Use fstat to check if descriptor 0 is a socket.

Suggested by: julian

4 files changed, 102 insertions, 61 deletions

diff --git a/usr.sbin/ppp/ether.c b/usr.sbin/ppp/ether.c
index cf9c999..e3ab77f 100644
--- a/usr.sbin/ppp/ether.c
+++ b/usr.sbin/ppp/ether.c
@@ -51,6 +51,7 @@
 #include <sys/linker.h>
 #include <sys/module.h>
 #endif
+#include <sys/stat.h>
 #include <sys/uio.h>
 #include <termios.h>
 #include <sys/time.h>
@@ -623,29 +624,40 @@ ether_Create(struct physical *p)
 
   } else {
     /* See if we're a netgraph socket */
-    struct sockaddr_ng ngsock;
-    struct sockaddr *sock = (struct sockaddr *)&ngsock;
-    int sz;
-
-    sz = sizeof ngsock;
-    if (getsockname(p->fd, sock, &sz) != -1 && sock->sa_family == AF_NETGRAPH) {
-      /*
-       * It's a netgraph node... We can't determine hook names etc, so we
-       * stay pretty impartial....
-       */
-      log_Printf(LogPHASE, "%s: Link is a netgraph node\n", p->link.name);
-
-      if ((dev = malloc(sizeof *dev)) == NULL) {
-        log_Printf(LogWARN, "%s: Cannot allocate an ether device: %s\n",
-                   p->link.name, strerror(errno));
+    struct stat st;
+
+    if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
+      struct sockaddr_storage ssock;
+      struct sockaddr *sock = (struct sockaddr *)&ssock;
+      int sz;
+
+      sz = sizeof ssock;
+      if (getsockname(p->fd, sock, &sz) == -1) {
+        log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
+        close(p->fd);
+        p->fd = -1;
         return NULL;
       }
 
-      memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
-      dev->cs = -1;
-      dev->timeout = 0;
-      dev->connected = CARRIER_OK;
-      *dev->hook = '\0';
+      if (sock->sa_family == AF_NETGRAPH) {
+        /*
+         * It's a netgraph node... We can't determine hook names etc, so we
+         * stay pretty impartial....
+         */
+        log_Printf(LogPHASE, "%s: Link is a netgraph node\n", p->link.name);
+
+        if ((dev = malloc(sizeof *dev)) == NULL) {
+          log_Printf(LogWARN, "%s: Cannot allocate an ether device: %s\n",
+                     p->link.name, strerror(errno));
+          return NULL;
+        }
+
+        memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
+        dev->cs = -1;
+        dev->timeout = 0;
+        dev->connected = CARRIER_OK;
+        *dev->hook = '\0';
+      }
     }
   }
 
diff --git a/usr.sbin/ppp/physical.c b/usr.sbin/ppp/physical.c
index 3d7811f..5e50224 100644
--- a/usr.sbin/ppp/physical.c
+++ b/usr.sbin/ppp/physical.c
@@ -119,15 +119,22 @@ struct {
   int (*DeviceSize)(void);
 } devices[] = {
 #ifndef NOI4B
+  /*
+   * This must come before ``tty'' so that the probe routine is
+   * able to identify it as a more specific type of terminal device.
+   */
   { i4b_Create, i4b_iov2device, i4b_DeviceSize },
 #endif
   { tty_Create, tty_iov2device, tty_DeviceSize },
 #ifndef NONETGRAPH
-  /* This must come before ``udp'' & ``tcp'' */
+  /*
+   * This must come before ``udp'' so that the probe routine is
+   * able to identify it as a more specific type of SOCK_DGRAM.
+   */
   { ether_Create, ether_iov2device, ether_DeviceSize },
 #endif
 #ifndef NOATM
-  /* and so must this */
+  /* Ditto for ATM devices */
   { atm_Create, atm_iov2device, atm_DeviceSize },
 #endif
   { tcp_Create, tcp_iov2device, tcp_DeviceSize },
diff --git a/usr.sbin/ppp/tcp.c b/usr.sbin/ppp/tcp.c
index 72d6eb1..b7482d1 100644
--- a/usr.sbin/ppp/tcp.c
+++ b/usr.sbin/ppp/tcp.c
@@ -36,6 +36,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 #include <sys/uio.h>
 #include <termios.h>
 #include <unistd.h>
@@ -164,33 +165,43 @@ tcp_Create(struct physical *p)
 
   if (p->fd >= 0) {
     /* See if we're a tcp socket */
-    int type, sz, err;
-
-    sz = sizeof type;
-    if ((err = getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz)) == 0 &&
-        sz == sizeof type && type == SOCK_STREAM) {
-      struct sockaddr_in sock;
-      struct sockaddr *sockp = (struct sockaddr *)&sock;
-
-      if (*p->name.full == '\0') {
-        sz = sizeof sock;
-        if (getpeername(p->fd, sockp, &sz) != 0 ||
-            sz != sizeof(struct sockaddr_in) || sock.sin_family != AF_INET) {
-          log_Printf(LogDEBUG, "%s: Link is SOCK_STREAM, but not inet\n",
-                     p->link.name);
-          return NULL;
-        }
+    struct stat st;
+
+    if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
+      int type, sz;
+
+      sz = sizeof type;
+      if (getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz) == -1) {
+        log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
+        close(p->fd);
+        p->fd = -1;
+        return NULL;
+      }
 
-        log_Printf(LogPHASE, "%s: Link is a tcp socket\n", p->link.name);
+      if (sz == sizeof type && type == SOCK_STREAM) {
+        struct sockaddr_in sock;
+        struct sockaddr *sockp = (struct sockaddr *)&sock;
 
-        snprintf(p->name.full, sizeof p->name.full, "%s:%d/tcp",
-                 inet_ntoa(sock.sin_addr), ntohs(sock.sin_port));
-        p->name.base = p->name.full;
+        if (*p->name.full == '\0') {
+          sz = sizeof sock;
+          if (getpeername(p->fd, sockp, &sz) != 0 ||
+              sz != sizeof(struct sockaddr_in) || sock.sin_family != AF_INET) {
+            log_Printf(LogDEBUG, "%s: Link is SOCK_STREAM, but not inet\n",
+                       p->link.name);
+            return NULL;
+          }
+
+          log_Printf(LogPHASE, "%s: Link is a tcp socket\n", p->link.name);
+
+          snprintf(p->name.full, sizeof p->name.full, "%s:%d/tcp",
+                   inet_ntoa(sock.sin_addr), ntohs(sock.sin_port));
+          p->name.base = p->name.full;
+        }
+        physical_SetupStack(p, tcpdevice.name, PHYSICAL_FORCE_ASYNC);
+        if (p->cfg.cd.necessity != CD_DEFAULT)
+          log_Printf(LogWARN, "Carrier settings ignored\n");
+        return &tcpdevice;
       }
-      physical_SetupStack(p, tcpdevice.name, PHYSICAL_FORCE_ASYNC);
-      if (p->cfg.cd.necessity != CD_DEFAULT)
-        log_Printf(LogWARN, "Carrier settings ignored\n");
-      return &tcpdevice;
     }
   }
 
diff --git a/usr.sbin/ppp/udp.c b/usr.sbin/ppp/udp.c
index 7334f59..6894e1e 100644
--- a/usr.sbin/ppp/udp.c
+++ b/usr.sbin/ppp/udp.c
@@ -37,6 +37,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sysexits.h>
+#include <sys/stat.h>
 #include <sys/uio.h>
 #include <termios.h>
 #include <unistd.h>
@@ -277,26 +278,36 @@ udp_Create(struct physical *p)
     }
   } else {
     /* See if we're a connected udp socket */
-    int type, sz, err;
-
-    sz = sizeof type;
-    if ((err = getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz)) == 0 &&
-        sz == sizeof type && type == SOCK_DGRAM) {
-      if ((dev = malloc(sizeof *dev)) == NULL) {
-        log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
-                   p->link.name, strerror(errno));
+    struct stat st;
+
+    if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
+      int type, sz;
+
+      sz = sizeof type;
+      if (getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz) == -1) {
+        log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
+        close(p->fd);
+        p->fd = -1;
         return NULL;
       }
 
-      /* We can't getpeername().... */
-      dev->connected = UDP_MAYBEUNCONNECTED;
+      if (sz == sizeof type && type == SOCK_DGRAM) {
+        if ((dev = malloc(sizeof *dev)) == NULL) {
+          log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
+                     p->link.name, strerror(errno));
+          return NULL;
+        }
+
+        /* We can't getpeername().... */
+        dev->connected = UDP_MAYBEUNCONNECTED;
 
-      log_Printf(LogPHASE, "%s: Link is a udp socket\n", p->link.name);
+        log_Printf(LogPHASE, "%s: Link is a udp socket\n", p->link.name);
 
-      if (p->link.lcp.cfg.openmode != OPEN_PASSIVE) {
-        log_Printf(LogPHASE, "%s:   Changing openmode to PASSIVE\n",
-                   p->link.name);
-        p->link.lcp.cfg.openmode = OPEN_PASSIVE;
+        if (p->link.lcp.cfg.openmode != OPEN_PASSIVE) {
+          log_Printf(LogPHASE, "%s:   Changing openmode to PASSIVE\n",
+                     p->link.name);
+          p->link.lcp.cfg.openmode = OPEN_PASSIVE;
+        }
       }
     }
   }