freebsd-dev/usr.sbin/ppp/chat.c

793 lines
20 KiB
C

/*-
* Copyright (c) 1998 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.
*
* $Id: chat.c,v 1.44.2.28 1998/05/01 19:22:14 brian Exp $
*/
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <sys/un.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <termios.h>
#include <unistd.h>
#include "mbuf.h"
#include "log.h"
#include "defs.h"
#include "timer.h"
#include "lqr.h"
#include "hdlc.h"
#include "throughput.h"
#include "fsm.h"
#include "lcp.h"
#include "ccp.h"
#include "link.h"
#include "async.h"
#include "descriptor.h"
#include "physical.h"
#include "chat.h"
#include "mp.h"
#include "auth.h"
#include "chap.h"
#include "slcompress.h"
#include "iplist.h"
#include "ipcp.h"
#include "filter.h"
#include "datalink.h"
#include "bundle.h"
#define BUFLEFT(c) (sizeof (c)->buf - ((c)->bufend - (c)->buf))
#define issep(c) ((c) == '\t' || (c) == ' ')
static void ExecStr(struct physical *, char *, char *, int);
static char *ExpandString(struct chat *, const char *, char *, int, int);
static void
chat_PauseTimer(void *v)
{
struct chat *c = (struct chat *)v;
timer_Stop(&c->pause);
c->pause.load = 0;
}
static void
chat_Pause(struct chat *c, u_long load)
{
timer_Stop(&c->pause);
c->pause.load += load;
c->pause.func = chat_PauseTimer;
c->pause.name = "chat pause";
c->pause.arg = c;
timer_Start(&c->pause);
}
static void
chat_TimeoutTimer(void *v)
{
struct chat *c = (struct chat *)v;
timer_Stop(&c->timeout);
c->TimedOut = 1;
}
static void
chat_SetTimeout(struct chat *c)
{
timer_Stop(&c->timeout);
if (c->TimeoutSec > 0) {
c->timeout.load = SECTICKS * c->TimeoutSec;
c->timeout.func = chat_TimeoutTimer;
c->timeout.name = "chat timeout";
c->timeout.arg = c;
timer_Start(&c->timeout);
}
}
static char *
chat_NextChar(char *ptr, char ch)
{
for (; *ptr; ptr++)
if (*ptr == ch)
return ptr;
else if (*ptr == '\\')
if (*++ptr == '\0')
return NULL;
return NULL;
}
static int
chat_UpdateSet(struct descriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n)
{
struct chat *c = descriptor2chat(d);
int special, gotabort, gottimeout, needcr;
int TimedOut = c->TimedOut;
static char arg_term;
if (c->pause.state == TIMER_RUNNING)
return 0;
if (TimedOut) {
log_Printf(LogCHAT, "Expect timeout\n");
if (c->nargptr == NULL)
c->state = CHAT_FAILED;
else {
/* c->state = CHAT_EXPECT; */
c->argptr = &arg_term;
}
c->TimedOut = 0;
}
if (c->state != CHAT_EXPECT && c->state != CHAT_SEND)
return 0;
gottimeout = gotabort = 0;
if (c->arg < c->argc && (c->arg < 0 || *c->argptr == '\0')) {
/* Go get the next string */
if (c->arg < 0 || c->state == CHAT_SEND)
c->state = CHAT_EXPECT;
else
c->state = CHAT_SEND;
special = 1;
while (special && (c->nargptr || c->arg < c->argc - 1)) {
if (c->arg < 0 || (!TimedOut && c->state == CHAT_SEND))
c->nargptr = NULL;
if (c->nargptr != NULL) {
/* We're doing expect-send-expect.... */
c->argptr = c->nargptr;
/* Put the '-' back in case we ever want to rerun our script */
c->nargptr[-1] = '-';
c->nargptr = chat_NextChar(c->nargptr, '-');
if (c->nargptr != NULL)
*c->nargptr++ = '\0';
} else {
int minus;
c->argptr = c->argv[++c->arg];
if (c->state == CHAT_EXPECT) {
/* Look for expect-send-expect sequence */
c->nargptr = c->argptr;
minus = 0;
while ((c->nargptr = chat_NextChar(c->nargptr, '-'))) {
c->nargptr++;
minus++;
}
if (minus % 2)
log_Printf(LogWARN, "chat_UpdateSet: \"%s\": Uneven number of"
" '-' chars, all ignored\n", c->argptr);
else if (minus) {
c->nargptr = chat_NextChar(c->argptr, '-');
*c->nargptr++ = '\0';
}
}
}
/*
* c->argptr now temporarily points into c->script (via c->argv)
* If it's an expect-send-expect sequence, we've just got the correct
* portion of that sequence.
*/
needcr = c->state == CHAT_SEND && *c->argptr != '!';
/* We leave room for a potential HDLC header in the target string */
ExpandString(c, c->argptr, c->exp + 2, sizeof c->exp - 2, needcr);
if (gotabort) {
if (c->abort.num < MAXABORTS) {
int len, i;
len = strlen(c->exp+2);
for (i = 0; i < c->abort.num; i++)
if (len > c->abort.string[i].len) {
int last;
for (last = c->abort.num; last > i; last--) {
c->abort.string[last].data = c->abort.string[last-1].data;
c->abort.string[last].len = c->abort.string[last-1].len;
}
break;
}
c->abort.string[i].len = len;
c->abort.string[i].data = (char *)malloc(len+1);
memcpy(c->abort.string[i].data, c->exp+2, len+1);
c->abort.num++;
} else
log_Printf(LogERROR, "chat_UpdateSet: too many abort strings\n");
gotabort = 0;
} else if (gottimeout) {
c->TimeoutSec = atoi(c->exp + 2);
if (c->TimeoutSec <= 0)
c->TimeoutSec = 30;
gottimeout = 0;
} else if (c->nargptr == NULL && !strcmp(c->exp+2, "ABORT"))
gotabort = 1;
else if (c->nargptr == NULL && !strcmp(c->exp+2, "TIMEOUT"))
gottimeout = 1;
else {
if (c->exp[2] == '!')
ExecStr(c->physical, c->exp + 3, c->exp + 2, sizeof c->exp - 2);
if (c->exp[2] == '\0') {
/* Empty string, reparse (this may be better as a `goto start') */
c->argptr = &arg_term;
return chat_UpdateSet(d, r, w, e, n);
}
special = 0;
}
}
if (special) {
if (gottimeout)
log_Printf(LogWARN, "chat_UpdateSet: TIMEOUT: Argument expected\n");
else if (gotabort)
log_Printf(LogWARN, "chat_UpdateSet: ABORT: Argument expected\n");
/* End of script - all ok */
c->state = CHAT_DONE;
return 0;
}
/* set c->argptr to point in the right place */
c->argptr = c->exp + 2;
c->arglen = strlen(c->argptr);
if (c->state == CHAT_EXPECT) {
/* We must check to see if the string's already been found ! */
char *begin, *end;
end = c->bufend - c->arglen + 1;
if (end < c->bufstart)
end = c->bufstart;
for (begin = c->bufstart; begin < end; begin++)
if (!strncmp(begin, c->argptr, c->arglen)) {
c->bufstart = begin + c->arglen;
c->argptr += c->arglen;
c->arglen = 0;
/* Continue - we've already read our expect string */
return chat_UpdateSet(d, r, w, e, n);
}
log_Printf(LogCHAT, "Expect(%d): %s\n", c->TimeoutSec, c->argptr);
chat_SetTimeout(c);
}
}
/*
* We now have c->argptr pointing at what we want to expect/send and
* c->state saying what we want to do... we now know what to put in
* the fd_set :-)
*/
if (c->state == CHAT_EXPECT)
return physical_UpdateSet(&c->physical->desc, r, NULL, e, n, 1);
else
return physical_UpdateSet(&c->physical->desc, NULL, w, e, n, 1);
}
static int
chat_IsSet(struct descriptor *d, const fd_set *fdset)
{
struct chat *c = descriptor2chat(d);
return physical_IsSet(&c->physical->desc, fdset);
}
static void
chat_UpdateLog(struct chat *c, int in)
{
if (log_IsKept(LogCHAT) || log_IsKept(LogCONNECT)) {
/*
* If a linefeed appears in the last `in' characters of `c's input
* buffer, output from there, all the way back to the last linefeed.
* This is called for every read of `in' bytes.
*/
char *ptr, *end, *stop, ch;
int level;
level = log_IsKept(LogCHAT) ? LogCHAT : LogCONNECT;
if (in == -1)
end = ptr = c->bufend;
else {
ptr = c->bufend - in;
for (end = c->bufend - 1; end >= ptr; end--)
if (*end == '\n')
break;
}
if (end >= ptr) {
for (ptr = c->bufend - (in == -1 ? 1 : in + 1); ptr >= c->bufstart; ptr--)
if (*ptr == '\n')
break;
ptr++;
stop = NULL;
while (stop < end) {
if ((stop = memchr(ptr, '\n', end - ptr)) == NULL)
stop = end;
ch = *stop;
*stop = '\0';
if (level == LogCHAT || strstr(ptr, "CONNECT"))
log_Printf(level, "Received: %s\n", ptr);
*stop = ch;
ptr = stop + 1;
}
}
}
}
static void
chat_Read(struct descriptor *d, struct bundle *bundle, const fd_set *fdset)
{
struct chat *c = descriptor2chat(d);
if (c->state == CHAT_EXPECT) {
ssize_t in;
char *abegin, *ebegin, *begin, *aend, *eend, *end;
int n;
/*
* XXX - should this read only 1 byte to guarantee that we don't
* swallow any ppp talk from the peer ?
*/
in = BUFLEFT(c);
if (in > sizeof c->buf / 2)
in = sizeof c->buf / 2;
in = physical_Read(c->physical, c->bufend, in);
if (in <= 0)
return;
/* `begin' and `end' delimit where we're going to strncmp() from */
ebegin = c->bufend - c->arglen + 1;
eend = ebegin + in;
if (ebegin < c->bufstart)
ebegin = c->bufstart;
if (c->abort.num) {
abegin = c->bufend - c->abort.string[0].len + 1;
aend = c->bufend - c->abort.string[c->abort.num-1].len + in + 1;
if (abegin < c->bufstart)
abegin = c->bufstart;
} else {
abegin = ebegin;
aend = eend;
}
begin = abegin < ebegin ? abegin : ebegin;
end = aend < eend ? eend : aend;
c->bufend += in;
chat_UpdateLog(c, in);
if (c->bufend > c->buf + sizeof c->buf / 2) {
/* Shuffle our receive buffer back a bit */
int chop;
for (chop = begin - c->buf; chop; chop--)
if (c->buf[chop] == '\n')
/* found some already-logged garbage to remove :-) */
break;
if (!chop)
chop = begin - c->buf;
if (chop) {
char *from, *to;
to = c->buf;
from = to + chop;
while (from < c->bufend)
*to++ = *from++;
c->bufstart -= chop;
c->bufend -= chop;
begin -= chop;
end -= chop;
abegin -= chop;
aend -= chop;
ebegin -= chop;
eend -= chop;
}
}
for (; begin < end; begin++)
if (begin >= ebegin && begin < eend &&
!strncmp(begin, c->argptr, c->arglen)) {
/* Got it ! */
if (memchr(begin + c->arglen - 1, '\n',
c->bufend - begin - c->arglen + 1) == NULL) {
/* force it into the log */
end = c->bufend;
c->bufend = begin + c->arglen;
chat_UpdateLog(c, -1);
c->bufend = end;
}
c->bufstart = begin + c->arglen;
c->argptr += c->arglen;
c->arglen = 0;
break;
} else if (begin >= abegin && begin < aend) {
for (n = c->abort.num - 1; n >= 0; n--) {
if (begin + c->abort.string[n].len > c->bufend)
break;
if (!strncmp(begin, c->abort.string[n].data,
c->abort.string[n].len)) {
if (memchr(begin + c->abort.string[n].len - 1, '\n',
c->bufend - begin - c->abort.string[n].len + 1) == NULL) {
/* force it into the log */
end = c->bufend;
c->bufend = begin + c->abort.string[n].len;
chat_UpdateLog(c, -1);
c->bufend = end;
}
c->bufstart = begin + c->abort.string[n].len;
c->state = CHAT_FAILED;
return;
}
}
}
}
}
static void
chat_Write(struct descriptor *d, struct bundle *bundle, const fd_set *fdset)
{
struct chat *c = descriptor2chat(d);
if (c->state == CHAT_SEND) {
int wrote;
if (strstr(c->argv[c->arg], "\\P")) /* Don't log the password */
log_Printf(LogCHAT, "Send: %s\n", c->argv[c->arg]);
else {
int sz;
sz = c->arglen - 1;
while (sz >= 0 && c->argptr[sz] == '\n')
sz--;
log_Printf(LogCHAT, "Send: %.*s\n", sz + 1, c->argptr);
}
if (physical_IsSync(c->physical)) {
/* There's always room for the HDLC header */
c->argptr -= 2;
c->arglen += 2;
memcpy(c->argptr, "\377\003", 2); /* Prepend HDLC header */
}
wrote = physical_Write(c->physical, c->argptr, c->arglen);
if (wrote == -1) {
if (errno != EINTR)
log_Printf(LogERROR, "chat_Write: %s\n", strerror(errno));
if (physical_IsSync(c->physical)) {
c->argptr += 2;
c->arglen -= 2;
}
} else if (wrote < 2 && physical_IsSync(c->physical)) {
/* Oops - didn't even write our HDLC header ! */
c->argptr += 2;
c->arglen -= 2;
} else {
c->argptr += wrote;
c->arglen -= wrote;
}
}
}
void
chat_Init(struct chat *c, struct physical *p, const char *data, int emptybuf,
const char *phone)
{
c->desc.type = CHAT_DESCRIPTOR;
c->desc.next = NULL;
c->desc.UpdateSet = chat_UpdateSet;
c->desc.IsSet = chat_IsSet;
c->desc.Read = chat_Read;
c->desc.Write = chat_Write;
c->physical = p;
c->state = CHAT_EXPECT;
if (data == NULL) {
*c->script = '\0';
c->argc = 0;
} else {
strncpy(c->script, data, sizeof c->script - 1);
c->script[sizeof c->script - 1] = '\0';
c->argc = MakeArgs(c->script, c->argv, VECSIZE(c->argv));
}
c->arg = -1;
c->argptr = NULL;
c->nargptr = NULL;
if (emptybuf)
c->bufstart = c->bufend = c->buf;
c->TimeoutSec = 30;
c->TimedOut = 0;
c->phone = phone;
c->abort.num = 0;
memset(&c->pause, '\0', sizeof c->pause);
memset(&c->timeout, '\0', sizeof c->timeout);
}
void
chat_Destroy(struct chat *c)
{
timer_Stop(&c->pause);
timer_Stop(&c->timeout);
while (c->abort.num)
free(c->abort.string[--c->abort.num].data);
c->abort.num = 0;
}
static char *
findblank(char *p, int instring)
{
if (instring) {
while (*p) {
if (*p == '\\') {
strcpy(p, p + 1);
if (!*p)
break;
} else if (*p == '"')
return (p);
p++;
}
} else {
while (*p) {
if (issep(*p))
return (p);
p++;
}
}
return p;
}
int
MakeArgs(char *script, char **pvect, int maxargs)
{
int nargs, nb;
int instring;
nargs = 0;
while (*script) {
nb = strspn(script, " \t");
script += nb;
if (*script) {
if (*script == '"') {
instring = 1;
script++;
if (*script == '\0')
break; /* Shouldn't return here. Need to null
* terminate below */
} else
instring = 0;
if (nargs >= maxargs - 1)
break;
*pvect++ = script;
nargs++;
script = findblank(script, instring);
if (*script)
*script++ = '\0';
}
}
*pvect = NULL;
return nargs;
}
/*
* \c don't add a cr
* \d Sleep a little (delay 2 seconds
* \n Line feed character
* \P Auth Key password
* \p pause 0.25 sec
* \r Carrige return character
* \s Space character
* \T Telephone number(s) (defined via `set phone')
* \t Tab character
* \U Auth User
*/
static char *
ExpandString(struct chat *c, const char *str, char *result, int reslen,
int sendmode)
{
int addcr = 0;
result[--reslen] = '\0';
if (sendmode)
addcr = 1;
while (*str && reslen > 0) {
switch (*str) {
case '\\':
str++;
switch (*str) {
case 'c':
if (sendmode)
addcr = 0;
break;
case 'd': /* Delay 2 seconds */
chat_Pause(c, 2 * SECTICKS);
break;
case 'p':
chat_Pause(c, SECTICKS / 4);
break; /* Pause 0.25 sec */
case 'n':
*result++ = '\n';
reslen--;
break;
case 'r':
*result++ = '\r';
reslen--;
break;
case 's':
*result++ = ' ';
reslen--;
break;
case 't':
*result++ = '\t';
reslen--;
break;
case 'P':
strncpy(result, c->physical->dl->bundle->cfg.auth.key, reslen);
reslen -= strlen(result);
result += strlen(result);
break;
case 'T':
strncpy(result, c->phone, reslen);
reslen -= strlen(result);
result += strlen(result);
break;
case 'U':
strncpy(result, c->physical->dl->bundle->cfg.auth.name, reslen);
reslen -= strlen(result);
result += strlen(result);
break;
default:
reslen--;
*result++ = *str;
break;
}
if (*str)
str++;
break;
case '^':
str++;
if (*str) {
*result++ = *str++ & 0x1f;
reslen--;
}
break;
default:
*result++ = *str++;
reslen--;
break;
}
}
if (--reslen > 0) {
if (addcr)
*result++ = '\r';
}
if (--reslen > 0)
*result++ = '\0';
return (result);
}
static void
ExecStr(struct physical *physical, char *command, char *out, int olen)
{
pid_t pid;
int fids[2];
char *vector[MAXARGS], *startout, *endout;
int stat, nb;
log_Printf(LogCHAT, "Exec: %s\n", command);
MakeArgs(command, vector, VECSIZE(vector));
if (pipe(fids) < 0) {
log_Printf(LogCHAT, "Unable to create pipe in ExecStr: %s\n",
strerror(errno));
*out = '\0';
return;
}
if ((pid = fork()) == 0) {
timer_TermService();
fids[1] = fcntl(fids[1], F_DUPFD, 4);
dup2(physical_GetFD(physical), STDIN_FILENO);
dup2(STDIN_FILENO, STDOUT_FILENO);
dup2(fids[1], STDERR_FILENO);
close(3);
if (open(_PATH_TTY, O_RDWR) == 3)
fcntl(3, F_SETFD, 0); /* Clear close-on-exec flag */
else
fcntl(3, F_SETFD, 1); /* Set close-on-exec flag */
setuid(geteuid());
execvp(vector[0], vector);
fprintf(stderr, "execvp failed: %s: %s\n", vector[0], strerror(errno));
exit(127);
} else {
char *name = strdup(vector[0]);
close(fids[1]);
endout = out + olen - 1;
startout = out;
while (out < endout) {
nb = read(fids[0], out, 1);
if (nb <= 0)
break;
out++;
}
*out = '\0';
close(fids[0]);
close(fids[1]);
waitpid(pid, &stat, WNOHANG);
if (WIFSIGNALED(stat)) {
log_Printf(LogWARN, "%s: signal %d\n", name, WTERMSIG(stat));
free(name);
*out = '\0';
return;
} else if (WIFEXITED(stat)) {
switch (WEXITSTATUS(stat)) {
case 0:
free(name);
break;
case 127:
log_Printf(LogWARN, "%s: %s\n", name, startout);
free(name);
*out = '\0';
return;
break;
default:
log_Printf(LogWARN, "%s: exit %d\n", name, WEXITSTATUS(stat));
free(name);
*out = '\0';
return;
break;
}
} else {
log_Printf(LogWARN, "%s: Unexpected exit result\n", name);
free(name);
*out = '\0';
return;
}
}
}