1 /* libguestfs - the guestfsd daemon
2 * Copyright (C) 2009 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <sys/types.h>
29 #include <sys/resource.h>
31 #include "../src/guestfs_protocol.h"
35 /* This command exposes debugging information, internals and
36 * status. There is no comprehensive documentation for this
37 * command. You have to look at the source code in this file
38 * to find out what you can do.
40 * Commands always output a freeform string.
42 * Since libguestfs 1.5.7, the debug command has been enabled
43 * by default for all builds (previously you had to enable it
44 * in configure). This command is not part of the stable ABI
45 * and may change at any time.
50 char * (*f) (const char *subcmd, int argc, char *const *const argv);
53 static char *debug_help (const char *subcmd, int argc, char *const *const argv);
54 static char *debug_core_pattern (const char *subcmd, int argc, char *const *const argv);
55 static char *debug_env (const char *subcmd, int argc, char *const *const argv);
56 static char *debug_fds (const char *subcmd, int argc, char *const *const argv);
57 static char *debug_ls (const char *subcmd, int argc, char *const *const argv);
58 static char *debug_ll (const char *subcmd, int argc, char *const *const argv);
59 static char *debug_progress (const char *subcmd, int argc, char *const *const argv);
60 static char *debug_segv (const char *subcmd, int argc, char *const *const argv);
61 static char *debug_sh (const char *subcmd, int argc, char *const *const argv);
63 static struct cmd cmds[] = {
64 { "help", debug_help },
65 { "core_pattern", debug_core_pattern },
70 { "progress", debug_progress },
71 { "segv", debug_segv },
77 do_debug (const char *subcmd, char *const *argv)
81 for (i = argc = 0; argv[i] != NULL; ++i)
84 for (i = 0; cmds[i].cmd != NULL; ++i) {
85 if (STRCASEEQ (subcmd, cmds[i].cmd))
86 return cmds[i].f (subcmd, argc, argv);
89 reply_with_error ("use 'debug help' to list the supported commands");
94 debug_help (const char *subcmd, int argc, char *const *const argv)
99 r = strdup ("Commands supported:");
101 reply_with_perror ("strdup");
106 for (i = 0; cmds[i].cmd != NULL; ++i) {
107 len += strlen (cmds[i].cmd) + 1; /* space + new command */
108 p = realloc (r, len + 1); /* +1 for the final NUL */
110 reply_with_perror ("realloc");
117 strcat (r, cmds[i].cmd);
125 debug_fds (const char *subcmd, int argc, char *const *const argv)
133 char fname[256], link[256];
136 fp = open_memstream (&out, &size);
138 reply_with_perror ("open_memstream");
142 dir = opendir ("/proc/self/fd");
144 reply_with_perror ("opendir: /proc/self/fd");
149 while ((d = readdir (dir)) != NULL) {
150 if (STREQ (d->d_name, ".") || STREQ (d->d_name, ".."))
153 snprintf (fname, sizeof fname, "/proc/self/fd/%s", d->d_name);
155 r = lstat (fname, &statbuf);
157 reply_with_perror ("stat: %s", fname);
164 if (S_ISLNK (statbuf.st_mode)) {
165 r = readlink (fname, link, sizeof link - 1);
167 reply_with_perror ("readline: %s", fname);
175 fprintf (fp, "%2s %s\n", d->d_name, link);
177 fprintf (fp, "%2s 0%o\n", d->d_name, statbuf.st_mode);
182 if (closedir (dir) == -1) {
183 reply_with_perror ("closedir");
191 /* Force a segfault in the daemon. */
193 debug_segv (const char *subcmd, int argc, char *const *const argv)
199 /* Run an arbitrary shell command using /bin/sh from the appliance.
201 * Note this is somewhat different from the ordinary guestfs_sh command
202 * because it's not using the guest shell, and is not chrooted.
205 debug_sh (const char *subcmd, int argc, char *const *const argv)
208 reply_with_error ("sh: expecting a command to run");
215 /* guestfish splits the parameter(s) into a list of strings,
216 * and we have to reassemble them here. Not ideal. XXX
218 for (i = len = 0; i < argc; ++i)
219 len += strlen (argv[i]) + 1;
222 reply_with_perror ("malloc");
225 for (i = j = 0; i < argc; ++i) {
226 len = strlen (argv[i]);
227 memcpy (&cmd[j], argv[i], len);
234 /* Set up some environment variables. */
235 setenv ("root", sysroot, 1);
236 if (access ("/sys/block/sda", F_OK) == 0)
237 setenv ("sd", "sd", 1);
238 else if (access ("/sys/block/hda", F_OK) == 0)
239 setenv ("sd", "hd", 1);
240 else if (access ("/sys/block/vda", F_OK) == 0)
241 setenv ("sd", "vd", 1);
244 int r = commandf (NULL, &err, COMMAND_FLAG_FOLD_STDOUT_ON_STDERR,
245 "/bin/sh", "-c", cmd, NULL);
249 reply_with_error ("%s", err);
257 /* Print the environment that commands get (by running external printenv). */
259 debug_env (const char *subcmd, int argc, char *const *const argv)
264 r = command (&out, &err, "printenv", NULL);
266 reply_with_error ("printenv: %s", err);
277 /* List files in the appliance. */
279 debug_ls (const char *subcmd, int argc, char *const *const argv)
281 int len = count_strings (argv);
282 const char *cargv[len+3];
287 for (i = 0; i < len; ++i)
288 cargv[2+i] = argv[i];
294 r = commandv (&out, &err, (void *) cargv);
296 reply_with_error ("ls: %s", err);
307 /* List files in the appliance. */
309 debug_ll (const char *subcmd, int argc, char *const *const argv)
311 int len = count_strings (argv);
312 const char *cargv[len+3];
317 for (i = 0; i < len; ++i)
318 cargv[2+i] = argv[i];
324 r = commandv (&out, &err, (void *) cargv);
326 reply_with_error ("ll: %s", err);
337 /* Generate progress notification messages in order to test progress bars. */
339 debug_progress (const char *subcmd, int argc, char *const *const argv)
343 reply_with_error ("progress: expecting arg (time in seconds as string)");
347 char *secs_str = argv[0];
349 if (sscanf (secs_str, "%u", &secs) != 1 || secs == 0)
353 unsigned tsecs = secs * 10; /* 1/10ths of seconds */
354 for (i = 1; i <= tsecs; ++i) {
356 notify_progress ((uint64_t) i, (uint64_t) tsecs);
359 char *ret = strdup ("ok");
361 reply_with_perror ("strdup");
368 /* Enable core dumping to the given core pattern.
369 * Note that this pattern is relative to any chroot of the process which
370 * crashes. This means that if you want to write the core file to the guest's
371 * storage the pattern must start with /sysroot only if the command which
372 * crashes doesn't chroot.
375 debug_core_pattern (const char *subcmd, int argc, char *const *const argv)
378 reply_with_error ("core_pattern: expecting a core pattern");
382 const char *pattern = argv[0];
383 const size_t pattern_len = strlen(pattern);
385 #define CORE_PATTERN "/proc/sys/kernel/core_pattern"
386 int fd = open (CORE_PATTERN, O_WRONLY);
388 reply_with_perror ("open: " CORE_PATTERN);
391 if (write (fd, pattern, pattern_len) < (ssize_t) pattern_len) {
392 reply_with_perror ("write: " CORE_PATTERN);
395 if (close (fd) == -1) {
396 reply_with_perror ("close: " CORE_PATTERN);
400 struct rlimit limit = {
401 .rlim_cur = RLIM_INFINITY,
402 .rlim_max = RLIM_INFINITY
404 if (setrlimit (RLIMIT_CORE, &limit) == -1) {
405 reply_with_perror ("setrlimit (RLIMIT_CORE)");
409 char *ret = strdup ("ok");
411 reply_with_perror ("strdup");
419 write_cb (void *fd_ptr, const void *buf, size_t len)
421 int fd = *(int *)fd_ptr;
422 return xwrite (fd, buf, len);
425 /* Has one FileIn parameter. */
427 do_debug_upload (const char *filename, int mode)
429 /* Not chrooted - this command lets you upload a file to anywhere
432 int fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, mode);
438 reply_with_perror ("%s", filename);
442 int r = receive_file (write_cb, &fd);
443 if (r == -1) { /* write error */
447 reply_with_error ("write error: %s", filename);
451 if (r == -2) { /* cancellation from library */
453 /* Do NOT send any error. */
457 if (close (fd) == -1) {
459 if (r == -1) /* if r == 0, file transfer ended already */
462 reply_with_perror ("close: %s", filename);