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
24static 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
57char pppd_version[] = VERSION;
58
59/* From sys-linux.c in pppd -- MUST FIX THIS! */
60extern int new_style_driver;
61
62char *pppd_pppoe_service = NULL;
63static char *acName = NULL;
64static char *existingSession = NULL;
65static int printACNames = 0;
66
67static int PPPoEDevnameHook(char *cmd, char **argv, int doit);
68static 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
84static PPPoEConnection *conn = NULL;
85
86/**********************************************************************
87 * %FUNCTION: PPPOEInitDevice
88 * %ARGUMENTS:
89 * None
90 * %RETURNS:
91 *
92 * %DESCRIPTION:
93 * Initializes PPPoE device.
94 ***********************************************************************/
95static int
96PPPOEInitDevice(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 ***********************************************************************/
126static int
127PPPOEConnectDevice(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
184static void
185PPPOESendConfig(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
212static void
213PPPOERecvConfig(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 ***********************************************************************/
231static void
232PPPOEDisconnectDevice(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
251static void
252PPPOEDeviceOptions(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
261struct 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 ***********************************************************************/
275static int
276PPPoEDevnameHook(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 ***********************************************************************/
360void
361plugin_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***********************************************************************/
382void
383fatalSys(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***********************************************************************/
403void
404rp_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***********************************************************************/
421void
422sysErr(char const *str)
423{
424    rp_fatal(str);
425}
426
427
428struct 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