+ static struct udevsend_msg usend_msg;
+ struct hotplug_msg *msg;
+ int bufpos;
+ int i;
+ ssize_t size;
+ struct msghdr smsg;
+ struct cmsghdr *cmsg;
+ struct iovec iov;
+ struct ucred *cred;
+ char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ int envbuf_size;
+
+ memset(&usend_msg, 0x00, sizeof(struct udevsend_msg));
+ iov.iov_base = &usend_msg;
+ iov.iov_len = sizeof(struct udevsend_msg);
+
+ memset(&smsg, 0x00, sizeof(struct msghdr));
+ smsg.msg_iov = &iov;
+ smsg.msg_iovlen = 1;
+ smsg.msg_control = cred_msg;
+ smsg.msg_controllen = sizeof(cred_msg);
+
+ size = recvmsg(sock, &smsg, 0);
+ if (size < 0) {
+ if (errno != EINTR)
+ dbg("unable to receive message");
+ return;
+ }
+ cmsg = CMSG_FIRSTHDR(&smsg);
+ cred = (struct ucred *) CMSG_DATA(cmsg);
+
+ if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+ dbg("no sender credentials received, message ignored");
+ goto exit;
+ }
+
+ if (cred->uid != 0) {
+ dbg("sender uid=%i, message ignored", cred->uid);
+ goto exit;
+ }
+
+ if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
+ dbg("message magic '%s' doesn't match, ignore it", usend_msg.magic);
+ goto exit;
+ }
+
+ envbuf_size = size - offsetof(struct udevsend_msg, envbuf);
+ dbg("envbuf_size=%i", envbuf_size);
+ msg = malloc(sizeof(struct hotplug_msg) + envbuf_size);
+ memset(msg, 0x00, sizeof(struct hotplug_msg) + envbuf_size);
+
+ /* copy environment buffer and reconstruct envp */
+ memcpy(msg->envbuf, usend_msg.envbuf, envbuf_size);
+ bufpos = 0;
+ for (i = 0; (bufpos < envbuf_size) && (i < HOTPLUG_NUM_ENVP-2); i++) {
+ int keylen;
+ char *key;
+
+ key = &msg->envbuf[bufpos];
+ keylen = strlen(key);
+ msg->envp[i] = key;
+ bufpos += keylen + 1;
+ dbg("add '%s' to msg.envp[%i]", msg->envp[i], i);
+
+ /* remember some keys for further processing */
+ if (strncmp(key, "ACTION=", 7) == 0)
+ msg->action = &key[7];
+
+ if (strncmp(key, "DEVPATH=", 8) == 0)
+ msg->devpath = &key[8];
+
+ if (strncmp(key, "SUBSYSTEM=", 10) == 0)
+ msg->subsystem = &key[10];
+
+ if (strncmp(key, "SEQNUM=", 7) == 0)
+ msg->seqnum = strtoull(&key[7], NULL, 10);
+
+ if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
+ msg->physdevpath = &key[12];
+ }
+ msg->envp[i++] = "UDEVD_EVENT=1";
+ msg->envp[i] = NULL;
+
+ /* if no seqnum is given, we move straight to exec queue */
+ if (msg->seqnum == 0) {
+ list_add(&msg->list, &exec_list);
+ run_exec_q = 1;
+ } else {
+ msg_queue_insert(msg);
+ }
+
+exit:
+ return;