FreeBSD-5.3/libexec/pppoed/pppoed.c
/*-
* Copyright (c) 1999-2001 Brian Somers <brian@Awfulhak.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD: src/libexec/pppoed/pppoed.c,v 1.23 2003/11/15 15:26:34 harti Exp $
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <netgraph.h>
#include <net/ethernet.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netgraph/ng_ether.h>
#include <netgraph/ng_message.h>
#include <netgraph/ng_pppoe.h>
#include <netgraph/ng_socket.h>
#include <errno.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <sys/fcntl.h>
#ifndef NOKLDLOAD
#include <sys/linker.h>
#include <sys/module.h>
#endif
#include <sys/uio.h>
#include <sys/wait.h>
#include <syslog.h>
#include <termios.h>
#include <unistd.h>
#define DEFAULT_EXEC_PREFIX "exec /usr/sbin/ppp -direct "
#define HISMACADDR "HISMACADDR"
#define SESSION_ID "SESSION_ID"
static void nglogx(const char *, ...) __printflike(1, 2);
static int ReceivedSignal;
static int
usage(const char *prog)
{
fprintf(stderr, "usage: %s [-Fd] [-P pidfile] [-a name] [-e exec | -l label]"
" [-p provider] interface\n", prog);
return EX_USAGE;
}
static void
Farewell(int sig)
{
ReceivedSignal = sig;
}
static int
ConfigureNode(const char *prog, const char *iface, const char *provider,
int cs, int ds, int debug, struct ngm_connect *ngc)
{
/*
* We're going to do this with the passed `ds' & `cs' descriptors:
*
* .---------.
* | ether |
* | <iface> |
* `---------'
* (orphan) ds cs
* | | |
* | | |
* (ethernet) | |
* .---------. .-----------.
* | pppoe | | socket |
* | <iface> |(pppoe-<pid>)<---->(pppoe-<pid>)| <unnamed> |
* `--------- `-----------'
* (exec-<pid>)
* ^ .-----------. .-------------.
* | | socket | | ppp -direct |
* `--->(exec-<pid>)| <unnamed> |--fd--| provider |
* `-----------' `-------------'
*
* where there are potentially many ppp processes running off of the
* same PPPoE node.
* The exec-<pid> hook isn't made 'till we Spawn().
*/
char *epath, *spath;
struct ngpppoe_init_data *data;
const struct hooklist *hlist;
const struct nodeinfo *ninfo;
const struct linkinfo *nlink;
struct ngm_mkpeer mkp;
struct ng_mesg *resp;
u_char rbuf[2048];
int f, plen;
/*
* Ask for a list of hooks attached to the "ether" node. This node should
* magically exist as a way of hooking stuff onto an ethernet device
*/
epath = (char *)alloca(strlen(iface) + 2);
sprintf(epath, "%s:", iface);
if (debug)
fprintf(stderr, "Sending NGM_LISTHOOKS to %s\n", epath);
if (NgSendMsg(cs, epath, NGM_GENERIC_COOKIE, NGM_LISTHOOKS, NULL, 0) < 0) {
if (errno == ENOENT)
fprintf(stderr, "%s Cannot send a netgraph message: Invalid interface\n",
epath);
else
fprintf(stderr, "%s Cannot send a netgraph message: %s\n",
epath, strerror(errno));
return EX_UNAVAILABLE;
}
/* Get our list back */
resp = (struct ng_mesg *)rbuf;
if (NgRecvMsg(cs, resp, sizeof rbuf, NULL) <= 0) {
perror("Cannot get netgraph response");
return EX_UNAVAILABLE;
}
hlist = (const struct hooklist *)resp->data;
ninfo = &hlist->nodeinfo;
if (debug)
fprintf(stderr, "Got reply from id [%x]: Type %s with %d hooks\n",
ninfo->id, ninfo->type, ninfo->hooks);
/* Make sure we've got the right type of node */
if (strncmp(ninfo->type, NG_ETHER_NODE_TYPE, sizeof NG_ETHER_NODE_TYPE - 1)) {
fprintf(stderr, "%s Unexpected node type ``%s'' (wanted ``"
NG_ETHER_NODE_TYPE "'')\n", epath, ninfo->type);
return EX_DATAERR;
}
/* look for a hook already attached. */
for (f = 0; f < ninfo->hooks; f++) {
nlink = &hlist->link[f];
if (debug)
fprintf(stderr, " Got [%x]:%s -> [%x]:%s\n", ninfo->id,
nlink->ourhook, nlink->nodeinfo.id, nlink->peerhook);
if (!strcmp(nlink->ourhook, NG_ETHER_HOOK_ORPHAN) ||
!strcmp(nlink->ourhook, NG_ETHER_HOOK_DIVERT)) {
/*
* Something is using the data coming out of this `ether' node.
* If it's a PPPoE node, we use that node, otherwise we complain that
* someone else is using the node.
*/
if (strcmp(nlink->nodeinfo.type, NG_PPPOE_NODE_TYPE)) {
fprintf(stderr, "%s Node type %s is currently active\n",
epath, nlink->nodeinfo.type);
return EX_UNAVAILABLE;
}
break;
}
}
if (f == ninfo->hooks) {
/*
* Create a new PPPoE node connected to the `ether' node using
* the magic `orphan' and `ethernet' hooks
*/
snprintf(mkp.type, sizeof mkp.type, "%s", NG_PPPOE_NODE_TYPE);
snprintf(mkp.ourhook, sizeof mkp.ourhook, "%s", NG_ETHER_HOOK_ORPHAN);
snprintf(mkp.peerhook, sizeof mkp.peerhook, "%s", NG_PPPOE_HOOK_ETHERNET);
if (debug)
fprintf(stderr, "Send MKPEER: %s%s -> [type %s]:%s\n", epath,
mkp.ourhook, mkp.type, mkp.peerhook);
if (NgSendMsg(cs, epath, NGM_GENERIC_COOKIE,
NGM_MKPEER, &mkp, sizeof mkp) < 0) {
fprintf(stderr, "%s Cannot create a peer PPPoE node: %s\n",
epath, strerror(errno));
return EX_OSERR;
}
}
/* Connect the PPPoE node to our socket node. */
snprintf(ngc->path, sizeof ngc->path, "%s%s", epath, NG_ETHER_HOOK_ORPHAN);
snprintf(ngc->ourhook, sizeof ngc->ourhook, "pppoe-%ld", (long)getpid());
memcpy(ngc->peerhook, ngc->ourhook, sizeof ngc->peerhook);
if (NgSendMsg(cs, ".:", NGM_GENERIC_COOKIE,
NGM_CONNECT, ngc, sizeof *ngc) < 0) {
perror("Cannot CONNECT PPPoE and socket nodes");
return EX_OSERR;
}
plen = strlen(provider);
data = (struct ngpppoe_init_data *)alloca(sizeof *data + plen);
snprintf(data->hook, sizeof data->hook, "%s", ngc->peerhook);
memcpy(data->data, provider, plen);
data->data_len = plen;
spath = (char *)alloca(strlen(ngc->peerhook) + 3);
strcpy(spath, ".:");
strcpy(spath + 2, ngc->ourhook);
if (debug) {
if (provider)
fprintf(stderr, "Sending PPPOE_LISTEN to %s, provider %s\n",
spath, provider);
else
fprintf(stderr, "Sending PPPOE_LISTEN to %s\n", spath);
}
if (NgSendMsg(cs, spath, NGM_PPPOE_COOKIE, NGM_PPPOE_LISTEN,
data, sizeof *data + plen) == -1) {
fprintf(stderr, "%s: Cannot LISTEN on netgraph node: %s\n",
spath, strerror(errno));
return EX_OSERR;
}
return 0;
}
static void
Spawn(const char *prog, const char *acname, const char *provider,
const char *exec, struct ngm_connect ngc, int cs, int ds, void *request,
int sz, int debug)
{
char msgbuf[sizeof(struct ng_mesg) + sizeof(struct ngpppoe_sts)];
struct ng_mesg *rep = (struct ng_mesg *)msgbuf;
struct ngpppoe_sts *sts = (struct ngpppoe_sts *)(msgbuf + sizeof *rep);
struct ngpppoe_init_data *data;
char env[sizeof(HISMACADDR)+18], unknown[14], sessionid[5], *path;
unsigned char *macaddr;
const char *msg;
int ret, slen;
switch ((ret = fork())) {
case -1:
syslog(LOG_ERR, "fork: %m");
break;
case 0:
switch (fork()) {
case 0:
break;
case -1:
_exit(errno);
default:
_exit(0);
}
close(cs);
close(ds);
/* Create a new socket node */
if (debug)
syslog(LOG_INFO, "Creating a new socket node");
if (NgMkSockNode(NULL, &cs, &ds) == -1) {
syslog(LOG_ERR, "Cannot create netgraph socket node: %m");
_exit(EX_CANTCREAT);
}
/* Connect the PPPoE node to our new socket node. */
snprintf(ngc.ourhook, sizeof ngc.ourhook, "exec-%ld", (long)getpid());
memcpy(ngc.peerhook, ngc.ourhook, sizeof ngc.peerhook);
if (debug)
syslog(LOG_INFO, "Sending CONNECT from .:%s -> %s.%s",
ngc.ourhook, ngc.path, ngc.peerhook);
if (NgSendMsg(cs, ".:", NGM_GENERIC_COOKIE,
NGM_CONNECT, &ngc, sizeof ngc) < 0) {
syslog(LOG_ERR, "Cannot CONNECT PPPoE and socket nodes: %m");
_exit(EX_OSERR);
}
/*
* If we tell the socket node not to LINGER, it will go away when
* the last hook is removed.
*/
if (debug)
syslog(LOG_INFO, "Sending NGM_SOCK_CMD_NOLINGER to socket");
if (NgSendMsg(cs, ".:", NGM_SOCKET_COOKIE,
NGM_SOCK_CMD_NOLINGER, NULL, 0) < 0) {
syslog(LOG_ERR, "Cannot send NGM_SOCK_CMD_NOLINGER: %m");
_exit(EX_OSERR);
}
/* Put the PPPoE node into OFFER mode */
slen = strlen(acname);
data = (struct ngpppoe_init_data *)alloca(sizeof *data + slen);
snprintf(data->hook, sizeof data->hook, "%s", ngc.ourhook);
memcpy(data->data, acname, slen);
data->data_len = slen;
path = (char *)alloca(strlen(ngc.ourhook) + 3);
strcpy(path, ".:");
strcpy(path + 2, ngc.ourhook);
syslog(LOG_INFO, "Offering to %s as access concentrator %s",
path, acname);
if (NgSendMsg(cs, path, NGM_PPPOE_COOKIE, NGM_PPPOE_OFFER,
data, sizeof *data + slen) == -1) {
syslog(LOG_INFO, "%s: Cannot OFFER on netgraph node: %m", path);
_exit(EX_OSERR);
}
/* If we have a provider code, set it */
if (provider) {
slen = strlen(provider);
data = (struct ngpppoe_init_data *)alloca(sizeof *data + slen);
snprintf(data->hook, sizeof data->hook, "%s", ngc.ourhook);
memcpy(data->data, provider, slen);
data->data_len = slen;
syslog(LOG_INFO, "adding to %s as offered service %s",
path, acname);
if (NgSendMsg(cs, path, NGM_PPPOE_COOKIE, NGM_PPPOE_SERVICE,
data, sizeof *data + slen) == -1) {
syslog(LOG_INFO, "%s: Cannot add service on netgraph node: %m", path);
_exit(EX_OSERR);
}
}
/* Put the peer's MAC address in the environment */
if (sz >= sizeof(struct ether_header)) {
macaddr = ((struct ether_header *)request)->ether_shost;
snprintf(env, sizeof(env), "%s=%x:%x:%x:%x:%x:%x", HISMACADDR,
macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4],
macaddr[5]);
if (putenv(env) != 0)
syslog(LOG_INFO, "putenv: cannot set %s: %m", env);
}
/* And send our request data to the waiting node */
if (debug)
syslog(LOG_INFO, "Sending original request to %s (%d bytes)", path, sz);
if (NgSendData(ds, ngc.ourhook, request, sz) == -1) {
syslog(LOG_ERR, "Cannot send original request to %s: %m", path);
_exit(EX_OSERR);
}
/* Then wait for a success indication */
if (debug)
syslog(LOG_INFO, "Waiting for a SUCCESS reply %s", path);
do {
if ((ret = NgRecvMsg(cs, rep, sizeof msgbuf, NULL)) < 0) {
syslog(LOG_ERR, "%s: Cannot receive a message: %m", path);
_exit(EX_OSERR);
}
if (ret == 0) {
/* The socket has been closed */
syslog(LOG_INFO, "%s: Client timed out", path);
_exit(EX_TEMPFAIL);
}
if (rep->header.version != NG_VERSION) {
syslog(LOG_ERR, "%ld: Unexpected netgraph version, expected %ld",
(long)rep->header.version, (long)NG_VERSION);
_exit(EX_PROTOCOL);
}
if (rep->header.typecookie != NGM_PPPOE_COOKIE) {
syslog(LOG_INFO, "%ld: Unexpected netgraph cookie, expected %ld",
(long)rep->header.typecookie, (long)NGM_PPPOE_COOKIE);
continue;
}
switch (rep->header.cmd) {
case NGM_PPPOE_SET_FLAG: msg = "SET_FLAG"; break;
case NGM_PPPOE_CONNECT: msg = "CONNECT"; break;
case NGM_PPPOE_LISTEN: msg = "LISTEN"; break;
case NGM_PPPOE_OFFER: msg = "OFFER"; break;
case NGM_PPPOE_SUCCESS: msg = "SUCCESS"; break;
case NGM_PPPOE_FAIL: msg = "FAIL"; break;
case NGM_PPPOE_CLOSE: msg = "CLOSE"; break;
case NGM_PPPOE_GET_STATUS: msg = "GET_STATUS"; break;
case NGM_PPPOE_ACNAME:
msg = "ACNAME";
if (setenv("ACNAME", sts->hook, 1) != 0)
syslog(LOG_WARNING, "setenv: cannot set ACNAME=%s: %m",
sts->hook);
break;
case NGM_PPPOE_SESSIONID:
msg = "SESSIONID";
snprintf(sessionid, sizeof sessionid, "%04x", *(u_int16_t *)sts);
if (setenv("SESSIONID", sessionid, 1) != 0)
syslog(LOG_WARNING, "setenv: cannot set SESSIONID=%s: %m",
sessionid);
break;
default:
snprintf(unknown, sizeof unknown, "<%d>", (int)rep->header.cmd);
msg = unknown;
break;
}
switch (rep->header.cmd) {
case NGM_PPPOE_FAIL:
case NGM_PPPOE_CLOSE:
syslog(LOG_ERR, "Received NGM_PPPOE_%s (hook \"%s\")",
msg, sts->hook);
_exit(0);
}
syslog(LOG_INFO, "Received NGM_PPPOE_%s (hook \"%s\")", msg, sts->hook);
} while (rep->header.cmd != NGM_PPPOE_SUCCESS);
dup2(ds, STDIN_FILENO);
dup2(ds, STDOUT_FILENO);
close(ds);
close(cs);
setsid();
syslog(LOG_INFO, "Executing: %s", exec);
execlp(_PATH_BSHELL, _PATH_BSHELL, "-c", exec, (char *)NULL);
syslog(LOG_ERR, "execlp failed: %m");
_exit(EX_OSFILE);
default:
wait(&ret);
errno = ret;
if (errno)
syslog(LOG_ERR, "Second fork failed: %m");
break;
}
}
#ifndef NOKLDLOAD
static int
LoadModules(void)
{
const char *module[] = { "netgraph", "ng_socket", "ng_ether", "ng_pppoe" };
int f;
for (f = 0; f < sizeof module / sizeof *module; f++)
if (modfind(module[f]) == -1 && kldload(module[f]) == -1) {
fprintf(stderr, "kldload: %s: %s\n", module[f], strerror(errno));
return 0;
}
return 1;
}
#endif
static void
nglog(const char *fmt, ...)
{
char nfmt[256];
va_list ap;
snprintf(nfmt, sizeof nfmt, "%s: %s", fmt, strerror(errno));
va_start(ap, fmt);
vsyslog(LOG_INFO, nfmt, ap);
va_end(ap);
}
static void
nglogx(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vsyslog(LOG_INFO, fmt, ap);
va_end(ap);
}
int
main(int argc, char *argv[])
{
char hostname[MAXHOSTNAMELEN], *exec, rhook[NG_HOOKSIZ];
unsigned char response[1024];
const char *label, *prog, *provider, *acname;
struct ngm_connect ngc;
struct sigaction act;
int ch, cs, ds, ret, optF, optd, optn, sz, f;
const char *pidfile;
prog = strrchr(argv[0], '/');
prog = prog ? prog + 1 : argv[0];
pidfile = NULL;
exec = NULL;
label = NULL;
acname = NULL;
provider = "";
optF = optd = optn = 0;
while ((ch = getopt(argc, argv, "FP:a:de:l:n:p:")) != -1) {
switch (ch) {
case 'F':
optF = 1;
break;
case 'P':
pidfile = optarg;
break;
case 'a':
acname = optarg;
break;
case 'd':
optd = 1;
break;
case 'e':
exec = optarg;
break;
case 'l':
label = optarg;
break;
case 'n':
optn = 1;
NgSetDebug(atoi(optarg));
break;
case 'p':
provider = optarg;
break;
default:
return usage(prog);
}
}
if (optind >= argc || optind + 2 < argc)
return usage(prog);
if (exec != NULL && label != NULL)
return usage(prog);
if (exec == NULL) {
if (label == NULL)
label = provider;
if (label == NULL) {
fprintf(stderr, "%s: Either a provider, a label or an exec command"
" must be given\n", prog);
return usage(prog);
}
exec = (char *)alloca(sizeof DEFAULT_EXEC_PREFIX + strlen(label));
if (exec == NULL) {
fprintf(stderr, "%s: Cannot allocate %d bytes\n", prog,
(int)(sizeof DEFAULT_EXEC_PREFIX) + strlen(label));
return EX_OSERR;
}
strcpy(exec, DEFAULT_EXEC_PREFIX);
strcpy(exec + sizeof DEFAULT_EXEC_PREFIX - 1, label);
}
if (acname == NULL) {
char *dot;
if (gethostname(hostname, sizeof hostname))
strcpy(hostname, "localhost");
else if ((dot = strchr(hostname, '.')))
*dot = '\0';
acname = hostname;
}
#ifndef NOKLDLOAD
if (!LoadModules())
return EX_UNAVAILABLE;
#endif
/* Create a socket node */
if (NgMkSockNode(NULL, &cs, &ds) == -1) {
perror("Cannot create netgraph socket node");
return EX_CANTCREAT;
}
/* Connect it up (and fill in `ngc') */
if ((ret = ConfigureNode(prog, argv[optind], provider, cs, ds,
optd, &ngc)) != 0) {
close(cs);
close(ds);
return ret;
}
if (!optF && daemon(1, 0) == -1) {
perror("daemon()");
close(cs);
close(ds);
return EX_OSERR;
}
if (pidfile != NULL) {
FILE *fp;
if ((fp = fopen(pidfile, "w")) == NULL) {
perror(pidfile);
close(cs);
close(ds);
return EX_CANTCREAT;
} else {
fprintf(fp, "%d\n", (int)getpid());
fclose(fp);
}
}
openlog(prog, LOG_PID | (optF ? LOG_PERROR : 0), LOG_DAEMON);
if (!optF && optn)
NgSetErrLog(nglog, nglogx);
memset(&act, '\0', sizeof act);
act.sa_handler = Farewell;
act.sa_flags = 0;
sigemptyset(&act.sa_mask);
sigaction(SIGHUP, &act, NULL);
sigaction(SIGINT, &act, NULL);
sigaction(SIGQUIT, &act, NULL);
sigaction(SIGTERM, &act, NULL);
while (!ReceivedSignal) {
if (*provider)
syslog(LOG_INFO, "Listening as provider %s", provider);
else
syslog(LOG_INFO, "Listening");
switch (sz = NgRecvData(ds, response, sizeof response, rhook)) {
case -1:
syslog(LOG_INFO, "NgRecvData: %m");
break;
case 0:
syslog(LOG_INFO, "NgRecvData: socket closed");
break;
default:
if (optd) {
char *dbuf, *ptr;
ptr = dbuf = alloca(sz * 2 + 1);
for (f = 0; f < sz; f++, ptr += 2)
sprintf(ptr, "%02x", (u_char)response[f]);
*ptr = '\0';
syslog(LOG_INFO, "Got %d bytes of data: %s", sz, dbuf);
}
}
if (sz <= 0) {
ret = EX_UNAVAILABLE;
break;
}
Spawn(prog, acname, provider, exec, ngc, cs, ds, response, sz, optd);
}
if (pidfile)
remove(pidfile);
if (ReceivedSignal) {
syslog(LOG_INFO, "Received signal %d, exiting", ReceivedSignal);
signal(ReceivedSignal, SIG_DFL);
raise(ReceivedSignal);
/* NOTREACHED */
ret = -ReceivedSignal;
}
return ret;
}