Ping new master when we get C_MASTER and delay next election to allow

[l2tpns.git] / l2tpns.c

diff --git a/l2tpns.c b/l2tpns.c
index 733ca6d..7ce6e6b 100644 (file)
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -4,7 +4,7 @@
 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
 // vim: sw=8 ts=8
 
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.108 2005/06/04 15:42:35 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.111 2005/06/14 04:47:24 bodea Exp $";
 
 #include <arpa/inet.h>
 #include <assert.h>
@@ -177,8 +177,7 @@ static void free_ip_address(sessionidt s);
 static void dump_acct_info(int all);
 static void sighup_handler(int sig);
 static void sigalrm_handler(int sig);
-static void sigterm_handler(int sig);
-static void sigquit_handler(int sig);
+static void shutdown_handler(int sig);
 static void sigchild_handler(int sig);
 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
 static void update_config(void);
@@ -194,6 +193,10 @@ static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vec
 // on slaves, alow BGP to withdraw cleanly before exiting
 #define QUIT_DELAY     5
 
+// quit actions (master)
+#define QUIT_FAILOVER  1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
+#define QUIT_SHUTDOWN  2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
+
 // return internal time (10ths since process startup), set f if given
 static clockt now(double *f)
 {
@@ -323,7 +326,8 @@ static void initrandom(char *source)
                return;
 
        // close previous source, if any
-       if (rand_fd >= 0) close(rand_fd);
+       if (rand_fd >= 0)
+               close(rand_fd);
 
        rand_fd = -1;
 
@@ -340,13 +344,6 @@ static void initrandom(char *source)
                                        path, strerror(errno));
                }
        }
-
-       // no source: seed prng
-       {
-               unsigned seed = time_now ^ getpid();
-               LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
-               srand(seed);
-       }
 }
 
 // fill buffer with random data
@@ -367,7 +364,7 @@ void random_data(uint8_t *buf, int len)
                                        strerror(errno));
 
                                // fall back to rand()
-                               initrandom(0);
+                               initrandom(NULL);
                        }
 
                        n = 0;
@@ -1717,7 +1714,7 @@ static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, cha
        // close session
        for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
                if (session[s].tunnel == t)
-                       sessionshutdown(s, reason, 3, 0);
+                       sessionshutdown(s, reason, 0, 0);
 
        tunnel[t].state = TUNNELDIE;
        tunnel[t].die = TIME + 700; // Clean up in 70 seconds
@@ -2027,8 +2024,6 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                continue;
                                        }
 
-                                       LOG(4, s, t, "Hidden AVP\n");
-
                                        // Unhide the AVP
                                        unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
 
@@ -2049,7 +2044,9 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        n = orig_len;
                                }
 
-                               LOG(4, s, t, "   AVP %d (%s) len %d\n", mtype, avp_name(mtype), n);
+                               LOG(4, s, t, "   AVP %d (%s) len %d%s%s\n", mtype, avp_name(mtype), n,
+                                       flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
+
                                switch (mtype)
                                {
                                case 0:     // message type
@@ -2271,6 +2268,8 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                case 36:    // Random Vector
                                        LOG(4, s, t, "   Random Vector received.  Enabled AVP Hiding.\n");
                                        memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
+                                       if (n > sizeof(session[s].random_vector))
+                                               n = sizeof(session[s].random_vector);
                                        memcpy(session[s].random_vector, b, n);
                                        session[s].random_vector_length = n;
                                        break;
@@ -2293,6 +2292,8 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                switch (message)
                                {
                                case 1:       // SCCRQ - Start Control Connection Request
+                                       tunnel[t].state = TUNNELOPENING;
+                                       if (main_quit != QUIT_SHUTDOWN)
                                        {
                                                controlt *c = controlnew(2); // sending SCCRP
                                                control16(c, 2, version, 1); // protocol version
@@ -2302,7 +2303,10 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                                control16(c, 9, t, 1); // assigned tunnel
                                                controladd(c, t, 0); // send the resply
                                        }
-                                       tunnel[t].state = TUNNELOPENING;
+                                       else
+                                       {
+                                               tunnelshutdown(t, "Shutting down", 6, 0, 0);
+                                       }
                                        break;
                                case 2:       // SCCRP
                                        tunnel[t].state = TUNNELOPEN;
@@ -2328,7 +2332,7 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
                                        // TBA
                                        break;
                                case 10:      // ICRQ
-                                       if (sessionfree)
+                                       if (sessionfree && main_quit != QUIT_SHUTDOWN)
                                        {
                                                uint16_t r;
 
@@ -2370,8 +2374,12 @@ void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
 
                                        {
                                                controlt *c = controlnew(14); // CDN
-                                               control16(c, 1, 4, 1); // temporary lack of resources
-                                               controladd(c, session[s].tunnel, asession); // send the message
+                                               if (main_quit == QUIT_SHUTDOWN)
+                                                       control16(c, 1, 2, 7); // try another
+                                               else
+                                                       control16(c, 1, 4, 0); // temporary lack of resources
+
+                                               controladd(c, t, asession); // send the message
                                        }
                                        return;
                                case 11:      // ICRP
@@ -2885,6 +2893,22 @@ static int still_busy(void)
                return 0;
        }
 
+       if (main_quit == QUIT_SHUTDOWN)
+       {
+               static int dropped = 0;
+               if (!dropped)
+               {
+                       int i;
+
+                       LOG(1, 0, 0, "Dropping sessions and tunnels\n");
+                       for (i = 1; i < MAXTUNNEL; i++)
+                               if (tunnel[i].ip || tunnel[i].state)
+                                       tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
+
+                       dropped = 1;
+               }
+       }
+
        if (start_busy_wait == 0)
                start_busy_wait = TIME;
 
@@ -3031,8 +3055,7 @@ static void mainloop(void)
                                continue;
 
                        LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
-                       main_quit++;
-                       break;
+                       break; // exit
                }
 
                if (n)
@@ -3253,7 +3276,7 @@ static void mainloop(void)
 
        //
        // Important!!! We MUST not process any packets past this point!
-       LOG(1, 0, 0, "Clean shutdown complete\n");
+       LOG(1, 0, 0, "Shutdown complete\n");
 }
 
 static void stripdomain(char *host)
@@ -3902,11 +3925,18 @@ int main(int argc, char *argv[])
        initrad();
        initippool();
 
-       signal(SIGHUP, sighup_handler);
-       signal(SIGTERM, sigterm_handler);
-       signal(SIGINT, sigterm_handler);
-       signal(SIGQUIT, sigquit_handler);
+       // seed prng
+       {
+               unsigned seed = time_now ^ getpid();
+               LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
+               srand(seed);
+       }
+
+       signal(SIGHUP,  sighup_handler);
        signal(SIGCHLD, sigchild_handler);
+       signal(SIGTERM, shutdown_handler);
+       signal(SIGINT,  shutdown_handler);
+       signal(SIGQUIT, shutdown_handler);
 
        // Prevent us from getting paged out
        if (config->lock_pages)
@@ -3984,33 +4014,10 @@ static void sigalrm_handler(int sig)
 
 }
 
-static void sigterm_handler(int sig)
-{
-       LOG(1, 0, 0, "Shutting down cleanly\n");
-       main_quit++;
-}
-
-static void sigquit_handler(int sig)
+static void shutdown_handler(int sig)
 {
-       int i;
-
-       LOG(1, 0, 0, "Shutting down without saving sessions\n");
-
-       if (config->cluster_iam_master)
-       {
-               for (i = 1; i < MAXSESSION; i++)
-               {
-                       if (session[i].opened)
-                               sessionkill(i, "L2TPNS Closing");
-               }
-               for (i = 1; i < MAXTUNNEL; i++)
-               {
-                       if (tunnel[i].ip || tunnel[i].state)
-                               tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
-               }
-       }
-
-       main_quit++;
+       LOG(1, 0, 0, "Shutting down\n");
+       main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
 }
 
 static void sigchild_handler(int sig)
@@ -4285,7 +4292,7 @@ int sessionsetup(tunnelidt t, sessionidt s)
                if (!session[s].ip)
                {
                        LOG(0, s, t, "   No IP allocated.  The IP address pool is FULL!\n");
-                       sessionshutdown(s, "No IP addresses available.", 2, 7);
+                       sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
                        return 0;
                }
                LOG(3, s, t, "   No IP allocated.  Assigned %s from pool\n",
@@ -5004,11 +5011,11 @@ static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vec
        uint8_t digest[16];
        uint8_t *last;
        size_t d = 0;
+       uint16_t m = htons(type);
 
        // Compute initial pad
        MD5Init(&ctx);
-       MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
-       MD5Update(&ctx, (uint8_t)  type       & 0xff, 1);
+       MD5Update(&ctx, (unsigned char *) &m, 2);
        MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
        MD5Update(&ctx, vector, vec_len);
        MD5Final(digest, &ctx);