- for (;;) {
- struct ucred *ucred = NULL;
- struct timeval *tv = NULL;
- struct cmsghdr *cmsg;
- char *label = NULL;
- size_t label_len = 0;
-
- struct iovec iovec;
- union {
- struct cmsghdr cmsghdr;
-
- /* We use NAME_MAX space for the
- * SELinux label here. The kernel
- * currently enforces no limit, but
- * according to suggestions from the
- * SELinux people this will change and
- * it will probably be identical to
- * NAME_MAX. For now we use that, but
- * this should be updated one day when
- * the final limit is known.*/
- uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
- CMSG_SPACE(sizeof(struct timeval)) +
- CMSG_SPACE(sizeof(int)) + /* fd */
- CMSG_SPACE(NAME_MAX)]; /* selinux label */
- } control = {};
- struct msghdr msghdr = {
- .msg_iov = &iovec,
- .msg_iovlen = 1,
- .msg_control = &control,
- .msg_controllen = sizeof(control),
- };
-
- ssize_t n;
- int v;
- int *fds = NULL;
- unsigned n_fds = 0;
-
- if (ioctl(ev->data.fd, SIOCINQ, &v) < 0) {
- log_error("SIOCINQ failed: %m");
- return -errno;
- }
-
- if (!GREEDY_REALLOC(s->buffer, s->buffer_size, LINE_MAX + (size_t) v))
- return log_oom();
-
- iovec.iov_base = s->buffer;
- iovec.iov_len = s->buffer_size;
-
- n = recvmsg(ev->data.fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
- if (n < 0) {
- if (errno == EINTR || errno == EAGAIN)
- return 1;
-
- log_error("recvmsg() failed: %m");
- return -errno;
- }
-
- for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
-
- if (cmsg->cmsg_level == SOL_SOCKET &&
- cmsg->cmsg_type == SCM_CREDENTIALS &&
- cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred)))
- ucred = (struct ucred*) CMSG_DATA(cmsg);
- else if (cmsg->cmsg_level == SOL_SOCKET &&
- cmsg->cmsg_type == SCM_SECURITY) {
- label = (char*) CMSG_DATA(cmsg);
- label_len = cmsg->cmsg_len - CMSG_LEN(0);
- } else if (cmsg->cmsg_level == SOL_SOCKET &&
- cmsg->cmsg_type == SO_TIMESTAMP &&
- cmsg->cmsg_len == CMSG_LEN(sizeof(struct timeval)))
- tv = (struct timeval*) CMSG_DATA(cmsg);
- else if (cmsg->cmsg_level == SOL_SOCKET &&
- cmsg->cmsg_type == SCM_RIGHTS) {
- fds = (int*) CMSG_DATA(cmsg);
- n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
- }
- }