1 /* Socket module header file */
2 
3 /* Includes needed for the sockaddr_* symbols below */
4 #ifndef MS_WINDOWS
5 #ifdef __VMS
6 #   include <socket.h>
7 # else
8 #   include <sys/socket.h>
9 # endif
10 # include <netinet/in.h>
11 # if !(defined(__BEOS__) || defined(__CYGWIN__) || (defined(PYOS_OS2) && defined(PYCC_VACPP)))
12 #  include <netinet/tcp.h>
13 # endif
14 
15 #else /* MS_WINDOWS */
16 # include <winsock2.h>
17 # include <ws2tcpip.h>
18 /* VC6 is shipped with old platform headers, and does not have MSTcpIP.h
19  * Separate SDKs have all the functions we want, but older ones don't have
20  * any version information.
21  * I use SIO_GET_MULTICAST_FILTER to detect a decent SDK.
22  */
23 # ifdef SIO_GET_MULTICAST_FILTER
24 #  include <MSTcpIP.h> /* for SIO_RCVALL */
25 #  define HAVE_ADDRINFO
26 #  define HAVE_SOCKADDR_STORAGE
27 #  define HAVE_GETADDRINFO
28 #  define HAVE_GETNAMEINFO
29 #  define ENABLE_IPV6
30 # else
31 typedef int socklen_t;
32 # endif /* IPPROTO_IPV6 */
33 #endif /* MS_WINDOWS */
34 
35 #ifdef HAVE_SYS_UN_H
36 # include <sys/un.h>
37 #else
38 # undef AF_UNIX
39 #endif
40 
41 #ifdef HAVE_LINUX_NETLINK_H
42 # ifdef HAVE_ASM_TYPES_H
43 #  include <asm/types.h>
44 # endif
45 # include <linux/netlink.h>
46 #else
47 #  undef AF_NETLINK
48 #endif
49 
50 #ifdef HAVE_BLUETOOTH_BLUETOOTH_H
51 #include <bluetooth/bluetooth.h>
52 #include <bluetooth/rfcomm.h>
53 #include <bluetooth/l2cap.h>
54 #include <bluetooth/sco.h>
55 #include <bluetooth/hci.h>
56 #endif
57 
58 #ifdef HAVE_BLUETOOTH_H
59 #include <bluetooth.h>
60 #endif
61 
62 #ifdef HAVE_NETPACKET_PACKET_H
63 # include <sys/ioctl.h>
64 # include <net/if.h>
65 # include <netpacket/packet.h>
66 #endif
67 
68 #ifdef HAVE_LINUX_TIPC_H
69 # include <linux/tipc.h>
70 #endif
71 
72 #ifndef Py__SOCKET_H
73 #define Py__SOCKET_H
74 #ifdef __cplusplus
75 extern "C" {
76 #endif
77 
78 /* Python module and C API name */
79 #define PySocket_MODULE_NAME    "_socket"
80 #define PySocket_CAPI_NAME      "CAPI"
81 #define PySocket_CAPSULE_NAME  (PySocket_MODULE_NAME "." PySocket_CAPI_NAME)
82 
83 /* Abstract the socket file descriptor type */
84 #ifdef MS_WINDOWS
85 typedef SOCKET SOCKET_T;
86 #       ifdef MS_WIN64
87 #               define SIZEOF_SOCKET_T 8
88 #       else
89 #               define SIZEOF_SOCKET_T 4
90 #       endif
91 #else
92 typedef int SOCKET_T;
93 #       define SIZEOF_SOCKET_T SIZEOF_INT
94 #endif
95 
96 /* Socket address */
97 typedef union sock_addr {
98     struct sockaddr_in in;
99 #ifdef AF_UNIX
100     struct sockaddr_un un;
101 #endif
102 #ifdef AF_NETLINK
103     struct sockaddr_nl nl;
104 #endif
105 #ifdef ENABLE_IPV6
106     struct sockaddr_in6 in6;
107     struct sockaddr_storage storage;
108 #endif
109 #ifdef HAVE_BLUETOOTH_BLUETOOTH_H
110     struct sockaddr_l2 bt_l2;
111     struct sockaddr_rc bt_rc;
112     struct sockaddr_sco bt_sco;
113     struct sockaddr_hci bt_hci;
114 #endif
115 #ifdef HAVE_NETPACKET_PACKET_H
116     struct sockaddr_ll ll;
117 #endif
118 } sock_addr_t;
119 
120 /* The object holding a socket.  It holds some extra information,
121    like the address family, which is used to decode socket address
122    arguments properly. */
123 
124 typedef struct {
125     PyObject_HEAD
126     SOCKET_T sock_fd;           /* Socket file descriptor */
127     int sock_family;            /* Address family, e.g., AF_INET */
128     int sock_type;              /* Socket type, e.g., SOCK_STREAM */
129     int sock_proto;             /* Protocol type, usually 0 */
130     PyObject *(*errorhandler)(void); /* Error handler; checks
131                                         errno, returns NULL and
132                                         sets a Python exception */
133     double sock_timeout;                 /* Operation timeout in seconds;
134                                         0.0 means non-blocking */
135     PyObject *weakreflist;
136 } PySocketSockObject;
137 
138 /* --- C API ----------------------------------------------------*/
139 
140 /* Short explanation of what this C API export mechanism does
141    and how it works:
142 
143     The _ssl module needs access to the type object defined in
144     the _socket module. Since cross-DLL linking introduces a lot of
145     problems on many platforms, the "trick" is to wrap the
146     C API of a module in a struct which then gets exported to
147     other modules via a PyCapsule.
148 
149     The code in socketmodule.c defines this struct (which currently
150     only contains the type object reference, but could very
151     well also include other C APIs needed by other modules)
152     and exports it as PyCapsule via the module dictionary
153     under the name "CAPI".
154 
155     Other modules can now include the socketmodule.h file
156     which defines the needed C APIs to import and set up
157     a static copy of this struct in the importing module.
158 
159     After initialization, the importing module can then
160     access the C APIs from the _socket module by simply
161     referring to the static struct, e.g.
162 
163     Load _socket module and its C API; this sets up the global
164     PySocketModule:
165 
166     if (PySocketModule_ImportModuleAndAPI())
167         return;
168 
169 
170     Now use the C API as if it were defined in the using
171     module:
172 
173     if (!PyArg_ParseTuple(args, "O!|zz:ssl",
174 
175                           PySocketModule.Sock_Type,
176 
177                           (PyObject*)&Sock,
178                           &key_file, &cert_file))
179         return NULL;
180 
181     Support could easily be extended to export more C APIs/symbols
182     this way. Currently, only the type object is exported,
183     other candidates would be socket constructors and socket
184     access functions.
185 
186 */
187 
188 /* C API for usage by other Python modules */
189 typedef struct {
190     PyTypeObject *Sock_Type;
191     PyObject *error;
192 } PySocketModule_APIObject;
193 
194 /* XXX The net effect of the following appears to be to define a function
195    XXX named PySocketModule_APIObject in _ssl.c.  It's unclear why it isn't
196    XXX defined there directly.
197 
198    >>> It's defined here because other modules might also want to use
199    >>> the C API.
200 
201 */
202 #ifndef PySocket_BUILDING_SOCKET
203 
204 /* --- C API ----------------------------------------------------*/
205 
206 /* Interfacestructure to C API for other modules.
207    Call PySocketModule_ImportModuleAndAPI() to initialize this
208    structure. After that usage is simple:
209 
210    if (!PyArg_ParseTuple(args, "O!|zz:ssl",
211                          &PySocketModule.Sock_Type, (PyObject*)&Sock,
212                          &key_file, &cert_file))
213      return NULL;
214    ...
215 */
216 
217 static
218 PySocketModule_APIObject PySocketModule;
219 
220 /* You *must* call this before using any of the functions in
221    PySocketModule and check its outcome; otherwise all accesses will
222    result in a segfault. Returns 0 on success. */
223 
224 #ifndef DPRINTF
225 # define DPRINTF if (0) printf
226 #endif
227 
228 static
PySocketModule_ImportModuleAndAPI(void)229 int PySocketModule_ImportModuleAndAPI(void)
230 {
231     void *api;
232 
233   DPRINTF(" Loading capsule %s\n", PySocket_CAPSULE_NAME);
234   api = PyCapsule_Import(PySocket_CAPSULE_NAME, 1);
235     if (api == NULL)
236         goto onError;
237     memcpy(&PySocketModule, api, sizeof(PySocketModule));
238     DPRINTF(" API object loaded and initialized.\n");
239     return 0;
240 
241  onError:
242     DPRINTF(" not found.\n");
243     return -1;
244 }
245 
246 #endif /* !PySocket_BUILDING_SOCKET */
247 
248 #ifdef __cplusplus
249 }
250 #endif
251 #endif /* !Py__SOCKET_H */
252