smbencrypt.c

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#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 partial_lm_hash[14];
 
	memcpy(partial_lm_hash, lm_hash, 8);    
	memset(partial_lm_hash + 8, 0xbd, 6);

	des_crypt56(p24,   lm_resp, partial_lm_hash,     1);
	des_crypt56(p24+8, lm_resp, partial_lm_hash + 7, 1);

	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, 
				     struct smb_iconv_convenience *iconv_convenience,
				     const char *hostname, 
				     const char *domain)
{
	DATA_BLOB names_blob = data_blob_talloc(mem_ctx, NULL, 0);
	
	msrpc_gen(mem_ctx, iconv_convenience, &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);
	uint8_t long_date[8];
	NTTIME nttime;

	unix_to_nt_time(&nttime, time(NULL));

	generate_random_buffer(client_chal, sizeof(client_chal));

	push_nttime(long_date, 0, nttime);

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

	msrpc_gen(mem_ctx, NULL, &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(TALLOC_CTX *out_mem_ctx, 
					  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_named(out_mem_ctx, 0, 
					   "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_talloc(out_mem_ctx, 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_free(mem_ctx);

	return final_response;
}

static DATA_BLOB LMv2_generate_response(TALLOC_CTX *mem_ctx, 
					const uint8_t ntlm_v2_hash[16],
					const DATA_BLOB *server_chal)
{
	uint8_t lmv2_response[16];
	DATA_BLOB lmv2_client_data = data_blob_talloc(mem_ctx, NULL, 8);
	DATA_BLOB final_response = data_blob_talloc(mem_ctx, NULL,24);
	
	/* LMv2 */
	/* client-supplied random data */
	generate_random_buffer(lmv2_client_data.data, lmv2_client_data.length);	

	/* 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_hash(TALLOC_CTX *mem_ctx, 
			   const char *user, const char *domain, const uint8_t nt_hash[16],
			   const DATA_BLOB *server_chal, 
			   const DATA_BLOB *names_blob,
			   DATA_BLOB *lm_response, DATA_BLOB *nt_response, 
			   DATA_BLOB *lm_session_key, DATA_BLOB *user_session_key) 
{
	uint8_t ntlm_v2_hash[16];

	/* 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(mem_ctx, 
							ntlm_v2_hash, server_chal,
							names_blob); 
		if (user_session_key) {
			*user_session_key = data_blob_talloc(mem_ctx, 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(mem_ctx, 
						      ntlm_v2_hash, server_chal);
		if (lm_session_key) {
			*lm_session_key = data_blob_talloc(mem_ctx, NULL, 16);
			
			/* The NTLMv2 calculations also provide a session key, for signing etc later */
			/* use only the first 16 bytes of lm_response for session key */
			SMBsesskeygen_ntv2(ntlm_v2_hash, lm_response->data, lm_session_key->data);
		}
	}
	
	return true;
}

bool SMBNTLMv2encrypt(TALLOC_CTX *mem_ctx, 
		      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 *lm_session_key, DATA_BLOB *user_session_key) 
{
	uint8_t nt_hash[16];
	E_md4hash(password, nt_hash);

	return SMBNTLMv2encrypt_hash(mem_ctx, 
				     user, domain, nt_hash, server_chal, names_blob,
				     lm_response, nt_response, lm_session_key, user_session_key);
}

/***********************************************************
 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(uint8_t buffer[516], const char *password, int string_flags)
{
	uint8_t new_pw[512];
	size_t new_pw_len;

	/* the incoming buffer can be any alignment. */
	string_flags |= STR_NOALIGN;

	new_pw_len = push_string(lp_iconv_convenience(global_loadparm), new_pw,
				 password, 
				 sizeof(new_pw), string_flags);
	
	memcpy(&buffer[512 - new_pw_len], new_pw, new_pw_len);

	generate_random_buffer(buffer, 512 - new_pw_len);

	/* 
	 * 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(uint8_t in_buffer[516], char *new_pwrd,
		      int new_pwrd_size, uint32_t *new_pw_len,
		      int string_flags)
{
	int byte_len=0;

	/* the incoming buffer can be any alignment. */
	string_flags |= STR_NOALIGN;

	/*
	  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)) {
		return false;
	}

	/* decode into the return buffer.  Buffer length supplied */
 	*new_pw_len = pull_string(lp_iconv_convenience(global_loadparm), 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, (const uint8_t *)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;
}