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/*
* include/proto/connection.h
* This file contains connection function prototypes
*
* Copyright (C) 2000-2012 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _PROTO_CONNECTION_H
#define _PROTO_CONNECTION_H
#include <common/config.h>
#include <common/memory.h>
#include <types/connection.h>
#include <types/listener.h>
#include <proto/fd.h>
#include <proto/obj_type.h>
extern struct pool_head *pool2_connection;
/* perform minimal intializations, report 0 in case of error, 1 if OK. */
int init_connection();
/* I/O callback for fd-based connections. It calls the read/write handlers
* provided by the connection's sock_ops. Returns 0.
*/
int conn_fd_handler(int fd);
/* receive a PROXY protocol header over a connection */
int conn_recv_proxy(struct connection *conn, int flag);
int make_proxy_line(char *buf, int buf_len, struct server *srv, struct connection *remote);
int make_proxy_line_v1(char *buf, int buf_len, struct sockaddr_storage *src, struct sockaddr_storage *dst);
int make_proxy_line_v2(char *buf, int buf_len, struct server *srv, struct connection *remote);
/* returns true is the transport layer is ready */
static inline int conn_xprt_ready(const struct connection *conn)
{
return (conn->flags & CO_FL_XPRT_READY);
}
/* returns true is the control layer is ready */
static inline int conn_ctrl_ready(const struct connection *conn)
{
return (conn->flags & CO_FL_CTRL_READY);
}
/* Calls the init() function of the transport layer if any and if not done yet,
* and sets the CO_FL_XPRT_READY flag to indicate it was properly initialized.
* Returns <0 in case of error.
*/
static inline int conn_xprt_init(struct connection *conn)
{
int ret = 0;
if (!conn_xprt_ready(conn) && conn->xprt && conn->xprt->init)
ret = conn->xprt->init(conn);
if (ret >= 0)
conn->flags |= CO_FL_XPRT_READY;
return ret;
}
/* Calls the close() function of the transport layer if any and if not done
* yet, and clears the CO_FL_XPRT_READY flag. However this is not done if the
* CO_FL_XPRT_TRACKED flag is set, which allows logs to take data from the
* transport layer very late if needed.
*/
static inline void conn_xprt_close(struct connection *conn)
{
if ((conn->flags & (CO_FL_XPRT_READY|CO_FL_XPRT_TRACKED)) == CO_FL_XPRT_READY) {
if (conn->xprt->close)
conn->xprt->close(conn);
conn->flags &= ~CO_FL_XPRT_READY;
}
}
/* Initializes the connection's control layer which essentially consists in
* registering the file descriptor for polling and setting the CO_FL_CTRL_READY
* flag. The caller is responsible for ensuring that the control layer is
* already assigned to the connection prior to the call.
*/
static inline void conn_ctrl_init(struct connection *conn)
{
if (!conn_ctrl_ready(conn)) {
int fd = conn->t.sock.fd;
fd_insert(fd);
/* mark the fd as ready so as not to needlessly poll at the beginning */
fd_may_recv(fd);
fd_may_send(fd);
fdtab[fd].owner = conn;
fdtab[fd].iocb = conn_fd_handler;
conn->flags |= CO_FL_CTRL_READY;
}
}
/* Deletes the FD if the transport layer is already gone. Once done,
* it then removes the CO_FL_CTRL_READY flag.
*/
static inline void conn_ctrl_close(struct connection *conn)
{
if ((conn->flags & (CO_FL_XPRT_READY|CO_FL_CTRL_READY)) == CO_FL_CTRL_READY) {
fd_delete(conn->t.sock.fd);
conn->flags &= ~CO_FL_CTRL_READY;
}
}
/* If the connection still has a transport layer, then call its close() function
* if any, and delete the file descriptor if a control layer is set. This is
* used to close everything at once and atomically. However this is not done if
* the CO_FL_XPRT_TRACKED flag is set, which allows logs to take data from the
* transport layer very late if needed.
*/
static inline void conn_full_close(struct connection *conn)
{
conn_xprt_close(conn);
conn_ctrl_close(conn);
}
/* Force to close the connection whatever the tracking state. This is mainly
* used on the error path where the tracking does not make sense, or to kill
* an idle connection we want to abort immediately.
*/
static inline void conn_force_close(struct connection *conn)
{
if (conn_xprt_ready(conn) && conn->xprt->close)
conn->xprt->close(conn);
if (conn_ctrl_ready(conn))
fd_delete(conn->t.sock.fd);
conn->flags &= ~(CO_FL_XPRT_READY|CO_FL_CTRL_READY);
}
/* Update polling on connection <c>'s file descriptor depending on its current
* state as reported in the connection's CO_FL_CURR_* flags, reports of EAGAIN
* in CO_FL_WAIT_*, and the sock layer expectations indicated by CO_FL_SOCK_*.
* The connection flags are updated with the new flags at the end of the
* operation. Polling is totally disabled if an error was reported.
*/
void conn_update_sock_polling(struct connection *c);
/* Update polling on connection <c>'s file descriptor depending on its current
* state as reported in the connection's CO_FL_CURR_* flags, reports of EAGAIN
* in CO_FL_WAIT_*, and the data layer expectations indicated by CO_FL_DATA_*.
* The connection flags are updated with the new flags at the end of the
* operation. Polling is totally disabled if an error was reported.
*/
void conn_update_data_polling(struct connection *c);
/* Refresh the connection's polling flags from its file descriptor status.
* This should be called at the beginning of a connection handler.
*/
static inline void conn_refresh_polling_flags(struct connection *conn)
{
conn->flags &= ~(CO_FL_WAIT_ROOM | CO_FL_WAIT_DATA);
if (conn_ctrl_ready(conn)) {
unsigned int flags = conn->flags & ~(CO_FL_CURR_RD_ENA | CO_FL_CURR_WR_ENA);
if (fd_recv_active(conn->t.sock.fd))
flags |= CO_FL_CURR_RD_ENA;
if (fd_send_active(conn->t.sock.fd))
flags |= CO_FL_CURR_WR_ENA;
conn->flags = flags;
}
}
/* inspects c->flags and returns non-zero if DATA ENA changes from the CURR ENA
* or if the WAIT flags are set with their respective ENA flags. Additionally,
* non-zero is also returned if an error was reported on the connection. This
* function is used quite often and is inlined. In order to proceed optimally
* with very little code and CPU cycles, the bits are arranged so that a change
* can be detected by a few left shifts, a xor, and a mask. These operations
* detect when W&D are both enabled for either direction, when C&D differ for
* either direction and when Error is set. The trick consists in first keeping
* only the bits we're interested in, since they don't collide when shifted,
* and to perform the AND at the end. In practice, the compiler is able to
* replace the last AND with a TEST in boolean conditions. This results in
* checks that are done in 4-6 cycles and less than 30 bytes.
*/
static inline unsigned int conn_data_polling_changes(const struct connection *c)
{
unsigned int f = c->flags;
f &= CO_FL_DATA_WR_ENA | CO_FL_DATA_RD_ENA | CO_FL_CURR_WR_ENA |
CO_FL_CURR_RD_ENA | CO_FL_ERROR;
f = (f ^ (f << 1)) & (CO_FL_CURR_WR_ENA|CO_FL_CURR_RD_ENA); /* test C ^ D */
return f & (CO_FL_CURR_WR_ENA | CO_FL_CURR_RD_ENA | CO_FL_ERROR);
}
/* inspects c->flags and returns non-zero if SOCK ENA changes from the CURR ENA
* or if the WAIT flags are set with their respective ENA flags. Additionally,
* non-zero is also returned if an error was reported on the connection. This
* function is used quite often and is inlined. In order to proceed optimally
* with very little code and CPU cycles, the bits are arranged so that a change
* can be detected by a few left shifts, a xor, and a mask. These operations
* detect when W&S are both enabled for either direction, when C&S differ for
* either direction and when Error is set. The trick consists in first keeping
* only the bits we're interested in, since they don't collide when shifted,
* and to perform the AND at the end. In practice, the compiler is able to
* replace the last AND with a TEST in boolean conditions. This results in
* checks that are done in 4-6 cycles and less than 30 bytes.
*/
static inline unsigned int conn_sock_polling_changes(const struct connection *c)
{
unsigned int f = c->flags;
f &= CO_FL_SOCK_WR_ENA | CO_FL_SOCK_RD_ENA | CO_FL_CURR_WR_ENA |
CO_FL_CURR_RD_ENA | CO_FL_ERROR;
f = (f ^ (f << 2)) & (CO_FL_CURR_WR_ENA|CO_FL_CURR_RD_ENA); /* test C ^ S */
return f & (CO_FL_CURR_WR_ENA | CO_FL_CURR_RD_ENA | CO_FL_ERROR);
}
/* Automatically updates polling on connection <c> depending on the DATA flags
* if no handshake is in progress.
*/
static inline void conn_cond_update_data_polling(struct connection *c)
{
if (!(c->flags & CO_FL_POLL_SOCK) && conn_data_polling_changes(c))
conn_update_data_polling(c);
}
/* Automatically updates polling on connection <c> depending on the SOCK flags
* if a handshake is in progress.
*/
static inline void conn_cond_update_sock_polling(struct connection *c)
{
if ((c->flags & CO_FL_POLL_SOCK) && conn_sock_polling_changes(c))
conn_update_sock_polling(c);
}
/* Stop all polling on the fd. This might be used when an error is encountered
* for example.
*/
static inline void conn_stop_polling(struct connection *c)
{
c->flags &= ~(CO_FL_CURR_RD_ENA | CO_FL_CURR_WR_ENA |
CO_FL_SOCK_RD_ENA | CO_FL_SOCK_WR_ENA |
CO_FL_DATA_RD_ENA | CO_FL_DATA_WR_ENA);
fd_stop_both(c->t.sock.fd);
}
/* Automatically update polling on connection <c> depending on the DATA and
* SOCK flags, and on whether a handshake is in progress or not. This may be
* called at any moment when there is a doubt about the effectiveness of the
* polling state, for instance when entering or leaving the handshake state.
*/
static inline void conn_cond_update_polling(struct connection *c)
{
if (unlikely(c->flags & CO_FL_ERROR))
conn_stop_polling(c);
else if (!(c->flags & CO_FL_POLL_SOCK) && conn_data_polling_changes(c))
conn_update_data_polling(c);
else if ((c->flags & CO_FL_POLL_SOCK) && conn_sock_polling_changes(c))
conn_update_sock_polling(c);
}
/***** Event manipulation primitives for use by DATA I/O callbacks *****/
/* The __conn_* versions do not propagate to lower layers and are only meant
* to be used by handlers called by the connection handler. The other ones
* may be used anywhere.
*/
static inline void __conn_data_want_recv(struct connection *c)
{
c->flags |= CO_FL_DATA_RD_ENA;
}
static inline void __conn_data_stop_recv(struct connection *c)
{
c->flags &= ~CO_FL_DATA_RD_ENA;
}
static inline void __conn_data_want_send(struct connection *c)
{
c->flags |= CO_FL_DATA_WR_ENA;
}
static inline void __conn_data_stop_send(struct connection *c)
{
c->flags &= ~CO_FL_DATA_WR_ENA;
}
static inline void __conn_data_stop_both(struct connection *c)
{
c->flags &= ~(CO_FL_DATA_WR_ENA | CO_FL_DATA_RD_ENA);
}
static inline void conn_data_want_recv(struct connection *c)
{
__conn_data_want_recv(c);
conn_cond_update_data_polling(c);
}
static inline void conn_data_stop_recv(struct connection *c)
{
__conn_data_stop_recv(c);
conn_cond_update_data_polling(c);
}
static inline void conn_data_want_send(struct connection *c)
{
__conn_data_want_send(c);
conn_cond_update_data_polling(c);
}
static inline void conn_data_stop_send(struct connection *c)
{
__conn_data_stop_send(c);
conn_cond_update_data_polling(c);
}
static inline void conn_data_stop_both(struct connection *c)
{
__conn_data_stop_both(c);
conn_cond_update_data_polling(c);
}
/***** Event manipulation primitives for use by handshake I/O callbacks *****/
/* The __conn_* versions do not propagate to lower layers and are only meant
* to be used by handlers called by the connection handler. The other ones
* may be used anywhere.
*/
static inline void __conn_sock_want_recv(struct connection *c)
{
c->flags |= CO_FL_SOCK_RD_ENA;
}
static inline void __conn_sock_stop_recv(struct connection *c)
{
c->flags &= ~CO_FL_SOCK_RD_ENA;
}
static inline void __conn_sock_want_send(struct connection *c)
{
c->flags |= CO_FL_SOCK_WR_ENA;
}
static inline void __conn_sock_stop_send(struct connection *c)
{
c->flags &= ~CO_FL_SOCK_WR_ENA;
}
static inline void __conn_sock_stop_both(struct connection *c)
{
c->flags &= ~(CO_FL_SOCK_WR_ENA | CO_FL_SOCK_RD_ENA);
}
static inline void conn_sock_want_recv(struct connection *c)
{
__conn_sock_want_recv(c);
conn_cond_update_sock_polling(c);
}
static inline void conn_sock_stop_recv(struct connection *c)
{
__conn_sock_stop_recv(c);
conn_cond_update_sock_polling(c);
}
static inline void conn_sock_want_send(struct connection *c)
{
__conn_sock_want_send(c);
conn_cond_update_sock_polling(c);
}
static inline void conn_sock_stop_send(struct connection *c)
{
__conn_sock_stop_send(c);
conn_cond_update_sock_polling(c);
}
static inline void conn_sock_stop_both(struct connection *c)
{
__conn_sock_stop_both(c);
conn_cond_update_sock_polling(c);
}
/* shutdown management */
static inline void conn_sock_read0(struct connection *c)
{
c->flags |= CO_FL_SOCK_RD_SH;
__conn_sock_stop_recv(c);
/* we don't risk keeping ports unusable if we found the
* zero from the other side.
*/
if (conn_ctrl_ready(c))
fdtab[c->t.sock.fd].linger_risk = 0;
}
static inline void conn_data_read0(struct connection *c)
{
c->flags |= CO_FL_DATA_RD_SH;
__conn_data_stop_recv(c);
}
static inline void conn_sock_shutw(struct connection *c)
{
c->flags |= CO_FL_SOCK_WR_SH;
__conn_sock_stop_send(c);
}
static inline void conn_data_shutw(struct connection *c)
{
c->flags |= CO_FL_DATA_WR_SH;
__conn_data_stop_send(c);
}
/* detect sock->data read0 transition */
static inline int conn_data_read0_pending(struct connection *c)
{
return (c->flags & (CO_FL_DATA_RD_SH | CO_FL_SOCK_RD_SH)) == CO_FL_SOCK_RD_SH;
}
/* detect data->sock shutw transition */
static inline int conn_sock_shutw_pending(struct connection *c)
{
return (c->flags & (CO_FL_DATA_WR_SH | CO_FL_SOCK_WR_SH)) == CO_FL_DATA_WR_SH;
}
/* prepares a connection to work with protocol <proto> and transport <xprt>.
* The transport's context is initialized as well.
*/
static inline void conn_prepare(struct connection *conn, const struct protocol *proto, const struct xprt_ops *xprt)
{
conn->ctrl = proto;
conn->xprt = xprt;
conn->xprt_st = 0;
conn->xprt_ctx = NULL;
}
/* Initializes all required fields for a new connection. Note that it does the
* minimum acceptable initialization for a connection that already exists and
* is about to be reused. It also leaves the addresses untouched, which makes
* it usable across connection retries to reset a connection to a known state.
*/
static inline void conn_init(struct connection *conn)
{
conn->obj_type = OBJ_TYPE_CONN;
conn->flags = CO_FL_NONE;
conn->data = NULL;
conn->owner = NULL;
conn->send_proxy_ofs = 0;
conn->t.sock.fd = -1; /* just to help with debugging */
conn->err_code = CO_ER_NONE;
conn->target = NULL;
}
/* Tries to allocate a new connection and initialized its main fields. The
* connection is returned on success, NULL on failure. The connection must
* be released using pool_free2() or conn_free().
*/
static inline struct connection *conn_new()
{
struct connection *conn;
conn = pool_alloc2(pool2_connection);
if (likely(conn != NULL))
conn_init(conn);
return conn;
}
/* Releases a connection previously allocated by conn_new() */
static inline void conn_free(struct connection *conn)
{
pool_free2(pool2_connection, conn);
}
/* Retrieves the connection's source address */
static inline void conn_get_from_addr(struct connection *conn)
{
if (conn->flags & CO_FL_ADDR_FROM_SET)
return;
if (!conn_ctrl_ready(conn) || !conn->ctrl->get_src)
return;
if (conn->ctrl->get_src(conn->t.sock.fd, (struct sockaddr *)&conn->addr.from,
sizeof(conn->addr.from),
obj_type(conn->target) != OBJ_TYPE_LISTENER) == -1)
return;
conn->flags |= CO_FL_ADDR_FROM_SET;
}
/* Retrieves the connection's original destination address */
static inline void conn_get_to_addr(struct connection *conn)
{
if (conn->flags & CO_FL_ADDR_TO_SET)
return;
if (!conn_ctrl_ready(conn) || !conn->ctrl->get_dst)
return;
if (conn->ctrl->get_dst(conn->t.sock.fd, (struct sockaddr *)&conn->addr.to,
sizeof(conn->addr.to),
obj_type(conn->target) != OBJ_TYPE_LISTENER) == -1)
return;
conn->flags |= CO_FL_ADDR_TO_SET;
}
/* Attaches a connection to an owner and assigns a data layer */
static inline void conn_attach(struct connection *conn, void *owner, const struct data_cb *data)
{
conn->data = data;
conn->owner = owner;
}
/* Drains possibly pending incoming data on the file descriptor attached to the
* connection and update the connection's flags accordingly. This is used to
* know whether we need to disable lingering on close. Returns non-zero if it
* is safe to close without disabling lingering, otherwise zero. The SOCK_RD_SH
* flag may also be updated if the incoming shutdown was reported by the drain()
* function.
*/
static inline int conn_drain(struct connection *conn)
{
if (!conn_ctrl_ready(conn))
return 1;
if (conn->flags & CO_FL_SOCK_RD_SH)
return 1;
if (!fd_recv_ready(conn->t.sock.fd))
return 0;
if (!conn->ctrl->drain)
return 0;
if (conn->ctrl->drain(conn->t.sock.fd) <= 0)
return 0;
conn->flags |= CO_FL_SOCK_RD_SH;
return 1;
}
/* returns a human-readable error code for conn->err_code, or NULL if the code
* is unknown.
*/
static inline const char *conn_err_code_str(struct connection *c)
{
switch (c->err_code) {
case CO_ER_NONE: return "Success";
case CO_ER_CONF_FDLIM: return "Reached configured maxconn value";
case CO_ER_PROC_FDLIM: return "Too many sockets on the process";
case CO_ER_SYS_FDLIM: return "Too many sockets on the system";
case CO_ER_SYS_MEMLIM: return "Out of system buffers";
case CO_ER_NOPROTO: return "Protocol or address family not supported";
case CO_ER_SOCK_ERR: return "General socket error";
case CO_ER_PORT_RANGE: return "Source port range exhausted";
case CO_ER_CANT_BIND: return "Can't bind to source address";
case CO_ER_FREE_PORTS: return "Out of local source ports on the system";
case CO_ER_ADDR_INUSE: return "Local source address already in use";
case CO_ER_PRX_EMPTY: return "Connection closed while waiting for PROXY protocol header";
case CO_ER_PRX_ABORT: return "Connection error while waiting for PROXY protocol header";
case CO_ER_PRX_TIMEOUT: return "Timeout while waiting for PROXY protocol header";
case CO_ER_PRX_TRUNCATED: return "Truncated PROXY protocol header received";
case CO_ER_PRX_NOT_HDR: return "Received something which does not look like a PROXY protocol header";
case CO_ER_PRX_BAD_HDR: return "Received an invalid PROXY protocol header";
case CO_ER_PRX_BAD_PROTO: return "Received an unhandled protocol in the PROXY protocol header";
case CO_ER_SSL_EMPTY: return "Connection closed during SSL handshake";
case CO_ER_SSL_ABORT: return "Connection error during SSL handshake";
case CO_ER_SSL_TIMEOUT: return "Timeout during SSL handshake";
case CO_ER_SSL_TOO_MANY: return "Too many SSL connections";
case CO_ER_SSL_NO_MEM: return "Out of memory when initializing an SSL connection";
case CO_ER_SSL_RENEG: return "Rejected a client-initiated SSL renegociation attempt";
case CO_ER_SSL_CA_FAIL: return "SSL client CA chain cannot be verified";
case CO_ER_SSL_CRT_FAIL: return "SSL client certificate not trusted";
case CO_ER_SSL_HANDSHAKE: return "SSL handshake failure";
case CO_ER_SSL_HANDSHAKE_HB: return "SSL handshake failure after heartbeat";
case CO_ER_SSL_KILLED_HB: return "Stopped a TLSv1 heartbeat attack (CVE-2014-0160)";
case CO_ER_SSL_NO_TARGET: return "Attempt to use SSL on an unknown target (internal error)";
}
return NULL;
}
#endif /* _PROTO_CONNECTION_H */
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/