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
));
83 T( trace(T_PEER
, "peer: packet received from `%s'", p
->name
);
84 trace_block(T_PACKET
, "peer: packet contents", buf_i
, n
); )
86 /* --- Pick the packet apart --- */
88 p
->st
.t_last
= time(0);
91 buf_init(&b
, buf_i
, n
);
92 if ((ch
= buf_getbyte(&b
)) < 0) {
93 a_warn("PEER %s bad-packet no-type", p
->name
);
96 switch (ch
& MSG_CATMASK
) {
98 if (ch
& MSG_TYPEMASK
) {
99 a_warn("PEER %s bad-packet unknown-type 0x%02x", p
->name
, ch
);
103 buf_init(&bb
, buf_o
, sizeof(buf_o
));
104 if (ksl_decrypt(&p
->ks
, MSG_PACKET
, &b
, &bb
)) {
106 a_warn("PEER %s decrypt-failed", p
->name
);
111 p
->st
.sz_ipin
+= BSZ(&b
);
112 tun_inject(&p
->t
, &bb
);
115 a_warn("PEER %s packet-build-failed", p
->name
);
119 kx_message(&p
->kx
, ch
& MSG_TYPEMASK
, &b
);
123 a_warn("PEER %s bad-packet unknown-category 0x%02x", p
->name
, ch
);
128 /* --- @p_txstart@ --- *
130 * Arguments: @peer *p@ = pointer to peer block
131 * @unsigned msg@ = message type code
133 * Returns: A pointer to a buffer to write to.
135 * Use: Starts sending to a peer. Only one send can happen at a
139 buf
*p_txstart(peer
*p
, unsigned msg
)
141 buf_init(&p
->b
, buf_o
, sizeof(buf_o
));
142 buf_putbyte(&p
->b
, msg
);
146 /* --- @p_txend@ --- *
148 * Arguments: @peer *p@ = pointer to peer block
152 * Use: Sends a packet to the peer.
155 void p_txend(peer
*p
)
158 a_warn("PEER %s packet-build-failed", p
->name
);
161 IF_TRACING(T_PEER
, trace_block(T_PACKET
, "peer: sending packet",
162 BBASE(&p
->b
), BLEN(&p
->b
)); )
163 if (sendto(sock
.fd
, BBASE(&p
->b
), BLEN(&p
->b
),
164 0, &p
->peer
.sa
, p
->sasz
) < 0)
165 a_warn("PEER %s socket-write-error -- %s", p
->name
, strerror(errno
));
168 p
->st
.sz_out
+= BLEN(&p
->b
);
174 * Arguments: @peer *p@ = pointer to peer block
175 * @buf *b@ = buffer containing incoming packet
179 * Use: Handles a packet which needs to be sent to a peer.
182 void p_tun(peer
*p
, buf
*b
)
184 buf
*bb
= p_txstart(p
, MSG_PACKET
);
187 if (ksl_encrypt(&p
->ks
, MSG_PACKET
, b
, bb
))
189 if (BOK(bb
) && BLEN(bb
)) {
191 p
->st
.sz_ipout
+= BLEN(bb
);
196 /* --- @p_interval@ --- *
202 * Use: Called periodically to do tidying.
205 void p_interval(void)
210 reload
= km_interval();
211 for (p
= peers
; p
; p
= pp
) {
219 /* --- @p_stats@ --- *
221 * Arguments: @peer *p@ = pointer to a peer block
223 * Returns: A pointer to the peer's statistics.
226 stats
*p_stats(peer
*p
) { return (&p
->st
); }
228 /* --- @p_ifname@ --- *
230 * Arguments: @peer *p@ = pointer to a peer block
232 * Returns: A pointer to the peer's interface name.
235 const char *p_ifname(peer
*p
) { return (tun_ifname(&p
->t
)); }
237 /* --- @p_addr@ --- *
239 * Arguments: @peer *p@ = pointer to a peer block
241 * Returns: A pointer to the peer's address.
244 const addr
*p_addr(peer
*p
) { return (&p
->peer
); }
246 /* --- @p_init@ --- *
248 * Arguments: @struct in_addr addr@ = address to bind to
249 * @unsigned port@ = port number to listen to
253 * Use: Initializes the peer system; creates the socket.
256 void p_init(struct in_addr addr
, unsigned port
)
259 struct sockaddr_in sin
;
262 /* --- Note on socket buffer sizes --- *
264 * For some bizarre reason, Linux 2.2 (at least) doubles the socket buffer
265 * sizes I pass to @setsockopt@. I'm not putting special-case code here
266 * for Linux: BSD (at least TCPv2) does what I tell it rather than second-
270 if ((fd
= socket(PF_INET
, SOCK_DGRAM
, 0)) < 0)
271 die(EXIT_FAILURE
, "socket creation failed: %s", strerror(errno
));
273 sin
.sin_family
= AF_INET
;
275 sin
.sin_port
= htons(port
);
276 if (bind(fd
, (struct sockaddr
*)&sin
, sizeof(sin
)))
277 die(EXIT_FAILURE
, "bind failed: %s", strerror(errno
));
278 if (setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &len
, sizeof(len
)) ||
279 setsockopt(fd
, SOL_SOCKET
, SO_SNDBUF
, &len
, sizeof(len
))) {
280 die(EXIT_FAILURE
, "failed to set socket buffer sizes: %s",
283 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
284 sel_initfile(&sel
, &sock
, fd
, SEL_READ
, p_read
, 0);
286 T( trace(T_PEER
, "peer: created socket"); )
289 /* --- @p_port@ --- *
293 * Returns: Port number used for socket.
296 unsigned p_port(void)
299 size_t sz
= sizeof(addr
);
301 if (getsockname(sock
.fd
, &a
.sa
, &sz
))
302 die(EXIT_FAILURE
, "couldn't read port number: %s", strerror(errno
));
303 assert(a
.sa
.sa_family
== AF_INET
);
304 return (ntohs(a
.sin
.sin_port
));
307 /* --- @p_create@ --- *
309 * Arguments: @const char *name@ = name for this peer
310 * @struct sockaddr *sa@ = socket address of peer
311 * @size_t sz@ = size of socket address
313 * Returns: Pointer to the peer block, or null if it failed.
315 * Use: Creates a new named peer block. No peer is actually attached
319 peer
*p_create(const char *name
, struct sockaddr
*sa
, size_t sz
)
321 peer
*p
= CREATE(peer
);
322 T( trace(T_PEER
, "peer: creating new peer `%s'", name
); )
323 p
->name
= xstrdup(name
);
326 memcpy(&p
->peer
.sa
, sa
, sz
);
328 memset(&p
->st
, 0, sizeof(stats
));
329 p
->st
.t_start
= time(0);
330 if (kx_init(&p
->kx
, p
, &p
->ks
))
332 if (tun_create(&p
->t
, p
))
338 switch (p
->peer
.sa
.sa_family
) {
340 a_notify("ADD %s INET %s %u",
342 inet_ntoa(p
->peer
.sin
.sin_addr
),
343 (unsigned)ntohs(p
->peer
.sin
.sin_port
));
346 a_notify("ADD %s UNKNOWN", name
);
349 a_notify("KXSTART %s", name
); /* Couldn't tell anyone before */
360 /* --- @p_name@ --- *
362 * Arguments: @peer *p@ = pointer to a peer block
364 * Returns: A pointer to the peer's name.
367 const char *p_name(peer
*p
) { return (p
->name
); }
369 /* --- @p_find@ --- *
371 * Arguments: @const char *name@ = name to look up
373 * Returns: Pointer to the peer block, or null if not found.
375 * Use: Finds a peer by name.
378 peer
*p_find(const char *name
)
381 for (p
= peers
; p
; p
= p
->next
) {
382 if (strcmp(name
, p
->name
) == 0)
388 /* --- @p_destroy@ --- *
390 * Arguments: @peer *p@ = pointer to a peer
394 * Use: Destroys a peer.
397 void p_destroy(peer
*p
)
399 T( trace(T_PEER
, "peer: destroying peer `%s'", p
->name
); )
400 a_notify("KILL %s", p
->name
);
406 p
->next
->prev
= p
->prev
;
408 p
->prev
->next
= p
->next
;
414 /* --- @p_first@, @p_next@ --- *
416 * Arguments: @peer *p@ = a peer block
418 * Returns: @peer_first@ returns the first peer in some ordering;
419 * @peer_next@ returns the peer following a given one in the
420 * same ordering. Null is returned for the end of the list.
423 peer
*p_first(void) { return (peers
); }
424 peer
*p_next(peer
*p
) { return (p
->next
); }
426 /*----- That's all, folks -------------------------------------------------*/