3285bb3c97
Instead, use the correct values based on the number of bits actually negotiated. Spotted by: Sergey Korolew <ds@rt.balakovo.ru>
815 lines
20 KiB
C
815 lines
20 KiB
C
/*-
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* Copyright (c) 2000 Semen Ustimenko <semenu@FreeBSD.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/socket.h>
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#include <netinet/in_systm.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <sys/un.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <termios.h>
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#include <openssl/rc4.h>
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#include "defs.h"
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#include "mbuf.h"
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#include "log.h"
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#include "timer.h"
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#include "fsm.h"
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#include "lqr.h"
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#include "hdlc.h"
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#include "lcp.h"
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#include "ccp.h"
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#include "throughput.h"
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#include "layer.h"
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#include "link.h"
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#include "chap_ms.h"
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#include "proto.h"
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#include "mppe.h"
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#include "ua.h"
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#include "descriptor.h"
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#ifndef NORADIUS
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#include "radius.h"
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#endif
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#include "ncpaddr.h"
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#include "iplist.h"
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#include "slcompress.h"
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#include "ipcp.h"
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#include "ipv6cp.h"
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#include "filter.h"
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#include "mp.h"
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#include "ncp.h"
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#include "bundle.h"
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/*
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* Documentation:
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*
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* draft-ietf-pppext-mppe-04.txt
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* draft-ietf-pppext-mppe-keys-02.txt
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*/
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#define MPPE_OPT_STATELESS 0x1000000
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#define MPPE_OPT_COMPRESSED 0x01
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#define MPPE_OPT_40BIT 0x20
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#define MPPE_OPT_56BIT 0x80
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#define MPPE_OPT_128BIT 0x40
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#define MPPE_OPT_BITMASK 0xe0
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#define MPPE_OPT_MASK (MPPE_OPT_STATELESS | MPPE_OPT_BITMASK)
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#define MPPE_FLUSHED 0x8000
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#define MPPE_ENCRYPTED 0x1000
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#define MPPE_HEADER_BITMASK 0xf000
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#define MPPE_HEADER_FLAG 0x00ff
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#define MPPE_HEADER_FLAGMASK 0x00ff
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#define MPPE_HEADER_FLAGSHIFT 8
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#define MPPE_HEADER_STATEFUL_KEYCHANGES 16
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struct mppe_state {
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unsigned stateless : 1;
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unsigned flushnext : 1;
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unsigned flushrequired : 1;
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int cohnum;
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int keylen; /* 8 or 16 bytes */
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int keybits; /* 40, 56 or 128 bits */
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char sesskey[MPPE_KEY_LEN];
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char mastkey[MPPE_KEY_LEN];
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RC4_KEY rc4key;
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};
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int MPPE_MasterKeyValid = 0;
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int MPPE_IsServer = 0;
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char MPPE_MasterKey[MPPE_KEY_LEN];
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/*
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* The peer has missed a packet. Mark the next output frame to be FLUSHED
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*/
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static int
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MPPEResetOutput(void *v)
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{
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struct mppe_state *mop = (struct mppe_state *)v;
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if (mop->stateless)
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log_Printf(LogCCP, "MPPE: Unexpected output channel reset\n");
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else {
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log_Printf(LogCCP, "MPPE: Output channel reset\n");
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mop->flushnext = 1;
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}
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return 0; /* Ask FSM not to ACK */
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}
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static void
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MPPEReduceSessionKey(struct mppe_state *mp)
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{
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switch(mp->keybits) {
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case 40:
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mp->sesskey[2] = 0x9e;
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mp->sesskey[1] = 0x26;
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case 56:
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mp->sesskey[0] = 0xd1;
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case 128:
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break;
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}
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}
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static void
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MPPEKeyChange(struct mppe_state *mp)
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{
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char InterimKey[MPPE_KEY_LEN];
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RC4_KEY RC4Key;
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GetNewKeyFromSHA(mp->mastkey, mp->sesskey, mp->keylen, InterimKey);
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RC4_set_key(&RC4Key, mp->keylen, InterimKey);
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RC4(&RC4Key, mp->keylen, InterimKey, mp->sesskey);
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MPPEReduceSessionKey(mp);
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}
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static struct mbuf *
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MPPEOutput(void *v, struct ccp *ccp, struct link *l, int pri, u_short *proto,
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struct mbuf *mp)
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{
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struct mppe_state *mop = (struct mppe_state *)v;
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struct mbuf *mo;
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u_short nproto, prefix;
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int dictinit, ilen, len;
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char *rp;
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ilen = m_length(mp);
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dictinit = 0;
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log_Printf(LogDEBUG, "MPPE: Output: Proto %02x (%d bytes)\n", *proto, ilen);
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if (*proto < 0x21 && *proto > 0xFA) {
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log_Printf(LogDEBUG, "MPPE: Output: Not encrypting\n");
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ccp->compout += ilen;
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ccp->uncompout += ilen;
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return mp;
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}
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log_DumpBp(LogDEBUG, "MPPE: Output: Encrypt packet:", mp);
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/* Get mbuf for prefixes */
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mo = m_get(4, MB_CCPOUT);
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mo->m_next = mp;
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rp = MBUF_CTOP(mo);
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prefix = MPPE_ENCRYPTED | mop->cohnum;
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if (mop->stateless ||
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(mop->cohnum & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG) {
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/* Change our key */
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log_Printf(LogDEBUG, "MPPEOutput: Key changed [%d]\n", mop->cohnum);
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MPPEKeyChange(mop);
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dictinit = 1;
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}
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if (mop->stateless || mop->flushnext) {
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prefix |= MPPE_FLUSHED;
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dictinit = 1;
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mop->flushnext = 0;
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}
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if (dictinit) {
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/* Initialise our dictionary */
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log_Printf(LogDEBUG, "MPPEOutput: Dictionary initialised [%d]\n",
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mop->cohnum);
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RC4_set_key(&mop->rc4key, mop->keylen, mop->sesskey);
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}
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/* Set MPPE packet prefix */
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ua_htons(&prefix, rp);
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/* Save encrypted protocol number */
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nproto = htons(*proto);
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RC4(&mop->rc4key, 2, (char *)&nproto, rp + 2);
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/* Encrypt main packet */
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rp = MBUF_CTOP(mp);
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RC4(&mop->rc4key, ilen, rp, rp);
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mop->cohnum++;
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mop->cohnum &= ~MPPE_HEADER_BITMASK;
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/* Set the protocol number */
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*proto = ccp_Proto(ccp);
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len = m_length(mo);
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ccp->uncompout += ilen;
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ccp->compout += len;
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log_Printf(LogDEBUG, "MPPE: Output: Encrypted: Proto %02x (%d bytes)\n",
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*proto, len);
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return mo;
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}
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static void
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MPPEResetInput(void *v)
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{
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log_Printf(LogCCP, "MPPE: Unexpected input channel ack\n");
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}
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static struct mbuf *
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MPPEInput(void *v, struct ccp *ccp, u_short *proto, struct mbuf *mp)
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{
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struct mppe_state *mip = (struct mppe_state *)v;
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u_short prefix;
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char *rp;
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int dictinit, flushed, ilen, len, n;
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ilen = m_length(mp);
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dictinit = 0;
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ccp->compin += ilen;
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log_Printf(LogDEBUG, "MPPE: Input: Proto %02x (%d bytes)\n", *proto, ilen);
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log_DumpBp(LogDEBUG, "MPPE: Input: Packet:", mp);
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mp = mbuf_Read(mp, &prefix, 2);
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prefix = ntohs(prefix);
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flushed = prefix & MPPE_FLUSHED;
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prefix &= ~flushed;
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if ((prefix & MPPE_HEADER_BITMASK) != MPPE_ENCRYPTED) {
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log_Printf(LogERROR, "MPPE: Input: Invalid packet (flags = 0x%x)\n",
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(prefix & MPPE_HEADER_BITMASK) | flushed);
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m_freem(mp);
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return NULL;
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}
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prefix &= ~MPPE_HEADER_BITMASK;
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if (!flushed && mip->stateless) {
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log_Printf(LogCCP, "MPPEInput: Packet without MPPE_FLUSHED set"
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" in stateless mode\n");
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flushed = MPPE_FLUSHED;
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/* Should we really continue ? */
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}
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if (mip->stateless) {
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/* Change our key for each missed packet in stateless mode */
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while (prefix != mip->cohnum) {
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log_Printf(LogDEBUG, "MPPEInput: Key changed [%u]\n", prefix);
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MPPEKeyChange(mip);
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/*
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* mip->cohnum contains what we received last time in stateless
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* mode.
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*/
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mip->cohnum++;
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mip->cohnum &= ~MPPE_HEADER_BITMASK;
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}
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dictinit = 1;
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} else {
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if (flushed) {
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/*
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* We can always process a flushed packet.
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* Catch up on any outstanding key changes.
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*/
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n = (prefix >> MPPE_HEADER_FLAGSHIFT) -
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(mip->cohnum >> MPPE_HEADER_FLAGSHIFT);
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if (n < 0)
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n += MPPE_HEADER_STATEFUL_KEYCHANGES;
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while (n--) {
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log_Printf(LogDEBUG, "MPPEInput: Key changed during catchup [%u]\n",
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prefix);
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MPPEKeyChange(mip);
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}
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mip->flushrequired = 0;
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mip->cohnum = prefix;
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dictinit = 1;
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}
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if (mip->flushrequired) {
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/*
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* Perhaps we should be lenient if
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* (prefix & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG
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* The spec says that we shouldn't be though....
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*/
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log_Printf(LogDEBUG, "MPPE: Not flushed - discarded\n");
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fsm_Output(&ccp->fsm, CODE_RESETREQ, ccp->fsm.reqid++, NULL, 0,
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MB_CCPOUT);
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m_freem(mp);
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return NULL;
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}
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if (prefix != mip->cohnum) {
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/*
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* We're in stateful mode and didn't receive the expected
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* packet. Send a reset request, but don't tell the CCP layer
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* about it as we don't expect to receive a Reset ACK !
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* Guess what... M$ invented this !
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*/
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log_Printf(LogCCP, "MPPE: Input: Got seq %u, not %u\n",
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prefix, mip->cohnum);
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fsm_Output(&ccp->fsm, CODE_RESETREQ, ccp->fsm.reqid++, NULL, 0,
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MB_CCPOUT);
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mip->flushrequired = 1;
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m_freem(mp);
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return NULL;
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}
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if ((prefix & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG) {
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log_Printf(LogDEBUG, "MPPEInput: Key changed [%u]\n", prefix);
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MPPEKeyChange(mip);
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dictinit = 1;
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} else if (flushed)
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dictinit = 1;
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/*
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* mip->cohnum contains what we expect to receive next time in stateful
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* mode.
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*/
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mip->cohnum++;
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mip->cohnum &= ~MPPE_HEADER_BITMASK;
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}
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if (dictinit) {
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log_Printf(LogDEBUG, "MPPEInput: Dictionary initialised [%u]\n", prefix);
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RC4_set_key(&mip->rc4key, mip->keylen, mip->sesskey);
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}
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mp = mbuf_Read(mp, proto, 2);
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RC4(&mip->rc4key, 2, (char *)proto, (char *)proto);
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*proto = ntohs(*proto);
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rp = MBUF_CTOP(mp);
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len = m_length(mp);
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RC4(&mip->rc4key, len, rp, rp);
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log_Printf(LogDEBUG, "MPPEInput: Decrypted: Proto %02x (%d bytes)\n",
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*proto, len);
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log_DumpBp(LogDEBUG, "MPPEInput: Decrypted: Packet:", mp);
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ccp->uncompin += len;
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return mp;
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}
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static void
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MPPEDictSetup(void *v, struct ccp *ccp, u_short proto, struct mbuf *mi)
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{
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}
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static const char *
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MPPEDispOpts(struct fsm_opt *o)
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{
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static char buf[70];
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u_int32_t val;
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char ch;
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int len, n;
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ua_ntohl(o->data, &val);
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len = 0;
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if ((n = snprintf(buf, sizeof buf, "value 0x%08x ", (unsigned)val)) > 0)
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len += n;
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if (!(val & MPPE_OPT_BITMASK)) {
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if ((n = snprintf(buf + len, sizeof buf - len, "(0")) > 0)
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len += n;
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} else {
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ch = '(';
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if (val & MPPE_OPT_128BIT) {
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if ((n = snprintf(buf + len, sizeof buf - len, "%c128", ch)) > 0)
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len += n;
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ch = '/';
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}
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if (val & MPPE_OPT_56BIT) {
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if ((n = snprintf(buf + len, sizeof buf - len, "%c56", ch)) > 0)
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len += n;
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ch = '/';
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}
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if (val & MPPE_OPT_40BIT) {
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if ((n = snprintf(buf + len, sizeof buf - len, "%c40", ch)) > 0)
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len += n;
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ch = '/';
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}
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}
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if ((n = snprintf(buf + len, sizeof buf - len, " bits, state%s",
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(val & MPPE_OPT_STATELESS) ? "less" : "ful")) > 0)
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len += n;
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if (val & MPPE_OPT_COMPRESSED) {
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if ((n = snprintf(buf + len, sizeof buf - len, ", compressed")) > 0)
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len += n;
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}
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snprintf(buf + len, sizeof buf - len, ")");
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return buf;
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}
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static int
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MPPEUsable(struct fsm *fp)
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{
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int ok;
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#ifndef NORADIUS
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struct radius *r = &fp->bundle->radius;
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/*
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* If the radius server gave us RAD_MICROSOFT_MS_MPPE_ENCRYPTION_TYPES,
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* use that instead of our configuration value.
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*/
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if (*r->cfg.file) {
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ok = r->mppe.sendkeylen && r->mppe.recvkeylen;
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if (!ok)
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log_Printf(LogCCP, "MPPE: Not permitted by RADIUS server\n");
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} else
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#endif
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{
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struct lcp *lcp = &fp->link->lcp;
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ok = (lcp->want_auth == PROTO_CHAP && lcp->want_authtype == 0x81) ||
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(lcp->his_auth == PROTO_CHAP && lcp->his_authtype == 0x81);
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if (!ok)
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log_Printf(LogCCP, "MPPE: Not usable without CHAP81\n");
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}
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return ok;
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}
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static int
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MPPERequired(struct fsm *fp)
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{
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#ifndef NORADIUS
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/*
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* If the radius server gave us RAD_MICROSOFT_MS_MPPE_ENCRYPTION_POLICY,
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* use that instead of our configuration value.
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*/
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if (*fp->bundle->radius.cfg.file && fp->bundle->radius.mppe.policy)
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return fp->bundle->radius.mppe.policy == MPPE_POLICY_REQUIRED ? 1 : 0;
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#endif
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return fp->link->ccp.cfg.mppe.required;
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}
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static u_int32_t
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MPPE_ConfigVal(struct bundle *bundle, const struct ccp_config *cfg)
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{
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u_int32_t val;
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val = cfg->mppe.state == MPPE_STATELESS ? MPPE_OPT_STATELESS : 0;
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#ifndef NORADIUS
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/*
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* If the radius server gave us RAD_MICROSOFT_MS_MPPE_ENCRYPTION_TYPES,
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* use that instead of our configuration value.
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*/
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if (*bundle->radius.cfg.file && bundle->radius.mppe.types) {
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if (bundle->radius.mppe.types & MPPE_TYPE_40BIT)
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val |= MPPE_OPT_40BIT;
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if (bundle->radius.mppe.types & MPPE_TYPE_128BIT)
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val |= MPPE_OPT_128BIT;
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} else
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#endif
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switch(cfg->mppe.keybits) {
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case 128:
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val |= MPPE_OPT_128BIT;
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break;
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case 56:
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val |= MPPE_OPT_56BIT;
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break;
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case 40:
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val |= MPPE_OPT_40BIT;
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break;
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case 0:
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val |= MPPE_OPT_128BIT | MPPE_OPT_56BIT | MPPE_OPT_40BIT;
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break;
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}
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return val;
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}
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|
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/*
|
|
* What options should we use for our first configure request
|
|
*/
|
|
static void
|
|
MPPEInitOptsOutput(struct bundle *bundle, struct fsm_opt *o,
|
|
const struct ccp_config *cfg)
|
|
{
|
|
u_int32_t mval;
|
|
|
|
o->hdr.len = 6;
|
|
|
|
if (!MPPE_MasterKeyValid) {
|
|
log_Printf(LogCCP, "MPPE: MasterKey is invalid,"
|
|
" MPPE is available only with CHAP81 authentication\n");
|
|
ua_htonl(0x0, o->data);
|
|
return;
|
|
}
|
|
|
|
|
|
mval = MPPE_ConfigVal(bundle, cfg);
|
|
ua_htonl(&mval, o->data);
|
|
}
|
|
|
|
/*
|
|
* Our CCP request was NAK'd with the given options
|
|
*/
|
|
static int
|
|
MPPESetOptsOutput(struct bundle *bundle, struct fsm_opt *o,
|
|
const struct ccp_config *cfg)
|
|
{
|
|
u_int32_t mval, peer;
|
|
|
|
ua_ntohl(o->data, &peer);
|
|
|
|
if (!MPPE_MasterKeyValid)
|
|
/* Treat their NAK as a REJ */
|
|
return MODE_NAK;
|
|
|
|
mval = MPPE_ConfigVal(bundle, cfg);
|
|
|
|
/*
|
|
* If we haven't been configured with a specific number of keybits, allow
|
|
* whatever the peer asks for.
|
|
*/
|
|
if (!cfg->mppe.keybits) {
|
|
mval &= ~MPPE_OPT_BITMASK;
|
|
mval |= (peer & MPPE_OPT_BITMASK);
|
|
if (!(mval & MPPE_OPT_BITMASK))
|
|
mval |= MPPE_OPT_128BIT;
|
|
}
|
|
|
|
/* Adjust our statelessness */
|
|
if (cfg->mppe.state == MPPE_ANYSTATE) {
|
|
mval &= ~MPPE_OPT_STATELESS;
|
|
mval |= (peer & MPPE_OPT_STATELESS);
|
|
}
|
|
|
|
ua_htonl(&mval, o->data);
|
|
|
|
return MODE_ACK;
|
|
}
|
|
|
|
/*
|
|
* The peer has requested the given options
|
|
*/
|
|
static int
|
|
MPPESetOptsInput(struct bundle *bundle, struct fsm_opt *o,
|
|
const struct ccp_config *cfg)
|
|
{
|
|
u_int32_t mval, peer;
|
|
int res = MODE_ACK;
|
|
|
|
ua_ntohl(o->data, &peer);
|
|
if (!MPPE_MasterKeyValid) {
|
|
if (peer != 0) {
|
|
peer = 0;
|
|
ua_htonl(&peer, o->data);
|
|
return MODE_NAK;
|
|
} else
|
|
return MODE_ACK;
|
|
}
|
|
|
|
mval = MPPE_ConfigVal(bundle, cfg);
|
|
|
|
if (peer & ~MPPE_OPT_MASK)
|
|
/* He's asking for bits we don't know about */
|
|
res = MODE_NAK;
|
|
|
|
if (peer & MPPE_OPT_STATELESS) {
|
|
if (cfg->mppe.state == MPPE_STATEFUL)
|
|
/* Peer can't have stateless */
|
|
res = MODE_NAK;
|
|
else
|
|
/* Peer wants stateless, that's ok */
|
|
mval |= MPPE_OPT_STATELESS;
|
|
} else {
|
|
if (cfg->mppe.state == MPPE_STATELESS)
|
|
/* Peer must have stateless */
|
|
res = MODE_NAK;
|
|
else
|
|
/* Peer doesn't want stateless, that's ok */
|
|
mval &= ~MPPE_OPT_STATELESS;
|
|
}
|
|
|
|
/* If we've got a configured number of keybits - the peer must use that */
|
|
if (cfg->mppe.keybits) {
|
|
ua_htonl(&mval, o->data);
|
|
return peer == mval ? res : MODE_NAK;
|
|
}
|
|
|
|
/* If a specific number of bits hasn't been requested, we'll need to NAK */
|
|
switch (peer & MPPE_OPT_BITMASK) {
|
|
case MPPE_OPT_128BIT:
|
|
case MPPE_OPT_56BIT:
|
|
case MPPE_OPT_40BIT:
|
|
break;
|
|
default:
|
|
res = MODE_NAK;
|
|
}
|
|
|
|
/* Suggest the best number of bits */
|
|
mval &= ~MPPE_OPT_BITMASK;
|
|
if (peer & MPPE_OPT_128BIT)
|
|
mval |= MPPE_OPT_128BIT;
|
|
else if (peer & MPPE_OPT_56BIT)
|
|
mval |= MPPE_OPT_56BIT;
|
|
else if (peer & MPPE_OPT_40BIT)
|
|
mval |= MPPE_OPT_40BIT;
|
|
else
|
|
mval |= MPPE_OPT_128BIT;
|
|
ua_htonl(&mval, o->data);
|
|
|
|
return res;
|
|
}
|
|
|
|
static struct mppe_state *
|
|
MPPE_InitState(struct fsm_opt *o)
|
|
{
|
|
struct mppe_state *mp;
|
|
u_int32_t val;
|
|
|
|
if ((mp = calloc(1, sizeof *mp)) != NULL) {
|
|
ua_ntohl(o->data, &val);
|
|
|
|
switch (val & MPPE_OPT_BITMASK) {
|
|
case MPPE_OPT_128BIT:
|
|
mp->keylen = 16;
|
|
mp->keybits = 128;
|
|
break;
|
|
case MPPE_OPT_56BIT:
|
|
mp->keylen = 8;
|
|
mp->keybits = 56;
|
|
break;
|
|
case MPPE_OPT_40BIT:
|
|
mp->keylen = 8;
|
|
mp->keybits = 40;
|
|
break;
|
|
default:
|
|
log_Printf(LogWARN, "Unexpected MPPE options 0x%08x\n", val);
|
|
free(mp);
|
|
return NULL;
|
|
}
|
|
|
|
mp->stateless = !!(val & MPPE_OPT_STATELESS);
|
|
}
|
|
|
|
return mp;
|
|
}
|
|
|
|
static void *
|
|
MPPEInitInput(struct bundle *bundle, struct fsm_opt *o)
|
|
{
|
|
struct mppe_state *mip;
|
|
|
|
if (!MPPE_MasterKeyValid) {
|
|
log_Printf(LogWARN, "MPPE: Cannot initialise without CHAP81\n");
|
|
return NULL;
|
|
}
|
|
|
|
if ((mip = MPPE_InitState(o)) == NULL) {
|
|
log_Printf(LogWARN, "MPPEInput: Cannot initialise - unexpected options\n");
|
|
return NULL;
|
|
}
|
|
|
|
log_Printf(LogDEBUG, "MPPE: InitInput: %d-bits\n", mip->keybits);
|
|
|
|
#ifndef NORADIUS
|
|
if (*bundle->radius.cfg.file && bundle->radius.mppe.recvkey) {
|
|
if (mip->keylen > bundle->radius.mppe.recvkeylen)
|
|
mip->keylen = bundle->radius.mppe.recvkeylen;
|
|
if (mip->keylen > sizeof mip->mastkey)
|
|
mip->keylen = sizeof mip->mastkey;
|
|
memcpy(mip->mastkey, bundle->radius.mppe.recvkey, mip->keylen);
|
|
} else
|
|
#endif
|
|
GetAsymetricStartKey(MPPE_MasterKey, mip->mastkey, mip->keylen, 0,
|
|
MPPE_IsServer);
|
|
|
|
GetNewKeyFromSHA(mip->mastkey, mip->mastkey, mip->keylen, mip->sesskey);
|
|
|
|
MPPEReduceSessionKey(mip);
|
|
|
|
log_Printf(LogCCP, "MPPE: Input channel initiated\n");
|
|
|
|
if (!mip->stateless) {
|
|
/*
|
|
* We need to initialise our dictionary here as the first packet we
|
|
* receive is unlikely to have the FLUSHED bit set.
|
|
*/
|
|
log_Printf(LogDEBUG, "MPPEInitInput: Dictionary initialised [%d]\n",
|
|
mip->cohnum);
|
|
RC4_set_key(&mip->rc4key, mip->keylen, mip->sesskey);
|
|
} else {
|
|
/*
|
|
* We do the first key change here as the first packet is expected
|
|
* to have a sequence number of 0 and we'll therefore not expect
|
|
* to have to change the key at that point.
|
|
*/
|
|
log_Printf(LogDEBUG, "MPPEInitInput: Key changed [%d]\n", mip->cohnum);
|
|
MPPEKeyChange(mip);
|
|
}
|
|
|
|
return mip;
|
|
}
|
|
|
|
static void *
|
|
MPPEInitOutput(struct bundle *bundle, struct fsm_opt *o)
|
|
{
|
|
struct mppe_state *mop;
|
|
|
|
if (!MPPE_MasterKeyValid) {
|
|
log_Printf(LogWARN, "MPPE: Cannot initialise without CHAP81\n");
|
|
return NULL;
|
|
}
|
|
|
|
if ((mop = MPPE_InitState(o)) == NULL) {
|
|
log_Printf(LogWARN, "MPPEOutput: Cannot initialise - unexpected options\n");
|
|
return NULL;
|
|
}
|
|
|
|
log_Printf(LogDEBUG, "MPPE: InitOutput: %d-bits\n", mop->keybits);
|
|
|
|
#ifndef NORADIUS
|
|
if (*bundle->radius.cfg.file && bundle->radius.mppe.sendkey) {
|
|
if (mop->keylen > bundle->radius.mppe.sendkeylen)
|
|
mop->keylen = bundle->radius.mppe.sendkeylen;
|
|
if (mop->keylen > sizeof mop->mastkey)
|
|
mop->keylen = sizeof mop->mastkey;
|
|
memcpy(mop->mastkey, bundle->radius.mppe.sendkey, mop->keylen);
|
|
} else
|
|
#endif
|
|
GetAsymetricStartKey(MPPE_MasterKey, mop->mastkey, mop->keylen, 1,
|
|
MPPE_IsServer);
|
|
|
|
GetNewKeyFromSHA(mop->mastkey, mop->mastkey, mop->keylen, mop->sesskey);
|
|
|
|
MPPEReduceSessionKey(mop);
|
|
|
|
log_Printf(LogCCP, "MPPE: Output channel initiated\n");
|
|
|
|
if (!mop->stateless) {
|
|
/*
|
|
* We need to initialise our dictionary now as the first packet we
|
|
* send won't have the FLUSHED bit set.
|
|
*/
|
|
log_Printf(LogDEBUG, "MPPEInitOutput: Dictionary initialised [%d]\n",
|
|
mop->cohnum);
|
|
RC4_set_key(&mop->rc4key, mop->keylen, mop->sesskey);
|
|
}
|
|
|
|
return mop;
|
|
}
|
|
|
|
static void
|
|
MPPETermInput(void *v)
|
|
{
|
|
free(v);
|
|
}
|
|
|
|
static void
|
|
MPPETermOutput(void *v)
|
|
{
|
|
free(v);
|
|
}
|
|
|
|
const struct ccp_algorithm MPPEAlgorithm = {
|
|
TY_MPPE,
|
|
CCP_NEG_MPPE,
|
|
MPPEDispOpts,
|
|
MPPEUsable,
|
|
MPPERequired,
|
|
{
|
|
MPPESetOptsInput,
|
|
MPPEInitInput,
|
|
MPPETermInput,
|
|
MPPEResetInput,
|
|
MPPEInput,
|
|
MPPEDictSetup
|
|
},
|
|
{
|
|
2,
|
|
MPPEInitOptsOutput,
|
|
MPPESetOptsOutput,
|
|
MPPEInitOutput,
|
|
MPPETermOutput,
|
|
MPPEResetOutput,
|
|
MPPEOutput
|
|
},
|
|
};
|