site.c: Make sure there's enough buffer space for the signature terminator.

[secnet] / site.c

diff --git a/site.c b/site.c
index 412567b..0da21ef 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
@@ -305,6 +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;
@@ -712,6 +713,13 @@ 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;
 }
 
@@ -845,7 +853,7 @@ 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!");
@@ -1187,7 +1195,16 @@ static bool_t comm_addr_sendmsg(struct site *st,
                                const struct comm_addr *dest,
                                struct buffer_if *buf)
 {
-    return dest->comm->sendmsg(dest->comm->st, buf, dest);
+    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)
@@ -2033,6 +2050,14 @@ 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);