freebsd-skq/usr.sbin/ppp/chap_ms.c
pfg 7551d83c35 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

418 lines
12 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 1997 Gabor Kincses <gabor@acm.org>
* 1997 - 2001 Brian Somers <brian@Awfulhak.org>
* based on work by Eric Rosenquist
* Strata Software Limited.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <ctype.h>
#ifdef __FreeBSD__
#include <openssl/des.h>
#include <sha.h>
#else
#include <sys/types.h>
#include <stdlib.h>
#ifdef __NetBSD__
#include <openssl/des.h>
#else
#include <des.h>
#endif
#include <openssl/sha.h>
#endif
#include <md4.h>
#include <string.h>
#include "chap_ms.h"
/*
* Documentation & specifications:
*
* MS-CHAP (CHAP80) rfc2433
* MS-CHAP-V2 (CHAP81) rfc2759
* MPPE key management draft-ietf-pppext-mppe-keys-02.txt
*/
static char SHA1_Pad1[40] =
{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
static char SHA1_Pad2[40] =
{0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2,
0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2,
0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2,
0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2};
/* unused, for documentation only */
/* only NTResp is filled in for FreeBSD */
struct MS_ChapResponse {
u_char LANManResp[24];
u_char NTResp[24];
u_char UseNT; /* If 1, ignore the LANMan response field */
};
static u_char
Get7Bits(u_char *input, int startBit)
{
register unsigned int word;
word = (unsigned)input[startBit / 8] << 8;
word |= (unsigned)input[startBit / 8 + 1];
word >>= 15 - (startBit % 8 + 7);
return word & 0xFE;
}
/* IN 56 bit DES key missing parity bits
OUT 64 bit DES key with parity bits added */
static void
MakeKey(u_char *key, u_char *des_key)
{
des_key[0] = Get7Bits(key, 0);
des_key[1] = Get7Bits(key, 7);
des_key[2] = Get7Bits(key, 14);
des_key[3] = Get7Bits(key, 21);
des_key[4] = Get7Bits(key, 28);
des_key[5] = Get7Bits(key, 35);
des_key[6] = Get7Bits(key, 42);
des_key[7] = Get7Bits(key, 49);
des_set_odd_parity((des_cblock *)des_key);
}
static void /* IN 8 octets IN 7 octest OUT 8 octets */
DesEncrypt(u_char *clear, u_char *key, u_char *cipher)
{
des_cblock des_key;
des_key_schedule key_schedule;
MakeKey(key, des_key);
des_set_key(&des_key, key_schedule);
des_ecb_encrypt((des_cblock *)clear, (des_cblock *)cipher, key_schedule, 1);
}
static void /* IN 8 octets IN 16 octets OUT 24 octets */
ChallengeResponse(u_char *challenge, u_char *pwHash, u_char *response)
{
char ZPasswordHash[21];
memset(ZPasswordHash, '\0', sizeof ZPasswordHash);
memcpy(ZPasswordHash, pwHash, 16);
DesEncrypt(challenge, ZPasswordHash + 0, response + 0);
DesEncrypt(challenge, ZPasswordHash + 7, response + 8);
DesEncrypt(challenge, ZPasswordHash + 14, response + 16);
}
void
NtPasswordHash(char *key, int keylen, char *hash)
{
MD4_CTX MD4context;
MD4Init(&MD4context);
MD4Update(&MD4context, key, keylen);
MD4Final(hash, &MD4context);
}
void
HashNtPasswordHash(char *hash, char *hashhash)
{
MD4_CTX MD4context;
MD4Init(&MD4context);
MD4Update(&MD4context, hash, 16);
MD4Final(hashhash, &MD4context);
}
static void
ChallengeHash(char *PeerChallenge, char *AuthenticatorChallenge,
char *UserName, char *Challenge)
{
SHA_CTX Context;
char Digest[SHA_DIGEST_LENGTH];
char *Name;
Name = strrchr(UserName, '\\');
if(NULL == Name)
Name = UserName;
else
Name++;
SHA1_Init(&Context);
SHA1_Update(&Context, PeerChallenge, 16);
SHA1_Update(&Context, AuthenticatorChallenge, 16);
SHA1_Update(&Context, Name, strlen(Name));
SHA1_Final(Digest, &Context);
memcpy(Challenge, Digest, 8);
}
void
GenerateNTResponse(char *AuthenticatorChallenge, char *PeerChallenge,
char *UserName, char *Password,
int PasswordLen, char *Response)
{
char Challenge[8];
char PasswordHash[16];
ChallengeHash(PeerChallenge, AuthenticatorChallenge, UserName, Challenge);
NtPasswordHash(Password, PasswordLen, PasswordHash);
ChallengeResponse(Challenge, PasswordHash, Response);
}
#ifndef __FreeBSD__
#define LENGTH 20
static char *
SHA1_End(SHA_CTX *ctx, char *buf)
{
int i;
unsigned char digest[LENGTH];
static const char hex[]="0123456789abcdef";
if (!buf)
buf = malloc(2*LENGTH + 1);
if (!buf)
return 0;
SHA1_Final(digest, ctx);
for (i = 0; i < LENGTH; i++) {
buf[i+i] = hex[digest[i] >> 4];
buf[i+i+1] = hex[digest[i] & 0x0f];
}
buf[i+i] = '\0';
return buf;
}
#endif
void
GenerateAuthenticatorResponse(char *Password, int PasswordLen,
char *NTResponse, char *PeerChallenge,
char *AuthenticatorChallenge, char *UserName,
char *AuthenticatorResponse)
{
SHA_CTX Context;
char PasswordHash[16];
char PasswordHashHash[16];
char Challenge[8];
u_char Digest[SHA_DIGEST_LENGTH];
int i;
/*
* "Magic" constants used in response generation
*/
char Magic1[39] =
{0x4D, 0x61, 0x67, 0x69, 0x63, 0x20, 0x73, 0x65, 0x72, 0x76,
0x65, 0x72, 0x20, 0x74, 0x6F, 0x20, 0x63, 0x6C, 0x69, 0x65,
0x6E, 0x74, 0x20, 0x73, 0x69, 0x67, 0x6E, 0x69, 0x6E, 0x67,
0x20, 0x63, 0x6F, 0x6E, 0x73, 0x74, 0x61, 0x6E, 0x74};
char Magic2[41] =
{0x50, 0x61, 0x64, 0x20, 0x74, 0x6F, 0x20, 0x6D, 0x61, 0x6B,
0x65, 0x20, 0x69, 0x74, 0x20, 0x64, 0x6F, 0x20, 0x6D, 0x6F,
0x72, 0x65, 0x20, 0x74, 0x68, 0x61, 0x6E, 0x20, 0x6F, 0x6E,
0x65, 0x20, 0x69, 0x74, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6F,
0x6E};
/*
* Hash the password with MD4
*/
NtPasswordHash(Password, PasswordLen, PasswordHash);
/*
* Now hash the hash
*/
HashNtPasswordHash(PasswordHash, PasswordHashHash);
SHA1_Init(&Context);
SHA1_Update(&Context, PasswordHashHash, 16);
SHA1_Update(&Context, NTResponse, 24);
SHA1_Update(&Context, Magic1, 39);
SHA1_Final(Digest, &Context);
ChallengeHash(PeerChallenge, AuthenticatorChallenge, UserName, Challenge);
SHA1_Init(&Context);
SHA1_Update(&Context, Digest, 20);
SHA1_Update(&Context, Challenge, 8);
SHA1_Update(&Context, Magic2, 41);
/*
* Encode the value of 'Digest' as "S=" followed by
* 40 ASCII hexadecimal digits and return it in
* AuthenticatorResponse.
* For example,
* "S=0123456789ABCDEF0123456789ABCDEF01234567"
*/
AuthenticatorResponse[0] = 'S';
AuthenticatorResponse[1] = '=';
SHA1_End(&Context, AuthenticatorResponse + 2);
for (i=2; i<42; i++)
AuthenticatorResponse[i] = toupper(AuthenticatorResponse[i]);
}
void
GetMasterKey(char *PasswordHashHash, char *NTResponse, char *MasterKey)
{
char Digest[SHA_DIGEST_LENGTH];
SHA_CTX Context;
static char Magic1[27] =
{0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74,
0x68, 0x65, 0x20, 0x4d, 0x50, 0x50, 0x45, 0x20, 0x4d,
0x61, 0x73, 0x74, 0x65, 0x72, 0x20, 0x4b, 0x65, 0x79};
SHA1_Init(&Context);
SHA1_Update(&Context, PasswordHashHash, 16);
SHA1_Update(&Context, NTResponse, 24);
SHA1_Update(&Context, Magic1, 27);
SHA1_Final(Digest, &Context);
memcpy(MasterKey, Digest, 16);
}
void
GetAsymetricStartKey(char *MasterKey, char *SessionKey, int SessionKeyLength,
int IsSend, int IsServer)
{
char Digest[SHA_DIGEST_LENGTH];
SHA_CTX Context;
char *s;
static char Magic2[84] =
{0x4f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x69,
0x65, 0x6e, 0x74, 0x20, 0x73, 0x69, 0x64, 0x65, 0x2c, 0x20,
0x74, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
0x65, 0x20, 0x73, 0x65, 0x6e, 0x64, 0x20, 0x6b, 0x65, 0x79,
0x3b, 0x20, 0x6f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x73,
0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x73, 0x69, 0x64, 0x65,
0x2c, 0x20, 0x69, 0x74, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
0x65, 0x20, 0x72, 0x65, 0x63, 0x65, 0x69, 0x76, 0x65, 0x20,
0x6b, 0x65, 0x79, 0x2e};
static char Magic3[84] =
{0x4f, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x69,
0x65, 0x6e, 0x74, 0x20, 0x73, 0x69, 0x64, 0x65, 0x2c, 0x20,
0x74, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74, 0x68,
0x65, 0x20, 0x72, 0x65, 0x63, 0x65, 0x69, 0x76, 0x65, 0x20,
0x6b, 0x65, 0x79, 0x3b, 0x20, 0x6f, 0x6e, 0x20, 0x74, 0x68,
0x65, 0x20, 0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x73,
0x69, 0x64, 0x65, 0x2c, 0x20, 0x69, 0x74, 0x20, 0x69, 0x73,
0x20, 0x74, 0x68, 0x65, 0x20, 0x73, 0x65, 0x6e, 0x64, 0x20,
0x6b, 0x65, 0x79, 0x2e};
if (IsSend) {
if (IsServer) {
s = Magic3;
} else {
s = Magic2;
}
} else {
if (IsServer) {
s = Magic2;
} else {
s = Magic3;
}
}
SHA1_Init(&Context);
SHA1_Update(&Context, MasterKey, 16);
SHA1_Update(&Context, SHA1_Pad1, 40);
SHA1_Update(&Context, s, 84);
SHA1_Update(&Context, SHA1_Pad2, 40);
SHA1_Final(Digest, &Context);
memcpy(SessionKey, Digest, SessionKeyLength);
}
void
GetNewKeyFromSHA(char *StartKey, char *SessionKey, long SessionKeyLength,
char *InterimKey)
{
SHA_CTX Context;
char Digest[SHA_DIGEST_LENGTH];
SHA1_Init(&Context);
SHA1_Update(&Context, StartKey, SessionKeyLength);
SHA1_Update(&Context, SHA1_Pad1, 40);
SHA1_Update(&Context, SessionKey, SessionKeyLength);
SHA1_Update(&Context, SHA1_Pad2, 40);
SHA1_Final(Digest, &Context);
memcpy(InterimKey, Digest, SessionKeyLength);
}
#if 0
static void
Get_Key(char *InitialSessionKey, char *CurrentSessionKey,
int LengthOfDesiredKey)
{
SHA_CTX Context;
char Digest[SHA_DIGEST_LENGTH];
SHA1_Init(&Context);
SHA1_Update(&Context, InitialSessionKey, LengthOfDesiredKey);
SHA1_Update(&Context, SHA1_Pad1, 40);
SHA1_Update(&Context, CurrentSessionKey, LengthOfDesiredKey);
SHA1_Update(&Context, SHA1_Pad2, 40);
SHA1_Final(Digest, &Context);
memcpy(CurrentSessionKey, Digest, LengthOfDesiredKey);
}
#endif
/* passwordHash 16-bytes MD4 hashed password
challenge 8-bytes peer CHAP challenge
since passwordHash is in a 24-byte buffer, response is written in there */
void
mschap_NT(char *passwordHash, char *challenge)
{
u_char response[24];
ChallengeResponse(challenge, passwordHash, response);
memcpy(passwordHash, response, 24);
passwordHash[24] = 1; /* NT-style response */
}
void
mschap_LANMan(char *digest, char *challenge, char *secret)
{
static u_char salt[] = "KGS!@#$%"; /* RASAPI32.dll */
char SECRET[14], *ptr, *end;
u_char hash[16];
end = SECRET + sizeof SECRET;
for (ptr = SECRET; *secret && ptr < end; ptr++, secret++)
*ptr = toupper(*secret);
if (ptr < end)
memset(ptr, '\0', end - ptr);
DesEncrypt(salt, SECRET, hash);
DesEncrypt(salt, SECRET + 7, hash + 8);
ChallengeResponse(challenge, hash, digest);
}