pppd/plugins/rp-pppoe/plugin.c

   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 1.13 2005/07/09 09:12:48 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
  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
 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
 185 PPPOERecvConfig(int mru,
 186                 u_int32_t asyncmap,
 187                 int pcomp,
 188                 int accomp)
 189 {
 190     if (mru > MAX_PPPOE_MTU)
 191         warn("Couldn't increase MRU to %d", mru);
 192 }
 193
 194 /**********************************************************************
 195  * %FUNCTION: PPPOEDisconnectDevice
 196  * %ARGUMENTS:
 197  * None
 198  * %RETURNS:
 199  * Nothing
 200  * %DESCRIPTION:
 201  * Disconnects PPPoE device
 202  ***********************************************************************/
 203 static void
 204 PPPOEDisconnectDevice(void)
 205 {
 206     struct sockaddr_pppox sp;
 207
 208     sp.sa_family = AF_PPPOX;
 209     sp.sa_protocol = PX_PROTO_OE;
 210     sp.sa_addr.pppoe.sid = 0;
 211     memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
 212     memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
 213     if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
 214                 sizeof(struct sockaddr_pppox)) < 0) {
 215         fatal("Failed to disconnect PPPoE socket: %d %m", errno);
 216         return;
 217     }
 218     close(conn->sessionSocket);
 219     /* don't send PADT?? */
 220     close(conn->discoverySocket);
 221 }
 222
 223 static void
 224 PPPOEDeviceOptions(void)
 225 {
 226     char buf[256];
 227     snprintf(buf, 256, _PATH_ETHOPT "%s",devnam);
 228     if(!options_from_file(buf, 0, 0, 1))
 229         exit(EXIT_OPTION_ERROR);
 230
 231 }
 232
 233 struct channel pppoe_channel;
 234
 235 /**********************************************************************
 236  * %FUNCTION: PPPoEDevnameHook
 237  * %ARGUMENTS:
 238  * cmd -- the command (actually, the device name
 239  * argv -- argument vector
 240  * doit -- if non-zero, set device name.  Otherwise, just check if possible
 241  * %RETURNS:
 242  * 1 if we will handle this device; 0 otherwise.
 243  * %DESCRIPTION:
 244  * Checks if name is a valid interface name; if so, returns 1.  Also
 245  * sets up devnam (string representation of device).
 246  ***********************************************************************/
 247 static int
 248 PPPoEDevnameHook(char *cmd, char **argv, int doit)
 249 {
 250     int r = 1;
 251     int fd;
 252     struct ifreq ifr;
 253
 254     /* Only do it if name is "ethXXX", "nasXXX", "tapXXX" or "nic-XXXX.
 255        In latter case strip off the "nic-" */
 256     /* Thanks to Russ Couturier for this fix */
 257     if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
 258         /* Strip off "nic-" */
 259         cmd += 4;
 260     } else if (strlen(cmd) < 4
 261                || (strncmp(cmd, "eth", 3) && strncmp(cmd, "nas", 3)
 262                    && strncmp(cmd, "tap", 3) && strncmp(cmd, "br", 2))) {
 263         return 0;
 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                     error("Interface %s not Ethernet", cmd);
 282                     r=0;
 283                 }
 284             }
 285         }
 286     }
 287
 288     /* Close socket */
 289     close(fd);
 290     if (r) {
 291         strncpy(devnam, cmd, sizeof(devnam));
 292         if (the_channel != &pppoe_channel) {
 293
 294             the_channel = &pppoe_channel;
 295             modem = 0;
 296
 297             lcp_allowoptions[0].neg_accompression = 0;
 298             lcp_wantoptions[0].neg_accompression = 0;
 299
 300             lcp_allowoptions[0].neg_asyncmap = 0;
 301             lcp_wantoptions[0].neg_asyncmap = 0;
 302
 303             lcp_allowoptions[0].neg_pcompression = 0;
 304             lcp_wantoptions[0].neg_pcompression = 0;
 305
 306             lcp_allowoptions[0].mru = MAX_PPPOE_MTU;
 307             lcp_wantoptions[0].mru = MAX_PPPOE_MTU;
 308
 309             ccp_allowoptions[0].deflate = 0 ;
 310             ccp_wantoptions[0].deflate = 0 ;
 311
 312             ipcp_allowoptions[0].neg_vj=0;
 313             ipcp_wantoptions[0].neg_vj=0;
 314
 315             ccp_allowoptions[0].bsd_compress = 0;
 316             ccp_wantoptions[0].bsd_compress = 0;
 317
 318             PPPOEInitDevice();
 319         }
 320         return 1;
 321     }
 322
 323     return r;
 324 }
 325
 326 /**********************************************************************
 327  * %FUNCTION: plugin_init
 328  * %ARGUMENTS:
 329  * None
 330  * %RETURNS:
 331  * Nothing
 332  * %DESCRIPTION:
 333  * Initializes hooks for pppd plugin
 334  ***********************************************************************/
 335 void
 336 plugin_init(void)
 337 {
 338     if (!ppp_available() && !new_style_driver) {
 339         fatal("Linux kernel does not support PPPoE -- are you running 2.4.x?");
 340     }
 341
 342     add_options(Options);
 343
 344     info("RP-PPPoE plugin version %s compiled against pppd %s",
 345          RP_VERSION, VERSION);
 346 }
 347
 348 /**********************************************************************
 349 *%FUNCTION: fatalSys
 350 *%ARGUMENTS:
 351 * str -- error message
 352 *%RETURNS:
 353 * Nothing
 354 *%DESCRIPTION:
 355 * Prints a message plus the errno value to stderr and syslog and exits.
 356 ***********************************************************************/
 357 void
 358 fatalSys(char const *str)
 359 {
 360     char buf[1024];
 361     int i = errno;
 362     sprintf(buf, "%.256s: %.256s", str, strerror(i));
 363     printErr(buf);
 364     sprintf(buf, "RP-PPPoE: %.256s: %.256s", str, strerror(i));
 365     sendPADT(conn, buf);
 366     exit(1);
 367 }
 368
 369 /**********************************************************************
 370 *%FUNCTION: rp_fatal
 371 *%ARGUMENTS:
 372 * str -- error message
 373 *%RETURNS:
 374 * Nothing
 375 *%DESCRIPTION:
 376 * Prints a message to stderr and syslog and exits.
 377 ***********************************************************************/
 378 void
 379 rp_fatal(char const *str)
 380 {
 381     char buf[1024];
 382     printErr(str);
 383     sprintf(buf, "RP-PPPoE: %.256s", str);
 384     sendPADT(conn, buf);
 385     exit(1);
 386 }
 387 /**********************************************************************
 388 *%FUNCTION: sysErr
 389 *%ARGUMENTS:
 390 * str -- error message
 391 *%RETURNS:
 392 * Nothing
 393 *%DESCRIPTION:
 394 * Prints a message plus the errno value to syslog.
 395 ***********************************************************************/
 396 void
 397 sysErr(char const *str)
 398 {
 399     rp_fatal(str);
 400 }
 401
 402
 403 struct channel pppoe_channel = {
 404     options: Options,
 405     process_extra_options: &PPPOEDeviceOptions,
 406     check_options: NULL,
 407     connect: &PPPOEConnectDevice,
 408     disconnect: &PPPOEDisconnectDevice,
 409     establish_ppp: &generic_establish_ppp,
 410     disestablish_ppp: &generic_disestablish_ppp,
 411     send_config: NULL,
 412     recv_config: &PPPOERecvConfig,
 413     close: NULL,
 414     cleanup: NULL
 415 };