bpo-31927: Fix bugs in socketmodule.c on NetBSD and other issues. (#4235)

* Fix compilation of the socket module on NetBSD 8.
* Fix the assertion failure or reading arbitrary data when parse
  a AF_BLUETOOTH address on NetBSD and DragonFly BSD.
* Fix other potential errors and make the code more reliable.

3 files changed, 74 insertions, 65 deletions

diff --git a/Misc/NEWS.d/next/Library/2017-11-02-18-26-40.bpo-31927.40K6kp.rst b/Misc/NEWS.d/next/Library/2017-11-02-18-26-40.bpo-31927.40K6kp.rst
new file mode 100644
index 0000000..49f8cdf
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2017-11-02-18-26-40.bpo-31927.40K6kp.rst
@@ -0,0 +1,3 @@
+Fixed compilation of the socket module on NetBSD 8.  Fixed assertion failure
+or reading arbitrary data when parse a AF_BLUETOOTH address on NetBSD and
+DragonFly BSD.
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index 2074fe3..91c879f 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -227,7 +227,7 @@ http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/net/getaddrinfo.c.diff?r1=1.82&
 #endif
 
 
-#if defined(__APPLE__) || defined(__CYGWIN__)
+#if defined(__APPLE__) || defined(__CYGWIN__) || defined(__NetBSD__)
 # include <sys/ioctl.h>
 #endif
 
@@ -1232,7 +1232,7 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
         }
         return ret;
     }
-#endif
+#endif /* ENABLE_IPV6 */
 
 #ifdef USE_BLUETOOTH
     case AF_BLUETOOTH:
@@ -1271,11 +1271,11 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
             struct sockaddr_hci *a = (struct sockaddr_hci *) addr;
 #if defined(__NetBSD__) || defined(__DragonFly__)
             return makebdaddr(&_BT_HCI_MEMB(a, bdaddr));
-#else
+#else /* __NetBSD__ || __DragonFly__ */
             PyObject *ret = NULL;
             ret = Py_BuildValue("i", _BT_HCI_MEMB(a, dev));
             return ret;
-#endif
+#endif /* !(__NetBSD__ || __DragonFly__) */
         }
 
 #if !defined(__FreeBSD__)
@@ -1284,20 +1284,20 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
             struct sockaddr_sco *a = (struct sockaddr_sco *) addr;
             return makebdaddr(&_BT_SCO_MEMB(a, bdaddr));
         }
-#endif
+#endif /* !__FreeBSD__ */
 
         default:
             PyErr_SetString(PyExc_ValueError,
                             "Unknown Bluetooth protocol");
             return NULL;
         }
-#endif
+#endif /* USE_BLUETOOTH */
 
 #if defined(HAVE_NETPACKET_PACKET_H) && defined(SIOCGIFNAME)
     case AF_PACKET:
     {
         struct sockaddr_ll *a = (struct sockaddr_ll *)addr;
-        char *ifname = "";
+        const char *ifname = "";
         struct ifreq ifr;
         /* need to look up interface name give index */
         if (a->sll_ifindex) {
@@ -1313,7 +1313,7 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
                              a->sll_addr,
                              a->sll_halen);
     }
-#endif
+#endif /* HAVE_NETPACKET_PACKET_H && SIOCGIFNAME */
 
 #ifdef HAVE_LINUX_TIPC_H
     case AF_TIPC:
@@ -1346,13 +1346,13 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
             return NULL;
         }
     }
-#endif
+#endif /* HAVE_LINUX_TIPC_H */
 
-#ifdef AF_CAN
+#if defined(AF_CAN) && defined(SIOCGIFNAME)
     case AF_CAN:
     {
         struct sockaddr_can *a = (struct sockaddr_can *)addr;
-        char *ifname = "";
+        const char *ifname = "";
         struct ifreq ifr;
         /* need to look up interface name given index */
         if (a->can_ifindex) {
@@ -1370,7 +1370,7 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
                                           a->can_addr.tp.rx_id,
                                           a->can_addr.tp.tx_id);
           }
-#endif
+#endif /* CAN_ISOTP */
           default:
           {
               return Py_BuildValue("O&", PyUnicode_DecodeFSDefault,
@@ -1378,7 +1378,7 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
           }
         }
     }
-#endif
+#endif /* AF_CAN && SIOCGIFNAME */
 
 #ifdef PF_SYSTEM
     case PF_SYSTEM:
@@ -1389,13 +1389,13 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
             struct sockaddr_ctl *a = (struct sockaddr_ctl *)addr;
             return Py_BuildValue("(II)", a->sc_id, a->sc_unit);
         }
-#endif
+#endif /* SYSPROTO_CONTROL */
         default:
             PyErr_SetString(PyExc_ValueError,
                             "Invalid address type");
             return 0;
         }
-#endif
+#endif /* PF_SYSTEM */
 
 #ifdef HAVE_SOCKADDR_ALG
     case AF_ALG:
@@ -1411,7 +1411,7 @@ makesockaddr(SOCKET_T sockfd, struct sockaddr *addr, size_t addrlen, int proto)
             a->salg_feat,
             a->salg_mask);
     }
-#endif
+#endif /* HAVE_SOCKADDR_ALG */
 
     /* More cases here... */
 
@@ -1577,7 +1577,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         *len_ret = sizeof(*addr);
         return 1;
     }
-#endif
+#endif /* AF_NETLINK */
 
 #if defined(AF_VSOCK)
     case AF_VSOCK:
@@ -1602,13 +1602,13 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         *len_ret = sizeof(*addr);
         return 1;
     }
-#endif
+#endif /* AF_VSOCK */
 
 
 #ifdef AF_RDS
     case AF_RDS:
         /* RDS sockets use sockaddr_in: fall-through */
-#endif
+#endif /* AF_RDS */
 
     case AF_INET:
     {
@@ -1690,7 +1690,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         *len_ret = sizeof *addr;
         return 1;
     }
-#endif
+#endif /* ENABLE_IPV6 */
 
 #ifdef USE_BLUETOOTH
     case AF_BLUETOOTH:
@@ -1699,7 +1699,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         case BTPROTO_L2CAP:
         {
             struct sockaddr_l2 *addr;
-            char *straddr;
+            const char *straddr;
 
             addr = (struct sockaddr_l2 *)addr_ret;
             memset(addr, 0, sizeof(struct sockaddr_l2));
@@ -1719,7 +1719,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         case BTPROTO_RFCOMM:
         {
             struct sockaddr_rc *addr;
-            char *straddr;
+            const char *straddr;
 
             addr = (struct sockaddr_rc *)addr_ret;
             _BT_RC_MEMB(addr, family) = AF_BLUETOOTH;
@@ -1739,24 +1739,24 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         {
             struct sockaddr_hci *addr = (struct sockaddr_hci *)addr_ret;
 #if defined(__NetBSD__) || defined(__DragonFly__)
-                        char *straddr = PyBytes_AS_STRING(args);
-
-                        _BT_HCI_MEMB(addr, family) = AF_BLUETOOTH;
-            if (straddr == NULL) {
+            const char *straddr;
+            _BT_HCI_MEMB(addr, family) = AF_BLUETOOTH;
+            if (!PyBytes_Check(args)) {
                 PyErr_SetString(PyExc_OSError, "getsockaddrarg: "
                     "wrong format");
                 return 0;
             }
+            straddr = PyBytes_AS_STRING(args);
             if (setbdaddr(straddr, &_BT_HCI_MEMB(addr, bdaddr)) < 0)
                 return 0;
-#else
+#else  /* __NetBSD__ || __DragonFly__ */
             _BT_HCI_MEMB(addr, family) = AF_BLUETOOTH;
             if (!PyArg_ParseTuple(args, "i", &_BT_HCI_MEMB(addr, dev))) {
                 PyErr_SetString(PyExc_OSError, "getsockaddrarg: "
                                 "wrong format");
                 return 0;
             }
-#endif
+#endif /* !(__NetBSD__ || __DragonFly__) */
             *len_ret = sizeof *addr;
             return 1;
         }
@@ -1764,7 +1764,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         case BTPROTO_SCO:
         {
             struct sockaddr_sco *addr;
-            char *straddr;
+            const char *straddr;
 
             addr = (struct sockaddr_sco *)addr_ret;
             _BT_SCO_MEMB(addr, family) = AF_BLUETOOTH;
@@ -1780,20 +1780,20 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
             *len_ret = sizeof *addr;
             return 1;
         }
-#endif
+#endif /* !__FreeBSD__ */
         default:
             PyErr_SetString(PyExc_OSError, "getsockaddrarg: unknown Bluetooth protocol");
             return 0;
         }
     }
-#endif
+#endif /* USE_BLUETOOTH */
 
 #if defined(HAVE_NETPACKET_PACKET_H) && defined(SIOCGIFINDEX)
     case AF_PACKET:
     {
         struct sockaddr_ll* addr;
         struct ifreq ifr;
-        char *interfaceName;
+        const char *interfaceName;
         int protoNumber;
         int hatype = 0;
         int pkttype = 0;
@@ -1847,7 +1847,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         PyBuffer_Release(&haddr);
         return 1;
     }
-#endif
+#endif /* HAVE_NETPACKET_PACKET_H && SIOCGIFINDEX */
 
 #ifdef HAVE_LINUX_TIPC_H
     case AF_TIPC:
@@ -1897,16 +1897,19 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
 
         return 1;
     }
-#endif
-
-#ifdef AF_CAN
+#endif /* HAVE_LINUX_TIPC_H */
 
-#if defined(CAN_RAW) && defined(CAN_BCM)
+#if defined(AF_CAN) && defined(SIOCGIFINDEX)
     case AF_CAN:
         switch (s->sock_proto) {
+#ifdef CAN_RAW
         case CAN_RAW:
         /* fall-through */
+#endif
+#ifdef CAN_BCM
         case CAN_BCM:
+#endif
+#if defined(CAN_RAW) || defined(CAN_BCM)
         {
             struct sockaddr_can *addr;
             PyObject *interfaceName;
@@ -1944,7 +1947,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
             Py_DECREF(interfaceName);
             return 1;
         }
-#endif
+#endif /* CAN_RAW || CAN_BCM */
 
 #ifdef CAN_ISOTP
         case CAN_ISOTP:
@@ -1991,13 +1994,13 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
             Py_DECREF(interfaceName);
             return 1;
         }
-#endif
+#endif /* CAN_ISOTP */
         default:
             PyErr_SetString(PyExc_OSError,
                             "getsockaddrarg: unsupported CAN protocol");
             return 0;
         }
-#endif
+#endif /* AF_CAN && SIOCGIFINDEX */
 
 #ifdef PF_SYSTEM
     case PF_SYSTEM:
@@ -2049,19 +2052,19 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
             *len_ret = sizeof(*addr);
             return 1;
         }
-#endif
+#endif /* SYSPROTO_CONTROL */
         default:
             PyErr_SetString(PyExc_OSError,
                             "getsockaddrarg: unsupported PF_SYSTEM protocol");
             return 0;
         }
-#endif
+#endif /* PF_SYSTEM */
 #ifdef HAVE_SOCKADDR_ALG
     case AF_ALG:
     {
         struct sockaddr_alg *sa;
-        char *type;
-        char *name;
+        const char *type;
+        const char *name;
         sa = (struct sockaddr_alg *)addr_ret;
 
         memset(sa, 0, sizeof(*sa));
@@ -2085,7 +2088,7 @@ getsockaddrarg(PySocketSockObject *s, PyObject *args,
         *len_ret = sizeof(*sa);
         return 1;
     }
-#endif
+#endif /* HAVE_SOCKADDR_ALG */
 
     /* More cases here... */
 
@@ -2120,7 +2123,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         *len_ret = sizeof (struct sockaddr_nl);
         return 1;
     }
-#endif
+#endif /* AF_NETLINK */
 
 #if defined(AF_VSOCK)
        case AF_VSOCK:
@@ -2128,12 +2131,12 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
            *len_ret = sizeof (struct sockaddr_vm);
            return 1;
        }
-#endif
+#endif /* AF_VSOCK */
 
 #ifdef AF_RDS
     case AF_RDS:
         /* RDS sockets use sockaddr_in: fall-through */
-#endif
+#endif /* AF_RDS */
 
     case AF_INET:
     {
@@ -2147,7 +2150,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         *len_ret = sizeof (struct sockaddr_in6);
         return 1;
     }
-#endif
+#endif /* ENABLE_IPV6 */
 
 #ifdef USE_BLUETOOTH
     case AF_BLUETOOTH:
@@ -2168,7 +2171,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         case BTPROTO_SCO:
             *len_ret = sizeof (struct sockaddr_sco);
             return 1;
-#endif
+#endif /* !__FreeBSD__ */
         default:
             PyErr_SetString(PyExc_OSError, "getsockaddrlen: "
                             "unknown BT protocol");
@@ -2176,7 +2179,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
 
         }
     }
-#endif
+#endif /* USE_BLUETOOTH */
 
 #ifdef HAVE_NETPACKET_PACKET_H
     case AF_PACKET:
@@ -2184,7 +2187,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         *len_ret = sizeof (struct sockaddr_ll);
         return 1;
     }
-#endif
+#endif /* HAVE_NETPACKET_PACKET_H */
 
 #ifdef HAVE_LINUX_TIPC_H
     case AF_TIPC:
@@ -2192,7 +2195,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         *len_ret = sizeof (struct sockaddr_tipc);
         return 1;
     }
-#endif
+#endif /* HAVE_LINUX_TIPC_H */
 
 #ifdef AF_CAN
     case AF_CAN:
@@ -2200,7 +2203,7 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         *len_ret = sizeof (struct sockaddr_can);
         return 1;
     }
-#endif
+#endif /* AF_CAN */
 
 #ifdef PF_SYSTEM
     case PF_SYSTEM:
@@ -2209,20 +2212,20 @@ getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
         case SYSPROTO_CONTROL:
             *len_ret = sizeof (struct sockaddr_ctl);
             return 1;
-#endif
+#endif /* SYSPROTO_CONTROL */
         default:
             PyErr_SetString(PyExc_OSError, "getsockaddrlen: "
                             "unknown PF_SYSTEM protocol");
             return 0;
         }
-#endif
+#endif /* PF_SYSTEM */
 #ifdef HAVE_SOCKADDR_ALG
     case AF_ALG:
     {
         *len_ret = sizeof (struct sockaddr_alg);
         return 1;
     }
-#endif
+#endif /* HAVE_SOCKADDR_ALG */
 
     /* More cases here... */
 
@@ -5288,7 +5291,7 @@ socket_gethostbyaddr(PyObject *self, PyObject *args)
     int result;
 #endif
 #endif /* HAVE_GETHOSTBYNAME_R */
-    char *ap;
+    const char *ap;
     int al;
     int af;
 
@@ -5361,7 +5364,7 @@ for a host.  The host argument is a string giving a host name or IP number.");
 static PyObject *
 socket_getservbyname(PyObject *self, PyObject *args)
 {
-    char *name, *proto=NULL;
+    const char *name, *proto=NULL;
     struct servent *sp;
     if (!PyArg_ParseTuple(args, "s|s:getservbyname", &name, &proto))
         return NULL;
@@ -5392,7 +5395,7 @@ static PyObject *
 socket_getservbyport(PyObject *self, PyObject *args)
 {
     int port;
-    char *proto=NULL;
+    const char *proto=NULL;
     struct servent *sp;
     if (!PyArg_ParseTuple(args, "i|s:getservbyport", &port, &proto))
         return NULL;
@@ -5427,7 +5430,7 @@ otherwise any protocol will match.");
 static PyObject *
 socket_getprotobyname(PyObject *self, PyObject *args)
 {
-    char *name;
+    const char *name;
     struct protoent *sp;
     if (!PyArg_ParseTuple(args, "s:getprotobyname", &name))
         return NULL;
@@ -5753,7 +5756,7 @@ socket_inet_aton(PyObject *self, PyObject *args)
     /* Have to use inet_addr() instead */
     unsigned int packed_addr;
 #endif
-    char *ip_addr;
+    const char *ip_addr;
 
     if (!PyArg_ParseTuple(args, "s:inet_aton", &ip_addr))
         return NULL;
@@ -5846,7 +5849,7 @@ static PyObject *
 socket_inet_pton(PyObject *self, PyObject *args)
 {
     int af;
-    char* ip;
+    const char* ip;
     int retval;
 #ifdef ENABLE_IPV6
     char packed[Py_MAX(sizeof(struct in_addr), sizeof(struct in6_addr))];
@@ -6076,7 +6079,7 @@ socket_getnameinfo(PyObject *self, PyObject *args)
 {
     PyObject *sa = (PyObject *)NULL;
     int flags;
-    char *hostp;
+    const char *hostp;
     int port;
     unsigned int flowinfo, scope_id;
     char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
diff --git a/Modules/socketmodule.h b/Modules/socketmodule.h
index e0d50df..fdb4e87 100644
--- a/Modules/socketmodule.h
+++ b/Modules/socketmodule.h
@@ -80,7 +80,10 @@ typedef int socklen_t;
 #endif
 
 #ifdef HAVE_LINUX_CAN_H
-#include <linux/can.h>
+# include <linux/can.h>
+#else
+# undef AF_CAN
+# undef PF_CAN
 #endif
 
 #ifdef HAVE_LINUX_CAN_RAW_H