1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
#ifndef PUTTY_SSH2CONNECTION_H
#define PUTTY_SSH2CONNECTION_H
struct outstanding_channel_request;
struct outstanding_global_request;
struct ssh2_connection_state {
int crState;
ssh_sharing_state *connshare;
char *peer_verstring;
mainchan *mainchan;
SshChannel *mainchan_sc;
bool ldisc_opts[LD_N_OPTIONS];
int session_attempt, session_status;
int term_width, term_height;
bool want_user_input;
bufchain *user_input;
bool ssh_is_simple;
bool persistent;
bool started;
Conf *conf;
tree234 *channels; /* indexed by local id */
bool all_channels_throttled;
bool X11_fwd_enabled;
tree234 *x11authtree;
bool got_pty;
tree234 *rportfwds;
PortFwdManager *portfwdmgr;
bool portfwdmgr_configured;
prompts_t *antispoof_prompt;
SeatPromptResult antispoof_ret;
const SftpServerVtable *sftpserver_vt;
const SshServerConfig *ssc;
/*
* These store the list of global requests that we're waiting for
* replies to. (REQUEST_FAILURE doesn't come with any indication
* of what message caused it, so we have to keep track of the
* queue ourselves.)
*/
struct outstanding_global_request *globreq_head, *globreq_tail;
ConnectionLayer cl;
PacketProtocolLayer ppl;
};
typedef void (*gr_handler_fn_t)(struct ssh2_connection_state *s,
PktIn *pktin, void *ctx);
void ssh2_queue_global_request_handler(
struct ssh2_connection_state *s, gr_handler_fn_t handler, void *ctx);
struct ssh2_channel {
struct ssh2_connection_state *connlayer;
unsigned remoteid, localid;
int type;
/* True if we opened this channel but server hasn't confirmed. */
bool halfopen;
/* Bitmap of whether we've sent/received CHANNEL_EOF and
* CHANNEL_CLOSE. */
#define CLOSES_SENT_EOF 1
#define CLOSES_SENT_CLOSE 2
#define CLOSES_RCVD_EOF 4
#define CLOSES_RCVD_CLOSE 8
int closes;
/*
* This flag indicates that an EOF is pending on the outgoing side
* of the channel: that is, wherever we're getting the data for
* this channel has sent us some data followed by EOF. We can't
* actually send the EOF until we've finished sending the data, so
* we set this flag instead to remind us to do so once our buffer
* is clear.
*/
bool pending_eof;
/*
* True if this channel is causing the underlying connection to be
* throttled.
*/
bool throttling_conn;
/*
* True if we currently have backed-up data on the direction of
* this channel pointing out of the SSH connection, and therefore
* would prefer the 'Channel' implementation not to read further
* local input if possible.
*/
bool throttled_by_backlog;
bufchain outbuffer, errbuffer;
unsigned remwindow, remmaxpkt;
/* locwindow is signed so we can cope with excess data. */
int locwindow, locmaxwin;
/*
* remlocwin is the amount of local window that we think
* the remote end had available to it after it sent the
* last data packet or window adjust ack.
*/
int remlocwin;
/*
* These store the list of channel requests that we're waiting for
* replies to. (CHANNEL_FAILURE doesn't come with any indication
* of what message caused it, so we have to keep track of the
* queue ourselves.)
*/
struct outstanding_channel_request *chanreq_head, *chanreq_tail;
enum { THROTTLED, UNTHROTTLING, UNTHROTTLED } throttle_state;
ssh_sharing_connstate *sharectx; /* sharing context, if this is a
* downstream channel */
Channel *chan; /* handle the client side of this channel, if not */
SshChannel sc; /* entry point for chan to talk back to */
};
typedef void (*cr_handler_fn_t)(struct ssh2_channel *, PktIn *, void *);
void ssh2_channel_init(struct ssh2_channel *c);
PktOut *ssh2_chanreq_init(struct ssh2_channel *c, const char *type,
cr_handler_fn_t handler, void *ctx);
typedef enum ChanopenOutcome {
CHANOPEN_RESULT_FAILURE,
CHANOPEN_RESULT_SUCCESS,
CHANOPEN_RESULT_DOWNSTREAM,
} ChanopenOutcome;
typedef struct ChanopenResult {
ChanopenOutcome outcome;
union {
struct {
char *wire_message; /* must be freed by recipient */
unsigned reason_code;
} failure;
struct {
Channel *channel;
} success;
struct {
ssh_sharing_connstate *share_ctx;
} downstream;
} u;
} ChanopenResult;
PktOut *ssh2_chanopen_init(struct ssh2_channel *c, const char *type);
PktOut *ssh2_portfwd_chanopen(
struct ssh2_connection_state *s, struct ssh2_channel *c,
const char *hostname, int port,
const char *description, const SocketPeerInfo *peerinfo);
struct ssh_rportfwd *ssh2_rportfwd_alloc(
ConnectionLayer *cl,
const char *shost, int sport, const char *dhost, int dport,
int addressfamily, const char *log_description, PortFwdRecord *pfr,
ssh_sharing_connstate *share_ctx);
void ssh2_rportfwd_remove(
ConnectionLayer *cl, struct ssh_rportfwd *rpf);
SshChannel *ssh2_session_open(ConnectionLayer *cl, Channel *chan);
SshChannel *ssh2_serverside_x11_open(
ConnectionLayer *cl, Channel *chan, const SocketPeerInfo *pi);
SshChannel *ssh2_serverside_agent_open(ConnectionLayer *cl, Channel *chan);
void ssh2channel_send_exit_status(SshChannel *c, int status);
void ssh2channel_send_exit_signal(
SshChannel *c, ptrlen signame, bool core_dumped, ptrlen msg);
void ssh2channel_send_exit_signal_numeric(
SshChannel *c, int signum, bool core_dumped, ptrlen msg);
void ssh2channel_request_x11_forwarding(
SshChannel *c, bool want_reply, const char *authproto,
const char *authdata, int screen_number, bool oneshot);
void ssh2channel_request_agent_forwarding(SshChannel *c, bool want_reply);
void ssh2channel_request_pty(
SshChannel *c, bool want_reply, Conf *conf, int w, int h);
bool ssh2channel_send_env_var(
SshChannel *c, bool want_reply, const char *var, const char *value);
void ssh2channel_start_shell(SshChannel *c, bool want_reply);
void ssh2channel_start_command(
SshChannel *c, bool want_reply, const char *command);
bool ssh2channel_start_subsystem(
SshChannel *c, bool want_reply, const char *subsystem);
bool ssh2channel_send_env_var(
SshChannel *c, bool want_reply, const char *var, const char *value);
bool ssh2channel_send_serial_break(
SshChannel *c, bool want_reply, int length);
bool ssh2channel_send_signal(
SshChannel *c, bool want_reply, const char *signame);
void ssh2channel_send_terminal_size_change(SshChannel *c, int w, int h);
#define CHANOPEN_RETURN_FAILURE(code, msgparams) do \
{ \
ChanopenResult toret; \
toret.outcome = CHANOPEN_RESULT_FAILURE; \
toret.u.failure.reason_code = code; \
toret.u.failure.wire_message = dupprintf msgparams; \
return toret; \
} while (0)
#define CHANOPEN_RETURN_SUCCESS(chan) do \
{ \
ChanopenResult toret; \
toret.outcome = CHANOPEN_RESULT_SUCCESS; \
toret.u.success.channel = chan; \
return toret; \
} while (0)
#define CHANOPEN_RETURN_DOWNSTREAM(shctx) do \
{ \
ChanopenResult toret; \
toret.outcome = CHANOPEN_RESULT_DOWNSTREAM; \
toret.u.downstream.share_ctx = shctx; \
return toret; \
} while (0)
ChanopenResult ssh2_connection_parse_channel_open(
struct ssh2_connection_state *s, ptrlen type,
PktIn *pktin, SshChannel *sc);
bool ssh2_connection_parse_global_request(
struct ssh2_connection_state *s, ptrlen type, PktIn *pktin);
bool ssh2_connection_need_antispoof_prompt(struct ssh2_connection_state *s);
#endif /* PUTTY_SSH2CONNECTION_H */
|
