GNUnet  0.10.x
nat_api_stun.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2009, 2015, 2016 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
10  GNUnet is distributed in the hope that it will be useful, but
11  WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
38 #include "platform.h"
39 #include "gnunet_util_lib.h"
41 #include "gnunet_nat_service.h"
42 
43 
44 #include "nat_stun.h"
45 
46 #define LOG(kind, ...) GNUNET_log_from(kind, "stun", __VA_ARGS__)
47 
48 #define TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 15)
49 
50 
61 
66 
70  char *stun_server;
71 
76 
80  void *cb_cls;
81 
86 
90  uint16_t stun_port;
91 };
92 
93 
101 static int
103  enum StunMethods method)
104 {
105  return ((msg_class & 1) << 4) | ((msg_class & 2) << 7) |
106  (method & 0x000f) | ((method & 0x0070) << 1) | ((method & 0x0f800) << 2);
107 }
108 
109 
115 static void
117 {
118  req->magic = htonl(STUN_MAGIC_COOKIE);
119  for (unsigned int x = 0; x < 3; x++)
121  UINT32_MAX);
122 }
123 
124 
132 static void
134  const struct sockaddr *addr,
135  socklen_t addrlen)
136 {
137  struct GNUNET_NAT_STUN_Handle *rh = cls;
138  struct stun_header req;
139  struct sockaddr_in server;
140 
141  if (NULL == addr)
142  {
143  rh->dns_active = NULL;
144  if (GNUNET_NO == rh->dns_success)
145  {
147  "Error resolving host %s\n",
148  rh->stun_server);
149  rh->cb(rh->cb_cls,
151  }
152  else if (GNUNET_SYSERR == rh->dns_success)
153  {
154  rh->cb(rh->cb_cls,
156  }
157  else
158  {
159  rh->cb(rh->cb_cls,
161  }
163  return;
164  }
165 
166  rh->dns_success = GNUNET_YES;
167  memset(&server, 0, sizeof(server));
168  server.sin_family = AF_INET;
169  server.sin_addr = ((struct sockaddr_in *)addr)->sin_addr;
170  server.sin_port = htons(rh->stun_port);
171 #if HAVE_SOCKADDR_IN_SIN_LEN
172  server.sin_len = (u_char)sizeof(struct sockaddr_in);
173 #endif
174 
175  /* Craft the simplest possible STUN packet. A request binding */
176  generate_request_id(&req);
177  req.msglen = htons(0);
178  req.msgtype = htons(encode_message(STUN_REQUEST,
179  STUN_BINDING));
180 
181  /* Send the packet */
182  if (-1 ==
184  &req,
185  sizeof(req),
186  (const struct sockaddr *)&server,
187  sizeof(server)))
188  {
190  "sendto");
192  return;
193  }
194 }
195 
196 
208 struct GNUNET_NAT_STUN_Handle *
209 GNUNET_NAT_stun_make_request(const char *server,
210  uint16_t port,
211  struct GNUNET_NETWORK_Handle *sock,
213  void *cb_cls)
214 {
215  struct GNUNET_NAT_STUN_Handle *rh;
216 
217  rh = GNUNET_new(struct GNUNET_NAT_STUN_Handle);
218  rh->sock = sock;
219  rh->cb = cb;
220  rh->cb_cls = cb_cls;
221  rh->stun_server = GNUNET_strdup(server);
222  rh->stun_port = port;
223  rh->dns_success = GNUNET_NO;
225  AF_INET,
226  TIMEOUT,
228  rh);
229  if (NULL == rh->dns_active)
230  {
232  return NULL;
233  }
234  return rh;
235 }
236 
237 
244 void
246 {
247  if (NULL != rh->dns_active)
248  {
250  rh->dns_active = NULL;
251  }
253  GNUNET_free(rh);
254 }
255 
256 
257 /* end of nat_stun.c */
void GNUNET_RESOLVER_request_cancel(struct GNUNET_RESOLVER_RequestHandle *rh)
Cancel a request that is still pending with the resolver.
struct GNUNET_NAT_STUN_Handle * GNUNET_NAT_stun_make_request(const char *server, uint16_t port, struct GNUNET_NETWORK_Handle *sock, GNUNET_NAT_TestCallback cb, void *cb_cls)
Make Generic STUN request.
Definition: nat_api_stun.c:209
detected that we are offline
void GNUNET_NAT_stun_make_request_cancel(struct GNUNET_NAT_STUN_Handle *rh)
Cancel active STUN request.
Definition: nat_api_stun.c:245
void * cb_cls
Closure for cb.
Definition: nat_api_stun.c:80
uint32_t GNUNET_CRYPTO_random_u32(enum GNUNET_CRYPTO_Quality mode, uint32_t i)
Produce a random value.
Handle to a request given to the resolver.
Definition: nat_api_stun.c:56
Message types for STUN server resolution.
stun_trans_id id
Definition: nat_stun.h:45
void(* GNUNET_NAT_TestCallback)(void *cls, enum GNUNET_NAT_StatusCode result)
Function called to report success or failure for NAT configuration test.
#define GNUNET_NO
Definition: gnunet_common.h:78
struct GNUNET_RESOLVER_RequestHandle * GNUNET_RESOLVER_ip_get(const char *hostname, int af, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_AddressCallback callback, void *callback_cls)
Convert a string to one or more IP addresses.
Definition: resolver_api.c:933
#define GNUNET_new(type)
Allocate a struct or union of the given type.
uint16_t msglen
Definition: nat_stun.h:43
#define GNUNET_strdup(a)
Wrapper around GNUNET_xstrdup_.
StunMethods
Definition: nat_stun.h:89
#define GNUNET_log_strerror(level, cmd)
Log an error message at log-level &#39;level&#39; that indicates a failure of the command &#39;cmd&#39; with the mess...
#define LOG(kind,...)
Definition: nat_api_stun.c:46
ssize_t GNUNET_NETWORK_socket_sendto(const struct GNUNET_NETWORK_Handle *desc, const void *message, size_t length, const struct sockaddr *dest_addr, socklen_t dest_len)
Send data to a particular destination (always non-blocking).
Definition: network.c:838
Randomness for IVs etc.
uint16_t msgtype
Definition: nat_stun.h:42
struct GNUNET_NETWORK_Handle * sock
Handle to the listen socket.
Definition: nat_api_stun.c:65
Failure in network subsystem, check permissions.
char * stun_server
Stun server address.
Definition: nat_api_stun.c:70
struct sockaddr * addr
Address we were bound to, or NULL.
Definition: network.c:67
#define TIMEOUT
Definition: nat_api_stun.c:48
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
GNUNET_NAT_TestCallback cb
Function to call when a error occours.
Definition: nat_api_stun.c:75
Handle to a request given to the resolver.
Definition: resolver_api.c:100
static int encode_message(enum StunClasses msg_class, enum StunMethods method)
Encode a class and method to a compatible STUN format.
Definition: nat_api_stun.c:102
StunClasses
STUN message classes.
Definition: nat_stun.h:81
uint16_t stun_port
STUN port.
Definition: nat_api_stun.c:90
int dns_success
Do we got a DNS resolution successfully?
Definition: nat_api_stun.c:85
static uint16_t port
Port number.
Definition: gnunet-bcd.c:81
socklen_t addrlen
Number of bytes in addr.
Definition: network.c:62
#define STUN_MAGIC_COOKIE
Definition: nat_stun.h:34
static void stun_dns_callback(void *cls, const struct sockaddr *addr, socklen_t addrlen)
Try to establish a connection given the specified address.
Definition: nat_api_stun.c:133
handle to a socket
Definition: network.c:46
uint32_t magic
Definition: nat_stun.h:44
#define GNUNET_YES
Definition: gnunet_common.h:77
uint32_t id[3]
Definition: nat_stun.h:37
static void generate_request_id(struct stun_header *req)
Fill the stun_header with a random request_id.
Definition: nat_api_stun.c:116
#define GNUNET_free(ptr)
Wrapper around free.
struct GNUNET_RESOLVER_RequestHandle * dns_active
Handle to a pending DNS lookup request.
Definition: nat_api_stun.c:60