/* * WPA Supplicant / shared MSCHAPV2 helper functions / RFC 2433 / RFC 2759 * Copyright (c) 2004-2012, Jouni Malinen * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "utils/includes.h" #include "utils/common.h" #include "crypto/sha1.h" #include "crypto/ms_funcs.h" #include "crypto/crypto.h" /** * utf8_to_ucs2 - Convert UTF-8 string to UCS-2 encoding * @utf8_string: UTF-8 string (IN) * @utf8_string_len: Length of utf8_string (IN) * @ucs2_buffer: UCS-2 buffer (OUT) * @ucs2_buffer_size: Length of UCS-2 buffer (IN) * @ucs2_string_size: Number of 2-byte words in the resulting UCS-2 string * Returns: 0 on success, -1 on failure */ static int utf8_to_ucs2(const u8 *utf8_string, size_t utf8_string_len, u8 *ucs2_buffer, size_t ucs2_buffer_size, size_t *ucs2_string_size) { size_t i, j; for (i = 0, j = 0; i < utf8_string_len; i++) { u8 c = utf8_string[i]; if (j >= ucs2_buffer_size) { /* input too long */ return -1; } if (c <= 0x7F) { WPA_PUT_LE16(ucs2_buffer + j, c); j += 2; } else if (i == utf8_string_len - 1 || j >= ucs2_buffer_size - 1) { /* incomplete surrogate */ return -1; } else { u8 c2 = utf8_string[++i]; if ((c & 0xE0) == 0xC0) { /* two-byte encoding */ WPA_PUT_LE16(ucs2_buffer + j, ((c & 0x1F) << 6) | (c2 & 0x3F)); j += 2; } else if (i == utf8_string_len || j >= ucs2_buffer_size - 1) { /* incomplete surrogate */ return -1; } else { /* three-byte encoding */ u8 c3 = utf8_string[++i]; WPA_PUT_LE16(ucs2_buffer + j, ((c & 0xF) << 12) | ((c2 & 0x3F) << 6) | (c3 & 0x3F)); } } } if (ucs2_string_size) *ucs2_string_size = j / 2; return 0; } /** * challenge_hash - ChallengeHash() - RFC 2759, Sect. 8.2 * @peer_challenge: 16-octet PeerChallenge (IN) * @auth_challenge: 16-octet AuthenticatorChallenge (IN) * @username: 0-to-256-char UserName (IN) * @username_len: Length of username * @challenge: 8-octet Challenge (OUT) * Returns: 0 on success, -1 on failure */ static int challenge_hash(const u8 *peer_challenge, const u8 *auth_challenge, const u8 *username, size_t username_len, u8 *challenge) { u8 hash[SHA1_MAC_LEN]; const unsigned char *addr[3]; size_t len[3]; addr[0] = peer_challenge; len[0] = 16; addr[1] = auth_challenge; len[1] = 16; addr[2] = username; len[2] = username_len; if (sha1_vector(3, addr, len, hash)) return -1; os_memcpy(challenge, hash, 8); return 0; } /** * nt_password_hash - NtPasswordHash() - RFC 2759, Sect. 8.3 * @password: 0-to-256-unicode-char Password (IN; UTF-8) * @password_len: Length of password * @password_hash: 16-octet PasswordHash (OUT) * Returns: 0 on success, -1 on failure */ int nt_password_hash(const u8 *password, size_t password_len, u8 *password_hash) { u8 buf[512], *pos; size_t len, max_len; max_len = sizeof(buf); if (utf8_to_ucs2(password, password_len, buf, max_len, &len) < 0) return -1; len *= 2; pos = buf; return md4_vector(1, (const u8 **) &pos, &len, password_hash); } /** * hash_nt_password_hash - HashNtPasswordHash() - RFC 2759, Sect. 8.4 * @password_hash: 16-octet PasswordHash (IN) * @password_hash_hash: 16-octet PasswordHashHash (OUT) * Returns: 0 on success, -1 on failure */ int hash_nt_password_hash(const u8 *password_hash, u8 *password_hash_hash) { size_t len = 16; return md4_vector(1, &password_hash, &len, password_hash_hash); } /** * challenge_response - ChallengeResponse() - RFC 2759, Sect. 8.5 * @challenge: 8-octet Challenge (IN) * @password_hash: 16-octet PasswordHash (IN) * @response: 24-octet Response (OUT) */ void challenge_response(const u8 *challenge, const u8 *password_hash, u8 *response) { u8 zpwd[7]; des_encrypt(challenge, password_hash, response); des_encrypt(challenge, password_hash + 7, response + 8); zpwd[0] = password_hash[14]; zpwd[1] = password_hash[15]; os_memset(zpwd + 2, 0, 5); des_encrypt(challenge, zpwd, response + 16); } /** * generate_nt_response - GenerateNTResponse() - RFC 2759, Sect. 8.1 * @auth_challenge: 16-octet AuthenticatorChallenge (IN) * @peer_challenge: 16-octet PeerChallenge (IN) * @username: 0-to-256-char UserName (IN) * @username_len: Length of username * @password: 0-to-256-unicode-char Password (IN; UTF-8) * @password_len: Length of password * @response: 24-octet Response (OUT) * Returns: 0 on success, -1 on failure */ int generate_nt_response(const u8 *auth_challenge, const u8 *peer_challenge, const u8 *username, size_t username_len, const u8 *password, size_t password_len, u8 *response) { u8 challenge[8]; u8 password_hash[16]; if (challenge_hash(peer_challenge, auth_challenge, username, username_len, challenge)) return -1; if (nt_password_hash(password, password_len, password_hash)) return -1; challenge_response(challenge, password_hash, response); return 0; } /** * generate_nt_response_pwhash - GenerateNTResponse() - RFC 2759, Sect. 8.1 * @auth_challenge: 16-octet AuthenticatorChallenge (IN) * @peer_challenge: 16-octet PeerChallenge (IN) * @username: 0-to-256-char UserName (IN) * @username_len: Length of username * @password_hash: 16-octet PasswordHash (IN) * @response: 24-octet Response (OUT) * Returns: 0 on success, -1 on failure */ int generate_nt_response_pwhash(const u8 *auth_challenge, const u8 *peer_challenge, const u8 *username, size_t username_len, const u8 *password_hash, u8 *response) { u8 challenge[8]; if (challenge_hash(peer_challenge, auth_challenge, username, username_len, challenge)) return -1; challenge_response(challenge, password_hash, response); return 0; } /** * generate_authenticator_response_pwhash - GenerateAuthenticatorResponse() - RFC 2759, Sect. 8.7 * @password_hash: 16-octet PasswordHash (IN) * @nt_response: 24-octet NT-Response (IN) * @peer_challenge: 16-octet PeerChallenge (IN) * @auth_challenge: 16-octet AuthenticatorChallenge (IN) * @username: 0-to-256-char UserName (IN) * @username_len: Length of username * @response: 20-octet AuthenticatorResponse (OUT) (note: this value is usually * encoded as a 42-octet ASCII string (S=hexdump_of_response) * Returns: 0 on success, -1 on failure */ int generate_authenticator_response_pwhash( const u8 *password_hash, const u8 *peer_challenge, const u8 *auth_challenge, const u8 *username, size_t username_len, const u8 *nt_response, u8 *response) { static const u8 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 }; static const u8 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 }; u8 password_hash_hash[16], challenge[8]; const unsigned char *addr1[3]; const size_t len1[3] = { 16, 24, sizeof(magic1) }; const unsigned char *addr2[3]; const size_t len2[3] = { SHA1_MAC_LEN, 8, sizeof(magic2) }; addr1[0] = password_hash_hash; addr1[1] = nt_response; addr1[2] = magic1; addr2[0] = response; addr2[1] = challenge; addr2[2] = magic2; if (hash_nt_password_hash(password_hash, password_hash_hash)) return -1; if (sha1_vector(3, addr1, len1, response)) return -1; if (challenge_hash(peer_challenge, auth_challenge, username, username_len, challenge)) return -1; return sha1_vector(3, addr2, len2, response); } /** * generate_authenticator_response - GenerateAuthenticatorResponse() - RFC 2759, Sect. 8.7 * @password: 0-to-256-unicode-char Password (IN; UTF-8) * @password_len: Length of password * @nt_response: 24-octet NT-Response (IN) * @peer_challenge: 16-octet PeerChallenge (IN) * @auth_challenge: 16-octet AuthenticatorChallenge (IN) * @username: 0-to-256-char UserName (IN) * @username_len: Length of username * @response: 20-octet AuthenticatorResponse (OUT) (note: this value is usually * encoded as a 42-octet ASCII string (S=hexdump_of_response) * Returns: 0 on success, -1 on failure */ int generate_authenticator_response(const u8 *password, size_t password_len, const u8 *peer_challenge, const u8 *auth_challenge, const u8 *username, size_t username_len, const u8 *nt_response, u8 *response) { u8 password_hash[16]; if (nt_password_hash(password, password_len, password_hash)) return -1; return generate_authenticator_response_pwhash( password_hash, peer_challenge, auth_challenge, username, username_len, nt_response, response); } /** * nt_challenge_response - NtChallengeResponse() - RFC 2433, Sect. A.5 * @challenge: 8-octet Challenge (IN) * @password: 0-to-256-unicode-char Password (IN; UTF-8) * @password_len: Length of password * @response: 24-octet Response (OUT) * Returns: 0 on success, -1 on failure */ int nt_challenge_response(const u8 *challenge, const u8 *password, size_t password_len, u8 *response) { u8 password_hash[16]; if (nt_password_hash(password, password_len, password_hash)) return -1; challenge_response(challenge, password_hash, response); return 0; } /** * get_master_key - GetMasterKey() - RFC 3079, Sect. 3.4 * @password_hash_hash: 16-octet PasswordHashHash (IN) * @nt_response: 24-octet NTResponse (IN) * @master_key: 16-octet MasterKey (OUT) * Returns: 0 on success, -1 on failure */ int get_master_key(const u8 *password_hash_hash, const u8 *nt_response, u8 *master_key) { static const u8 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 }; const unsigned char *addr[3]; const size_t len[3] = { 16, 24, sizeof(magic1) }; u8 hash[SHA1_MAC_LEN]; addr[0] = password_hash_hash; addr[1] = nt_response; addr[2] = magic1; if (sha1_vector(3, addr, len, hash)) return -1; os_memcpy(master_key, hash, 16); return 0; } /** * get_asymetric_start_key - GetAsymetricStartKey() - RFC 3079, Sect. 3.4 * @master_key: 16-octet MasterKey (IN) * @session_key: 8-to-16 octet SessionKey (OUT) * @session_key_len: SessionKeyLength (Length of session_key) (IN) * @is_send: IsSend (IN, BOOLEAN) * @is_server: IsServer (IN, BOOLEAN) * Returns: 0 on success, -1 on failure */ int get_asymetric_start_key(const u8 *master_key, u8 *session_key, size_t session_key_len, int is_send, int is_server) { static const u8 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 const u8 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 }; static const u8 shs_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 const u8 shs_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 }; u8 digest[SHA1_MAC_LEN]; const unsigned char *addr[4]; const size_t len[4] = { 16, 40, 84, 40 }; addr[0] = master_key; addr[1] = shs_pad1; if (is_send) { addr[2] = is_server ? magic3 : magic2; } else { addr[2] = is_server ? magic2 : magic3; } addr[3] = shs_pad2; if (sha1_vector(4, addr, len, digest)) return -1; if (session_key_len > SHA1_MAC_LEN) session_key_len = SHA1_MAC_LEN; os_memcpy(session_key, digest, session_key_len); return 0; } #define PWBLOCK_LEN 516 /** * encrypt_pw_block_with_password_hash - EncryptPwBlockWithPasswordHash() - RFC 2759, Sect. 8.10 * @password: 0-to-256-unicode-char Password (IN; UTF-8) * @password_len: Length of password * @password_hash: 16-octet PasswordHash (IN) * @pw_block: 516-byte PwBlock (OUT) * Returns: 0 on success, -1 on failure */ int encrypt_pw_block_with_password_hash( const u8 *password, size_t password_len, const u8 *password_hash, u8 *pw_block) { size_t ucs2_len, offset; u8 *pos; os_memset(pw_block, 0, PWBLOCK_LEN); if (utf8_to_ucs2(password, password_len, pw_block, 512, &ucs2_len) < 0) return -1; if (ucs2_len > 256) return -1; offset = (256 - ucs2_len) * 2; if (offset != 0) { os_memmove(pw_block + offset, pw_block, ucs2_len * 2); if (os_get_random(pw_block, offset) < 0) return -1; } /* * PasswordLength is 4 octets, but since the maximum password length is * 256, only first two (in little endian byte order) can be non-zero. */ pos = &pw_block[2 * 256]; WPA_PUT_LE16(pos, password_len * 2); rc4_skip(password_hash, 16, 0, pw_block, PWBLOCK_LEN); return 0; } /** * new_password_encrypted_with_old_nt_password_hash - NewPasswordEncryptedWithOldNtPasswordHash() - RFC 2759, Sect. 8.9 * @new_password: 0-to-256-unicode-char NewPassword (IN; UTF-8) * @new_password_len: Length of new_password * @old_password: 0-to-256-unicode-char OldPassword (IN; UTF-8) * @old_password_len: Length of old_password * @encrypted_pw_block: 516-octet EncryptedPwBlock (OUT) * Returns: 0 on success, -1 on failure */ int new_password_encrypted_with_old_nt_password_hash( const u8 *new_password, size_t new_password_len, const u8 *old_password, size_t old_password_len, u8 *encrypted_pw_block) { u8 password_hash[16]; if (nt_password_hash(old_password, old_password_len, password_hash)) return -1; if (encrypt_pw_block_with_password_hash(new_password, new_password_len, password_hash, encrypted_pw_block)) return -1; return 0; } /** * nt_password_hash_encrypted_with_block - NtPasswordHashEncryptedWithBlock() - RFC 2759, Sect 8.13 * @password_hash: 16-octer PasswordHash (IN) * @block: 16-octet Block (IN) * @cypher: 16-octer Cypher (OUT) */ void nt_password_hash_encrypted_with_block(const u8 *password_hash, const u8 *block, u8 *cypher) { des_encrypt(password_hash, block, cypher); des_encrypt(password_hash + 8, block + 7, cypher + 8); } /** * old_nt_password_hash_encrypted_with_new_nt_password_hash - OldNtPasswordHashEncryptedWithNewNtPasswordHash() - RFC 2759, Sect. 8.12 * @new_password: 0-to-256-unicode-char NewPassword (IN; UTF-8) * @new_password_len: Length of new_password * @old_password: 0-to-256-unicode-char OldPassword (IN; UTF-8) * @old_password_len: Length of old_password * @encrypted_password_hash: 16-octet EncryptedPasswordHash (OUT) * Returns: 0 on success, -1 on failure */ int old_nt_password_hash_encrypted_with_new_nt_password_hash( const u8 *new_password, size_t new_password_len, const u8 *old_password, size_t old_password_len, u8 *encrypted_password_hash) { u8 old_password_hash[16], new_password_hash[16]; if (nt_password_hash(old_password, old_password_len, old_password_hash) || nt_password_hash(new_password, new_password_len, new_password_hash)) return -1; nt_password_hash_encrypted_with_block(old_password_hash, new_password_hash, encrypted_password_hash); return 0; }