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 static char const RCSID[] =
25 "$Id: plugin.c,v 1.12 2004/11/04 10:07:37 paulus Exp $";
26
27 #define _GNU_SOURCE 1
28 #include "pppoe.h"
29
30 #include "pppd/pppd.h"
31 #include "pppd/fsm.h"
32 #include "pppd/lcp.h"
33 #include "pppd/ipcp.h"
34 #include "pppd/ccp.h"
35 #include "pppd/pathnames.h"
36
37 #include <linux/types.h>
38 #include <syslog.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 "ppp_defs.h"
52 #include "if_ppp.h"
53 #include "if_pppox.h"
54
55 #define _PATH_ETHOPT _ROOT_PATH "/etc/ppp/options."
56
57 char pppd_version[] = VERSION;
58
59 /* From sys-linux.c in pppd -- MUST FIX THIS! */
60 extern int new_style_driver;
61
62 char *pppd_pppoe_service = NULL;
63 static char *acName = NULL;
64 static char *existingSession = NULL;
65 static int printACNames = 0;
66
67 static int PPPoEDevnameHook(char *cmd, char **argv, int doit);
68 static option_t Options[] = {
69 { "device name", o_wild, (void *) &PPPoEDevnameHook,
70 "PPPoE device name",
71 OPT_DEVNAM | OPT_PRIVFIX | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC,
72 devnam},
73 { "rp_pppoe_service", o_string, &pppd_pppoe_service,
74 "Desired PPPoE service name" },
75 { "rp_pppoe_ac", o_string, &acName,
76 "Desired PPPoE access concentrator name" },
77 { "rp_pppoe_sess", o_string, &existingSession,
78 "Attach to existing session (sessid:macaddr)" },
79 { "rp_pppoe_verbose", o_int, &printACNames,
80 "Be verbose about discovered access concentrators"},
81 { NULL }
82 };
83
84 static PPPoEConnection *conn = NULL;
85
86 /**********************************************************************
87 * %FUNCTION: PPPOEInitDevice
88 * %ARGUMENTS:
89 * None
90 * %RETURNS:
91 *
92 * %DESCRIPTION:
93 * Initializes PPPoE device.
94 ***********************************************************************/
95 static int
PPPOEInitDevice(void)96 PPPOEInitDevice(void)
97 {
98 conn = malloc(sizeof(PPPoEConnection));
99 if (!conn) {
100 fatal("Could not allocate memory for PPPoE session");
101 }
102 memset(conn, 0, sizeof(PPPoEConnection));
103 if (acName) {
104 SET_STRING(conn->acName, acName);
105 }
106 if (pppd_pppoe_service) {
107 SET_STRING(conn->serviceName, pppd_pppoe_service);
108 }
109 SET_STRING(conn->ifName, devnam);
110 conn->discoverySocket = -1;
111 conn->sessionSocket = -1;
112 conn->useHostUniq = 1;
113 conn->printACNames = printACNames;
114 return 1;
115 }
116
117 /**********************************************************************
118 * %FUNCTION: PPPOEConnectDevice
119 * %ARGUMENTS:
120 * None
121 * %RETURNS:
122 * Non-negative if all goes well; -1 otherwise
123 * %DESCRIPTION:
124 * Connects PPPoE device.
125 ***********************************************************************/
126 static int
PPPOEConnectDevice(void)127 PPPOEConnectDevice(void)
128 {
129 struct sockaddr_pppox sp;
130
131 strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam));
132 if (existingSession) {
133 unsigned int mac[ETH_ALEN];
134 int i, ses;
135 if (sscanf(existingSession, "%d:%x:%x:%x:%x:%x:%x",
136 &ses, &mac[0], &mac[1], &mac[2],
137 &mac[3], &mac[4], &mac[5]) != 7) {
138 fatal("Illegal value for rp_pppoe_sess option");
139 }
140 conn->session = htons(ses);
141 for (i=0; i<ETH_ALEN; i++) {
142 conn->peerEth[i] = (unsigned char) mac[i];
143 }
144 } else {
145 discovery(conn);
146 if (conn->discoveryState != STATE_SESSION) {
147 error("Unable to complete PPPoE Discovery");
148 return -1;
149 }
150 }
151
152 /* Set PPPoE session-number for further consumption */
153 ppp_session_number = ntohs(conn->session);
154
155 /* Make the session socket */
156 conn->sessionSocket = socket(AF_PPPOX, SOCK_STREAM, PX_PROTO_OE);
157 if (conn->sessionSocket < 0) {
158 fatal("Failed to create PPPoE socket: %m");
159 }
160 sp.sa_family = AF_PPPOX;
161 sp.sa_protocol = PX_PROTO_OE;
162 sp.sa_addr.pppoe.sid = conn->session;
163 memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
164 memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
165
166 /* Set remote_number for ServPoET */
167 sprintf(remote_number, "%02X:%02X:%02X:%02X:%02X:%02X",
168 (unsigned) conn->peerEth[0],
169 (unsigned) conn->peerEth[1],
170 (unsigned) conn->peerEth[2],
171 (unsigned) conn->peerEth[3],
172 (unsigned) conn->peerEth[4],
173 (unsigned) conn->peerEth[5]);
174
175 if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
176 sizeof(struct sockaddr_pppox)) < 0) {
177 fatal("Failed to connect PPPoE socket: %d %m", errno);
178 return -1;
179 }
180
181 return conn->sessionSocket;
182 }
183
184 static void
PPPOESendConfig(int mtu,u_int32_t asyncmap,int pcomp,int accomp)185 PPPOESendConfig(int mtu,
186 u_int32_t asyncmap,
187 int pcomp,
188 int accomp)
189 {
190 int sock;
191 struct ifreq ifr;
192
193 if (mtu > MAX_PPPOE_MTU) {
194 warn("Couldn't increase MTU to %d", mtu);
195 mtu = MAX_PPPOE_MTU;
196 }
197 sock = socket(AF_INET, SOCK_DGRAM, 0);
198 if (sock < 0) {
199 error("Couldn't create IP socket: %m");
200 return;
201 }
202 strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
203 ifr.ifr_mtu = mtu;
204 if (ioctl(sock, SIOCSIFMTU, &ifr) < 0) {
205 error("Couldn't set interface MTU to %d: %m", mtu);
206 return;
207 }
208 (void) close (sock);
209 }
210
211
212 static void
PPPOERecvConfig(int mru,u_int32_t asyncmap,int pcomp,int accomp)213 PPPOERecvConfig(int mru,
214 u_int32_t asyncmap,
215 int pcomp,
216 int accomp)
217 {
218 if (mru > MAX_PPPOE_MTU)
219 warn("Couldn't increase MRU to %d", mru);
220 }
221
222 /**********************************************************************
223 * %FUNCTION: PPPOEDisconnectDevice
224 * %ARGUMENTS:
225 * None
226 * %RETURNS:
227 * Nothing
228 * %DESCRIPTION:
229 * Disconnects PPPoE device
230 ***********************************************************************/
231 static void
PPPOEDisconnectDevice(void)232 PPPOEDisconnectDevice(void)
233 {
234 struct sockaddr_pppox sp;
235
236 sp.sa_family = AF_PPPOX;
237 sp.sa_protocol = PX_PROTO_OE;
238 sp.sa_addr.pppoe.sid = 0;
239 memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
240 memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
241 if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
242 sizeof(struct sockaddr_pppox)) < 0) {
243 fatal("Failed to disconnect PPPoE socket: %d %m", errno);
244 return;
245 }
246 close(conn->sessionSocket);
247 /* don't send PADT?? */
248 close(conn->discoverySocket);
249 }
250
251 static void
PPPOEDeviceOptions(void)252 PPPOEDeviceOptions(void)
253 {
254 char buf[256];
255 snprintf(buf, 256, _PATH_ETHOPT "%s",devnam);
256 if(!options_from_file(buf, 0, 0, 1))
257 exit(EXIT_OPTION_ERROR);
258
259 }
260
261 struct channel pppoe_channel;
262
263 /**********************************************************************
264 * %FUNCTION: PPPoEDevnameHook
265 * %ARGUMENTS:
266 * cmd -- the command (actually, the device name
267 * argv -- argument vector
268 * doit -- if non-zero, set device name. Otherwise, just check if possible
269 * %RETURNS:
270 * 1 if we will handle this device; 0 otherwise.
271 * %DESCRIPTION:
272 * Checks if name is a valid interface name; if so, returns 1. Also
273 * sets up devnam (string representation of device).
274 ***********************************************************************/
275 static int
PPPoEDevnameHook(char * cmd,char ** argv,int doit)276 PPPoEDevnameHook(char *cmd, char **argv, int doit)
277 {
278 int r = 1;
279 int fd;
280 struct ifreq ifr;
281
282 /* Only do it if name is "ethXXX", "nasXXX", "tapXXX" or "nic-XXXX.
283 In latter case strip off the "nic-" */
284 /* Thanks to Russ Couturier for this fix */
285 if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
286 /* Strip off "nic-" */
287 cmd += 4;
288 } else if (strlen(cmd) < 4
289 || (strncmp(cmd, "eth", 3) && strncmp(cmd, "nas", 3)
290 && strncmp(cmd, "tap", 3) && strncmp(cmd, "br", 2))) {
291 return 0;
292 }
293
294 /* Open a socket */
295 if ((fd = socket(PF_PACKET, SOCK_RAW, 0)) < 0) {
296 r = 0;
297 }
298
299 /* Try getting interface index */
300 if (r) {
301 strncpy(ifr.ifr_name, cmd, sizeof(ifr.ifr_name));
302 if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
303 r = 0;
304 } else {
305 if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
306 r = 0;
307 } else {
308 if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
309 error("Interface %s not Ethernet", cmd);
310 r=0;
311 }
312 }
313 }
314 }
315
316 /* Close socket */
317 close(fd);
318 if (r) {
319 strncpy(devnam, cmd, sizeof(devnam));
320 if (the_channel != &pppoe_channel) {
321
322 the_channel = &pppoe_channel;
323 modem = 0;
324
325 lcp_allowoptions[0].neg_accompression = 0;
326 lcp_wantoptions[0].neg_accompression = 0;
327
328 lcp_allowoptions[0].neg_asyncmap = 0;
329 lcp_wantoptions[0].neg_asyncmap = 0;
330
331 lcp_allowoptions[0].neg_pcompression = 0;
332 lcp_wantoptions[0].neg_pcompression = 0;
333
334 ccp_allowoptions[0].deflate = 0 ;
335 ccp_wantoptions[0].deflate = 0 ;
336
337 ipcp_allowoptions[0].neg_vj=0;
338 ipcp_wantoptions[0].neg_vj=0;
339
340 ccp_allowoptions[0].bsd_compress = 0;
341 ccp_wantoptions[0].bsd_compress = 0;
342
343 PPPOEInitDevice();
344 }
345 return 1;
346 }
347
348 return r;
349 }
350
351 /**********************************************************************
352 * %FUNCTION: plugin_init
353 * %ARGUMENTS:
354 * None
355 * %RETURNS:
356 * Nothing
357 * %DESCRIPTION:
358 * Initializes hooks for pppd plugin
359 ***********************************************************************/
360 void
plugin_init(void)361 plugin_init(void)
362 {
363 if (!ppp_available() && !new_style_driver) {
364 fatal("Linux kernel does not support PPPoE -- are you running 2.4.x?");
365 }
366
367 add_options(Options);
368
369 info("RP-PPPoE plugin version %s compiled against pppd %s",
370 RP_VERSION, VERSION);
371 }
372
373 /**********************************************************************
374 *%FUNCTION: fatalSys
375 *%ARGUMENTS:
376 * str -- error message
377 *%RETURNS:
378 * Nothing
379 *%DESCRIPTION:
380 * Prints a message plus the errno value to stderr and syslog and exits.
381 ***********************************************************************/
382 void
fatalSys(char const * str)383 fatalSys(char const *str)
384 {
385 char buf[1024];
386 int i = errno;
387 sprintf(buf, "%.256s: %.256s", str, strerror(i));
388 printErr(buf);
389 sprintf(buf, "RP-PPPoE: %.256s: %.256s", str, strerror(i));
390 sendPADT(conn, buf);
391 exit(1);
392 }
393
394 /**********************************************************************
395 *%FUNCTION: rp_fatal
396 *%ARGUMENTS:
397 * str -- error message
398 *%RETURNS:
399 * Nothing
400 *%DESCRIPTION:
401 * Prints a message to stderr and syslog and exits.
402 ***********************************************************************/
403 void
rp_fatal(char const * str)404 rp_fatal(char const *str)
405 {
406 char buf[1024];
407 printErr(str);
408 sprintf(buf, "RP-PPPoE: %.256s", str);
409 sendPADT(conn, buf);
410 exit(1);
411 }
412 /**********************************************************************
413 *%FUNCTION: sysErr
414 *%ARGUMENTS:
415 * str -- error message
416 *%RETURNS:
417 * Nothing
418 *%DESCRIPTION:
419 * Prints a message plus the errno value to syslog.
420 ***********************************************************************/
421 void
sysErr(char const * str)422 sysErr(char const *str)
423 {
424 rp_fatal(str);
425 }
426
427
428 struct channel pppoe_channel = {
429 options: Options,
430 process_extra_options: &PPPOEDeviceOptions,
431 check_options: NULL,
432 connect: &PPPOEConnectDevice,
433 disconnect: &PPPOEDisconnectDevice,
434 establish_ppp: &generic_establish_ppp,
435 disestablish_ppp: &generic_disestablish_ppp,
436 send_config: &PPPOESendConfig,
437 recv_config: &PPPOERecvConfig,
438 close: NULL,
439 cleanup: NULL
440 };
441