Ejemplo n.º 1
0
/*
 * PQfn - Send a function call to the POSTGRES backend.
 *
 * See fe-exec.c for documentation.
 */
PGresult *
pqFunctionCall2(PGconn *conn, Oid fnid,
				int *result_buf, int *actual_result_len,
				int result_is_int,
				const PQArgBlock *args, int nargs)
{
	bool		needInput = false;
	ExecStatusType status = PGRES_FATAL_ERROR;
	char		id;
	int			i;

	/* PQfn already validated connection state */

	if (pqPutMsgStart('F', false, conn) < 0 ||	/* function call msg */
		pqPuts(" ", conn) < 0 ||	/* dummy string */
		pqPutInt(fnid, 4, conn) != 0 || /* function id */
		pqPutInt(nargs, 4, conn) != 0)	/* # of args */
	{
		pqHandleSendFailure(conn);
		return NULL;
	}

	for (i = 0; i < nargs; ++i)
	{							/* len.int4 + contents	   */
		if (pqPutInt(args[i].len, 4, conn))
		{
			pqHandleSendFailure(conn);
			return NULL;
		}

		if (args[i].isint)
		{
			if (pqPutInt(args[i].u.integer, 4, conn))
			{
				pqHandleSendFailure(conn);
				return NULL;
			}
		}
		else
		{
			if (pqPutnchar((char *) args[i].u.ptr, args[i].len, conn))
			{
				pqHandleSendFailure(conn);
				return NULL;
			}
		}
	}

	if (pqPutMsgEnd(conn) < 0 ||
		pqFlush(conn))
	{
		pqHandleSendFailure(conn);
		return NULL;
	}

	for (;;)
	{
		if (needInput)
		{
			/* Wait for some data to arrive (or for the channel to close) */
			if (pqWait(TRUE, FALSE, conn) ||
				pqReadData(conn) < 0)
				break;
		}

		/*
		 * Scan the message. If we run out of data, loop around to try again.
		 */
		conn->inCursor = conn->inStart;
		needInput = true;

		if (pqGetc(&id, conn))
			continue;

		/*
		 * We should see V or E response to the command, but might get N
		 * and/or A notices first. We also need to swallow the final Z before
		 * returning.
		 */
		switch (id)
		{
			case 'V':			/* function result */
				if (pqGetc(&id, conn))
					continue;
				if (id == 'G')
				{
					/* function returned nonempty value */
					if (pqGetInt(actual_result_len, 4, conn))
						continue;
					if (result_is_int)
					{
						if (pqGetInt(result_buf, 4, conn))
							continue;
					}
					else
					{
						if (pqGetnchar((char *) result_buf,
									   *actual_result_len,
									   conn))
							continue;
					}
					if (pqGetc(&id, conn))		/* get the last '0' */
						continue;
				}
				if (id == '0')
				{
					/* correctly finished function result message */
					status = PGRES_COMMAND_OK;
				}
				else
				{
					/* The backend violates the protocol. */
					printfPQExpBuffer(&conn->errorMessage,
								  libpq_gettext("protocol error: id=0x%x\n"),
									  id);
					pqSaveErrorResult(conn);
					conn->inStart = conn->inCursor;
					return pqPrepareAsyncResult(conn);
				}
				break;
			case 'E':			/* error return */
				if (pqGetErrorNotice2(conn, true))
					continue;
				status = PGRES_FATAL_ERROR;
				break;
			case 'A':			/* notify message */
				/* handle notify and go back to processing return values */
				if (getNotify(conn))
					continue;
				break;
			case 'N':			/* notice */
				/* handle notice and go back to processing return values */
				if (pqGetErrorNotice2(conn, false))
					continue;
				break;
			case 'Z':			/* backend is ready for new query */
				/* consume the message and exit */
				conn->inStart = conn->inCursor;
				/* if we saved a result object (probably an error), use it */
				if (conn->result)
					return pqPrepareAsyncResult(conn);
				return PQmakeEmptyPGresult(conn, status);
			default:
				/* The backend violates the protocol. */
				printfPQExpBuffer(&conn->errorMessage,
								  libpq_gettext("protocol error: id=0x%x\n"),
								  id);
				pqSaveErrorResult(conn);
				conn->inStart = conn->inCursor;
				return pqPrepareAsyncResult(conn);
		}
		/* Completed this message, keep going */
		conn->inStart = conn->inCursor;
		needInput = false;
	}

	/*
	 * We fall out of the loop only upon failing to read data.
	 * conn->errorMessage has been set by pqWait or pqReadData. We want to
	 * append it to any already-received error message.
	 */
	pqSaveErrorResult(conn);
	return pqPrepareAsyncResult(conn);
}
Ejemplo n.º 2
0
/*
 *
 *
 * Control Message has msg_type='C'.
 * Control Message is consumed by Receiver thread on mirror side.
 *
 * Data Message has msg_type='M'.
 * Data Message is inserted in Shared memory and consumed by Consumer
 * thread on mirror side.
 */
bool
FileRepConnClient_SendMessage(
							  FileRepConsumerProcIndex_e messageType,
							  bool messageSynchronous,
							  char *message,
							  uint32 messageLength)
{
	char		msgType = 0;
	int			status = STATUS_OK;

#ifdef USE_ASSERT_CHECKING
	int			prevOutCount = filerep_conn->outCount;
#endif							/* // USE_ASSERT_CHECKING */

	switch (messageType)
	{
		case FileRepMessageTypeXLog:
			msgType = '1';
			break;
		case FileRepMessageTypeAO01:
			msgType = '2';
			break;
		case FileRepMessageTypeWriter:
			msgType = '3';
			break;
		case FileRepMessageTypeShutdown:
			msgType = 'S';
			break;
		default:
			return false;
	}

	/**
	 * Note that pqPutMsgStart and pqPutnchar both may grow the connection's internal buffer, and do not
	 *   flush data
	 */
	if (pqPutMsgStart(msgType, true, filerep_conn) < 0)
	{
		return false;
	}

	if (pqPutnchar(message, messageLength, filerep_conn) < 0)
	{
		return false;
	}

	/*
	 * Server side needs complete messages for mode-transitions so disable
	 * auto-flush since it flushes partial messages
	 */
	pqPutMsgEndNoAutoFlush(filerep_conn);

	/* assert that a flush did not occur */
	Assert(prevOutCount + messageLength + 5 == filerep_conn->outCount); /* the +5 is the amount
																		 * added by
																		 * pgPutMsgStart */

	/*
	 * note also that we could do a flush beforehand to avoid having
	 * pqPutMsgStart and pqPutnchar growing the buffer
	 */
	if (messageSynchronous || filerep_conn->outCount >= file_rep_min_data_before_flush)
	{
		int			result = 0;

		/* wait and timeout will be handled by pqWaitTimeout */
		while ((status = pqFlushNonBlocking(filerep_conn)) > 0)
		{
			/* retry on timeout */
			while (!(result = pqWaitTimeout(FALSE, TRUE, filerep_conn, time(NULL) + file_rep_socket_timeout)))
			{
				if (FileRepSubProcess_IsStateTransitionRequested())
				{
					elog(WARNING, "segment state transition requested while waiting to write data to socket");
					status = -1;
					break;
				}
			}

			if (result < 0)
			{
				ereport(WARNING,
						(errcode_for_socket_access(),
						 errmsg("could not write data to socket, failure detected : %m")));
				status = -1;
				break;
			}

			if (status == -1)
			{
				break;
			}
		}

		if (status < 0)
		{
			return false;
		}
		Assert(status == 0);
		return true;
	}

	return true;
}
/*
 * PQfn - Send a function call to the POSTGRES backend.
 *
 * See fe-exec.c for documentation.
 */
PGresult *
pqFunctionCall3(PGconn *conn, Oid fnid,
				int *result_buf, int *actual_result_len,
				int result_is_int,
				const PQArgBlock *args, int nargs)
{
	bool		needInput = false;
	ExecStatusType status = PGRES_FATAL_ERROR;
	char		id;
	int			msgLength;
	int			avail;
	int			i;

	/* PQfn already validated connection state */

	if (pqPutMsgStart('F', false, conn) < 0 ||	/* function call msg */
		pqPutInt(fnid, 4, conn) < 0 ||	/* function id */
		pqPutInt(1, 2, conn) < 0 ||		/* # of format codes */
		pqPutInt(1, 2, conn) < 0 ||		/* format code: BINARY */
		pqPutInt(nargs, 2, conn) < 0)	/* # of args */
	{
		pqHandleSendFailure(conn);
		return NULL;
	}

	for (i = 0; i < nargs; ++i)
	{							/* len.int4 + contents	   */
		if (pqPutInt(args[i].len, 4, conn))
		{
			pqHandleSendFailure(conn);
			return NULL;
		}
		if (args[i].len == -1)
			continue;			/* it's NULL */

		if (args[i].isint)
		{
			if (pqPutInt(args[i].u.integer, args[i].len, conn))
			{
				pqHandleSendFailure(conn);
				return NULL;
			}
		}
		else
		{
			if (pqPutnchar((char *) args[i].u.ptr, args[i].len, conn))
			{
				pqHandleSendFailure(conn);
				return NULL;
			}
		}
	}

	if (pqPutInt(1, 2, conn) < 0)		/* result format code: BINARY */
	{
		pqHandleSendFailure(conn);
		return NULL;
	}

	if (pqPutMsgEnd(conn) < 0 ||
		pqFlush(conn))
	{
		pqHandleSendFailure(conn);
		return NULL;
	}

	for (;;)
	{
		if (needInput)
		{
			/* Wait for some data to arrive (or for the channel to close) */
			if (pqWait(TRUE, FALSE, conn) ||
				pqReadData(conn) < 0)
				break;
		}

		/*
		 * Scan the message. If we run out of data, loop around to try again.
		 */
		needInput = true;

		conn->inCursor = conn->inStart;
		if (pqGetc(&id, conn))
			continue;
		if (pqGetInt(&msgLength, 4, conn))
			continue;

		/*
		 * Try to validate message type/length here.  A length less than 4 is
		 * definitely broken.  Large lengths should only be believed for a few
		 * message types.
		 */
		if (msgLength < 4)
		{
			handleSyncLoss(conn, id, msgLength);
			break;
		}
		if (msgLength > 30000 && !VALID_LONG_MESSAGE_TYPE(id))
		{
			handleSyncLoss(conn, id, msgLength);
			break;
		}

		/*
		 * Can't process if message body isn't all here yet.
		 */
		msgLength -= 4;
		avail = conn->inEnd - conn->inCursor;
		if (avail < msgLength)
		{
			/*
			 * Before looping, enlarge the input buffer if needed to hold the
			 * whole message.  See notes in parseInput.
			 */
			if (pqCheckInBufferSpace(conn->inCursor + msgLength, conn))
			{
				/*
				 * XXX add some better recovery code... plan is to skip over
				 * the message using its length, then report an error. For the
				 * moment, just treat this like loss of sync (which indeed it
				 * might be!)
				 */
				handleSyncLoss(conn, id, msgLength);
				break;
			}
			continue;
		}

		/*
		 * We should see V or E response to the command, but might get N
		 * and/or A notices first. We also need to swallow the final Z before
		 * returning.
		 */
		switch (id)
		{
			case 'V':			/* function result */
				if (pqGetInt(actual_result_len, 4, conn))
					continue;
				if (*actual_result_len != -1)
				{
					if (result_is_int)
					{
						if (pqGetInt(result_buf, *actual_result_len, conn))
							continue;
					}
					else
					{
						if (pqGetnchar((char *) result_buf,
									   *actual_result_len,
									   conn))
							continue;
					}
				}
				/* correctly finished function result message */
				status = PGRES_COMMAND_OK;
				break;
			case 'E':			/* error return */
				if (pqGetErrorNotice3(conn, true))
					continue;
				status = PGRES_FATAL_ERROR;
				break;
			case 'A':			/* notify message */
				/* handle notify and go back to processing return values */
				if (getNotify(conn))
					continue;
				break;
			case 'N':			/* notice */
				/* handle notice and go back to processing return values */
				if (pqGetErrorNotice3(conn, false))
					continue;
				break;
			case 'Z':			/* backend is ready for new query */
				if (getReadyForQuery(conn))
					continue;
				/* consume the message and exit */
				conn->inStart += 5 + msgLength;
				/* if we saved a result object (probably an error), use it */
				if (conn->result)
					return pqPrepareAsyncResult(conn);
				return PQmakeEmptyPGresult(conn, status);
			case 'S':			/* parameter status */
				if (getParameterStatus(conn))
					continue;
				break;
			default:
				/* The backend violates the protocol. */
				printfPQExpBuffer(&conn->errorMessage,
								  libpq_gettext("protocol error: id=0x%x\n"),
								  id);
				pqSaveErrorResult(conn);
				/* trust the specified message length as what to skip */
				conn->inStart += 5 + msgLength;
				return pqPrepareAsyncResult(conn);
		}
		/* Completed this message, keep going */
		/* trust the specified message length as what to skip */
		conn->inStart += 5 + msgLength;
		needInput = false;
	}

	/*
	 * We fall out of the loop only upon failing to read data.
	 * conn->errorMessage has been set by pqWait or pqReadData. We want to
	 * append it to any already-received error message.
	 */
	pqSaveErrorResult(conn);
	return pqPrepareAsyncResult(conn);
}
Ejemplo n.º 4
0
/*
 * Initialize SASL authentication exchange.
 */
static int
pg_SASL_init(PGconn *conn, int payloadlen)
{
	char	   *initialresponse = NULL;
	int			initialresponselen;
	bool		done;
	bool		success;
	const char *selected_mechanism;
	PQExpBufferData mechanism_buf;

	initPQExpBuffer(&mechanism_buf);

	if (conn->sasl_state)
	{
		printfPQExpBuffer(&conn->errorMessage,
						  libpq_gettext("duplicate SASL authentication request\n"));
		goto error;
	}

	/*
	 * Parse the list of SASL authentication mechanisms in the
	 * AuthenticationSASL message, and select the best mechanism that we
	 * support.  (Only SCRAM-SHA-256 is supported at the moment.)
	 */
	selected_mechanism = NULL;
	for (;;)
	{
		if (pqGets(&mechanism_buf, conn))
		{
			printfPQExpBuffer(&conn->errorMessage,
							  "fe_sendauth: invalid authentication request from server: invalid list of authentication mechanisms\n");
			goto error;
		}
		if (PQExpBufferDataBroken(mechanism_buf))
			goto oom_error;

		/* An empty string indicates end of list */
		if (mechanism_buf.data[0] == '\0')
			break;

		/*
		 * If we have already selected a mechanism, just skip through the rest
		 * of the list.
		 */
		if (selected_mechanism)
			continue;

		/*
		 * Do we support this mechanism?
		 */
		if (strcmp(mechanism_buf.data, SCRAM_SHA_256_NAME) == 0)
		{
			char	   *password;

			conn->password_needed = true;
			password = conn->connhost[conn->whichhost].password;
			if (password == NULL)
				password = conn->pgpass;
			if (password == NULL || password[0] == '\0')
			{
				printfPQExpBuffer(&conn->errorMessage,
								  PQnoPasswordSupplied);
				goto error;
			}

			conn->sasl_state = pg_fe_scram_init(conn->pguser, password);
			if (!conn->sasl_state)
				goto oom_error;
			selected_mechanism = SCRAM_SHA_256_NAME;
		}
	}

	if (!selected_mechanism)
	{
		printfPQExpBuffer(&conn->errorMessage,
						  libpq_gettext("none of the server's SASL authentication mechanisms are supported\n"));
		goto error;
	}

	/* Get the mechanism-specific Initial Client Response, if any */
	pg_fe_scram_exchange(conn->sasl_state,
						 NULL, -1,
						 &initialresponse, &initialresponselen,
						 &done, &success, &conn->errorMessage);

	if (done && !success)
		goto error;

	/*
	 * Build a SASLInitialResponse message, and send it.
	 */
	if (pqPutMsgStart('p', true, conn))
		goto error;
	if (pqPuts(selected_mechanism, conn))
		goto error;
	if (initialresponse)
	{
		if (pqPutInt(initialresponselen, 4, conn))
			goto error;
		if (pqPutnchar(initialresponse, initialresponselen, conn))
			goto error;
	}
	if (pqPutMsgEnd(conn))
		goto error;
	if (pqFlush(conn))
		goto error;

	termPQExpBuffer(&mechanism_buf);
	if (initialresponse)
		free(initialresponse);

	return STATUS_OK;

error:
	termPQExpBuffer(&mechanism_buf);
	if (initialresponse)
		free(initialresponse);
	return STATUS_ERROR;

oom_error:
	termPQExpBuffer(&mechanism_buf);
	if (initialresponse)
		free(initialresponse);
	printfPQExpBuffer(&conn->errorMessage,
					  libpq_gettext("out of memory\n"));
	return STATUS_ERROR;
}