Adding upstream version 2.9.5.upstream/2.9.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 489 insertions, 0 deletions

diff --git a/src/raw_sock.c b/src/raw_sock.c
new file mode 100644
index 0000000..1287dc5
--- /dev/null
+++ b/src/raw_sock.c
@@ -0,0 +1,489 @@
+/*
+ * RAW transport layer over SOCK_STREAM sockets.
+ *
+ * Copyright 2000-2012 Willy Tarreau <w@1wt.eu>
+ *
+ * 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.
+ *
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <netinet/tcp.h>
+
+#include <haproxy/api.h>
+#include <haproxy/buf.h>
+#include <haproxy/connection.h>
+#include <haproxy/errors.h>
+#include <haproxy/fd.h>
+#include <haproxy/global.h>
+#include <haproxy/pipe.h>
+#include <haproxy/proxy.h>
+#include <haproxy/tools.h>
+
+
+#if defined(USE_LINUX_SPLICE)
+
+/* A pipe contains 16 segments max, and it's common to see segments of 1448 bytes
+ * because of timestamps. Use this as a hint for not looping on splice().
+ */
+#define SPLICE_FULL_HINT	16*1448
+
+/* how many data we attempt to splice at once when the buffer is configured for
+ * infinite forwarding */
+#define MAX_SPLICE_AT_ONCE	(1<<30)
+
+/* Returns :
+ *   -1 if splice() is not supported
+ *   >= 0 to report the amount of spliced bytes.
+ *   connection flags are updated (error, read0, wait_room, wait_data).
+ *   The caller must have previously allocated the pipe.
+ */
+int raw_sock_to_pipe(struct connection *conn, void *xprt_ctx, struct pipe *pipe, unsigned int count)
+{
+	int ret;
+	int retval = 0;
+
+
+	if (!conn_ctrl_ready(conn))
+		return 0;
+
+	BUG_ON(conn->flags & CO_FL_FDLESS);
+
+	if (!fd_recv_ready(conn->handle.fd))
+		return 0;
+
+	conn->flags &= ~CO_FL_WAIT_ROOM;
+	errno = 0;
+
+	/* Under Linux, if FD_POLL_HUP is set, we have reached the end.
+	 * Since older splice() implementations were buggy and returned
+	 * EAGAIN on end of read, let's bypass the call to splice() now.
+	 */
+	if (unlikely(!(fdtab[conn->handle.fd].state & FD_POLL_IN))) {
+		/* stop here if we reached the end of data */
+		if ((fdtab[conn->handle.fd].state & (FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
+			goto out_read0;
+
+		/* report error on POLL_ERR before connection establishment */
+		if ((fdtab[conn->handle.fd].state & FD_POLL_ERR) && (conn->flags & CO_FL_WAIT_L4_CONN)) {
+			conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_SOCK_WR_SH;
+			errno = 0; /* let the caller do a getsockopt() if it wants it */
+			goto leave;
+		}
+	}
+
+	while (count) {
+		if (count > MAX_SPLICE_AT_ONCE)
+			count = MAX_SPLICE_AT_ONCE;
+
+		ret = splice(conn->handle.fd, NULL, pipe->prod, NULL, count,
+			     SPLICE_F_MOVE|SPLICE_F_NONBLOCK);
+
+		if (ret <= 0) {
+			if (ret == 0)
+				goto out_read0;
+
+			if (errno == EAGAIN || errno == EWOULDBLOCK) {
+				/* there are two reasons for EAGAIN :
+				 *   - nothing in the socket buffer (standard)
+				 *   - pipe is full
+				 * The difference between these two situations
+				 * is problematic. Since we don't know if the
+				 * pipe is full, we'll stop if the pipe is not
+				 * empty. Anyway, we will almost always fill or
+				 * empty the pipe.
+				 */
+				if (pipe->data) {
+					/* always stop reading until the pipe is flushed */
+					conn->flags |= CO_FL_WAIT_ROOM;
+					break;
+				}
+				/* socket buffer exhausted */
+				fd_cant_recv(conn->handle.fd);
+				break;
+			}
+			else if (errno == ENOSYS || errno == EINVAL || errno == EBADF) {
+				/* splice not supported on this end, disable it.
+				 * We can safely return -1 since there is no
+				 * chance that any data has been piped yet.
+				 */
+				retval = -1;
+				goto leave;
+			}
+			else if (errno == EINTR) {
+				/* try again */
+				continue;
+			}
+			/* here we have another error */
+			conn->flags |= CO_FL_ERROR;
+			break;
+		} /* ret <= 0 */
+
+		retval += ret;
+		pipe->data += ret;
+		count -= ret;
+
+		if (pipe->data >= SPLICE_FULL_HINT || ret >= global.tune.recv_enough) {
+			/* We've read enough of it for this time, let's stop before
+			 * being asked to poll.
+			 */
+			conn->flags |= CO_FL_WAIT_ROOM;
+			break;
+		}
+	} /* while */
+
+	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN) && retval)
+		conn->flags &= ~CO_FL_WAIT_L4_CONN;
+
+ leave:
+	if (retval > 0)
+		increment_send_rate(retval, 1);
+
+	return retval;
+
+ out_read0:
+	conn_sock_read0(conn);
+	conn->flags &= ~CO_FL_WAIT_L4_CONN;
+	goto leave;
+}
+
+/* Send as many bytes as possible from the pipe to the connection's socket.
+ */
+int raw_sock_from_pipe(struct connection *conn, void *xprt_ctx, struct pipe *pipe, unsigned int count)
+{
+	int ret, done;
+
+	if (!conn_ctrl_ready(conn))
+		return 0;
+
+	BUG_ON(conn->flags & CO_FL_FDLESS);
+
+	if (!fd_send_ready(conn->handle.fd))
+		return 0;
+
+	if (conn->flags & CO_FL_SOCK_WR_SH) {
+		/* it's already closed */
+		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH;
+		errno = EPIPE;
+		return 0;
+	}
+
+	if (unlikely(count > pipe->data))
+		count = pipe->data;
+
+	done = 0;
+	while (count) {
+		ret = splice(pipe->cons, NULL, conn->handle.fd, NULL, count,
+			     SPLICE_F_MOVE|SPLICE_F_NONBLOCK);
+
+		if (ret <= 0) {
+			if (ret == 0 || errno == EAGAIN || errno == EWOULDBLOCK) {
+				fd_cant_send(conn->handle.fd);
+				break;
+			}
+			else if (errno == EINTR)
+				continue;
+
+			/* here we have another error */
+			conn->flags |= CO_FL_ERROR;
+			break;
+		}
+
+		done += ret;
+		count -= ret;
+		pipe->data -= ret;
+	}
+	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN) && done) {
+		conn->flags &= ~CO_FL_WAIT_L4_CONN;
+	}
+
+	return done;
+}
+
+#endif /* USE_LINUX_SPLICE */
+
+
+/* Receive up to <count> bytes from connection <conn>'s socket and store them
+ * into buffer <buf>. Only one call to recv() is performed, unless the
+ * buffer wraps, in which case a second call may be performed. The connection's
+ * flags are updated with whatever special event is detected (error, read0,
+ * empty). The caller is responsible for taking care of those events and
+ * avoiding the call if inappropriate. The function does not call the
+ * connection's polling update function, so the caller is responsible for this.
+ * errno is cleared before starting so that the caller knows that if it spots an
+ * error without errno, it's pending and can be retrieved via getsockopt(SO_ERROR).
+ */
+static size_t raw_sock_to_buf(struct connection *conn, void *xprt_ctx, struct buffer *buf, size_t count, int flags)
+{
+	ssize_t ret;
+	size_t try, done = 0;
+
+	if (!conn_ctrl_ready(conn))
+		return 0;
+
+	BUG_ON(conn->flags & CO_FL_FDLESS);
+
+	if (!fd_recv_ready(conn->handle.fd))
+		return 0;
+
+	conn->flags &= ~CO_FL_WAIT_ROOM;
+	errno = 0;
+
+	if (unlikely(!(fdtab[conn->handle.fd].state & FD_POLL_IN))) {
+		/* stop here if we reached the end of data */
+		if ((fdtab[conn->handle.fd].state & (FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
+			goto read0;
+
+		/* report error on POLL_ERR before connection establishment */
+		if ((fdtab[conn->handle.fd].state & FD_POLL_ERR) && (conn->flags & CO_FL_WAIT_L4_CONN)) {
+			conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_SOCK_WR_SH;
+			goto leave;
+		}
+	}
+
+	/* read the largest possible block. For this, we perform only one call
+	 * to recv() unless the buffer wraps and we exactly fill the first hunk,
+	 * in which case we accept to do it once again. A new attempt is made on
+	 * EINTR too.
+	 */
+	while (count > 0) {
+		try = b_contig_space(buf);
+		if (!try)
+			break;
+
+		if (try > count)
+			try = count;
+
+		ret = recv(conn->handle.fd, b_tail(buf), try, 0);
+
+		if (ret > 0) {
+			b_add(buf, ret);
+			done += ret;
+			if (ret < try) {
+				/* socket buffer exhausted */
+				fd_cant_recv(conn->handle.fd);
+
+				/* unfortunately, on level-triggered events, POLL_HUP
+				 * is generally delivered AFTER the system buffer is
+				 * empty, unless the poller supports POLL_RDHUP. If
+				 * we know this is the case, we don't try to read more
+				 * as we know there's no more available. Similarly, if
+				 * there's no problem with lingering we don't even try
+				 * to read an unlikely close from the client since we'll
+				 * close first anyway.
+				 */
+				if (fdtab[conn->handle.fd].state & FD_POLL_HUP)
+					goto read0;
+
+				if (!(fdtab[conn->handle.fd].state & FD_LINGER_RISK) ||
+				    (cur_poller.flags & HAP_POLL_F_RDHUP)) {
+					break;
+				}
+			}
+			count -= ret;
+
+			if (flags & CO_RFL_READ_ONCE)
+				break;
+		}
+		else if (ret == 0) {
+			goto read0;
+		}
+		else if (errno == EAGAIN || errno == EWOULDBLOCK || errno == ENOTCONN) {
+			/* socket buffer exhausted */
+			fd_cant_recv(conn->handle.fd);
+			break;
+		}
+		else if (errno != EINTR) {
+			conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_SOCK_WR_SH;
+			break;
+		}
+	}
+
+	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN) && done)
+		conn->flags &= ~CO_FL_WAIT_L4_CONN;
+
+ leave:
+	return done;
+
+ read0:
+	conn_sock_read0(conn);
+	conn->flags &= ~CO_FL_WAIT_L4_CONN;
+
+	/* Now a final check for a possible asynchronous low-level error
+	 * report. This can happen when a connection receives a reset
+	 * after a shutdown, both POLL_HUP and POLL_ERR are queued, and
+	 * we might have come from there by just checking POLL_HUP instead
+	 * of recv()'s return value 0, so we have no way to tell there was
+	 * an error without checking.
+	 */
+	if (unlikely(!done && fdtab[conn->handle.fd].state & FD_POLL_ERR))
+		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_SOCK_WR_SH;
+	goto leave;
+}
+
+
+/* Send up to <count> pending bytes from buffer <buf> to connection <conn>'s
+ * socket. <flags> may contain some CO_SFL_* flags to hint the system about
+ * other pending data for example, but this flag is ignored at the moment.
+ * Only one call to send() is performed, unless the buffer wraps, in which case
+ * a second call may be performed. The connection's flags are updated with
+ * whatever special event is detected (error, empty). The caller is responsible
+ * for taking care of those events and avoiding the call if inappropriate. The
+ * function does not call the connection's polling update function, so the caller
+ * is responsible for this. It's up to the caller to update the buffer's contents
+ * based on the return value.
+ */
+static size_t raw_sock_from_buf(struct connection *conn, void *xprt_ctx, const struct buffer *buf, size_t count, int flags)
+{
+	ssize_t ret;
+	size_t try, done;
+	int send_flag;
+
+	if (!conn_ctrl_ready(conn))
+		return 0;
+
+	BUG_ON(conn->flags & CO_FL_FDLESS);
+
+	if (!fd_send_ready(conn->handle.fd))
+		return 0;
+
+	if (unlikely(fdtab[conn->handle.fd].state & FD_POLL_ERR)) {
+		/* an error was reported on the FD, we can't send anymore */
+		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_WR_SH | CO_FL_SOCK_RD_SH;
+		errno = EPIPE;
+		return 0;
+	}
+
+	if (conn->flags & CO_FL_SOCK_WR_SH) {
+		/* it's already closed */
+		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH;
+		errno = EPIPE;
+		return 0;
+	}
+
+	done = 0;
+	/* send the largest possible block. For this we perform only one call
+	 * to send() unless the buffer wraps and we exactly fill the first hunk,
+	 * in which case we accept to do it once again.
+	 */
+	while (count) {
+		try = b_contig_data(buf, done);
+		if (try > count)
+			try = count;
+
+		send_flag = MSG_DONTWAIT | MSG_NOSIGNAL;
+		if (try < count || flags & CO_SFL_MSG_MORE)
+			send_flag |= MSG_MORE;
+
+		ret = send(conn->handle.fd, b_peek(buf, done), try, send_flag);
+
+		if (ret > 0) {
+			count -= ret;
+			done += ret;
+
+			/* if the system buffer is full, don't insist */
+			if (ret < try) {
+				fd_cant_send(conn->handle.fd);
+				break;
+			}
+			if (!count)
+				fd_stop_send(conn->handle.fd);
+		}
+		else if (ret == 0 || errno == EAGAIN || errno == EWOULDBLOCK || errno == ENOTCONN || errno == EINPROGRESS) {
+			/* nothing written, we need to poll for write first */
+			fd_cant_send(conn->handle.fd);
+			break;
+		}
+		else if (errno != EINTR) {
+			conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_SOCK_WR_SH;
+			break;
+		}
+	}
+	if (unlikely(conn->flags & CO_FL_WAIT_L4_CONN) && done) {
+		conn->flags &= ~CO_FL_WAIT_L4_CONN;
+	}
+
+	if (done > 0)
+		increment_send_rate(done, 0);
+
+	return done;
+}
+
+/* Called from the upper layer, to subscribe <es> to events <event_type>. The
+ * event subscriber <es> is not allowed to change from a previous call as long
+ * as at least one event is still subscribed. The <event_type> must only be a
+ * combination of SUB_RETRY_RECV and SUB_RETRY_SEND. It always returns 0.
+ */
+static int raw_sock_subscribe(struct connection *conn, void *xprt_ctx, int event_type, struct wait_event *es)
+{
+	return conn_subscribe(conn, xprt_ctx, event_type, es);
+}
+
+/* Called from the upper layer, to unsubscribe <es> from events <event_type>.
+ * The <es> pointer is not allowed to differ from the one passed to the
+ * subscribe() call. It always returns zero.
+ */
+static int raw_sock_unsubscribe(struct connection *conn, void *xprt_ctx, int event_type, struct wait_event *es)
+{
+	return conn_unsubscribe(conn, xprt_ctx, event_type, es);
+}
+
+static void raw_sock_close(struct connection *conn, void *xprt_ctx)
+{
+	if (conn->subs != NULL) {
+		conn_unsubscribe(conn, NULL, conn->subs->events, conn->subs);
+	}
+}
+
+/* We can't have an underlying XPRT, so just return -1 to signify failure */
+static int raw_sock_remove_xprt(struct connection *conn, void *xprt_ctx, void *toremove_ctx, const struct xprt_ops *newops, void *newctx)
+{
+	/* This is the lowest xprt we can have, so if we get there we didn't
+	 * find the xprt we wanted to remove, that's a bug
+	 */
+	BUG_ON(1);
+	return -1;
+}
+
+/* transport-layer operations for RAW sockets */
+static struct xprt_ops raw_sock = {
+	.snd_buf  = raw_sock_from_buf,
+	.rcv_buf  = raw_sock_to_buf,
+	.subscribe = raw_sock_subscribe,
+	.unsubscribe = raw_sock_unsubscribe,
+	.remove_xprt = raw_sock_remove_xprt,
+#if defined(USE_LINUX_SPLICE)
+	.rcv_pipe = raw_sock_to_pipe,
+	.snd_pipe = raw_sock_from_pipe,
+#endif
+	.shutr    = NULL,
+	.shutw    = NULL,
+	.close    = raw_sock_close,
+	.name     = "RAW",
+};
+
+
+static void __raw_sock_init(void)
+{
+	xprt_register(XPRT_RAW, &raw_sock);
+}
+
+INITCALL0(STG_REGISTER, __raw_sock_init);
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */