/* * chap_ms.c - Microsoft MS-CHAP compatible implementation. * * Copyright (c) 1995 Eric Rosenquist. 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 name(s) of the authors of this software must not be used to * endorse or promote products derived from this software without * prior written permission. * * 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. */ /* * Modifications by Lauri Pesonen / lpesonen@clinet.fi, april 1997 * * Implemented LANManager type password response to MS-CHAP challenges. * Now pppd provides both NT style and LANMan style blocks, and the * prefered is set by option "ms-lanman". Default is to use NT. * The hash text (StdText) was taken from Win95 RASAPI32.DLL. * * You should also use DOMAIN\\USERNAME as described in README.MSCHAP80 */ /* * Modifications by Frank Cusack, frank@google.com, March 2002. * * Implemented MS-CHAPv2 functionality, heavily based on sample * implementation in RFC 2759. Implemented MPPE functionality, * heavily based on sample implementation in RFC 3079. * * Copyright (c) 2002 Google, Inc. 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 name(s) of the authors of this software must not be used to * endorse or promote products derived from this software without * prior written permission. * * 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. * */ #include "netif/ppp/ppp_opts.h" #if PPP_SUPPORT && MSCHAP_SUPPORT /* don't build if not configured for use in lwipopts.h */ #if 0 /* UNUSED */ #include #include #include #include #include #include #include #endif /* UNUSED */ #include "netif/ppp/ppp_impl.h" #include "netif/ppp/chap-new.h" #include "netif/ppp/chap_ms.h" #include "netif/ppp/pppcrypt.h" #include "netif/ppp/magic.h" #if MPPE_SUPPORT #include "netif/ppp/mppe.h" /* For mppe_sha1_pad*, mppe_set_key() */ #endif /* MPPE_SUPPORT */ #define SHA1_SIGNATURE_SIZE 20 #define MD4_SIGNATURE_SIZE 16 /* 16 bytes in a MD4 message digest */ #define MAX_NT_PASSWORD 256 /* Max (Unicode) chars in an NT pass */ #define MS_CHAP_RESPONSE_LEN 49 /* Response length for MS-CHAP */ #define MS_CHAP2_RESPONSE_LEN 49 /* Response length for MS-CHAPv2 */ #define MS_AUTH_RESPONSE_LENGTH 40 /* MS-CHAPv2 authenticator response, */ /* as ASCII */ /* Error codes for MS-CHAP failure messages. */ #define MS_CHAP_ERROR_RESTRICTED_LOGON_HOURS 646 #define MS_CHAP_ERROR_ACCT_DISABLED 647 #define MS_CHAP_ERROR_PASSWD_EXPIRED 648 #define MS_CHAP_ERROR_NO_DIALIN_PERMISSION 649 #define MS_CHAP_ERROR_AUTHENTICATION_FAILURE 691 #define MS_CHAP_ERROR_CHANGING_PASSWORD 709 /* * Offsets within the response field for MS-CHAP */ #define MS_CHAP_LANMANRESP 0 #define MS_CHAP_LANMANRESP_LEN 24 #define MS_CHAP_NTRESP 24 #define MS_CHAP_NTRESP_LEN 24 #define MS_CHAP_USENT 48 /* * Offsets within the response field for MS-CHAP2 */ #define MS_CHAP2_PEER_CHALLENGE 0 #define MS_CHAP2_PEER_CHAL_LEN 16 #define MS_CHAP2_RESERVED_LEN 8 #define MS_CHAP2_NTRESP 24 #define MS_CHAP2_NTRESP_LEN 24 #define MS_CHAP2_FLAGS 48 #if MPPE_SUPPORT #if 0 /* UNUSED */ /* These values are the RADIUS attribute values--see RFC 2548. */ #define MPPE_ENC_POL_ENC_ALLOWED 1 #define MPPE_ENC_POL_ENC_REQUIRED 2 #define MPPE_ENC_TYPES_RC4_40 2 #define MPPE_ENC_TYPES_RC4_128 4 /* used by plugins (using above values) */ extern void set_mppe_enc_types(int, int); #endif /* UNUSED */ #endif /* MPPE_SUPPORT */ /* Are we the authenticator or authenticatee? For MS-CHAPv2 key derivation. */ #define MS_CHAP2_AUTHENTICATEE 0 #define MS_CHAP2_AUTHENTICATOR 1 static void ascii2unicode (const char[], int, u_char[]); static void NTPasswordHash (u_char *, int, u_char[MD4_SIGNATURE_SIZE]); static void ChallengeResponse (const u_char *, const u_char *, u_char[24]); static void ChallengeHash (const u_char[16], const u_char *, const char *, u_char[8]); static void ChapMS_NT (const u_char *, const char *, int, u_char[24]); static void ChapMS2_NT (const u_char *, const u_char[16], const char *, const char *, int, u_char[24]); static void GenerateAuthenticatorResponsePlain (const char*, int, u_char[24], const u_char[16], const u_char *, const char *, u_char[41]); #ifdef MSLANMAN static void ChapMS_LANMan (u_char *, char *, int, u_char *); #endif static void GenerateAuthenticatorResponse(const u_char PasswordHashHash[MD4_SIGNATURE_SIZE], u_char NTResponse[24], const u_char PeerChallenge[16], const u_char *rchallenge, const char *username, u_char authResponse[MS_AUTH_RESPONSE_LENGTH+1]); #if MPPE_SUPPORT static void Set_Start_Key (ppp_pcb *pcb, const u_char *, const char *, int); static void SetMasterKeys (ppp_pcb *pcb, const char *, int, u_char[24], int); #endif /* MPPE_SUPPORT */ static void ChapMS (ppp_pcb *pcb, const u_char *, const char *, int, u_char *); static void ChapMS2 (ppp_pcb *pcb, const u_char *, const u_char *, const char *, const char *, int, u_char *, u_char[MS_AUTH_RESPONSE_LENGTH+1], int); #ifdef MSLANMAN bool ms_lanman = 0; /* Use LanMan password instead of NT */ /* Has meaning only with MS-CHAP challenges */ #endif #if MPPE_SUPPORT #ifdef DEBUGMPPEKEY /* For MPPE debug */ /* Use "[]|}{?/><,`!2&&(" (sans quotes) for RFC 3079 MS-CHAPv2 test value */ static char *mschap_challenge = NULL; /* Use "!@\#$%^&*()_+:3|~" (sans quotes, backslash is to escape #) for ... */ static char *mschap2_peer_challenge = NULL; #endif #include "netif/ppp/fsm.h" /* Need to poke MPPE options */ #include "netif/ppp/ccp.h" #endif /* MPPE_SUPPORT */ #if PPP_OPTIONS /* * Command-line options. */ static option_t chapms_option_list[] = { #ifdef MSLANMAN { "ms-lanman", o_bool, &ms_lanman, "Use LanMan passwd when using MS-CHAP", 1 }, #endif #ifdef DEBUGMPPEKEY { "mschap-challenge", o_string, &mschap_challenge, "specify CHAP challenge" }, { "mschap2-peer-challenge", o_string, &mschap2_peer_challenge, "specify CHAP peer challenge" }, #endif { NULL } }; #endif /* PPP_OPTIONS */ #if PPP_SERVER /* * chapms_generate_challenge - generate a challenge for MS-CHAP. * For MS-CHAP the challenge length is fixed at 8 bytes. * The length goes in challenge[0] and the actual challenge starts * at challenge[1]. */ static void chapms_generate_challenge(ppp_pcb *pcb, unsigned char *challenge) { LWIP_UNUSED_ARG(pcb); *challenge++ = 8; #ifdef DEBUGMPPEKEY if (mschap_challenge && strlen(mschap_challenge) == 8) memcpy(challenge, mschap_challenge, 8); else #endif magic_random_bytes(challenge, 8); } static void chapms2_generate_challenge(ppp_pcb *pcb, unsigned char *challenge) { LWIP_UNUSED_ARG(pcb); *challenge++ = 16; #ifdef DEBUGMPPEKEY if (mschap_challenge && strlen(mschap_challenge) == 16) memcpy(challenge, mschap_challenge, 16); else #endif magic_random_bytes(challenge, 16); } static int chapms_verify_response(ppp_pcb *pcb, int id, const char *name, const unsigned char *secret, int secret_len, const unsigned char *challenge, const unsigned char *response, char *message, int message_space) { unsigned char md[MS_CHAP_RESPONSE_LEN]; int diff; int challenge_len, response_len; LWIP_UNUSED_ARG(id); LWIP_UNUSED_ARG(name); challenge_len = *challenge++; /* skip length, is 8 */ response_len = *response++; if (response_len != MS_CHAP_RESPONSE_LEN) goto bad; #ifndef MSLANMAN if (!response[MS_CHAP_USENT]) { /* Should really propagate this into the error packet. */ ppp_notice("Peer request for LANMAN auth not supported"); goto bad; } #endif /* Generate the expected response. */ ChapMS(pcb, (const u_char *)challenge, (const char *)secret, secret_len, md); #ifdef MSLANMAN /* Determine which part of response to verify against */ if (!response[MS_CHAP_USENT]) diff = memcmp(&response[MS_CHAP_LANMANRESP], &md[MS_CHAP_LANMANRESP], MS_CHAP_LANMANRESP_LEN); else #endif diff = memcmp(&response[MS_CHAP_NTRESP], &md[MS_CHAP_NTRESP], MS_CHAP_NTRESP_LEN); if (diff == 0) { ppp_slprintf(message, message_space, "Access granted"); return 1; } bad: /* See comments below for MS-CHAP V2 */ ppp_slprintf(message, message_space, "E=691 R=1 C=%0.*B V=0", challenge_len, challenge); return 0; } static int chapms2_verify_response(ppp_pcb *pcb, int id, const char *name, const unsigned char *secret, int secret_len, const unsigned char *challenge, const unsigned char *response, char *message, int message_space) { unsigned char md[MS_CHAP2_RESPONSE_LEN]; char saresponse[MS_AUTH_RESPONSE_LENGTH+1]; int challenge_len, response_len; LWIP_UNUSED_ARG(id); challenge_len = *challenge++; /* skip length, is 16 */ response_len = *response++; if (response_len != MS_CHAP2_RESPONSE_LEN) goto bad; /* not even the right length */ /* Generate the expected response and our mutual auth. */ ChapMS2(pcb, (const u_char*)challenge, (const u_char*)&response[MS_CHAP2_PEER_CHALLENGE], name, (const char *)secret, secret_len, md, (unsigned char *)saresponse, MS_CHAP2_AUTHENTICATOR); /* compare MDs and send the appropriate status */ /* * Per RFC 2759, success message must be formatted as * "S= M=" * where * is the Authenticator Response (mutual auth) * is a text message * * However, some versions of Windows (win98 tested) do not know * about the M= part (required per RFC 2759) and flag * it as an error (reported incorrectly as an encryption error * to the user). Since the RFC requires it, and it can be * useful information, we supply it if the peer is a conforming * system. Luckily (?), win98 sets the Flags field to 0x04 * (contrary to RFC requirements) so we can use that to * distinguish between conforming and non-conforming systems. * * Special thanks to Alex Swiridov for * help debugging this. */ if (memcmp(&md[MS_CHAP2_NTRESP], &response[MS_CHAP2_NTRESP], MS_CHAP2_NTRESP_LEN) == 0) { if (response[MS_CHAP2_FLAGS]) ppp_slprintf(message, message_space, "S=%s", saresponse); else ppp_slprintf(message, message_space, "S=%s M=%s", saresponse, "Access granted"); return 1; } bad: /* * Failure message must be formatted as * "E=e R=r C=c V=v M=m" * where * e = error code (we use 691, ERROR_AUTHENTICATION_FAILURE) * r = retry (we use 1, ok to retry) * c = challenge to use for next response, we reuse previous * v = Change Password version supported, we use 0 * m = text message * * The M=m part is only for MS-CHAPv2. Neither win2k nor * win98 (others untested) display the message to the user anyway. * They also both ignore the E=e code. * * Note that it's safe to reuse the same challenge as we don't * actually accept another response based on the error message * (and no clients try to resend a response anyway). * * Basically, this whole bit is useless code, even the small * implementation here is only because of overspecification. */ ppp_slprintf(message, message_space, "E=691 R=1 C=%0.*B V=0 M=%s", challenge_len, challenge, "Access denied"); return 0; } #endif /* PPP_SERVER */ static void chapms_make_response(ppp_pcb *pcb, unsigned char *response, int id, const char *our_name, const unsigned char *challenge, const char *secret, int secret_len, unsigned char *private_) { LWIP_UNUSED_ARG(id); LWIP_UNUSED_ARG(our_name); LWIP_UNUSED_ARG(private_); challenge++; /* skip length, should be 8 */ *response++ = MS_CHAP_RESPONSE_LEN; ChapMS(pcb, challenge, secret, secret_len, response); } static void chapms2_make_response(ppp_pcb *pcb, unsigned char *response, int id, const char *our_name, const unsigned char *challenge, const char *secret, int secret_len, unsigned char *private_) { LWIP_UNUSED_ARG(id); challenge++; /* skip length, should be 16 */ *response++ = MS_CHAP2_RESPONSE_LEN; ChapMS2(pcb, challenge, #ifdef DEBUGMPPEKEY mschap2_peer_challenge, #else NULL, #endif our_name, secret, secret_len, response, private_, MS_CHAP2_AUTHENTICATEE); } static int chapms2_check_success(ppp_pcb *pcb, unsigned char *msg, int len, unsigned char *private_) { LWIP_UNUSED_ARG(pcb); if ((len < MS_AUTH_RESPONSE_LENGTH + 2) || strncmp((char *)msg, "S=", 2) != 0) { /* Packet does not start with "S=" */ ppp_error("MS-CHAPv2 Success packet is badly formed."); return 0; } msg += 2; len -= 2; if (len < MS_AUTH_RESPONSE_LENGTH || memcmp(msg, private_, MS_AUTH_RESPONSE_LENGTH)) { /* Authenticator Response did not match expected. */ ppp_error("MS-CHAPv2 mutual authentication failed."); return 0; } /* Authenticator Response matches. */ msg += MS_AUTH_RESPONSE_LENGTH; /* Eat it */ len -= MS_AUTH_RESPONSE_LENGTH; if ((len >= 3) && !strncmp((char *)msg, " M=", 3)) { msg += 3; /* Eat the delimiter */ } else if (len) { /* Packet has extra text which does not begin " M=" */ ppp_error("MS-CHAPv2 Success packet is badly formed."); return 0; } return 1; } static void chapms_handle_failure(ppp_pcb *pcb, unsigned char *inp, int len) { int err; const char *p; char msg[64]; LWIP_UNUSED_ARG(pcb); /* We want a null-terminated string for strxxx(). */ len = LWIP_MIN(len, 63); MEMCPY(msg, inp, len); msg[len] = 0; p = msg; /* * Deal with MS-CHAP formatted failure messages; just print the * M= part (if any). For MS-CHAP we're not really supposed * to use M=, but it shouldn't hurt. See * chapms[2]_verify_response. */ if (!strncmp(p, "E=", 2)) err = strtol(p+2, NULL, 10); /* Remember the error code. */ else goto print_msg; /* Message is badly formatted. */ if (len && ((p = strstr(p, " M=")) != NULL)) { /* M= field found. */ p += 3; } else { /* No M=; use the error code. */ switch (err) { case MS_CHAP_ERROR_RESTRICTED_LOGON_HOURS: p = "E=646 Restricted logon hours"; break; case MS_CHAP_ERROR_ACCT_DISABLED: p = "E=647 Account disabled"; break; case MS_CHAP_ERROR_PASSWD_EXPIRED: p = "E=648 Password expired"; break; case MS_CHAP_ERROR_NO_DIALIN_PERMISSION: p = "E=649 No dialin permission"; break; case MS_CHAP_ERROR_AUTHENTICATION_FAILURE: p = "E=691 Authentication failure"; break; case MS_CHAP_ERROR_CHANGING_PASSWORD: /* Should never see this, we don't support Change Password. */ p = "E=709 Error changing password"; break; default: ppp_error("Unknown MS-CHAP authentication failure: %.*v", len, inp); return; } } print_msg: if (p != NULL) ppp_error("MS-CHAP authentication failed: %v", p); } static void ChallengeResponse(const u_char *challenge, const u_char PasswordHash[MD4_SIGNATURE_SIZE], u_char response[24]) { u_char ZPasswordHash[21]; lwip_des_context des; u_char des_key[8]; BZERO(ZPasswordHash, sizeof(ZPasswordHash)); MEMCPY(ZPasswordHash, PasswordHash, MD4_SIGNATURE_SIZE); #if 0 dbglog("ChallengeResponse - ZPasswordHash %.*B", sizeof(ZPasswordHash), ZPasswordHash); #endif pppcrypt_56_to_64_bit_key(ZPasswordHash + 0, des_key); lwip_des_init(&des); lwip_des_setkey_enc(&des, des_key); lwip_des_crypt_ecb(&des, challenge, response +0); lwip_des_free(&des); pppcrypt_56_to_64_bit_key(ZPasswordHash + 7, des_key); lwip_des_init(&des); lwip_des_setkey_enc(&des, des_key); lwip_des_crypt_ecb(&des, challenge, response +8); lwip_des_free(&des); pppcrypt_56_to_64_bit_key(ZPasswordHash + 14, des_key); lwip_des_init(&des); lwip_des_setkey_enc(&des, des_key); lwip_des_crypt_ecb(&des, challenge, response +16); lwip_des_free(&des); #if 0 dbglog("ChallengeResponse - response %.24B", response); #endif } static void ChallengeHash(const u_char PeerChallenge[16], const u_char *rchallenge, const char *username, u_char Challenge[8]) { lwip_sha1_context sha1Context; u_char sha1Hash[SHA1_SIGNATURE_SIZE]; const char *user; /* remove domain from "domain\username" */ if ((user = strrchr(username, '\\')) != NULL) ++user; else user = username; lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, PeerChallenge, 16); lwip_sha1_update(&sha1Context, rchallenge, 16); lwip_sha1_update(&sha1Context, (const unsigned char*)user, strlen(user)); lwip_sha1_finish(&sha1Context, sha1Hash); lwip_sha1_free(&sha1Context); MEMCPY(Challenge, sha1Hash, 8); } /* * Convert the ASCII version of the password to Unicode. * This implicitly supports 8-bit ISO8859/1 characters. * This gives us the little-endian representation, which * is assumed by all M$ CHAP RFCs. (Unicode byte ordering * is machine-dependent.) */ static void ascii2unicode(const char ascii[], int ascii_len, u_char unicode[]) { int i; BZERO(unicode, ascii_len * 2); for (i = 0; i < ascii_len; i++) unicode[i * 2] = (u_char) ascii[i]; } static void NTPasswordHash(u_char *secret, int secret_len, u_char hash[MD4_SIGNATURE_SIZE]) { lwip_md4_context md4Context; lwip_md4_init(&md4Context); lwip_md4_starts(&md4Context); lwip_md4_update(&md4Context, secret, secret_len); lwip_md4_finish(&md4Context, hash); lwip_md4_free(&md4Context); } static void ChapMS_NT(const u_char *rchallenge, const char *secret, int secret_len, u_char NTResponse[24]) { u_char unicodePassword[MAX_NT_PASSWORD * 2]; u_char PasswordHash[MD4_SIGNATURE_SIZE]; /* Hash the Unicode version of the secret (== password). */ ascii2unicode(secret, secret_len, unicodePassword); NTPasswordHash(unicodePassword, secret_len * 2, PasswordHash); ChallengeResponse(rchallenge, PasswordHash, NTResponse); } static void ChapMS2_NT(const u_char *rchallenge, const u_char PeerChallenge[16], const char *username, const char *secret, int secret_len, u_char NTResponse[24]) { u_char unicodePassword[MAX_NT_PASSWORD * 2]; u_char PasswordHash[MD4_SIGNATURE_SIZE]; u_char Challenge[8]; ChallengeHash(PeerChallenge, rchallenge, username, Challenge); /* Hash the Unicode version of the secret (== password). */ ascii2unicode(secret, secret_len, unicodePassword); NTPasswordHash(unicodePassword, secret_len * 2, PasswordHash); ChallengeResponse(Challenge, PasswordHash, NTResponse); } #ifdef MSLANMAN static u_char *StdText = (u_char *)"KGS!@#$%"; /* key from rasapi32.dll */ static void ChapMS_LANMan(u_char *rchallenge, char *secret, int secret_len, unsigned char *response) { int i; u_char UcasePassword[MAX_NT_PASSWORD]; /* max is actually 14 */ u_char PasswordHash[MD4_SIGNATURE_SIZE]; lwip_des_context des; u_char des_key[8]; /* LANMan password is case insensitive */ BZERO(UcasePassword, sizeof(UcasePassword)); for (i = 0; i < secret_len; i++) UcasePassword[i] = (u_char)toupper(secret[i]); pppcrypt_56_to_64_bit_key(UcasePassword +0, des_key); lwip_des_init(&des); lwip_des_setkey_enc(&des, des_key); lwip_des_crypt_ecb(&des, StdText, PasswordHash +0); lwip_des_free(&des); pppcrypt_56_to_64_bit_key(UcasePassword +7, des_key); lwip_des_init(&des); lwip_des_setkey_enc(&des, des_key); lwip_des_crypt_ecb(&des, StdText, PasswordHash +8); lwip_des_free(&des); ChallengeResponse(rchallenge, PasswordHash, &response[MS_CHAP_LANMANRESP]); } #endif static void GenerateAuthenticatorResponse(const u_char PasswordHashHash[MD4_SIGNATURE_SIZE], u_char NTResponse[24], const u_char PeerChallenge[16], const u_char *rchallenge, const char *username, u_char authResponse[MS_AUTH_RESPONSE_LENGTH+1]) { /* * "Magic" constants used in response generation, from RFC 2759. */ static const u_char Magic1[39] = /* "Magic server to client signing constant" */ { 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 }; static const u_char Magic2[41] = /* "Pad to make it do more than one iteration" */ { 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 }; int i; lwip_sha1_context sha1Context; u_char Digest[SHA1_SIGNATURE_SIZE]; u_char Challenge[8]; lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, PasswordHashHash, MD4_SIGNATURE_SIZE); lwip_sha1_update(&sha1Context, NTResponse, 24); lwip_sha1_update(&sha1Context, Magic1, sizeof(Magic1)); lwip_sha1_finish(&sha1Context, Digest); lwip_sha1_free(&sha1Context); ChallengeHash(PeerChallenge, rchallenge, username, Challenge); lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, Digest, sizeof(Digest)); lwip_sha1_update(&sha1Context, Challenge, sizeof(Challenge)); lwip_sha1_update(&sha1Context, Magic2, sizeof(Magic2)); lwip_sha1_finish(&sha1Context, Digest); lwip_sha1_free(&sha1Context); /* Convert to ASCII hex string. */ for (i = 0; i < LWIP_MAX((MS_AUTH_RESPONSE_LENGTH / 2), (int)sizeof(Digest)); i++) sprintf((char *)&authResponse[i * 2], "%02X", Digest[i]); } static void GenerateAuthenticatorResponsePlain( const char *secret, int secret_len, u_char NTResponse[24], const u_char PeerChallenge[16], const u_char *rchallenge, const char *username, u_char authResponse[MS_AUTH_RESPONSE_LENGTH+1]) { u_char unicodePassword[MAX_NT_PASSWORD * 2]; u_char PasswordHash[MD4_SIGNATURE_SIZE]; u_char PasswordHashHash[MD4_SIGNATURE_SIZE]; /* Hash (x2) the Unicode version of the secret (== password). */ ascii2unicode(secret, secret_len, unicodePassword); NTPasswordHash(unicodePassword, secret_len * 2, PasswordHash); NTPasswordHash(PasswordHash, sizeof(PasswordHash), PasswordHashHash); GenerateAuthenticatorResponse(PasswordHashHash, NTResponse, PeerChallenge, rchallenge, username, authResponse); } #if MPPE_SUPPORT /* * Set mppe_xxxx_key from MS-CHAP credentials. (see RFC 3079) */ static void Set_Start_Key(ppp_pcb *pcb, const u_char *rchallenge, const char *secret, int secret_len) { u_char unicodePassword[MAX_NT_PASSWORD * 2]; u_char PasswordHash[MD4_SIGNATURE_SIZE]; u_char PasswordHashHash[MD4_SIGNATURE_SIZE]; lwip_sha1_context sha1Context; u_char Digest[SHA1_SIGNATURE_SIZE]; /* >= MPPE_MAX_KEY_LEN */ /* Hash (x2) the Unicode version of the secret (== password). */ ascii2unicode(secret, secret_len, unicodePassword); NTPasswordHash(unicodePassword, secret_len * 2, PasswordHash); NTPasswordHash(PasswordHash, sizeof(PasswordHash), PasswordHashHash); lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, PasswordHashHash, MD4_SIGNATURE_SIZE); lwip_sha1_update(&sha1Context, PasswordHashHash, MD4_SIGNATURE_SIZE); lwip_sha1_update(&sha1Context, rchallenge, 8); lwip_sha1_finish(&sha1Context, Digest); lwip_sha1_free(&sha1Context); /* Same key in both directions. */ mppe_set_key(pcb, &pcb->mppe_comp, Digest); mppe_set_key(pcb, &pcb->mppe_decomp, Digest); pcb->mppe_keys_set = 1; } /* * Set mppe_xxxx_key from MS-CHAPv2 credentials. (see RFC 3079) */ static void SetMasterKeys(ppp_pcb *pcb, const char *secret, int secret_len, u_char NTResponse[24], int IsServer) { u_char unicodePassword[MAX_NT_PASSWORD * 2]; u_char PasswordHash[MD4_SIGNATURE_SIZE]; u_char PasswordHashHash[MD4_SIGNATURE_SIZE]; lwip_sha1_context sha1Context; u_char MasterKey[SHA1_SIGNATURE_SIZE]; /* >= MPPE_MAX_KEY_LEN */ u_char Digest[SHA1_SIGNATURE_SIZE]; /* >= MPPE_MAX_KEY_LEN */ const u_char *s; /* "This is the MPPE Master Key" */ static const u_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 }; /* "On the client side, this is the send key; " "on the server side, it is the receive key." */ static const u_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 }; /* "On the client side, this is the receive key; " "on the server side, it is the send key." */ static const u_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 }; /* Hash (x2) the Unicode version of the secret (== password). */ ascii2unicode(secret, secret_len, unicodePassword); NTPasswordHash(unicodePassword, secret_len * 2, PasswordHash); NTPasswordHash(PasswordHash, sizeof(PasswordHash), PasswordHashHash); lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, PasswordHashHash, MD4_SIGNATURE_SIZE); lwip_sha1_update(&sha1Context, NTResponse, 24); lwip_sha1_update(&sha1Context, Magic1, sizeof(Magic1)); lwip_sha1_finish(&sha1Context, MasterKey); lwip_sha1_free(&sha1Context); /* * generate send key */ if (IsServer) s = Magic3; else s = Magic2; lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, MasterKey, 16); lwip_sha1_update(&sha1Context, mppe_sha1_pad1, SHA1_PAD_SIZE); lwip_sha1_update(&sha1Context, s, 84); lwip_sha1_update(&sha1Context, mppe_sha1_pad2, SHA1_PAD_SIZE); lwip_sha1_finish(&sha1Context, Digest); lwip_sha1_free(&sha1Context); mppe_set_key(pcb, &pcb->mppe_comp, Digest); /* * generate recv key */ if (IsServer) s = Magic2; else s = Magic3; lwip_sha1_init(&sha1Context); lwip_sha1_starts(&sha1Context); lwip_sha1_update(&sha1Context, MasterKey, 16); lwip_sha1_update(&sha1Context, mppe_sha1_pad1, SHA1_PAD_SIZE); lwip_sha1_update(&sha1Context, s, 84); lwip_sha1_update(&sha1Context, mppe_sha1_pad2, SHA1_PAD_SIZE); lwip_sha1_finish(&sha1Context, Digest); lwip_sha1_free(&sha1Context); mppe_set_key(pcb, &pcb->mppe_decomp, Digest); pcb->mppe_keys_set = 1; } #endif /* MPPE_SUPPORT */ static void ChapMS(ppp_pcb *pcb, const u_char *rchallenge, const char *secret, int secret_len, unsigned char *response) { #if !MPPE_SUPPORT LWIP_UNUSED_ARG(pcb); #endif /* !MPPE_SUPPORT */ BZERO(response, MS_CHAP_RESPONSE_LEN); ChapMS_NT(rchallenge, secret, secret_len, &response[MS_CHAP_NTRESP]); #ifdef MSLANMAN ChapMS_LANMan(rchallenge, secret, secret_len, &response[MS_CHAP_LANMANRESP]); /* preferred method is set by option */ response[MS_CHAP_USENT] = !ms_lanman; #else response[MS_CHAP_USENT] = 1; #endif #if MPPE_SUPPORT Set_Start_Key(pcb, rchallenge, secret, secret_len); #endif /* MPPE_SUPPORT */ } /* * If PeerChallenge is NULL, one is generated and the PeerChallenge * field of response is filled in. Call this way when generating a response. * If PeerChallenge is supplied, it is copied into the PeerChallenge field. * Call this way when verifying a response (or debugging). * Do not call with PeerChallenge = response. * * The PeerChallenge field of response is then used for calculation of the * Authenticator Response. */ static void ChapMS2(ppp_pcb *pcb, const u_char *rchallenge, const u_char *PeerChallenge, const char *user, const char *secret, int secret_len, unsigned char *response, u_char authResponse[], int authenticator) { /* ARGSUSED */ LWIP_UNUSED_ARG(authenticator); #if !MPPE_SUPPORT LWIP_UNUSED_ARG(pcb); #endif /* !MPPE_SUPPORT */ BZERO(response, MS_CHAP2_RESPONSE_LEN); /* Generate the Peer-Challenge if requested, or copy it if supplied. */ if (!PeerChallenge) magic_random_bytes(&response[MS_CHAP2_PEER_CHALLENGE], MS_CHAP2_PEER_CHAL_LEN); else MEMCPY(&response[MS_CHAP2_PEER_CHALLENGE], PeerChallenge, MS_CHAP2_PEER_CHAL_LEN); /* Generate the NT-Response */ ChapMS2_NT(rchallenge, &response[MS_CHAP2_PEER_CHALLENGE], user, secret, secret_len, &response[MS_CHAP2_NTRESP]); /* Generate the Authenticator Response. */ GenerateAuthenticatorResponsePlain(secret, secret_len, &response[MS_CHAP2_NTRESP], &response[MS_CHAP2_PEER_CHALLENGE], rchallenge, user, authResponse); #if MPPE_SUPPORT SetMasterKeys(pcb, secret, secret_len, &response[MS_CHAP2_NTRESP], authenticator); #endif /* MPPE_SUPPORT */ } #if 0 /* UNUSED */ #if MPPE_SUPPORT /* * Set MPPE options from plugins. */ void set_mppe_enc_types(int policy, int types) { /* Early exit for unknown policies. */ if (policy != MPPE_ENC_POL_ENC_ALLOWED || policy != MPPE_ENC_POL_ENC_REQUIRED) return; /* Don't modify MPPE if it's optional and wasn't already configured. */ if (policy == MPPE_ENC_POL_ENC_ALLOWED && !ccp_wantoptions[0].mppe) return; /* * Disable undesirable encryption types. Note that we don't ENABLE * any encryption types, to avoid overriding manual configuration. */ switch(types) { case MPPE_ENC_TYPES_RC4_40: ccp_wantoptions[0].mppe &= ~MPPE_OPT_128; /* disable 128-bit */ break; case MPPE_ENC_TYPES_RC4_128: ccp_wantoptions[0].mppe &= ~MPPE_OPT_40; /* disable 40-bit */ break; default: break; } } #endif /* MPPE_SUPPORT */ #endif /* UNUSED */ const struct chap_digest_type chapms_digest = { CHAP_MICROSOFT, /* code */ #if PPP_SERVER chapms_generate_challenge, chapms_verify_response, #endif /* PPP_SERVER */ chapms_make_response, NULL, /* check_success */ chapms_handle_failure, }; const struct chap_digest_type chapms2_digest = { CHAP_MICROSOFT_V2, /* code */ #if PPP_SERVER chapms2_generate_challenge, chapms2_verify_response, #endif /* PPP_SERVER */ chapms2_make_response, chapms2_check_success, chapms_handle_failure, }; #endif /* PPP_SUPPORT && MSCHAP_SUPPORT */