diff options
| -rw-r--r-- | ChangeLog | 4 | ||||
| -rw-r--r-- | channels.c | 896 | ||||
| -rw-r--r-- | channels.h | 185 |
3 files changed, 518 insertions, 567 deletions
@@ -12,6 +12,8 @@ packet.c serverloop.c session.c ssh.c] undo the .c file split, just merge the header and keep the cvs history + - (bal) Channels.c and Channels.h -- "Merge Functions, simplify" (draged + out of ssh Attic) 20010606 - OpenBSD CVS Sync @@ -5523,4 +5525,4 @@ - Wrote replacements for strlcpy and mkdtemp - Released 1.0pre1 -$Id: ChangeLog,v 1.1249 2001/06/09 00:36:26 mouring Exp $ +$Id: ChangeLog,v 1.1250 2001/06/09 00:41:05 mouring Exp $ @@ -40,33 +40,24 @@ */ #include "includes.h" -RCSID("$OpenBSD: channels.c,v 1.119 2001/05/28 23:25:24 markus Exp $"); - -#include <openssl/rsa.h> -#include <openssl/dsa.h> +RCSID("$OpenBSD: channels.c,v 1.121 2001/05/31 10:30:14 markus Exp $"); #include "ssh.h" #include "ssh1.h" #include "ssh2.h" #include "packet.h" #include "xmalloc.h" -#include "buffer.h" -#include "bufaux.h" #include "uidswap.h" #include "log.h" #include "misc.h" #include "channels.h" -#include "nchan.h" #include "compat.h" #include "canohost.h" #include "key.h" #include "authfd.h" -/* Maximum number of fake X11 displays to try. */ -#define MAX_DISPLAYS 1000 -/* Max len of agent socket */ -#define MAX_SOCKET_NAME 100 +/* -- channel core */ /* * Pointer to an array containing all allocated channels. The array is @@ -86,23 +77,8 @@ static int channels_alloc = 0; */ static int channel_max_fd = 0; -/* Name and directory of socket for authentication agent forwarding. */ -static char *channel_forwarded_auth_socket_name = NULL; -static char *channel_forwarded_auth_socket_dir = NULL; - -/* Saved X11 authentication protocol name. */ -char *x11_saved_proto = NULL; - -/* Saved X11 authentication data. This is the real data. */ -char *x11_saved_data = NULL; -u_int x11_saved_data_len = 0; -/* - * Fake X11 authentication data. This is what the server will be sending us; - * we should replace any occurrences of this by the real data. - */ -char *x11_fake_data = NULL; -u_int x11_fake_data_len; +/* -- tcp forwarding */ /* * Data structure for storing which hosts are permitted for forward requests. @@ -118,6 +94,7 @@ typedef struct { /* List of all permitted host/port pairs to connect. */ static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; + /* Number of permitted host/port pairs in the array. */ static int num_permitted_opens = 0; /* @@ -127,23 +104,43 @@ static int num_permitted_opens = 0; */ static int all_opens_permitted = 0; -/* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */ -static int have_hostname_in_open = 0; -/* AF_UNSPEC or AF_INET or AF_INET6 */ -extern int IPv4or6; +/* -- X11 forwarding */ -void port_open_helper(Channel *c, char *rtype); +/* Maximum number of fake X11 displays to try. */ +#define MAX_DISPLAYS 1000 -/* Sets specific protocol options. */ +/* Saved X11 authentication protocol name. */ +static char *x11_saved_proto = NULL; -void -channel_set_options(int hostname_in_open) -{ - have_hostname_in_open = hostname_in_open; -} +/* Saved X11 authentication data. This is the real data. */ +static char *x11_saved_data = NULL; +static u_int x11_saved_data_len = 0; -/* lookup channel by id */ +/* + * Fake X11 authentication data. This is what the server will be sending us; + * we should replace any occurrences of this by the real data. + */ +static char *x11_fake_data = NULL; +static u_int x11_fake_data_len; + + +/* -- agent forwarding */ + +#define NUM_SOCKS 10 + +/* Name and directory of socket for authentication agent forwarding. */ +static char *auth_sock_name = NULL; +static char *auth_sock_dir = NULL; + + +/* AF_UNSPEC or AF_INET or AF_INET6 */ +extern int IPv4or6; + +/* helper */ +void port_open_helper(Channel *c, char *rtype); + +/* -- channel core */ Channel * channel_lookup(int id) @@ -337,6 +334,321 @@ channel_free(Channel *c) xfree(c); } + +/* + * Stops listening for channels, and removes any unix domain sockets that we + * might have. + */ + +void +channel_stop_listening() +{ + int i; + Channel *c; + + for (i = 0; i < channels_alloc; i++) { + c = channels[i]; + if (c != NULL) { + switch (c->type) { + case SSH_CHANNEL_AUTH_SOCKET: + close(c->sock); + unlink(c->path); + channel_free(c); + break; + case SSH_CHANNEL_PORT_LISTENER: + case SSH_CHANNEL_RPORT_LISTENER: + case SSH_CHANNEL_X11_LISTENER: + close(c->sock); + channel_free(c); + break; + default: + break; + } + } + } +} + +/* + * Closes the sockets/fds of all channels. This is used to close extra file + * descriptors after a fork. + */ + +void +channel_close_all() +{ + int i; + + for (i = 0; i < channels_alloc; i++) + if (channels[i] != NULL) + channel_close_fds(channels[i]); +} + +/* + * Returns true if no channel has too much buffered data, and false if one or + * more channel is overfull. + */ + +int +channel_not_very_much_buffered_data() +{ + u_int i; + Channel *c; + + for (i = 0; i < channels_alloc; i++) { + c = channels[i]; + if (c != NULL && c->type == SSH_CHANNEL_OPEN) { + if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { + debug("channel %d: big input buffer %d", + c->self, buffer_len(&c->input)); + return 0; + } + if (buffer_len(&c->output) > packet_get_maxsize()) { + debug("channel %d: big output buffer %d", + c->self, buffer_len(&c->output)); + return 0; + } + } + } + return 1; +} + +/* Returns true if any channel is still open. */ + +int +channel_still_open() +{ + int i; + Channel *c; + + for (i = 0; i < channels_alloc; i++) { + c = channels[i]; + if (c == NULL) + continue; + switch (c->type) { + case SSH_CHANNEL_X11_LISTENER: + case SSH_CHANNEL_PORT_LISTENER: + case SSH_CHANNEL_RPORT_LISTENER: + case SSH_CHANNEL_CLOSED: + case SSH_CHANNEL_AUTH_SOCKET: + case SSH_CHANNEL_DYNAMIC: + case SSH_CHANNEL_CONNECTING: + case SSH_CHANNEL_ZOMBIE: + continue; + case SSH_CHANNEL_LARVAL: + if (!compat20) + fatal("cannot happen: SSH_CHANNEL_LARVAL"); + continue; + case SSH_CHANNEL_OPENING: + case SSH_CHANNEL_OPEN: + case SSH_CHANNEL_X11_OPEN: + return 1; + case SSH_CHANNEL_INPUT_DRAINING: + case SSH_CHANNEL_OUTPUT_DRAINING: + if (!compat13) + fatal("cannot happen: OUT_DRAIN"); + return 1; + default: + fatal("channel_still_open: bad channel type %d", c->type); + /* NOTREACHED */ + } + } + return 0; +} + +/* Returns the id of an open channel suitable for keepaliving */ + +int +channel_find_open() +{ + int i; + Channel *c; + + for (i = 0; i < channels_alloc; i++) { + c = channels[i]; + if (c == NULL) + continue; + switch (c->type) { + case SSH_CHANNEL_CLOSED: + case SSH_CHANNEL_DYNAMIC: + case SSH_CHANNEL_X11_LISTENER: + case SSH_CHANNEL_PORT_LISTENER: + case SSH_CHANNEL_RPORT_LISTENER: + case SSH_CHANNEL_OPENING: + case SSH_CHANNEL_CONNECTING: + case SSH_CHANNEL_ZOMBIE: + continue; + case SSH_CHANNEL_LARVAL: + case SSH_CHANNEL_AUTH_SOCKET: + case SSH_CHANNEL_OPEN: + case SSH_CHANNEL_X11_OPEN: + return i; + case SSH_CHANNEL_INPUT_DRAINING: + case SSH_CHANNEL_OUTPUT_DRAINING: + if (!compat13) + fatal("cannot happen: OUT_DRAIN"); + return i; + default: + fatal("channel_find_open: bad channel type %d", c->type); + /* NOTREACHED */ + } + } + return -1; +} + + +/* + * Returns a message describing the currently open forwarded connections, + * suitable for sending to the client. The message contains crlf pairs for + * newlines. + */ + +char * +channel_open_message() +{ + Buffer buffer; + Channel *c; + char buf[1024], *cp; + int i; + + buffer_init(&buffer); + snprintf(buf, sizeof buf, "The following connections are open:\r\n"); + buffer_append(&buffer, buf, strlen(buf)); + for (i = 0; i < channels_alloc; i++) { + c = channels[i]; + if (c == NULL) + continue; + switch (c->type) { + case SSH_CHANNEL_X11_LISTENER: + case SSH_CHANNEL_PORT_LISTENER: + case SSH_CHANNEL_RPORT_LISTENER: + case SSH_CHANNEL_CLOSED: + case SSH_CHANNEL_AUTH_SOCKET: + case SSH_CHANNEL_ZOMBIE: + continue; + case SSH_CHANNEL_LARVAL: + case SSH_CHANNEL_OPENING: + case SSH_CHANNEL_CONNECTING: + case SSH_CHANNEL_DYNAMIC: + case SSH_CHANNEL_OPEN: + case SSH_CHANNEL_X11_OPEN: + case SSH_CHANNEL_INPUT_DRAINING: + case SSH_CHANNEL_OUTPUT_DRAINING: + snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", + c->self, c->remote_name, + c->type, c->remote_id, + c->istate, buffer_len(&c->input), + c->ostate, buffer_len(&c->output), + c->rfd, c->wfd); + buffer_append(&buffer, buf, strlen(buf)); + continue; + default: + fatal("channel_open_message: bad channel type %d", c->type); + /* NOTREACHED */ + } + } + buffer_append(&buffer, "\0", 1); + cp = xstrdup(buffer_ptr(&buffer)); + buffer_free(&buffer); + return cp; +} + +void +channel_send_open(int id) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_send_open: %d: bad id", id); + return; + } + debug("send channel open %d", id); + packet_start(SSH2_MSG_CHANNEL_OPEN); + packet_put_cstring(c->ctype); + packet_put_int(c->self); + packet_put_int(c->local_window); + packet_put_int(c->local_maxpacket); + packet_send(); +} + +void +channel_request(int id, char *service, int wantconfirm) +{ + channel_request_start(id, service, wantconfirm); + packet_send(); + debug("channel request %d: %s", id, service) ; +} +void +channel_request_start(int id, char *service, int wantconfirm) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_request: %d: bad id", id); + return; + } + packet_start(SSH2_MSG_CHANNEL_REQUEST); + packet_put_int(c->remote_id); + packet_put_cstring(service); + packet_put_char(wantconfirm); +} +void +channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_register_callback: %d: bad id", id); + return; + } + c->cb_event = mtype; + c->cb_fn = fn; + c->cb_arg = arg; +} +void +channel_register_cleanup(int id, channel_callback_fn *fn) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_register_cleanup: %d: bad id", id); + return; + } + c->dettach_user = fn; +} +void +channel_cancel_cleanup(int id) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_cancel_cleanup: %d: bad id", id); + return; + } + c->dettach_user = NULL; +} +void +channel_register_filter(int id, channel_filter_fn *fn) +{ + Channel *c = channel_lookup(id); + if (c == NULL) { + log("channel_register_filter: %d: bad id", id); + return; + } + c->input_filter = fn; +} + +void +channel_set_fds(int id, int rfd, int wfd, int efd, + int extusage, int nonblock) +{ + Channel *c = channel_lookup(id); + if (c == NULL || c->type != SSH_CHANNEL_LARVAL) + fatal("channel_activate for non-larval channel %d.", id); + channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); + c->type = SSH_CHANNEL_OPEN; + /* XXX window size? */ + c->local_window = c->local_window_max = c->local_maxpacket * 2; + packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); + packet_put_int(c->remote_id); + packet_put_int(c->local_window); + packet_send(); +} + /* * 'channel_pre*' are called just before select() to add any bits relevant to * channels in the select bitmasks. @@ -442,19 +754,20 @@ channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) * data in that packet is then substituted by the real data if it matches the * fake data, and the channel is put into normal mode. * XXX All this happens at the client side. + * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok */ int -x11_open_helper(Channel *c) +x11_open_helper(Buffer *b) { u_char *ucp; u_int proto_len, data_len; /* Check if the fixed size part of the packet is in buffer. */ - if (buffer_len(&c->output) < 12) + if (buffer_len(b) < 12) return 0; /* Parse the lengths of variable-length fields. */ - ucp = (u_char *) buffer_ptr(&c->output); + ucp = (u_char *) buffer_ptr(b); if (ucp[0] == 0x42) { /* Byte order MSB first. */ proto_len = 256 * ucp[6] + ucp[7]; data_len = 256 * ucp[8] + ucp[9]; @@ -468,7 +781,7 @@ x11_open_helper(Channel *c) } /* Check if the whole packet is in buffer. */ - if (buffer_len(&c->output) < + if (buffer_len(b) < 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) return 0; @@ -504,7 +817,7 @@ x11_open_helper(Channel *c) void channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) { - int ret = x11_open_helper(c); + int ret = x11_open_helper(&c->output); if (ret == 1) { /* Start normal processing for the channel. */ c->type = SSH_CHANNEL_OPEN; @@ -529,7 +842,7 @@ channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) void channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) { - int ret = x11_open_helper(c); + int ret = x11_open_helper(&c->output); if (ret == 1) { c->type = SSH_CHANNEL_OPEN; if (compat20) @@ -704,7 +1017,8 @@ channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) } else { packet_start(SSH_SMSG_X11_OPEN); packet_put_int(nc->self); - if (have_hostname_in_open) + if (packet_get_protocol_flags() & + SSH_PROTOFLAG_HOST_IN_FWD_OPEN) packet_put_string(buf, strlen(buf)); packet_send(); } @@ -755,7 +1069,8 @@ port_open_helper(Channel *c, char *rtype) packet_put_int(c->self); packet_put_cstring(c->path); packet_put_int(c->host_port); - if (have_hostname_in_open) + if (packet_get_protocol_flags() & + SSH_PROTOFLAG_HOST_IN_FWD_OPEN) packet_put_cstring(c->remote_name); packet_send(); } @@ -817,6 +1132,7 @@ void channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) { Channel *nc; + char *name; int newsock; struct sockaddr addr; socklen_t addrlen; @@ -828,12 +1144,14 @@ channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) error("accept from auth socket: %.100s", strerror(errno)); return; } + name = xstrdup("accepted auth socket"); nc = channel_new("accepted auth socket", SSH_CHANNEL_OPENING, newsock, newsock, -1, c->local_window_max, c->local_maxpacket, - 0, xstrdup("accepted auth socket"), 1); + 0, name, 1); if (nc == NULL) { error("channel_post_auth_listener: channel_new failed"); + xfree(name); close(newsock); } if (compat20) { @@ -918,7 +1236,7 @@ channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) } else if (compat13) { buffer_consume(&c->output, buffer_len(&c->output)); c->type = SSH_CHANNEL_INPUT_DRAINING; - debug("channel %d: status set to input draining.", c->self); + debug("channel %d: input draining.", c->self); } else { chan_read_failed(c); } @@ -956,7 +1274,7 @@ channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) return -1; } else if (compat13) { buffer_consume(&c->output, buffer_len(&c->output)); - debug("channel %d: status set to input draining.", c->self); + debug("channel %d: input draining.", c->self); c->type = SSH_CHANNEL_INPUT_DRAINING; } else { chan_write_failed(c); @@ -1196,6 +1514,10 @@ channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) } } +/* + * Allocate/update select bitmasks and add any bits relevant to channels in + * select bitmasks. + */ void channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, int rekeying) @@ -1222,12 +1544,17 @@ channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, channel_handler(channel_pre, *readsetp, *writesetp); } +/* + * After select, perform any appropriate operations for channels which have + * events pending. + */ void channel_after_select(fd_set * readset, fd_set * writeset) { channel_handler(channel_post, readset, writeset); } + /* If there is data to send to the connection, enqueue some of it now. */ void @@ -1237,12 +1564,14 @@ channel_output_poll() Channel *c; for (i = 0; i < channels_alloc; i++) { - c = channels[i]; if (c == NULL) continue; - /* We are only interested in channels that can have buffered incoming data. */ + /* + * We are only interested in channels that can have buffered + * incoming data. + */ if (compat13) { if (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_INPUT_DRAINING) @@ -1262,7 +1591,10 @@ channel_output_poll() if ((c->istate == CHAN_INPUT_OPEN || c->istate == CHAN_INPUT_WAIT_DRAIN) && (len = buffer_len(&c->input)) > 0) { - /* Send some data for the other side over the secure connection. */ + /* + * Send some data for the other side over the secure + * connection. + */ if (compat20) { if (len > c->remote_window) len = c->remote_window; @@ -1320,11 +1652,8 @@ channel_output_poll() } } -/* - * This is called when a packet of type CHANNEL_DATA has just been received. - * The message type has already been consumed, but channel number and data is - * still there. - */ + +/* -- protocol input */ void channel_input_data(int type, int plen, void *ctxt) @@ -1371,6 +1700,7 @@ channel_input_data(int type, int plen, void *ctxt) buffer_append(&c->output, data, data_len); xfree(data); } + void channel_input_extended_data(int type, int plen, void *ctxt) { @@ -1411,36 +1741,6 @@ channel_input_extended_data(int type, int plen, void *ctxt) xfree(data); } - -/* - * Returns true if no channel has too much buffered data, and false if one or - * more channel is overfull. - */ - -int -channel_not_very_much_buffered_data() -{ - u_int i; - Channel *c; - - for (i = 0; i < channels_alloc; i++) { - c = channels[i]; - if (c != NULL && c->type == SSH_CHANNEL_OPEN) { - if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { - debug("channel %d: big input buffer %d", - c->self, buffer_len(&c->input)); - return 0; - } - if (buffer_len(&c->output) > packet_get_maxsize()) { - debug("channel %d: big output buffer %d", - c->self, buffer_len(&c->output)); - return 0; - } - } - } - return 1; -} - void channel_input_ieof(int type, int plen, void *ctxt) { @@ -1655,193 +1955,46 @@ channel_input_window_adjust(int type, int plen, void *ctxt) c->remote_window += adjust; } -/* - * Stops listening for channels, and removes any unix domain sockets that we - * might have. - */ - -void -channel_stop_listening() -{ - int i; - Channel *c; - - for (i = 0; i < channels_alloc; i++) { - c = channels[i]; - if (c != NULL) { - switch (c->type) { - case SSH_CHANNEL_AUTH_SOCKET: - close(c->sock); - unlink(c->path); - channel_free(c); - break; - case SSH_CHANNEL_PORT_LISTENER: - case SSH_CHANNEL_RPORT_LISTENER: - case SSH_CHANNEL_X11_LISTENER: - close(c->sock); - channel_free(c); - break; - default: - break; - } - } - } -} - -/* - * Closes the sockets/fds of all channels. This is used to close extra file - * descriptors after a fork. - */ - void -channel_close_all() +channel_input_port_open(int type, int plen, void *ctxt) { - int i; - - for (i = 0; i < channels_alloc; i++) - if (channels[i] != NULL) - channel_close_fds(channels[i]); -} - -/* Returns true if any channel is still open. */ + Channel *c = NULL; + u_short host_port; + char *host, *originator_string; + int remote_id, sock = -1; -int -channel_still_open() -{ - int i; - Channel *c; + remote_id = packet_get_int(); + host = packet_get_string(NULL); + host_port = packet_get_int(); - for (i = 0; i < channels_alloc; i++) { - c = channels[i]; - if (c == NULL) - continue; - switch (c->type) { - case SSH_CHANNEL_X11_LISTENER: - case SSH_CHANNEL_PORT_LISTENER: - case SSH_CHANNEL_RPORT_LISTENER: - case SSH_CHANNEL_CLOSED: - case SSH_CHANNEL_AUTH_SOCKET: - case SSH_CHANNEL_DYNAMIC: - case SSH_CHANNEL_CONNECTING: - case SSH_CHANNEL_ZOMBIE: - continue; - case SSH_CHANNEL_LARVAL: - if (!compat20) - fatal("cannot happen: SSH_CHANNEL_LARVAL"); - continue; - case SSH_CHANNEL_OPENING: - case SSH_CHANNEL_OPEN: - case SSH_CHANNEL_X11_OPEN: - return 1; - case SSH_CHANNEL_INPUT_DRAINING: - case SSH_CHANNEL_OUTPUT_DRAINING: - if (!compat13) - fatal("cannot happen: OUT_DRAIN"); - return 1; - default: - fatal("channel_still_open: bad channel type %d", c->type); - /* NOTREACHED */ - } + if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { + originator_string = packet_get_string(NULL); + } else { + originator_string = xstrdup("unknown (remote did not supply name)"); } - return 0; -} - -/* Returns the id of an open channel suitable for keepaliving */ - -int -channel_find_open() -{ - int i; - Channel *c; - - for (i = 0; i < channels_alloc; i++) { - c = channels[i]; - if (c == NULL) - continue; - switch (c->type) { - case SSH_CHANNEL_CLOSED: - case SSH_CHANNEL_DYNAMIC: - case SSH_CHANNEL_X11_LISTENER: - case SSH_CHANNEL_PORT_LISTENER: - case SSH_CHANNEL_RPORT_LISTENER: - case SSH_CHANNEL_OPENING: - case SSH_CHANNEL_CONNECTING: - case SSH_CHANNEL_ZOMBIE: - continue; - case SSH_CHANNEL_LARVAL: - case SSH_CHANNEL_AUTH_SOCKET: - case SSH_CHANNEL_OPEN: - case SSH_CHANNEL_X11_OPEN: - return i; - case SSH_CHANNEL_INPUT_DRAINING: - case SSH_CHANNEL_OUTPUT_DRAINING: - if (!compat13) - fatal("cannot happen: OUT_DRAIN"); - return i; - default: - fatal("channel_find_open: bad channel type %d", c->type); - /* NOTREACHED */ + packet_done(); + sock = channel_connect_to(host, host_port); + if (sock != -1) { + c = channel_new("connected socket", + SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, + originator_string, 1); + if (c == NULL) { + error("channel_input_port_open: channel_new failed"); + close(sock); + } else { + c->remote_id = remote_id; } } - return -1; + if (c == NULL) { + packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); + packet_put_int(remote_id); + packet_send(); + } + xfree(host); } -/* - * Returns a message describing the currently open forwarded connections, - * suitable for sending to the client. The message contains crlf pairs for - * newlines. - */ - -char * -channel_open_message() -{ - Buffer buffer; - Channel *c; - char buf[1024], *cp; - int i; - - buffer_init(&buffer); - snprintf(buf, sizeof buf, "The following connections are open:\r\n"); - buffer_append(&buffer, buf, strlen(buf)); - for (i = 0; i < channels_alloc; i++) { - c = channels[i]; - if (c == NULL) - continue; - switch (c->type) { - case SSH_CHANNEL_X11_LISTENER: - case SSH_CHANNEL_PORT_LISTENER: - case SSH_CHANNEL_RPORT_LISTENER: - case SSH_CHANNEL_CLOSED: - case SSH_CHANNEL_AUTH_SOCKET: - case SSH_CHANNEL_ZOMBIE: - continue; - case SSH_CHANNEL_LARVAL: - case SSH_CHANNEL_OPENING: - case SSH_CHANNEL_CONNECTING: - case SSH_CHANNEL_DYNAMIC: - case SSH_CHANNEL_OPEN: - case SSH_CHANNEL_X11_OPEN: - case SSH_CHANNEL_INPUT_DRAINING: - case SSH_CHANNEL_OUTPUT_DRAINING: - snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", - c->self, c->remote_name, - c->type, c->remote_id, - c->istate, buffer_len(&c->input), - c->ostate, buffer_len(&c->output), - c->rfd, c->wfd); - buffer_append(&buffer, buf, strlen(buf)); - continue; - default: - fatal("channel_open_message: bad channel type %d", c->type); - /* NOTREACHED */ - } - } - buffer_append(&buffer, "\0", 1); - cp = xstrdup(buffer_ptr(&buffer)); - buffer_free(&buffer); - return cp; -} +/* -- tcp forwarding */ /* * Initiate forwarding of connections to local port "port" through the secure @@ -1868,7 +2021,7 @@ channel_request_forwarding( int gateway_ports, int remote_fwd) { Channel *c; - int success, sock, on = 1, ctype; + int success, sock, on = 1, type; struct addrinfo hints, *ai, *aitop; char ntop[NI_MAXHOST], strport[NI_MAXSERV]; const char *host; @@ -1878,10 +2031,10 @@ channel_request_forwarding( if (remote_fwd) { host = listen_address; - ctype = SSH_CHANNEL_RPORT_LISTENER; + type = SSH_CHANNEL_RPORT_LISTENER; } else { host = host_to_connect; - ctype =SSH_CHANNEL_PORT_LISTENER; + type = SSH_CHANNEL_PORT_LISTENER; } if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { @@ -1945,7 +2098,7 @@ channel_request_forwarding( continue; } /* Allocate a channel number for the socket. */ - c = channel_new("port listener", ctype, sock, sock, -1, + c = channel_new("port listener", type, sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("port listener"), 1); if (c == NULL) { @@ -2183,58 +2336,13 @@ channel_connect_to(const char *host, u_short port) return connect_to(host, port); } -/* - * This is called after receiving PORT_OPEN message. This attempts to - * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION - * or CHANNEL_OPEN_FAILURE. - */ - -void -channel_input_port_open(int type, int plen, void *ctxt) -{ - Channel *c = NULL; - u_short host_port; - char *host, *originator_string; - int remote_id, sock = -1; - - remote_id = packet_get_int(); - host = packet_get_string(NULL); - host_port = packet_get_int(); - - if (have_hostname_in_open) { - originator_string = packet_get_string(NULL); - } else { - originator_string = xstrdup("unknown (remote did not supply name)"); - } - packet_done(); - sock = channel_connect_to(host, host_port); - if (sock != -1) { - c = channel_new("connected socket", - SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, - originator_string, 1); - if (c == NULL) { - error("channel_input_port_open: channel_new failed"); - close(sock); - } else { - c->remote_id = remote_id; - } - } - if (c == NULL) { - packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); - packet_put_int(remote_id); - packet_send(); - } - xfree(host); -} +/* -- X11 forwarding */ /* * Creates an internet domain socket for listening for X11 connections. * Returns a suitable value for the DISPLAY variable, or NULL if an error * occurs. */ - -#define NUM_SOCKS 10 - char * x11_create_display_inet(int screen_number, int x11_display_offset) { @@ -2515,7 +2623,8 @@ x11_input_open(int type, int plen, void *ctxt) debug("Received X11 open request."); remote_id = packet_get_int(); - if (have_hostname_in_open) { + + if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { remote_host = packet_get_string(NULL); } else { remote_host = xstrdup("unknown (remote did not supply name)"); @@ -2574,8 +2683,8 @@ deny_input_open(int type, int plen, void *ctxt) /* * Requests forwarding of X11 connections, generates fake authentication * data, and enables authentication spoofing. + * This should be called in the client only. */ - void x11_request_forwarding_with_spoofing(int client_session_id, const char *proto, const char *data) @@ -2640,6 +2749,9 @@ x11_request_forwarding_with_spoofing(int client_session_id, xfree(new_data); } + +/* -- agent forwarding */ + /* Sends a message to the server to request authentication fd forwarding. */ void @@ -2659,7 +2771,7 @@ auth_request_forwarding() char * auth_get_socket_name() { - return channel_forwarded_auth_socket_name; + return auth_sock_name; } /* removes the agent forwarding socket */ @@ -2667,8 +2779,8 @@ auth_get_socket_name() void cleanup_socket(void) { - unlink(channel_forwarded_auth_socket_name); - rmdir(channel_forwarded_auth_socket_dir); + unlink(auth_sock_name); + rmdir(auth_sock_dir); } /* @@ -2683,30 +2795,32 @@ auth_input_request_forwarding(struct passwd * pw) int sock; struct sockaddr_un sunaddr; - if (auth_get_socket_name() != NULL) - fatal("Protocol error: authentication forwarding requested twice."); + if (auth_get_socket_name() != NULL) { + error("authentication forwarding requested twice."); + return 0; + } /* Temporarily drop privileged uid for mkdir/bind. */ temporarily_use_uid(pw); /* Allocate a buffer for the socket name, and format the name. */ - channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME); - channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME); - strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME); + auth_sock_name = xmalloc(MAXPATHLEN); + auth_sock_dir = xmalloc(MAXPATHLEN); + strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); /* Create private directory for socket */ - if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) { - packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s", - strerror(errno)); + if (mkdtemp(auth_sock_dir) == NULL) { + packet_send_debug("Agent forwarding disabled: " + "mkdtemp() failed: %.100s", strerror(errno)); restore_uid(); - xfree(channel_forwarded_auth_socket_name); - xfree(channel_forwarded_auth_socket_dir); - channel_forwarded_auth_socket_name = NULL; - channel_forwarded_auth_socket_dir = NULL; + xfree(auth_sock_name); + xfree(auth_sock_dir); + auth_sock_name = NULL; + auth_sock_dir = NULL; return 0; } - snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d", - channel_forwarded_auth_socket_dir, (int) getpid()); + snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", + auth_sock_dir, (int) getpid()); if (atexit(cleanup_socket) < 0) { int saved = errno; @@ -2721,7 +2835,7 @@ auth_input_request_forwarding(struct passwd * pw) /* Bind it to the name. */ memset(&sunaddr, 0, sizeof(sunaddr)); sunaddr.sun_family = AF_UNIX; - strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name, + strncpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) @@ -2744,7 +2858,7 @@ auth_input_request_forwarding(struct passwd * pw) close(sock); return 0; } - strlcpy(nc->path, channel_forwarded_auth_socket_name, sizeof(nc->path)); + strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); return 1; } @@ -2755,7 +2869,7 @@ auth_input_open_request(int type, int plen, void *ctxt) { Channel *c = NULL; int remote_id, sock; - char *dummyname; + char *name; packet_integrity_check(plen, 4, type); @@ -2775,10 +2889,12 @@ auth_input_open_request(int type, int plen, void *ctxt) * agent. */ if (sock >= 0) { - dummyname = xstrdup("authentication agent connection"); - c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, -1, 0, 0, 0, dummyname, 1); + name = xstrdup("authentication agent connection"); + c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, + -1, 0, 0, 0, name, 1); if (c == NULL) { error("auth_input_open_request: channel_new failed"); + xfree(name); close(sock); } else { c->remote_id = remote_id; @@ -2796,105 +2912,3 @@ auth_input_open_request(int type, int plen, void *ctxt) } packet_send(); } - -void -channel_start_open(int id) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_open: %d: bad id", id); - return; - } - debug("send channel open %d", id); - packet_start(SSH2_MSG_CHANNEL_OPEN); - packet_put_cstring(c->ctype); - packet_put_int(c->self); - packet_put_int(c->local_window); - packet_put_int(c->local_maxpacket); -} -void -channel_open(int id) -{ - /* XXX REMOVE ME */ - channel_start_open(id); - packet_send(); -} -void -channel_request(int id, char *service, int wantconfirm) -{ - channel_request_start(id, service, wantconfirm); - packet_send(); - debug("channel request %d: %s", id, service) ; -} -void -channel_request_start(int id, char *service, int wantconfirm) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_request: %d: bad id", id); - return; - } - packet_start(SSH2_MSG_CHANNEL_REQUEST); - packet_put_int(c->remote_id); - packet_put_cstring(service); - packet_put_char(wantconfirm); -} -void -channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_register_callback: %d: bad id", id); - return; - } - c->cb_event = mtype; - c->cb_fn = fn; - c->cb_arg = arg; -} -void -channel_register_cleanup(int id, channel_callback_fn *fn) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_register_cleanup: %d: bad id", id); - return; - } - c->dettach_user = fn; -} -void -channel_cancel_cleanup(int id) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_cancel_cleanup: %d: bad id", id); - return; - } - c->dettach_user = NULL; -} -void -channel_register_filter(int id, channel_filter_fn *fn) -{ - Channel *c = channel_lookup(id); - if (c == NULL) { - log("channel_register_filter: %d: bad id", id); - return; - } - c->input_filter = fn; -} - -void -channel_set_fds(int id, int rfd, int wfd, int efd, - int extusage, int nonblock) -{ - Channel *c = channel_lookup(id); - if (c == NULL || c->type != SSH_CHANNEL_LARVAL) - fatal("channel_activate for non-larval channel %d.", id); - channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); - c->type = SSH_CHANNEL_OPEN; - /* XXX window size? */ - c->local_window = c->local_window_max = c->local_maxpacket * 2; - packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); - packet_put_int(c->remote_id); - packet_put_int(c->local_window); - packet_send(); -} @@ -32,10 +32,10 @@ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ -/* RCSID("$OpenBSD: channels.h,v 1.33 2001/05/28 23:14:49 markus Exp $"); */ +/* RCSID("$OpenBSD: channels.h,v 1.35 2001/05/31 10:30:15 markus Exp $"); */ -#ifndef CHANNELS_H -#define CHANNELS_H +#ifndef CHANNEL_H +#define CHANNEL_H #include "buffer.h" @@ -124,21 +124,42 @@ struct Channel { #define CHAN_X11_WINDOW_DEFAULT (4*1024) #define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2) +/* possible input states */ +#define CHAN_INPUT_OPEN 0x01 +#define CHAN_INPUT_WAIT_DRAIN 0x02 +#define CHAN_INPUT_WAIT_OCLOSE 0x04 +#define CHAN_INPUT_CLOSED 0x08 -void channel_open(int id); +/* possible output states */ +#define CHAN_OUTPUT_OPEN 0x10 +#define CHAN_OUTPUT_WAIT_DRAIN 0x20 +#define CHAN_OUTPUT_WAIT_IEOF 0x40 +#define CHAN_OUTPUT_CLOSED 0x80 + +#define CHAN_CLOSE_SENT 0x01 +#define CHAN_CLOSE_RCVD 0x02 + + +/* channel management */ + +Channel *channel_lookup(int id); +Channel * +channel_new(char *ctype, int type, int rfd, int wfd, int efd, + int window, int maxpack, int extusage, char *remote_name, int nonblock); +void +channel_set_fds(int id, int rfd, int wfd, int efd, + int extusage, int nonblock); +void channel_free(Channel *c); + +void channel_send_open(int id); void channel_request(int id, char *service, int wantconfirm); void channel_request_start(int id, char *service, int wantconfirm); void channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg); void channel_register_cleanup(int id, channel_callback_fn *fn); void channel_register_filter(int id, channel_filter_fn *fn); void channel_cancel_cleanup(int id); -Channel *channel_lookup(int id); -void -channel_set_fds(int id, int rfd, int wfd, int efd, - int extusage, int nonblock); - -void deny_input_open(int type, int plen, void *ctxt); +/* protocol handler */ void channel_input_channel_request(int type, int plen, void *ctxt); void channel_input_close(int type, int plen, void *ctxt); @@ -152,66 +173,22 @@ void channel_input_open_failure(int type, int plen, void *ctxt); void channel_input_port_open(int type, int plen, void *ctxt); void channel_input_window_adjust(int type, int plen, void *ctxt); -/* Sets specific protocol options. */ -void channel_set_options(int hostname_in_open); - -/* - * Allocate a new channel object and set its type and socket. Remote_name - * must have been allocated with xmalloc; this will free it when the channel - * is freed. - */ -Channel * -channel_new(char *ctype, int type, int rfd, int wfd, int efd, - int window, int maxpack, int extended_usage, char *remote_name, - int nonblock); - -/* Free the channel and close its socket. */ -void channel_free(Channel *c); +/* file descriptor handling (read/write) */ -/* - * Allocate/update select bitmasks and add any bits relevant to channels in - * select bitmasks. - */ void channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, int rekeying); - -/* - * After select, perform any appropriate operations for channels which have - * events pending. - */ void channel_after_select(fd_set * readset, fd_set * writeset); - -/* If there is data to send to the connection, send some of it now. */ void channel_output_poll(void); -/* Returns true if no channel has too much buffered data. */ int channel_not_very_much_buffered_data(void); - -/* This closes any sockets that are listening for connections; this removes - any unix domain sockets. */ void channel_stop_listening(void); - -/* - * Closes the sockets of all channels. This is used to close extra file - * descriptors after a fork. - */ void channel_close_all(void); - -/* Returns true if there is still an open channel over the connection. */ int channel_still_open(void); - -/* - * Returns a string containing a list of all open channels. The list is - * suitable for displaying to the user. It uses crlf instead of newlines. - * The caller should free the string with xfree. - */ char *channel_open_message(void); +int channel_find_open(void); -/* - * Initiate forwarding of connections to local port "port" through the secure - * channel to host:port from remote side. - */ +/* channel_tcpfwd.c */ int channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, u_short port_to_connect, int gateway_ports); @@ -219,95 +196,53 @@ int channel_request_forwarding(const char *listen_address, u_short listen_port, const char *host_to_connect, u_short port_to_connect, int gateway_ports, int remote_fwd); - -/* - * Initiate forwarding of connections to port "port" on remote host through - * the secure channel to host:port from local side. This never returns if - * there was an error. This registers that open requests for that port are - * permitted. - */ void channel_request_remote_forwarding(u_short port, const char *host, u_short remote_port); - -/* - * Permits opening to any host/port if permitted_opens[] is empty. This is - * usually called by the server, because the user could connect to any port - * anyway, and the server has no way to know but to trust the client anyway. - */ void channel_permit_all_opens(void); - -/* Add host/port to list of allowed targets for port forwarding */ void channel_add_permitted_opens(char *host, int port); - -/* Flush list */ void channel_clear_permitted_opens(void); - -/* - * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates - * listening for the port, and sends back a success reply (or disconnect - * message if there was an error). This never returns if there was an error. - */ void channel_input_port_forward_request(int is_root, int gateway_ports); +int channel_connect_to(const char *host, u_short host_port); +int channel_connect_by_listen_adress(u_short listen_port); -/* - * Creates a port for X11 connections, and starts listening for it. Returns - * the display name, or NULL if an error was encountered. - */ -char *x11_create_display(int screen); +/* x11 forwarding */ -/* - * Creates an internet domain socket for listening for X11 connections. - * Returns a suitable value for the DISPLAY variable, or NULL if an error - * occurs. - */ +int x11_connect_display(void); +//int x11_check_cookie(Buffer *b); +char *x11_create_display(int screen); char *x11_create_display_inet(int screen, int x11_display_offset); - -/* - * This is called when SSH_SMSG_X11_OPEN is received. The packet contains - * the remote channel number. We should do whatever we want, and respond - * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. - */ void x11_input_open(int type, int plen, void *ctxt); - -/* - * Requests forwarding of X11 connections. This should be called on the - * client only. - */ void x11_request_forwarding(void); - -/* - * Requests forwarding for X11 connections, with authentication spoofing. - * This should be called in the client only. - */ void x11_request_forwarding_with_spoofing(int client_session_id, const char *proto, const char *data); +void deny_input_open(int type, int plen, void *ctxt); -/* Sends a message to the server to request authentication fd forwarding. */ -void auth_request_forwarding(void); +/* agent forwarding */ -/* - * Returns the name of the forwarded authentication socket. Returns NULL if - * there is no forwarded authentication socket. The returned value points to - * a static buffer. - */ +void auth_request_forwarding(void); char *auth_get_socket_name(void); - -/* - * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. - * This starts forwarding authentication requests. - */ int auth_input_request_forwarding(struct passwd * pw); - -/* This is called to process an SSH_SMSG_AGENT_OPEN message. */ void auth_input_open_request(int type, int plen, void *ctxt); -/* XXX */ -int channel_connect_to(const char *host, u_short host_port); -int channel_connect_by_listen_adress(u_short listen_port); -int x11_connect_display(void); +/* channel close */ -int channel_find_open(void); +typedef void chan_event_fn(Channel * c); + +/* for the input state */ +extern chan_event_fn *chan_rcvd_oclose; +extern chan_event_fn *chan_read_failed; +extern chan_event_fn *chan_ibuf_empty; + +/* for the output state */ +extern chan_event_fn *chan_rcvd_ieof; +extern chan_event_fn *chan_write_failed; +extern chan_event_fn *chan_obuf_empty; + +int chan_is_dead(Channel * c); +void chan_mark_dead(Channel * c); +void chan_init_iostates(Channel * c); +void chan_init(void); #endif |