freebsd-dev/libexec/pppoed/pppoed.c
Sean Farley 2966d28c32 Significantly reduce the memory leak as noted in BUGS section for
setenv(3) by tracking the size of the memory allocated instead of using
strlen() on the current value.

Convert all calls to POSIX from historic BSD API:
 - unsetenv returns an int.
 - putenv takes a char * instead of const char *.
 - putenv no longer makes a copy of the input string.
 - errno is set appropriately for POSIX.  Exceptions involve bad environ
   variable and internal initialization code.  These both set errno to
   EFAULT.

Several patches to base utilities to handle the POSIX changes from
Andrey Chernov's previous commit.  A few I re-wrote to use setenv()
instead of putenv().

New regression module for tools/regression/environ to test these
functions.  It also can be used to test the performance.

Bump __FreeBSD_version to 700050 due to API change.

PR:		kern/99826
Approved by:	wes
Approved by:	re (kensmith)
2007-07-04 00:00:41 +00:00

693 lines
20 KiB
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.
*
* $FreeBSD$
*/
#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]"
" [-n ngdebug] [-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[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), "%x:%x:%x:%x:%x:%x",
macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4],
macaddr[5]);
if (setenv(HISMACADDR, env, 1) != 0)
syslog(LOG_INFO, "setenv: cannot set %s: %m", HISMACADDR);
}
/* 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;
}