/* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009-2010 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
#define _BSD_SOURCE /* for daemon(3) */
+#ifdef HAVE_WINDOWS_H
+# include <windows.h>
+#endif
+
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <sys/select.h>
#include <sys/wait.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <errno.h>
#ifdef HAVE_PRINTF_H
-#include <printf.h>
+# include <printf.h>
#endif
+#include "sockets.h"
#include "c-ctype.h"
#include "ignore-value.h"
+#include "error.h"
#include "daemon.h"
static char *read_cmdline (void);
-/* Also in guestfs.c */
-#define GUESTFWD_ADDR "10.0.2.4"
-#define GUESTFWD_PORT "6666"
+#ifndef MAX
+# define MAX(a,b) ((a)>(b)?(a):(b))
+#endif
-/* This is only a hint. If not defined, ignore it. */
-#ifndef AI_ADDRCONFIG
-#define AI_ADDRCONFIG 0
+/* Not the end of the world if this open flag is not defined. */
+#ifndef O_CLOEXEC
+# define O_CLOEXEC 0
#endif
+/* If root device is an ext2 filesystem, this is the major and minor.
+ * This is so we can ignore this device from the point of view of the
+ * user, eg. in guestfs_list_devices and many other places.
+ */
+static dev_t root_device = 0;
+
int verbose = 0;
static int print_shell_quote (FILE *stream, const struct printf_info *info, const void *const *args);
#endif
#endif
+#ifdef WIN32
+static int
+daemon (int nochdir, int noclose)
+{
+ fprintf (stderr,
+ "On Windows the daemon does not support forking into the "
+ "background.\nYou *must* run the daemon with the -f option.\n");
+ exit (EXIT_FAILURE);
+}
+#endif /* WIN32 */
+
+#ifdef WIN32
+static int
+winsock_init (void)
+{
+ int r;
+
+ /* http://msdn2.microsoft.com/en-us/library/ms742213.aspx */
+ r = gl_sockets_startup (SOCKETS_2_2);
+ return r == 0 ? 0 : -1;
+}
+#else /* !WIN32 */
+static int
+winsock_init (void)
+{
+ return 0;
+}
+#endif /* !WIN32 */
+
/* Location to mount root device. */
const char *sysroot = "/sysroot"; /* No trailing slash. */
int sysroot_len = 8;
+/* Not used explicitly, but required by the gnulib 'error' module. */
+const char *program_name = "guestfsd";
+
static void
usage (void)
{
fprintf (stderr,
- "guestfsd [-f|--foreground] [-c|--channel vmchannel] [-v|--verbose]\n");
+ "guestfsd [-f|--foreground] [-v|--verbose]\n");
}
int
main (int argc, char *argv[])
{
- static const char *options = "fc:v?";
+ static const char *options = "fv?";
static const struct option long_options[] = {
- { "channel", required_argument, 0, 'c' },
{ "foreground", 0, 0, 'f' },
{ "help", 0, 0, '?' },
{ "verbose", 0, 0, 'v' },
int c;
int dont_fork = 0;
char *cmdline;
- char *vmchannel = NULL;
+
+ ignore_value (chdir ("/"));
+
+ if (winsock_init () == -1)
+ error (EXIT_FAILURE, 0, "winsock initialization failed");
#ifdef HAVE_REGISTER_PRINTF_SPECIFIER
/* http://udrepper.livejournal.com/20948.html */
#endif
#endif
+ struct stat statbuf;
+ if (stat ("/", &statbuf) == 0)
+ root_device = statbuf.st_dev;
+
for (;;) {
c = getopt_long (argc, argv, options, long_options, NULL);
if (c == -1) break;
switch (c) {
- case 'c':
- vmchannel = optarg;
- break;
-
case 'f':
dont_fork = 1;
break;
perror ("sigaction SIGPIPE"); /* but try to continue anyway ... */
#endif
+#ifdef WIN32
+# define setenv(n,v,f) _putenv(n "=" v)
+#endif
/* Set up a basic environment. After we are called by /init the
* environment is essentially empty.
* https://bugzilla.redhat.com/show_bug.cgi?id=502074#c5
+ *
+ * NOTE: if you change $PATH, you must also change 'prog_exists'
+ * function below.
*/
- setenv ("PATH", "/usr/bin:/bin", 1);
+ setenv ("PATH", "/sbin:/usr/sbin:/bin:/usr/bin", 1);
setenv ("SHELL", "/bin/sh", 1);
setenv ("LC_ALL", "C", 1);
+ setenv ("TERM", "dumb", 1);
+#ifndef WIN32
/* We document that umask defaults to 022 (it should be this anyway). */
umask (022);
-
- /* Get the vmchannel string.
- *
- * Sources:
- * --channel/-c option on the command line
- * guestfs_vmchannel=... from the kernel command line
- * guestfs=... from the kernel command line
- * built-in default
- *
- * At the moment we expect this to contain "tcp:ip:port" but in
- * future it might contain a device name, eg. "/dev/vcon4" for
- * virtio-console vmchannel.
+#else
+ /* This is the default for Windows anyway. It's not even clear if
+ * Windows ever uses this -- the MSDN documentation for the function
+ * contains obvious errors.
*/
- if (vmchannel == NULL && cmdline) {
- char *p;
- size_t len;
-
- p = strstr (cmdline, "guestfs_vmchannel=");
- if (p) {
- len = strcspn (p + 18, " \t\n");
- vmchannel = strndup (p + 18, len);
- if (!vmchannel) {
- perror ("strndup");
- exit (EXIT_FAILURE);
- }
- }
-
- /* Old libraries passed guestfs=host:port. Rewrite it as tcp:host:port. */
- if (vmchannel == NULL) {
- /* We will rewrite it part of the "guestfs=" string with
- * "tcp:" hence p + 4 below. */
- p = strstr (cmdline, "guestfs=");
- if (p) {
- len = strcspn (p + 4, " \t\n");
- vmchannel = strndup (p + 4, len);
- if (!vmchannel) {
- perror ("strndup");
- exit (EXIT_FAILURE);
- }
- memcpy (vmchannel, "tcp:", 4);
- }
- }
- }
-
- /* Default vmchannel. */
- if (vmchannel == NULL) {
- vmchannel = strdup ("tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT);
- if (!vmchannel) {
- perror ("strdup");
- exit (EXIT_FAILURE);
- }
- }
-
- if (verbose)
- printf ("vmchannel: %s\n", vmchannel);
-
- /* Connect to vmchannel. */
- int sock = -1;
-
- if (STREQLEN (vmchannel, "tcp:", 4)) {
- /* Resolve the hostname. */
- struct addrinfo *res, *rr;
- struct addrinfo hints;
- int r;
- char *host, *port;
-
- host = vmchannel+4;
- port = strchr (host, ':');
- if (port) {
- port[0] = '\0';
- port++;
- } else {
- fprintf (stderr, "vmchannel: expecting \"tcp:<ip>:<port>\": %s\n",
- vmchannel);
- exit (EXIT_FAILURE);
- }
-
- memset (&hints, 0, sizeof hints);
- hints.ai_socktype = SOCK_STREAM;
- hints.ai_flags = AI_ADDRCONFIG;
- r = getaddrinfo (host, port, &hints, &res);
- if (r != 0) {
- fprintf (stderr, "%s:%s: %s\n",
- host, port, gai_strerror (r));
- exit (EXIT_FAILURE);
- }
-
- /* Connect to the given TCP socket. */
- for (rr = res; rr != NULL; rr = rr->ai_next) {
- sock = socket (rr->ai_family, rr->ai_socktype, rr->ai_protocol);
- if (sock != -1) {
- if (connect (sock, rr->ai_addr, rr->ai_addrlen) == 0)
- break;
- perror ("connect");
-
- close (sock);
- sock = -1;
- }
- }
- freeaddrinfo (res);
- } else {
- fprintf (stderr,
- "unknown vmchannel connection type: %s\n"
- "expecting \"tcp:<ip>:<port>\"\n",
- vmchannel);
- exit (EXIT_FAILURE);
- }
+ _umask (0);
+#endif
+ /* Connect to virtio-serial channel. */
+ int sock = open ("/dev/virtio-ports/org.libguestfs.channel.0",
+ O_RDWR | O_CLOEXEC);
if (sock == -1) {
fprintf (stderr,
"\n"
- "Failed to connect to any vmchannel implementation.\n"
- "vmchannel: %s\n"
+ "Failed to connect to virtio-serial channel.\n"
"\n"
"This is a fatal error and the appliance will now exit.\n"
"\n"
"'libguestfs-test-tool' and provide the complete, unedited\n"
"output to the libguestfs developers, either in a bug report\n"
"or on the libguestfs redhat com mailing list.\n"
- "\n",
- vmchannel);
+ "\n");
+ perror ("/dev/virtio-ports/org.libguestfs.channel.0");
exit (EXIT_FAILURE);
}
xdrmem_create (&xdr, lenbuf, sizeof lenbuf, XDR_ENCODE);
xdr_u_int (&xdr, &len);
- if (xwrite (sock, lenbuf, sizeof lenbuf) == -1)
+ if (xwrite (sock, lenbuf, sizeof lenbuf) == -1) {
+ perror ("xwrite");
exit (EXIT_FAILURE);
+ }
xdr_destroy (&xdr);
return r;
}
+/* Return true iff device is the root device (and therefore should be
+ * ignored from the point of view of user calls).
+ */
+int
+is_root_device (const char *device)
+{
+ struct stat statbuf;
+ if (stat (device, &statbuf) == -1) {
+ perror (device);
+ return 0;
+ }
+ if (statbuf.st_rdev == root_device)
+ return 1;
+ return 0;
+}
+
/* Turn "/path" into "/sysroot/path".
*
* Caller must check for NULL and call reply_with_perror ("malloc")
if (new_str == NULL) {
reply_with_perror ("strdup");
free_strings (*argv);
+ return -1;
}
} else
new_str = NULL;
return 0;
}
-int
+size_t
count_strings (char *const *argv)
{
- int argc;
+ size_t argc;
for (argc = 0; argv[argc] != NULL; ++argc)
;
return argc;
}
+/* http://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2 */
+int
+is_power_of_2 (unsigned long v)
+{
+ return v && ((v & (v - 1)) == 0);
+}
+
static int
compare (const void *vp1, const void *vp2)
{
* error messages in the *stderror buffer. If using this flag,
* you should pass stdoutput as NULL because nothing could ever be
* captured in that buffer.
+ *
+ * COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN: For running external
+ * commands on chrooted files correctly (see RHBZ#579608) specifying
+ * this flag causes another process to be forked which chroots into
+ * sysroot and just copies the input file to stdin of the specified
+ * command. The file descriptor is ORed with the flags, and that file
+ * descriptor is always closed by this function. See hexdump.c for an
+ * example of usage.
*/
int
commandrvf (char **stdoutput, char **stderror, int flags,
{
int so_size = 0, se_size = 0;
int so_fd[2], se_fd[2];
- pid_t pid;
+ int flag_copy_stdin = flags & COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN;
+ int stdin_fd[2] = { -1, -1 };
+ pid_t pid, stdin_pid = -1;
int r, quit, i;
fd_set rset, rset2;
char buf[256];
printf ("\n");
}
+ /* Note: abort is used in a few places along the error paths early
+ * in this function. This is because (a) cleaning up correctly is
+ * very complex at these places and (b) abort is used when a
+ * resource problems is indicated which would be due to much more
+ * serious issues - eg. memory or file descriptor leaks. We
+ * wouldn't expect fork(2) or pipe(2) to fail in normal
+ * circumstances.
+ */
+
if (pipe (so_fd) == -1 || pipe (se_fd) == -1) {
- perror ("pipe");
- return -1;
+ error (0, errno, "pipe");
+ abort ();
+ }
+
+ if (flag_copy_stdin) {
+ if (pipe (stdin_fd) == -1) {
+ error (0, errno, "pipe");
+ abort ();
+ }
}
pid = fork ();
if (pid == -1) {
- perror ("fork");
- close (so_fd[0]);
- close (so_fd[1]);
- close (se_fd[0]);
- close (se_fd[1]);
- return -1;
+ error (0, errno, "fork");
+ abort ();
}
- if (pid == 0) { /* Child process. */
+ if (pid == 0) { /* Child process running the command. */
+ signal (SIGPIPE, SIG_DFL);
close (0);
- open ("/dev/null", O_RDONLY); /* Set stdin to /dev/null (ignore failure) */
+ if (flag_copy_stdin) {
+ dup2 (stdin_fd[0], 0);
+ close (stdin_fd[0]);
+ close (stdin_fd[1]);
+ } else {
+ /* Set stdin to /dev/null (ignore failure) */
+ ignore_value (open ("/dev/null", O_RDONLY));
+ }
close (so_fd[0]);
close (se_fd[0]);
if (!(flags & COMMAND_FLAG_FOLD_STDOUT_ON_STDERR))
execvp (argv[0], (void *) argv);
perror (argv[0]);
- _exit (1);
+ _exit (EXIT_FAILURE);
+ }
+
+ if (flag_copy_stdin) {
+ int fd = flags & COMMAND_FLAG_FD_MASK;
+
+ stdin_pid = fork ();
+ if (stdin_pid == -1) {
+ error (0, errno, "fork");
+ abort ();
+ }
+
+ if (stdin_pid == 0) { /* Child process copying stdin. */
+ close (so_fd[0]);
+ close (so_fd[1]);
+ close (se_fd[0]);
+ close (se_fd[1]);
+
+ close (1);
+ dup2 (stdin_fd[1], 1);
+ close (stdin_fd[0]);
+ close (stdin_fd[1]);
+
+ if (chroot (sysroot) == -1) {
+ perror ("chroot");
+ _exit (EXIT_FAILURE);
+ }
+
+ ssize_t n;
+ char buffer[BUFSIZ];
+ while ((n = read (fd, buffer, sizeof buffer)) > 0) {
+ if (xwrite (1, buffer, n) == -1)
+ /* EPIPE error indicates the command process has exited
+ * early. If the command process fails that will be caught
+ * by the daemon, and if not, then it's not an error.
+ */
+ _exit (errno == EPIPE ? EXIT_SUCCESS : EXIT_FAILURE);
+ }
+
+ if (n == -1) {
+ perror ("read");
+ _exit (EXIT_FAILURE);
+ }
+
+ if (close (fd) == -1) {
+ perror ("close");
+ _exit (EXIT_FAILURE);
+ }
+
+ _exit (EXIT_SUCCESS);
+ }
+
+ close (fd);
+ close (stdin_fd[0]);
+ close (stdin_fd[1]);
}
/* Parent process. */
quit = 0;
while (quit < 2) {
+ again:
rset2 = rset;
r = select (MAX (so_fd[0], se_fd[0]) + 1, &rset2, NULL, NULL, NULL);
if (r == -1) {
+ if (errno == EINTR)
+ goto again;
+
perror ("select");
quit:
- if (stdoutput) free (*stdoutput);
- if (stderror) free (*stderror);
+ if (stdoutput) {
+ free (*stdoutput);
+ *stdoutput = NULL;
+ }
+ if (stderror) {
+ free (*stderror);
+ /* Need to return non-NULL *stderror here since most callers
+ * will try to print and then free the err string.
+ * Unfortunately recovery from strdup failure here is not
+ * possible.
+ */
+ *stderror = strdup ("error running external command, "
+ "see debug output for details");
+ }
close (so_fd[0]);
close (se_fd[0]);
waitpid (pid, NULL, 0);
+ if (stdin_pid >= 0) waitpid (stdin_pid, NULL, 0);
return -1;
}
}
}
+ if (flag_copy_stdin) {
+ /* Check copy process didn't fail. */
+ if (waitpid (stdin_pid, &r, 0) != stdin_pid) {
+ perror ("waitpid");
+ kill (pid, 9);
+ waitpid (pid, NULL, 0);
+ return -1;
+ }
+
+ if (!WIFEXITED (r) || WEXITSTATUS (r) != 0) {
+ fprintf (stderr, "failed copying from input file, see earlier messages\n");
+ kill (pid, 9);
+ waitpid (pid, NULL, 0);
+ return -1;
+ }
+ }
+
/* Get the exit status of the command. */
if (waitpid (pid, &r, 0) != pid) {
perror ("waitpid");
return lines;
}
+/* Skip leading and trailing whitespace, updating the original string
+ * in-place.
+ */
+void
+trim (char *str)
+{
+ size_t len = strlen (str);
+
+ while (len > 0 && c_isspace (str[len-1])) {
+ str[len-1] = '\0';
+ len--;
+ }
+
+ const char *p = str;
+ while (*p && c_isspace (*p)) {
+ p++;
+ len--;
+ }
+
+ memmove (str, p, len+1);
+}
+
/* printf helper function so we can use %Q ("quoted") and %R to print
- * shell-quoted strings. See HACKING file for more details.
+ * shell-quoted strings. See guestfs(3)/EXTENDING LIBGUESTFS for more
+ * details.
*/
static int
print_shell_quote (FILE *stream,
* the device nodes themselves will exist in the appliance.
*/
int
-device_name_translation (char *device, const char *func)
+device_name_translation (char *device)
{
int fd;
fd = open (device, O_RDONLY);
if (fd >= 0) {
+ close_ok:
close (fd);
return 0;
}
- if (errno != ENXIO && errno != ENOENT) {
- error:
- reply_with_perror ("%s: %s", func, device);
+ if (errno != ENXIO && errno != ENOENT)
return -1;
- }
/* If the name begins with "/dev/sd" then try the alternatives. */
if (STRNEQLEN (device, "/dev/sd", 7))
- goto error;
+ return -1;
device[5] = 'h'; /* /dev/hd (old IDE driver) */
fd = open (device, O_RDONLY);
- if (fd >= 0) {
- close (fd);
- return 0;
- }
+ if (fd >= 0)
+ goto close_ok;
device[5] = 'v'; /* /dev/vd (for virtio devices) */
fd = open (device, O_RDONLY);
- if (fd >= 0) {
- close (fd);
- return 0;
- }
+ if (fd >= 0)
+ goto close_ok;
device[5] = 's'; /* Restore original device name. */
- goto error;
+ return -1;
+}
+
+/* Check program exists and is executable on $PATH. Actually, we
+ * just assume PATH contains the default entries (see main() above).
+ */
+int
+prog_exists (const char *prog)
+{
+ static const char * const dirs[] =
+ { "/sbin", "/usr/sbin", "/bin", "/usr/bin" };
+ size_t i;
+ char buf[1024];
+
+ for (i = 0; i < sizeof dirs / sizeof dirs[0]; ++i) {
+ snprintf (buf, sizeof buf, "%s/%s", dirs[i], prog);
+ if (access (buf, X_OK) == 0)
+ return 1;
+ }
+ return 0;
}
/* LVM and other commands aren't synchronous, especially when udev is
* involved. eg. You can create or remove some device, but the /dev
* device node won't appear until some time later. This means that
* you get an error if you run one command followed by another.
+ *
* Use 'udevadm settle' after certain commands, but don't be too
* fussed if it fails.
+ *
+ * 'udevsettle' was the old name for this command (RHEL 5). This was
+ * deprecated in favour of 'udevadm settle'. The old 'udevsettle'
+ * command was left as a symlink. Then in Fedora 13 the old symlink
+ * remained but it stopped working (RHBZ#548121), so we have to be
+ * careful not to assume that we can use 'udevsettle' if it exists.
*/
void
udev_settle (void)
{
- static int which_prog = 0;
-
- if (which_prog == 0) {
- if (access ("/sbin/udevsettle", X_OK) == 0)
- which_prog = 2;
- else if (access ("/sbin/udevadm", X_OK) == 0)
- which_prog = 1;
- else
- which_prog = 3;
- }
-
- switch (which_prog) {
- case 1:
- command (NULL, NULL, "/sbin/udevadm", "settle", NULL);
- break;
- case 2:
- command (NULL, NULL, "/sbin/udevsettle", NULL);
- break;
- default:
- ;
- }
+ (void) command (NULL, NULL, "udevadm", "settle", NULL);
+ (void) command (NULL, NULL, "udevsettle", NULL);
}