/*
* cbcp - Call Back Configuration Protocol.
*
* Copyright (c) 1995 Pedro Roque Marques. 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.
*
* 3. The names of the authors of this software must not be used to
* endorse or promote products derived from this software without
* prior written permission.
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Pedro Roque Marques
* <pedro_m@yahoo.com>"
*
* THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#define RCSID "$Id: cbcp.c,v 1.16 2004/10/28 00:15:36 paulus Exp $"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include "pppd.h"
#include "cbcp.h"
#include "fsm.h"
#include "lcp.h"
static const char rcsid[] = RCSID;
/*
* Options.
*/
static int setcbcp __P((char **));
static option_t cbcp_option_list[] = {
{ "callback", o_special, (void *)setcbcp,
"Ask for callback", OPT_PRIO | OPT_A2STRVAL, &cbcp[0].us_number },
{ NULL }
};
/*
* Protocol entry points.
*/
static void cbcp_init __P((int unit));
static void cbcp_open __P((int unit));
static void cbcp_lowerup __P((int unit));
static void cbcp_input __P((int unit, u_char *pkt, int len));
static void cbcp_protrej __P((int unit));
static int cbcp_printpkt __P((u_char *pkt, int len,
void (*printer) __P((void *, char *, ...)),
void *arg));
struct protent cbcp_protent = {
PPP_CBCP,
cbcp_init,
cbcp_input,
cbcp_protrej,
cbcp_lowerup,
NULL,
cbcp_open,
NULL,
cbcp_printpkt,
NULL,
0,
"CBCP",
NULL,
cbcp_option_list,
NULL,
NULL,
NULL
};
cbcp_state cbcp[NUM_PPP];
/* internal prototypes */
static void cbcp_recvreq __P((cbcp_state *us, u_char *pckt, int len));
static void cbcp_resp __P((cbcp_state *us));
static void cbcp_up __P((cbcp_state *us));
static void cbcp_recvack __P((cbcp_state *us, u_char *pckt, int len));
static void cbcp_send __P((cbcp_state *us, int code, u_char *buf, int len));
/* option processing */
static int
setcbcp(argv)
char **argv;
{
lcp_wantoptions[0].neg_cbcp = 1;
cbcp_protent.enabled_flag = 1;
cbcp[0].us_number = strdup(*argv);
if (cbcp[0].us_number == 0)
novm("callback number");
cbcp[0].us_type |= (1 << CB_CONF_USER);
cbcp[0].us_type |= (1 << CB_CONF_ADMIN);
return (1);
}
/* init state */
static void
cbcp_init(iface)
int iface;
{
cbcp_state *us;
us = &cbcp[iface];
memset(us, 0, sizeof(cbcp_state));
us->us_unit = iface;
us->us_type |= (1 << CB_CONF_NO);
}
/* lower layer is up */
static void
cbcp_lowerup(iface)
int iface;
{
cbcp_state *us = &cbcp[iface];
dbglog("cbcp_lowerup");
dbglog("want: %d", us->us_type);
if (us->us_type == CB_CONF_USER)
dbglog("phone no: %s", us->us_number);
}
static void
cbcp_open(unit)
int unit;
{
dbglog("cbcp_open");
}
/* process an incomming packet */
static void
cbcp_input(unit, inpacket, pktlen)
int unit;
u_char *inpacket;
int pktlen;
{
u_char *inp;
u_char code, id;
u_short len;
cbcp_state *us = &cbcp[unit];
inp = inpacket;
if (pktlen < CBCP_MINLEN) {
if (debug)
dbglog("CBCP packet is too small");
return;
}
GETCHAR(code, inp);
GETCHAR(id, inp);
GETSHORT(len, inp);
if (len > pktlen || len < CBCP_MINLEN) {
if (debug)
dbglog("CBCP packet: invalid length %d", len);
return;
}
len -= CBCP_MINLEN;
switch(code) {
case CBCP_REQ:
us->us_id = id;
cbcp_recvreq(us, inp, len);
break;
case CBCP_RESP:
if (debug)
dbglog("CBCP_RESP received");
break;
case CBCP_ACK:
if (debug && id != us->us_id)
dbglog("id doesn't match: expected %d recv %d",
us->us_id, id);
cbcp_recvack(us, inp, len);
break;
default:
break;
}
}
/* protocol was rejected by foe */
void cbcp_protrej(int iface)
{
}
char *cbcp_codenames[] = {
"Request", "Response", "Ack"
};
char *cbcp_optionnames[] = {
"NoCallback",
"UserDefined",
"AdminDefined",
"List"
};
/* pretty print a packet */
static int
cbcp_printpkt(p, plen, printer, arg)
u_char *p;
int plen;
void (*printer) __P((void *, char *, ...));
void *arg;
{
int code, opt, id, len, olen, delay;
u_char *pstart;
if (plen < HEADERLEN)
return 0;
pstart = p;
GETCHAR(code, p);
GETCHAR(id, p);
GETSHORT(len, p);
if (len < HEADERLEN || len > plen)
return 0;
if (code >= 1 && code <= sizeof(cbcp_codenames) / sizeof(char *))
printer(arg, " %s", cbcp_codenames[code-1]);
else
printer(arg, " code=0x%x", code);
printer(arg, " id=0x%x", id);
len -= HEADERLEN;
switch (code) {
case CBCP_REQ:
case CBCP_RESP:
case CBCP_ACK:
while(len >= 2) {
GETCHAR(opt, p);
GETCHAR(olen, p);
if (olen < 2 || olen > len) {
break;
}
printer(arg, " <");
len -= olen;
if (opt >= 1 && opt <= sizeof(cbcp_optionnames) / sizeof(char *))
printer(arg, " %s", cbcp_optionnames[opt-1]);
else
printer(arg, " option=0x%x", opt);
if (olen > 2) {
GETCHAR(delay, p);
printer(arg, " delay = %d", delay);
}
if (olen > 3) {
int addrt;
char str[256];
GETCHAR(addrt, p);
memcpy(str, p, olen - 4);
str[olen - 4] = 0;
printer(arg, " number = %s", str);
}
printer(arg, ">");
}
break;
default:
break;
}
for (; len > 0; --len) {
GETCHAR(code, p);
printer(arg, " %.2x", code);
}
return p - pstart;
}
/* received CBCP request */
static void
cbcp_recvreq(us, pckt, pcktlen)
cbcp_state *us;
u_char *pckt;
int pcktlen;
{
u_char type, opt_len, delay, addr_type;
char address[256];
int len = pcktlen;
address[0] = 0;
while (len >= 2) {
dbglog("length: %d", len);
GETCHAR(type, pckt);
GETCHAR(opt_len, pckt);
if (opt_len < 2 || opt_len > len)
break;
if (opt_len > 2)
GETCHAR(delay, pckt);
us->us_allowed |= (1 << type);
switch(type) {
case CB_CONF_NO:
dbglog("no callback allowed");
break;
case CB_CONF_USER:
dbglog("user callback allowed");
if (opt_len > 4) {
GETCHAR(addr_type, pckt);
memcpy(address, pckt, opt_len - 4);
address[opt_len - 4] = 0;
if (address[0])
dbglog("address: %s", address);
}
break;
case CB_CONF_ADMIN:
dbglog("user admin defined allowed");
break;
case CB_CONF_LIST:
break;
}
len -= opt_len;
}
if (len != 0) {
if (debug)
dbglog("cbcp_recvreq: malformed packet (%d bytes left)", len);
return;
}
cbcp_resp(us);
}
static void
cbcp_resp(us)
cbcp_state *us;
{
u_char cb_type;
u_char buf[256];
u_char *bufp = buf;
int len = 0;
int slen;
cb_type = us->us_allowed & us->us_type;
dbglog("cbcp_resp cb_type=%d", cb_type);
#if 0
if (!cb_type)
lcp_down(us->us_unit);
#endif
if (cb_type & ( 1 << CB_CONF_USER ) ) {
dbglog("cbcp_resp CONF_USER");
slen = strlen(us->us_number);
if (slen > 250) {
warn("callback number truncated to 250 characters");
slen = 250;
}
PUTCHAR(CB_CONF_USER, bufp);
len = 3 + 1 + slen + 1;
PUTCHAR(len , bufp);
PUTCHAR(5, bufp); /* delay */
PUTCHAR(1, bufp);
BCOPY(us->us_number, bufp, slen + 1);
cbcp_send(us, CBCP_RESP, buf, len);
return;
}
if (cb_type & ( 1 << CB_CONF_ADMIN ) ) {
dbglog("cbcp_resp CONF_ADMIN");
PUTCHAR(CB_CONF_ADMIN, bufp);
len = 3;
PUTCHAR(len, bufp);
PUTCHAR(5, bufp); /* delay */
cbcp_send(us, CBCP_RESP, buf, len);
return;
}
if (cb_type & ( 1 << CB_CONF_NO ) ) {
dbglog("cbcp_resp CONF_NO");
PUTCHAR(CB_CONF_NO, bufp);
len = 2;
PUTCHAR(len , bufp);
cbcp_send(us, CBCP_RESP, buf, len);
start_networks(us->us_unit);
return;
}
}
static void
cbcp_send(us, code, buf, len)
cbcp_state *us;
int code;
u_char *buf;
int len;
{
u_char *outp;
int outlen;
outp = outpacket_buf;
outlen = 4 + len;
MAKEHEADER(outp, PPP_CBCP);
PUTCHAR(code, outp);
PUTCHAR(us->us_id, outp);
PUTSHORT(outlen, outp);
if (len)
BCOPY(buf, outp, len);
output(us->us_unit, outpacket_buf, outlen + PPP_HDRLEN);
}
static void
cbcp_recvack(us, pckt, len)
cbcp_state *us;
u_char *pckt;
int len;
{
u_char type, delay, addr_type;
int opt_len;
char address[256];
if (len >= 2) {
GETCHAR(type, pckt);
GETCHAR(opt_len, pckt);
if (opt_len >= 2 && opt_len <= len) {
if (opt_len > 2)
GETCHAR(delay, pckt);
if (opt_len > 4) {
GETCHAR(addr_type, pckt);
memcpy(address, pckt, opt_len - 4);
address[opt_len - 4] = 0;
if (address[0])
dbglog("peer will call: %s", address);
}
if (type == CB_CONF_NO)
return;
cbcp_up(us);
} else if (debug)
dbglog("cbcp_recvack: malformed packet");
}
}
/* ok peer will do callback */
static void
cbcp_up(us)
cbcp_state *us;
{
persist = 0;
lcp_close(0, "Call me back, please");
status = EXIT_CALLBACK;
}