When printing messages about dropping IPv6, do not print anything about ihl.

[secnet.git] / secnet.c

diff --git a/secnet.c b/secnet.c
index 4520b3e5ed91644939a7f9824a8c9a377e564a9a..8fb8affe43f80d6cebab337e504524b7f3907756 100644 (file)
--- a/secnet.c
+++ b/secnet.c
@@ -1,3 +1,22 @@
+/*
+ * This file is part of secnet.
+ * See README for full list of copyright holders.
+ *
+ * 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
+ * (at your option) any later version.
+ * 
+ * secnet is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * version 3 along with secnet; if not, see
+ * https://www.gnu.org/licenses/gpl.html.
+ */
+
 #include "secnet.h"
 #include <stdio.h>
 #include <assert.h>
@@ -36,7 +55,7 @@ static pid_t secnet_pid;
 
 /* Structures dealing with poll() call */
 struct poll_interest {
-    beforepoll_fn *before;
+    beforepoll_fn *before; /* 0 if deregistered and waiting to be deleted */
     afterpoll_fn *after;
     void *state;
     int32_t nfds;
@@ -45,6 +64,11 @@ struct poll_interest {
 };
 static LIST_HEAD(, poll_interest) reg = LIST_HEAD_INITIALIZER(&reg);
 
+static bool_t interest_isregistered(const struct poll_interest *i)
+{
+    return !!i->before;
+}
+
 static bool_t finished=False;
 
 /* Parse the command line options */
@@ -225,19 +249,27 @@ static void setup(dict_t *config)
     }
 }
 
-void register_for_poll(void *st, beforepoll_fn *before,
+struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
                       afterpoll_fn *after, cstring_t desc)
 {
     struct poll_interest *i;
 
-    i=safe_malloc(sizeof(*i),"register_for_poll");
+    NEW(i);
     i->before=before;
     i->after=after;
     i->state=st;
     i->nfds=0;
     i->desc=desc;
     LIST_INSERT_HEAD(&reg, i, entry);
-    return;
+    return i;
+}
+
+void deregister_for_poll(struct poll_interest *i)
+{
+    /* We cannot simply throw this away because we're reentrantly
+     * inside the main loop, which needs to remember which range of
+     * fds corresponds to this now-obsolete interest */
+    i->before=0;
 }
 
 static void system_phase_hook(void *sst, uint32_t newphase)
@@ -288,7 +320,7 @@ uint64_t now_global;
 
 static void run(void)
 {
-    struct poll_interest *i;
+    struct poll_interest *i, *itmp;
     int rv, nfds, idx;
     int timeout;
     struct pollfd *fds=0;
@@ -305,38 +337,51 @@ static void run(void)
        idx=0;
        LIST_FOREACH(i, &reg, entry) {
            int check;
-           for (check=0; check<i->nfds; check++) {
-               if(fds[idx+check].revents & POLLNVAL) {
-                   fatal("run: poll (%s#%d) set POLLNVAL", i->desc, check);
+           if (interest_isregistered(i)) {
+               for (check=0; check<i->nfds; check++) {
+                   if(fds[idx+check].revents & POLLNVAL) {
+                       fatal("run: poll (%s#%d) set POLLNVAL", i->desc, check);
+                   }
                }
+               i->after(i->state, fds+idx, i->nfds);
            }
-           i->after(i->state, fds+idx, i->nfds);
            idx+=i->nfds;
        }
        if (shortfall) {
            allocdfds *= 2;
            allocdfds += shortfall;
-           fds=safe_realloc_ary(fds,sizeof(*fds),allocdfds, "run");
+           REALLOC_ARY(fds,allocdfds);
        }
        shortfall=0;
        idx=0;
        timeout=-1;
-       LIST_FOREACH(i, &reg, entry) {
+       LIST_FOREACH_SAFE(i, &reg, entry, itmp) {
            int remain=allocdfds-idx;
            nfds=remain;
-           rv=i->before(i->state, fds+idx, &nfds, &timeout);
-           if (rv!=0) {
-               if (rv!=ERANGE)
-                   fatal("run: beforepoll_fn (%s) returns %d",i->desc,rv);
-               assert(nfds < INT_MAX/4 - shortfall);
-               shortfall += nfds-remain;
+           if (interest_isregistered(i)) {
+               rv=i->before(i->state, fds+idx, &nfds, &timeout);
+               if (rv!=0) {
+                   if (rv!=ERANGE)
+                       fatal("run: beforepoll_fn (%s) returns %d",i->desc,rv);
+                   assert(nfds < INT_MAX/4 - shortfall);
+                   shortfall += nfds-remain;
+                   nfds=0;
+                   timeout=0;
+               }
+           } else {
                nfds=0;
-               timeout=0;
            }
            if (timeout<-1) {
                fatal("run: beforepoll_fn (%s) set timeout to %d",
                      i->desc,timeout);
            }
+           if (!interest_isregistered(i)) {
+               /* check this here, rather than earlier, so that we
+                  handle the case where i->before() calls deregister */
+               LIST_REMOVE(i, entry);
+               free(i);
+               continue;
+           }
            idx+=nfds;
            i->nfds=nfds;
        }
@@ -357,6 +402,12 @@ static void run(void)
     free(fds);
 }
 
+bool_t will_droppriv(void)
+{
+    assert(current_phase >= PHASE_SETUP);
+    return !!uid;
+}
+
 /* Surrender privileges, if necessary */
 static void droppriv(void)
 {
@@ -443,6 +494,8 @@ int main(int argc, char **argv)
 {
     dict_t *config;
 
+    phase_hooks_init();
+
     enter_phase(PHASE_GETOPTS);
     parse_options(argc,argv);