dbus-monitor: more details on file descriptors

Print more details when receiving a file descriptor.

Before:
   unix fd 5

After:
   file descriptor
         inode: 1030
         type: char
   file descriptor
         inode: 295664
         type: socket
         address family: unknown (16)
   file descriptor
         inode: 295665
         type: socket
         address family: inet
         name 127.0.0.1 port 47723
         peer 127.0.0.1 port 22
   file descriptor
         inode: 295666
         type: socket
         address family: unix
         name @/tmp/d67s774Sws0pEra
   file descriptor
         inode: 295667
         type: socket
         address family: unix
         name @
         peer @

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=80603
Reviewed-by: Simon McVittie <simon.mcvittie@collabora.co.uk>

1 files changed, 158 insertions, 1 deletions

diff --git a/tools/dbus-print-message.c b/tools/dbus-print-message.c
index 320abd6f..6f02ea38 100644
--- a/tools/dbus-print-message.c
+++ b/tools/dbus-print-message.c
@@ -23,6 +23,17 @@
 #include <config.h>
 #include "dbus-print-message.h"
 
+#ifdef DBUS_UNIX
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#endif
+
 #include <stdlib.h>
 #include "config.h"
 
@@ -143,6 +154,151 @@ print_ay (DBusMessageIter *iter, int depth)
 }
 
 static void
+print_fd (int fd, int depth)
+{
+#ifdef DBUS_UNIX
+  int ret;
+  struct stat statbuf = {0,};
+  union {
+      struct sockaddr sa;
+      struct sockaddr_storage storage;
+      struct sockaddr_un un;
+      struct sockaddr_in ipv4;
+      struct sockaddr_in6 ipv6;
+  } addr, peer;
+  char hostip[INET6_ADDRSTRLEN];
+  int addrlen = sizeof (addr);
+  int peerlen = sizeof (peer);
+  int has_peer;
+#endif
+
+  /* Don't print the fd number: it is different in every process and since
+   * dbus-monitor closes the fd after reading it, the same number would be
+   * printed again and again.
+   */
+  printf ("file descriptor\n");
+  if (fd == -1)
+    return;
+
+#ifdef DBUS_UNIX
+  ret = fstat (fd, &statbuf);
+  if (ret == -1)
+    return;
+
+  indent (depth+1);
+  printf ("inode: %d\n", (int) statbuf.st_ino);
+
+  indent (depth+1);
+  printf ("type: ");
+  if (S_ISREG(statbuf.st_mode))
+    printf ("file\n");
+  if (S_ISDIR(statbuf.st_mode))
+    printf ("directory\n");
+  if (S_ISCHR(statbuf.st_mode))
+    printf ("char\n");
+  if (S_ISBLK(statbuf.st_mode))
+    printf ("block\n");
+  if (S_ISFIFO(statbuf.st_mode))
+    printf ("fifo\n");
+  if (S_ISLNK(statbuf.st_mode))
+    printf ("link\n");
+  if (S_ISSOCK(statbuf.st_mode))
+    printf ("socket\n");
+
+  /* If it's not a socket, getsockname will just return -1 with errno
+   * ENOTSOCK. */
+
+  memset (&addr, 0, sizeof (addr));
+  memset (&peer, 0, sizeof (peer));
+
+  if (getsockname(fd, &addr.sa, &addrlen))
+    return;
+
+  has_peer = !getpeername(fd, &peer.sa, &peerlen);
+
+  indent (depth+1);
+  printf ("address family: ");
+  switch (addr.sa.sa_family)
+    {
+      case AF_UNIX:
+        printf("unix\n");
+        if (addr.un.sun_path[0] == '\0')
+          {
+            /* Abstract socket might not be zero-terminated and length is
+             * variable. Who designed this interface?
+             * Write the name in the same way as /proc/net/unix
+             * See manual page unix(7)
+             */
+            indent (depth+1);
+            printf ("name @%.*s\n",
+                    (int) (addrlen - sizeof (sa_family_t) - 1),
+                    &(addr.un.sun_path[1]));
+
+            if (has_peer)
+              {
+                indent (depth+1);
+                printf ("peer @%.*s\n",
+                        (int) (addrlen - sizeof (sa_family_t) - 1),
+                        &(addr.un.sun_path[1]));
+              }
+          }
+        else
+          {
+            indent (depth+1);
+            printf ("name %s\n", addr.un.sun_path);
+            if (has_peer)
+              {
+                indent (depth+1);
+                printf ("peer %s\n", peer.un.sun_path);
+              }
+          }
+        break;
+
+      case AF_INET:
+        printf ("inet\n");
+        if (inet_ntop (AF_INET, &addr.ipv4.sin_addr, hostip, sizeof (hostip)))
+          {
+            indent (depth+1);
+            printf ("name %s port %u\n", hostip, ntohs (addr.ipv4.sin_port));
+          }
+        if (has_peer && inet_ntop (AF_INET, &peer.ipv4.sin_addr, hostip, sizeof (hostip)))
+          {
+            indent (depth+1);
+            printf ("peer %s port %u\n", hostip, ntohs (peer.ipv4.sin_port));
+          }
+
+        break;
+
+#ifdef AF_INET6
+      case AF_INET6:
+        printf ("inet6\n");
+        if (inet_ntop (AF_INET6, &addr.ipv6.sin6_addr, hostip, sizeof (hostip)))
+          {
+            indent (depth+1);
+            printf ("name %s port %u\n", hostip, ntohs (addr.ipv6.sin6_port));
+          }
+        if (has_peer && inet_ntop (AF_INET6, &peer.ipv6.sin6_addr, hostip, sizeof (hostip)))
+          {
+            indent (depth+1);
+            printf ("peer %s port %u\n", hostip, ntohs (peer.ipv6.sin6_port));
+          }
+        break;
+#endif
+
+#ifdef AF_BLUETOOTH
+      case AF_BLUETOOTH:
+        printf ("bluetooth\n");
+        break;
+#endif
+
+      default:
+        printf ("unknown (%d)\n", addr.sa.sa_family);
+        break;
+    }
+#endif
+}
+
+static void
 print_iter (DBusMessageIter *iter, dbus_bool_t literal, int depth)
 {
   do
@@ -351,7 +507,8 @@ print_iter (DBusMessageIter *iter, dbus_bool_t literal, int depth)
 	  {
 	    int fd;
 	    dbus_message_iter_get_basic (iter, &fd);
-	    printf ("unix fd %d\n", fd);
+
+	    print_fd (fd, depth+1);
 
             /* dbus_message_iter_get_basic() duplicated the fd, we need to
              * close it after use. The original fd will be closed when the