#include "libudev.h"
#include "alloc-util.h"
+#include "device-private.h"
+#include "device-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "format-util.h"
return 0;
}
-/**
- * udev_monitor_receive_device:
- * @udev_monitor: udev monitor
- *
- * Receive data from the udev monitor socket, allocate a new udev
- * device, fill in the received data, and return the device.
- *
- * Only socket connections with uid=0 are accepted.
- *
- * The monitor socket is by default set to NONBLOCK. A variant of poll() on
- * the file descriptor returned by udev_monitor_get_fd() should to be used to
- * wake up when new devices arrive, or alternatively the file descriptor
- * switched into blocking mode.
- *
- * The initial refcount is 1, and needs to be decremented to
- * release the resources of the udev device.
- *
- * Returns: a new udev device, or #NULL, in case of an error
- **/
-_public_ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monitor)
-{
- struct udev_device *udev_device;
- struct msghdr smsg;
- struct iovec iov;
- char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
- struct cmsghdr *cmsg;
- union sockaddr_union snl;
- struct ucred *cred;
+static int udev_monitor_receive_device_one(struct udev_monitor *udev_monitor, sd_device **ret) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
union {
struct udev_monitor_netlink_header nlh;
char raw[8192];
} buf;
- ssize_t buflen;
- ssize_t bufpos;
+ struct iovec iov = {
+ .iov_base = &buf,
+ .iov_len = sizeof(buf)
+ };
+ char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ union sockaddr_union snl;
+ struct msghdr smsg = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_control = cred_msg,
+ .msg_controllen = sizeof(cred_msg),
+ .msg_name = &snl,
+ .msg_namelen = sizeof(snl),
+ };
+ struct cmsghdr *cmsg;
+ struct ucred *cred;
+ ssize_t buflen, bufpos;
bool is_initialized = false;
+ int r;
-retry:
- if (udev_monitor == NULL) {
- errno = EINVAL;
- return NULL;
- }
- iov.iov_base = &buf;
- iov.iov_len = sizeof(buf);
- memzero(&smsg, sizeof(struct msghdr));
- smsg.msg_iov = &iov;
- smsg.msg_iovlen = 1;
- smsg.msg_control = cred_msg;
- smsg.msg_controllen = sizeof(cred_msg);
- smsg.msg_name = &snl;
- smsg.msg_namelen = sizeof(snl);
+ assert(ret);
buflen = recvmsg(udev_monitor->sock, &smsg, 0);
if (buflen < 0) {
if (errno != EINTR)
- log_debug("unable to receive message");
- return NULL;
+ log_debug_errno(errno, "Failed to receive message: %m");
+ return -errno;
}
- if (buflen < 32 || (smsg.msg_flags & MSG_TRUNC)) {
- log_debug("invalid message length");
- errno = EINVAL;
- return NULL;
- }
+ if (buflen < 32 || (smsg.msg_flags & MSG_TRUNC))
+ return log_debug_errno(EINVAL, "Invalid message length.");
- if (snl.nl.nl_groups == 0) {
+ if (snl.nl.nl_groups == UDEV_MONITOR_NONE) {
/* unicast message, check if we trust the sender */
if (udev_monitor->snl_trusted_sender.nl.nl_pid == 0 ||
- snl.nl.nl_pid != udev_monitor->snl_trusted_sender.nl.nl_pid) {
- log_debug("unicast netlink message ignored");
- errno = EAGAIN;
- return NULL;
- }
+ snl.nl.nl_pid != udev_monitor->snl_trusted_sender.nl.nl_pid)
+ return log_debug_errno(EAGAIN, "Unicast netlink message ignored.");
+
} else if (snl.nl.nl_groups == UDEV_MONITOR_KERNEL) {
- if (snl.nl.nl_pid > 0) {
- log_debug("multicast kernel netlink message from PID %"PRIu32" ignored",
- snl.nl.nl_pid);
- errno = EAGAIN;
- return NULL;
- }
+ if (snl.nl.nl_pid > 0)
+ return log_debug_errno(EAGAIN, "Multicast kernel netlink message from PID %"PRIu32" ignored.", snl.nl.nl_pid);
}
cmsg = CMSG_FIRSTHDR(&smsg);
- if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
- log_debug("no sender credentials received, message ignored");
- errno = EAGAIN;
- return NULL;
- }
+ if (!cmsg || cmsg->cmsg_type != SCM_CREDENTIALS)
+ return log_debug_errno(EAGAIN, "No sender credentials received, message ignored.");
- cred = (struct ucred *)CMSG_DATA(cmsg);
- if (cred->uid != 0) {
- log_debug("sender uid="UID_FMT", message ignored", cred->uid);
- errno = EAGAIN;
- return NULL;
- }
+ cred = (struct ucred*) CMSG_DATA(cmsg);
+ if (cred->uid != 0)
+ return log_debug_errno(EAGAIN, "Sender uid="UID_FMT", message ignored.", cred->uid);
- if (memcmp(buf.raw, "libudev", 8) == 0) {
+ if (streq(buf.raw, "libudev")) {
/* udev message needs proper version magic */
- if (buf.nlh.magic != htobe32(UDEV_MONITOR_MAGIC)) {
- log_debug("unrecognized message signature (%x != %x)",
- buf.nlh.magic, htobe32(UDEV_MONITOR_MAGIC));
- errno = EAGAIN;
- return NULL;
- }
- if (buf.nlh.properties_off+32 > (size_t)buflen) {
- log_debug("message smaller than expected (%u > %zd)",
- buf.nlh.properties_off+32, buflen);
- errno = EAGAIN;
- return NULL;
- }
+ if (buf.nlh.magic != htobe32(UDEV_MONITOR_MAGIC))
+ return log_debug_errno(EAGAIN, "Invalid message signature (%x != %x)",
+ buf.nlh.magic, htobe32(UDEV_MONITOR_MAGIC));
+
+ if (buf.nlh.properties_off+32 > (size_t) buflen)
+ return log_debug_errno(EAGAIN, "Invalid message length (%u > %zd)",
+ buf.nlh.properties_off+32, buflen);
bufpos = buf.nlh.properties_off;
/* devices received from udev are always initialized */
is_initialized = true;
+
} else {
/* kernel message with header */
bufpos = strlen(buf.raw) + 1;
- if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) {
- log_debug("invalid message length");
- errno = EAGAIN;
- return NULL;
- }
+ if ((size_t) bufpos < sizeof("a@/d") || bufpos >= buflen)
+ return log_debug_errno(EAGAIN, "Invalid message length");
/* check message header */
- if (strstr(buf.raw, "@/") == NULL) {
- log_debug("unrecognized message header");
- errno = EAGAIN;
- return NULL;
- }
+ if (!strstr(buf.raw, "@/"))
+ return log_debug_errno(EAGAIN, "Invalid message header");
}
- udev_device = udev_device_new_from_nulstr(udev_monitor->udev, &buf.raw[bufpos], buflen - bufpos);
- if (!udev_device) {
- log_debug_errno(errno, "could not create device: %m");
- return NULL;
- }
+ r = device_new_from_nulstr(&device, (uint8_t*) &buf.raw[bufpos], buflen - bufpos);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to create device: %m");
if (is_initialized)
- udev_device_set_is_initialized(udev_device);
+ device_set_is_initialized(device);
/* skip device, if it does not pass the current filter */
- if (!passes_filter(udev_monitor, udev_device->device)) {
- struct pollfd pfd[1];
- int rc;
+ if (passes_filter(udev_monitor, device) <= 0)
+ return 0;
- udev_device_unref(udev_device);
+ *ret = TAKE_PTR(device);
+ return 1;
+}
- /* if something is queued, get next device */
- pfd[0].fd = udev_monitor->sock;
- pfd[0].events = POLLIN;
- rc = poll(pfd, 1, 0);
- if (rc > 0)
- goto retry;
+int udev_monitor_receive_sd_device(struct udev_monitor *udev_monitor, sd_device **ret) {
+ struct pollfd pfd = {
+ .fd = udev_monitor->sock,
+ .events = POLLIN,
+ };
+ int r;
- errno = EAGAIN;
- return NULL;
- }
+ assert(udev_monitor);
+ assert(ret);
- return udev_device;
+ for (;;) {
+ /* r == 0 means a device is received but it does not pass the current filter. */
+ r = udev_monitor_receive_device_one(udev_monitor, ret);
+ if (r != 0)
+ return r;
+
+ for (;;) {
+ /* wait next message */
+ r = poll(&pfd, 1, 0);
+ if (r < 0) {
+ if (IN_SET(errno, EINTR, EAGAIN))
+ continue;
+
+ return -errno;
+ } else if (r == 0)
+ return -EAGAIN;
+
+ /* receive next message */
+ break;
+ }
+ }
}
-int udev_monitor_receive_sd_device(struct udev_monitor *udev_monitor, sd_device **ret) {
- _cleanup_(udev_device_unrefp) struct udev_device *udev_device = NULL;
+/**
+ * udev_monitor_receive_device:
+ * @udev_monitor: udev monitor
+ *
+ * Receive data from the udev monitor socket, allocate a new udev
+ * device, fill in the received data, and return the device.
+ *
+ * Only socket connections with uid=0 are accepted.
+ *
+ * The monitor socket is by default set to NONBLOCK. A variant of poll() on
+ * the file descriptor returned by udev_monitor_get_fd() should to be used to
+ * wake up when new devices arrive, or alternatively the file descriptor
+ * switched into blocking mode.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, in case of an error
+ **/
+_public_ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monitor) {
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ int r;
- assert(ret);
+ assert_return(udev_monitor, NULL);
- udev_device = udev_monitor_receive_device(udev_monitor);
- if (!udev_device)
- return -errno;
+ r = udev_monitor_receive_sd_device(udev_monitor, &device);
+ if (r < 0) {
+ errno = -r;
+ return NULL;
+ }
- *ret = sd_device_ref(udev_device->device);
- return 0;
+ return udev_device_new(udev_monitor->udev, device);
}
int udev_monitor_send_device(struct udev_monitor *udev_monitor,
projects / thirdparty / systemd.git / commitdiff
