MEDIUM: connection: add a new local send-proxy transport callback
This callback sends a PROXY protocol line on the outgoing connection,
with the local and remote endpoint information. This is used for local
connections (eg: health checks) where the other end needs to have a
valid address and no connection is relayed.
diff --git a/include/proto/connection.h b/include/proto/connection.h
index 949cf11..37af379 100644
--- a/include/proto/connection.h
+++ b/include/proto/connection.h
@@ -68,6 +68,20 @@
*/
void conn_update_data_polling(struct connection *c);
+/* This callback is used to send a valid PROXY protocol line to a socket being
+ * established from the local machine. It sets the protocol addresses to the
+ * local and remote address. This is typically used with health checks or when
+ * it is not possible to determine the other end's address. It returns 0 if it
+ * fails in a fatal way or needs to poll to go further, otherwise it returns
+ * non-zero and removes itself from the connection's flags (the bit is provided
+ * in <flag> by the caller). It is designed to be called by the connection
+ * handler and relies on it to commit polling changes. Note that this function
+ * expects to be able to send the whole line at once, which should always be
+ * possible since it is supposed to start at the first byte of the outgoing
+ * data segment.
+ */
+int conn_local_send_proxy(struct connection *conn, unsigned int flag);
+
/* inspects c->flags and returns non-zero if DATA ENA changes from the CURR ENA
* or if the WAIT flags set new flags that were not in CURR POL. Additionally,
* non-zero is also returned if an error was reported on the connection. This
diff --git a/include/types/connection.h b/include/types/connection.h
index 3219309..35ce1f5 100644
--- a/include/types/connection.h
+++ b/include/types/connection.h
@@ -133,10 +133,11 @@
*/
CO_FL_SI_SEND_PROXY = 0x01000000, /* send a valid PROXY protocol header */
CO_FL_SSL_WAIT_HS = 0x02000000, /* wait for an SSL handshake to complete */
- CO_FL_ACCEPT_PROXY = 0x04000000, /* send a valid PROXY protocol header */
+ CO_FL_ACCEPT_PROXY = 0x04000000, /* receive a valid PROXY protocol header */
+ CO_FL_LOCAL_SPROXY = 0x08000000, /* send a valid local PROXY protocol header */
/* below we have all handshake flags grouped into one */
- CO_FL_HANDSHAKE = CO_FL_SI_SEND_PROXY | CO_FL_SSL_WAIT_HS | CO_FL_ACCEPT_PROXY,
+ CO_FL_HANDSHAKE = CO_FL_SI_SEND_PROXY | CO_FL_SSL_WAIT_HS | CO_FL_ACCEPT_PROXY | CO_FL_LOCAL_SPROXY,
/* when any of these flags is set, polling is defined by socket-layer
* operations, as opposed to data-layer. Transport is explicitly not
diff --git a/src/connection.c b/src/connection.c
index 9b2e92a..b728225 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -17,6 +17,7 @@
#include <proto/connection.h>
#include <proto/fd.h>
+#include <proto/frontend.h>
#include <proto/proto_tcp.h>
#include <proto/session.h>
#include <proto/stream_interface.h>
@@ -59,6 +60,10 @@
if (conn->flags & CO_FL_SI_SEND_PROXY)
if (!conn_si_send_proxy(conn, CO_FL_SI_SEND_PROXY))
goto leave;
+
+ if (conn->flags & CO_FL_LOCAL_SPROXY)
+ if (!conn_local_send_proxy(conn, CO_FL_LOCAL_SPROXY))
+ goto leave;
#ifdef USE_OPENSSL
if (conn->flags & CO_FL_SSL_WAIT_HS)
if (!ssl_sock_handshake(conn, CO_FL_SSL_WAIT_HS))
@@ -508,3 +513,73 @@
}
return ret;
}
+
+/* This callback is used to send a valid PROXY protocol line to a socket being
+ * established from the local machine. It sets the protocol addresses to the
+ * local and remote address. This is typically used with health checks or when
+ * it is not possible to determine the other end's address. It returns 0 if it
+ * fails in a fatal way or needs to poll to go further, otherwise it returns
+ * non-zero and removes itself from the connection's flags (the bit is provided
+ * in <flag> by the caller). It is designed to be called by the connection
+ * handler and relies on it to commit polling changes. Note that this function
+ * expects to be able to send the whole line at once, which should always be
+ * possible since it is supposed to start at the first byte of the outgoing
+ * data segment.
+ */
+int conn_local_send_proxy(struct connection *conn, unsigned int flag)
+{
+ int ret, len;
+
+ /* we might have been called just after an asynchronous shutw */
+ if (conn->flags & CO_FL_SOCK_WR_SH)
+ goto out_error;
+
+ /* The target server expects a PROXY line to be sent first. */
+ conn_get_from_addr(conn);
+ if (!(conn->flags & CO_FL_ADDR_FROM_SET))
+ goto out_error;
+
+ conn_get_to_addr(conn);
+ if (!(conn->flags & CO_FL_ADDR_TO_SET))
+ goto out_error;
+
+ len = make_proxy_line(trash, trashlen, &conn->addr.from, &conn->addr.to);
+ if (!len)
+ goto out_error;
+
+ /* we have to send trash from len bytes. If the data layer has a
+ * pending write, we'll also set MSG_MORE.
+ */
+ ret = send(conn->t.sock.fd, trash, len, (conn->flags & CO_FL_DATA_WR_ENA) ? MSG_MORE : 0);
+
+ if (ret == 0)
+ goto out_wait;
+
+ if (ret < 0) {
+ if (errno == EAGAIN)
+ goto out_wait;
+ goto out_error;
+ }
+
+ if (ret != len)
+ goto out_error;
+
+ /* The connection is ready now, simply return and let the connection
+ * handler notify upper layers if needed.
+ */
+ if (conn->flags & CO_FL_WAIT_L4_CONN)
+ conn->flags &= ~CO_FL_WAIT_L4_CONN;
+ conn->flags &= ~flag;
+ return 1;
+
+ out_error:
+ /* Write error on the file descriptor */
+ conn->flags |= CO_FL_ERROR;
+ conn->flags &= ~flag;
+ return 0;
+
+ out_wait:
+ __conn_sock_stop_recv(conn);
+ __conn_sock_poll_send(conn);
+ return 0;
+}