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
|
/*
* Terminal 3270 implementation
*
* Copyright 2017 IBM Corp.
*
* Authors: Yang Chen <bjcyang@linux.vnet.ibm.com>
* Jing Liu <liujbjl@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "sysemu/char.h"
#include "hw/s390x/3270-ccw.h"
/* Enough spaces for different window sizes. */
#define INPUT_BUFFER_SIZE 1000
/*
* 1 for header, 1024*2 for datastream, 2 for tail
* Reserve enough spaces for telnet IAC escape.
*/
#define OUTPUT_BUFFER_SIZE 2051
typedef struct Terminal3270 {
EmulatedCcw3270Device cdev;
CharBackend chr;
uint8_t inv[INPUT_BUFFER_SIZE];
uint8_t outv[OUTPUT_BUFFER_SIZE];
int in_len;
int out_len;
bool handshake_done;
} Terminal3270;
#define TYPE_TERMINAL_3270 "x-terminal3270"
#define TERMINAL_3270(obj) \
OBJECT_CHECK(Terminal3270, (obj), TYPE_TERMINAL_3270)
static int terminal_can_read(void *opaque)
{
Terminal3270 *t = opaque;
return INPUT_BUFFER_SIZE - t->in_len;
}
/*
* Protocol handshake done,
* signal guest by an unsolicited DE irq.
*/
static void TN3270_handshake_done(Terminal3270 *t)
{
CcwDevice *ccw_dev = CCW_DEVICE(t);
SubchDev *sch = ccw_dev->sch;
t->handshake_done = true;
sch->curr_status.scsw.dstat = SCSW_DSTAT_DEVICE_END;
css_conditional_io_interrupt(sch);
}
/*
* Receive inbound data from socket.
* For data given to guest, drop the data boundary IAC, IAC_EOR.
* TODO:
* Using "Reset" key on x3270 may result multiple commands in one packet.
* This usually happens when the user meets a poor traffic of the network.
* As of now, for such case, we simply terminate the connection,
* and we should come back here later with a better solution.
*/
static void terminal_read(void *opaque, const uint8_t *buf, int size)
{
Terminal3270 *t = opaque;
CcwDevice *ccw_dev = CCW_DEVICE(t);
SubchDev *sch = ccw_dev->sch;
int end;
assert(size <= (INPUT_BUFFER_SIZE - t->in_len));
memcpy(&t->inv[t->in_len], buf, size);
t->in_len += size;
if (t->in_len < 2) {
return;
}
if (!t->handshake_done) {
/*
* Receiving Terminal Type is the last step of handshake.
* The data format: IAC SB Terminal-Type IS <terminal type> IAC SE
* The code for Terminal-Type is 0x18, for IS is 0.
* Simply check the data format and mark handshake_done.
*/
if (t->in_len > 6 && t->inv[2] == 0x18 && t->inv[3] == 0x0 &&
t->inv[t->in_len - 2] == IAC && t->inv[t->in_len - 1] == IAC_SE) {
TN3270_handshake_done(t);
t->in_len = 0;
}
return;
}
for (end = 0; end < t->in_len - 1; end++) {
if (t->inv[end] == IAC && t->inv[end + 1] == IAC_EOR) {
break;
}
}
if (end == t->in_len - 2) {
/* Data is valid for consuming. */
t->in_len -= 2;
sch->curr_status.scsw.dstat = SCSW_DSTAT_ATTENTION;
css_conditional_io_interrupt(sch);
} else if (end < t->in_len - 2) {
/* "Reset" key is used. */
qemu_chr_fe_disconnect(&t->chr);
} else {
/* Gathering data. */
return;
}
}
static void terminal_init(EmulatedCcw3270Device *dev, Error **errp)
{
Terminal3270 *t = TERMINAL_3270(dev);
static bool terminal_available;
if (terminal_available) {
error_setg(errp, "Multiple 3270 terminals are not supported.");
return;
}
terminal_available = true;
qemu_chr_fe_set_handlers(&t->chr, terminal_can_read,
terminal_read, NULL, t, NULL, true);
}
static int read_payload_3270(EmulatedCcw3270Device *dev, uint32_t cda,
uint16_t count)
{
Terminal3270 *t = TERMINAL_3270(dev);
int len;
len = MIN(count, t->in_len);
cpu_physical_memory_write(cda, t->inv, len);
t->in_len -= len;
return len;
}
/* TN3270 uses binary transmission, which needs escape IAC to IAC IAC */
static int insert_IAC_escape_char(uint8_t *outv, int out_len)
{
int IAC_num = 0, new_out_len, i, j;
for (i = 0; i < out_len; i++) {
if (outv[i] == IAC) {
IAC_num++;
}
}
if (IAC_num == 0) {
return out_len;
}
new_out_len = out_len + IAC_num;
for (i = out_len - 1, j = new_out_len - 1; j > i && i >= 0; i--, j--) {
outv[j] = outv[i];
if (outv[i] == IAC) {
outv[--j] = IAC;
}
}
return new_out_len;
}
/*
* Write 3270 outbound to socket.
* Return the count of 3270 data field if succeeded, zero if failed.
*/
static int write_payload_3270(EmulatedCcw3270Device *dev, uint8_t cmd,
uint32_t cda, uint16_t count)
{
Terminal3270 *t = TERMINAL_3270(dev);
int retval = 0;
assert(count <= (OUTPUT_BUFFER_SIZE - 3) / 2);
if (!t->handshake_done) {
/*
* Before having finished 3270 negotiation,
* sending outbound data is prohibited.
*/
return 0;
}
if (!qemu_chr_fe_get_driver(&t->chr)) {
/* We just say we consumed all data if there's no backend. */
return count;
}
t->outv[0] = cmd;
cpu_physical_memory_read(cda, &t->outv[1], count);
t->out_len = count + 1;
t->out_len = insert_IAC_escape_char(t->outv, t->out_len);
t->outv[t->out_len++] = IAC;
t->outv[t->out_len++] = IAC_EOR;
retval = qemu_chr_fe_write_all(&t->chr, t->outv, t->out_len);
return (retval <= 0) ? 0 : (retval - 3);
}
static Property terminal_properties[] = {
DEFINE_PROP_CHR("chardev", Terminal3270, chr),
DEFINE_PROP_END_OF_LIST(),
};
static void terminal_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
EmulatedCcw3270Class *ck = EMULATED_CCW_3270_CLASS(klass);
dc->props = terminal_properties;
ck->init = terminal_init;
ck->read_payload_3270 = read_payload_3270;
ck->write_payload_3270 = write_payload_3270;
}
static const TypeInfo ccw_terminal_info = {
.name = TYPE_TERMINAL_3270,
.parent = TYPE_EMULATED_CCW_3270,
.instance_size = sizeof(Terminal3270),
.class_init = terminal_class_init,
.class_size = sizeof(EmulatedCcw3270Class),
};
static void register_types(void)
{
type_register_static(&ccw_terminal_info);
}
type_init(register_types)
|
