X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=src%2Fguestfs.c;h=e0f60f4d42f5732541711c95b7676564e312343e;hb=26991ebb8181b57f4c8454f2862c938d7c5d012d;hp=850264e1c03924f0c7cc54ff22fcb093c1031396;hpb=d4a202aa7bf45382e84f558239dadc24c73d195d;p=libguestfs.git

diff --git a/src/guestfs.c b/src/guestfs.c
index 850264e..e0f60f4 100644
--- a/src/guestfs.c
+++ b/src/guestfs.c
@@ -86,6 +86,12 @@
 #define safe_strdup guestfs_safe_strdup
 //#define safe_memdup guestfs_safe_memdup
 
+#ifdef __linux__
+#define CAN_CHECK_PEER_EUID 1
+#else
+#define CAN_CHECK_PEER_EUID 0
+#endif
+
 static void default_error_cb (guestfs_h *g, void *data, const char *msg);
 static int send_to_daemon (guestfs_h *g, const void *v_buf, size_t n);
 static int recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn);
@@ -104,8 +110,27 @@ static int qemu_supports (guestfs_h *g, const char *option);
 #define xdr_uint32_t xdr_u_int32_t
 #endif
 
-/* Also in guestfsd.c */
-#define GUESTFWD_ADDR "10.0.2.4"
+/* Network configuration of the appliance.  Note these addresses are
+ * only meaningful within the context of the running appliance.  QEMU
+ * translates network connections to these magic addresses into
+ * userspace calls on the host (eg. connect(2)).  qemu-doc has a nice
+ * diagram which is also useful to refer to.
+ *
+ * NETWORK: The network.
+ *
+ * ROUTER: The address of the "host", ie. this library.
+ *
+ * [Note: If you change NETWORK and ROUTER then you also have to
+ * change the network configuration in appliance/init].
+ *
+ * GUESTFWD_ADDR, GUESTFWD_PORT: The guestfwd feature of qemu
+ * magically connects this pseudo-address to the guestfwd channel.  In
+ * typical Linux configurations of libguestfs, guestfwd is not
+ * actually used any more.
+ */
+#define NETWORK "169.254.0.0/16"
+#define ROUTER "169.254.2.2"
+#define GUESTFWD_ADDR "169.254.2.4"
 #define GUESTFWD_PORT "6666"
 
 /* GuestFS handle and connection. */
@@ -1053,7 +1078,7 @@ guestfs__launch (guestfs_h *g)
     goto cleanup0;
 
   /* Choose which vmchannel implementation to use. */
-  if (qemu_supports (g, "-net user")) {
+  if (CAN_CHECK_PEER_EUID && qemu_supports (g, "-net user")) {
     /* The "null vmchannel" implementation.  Requires SLIRP (user mode
      * networking in qemu) but no other vmchannel support.  The daemon
      * will connect back to a random port number on localhost.
@@ -1183,10 +1208,11 @@ guestfs__launch (guestfs_h *g)
      */
     if (null_vmchannel_sock) {
       add_cmdline (g, "-net");
-      add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
+      add_cmdline (g, "user,vlan=0,net=" NETWORK);
 
       snprintf (buf, sizeof buf,
-                "guestfs_vmchannel=tcp:10.0.2.2:%d", null_vmchannel_sock);
+                "guestfs_vmchannel=tcp:" ROUTER ":%d",
+                null_vmchannel_sock);
       vmchannel = strdup (buf);
     }
 
@@ -1209,7 +1235,7 @@ guestfs__launch (guestfs_h *g)
       add_cmdline (g, buf);
 
       snprintf (buf, sizeof buf,
-                "user,vlan=0,net=10.0.2.0/8,"
+                "user,vlan=0,net=" NETWORK ","
                 "guestfwd=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT
                 "-chardev:guestfsvmc");
 
@@ -1229,7 +1255,7 @@ guestfs__launch (guestfs_h *g)
       add_cmdline (g, "-net");
       add_cmdline (g, buf);
       add_cmdline (g, "-net");
-      add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
+      add_cmdline (g, "user,vlan=0,net=" NETWORK);
 
       vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT;
     }
@@ -1251,10 +1277,12 @@ guestfs__launch (guestfs_h *g)
               "%s "             /* (selinux) */
               "%s "             /* (vmchannel) */
               "%s "             /* (verbose) */
+              "TERM=%s "        /* (TERM environment variable) */
               "%s",             /* (append) */
               g->selinux ? "selinux=1 enforcing=0" : "selinux=0",
               vmchannel ? vmchannel : "",
               g->verbose ? "guestfs_verbose=1" : "",
+              getenv ("TERM") ? : "linux",
               g->append ? g->append : "");
 
     add_cmdline (g, "-kernel");
@@ -1281,7 +1309,7 @@ guestfs__launch (guestfs_h *g)
       if (dup (wfd[0]) == -1) {
       dup_failed:
         perror ("dup failed");
-        _exit (1);
+        _exit (EXIT_FAILURE);
       }
       if (dup (rfd[1]) == -1)
         goto dup_failed;
@@ -1301,7 +1329,7 @@ guestfs__launch (guestfs_h *g)
 
     execv (g->qemu, g->cmdline); /* Run qemu. */
     perror (g->qemu);
-    _exit (1);
+    _exit (EXIT_FAILURE);
   }
 
   /* Parent (library). */
@@ -1333,11 +1361,11 @@ guestfs__launch (guestfs_h *g)
        */
       for (;;) {
         if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */
-          _exit (0);
+          _exit (EXIT_SUCCESS);
         if (kill (parent_pid, 0) == -1) {
           /* Parent's gone away, qemu still around, so kill qemu. */
           kill (qemu_pid, 9);
-          _exit (0);
+          _exit (EXIT_SUCCESS);
         }
         sleep (2);
       }
@@ -1397,6 +1425,7 @@ guestfs__launch (guestfs_h *g)
                  "libguestfs: warning: unexpected connection from UID %d to port %d\n",
                  uid, null_vmchannel_sock);
         close (sock);
+        sock = -1;
         continue;
       }
     }
@@ -1491,7 +1520,7 @@ guestfs__launch (guestfs_h *g)
     close (wfd[1]);
     close (rfd[0]);
   }
-  kill (g->pid, 9);
+  if (g->pid > 0) kill (g->pid, 9);
   if (g->recoverypid > 0) kill (g->recoverypid, 9);
   waitpid (g->pid, NULL, 0);
   if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
@@ -1737,6 +1766,7 @@ is_openable (guestfs_h *g, const char *path, int flags)
 static int
 check_peer_euid (guestfs_h *g, int sock, uid_t *rtn)
 {
+#if CAN_CHECK_PEER_EUID
   struct sockaddr_in peer;
   socklen_t addrlen = sizeof peer;
 
@@ -1805,6 +1835,12 @@ check_peer_euid (guestfs_h *g, int sock, uid_t *rtn)
   error (g, "check_peer_euid: no matching TCP connection found in /proc/net/tcp");
   fclose (fp);
   return -1;
+#else /* !CAN_CHECK_PEER_EUID */
+  /* This function exists but should never be called in this
+   * configuration.
+   */
+  abort ();
+#endif /* !CAN_CHECK_PEER_EUID */
 }
 
 /* You had to call this function after launch in versions <= 1.0.70,
@@ -1832,7 +1868,7 @@ guestfs__kill_subprocess (guestfs_h *g)
   if (g->verbose)
     fprintf (stderr, "sending SIGTERM to process %d\n", g->pid);
 
-  kill (g->pid, SIGTERM);
+  if (g->pid > 0) kill (g->pid, SIGTERM);
   if (g->recoverypid > 0) kill (g->recoverypid, 9);
 
   return 0;
@@ -1983,7 +2019,7 @@ child_cleanup (guestfs_h *g)
   if (g->verbose)
     fprintf (stderr, "child_cleanup: %p: child process died\n", g);
 
-  /*kill (g->pid, SIGTERM);*/
+  /*if (g->pid > 0) kill (g->pid, SIGTERM);*/
   if (g->recoverypid > 0) kill (g->recoverypid, 9);
   waitpid (g->pid, NULL, 0);
   if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
@@ -2350,8 +2386,16 @@ accept_from_daemon (guestfs_h *g)
   int sock = -1;
 
   while (sock == -1) {
+    /* If the qemu process has died, clean up the zombie (RHBZ#579155).
+     * By partially polling in the select below we ensure that this
+     * function will be called eventually.
+     */
+    waitpid (g->pid, NULL, WNOHANG);
+
     rset2 = rset;
-    int r = select (max_fd+1, &rset2, NULL, NULL, NULL);
+
+    struct timeval tv = { .tv_sec = 1, .tv_usec = 0 };
+    int r = select (max_fd+1, &rset2, NULL, NULL, &tv);
     if (r == -1) {
       if (errno == EINTR || errno == EAGAIN)
         continue;