 0, s, t, "Fallback response to PAP (%s)\n", (session[s].ip) ? "ACK" : "NAK");
+ LOG(3, s, t, "Fallback response to PAP (%s)\n", (session[s].ip) ? "ACK" : "NAK");
tunnelsend(b, 5 + (p - b), t); // send it
}
else
- { // set up RADIUS request
+ {
+ // set up RADIUS request
u16 r = session[s].radius;
// Run PRE_AUTH plugins
run_plugins(PLUGIN_PRE_AUTH, &packet);
if (!packet.continue_auth)
{
- log(3, 0, s, t, "A plugin rejected PRE_AUTH\n");
+ LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
if (packet.username) free(packet.username);
if (packet.password) free(packet.password);
return;
free(packet.password);
radius[r].id = p[1];
- log(3, 0, 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, u8 * p, u16 l)
+void processchap(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
u16 r;
- u16 len;
-
+ u16 hl;
CSTAT(call_processchap);
- log_hex(5, "CHAP", p, l);
+ LOG_HEX(5, "CHAP", p, l);
r = session[s].radius;
if (!r)
{
- log(1, 0, s, t, "Unexpected CHAP message\n");
+ LOG(1, s, t, "Unexpected CHAP message\n");
// FIXME: Need to drop the session here.
STAT(tunnel_rx_errors);
return;
}
- if (*p != 2)
+
+ if (l < 4)
{
- log(1, 0, s, t, "Unexpected CHAP response code %d\n", *p);
+ LOG(1, s, t, "Short CHAP %u bytes\n", l);
STAT(tunnel_rx_errors);
- return;
+ return ;
}
- if (p[1] != radius[r].id)
+
+ if ((hl = ntohs(*(u16 *) (p + 2))) > l)
{
- log(1, 0, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
+ LOG(1, s, t, "Length mismatch CHAP %u/%u\n", hl, l);
STAT(tunnel_rx_errors);
return ;
}
- len = ntohs(*(u16 *) (p + 2));
- if (len > l)
+ l = hl;
+
+ if (*p != 2)
+ {
+ LOG(1, s, t, "Unexpected CHAP response code %d\n", *p);
+ STAT(tunnel_rx_errors);
+ return;
+ }
+ if (p[1] != radius[r].id)
{
- log(1, 0, s, t, "Bad CHAP length %d\n", len);
+ LOG(1, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
STAT(tunnel_rx_errors);
return ;
}
- if (p[4] != 16)
+
+ if (l < 5 || p[4] != 16)
{
- log(1, 0, s, t, "Bad CHAP response length %d\n", p[4]);
+ LOG(1, s, t, "Bad CHAP response length %d\n", l < 5 ? -1 : p[4]);
STAT(tunnel_rx_errors);
return ;
}
- if (len - 21 >= sizeof(session[s].user))
+
+ l -= 5;
+ p += 5;
+ if (l < 16 || l - 16 >= sizeof(session[s].user))
{
- log(1, 0, s, t, "CHAP user too long %d\n", len - 21);
+ LOG(1, s, t, "CHAP user too long %d\n", l - 16);
STAT(tunnel_rx_errors);
return ;
}
{
struct param_pre_auth packet = { &tunnel[t], &session[s], NULL, NULL, PPPCHAP, 1 };
- packet.username = calloc(len-20, 1);
- packet.password = calloc(16, 1);
- memcpy(packet.username, p + 21, len - 21);
- memcpy(packet.password, p + 5, 16);
+ packet.password = calloc(17, 1);
+ memcpy(packet.password, p, 16);
+
+ p += 16;
+ l -= 16;
+
+ packet.username = calloc(l + 1, 1);
+ memcpy(packet.username, p, l);
run_plugins(PLUGIN_PRE_AUTH, &packet);
if (!packet.continue_auth)
{
- log(3, 0, s, t, "A plugin rejected PRE_AUTH\n");
+ LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
if (packet.username) free(packet.username);
if (packet.password) free(packet.password);
return;
}
radius[r].chap = 1;
- log(3, 0, s, t, "CHAP login %s\n", session[s].user);
+ LOG(3, s, t, "CHAP login %s\n", session[s].user);
radiussend(r, RADIUSAUTH);
}
-char *ppp_lcp_types[] = {
+static char *ppp_lcp_types[] = {
NULL,
"ConfigReq",
"ConfigAck",
"IdentRequest",
};
-void dumplcp(u8 *p, int l)
+static void dumplcp(u8 *p, int l)
{
- signed int x = l - 4;
+ int x = l - 4;
u8 *o = (p + 4);
- log_hex(5, "PPP LCP Packet", p, l);
- log(4, 0, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_lcp_types[(int)*p], ntohs( ((u16 *) p)[1]) );
- log(4, 0, 0, 0, "Length: %d\n", l);
+ LOG_HEX(5, "PPP LCP Packet", p, l);
+ LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_lcp_types[(int)*p], ntohs( ((u16 *) p)[1]) );
+ LOG(4, 0, 0, "Length: %d\n", l);
if (*p != ConfigReq && *p != ConfigRej && *p != ConfigAck)
return;
int length = o[1];
if (length < 2)
{
- log(4, 0, 0, 0, " Option length is %d...\n", length);
+ LOG(4, 0, 0, " Option length is %d...\n", length);
break;
}
if (type == 0)
{
- log(4, 0, 0, 0, " Option type is 0...\n");
+ LOG(4, 0, 0, " Option type is 0...\n");
x -= length;
o += length;
continue;
{
case 1: // Maximum-Receive-Unit
if (length == 4)
- log(4, 0, 0, 0, " %s %d\n", lcp_types[type], ntohs(*(u16 *)(o + 2)));
+ LOG(4, 0, 0, " %s %d\n", lcp_types[type], ntohs(*(u16 *)(o + 2)));
+ else
+ LOG(4, 0, 0, " %s odd length %d\n", lcp_types[type], length);
+ break;
+ case 2: // Async-Control-Character-Map
+ if (length == 6)
+ {
+ u32 asyncmap = ntohl(*(u32 *)(o + 2));
+ LOG(4, 0, 0, " %s %x\n", lcp_types[type], asyncmap);
+ }
else
- log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length);
+ LOG(4, 0, 0, " %s odd length %d\n", lcp_types[type], length);
break;
case 3: // Authentication-Protocol
+ if (length == 4)
{
- if (length == 4)
- {
int proto = ntohs(*(u16 *)(o + 2));
- log(4, 0, 0, 0, " %s 0x%x (%s)\n", lcp_types[type], proto,
- proto == 0xC223 ? "CHAP" :
- proto == 0xC023 ? "PAP" : "UNKNOWN");
- }
- else
- log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length);
- break;
+ LOG(4, 0, 0, " %s 0x%x (%s)\n", lcp_types[type], proto,
+ proto == PPPCHAP ? "CHAP" :
+ proto == PPPPAP ? "PAP" : "UNKNOWN");
}
+ else
+ LOG(4, 0, 0, " %s odd length %d\n", lcp_types[type], length);
+ break;
case 4: // Quality-Protocol
{
u32 qp = ntohl(*(u32 *)(o + 2));
- log(4, 0, 0, 0, " %s %x\n", lcp_types[type], qp);
- break;
+ LOG(4, 0, 0, " %s %x\n", lcp_types[type], qp);
}
+ break;
case 5: // Magic-Number
+ if (length == 6)
{
- if (length == 6)
- {
u32 magicno = ntohl(*(u32 *)(o + 2));
- log(4, 0, 0, 0, " %s %x\n", lcp_types[type], magicno);
- }
- else
- log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length);
- break;
+ LOG(4, 0, 0, " %s %x\n", lcp_types[type], magicno);
}
+ else
+ LOG(4, 0, 0, " %s odd length %d\n", lcp_types[type], length);
+ break;
case 7: // Protocol-Field-Compression
- {
- log(4, 0, 0, 0, " %s\n", lcp_types[type]);
- break;
- }
case 8: // Address-And-Control-Field-Compression
- {
- log(4, 0, 0, 0, " %s\n", lcp_types[type]);
- break;
- }
+ LOG(4, 0, 0, " %s\n", lcp_types[type]);
+ break;
default:
- log(2, 0, 0, 0, " Unknown PPP LCP Option type %d\n", type);
+ LOG(2, 0, 0, " Unknown PPP LCP Option type %d\n", type);
break;
}
x -= length;
}
// Process LCP messages
-void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void processlcp(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
u8 b[MAXCONTROL];
u8 *q = NULL;
- u32 magicno = 0;
-
+ u32 magicno = 0;
+ u16 hl;
CSTAT(call_processlcp);
- log_hex(5, "LCP", p, l);
+ LOG_HEX(5, "LCP", p, l);
if (l < 4)
{
- log(1, session[s].ip, s, t, "Short LCP %d bytes\n", l);
+ LOG(1, s, t, "Short LCP %d bytes\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
+ if ((hl = ntohs(*(u16 *) (p + 2))) > l)
+ {
+ LOG(1, s, t, "Length mismatch LCP %u/%u\n", hl, l);
STAT(tunnel_rx_errors);
return ;
}
+ l = hl;
+
if (*p == ConfigAck)
{
- log(3, session[s].ip, s, t, "LCP: Discarding ConfigAck\n");
- session[s].flags |= SESSIONLCPACK;
+ LOG(3, s, t, "LCP: Discarding ConfigAck\n");
+ session[s].flags |= SF_LCP_ACKED;
}
else if (*p == ConfigReq)
{
- signed int x = l - 4;
+ int x = l - 4;
u8 *o = (p + 4);
+ u8 *response = 0;
- log(3, session[s].ip, s, t, "LCP: ConfigReq (%d bytes)...\n", l);
- dumplcp(p, l);
+ LOG(3, s, t, "LCP: ConfigReq (%d bytes)...\n", l);
+ if (config->debug > 3) dumplcp(p, l);
while (x > 2)
{
int type = o[0];
int length = o[1];
- if (length == 0 || type == 0) break;
+
+ if (length == 0 || type == 0 || x < length) break;
switch (type)
{
case 1: // Maximum-Receive-Unit
session[s].mru = ntohs(*(u16 *)(o + 2));
break;
- case 2: // asyncmap
- log_hex(2, "PPP LCP Packet", p, l);
- log(2, 0, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_lcp_types[(int)*p], ntohs( ((u16 *) p)[1]) );
+
+ case 2: // Async-Control-Character-Map
+ if (!ntohl(*(u32 *)(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;
+ *((u16 *) (response + 2)) = htons(q - response); // LCP header length
break;
+
case 3: // Authentication-Protocol
{
int proto = ntohs(*(u16 *)(o + 2));
- if (proto == 0xC223)
+ char proto_name[] = "0x0000";
+ if (proto == PPPPAP)
+ break;
+
+ if (response && *response != ConfigNak) // rej already queued
+ break;
+
+ if (proto == PPPCHAP)
+ strcpy(proto_name, "CHAP");
+ else
+ sprintf(proto_name, "%#4.4x", proto);
+
+ LOG(2, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name);
+
+ if (!response)
{
- log(2, session[s].ip, s, t, " Remote end is trying to do CHAP. Rejecting it.\n");
-
- if (!q)
- {
- q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
- if (!q) {
- log(2, session[s].ip, s, t, " Failed to send packet.\n");
- break;
- }
- *q++ = ConfigNak;
- }
- memcpy(q, o, length);
- *(u16 *)(q += 2) = htons(0xC023); // NAK -> Use PAP instead
- q += length;
+ q = response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP);
+ if (!q) break;
+ *q = ConfigNak;
+ q += 4;
}
- break;
+
+ if ((q - b + length) > sizeof(b))
+ {
+ LOG(2, s, t, "LCP overflow for %s ConfigNak.\n", proto_name);
+ break;
+ }
+
+ memcpy(q, o, length);
+ *(u16 *)(q += 2) = htons(PPPPAP); // NAK -> Use PAP instead
+ q += length;
+ *((u16 *) (response + 2)) = htons(q - response);
}
+ break;
+
case 5: // Magic-Number
- {
- magicno = ntohl(*(u32 *)(o + 2));
- break;
- }
+ magicno = ntohl(*(u32 *)(o + 2));
+ break;
+
case 4: // Quality-Protocol
case 7: // Protocol-Field-Compression
case 8: // Address-And-Control-Field-Compression
+ 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;
- case 13: // CallBack option for LCP extention of win2000/routers L2TP client
- case 17:
- case 18:
- {
- // Reject LCP CallBack
- log(2, session[s].ip, s, t, " PPP LCP Option type %d, len=%d\n", type, length);
- memcpy(p + 4, o, length);
- *(u16 *)(p + 2) = htons(length + 4);
- *p = ConfigRej;
- q = makeppp(b,sizeof(b), p, length + 4, t, s, PPPLCP);
- tunnelsend(b, 12 + length + 4, t);
- return;
}
- default:
- // Reject Unknown LCP Option to stop to send it again
- log(2, session[s].ip, s, t, " Unknown PPP LCP Option type %d\n", type);
- memcpy(p + 4, o, length);
- *(u16 *)(p + 2) = htons(length + 4);
- *p = ConfigRej;
- q = makeppp(b,sizeof(b), p, length + 4, t, s, PPPLCP);
- tunnelsend(b, 12 + length + 4, t);
- return;
+ memcpy(q, o, length);
+ q += length;
+ *((u16 *) (response + 2)) = htons(q - response); // LCP header length
}
x -= length;
o += length;
}
- if (!q)
+ if (!response)
{
// Send back a ConfigAck
- log(3, session[s].ip, s, t, "ConfigReq accepted, sending as Ack\n");
- q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
- if (!q) {
- log(3, session[s].ip, s, t, " failed to create packet.\n");
- return;
- }
+ q = response = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
+ if (!q) return;
*q = ConfigAck;
- tunnelsend(b, l + (q - b), t);
- // For win2k L2TP clients, LCP should be initiated by the LNS
- if (magicno) initlcp(t, s);
- }
- else
- {
- // Already built a ConfigNak... send it
- log(3, session[s].ip, s, t, "Sending ConfigNak\n");
- tunnelsend(b, l + (q - b), t);
}
- if (!(session[s].flags & SESSIONLCPACK))
+ LOG(3, s, t, "Sending %s\n", ppp_lcp_types[*response]);
+ tunnelsend(b, l + (q - b), t);
+
+ if (!(session[s].flags & SF_LCP_ACKED))
initlcp(t, s);
}
else if (*p == ConfigNak)
{
- log(1, session[s].ip, s, t, "Remote end sent a ConfigNak. Ignoring\n");
- dumplcp(p, l);
+ LOG(1, s, t, "Remote end sent a ConfigNak. Ignoring\n");
+ if (config->debug > 3) dumplcp(p, l);
return ;
}
else if (*p == TerminateReq)
{
- *p = TerminateAck; // close
+ LOG(3, s, t, "LCP: Received TerminateReq. Sending TerminateAck\n");
+ *p = TerminateAck; // close
q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
- if (!q) {
- log(3, session[s].ip, s, t, "Failed to create PPP packet in processlcp.\n");
- return;
- }
- log(3, session[s].ip, s, t, "LCP: Received TerminateReq. Sending TerminateAck\n");
- sessionshutdown(s, "Remote end closed connection.");
+ if (!q) return;
tunnelsend(b, l + (q - b), t); // send it
+ sessionshutdown(s, "Remote end closed connection.");
}
else if (*p == TerminateAck)
{
}
else if (*p == EchoReq)
{
- *p = EchoReply; // reply
+ LOG(5, s, t, "LCP: Received EchoReq. Sending EchoReply\n");
+ *p = EchoReply; // reply
*(u32 *) (p + 4) = htonl(session[s].magic); // our magic number
q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
- if (!q) {
- log(3, session[s].ip, s, t, " failed to send EchoReply.\n");
- return;
- }
- log(5, session[s].ip, s, t, "LCP: Received EchoReq. Sending EchoReply\n");
+ if (!q) return;
tunnelsend(b, l + (q - b), t); // send it
}
else if (*p == EchoReply)
*p = CodeRej;
if (l > MAXCONTROL)
{
- log(1, 0, s, t, "Truncated Ident Packet (length=%d) to 1400 bytes\n", l);
+ 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)
- {
- log(3, session[s].ip, s, t, "Failed to create IdentRej.\n");
- return;
- }
- log_hex(5, "LCPIdentRej", q, l + 4);
+ if (!q) return;
+ LOG_HEX(5, "LCPIdentRej", q, l + 4);
tunnelsend(b, 12 + 4 + l, t);
}
else
{
- log(1, session[s].ip, s, t, "Unexpected LCP code %d\n", *p);
+ LOG(1, s, t, "Unexpected LCP code %d\n", *p);
STAT(tunnel_rx_errors);
return ;
}
}
+// find a PPP option, returns point to option, or 0 if not found
+static u8 *findppp(u8 *b, u8 mtype)
+{
+ u16 l = ntohs(*(u16 *) (b + 2));
+ if (l < 4)
+ return 0;
+ b += 4;
+ l -= 4;
+ while (l)
+ {
+ if (l < b[1] || !b[1])
+ return 0; // faulty
+ if (*b == mtype)
+ return b;
+ l -= b[1];
+ b += b[1];
+ }
+ return 0;
+}
+
// Process IPCP messages
-void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l)
+void processipcp(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
+ u16 hl;
CSTAT(call_processipcp);
- log_hex(5, "IPCP", p, l);
+ LOG_HEX(5, "IPCP", p, l);
if (l < 5)
{
- log(1, 0, s, t, "Short IPCP %d bytes\n", l);
+ LOG(1, s, t, "Short IPCP %d bytes\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
+ if ((hl = ntohs(*(u16 *) (p + 2))) > l)
+ {
+ LOG(1, s, t, "Length mismatch IPCP %u/%u\n", hl, l);
STAT(tunnel_rx_errors);
return ;
}
+ l = hl;
+
if (*p == ConfigAck)
{
// happy with our IPCP
u16 r = session[s].radius;
- if ((!r || radius[r].state == RADIUSIPCP) && !session[s].walled_garden) {
+ if ((!r || radius[r].state == RADIUSIPCP) && !session[s].walled_garden)
+ {
if (!r)
r = radiusnew(s);
if (r)
}
session[s].flags |= SF_IPCP_ACKED;
- log(3, session[s].ip, s, t, "IPCP Acked, session is now active\n");
+ LOG(3, s, t, "IPCP Acked, session is now active\n");
+
+ // clear LCP_ACKED/CCP_ACKED flag for possible fast renegotiaion for routers
+ session[s].flags &= ~(SF_LCP_ACKED|SF_CCP_ACKED);
+
return;
}
if (*p != ConfigReq)
{
- log(1, 0, s, t, "Unexpected IPCP code %d\n", *p);
- STAT(tunnel_rx_errors);
- return ;
- }
- log(4, session[s].ip, s, t, "IPCP ConfigReq received\n");
- if (ntohs(*(u16 *) (p + 2)) > l)
- {
- log(1, 0, s, t, "Length mismatch IPCP %d/%d\n", ntohs(*(u16 *) (p + 2)), l);
+ LOG(1, s, t, "Unexpected IPCP code %d\n", *p);
STAT(tunnel_rx_errors);
return ;
}
+ LOG(4, s, t, "IPCP ConfigReq received\n");
+
if (!session[s].ip)
{
- log(3, 0, s, t, "Waiting on radius reply\n");
- return ; // have to wait on RADIUS reply
+ LOG(3, s, t, "Waiting on radius reply\n");
+ return; // have to wait on RADIUS reply
}
// form a config reply quoting the IP in the session
{
u8 *i,
*q;
- l = ntohs(*(u16 *) (p + 2)); // We must use length from IPCP len field
q = p + 4;
i = p + l;
while (q < i && q[1])
u16 n = 4;
i = p + l;
if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP)))
- {
- log(2, 0, s, t, "Failed to send IPCP ConfigRej\n");
return;
- }
+
*q = ConfigRej;
p += 4;
while (p < i && p[1])
{
if (*p != 0x81 && *p != 0x83 && *p != 3)
{
- log(2, 0, s, t, "IPCP reject %d\n", *p);
+ LOG(2, s, t, "IPCP reject %d\n", *p);
memcpy(q + n, p, p[1]);
n += p[1];
}
p += p[1];
}
*(u16 *) (q + 2) = htons(n);
- log(4, session[s].ip, s, t, "Sending ConfigRej\n");
+ LOG(4, s, t, "Sending ConfigRej\n");
tunnelsend(b, n + (q - b), t); // send it
}
else
{
- log(4, session[s].ip, s, t, "Sending ConfigAck\n");
+ LOG(4, s, t, "Sending ConfigAck\n");
*p = ConfigAck;
if ((i = findppp(p, 0x81))) // Primary DNS address
{
{
*(u32 *) (i + 2) = htonl(session[s].dns1);
*p = ConfigNak;
- log(5, session[s].ip, s, t, " DNS1 = %s\n", inet_toa(session[s].dns1));
+ LOG(5, s, t, " DNS1 = %s\n",
+ fmtaddr(htonl(session[s].dns1), 0));
}
}
if ((i = findppp(p, 0x83))) // Secondary DNS address (TBA, is it)
{
*(u32 *) (i + 2) = htonl(session[s].dns2);
*p = ConfigNak;
- log(5, session[s].ip, s, t, " DNS2 = %s\n", inet_toa(session[s].dns1));
+ LOG(5, s, t, " DNS2 = %s\n",
+ fmtaddr(htonl(session[s].dns2), 0));
}
}
- i = findppp(p, 3); // IP address
+ i = findppp(p, 3); // IP address
if (!i || i[1] != 6)
{
- log(1, 0, s, t, "No IP in IPCP request\n");
+ LOG(1, s, t, "No IP in IPCP request\n");
STAT(tunnel_rx_errors);
return ;
}
{
*(u32 *) (i + 2) = htonl(session[s].ip);
*p = ConfigNak;
- log(4, session[s].ip, s, t, " No, a ConfigNak, client is requesting IP - sending %s\n",
- inet_toa(htonl(session[s].ip)));
+ 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)))
- {
- log(2, 0, s, t, " Failed to send IPCP packet.\n");
return;
- }
+
tunnelsend(b, l + (q - b), t); // send it
}
}
//
// 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, u8 * p, u16 l)
+void processipin(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
ipt ip;
-
CSTAT(call_processipin);
- log_hex(5, "IP", p, l);
+ LOG_HEX(5, "IP", p, l);
ip = ntohl(*(u32 *)(p + 12));
if (l > MAXETHER)
{
- log(1, ip, s, t, "IP packet too long %d\n", l);
+ LOG(1, s, t, "IP packet too long %d\n", l);
STAT(tunnel_rx_errors);
return ;
}
// no spoof (do sessionbyip to handled statically routed subnets)
if (ip != session[s].ip && sessionbyip(htonl(ip)) != s)
{
- log(5, ip, s, t, "Dropping packet with spoofed IP %s\n", inet_toa(htonl(ip)));
+ LOG(5, s, t, "Dropping packet with spoofed IP %s\n", fmtaddr(htonl(ip), 0));
return;
}
+ // run access-list if any
+ if (session[s].filter_in && !ip_filter(p, l, session[s].filter_in - 1))
+ return;
+
// Add on the tun header
p -= 4;
*(u32 *)p = htonl(0x00000800);
return;
}
- session[s].cin += l - 4;
- session[s].total_cin += l - 4;
- sess_count[s].cin += l - 4;
-
- session[s].pin++;
- eth_tx += l - 4;
-
- if (session[s].snoop_ip && session[s].snoop_port)
- {
- // Snooping this session, send it to ASIO
- snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
- }
- STAT(tun_tx_packets);
- INC_STAT(tun_tx_bytes, l);
-
if (session[s].tbf_in && config->cluster_iam_master) { // Are we throttled and a master?? actually handle the throttled packets.
tbf_queue_packet(session[s].tbf_in, p, l);
return;
if (tun_write(p, l) < 0)
{
STAT(tun_tx_errors);
- log(0, 0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+ LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
l, strerror(errno), tunfd, p);
+
+ return;
+ }
+
+ if (session[s].snoop_ip && session[s].snoop_port)
+ {
+ // Snooping this session
+ snoop_send_packet(p + 4, l - 4, session[s].snoop_ip, session[s].snoop_port);
}
+ session[s].cin += l - 4;
+ session[s].total_cin += l - 4;
+ sess_count[s].cin += l - 4;
+
+ session[s].pin++;
+ eth_tx += l - 4;
+
+ STAT(tun_tx_packets);
+ INC_STAT(tun_tx_bytes, l - 4);
}
//
//
void send_ipin(sessionidt s, u8 *buf, int len)
{
- log_hex(5, "IP in throttled", buf, len);
+ LOG_HEX(5, "IP in throttled", buf, len);
+
if (write(tunfd, buf, len) < 0)
{
STAT(tun_tx_errors);
- log(0, 0, 0, 0, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+ LOG(0, 0, 0, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
len, strerror(errno), tunfd, buf);
+
+ return;
+ }
+
+ if (session[s].snoop_ip && session[s].snoop_port)
+ {
+ // Snooping this session
+ snoop_send_packet(buf + 4, len - 4, session[s].snoop_ip, session[s].snoop_port);
}
// Increment packet counters
session[s].pin++;
eth_tx += len - 4;
+
+ STAT(tun_tx_packets);
+ INC_STAT(tun_tx_bytes, len - 4);
}
-// Process LCP messages
-void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l)
+// Process CCP messages
+void processccp(tunnelidt t, sessionidt s, u8 *p, u16 l)
{
+ u8 b[MAXCONTROL];
+ u8 *q;
CSTAT(call_processccp);
- log_hex(5, "CCP", p, l);
- if (l < 2 || (*p != ConfigReq && *p != TerminateReq))
- {
- log(1, 0, s, t, "Unexpecetd CCP request code %d\n", *p);
- STAT(tunnel_rx_errors);
- return ;
- }
- // reject
+ LOG_HEX(5, "CCP", p, l);
+ switch (l > 1 ? *p : 0)
{
- u8 b[MAXCONTROL];
- u8 *q;
- if (*p == ConfigReq)
+ case ConfigAck:
+ session[s].flags |= SF_CCP_ACKED;
+ return;
+
+ case ConfigReq:
+ if (l < 6) // accept no compression
{
- if (l < 6)
- {
- *p = ConfigAck; // accept no compression
- }
- else
- {
- *p = ConfigRej; // reject
- sendccp(t, s);
- }
+ *p = ConfigAck;
+ break;
}
+
+ // compression requested--reject
+ *p = ConfigRej;
+
+ // send CCP request for no compression for our end if not negotiated
+ if (!(session[s].flags & SF_CCP_ACKED))
+ initccp(t, s);
+
+ break;
+
+ case TerminateReq:
+ *p = TerminateAck;
+ break;
+
+ default:
+ if (l > 1)
+ LOG(1, s, t, "Unexpected CCP request code %d\n", *p);
else
- *p = TerminateAck; // close
- if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP)))
- {
- log(1,0,0,0, "Failed to send CCP packet.\n");
- return;
- }
- tunnelsend(b, l + (q - b), t); // send it
+ LOG(1, s, t, "Short CCP packet\n");
+
+ STAT(tunnel_rx_errors);
+ return;
}
+
+ if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP)))
+ return;
+
+ tunnelsend(b, l + (q - b), t); // send it
}
// send a CHAP PP packet
if (!r)
{
- log(1, 0, s, t, "No RADIUS to send challenge\n");
+ LOG(1, s, t, "No RADIUS to send challenge\n");
STAT(tunnel_tx_errors);
return ;
}
- log(1, 0, s, t, "Send CHAP challenge\n");
- { // new challenge
+ LOG(1, s, t, "Send CHAP challenge\n");
+ {
+ // new challenge
int n;
for (n = 0; n < 15; n++)
radius[r].auth[n] = rand();
}
- radius[r].chap = 1; // CHAP not PAP
+ radius[r].chap = 1; // CHAP not PAP
radius[r].id++;
if (radius[r].state != RADIUSCHAP)
radius[r].try = 0;
return ;
}
q = makeppp(b, sizeof(b), 0, 0, t, s, PPPCHAP);
- if (!q) {
- log(1, 0, s, t, "failed to send CHAP challenge.\n");
- return;
- }
- *q = 1; // challenhe
- q[1] = radius[r].id; // ID
- q[4] = 16; // length
- memcpy(q + 5, radius[r].auth, 16); // challenge
- strcpy(q + 21, hostname); // our name
+ if (!q) return;
+
+ *q = 1; // challenge
+ q[1] = radius[r].id; // ID
+ q[4] = 16; // length
+ memcpy(q + 5, radius[r].auth, 16); // challenge
+ strcpy(q + 21, hostname); // our name
*(u16 *) (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
-u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype)
+u8 *makeppp(u8 *b, int size, u8 *p, int l, tunnelidt t, sessionidt s, u16 mtype)
{
-
- if (size < 12)
- return NULL; // Need more space than this!!
+ 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;
+ }
*(u16 *) (b + 0) = htons(0x0002); // L2TP with no options
*(u16 *) (b + 2) = htons(tunnel[t].far); // tunnel
*(u16 *) (b + 4) = htons(session[s].far); // session
b += 6;
- if (mtype && !(session[s].l2tp_flags & SESSIONACFC))
+ if (mtype == PPPLCP || !(session[s].l2tp_flags & SESSIONACFC))
{
*(u16 *) b = htons(0xFF03); // HDLC header
b += 2;
b += 2;
}
- if (l + 12 > size) {
- log(3,0,0,0, "Would have overflowed the buffer in makeppp: size %d, len %d.\n", size, l);
- return NULL; // Run out of room to hold the packet!
+ 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;
}
+
if (p && l)
memcpy(b, p, l);
- return b;
-}
-// find a PPP option, returns point to option, or 0 if not found
-u8 *findppp(u8 * b, u8 mtype)
-{
- u16 l = ntohs(*(u16 *) (b + 2));
- if (l < 4)
- return 0;
- b += 4;
- l -= 4;
- while (l)
- {
- if (l < b[1] || !b[1])
- return 0; // faulty
- if (*b == mtype)
- return b;
- l -= b[1];
- b += b[1];
- }
- return 0;
+ return b;
}
-// Send initial LCP ConfigReq
+// Send initial LCP ConfigReq for PAP, set magic no.
void initlcp(tunnelidt t, sessionidt s)
{
- char b[500] = {0}, *q;
+ char b[500], *q;
- q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP);
- if (!q) {
- log(1, 0, s, t, "Failed to send LCP ConfigReq.\n");
+ if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP)))
return;
- }
- log(4, 0, s, t, "Sending LCP ConfigReq for PAP\n");
+
+ LOG(4, s, t, "Sending LCP ConfigReq for PAP\n");
*q = ConfigReq;
*(u8 *)(q + 1) = (time_now % 255) + 1; // ID
- *(u16 *)(q + 2) = htons(8); // Length
- *(u8 *)(q + 4) = 3;
- *(u8 *)(q + 5) = 4;
- *(u16 *)(q + 6) = htons(0xC023); // PAP
- tunnelsend(b, 12 + 8, t);
+ *(u16 *)(q + 2) = htons(14); // Length
+ *(u8 *)(q + 4) = 5;
+ *(u8 *)(q + 5) = 6;
+ *(u32 *)(q + 6) = htonl(session[s].magic);
+ *(u8 *)(q + 10) = 3;
+ *(u8 *)(q + 11) = 4;
+ *(u16 *)(q + 12) = htons(PPPPAP); // PAP
+
+ LOG_HEX(5, "PPPLCP", q, 14);
+ tunnelsend(b, (q - b) + 14, t);
}
-// Send CCP reply
-void sendccp(tunnelidt t, sessionidt s)
+// Send CCP request for no compression
+static void initccp(tunnelidt t, sessionidt s)
{
- char *q, b[500] = {0};
+ char b[500], *q;
- q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP);
+ if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP)))
+ return;
+
+ LOG(4, s, t, "Sending CCP ConfigReq for no compression\n");
*q = ConfigReq;
*(u8 *)(q + 1) = (time_now % 255) + 1; // ID
*(u16 *)(q + 2) = htons(4); // Length
- log_hex(5, "PPPCCP", q, 4);
+
+ LOG_HEX(5, "PPPCCP", q, 4);
tunnelsend(b, (q - b) + 4 , t);
}
-
projects / l2tpns.git / blobdiff