-static void iovec_advance(struct iovec *iov, unsigned *idx, size_t size) {
-
- while (size > 0) {
- struct iovec *i = iov + *idx;
-
- if (i->iov_len > size) {
- i->iov_base = (uint8_t*) i->iov_base + size;
- i->iov_len -= size;
- return;
- }
-
- size -= i->iov_len;
-
- i->iov_base = NULL;
- i->iov_len = 0;
-
- (*idx) ++;
- }
-}
-
-static int bus_write_auth(sd_bus *b) {
- struct msghdr mh;
- ssize_t k;
-
- assert(b);
- assert(b->state == BUS_AUTHENTICATING);
-
- if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
- return 0;
-
- if (b->auth_timeout == 0)
- b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
-
- zero(mh);
- mh.msg_iov = b->auth_iovec + b->auth_index;
- mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
-
- k = sendmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
- if (k < 0)
- return errno == EAGAIN ? 0 : -errno;
-
- iovec_advance(b->auth_iovec, &b->auth_index, (size_t) k);
-
- return 1;
-}
-
-static int bus_auth_verify(sd_bus *b) {
- char *e, *f, *start;
- sd_id128_t peer;
- unsigned i;
- int r;
-
- /* We expect two response lines: "OK" and possibly
- * "AGREE_UNIX_FD" */
-
- e = memmem(b->rbuffer, b->rbuffer_size, "\r\n", 2);
- if (!e)
- return 0;
-
- if (b->negotiate_fds) {
- f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2);
- if (!f)
- return 0;
-
- start = f + 2;
- } else {
- f = NULL;
- start = e + 2;
- }
-
- /* Nice! We got all the lines we need. First check the OK
- * line */
-
- if (e - (char*) b->rbuffer != 3 + 32)
- return -EPERM;
-
- if (memcmp(b->rbuffer, "OK ", 3))
- return -EPERM;
-
- for (i = 0; i < 32; i += 2) {
- int x, y;
-
- x = unhexchar(((char*) b->rbuffer)[3 + i]);
- y = unhexchar(((char*) b->rbuffer)[3 + i + 1]);
-
- if (x < 0 || y < 0)
- return -EINVAL;
-
- peer.bytes[i/2] = ((uint8_t) x << 4 | (uint8_t) y);
- }
-
- if (!sd_id128_equal(b->peer, SD_ID128_NULL) &&
- !sd_id128_equal(b->peer, peer))
- return -EPERM;
-
- b->peer = peer;
-
- /* And possibly check the second line, too */
-
- if (f)
- b->can_fds =
- (f - e == sizeof("\r\nAGREE_UNIX_FD") - 1) &&
- memcmp(e + 2, "AGREE_UNIX_FD", sizeof("AGREE_UNIX_FD") - 1) == 0;
-
- b->rbuffer_size -= (start - (char*) b->rbuffer);
- memmove(b->rbuffer, start, b->rbuffer_size);
-
- r = bus_start_running(b);
- if (r < 0)
- return r;
-
- return 1;
-}
-
-static int bus_read_auth(sd_bus *b) {
- struct msghdr mh;
- struct iovec iov;
- size_t n;
- ssize_t k;
- int r;
- void *p;
-
- assert(b);
-
- r = bus_auth_verify(b);
- if (r != 0)
- return r;
-
- n = MAX(3 + 32 + 2 + sizeof("AGREE_UNIX_FD") - 1 + 2, b->rbuffer_size * 2);
-
- if (n > BUS_AUTH_SIZE_MAX)
- n = BUS_AUTH_SIZE_MAX;
-
- if (b->rbuffer_size >= n)
- return -ENOBUFS;
-
- p = realloc(b->rbuffer, n);
- if (!p)
- return -ENOMEM;
-
- b->rbuffer = p;
-
- zero(iov);
- iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
- iov.iov_len = n - b->rbuffer_size;
-
- zero(mh);
- mh.msg_iov = &iov;
- mh.msg_iovlen = 1;
-
- k = recvmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
- if (k < 0)
- return errno == EAGAIN ? 0 : -errno;
- if (k == 0)
- return -ECONNRESET;
-
- b->rbuffer_size += k;
-
- r = bus_auth_verify(b);
- if (r != 0)
- return r;
-
- return 1;
-}
-
-static int bus_setup_fd(sd_bus *b) {
- int one;
-
- assert(b);
-
- /* Enable SO_PASSCRED + SO_PASSEC. We try this on any socket,
- * just in case. This is actually irrelavant for */
- one = 1;
- setsockopt(b->fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
- setsockopt(b->fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one));
-
- /* Increase the buffers to a MB */
- fd_inc_rcvbuf(b->fd, 1024*1024);
- fd_inc_sndbuf(b->fd, 1024*1024);
-
- return 0;
-}
-
-static int bus_start_auth(sd_bus *b) {
- static const char auth_prefix[] = "\0AUTH EXTERNAL ";
- static const char auth_suffix_with_unix_fd[] = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
- static const char auth_suffix_without_unix_fd[] = "\r\nBEGIN\r\n";
-
- char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
- size_t l;
- const char *auth_suffix;
- int domain = 0, r;
- socklen_t sl;
-
- assert(b);
-
- b->state = BUS_AUTHENTICATING;
-
- sl = sizeof(domain);
- r = getsockopt(b->fd, SOL_SOCKET, SO_DOMAIN, &domain, &sl);
- if (r < 0)
- return -errno;
-
- if (domain != AF_UNIX)
- b->negotiate_fds = false;
-
- snprintf(text, sizeof(text), "%llu", (unsigned long long) geteuid());
- char_array_0(text);
-
- l = strlen(text);
- b->auth_uid = hexmem(text, l);
- if (!b->auth_uid)
- return -ENOMEM;
-
- auth_suffix = b->negotiate_fds ? auth_suffix_with_unix_fd : auth_suffix_without_unix_fd;
-
- b->auth_iovec[0].iov_base = (void*) auth_prefix;
- b->auth_iovec[0].iov_len = sizeof(auth_prefix) -1;
- b->auth_iovec[1].iov_base = (void*) b->auth_uid;
- b->auth_iovec[1].iov_len = l * 2;
- b->auth_iovec[2].iov_base = (void*) auth_suffix;
- b->auth_iovec[2].iov_len = strlen(auth_suffix);
- b->auth_size = sizeof(auth_prefix) - 1 + l * 2 + sizeof(auth_suffix) - 1;
-
- return bus_write_auth(b);
-}
-
-static int bus_connect(sd_bus *b) {
- int r;
-
- assert(b);
- assert(b->fd < 0);
- assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
-
- b->fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
- if (b->fd < 0)
- return -errno;
-
- r = bus_setup_fd(b);
- if (r < 0)
- return r;
-
- r = connect(b->fd, &b->sockaddr.sa, b->sockaddr_size);
- if (r < 0) {
- if (errno == EINPROGRESS)
- return 1;
-
- return -errno;
- }
-
- return bus_start_auth(b);
-}
-
-static int bus_exec(sd_bus *b) {
- int s[2];
- pid_t pid;
-
- assert(b);
- assert(b->fd < 0);
- assert(b->exec_path);
-
- b->fd = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
- if (b->fd < 0)
- return -errno;
-
- pid = fork();
- if (pid < 0) {
- close_pipe(s);
- return -errno;
- }
- if (pid == 0) {
- /* Child */
-
- close_all_fds(s, 2);
- close_nointr_nofail(s[0]);
-
- assert_se(dup3(s[1], STDIN_FILENO, 0) == STDIN_FILENO);
- assert_se(dup3(s[1], STDOUT_FILENO, 0) == STDOUT_FILENO);
-
- if (s[1] != STDIN_FILENO && s[1] != STDOUT_FILENO)
- close_nointr_nofail(s[1]);
-
- fd_cloexec(STDIN_FILENO, false);
- fd_cloexec(STDOUT_FILENO, false);
- fd_nonblock(STDIN_FILENO, false);
- fd_nonblock(STDOUT_FILENO, false);
-
- if (b->exec_argv)
- execvp(b->exec_path, b->exec_argv);
- else {
- const char *argv[] = { b->exec_path, NULL };
- execvp(b->exec_path, (char**) argv);
- }
-
- _exit(EXIT_FAILURE);
- }
-
- close_nointr_nofail(s[1]);
- b->fd = s[0];
-
- return bus_start_auth(b);
-}
-
-static int bus_start_connect(sd_bus *b) {