Adding upstream version 1:8.4p1.upstream/1%8.4p1upstream

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

1 files changed, 355 insertions, 0 deletions

diff --git a/channels.h b/channels.h
new file mode 100644
index 0000000..74e9b3f
--- /dev/null
+++ b/channels.h
@@ -0,0 +1,355 @@
+/* $OpenBSD: channels.h,v 1.135 2020/09/20 05:47:25 djm Exp $ */
+
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+/*
+ * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef CHANNEL_H
+#define CHANNEL_H
+
+/* Definitions for channel types. */
+#define SSH_CHANNEL_X11_LISTENER	1	/* Listening for inet X11 conn. */
+#define SSH_CHANNEL_PORT_LISTENER	2	/* Listening on a port. */
+#define SSH_CHANNEL_OPENING		3	/* waiting for confirmation */
+#define SSH_CHANNEL_OPEN		4	/* normal open two-way channel */
+#define SSH_CHANNEL_CLOSED		5	/* waiting for close confirmation */
+#define SSH_CHANNEL_AUTH_SOCKET		6	/* authentication socket */
+#define SSH_CHANNEL_X11_OPEN		7	/* reading first X11 packet */
+#define SSH_CHANNEL_LARVAL		10	/* larval session */
+#define SSH_CHANNEL_RPORT_LISTENER	11	/* Listening to a R-style port  */
+#define SSH_CHANNEL_CONNECTING		12
+#define SSH_CHANNEL_DYNAMIC		13
+#define SSH_CHANNEL_ZOMBIE		14	/* Almost dead. */
+#define SSH_CHANNEL_MUX_LISTENER	15	/* Listener for mux conn. */
+#define SSH_CHANNEL_MUX_CLIENT		16	/* Conn. to mux client */
+#define SSH_CHANNEL_ABANDONED		17	/* Abandoned session, eg mux */
+#define SSH_CHANNEL_UNIX_LISTENER	18	/* Listening on a domain socket. */
+#define SSH_CHANNEL_RUNIX_LISTENER	19	/* Listening to a R-style domain socket. */
+#define SSH_CHANNEL_MUX_PROXY		20	/* proxy channel for mux-client */
+#define SSH_CHANNEL_RDYNAMIC_OPEN	21	/* reverse SOCKS, parsing request */
+#define SSH_CHANNEL_RDYNAMIC_FINISH	22	/* reverse SOCKS, finishing connect */
+#define SSH_CHANNEL_MAX_TYPE		23
+
+#define CHANNEL_CANCEL_PORT_STATIC	-1
+
+/* TCP forwarding */
+#define FORWARD_DENY		0
+#define FORWARD_REMOTE		(1)
+#define FORWARD_LOCAL		(1<<1)
+#define FORWARD_ALLOW		(FORWARD_REMOTE|FORWARD_LOCAL)
+
+#define FORWARD_ADM		0x100
+#define FORWARD_USER		0x101
+
+struct ssh;
+struct Channel;
+typedef struct Channel Channel;
+struct fwd_perm_list;
+
+typedef void channel_open_fn(struct ssh *, int, int, void *);
+typedef void channel_callback_fn(struct ssh *, int, void *);
+typedef int channel_infilter_fn(struct ssh *, struct Channel *, char *, int);
+typedef void channel_filter_cleanup_fn(struct ssh *, int, void *);
+typedef u_char *channel_outfilter_fn(struct ssh *, struct Channel *,
+    u_char **, size_t *);
+
+/* Channel success/failure callbacks */
+typedef void channel_confirm_cb(struct ssh *, int, struct Channel *, void *);
+typedef void channel_confirm_abandon_cb(struct ssh *, struct Channel *, void *);
+struct channel_confirm {
+	TAILQ_ENTRY(channel_confirm) entry;
+	channel_confirm_cb *cb;
+	channel_confirm_abandon_cb *abandon_cb;
+	void *ctx;
+};
+TAILQ_HEAD(channel_confirms, channel_confirm);
+
+/* Context for non-blocking connects */
+struct channel_connect {
+	char *host;
+	int port;
+	struct addrinfo *ai, *aitop;
+};
+
+/* Callbacks for mux channels back into client-specific code */
+typedef int mux_callback_fn(struct ssh *, struct Channel *);
+
+/*
+ * NB. channel IDs on the wire and in c->remote_id are uint32, but local
+ * channel IDs (e.g. c->self) only ever use the int32 subset of this range,
+ * because we use local channel ID -1 for housekeeping. Remote channels have
+ * a dedicated "have_remote_id" flag to indicate their validity.
+ */
+
+struct Channel {
+	int     type;		/* channel type/state */
+
+	int     self;		/* my own channel identifier */
+	uint32_t remote_id;	/* channel identifier for remote peer */
+	int	have_remote_id;	/* non-zero if remote_id is valid */
+
+	u_int   istate;		/* input from channel (state of receive half) */
+	u_int   ostate;		/* output to channel  (state of transmit half) */
+	int     flags;		/* close sent/rcvd */
+	int     rfd;		/* read fd */
+	int     wfd;		/* write fd */
+	int     efd;		/* extended fd */
+	int     sock;		/* sock fd */
+	int     ctl_chan;	/* control channel (multiplexed connections) */
+	int     isatty;		/* rfd is a tty */
+#ifdef _AIX
+	int     wfd_isatty;	/* wfd is a tty */
+#endif
+	int	client_tty;	/* (client) TTY has been requested */
+	int     force_drain;	/* force close on iEOF */
+	time_t	notbefore;	/* Pause IO until deadline (time_t) */
+	int     delayed;	/* post-select handlers for newly created
+				 * channels are delayed until the first call
+				 * to a matching pre-select handler.
+				 * this way post-select handlers are not
+				 * accidentally called if a FD gets reused */
+	struct sshbuf *input;	/* data read from socket, to be sent over
+				 * encrypted connection */
+	struct sshbuf *output;	/* data received over encrypted connection for
+				 * send on socket */
+	struct sshbuf *extended;
+
+	char    *path;
+		/* path for unix domain sockets, or host name for forwards */
+	int     listening_port;	/* port being listened for forwards */
+	char   *listening_addr;	/* addr being listened for forwards */
+	int     host_port;	/* remote port to connect for forwards */
+	char   *remote_name;	/* remote hostname */
+
+	u_int	remote_window;
+	u_int	remote_maxpacket;
+	u_int	local_window;
+	u_int	local_window_max;
+	u_int	local_consumed;
+	u_int	local_maxpacket;
+	int     extended_usage;
+	int	single_connection;
+
+	char   *ctype;		/* type */
+
+	/* callback */
+	channel_open_fn		*open_confirm;
+	void			*open_confirm_ctx;
+	channel_callback_fn	*detach_user;
+	int			detach_close;
+	struct channel_confirms	status_confirms;
+
+	/* filter */
+	channel_infilter_fn	*input_filter;
+	channel_outfilter_fn	*output_filter;
+	void			*filter_ctx;
+	channel_filter_cleanup_fn *filter_cleanup;
+
+	/* keep boundaries */
+	int     		datagram;
+
+	/* non-blocking connect */
+	/* XXX make this a pointer so the structure can be opaque */
+	struct channel_connect	connect_ctx;
+
+	/* multiplexing protocol hook, called for each packet received */
+	mux_callback_fn		*mux_rcb;
+	void			*mux_ctx;
+	int			mux_pause;
+	int     		mux_downstream_id;
+};
+
+#define CHAN_EXTENDED_IGNORE		0
+#define CHAN_EXTENDED_READ		1
+#define CHAN_EXTENDED_WRITE		2
+
+/* default window/packet sizes for tcp/x11-fwd-channel */
+#define CHAN_SES_PACKET_DEFAULT	(32*1024)
+#define CHAN_SES_WINDOW_DEFAULT	(64*CHAN_SES_PACKET_DEFAULT)
+#define CHAN_TCP_PACKET_DEFAULT	(32*1024)
+#define CHAN_TCP_WINDOW_DEFAULT	(64*CHAN_TCP_PACKET_DEFAULT)
+#define CHAN_X11_PACKET_DEFAULT	(16*1024)
+#define CHAN_X11_WINDOW_DEFAULT	(4*CHAN_X11_PACKET_DEFAULT)
+
+/* possible input states */
+#define CHAN_INPUT_OPEN			0
+#define CHAN_INPUT_WAIT_DRAIN		1
+#define CHAN_INPUT_WAIT_OCLOSE		2
+#define CHAN_INPUT_CLOSED		3
+
+/* possible output states */
+#define CHAN_OUTPUT_OPEN		0
+#define CHAN_OUTPUT_WAIT_DRAIN		1
+#define CHAN_OUTPUT_WAIT_IEOF		2
+#define CHAN_OUTPUT_CLOSED		3
+
+#define CHAN_CLOSE_SENT			0x01
+#define CHAN_CLOSE_RCVD			0x02
+#define CHAN_EOF_SENT			0x04
+#define CHAN_EOF_RCVD			0x08
+#define CHAN_LOCAL			0x10
+
+/* Read buffer size */
+#define CHAN_RBUF	(16*1024)
+
+/* Maximum channel input buffer size */
+#define CHAN_INPUT_MAX	(16*1024*1024)
+
+/* Hard limit on number of channels */
+#define CHANNELS_MAX_CHANNELS	(16*1024)
+
+/* check whether 'efd' is still in use */
+#define CHANNEL_EFD_INPUT_ACTIVE(c) \
+	(c->extended_usage == CHAN_EXTENDED_READ && \
+	(c->efd != -1 || \
+	sshbuf_len(c->extended) > 0))
+#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
+	(c->extended_usage == CHAN_EXTENDED_WRITE && \
+	c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \
+	sshbuf_len(c->extended) > 0))
+
+/* Add channel management structures to SSH transport instance */
+void channel_init_channels(struct ssh *ssh);
+
+/* channel management */
+
+Channel	*channel_by_id(struct ssh *, int);
+Channel	*channel_by_remote_id(struct ssh *, u_int);
+Channel	*channel_lookup(struct ssh *, int);
+Channel *channel_new(struct ssh *, char *, int, int, int, int,
+	    u_int, u_int, int, char *, int);
+void	 channel_set_fds(struct ssh *, int, int, int, int, int,
+	    int, int, u_int);
+void	 channel_free(struct ssh *, Channel *);
+void	 channel_free_all(struct ssh *);
+void	 channel_stop_listening(struct ssh *);
+
+void	 channel_send_open(struct ssh *, int);
+void	 channel_request_start(struct ssh *, int, char *, int);
+void	 channel_register_cleanup(struct ssh *, int,
+	    channel_callback_fn *, int);
+void	 channel_register_open_confirm(struct ssh *, int,
+	    channel_open_fn *, void *);
+void	 channel_register_filter(struct ssh *, int, channel_infilter_fn *,
+	    channel_outfilter_fn *, channel_filter_cleanup_fn *, void *);
+void	 channel_register_status_confirm(struct ssh *, int,
+	    channel_confirm_cb *, channel_confirm_abandon_cb *, void *);
+void	 channel_cancel_cleanup(struct ssh *, int);
+int	 channel_close_fd(struct ssh *, int *);
+void	 channel_send_window_changes(struct ssh *);
+
+/* mux proxy support */
+
+int	 channel_proxy_downstream(struct ssh *, Channel *mc);
+int	 channel_proxy_upstream(Channel *, int, u_int32_t, struct ssh *);
+
+/* protocol handler */
+
+int	 channel_input_data(int, u_int32_t, struct ssh *);
+int	 channel_input_extended_data(int, u_int32_t, struct ssh *);
+int	 channel_input_ieof(int, u_int32_t, struct ssh *);
+int	 channel_input_oclose(int, u_int32_t, struct ssh *);
+int	 channel_input_open_confirmation(int, u_int32_t, struct ssh *);
+int	 channel_input_open_failure(int, u_int32_t, struct ssh *);
+int	 channel_input_port_open(int, u_int32_t, struct ssh *);
+int	 channel_input_window_adjust(int, u_int32_t, struct ssh *);
+int	 channel_input_status_confirm(int, u_int32_t, struct ssh *);
+
+/* file descriptor handling (read/write) */
+
+void	 channel_prepare_select(struct ssh *, fd_set **, fd_set **, int *,
+	     u_int*, time_t*);
+void     channel_after_select(struct ssh *, fd_set *, fd_set *);
+void     channel_output_poll(struct ssh *);
+
+int      channel_not_very_much_buffered_data(struct ssh *);
+void     channel_close_all(struct ssh *);
+int      channel_still_open(struct ssh *);
+const char *channel_format_extended_usage(const Channel *);
+char	*channel_open_message(struct ssh *);
+int	 channel_find_open(struct ssh *);
+
+/* tcp forwarding */
+struct Forward;
+struct ForwardOptions;
+void	 channel_set_af(struct ssh *, int af);
+void     channel_permit_all(struct ssh *, int);
+void	 channel_add_permission(struct ssh *, int, int, char *, int);
+void	 channel_clear_permission(struct ssh *, int, int);
+void	 channel_disable_admin(struct ssh *, int);
+void	 channel_update_permission(struct ssh *, int, int);
+Channel	*channel_connect_to_port(struct ssh *, const char *, u_short,
+	    char *, char *, int *, const char **);
+Channel *channel_connect_to_path(struct ssh *, const char *, char *, char *);
+Channel	*channel_connect_stdio_fwd(struct ssh *, const char*,
+	    u_short, int, int);
+Channel	*channel_connect_by_listen_address(struct ssh *, const char *,
+	    u_short, char *, char *);
+Channel	*channel_connect_by_listen_path(struct ssh *, const char *,
+	    char *, char *);
+int	 channel_request_remote_forwarding(struct ssh *, struct Forward *);
+int	 channel_setup_local_fwd_listener(struct ssh *, struct Forward *,
+	    struct ForwardOptions *);
+int	 channel_request_rforward_cancel(struct ssh *, struct Forward *);
+int	 channel_setup_remote_fwd_listener(struct ssh *, struct Forward *,
+	    int *, struct ForwardOptions *);
+int	 channel_cancel_rport_listener(struct ssh *, struct Forward *);
+int	 channel_cancel_lport_listener(struct ssh *, struct Forward *,
+	    int, struct ForwardOptions *);
+int	 permitopen_port(const char *);
+
+/* x11 forwarding */
+
+void	 channel_set_x11_refuse_time(struct ssh *, u_int);
+int	 x11_connect_display(struct ssh *);
+int	 x11_create_display_inet(struct ssh *, int, int, int, u_int *, int **);
+void	 x11_request_forwarding_with_spoofing(struct ssh *, int,
+	    const char *, const char *, const char *, int);
+
+/* channel close */
+
+int	 chan_is_dead(struct ssh *, Channel *, int);
+void	 chan_mark_dead(struct ssh *, Channel *);
+
+/* channel events */
+
+void	 chan_rcvd_oclose(struct ssh *, Channel *);
+void	 chan_rcvd_eow(struct ssh *, Channel *);
+void	 chan_read_failed(struct ssh *, Channel *);
+void	 chan_ibuf_empty(struct ssh *, Channel *);
+void	 chan_rcvd_ieof(struct ssh *, Channel *);
+void	 chan_write_failed(struct ssh *, Channel *);
+void	 chan_obuf_empty(struct ssh *, Channel *);
+
+#endif