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Diffstat (limited to 'src/libsystemd/sd-daemon/sd-daemon.c')
-rw-r--r--src/libsystemd/sd-daemon/sd-daemon.c676
1 files changed, 676 insertions, 0 deletions
diff --git a/src/libsystemd/sd-daemon/sd-daemon.c b/src/libsystemd/sd-daemon/sd-daemon.c
new file mode 100644
index 0000000..199d10a
--- /dev/null
+++ b/src/libsystemd/sd-daemon/sd-daemon.c
@@ -0,0 +1,676 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <limits.h>
+#include <mqueue.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "sd-daemon.h"
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "fs-util.h"
+#include "io-util.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "socket-util.h"
+#include "stat-util.h"
+#include "strv.h"
+#include "time-util.h"
+#include "util.h"
+
+#define SNDBUF_SIZE (8*1024*1024)
+
+static void unsetenv_all(bool unset_environment) {
+ if (!unset_environment)
+ return;
+
+ assert_se(unsetenv("LISTEN_PID") == 0);
+ assert_se(unsetenv("LISTEN_FDS") == 0);
+ assert_se(unsetenv("LISTEN_FDNAMES") == 0);
+}
+
+_public_ int sd_listen_fds(int unset_environment) {
+ const char *e;
+ int n, r;
+ pid_t pid;
+
+ e = getenv("LISTEN_PID");
+ if (!e) {
+ r = 0;
+ goto finish;
+ }
+
+ r = parse_pid(e, &pid);
+ if (r < 0)
+ goto finish;
+
+ /* Is this for us? */
+ if (getpid_cached() != pid) {
+ r = 0;
+ goto finish;
+ }
+
+ e = getenv("LISTEN_FDS");
+ if (!e) {
+ r = 0;
+ goto finish;
+ }
+
+ r = safe_atoi(e, &n);
+ if (r < 0)
+ goto finish;
+
+ assert_cc(SD_LISTEN_FDS_START < INT_MAX);
+ if (n <= 0 || n > INT_MAX - SD_LISTEN_FDS_START) {
+ r = -EINVAL;
+ goto finish;
+ }
+
+ for (int fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd ++) {
+ r = fd_cloexec(fd, true);
+ if (r < 0)
+ goto finish;
+ }
+
+ r = n;
+
+finish:
+ unsetenv_all(unset_environment);
+ return r;
+}
+
+_public_ int sd_listen_fds_with_names(int unset_environment, char ***names) {
+ _cleanup_strv_free_ char **l = NULL;
+ bool have_names;
+ int n_names = 0, n_fds;
+ const char *e;
+ int r;
+
+ if (!names)
+ return sd_listen_fds(unset_environment);
+
+ e = getenv("LISTEN_FDNAMES");
+ if (e) {
+ n_names = strv_split_full(&l, e, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+ if (n_names < 0) {
+ unsetenv_all(unset_environment);
+ return n_names;
+ }
+
+ have_names = true;
+ } else
+ have_names = false;
+
+ n_fds = sd_listen_fds(unset_environment);
+ if (n_fds <= 0)
+ return n_fds;
+
+ if (have_names) {
+ if (n_names != n_fds)
+ return -EINVAL;
+ } else {
+ r = strv_extend_n(&l, "unknown", n_fds);
+ if (r < 0)
+ return r;
+ }
+
+ *names = TAKE_PTR(l);
+
+ return n_fds;
+}
+
+_public_ int sd_is_fifo(int fd, const char *path) {
+ struct stat st_fd;
+
+ assert_return(fd >= 0, -EBADF);
+
+ if (fstat(fd, &st_fd) < 0)
+ return -errno;
+
+ if (!S_ISFIFO(st_fd.st_mode))
+ return 0;
+
+ if (path) {
+ struct stat st_path;
+
+ if (stat(path, &st_path) < 0) {
+
+ if (IN_SET(errno, ENOENT, ENOTDIR))
+ return 0;
+
+ return -errno;
+ }
+
+ return stat_inode_same(&st_path, &st_fd);
+ }
+
+ return 1;
+}
+
+_public_ int sd_is_special(int fd, const char *path) {
+ struct stat st_fd;
+
+ assert_return(fd >= 0, -EBADF);
+
+ if (fstat(fd, &st_fd) < 0)
+ return -errno;
+
+ if (!S_ISREG(st_fd.st_mode) && !S_ISCHR(st_fd.st_mode))
+ return 0;
+
+ if (path) {
+ struct stat st_path;
+
+ if (stat(path, &st_path) < 0) {
+
+ if (IN_SET(errno, ENOENT, ENOTDIR))
+ return 0;
+
+ return -errno;
+ }
+
+ if (S_ISREG(st_fd.st_mode) && S_ISREG(st_path.st_mode))
+ return stat_inode_same(&st_path, &st_fd);
+ else if (S_ISCHR(st_fd.st_mode) && S_ISCHR(st_path.st_mode))
+ return st_path.st_rdev == st_fd.st_rdev;
+ else
+ return 0;
+ }
+
+ return 1;
+}
+
+static int is_socket_internal(int fd, int type, int listening) {
+ struct stat st_fd;
+
+ assert_return(fd >= 0, -EBADF);
+ assert_return(type >= 0, -EINVAL);
+
+ if (fstat(fd, &st_fd) < 0)
+ return -errno;
+
+ if (!S_ISSOCK(st_fd.st_mode))
+ return 0;
+
+ if (type != 0) {
+ int other_type = 0;
+ socklen_t l = sizeof(other_type);
+
+ if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &other_type, &l) < 0)
+ return -errno;
+
+ if (l != sizeof(other_type))
+ return -EINVAL;
+
+ if (other_type != type)
+ return 0;
+ }
+
+ if (listening >= 0) {
+ int accepting = 0;
+ socklen_t l = sizeof(accepting);
+
+ if (getsockopt(fd, SOL_SOCKET, SO_ACCEPTCONN, &accepting, &l) < 0)
+ return -errno;
+
+ if (l != sizeof(accepting))
+ return -EINVAL;
+
+ if (!accepting != !listening)
+ return 0;
+ }
+
+ return 1;
+}
+
+_public_ int sd_is_socket(int fd, int family, int type, int listening) {
+ int r;
+
+ assert_return(fd >= 0, -EBADF);
+ assert_return(family >= 0, -EINVAL);
+
+ r = is_socket_internal(fd, type, listening);
+ if (r <= 0)
+ return r;
+
+ if (family > 0) {
+ union sockaddr_union sockaddr = {};
+ socklen_t l = sizeof(sockaddr);
+
+ if (getsockname(fd, &sockaddr.sa, &l) < 0)
+ return -errno;
+
+ if (l < sizeof(sa_family_t))
+ return -EINVAL;
+
+ return sockaddr.sa.sa_family == family;
+ }
+
+ return 1;
+}
+
+_public_ int sd_is_socket_inet(int fd, int family, int type, int listening, uint16_t port) {
+ union sockaddr_union sockaddr = {};
+ socklen_t l = sizeof(sockaddr);
+ int r;
+
+ assert_return(fd >= 0, -EBADF);
+ assert_return(IN_SET(family, 0, AF_INET, AF_INET6), -EINVAL);
+
+ r = is_socket_internal(fd, type, listening);
+ if (r <= 0)
+ return r;
+
+ if (getsockname(fd, &sockaddr.sa, &l) < 0)
+ return -errno;
+
+ if (l < sizeof(sa_family_t))
+ return -EINVAL;
+
+ if (!IN_SET(sockaddr.sa.sa_family, AF_INET, AF_INET6))
+ return 0;
+
+ if (family != 0)
+ if (sockaddr.sa.sa_family != family)
+ return 0;
+
+ if (port > 0) {
+ unsigned sa_port;
+
+ r = sockaddr_port(&sockaddr.sa, &sa_port);
+ if (r < 0)
+ return r;
+
+ return port == sa_port;
+ }
+
+ return 1;
+}
+
+_public_ int sd_is_socket_sockaddr(int fd, int type, const struct sockaddr* addr, unsigned addr_len, int listening) {
+ union sockaddr_union sockaddr = {};
+ socklen_t l = sizeof(sockaddr);
+ int r;
+
+ assert_return(fd >= 0, -EBADF);
+ assert_return(addr, -EINVAL);
+ assert_return(addr_len >= sizeof(sa_family_t), -ENOBUFS);
+ assert_return(IN_SET(addr->sa_family, AF_INET, AF_INET6), -EPFNOSUPPORT);
+
+ r = is_socket_internal(fd, type, listening);
+ if (r <= 0)
+ return r;
+
+ if (getsockname(fd, &sockaddr.sa, &l) < 0)
+ return -errno;
+
+ if (l < sizeof(sa_family_t))
+ return -EINVAL;
+
+ if (sockaddr.sa.sa_family != addr->sa_family)
+ return 0;
+
+ if (sockaddr.sa.sa_family == AF_INET) {
+ const struct sockaddr_in *in = (const struct sockaddr_in *) addr;
+
+ if (l < sizeof(struct sockaddr_in) || addr_len < sizeof(struct sockaddr_in))
+ return -EINVAL;
+
+ if (in->sin_port != 0 &&
+ sockaddr.in.sin_port != in->sin_port)
+ return false;
+
+ return sockaddr.in.sin_addr.s_addr == in->sin_addr.s_addr;
+
+ } else {
+ const struct sockaddr_in6 *in = (const struct sockaddr_in6 *) addr;
+
+ if (l < sizeof(struct sockaddr_in6) || addr_len < sizeof(struct sockaddr_in6))
+ return -EINVAL;
+
+ if (in->sin6_port != 0 &&
+ sockaddr.in6.sin6_port != in->sin6_port)
+ return false;
+
+ if (in->sin6_flowinfo != 0 &&
+ sockaddr.in6.sin6_flowinfo != in->sin6_flowinfo)
+ return false;
+
+ if (in->sin6_scope_id != 0 &&
+ sockaddr.in6.sin6_scope_id != in->sin6_scope_id)
+ return false;
+
+ return memcmp(sockaddr.in6.sin6_addr.s6_addr, in->sin6_addr.s6_addr,
+ sizeof(in->sin6_addr.s6_addr)) == 0;
+ }
+}
+
+_public_ int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length) {
+ union sockaddr_union sockaddr = {};
+ socklen_t l = sizeof(sockaddr);
+ int r;
+
+ assert_return(fd >= 0, -EBADF);
+
+ r = is_socket_internal(fd, type, listening);
+ if (r <= 0)
+ return r;
+
+ if (getsockname(fd, &sockaddr.sa, &l) < 0)
+ return -errno;
+
+ if (l < sizeof(sa_family_t))
+ return -EINVAL;
+
+ if (sockaddr.sa.sa_family != AF_UNIX)
+ return 0;
+
+ if (path) {
+ if (length == 0)
+ length = strlen(path);
+
+ if (length == 0)
+ /* Unnamed socket */
+ return l == offsetof(struct sockaddr_un, sun_path);
+
+ if (path[0])
+ /* Normal path socket */
+ return
+ (l >= offsetof(struct sockaddr_un, sun_path) + length + 1) &&
+ memcmp(path, sockaddr.un.sun_path, length+1) == 0;
+ else
+ /* Abstract namespace socket */
+ return
+ (l == offsetof(struct sockaddr_un, sun_path) + length) &&
+ memcmp(path, sockaddr.un.sun_path, length) == 0;
+ }
+
+ return 1;
+}
+
+_public_ int sd_is_mq(int fd, const char *path) {
+ struct mq_attr attr;
+
+ /* Check that the fd is valid */
+ assert_return(fcntl(fd, F_GETFD) >= 0, -errno);
+
+ if (mq_getattr(fd, &attr) < 0) {
+ if (errno == EBADF)
+ /* A non-mq fd (or an invalid one, but we ruled that out above) */
+ return 0;
+ return -errno;
+ }
+
+ if (path) {
+ _cleanup_free_ char *fpath = NULL;
+ struct stat a, b;
+
+ assert_return(path_is_absolute(path), -EINVAL);
+
+ if (fstat(fd, &a) < 0)
+ return -errno;
+
+ fpath = path_join("/dev/mqueue", path);
+ if (!fpath)
+ return -ENOMEM;
+
+ if (stat(fpath, &b) < 0)
+ return -errno;
+
+ if (!stat_inode_same(&a, &b))
+ return 0;
+ }
+
+ return 1;
+}
+
+_public_ int sd_pid_notify_with_fds(
+ pid_t pid,
+ int unset_environment,
+ const char *state,
+ const int *fds,
+ unsigned n_fds) {
+
+ union sockaddr_union sockaddr;
+ struct iovec iovec;
+ struct msghdr msghdr = {
+ .msg_iov = &iovec,
+ .msg_iovlen = 1,
+ .msg_name = &sockaddr,
+ };
+ _cleanup_close_ int fd = -1;
+ struct cmsghdr *cmsg = NULL;
+ const char *e;
+ bool send_ucred;
+ int r;
+
+ if (!state) {
+ r = -EINVAL;
+ goto finish;
+ }
+
+ if (n_fds > 0 && !fds) {
+ r = -EINVAL;
+ goto finish;
+ }
+
+ e = getenv("NOTIFY_SOCKET");
+ if (!e)
+ return 0;
+
+ r = sockaddr_un_set_path(&sockaddr.un, e);
+ if (r < 0)
+ goto finish;
+ msghdr.msg_namelen = r;
+
+ fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+ if (fd < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
+
+ iovec = IOVEC_MAKE_STRING(state);
+
+ send_ucred =
+ (pid != 0 && pid != getpid_cached()) ||
+ getuid() != geteuid() ||
+ getgid() != getegid();
+
+ if (n_fds > 0 || send_ucred) {
+ /* CMSG_SPACE(0) may return value different than zero, which results in miscalculated controllen. */
+ msghdr.msg_controllen =
+ (n_fds > 0 ? CMSG_SPACE(sizeof(int) * n_fds) : 0) +
+ (send_ucred ? CMSG_SPACE(sizeof(struct ucred)) : 0);
+
+ msghdr.msg_control = alloca0(msghdr.msg_controllen);
+
+ cmsg = CMSG_FIRSTHDR(&msghdr);
+ if (n_fds > 0) {
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(int) * n_fds);
+
+ memcpy(CMSG_DATA(cmsg), fds, sizeof(int) * n_fds);
+
+ if (send_ucred)
+ assert_se(cmsg = CMSG_NXTHDR(&msghdr, cmsg));
+ }
+
+ if (send_ucred) {
+ struct ucred *ucred;
+
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_CREDENTIALS;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
+
+ ucred = (struct ucred*) CMSG_DATA(cmsg);
+ ucred->pid = pid != 0 ? pid : getpid_cached();
+ ucred->uid = getuid();
+ ucred->gid = getgid();
+ }
+ }
+
+ /* First try with fake ucred data, as requested */
+ if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) >= 0) {
+ r = 1;
+ goto finish;
+ }
+
+ /* If that failed, try with our own ucred instead */
+ if (send_ucred) {
+ msghdr.msg_controllen -= CMSG_SPACE(sizeof(struct ucred));
+ if (msghdr.msg_controllen == 0)
+ msghdr.msg_control = NULL;
+
+ if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) >= 0) {
+ r = 1;
+ goto finish;
+ }
+ }
+
+ r = -errno;
+
+finish:
+ if (unset_environment)
+ assert_se(unsetenv("NOTIFY_SOCKET") == 0);
+
+ return r;
+}
+
+_public_ int sd_notify_barrier(int unset_environment, uint64_t timeout) {
+ _cleanup_close_pair_ int pipe_fd[2] = { -1, -1 };
+ int r;
+
+ if (pipe2(pipe_fd, O_CLOEXEC) < 0)
+ return -errno;
+
+ r = sd_pid_notify_with_fds(0, unset_environment, "BARRIER=1", &pipe_fd[1], 1);
+ if (r <= 0)
+ return r;
+
+ pipe_fd[1] = safe_close(pipe_fd[1]);
+
+ r = fd_wait_for_event(pipe_fd[0], 0 /* POLLHUP is implicit */, timeout);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ETIMEDOUT;
+
+ return 1;
+}
+
+_public_ int sd_pid_notify(pid_t pid, int unset_environment, const char *state) {
+ return sd_pid_notify_with_fds(pid, unset_environment, state, NULL, 0);
+}
+
+_public_ int sd_notify(int unset_environment, const char *state) {
+ return sd_pid_notify_with_fds(0, unset_environment, state, NULL, 0);
+}
+
+_public_ int sd_pid_notifyf(pid_t pid, int unset_environment, const char *format, ...) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ if (format) {
+ va_list ap;
+
+ va_start(ap, format);
+ r = vasprintf(&p, format, ap);
+ va_end(ap);
+
+ if (r < 0 || !p)
+ return -ENOMEM;
+ }
+
+ return sd_pid_notify(pid, unset_environment, p);
+}
+
+_public_ int sd_notifyf(int unset_environment, const char *format, ...) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ if (format) {
+ va_list ap;
+
+ va_start(ap, format);
+ r = vasprintf(&p, format, ap);
+ va_end(ap);
+
+ if (r < 0 || !p)
+ return -ENOMEM;
+ }
+
+ return sd_pid_notify(0, unset_environment, p);
+}
+
+_public_ int sd_booted(void) {
+ /* We test whether the runtime unit file directory has been
+ * created. This takes place in mount-setup.c, so is
+ * guaranteed to happen very early during boot. */
+
+ if (laccess("/run/systemd/system/", F_OK) >= 0)
+ return true;
+
+ if (errno == ENOENT)
+ return false;
+
+ return -errno;
+}
+
+_public_ int sd_watchdog_enabled(int unset_environment, uint64_t *usec) {
+ const char *s, *p = ""; /* p is set to dummy value to do unsetting */
+ uint64_t u;
+ int r = 0;
+
+ s = getenv("WATCHDOG_USEC");
+ if (!s)
+ goto finish;
+
+ r = safe_atou64(s, &u);
+ if (r < 0)
+ goto finish;
+ if (!timestamp_is_set(u)) {
+ r = -EINVAL;
+ goto finish;
+ }
+
+ p = getenv("WATCHDOG_PID");
+ if (p) {
+ pid_t pid;
+
+ r = parse_pid(p, &pid);
+ if (r < 0)
+ goto finish;
+
+ /* Is this for us? */
+ if (getpid_cached() != pid) {
+ r = 0;
+ goto finish;
+ }
+ }
+
+ if (usec)
+ *usec = u;
+
+ r = 1;
+
+finish:
+ if (unset_environment && s)
+ assert_se(unsetenv("WATCHDOG_USEC") == 0);
+ if (unset_environment && p)
+ assert_se(unsetenv("WATCHDOG_PID") == 0);
+
+ return r;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 20:16:36 +0000