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
|
/* libguestfs - the guestfsd daemon
* Copyright (C) 2009 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dirent.h>
#include "../src/guestfs_protocol.h"
#include "daemon.h"
#include "actions.h"
/* This command exposes debugging information, internals and
* status. There is no comprehensive documentation for this
* command. You have to look at the source code in this file
* to find out what you can do.
*
* Commands always output a freeform string.
*/
#if ENABLE_DEBUG_COMMAND
struct cmd {
const char *cmd;
char * (*f) (const char *subcmd, int argc, char *const *const argv);
};
static char *debug_help (const char *subcmd, int argc, char *const *const argv);
static char *debug_fds (const char *subcmd, int argc, char *const *const argv);
static char *debug_segv (const char *subcmd, int argc, char *const *const argv);
static char *debug_sh (const char *subcmd, int argc, char *const *const argv);
static struct cmd cmds[] = {
{ "help", debug_help },
{ "fds", debug_fds },
{ "segv", debug_segv },
{ "sh", debug_sh },
{ NULL, NULL }
};
#endif
char *
do_debug (const char *subcmd, char *const *const argv)
{
#if ENABLE_DEBUG_COMMAND
int argc, i;
for (i = argc = 0; argv[i] != NULL; ++i)
argc++;
for (i = 0; cmds[i].cmd != NULL; ++i) {
if (strcasecmp (subcmd, cmds[i].cmd) == 0)
return cmds[i].f (subcmd, argc, argv);
}
reply_with_error ("use 'debug help' to list the supported commands");
return NULL;
#else
reply_with_error ("guestfsd was not configured with --enable-debug-command");
return NULL;
#endif
}
#if ENABLE_DEBUG_COMMAND
static char *
debug_help (const char *subcmd, int argc, char *const *const argv)
{
int len, i;
char *r, *p;
r = strdup ("Commands supported:");
if (!r) {
reply_with_perror ("strdup");
return NULL;
}
len = strlen (r);
for (i = 0; cmds[i].cmd != NULL; ++i) {
len += strlen (cmds[i].cmd) + 1; /* space + new command */
p = realloc (r, len + 1); /* +1 for the final NUL */
if (p == NULL) {
reply_with_perror ("realloc");
free (r);
return NULL;
}
r = p;
strcat (r, " ");
strcat (r, cmds[i].cmd);
}
return r;
}
/* Show open FDs. */
static char *
debug_fds (const char *subcmd, int argc, char *const *const argv)
{
int r;
char *out;
size_t size;
FILE *fp;
DIR *dir;
struct dirent *d;
char fname[256], link[256];
struct stat statbuf;
fp = open_memstream (&out, &size);
if (!fp) {
reply_with_perror ("open_memstream");
return NULL;
}
dir = opendir ("/proc/self/fd");
if (!dir) {
reply_with_perror ("opendir: /proc/self/fd");
fclose (fp);
return NULL;
}
while ((d = readdir (dir)) != NULL) {
if (strcmp (d->d_name, ".") == 0 || strcmp (d->d_name, "..") == 0)
continue;
snprintf (fname, sizeof fname, "/proc/self/fd/%s", d->d_name);
r = lstat (fname, &statbuf);
if (r == -1) {
reply_with_perror ("stat: %s", fname);
fclose (fp);
free (out);
closedir (dir);
return NULL;
}
if (S_ISLNK (statbuf.st_mode)) {
r = readlink (fname, link, sizeof link - 1);
if (r == -1) {
reply_with_perror ("readline: %s", fname);
fclose (fp);
free (out);
closedir (dir);
return NULL;
}
link[r] = '\0';
fprintf (fp, "%2s %s\n", d->d_name, link);
} else
fprintf (fp, "%2s 0%o\n", d->d_name, statbuf.st_mode);
}
fclose (fp);
if (closedir (dir) == -1) {
reply_with_perror ("closedir");
free (out);
return NULL;
}
return out;
}
/* Force a segfault in the daemon. */
static char *
debug_segv (const char *subcmd, int argc, char *const *const argv)
{
*(int*)0 = 0;
return NULL;
}
/* Run an arbitrary shell command. */
static char *
debug_sh (const char *subcmd, int argc, char *const *const argv)
{
int r;
char *out, *err;
r = commandv (&out, &err, argv);
if (r == -1) {
reply_with_error ("ps: %s", err);
free (out);
free (err);
return NULL;
}
free (err);
return out;
}
#endif /* ENABLE_DEBUG_COMMAND */
|
