(merge from 3.0)

[Samba/gebeck_regimport.git] / source / libsmb / smbencrypt.c

/* 
   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 */
void SMBencrypt(const char *passwd, const uchar *c8, uchar p24[24])
{
        uchar p21[21];

        memset(p21,'\0',21);
        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
}

/**
 * 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, uchar 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);

        mdfour(p16, (unsigned char *)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, uchar 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 unsigned char *)dospwd, p16);

        if (strlen(dospwd) > 14) {
                ret = False;
        }

        ZERO_STRUCT(dospwd);    

        return ret;
}

/**
 * Creates the MD4 and DES (LM) Hash of the users password.  
 * MD4 is of the NT Unicode, DES is of the DOS UPPERCASE password.
 * @param passwd password in 'unix' charset.
 * @param nt_p16 return password hashed with md4, caller allocated 16 byte buffer
 * @param p16 return password hashed with des, caller allocated 16 byte buffer
 */
 
/* Does both the NT and LM owfs of a user's password */
void nt_lm_owf_gen(const char *pwd, uchar nt_p16[16], uchar p16[16])
{
        /* Calculate the MD4 hash (NT compatible) of the password */
        memset(nt_p16, '\0', 16);
        E_md4hash(pwd, nt_p16);

#ifdef DEBUG_PASSWORD
        DEBUG(100,("nt_lm_owf_gen: pwd, nt#\n"));
        dump_data(120, pwd, strlen(pwd));
        dump_data(100, (char *)nt_p16, 16);
#endif

        E_deshash(pwd, (uchar *)p16);

#ifdef DEBUG_PASSWORD
        DEBUG(100,("nt_lm_owf_gen: pwd, lm#\n"));
        dump_data(120, pwd, strlen(pwd));
        dump_data(100, (char *)p16, 16);
#endif
}

/* Does both the NTLMv2 owfs of a user's password */
BOOL ntv2_owf_gen(const uchar owf[16],
                  const char *user_in, const char *domain_in, uchar 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);
        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 unsigned char *)user, user_byte_len, &ctx);
        hmac_md5_update((const unsigned char *)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 uchar passwd[16], const uchar *c8, uchar p24[24])
{
        uchar p21[21];

        ZERO_STRUCT(p21);
 
        memcpy(p21, passwd, 16);    
        E_P24(p21, c8, p24);
}

/* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
void NTLMSSPOWFencrypt(const uchar passwd[8], const uchar *ntlmchalresp, uchar p24[24])
{
        uchar p21[21];
 
        memset(p21,'\0',21);
        memcpy(p21, passwd, 8);    
        memset(p21 + 8, 0xbd, 8);    

        E_P24(p21, ntlmchalresp, p24);
#ifdef DEBUG_PASSWORD
        DEBUG(100,("NTLMSSPOWFencrypt: p21, c8, p24\n"));
        dump_data(100, (char *)p21, 21);
        dump_data(100, (const char *)ntlmchalresp, 8);
        dump_data(100, (char *)p24, 24);
#endif
}


/* Does the NT MD4 hash then des encryption. */
 
void SMBNTencrypt(const char *passwd, uchar *c8, uchar *p24)
{
        uchar 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
}

BOOL make_oem_passwd_hash(char data[516], const char *passwd, uchar old_pw_hash[16], BOOL unicode)
{
        encode_pw_buffer(data, passwd, (unicode?STR_UNICODE:STR_ASCII));

#ifdef DEBUG_PASSWORD
        DEBUG(100,("make_oem_passwd_hash\n"));
        dump_data(100, data, 516);
#endif
        SamOEMhash( (unsigned char *)data, (unsigned char *)old_pw_hash, 516);

        return True;
}

/* Does the md5 encryption from the Key Response for NTLMv2. */
void SMBOWFencrypt_ntv2(const uchar kr[16],
                        const DATA_BLOB *srv_chal,
                        const DATA_BLOB *cli_chal,
                        uchar 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 uchar kr[16],
                        const uchar * nt_resp, uint8 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((unsigned char *)sess_key, &ctx);

#ifdef DEBUG_PASSWORD
        DEBUG(100, ("SMBsesskeygen_ntv2:\n"));
        dump_data(100, sess_key, 16);
#endif
}

void SMBsesskeygen_ntv1(const uchar kr[16],
                        const uchar * nt_resp, uint8 sess_key[16])
{
        /* yes, this session key does not change - yes, this 
           is a problem - but it is 128 bits */
        
        mdfour((unsigned char *)sess_key, kr, 16);

#ifdef DEBUG_PASSWORD
        DEBUG(100, ("SMBsesskeygen_ntv1:\n"));
        dump_data(100, sess_key, 16);
#endif
}

void SMBsesskeygen_lmv1(const uchar lm_hash[16],
                        const uchar lm_resp[24], /* only uses 8 */ 
                        uint8 sess_key[16])
{
        /* Calculate the LM session key (effective length 40 bits,
           but changes with each session) */

        uchar p24[24];
        uchar partial_lm_hash[16];
        
        memcpy(partial_lm_hash, lm_hash, 8);
        memset(partial_lm_hash + 8, 0xbd, 8);    

        SMBOWFencrypt(lm_hash, lm_resp, p24);
        
        memcpy(sess_key, p24, 16);
        sess_key[5] = 0xe5;
        sess_key[6] = 0x38;
        sess_key[7] = 0xb0;

#ifdef DEBUG_PASSWORD
        DEBUG(100, ("SMBsesskeygen_lmv1:\n"));
        dump_data(100, sess_key, 16);
#endif
}

void SMBsesskeygen_lm_sess_key(const uchar lm_hash[16],
                        const uchar lm_resp[24], /* only uses 8 */ 
                        uint8 sess_key[16])
{
        uchar p24[24];
        uchar partial_lm_hash[16];
        
        memcpy(partial_lm_hash, lm_hash, 8);
        memset(partial_lm_hash + 8, 0xbd, 8);    

        SMBOWFencrypt(partial_lm_hash, lm_resp, p24);
        
        memcpy(sess_key, p24, 16);

#ifdef DEBUG_PASSWORD
        DEBUG(100, ("SMBsesskeygen_lmv1_jerry:\n"));
        dump_data(100, sess_key, 16);
#endif
}

DATA_BLOB NTLMv2_generate_names_blob(const char *hostname, 
                                     const char *domain)
{
        DATA_BLOB names_blob = data_blob(NULL, 0);
        
        msrpc_gen(&names_blob, "aaa", 
                  NTLMSSP_NAME_TYPE_DOMAIN, domain,
                  NTLMSSP_NAME_TYPE_SERVER, hostname,
                  0, "");
        return names_blob;
}

static DATA_BLOB NTLMv2_generate_client_data(const DATA_BLOB *names_blob) 
{
        uchar client_chal[8];
        DATA_BLOB response = data_blob(NULL, 0);
        char long_date[8];

        generate_random_buffer(client_chal, sizeof(client_chal), False);

        put_long_date(long_date, time(NULL));

        /* See http://www.ubiqx.org/cifs/SMB.html#SMB.8.5 */

        msrpc_gen(&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 uchar ntlm_v2_hash[16],
                                          const DATA_BLOB *server_chal,
                                          const DATA_BLOB *names_blob)
{
        uchar ntlmv2_response[16];
        DATA_BLOB ntlmv2_client_data;
        DATA_BLOB final_response;
        
        /* 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(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);

        data_blob_free(&ntlmv2_client_data);

        return final_response;
}

static DATA_BLOB LMv2_generate_response(const uchar ntlm_v2_hash[16],
                                        const DATA_BLOB *server_chal)
{
        uchar 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 *nt_session_key) 
{
        uchar nt_hash[16];
        uchar 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, ntlm_v2_hash)) {
                return False;
        }
        
        if (nt_response) {
                *nt_response = NTLMv2_generate_response(ntlm_v2_hash, server_chal,
                                                        names_blob); 
                if (nt_session_key) {
                        *nt_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, nt_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)
{
        uchar 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((unsigned char *)buffer, 512 - new_pw_len, True);

        /* 
         * 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 *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;
}