5 * Communication with the peer
7 * (c) 2001 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Trivial IP Encryption (TrIPE).
14 * TrIPE is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * TrIPE is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with TrIPE; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Header files ------------------------------------------------------*/
33 /*----- Static variables --------------------------------------------------*/
35 static peer
*peers
= 0;
38 /*----- Main code ---------------------------------------------------------*/
42 * Arguments: @int fd@ = file descriptor to read from
43 * @unsigned mode@ = what happened
44 * @void *v@ = an uninteresting pointer
48 * Use: Reads a packet from somewhere.
51 static void p_read(int fd
, unsigned mode
, void *v
)
60 /* --- Read the data --- */
64 n
= recvfrom(fd
, buf_i
, sizeof(buf_i
), 0, &a
.sa
, &sz
);
66 a_warn("PEER - socket-read-error -- %s", strerror(errno
));
70 /* --- Find the appropriate peer --- */
72 assert(a
.sa
.sa_family
== AF_INET
);
73 for (p
= peers
; p
; p
= p
->next
) {
74 if (p
->peer
.sin
.sin_addr
.s_addr
== a
.sin
.sin_addr
.s_addr
&&
75 p
->peer
.sin
.sin_port
== a
.sin
.sin_port
)
78 a_warn("PEER - unexpected-source INET %s %u",
79 inet_ntoa(a
.sin
.sin_addr
), (unsigned)ntohs(a
.sin
.sin_port
));
84 trace(T_PEER
, "peer: packet received from `%s'", p
->name
);
85 trace_block(T_PACKET
, "peer: packet contents", buf_i
, n
);
88 /* --- Pick the packet apart --- */
90 p
->st
.t_last
= time(0);
93 buf_init(&b
, buf_i
, n
);
94 if ((ch
= buf_getbyte(&b
)) < 0) {
95 a_warn("PEER %s bad-packet no-type", p
->name
);
98 switch (ch
& MSG_CATMASK
) {
100 if (ch
& MSG_TYPEMASK
) {
101 a_warn("PEER %s bad-packet unknown-type 0x%02x", p
->name
, ch
);
105 buf_init(&bb
, buf_o
, sizeof(buf_o
));
106 if (ksl_decrypt(&p
->ks
, MSG_PACKET
, &b
, &bb
)) {
108 a_warn("PEER %s decrypt-failed", p
->name
);
113 p
->st
.sz_ipin
+= BSZ(&b
);
114 tun_inject(&p
->t
, &bb
);
117 a_warn("PEER %s packet-build-failed", p
->name
);
121 kx_message(&p
->kx
, ch
& MSG_TYPEMASK
, &b
);
125 a_warn("PEER %s bad-packet unknown-category 0x%02x", p
->name
, ch
);
130 /* --- @p_txstart@ --- *
132 * Arguments: @peer *p@ = pointer to peer block
133 * @unsigned msg@ = message type code
135 * Returns: A pointer to a buffer to write to.
137 * Use: Starts sending to a peer. Only one send can happen at a
141 buf
*p_txstart(peer
*p
, unsigned msg
)
143 buf_init(&p
->b
, buf_o
, sizeof(buf_o
));
144 buf_putbyte(&p
->b
, msg
);
148 /* --- @p_txend@ --- *
150 * Arguments: @peer *p@ = pointer to peer block
154 * Use: Sends a packet to the peer.
157 void p_txend(peer
*p
)
160 a_warn("PEER %s packet-build-failed", p
->name
);
163 IF_TRACING(T_PEER
, trace_block(T_PACKET
, "peer: sending packet",
164 BBASE(&p
->b
), BLEN(&p
->b
)); )
165 if (sendto(sock
.fd
, BBASE(&p
->b
), BLEN(&p
->b
),
166 0, &p
->peer
.sa
, p
->sasz
) < 0)
167 a_warn("PEER %s socket-write-error -- %s", p
->name
, strerror(errno
));
170 p
->st
.sz_out
+= BLEN(&p
->b
);
176 * Arguments: @peer *p@ = pointer to peer block
177 * @buf *b@ = buffer containing incoming packet
181 * Use: Handles a packet which needs to be sent to a peer.
184 void p_tun(peer
*p
, buf
*b
)
186 buf
*bb
= p_txstart(p
, MSG_PACKET
);
189 if (ksl_encrypt(&p
->ks
, MSG_PACKET
, b
, bb
))
191 if (BOK(bb
) && BLEN(bb
)) {
193 p
->st
.sz_ipout
+= BLEN(bb
);
198 /* --- @p_interval@ --- *
204 * Use: Called periodically to do tidying.
207 void p_interval(void)
212 reload
= km_interval();
213 for (p
= peers
; p
; p
= pp
) {
221 /* --- @p_stats@ --- *
223 * Arguments: @peer *p@ = pointer to a peer block
225 * Returns: A pointer to the peer's statistics.
228 stats
*p_stats(peer
*p
) { return (&p
->st
); }
230 /* --- @p_ifname@ --- *
232 * Arguments: @peer *p@ = pointer to a peer block
234 * Returns: A pointer to the peer's interface name.
237 const char *p_ifname(peer
*p
) { return (tun_ifname(&p
->t
)); }
239 /* --- @p_addr@ --- *
241 * Arguments: @peer *p@ = pointer to a peer block
243 * Returns: A pointer to the peer's address.
246 const addr
*p_addr(peer
*p
) { return (&p
->peer
); }
248 /* --- @p_init@ --- *
250 * Arguments: @struct in_addr addr@ = address to bind to
251 * @unsigned port@ = port number to listen to
255 * Use: Initializes the peer system; creates the socket.
258 void p_init(struct in_addr addr
, unsigned port
)
261 struct sockaddr_in sin
;
264 /* --- Note on socket buffer sizes --- *
266 * For some bizarre reason, Linux 2.2 (at least) doubles the socket buffer
267 * sizes I pass to @setsockopt@. I'm not putting special-case code here
268 * for Linux: BSD (at least TCPv2) does what I tell it rather than second-
272 if ((fd
= socket(PF_INET
, SOCK_DGRAM
, 0)) < 0)
273 die(EXIT_FAILURE
, "socket creation failed: %s", strerror(errno
));
275 sin
.sin_family
= AF_INET
;
277 sin
.sin_port
= htons(port
);
278 if (bind(fd
, (struct sockaddr
*)&sin
, sizeof(sin
)))
279 die(EXIT_FAILURE
, "bind failed: %s", strerror(errno
));
280 if (setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &len
, sizeof(len
)) ||
281 setsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
, &len
, sizeof(len
))) {
282 die(EXIT_FAILURE
, "failed to set socket buffer sizes: %s",
285 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
286 sel_initfile(&sel
, &sock
, fd
, SEL_READ
, p_read
, 0);
288 T( trace(T_PEER
, "peer: created socket"); )
291 /* --- @p_port@ --- *
295 * Returns: Port number used for socket.
298 unsigned p_port(void)
301 size_t sz
= sizeof(addr
);
303 if (getsockname(sock
.fd
, &a
.sa
, &sz
))
304 die(EXIT_FAILURE
, "couldn't read port number: %s", strerror(errno
));
305 assert(a
.sa
.sa_family
== AF_INET
);
306 return (ntohs(a
.sin
.sin_port
));
309 /* --- @p_create@ --- *
311 * Arguments: @const char *name@ = name for this peer
312 * @struct sockaddr *sa@ = socket address of peer
313 * @size_t sz@ = size of socket address
315 * Returns: Pointer to the peer block, or null if it failed.
317 * Use: Creates a new named peer block. No peer is actually attached
321 peer
*p_create(const char *name
, struct sockaddr
*sa
, size_t sz
)
323 peer
*p
= CREATE(peer
);
324 T( trace(T_PEER
, "peer: creating new peer `%s'", name
); )
325 p
->name
= xstrdup(name
);
328 memcpy(&p
->peer
.sa
, sa
, sz
);
330 memset(&p
->st
, 0, sizeof(stats
));
331 p
->st
.t_start
= time(0);
332 if (kx_init(&p
->kx
, p
, &p
->ks
))
334 if (tun_create(&p
->t
, p
))
340 switch (p
->peer
.sa
.sa_family
) {
342 a_notify("ADD %s INET %s %u",
344 inet_ntoa(p
->peer
.sin
.sin_addr
),
345 (unsigned)ntohs(p
->peer
.sin
.sin_port
));
348 a_notify("ADD %s UNKNOWN", name
);
351 a_notify("KXSTART %s", name
); /* Couldn't tell anyone before */
362 /* --- @p_name@ --- *
364 * Arguments: @peer *p@ = pointer to a peer block
366 * Returns: A pointer to the peer's name.
369 const char *p_name(peer
*p
) { return (p
->name
); }
371 /* --- @p_find@ --- *
373 * Arguments: @const char *name@ = name to look up
375 * Returns: Pointer to the peer block, or null if not found.
377 * Use: Finds a peer by name.
380 peer
*p_find(const char *name
)
383 for (p
= peers
; p
; p
= p
->next
) {
384 if (strcmp(name
, p
->name
) == 0)
390 /* --- @p_destroy@ --- *
392 * Arguments: @peer *p@ = pointer to a peer
396 * Use: Destroys a peer.
399 void p_destroy(peer
*p
)
401 T( trace(T_PEER
, "peer: destroying peer `%s'", p
->name
); )
402 a_notify("KILL %s", p
->name
);
408 p
->next
->prev
= p
->prev
;
410 p
->prev
->next
= p
->next
;
416 /* --- @p_first@, @p_next@ --- *
418 * Arguments: @peer *p@ = a peer block
420 * Returns: @peer_first@ returns the first peer in some ordering;
421 * @peer_next@ returns the peer following a given one in the
422 * same ordering. Null is returned for the end of the list.
425 peer
*p_first(void) { return (peers
); }
426 peer
*p_next(peer
*p
) { return (p
->next
); }
428 /*----- That's all, folks -------------------------------------------------*/