// L2TPNS PPP Stuff
-char const *cvs_id_ppp = "$Id: ppp.c,v 1.79 2005/08/31 12:41:09 bodea Exp $";
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.84 2005/09/16 13:20:39 bodea Exp $";
#include <stdio.h>
#include <string.h>
else if (length == 5)
{
int proto = ntohs(*(uint16_t *)(o + 2));
- int algo = *(uint8_t *)(o + 4);
+ 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");
}
change_state(s, ccp, Dead);
}
-static uint8_t *ppp_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+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)
return queued + option[1];
}
-static uint8_t *ppp_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
+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)
{
if (*nak_sent < config->ppp_max_failure) // reject queued
return queued;
- return ppp_rej(s, buf, blen, mtype, response, 0, packet, option);
+ return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
}
if (!*response)
{
if (*nak_sent >= config->ppp_max_failure)
- return ppp_rej(s, buf, blen, mtype, response, 0, packet, option);
+ 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 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 > 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(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
{
break;
LOG(3, s, t, " Remote requesting asyncmap. Rejecting.\n");
- q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap));
break;
case 3: // Authentication-Protocol
alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authprefer);
if (alen < 2) break; // paranoia
- q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+ 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)
{
// alternate type
alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authtypes & ~config->radius_authprefer);
if (alen < 2) break;
- q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+ q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
}
break;
default: // Reject any unknown options
LOG(3, s, t, " Rejecting unknown PPP LCP option %d\n", type);
- q = ppp_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
}
x -= length;
o += length;
case 1: // Maximum-Receive-Unit
if (*p == ConfigNak)
{
- session[s].mru = ntohs(*(uint16_t *)(o + 2));
- LOG(3, s, t, " Remote requested MRU of %u\n", session[s].mru);
+ 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
{
- session[s].mru = 0;
+ sess_local[s].ppp_mru = 0;
LOG(3, s, t, " Remote rejected MRU negotiation\n");
}
}
else if (*p != CodeRej)
{
- int code = *p;
- int mru = session[s].mru;
- if (!mru)
- mru = DEFAULT_MRU;
-
- if (l > mru) l = mru;
-
- *p = CodeRej;
- q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP);
- if (!q) return;
-
- LOG(2, s, t, "Unexpected LCP code %s\n", ppp_code(code));
- LOG(3, s, t, "LCP: send %s\n", ppp_code(*q));
- if (config->debug > 3) dumplcp(q, l);
-
- tunnelsend(b, l + (q - b), t);
+ ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b));
}
}
if (memcmp(o + 2, &addr, (sizeof addr)))
{
uint8_t *oq = q;
- q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ 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);
addr = htonl(session[s].dns1);
if (memcmp(o + 2, &addr, (sizeof addr)))
{
- q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
if (!q) return;
}
addr = htonl(session[s].dns1);
if (memcmp(o + 2, &addr, sizeof(addr)))
{
- q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
if (!q) return;
}
default:
LOG(2, s, t, " Rejecting PPP IPCP Option type %d\n", *o);
- q = ppp_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
if (!q) return;
}
}
else if (*p != CodeRej)
{
- int code = *p;
- int mru = session[s].mru;
- if (!mru)
- mru = DEFAULT_MRU;
-
- if (l > mru) l = mru;
-
- *p = CodeRej;
- q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP);
- if (!q) return;
-
- LOG(2, s, t, "Unexpected IPCP code %s\n", ppp_code(code));
- LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q));
- tunnelsend(b, l + (q - b), t);
+ ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b));
}
}
LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p));
- if (!config->ipv6_prefix.s6_addr[0])
- {
- LOG(2, s, t, "IPV6CP: %s rejected (not configured)\n", ppp_code(*p));
- *p = ProtocolRej;
- q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP);
- if (!q) return;
- tunnelsend(b, l + (q - b), t);
- return;
- }
-
if (!session[s].ip)
{
LOG(3, s, t, "IPV6CP: no IPv4 address (IPCP in state %s)\n", ppp_state(session[s].ppp.ipcp));
if (memcmp(o + 2, ident, sizeof(ident)))
{
- q = ppp_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
+ q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
if (!q) return;
}
default:
LOG(2, s, t, " Rejecting PPP IPV6CP Option type %d\n", *o);
- q = ppp_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
if (!q) return;
}
}
else if (*p != CodeRej)
{
- int code = *p;
- int mru = session[s].mru;
- if (!mru)
- mru = DEFAULT_MRU;
-
- if (l > mru) l = mru;
-
- *p = CodeRej;
- q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP);
- if (!q) return;
-
- LOG(2, s, t, "Unexpected IPV6CP code %s\n", ppp_code(code));
- LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q));
- tunnelsend(b, l + (q - b), t);
+ ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b));
}
}
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)
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);
}
else if (*p != CodeRej)
{
- int code = *p;
- int mru = session[s].mru;
- if (!mru)
- mru = DEFAULT_MRU;
-
- if (l > mru) l = mru;
-
- *p = CodeRej;
- q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP);
- if (!q) return;
-
- LOG(2, s, t, "Unexpected CCP code %s\n", ppp_code(code));
- LOG(3, s, t, "CCP: send %s\n", ppp_code(*q));
- tunnelsend(b, l + (q - b), t);
+ ppp_code_rej(s, t, PPPCCP, "CCP", p, l, b, sizeof(b));
}
}
l = q;
*l++ = ConfigReq;
- *l++ = (time_now % 255) + 1; // ID
+ *l++ = ++sess_local[s].lcp_ident; // ID
l += 2; //Save space for length
- if (session[s].mru)
+ if (sess_local[s].ppp_mru)
{
*l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
- *(uint16_t *) l = htons(session[s].mru); l += 2;
+ *(uint16_t *) l = htons(sess_local[s].ppp_mru); l += 2;
}
if (authtype)
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);