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minix/lib/liblwip/netif/ppp/ipcp.c
Tomas Hruby abab24b785 LWIP - liblwip 
lwip-1.4.0-rc1 imported as liblwip
2011-04-07 07:43:36 +00:00

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/** In contrast to pppd 2.3.1, DNS support has been added, proxy-ARP and
dial-on-demand has been stripped. */
/*****************************************************************************
* ipcp.c - Network PPP IP Control Protocol program file.
*
* Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
* portions Copyright (c) 1997 by Global Election Systems Inc.
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice and the following disclaimer are included verbatim in any
* distributions. No written agreement, license, or royalty fee is required
* for any of the authorized uses.
*
* THIS SOFTWARE IS PROVIDED BY THE 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 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.
*
******************************************************************************
* REVISION HISTORY
*
* 03-01-01 Marc Boucher <marc@mbsi.ca>
* Ported to lwIP.
* 97-12-08 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
* Original.
*****************************************************************************/
/*
* ipcp.c - PPP IP Control Protocol.
*
* Copyright (c) 1989 Carnegie Mellon University.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by Carnegie Mellon University. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include "lwip/opt.h"
#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
#include "ppp.h"
#include "pppdebug.h"
#include "auth.h"
#include "fsm.h"
#include "vj.h"
#include "ipcp.h"
#include "lwip/inet.h"
#include <string.h>
/* #define OLD_CI_ADDRS 1 */ /* Support deprecated address negotiation. */
/* global vars */
ipcp_options ipcp_wantoptions[NUM_PPP]; /* Options that we want to request */
ipcp_options ipcp_gotoptions[NUM_PPP]; /* Options that peer ack'd */
ipcp_options ipcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */
ipcp_options ipcp_hisoptions[NUM_PPP]; /* Options that we ack'd */
/* local vars */
static int default_route_set[NUM_PPP]; /* Have set up a default route */
static int cis_received[NUM_PPP]; /* # Conf-Reqs received */
/*
* Callbacks for fsm code. (CI = Configuration Information)
*/
static void ipcp_resetci (fsm *); /* Reset our CI */
static int ipcp_cilen (fsm *); /* Return length of our CI */
static void ipcp_addci (fsm *, u_char *, int *); /* Add our CI */
static int ipcp_ackci (fsm *, u_char *, int); /* Peer ack'd our CI */
static int ipcp_nakci (fsm *, u_char *, int); /* Peer nak'd our CI */
static int ipcp_rejci (fsm *, u_char *, int); /* Peer rej'd our CI */
static int ipcp_reqci (fsm *, u_char *, int *, int); /* Rcv CI */
static void ipcp_up (fsm *); /* We're UP */
static void ipcp_down (fsm *); /* We're DOWN */
#if PPP_ADDITIONAL_CALLBACKS
static void ipcp_script (fsm *, char *); /* Run an up/down script */
#endif
static void ipcp_finished (fsm *); /* Don't need lower layer */
fsm ipcp_fsm[NUM_PPP]; /* IPCP fsm structure */
static fsm_callbacks ipcp_callbacks = { /* IPCP callback routines */
ipcp_resetci, /* Reset our Configuration Information */
ipcp_cilen, /* Length of our Configuration Information */
ipcp_addci, /* Add our Configuration Information */
ipcp_ackci, /* ACK our Configuration Information */
ipcp_nakci, /* NAK our Configuration Information */
ipcp_rejci, /* Reject our Configuration Information */
ipcp_reqci, /* Request peer's Configuration Information */
ipcp_up, /* Called when fsm reaches LS_OPENED state */
ipcp_down, /* Called when fsm leaves LS_OPENED state */
NULL, /* Called when we want the lower layer up */
ipcp_finished, /* Called when we want the lower layer down */
NULL, /* Called when Protocol-Reject received */
NULL, /* Retransmission is necessary */
NULL, /* Called to handle protocol-specific codes */
"IPCP" /* String name of protocol */
};
/*
* Protocol entry points from main code.
*/
static void ipcp_init (int);
static void ipcp_open (int);
static void ipcp_close (int, char *);
static void ipcp_lowerup (int);
static void ipcp_lowerdown (int);
static void ipcp_input (int, u_char *, int);
static void ipcp_protrej (int);
struct protent ipcp_protent = {
PPP_IPCP,
ipcp_init,
ipcp_input,
ipcp_protrej,
ipcp_lowerup,
ipcp_lowerdown,
ipcp_open,
ipcp_close,
#if PPP_ADDITIONAL_CALLBACKS
ipcp_printpkt,
NULL,
#endif /* PPP_ADDITIONAL_CALLBACKS */
1,
"IPCP",
#if PPP_ADDITIONAL_CALLBACKS
ip_check_options,
NULL,
ip_active_pkt
#endif /* PPP_ADDITIONAL_CALLBACKS */
};
static void ipcp_clear_addrs (int);
/*
* Lengths of configuration options.
*/
#define CILEN_VOID 2
#define CILEN_COMPRESS 4 /* min length for compression protocol opt. */
#define CILEN_VJ 6 /* length for RFC1332 Van-Jacobson opt. */
#define CILEN_ADDR 6 /* new-style single address option */
#define CILEN_ADDRS 10 /* old-style dual address option */
#define CODENAME(x) ((x) == CONFACK ? "ACK" : \
(x) == CONFNAK ? "NAK" : "REJ")
/*
* ipcp_init - Initialize IPCP.
*/
static void
ipcp_init(int unit)
{
fsm *f = &ipcp_fsm[unit];
ipcp_options *wo = &ipcp_wantoptions[unit];
ipcp_options *ao = &ipcp_allowoptions[unit];
f->unit = unit;
f->protocol = PPP_IPCP;
f->callbacks = &ipcp_callbacks;
fsm_init(&ipcp_fsm[unit]);
memset(wo, 0, sizeof(*wo));
memset(ao, 0, sizeof(*ao));
wo->neg_addr = 1;
wo->ouraddr = 0;
#if VJ_SUPPORT
wo->neg_vj = 1;
#else /* VJ_SUPPORT */
wo->neg_vj = 0;
#endif /* VJ_SUPPORT */
wo->vj_protocol = IPCP_VJ_COMP;
wo->maxslotindex = MAX_SLOTS - 1;
wo->cflag = 0;
wo->default_route = 1;
ao->neg_addr = 1;
#if VJ_SUPPORT
ao->neg_vj = 1;
#else /* VJ_SUPPORT */
ao->neg_vj = 0;
#endif /* VJ_SUPPORT */
ao->maxslotindex = MAX_SLOTS - 1;
ao->cflag = 1;
ao->default_route = 1;
}
/*
* ipcp_open - IPCP is allowed to come up.
*/
static void
ipcp_open(int unit)
{
fsm_open(&ipcp_fsm[unit]);
}
/*
* ipcp_close - Take IPCP down.
*/
static void
ipcp_close(int unit, char *reason)
{
fsm_close(&ipcp_fsm[unit], reason);
}
/*
* ipcp_lowerup - The lower layer is up.
*/
static void
ipcp_lowerup(int unit)
{
fsm_lowerup(&ipcp_fsm[unit]);
}
/*
* ipcp_lowerdown - The lower layer is down.
*/
static void
ipcp_lowerdown(int unit)
{
fsm_lowerdown(&ipcp_fsm[unit]);
}
/*
* ipcp_input - Input IPCP packet.
*/
static void
ipcp_input(int unit, u_char *p, int len)
{
fsm_input(&ipcp_fsm[unit], p, len);
}
/*
* ipcp_protrej - A Protocol-Reject was received for IPCP.
*
* Pretend the lower layer went down, so we shut up.
*/
static void
ipcp_protrej(int unit)
{
fsm_lowerdown(&ipcp_fsm[unit]);
}
/*
* ipcp_resetci - Reset our CI.
*/
static void
ipcp_resetci(fsm *f)
{
ipcp_options *wo = &ipcp_wantoptions[f->unit];
wo->req_addr = wo->neg_addr && ipcp_allowoptions[f->unit].neg_addr;
if (wo->ouraddr == 0) {
wo->accept_local = 1;
}
if (wo->hisaddr == 0) {
wo->accept_remote = 1;
}
/* Request DNS addresses from the peer */
wo->req_dns1 = ppp_settings.usepeerdns;
wo->req_dns2 = ppp_settings.usepeerdns;
ipcp_gotoptions[f->unit] = *wo;
cis_received[f->unit] = 0;
}
/*
* ipcp_cilen - Return length of our CI.
*/
static int
ipcp_cilen(fsm *f)
{
ipcp_options *go = &ipcp_gotoptions[f->unit];
ipcp_options *wo = &ipcp_wantoptions[f->unit];
ipcp_options *ho = &ipcp_hisoptions[f->unit];
#define LENCIVJ(neg, old) (neg ? (old? CILEN_COMPRESS : CILEN_VJ) : 0)
#define LENCIADDR(neg, old) (neg ? (old? CILEN_ADDRS : CILEN_ADDR) : 0)
#define LENCIDNS(neg) (neg ? (CILEN_ADDR) : 0)
/*
* First see if we want to change our options to the old
* forms because we have received old forms from the peer.
*/
if (wo->neg_addr && !go->neg_addr && !go->old_addrs) {
/* use the old style of address negotiation */
go->neg_addr = 1;
go->old_addrs = 1;
}
if (wo->neg_vj && !go->neg_vj && !go->old_vj) {
/* try an older style of VJ negotiation */
if (cis_received[f->unit] == 0) {
/* keep trying the new style until we see some CI from the peer */
go->neg_vj = 1;
} else {
/* use the old style only if the peer did */
if (ho->neg_vj && ho->old_vj) {
go->neg_vj = 1;
go->old_vj = 1;
go->vj_protocol = ho->vj_protocol;
}
}
}
return (LENCIADDR(go->neg_addr, go->old_addrs) +
LENCIVJ(go->neg_vj, go->old_vj) +
LENCIDNS(go->req_dns1) +
LENCIDNS(go->req_dns2));
}
/*
* ipcp_addci - Add our desired CIs to a packet.
*/
static void
ipcp_addci(fsm *f, u_char *ucp, int *lenp)
{
ipcp_options *go = &ipcp_gotoptions[f->unit];
int len = *lenp;
#define ADDCIVJ(opt, neg, val, old, maxslotindex, cflag) \
if (neg) { \
int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
if (len >= vjlen) { \
PUTCHAR(opt, ucp); \
PUTCHAR(vjlen, ucp); \
PUTSHORT(val, ucp); \
if (!old) { \
PUTCHAR(maxslotindex, ucp); \
PUTCHAR(cflag, ucp); \
} \
len -= vjlen; \
} else { \
neg = 0; \
} \
}
#define ADDCIADDR(opt, neg, old, val1, val2) \
if (neg) { \
int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \
if (len >= addrlen) { \
u32_t l; \
PUTCHAR(opt, ucp); \
PUTCHAR(addrlen, ucp); \
l = ntohl(val1); \
PUTLONG(l, ucp); \
if (old) { \
l = ntohl(val2); \
PUTLONG(l, ucp); \
} \
len -= addrlen; \
} else { \
neg = 0; \
} \
}
#define ADDCIDNS(opt, neg, addr) \
if (neg) { \
if (len >= CILEN_ADDR) { \
u32_t l; \
PUTCHAR(opt, ucp); \
PUTCHAR(CILEN_ADDR, ucp); \
l = ntohl(addr); \
PUTLONG(l, ucp); \
len -= CILEN_ADDR; \
} else { \
neg = 0; \
} \
}
ADDCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr,
go->old_addrs, go->ouraddr, go->hisaddr);
ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
go->maxslotindex, go->cflag);
ADDCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
ADDCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
*lenp -= len;
}
/*
* ipcp_ackci - Ack our CIs.
*
* Returns:
* 0 - Ack was bad.
* 1 - Ack was good.
*/
static int
ipcp_ackci(fsm *f, u_char *p, int len)
{
ipcp_options *go = &ipcp_gotoptions[f->unit];
u_short cilen, citype, cishort;
u32_t cilong;
u_char cimaxslotindex, cicflag;
/*
* CIs must be in exactly the same order that we sent...
* Check packet length and CI length at each step.
* If we find any deviations, then this packet is bad.
*/
#define ACKCIVJ(opt, neg, val, old, maxslotindex, cflag) \
if (neg) { \
int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
if ((len -= vjlen) < 0) { \
goto bad; \
} \
GETCHAR(citype, p); \
GETCHAR(cilen, p); \
if (cilen != vjlen || \
citype != opt) { \
goto bad; \
} \
GETSHORT(cishort, p); \
if (cishort != val) { \
goto bad; \
} \
if (!old) { \
GETCHAR(cimaxslotindex, p); \
if (cimaxslotindex != maxslotindex) { \
goto bad; \
} \
GETCHAR(cicflag, p); \
if (cicflag != cflag) { \
goto bad; \
} \
} \
}
#define ACKCIADDR(opt, neg, old, val1, val2) \
if (neg) { \
int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \
u32_t l; \
if ((len -= addrlen) < 0) { \
goto bad; \
} \
GETCHAR(citype, p); \
GETCHAR(cilen, p); \
if (cilen != addrlen || \
citype != opt) { \
goto bad; \
} \
GETLONG(l, p); \
cilong = htonl(l); \
if (val1 != cilong) { \
goto bad; \
} \
if (old) { \
GETLONG(l, p); \
cilong = htonl(l); \
if (val2 != cilong) { \
goto bad; \
} \
} \
}
#define ACKCIDNS(opt, neg, addr) \
if (neg) { \
u32_t l; \
if ((len -= CILEN_ADDR) < 0) { \
goto bad; \
} \
GETCHAR(citype, p); \
GETCHAR(cilen, p); \
if (cilen != CILEN_ADDR || \
citype != opt) { \
goto bad; \
} \
GETLONG(l, p); \
cilong = htonl(l); \
if (addr != cilong) { \
goto bad; \
} \
}
ACKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr,
go->old_addrs, go->ouraddr, go->hisaddr);
ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
go->maxslotindex, go->cflag);
ACKCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
ACKCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
/*
* If there are any remaining CIs, then this packet is bad.
*/
if (len != 0) {
goto bad;
}
return (1);
bad:
IPCPDEBUG(LOG_INFO, ("ipcp_ackci: received bad Ack!\n"));
return (0);
}
/*
* ipcp_nakci - Peer has sent a NAK for some of our CIs.
* This should not modify any state if the Nak is bad
* or if IPCP is in the LS_OPENED state.
*
* Returns:
* 0 - Nak was bad.
* 1 - Nak was good.
*/
static int
ipcp_nakci(fsm *f, u_char *p, int len)
{
ipcp_options *go = &ipcp_gotoptions[f->unit];
u_char cimaxslotindex, cicflag;
u_char citype, cilen, *next;
u_short cishort;
u32_t ciaddr1, ciaddr2, l, cidnsaddr;
ipcp_options no; /* options we've seen Naks for */
ipcp_options try; /* options to request next time */
BZERO(&no, sizeof(no));
try = *go;
/*
* Any Nak'd CIs must be in exactly the same order that we sent.
* Check packet length and CI length at each step.
* If we find any deviations, then this packet is bad.
*/
#define NAKCIADDR(opt, neg, old, code) \
if (go->neg && \
len >= (cilen = (old? CILEN_ADDRS: CILEN_ADDR)) && \
p[1] == cilen && \
p[0] == opt) { \
len -= cilen; \
INCPTR(2, p); \
GETLONG(l, p); \
ciaddr1 = htonl(l); \
if (old) { \
GETLONG(l, p); \
ciaddr2 = htonl(l); \
no.old_addrs = 1; \
} else { \
ciaddr2 = 0; \
} \
no.neg = 1; \
code \
}
#define NAKCIVJ(opt, neg, code) \
if (go->neg && \
((cilen = p[1]) == CILEN_COMPRESS || cilen == CILEN_VJ) && \
len >= cilen && \
p[0] == opt) { \
len -= cilen; \
INCPTR(2, p); \
GETSHORT(cishort, p); \
no.neg = 1; \
code \
}
#define NAKCIDNS(opt, neg, code) \
if (go->neg && \
((cilen = p[1]) == CILEN_ADDR) && \
len >= cilen && \
p[0] == opt) { \
len -= cilen; \
INCPTR(2, p); \
GETLONG(l, p); \
cidnsaddr = htonl(l); \
no.neg = 1; \
code \
}
/*
* Accept the peer's idea of {our,his} address, if different
* from our idea, only if the accept_{local,remote} flag is set.
*/
NAKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr, go->old_addrs,
if (go->accept_local && ciaddr1) { /* Do we know our address? */
try.ouraddr = ciaddr1;
IPCPDEBUG(LOG_INFO, ("local IP address %s\n",
inet_ntoa(ciaddr1)));
}
if (go->accept_remote && ciaddr2) { /* Does he know his? */
try.hisaddr = ciaddr2;
IPCPDEBUG(LOG_INFO, ("remote IP address %s\n",
inet_ntoa(ciaddr2)));
}
);
/*
* Accept the peer's value of maxslotindex provided that it
* is less than what we asked for. Turn off slot-ID compression
* if the peer wants. Send old-style compress-type option if
* the peer wants.
*/
NAKCIVJ(CI_COMPRESSTYPE, neg_vj,
if (cilen == CILEN_VJ) {
GETCHAR(cimaxslotindex, p);
GETCHAR(cicflag, p);
if (cishort == IPCP_VJ_COMP) {
try.old_vj = 0;
if (cimaxslotindex < go->maxslotindex) {
try.maxslotindex = cimaxslotindex;
}
if (!cicflag) {
try.cflag = 0;
}
} else {
try.neg_vj = 0;
}
} else {
if (cishort == IPCP_VJ_COMP || cishort == IPCP_VJ_COMP_OLD) {
try.old_vj = 1;
try.vj_protocol = cishort;
} else {
try.neg_vj = 0;
}
}
);
NAKCIDNS(CI_MS_DNS1, req_dns1,
try.dnsaddr[0] = cidnsaddr;
IPCPDEBUG(LOG_INFO, ("primary DNS address %s\n", inet_ntoa(cidnsaddr)));
);
NAKCIDNS(CI_MS_DNS2, req_dns2,
try.dnsaddr[1] = cidnsaddr;
IPCPDEBUG(LOG_INFO, ("secondary DNS address %s\n", inet_ntoa(cidnsaddr)));
);
/*
* There may be remaining CIs, if the peer is requesting negotiation
* on an option that we didn't include in our request packet.
* If they want to negotiate about IP addresses, we comply.
* If they want us to ask for compression, we refuse.
*/
while (len > CILEN_VOID) {
GETCHAR(citype, p);
GETCHAR(cilen, p);
if( (len -= cilen) < 0 ) {
goto bad;
}
next = p + cilen - 2;
switch (citype) {
case CI_COMPRESSTYPE:
if (go->neg_vj || no.neg_vj ||
(cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) {
goto bad;
}
no.neg_vj = 1;
break;
case CI_ADDRS:
if ((go->neg_addr && go->old_addrs) || no.old_addrs
|| cilen != CILEN_ADDRS) {
goto bad;
}
try.neg_addr = 1;
try.old_addrs = 1;
GETLONG(l, p);
ciaddr1 = htonl(l);
if (ciaddr1 && go->accept_local) {
try.ouraddr = ciaddr1;
}
GETLONG(l, p);
ciaddr2 = htonl(l);
if (ciaddr2 && go->accept_remote) {
try.hisaddr = ciaddr2;
}
no.old_addrs = 1;
break;
case CI_ADDR:
if (go->neg_addr || no.neg_addr || cilen != CILEN_ADDR) {
goto bad;
}
try.old_addrs = 0;
GETLONG(l, p);
ciaddr1 = htonl(l);
if (ciaddr1 && go->accept_local) {
try.ouraddr = ciaddr1;
}
if (try.ouraddr != 0) {
try.neg_addr = 1;
}
no.neg_addr = 1;
break;
}
p = next;
}
/* If there is still anything left, this packet is bad. */
if (len != 0) {
goto bad;
}
/*
* OK, the Nak is good. Now we can update state.
*/
if (f->state != LS_OPENED) {
*go = try;
}
return 1;
bad:
IPCPDEBUG(LOG_INFO, ("ipcp_nakci: received bad Nak!\n"));
return 0;
}
/*
* ipcp_rejci - Reject some of our CIs.
*/
static int
ipcp_rejci(fsm *f, u_char *p, int len)
{
ipcp_options *go = &ipcp_gotoptions[f->unit];
u_char cimaxslotindex, ciflag, cilen;
u_short cishort;
u32_t cilong;
ipcp_options try; /* options to request next time */
try = *go;
/*
* Any Rejected CIs must be in exactly the same order that we sent.
* Check packet length and CI length at each step.
* If we find any deviations, then this packet is bad.
*/
#define REJCIADDR(opt, neg, old, val1, val2) \
if (go->neg && \
len >= (cilen = old? CILEN_ADDRS: CILEN_ADDR) && \
p[1] == cilen && \
p[0] == opt) { \
u32_t l; \
len -= cilen; \
INCPTR(2, p); \
GETLONG(l, p); \
cilong = htonl(l); \
/* Check rejected value. */ \
if (cilong != val1) { \
goto bad; \
} \
if (old) { \
GETLONG(l, p); \
cilong = htonl(l); \
/* Check rejected value. */ \
if (cilong != val2) { \
goto bad; \
} \
} \
try.neg = 0; \
}
#define REJCIVJ(opt, neg, val, old, maxslot, cflag) \
if (go->neg && \
p[1] == (old? CILEN_COMPRESS : CILEN_VJ) && \
len >= p[1] && \
p[0] == opt) { \
len -= p[1]; \
INCPTR(2, p); \
GETSHORT(cishort, p); \
/* Check rejected value. */ \
if (cishort != val) { \
goto bad; \
} \
if (!old) { \
GETCHAR(cimaxslotindex, p); \
if (cimaxslotindex != maxslot) { \
goto bad; \
} \
GETCHAR(ciflag, p); \
if (ciflag != cflag) { \
goto bad; \
} \
} \
try.neg = 0; \
}
#define REJCIDNS(opt, neg, dnsaddr) \
if (go->neg && \
((cilen = p[1]) == CILEN_ADDR) && \
len >= cilen && \
p[0] == opt) { \
u32_t l; \
len -= cilen; \
INCPTR(2, p); \
GETLONG(l, p); \
cilong = htonl(l); \
/* Check rejected value. */ \
if (cilong != dnsaddr) { \
goto bad; \
} \
try.neg = 0; \
}
REJCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr,
go->old_addrs, go->ouraddr, go->hisaddr);
REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol, go->old_vj,
go->maxslotindex, go->cflag);
REJCIDNS(CI_MS_DNS1, req_dns1, go->dnsaddr[0]);
REJCIDNS(CI_MS_DNS2, req_dns2, go->dnsaddr[1]);
/*
* If there are any remaining CIs, then this packet is bad.
*/
if (len != 0) {
goto bad;
}
/*
* Now we can update state.
*/
if (f->state != LS_OPENED) {
*go = try;
}
return 1;
bad:
IPCPDEBUG(LOG_INFO, ("ipcp_rejci: received bad Reject!\n"));
return 0;
}
/*
* ipcp_reqci - Check the peer's requested CIs and send appropriate response.
*
* Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
* appropriately. If reject_if_disagree is non-zero, doesn't return
* CONFNAK; returns CONFREJ if it can't return CONFACK.
*/
static int
ipcp_reqci(fsm *f, u_char *inp/* Requested CIs */,int *len/* Length of requested CIs */,int reject_if_disagree)
{
ipcp_options *wo = &ipcp_wantoptions[f->unit];
ipcp_options *ho = &ipcp_hisoptions[f->unit];
ipcp_options *ao = &ipcp_allowoptions[f->unit];
#ifdef OLD_CI_ADDRS
ipcp_options *go = &ipcp_gotoptions[f->unit];
#endif
u_char *cip, *next; /* Pointer to current and next CIs */
u_short cilen, citype; /* Parsed len, type */
u_short cishort; /* Parsed short value */
u32_t tl, ciaddr1; /* Parsed address values */
#ifdef OLD_CI_ADDRS
u32_t ciaddr2; /* Parsed address values */
#endif
int rc = CONFACK; /* Final packet return code */
int orc; /* Individual option return code */
u_char *p; /* Pointer to next char to parse */
u_char *ucp = inp; /* Pointer to current output char */
int l = *len; /* Length left */
u_char maxslotindex, cflag;
int d;
cis_received[f->unit] = 1;
/*
* Reset all his options.
*/
BZERO(ho, sizeof(*ho));
/*
* Process all his options.
*/
next = inp;
while (l) {
orc = CONFACK; /* Assume success */
cip = p = next; /* Remember begining of CI */
if (l < 2 || /* Not enough data for CI header or */
p[1] < 2 || /* CI length too small or */
p[1] > l) { /* CI length too big? */
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: bad CI length!\n"));
orc = CONFREJ; /* Reject bad CI */
cilen = (u_short)l;/* Reject till end of packet */
l = 0; /* Don't loop again */
goto endswitch;
}
GETCHAR(citype, p); /* Parse CI type */
GETCHAR(cilen, p); /* Parse CI length */
l -= cilen; /* Adjust remaining length */
next += cilen; /* Step to next CI */
switch (citype) { /* Check CI type */
#ifdef OLD_CI_ADDRS /* Need to save space... */
case CI_ADDRS:
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received ADDRS\n"));
if (!ao->neg_addr ||
cilen != CILEN_ADDRS) { /* Check CI length */
orc = CONFREJ; /* Reject CI */
break;
}
/*
* If he has no address, or if we both have his address but
* disagree about it, then NAK it with our idea.
* In particular, if we don't know his address, but he does,
* then accept it.
*/
GETLONG(tl, p); /* Parse source address (his) */
ciaddr1 = htonl(tl);
IPCPDEBUG(LOG_INFO, ("his addr %s\n", inet_ntoa(ciaddr1)));
if (ciaddr1 != wo->hisaddr
&& (ciaddr1 == 0 || !wo->accept_remote)) {
orc = CONFNAK;
if (!reject_if_disagree) {
DECPTR(sizeof(u32_t), p);
tl = ntohl(wo->hisaddr);
PUTLONG(tl, p);
}
} else if (ciaddr1 == 0 && wo->hisaddr == 0) {
/*
* If neither we nor he knows his address, reject the option.
*/
orc = CONFREJ;
wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */
break;
}
/*
* If he doesn't know our address, or if we both have our address
* but disagree about it, then NAK it with our idea.
*/
GETLONG(tl, p); /* Parse desination address (ours) */
ciaddr2 = htonl(tl);
IPCPDEBUG(LOG_INFO, ("our addr %s\n", inet_ntoa(ciaddr2)));
if (ciaddr2 != wo->ouraddr) {
if (ciaddr2 == 0 || !wo->accept_local) {
orc = CONFNAK;
if (!reject_if_disagree) {
DECPTR(sizeof(u32_t), p);
tl = ntohl(wo->ouraddr);
PUTLONG(tl, p);
}
} else {
go->ouraddr = ciaddr2; /* accept peer's idea */
}
}
ho->neg_addr = 1;
ho->old_addrs = 1;
ho->hisaddr = ciaddr1;
ho->ouraddr = ciaddr2;
break;
#endif
case CI_ADDR:
if (!ao->neg_addr) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR not allowed\n"));
orc = CONFREJ; /* Reject CI */
break;
} else if (cilen != CILEN_ADDR) { /* Check CI length */
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR bad len\n"));
orc = CONFREJ; /* Reject CI */
break;
}
/*
* If he has no address, or if we both have his address but
* disagree about it, then NAK it with our idea.
* In particular, if we don't know his address, but he does,
* then accept it.
*/
GETLONG(tl, p); /* Parse source address (his) */
ciaddr1 = htonl(tl);
if (ciaddr1 != wo->hisaddr
&& (ciaddr1 == 0 || !wo->accept_remote)) {
orc = CONFNAK;
if (!reject_if_disagree) {
DECPTR(sizeof(u32_t), p);
tl = ntohl(wo->hisaddr);
PUTLONG(tl, p);
}
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Nak ADDR %s\n", inet_ntoa(ciaddr1)));
} else if (ciaddr1 == 0 && wo->hisaddr == 0) {
/*
* Don't ACK an address of 0.0.0.0 - reject it instead.
*/
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR %s\n", inet_ntoa(ciaddr1)));
orc = CONFREJ;
wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */
break;
}
ho->neg_addr = 1;
ho->hisaddr = ciaddr1;
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: ADDR %s\n", inet_ntoa(ciaddr1)));
break;
case CI_MS_DNS1:
case CI_MS_DNS2:
/* Microsoft primary or secondary DNS request */
d = citype == CI_MS_DNS2;
/* If we do not have a DNS address then we cannot send it */
if (ao->dnsaddr[d] == 0 ||
cilen != CILEN_ADDR) { /* Check CI length */
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting DNS%d Request\n", d+1));
orc = CONFREJ; /* Reject CI */
break;
}
GETLONG(tl, p);
if (htonl(tl) != ao->dnsaddr[d]) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking DNS%d Request %s\n",
d+1, inet_ntoa(tl)));
DECPTR(sizeof(u32_t), p);
tl = ntohl(ao->dnsaddr[d]);
PUTLONG(tl, p);
orc = CONFNAK;
}
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received DNS%d Request\n", d+1));
break;
case CI_MS_WINS1:
case CI_MS_WINS2:
/* Microsoft primary or secondary WINS request */
d = citype == CI_MS_WINS2;
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received WINS%d Request\n", d+1));
/* If we do not have a DNS address then we cannot send it */
if (ao->winsaddr[d] == 0 ||
cilen != CILEN_ADDR) { /* Check CI length */
orc = CONFREJ; /* Reject CI */
break;
}
GETLONG(tl, p);
if (htonl(tl) != ao->winsaddr[d]) {
DECPTR(sizeof(u32_t), p);
tl = ntohl(ao->winsaddr[d]);
PUTLONG(tl, p);
orc = CONFNAK;
}
break;
case CI_COMPRESSTYPE:
if (!ao->neg_vj) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE not allowed\n"));
orc = CONFREJ;
break;
} else if (cilen != CILEN_VJ && cilen != CILEN_COMPRESS) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE len=%d\n", cilen));
orc = CONFREJ;
break;
}
GETSHORT(cishort, p);
if (!(cishort == IPCP_VJ_COMP ||
(cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE %d\n", cishort));
orc = CONFREJ;
break;
}
ho->neg_vj = 1;
ho->vj_protocol = cishort;
if (cilen == CILEN_VJ) {
GETCHAR(maxslotindex, p);
if (maxslotindex > ao->maxslotindex) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking VJ max slot %d\n", maxslotindex));
orc = CONFNAK;
if (!reject_if_disagree) {
DECPTR(1, p);
PUTCHAR(ao->maxslotindex, p);
}
}
GETCHAR(cflag, p);
if (cflag && !ao->cflag) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking VJ cflag %d\n", cflag));
orc = CONFNAK;
if (!reject_if_disagree) {
DECPTR(1, p);
PUTCHAR(wo->cflag, p);
}
}
ho->maxslotindex = maxslotindex;
ho->cflag = cflag;
} else {
ho->old_vj = 1;
ho->maxslotindex = MAX_SLOTS - 1;
ho->cflag = 1;
}
IPCPDEBUG(LOG_INFO, (
"ipcp_reqci: received COMPRESSTYPE p=%d old=%d maxslot=%d cflag=%d\n",
ho->vj_protocol, ho->old_vj, ho->maxslotindex, ho->cflag));
break;
default:
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting unknown CI type %d\n", citype));
orc = CONFREJ;
break;
}
endswitch:
if (orc == CONFACK && /* Good CI */
rc != CONFACK) { /* but prior CI wasnt? */
continue; /* Don't send this one */
}
if (orc == CONFNAK) { /* Nak this CI? */
if (reject_if_disagree) { /* Getting fed up with sending NAKs? */
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting too many naks\n"));
orc = CONFREJ; /* Get tough if so */
} else {
if (rc == CONFREJ) { /* Rejecting prior CI? */
continue; /* Don't send this one */
}
if (rc == CONFACK) { /* Ack'd all prior CIs? */
rc = CONFNAK; /* Not anymore... */
ucp = inp; /* Backup */
}
}
}
if (orc == CONFREJ && /* Reject this CI */
rc != CONFREJ) { /* but no prior ones? */
rc = CONFREJ;
ucp = inp; /* Backup */
}
/* Need to move CI? */
if (ucp != cip) {
BCOPY(cip, ucp, cilen); /* Move it */
}
/* Update output pointer */
INCPTR(cilen, ucp);
}
/*
* If we aren't rejecting this packet, and we want to negotiate
* their address, and they didn't send their address, then we
* send a NAK with a CI_ADDR option appended. We assume the
* input buffer is long enough that we can append the extra
* option safely.
*/
if (rc != CONFREJ && !ho->neg_addr &&
wo->req_addr && !reject_if_disagree) {
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Requesting peer address\n"));
if (rc == CONFACK) {
rc = CONFNAK;
ucp = inp; /* reset pointer */
wo->req_addr = 0; /* don't ask again */
}
PUTCHAR(CI_ADDR, ucp);
PUTCHAR(CILEN_ADDR, ucp);
tl = ntohl(wo->hisaddr);
PUTLONG(tl, ucp);
}
*len = (int)(ucp - inp); /* Compute output length */
IPCPDEBUG(LOG_INFO, ("ipcp_reqci: returning Configure-%s\n", CODENAME(rc)));
return (rc); /* Return final code */
}
#if 0
/*
* ip_check_options - check that any IP-related options are OK,
* and assign appropriate defaults.
*/
static void
ip_check_options(u_long localAddr)
{
ipcp_options *wo = &ipcp_wantoptions[0];
/*
* Load our default IP address but allow the remote host to give us
* a new address.
*/
if (wo->ouraddr == 0 && !ppp_settings.disable_defaultip) {
wo->accept_local = 1; /* don't insist on this default value */
wo->ouraddr = htonl(localAddr);
}
}
#endif
/*
* ipcp_up - IPCP has come UP.
*
* Configure the IP network interface appropriately and bring it up.
*/
static void
ipcp_up(fsm *f)
{
u32_t mask;
ipcp_options *ho = &ipcp_hisoptions[f->unit];
ipcp_options *go = &ipcp_gotoptions[f->unit];
ipcp_options *wo = &ipcp_wantoptions[f->unit];
np_up(f->unit, PPP_IP);
IPCPDEBUG(LOG_INFO, ("ipcp: up\n"));
/*
* We must have a non-zero IP address for both ends of the link.
*/
if (!ho->neg_addr) {
ho->hisaddr = wo->hisaddr;
}
if (ho->hisaddr == 0) {
IPCPDEBUG(LOG_ERR, ("Could not determine remote IP address\n"));
ipcp_close(f->unit, "Could not determine remote IP address");
return;
}
if (go->ouraddr == 0) {
IPCPDEBUG(LOG_ERR, ("Could not determine local IP address\n"));
ipcp_close(f->unit, "Could not determine local IP address");
return;
}
if (ppp_settings.usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) {
/*pppGotDNSAddrs(go->dnsaddr[0], go->dnsaddr[1]);*/
}
/*
* Check that the peer is allowed to use the IP address it wants.
*/
if (!auth_ip_addr(f->unit, ho->hisaddr)) {
IPCPDEBUG(LOG_ERR, ("Peer is not authorized to use remote address %s\n",
inet_ntoa(ho->hisaddr)));
ipcp_close(f->unit, "Unauthorized remote IP address");
return;
}
/* set tcp compression */
sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex);
/*
* Set IP addresses and (if specified) netmask.
*/
mask = GetMask(go->ouraddr);
if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask, go->dnsaddr[0], go->dnsaddr[1])) {
IPCPDEBUG(LOG_WARNING, ("sifaddr failed\n"));
ipcp_close(f->unit, "Interface configuration failed");
return;
}
/* bring the interface up for IP */
if (!sifup(f->unit)) {
IPCPDEBUG(LOG_WARNING, ("sifup failed\n"));
ipcp_close(f->unit, "Interface configuration failed");
return;
}
sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
/* assign a default route through the interface if required */
if (ipcp_wantoptions[f->unit].default_route) {
if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr)) {
default_route_set[f->unit] = 1;
}
}
IPCPDEBUG(LOG_NOTICE, ("local IP address %s\n", inet_ntoa(go->ouraddr)));
IPCPDEBUG(LOG_NOTICE, ("remote IP address %s\n", inet_ntoa(ho->hisaddr)));
if (go->dnsaddr[0]) {
IPCPDEBUG(LOG_NOTICE, ("primary DNS address %s\n", inet_ntoa(go->dnsaddr[0])));
}
if (go->dnsaddr[1]) {
IPCPDEBUG(LOG_NOTICE, ("secondary DNS address %s\n", inet_ntoa(go->dnsaddr[1])));
}
}
/*
* ipcp_down - IPCP has gone DOWN.
*
* Take the IP network interface down, clear its addresses
* and delete routes through it.
*/
static void
ipcp_down(fsm *f)
{
IPCPDEBUG(LOG_INFO, ("ipcp: down\n"));
np_down(f->unit, PPP_IP);
sifvjcomp(f->unit, 0, 0, 0);
sifdown(f->unit);
ipcp_clear_addrs(f->unit);
}
/*
* ipcp_clear_addrs() - clear the interface addresses, routes, etc.
*/
static void
ipcp_clear_addrs(int unit)
{
u32_t ouraddr, hisaddr;
ouraddr = ipcp_gotoptions[unit].ouraddr;
hisaddr = ipcp_hisoptions[unit].hisaddr;
if (default_route_set[unit]) {
cifdefaultroute(unit, ouraddr, hisaddr);
default_route_set[unit] = 0;
}
cifaddr(unit, ouraddr, hisaddr);
}
/*
* ipcp_finished - possibly shut down the lower layers.
*/
static void
ipcp_finished(fsm *f)
{
np_finished(f->unit, PPP_IP);
}
#if PPP_ADDITIONAL_CALLBACKS
static int
ipcp_printpkt(u_char *p, int plen, void (*printer) (void *, char *, ...), void *arg)
{
LWIP_UNUSED_ARG(p);
LWIP_UNUSED_ARG(plen);
LWIP_UNUSED_ARG(printer);
LWIP_UNUSED_ARG(arg);
return 0;
}
/*
* ip_active_pkt - see if this IP packet is worth bringing the link up for.
* We don't bring the link up for IP fragments or for TCP FIN packets
* with no data.
*/
#define IP_HDRLEN 20 /* bytes */
#define IP_OFFMASK 0x1fff
#define IPPROTO_TCP 6
#define TCP_HDRLEN 20
#define TH_FIN 0x01
/*
* We use these macros because the IP header may be at an odd address,
* and some compilers might use word loads to get th_off or ip_hl.
*/
#define net_short(x) (((x)[0] << 8) + (x)[1])
#define get_iphl(x) (((unsigned char *)(x))[0] & 0xF)
#define get_ipoff(x) net_short((unsigned char *)(x) + 6)
#define get_ipproto(x) (((unsigned char *)(x))[9])
#define get_tcpoff(x) (((unsigned char *)(x))[12] >> 4)
#define get_tcpflags(x) (((unsigned char *)(x))[13])
static int
ip_active_pkt(u_char *pkt, int len)
{
u_char *tcp;
int hlen;
len -= PPP_HDRLEN;
pkt += PPP_HDRLEN;
if (len < IP_HDRLEN) {
return 0;
}
if ((get_ipoff(pkt) & IP_OFFMASK) != 0) {
return 0;
}
if (get_ipproto(pkt) != IPPROTO_TCP) {
return 1;
}
hlen = get_iphl(pkt) * 4;
if (len < hlen + TCP_HDRLEN) {
return 0;
}
tcp = pkt + hlen;
if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == hlen + get_tcpoff(tcp) * 4) {
return 0;
}
return 1;
}
#endif /* PPP_ADDITIONAL_CALLBACKS */
#endif /* PPP_SUPPORT */
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