X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibudev%2Flibudev-monitor.c;h=c48ac78908a10d074b3d00897227142be71d8868;hp=f976da0b8a7f3ad271e8b341b9e9e499c03c1bc8;hb=e6ac88ddf213c431c678cfdac689577abbc14b28;hpb=29804cc1e0f37ee34301530fd7f1eb8550be464e diff --git a/src/libudev/libudev-monitor.c b/src/libudev/libudev-monitor.c index f976da0b8..c48ac7890 100644 --- a/src/libudev/libudev-monitor.c +++ b/src/libudev/libudev-monitor.c @@ -23,12 +23,8 @@ #include #include #include -#include -#include -#include +#include #include -#include -#include #include #include @@ -96,7 +92,7 @@ static struct udev_monitor *udev_monitor_new(struct udev *udev) { struct udev_monitor *udev_monitor; - udev_monitor = calloc(1, sizeof(struct udev_monitor)); + udev_monitor = new0(struct udev_monitor, 1); if (udev_monitor == NULL) return NULL; udev_monitor->refcount = 1; @@ -108,18 +104,19 @@ static struct udev_monitor *udev_monitor_new(struct udev *udev) /* we consider udev running when /dev is on devtmpfs */ static bool udev_has_devtmpfs(struct udev *udev) { - struct file_handle *h; - int mount_id; + + union file_handle_union h = FILE_HANDLE_INIT; _cleanup_fclose_ FILE *f = NULL; char line[LINE_MAX], *e; + int mount_id; int r; - h = alloca(MAX_HANDLE_SZ); - h->handle_bytes = MAX_HANDLE_SZ; - r = name_to_handle_at(AT_FDCWD, "/dev", h, &mount_id, 0); - if (r < 0) + r = name_to_handle_at(AT_FDCWD, "/dev", &h.handle, &mount_id, 0); + if (r < 0) { + if (errno != EOPNOTSUPP) + log_debug_errno(errno, "name_to_handle_at on /dev: %m"); return false; - + } f = fopen("/proc/self/mountinfo", "re"); if (!f) @@ -146,21 +143,6 @@ static bool udev_has_devtmpfs(struct udev *udev) { return false; } -/* we consider udev running when we have running udev service */ -static bool udev_has_service(struct udev *udev) { - struct udev_queue *queue; - bool active; - - queue = udev_queue_new(udev); - if (!queue) - return false; - - active = udev_queue_get_udev_is_active(queue); - udev_queue_unref(queue); - - return active; -} - struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd) { struct udev_monitor *udev_monitor; @@ -184,8 +166,8 @@ struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const c * We do not set a netlink multicast group here, so the socket * will not receive any messages. */ - if (!udev_has_service(udev) && !udev_has_devtmpfs(udev)) { - udev_dbg(udev, "the udev service seems not to be active, disable the monitor\n"); + if (access("/run/udev/control", F_OK) < 0 && !udev_has_devtmpfs(udev)) { + log_debug("the udev service seems not to be active, disable the monitor"); group = UDEV_MONITOR_NONE; } else group = UDEV_MONITOR_UDEV; @@ -201,7 +183,7 @@ struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const c if (fd < 0) { udev_monitor->sock = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_KOBJECT_UEVENT); if (udev_monitor->sock == -1) { - udev_err(udev, "error getting socket: %m\n"); + log_debug_errno(errno, "error getting socket: %m"); free(udev_monitor); return NULL; } @@ -418,12 +400,15 @@ _public_ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor) if (err == 0) udev_monitor->snl.nl.nl_pid = snl.nl.nl_pid; } else { - udev_err(udev_monitor->udev, "bind failed: %m\n"); + log_debug_errno(errno, "bind failed: %m"); return -errno; } /* enable receiving of sender credentials */ - setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); + err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); + if (err < 0) + log_debug_errno(errno, "setting SO_PASSCRED failed: %m"); + return 0; } @@ -590,9 +575,13 @@ _public_ struct udev_device *udev_monitor_receive_device(struct udev_monitor *ud struct cmsghdr *cmsg; union sockaddr_union snl; struct ucred *cred; - char buf[8192]; + union { + struct udev_monitor_netlink_header nlh; + char raw[8192]; + } buf; ssize_t buflen; ssize_t bufpos; + bool is_initialized = false; retry: if (udev_monitor == NULL) @@ -610,12 +599,12 @@ retry: buflen = recvmsg(udev_monitor->sock, &smsg, 0); if (buflen < 0) { if (errno != EINTR) - udev_dbg(udev_monitor->udev, "unable to receive message\n"); + log_debug("unable to receive message"); return NULL; } - if (buflen < 32 || (size_t)buflen >= sizeof(buf)) { - udev_dbg(udev_monitor->udev, "invalid message length\n"); + if (buflen < 32 || (smsg.msg_flags & MSG_TRUNC)) { + log_debug("invalid message length"); return NULL; } @@ -623,90 +612,70 @@ retry: /* 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) { - udev_dbg(udev_monitor->udev, "unicast netlink message ignored\n"); + log_debug("unicast netlink message ignored"); return NULL; } } else if (snl.nl.nl_groups == UDEV_MONITOR_KERNEL) { if (snl.nl.nl_pid > 0) { - udev_dbg(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n", - snl.nl.nl_pid); + log_debug("multicast kernel netlink message from PID %"PRIu32" ignored", + snl.nl.nl_pid); return NULL; } } cmsg = CMSG_FIRSTHDR(&smsg); if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) { - udev_dbg(udev_monitor->udev, "no sender credentials received, message ignored\n"); + log_debug("no sender credentials received, message ignored"); return NULL; } cred = (struct ucred *)CMSG_DATA(cmsg); if (cred->uid != 0) { - udev_dbg(udev_monitor->udev, "sender uid=%d, message ignored\n", cred->uid); + log_debug("sender uid="UID_FMT", message ignored", cred->uid); return NULL; } - udev_device = udev_device_new(udev_monitor->udev); - if (udev_device == NULL) - return NULL; - - if (memcmp(buf, "libudev", 8) == 0) { - struct udev_monitor_netlink_header *nlh; - + if (memcmp(buf.raw, "libudev", 8) == 0) { /* udev message needs proper version magic */ - nlh = (struct udev_monitor_netlink_header *) buf; - if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) { - udev_err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n", - nlh->magic, htonl(UDEV_MONITOR_MAGIC)); - udev_device_unref(udev_device); + if (buf.nlh.magic != htonl(UDEV_MONITOR_MAGIC)) { + log_debug("unrecognized message signature (%x != %x)", + buf.nlh.magic, htonl(UDEV_MONITOR_MAGIC)); return NULL; } - if (nlh->properties_off+32 > (size_t)buflen) { - udev_device_unref(udev_device); + if (buf.nlh.properties_off+32 > (size_t)buflen) { + log_debug("message smaller than expected (%u > %zd)", + buf.nlh.properties_off+32, buflen); return NULL; } - bufpos = nlh->properties_off; + bufpos = buf.nlh.properties_off; /* devices received from udev are always initialized */ - udev_device_set_is_initialized(udev_device); + is_initialized = true; } else { /* kernel message with header */ - bufpos = strlen(buf) + 1; + bufpos = strlen(buf.raw) + 1; if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) { - udev_dbg(udev_monitor->udev, "invalid message length\n"); - udev_device_unref(udev_device); + log_debug("invalid message length"); return NULL; } /* check message header */ - if (strstr(buf, "@/") == NULL) { - udev_dbg(udev_monitor->udev, "unrecognized message header\n"); - udev_device_unref(udev_device); + if (strstr(buf.raw, "@/") == NULL) { + log_debug("unrecognized message header"); return NULL; } } - udev_device_set_info_loaded(udev_device); - - while (bufpos < buflen) { - char *key; - size_t keylen; - - key = &buf[bufpos]; - keylen = strlen(key); - if (keylen == 0) - break; - bufpos += keylen + 1; - udev_device_add_property_from_string_parse(udev_device, key); - } - - if (udev_device_add_property_from_string_parse_finish(udev_device) < 0) { - udev_dbg(udev_monitor->udev, "missing values, invalid device\n"); - udev_device_unref(udev_device); + udev_device = udev_device_new_from_nulstr(udev_monitor->udev, &buf.raw[bufpos], buflen - bufpos); + if (!udev_device) { + log_debug("could not create device: %m"); return NULL; } + if (is_initialized) + udev_device_set_is_initialized(udev_device); + /* skip device, if it does not pass the current filter */ if (!passes_filter(udev_monitor, udev_device)) { struct pollfd pfd[1]; @@ -729,32 +698,36 @@ retry: int udev_monitor_send_device(struct udev_monitor *udev_monitor, struct udev_monitor *destination, struct udev_device *udev_device) { - const char *buf; - ssize_t blen; - ssize_t count; - struct msghdr smsg; - struct iovec iov[2]; - const char *val; - struct udev_monitor_netlink_header nlh; + const char *buf, *val; + ssize_t blen, count; + struct udev_monitor_netlink_header nlh = { + .prefix = "libudev", + .magic = htonl(UDEV_MONITOR_MAGIC), + .header_size = sizeof nlh, + }; + struct iovec iov[2] = { + { .iov_base = &nlh, .iov_len = sizeof nlh }, + }; + struct msghdr smsg = { + .msg_iov = iov, + .msg_iovlen = 2, + }; struct udev_list_entry *list_entry; uint64_t tag_bloom_bits; blen = udev_device_get_properties_monitor_buf(udev_device, &buf); - if (blen < 32) + if (blen < 32) { + log_debug("device buffer is too small to contain a valid device"); return -EINVAL; + } - /* add versioned header */ - memzero(&nlh, sizeof(struct udev_monitor_netlink_header)); - memcpy(nlh.prefix, "libudev", 8); - nlh.magic = htonl(UDEV_MONITOR_MAGIC); - nlh.header_size = sizeof(struct udev_monitor_netlink_header); + /* fill in versioned header */ val = udev_device_get_subsystem(udev_device); nlh.filter_subsystem_hash = htonl(util_string_hash32(val)); + val = udev_device_get_devtype(udev_device); if (val != NULL) nlh.filter_devtype_hash = htonl(util_string_hash32(val)); - iov[0].iov_base = &nlh; - iov[0].iov_len = sizeof(struct udev_monitor_netlink_header); /* add tag bloom filter */ tag_bloom_bits = 0; @@ -771,22 +744,27 @@ int udev_monitor_send_device(struct udev_monitor *udev_monitor, iov[1].iov_base = (char *)buf; iov[1].iov_len = blen; - memzero(&smsg, sizeof(struct msghdr)); - smsg.msg_iov = iov; - smsg.msg_iovlen = 2; /* * Use custom address for target, or the default one. * * If we send to a multicast group, we will get * ECONNREFUSED, which is expected. */ - if (destination != NULL) + if (destination) smsg.msg_name = &destination->snl; else smsg.msg_name = &udev_monitor->snl_destination; smsg.msg_namelen = sizeof(struct sockaddr_nl); count = sendmsg(udev_monitor->sock, &smsg, 0); - udev_dbg(udev_monitor->udev, "passed %zi bytes to netlink monitor %p\n", count, udev_monitor); + if (count < 0) { + if (!destination && errno == ECONNREFUSED) { + log_debug("passed unknown number of bytes to netlink monitor %p", udev_monitor); + return 0; + } else + return -errno; + } + + log_debug("passed %zi bytes to netlink monitor %p", count, udev_monitor); return count; }