/***********************************************************************
*
* plugin.c
*
* pppd plugin for kernel-mode PPPoE on Linux
*
* Copyright (C) 2001 by Roaring Penguin Software Inc., Michal Ostrowski
* and Jamal Hadi Salim.
*
* Much code and many ideas derived from pppoe plugin by Michal
* Ostrowski and Jamal Hadi Salim, which carries this copyright:
*
* Copyright 2000 Michal Ostrowski <mostrows@styx.uwaterloo.ca>,
* Jamal Hadi Salim <hadi@cyberus.ca>
* Borrows heavily from the PPPoATM plugin by Mitchell Blank Jr.,
* which is based in part on work from Jens Axboe and Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
***********************************************************************/
static char const RCSID[] =
"$Id: plugin.c,v 1.17 2008/06/15 04:35:50 paulus Exp $";
#define _GNU_SOURCE 1
#include "pppoe.h"
#include "pppd/pppd.h"
#include "pppd/fsm.h"
#include "pppd/lcp.h"
#include "pppd/ipcp.h"
#include "pppd/ccp.h"
/* #include "pppd/pathnames.h" */
#include <linux/types.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <net/ethernet.h>
#include <net/if_arp.h>
#include <linux/ppp_defs.h>
#include <linux/if_pppox.h>
#ifndef _ROOT_PATH
#define _ROOT_PATH ""
#endif
#define _PATH_ETHOPT _ROOT_PATH "/etc/ppp/options."
char pppd_version[] = VERSION;
/* From sys-linux.c in pppd -- MUST FIX THIS! */
extern int new_style_driver;
char *pppd_pppoe_service = NULL;
static char *acName = NULL;
static char *existingSession = NULL;
static int printACNames = 0;
static char *pppoe_reqd_mac = NULL;
unsigned char pppoe_reqd_mac_addr[6];
static int PPPoEDevnameHook(char *cmd, char **argv, int doit);
static option_t Options[] = {
{ "device name", o_wild, (void *) &PPPoEDevnameHook,
"PPPoE device name",
OPT_DEVNAM | OPT_PRIVFIX | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC,
devnam},
{ "rp_pppoe_service", o_string, &pppd_pppoe_service,
"Desired PPPoE service name" },
{ "rp_pppoe_ac", o_string, &acName,
"Desired PPPoE access concentrator name" },
{ "rp_pppoe_sess", o_string, &existingSession,
"Attach to existing session (sessid:macaddr)" },
{ "rp_pppoe_verbose", o_int, &printACNames,
"Be verbose about discovered access concentrators"},
{ "pppoe-mac", o_string, &pppoe_reqd_mac,
"Only connect to specified MAC address" },
{ NULL }
};
int (*OldDevnameHook)(char *cmd, char **argv, int doit) = NULL;
static PPPoEConnection *conn = NULL;
/**********************************************************************
* %FUNCTION: PPPOEInitDevice
* %ARGUMENTS:
* None
* %RETURNS:
*
* %DESCRIPTION:
* Initializes PPPoE device.
***********************************************************************/
static int
PPPOEInitDevice(void)
{
conn = malloc(sizeof(PPPoEConnection));
if (!conn) {
novm("PPPoE session data");
}
memset(conn, 0, sizeof(PPPoEConnection));
conn->ifName = devnam;
conn->discoverySocket = -1;
conn->sessionSocket = -1;
conn->useHostUniq = 1;
conn->printACNames = printACNames;
conn->discoveryTimeout = PADI_TIMEOUT;
return 1;
}
/**********************************************************************
* %FUNCTION: PPPOEConnectDevice
* %ARGUMENTS:
* None
* %RETURNS:
* Non-negative if all goes well; -1 otherwise
* %DESCRIPTION:
* Connects PPPoE device.
***********************************************************************/
static int
PPPOEConnectDevice(void)
{
struct sockaddr_pppox sp;
struct ifreq ifr;
int s;
/* Open session socket before discovery phase, to avoid losing session */
/* packets sent by peer just after PADS packet (noted on some Cisco */
/* server equipment). */
/* Opening this socket just before waitForPADS in the discovery() */
/* function would be more appropriate, but it would mess-up the code */
conn->sessionSocket = socket(AF_PPPOX, SOCK_STREAM, PX_PROTO_OE);
if (conn->sessionSocket < 0) {
error("Failed to create PPPoE socket: %m");
return -1;
}
/* Restore configuration */
lcp_allowoptions[0].mru = conn->mtu;
lcp_wantoptions[0].mru = conn->mru;
/* Update maximum MRU */
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s < 0) {
error("Can't get MTU for %s: %m", conn->ifName);
goto errout;
}
strncpy(ifr.ifr_name, conn->ifName, sizeof(ifr.ifr_name));
if (ioctl(s, SIOCGIFMTU, &ifr) < 0) {
error("Can't get MTU for %s: %m", conn->ifName);
close(s);
goto errout;
}
close(s);
if (lcp_allowoptions[0].mru > ifr.ifr_mtu - TOTAL_OVERHEAD)
lcp_allowoptions[0].mru = ifr.ifr_mtu - TOTAL_OVERHEAD;
if (lcp_wantoptions[0].mru > ifr.ifr_mtu - TOTAL_OVERHEAD)
lcp_wantoptions[0].mru = ifr.ifr_mtu - TOTAL_OVERHEAD;
conn->acName = acName;
conn->serviceName = pppd_pppoe_service;
strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam));
if (existingSession) {
unsigned int mac[ETH_ALEN];
int i, ses;
if (sscanf(existingSession, "%d:%x:%x:%x:%x:%x:%x",
&ses, &mac[0], &mac[1], &mac[2],
&mac[3], &mac[4], &mac[5]) != 7) {
fatal("Illegal value for rp_pppoe_sess option");
}
conn->session = htons(ses);
for (i=0; i<ETH_ALEN; i++) {
conn->peerEth[i] = (unsigned char) mac[i];
}
} else {
conn->discoverySocket =
openInterface(conn->ifName, Eth_PPPOE_Discovery, conn->myEth);
discovery(conn);
if (conn->discoveryState != STATE_SESSION) {
error("Unable to complete PPPoE Discovery");
goto errout;
}
}
/* Set PPPoE session-number for further consumption */
ppp_session_number = ntohs(conn->session);
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OE;
sp.sa_addr.pppoe.sid = conn->session;
memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
/* Set remote_number for ServPoET */
sprintf(remote_number, "%02X:%02X:%02X:%02X:%02X:%02X",
(unsigned) conn->peerEth[0],
(unsigned) conn->peerEth[1],
(unsigned) conn->peerEth[2],
(unsigned) conn->peerEth[3],
(unsigned) conn->peerEth[4],
(unsigned) conn->peerEth[5]);
warn("Connected to %02X:%02X:%02X:%02X:%02X:%02X via interface %s",
(unsigned) conn->peerEth[0],
(unsigned) conn->peerEth[1],
(unsigned) conn->peerEth[2],
(unsigned) conn->peerEth[3],
(unsigned) conn->peerEth[4],
(unsigned) conn->peerEth[5],
conn->ifName);
script_setenv("MACREMOTE", remote_number, 0);
if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
sizeof(struct sockaddr_pppox)) < 0) {
error("Failed to connect PPPoE socket: %d %m", errno);
goto errout;
}
return conn->sessionSocket;
errout:
if (conn->discoverySocket >= 0) {
sendPADT(conn, NULL);
close(conn->discoverySocket);
conn->discoverySocket = -1;
}
close(conn->sessionSocket);
return -1;
}
static void
PPPOERecvConfig(int mru,
u_int32_t asyncmap,
int pcomp,
int accomp)
{
#if 0 /* broken protocol, but no point harrassing the users I guess... */
if (mru > MAX_PPPOE_MTU)
warn("Couldn't increase MRU to %d", mru);
#endif
}
/**********************************************************************
* %FUNCTION: PPPOEDisconnectDevice
* %ARGUMENTS:
* None
* %RETURNS:
* Nothing
* %DESCRIPTION:
* Disconnects PPPoE device
***********************************************************************/
static void
PPPOEDisconnectDevice(void)
{
struct sockaddr_pppox sp;
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OE;
sp.sa_addr.pppoe.sid = 0;
memcpy(sp.sa_addr.pppoe.dev, conn->ifName, IFNAMSIZ);
memcpy(sp.sa_addr.pppoe.remote, conn->peerEth, ETH_ALEN);
if (connect(conn->sessionSocket, (struct sockaddr *) &sp,
sizeof(struct sockaddr_pppox)) < 0)
error("Failed to disconnect PPPoE socket: %d %m", errno);
close(conn->sessionSocket);
/* don't send PADT?? */
if (conn->discoverySocket >= 0)
close(conn->discoverySocket);
}
static void
PPPOEDeviceOptions(void)
{
char buf[256];
snprintf(buf, 256, _PATH_ETHOPT "%s", devnam);
if (!options_from_file(buf, 0, 0, 1))
exit(EXIT_OPTION_ERROR);
}
struct channel pppoe_channel;
/**********************************************************************
* %FUNCTION: PPPoEDevnameHook
* %ARGUMENTS:
* cmd -- the command (actually, the device name
* argv -- argument vector
* doit -- if non-zero, set device name. Otherwise, just check if possible
* %RETURNS:
* 1 if we will handle this device; 0 otherwise.
* %DESCRIPTION:
* Checks if name is a valid interface name; if so, returns 1. Also
* sets up devnam (string representation of device).
***********************************************************************/
static int
PPPoEDevnameHook(char *cmd, char **argv, int doit)
{
int r = 1;
int fd;
struct ifreq ifr;
/*
* Take any otherwise-unrecognized option as a possible device name,
* and test if it is the name of a network interface with a
* hardware address whose sa_family is ARPHRD_ETHER.
*/
if (strlen(cmd) > 4 && !strncmp(cmd, "nic-", 4)) {
/* Strip off "nic-" */
cmd += 4;
}
/* Open a socket */
if ((fd = socket(PF_PACKET, SOCK_RAW, 0)) < 0) {
r = 0;
}
/* Try getting interface index */
if (r) {
strncpy(ifr.ifr_name, cmd, sizeof(ifr.ifr_name));
if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
r = 0;
} else {
if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
r = 0;
} else {
if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
if (doit)
error("Interface %s not Ethernet", cmd);
r = 0;
}
}
}
}
/* Close socket */
close(fd);
if (r && doit) {
strncpy(devnam, cmd, sizeof(devnam));
if (the_channel != &pppoe_channel) {
the_channel = &pppoe_channel;
modem = 0;
PPPOEInitDevice();
}
return 1;
}
return r;
}
/**********************************************************************
* %FUNCTION: plugin_init
* %ARGUMENTS:
* None
* %RETURNS:
* Nothing
* %DESCRIPTION:
* Initializes hooks for pppd plugin
***********************************************************************/
void
plugin_init(void)
{
if (!ppp_available() && !new_style_driver) {
fatal("Linux kernel does not support PPPoE -- are you running 2.4.x?");
}
add_options(Options);
info("RP-PPPoE plugin version %s compiled against pppd %s",
RP_VERSION, VERSION);
}
void pppoe_check_options(void)
{
unsigned int mac[6];
int i;
if (pppoe_reqd_mac != NULL) {
if (sscanf(pppoe_reqd_mac, "%x:%x:%x:%x:%x:%x",
&mac[0], &mac[1], &mac[2], &mac[3],
&mac[4], &mac[5]) != 6) {
option_error("cannot parse pppoe-mac option value");
exit(EXIT_OPTION_ERROR);
}
for (i = 0; i < 6; ++i)
conn->req_peer_mac[i] = mac[i];
conn->req_peer = 1;
}
lcp_allowoptions[0].neg_accompression = 0;
lcp_wantoptions[0].neg_accompression = 0;
lcp_allowoptions[0].neg_asyncmap = 0;
lcp_wantoptions[0].neg_asyncmap = 0;
lcp_allowoptions[0].neg_pcompression = 0;
lcp_wantoptions[0].neg_pcompression = 0;
if (lcp_allowoptions[0].mru > MAX_PPPOE_MTU)
lcp_allowoptions[0].mru = MAX_PPPOE_MTU;
if (lcp_wantoptions[0].mru > MAX_PPPOE_MTU)
lcp_wantoptions[0].mru = MAX_PPPOE_MTU;
/* Save configuration */
conn->mtu = lcp_allowoptions[0].mru;
conn->mru = lcp_wantoptions[0].mru;
ccp_allowoptions[0].deflate = 0;
ccp_wantoptions[0].deflate = 0;
ipcp_allowoptions[0].neg_vj = 0;
ipcp_wantoptions[0].neg_vj = 0;
ccp_allowoptions[0].bsd_compress = 0;
ccp_wantoptions[0].bsd_compress = 0;
}
struct channel pppoe_channel = {
.options = Options,
.process_extra_options = &PPPOEDeviceOptions,
.check_options = pppoe_check_options,
.connect = &PPPOEConnectDevice,
.disconnect = &PPPOEDisconnectDevice,
.establish_ppp = &generic_establish_ppp,
.disestablish_ppp = &generic_disestablish_ppp,
.send_config = NULL,
.recv_config = &PPPOERecvConfig,
.close = NULL,
.cleanup = NULL
};