/* Unix SMB/CIFS implementation. SMB parameters and setup Copyright (C) Andrew Tridgell 1992-1998 Modified by Jeremy Allison 1995. Copyright (C) Jeremy Allison 1995-2000. Copyright (C) Luke Kennethc Casson Leighton 1996-2000. Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "includes.h" #include "byteorder.h" /* This implements the X/Open SMB password encryption It takes a password ('unix' string), a 8 byte "crypt key" and puts 24 bytes of encrypted password into p24 Returns False if password must have been truncated to create LM hash */ BOOL SMBencrypt(const char *passwd, const uint8_t *c8, uint8_t p24[24]) { BOOL ret; uint8_t p21[21]; memset(p21,'\0',21); ret = E_deshash(passwd, p21); SMBOWFencrypt(p21, c8, p24); #ifdef DEBUG_PASSWORD DEBUG(100,("SMBencrypt: lm#, challenge, response\n")); dump_data(100, (char *)p21, 16); dump_data(100, (const char *)c8, 8); dump_data(100, (char *)p24, 24); #endif return ret; } /** * Creates the MD4 Hash of the users password in NT UNICODE. * @param passwd password in 'unix' charset. * @param p16 return password hashed with md4, caller allocated 16 byte buffer */ void E_md4hash(const char *passwd, uint8_t p16[16]) { int len; smb_ucs2_t wpwd[129]; /* Password must be converted to NT unicode - null terminated. */ push_ucs2(NULL, wpwd, (const char *)passwd, 256, STR_UNICODE|STR_NOALIGN|STR_TERMINATE); /* Calculate length in bytes */ len = strlen_w(wpwd) * sizeof(int16_t); mdfour(p16, (uint8_t *)wpwd, len); ZERO_STRUCT(wpwd); } /** * Creates the DES forward-only Hash of the users password in DOS ASCII charset * @param passwd password in 'unix' charset. * @param p16 return password hashed with DES, caller allocated 16 byte buffer * @return False if password was > 14 characters, and therefore may be incorrect, otherwise True * @note p16 is filled in regardless */ BOOL E_deshash(const char *passwd, uint8_t p16[16]) { BOOL ret = True; fstring dospwd; ZERO_STRUCT(dospwd); /* Password must be converted to DOS charset - null terminated, uppercase. */ push_ascii(dospwd, passwd, sizeof(dospwd), STR_UPPER|STR_TERMINATE); /* Only the fisrt 14 chars are considered, password need not be null terminated. */ E_P16((const uint8_t *)dospwd, p16); if (strlen(dospwd) > 14) { ret = False; } ZERO_STRUCT(dospwd); return ret; } /* Does both the NTLMv2 owfs of a user's password */ BOOL ntv2_owf_gen(const uint8_t owf[16], const char *user_in, const char *domain_in, BOOL upper_case_domain, /* Transform the domain into UPPER case */ uint8_t kr_buf[16]) { smb_ucs2_t *user; smb_ucs2_t *domain; size_t user_byte_len; size_t domain_byte_len; HMACMD5Context ctx; user_byte_len = push_ucs2_allocate(&user, user_in); if (user_byte_len == (size_t)-1) { DEBUG(0, ("push_uss2_allocate() for user returned -1 (probably malloc() failure)\n")); return False; } domain_byte_len = push_ucs2_allocate(&domain, domain_in); if (domain_byte_len == (size_t)-1) { DEBUG(0, ("push_uss2_allocate() for domain returned -1 (probably malloc() failure)\n")); return False; } strupper_w(user); if (upper_case_domain) strupper_w(domain); SMB_ASSERT(user_byte_len >= 2); SMB_ASSERT(domain_byte_len >= 2); /* We don't want null termination */ user_byte_len = user_byte_len - 2; domain_byte_len = domain_byte_len - 2; hmac_md5_init_limK_to_64(owf, 16, &ctx); hmac_md5_update((const uint8_t *)user, user_byte_len, &ctx); hmac_md5_update((const uint8_t *)domain, domain_byte_len, &ctx); hmac_md5_final(kr_buf, &ctx); #ifdef DEBUG_PASSWORD DEBUG(100, ("ntv2_owf_gen: user, domain, owfkey, kr\n")); dump_data(100, (const char *)user, user_byte_len); dump_data(100, (const char *)domain, domain_byte_len); dump_data(100, owf, 16); dump_data(100, kr_buf, 16); #endif SAFE_FREE(user); SAFE_FREE(domain); return True; } /* Does the des encryption from the NT or LM MD4 hash. */ void SMBOWFencrypt(const uint8_t passwd[16], const uint8_t *c8, uint8_t p24[24]) { uint8_t p21[21]; ZERO_STRUCT(p21); memcpy(p21, passwd, 16); E_P24(p21, c8, p24); } /* Does the NT MD4 hash then des encryption. */ void SMBNTencrypt(const char *passwd, uint8_t *c8, uint8_t *p24) { uint8_t p21[21]; memset(p21,'\0',21); E_md4hash(passwd, p21); SMBOWFencrypt(p21, c8, p24); #ifdef DEBUG_PASSWORD DEBUG(100,("SMBNTencrypt: nt#, challenge, response\n")); dump_data(100, (char *)p21, 16); dump_data(100, (char *)c8, 8); dump_data(100, (char *)p24, 24); #endif } /* Does the md5 encryption from the Key Response for NTLMv2. */ void SMBOWFencrypt_ntv2(const uint8_t kr[16], const DATA_BLOB *srv_chal, const DATA_BLOB *cli_chal, uint8_t resp_buf[16]) { HMACMD5Context ctx; hmac_md5_init_limK_to_64(kr, 16, &ctx); hmac_md5_update(srv_chal->data, srv_chal->length, &ctx); hmac_md5_update(cli_chal->data, cli_chal->length, &ctx); hmac_md5_final(resp_buf, &ctx); #ifdef DEBUG_PASSWORD DEBUG(100, ("SMBOWFencrypt_ntv2: srv_chal, cli_chal, resp_buf\n")); dump_data(100, srv_chal->data, srv_chal->length); dump_data(100, cli_chal->data, cli_chal->length); dump_data(100, resp_buf, 16); #endif } void SMBsesskeygen_ntv2(const uint8_t kr[16], const uint8_t * nt_resp, uint8_t sess_key[16]) { /* a very nice, 128 bit, variable session key */ HMACMD5Context ctx; hmac_md5_init_limK_to_64(kr, 16, &ctx); hmac_md5_update(nt_resp, 16, &ctx); hmac_md5_final((uint8_t *)sess_key, &ctx); #ifdef DEBUG_PASSWORD DEBUG(100, ("SMBsesskeygen_ntv2:\n")); dump_data(100, sess_key, 16); #endif } void SMBsesskeygen_ntv1(const uint8_t kr[16], uint8_t sess_key[16]) { /* yes, this session key does not change - yes, this is a problem - but it is 128 bits */ mdfour((uint8_t *)sess_key, kr, 16); #ifdef DEBUG_PASSWORD DEBUG(100, ("SMBsesskeygen_ntv1:\n")); dump_data(100, sess_key, 16); #endif } void SMBsesskeygen_lm_sess_key(const uint8_t lm_hash[16], const uint8_t lm_resp[24], /* only uses 8 */ uint8_t sess_key[16]) { /* Calculate the LM session key (effective length 40 bits, but changes with each session) */ uint8_t p24[24]; uint8_t p21[21]; memset(p21,'\0',21); memcpy(p21, lm_hash, 8); memset(p21 + 8, 0xbd, 8); E_P24(p21, lm_resp, p24); memcpy(sess_key, p24, 16); #ifdef DEBUG_PASSWORD DEBUG(100, ("SMBsesskeygen_lm_sess_key: \n")); dump_data(100, sess_key, 16); #endif } DATA_BLOB NTLMv2_generate_names_blob(TALLOC_CTX *mem_ctx, const char *hostname, const char *domain) { DATA_BLOB names_blob = data_blob_talloc(mem_ctx, NULL, 0); msrpc_gen(mem_ctx, &names_blob, "aaa", NTLMSSP_NAME_TYPE_DOMAIN, domain, NTLMSSP_NAME_TYPE_SERVER, hostname, 0, ""); return names_blob; } static DATA_BLOB NTLMv2_generate_client_data(TALLOC_CTX *mem_ctx, const DATA_BLOB *names_blob) { uint8_t client_chal[8]; DATA_BLOB response = data_blob(NULL, 0); char long_date[8]; NTTIME nttime; unix_to_nt_time(&nttime, time(NULL)); generate_random_buffer(client_chal, sizeof(client_chal), False); push_nttime(long_date, 0, nttime); /* See http://www.ubiqx.org/cifs/SMB.html#SMB.8.5 */ msrpc_gen(mem_ctx, &response, "ddbbdb", 0x00000101, /* Header */ 0, /* 'Reserved' */ long_date, 8, /* Timestamp */ client_chal, 8, /* client challenge */ 0, /* Unknown */ names_blob->data, names_blob->length); /* End of name list */ return response; } static DATA_BLOB NTLMv2_generate_response(const uint8_t ntlm_v2_hash[16], const DATA_BLOB *server_chal, const DATA_BLOB *names_blob) { uint8_t ntlmv2_response[16]; DATA_BLOB ntlmv2_client_data; DATA_BLOB final_response; TALLOC_CTX *mem_ctx = talloc_init("NTLMv2_generate_response internal context"); if (!mem_ctx) { return data_blob(NULL, 0); } /* NTLMv2 */ /* generate some data to pass into the response function - including the hostname and domain name of the server */ ntlmv2_client_data = NTLMv2_generate_client_data(mem_ctx, names_blob); /* Given that data, and the challenge from the server, generate a response */ SMBOWFencrypt_ntv2(ntlm_v2_hash, server_chal, &ntlmv2_client_data, ntlmv2_response); final_response = data_blob(NULL, sizeof(ntlmv2_response) + ntlmv2_client_data.length); memcpy(final_response.data, ntlmv2_response, sizeof(ntlmv2_response)); memcpy(final_response.data+sizeof(ntlmv2_response), ntlmv2_client_data.data, ntlmv2_client_data.length); talloc_destroy(mem_ctx); return final_response; } static DATA_BLOB LMv2_generate_response(const uint8_t ntlm_v2_hash[16], const DATA_BLOB *server_chal) { uint8_t lmv2_response[16]; DATA_BLOB lmv2_client_data = data_blob(NULL, 8); DATA_BLOB final_response = data_blob(NULL, 24); /* LMv2 */ /* client-supplied random data */ generate_random_buffer(lmv2_client_data.data, lmv2_client_data.length, False); /* Given that data, and the challenge from the server, generate a response */ SMBOWFencrypt_ntv2(ntlm_v2_hash, server_chal, &lmv2_client_data, lmv2_response); memcpy(final_response.data, lmv2_response, sizeof(lmv2_response)); /* after the first 16 bytes is the random data we generated above, so the server can verify us with it */ memcpy(final_response.data+sizeof(lmv2_response), lmv2_client_data.data, lmv2_client_data.length); data_blob_free(&lmv2_client_data); return final_response; } BOOL SMBNTLMv2encrypt(const char *user, const char *domain, const char *password, const DATA_BLOB *server_chal, const DATA_BLOB *names_blob, DATA_BLOB *lm_response, DATA_BLOB *nt_response, DATA_BLOB *user_session_key) { uint8_t nt_hash[16]; uint8_t ntlm_v2_hash[16]; E_md4hash(password, nt_hash); /* We don't use the NT# directly. Instead we use it mashed up with the username and domain. This prevents username swapping during the auth exchange */ if (!ntv2_owf_gen(nt_hash, user, domain, True, ntlm_v2_hash)) { return False; } if (nt_response) { *nt_response = NTLMv2_generate_response(ntlm_v2_hash, server_chal, names_blob); if (user_session_key) { *user_session_key = data_blob(NULL, 16); /* The NTLMv2 calculations also provide a session key, for signing etc later */ /* use only the first 16 bytes of nt_response for session key */ SMBsesskeygen_ntv2(ntlm_v2_hash, nt_response->data, user_session_key->data); } } /* LMv2 */ if (lm_response) { *lm_response = LMv2_generate_response(ntlm_v2_hash, server_chal); } return True; } /*********************************************************** encode a password buffer with a unicode password. The buffer is filled with random data to make it harder to attack. ************************************************************/ BOOL encode_pw_buffer(char buffer[516], const char *password, int string_flags) { uint8_t new_pw[512]; size_t new_pw_len; new_pw_len = push_string(NULL, new_pw, password, sizeof(new_pw), string_flags); memcpy(&buffer[512 - new_pw_len], new_pw, new_pw_len); generate_random_buffer((uint8_t *)buffer, 512 - new_pw_len, False); /* * The length of the new password is in the last 4 bytes of * the data buffer. */ SIVAL(buffer, 512, new_pw_len); ZERO_STRUCT(new_pw); return True; } /*********************************************************** decode a password buffer *new_pw_len is the length in bytes of the possibly mulitbyte returned password including termination. ************************************************************/ BOOL decode_pw_buffer(char in_buffer[516], char *new_pwrd, int new_pwrd_size, uint32_t *new_pw_len, int string_flags) { int byte_len=0; /* Warning !!! : This function is called from some rpc call. The password IN the buffer may be a UNICODE string. The password IN new_pwrd is an ASCII string If you reuse that code somewhere else check first. */ /* The length of the new password is in the last 4 bytes of the data buffer. */ byte_len = IVAL(in_buffer, 512); #ifdef DEBUG_PASSWORD dump_data(100, in_buffer, 516); #endif /* Password cannot be longer than the size of the password buffer */ if ( (byte_len < 0) || (byte_len > 512)) { DEBUG(0, ("decode_pw_buffer: incorrect password length (%d).\n", byte_len)); DEBUG(0, ("decode_pw_buffer: check that 'encrypt passwords = yes'\n")); return False; } /* decode into the return buffer. Buffer length supplied */ *new_pw_len = pull_string(NULL, new_pwrd, &in_buffer[512 - byte_len], new_pwrd_size, byte_len, string_flags); #ifdef DEBUG_PASSWORD DEBUG(100,("decode_pw_buffer: new_pwrd: ")); dump_data(100, (char *)new_pwrd, *new_pw_len); DEBUG(100,("multibyte len:%d\n", *new_pw_len)); DEBUG(100,("original char len:%d\n", byte_len/2)); #endif return True; }