#include <config.h>
+#include <errno.h>
+#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <time.h>
#include <sys/stat.h>
#include <sys/select.h>
+#include <sys/wait.h>
#include <utime.h>
#ifdef HAVE_SYS_TYPES_H
#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
-static const char *kernel_name = "vmlinuz." REPO "." host_cpu;
-static const char *initrd_name = "initramfs." REPO "." host_cpu ".img";
+static const char *kernel_name = "vmlinuz." host_cpu;
+static const char *initrd_name = "initramfs." host_cpu ".img";
static int find_path (guestfs_h *g, int (*pred) (guestfs_h *g, const char *pelem, void *data), void *data, char **pelem);
static int dir_contains_file (const char *dir, const char *file);
static char *calculate_supermin_checksum (guestfs_h *g, const char *supermin_path);
static int check_for_cached_appliance (guestfs_h *g, const char *supermin_path, const char *checksum, char **kernel, char **initrd, char **appliance);
static int build_supermin_appliance (guestfs_h *g, const char *supermin_path, const char *checksum, char **kernel, char **initrd, char **appliance);
+static int run_supermin_helper (guestfs_h *g, const char *supermin_path, const char *cachedir, size_t cdlen);
/* Locate or build the appliance.
*
{
size_t len = 2 * strlen (supermin_path) + 256;
char cmd[len];
- snprintf (cmd, len,
- "febootstrap-supermin-helper%s "
- "-f checksum "
- "-k '%s/kmod.whitelist' "
- "'%s/supermin.d' "
- host_cpu,
- g->verbose ? " --verbose" : "",
- supermin_path,
- supermin_path);
+ int pass_u_g_args = getuid () != geteuid () || getgid () != getegid ();
+
+ if (!pass_u_g_args)
+ snprintf (cmd, len,
+ "febootstrap-supermin-helper%s "
+ "-f checksum "
+ "'%s/supermin.d' "
+ host_cpu,
+ g->verbose ? " --verbose" : "",
+ supermin_path);
+ else
+ snprintf (cmd, len,
+ "febootstrap-supermin-helper%s "
+ "-u %i "
+ "-g %i "
+ "-f checksum "
+ "'%s/supermin.d' "
+ host_cpu,
+ g->verbose ? " --verbose" : "",
+ geteuid (), getegid (),
+ supermin_path);
if (g->verbose)
guestfs___print_timestamped_message (g, "%s", cmd);
const char *supermin_path, const char *checksum,
char **kernel, char **initrd, char **appliance)
{
- const char *tmpdir = guestfs___tmpdir ();
+ const char *tmpdir = guestfs_tmpdir ();
- size_t len = strlen (tmpdir) + strlen (checksum) + 2;
+ size_t len = strlen (tmpdir) + strlen (checksum) + 10;
char cachedir[len];
- snprintf (cachedir, len, "%s/%s", tmpdir, checksum);
+ snprintf (cachedir, len, "%s/guestfs.%s", tmpdir, checksum);
/* Touch the directory to prevent it being deleting in a rare race
* between us doing the checks and a tmp cleaner running. Note this
if (g->verbose)
guestfs___print_timestamped_message (g, "begin building supermin appliance");
- const char *tmpdir = guestfs___tmpdir ();
- size_t cdlen = strlen (tmpdir) + strlen (checksum) + 2;
- char cachedir[cdlen];
- snprintf (cachedir, cdlen, "%s/%s", tmpdir, checksum);
+ const char *tmpdir = guestfs_tmpdir ();
- /* Don't worry about this failing, because the command below will
- * fail if the directory doesn't exist. Note the directory might
- * already exist, eg. if a tmp cleaner has removed the existing
- * appliance but not the directory itself.
- */
- (void) mkdir (cachedir, 0755);
+ size_t tmpcdlen = strlen (tmpdir) + 16;
+ char tmpcd[tmpcdlen];
+ snprintf (tmpcd, tmpcdlen, "%s/guestfs.XXXXXX", tmpdir);
- /* Set a sensible umask in the subprocess, so kernel and initrd
- * output files are world-readable (RHBZ#610880).
- */
- size_t cmdlen = 2 * strlen (supermin_path) + 3 * (cdlen + 16) + 256;
- char cmd[cmdlen];
- snprintf (cmd, cmdlen,
- "umask 0022; "
- "febootstrap-supermin-helper%s "
- "-f ext2 "
- "-k '%s/kmod.whitelist' "
- "'%s/supermin.d' "
- host_cpu " "
- "%s/kernel %s/initrd %s/root",
- g->verbose ? " --verbose" : "",
- supermin_path, supermin_path,
- cachedir, cachedir, cachedir);
- if (g->verbose)
- guestfs___print_timestamped_message (g, "%s", cmd);
- int r = system (cmd);
- if (r == -1 || WEXITSTATUS (r) != 0) {
- error (g, _("external command failed: %s"), cmd);
+ if (NULL == mkdtemp (tmpcd)) {
+ error (g, _("failed to create temporary cache directory: %m"));
return -1;
}
if (g->verbose)
+ guestfs___print_timestamped_message (g, "run febootstrap-supermin-helper");
+
+ int r = run_supermin_helper (g, supermin_path, tmpcd, tmpcdlen);
+ if (r == -1)
+ return -1;
+
+ if (g->verbose)
guestfs___print_timestamped_message (g, "finished building supermin appliance");
+ size_t cdlen = strlen (tmpdir) + strlen (checksum) + 10;
+ char cachedir[cdlen];
+ snprintf (cachedir, cdlen, "%s/guestfs.%s", tmpdir, checksum);
+
+ /* Make the temporary directory world readable */
+ if (chmod (tmpcd, 0755) == -1) {
+ error (g, "chmod %s: %m", tmpcd);
+ }
+
+ /* Try to rename the temporary directory to its non-temporary name */
+ if (rename (tmpcd, cachedir) == -1) {
+ /* If the cache directory now exists, we may have been racing with another
+ * libguestfs process. Check the new directory and use it if it's valid. */
+ if (errno == ENOTEMPTY || errno == EEXIST) {
+ /* Appliance cache consists of 2 files and a symlink in the cache
+ * directory. Delete them first. */
+ DIR *dir = opendir (tmpcd);
+ if (dir == NULL) {
+ error (g, "opendir %s: %m", tmpcd);
+ return -1;
+ }
+
+ int fd = dirfd (dir);
+ if (fd == -1) {
+ error (g, "dirfd: %m");
+ closedir (dir);
+ return -1;
+ }
+
+ struct dirent *dirent;
+ for (;;) {
+ errno = 0;
+ dirent = readdir (dir);
+
+ if (dirent == NULL) {
+ break;
+ }
+
+ /* Check that dirent is a file so we don't try to delete . and .. */
+ struct stat st;
+ if (fstatat (fd, dirent->d_name, &st, AT_SYMLINK_NOFOLLOW) == -1) {
+ error (g, "fstatat %s: %m", dirent->d_name);
+ return -1;
+ }
+
+ if (!S_ISDIR(st.st_mode)) {
+ if (unlinkat (fd, dirent->d_name, 0) == -1) {
+ error (g, "unlinkat %s: %m", dirent->d_name);
+ closedir (dir);
+ return -1;
+ }
+ }
+ }
+
+ if (errno != 0) {
+ error (g, "readdir %s: %m", tmpcd);
+ closedir (dir);
+ return -1;
+ }
+
+ closedir (dir);
+
+ /* Delete the temporary cache directory itself. */
+ if (rmdir (tmpcd) == -1) {
+ error (g, "rmdir %s: %m", tmpcd);
+ return -1;
+ }
+
+ /* Check the new cache directory, and return it if valid */
+ return check_for_cached_appliance (g, supermin_path, checksum,
+ kernel, initrd, appliance);
+ }
+
+ else {
+ error (g, _("error renaming temporary cache directory: %m"));
+ return -1;
+ }
+ }
+
*kernel = safe_malloc (g, cdlen + 8 /* / + "kernel" + \0 */);
*initrd = safe_malloc (g, cdlen + 8 /* / + "initrd" + \0 */);
*appliance = safe_malloc (g, cdlen + 6 /* / + "root" + \0 */);
return 0;
}
+/* Run febootstrap-supermin-helper and tell it to generate the
+ * appliance.
+ */
+static int
+run_supermin_helper (guestfs_h *g, const char *supermin_path,
+ const char *cachedir, size_t cdlen)
+{
+ size_t pathlen = strlen (supermin_path);
+
+ const char *argv[30];
+ size_t i = 0;
+
+ char uid[32];
+ snprintf (uid, sizeof uid, "%i", geteuid ());
+ char gid[32];
+ snprintf (gid, sizeof gid, "%i", getegid ());
+ char supermin_d[pathlen + 32];
+ snprintf (supermin_d, pathlen + 32, "%s/supermin.d", supermin_path);
+ char kernel[cdlen + 32];
+ snprintf (kernel, cdlen + 32, "%s/kernel", cachedir);
+ char initrd[cdlen + 32];
+ snprintf (initrd, cdlen + 32, "%s/initrd", cachedir);
+ char root[cdlen + 32];
+ snprintf (root, cdlen + 32, "%s/root", cachedir);
+
+ int pass_u_g_args = getuid () != geteuid () || getgid () != getegid ();
+
+ argv[i++] = "febootstrap-supermin-helper";
+ if (g->verbose)
+ argv[i++] = "--verbose";
+ if (pass_u_g_args) {
+ argv[i++] = "-u";
+ argv[i++] = uid;
+ argv[i++] = "-g";
+ argv[i++] = gid;
+ }
+ argv[i++] = "-f";
+ argv[i++] = "ext2";
+ argv[i++] = supermin_d;
+ argv[i++] = host_cpu;
+ argv[i++] = kernel;
+ argv[i++] = initrd;
+ argv[i++] = root;
+ argv[i++] = NULL;
+
+ pid_t pid = fork ();
+ if (pid == -1) {
+ perrorf (g, "fork");
+ return -1;
+ }
+
+ if (pid > 0) { /* Parent. */
+ if (g->verbose)
+ guestfs___print_timestamped_argv (g, argv);
+
+ int status;
+ if (waitpid (pid, &status, 0) == -1) {
+ perrorf (g, "waitpid");
+ return -1;
+ }
+ if (!WIFEXITED (status) || WEXITSTATUS (status) != 0) {
+ error (g, _("external command failed, see earlier error messages"));
+ return -1;
+ }
+ return 0;
+ }
+
+ /* Child. */
+
+ /* Set a sensible umask in the subprocess, so kernel and initrd
+ * output files are world-readable (RHBZ#610880).
+ */
+ umask (0022);
+
+ execvp ("febootstrap-supermin-helper", (char * const *) argv);
+ perror ("execvp");
+ _exit (EXIT_FAILURE);
+}
+
/* Search elements of g->path, returning the first path element which
* matches the predicate function 'pred'.
*
git.annexia.org / libguestfs.git / blobdiff