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-rw-r--r--src/libbasic/util.c793
1 files changed, 793 insertions, 0 deletions
diff --git a/src/libbasic/util.c b/src/libbasic/util.c
new file mode 100644
index 0000000000..ea1bed7ceb
--- /dev/null
+++ b/src/libbasic/util.c
@@ -0,0 +1,793 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <alloca.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/prctl.h>
+#include <sys/statfs.h>
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "build.h"
+#include "def.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "formats-util.h"
+#include "hashmap.h"
+#include "hostname-util.h"
+#include "log.h"
+#include "macro.h"
+#include "missing.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "set.h"
+#include "signal-util.h"
+#include "stat-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "time-util.h"
+#include "user-util.h"
+#include "util.h"
+
+/* Put this test here for a lack of better place */
+assert_cc(EAGAIN == EWOULDBLOCK);
+
+int saved_argc = 0;
+char **saved_argv = NULL;
+
+size_t page_size(void) {
+ static thread_local size_t pgsz = 0;
+ long r;
+
+ if (_likely_(pgsz > 0))
+ return pgsz;
+
+ r = sysconf(_SC_PAGESIZE);
+ assert(r > 0);
+
+ pgsz = (size_t) r;
+ return pgsz;
+}
+
+static int do_execute(char **directories, usec_t timeout, char *argv[]) {
+ _cleanup_hashmap_free_free_ Hashmap *pids = NULL;
+ _cleanup_set_free_free_ Set *seen = NULL;
+ char **directory;
+
+ /* We fork this all off from a child process so that we can
+ * somewhat cleanly make use of SIGALRM to set a time limit */
+
+ (void) reset_all_signal_handlers();
+ (void) reset_signal_mask();
+
+ assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
+
+ pids = hashmap_new(NULL);
+ if (!pids)
+ return log_oom();
+
+ seen = set_new(&string_hash_ops);
+ if (!seen)
+ return log_oom();
+
+ STRV_FOREACH(directory, directories) {
+ _cleanup_closedir_ DIR *d;
+ struct dirent *de;
+
+ d = opendir(*directory);
+ if (!d) {
+ if (errno == ENOENT)
+ continue;
+
+ return log_error_errno(errno, "Failed to open directory %s: %m", *directory);
+ }
+
+ FOREACH_DIRENT(de, d, break) {
+ _cleanup_free_ char *path = NULL;
+ pid_t pid;
+ int r;
+
+ if (!dirent_is_file(de))
+ continue;
+
+ if (set_contains(seen, de->d_name)) {
+ log_debug("%1$s/%2$s skipped (%2$s was already seen).", *directory, de->d_name);
+ continue;
+ }
+
+ r = set_put_strdup(seen, de->d_name);
+ if (r < 0)
+ return log_oom();
+
+ path = strjoin(*directory, "/", de->d_name, NULL);
+ if (!path)
+ return log_oom();
+
+ if (null_or_empty_path(path)) {
+ log_debug("%s is empty (a mask).", path);
+ continue;
+ }
+
+ pid = fork();
+ if (pid < 0) {
+ log_error_errno(errno, "Failed to fork: %m");
+ continue;
+ } else if (pid == 0) {
+ char *_argv[2];
+
+ assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
+
+ if (!argv) {
+ _argv[0] = path;
+ _argv[1] = NULL;
+ argv = _argv;
+ } else
+ argv[0] = path;
+
+ execv(path, argv);
+ return log_error_errno(errno, "Failed to execute %s: %m", path);
+ }
+
+ log_debug("Spawned %s as " PID_FMT ".", path, pid);
+
+ r = hashmap_put(pids, PID_TO_PTR(pid), path);
+ if (r < 0)
+ return log_oom();
+ path = NULL;
+ }
+ }
+
+ /* Abort execution of this process after the timout. We simply
+ * rely on SIGALRM as default action terminating the process,
+ * and turn on alarm(). */
+
+ if (timeout != USEC_INFINITY)
+ alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC);
+
+ while (!hashmap_isempty(pids)) {
+ _cleanup_free_ char *path = NULL;
+ pid_t pid;
+
+ pid = PTR_TO_PID(hashmap_first_key(pids));
+ assert(pid > 0);
+
+ path = hashmap_remove(pids, PID_TO_PTR(pid));
+ assert(path);
+
+ wait_for_terminate_and_warn(path, pid, true);
+ }
+
+ return 0;
+}
+
+void execute_directories(const char* const* directories, usec_t timeout, char *argv[]) {
+ pid_t executor_pid;
+ int r;
+ char *name;
+ char **dirs = (char**) directories;
+
+ assert(!strv_isempty(dirs));
+
+ name = basename(dirs[0]);
+ assert(!isempty(name));
+
+ /* Executes all binaries in the directories in parallel and waits
+ * for them to finish. Optionally a timeout is applied. If a file
+ * with the same name exists in more than one directory, the
+ * earliest one wins. */
+
+ executor_pid = fork();
+ if (executor_pid < 0) {
+ log_error_errno(errno, "Failed to fork: %m");
+ return;
+
+ } else if (executor_pid == 0) {
+ r = do_execute(dirs, timeout, argv);
+ _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+ }
+
+ wait_for_terminate_and_warn(name, executor_pid, true);
+}
+
+bool plymouth_running(void) {
+ return access("/run/plymouth/pid", F_OK) >= 0;
+}
+
+bool display_is_local(const char *display) {
+ assert(display);
+
+ return
+ display[0] == ':' &&
+ display[1] >= '0' &&
+ display[1] <= '9';
+}
+
+int socket_from_display(const char *display, char **path) {
+ size_t k;
+ char *f, *c;
+
+ assert(display);
+ assert(path);
+
+ if (!display_is_local(display))
+ return -EINVAL;
+
+ k = strspn(display+1, "0123456789");
+
+ f = new(char, strlen("/tmp/.X11-unix/X") + k + 1);
+ if (!f)
+ return -ENOMEM;
+
+ c = stpcpy(f, "/tmp/.X11-unix/X");
+ memcpy(c, display+1, k);
+ c[k] = 0;
+
+ *path = f;
+
+ return 0;
+}
+
+int block_get_whole_disk(dev_t d, dev_t *ret) {
+ char *p, *s;
+ int r;
+ unsigned n, m;
+
+ assert(ret);
+
+ /* If it has a queue this is good enough for us */
+ if (asprintf(&p, "/sys/dev/block/%u:%u/queue", major(d), minor(d)) < 0)
+ return -ENOMEM;
+
+ r = access(p, F_OK);
+ free(p);
+
+ if (r >= 0) {
+ *ret = d;
+ return 0;
+ }
+
+ /* If it is a partition find the originating device */
+ if (asprintf(&p, "/sys/dev/block/%u:%u/partition", major(d), minor(d)) < 0)
+ return -ENOMEM;
+
+ r = access(p, F_OK);
+ free(p);
+
+ if (r < 0)
+ return -ENOENT;
+
+ /* Get parent dev_t */
+ if (asprintf(&p, "/sys/dev/block/%u:%u/../dev", major(d), minor(d)) < 0)
+ return -ENOMEM;
+
+ r = read_one_line_file(p, &s);
+ free(p);
+
+ if (r < 0)
+ return r;
+
+ r = sscanf(s, "%u:%u", &m, &n);
+ free(s);
+
+ if (r != 2)
+ return -EINVAL;
+
+ /* Only return this if it is really good enough for us. */
+ if (asprintf(&p, "/sys/dev/block/%u:%u/queue", m, n) < 0)
+ return -ENOMEM;
+
+ r = access(p, F_OK);
+ free(p);
+
+ if (r >= 0) {
+ *ret = makedev(m, n);
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+bool kexec_loaded(void) {
+ bool loaded = false;
+ char *s;
+
+ if (read_one_line_file("/sys/kernel/kexec_loaded", &s) >= 0) {
+ if (s[0] == '1')
+ loaded = true;
+ free(s);
+ }
+ return loaded;
+}
+
+int prot_from_flags(int flags) {
+
+ switch (flags & O_ACCMODE) {
+
+ case O_RDONLY:
+ return PROT_READ;
+
+ case O_WRONLY:
+ return PROT_WRITE;
+
+ case O_RDWR:
+ return PROT_READ|PROT_WRITE;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *path, ...) {
+ bool stdout_is_tty, stderr_is_tty;
+ pid_t parent_pid, agent_pid;
+ sigset_t ss, saved_ss;
+ unsigned n, i;
+ va_list ap;
+ char **l;
+
+ assert(pid);
+ assert(path);
+
+ /* Spawns a temporary TTY agent, making sure it goes away when
+ * we go away */
+
+ parent_pid = getpid();
+
+ /* First we temporarily block all signals, so that the new
+ * child has them blocked initially. This way, we can be sure
+ * that SIGTERMs are not lost we might send to the agent. */
+ assert_se(sigfillset(&ss) >= 0);
+ assert_se(sigprocmask(SIG_SETMASK, &ss, &saved_ss) >= 0);
+
+ agent_pid = fork();
+ if (agent_pid < 0) {
+ assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0);
+ return -errno;
+ }
+
+ if (agent_pid != 0) {
+ assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0);
+ *pid = agent_pid;
+ return 0;
+ }
+
+ /* In the child:
+ *
+ * Make sure the agent goes away when the parent dies */
+ if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
+ _exit(EXIT_FAILURE);
+
+ /* Make sure we actually can kill the agent, if we need to, in
+ * case somebody invoked us from a shell script that trapped
+ * SIGTERM or so... */
+ (void) reset_all_signal_handlers();
+ (void) reset_signal_mask();
+
+ /* Check whether our parent died before we were able
+ * to set the death signal and unblock the signals */
+ if (getppid() != parent_pid)
+ _exit(EXIT_SUCCESS);
+
+ /* Don't leak fds to the agent */
+ close_all_fds(except, n_except);
+
+ stdout_is_tty = isatty(STDOUT_FILENO);
+ stderr_is_tty = isatty(STDERR_FILENO);
+
+ if (!stdout_is_tty || !stderr_is_tty) {
+ int fd;
+
+ /* Detach from stdout/stderr. and reopen
+ * /dev/tty for them. This is important to
+ * ensure that when systemctl is started via
+ * popen() or a similar call that expects to
+ * read EOF we actually do generate EOF and
+ * not delay this indefinitely by because we
+ * keep an unused copy of stdin around. */
+ fd = open("/dev/tty", O_WRONLY);
+ if (fd < 0) {
+ log_error_errno(errno, "Failed to open /dev/tty: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ if (!stdout_is_tty)
+ dup2(fd, STDOUT_FILENO);
+
+ if (!stderr_is_tty)
+ dup2(fd, STDERR_FILENO);
+
+ if (fd > 2)
+ close(fd);
+ }
+
+ /* Count arguments */
+ va_start(ap, path);
+ for (n = 0; va_arg(ap, char*); n++)
+ ;
+ va_end(ap);
+
+ /* Allocate strv */
+ l = alloca(sizeof(char *) * (n + 1));
+
+ /* Fill in arguments */
+ va_start(ap, path);
+ for (i = 0; i <= n; i++)
+ l[i] = va_arg(ap, char*);
+ va_end(ap);
+
+ execv(path, l);
+ _exit(EXIT_FAILURE);
+}
+
+bool in_initrd(void) {
+ static int saved = -1;
+ struct statfs s;
+
+ if (saved >= 0)
+ return saved;
+
+ /* We make two checks here:
+ *
+ * 1. the flag file /etc/initrd-release must exist
+ * 2. the root file system must be a memory file system
+ *
+ * The second check is extra paranoia, since misdetecting an
+ * initrd can have bad bad consequences due the initrd
+ * emptying when transititioning to the main systemd.
+ */
+
+ saved = access("/etc/initrd-release", F_OK) >= 0 &&
+ statfs("/", &s) >= 0 &&
+ is_temporary_fs(&s);
+
+ return saved;
+}
+
+/* hey glibc, APIs with callbacks without a user pointer are so useless */
+void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
+ int (*compar) (const void *, const void *, void *), void *arg) {
+ size_t l, u, idx;
+ const void *p;
+ int comparison;
+
+ l = 0;
+ u = nmemb;
+ while (l < u) {
+ idx = (l + u) / 2;
+ p = (void *)(((const char *) base) + (idx * size));
+ comparison = compar(key, p, arg);
+ if (comparison < 0)
+ u = idx;
+ else if (comparison > 0)
+ l = idx + 1;
+ else
+ return (void *)p;
+ }
+ return NULL;
+}
+
+int on_ac_power(void) {
+ bool found_offline = false, found_online = false;
+ _cleanup_closedir_ DIR *d = NULL;
+
+ d = opendir("/sys/class/power_supply");
+ if (!d)
+ return errno == ENOENT ? true : -errno;
+
+ for (;;) {
+ struct dirent *de;
+ _cleanup_close_ int fd = -1, device = -1;
+ char contents[6];
+ ssize_t n;
+
+ errno = 0;
+ de = readdir(d);
+ if (!de && errno > 0)
+ return -errno;
+
+ if (!de)
+ break;
+
+ if (hidden_file(de->d_name))
+ continue;
+
+ device = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (device < 0) {
+ if (errno == ENOENT || errno == ENOTDIR)
+ continue;
+
+ return -errno;
+ }
+
+ fd = openat(device, "type", O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0) {
+ if (errno == ENOENT)
+ continue;
+
+ return -errno;
+ }
+
+ n = read(fd, contents, sizeof(contents));
+ if (n < 0)
+ return -errno;
+
+ if (n != 6 || memcmp(contents, "Mains\n", 6))
+ continue;
+
+ safe_close(fd);
+ fd = openat(device, "online", O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0) {
+ if (errno == ENOENT)
+ continue;
+
+ return -errno;
+ }
+
+ n = read(fd, contents, sizeof(contents));
+ if (n < 0)
+ return -errno;
+
+ if (n != 2 || contents[1] != '\n')
+ return -EIO;
+
+ if (contents[0] == '1') {
+ found_online = true;
+ break;
+ } else if (contents[0] == '0')
+ found_offline = true;
+ else
+ return -EIO;
+ }
+
+ return found_online || !found_offline;
+}
+
+bool id128_is_valid(const char *s) {
+ size_t i, l;
+
+ l = strlen(s);
+ if (l == 32) {
+
+ /* Simple formatted 128bit hex string */
+
+ for (i = 0; i < l; i++) {
+ char c = s[i];
+
+ if (!(c >= '0' && c <= '9') &&
+ !(c >= 'a' && c <= 'z') &&
+ !(c >= 'A' && c <= 'Z'))
+ return false;
+ }
+
+ } else if (l == 36) {
+
+ /* Formatted UUID */
+
+ for (i = 0; i < l; i++) {
+ char c = s[i];
+
+ if ((i == 8 || i == 13 || i == 18 || i == 23)) {
+ if (c != '-')
+ return false;
+ } else {
+ if (!(c >= '0' && c <= '9') &&
+ !(c >= 'a' && c <= 'z') &&
+ !(c >= 'A' && c <= 'Z'))
+ return false;
+ }
+ }
+
+ } else
+ return false;
+
+ return true;
+}
+
+int container_get_leader(const char *machine, pid_t *pid) {
+ _cleanup_free_ char *s = NULL, *class = NULL;
+ const char *p;
+ pid_t leader;
+ int r;
+
+ assert(machine);
+ assert(pid);
+
+ if (!machine_name_is_valid(machine))
+ return -EINVAL;
+
+ p = strjoina("/run/systemd/machines/", machine);
+ r = parse_env_file(p, NEWLINE, "LEADER", &s, "CLASS", &class, NULL);
+ if (r == -ENOENT)
+ return -EHOSTDOWN;
+ if (r < 0)
+ return r;
+ if (!s)
+ return -EIO;
+
+ if (!streq_ptr(class, "container"))
+ return -EIO;
+
+ r = parse_pid(s, &leader);
+ if (r < 0)
+ return r;
+ if (leader <= 1)
+ return -EIO;
+
+ *pid = leader;
+ return 0;
+}
+
+int namespace_open(pid_t pid, int *pidns_fd, int *mntns_fd, int *netns_fd, int *userns_fd, int *root_fd) {
+ _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, netnsfd = -1, usernsfd = -1;
+ int rfd = -1;
+
+ assert(pid >= 0);
+
+ if (mntns_fd) {
+ const char *mntns;
+
+ mntns = procfs_file_alloca(pid, "ns/mnt");
+ mntnsfd = open(mntns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+ if (mntnsfd < 0)
+ return -errno;
+ }
+
+ if (pidns_fd) {
+ const char *pidns;
+
+ pidns = procfs_file_alloca(pid, "ns/pid");
+ pidnsfd = open(pidns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+ if (pidnsfd < 0)
+ return -errno;
+ }
+
+ if (netns_fd) {
+ const char *netns;
+
+ netns = procfs_file_alloca(pid, "ns/net");
+ netnsfd = open(netns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+ if (netnsfd < 0)
+ return -errno;
+ }
+
+ if (userns_fd) {
+ const char *userns;
+
+ userns = procfs_file_alloca(pid, "ns/user");
+ usernsfd = open(userns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+ if (usernsfd < 0 && errno != ENOENT)
+ return -errno;
+ }
+
+ if (root_fd) {
+ const char *root;
+
+ root = procfs_file_alloca(pid, "root");
+ rfd = open(root, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
+ if (rfd < 0)
+ return -errno;
+ }
+
+ if (pidns_fd)
+ *pidns_fd = pidnsfd;
+
+ if (mntns_fd)
+ *mntns_fd = mntnsfd;
+
+ if (netns_fd)
+ *netns_fd = netnsfd;
+
+ if (userns_fd)
+ *userns_fd = usernsfd;
+
+ if (root_fd)
+ *root_fd = rfd;
+
+ pidnsfd = mntnsfd = netnsfd = usernsfd = -1;
+
+ return 0;
+}
+
+int namespace_enter(int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int root_fd) {
+ if (userns_fd >= 0) {
+ /* Can't setns to your own userns, since then you could
+ * escalate from non-root to root in your own namespace, so
+ * check if namespaces equal before attempting to enter. */
+ _cleanup_free_ char *userns_fd_path = NULL;
+ int r;
+ if (asprintf(&userns_fd_path, "/proc/self/fd/%d", userns_fd) < 0)
+ return -ENOMEM;
+
+ r = files_same(userns_fd_path, "/proc/self/ns/user");
+ if (r < 0)
+ return r;
+ if (r)
+ userns_fd = -1;
+ }
+
+ if (pidns_fd >= 0)
+ if (setns(pidns_fd, CLONE_NEWPID) < 0)
+ return -errno;
+
+ if (mntns_fd >= 0)
+ if (setns(mntns_fd, CLONE_NEWNS) < 0)
+ return -errno;
+
+ if (netns_fd >= 0)
+ if (setns(netns_fd, CLONE_NEWNET) < 0)
+ return -errno;
+
+ if (userns_fd >= 0)
+ if (setns(userns_fd, CLONE_NEWUSER) < 0)
+ return -errno;
+
+ if (root_fd >= 0) {
+ if (fchdir(root_fd) < 0)
+ return -errno;
+
+ if (chroot(".") < 0)
+ return -errno;
+ }
+
+ return reset_uid_gid();
+}
+
+uint64_t physical_memory(void) {
+ long mem;
+
+ /* We return this as uint64_t in case we are running as 32bit
+ * process on a 64bit kernel with huge amounts of memory */
+
+ mem = sysconf(_SC_PHYS_PAGES);
+ assert(mem > 0);
+
+ return (uint64_t) mem * (uint64_t) page_size();
+}
+
+int update_reboot_param_file(const char *param) {
+ int r = 0;
+
+ if (param) {
+ r = write_string_file(REBOOT_PARAM_FILE, param, WRITE_STRING_FILE_CREATE);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write reboot param to "REBOOT_PARAM_FILE": %m");
+ } else
+ (void) unlink(REBOOT_PARAM_FILE);
+
+ return 0;
+}
+
+int version(void) {
+ puts(PACKAGE_STRING "\n"
+ SYSTEMD_FEATURES);
+ return 0;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-01 01:07:27 +0000