示例#1
0
static NTSTATUS smbd_smb2_auth_generic_return(struct smbXsrv_session *session,
					struct smbd_smb2_request *smb2req,
					uint8_t in_security_mode,
					struct auth_session_info *session_info,
					uint16_t *out_session_flags,
					uint64_t *out_session_id)
{
	NTSTATUS status;
	bool guest = false;
	uint8_t session_key[16];
	struct smbXsrv_session *x = session;
	struct smbXsrv_connection *xconn = smb2req->xconn;
	struct _derivation {
		DATA_BLOB label;
		DATA_BLOB context;
	};
	struct {
		struct _derivation signing;
		struct _derivation encryption;
		struct _derivation decryption;
		struct _derivation application;
	} derivation = { };

	if (xconn->protocol >= PROTOCOL_SMB3_10) {
		struct smbXsrv_preauth *preauth;
		struct _derivation *d;
		DATA_BLOB p;
		struct hc_sha512state sctx;
		size_t i;

		preauth = talloc_move(smb2req, &session->preauth);

		samba_SHA512_Init(&sctx);
		samba_SHA512_Update(&sctx, preauth->sha512_value,
				    sizeof(preauth->sha512_value));
		for (i = 1; i < smb2req->in.vector_count; i++) {
			samba_SHA512_Update(&sctx,
					    smb2req->in.vector[i].iov_base,
					    smb2req->in.vector[i].iov_len);
		}
		samba_SHA512_Final(preauth->sha512_value, &sctx);

		p = data_blob_const(preauth->sha512_value,
				    sizeof(preauth->sha512_value));

		d = &derivation.signing;
		d->label = data_blob_string_const_null("SMBSigningKey");
		d->context = p;

		d = &derivation.decryption;
		d->label = data_blob_string_const_null("SMBC2SCipherKey");
		d->context = p;

		d = &derivation.encryption;
		d->label = data_blob_string_const_null("SMBS2CCipherKey");
		d->context = p;

		d = &derivation.application;
		d->label = data_blob_string_const_null("SMBAppKey");
		d->context = p;

	} else if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d;

		d = &derivation.signing;
		d->label = data_blob_string_const_null("SMB2AESCMAC");
		d->context = data_blob_string_const_null("SmbSign");

		d = &derivation.decryption;
		d->label = data_blob_string_const_null("SMB2AESCCM");
		d->context = data_blob_string_const_null("ServerIn ");

		d = &derivation.encryption;
		d->label = data_blob_string_const_null("SMB2AESCCM");
		d->context = data_blob_string_const_null("ServerOut");

		d = &derivation.application;
		d->label = data_blob_string_const_null("SMB2APP");
		d->context = data_blob_string_const_null("SmbRpc");
	}

	if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
	    (xconn->smb2.server.security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED))
	{
		x->global->signing_required = true;
	}

	if ((lp_smb_encrypt(-1) >= SMB_SIGNING_DESIRED) &&
	    (xconn->smb2.client.capabilities & SMB2_CAP_ENCRYPTION)) {
		x->encryption_desired = true;
	}

	if (lp_smb_encrypt(-1) == SMB_SIGNING_REQUIRED) {
		x->encryption_desired = true;
		x->global->encryption_required = true;
	}

	if (security_session_user_level(session_info, NULL) < SECURITY_USER) {
		/* we map anonymous to guest internally */
		*out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
		*out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
		/* force no signing */
		x->global->signing_required = false;
		guest = true;
	}

	if (guest && x->global->encryption_required) {
		DEBUG(1,("reject guest session as encryption is required\n"));
		return NT_STATUS_ACCESS_DENIED;
	}

	if (xconn->smb2.server.cipher == 0) {
		if (x->global->encryption_required) {
			DEBUG(1,("reject session with dialect[0x%04X] "
				 "as encryption is required\n",
				 xconn->smb2.server.dialect));
			return NT_STATUS_ACCESS_DENIED;
		}
	}

	if (x->encryption_desired) {
		*out_session_flags |= SMB2_SESSION_FLAG_ENCRYPT_DATA;
	}

	ZERO_STRUCT(session_key);
	memcpy(session_key, session_info->session_key.data,
	       MIN(session_info->session_key.length, sizeof(session_key)));

	x->global->signing_key = data_blob_talloc(x->global,
						  session_key,
						  sizeof(session_key));
	if (x->global->signing_key.data == NULL) {
		ZERO_STRUCT(session_key);
		return NT_STATUS_NO_MEMORY;
	}

	if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d = &derivation.signing;

		smb2_key_derivation(session_key, sizeof(session_key),
				    d->label.data, d->label.length,
				    d->context.data, d->context.length,
				    x->global->signing_key.data);
	}

	if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d = &derivation.decryption;

		x->global->decryption_key = data_blob_talloc(x->global,
							     session_key,
							     sizeof(session_key));
		if (x->global->decryption_key.data == NULL) {
			ZERO_STRUCT(session_key);
			return NT_STATUS_NO_MEMORY;
		}

		smb2_key_derivation(session_key, sizeof(session_key),
				    d->label.data, d->label.length,
				    d->context.data, d->context.length,
				    x->global->decryption_key.data);
	}

	if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d = &derivation.encryption;
		size_t nonce_size;

		x->global->encryption_key = data_blob_talloc(x->global,
							     session_key,
							     sizeof(session_key));
		if (x->global->encryption_key.data == NULL) {
			ZERO_STRUCT(session_key);
			return NT_STATUS_NO_MEMORY;
		}

		smb2_key_derivation(session_key, sizeof(session_key),
				    d->label.data, d->label.length,
				    d->context.data, d->context.length,
				    x->global->encryption_key.data);

		/*
		 * CCM and GCM algorithms must never have their
		 * nonce wrap, or the security of the whole
		 * communication and the keys is destroyed.
		 * We must drop the connection once we have
		 * transfered too much data.
		 *
		 * NOTE: We assume nonces greater than 8 bytes.
		 */
		generate_random_buffer((uint8_t *)&x->nonce_high_random,
				       sizeof(x->nonce_high_random));
		switch (xconn->smb2.server.cipher) {
		case SMB2_ENCRYPTION_AES128_CCM:
			nonce_size = AES_CCM_128_NONCE_SIZE;
			break;
		case SMB2_ENCRYPTION_AES128_GCM:
			nonce_size = AES_GCM_128_IV_SIZE;
			break;
		default:
			nonce_size = 0;
			break;
		}
		x->nonce_high_max = SMB2_NONCE_HIGH_MAX(nonce_size);
		x->nonce_high = 0;
		x->nonce_low = 0;
	}

	x->global->application_key = data_blob_dup_talloc(x->global,
						x->global->signing_key);
	if (x->global->application_key.data == NULL) {
		ZERO_STRUCT(session_key);
		return NT_STATUS_NO_MEMORY;
	}

	if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d = &derivation.application;

		smb2_key_derivation(session_key, sizeof(session_key),
				    d->label.data, d->label.length,
				    d->context.data, d->context.length,
				    x->global->application_key.data);
	}
	ZERO_STRUCT(session_key);

	x->global->channels[0].signing_key = data_blob_dup_talloc(x->global->channels,
						x->global->signing_key);
	if (x->global->channels[0].signing_key.data == NULL) {
		return NT_STATUS_NO_MEMORY;
	}

	data_blob_clear_free(&session_info->session_key);
	session_info->session_key = data_blob_dup_talloc(session_info,
						x->global->application_key);
	if (session_info->session_key.data == NULL) {
		return NT_STATUS_NO_MEMORY;
	}

	session->compat = talloc_zero(session, struct user_struct);
	if (session->compat == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	session->compat->session = session;
	session->compat->homes_snum = -1;
	session->compat->session_info = session_info;
	session->compat->session_keystr = NULL;
	session->compat->vuid = session->global->session_wire_id;
	DLIST_ADD(smb2req->sconn->users, session->compat);
	smb2req->sconn->num_users++;

	if (security_session_user_level(session_info, NULL) >= SECURITY_USER) {
		session->compat->homes_snum =
			register_homes_share(session_info->unix_info->unix_name);
	}

	set_current_user_info(session_info->unix_info->sanitized_username,
			      session_info->unix_info->unix_name,
			      session_info->info->domain_name);

	reload_services(smb2req->sconn, conn_snum_used, true);

	session->status = NT_STATUS_OK;
	session->global->auth_session_info = session_info;
	session->global->auth_session_info_seqnum += 1;
	session->global->channels[0].auth_session_info_seqnum =
		session->global->auth_session_info_seqnum;
	session->global->auth_time = timeval_to_nttime(&smb2req->request_time);
	session->global->expiration_time = gensec_expire_time(session->gensec);

	if (!session_claim(session)) {
		DEBUG(1, ("smb2: Failed to claim session "
			"for vuid=%llu\n",
			(unsigned long long)session->compat->vuid));
		return NT_STATUS_LOGON_FAILURE;
	}

	status = smbXsrv_session_update(session);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0, ("smb2: Failed to update session for vuid=%llu - %s\n",
			  (unsigned long long)session->compat->vuid,
			  nt_errstr(status)));
		return NT_STATUS_LOGON_FAILURE;
	}

	/*
	 * we attach the session to the request
	 * so that the response can be signed
	 */
	if (!guest) {
		smb2req->do_signing = true;
	}

	global_client_caps |= (CAP_LEVEL_II_OPLOCKS|CAP_STATUS32);

	*out_session_id = session->global->session_wire_id;

	return NT_STATUS_OK;
}
示例#2
0
static NTSTATUS smbd_smb2_bind_auth_return(struct smbXsrv_session *session,
					   struct smbXsrv_session_auth0 **_auth,
					   struct smbd_smb2_request *smb2req,
					   struct auth_session_info *session_info,
					   uint16_t *out_session_flags,
					   uint64_t *out_session_id)
{
	NTSTATUS status;
	struct smbXsrv_session *x = session;
	struct smbXsrv_session_auth0 *auth = *_auth;
	struct smbXsrv_connection *xconn = smb2req->xconn;
	struct smbXsrv_channel_global0 *c = NULL;
	uint8_t session_key[16];
	size_t i;
	struct _derivation {
		DATA_BLOB label;
		DATA_BLOB context;
	};
	struct {
		struct _derivation signing;
	} derivation = { };
	bool ok;

	*_auth = NULL;

	if (xconn->protocol >= PROTOCOL_SMB3_10) {
		struct smbXsrv_preauth *preauth;
		struct _derivation *d;
		DATA_BLOB p;
		struct hc_sha512state sctx;

		preauth = talloc_move(smb2req, &auth->preauth);

		samba_SHA512_Init(&sctx);
		samba_SHA512_Update(&sctx, preauth->sha512_value,
				    sizeof(preauth->sha512_value));
		for (i = 1; i < smb2req->in.vector_count; i++) {
			samba_SHA512_Update(&sctx,
					    smb2req->in.vector[i].iov_base,
					    smb2req->in.vector[i].iov_len);
		}
		samba_SHA512_Final(preauth->sha512_value, &sctx);

		p = data_blob_const(preauth->sha512_value,
				    sizeof(preauth->sha512_value));

		d = &derivation.signing;
		d->label = data_blob_string_const_null("SMBSigningKey");
		d->context = p;

	} else if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d;

		d = &derivation.signing;
		d->label = data_blob_string_const_null("SMB2AESCMAC");
		d->context = data_blob_string_const_null("SmbSign");
	}

	status = smbXsrv_session_find_channel(session, xconn, &c);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	ok = security_token_is_sid(session_info->security_token,
			&x->global->auth_session_info->security_token->sids[0]);
	if (!ok) {
		return NT_STATUS_NOT_SUPPORTED;
	}

	if (session_info->session_key.length == 0) {
		/* See [MS-SMB2] 3.3.5.2.4 for the return code. */
		return NT_STATUS_NOT_SUPPORTED;
	}

	ZERO_STRUCT(session_key);
	memcpy(session_key, session_info->session_key.data,
	       MIN(session_info->session_key.length, sizeof(session_key)));

	c->signing_key = data_blob_talloc(x->global,
					  session_key,
					  sizeof(session_key));
	if (c->signing_key.data == NULL) {
		ZERO_STRUCT(session_key);
		return NT_STATUS_NO_MEMORY;
	}

	if (xconn->protocol >= PROTOCOL_SMB2_24) {
		struct _derivation *d = &derivation.signing;

		smb2_key_derivation(session_key, sizeof(session_key),
				    d->label.data, d->label.length,
				    d->context.data, d->context.length,
				    c->signing_key.data);
	}
	ZERO_STRUCT(session_key);

	TALLOC_FREE(auth);
	status = smbXsrv_session_update(session);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0, ("smb2: Failed to update session for vuid=%llu - %s\n",
			  (unsigned long long)session->compat->vuid,
			  nt_errstr(status)));
		return NT_STATUS_LOGON_FAILURE;
	}

	*out_session_id = session->global->session_wire_id;

	return NT_STATUS_OK;
}