src/libsystemd/sd-daemon/sd-daemon.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <limits.h>
   5 #include <mqueue.h>
   6 #include <netinet/in.h>
   7 #include <poll.h>
   8 #include <stdarg.h>
   9 #include <stddef.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <sys/stat.h>
  13 #include <sys/un.h>
  14 #include <unistd.h>
  15
  16 #include "sd-daemon.h"
  17
  18 #include "alloc-util.h"
  19 #include "fd-util.h"
  20 #include "fs-util.h"
  21 #include "io-util.h"
  22 #include "iovec-util.h"
  23 #include "parse-util.h"
  24 #include "path-util.h"
  25 #include "process-util.h"
  26 #include "socket-util.h"
  27 #include "stat-util.h"
  28 #include "strv.h"
  29 #include "time-util.h"
  30
  31 #define SNDBUF_SIZE (8*1024*1024)
  32
  33 static void unsetenv_all(bool unset_environment) {
  34         if (!unset_environment)
  35                 return;
  36
  37         assert_se(unsetenv("LISTEN_PID") == 0);
  38         assert_se(unsetenv("LISTEN_FDS") == 0);
  39         assert_se(unsetenv("LISTEN_FDNAMES") == 0);
  40 }
  41
  42 _public_ int sd_listen_fds(int unset_environment) {
  43         const char *e;
  44         int n, r;
  45         pid_t pid;
  46
  47         e = getenv("LISTEN_PID");
  48         if (!e) {
  49                 r = 0;
  50                 goto finish;
  51         }
  52
  53         r = parse_pid(e, &pid);
  54         if (r < 0)
  55                 goto finish;
  56
  57         /* Is this for us? */
  58         if (getpid_cached() != pid) {
  59                 r = 0;
  60                 goto finish;
  61         }
  62
  63         e = getenv("LISTEN_FDS");
  64         if (!e) {
  65                 r = 0;
  66                 goto finish;
  67         }
  68
  69         r = safe_atoi(e, &n);
  70         if (r < 0)
  71                 goto finish;
  72
  73         assert_cc(SD_LISTEN_FDS_START < INT_MAX);
  74         if (n <= 0 || n > INT_MAX - SD_LISTEN_FDS_START) {
  75                 r = -EINVAL;
  76                 goto finish;
  77         }
  78
  79         for (int fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd ++) {
  80                 r = fd_cloexec(fd, true);
  81                 if (r < 0)
  82                         goto finish;
  83         }
  84
  85         r = n;
  86
  87 finish:
  88         unsetenv_all(unset_environment);
  89         return r;
  90 }
  91
  92 _public_ int sd_listen_fds_with_names(int unset_environment, char ***names) {
  93         _cleanup_strv_free_ char **l = NULL;
  94         bool have_names;
  95         int n_names = 0, n_fds;
  96         const char *e;
  97         int r;
  98
  99         if (!names)
 100                 return sd_listen_fds(unset_environment);
 101
 102         e = getenv("LISTEN_FDNAMES");
 103         if (e) {
 104                 n_names = strv_split_full(&l, e, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
 105                 if (n_names < 0) {
 106                         unsetenv_all(unset_environment);
 107                         return n_names;
 108                 }
 109
 110                 have_names = true;
 111         } else
 112                 have_names = false;
 113
 114         n_fds = sd_listen_fds(unset_environment);
 115         if (n_fds <= 0)
 116                 return n_fds;
 117
 118         if (have_names) {
 119                 if (n_names != n_fds)
 120                         return -EINVAL;
 121         } else {
 122                 r = strv_extend_n(&l, "unknown", n_fds);
 123                 if (r < 0)
 124                         return r;
 125         }
 126
 127         *names = TAKE_PTR(l);
 128
 129         return n_fds;
 130 }
 131
 132 _public_ int sd_is_fifo(int fd, const char *path) {
 133         struct stat st_fd;
 134
 135         assert_return(fd >= 0, -EBADF);
 136
 137         if (fstat(fd, &st_fd) < 0)
 138                 return -errno;
 139
 140         if (!S_ISFIFO(st_fd.st_mode))
 141                 return 0;
 142
 143         if (path) {
 144                 struct stat st_path;
 145
 146                 if (stat(path, &st_path) < 0) {
 147
 148                         if (IN_SET(errno, ENOENT, ENOTDIR))
 149                                 return 0;
 150
 151                         return -errno;
 152                 }
 153
 154                 return stat_inode_same(&st_path, &st_fd);
 155         }
 156
 157         return 1;
 158 }
 159
 160 _public_ int sd_is_special(int fd, const char *path) {
 161         struct stat st_fd;
 162
 163         assert_return(fd >= 0, -EBADF);
 164
 165         if (fstat(fd, &st_fd) < 0)
 166                 return -errno;
 167
 168         if (!S_ISREG(st_fd.st_mode) && !S_ISCHR(st_fd.st_mode))
 169                 return 0;
 170
 171         if (path) {
 172                 struct stat st_path;
 173
 174                 if (stat(path, &st_path) < 0) {
 175
 176                         if (IN_SET(errno, ENOENT, ENOTDIR))
 177                                 return 0;
 178
 179                         return -errno;
 180                 }
 181
 182                 if (S_ISREG(st_fd.st_mode) && S_ISREG(st_path.st_mode))
 183                         return stat_inode_same(&st_path, &st_fd);
 184                 else if (S_ISCHR(st_fd.st_mode) && S_ISCHR(st_path.st_mode))
 185                         return st_path.st_rdev == st_fd.st_rdev;
 186                 else
 187                         return 0;
 188         }
 189
 190         return 1;
 191 }
 192
 193 static int is_socket_internal(int fd, int type, int listening) {
 194         struct stat st_fd;
 195
 196         assert_return(fd >= 0, -EBADF);
 197         assert_return(type >= 0, -EINVAL);
 198
 199         if (fstat(fd, &st_fd) < 0)
 200                 return -errno;
 201
 202         if (!S_ISSOCK(st_fd.st_mode))
 203                 return 0;
 204
 205         if (type != 0) {
 206                 int other_type = 0;
 207                 socklen_t l = sizeof(other_type);
 208
 209                 if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &other_type, &l) < 0)
 210                         return -errno;
 211
 212                 if (l != sizeof(other_type))
 213                         return -EINVAL;
 214
 215                 if (other_type != type)
 216                         return 0;
 217         }
 218
 219         if (listening >= 0) {
 220                 int accepting = 0;
 221                 socklen_t l = sizeof(accepting);
 222
 223                 if (getsockopt(fd, SOL_SOCKET, SO_ACCEPTCONN, &accepting, &l) < 0)
 224                         return -errno;
 225
 226                 if (l != sizeof(accepting))
 227                         return -EINVAL;
 228
 229                 if (!accepting != !listening)
 230                         return 0;
 231         }
 232
 233         return 1;
 234 }
 235
 236 _public_ int sd_is_socket(int fd, int family, int type, int listening) {
 237         int r;
 238
 239         assert_return(fd >= 0, -EBADF);
 240         assert_return(family >= 0, -EINVAL);
 241
 242         r = is_socket_internal(fd, type, listening);
 243         if (r <= 0)
 244                 return r;
 245
 246         if (family > 0) {
 247                 union sockaddr_union sockaddr = {};
 248                 socklen_t l = sizeof(sockaddr);
 249
 250                 if (getsockname(fd, &sockaddr.sa, &l) < 0)
 251                         return -errno;
 252
 253                 if (l < sizeof(sa_family_t))
 254                         return -EINVAL;
 255
 256                 return sockaddr.sa.sa_family == family;
 257         }
 258
 259         return 1;
 260 }
 261
 262 _public_ int sd_is_socket_inet(int fd, int family, int type, int listening, uint16_t port) {
 263         union sockaddr_union sockaddr = {};
 264         socklen_t l = sizeof(sockaddr);
 265         int r;
 266
 267         assert_return(fd >= 0, -EBADF);
 268         assert_return(IN_SET(family, 0, AF_INET, AF_INET6), -EINVAL);
 269
 270         r = is_socket_internal(fd, type, listening);
 271         if (r <= 0)
 272                 return r;
 273
 274         if (getsockname(fd, &sockaddr.sa, &l) < 0)
 275                 return -errno;
 276
 277         if (l < sizeof(sa_family_t))
 278                 return -EINVAL;
 279
 280         if (!IN_SET(sockaddr.sa.sa_family, AF_INET, AF_INET6))
 281                 return 0;
 282
 283         if (family != 0)
 284                 if (sockaddr.sa.sa_family != family)
 285                         return 0;
 286
 287         if (port > 0) {
 288                 unsigned sa_port;
 289
 290                 r = sockaddr_port(&sockaddr.sa, &sa_port);
 291                 if (r < 0)
 292                         return r;
 293
 294                 return port == sa_port;
 295         }
 296
 297         return 1;
 298 }
 299
 300 _public_ int sd_is_socket_sockaddr(int fd, int type, const struct sockaddr* addr, unsigned addr_len, int listening) {
 301         union sockaddr_union sockaddr = {};
 302         socklen_t l = sizeof(sockaddr);
 303         int r;
 304
 305         assert_return(fd >= 0, -EBADF);
 306         assert_return(addr, -EINVAL);
 307         assert_return(addr_len >= sizeof(sa_family_t), -ENOBUFS);
 308         assert_return(IN_SET(addr->sa_family, AF_INET, AF_INET6), -EPFNOSUPPORT);
 309
 310         r = is_socket_internal(fd, type, listening);
 311         if (r <= 0)
 312                 return r;
 313
 314         if (getsockname(fd, &sockaddr.sa, &l) < 0)
 315                 return -errno;
 316
 317         if (l < sizeof(sa_family_t))
 318                 return -EINVAL;
 319
 320         if (sockaddr.sa.sa_family != addr->sa_family)
 321                 return 0;
 322
 323         if (sockaddr.sa.sa_family == AF_INET) {
 324                 const struct sockaddr_in *in = (const struct sockaddr_in *) addr;
 325
 326                 if (l < sizeof(struct sockaddr_in) || addr_len < sizeof(struct sockaddr_in))
 327                         return -EINVAL;
 328
 329                 if (in->sin_port != 0 &&
 330                     sockaddr.in.sin_port != in->sin_port)
 331                         return false;
 332
 333                 return sockaddr.in.sin_addr.s_addr == in->sin_addr.s_addr;
 334
 335         } else {
 336                 const struct sockaddr_in6 *in = (const struct sockaddr_in6 *) addr;
 337
 338                 if (l < sizeof(struct sockaddr_in6) || addr_len < sizeof(struct sockaddr_in6))
 339                         return -EINVAL;
 340
 341                 if (in->sin6_port != 0 &&
 342                     sockaddr.in6.sin6_port != in->sin6_port)
 343                         return false;
 344
 345                 if (in->sin6_flowinfo != 0 &&
 346                     sockaddr.in6.sin6_flowinfo != in->sin6_flowinfo)
 347                         return false;
 348
 349                 if (in->sin6_scope_id != 0 &&
 350                     sockaddr.in6.sin6_scope_id != in->sin6_scope_id)
 351                         return false;
 352
 353                 return memcmp(sockaddr.in6.sin6_addr.s6_addr, in->sin6_addr.s6_addr,
 354                               sizeof(in->sin6_addr.s6_addr)) == 0;
 355         }
 356 }
 357
 358 _public_ int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length) {
 359         union sockaddr_union sockaddr = {};
 360         socklen_t l = sizeof(sockaddr);
 361         int r;
 362
 363         assert_return(fd >= 0, -EBADF);
 364
 365         r = is_socket_internal(fd, type, listening);
 366         if (r <= 0)
 367                 return r;
 368
 369         if (getsockname(fd, &sockaddr.sa, &l) < 0)
 370                 return -errno;
 371
 372         if (l < sizeof(sa_family_t))
 373                 return -EINVAL;
 374
 375         if (sockaddr.sa.sa_family != AF_UNIX)
 376                 return 0;
 377
 378         if (path) {
 379                 if (length == 0)
 380                         length = strlen(path);
 381
 382                 if (length == 0)
 383                         /* Unnamed socket */
 384                         return l == offsetof(struct sockaddr_un, sun_path);
 385
 386                 if (path[0])
 387                         /* Normal path socket */
 388                         return
 389                                 (l >= offsetof(struct sockaddr_un, sun_path) + length + 1) &&
 390                                 memcmp(path, sockaddr.un.sun_path, length+1) == 0;
 391                 else
 392                         /* Abstract namespace socket */
 393                         return
 394                                 (l == offsetof(struct sockaddr_un, sun_path) + length) &&
 395                                 memcmp(path, sockaddr.un.sun_path, length) == 0;
 396         }
 397
 398         return 1;
 399 }
 400
 401 _public_ int sd_is_mq(int fd, const char *path) {
 402         struct mq_attr attr;
 403
 404         /* Check that the fd is valid */
 405         assert_return(fcntl(fd, F_GETFD) >= 0, -errno);
 406
 407         if (mq_getattr(fd, &attr) < 0) {
 408                 if (errno == EBADF)
 409                         /* A non-mq fd (or an invalid one, but we ruled that out above) */
 410                         return 0;
 411                 return -errno;
 412         }
 413
 414         if (path) {
 415                 _cleanup_free_ char *fpath = NULL;
 416                 struct stat a, b;
 417
 418                 assert_return(path_is_absolute(path), -EINVAL);
 419
 420                 if (fstat(fd, &a) < 0)
 421                         return -errno;
 422
 423                 fpath = path_join("/dev/mqueue", path);
 424                 if (!fpath)
 425                         return -ENOMEM;
 426
 427                 if (stat(fpath, &b) < 0)
 428                         return -errno;
 429
 430                 if (!stat_inode_same(&a, &b))
 431                         return 0;
 432         }
 433
 434         return 1;
 435 }
 436
 437 static int vsock_bind_privileged_port(int fd) {
 438         union sockaddr_union sa = {
 439                 .vm.svm_family = AF_VSOCK,
 440                 .vm.svm_cid = VMADDR_CID_ANY,
 441                 .vm.svm_port = 1023,
 442         };
 443         int r;
 444
 445         assert(fd >= 0);
 446
 447         do
 448                 r = RET_NERRNO(bind(fd, &sa.sa, sizeof(sa.vm)));
 449         while (r == -EADDRINUSE && --sa.vm.svm_port > 0);
 450
 451         return r;
 452 }
 453
 454 static int pid_notify_with_fds_internal(
 455                 pid_t pid,
 456                 const char *state,
 457                 const int *fds,
 458                 unsigned n_fds) {
 459         SocketAddress address;
 460         struct iovec iovec;
 461         struct msghdr msghdr = {
 462                 .msg_iov = &iovec,
 463                 .msg_iovlen = 1,
 464                 .msg_name = &address.sockaddr,
 465         };
 466         _cleanup_close_ int fd = -EBADF;
 467         struct cmsghdr *cmsg = NULL;
 468         const char *e;
 469         bool send_ucred;
 470         ssize_t n;
 471         int type, r;
 472
 473         if (!state)
 474                 return -EINVAL;
 475
 476         if (n_fds > 0 && !fds)
 477                 return -EINVAL;
 478
 479         e = getenv("NOTIFY_SOCKET");
 480         if (!e)
 481                 return 0;
 482
 483         /* Allow AF_UNIX and AF_VSOCK, reject the rest. */
 484         r = socket_address_parse_unix(&address, e);
 485         if (r == -EPROTO)
 486                 r = socket_address_parse_vsock(&address, e);
 487         if (r < 0)
 488                 return r;
 489         msghdr.msg_namelen = address.size;
 490
 491         /* If we didn't get an address (which is a normal pattern when specifying VSOCK tuples) error out,
 492          * we always require a specific CID. */
 493         if (address.sockaddr.vm.svm_family == AF_VSOCK && address.sockaddr.vm.svm_cid == VMADDR_CID_ANY)
 494                 return -EINVAL;
 495
 496         type = address.type == 0 ? SOCK_DGRAM : address.type;
 497
 498         /* At the time of writing QEMU does not yet support AF_VSOCK + SOCK_DGRAM and returns
 499          * ENODEV. Fallback to SOCK_SEQPACKET in that case. */
 500         fd = socket(address.sockaddr.sa.sa_family, type|SOCK_CLOEXEC, 0);
 501         if (fd < 0) {
 502                 if (!(ERRNO_IS_NOT_SUPPORTED(errno) || errno == ENODEV) || address.sockaddr.sa.sa_family != AF_VSOCK || address.type > 0)
 503                         return log_debug_errno(errno, "Failed to open %s notify socket to '%s': %m", socket_address_type_to_string(type), e);
 504
 505                 type = SOCK_SEQPACKET;
 506                 fd = socket(address.sockaddr.sa.sa_family, type|SOCK_CLOEXEC, 0);
 507                 if (fd < 0 && ERRNO_IS_NOT_SUPPORTED(errno)) {
 508                         type = SOCK_STREAM;
 509                         fd = socket(address.sockaddr.sa.sa_family, type|SOCK_CLOEXEC, 0);
 510                 }
 511                 if (fd < 0)
 512                         return log_debug_errno(errno, "Failed to open %s socket to '%s': %m", socket_address_type_to_string(type), e);
 513         }
 514
 515         if (address.sockaddr.sa.sa_family == AF_VSOCK) {
 516                 r = vsock_bind_privileged_port(fd);
 517                 if (r < 0 && !ERRNO_IS_PRIVILEGE(r))
 518                         return log_debug_errno(r, "Failed to bind socket to privileged port: %m");
 519         }
 520
 521         if (IN_SET(type, SOCK_STREAM, SOCK_SEQPACKET)) {
 522                 if (connect(fd, &address.sockaddr.sa, address.size) < 0)
 523                         return log_debug_errno(errno, "Failed to connect socket to '%s': %m", e);
 524
 525                 msghdr.msg_name = NULL;
 526                 msghdr.msg_namelen = 0;
 527         }
 528
 529         (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
 530
 531         iovec = IOVEC_MAKE_STRING(state);
 532
 533         send_ucred =
 534                 (pid != 0 && pid != getpid_cached()) ||
 535                 getuid() != geteuid() ||
 536                 getgid() != getegid();
 537
 538         if (n_fds > 0 || send_ucred) {
 539                 /* CMSG_SPACE(0) may return value different than zero, which results in miscalculated controllen. */
 540                 msghdr.msg_controllen =
 541                         (n_fds > 0 ? CMSG_SPACE(sizeof(int) * n_fds) : 0) +
 542                         (send_ucred ? CMSG_SPACE(sizeof(struct ucred)) : 0);
 543
 544                 msghdr.msg_control = alloca0(msghdr.msg_controllen);
 545
 546                 cmsg = CMSG_FIRSTHDR(&msghdr);
 547                 if (n_fds > 0) {
 548                         cmsg->cmsg_level = SOL_SOCKET;
 549                         cmsg->cmsg_type = SCM_RIGHTS;
 550                         cmsg->cmsg_len = CMSG_LEN(sizeof(int) * n_fds);
 551
 552                         memcpy(CMSG_DATA(cmsg), fds, sizeof(int) * n_fds);
 553
 554                         if (send_ucred)
 555                                 assert_se(cmsg = CMSG_NXTHDR(&msghdr, cmsg));
 556                 }
 557
 558                 if (send_ucred) {
 559                         struct ucred *ucred;
 560
 561                         cmsg->cmsg_level = SOL_SOCKET;
 562                         cmsg->cmsg_type = SCM_CREDENTIALS;
 563                         cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
 564
 565                         ucred = CMSG_TYPED_DATA(cmsg, struct ucred);
 566                         ucred->pid = pid != 0 ? pid : getpid_cached();
 567                         ucred->uid = getuid();
 568                         ucred->gid = getgid();
 569                 }
 570         }
 571
 572         do {
 573                 /* First try with fake ucred data, as requested */
 574                 n = sendmsg(fd, &msghdr, MSG_NOSIGNAL);
 575                 if (n < 0) {
 576                         if (!send_ucred)
 577                                 return log_debug_errno(errno, "Failed to send notify message to '%s': %m", e);
 578
 579                         /* If that failed, try with our own ucred instead */
 580                         msghdr.msg_controllen -= CMSG_SPACE(sizeof(struct ucred));
 581                         if (msghdr.msg_controllen == 0)
 582                                 msghdr.msg_control = NULL;
 583
 584                         n = 0;
 585                         send_ucred = false;
 586                 } else {
 587                         /* Unless we're using SOCK_STREAM, we expect to write all the contents immediately. */
 588                         if (type != SOCK_STREAM && (size_t) n < iovec_total_size(msghdr.msg_iov, msghdr.msg_iovlen))
 589                                 return -EIO;
 590
 591                         /* Make sure we only send fds and ucred once, even if we're using SOCK_STREAM. */
 592                         msghdr.msg_control = NULL;
 593                         msghdr.msg_controllen = 0;
 594                 }
 595         } while (!iovec_increment(msghdr.msg_iov, msghdr.msg_iovlen, n));
 596
 597         return 1;
 598 }
 599
 600 _public_ int sd_pid_notify_with_fds(
 601                 pid_t pid,
 602                 int unset_environment,
 603                 const char *state,
 604                 const int *fds,
 605                 unsigned n_fds) {
 606
 607         int r;
 608
 609         r = pid_notify_with_fds_internal(pid, state, fds, n_fds);
 610
 611         if (unset_environment)
 612                 assert_se(unsetenv("NOTIFY_SOCKET") == 0);
 613
 614         return r;
 615 }
 616
 617 _public_ int sd_pid_notify_barrier(pid_t pid, int unset_environment, uint64_t timeout) {
 618         _cleanup_close_pair_ int pipe_fd[2] = EBADF_PAIR;
 619         int r;
 620
 621         if (pipe2(pipe_fd, O_CLOEXEC) < 0)
 622                 return -errno;
 623
 624         r = sd_pid_notify_with_fds(pid, unset_environment, "BARRIER=1", &pipe_fd[1], 1);
 625         if (r <= 0)
 626                 return r;
 627
 628         pipe_fd[1] = safe_close(pipe_fd[1]);
 629
 630         r = fd_wait_for_event(pipe_fd[0], 0 /* POLLHUP is implicit */, timeout);
 631         if (r < 0)
 632                 return r;
 633         if (r == 0)
 634                 return -ETIMEDOUT;
 635
 636         return 1;
 637 }
 638
 639 _public_ int sd_notify_barrier(int unset_environment, uint64_t timeout) {
 640         return sd_pid_notify_barrier(0, unset_environment, timeout);
 641 }
 642
 643 _public_ int sd_pid_notify(pid_t pid, int unset_environment, const char *state) {
 644         return sd_pid_notify_with_fds(pid, unset_environment, state, NULL, 0);
 645 }
 646
 647 _public_ int sd_notify(int unset_environment, const char *state) {
 648         return sd_pid_notify_with_fds(0, unset_environment, state, NULL, 0);
 649 }
 650
 651 _public_ int sd_pid_notifyf(pid_t pid, int unset_environment, const char *format, ...) {
 652         _cleanup_free_ char *p = NULL;
 653         int r;
 654
 655         if (format) {
 656                 va_list ap;
 657
 658                 va_start(ap, format);
 659                 r = vasprintf(&p, format, ap);
 660                 va_end(ap);
 661
 662                 if (r < 0 || !p)
 663                         return -ENOMEM;
 664         }
 665
 666         return sd_pid_notify(pid, unset_environment, p);
 667 }
 668
 669 _public_ int sd_notifyf(int unset_environment, const char *format, ...) {
 670         _cleanup_free_ char *p = NULL;
 671         int r;
 672
 673         if (format) {
 674                 va_list ap;
 675
 676                 va_start(ap, format);
 677                 r = vasprintf(&p, format, ap);
 678                 va_end(ap);
 679
 680                 if (r < 0 || !p)
 681                         return -ENOMEM;
 682         }
 683
 684         return sd_pid_notify(0, unset_environment, p);
 685 }
 686
 687 _public_ int sd_pid_notifyf_with_fds(
 688                 pid_t pid,
 689                 int unset_environment,
 690                 const int *fds, size_t n_fds,
 691                 const char *format, ...) {
 692
 693         _cleanup_free_ char *p = NULL;
 694         int r;
 695
 696         /* Paranoia check: we traditionally used 'unsigned' as array size, but we nowadays more correctly use
 697          * 'size_t'. sd_pid_notifyf_with_fds() and sd_pid_notify_with_fds() are from different eras, hence
 698          * differ in this. Let's catch resulting incompatibilites early, even though they are pretty much
 699          * theoretic only */
 700         if (n_fds > UINT_MAX)
 701                 return -E2BIG;
 702
 703         if (format) {
 704                 va_list ap;
 705
 706                 va_start(ap, format);
 707                 r = vasprintf(&p, format, ap);
 708                 va_end(ap);
 709
 710                 if (r < 0 || !p)
 711                         return -ENOMEM;
 712         }
 713
 714         return sd_pid_notify_with_fds(pid, unset_environment, p, fds, n_fds);
 715 }
 716
 717 _public_ int sd_booted(void) {
 718         /* We test whether the runtime unit file directory has been
 719          * created. This takes place in mount-setup.c, so is
 720          * guaranteed to happen very early during boot. */
 721
 722         if (laccess("/run/systemd/system/", F_OK) >= 0)
 723                 return true;
 724
 725         if (errno == ENOENT)
 726                 return false;
 727
 728         return -errno;
 729 }
 730
 731 _public_ int sd_watchdog_enabled(int unset_environment, uint64_t *usec) {
 732         const char *s, *p = ""; /* p is set to dummy value to do unsetting */
 733         uint64_t u;
 734         int r = 0;
 735
 736         s = getenv("WATCHDOG_USEC");
 737         if (!s)
 738                 goto finish;
 739
 740         r = safe_atou64(s, &u);
 741         if (r < 0)
 742                 goto finish;
 743         if (!timestamp_is_set(u)) {
 744                 r = -EINVAL;
 745                 goto finish;
 746         }
 747
 748         p = getenv("WATCHDOG_PID");
 749         if (p) {
 750                 pid_t pid;
 751
 752                 r = parse_pid(p, &pid);
 753                 if (r < 0)
 754                         goto finish;
 755
 756                 /* Is this for us? */
 757                 if (getpid_cached() != pid) {
 758                         r = 0;
 759                         goto finish;
 760                 }
 761         }
 762
 763         if (usec)
 764                 *usec = u;
 765
 766         r = 1;
 767
 768 finish:
 769         if (unset_environment && s)
 770                 assert_se(unsetenv("WATCHDOG_USEC") == 0);
 771         if (unset_environment && p)
 772                 assert_se(unsetenv("WATCHDOG_PID") == 0);
 773
 774         return r;
 775 }