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 1.15 2006/05/29 23:29:16 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
185PPPOERecvConfig(int mru,
186		u_int32_t asyncmap,
187		int pcomp,
188		int accomp)
189{
190#if 0 /* broken protocol, but no point harrassing the users I guess... */
191    if (mru > MAX_PPPOE_MTU)
192	warn("Couldn't increase MRU to %d", mru);
193#endif
194}
195
196/**********************************************************************
197 * %FUNCTION: PPPOEDisconnectDevice
198 * %ARGUMENTS:
199 * None
200 * %RETURNS:
201 * Nothing
202 * %DESCRIPTION:
203 * Disconnects PPPoE device
204 ***********************************************************************/
205static void
206PPPOEDisconnectDevice(void)
207{
208    struct sockaddr_pppox sp;
209
210    sp.sa_family = AF_PPPOX;
211    sp.sa_protocol = PX_PROTO_OE;
212    sp.sa_addr.pppoe.sid = 0;
213    memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
214    memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
215    if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
216		sizeof(struct sockaddr_pppox)) < 0) {
217	fatal("Failed to disconnect PPPoE socket: %d %m", errno);
218	return;
219    }
220    close(conn->sessionSocket);
221    /* don't send PADT?? */
222    close(conn->discoverySocket);
223}
224
225static void
226PPPOEDeviceOptions(void)
227{
228    char buf[256];
229    snprintf(buf, 256, _PATH_ETHOPT "%s",devnam);
230    if(!options_from_file(buf, 0, 0, 1))
231	exit(EXIT_OPTION_ERROR);
232
233}
234
235struct channel pppoe_channel;
236
237/**********************************************************************
238 * %FUNCTION: PPPoEDevnameHook
239 * %ARGUMENTS:
240 * cmd -- the command (actually, the device name
241 * argv -- argument vector
242 * doit -- if non-zero, set device name.  Otherwise, just check if possible
243 * %RETURNS:
244 * 1 if we will handle this device; 0 otherwise.
245 * %DESCRIPTION:
246 * Checks if name is a valid interface name; if so, returns 1.  Also
247 * sets up devnam (string representation of device).
248 ***********************************************************************/
249static int
250PPPoEDevnameHook(char *cmd, char **argv, int doit)
251{
252    int r = 1;
253    int fd;
254    struct ifreq ifr;
255
256    /*
257     * Take any otherwise-unrecognized option as a possible device name,
258     * and test if it is the name of a network interface with a
259     * hardware address whose sa_family is ARPHRD_ETHER.
260     */
261    if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
262	/* Strip off "nic-" */
263	cmd += 4;
264    }
265
266    /* Open a socket */
267    if ((fd = socket(PF_PACKET, SOCK_RAW, 0)) < 0) {
268	r = 0;
269    }
270
271    /* Try getting interface index */
272    if (r) {
273	strncpy(ifr.ifr_name, cmd, sizeof(ifr.ifr_name));
274	if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
275	    r = 0;
276	} else {
277	    if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
278		r = 0;
279	    } else {
280		if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
281		    if (doit)
282			error("Interface %s not Ethernet", cmd);
283		    r = 0;
284		}
285	    }
286	}
287    }
288
289    /* Close socket */
290    close(fd);
291    if (r && doit) {
292	strncpy(devnam, cmd, sizeof(devnam));
293	if (the_channel != &pppoe_channel) {
294
295	    the_channel = &pppoe_channel;
296	    modem = 0;
297
298	    PPPOEInitDevice();
299	}
300	return 1;
301    }
302
303    return r;
304}
305
306/**********************************************************************
307 * %FUNCTION: plugin_init
308 * %ARGUMENTS:
309 * None
310 * %RETURNS:
311 * Nothing
312 * %DESCRIPTION:
313 * Initializes hooks for pppd plugin
314 ***********************************************************************/
315void
316plugin_init(void)
317{
318    if (!ppp_available() && !new_style_driver) {
319	fatal("Linux kernel does not support PPPoE -- are you running 2.4.x?");
320    }
321
322    add_options(Options);
323
324    info("RP-PPPoE plugin version %s compiled against pppd %s",
325	 RP_VERSION, VERSION);
326}
327
328/**********************************************************************
329*%FUNCTION: fatalSys
330*%ARGUMENTS:
331* str -- error message
332*%RETURNS:
333* Nothing
334*%DESCRIPTION:
335* Prints a message plus the errno value to stderr and syslog and exits.
336***********************************************************************/
337void
338fatalSys(char const *str)
339{
340    char buf[1024];
341    int i = errno;
342    sprintf(buf, "%.256s: %.256s", str, strerror(i));
343    printErr(buf);
344    sprintf(buf, "RP-PPPoE: %.256s: %.256s", str, strerror(i));
345    sendPADT(conn, buf);
346    exit(1);
347}
348
349/**********************************************************************
350*%FUNCTION: rp_fatal
351*%ARGUMENTS:
352* str -- error message
353*%RETURNS:
354* Nothing
355*%DESCRIPTION:
356* Prints a message to stderr and syslog and exits.
357***********************************************************************/
358void
359rp_fatal(char const *str)
360{
361    char buf[1024];
362    printErr(str);
363    sprintf(buf, "RP-PPPoE: %.256s", str);
364    sendPADT(conn, buf);
365    exit(1);
366}
367/**********************************************************************
368*%FUNCTION: sysErr
369*%ARGUMENTS:
370* str -- error message
371*%RETURNS:
372* Nothing
373*%DESCRIPTION:
374* Prints a message plus the errno value to syslog.
375***********************************************************************/
376void
377sysErr(char const *str)
378{
379    rp_fatal(str);
380}
381
382void pppoe_check_options(void)
383{
384    lcp_allowoptions[0].neg_accompression = 0;
385    lcp_wantoptions[0].neg_accompression = 0;
386
387    lcp_allowoptions[0].neg_asyncmap = 0;
388    lcp_wantoptions[0].neg_asyncmap = 0;
389
390    lcp_allowoptions[0].neg_pcompression = 0;
391    lcp_wantoptions[0].neg_pcompression = 0;
392
393    if (lcp_allowoptions[0].mru > MAX_PPPOE_MTU)
394	lcp_allowoptions[0].mru = MAX_PPPOE_MTU;
395    if (lcp_wantoptions[0].mru > MAX_PPPOE_MTU)
396	lcp_wantoptions[0].mru = MAX_PPPOE_MTU;
397
398    ccp_allowoptions[0].deflate = 0;
399    ccp_wantoptions[0].deflate = 0;
400
401    ipcp_allowoptions[0].neg_vj = 0;
402    ipcp_wantoptions[0].neg_vj = 0;
403
404    ccp_allowoptions[0].bsd_compress = 0;
405    ccp_wantoptions[0].bsd_compress = 0;
406}
407
408struct channel pppoe_channel = {
409    options: Options,
410    process_extra_options: &PPPOEDeviceOptions,
411    check_options: pppoe_check_options,
412    connect: &PPPOEConnectDevice,
413    disconnect: &PPPOEDisconnectDevice,
414    establish_ppp: &generic_establish_ppp,
415    disestablish_ppp: &generic_disestablish_ppp,
416    send_config: NULL,
417    recv_config: &PPPOERecvConfig,
418    close: NULL,
419    cleanup: NULL
420};
421