1839 lines
41 KiB
C
1839 lines
41 KiB
C
// L2TPNS PPP Stuff
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char const *cvs_id_ppp = "$Id: ppp.c,v 1.67 2005-08-10 08:59:23 bodea Exp $";
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <errno.h>
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#include <stdlib.h>
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#include "l2tpns.h"
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#include "constants.h"
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#include "plugin.h"
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#include "util.h"
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#include "tbf.h"
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#include "cluster.h"
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extern tunnelt *tunnel;
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extern sessiont *session;
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extern radiust *radius;
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extern int tunfd;
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extern char hostname[];
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extern uint32_t eth_tx;
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extern time_t time_now;
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extern configt *config;
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static int add_lcp_auth(uint8_t *b, int size, int authtype);
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// Process PAP messages
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void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
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{
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char user[MAXUSER];
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char pass[MAXPASS];
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uint16_t hl;
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uint16_t r;
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CSTAT(processpap);
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LOG_HEX(5, "PAP", p, l);
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if (l < 4)
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{
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LOG(1, s, t, "Short PAP %u bytes\n", l);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "Short PAP packet.", 3, 0);
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return;
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}
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if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
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{
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LOG(1, s, t, "Length mismatch PAP %u/%u\n", hl, l);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "PAP length mismatch.", 3, 0);
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return;
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}
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l = hl;
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if (*p != 1)
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{
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LOG(1, s, t, "Unexpected PAP code %d\n", *p);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "Unexpected PAP code.", 3, 0);
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return;
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}
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if (session[s].ppp.phase != Authenticate)
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{
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LOG(2, s, t, "PAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
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return;
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}
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{
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uint8_t *b = p;
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b += 4;
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user[0] = pass[0] = 0;
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if (*b && *b < sizeof(user))
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{
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memcpy(user, b + 1, *b);
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user[*b] = 0;
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b += 1 + *b;
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if (*b && *b < sizeof(pass))
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{
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memcpy(pass, b + 1, *b);
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pass[*b] = 0;
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}
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}
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LOG(3, s, t, "PAP login %s/%s\n", user, pass);
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}
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r = radiusnew(s);
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if (session[s].ip || !r)
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{
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// respond now, either no RADIUS available or already authenticated
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uint8_t b[MAXCONTROL];
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uint8_t id = p[1];
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uint8_t *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP);
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if (!p) return;
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if (session[s].ip)
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*p = 2; // ACK
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else
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*p = 3; // cant authorise
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p[1] = id;
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*(uint16_t *) (p + 2) = htons(5); // length
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p[4] = 0; // no message
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tunnelsend(b, 5 + (p - b), t); // send it
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if (session[s].ip)
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{
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LOG(3, s, t, "Already an IP allocated: %s (%d)\n",
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fmtaddr(htonl(session[s].ip), 0), session[s].ip_pool_index);
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}
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else
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{
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LOG(1, s, t, "No RADIUS session available to authenticate session...\n");
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sessionshutdown(s, "No free RADIUS sessions.", 4, 0);
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}
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}
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else
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{
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// Run PRE_AUTH plugins
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struct param_pre_auth packet = { &tunnel[t], &session[s], strdup(user), strdup(pass), PPPPAP, 1 };
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run_plugins(PLUGIN_PRE_AUTH, &packet);
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if (!packet.continue_auth)
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{
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LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
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if (packet.username) free(packet.username);
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if (packet.password) free(packet.password);
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return;
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}
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strncpy(session[s].user, packet.username, sizeof(session[s].user) - 1);
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strncpy(radius[r].pass, packet.password, sizeof(radius[r].pass) - 1);
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free(packet.username);
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free(packet.password);
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radius[r].id = p[1];
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LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);
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radiussend(r, RADIUSAUTH);
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}
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}
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// Process CHAP messages
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void processchap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
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{
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uint16_t r;
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uint16_t hl;
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CSTAT(processchap);
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LOG_HEX(5, "CHAP", p, l);
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r = sess_local[s].radius;
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if (!r)
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{
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LOG(1, s, t, "Unexpected CHAP message\n");
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STAT(tunnel_rx_errors);
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return;
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}
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if (l < 4)
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{
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LOG(1, s, t, "Short CHAP %u bytes\n", l);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "Short CHAP packet.", 3, 0);
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return;
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}
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if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
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{
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LOG(1, s, t, "Length mismatch CHAP %u/%u\n", hl, l);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "CHAP length mismatch.", 3, 0);
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return;
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}
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l = hl;
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if (*p != 2)
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{
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LOG(1, s, t, "Unexpected CHAP response code %d\n", *p);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "CHAP length mismatch.", 3, 0);
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return;
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}
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if (session[s].ppp.phase != Authenticate)
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{
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LOG(2, s, t, "CHAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
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return;
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}
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if (p[1] != radius[r].id)
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{
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LOG(1, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "Unexpected CHAP response ID.", 3, 0);
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return;
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}
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if (l < 5 || p[4] != 16)
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{
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LOG(1, s, t, "Bad CHAP response length %d\n", l < 5 ? -1 : p[4]);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "Bad CHAP response length.", 3, 0);
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return;
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}
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l -= 5;
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p += 5;
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if (l < 16 || l - 16 >= sizeof(session[s].user))
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{
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LOG(1, s, t, "CHAP user too long %d\n", l - 16);
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STAT(tunnel_rx_errors);
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sessionshutdown(s, "CHAP username too long.", 3, 0);
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return;
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}
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// Run PRE_AUTH plugins
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{
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struct param_pre_auth packet = { &tunnel[t], &session[s], NULL, NULL, PPPCHAP, 1 };
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packet.password = calloc(17, 1);
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memcpy(packet.password, p, 16);
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p += 16;
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l -= 16;
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packet.username = calloc(l + 1, 1);
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memcpy(packet.username, p, l);
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run_plugins(PLUGIN_PRE_AUTH, &packet);
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if (!packet.continue_auth)
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{
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LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
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if (packet.username) free(packet.username);
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if (packet.password) free(packet.password);
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return;
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}
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strncpy(session[s].user, packet.username, sizeof(session[s].user) - 1);
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memcpy(radius[r].pass, packet.password, 16);
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free(packet.username);
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free(packet.password);
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}
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radius[r].chap = 1;
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LOG(3, s, t, "CHAP login %s\n", session[s].user);
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radiussend(r, RADIUSAUTH);
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}
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static void dumplcp(uint8_t *p, int l)
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{
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int x = l - 4;
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uint8_t *o = (p + 4);
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LOG_HEX(5, "PPP LCP Packet", p, l);
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LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_code((int)*p), ntohs( ((uint16_t *) p)[1]) );
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LOG(4, 0, 0, "Length: %d\n", l);
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if (*p != ConfigReq && *p != ConfigRej && *p != ConfigAck)
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return;
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while (x > 2)
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{
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int type = o[0];
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int length = o[1];
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if (length < 2)
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{
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LOG(4, 0, 0, " Option length is %d...\n", length);
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break;
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}
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if (type == 0)
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{
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LOG(4, 0, 0, " Option type is 0...\n");
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x -= length;
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o += length;
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continue;
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}
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switch (type)
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{
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case 1: // Maximum-Receive-Unit
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if (length == 4)
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LOG(4, 0, 0, " %s %d\n", ppp_lcp_option(type), ntohs(*(uint16_t *)(o + 2)));
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else
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LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
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break;
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case 2: // Async-Control-Character-Map
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if (length == 6)
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{
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uint32_t asyncmap = ntohl(*(uint32_t *)(o + 2));
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LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), asyncmap);
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}
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else
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LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
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break;
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case 3: // Authentication-Protocol
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if (length == 4)
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{
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int proto = ntohs(*(uint16_t *)(o + 2));
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LOG(4, 0, 0, " %s 0x%x (%s)\n", ppp_lcp_option(type), proto,
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proto == PPPPAP ? "PAP" : "UNSUPPORTED");
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}
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else if (length == 5)
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{
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int proto = ntohs(*(uint16_t *)(o + 2));
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int algo = *(uint8_t *)(o + 4);
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LOG(4, 0, 0, " %s 0x%x 0x%x (%s)\n", ppp_lcp_option(type), proto, algo,
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(proto == PPPCHAP && algo == 5) ? "CHAP MD5" : "UNSUPPORTED");
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}
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else
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LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
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break;
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case 4: // Quality-Protocol
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{
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uint32_t qp = ntohl(*(uint32_t *)(o + 2));
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LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), qp);
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}
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break;
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case 5: // Magic-Number
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if (length == 6)
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{
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uint32_t magicno = ntohl(*(uint32_t *)(o + 2));
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LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), magicno);
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}
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else
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LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
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break;
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case 7: // Protocol-Field-Compression
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case 8: // Address-And-Control-Field-Compression
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LOG(4, 0, 0, " %s\n", ppp_lcp_option(type));
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break;
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default:
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LOG(2, 0, 0, " Unknown PPP LCP Option type %d\n", type);
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break;
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}
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x -= length;
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o += length;
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}
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}
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void lcp_open(tunnelidt t, sessionidt s)
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{
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// transition to Authentication or Network phase:
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session[s].ppp.phase = sess_local[s].lcp_authtype ? Authenticate : Network;
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// LCP now Opened
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change_state(s, lcp, Opened);
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if (session[s].ppp.phase == Authenticate)
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{
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if (sess_local[s].lcp_authtype == AUTHCHAP)
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sendchap(t, s);
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}
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else
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{
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// This-Layer-Up
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sendipcp(t, s);
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change_state(s, ipcp, RequestSent);
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// move to passive state for IPv6 (if configured), CCP
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if (config->ipv6_prefix.s6_addr[0])
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change_state(s, ipv6cp, Stopped);
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else
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change_state(s, ipv6cp, Closed);
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change_state(s, ccp, Stopped);
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}
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}
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static void lcp_restart(sessionidt s)
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{
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session[s].ppp.phase = Establish;
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// This-Layer-Down
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change_state(s, ipcp, Dead);
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change_state(s, ipv6cp, Dead);
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change_state(s, ccp, Dead);
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}
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static uint8_t *ppp_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
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uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option)
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{
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if (!*response || **response != ConfigRej)
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{
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queued = *response = makeppp(buf, blen, packet, 2, session[s].tunnel, s, mtype);
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if (!queued)
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return 0;
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*queued = ConfigRej;
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queued += 4;
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}
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if ((queued - buf + option[1]) > blen)
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{
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LOG(2, s, session[s].tunnel, "PPP overflow for ConfigRej (proto %u, option %u).\n", mtype, *option);
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return 0;
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}
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memcpy(queued, option, option[1]);
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return queued + option[1];
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}
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static uint8_t *ppp_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
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uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option,
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uint8_t *value, size_t vlen)
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{
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int *nak_sent;
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switch (mtype)
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{
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case PPPLCP: nak_sent = &sess_local[s].lcp.nak_sent; break;
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case PPPIPCP: nak_sent = &sess_local[s].ipcp.nak_sent; break;
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case PPPIPV6CP: nak_sent = &sess_local[s].ipv6cp.nak_sent; break;
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default: return 0; // ?
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}
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if (*response && **response != ConfigNak)
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{
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if (*nak_sent < config->ppp_max_failure) // reject queued
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return queued;
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return ppp_rej(s, buf, blen, mtype, response, 0, packet, option);
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}
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if (!*response)
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{
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if (*nak_sent >= config->ppp_max_failure)
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return ppp_rej(s, buf, blen, mtype, response, 0, packet, option);
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queued = *response = makeppp(buf, blen, packet, 2, session[s].tunnel, s, mtype);
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if (!queued)
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return 0;
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*nak_sent++;
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*queued = ConfigNak;
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queued += 4;
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}
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if ((queued - buf + vlen + 2) > blen)
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{
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LOG(2, s, session[s].tunnel, "PPP overflow for ConfigNak (proto %u, option %u).\n", mtype, *option);
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return 0;
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}
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*queued++ = *option;
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*queued++ = vlen + 2;
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memcpy(queued, value, vlen);
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return queued + vlen;
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}
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// Process LCP messages
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void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
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{
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uint8_t b[MAXCONTROL];
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uint8_t *q = NULL;
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uint32_t magicno = 0;
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uint16_t hl;
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CSTAT(processlcp);
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LOG_HEX(5, "LCP", p, l);
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if (l < 4)
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{
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LOG(1, s, t, "Short LCP %d bytes\n", l);
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STAT(tunnel_rx_errors);
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return ;
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}
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if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
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{
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LOG(1, s, t, "Length mismatch LCP %u/%u\n", hl, l);
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STAT(tunnel_rx_errors);
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return ;
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}
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l = hl;
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if (session[s].die) // going down...
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return;
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if (*p == ConfigAck)
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{
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int x = l - 4;
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uint8_t *o = (p + 4);
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int authtype = 0;
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LOG(3, s, t, "LCP: ConfigAck (%d bytes)...\n", l);
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if (config->debug > 3) dumplcp(p, l);
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while (x > 2)
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{
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int type = o[0];
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int length = o[1];
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if (length == 0 || type == 0 || x < length) break;
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switch (type)
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{
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case 3: // Authentication-Protocol
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{
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int proto = ntohs(*(uint16_t *)(o + 2));
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if (proto == PPPPAP)
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authtype = AUTHPAP;
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else if (proto == PPPCHAP && *(o + 4) == 5)
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authtype = AUTHCHAP;
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}
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break;
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}
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x -= length;
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|
o += length;
|
|
}
|
|
|
|
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, sess_local[s].lcp_authtype);
|
|
change_state(s, lcp, RequestSent);
|
|
break;
|
|
|
|
case AckSent:
|
|
lcp_open(t, s);
|
|
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;
|
|
static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero
|
|
static uint8_t authproto[5];
|
|
|
|
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 || x < length) break;
|
|
switch (type)
|
|
{
|
|
case 1: // Maximum-Receive-Unit
|
|
session[s].mru = ntohs(*(uint16_t *)(o + 2));
|
|
break;
|
|
|
|
case 2: // Async-Control-Character-Map
|
|
if (!ntohl(*(uint32_t *)(o + 2))) // all bits zero is OK
|
|
break;
|
|
|
|
LOG(2, s, t, " Remote requesting asyncmap. Rejecting.\n");
|
|
q = ppp_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";
|
|
int alen;
|
|
|
|
if (proto == PPPPAP)
|
|
{
|
|
if (config->radius_authtypes & AUTHPAP)
|
|
{
|
|
sess_local[s].lcp_authtype = AUTHPAP;
|
|
break;
|
|
}
|
|
|
|
strcpy(proto_name, "PAP");
|
|
}
|
|
else if (proto == PPPCHAP)
|
|
{
|
|
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);
|
|
|
|
LOG(2, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name);
|
|
|
|
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);
|
|
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);
|
|
}
|
|
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 5: // Magic-Number
|
|
magicno = ntohl(*(uint32_t *)(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);
|
|
q = ppp_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
|
|
}
|
|
x -= length;
|
|
o += length;
|
|
}
|
|
|
|
if (response)
|
|
{
|
|
l = q - response; // LCP packet length
|
|
*((uint16_t *) (response + 2)) = htons(l); // update header
|
|
}
|
|
else
|
|
{
|
|
// Send packet back as ConfigAck
|
|
response = makeppp(b, sizeof(b), p, l, t, s, PPPLCP);
|
|
if (!response) return;
|
|
*response = ConfigAck;
|
|
}
|
|
|
|
switch (session[s].ppp.lcp)
|
|
{
|
|
case Closed:
|
|
response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP);
|
|
if (!response) return;
|
|
*response = TerminateAck;
|
|
*((uint16_t *) (response + 2)) = htons(l = 4);
|
|
break;
|
|
|
|
case Stopped:
|
|
initialise_restart_count(s, lcp);
|
|
sendlcp(s, t, sess_local[s].lcp_authtype);
|
|
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(t, s);
|
|
|
|
break;
|
|
|
|
case Opened:
|
|
lcp_restart(s);
|
|
sendlcp(s, t, sess_local[s].lcp_authtype);
|
|
/* 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: Sending %s\n", ppp_code(*response));
|
|
tunnelsend(b, l + (response - b), t);
|
|
}
|
|
else if (*p == ConfigNak)
|
|
{
|
|
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];
|
|
int length = o[1];
|
|
|
|
if (length == 0 || type == 0 || x < length) break;
|
|
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);
|
|
break;
|
|
|
|
case 3: // Authentication-Protocol
|
|
if (authtype > 0)
|
|
break;
|
|
|
|
{
|
|
int proto = ntohs(*(uint16_t *)(o + 2));
|
|
if (proto == PPPPAP)
|
|
{
|
|
authtype = config->radius_authtypes & AUTHPAP;
|
|
LOG(3, s, t, " Remote requested PAP authentication...%sing\n",
|
|
authtype ? "accept" : "reject");
|
|
}
|
|
else if (proto == PPPCHAP && *(o + 4) == 5)
|
|
{
|
|
authtype = config->radius_authtypes & AUTHCHAP;
|
|
LOG(3, s, t, " Remote requested CHAP authentication...%sing\n",
|
|
authtype ? "accept" : "reject");
|
|
}
|
|
else
|
|
{
|
|
LOG(3, s, t, " Rejecting unsupported authentication %#4x\n",
|
|
proto);
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
default:
|
|
LOG(2, s, t, " Remote NAKed LCP type %u?\n", type);
|
|
break;
|
|
}
|
|
x -= length;
|
|
o += length;
|
|
}
|
|
|
|
if (!authtype)
|
|
{
|
|
sessionshutdown(s, "Unsupported authentication.", 3, 0);
|
|
return;
|
|
}
|
|
|
|
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, t, s, PPPLCP);
|
|
if (!response) return;
|
|
*response = TerminateAck;
|
|
*((uint16_t *) (response + 2)) = htons(l = 4);
|
|
tunnelsend(b, l + (response - b), t);
|
|
}
|
|
break;
|
|
|
|
case RequestSent:
|
|
case AckSent:
|
|
initialise_restart_count(s, lcp);
|
|
sendlcp(s, t, sess_local[s].lcp_authtype);
|
|
break;
|
|
|
|
case AckReceived:
|
|
LOG(2, s, t, "LCP: ConfigNak in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
|
|
sendlcp(s, t, sess_local[s].lcp_authtype);
|
|
break;
|
|
|
|
case Opened:
|
|
lcp_restart(s);
|
|
sendlcp(s, t, sess_local[s].lcp_authtype);
|
|
break;
|
|
|
|
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);
|
|
if (!q) return;
|
|
tunnelsend(b, l + (q - b), t); // send it
|
|
sessionshutdown(s, "Remote end closed connection.", 3, 0);
|
|
}
|
|
else if (*p == TerminateAck)
|
|
{
|
|
sessionshutdown(s, "Connection closed.", 3, 0);
|
|
}
|
|
else if (*p == ProtocolRej)
|
|
{
|
|
if (*(uint16_t *) (p+4) == htons(PPPIPV6CP))
|
|
{
|
|
LOG(3, s, t, "IPv6 rejected\n");
|
|
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);
|
|
}
|
|
}
|
|
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);
|
|
if (!q) return;
|
|
tunnelsend(b, l + (q - b), t); // send it
|
|
}
|
|
else if (*p == EchoReply)
|
|
{
|
|
// Ignore it, last_packet time is set earlier than this.
|
|
}
|
|
else
|
|
{
|
|
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, t, s, PPPLCP);
|
|
if (!q) return;
|
|
|
|
LOG(3, s, t, "Unexpected LCP code %s\n", ppp_code(code));
|
|
tunnelsend(b, l + (q - b), t);
|
|
}
|
|
}
|
|
|
|
static void ipcp_open(tunnelidt t, sessionidt s)
|
|
{
|
|
LOG(3, s, t, "IPCP: Opened, session is now active\n");
|
|
|
|
change_state(s, ipcp, Opened);
|
|
|
|
if (!session[s].walled_garden)
|
|
{
|
|
uint16_t r = radiusnew(s);
|
|
if (r)
|
|
radiussend(r, RADIUSSTART); // send radius start
|
|
}
|
|
|
|
// start IPv6 if configured and still in passive state
|
|
if (session[s].ppp.ipv6cp == Stopped)
|
|
{
|
|
sendipv6cp(t, s);
|
|
change_state(s, ipv6cp, RequestSent);
|
|
}
|
|
}
|
|
|
|
// Process IPCP messages
|
|
void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
|
|
{
|
|
uint8_t b[MAXCONTROL];
|
|
uint8_t *q = 0;
|
|
uint16_t hl;
|
|
|
|
CSTAT(processipcp);
|
|
|
|
LOG_HEX(5, "IPCP", p, l);
|
|
if (l < 5)
|
|
{
|
|
LOG(1, s, t, "Short IPCP %d bytes\n", l);
|
|
STAT(tunnel_rx_errors);
|
|
return ;
|
|
}
|
|
|
|
if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
|
|
{
|
|
LOG(1, s, t, "Length mismatch IPCP %u/%u\n", hl, l);
|
|
STAT(tunnel_rx_errors);
|
|
return ;
|
|
}
|
|
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;
|
|
}
|
|
|
|
if (*p == ConfigAck)
|
|
{
|
|
switch (session[s].ppp.ipcp)
|
|
{
|
|
case RequestSent:
|
|
initialise_restart_count(s, ipcp);
|
|
change_state(s, ipcp, AckReceived);
|
|
break;
|
|
|
|
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;
|
|
|
|
case AckSent:
|
|
ipcp_open(t, s);
|
|
break;
|
|
|
|
default:
|
|
LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
|
|
}
|
|
}
|
|
else if (*p == ConfigReq)
|
|
{
|
|
uint8_t *response = 0;
|
|
uint8_t *o = p + 4;
|
|
int length = l - 4;
|
|
int gotip = 0;
|
|
in_addr_t addr;
|
|
|
|
LOG(3, s, t, "IPCP: ConfigReq received\n");
|
|
|
|
while (length > 2)
|
|
{
|
|
switch (*o)
|
|
{
|
|
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)))
|
|
{
|
|
q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
|
|
if (!q || *response == ConfigRej)
|
|
{
|
|
sessionshutdown(s, "Can't negotiate IPCP.", 3, 0);
|
|
return;
|
|
}
|
|
}
|
|
|
|
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)))
|
|
{
|
|
q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
|
|
if (!q) return;
|
|
}
|
|
|
|
break;
|
|
|
|
case 131: // secondary DNS
|
|
if (o[1] != 6 || o[1] > length) 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));
|
|
if (!q) return;
|
|
}
|
|
|
|
break;
|
|
|
|
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);
|
|
if (!q) return;
|
|
}
|
|
|
|
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, t, s, 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, t, s, 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(t, s);
|
|
|
|
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: Sending %s\n", ppp_code(*response));
|
|
tunnelsend(b, l + (response - b), t);
|
|
}
|
|
else if (*p == TerminateReq)
|
|
{
|
|
LOG(3, s, t, "IPCP: Received TerminateReq. Sending TerminateAck\n");
|
|
*p = TerminateAck;
|
|
q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP);
|
|
if (!q) return;
|
|
tunnelsend(b, l + (q - b), t);
|
|
change_state(s, ipcp, Stopped);
|
|
}
|
|
else
|
|
{
|
|
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, t, s, PPPIPCP);
|
|
if (!q) return;
|
|
|
|
LOG(3, s, t, "Unexpected IPCP code %s\n", ppp_code(code));
|
|
tunnelsend(b, l + (q - b), t);
|
|
}
|
|
}
|
|
|
|
static void ipv6cp_open(tunnelidt t, sessionidt s)
|
|
{
|
|
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(t, s, NULL);
|
|
}
|
|
|
|
// Process IPV6CP messages
|
|
void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
|
|
{
|
|
uint8_t b[MAXCONTROL];
|
|
uint8_t *q = 0;
|
|
uint16_t hl;
|
|
|
|
CSTAT(processipv6cp);
|
|
|
|
LOG_HEX(5, "IPV6CP", p, l);
|
|
if (l < 4)
|
|
{
|
|
LOG(1, s, t, "Short IPV6CP %d bytes\n", l);
|
|
STAT(tunnel_rx_errors);
|
|
return ;
|
|
}
|
|
|
|
if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
|
|
{
|
|
LOG(1, s, t, "Length mismatch IPV6CP %u/%u\n", hl, l);
|
|
STAT(tunnel_rx_errors);
|
|
return ;
|
|
}
|
|
l = hl;
|
|
|
|
if (session[s].ppp.phase < Network)
|
|
{
|
|
LOG(2, s, t, "IPV6CP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
|
|
return;
|
|
}
|
|
|
|
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, t, s, 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));
|
|
return; // need IPCP to complete...
|
|
}
|
|
|
|
if (*p == ConfigAck)
|
|
{
|
|
switch (session[s].ppp.ipv6cp)
|
|
{
|
|
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(t, s);
|
|
break;
|
|
|
|
default:
|
|
LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
|
|
}
|
|
}
|
|
else if (*p == ConfigReq)
|
|
{
|
|
uint8_t *response = 0;
|
|
uint8_t *o = p + 4;
|
|
int length = l - 4;
|
|
int gotip = 0;
|
|
uint8_t ident[8];
|
|
|
|
LOG(3, s, t, "IPV6CP: ConfigReq received\n");
|
|
|
|
while (length > 2)
|
|
{
|
|
switch (*o)
|
|
{
|
|
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)))
|
|
{
|
|
q = ppp_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
|
|
if (!q) return;
|
|
}
|
|
|
|
break;
|
|
|
|
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);
|
|
if (!q) return;
|
|
}
|
|
|
|
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, t, s, PPPIPV6CP);
|
|
if (!response) return;
|
|
*response = ConfigAck;
|
|
}
|
|
else
|
|
{
|
|
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, t, s, 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(t, s);
|
|
|
|
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: Sending %s\n", ppp_code(*response));
|
|
tunnelsend(b, l + (response - b), t);
|
|
}
|
|
else if (*p == TerminateReq)
|
|
{
|
|
LOG(3, s, t, "IPV6CP: Received TerminateReq. Sending TerminateAck\n");
|
|
*p = TerminateAck;
|
|
q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP);
|
|
if (!q) return;
|
|
tunnelsend(b, l + (q - b), t);
|
|
change_state(s, ipv6cp, Stopped);
|
|
}
|
|
else
|
|
{
|
|
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, t, s, PPPIPV6CP);
|
|
if (!q) return;
|
|
|
|
LOG(3, s, t, "Unexpected IPV6CP code %s\n", ppp_code(code));
|
|
tunnelsend(b, l + (q - b), t);
|
|
}
|
|
}
|
|
|
|
// process IP packet received
|
|
//
|
|
// 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)
|
|
{
|
|
in_addr_t ip;
|
|
|
|
CSTAT(processipin);
|
|
|
|
LOG_HEX(5, "IP", p, l);
|
|
|
|
ip = ntohl(*(uint32_t *)(p + 12));
|
|
|
|
if (l > MAXETHER)
|
|
{
|
|
LOG(1, s, t, "IP packet too long %d\n", l);
|
|
STAT(tunnel_rx_errors);
|
|
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)
|
|
{
|
|
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;
|
|
*(uint32_t *) p = htonl(PKTIP);
|
|
l += 4;
|
|
|
|
// Are we throttled and a slave?
|
|
if (session[s].tbf_in && !config->cluster_iam_master) {
|
|
// Pass it to the master for handling.
|
|
master_throttle_packet(session[s].tbf_in, p, l);
|
|
return;
|
|
}
|
|
|
|
// Are we throttled and a master??
|
|
if (session[s].tbf_in && config->cluster_iam_master) {
|
|
// Actually handle the throttled packets.
|
|
tbf_queue_packet(session[s].tbf_in, p, l);
|
|
return;
|
|
}
|
|
|
|
// send to ethernet
|
|
if (tun_write(p, l) < 0)
|
|
{
|
|
STAT(tun_tx_errors);
|
|
LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
|
|
l, strerror(errno), tunfd, p);
|
|
|
|
return;
|
|
}
|
|
|
|
p += 4;
|
|
l -= 4;
|
|
|
|
if (session[s].snoop_ip && session[s].snoop_port)
|
|
{
|
|
// Snooping this session
|
|
snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
|
|
}
|
|
|
|
increment_counter(&session[s].cin, &session[s].cin_wrap, l);
|
|
session[s].cin_delta += l;
|
|
session[s].pin++;
|
|
|
|
sess_local[s].cin += l;
|
|
sess_local[s].pin++;
|
|
|
|
eth_tx += l;
|
|
|
|
STAT(tun_tx_packets);
|
|
INC_STAT(tun_tx_bytes, l);
|
|
}
|
|
|
|
// process IPv6 packet received
|
|
//
|
|
// 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)
|
|
{
|
|
struct in6_addr ip;
|
|
in_addr_t ipv4;
|
|
|
|
CSTAT(processipv6in);
|
|
|
|
LOG_HEX(5, "IPv6", p, l);
|
|
|
|
ip = *(struct in6_addr *) (p + 8);
|
|
ipv4 = ntohl(*(uint32_t *)(p + 16));
|
|
|
|
if (l > MAXETHER)
|
|
{
|
|
LOG(1, s, t, "IP packet too long %d\n", l);
|
|
STAT(tunnel_rx_errors);
|
|
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)
|
|
{
|
|
char str[INET6_ADDRSTRLEN];
|
|
LOG(5, s, t, "Dropping packet with spoofed IP %s\n",
|
|
inet_ntop(AF_INET6, &ip, str, INET6_ADDRSTRLEN));
|
|
return;
|
|
}
|
|
|
|
// Check if it's a Router Solicition message.
|
|
if (*(p + 6) == 58 && *(p + 7) == 255 && *(p + 24) == 0xFF && *(p + 25) == 2 &&
|
|
*(uint32_t *)(p + 26) == 0 && *(uint32_t *)(p + 30) == 0 &&
|
|
*(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);
|
|
return;
|
|
}
|
|
|
|
// Add on the tun header
|
|
p -= 4;
|
|
*(uint32_t *) p = htonl(PKTIPV6);
|
|
l += 4;
|
|
|
|
// Are we throttled and a slave?
|
|
if (session[s].tbf_in && !config->cluster_iam_master) {
|
|
// Pass it to the master for handling.
|
|
master_throttle_packet(session[s].tbf_in, p, l);
|
|
return;
|
|
}
|
|
|
|
// Are we throttled and a master??
|
|
if (session[s].tbf_in && config->cluster_iam_master) {
|
|
// Actually handle the throttled packets.
|
|
tbf_queue_packet(session[s].tbf_in, p, l);
|
|
return;
|
|
}
|
|
|
|
// send to ethernet
|
|
if (tun_write(p, l) < 0)
|
|
{
|
|
STAT(tun_tx_errors);
|
|
LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
|
|
l, strerror(errno), tunfd, p);
|
|
|
|
return;
|
|
}
|
|
|
|
p += 4;
|
|
l -= 4;
|
|
|
|
if (session[s].snoop_ip && session[s].snoop_port)
|
|
{
|
|
// Snooping this session
|
|
snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
|
|
}
|
|
|
|
increment_counter(&session[s].cin, &session[s].cin_wrap, l);
|
|
session[s].cin_delta += l;
|
|
session[s].pin++;
|
|
|
|
sess_local[s].cin += l;
|
|
sess_local[s].pin++;
|
|
|
|
eth_tx += l;
|
|
|
|
STAT(tun_tx_packets);
|
|
INC_STAT(tun_tx_bytes, l);
|
|
}
|
|
|
|
//
|
|
// Helper routine for the TBF filters.
|
|
// Used to send queued data in from the user.
|
|
//
|
|
void send_ipin(sessionidt s, uint8_t *buf, int len)
|
|
{
|
|
LOG_HEX(5, "IP in throttled", buf, len);
|
|
|
|
if (write(tunfd, buf, len) < 0)
|
|
{
|
|
STAT(tun_tx_errors);
|
|
LOG(0, 0, 0, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
|
|
len, strerror(errno), tunfd, buf);
|
|
|
|
return;
|
|
}
|
|
|
|
buf += 4;
|
|
len -= 4;
|
|
|
|
if (session[s].snoop_ip && session[s].snoop_port)
|
|
{
|
|
// Snooping this session
|
|
snoop_send_packet(buf, len, session[s].snoop_ip, session[s].snoop_port);
|
|
}
|
|
|
|
// Increment packet counters
|
|
increment_counter(&session[s].cin, &session[s].cin_wrap, len);
|
|
session[s].cin_delta += len;
|
|
session[s].pin++;
|
|
|
|
sess_local[s].cin += len;
|
|
sess_local[s].pin++;
|
|
|
|
eth_tx += len;
|
|
|
|
STAT(tun_tx_packets);
|
|
INC_STAT(tun_tx_bytes, len - 4);
|
|
}
|
|
|
|
|
|
// Process CCP messages
|
|
void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
|
|
{
|
|
uint8_t b[MAXCONTROL];
|
|
uint8_t *q;
|
|
|
|
CSTAT(processccp);
|
|
|
|
LOG_HEX(5, "CCP", p, l);
|
|
|
|
if (session[s].ppp.phase < Network)
|
|
{
|
|
LOG(2, s, t, "CCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
|
|
return;
|
|
}
|
|
|
|
if (l < 1)
|
|
{
|
|
LOG(1, s, t, "Short CCP packet\n");
|
|
STAT(tunnel_rx_errors);
|
|
}
|
|
|
|
if (*p == ConfigAck)
|
|
{
|
|
switch (session[s].ppp.ccp)
|
|
{
|
|
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;
|
|
|
|
q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP);
|
|
if (!q) return;
|
|
|
|
switch (session[s].ppp.ccp)
|
|
{
|
|
case Closed:
|
|
q = makeppp(b, sizeof(b), p, 2, t, s, PPPCCP);
|
|
if (!q) return;
|
|
*q = TerminateAck;
|
|
*((uint16_t *) (q + 2)) = htons(l = 4);
|
|
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);
|
|
|
|
break;
|
|
|
|
case RequestSent:
|
|
if (*q == ConfigAck)
|
|
change_state(s, ccp, AckSent);
|
|
|
|
break;
|
|
|
|
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;
|
|
|
|
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: Sending %s\n", ppp_code(*q));
|
|
tunnelsend(b, l + (q - b), t);
|
|
}
|
|
else if (*p == TerminateReq)
|
|
{
|
|
LOG(3, s, t, "CCP: Received TerminateReq. Sending TerminateAck\n");
|
|
*p = TerminateAck;
|
|
q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP);
|
|
if (!q) return;
|
|
tunnelsend(b, l + (q - b), t);
|
|
change_state(s, ccp, Stopped);
|
|
}
|
|
else
|
|
{
|
|
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, t, s, PPPCCP);
|
|
if (!q) return;
|
|
|
|
LOG(3, s, t, "Unexpected CCP code %s\n", ppp_code(code));
|
|
tunnelsend(b, l + (q - b), t);
|
|
}
|
|
}
|
|
|
|
// send a CHAP challenge
|
|
void sendchap(tunnelidt t, sessionidt s)
|
|
{
|
|
uint8_t b[MAXCONTROL];
|
|
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;
|
|
}
|
|
|
|
LOG(1, s, t, "Send CHAP challenge\n");
|
|
|
|
radius[r].chap = 1; // CHAP not PAP
|
|
radius[r].id++;
|
|
if (radius[r].state != RADIUSCHAP)
|
|
radius[r].try = 0;
|
|
|
|
radius[r].state = RADIUSCHAP;
|
|
radius[r].retry = backoff(radius[r].try++);
|
|
if (radius[r].try > 5)
|
|
{
|
|
sessionshutdown(s, "CHAP timeout.", 3, 0);
|
|
STAT(tunnel_tx_errors);
|
|
return ;
|
|
}
|
|
q = makeppp(b, sizeof(b), 0, 0, t, s, 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((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)
|
|
{
|
|
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 + 0) = htons(0x0002); // L2TP with no options
|
|
*(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))
|
|
{
|
|
*(uint16_t *) b = htons(0xFF03); // HDLC header
|
|
b += 2;
|
|
}
|
|
if (mtype < 0x100 && session[s].l2tp_flags & SESSIONPFC)
|
|
*b++ = mtype;
|
|
else
|
|
{
|
|
*(uint16_t *) b = htons(mtype);
|
|
b += 2;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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)
|
|
{
|
|
len = *b++ = 5; // length
|
|
*(uint16_t *) b = htons(PPPCHAP); b += 2;
|
|
*b++ = 5; // MD5
|
|
}
|
|
else if (authtype == AUTHPAP)
|
|
{
|
|
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 len;
|
|
}
|
|
|
|
// Send initial LCP ConfigReq for MRU, authentication type and magic no
|
|
void sendlcp(tunnelidt t, sessionidt s, int authtype)
|
|
{
|
|
uint8_t b[500], *q, *l;
|
|
|
|
if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP)))
|
|
return;
|
|
|
|
LOG(4, s, t, "Sending LCP ConfigReq%s%s\n",
|
|
authtype ? " for " : "",
|
|
authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : "");
|
|
|
|
if (!session[s].mru)
|
|
session[s].mru = DEFAULT_MRU;
|
|
|
|
l = q;
|
|
*l++ = ConfigReq;
|
|
*l++ = (time_now % 255) + 1; // 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 (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);
|
|
l += 4;
|
|
|
|
*(uint16_t *)(q + 2) = htons(l - q); // Length
|
|
|
|
LOG_HEX(5, "PPPLCP", q, l - q);
|
|
tunnelsend(b, (l - b), t);
|
|
}
|
|
|
|
// Send CCP request for no compression
|
|
void sendccp(tunnelidt t, sessionidt s)
|
|
{
|
|
uint8_t b[500], *q;
|
|
|
|
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;
|
|
*(uint8_t *)(q + 1) = (time_now % 255) + 1; // ID
|
|
*(uint16_t *)(q + 2) = htons(4); // Length
|
|
|
|
LOG_HEX(5, "PPPCCP", q, 4);
|
|
tunnelsend(b, (q - b) + 4 , t);
|
|
}
|