CAP_SYS_RESOURCE.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>--link-journal=</option></term>
+
+ <listitem><para>Control whether the
+ container's journal shall be made
+ visible to the host system. If enabled
+ allows viewing the container's journal
+ files from the host (but not vice
+ versa). Takes one of
+ <literal>no</literal>,
+ <literal>host</literal>,
+ <literal>guest</literal>,
+ <literal>auto</literal>. If
+ <literal>no</literal> the journal is
+ not linked. If <literal>host</literal>
+ the journal files are stored on the
+ host file system (beneath the host's
+ <filename>/var/log/journal</filename>)
+ and a per-machine subdirectory of this
+ directory is created and bind mounted
+ into the container at the same
+ location. If <literal>guest</literal>
+ the journal files are stored on the
+ guest file system (beneath the guest's
+ <filename>/var/log/journal</filename>)
+ and a per-machine subdirectory of this
+ directory is symlinked into the host
+ at the same location. If
+ <literal>auto</literal> (the default)
+ and the subdirectory of
+ <filename>/var/log/journal</filename>
+ exists as directory it is bind mounted
+ into the container, but nothing is
+ done otherwise. Effectively, booting a
+ container once with
+ <literal>guest</literal> or
+ <literal>host</literal> will link the
+ journal persistantly if further one
+ the default of <literal>auto</literal>
+ is used.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>-j</option></term>
+
+ <listitem><para>Equivalent to
+ <option>--link-journal=guest</option>.</para></listitem>
+ </varlistentry>
</variablelist>
</refsect1>
#include "strv.h"
#include "path-util.h"
#include "loopback-setup.h"
+#include "sd-id128.h"
+
+typedef enum LinkJournal {
+ LINK_NO,
+ LINK_AUTO,
+ LINK_HOST,
+ LINK_GUEST
+} LinkJournal;
static char *arg_directory = NULL;
static char *arg_user = NULL;
static bool arg_private_network = false;
static bool arg_read_only = false;
static bool arg_boot = false;
+static LinkJournal arg_link_journal = LINK_AUTO;
static uint64_t arg_retain =
(1ULL << CAP_CHOWN) |
(1ULL << CAP_DAC_OVERRIDE) |
printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
"Spawn a minimal namespace container for debugging, testing and building.\n\n"
- " -h --help Show this help\n"
- " -D --directory=NAME Root directory for the container\n"
- " -b --boot Boot up full system (i.e. invoke init)\n"
- " -u --user=USER Run the command under specified user or uid\n"
- " -C --controllers=LIST Put the container in specified comma-separated cgroup hierarchies\n"
- " --uuid=UUID Set a specific machine UUID for the container\n"
- " --private-network Disable network in container\n"
- " --read-only Mount the root directory read-only\n"
- " --capability=CAP In addition to the default, retain specified capability\n",
+ " -h --help Show this help\n"
+ " -D --directory=NAME Root directory for the container\n"
+ " -b --boot Boot up full system (i.e. invoke init)\n"
+ " -u --user=USER Run the command under specified user or uid\n"
+ " -C --controllers=LIST Put the container in specified comma-separated cgroup hierarchies\n"
+ " --uuid=UUID Set a specific machine UUID for the container\n"
+ " --private-network Disable network in container\n"
+ " --read-only Mount the root directory read-only\n"
+ " --capability=CAP In addition to the default, retain specified capability\n"
+ " --link-journal=MODE Link up guest journal, one of no, auto, guest, host\n"
+ " -j Equivalent to --link-journal=host\n",
program_invocation_short_name);
return 0;
ARG_PRIVATE_NETWORK = 0x100,
ARG_UUID,
ARG_READ_ONLY,
- ARG_CAPABILITY
+ ARG_CAPABILITY,
+ ARG_LINK_JOURNAL
};
static const struct option options[] = {
{ "uuid", required_argument, NULL, ARG_UUID },
{ "read-only", no_argument, NULL, ARG_READ_ONLY },
{ "capability", required_argument, NULL, ARG_CAPABILITY },
+ { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
{ NULL, 0, NULL, 0 }
};
assert(argc >= 0);
assert(argv);
- while ((c = getopt_long(argc, argv, "+hD:u:C:b", options, NULL)) >= 0) {
+ while ((c = getopt_long(argc, argv, "+hD:u:C:bj", options, NULL)) >= 0) {
switch (c) {
break;
}
+ case 'j':
+ arg_link_journal = LINK_GUEST;
+ break;
+
+ case ARG_LINK_JOURNAL:
+ if (streq(optarg, "auto"))
+ arg_link_journal = LINK_AUTO;
+ else if (streq(optarg, "no"))
+ arg_link_journal = LINK_NO;
+ else if (streq(optarg, "guest"))
+ arg_link_journal = LINK_GUEST;
+ else if (streq(optarg, "host"))
+ arg_link_journal = LINK_HOST;
+ else {
+ log_error("Failed to parse link journal mode %s", optarg);
+ return -EINVAL;
+ }
+
+ break;
+
case '?':
return -EINVAL;
return r;
}
+static int setup_journal(const char *directory) {
+ sd_id128_t machine_id;
+ char *p = NULL, *b = NULL, *l, *q = NULL, *d = NULL;
+ int r;
+
+ if (arg_link_journal == LINK_NO)
+ return 0;
+
+ p = strappend(directory, "/etc/machine-id");
+ if (!p) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ r = read_one_line_file(p, &b);
+ if (r == -ENOENT && arg_link_journal == LINK_AUTO) {
+ r = 0;
+ goto finish;
+ } else if (r < 0) {
+ log_error("Failed to read machine ID: %s", strerror(-r));
+ return r;
+ }
+
+ l = strstrip(b);
+ if (isempty(l) && arg_link_journal == LINK_AUTO) {
+ r = 0;
+ goto finish;
+ }
+
+ /* Verify validaty */
+ r = sd_id128_from_string(l, &machine_id);
+ if (r < 0) {
+ log_error("Failed to parse machine ID: %s", strerror(-r));
+ goto finish;
+ }
+
+ free(p);
+ p = strappend("/var/log/journal/", l);
+ q = strjoin(directory, "/var/log/journal/", l, NULL);
+ if (!p || !q) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ if (path_is_mount_point(p, false) > 0 ||
+ path_is_mount_point(q, false) > 0) {
+ if (arg_link_journal != LINK_AUTO) {
+ log_error("Journal already a mount point, refusing.");
+ r = -EEXIST;
+ goto finish;
+ }
+
+ r = 0;
+ goto finish;
+ }
+
+ r = readlink_and_make_absolute(p, &d);
+ if (r >= 0) {
+ if ((arg_link_journal == LINK_GUEST ||
+ arg_link_journal == LINK_AUTO) &&
+ path_equal(d, q)) {
+
+ mkdir_p(q, 0755);
+
+ r = 0;
+ goto finish;
+ }
+
+ if (unlink(p) < 0) {
+ log_error("Failed to remove symlink %s: %m", p);
+ r = -errno;
+ goto finish;
+ }
+ } else if (r == -EINVAL) {
+
+ if (arg_link_journal == LINK_GUEST &&
+ rmdir(p) < 0) {
+
+ if (errno == ENOTDIR)
+ log_error("%s already exists and is neither symlink nor directory.", p);
+ else {
+ log_error("Failed to remove %s: %m", p);
+ r = -errno;
+ }
+
+ goto finish;
+ }
+ } else if (r != -ENOENT) {
+ log_error("readlink(%s) failed: %m", p);
+ goto finish;
+ }
+
+ if (arg_link_journal == LINK_GUEST) {
+
+ if (symlink(q, p) < 0) {
+ log_error("Failed to symlink %s to %s: %m", q, p);
+ r = -errno;
+ goto finish;
+ }
+
+ mkdir_p(q, 0755);
+
+ r = 0;
+ goto finish;
+ }
+
+ if (arg_link_journal == LINK_HOST) {
+ r = mkdir_p(p, 0755);
+ if (r < 0) {
+ log_error("Failed to create %s: %m", p);
+ goto finish;
+ }
+
+ } else if (access(p, F_OK) < 0) {
+ r = 0;
+ goto finish;
+ }
+
+ if (dir_is_empty(q) == 0) {
+ log_error("%s not empty.", q);
+ r = -ENOTEMPTY;
+ goto finish;
+ }
+
+ r = mkdir_p(q, 0755);
+ if (r < 0) {
+ log_error("Failed to create %s: %m", q);
+ goto finish;
+ }
+
+ if (mount(p, q, "bind", MS_BIND, NULL) < 0) {
+ log_error("Failed to bind mount journal from host into guest: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ r = 0;
+
+finish:
+ free(p);
+ free(q);
+ free(d);
+ free(b);
+ return r;
+
+}
+
static int drop_capabilities(void) {
return capability_bounding_set_drop(~arg_retain, false);
}
if (setup_resolv_conf(arg_directory) < 0)
goto child_fail;
+ if (setup_journal(arg_directory) < 0)
+ goto child_fail;
+
if (chdir(arg_directory) < 0) {
log_error("chdir(%s) failed: %m", arg_directory);
goto child_fail;
~ianmdlvl / elogind.git / commitdiff