noip.c (do_implicit_bind): Handle `SAME' impbind entries properly.

[preload-hacks] / noip.c

diff --git a/noip.c b/noip.c
index fea6f742adaac68c2299016c9857b3b31e1c0630..345f3251d7c56d2e591fedee22b663e8b330e505 100644 (file)
--- a/noip.c
+++ b/noip.c
@@ -57,12 +57,18 @@
 #include <ifaddrs.h>
 #include <netdb.h>
 
+#ifndef SUN_LEN
+#  define SUN_LEN (sun) \
+       (strlen((sun)->sun_path) + offsetof(struct sockaddr_un, sun_path))
+#endif
+
 /*----- Data structures ---------------------------------------------------*/
 
 /* Unix socket status values. */
 #define UNUSED 0u                      /* No sign of anyone using it */
 #define STALE 1u                       /* Socket exists, but is abandoned */
 #define USED 16u                       /* Socket is in active use */
+#define LISTEN 2u                      /* Socket has an active listener */
 
 enum { DENY, ALLOW };                  /* ACL verdicts */
 
@@ -680,6 +686,7 @@ static int unix_socket_status(struct sockaddr_un *sun, int quickp)
   FILE *fp = 0;
   size_t len, n;
   int rc;
+  unsigned long f;
   char buf[256];
 
   /* If we can't find the socket node, then it's definitely not in use.  If
@@ -710,6 +717,8 @@ static int unix_socket_status(struct sockaddr_un *sun, int quickp)
     if (n >= len + 2 && buf[n - len - 2] == ' ' && buf[n - 1] == '\n' &&
        memcmp(buf + n - len - 1, sun->sun_path, len) == 0) {
       rc |= USED;
+      if (sscanf(buf, "%*s %*x %*x %lx", &f) < 0 || (f&0x00010000))
+       rc |= LISTEN;
     }
   }
   if (ferror(fp))
@@ -796,6 +805,7 @@ static int encode_unused_inet_addr(struct sockaddr *sa,
  * Returns zero on success; -1 on failure.
  */
 #define ENCF_FRESH 1u
+#define ENCF_REUSEADDR 2u
 static int encode_inet_addr(struct sockaddr_un *sun,
                            const struct sockaddr *sa,
                            unsigned f)
@@ -821,6 +831,7 @@ static int encode_inet_addr(struct sockaddr_un *sun,
      * want an existing socket, then we're done.
      */
     rc = encode_single_inet_addr(sa, sun, 0);
+    if ((f&ENCF_REUSEADDR) && !(rc&LISTEN)) unlink(sun->sun_path);
     if ((rc&USED) || (f&ENCF_FRESH)) goto found;
 
     /* We're looking for a socket which already exists.  This is
@@ -1116,7 +1127,11 @@ static int do_implicit_bind(int sk, const struct sockaddr *sa, unsigned f)
        sockaddr_in_range_p(sa, &i->minaddr, &i->maxaddr)) {
       D( fprintf(stderr, "noip(%d): match!\n", pid); )
       addr.sa.sa_family = sa->sa_family;
-      ipaddr_to_sockaddr(&addr.sa, &i->bindaddr);
+      switch (i->how) {
+       case EXPLICIT: ipaddr_to_sockaddr(&addr.sa, &i->bindaddr); break;
+       case SAME: copy_sockaddr(&addr.sa, sa); break;
+      }
+      port_to_sockaddr(&addr.sa, 0);
       goto found;
     }
   }
@@ -1719,6 +1734,9 @@ int bind(int sk, const struct sockaddr *sa, socklen_t len)
 {
   struct sockaddr_un sun;
   int rc;
+  unsigned f;
+  int reusep;
+  socklen_t n;
   Dpid;
 
   D({ char buf[ADDRBUFSZ];
@@ -1734,7 +1752,11 @@ int bind(int sk, const struct sockaddr *sa, socklen_t len)
        if (fixup_real_ip_socket(sk, sa->sa_family, 0))
          return (-1);
       } else {
-       encode_inet_addr(&sun, sa, ENCF_FRESH);
+       f = ENCF_FRESH;
+       n = sizeof(reusep);
+       if (!getsockopt(sk, SOL_SOCKET, SO_REUSEADDR, &reusep, &n) && reusep)
+         f |= ENCF_REUSEADDR;
+       encode_inet_addr(&sun, sa, f);
        sa = SA(&sun);
        len = SUN_LEN(&sun);
       }
@@ -1952,7 +1974,7 @@ int getpeername(int sk, struct sockaddr *sa, socklen_t *len)
     D( fprintf(stderr, "noip(%d): ... GETPEERNAME", pid); )
   }
   D( dump_addrresult(rc, sa, *len); )
-  return (0);
+  return (rc);
 }
 
 int getsockopt(int sk, int lev, int opt, void *p, socklen_t *len)