1 /***********************************************************************
2 *
3 * plugin.c
4 *
5 * pppd plugin for kernel-mode PPPoE on Linux
6 *
7 * Copyright (C) 2001 by Roaring Penguin Software Inc., Michal Ostrowski
8 * and Jamal Hadi Salim.
9 *
10 * Much code and many ideas derived from pppoe plugin by Michal
11 * Ostrowski and Jamal Hadi Salim, which carries this copyright:
12 *
13 * Copyright 2000 Michal Ostrowski <mostrows@styx.uwaterloo.ca>,
14 * Jamal Hadi Salim <hadi@cyberus.ca>
15 * Borrows heavily from the PPPoATM plugin by Mitchell Blank Jr.,
16 * which is based in part on work from Jens Axboe and Paul Mackerras.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 *
23 ***********************************************************************/
24
25 static char const RCSID[] =
26 "$Id: plugin.c,v 1.17 2008/06/15 04:35:50 paulus Exp $";
27
28 #define _GNU_SOURCE 1
29 #include "pppoe.h"
30
31 #include "pppd/pppd.h"
32 #include "pppd/fsm.h"
33 #include "pppd/lcp.h"
34 #include "pppd/ipcp.h"
35 #include "pppd/ccp.h"
36 /* #include "pppd/pathnames.h" */
37
38 #include <linux/types.h>
39 #include <sys/ioctl.h>
40 #include <sys/types.h>
41 #include <sys/socket.h>
42 #include <sys/stat.h>
43 #include <string.h>
44 #include <stdlib.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <fcntl.h>
48 #include <signal.h>
49 #include <net/ethernet.h>
50 #include <net/if_arp.h>
51 #include <linux/ppp_defs.h>
52 #include <linux/if_pppox.h>
53
54 #ifndef _ROOT_PATH
55 #define _ROOT_PATH ""
56 #endif
57
58 #define _PATH_ETHOPT _ROOT_PATH "/etc/ppp/options."
59
60 char pppd_version[] = VERSION;
61
62 /* From sys-linux.c in pppd -- MUST FIX THIS! */
63 extern int new_style_driver;
64
65 char *pppd_pppoe_service = NULL;
66 static char *acName = NULL;
67 static char *existingSession = NULL;
68 static int printACNames = 0;
69 static char *pppoe_reqd_mac = NULL;
70 unsigned char pppoe_reqd_mac_addr[6];
71
72 static int PPPoEDevnameHook(char *cmd, char **argv, int doit);
73 static option_t Options[] = {
74 { "device name", o_wild, (void *) &PPPoEDevnameHook,
75 "PPPoE device name",
76 OPT_DEVNAM | OPT_PRIVFIX | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC,
77 devnam},
78 { "rp_pppoe_service", o_string, &pppd_pppoe_service,
79 "Desired PPPoE service name" },
80 { "rp_pppoe_ac", o_string, &acName,
81 "Desired PPPoE access concentrator name" },
82 { "rp_pppoe_sess", o_string, &existingSession,
83 "Attach to existing session (sessid:macaddr)" },
84 { "rp_pppoe_verbose", o_int, &printACNames,
85 "Be verbose about discovered access concentrators"},
86 { "pppoe-mac", o_string, &pppoe_reqd_mac,
87 "Only connect to specified MAC address" },
88 { NULL }
89 };
90 int (*OldDevnameHook)(char *cmd, char **argv, int doit) = NULL;
91 static PPPoEConnection *conn = NULL;
92
93 /**********************************************************************
94 * %FUNCTION: PPPOEInitDevice
95 * %ARGUMENTS:
96 * None
97 * %RETURNS:
98 *
99 * %DESCRIPTION:
100 * Initializes PPPoE device.
101 ***********************************************************************/
102 static int
PPPOEInitDevice(void)103 PPPOEInitDevice(void)
104 {
105 conn = malloc(sizeof(PPPoEConnection));
106 if (!conn) {
107 novm("PPPoE session data");
108 }
109 memset(conn, 0, sizeof(PPPoEConnection));
110 conn->ifName = devnam;
111 conn->discoverySocket = -1;
112 conn->sessionSocket = -1;
113 conn->useHostUniq = 1;
114 conn->printACNames = printACNames;
115 conn->discoveryTimeout = PADI_TIMEOUT;
116 return 1;
117 }
118
119 /**********************************************************************
120 * %FUNCTION: PPPOEConnectDevice
121 * %ARGUMENTS:
122 * None
123 * %RETURNS:
124 * Non-negative if all goes well; -1 otherwise
125 * %DESCRIPTION:
126 * Connects PPPoE device.
127 ***********************************************************************/
128 static int
PPPOEConnectDevice(void)129 PPPOEConnectDevice(void)
130 {
131 struct sockaddr_pppox sp;
132 struct ifreq ifr;
133 int s;
134
135 /* Open session socket before discovery phase, to avoid losing session */
136 /* packets sent by peer just after PADS packet (noted on some Cisco */
137 /* server equipment). */
138 /* Opening this socket just before waitForPADS in the discovery() */
139 /* function would be more appropriate, but it would mess-up the code */
140 conn->sessionSocket = socket(AF_PPPOX, SOCK_STREAM, PX_PROTO_OE);
141 if (conn->sessionSocket < 0) {
142 error("Failed to create PPPoE socket: %m");
143 return -1;
144 }
145
146 /* Restore configuration */
147 lcp_allowoptions[0].mru = conn->mtu;
148 lcp_wantoptions[0].mru = conn->mru;
149
150 /* Update maximum MRU */
151 s = socket(AF_INET, SOCK_DGRAM, 0);
152 if (s < 0) {
153 error("Can't get MTU for %s: %m", conn->ifName);
154 goto errout;
155 }
156 strncpy(ifr.ifr_name, conn->ifName, sizeof(ifr.ifr_name));
157 if (ioctl(s, SIOCGIFMTU, &ifr) < 0) {
158 error("Can't get MTU for %s: %m", conn->ifName);
159 close(s);
160 goto errout;
161 }
162 close(s);
163
164 if (lcp_allowoptions[0].mru > ifr.ifr_mtu - TOTAL_OVERHEAD)
165 lcp_allowoptions[0].mru = ifr.ifr_mtu - TOTAL_OVERHEAD;
166 if (lcp_wantoptions[0].mru > ifr.ifr_mtu - TOTAL_OVERHEAD)
167 lcp_wantoptions[0].mru = ifr.ifr_mtu - TOTAL_OVERHEAD;
168
169 conn->acName = acName;
170 conn->serviceName = pppd_pppoe_service;
171 strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam));
172 if (existingSession) {
173 unsigned int mac[ETH_ALEN];
174 int i, ses;
175 if (sscanf(existingSession, "%d:%x:%x:%x:%x:%x:%x",
176 &ses, &mac[0], &mac[1], &mac[2],
177 &mac[3], &mac[4], &mac[5]) != 7) {
178 fatal("Illegal value for rp_pppoe_sess option");
179 }
180 conn->session = htons(ses);
181 for (i=0; i<ETH_ALEN; i++) {
182 conn->peerEth[i] = (unsigned char) mac[i];
183 }
184 } else {
185 conn->discoverySocket =
186 openInterface(conn->ifName, Eth_PPPOE_Discovery, conn->myEth);
187 discovery(conn);
188 if (conn->discoveryState != STATE_SESSION) {
189 error("Unable to complete PPPoE Discovery");
190 goto errout;
191 }
192 }
193
194 /* Set PPPoE session-number for further consumption */
195 ppp_session_number = ntohs(conn->session);
196
197 sp.sa_family = AF_PPPOX;
198 sp.sa_protocol = PX_PROTO_OE;
199 sp.sa_addr.pppoe.sid = conn->session;
200 memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
201 memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
202
203 /* Set remote_number for ServPoET */
204 sprintf(remote_number, "%02X:%02X:%02X:%02X:%02X:%02X",
205 (unsigned) conn->peerEth[0],
206 (unsigned) conn->peerEth[1],
207 (unsigned) conn->peerEth[2],
208 (unsigned) conn->peerEth[3],
209 (unsigned) conn->peerEth[4],
210 (unsigned) conn->peerEth[5]);
211
212 warn("Connected to %02X:%02X:%02X:%02X:%02X:%02X via interface %s",
213 (unsigned) conn->peerEth[0],
214 (unsigned) conn->peerEth[1],
215 (unsigned) conn->peerEth[2],
216 (unsigned) conn->peerEth[3],
217 (unsigned) conn->peerEth[4],
218 (unsigned) conn->peerEth[5],
219 conn->ifName);
220
221 script_setenv("MACREMOTE", remote_number, 0);
222
223 if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
224 sizeof(struct sockaddr_pppox)) < 0) {
225 error("Failed to connect PPPoE socket: %d %m", errno);
226 goto errout;
227 }
228
229 return conn->sessionSocket;
230
231 errout:
232 if (conn->discoverySocket >= 0) {
233 sendPADT(conn, NULL);
234 close(conn->discoverySocket);
235 conn->discoverySocket = -1;
236 }
237 close(conn->sessionSocket);
238 return -1;
239 }
240
241 static void
PPPOERecvConfig(int mru,u_int32_t asyncmap,int pcomp,int accomp)242 PPPOERecvConfig(int mru,
243 u_int32_t asyncmap,
244 int pcomp,
245 int accomp)
246 {
247 #if 0 /* broken protocol, but no point harrassing the users I guess... */
248 if (mru > MAX_PPPOE_MTU)
249 warn("Couldn't increase MRU to %d", mru);
250 #endif
251 }
252
253 /**********************************************************************
254 * %FUNCTION: PPPOEDisconnectDevice
255 * %ARGUMENTS:
256 * None
257 * %RETURNS:
258 * Nothing
259 * %DESCRIPTION:
260 * Disconnects PPPoE device
261 ***********************************************************************/
262 static void
PPPOEDisconnectDevice(void)263 PPPOEDisconnectDevice(void)
264 {
265 struct sockaddr_pppox sp;
266
267 sp.sa_family = AF_PPPOX;
268 sp.sa_protocol = PX_PROTO_OE;
269 sp.sa_addr.pppoe.sid = 0;
270 memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
271 memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
272 if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
273 sizeof(struct sockaddr_pppox)) < 0)
274 error("Failed to disconnect PPPoE socket: %d %m", errno);
275 close(conn->sessionSocket);
276 /* don't send PADT?? */
277 if (conn->discoverySocket >= 0)
278 close(conn->discoverySocket);
279 }
280
281 static void
PPPOEDeviceOptions(void)282 PPPOEDeviceOptions(void)
283 {
284 char buf[256];
285 snprintf(buf, 256, _PATH_ETHOPT "%s", devnam);
286 if (!options_from_file(buf, 0, 0, 1))
287 exit(EXIT_OPTION_ERROR);
288
289 }
290
291 struct channel pppoe_channel;
292
293 /**********************************************************************
294 * %FUNCTION: PPPoEDevnameHook
295 * %ARGUMENTS:
296 * cmd -- the command (actually, the device name
297 * argv -- argument vector
298 * doit -- if non-zero, set device name. Otherwise, just check if possible
299 * %RETURNS:
300 * 1 if we will handle this device; 0 otherwise.
301 * %DESCRIPTION:
302 * Checks if name is a valid interface name; if so, returns 1. Also
303 * sets up devnam (string representation of device).
304 ***********************************************************************/
305 static int
PPPoEDevnameHook(char * cmd,char ** argv,int doit)306 PPPoEDevnameHook(char *cmd, char **argv, int doit)
307 {
308 int r = 1;
309 int fd;
310 struct ifreq ifr;
311
312 /*
313 * Take any otherwise-unrecognized option as a possible device name,
314 * and test if it is the name of a network interface with a
315 * hardware address whose sa_family is ARPHRD_ETHER.
316 */
317 if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
318 /* Strip off "nic-" */
319 cmd += 4;
320 }
321
322 /* Open a socket */
323 if ((fd = socket(PF_PACKET, SOCK_RAW, 0)) < 0) {
324 r = 0;
325 }
326
327 /* Try getting interface index */
328 if (r) {
329 strncpy(ifr.ifr_name, cmd, sizeof(ifr.ifr_name));
330 if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
331 r = 0;
332 } else {
333 if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
334 r = 0;
335 } else {
336 if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
337 if (doit)
338 error("Interface %s not Ethernet", cmd);
339 r = 0;
340 }
341 }
342 }
343 }
344
345 /* Close socket */
346 close(fd);
347 if (r && doit) {
348 strncpy(devnam, cmd, sizeof(devnam));
349 if (the_channel != &pppoe_channel) {
350
351 the_channel = &pppoe_channel;
352 modem = 0;
353
354 PPPOEInitDevice();
355 }
356 return 1;
357 }
358
359 return r;
360 }
361
362 /**********************************************************************
363 * %FUNCTION: plugin_init
364 * %ARGUMENTS:
365 * None
366 * %RETURNS:
367 * Nothing
368 * %DESCRIPTION:
369 * Initializes hooks for pppd plugin
370 ***********************************************************************/
371 void
plugin_init(void)372 plugin_init(void)
373 {
374 if (!ppp_available() && !new_style_driver) {
375 fatal("Linux kernel does not support PPPoE -- are you running 2.4.x?");
376 }
377
378 add_options(Options);
379
380 info("RP-PPPoE plugin version %s compiled against pppd %s",
381 RP_VERSION, VERSION);
382 }
383
pppoe_check_options(void)384 void pppoe_check_options(void)
385 {
386 unsigned int mac[6];
387 int i;
388
389 if (pppoe_reqd_mac != NULL) {
390 if (sscanf(pppoe_reqd_mac, "%x:%x:%x:%x:%x:%x",
391 &mac[0], &mac[1], &mac[2], &mac[3],
392 &mac[4], &mac[5]) != 6) {
393 option_error("cannot parse pppoe-mac option value");
394 exit(EXIT_OPTION_ERROR);
395 }
396 for (i = 0; i < 6; ++i)
397 conn->req_peer_mac[i] = mac[i];
398 conn->req_peer = 1;
399 }
400
401 lcp_allowoptions[0].neg_accompression = 0;
402 lcp_wantoptions[0].neg_accompression = 0;
403
404 lcp_allowoptions[0].neg_asyncmap = 0;
405 lcp_wantoptions[0].neg_asyncmap = 0;
406
407 lcp_allowoptions[0].neg_pcompression = 0;
408 lcp_wantoptions[0].neg_pcompression = 0;
409
410 if (lcp_allowoptions[0].mru > MAX_PPPOE_MTU)
411 lcp_allowoptions[0].mru = MAX_PPPOE_MTU;
412 if (lcp_wantoptions[0].mru > MAX_PPPOE_MTU)
413 lcp_wantoptions[0].mru = MAX_PPPOE_MTU;
414
415 /* Save configuration */
416 conn->mtu = lcp_allowoptions[0].mru;
417 conn->mru = lcp_wantoptions[0].mru;
418
419 ccp_allowoptions[0].deflate = 0;
420 ccp_wantoptions[0].deflate = 0;
421
422 ipcp_allowoptions[0].neg_vj = 0;
423 ipcp_wantoptions[0].neg_vj = 0;
424
425 ccp_allowoptions[0].bsd_compress = 0;
426 ccp_wantoptions[0].bsd_compress = 0;
427 }
428
429 struct channel pppoe_channel = {
430 .options = Options,
431 .process_extra_options = &PPPOEDeviceOptions,
432 .check_options = pppoe_check_options,
433 .connect = &PPPOEConnectDevice,
434 .disconnect = &PPPOEDisconnectDevice,
435 .establish_ppp = &generic_establish_ppp,
436 .disestablish_ppp = &generic_disestablish_ppp,
437 .send_config = NULL,
438 .recv_config = &PPPOERecvConfig,
439 .close = NULL,
440 .cleanup = NULL
441 };
442