diff options
Diffstat (limited to 'channels.h')
-rw-r--r-- | channels.h | 244 |
1 files changed, 141 insertions, 103 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: channels.h,v 1.116 2015/01/19 20:07:45 markus Exp $ */ +/* $OpenBSD: channels.h,v 1.133 2020/01/25 22:49:38 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> @@ -46,8 +46,6 @@ #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_INPUT_DRAINING 8 /* sending remaining data to conn */ -#define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ #define SSH_CHANNEL_LARVAL 10 /* larval session */ #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */ #define SSH_CHANNEL_CONNECTING 12 @@ -58,22 +56,37 @@ #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_MAX_TYPE 20 +#define SSH_CHANNEL_MUX_PROXY 20 /* proxy channel for mux-slave */ +#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(int, int, void *); -typedef void channel_callback_fn(int, void *); -typedef int channel_infilter_fn(struct Channel *, char *, int); -typedef void channel_filter_cleanup_fn(int, void *); -typedef u_char *channel_outfilter_fn(struct Channel *, u_char **, u_int *); +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(int, struct Channel *, void *); -typedef void channel_confirm_abandon_cb(struct Channel *, void *); +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; @@ -90,12 +103,22 @@ struct channel_connect { }; /* Callbacks for mux channels back into client-specific code */ -typedef int mux_callback_fn(struct Channel *); +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 */ - int remote_id; /* channel identifier for remote peer */ + 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 */ @@ -113,14 +136,15 @@ struct Channel { 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. + * to a matching pre-select handler. * this way post-select handlers are not * accidentally called if a FD gets reused */ - Buffer input; /* data read from socket, to be sent over + struct sshbuf *input; /* data read from socket, to be sent over * encrypted connection */ - Buffer output; /* data received over encrypted connection for + struct sshbuf *output; /* data received over encrypted connection for * send on socket */ - Buffer extended; + struct sshbuf *extended; + char *path; /* path for unix domain sockets, or host name for forwards */ int listening_port; /* port being listened for forwards */ @@ -156,12 +180,14 @@ struct Channel { 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 @@ -194,121 +220,133 @@ struct Channel { #define CHAN_EOF_RCVD 0x08 #define CHAN_LOCAL 0x10 -#define CHAN_RBUF 16*1024 +/* Read buffer size */ +#define CHAN_RBUF (16*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) \ - (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \ + (c->extended_usage == CHAN_EXTENDED_READ && \ (c->efd != -1 || \ - buffer_len(&c->extended) > 0)) + sshbuf_len(c->extended) > 0)) #define CHANNEL_EFD_OUTPUT_ACTIVE(c) \ - (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \ + (c->extended_usage == CHAN_EXTENDED_WRITE && \ c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \ - buffer_len(&c->extended) > 0)) + 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(int); -Channel *channel_lookup(int); -Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int); -void channel_set_fds(int, int, int, int, int, int, int, u_int); -void channel_free(Channel *); -void channel_free_all(void); -void channel_stop_listening(void); - -void channel_send_open(int); -void channel_request_start(int, char *, int); -void channel_register_cleanup(int, channel_callback_fn *, int); -void channel_register_open_confirm(int, channel_open_fn *, void *); -void channel_register_filter(int, channel_infilter_fn *, - channel_outfilter_fn *, channel_filter_cleanup_fn *, void *); -void channel_register_status_confirm(int, channel_confirm_cb *, - channel_confirm_abandon_cb *, void *); -void channel_cancel_cleanup(int); -int channel_close_fd(int *); -void channel_send_window_changes(void); +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_close(int, u_int32_t, void *); -int channel_input_close_confirmation(int, u_int32_t, void *); -int channel_input_data(int, u_int32_t, void *); -int channel_input_extended_data(int, u_int32_t, void *); -int channel_input_ieof(int, u_int32_t, void *); -int channel_input_oclose(int, u_int32_t, void *); -int channel_input_open_confirmation(int, u_int32_t, void *); -int channel_input_open_failure(int, u_int32_t, void *); -int channel_input_port_open(int, u_int32_t, void *); -int channel_input_window_adjust(int, u_int32_t, void *); -int channel_input_status_confirm(int, u_int32_t, void *); +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(fd_set **, fd_set **, int *, u_int*, - time_t*, int); -void channel_after_select(fd_set *, fd_set *); -void channel_output_poll(void); +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(void); -void channel_close_all(void); -int channel_still_open(void); -char *channel_open_message(void); -int channel_find_open(void); +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(int af); -void channel_permit_all_opens(void); -void channel_add_permitted_opens(char *, int); -int channel_add_adm_permitted_opens(char *, int); -void channel_disable_adm_local_opens(void); -void channel_update_permitted_opens(int, int); -void channel_clear_permitted_opens(void); -void channel_clear_adm_permitted_opens(void); -void channel_print_adm_permitted_opens(void); -int channel_input_port_forward_request(int, struct ForwardOptions *); -Channel *channel_connect_to_port(const char *, u_short, char *, char *); -Channel *channel_connect_to_path(const char *, char *, char *); -Channel *channel_connect_stdio_fwd(const char*, u_short, int, int); -Channel *channel_connect_by_listen_address(const char *, u_short, - char *, char *); -Channel *channel_connect_by_listen_path(const char *, char *, char *); -int channel_request_remote_forwarding(struct Forward *); -int channel_setup_local_fwd_listener(struct Forward *, struct ForwardOptions *); -int channel_request_rforward_cancel(struct Forward *); -int channel_setup_remote_fwd_listener(struct Forward *, int *, struct ForwardOptions *); -int channel_cancel_rport_listener(struct Forward *); -int channel_cancel_lport_listener(struct Forward *, int, 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 */ -int x11_connect_display(void); -int x11_create_display_inet(int, int, int, u_int *, int **); -int x11_input_open(int, u_int32_t, void *); -void x11_request_forwarding_with_spoofing(int, const char *, const char *, - const char *, int); -int deny_input_open(int, u_int32_t, void *); - -/* agent forwarding */ - -void auth_request_forwarding(void); +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(Channel *, int); -void chan_mark_dead(Channel *); +int chan_is_dead(struct ssh *, Channel *, int); +void chan_mark_dead(struct ssh *, Channel *); /* channel events */ -void chan_rcvd_oclose(Channel *); -void chan_rcvd_eow(Channel *); /* SSH2-only */ -void chan_read_failed(Channel *); -void chan_ibuf_empty(Channel *); - -void chan_rcvd_ieof(Channel *); -void chan_write_failed(Channel *); -void chan_obuf_empty(Channel *); +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 |