chiark / gitweb /
site: Log about crossed MSG1 ignored only once
[secnet.git] / site.c
diff --git a/site.c b/site.c
index bffd327dea53a45af6edbab8361a9c81c875d478..11fc28be2443973ab84c30490a7d79dd09efabf0 100644 (file)
--- a/site.c
+++ b/site.c
@@ -6,7 +6,7 @@
  *
  * secnet is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version d of the License, or
+ * the Free Software Foundation; either version 3 of the License, or
  * (at your option) any later version.
  * 
  * secnet is distributed in the hope that it will be useful, but
@@ -296,6 +296,7 @@ struct site {
 /* configuration information */
     string_t localname;
     string_t remotename;
+    bool_t keepalive;
     bool_t local_mobile, peer_mobile; /* Mobile client support */
     int32_t transport_peers_max;
     string_t tunname; /* localname<->remotename by default, used in logs */
@@ -304,6 +305,7 @@ struct site {
     uint32_t mtu_target;
     struct netlink_if *netlink;
     struct comm_if **comms;
+    struct comm_clientinfo **commclientinfos;
     int ncomms;
     struct resolver_if *resolver;
     struct log_if *log;
@@ -334,6 +336,7 @@ struct site {
     uint32_t state;
     uint64_t now; /* Most recently seen time */
     bool_t allow_send_prod;
+    bool_t msg1_crossed_logged;
     int resolving_count;
     int resolving_n_results_all;
     int resolving_n_results_stored;
@@ -532,8 +535,10 @@ struct msg {
     char *sig;
 };
 
-static void set_new_transform(struct site *st, char *pk)
+static _Bool set_new_transform(struct site *st, char *pk)
 {
+    _Bool ok;
+
     /* Make room for the shared key */
     st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
     assert(st->sharedsecretlen);
@@ -551,15 +556,18 @@ static void set_new_transform(struct site *st, char *pk)
     /* Set up the transform */
     struct transform_if *generator=st->chosen_transform;
     struct transform_inst_if *generated=generator->create(generator->st);
-    generated->setkey(generated->st,st->sharedsecret,
-                     st->sharedsecretlen,st->setup_priority);
+    ok = generated->setkey(generated->st,st->sharedsecret,
+                          st->sharedsecretlen,st->setup_priority);
+
     dispose_transform(&st->new_transform);
+    if (!ok) return False;
     st->new_transform=generated;
 
     slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
         " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
         st->chosen_transform->capab_transformnum,
         st->local_capabilities, st->remote_capabilities);
+    return True;
 }
 
 struct xinfoadd {
@@ -711,6 +719,13 @@ static bool_t unpick_msg(struct site *st, uint32_t type,
     CHECK_AVAIL(msg,m->siglen);
     m->sig=buf_unprepend(msg,m->siglen);
     CHECK_EMPTY(msg);
+
+    /* In `process_msg3_msg4' below, we assume that we can write a nul
+     * terminator following the signature.  Make sure there's enough space.
+     */
+    if (msg->start >= msg->base + msg->alloclen)
+       return False;
+
     return True;
 }
 
@@ -844,7 +859,7 @@ static bool_t process_msg3_msg4(struct site *st, struct msg *m)
     hst=st->hash->init();
     st->hash->update(hst,m->hashstart,m->hashlen);
     st->hash->final(hst,hash);
-    /* Terminate signature with a '0' - cheating, but should be ok */
+    /* Terminate signature with a '0' - already checked that this will fit */
     m->sig[m->siglen]=0;
     if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
        slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
@@ -903,7 +918,7 @@ static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
     st->random->generate(st->random->st,st->dh->len,st->dhsecret);
 
     /* Generate the shared key and set up the transform */
-    set_new_transform(st,m.pk);
+    if (!set_new_transform(st,m.pk)) return False;
 
     return True;
 }
@@ -934,7 +949,7 @@ static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
     m.pk[m.pklen]=0;
 
     /* Generate the shared key and set up the transform */
-    set_new_transform(st,m.pk);
+    if (!set_new_transform(st,m.pk)) return False;
 
     return True;
 }
@@ -1129,7 +1144,8 @@ static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
 
  skew:
     slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
-    return False;
+    assert(problem);
+    return problem;
 }
 
 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
@@ -1146,6 +1162,10 @@ static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
     case LABEL_MSG7:
        /* We must forget about the current session. */
        delete_keys(st,"request from peer",LOG_SEC);
+       /* probably, the peer is shutting down, and this is going to fail,
+        * but we need to be trying to bring the link up again */
+       if (st->keepalive)
+           initiate_key_setup(st,"peer requested key teardown",0);
        return True;
     case LABEL_MSG9:
        /* Deliver to netlink layer */
@@ -1178,6 +1198,22 @@ static void dump_packet(struct site *st, struct buffer_if *buf,
               ok?"":" - fail");
 }
 
+static bool_t comm_addr_sendmsg(struct site *st,
+                               const struct comm_addr *dest,
+                               struct buffer_if *buf)
+{
+    int i;
+    struct comm_clientinfo *commclientinfo = 0;
+
+    for (i=0; i < st->ncomms; i++) {
+       if (st->comms[i] == dest->comm) {
+           commclientinfo = st->commclientinfos[i];
+           break;
+       }
+    }
+    return dest->comm->sendmsg(dest->comm->st, buf, dest, commclientinfo);
+}
+
 static uint32_t site_status(void *st)
 {
     return 0;
@@ -1427,8 +1463,11 @@ static void enter_state_run(struct site *st)
     FILLZERO(st->remoteN);
     dispose_transform(&st->new_transform);
     memset(st->dhsecret,0,st->dh->len);
-    memset(st->sharedsecret,0,st->sharedsecretlen);
+    if (st->sharedsecret) memset(st->sharedsecret,0,st->sharedsecretlen);
     set_link_quality(st);
+
+    if (st->keepalive && !current_valid(st))
+       initiate_key_setup(st, "keepalive", 0);
 }
 
 static bool_t ensure_resolving(struct site *st)
@@ -1487,6 +1526,7 @@ static bool_t enter_new_state(struct site *st, uint32_t next)
     case SITE_SENTMSG1:
        state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
        gen=generate_msg1;
+       st->msg1_crossed_logged = False;
        break;
     case SITE_SENTMSG2:
        state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
@@ -1602,7 +1642,7 @@ static void generate_send_prod(struct site *st,
     slog(st,LOG_SETUP_INIT,"prodding peer for key exchange");
     st->allow_send_prod=0;
     generate_prod(st,&st->scratch);
-    bool_t ok = source->comm->sendmsg(source->comm->st, &st->scratch, source);
+    bool_t ok = comm_addr_sendmsg(st, source, &st->scratch);
     dump_packet(st,&st->scratch,source,False,ok);
 }
 
@@ -1759,8 +1799,9 @@ static bool_t site_incoming(void *sst, struct buffer_if *buf,
               incoming one, otherwise we process it as usual. */
            if (st->setup_priority) {
                BUF_FREE(buf);
-               slog(st,LOG_DUMP,"crossed msg1s; we are higher "
-                    "priority => ignore incoming msg1");
+               if (!st->msg1_crossed_logged++)
+                   slog(st,LOG_DUMP,"crossed msg1s; we are higher "
+                        "priority => ignore incoming msg1");
                return True;
            } else {
                slog(st,LOG_DUMP,"crossed msg1s; we are lower "
@@ -1967,6 +2008,8 @@ static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
     st->localname=dict_read_string(dict, "local-name", True, "site", loc);
     st->remotename=dict_read_string(dict, "name", True, "site", loc);
 
+    st->keepalive=dict_read_bool(dict,"keepalive",False,"site",loc,False);
+
     st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
     st->local_mobile=
        dict_read_bool(dict,"local-mobile",False,"site",loc,False);
@@ -2016,6 +2059,14 @@ static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
 
     GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
 
+    NEW_ARY(st->commclientinfos, st->ncomms);
+    dict_t *comminfo = dict_read_dict(dict,"comm-info",False,"site",loc);
+    for (i=0; i<st->ncomms; i++) {
+       st->commclientinfos[i] =
+           !comminfo ? 0 :
+           st->comms[i]->clientinfo(st->comms[i],comminfo,loc);
+    }
+
     st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
     st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
     st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
@@ -2214,11 +2265,18 @@ static void transport_record_peers(struct site *st, transport_peers *peers,
      *
      * Caller must first call transport_peers_expire. */
 
-    if (naddrs==1 && peers->npeers>=1 &&
-       comm_addr_equal(&addrs[0], &peers->peers[0].addr)) {
-       /* optimisation, also avoids debug for trivial updates */
-       peers->peers[0].last = *tv_now;
-       return;
+    if (naddrs==1) {
+       /* avoids debug for uninteresting updates */
+       int i;
+       for (i=0; i<peers->npeers; i++) {
+           if (comm_addr_equal(&addrs[0], &peers->peers[i].addr)) {
+               memmove(peers->peers+1, peers->peers,
+                       sizeof(peers->peers[0]) * i);
+               peers->peers[0].addr = addrs[0];
+               peers->peers[0].last = *tv_now;
+               return;
+           }
+       }
     }
 
     int old_npeers=peers->npeers;
@@ -2349,8 +2407,7 @@ void transport_xmit(struct site *st, transport_peers *peers,
     int nfailed=0;
     for (slot=0; slot<peers->npeers; slot++) {
        transport_peer *peer=&peers->peers[slot];
-       bool_t ok =
-           peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
+       bool_t ok = comm_addr_sendmsg(st, &peer->addr, buf);
        if (candebug)
            dump_packet(st, buf, &peer->addr, False, ok);
        if (!ok) {
@@ -2374,12 +2431,14 @@ void transport_xmit(struct site *st, transport_peers *peers,
            transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
            assert(wslot+nfailed == peers->npeers);
            COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
+           transport_peers_debug(st,peers,"mobile failure reorder",0,0,0);
        }
     } else {
        if (failed && peers->npeers > 1) {
            int wslot=0;
            transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
            peers->npeers=wslot;
+           transport_peers_debug(st,peers,"non-mobile failure cleanup",0,0,0);
        }
     }
 }