2 * Terminal 3270 implementation
4 * Copyright 2017 IBM Corp.
6 * Authors: Yang Chen <bjcyang@linux.vnet.ibm.com>
7 * Jing Liu <liujbjl@linux.vnet.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2 or (at
10 * your option) any later version. See the COPYING file in the top-level
14 #include "qemu/osdep.h"
15 #include "qapi/error.h"
16 #include "qemu/module.h"
17 #include "chardev/char-fe.h"
18 #include "hw/qdev-properties.h"
19 #include "hw/s390x/3270-ccw.h"
20 #include "qom/object.h"
22 /* Enough spaces for different window sizes. */
23 #define INPUT_BUFFER_SIZE 1000
25 * 1 for header, 1024*2 for datastream, 2 for tail
26 * Reserve enough spaces for telnet IAC escape.
28 #define OUTPUT_BUFFER_SIZE 2051
31 EmulatedCcw3270Device cdev
;
33 uint8_t inv
[INPUT_BUFFER_SIZE
];
34 uint8_t outv
[OUTPUT_BUFFER_SIZE
];
39 typedef struct Terminal3270 Terminal3270
;
41 #define TYPE_TERMINAL_3270 "x-terminal3270"
42 DECLARE_INSTANCE_CHECKER(Terminal3270
, TERMINAL_3270
,
45 static int terminal_can_read(void *opaque
)
47 Terminal3270
*t
= opaque
;
49 return INPUT_BUFFER_SIZE
- t
->in_len
;
52 static void terminal_timer_cancel(Terminal3270
*t
)
55 g_source_remove(t
->timer_tag
);
61 * Protocol handshake done,
62 * signal guest by an unsolicited DE irq.
64 static void TN3270_handshake_done(Terminal3270
*t
)
66 CcwDevice
*ccw_dev
= CCW_DEVICE(t
);
67 SubchDev
*sch
= ccw_dev
->sch
;
69 t
->handshake_done
= true;
70 sch
->curr_status
.scsw
.dstat
= SCSW_DSTAT_DEVICE_END
;
71 css_conditional_io_interrupt(sch
);
75 * Called when the interval is timeout to detect
76 * if the client is still alive by Timing Mark.
78 static gboolean
send_timing_mark_cb(gpointer opaque
)
80 Terminal3270
*t
= opaque
;
81 const uint8_t timing
[] = {0xff, 0xfd, 0x06};
83 qemu_chr_fe_write_all(&t
->chr
, timing
, sizeof(timing
));
88 * Receive inbound data from socket.
89 * For data given to guest, drop the data boundary IAC, IAC_EOR.
91 * Using "Reset" key on x3270 may result multiple commands in one packet.
92 * This usually happens when the user meets a poor traffic of the network.
93 * As of now, for such case, we simply terminate the connection,
94 * and we should come back here later with a better solution.
96 static void terminal_read(void *opaque
, const uint8_t *buf
, int size
)
98 Terminal3270
*t
= opaque
;
99 CcwDevice
*ccw_dev
= CCW_DEVICE(t
);
100 SubchDev
*sch
= ccw_dev
->sch
;
103 assert(size
<= (INPUT_BUFFER_SIZE
- t
->in_len
));
105 terminal_timer_cancel(t
);
106 t
->timer_tag
= g_timeout_add_seconds(600, send_timing_mark_cb
, t
);
107 memcpy(&t
->inv
[t
->in_len
], buf
, size
);
113 if (!t
->handshake_done
) {
115 * Receiving Terminal Type is the last step of handshake.
116 * The data format: IAC SB Terminal-Type IS <terminal type> IAC SE
117 * The code for Terminal-Type is 0x18, for IS is 0.
118 * Simply check the data format and mark handshake_done.
120 if (t
->in_len
> 6 && t
->inv
[2] == 0x18 && t
->inv
[3] == 0x0 &&
121 t
->inv
[t
->in_len
- 2] == IAC
&& t
->inv
[t
->in_len
- 1] == IAC_SE
) {
122 TN3270_handshake_done(t
);
128 for (end
= 0; end
< t
->in_len
- 1; end
++) {
129 if (t
->inv
[end
] == IAC
&& t
->inv
[end
+ 1] == IAC_EOR
) {
133 if (end
== t
->in_len
- 2) {
134 /* Data is valid for consuming. */
136 sch
->curr_status
.scsw
.dstat
= SCSW_DSTAT_ATTENTION
;
137 css_conditional_io_interrupt(sch
);
138 } else if (end
< t
->in_len
- 2) {
139 /* "Reset" key is used. */
140 qemu_chr_fe_disconnect(&t
->chr
);
142 /* Gathering data. */
147 static void chr_event(void *opaque
, QEMUChrEvent event
)
149 Terminal3270
*t
= opaque
;
150 CcwDevice
*ccw_dev
= CCW_DEVICE(t
);
151 SubchDev
*sch
= ccw_dev
->sch
;
153 /* Ensure the initial status correct, always reset them. */
155 t
->handshake_done
= false;
156 terminal_timer_cancel(t
);
159 case CHR_EVENT_OPENED
:
161 * 3270 does handshake firstly by the negotiate options in
162 * char-socket.c. Once qemu receives the terminal-type of the
163 * client, mark handshake done and trigger everything rolling again.
165 t
->timer_tag
= g_timeout_add_seconds(600, send_timing_mark_cb
, t
);
167 case CHR_EVENT_CLOSED
:
168 sch
->curr_status
.scsw
.dstat
= SCSW_DSTAT_DEVICE_END
;
169 css_conditional_io_interrupt(sch
);
171 case CHR_EVENT_BREAK
:
172 case CHR_EVENT_MUX_IN
:
173 case CHR_EVENT_MUX_OUT
:
179 static void terminal_init(EmulatedCcw3270Device
*dev
, Error
**errp
)
181 Terminal3270
*t
= TERMINAL_3270(dev
);
182 static bool terminal_available
;
184 if (terminal_available
) {
185 error_setg(errp
, "Multiple 3270 terminals are not supported.");
188 terminal_available
= true;
189 qemu_chr_fe_set_handlers(&t
->chr
, terminal_can_read
,
190 terminal_read
, chr_event
, NULL
, t
, NULL
, true);
193 static inline CcwDataStream
*get_cds(Terminal3270
*t
)
195 return &(CCW_DEVICE(&t
->cdev
)->sch
->cds
);
198 static int read_payload_3270(EmulatedCcw3270Device
*dev
)
200 Terminal3270
*t
= TERMINAL_3270(dev
);
203 len
= MIN(ccw_dstream_avail(get_cds(t
)), t
->in_len
);
204 ccw_dstream_write_buf(get_cds(t
), t
->inv
, len
);
210 /* TN3270 uses binary transmission, which needs escape IAC to IAC IAC */
211 static int insert_IAC_escape_char(uint8_t *outv
, int out_len
)
213 int IAC_num
= 0, new_out_len
, i
, j
;
215 for (i
= 0; i
< out_len
; i
++) {
216 if (outv
[i
] == IAC
) {
223 new_out_len
= out_len
+ IAC_num
;
224 for (i
= out_len
- 1, j
= new_out_len
- 1; j
> i
&& i
>= 0; i
--, j
--) {
226 if (outv
[i
] == IAC
) {
234 * Write 3270 outbound to socket.
235 * Return the count of 3270 data field if succeeded, zero if failed.
237 static int write_payload_3270(EmulatedCcw3270Device
*dev
, uint8_t cmd
)
239 Terminal3270
*t
= TERMINAL_3270(dev
);
241 int count
= ccw_dstream_avail(get_cds(t
));
242 int bound
= (OUTPUT_BUFFER_SIZE
- 3) / 2;
243 int len
= MIN(count
, bound
);
246 if (!t
->handshake_done
) {
247 if (!(t
->outv
[0] == IAC
&& t
->outv
[1] != IAC
)) {
249 * Before having finished 3270 negotiation,
250 * sending outbound data except protocol options is prohibited.
255 if (!qemu_chr_fe_backend_connected(&t
->chr
)) {
256 /* We just say we consumed all data if there's no backend. */
260 t
->outv
[out_len
++] = cmd
;
262 ccw_dstream_read_buf(get_cds(t
), &t
->outv
[out_len
], len
);
263 count
= ccw_dstream_avail(get_cds(t
));
266 out_len
= insert_IAC_escape_char(t
->outv
, out_len
);
268 t
->outv
[out_len
++] = IAC
;
269 t
->outv
[out_len
++] = IAC_EOR
;
271 retval
= qemu_chr_fe_write_all(&t
->chr
, t
->outv
, out_len
);
272 len
= MIN(count
, bound
);
274 } while (len
&& retval
>= 0);
275 return (retval
<= 0) ? 0 : get_cds(t
)->count
;
278 static Property terminal_properties
[] = {
279 DEFINE_PROP_CHR("chardev", Terminal3270
, chr
),
280 DEFINE_PROP_END_OF_LIST(),
283 static const VMStateDescription terminal3270_vmstate
= {
284 .name
= TYPE_TERMINAL_3270
,
288 static void terminal_class_init(ObjectClass
*klass
, void *data
)
290 DeviceClass
*dc
= DEVICE_CLASS(klass
);
291 EmulatedCcw3270Class
*ck
= EMULATED_CCW_3270_CLASS(klass
);
293 device_class_set_props(dc
, terminal_properties
);
294 dc
->vmsd
= &terminal3270_vmstate
;
295 ck
->init
= terminal_init
;
296 ck
->read_payload_3270
= read_payload_3270
;
297 ck
->write_payload_3270
= write_payload_3270
;
300 static const TypeInfo ccw_terminal_info
= {
301 .name
= TYPE_TERMINAL_3270
,
302 .parent
= TYPE_EMULATED_CCW_3270
,
303 .instance_size
= sizeof(Terminal3270
),
304 .class_init
= terminal_class_init
,
305 .class_size
= sizeof(EmulatedCcw3270Class
),
308 static void register_types(void)
310 type_register_static(&ccw_terminal_info
);
313 type_init(register_types
)