ntlmssp_sign.c

samba最新软件

 * Unseal data with the NTLMSSP algorithm
 *
 */

/*
  wrappers for the ntlmssp_*() functions
*/
NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security, 
				      TALLOC_CTX *sig_mem_ctx, 
				      uint8_t *data, size_t length, 
				      const uint8_t *whole_pdu, size_t pdu_length, 
				      const DATA_BLOB *sig)
{
	struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
	if (!gensec_ntlmssp_state->session_key.length) {
		DEBUG(3, ("NO session key, cannot unseal packet\n"));
		return NT_STATUS_NO_USER_SESSION_KEY;
	}

	dump_data_pw("ntlmssp sealed data\n", data, length);
	if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
		arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
	} else {
		arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
	}
	dump_data_pw("ntlmssp clear data\n", data, length);
	return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
}

/**
   Initialise the state for NTLMSSP signing.
*/
/* TODO: make this non-public */
NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
{
	TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);

	if (!mem_ctx) {
		return NT_STATUS_NO_MEMORY;
	}

	DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
	debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);

	if (gensec_ntlmssp_state->session_key.length < 8) {
		talloc_free(mem_ctx);
		DEBUG(3, ("NO session key, cannot intialise signing\n"));
		return NT_STATUS_NO_USER_SESSION_KEY;
	}

	if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
	{
		DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
		const char *send_sign_const;
		const char *send_seal_const;
		const char *recv_sign_const;
		const char *recv_seal_const;

		DATA_BLOB send_seal_key;
		DATA_BLOB recv_seal_key;

		switch (gensec_ntlmssp_state->role) {
		case NTLMSSP_CLIENT:
			send_sign_const = CLI_SIGN;
			send_seal_const = CLI_SEAL;
			recv_sign_const = SRV_SIGN;
			recv_seal_const = SRV_SEAL;
			break;
		case NTLMSSP_SERVER:
			send_sign_const = SRV_SIGN;
			send_seal_const = SRV_SEAL;
			recv_sign_const = CLI_SIGN;
			recv_seal_const = CLI_SEAL;
			break;
		default:
			talloc_free(mem_ctx);
			return NT_STATUS_INTERNAL_ERROR;
		}
		
		gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
		NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
		gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
		NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);

		/**
		   Weaken NTLMSSP keys to cope with down-level
		   clients, servers and export restrictions.
		   
		   We probably should have some parameters to control
		   this, once we get NTLM2 working.
		*/

		/* Key weakening was not performed on the master key
		 * for NTLM2 (in ntlmssp_weaken_keys()), but must be
		 * done on the encryption subkeys only.  That is why
		 * we don't have this code for the ntlmv1 case.
		 */

		if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
			
		} else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
			weak_session_key.length = 7;
		} else { /* forty bits */
			weak_session_key.length = 5;
		}
		dump_data_pw("NTLMSSP weakend master key:\n",
			     weak_session_key.data, 
			     weak_session_key.length);

		/* SEND: sign key */
		calc_ntlmv2_key(gensec_ntlmssp_state, 
				&gensec_ntlmssp_state->crypt.ntlm2.send_sign_key, 
				gensec_ntlmssp_state->session_key, send_sign_const);
		dump_data_pw("NTLMSSP send sign key:\n",
			     gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data, 
			     gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
		
		/* SEND: seal ARCFOUR pad */
		calc_ntlmv2_key(mem_ctx, 
				&send_seal_key, 
				weak_session_key, send_seal_const);
		dump_data_pw("NTLMSSP send seal key:\n",
			     send_seal_key.data, 
			     send_seal_key.length);
		arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, 
			     &send_seal_key);
		dump_data_pw("NTLMSSP send sesl hash:\n", 
			     gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox, 
			     sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));

		/* RECV: sign key */
		calc_ntlmv2_key(gensec_ntlmssp_state, 
				&gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key, 
				gensec_ntlmssp_state->session_key, recv_sign_const);
		dump_data_pw("NTLMSSP recv sign key:\n",
			     gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data, 
			     gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);

		/* RECV: seal ARCFOUR pad */
		calc_ntlmv2_key(mem_ctx, 
				&recv_seal_key, 
				weak_session_key, recv_seal_const);
		dump_data_pw("NTLMSSP recv seal key:\n",
			     recv_seal_key.data, 
			     recv_seal_key.length);
		arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, 
			     &recv_seal_key);
		dump_data_pw("NTLMSSP receive seal hash:\n", 
			     gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox, 
			     sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));

		gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
		gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;

	} else {
		DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
		DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));

		gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
		NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);

		arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, 
			     &weak_session_key);
		dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
			     sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));

		gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
	}

	talloc_free(mem_ctx);
	return NT_STATUS_OK;
}

size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size) 
{
	return NTLMSSP_SIG_SIZE;
}

NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security, 
			     TALLOC_CTX *sig_mem_ctx, 
			     const DATA_BLOB *in, 
			     DATA_BLOB *out)
{
	DATA_BLOB sig;
	NTSTATUS nt_status;

	if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {

		*out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
		if (!out->data) {
			return NT_STATUS_NO_MEMORY;
		}
		memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
		
	        nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx, 
						       out->data + NTLMSSP_SIG_SIZE, 
						       out->length - NTLMSSP_SIG_SIZE, 
						       out->data + NTLMSSP_SIG_SIZE, 
						       out->length - NTLMSSP_SIG_SIZE, 
						       &sig);
		
		if (NT_STATUS_IS_OK(nt_status)) {
			memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
		}
		return nt_status;

	} else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {

		*out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
		if (!out->data) {
			return NT_STATUS_NO_MEMORY;
		}
		memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);

	        nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx, 
						       out->data + NTLMSSP_SIG_SIZE, 
						       out->length - NTLMSSP_SIG_SIZE, 
						       out->data + NTLMSSP_SIG_SIZE, 
						       out->length - NTLMSSP_SIG_SIZE, 
						       &sig);

		if (NT_STATUS_IS_OK(nt_status)) {
			memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
		}
		return nt_status;

	} else {
		*out = *in;
		return NT_STATUS_OK;
	}
}


NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security, 
			       TALLOC_CTX *sig_mem_ctx, 
			       const DATA_BLOB *in, 
			       DATA_BLOB *out)
{
	DATA_BLOB sig;

	if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
		if (in->length < NTLMSSP_SIG_SIZE) {
			return NT_STATUS_INVALID_PARAMETER;
		}
		sig.data = in->data;
		sig.length = NTLMSSP_SIG_SIZE;

		*out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
		
	        return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx, 
						    out->data, out->length, 
						    out->data, out->length, 
						    &sig);
						  
	} else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
		if (in->length < NTLMSSP_SIG_SIZE) {
			return NT_STATUS_INVALID_PARAMETER;
		}
		sig.data = in->data;
		sig.length = NTLMSSP_SIG_SIZE;

		*out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
		
	        return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, 
						   out->data, out->length, 
						   out->data, out->length, 
						   &sig);
	} else {
		*out = *in;
		return NT_STATUS_OK;
	}
}