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
|
/* SPDX-License-Identifier: LGPL-2.1+ */
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "generator.h"
#include "log.h"
#include "mkdir.h"
#include "path-util.h"
#include "process-util.h"
#include "strv.h"
#include "terminal-util.h"
#include "unit-name.h"
#include "util.h"
#include "virt.h"
static const char *arg_dest = NULL;
static int add_symlink(const char *fservice, const char *tservice) {
char *from, *to;
int r;
assert(fservice);
assert(tservice);
from = strjoina(SYSTEM_DATA_UNIT_PATH "/", fservice);
to = strjoina(arg_dest, "/getty.target.wants/", tservice);
mkdir_parents_label(to, 0755);
r = symlink(from, to);
if (r < 0) {
/* In case console=hvc0 is passed this will very likely result in EEXIST */
if (errno == EEXIST)
return 0;
return log_error_errno(errno, "Failed to create symlink %s: %m", to);
}
return 0;
}
static int add_serial_getty(const char *tty) {
_cleanup_free_ char *n = NULL;
int r;
assert(tty);
log_debug("Automatically adding serial getty for /dev/%s.", tty);
r = unit_name_from_path_instance("serial-getty", tty, ".service", &n);
if (r < 0)
return log_error_errno(r, "Failed to generate service name: %m");
return add_symlink("serial-getty@.service", n);
}
static int add_container_getty(const char *tty) {
_cleanup_free_ char *n = NULL;
int r;
assert(tty);
log_debug("Automatically adding container getty for /dev/pts/%s.", tty);
r = unit_name_from_path_instance("container-getty", tty, ".service", &n);
if (r < 0)
return log_error_errno(r, "Failed to generate service name: %m");
return add_symlink("container-getty@.service", n);
}
static int verify_tty(const char *name) {
_cleanup_close_ int fd = -1;
const char *p;
/* Some TTYs are weird and have been enumerated but don't work
* when you try to use them, such as classic ttyS0 and
* friends. Let's check that and open the device and run
* isatty() on it. */
p = strjoina("/dev/", name);
/* O_NONBLOCK is essential here, to make sure we don't wait
* for DCD */
fd = open(p, O_RDWR|O_NONBLOCK|O_NOCTTY|O_CLOEXEC|O_NOFOLLOW);
if (fd < 0)
return -errno;
errno = 0;
if (isatty(fd) <= 0)
return errno > 0 ? -errno : -EIO;
return 0;
}
static int run(const char *dest, const char *dest_early, const char *dest_late) {
_cleanup_free_ char *active = NULL;
const char *j;
int r;
assert_se(arg_dest = dest);
if (detect_container() > 0) {
_cleanup_free_ char *container_ttys = NULL;
log_debug("Automatically adding console shell.");
r = add_symlink("console-getty.service", "console-getty.service");
if (r < 0)
return r;
/* When $container_ttys is set for PID 1, spawn
* gettys on all ptys named therein. Note that despite
* the variable name we only support ptys here. */
r = getenv_for_pid(1, "container_ttys", &container_ttys);
if (r > 0) {
const char *word, *state;
size_t l;
FOREACH_WORD(word, l, container_ttys, state) {
const char *t;
char tty[l + 1];
memcpy(tty, word, l);
tty[l] = 0;
/* First strip off /dev/ if it is specified */
t = path_startswith(tty, "/dev/");
if (!t)
t = tty;
/* Then, make sure it's actually a pty */
t = path_startswith(t, "pts/");
if (!t)
continue;
r = add_container_getty(t);
if (r < 0)
return r;
}
}
/* Don't add any further magic if we are in a container */
return 0;
}
if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
const char *word, *state;
size_t l;
/* Automatically add in a serial getty on all active
* kernel consoles */
FOREACH_WORD(word, l, active, state) {
_cleanup_free_ char *tty = NULL;
tty = strndup(word, l);
if (!tty)
return log_oom();
/* We assume that gettys on virtual terminals are
* started via manual configuration and do this magic
* only for non-VC terminals. */
if (isempty(tty) || tty_is_vc(tty))
continue;
if (verify_tty(tty) < 0)
continue;
r = add_serial_getty(tty);
if (r < 0)
return r;
}
}
/* Automatically add in a serial getty on the first
* virtualizer console */
FOREACH_STRING(j,
"hvc0",
"xvc0",
"hvsi0",
"sclp_line0",
"ttysclp0",
"3270!tty1") {
const char *p;
p = strjoina("/sys/class/tty/", j);
if (access(p, F_OK) < 0)
continue;
r = add_serial_getty(j);
if (r < 0)
return r;
}
return 0;
}
DEFINE_MAIN_GENERATOR_FUNCTION(run);
|