X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibudev-monitor.c;h=0b57072158cc49c7c35d857b7a428d7f2d298f60;hp=f2f39f95829dbae2fe344c541595f13289e54ce3;hb=46505c52a61cbc9c9465eb676d3693bb32e65615;hpb=ad29a9f14fa8b1932c0e418bfcf1c10ce6a35a33 diff --git a/src/libudev-monitor.c b/src/libudev-monitor.c index f2f39f958..0b5707215 100644 --- a/src/libudev-monitor.c +++ b/src/libudev-monitor.c @@ -40,61 +40,61 @@ * Opaque object handling an event source. */ struct udev_monitor { - struct udev *udev; - int refcount; - int sock; - struct sockaddr_nl snl; - struct sockaddr_nl snl_trusted_sender; - struct sockaddr_nl snl_destination; - struct sockaddr_un sun; - socklen_t addrlen; - struct udev_list filter_subsystem_list; - struct udev_list filter_tag_list; - bool bound; + struct udev *udev; + int refcount; + int sock; + struct sockaddr_nl snl; + struct sockaddr_nl snl_trusted_sender; + struct sockaddr_nl snl_destination; + struct sockaddr_un sun; + socklen_t addrlen; + struct udev_list filter_subsystem_list; + struct udev_list filter_tag_list; + bool bound; }; enum udev_monitor_netlink_group { - UDEV_MONITOR_NONE, - UDEV_MONITOR_KERNEL, - UDEV_MONITOR_UDEV, + UDEV_MONITOR_NONE, + UDEV_MONITOR_KERNEL, + UDEV_MONITOR_UDEV, }; -#define UDEV_MONITOR_MAGIC 0xfeedcafe +#define UDEV_MONITOR_MAGIC 0xfeedcafe struct udev_monitor_netlink_header { - /* "libudev" prefix to distinguish libudev and kernel messages */ - char prefix[8]; - /* - * magic to protect against daemon <-> library message format mismatch - * used in the kernel from socket filter rules; needs to be stored in network order - */ - unsigned int magic; - /* total length of header structure known to the sender */ - unsigned int header_size; - /* properties string buffer */ - unsigned int properties_off; - unsigned int properties_len; - /* - * hashes of primary device properties strings, to let libudev subscribers - * use in-kernel socket filters; values need to be stored in network order - */ - unsigned int filter_subsystem_hash; - unsigned int filter_devtype_hash; - unsigned int filter_tag_bloom_hi; - unsigned int filter_tag_bloom_lo; + /* "libudev" prefix to distinguish libudev and kernel messages */ + char prefix[8]; + /* + * magic to protect against daemon <-> library message format mismatch + * used in the kernel from socket filter rules; needs to be stored in network order + */ + unsigned int magic; + /* total length of header structure known to the sender */ + unsigned int header_size; + /* properties string buffer */ + unsigned int properties_off; + unsigned int properties_len; + /* + * hashes of primary device properties strings, to let libudev subscribers + * use in-kernel socket filters; values need to be stored in network order + */ + unsigned int filter_subsystem_hash; + unsigned int filter_devtype_hash; + unsigned int filter_tag_bloom_hi; + unsigned int filter_tag_bloom_lo; }; static struct udev_monitor *udev_monitor_new(struct udev *udev) { - struct udev_monitor *udev_monitor; - - udev_monitor = calloc(1, sizeof(struct udev_monitor)); - if (udev_monitor == NULL) - return NULL; - udev_monitor->refcount = 1; - udev_monitor->udev = udev; - udev_list_init(udev, &udev_monitor->filter_subsystem_list, false); - udev_list_init(udev, &udev_monitor->filter_tag_list, true); - return udev_monitor; + struct udev_monitor *udev_monitor; + + udev_monitor = calloc(1, sizeof(struct udev_monitor)); + if (udev_monitor == NULL) + return NULL; + udev_monitor->refcount = 1; + udev_monitor->udev = udev; + udev_list_init(udev, &udev_monitor->filter_subsystem_list, false); + udev_list_init(udev, &udev_monitor->filter_tag_list, true); + return udev_monitor; } /** @@ -124,85 +124,85 @@ static struct udev_monitor *udev_monitor_new(struct udev *udev) **/ UDEV_EXPORT struct udev_monitor *udev_monitor_new_from_socket(struct udev *udev, const char *socket_path) { - struct udev_monitor *udev_monitor; - struct stat statbuf; - - if (udev == NULL) - return NULL; - if (socket_path == NULL) - return NULL; - udev_monitor = udev_monitor_new(udev); - if (udev_monitor == NULL) - return NULL; - - udev_monitor->sun.sun_family = AF_LOCAL; - if (socket_path[0] == '@') { - /* translate leading '@' to abstract namespace */ - util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path); - udev_monitor->sun.sun_path[0] = '\0'; - udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path); - } else if (stat(socket_path, &statbuf) == 0 && S_ISSOCK(statbuf.st_mode)) { - /* existing socket file */ - util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path); - udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path); - } else { - /* no socket file, assume abstract namespace socket */ - util_strscpy(&udev_monitor->sun.sun_path[1], sizeof(udev_monitor->sun.sun_path)-1, socket_path); - udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path)+1; - } - udev_monitor->sock = socket(AF_LOCAL, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0); - if (udev_monitor->sock == -1) { - err(udev, "error getting socket: %m\n"); - free(udev_monitor); - return NULL; - } - - dbg(udev, "monitor %p created with '%s'\n", udev_monitor, socket_path); - return udev_monitor; + struct udev_monitor *udev_monitor; + struct stat statbuf; + + if (udev == NULL) + return NULL; + if (socket_path == NULL) + return NULL; + udev_monitor = udev_monitor_new(udev); + if (udev_monitor == NULL) + return NULL; + + udev_monitor->sun.sun_family = AF_LOCAL; + if (socket_path[0] == '@') { + /* translate leading '@' to abstract namespace */ + util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path); + udev_monitor->sun.sun_path[0] = '\0'; + udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path); + } else if (stat(socket_path, &statbuf) == 0 && S_ISSOCK(statbuf.st_mode)) { + /* existing socket file */ + util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path); + udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path); + } else { + /* no socket file, assume abstract namespace socket */ + util_strscpy(&udev_monitor->sun.sun_path[1], sizeof(udev_monitor->sun.sun_path)-1, socket_path); + udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path)+1; + } + udev_monitor->sock = socket(AF_LOCAL, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0); + if (udev_monitor->sock == -1) { + err(udev, "error getting socket: %m\n"); + free(udev_monitor); + return NULL; + } + + dbg(udev, "monitor %p created with '%s'\n", udev_monitor, socket_path); + return udev_monitor; } struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd) { - struct udev_monitor *udev_monitor; - unsigned int group; - - if (udev == NULL) - return NULL; - - if (name == NULL) - group = UDEV_MONITOR_NONE; - else if (strcmp(name, "udev") == 0) - group = UDEV_MONITOR_UDEV; - else if (strcmp(name, "kernel") == 0) - group = UDEV_MONITOR_KERNEL; - else - return NULL; - - udev_monitor = udev_monitor_new(udev); - if (udev_monitor == NULL) - return NULL; - - if (fd < 0) { - udev_monitor->sock = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_KOBJECT_UEVENT); - if (udev_monitor->sock == -1) { - err(udev, "error getting socket: %m\n"); - free(udev_monitor); - return NULL; - } - } else { - udev_monitor->bound = true; - udev_monitor->sock = fd; - } - - udev_monitor->snl.nl_family = AF_NETLINK; - udev_monitor->snl.nl_groups = group; - - /* default destination for sending */ - udev_monitor->snl_destination.nl_family = AF_NETLINK; - udev_monitor->snl_destination.nl_groups = UDEV_MONITOR_UDEV; - - dbg(udev, "monitor %p created with NETLINK_KOBJECT_UEVENT (%u)\n", udev_monitor, group); - return udev_monitor; + struct udev_monitor *udev_monitor; + unsigned int group; + + if (udev == NULL) + return NULL; + + if (name == NULL) + group = UDEV_MONITOR_NONE; + else if (strcmp(name, "udev") == 0) + group = UDEV_MONITOR_UDEV; + else if (strcmp(name, "kernel") == 0) + group = UDEV_MONITOR_KERNEL; + else + return NULL; + + udev_monitor = udev_monitor_new(udev); + if (udev_monitor == NULL) + return NULL; + + if (fd < 0) { + udev_monitor->sock = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_KOBJECT_UEVENT); + if (udev_monitor->sock == -1) { + err(udev, "error getting socket: %m\n"); + free(udev_monitor); + return NULL; + } + } else { + udev_monitor->bound = true; + udev_monitor->sock = fd; + } + + udev_monitor->snl.nl_family = AF_NETLINK; + udev_monitor->snl.nl_groups = group; + + /* default destination for sending */ + udev_monitor->snl_destination.nl_family = AF_NETLINK; + udev_monitor->snl_destination.nl_groups = UDEV_MONITOR_UDEV; + + dbg(udev, "monitor %p created with NETLINK_KOBJECT_UEVENT (%u)\n", udev_monitor, group); + return udev_monitor; } /** @@ -229,30 +229,30 @@ struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const c **/ UDEV_EXPORT struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char *name) { - return udev_monitor_new_from_netlink_fd(udev, name, -1); + return udev_monitor_new_from_netlink_fd(udev, name, -1); } static inline void bpf_stmt(struct sock_filter *inss, unsigned int *i, - unsigned short code, unsigned int data) + unsigned short code, unsigned int data) { - struct sock_filter *ins = &inss[*i]; + struct sock_filter *ins = &inss[*i]; - ins->code = code; - ins->k = data; - (*i)++; + ins->code = code; + ins->k = data; + (*i)++; } static inline void bpf_jmp(struct sock_filter *inss, unsigned int *i, - unsigned short code, unsigned int data, - unsigned short jt, unsigned short jf) + unsigned short code, unsigned int data, + unsigned short jt, unsigned short jf) { - struct sock_filter *ins = &inss[*i]; + struct sock_filter *ins = &inss[*i]; - ins->code = code; - ins->jt = jt; - ins->jf = jf; - ins->k = data; - (*i)++; + ins->code = code; + ins->jt = jt; + ins->jf = jf; + ins->k = data; + (*i)++; } /** @@ -266,107 +266,107 @@ static inline void bpf_jmp(struct sock_filter *inss, unsigned int *i, */ UDEV_EXPORT int udev_monitor_filter_update(struct udev_monitor *udev_monitor) { - struct sock_filter ins[512]; - struct sock_fprog filter; - unsigned int i; - struct udev_list_entry *list_entry; - int err; - - if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL && - udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL) - return 0; - - memset(ins, 0x00, sizeof(ins)); - i = 0; - - /* load magic in A */ - bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, magic)); - /* jump if magic matches */ - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, UDEV_MONITOR_MAGIC, 1, 0); - /* wrong magic, pass packet */ - bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); - - if (udev_list_get_entry(&udev_monitor->filter_tag_list) != NULL) { - int tag_matches; - - /* count tag matches, to calculate end of tag match block */ - tag_matches = 0; - udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) - tag_matches++; - - /* add all tags matches */ - udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) { - uint64_t tag_bloom_bits = util_string_bloom64(udev_list_entry_get_name(list_entry)); - uint32_t tag_bloom_hi = tag_bloom_bits >> 32; - uint32_t tag_bloom_lo = tag_bloom_bits & 0xffffffff; - - /* load device bloom bits in A */ - bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_hi)); - /* clear bits (tag bits & bloom bits) */ - bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_hi); - /* jump to next tag if it does not match */ - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_hi, 0, 3); - - /* load device bloom bits in A */ - bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_lo)); - /* clear bits (tag bits & bloom bits) */ - bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_lo); - /* jump behind end of tag match block if tag matches */ - tag_matches--; - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_lo, 1 + (tag_matches * 6), 0); - } - - /* nothing matched, drop packet */ - bpf_stmt(ins, &i, BPF_RET|BPF_K, 0); - } - - /* add all subsystem matches */ - if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) != NULL) { - udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) { - unsigned int hash = util_string_hash32(udev_list_entry_get_name(list_entry)); - - /* load device subsystem value in A */ - bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_subsystem_hash)); - if (udev_list_entry_get_value(list_entry) == NULL) { - /* jump if subsystem does not match */ - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1); - } else { - /* jump if subsystem does not match */ - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 3); - - /* load device devtype value in A */ - bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_devtype_hash)); - /* jump if value does not match */ - hash = util_string_hash32(udev_list_entry_get_value(list_entry)); - bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1); - } - - /* matched, pass packet */ - bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); - - if (i+1 >= ARRAY_SIZE(ins)) - return -1; - } - - /* nothing matched, drop packet */ - bpf_stmt(ins, &i, BPF_RET|BPF_K, 0); - } - - /* matched, pass packet */ - bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); - - /* install filter */ - memset(&filter, 0x00, sizeof(filter)); - filter.len = i; - filter.filter = ins; - err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)); - return err; + struct sock_filter ins[512]; + struct sock_fprog filter; + unsigned int i; + struct udev_list_entry *list_entry; + int err; + + if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL && + udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL) + return 0; + + memset(ins, 0x00, sizeof(ins)); + i = 0; + + /* load magic in A */ + bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, magic)); + /* jump if magic matches */ + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, UDEV_MONITOR_MAGIC, 1, 0); + /* wrong magic, pass packet */ + bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); + + if (udev_list_get_entry(&udev_monitor->filter_tag_list) != NULL) { + int tag_matches; + + /* count tag matches, to calculate end of tag match block */ + tag_matches = 0; + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) + tag_matches++; + + /* add all tags matches */ + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) { + uint64_t tag_bloom_bits = util_string_bloom64(udev_list_entry_get_name(list_entry)); + uint32_t tag_bloom_hi = tag_bloom_bits >> 32; + uint32_t tag_bloom_lo = tag_bloom_bits & 0xffffffff; + + /* load device bloom bits in A */ + bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_hi)); + /* clear bits (tag bits & bloom bits) */ + bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_hi); + /* jump to next tag if it does not match */ + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_hi, 0, 3); + + /* load device bloom bits in A */ + bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_lo)); + /* clear bits (tag bits & bloom bits) */ + bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_lo); + /* jump behind end of tag match block if tag matches */ + tag_matches--; + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_lo, 1 + (tag_matches * 6), 0); + } + + /* nothing matched, drop packet */ + bpf_stmt(ins, &i, BPF_RET|BPF_K, 0); + } + + /* add all subsystem matches */ + if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) != NULL) { + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) { + unsigned int hash = util_string_hash32(udev_list_entry_get_name(list_entry)); + + /* load device subsystem value in A */ + bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_subsystem_hash)); + if (udev_list_entry_get_value(list_entry) == NULL) { + /* jump if subsystem does not match */ + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1); + } else { + /* jump if subsystem does not match */ + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 3); + + /* load device devtype value in A */ + bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_devtype_hash)); + /* jump if value does not match */ + hash = util_string_hash32(udev_list_entry_get_value(list_entry)); + bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1); + } + + /* matched, pass packet */ + bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); + + if (i+1 >= ARRAY_SIZE(ins)) + return -1; + } + + /* nothing matched, drop packet */ + bpf_stmt(ins, &i, BPF_RET|BPF_K, 0); + } + + /* matched, pass packet */ + bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff); + + /* install filter */ + memset(&filter, 0x00, sizeof(filter)); + filter.len = i; + filter.filter = ins; + err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)); + return err; } int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct udev_monitor *sender) { - udev_monitor->snl_trusted_sender.nl_pid = sender->snl.nl_pid; - return 0; + udev_monitor->snl_trusted_sender.nl_pid = sender->snl.nl_pid; + return 0; } /** * udev_monitor_enable_receiving: @@ -378,49 +378,49 @@ int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct */ UDEV_EXPORT int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor) { - int err = 0; - const int on = 1; - - if (udev_monitor->sun.sun_family != 0) { - if (!udev_monitor->bound) { - err = bind(udev_monitor->sock, - (struct sockaddr *)&udev_monitor->sun, udev_monitor->addrlen); - if (err == 0) - udev_monitor->bound = true; - } - } else if (udev_monitor->snl.nl_family != 0) { - udev_monitor_filter_update(udev_monitor); - if (!udev_monitor->bound) { - err = bind(udev_monitor->sock, - (struct sockaddr *)&udev_monitor->snl, sizeof(struct sockaddr_nl)); - if (err == 0) - udev_monitor->bound = true; - } - if (err == 0) { - struct sockaddr_nl snl; - socklen_t addrlen; - - /* - * get the address the kernel has assigned us - * it is usually, but not necessarily the pid - */ - addrlen = sizeof(struct sockaddr_nl); - err = getsockname(udev_monitor->sock, (struct sockaddr *)&snl, &addrlen); - if (err == 0) - udev_monitor->snl.nl_pid = snl.nl_pid; - } - } else { - return -EINVAL; - } - - if (err < 0) { - err(udev_monitor->udev, "bind failed: %m\n"); - return err; - } - - /* enable receiving of sender credentials */ - setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); - return 0; + int err = 0; + const int on = 1; + + if (udev_monitor->sun.sun_family != 0) { + if (!udev_monitor->bound) { + err = bind(udev_monitor->sock, + (struct sockaddr *)&udev_monitor->sun, udev_monitor->addrlen); + if (err == 0) + udev_monitor->bound = true; + } + } else if (udev_monitor->snl.nl_family != 0) { + udev_monitor_filter_update(udev_monitor); + if (!udev_monitor->bound) { + err = bind(udev_monitor->sock, + (struct sockaddr *)&udev_monitor->snl, sizeof(struct sockaddr_nl)); + if (err == 0) + udev_monitor->bound = true; + } + if (err == 0) { + struct sockaddr_nl snl; + socklen_t addrlen; + + /* + * get the address the kernel has assigned us + * it is usually, but not necessarily the pid + */ + addrlen = sizeof(struct sockaddr_nl); + err = getsockname(udev_monitor->sock, (struct sockaddr *)&snl, &addrlen); + if (err == 0) + udev_monitor->snl.nl_pid = snl.nl_pid; + } + } else { + return -EINVAL; + } + + if (err < 0) { + err(udev_monitor->udev, "bind failed: %m\n"); + return err; + } + + /* enable receiving of sender credentials */ + setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); + return 0; } /** @@ -435,18 +435,18 @@ UDEV_EXPORT int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor) */ UDEV_EXPORT int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size) { - if (udev_monitor == NULL) - return -1; - return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size)); + if (udev_monitor == NULL) + return -1; + return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size)); } int udev_monitor_disconnect(struct udev_monitor *udev_monitor) { - int err; + int err; - err = close(udev_monitor->sock); - udev_monitor->sock = -1; - return err; + err = close(udev_monitor->sock); + udev_monitor->sock = -1; + return err; } /** @@ -459,10 +459,10 @@ int udev_monitor_disconnect(struct udev_monitor *udev_monitor) **/ UDEV_EXPORT struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor) { - if (udev_monitor == NULL) - return NULL; - udev_monitor->refcount++; - return udev_monitor; + if (udev_monitor == NULL) + return NULL; + udev_monitor->refcount++; + return udev_monitor; } /** @@ -476,17 +476,17 @@ UDEV_EXPORT struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_moni **/ UDEV_EXPORT void udev_monitor_unref(struct udev_monitor *udev_monitor) { - if (udev_monitor == NULL) - return; - udev_monitor->refcount--; - if (udev_monitor->refcount > 0) - return; - if (udev_monitor->sock >= 0) - close(udev_monitor->sock); - udev_list_cleanup(&udev_monitor->filter_subsystem_list); - udev_list_cleanup(&udev_monitor->filter_tag_list); - dbg(udev_monitor->udev, "monitor %p released\n", udev_monitor); - free(udev_monitor); + if (udev_monitor == NULL) + return; + udev_monitor->refcount--; + if (udev_monitor->refcount > 0) + return; + if (udev_monitor->sock >= 0) + close(udev_monitor->sock); + udev_list_cleanup(&udev_monitor->filter_subsystem_list); + udev_list_cleanup(&udev_monitor->filter_tag_list); + dbg(udev_monitor->udev, "monitor %p released\n", udev_monitor); + free(udev_monitor); } /** @@ -499,9 +499,9 @@ UDEV_EXPORT void udev_monitor_unref(struct udev_monitor *udev_monitor) **/ UDEV_EXPORT struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor) { - if (udev_monitor == NULL) - return NULL; - return udev_monitor->udev; + if (udev_monitor == NULL) + return NULL; + return udev_monitor->udev; } /** @@ -514,47 +514,47 @@ UDEV_EXPORT struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor **/ UDEV_EXPORT int udev_monitor_get_fd(struct udev_monitor *udev_monitor) { - if (udev_monitor == NULL) - return -1; - return udev_monitor->sock; + if (udev_monitor == NULL) + return -1; + return udev_monitor->sock; } static int passes_filter(struct udev_monitor *udev_monitor, struct udev_device *udev_device) { - struct udev_list_entry *list_entry; - - if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL) - goto tag; - udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) { - const char *subsys = udev_list_entry_get_name(list_entry); - const char *dsubsys = udev_device_get_subsystem(udev_device); - const char *devtype; - const char *ddevtype; - - if (strcmp(dsubsys, subsys) != 0) - continue; - - devtype = udev_list_entry_get_value(list_entry); - if (devtype == NULL) - goto tag; - ddevtype = udev_device_get_devtype(udev_device); - if (ddevtype == NULL) - continue; - if (strcmp(ddevtype, devtype) == 0) - goto tag; - } - return 0; + struct udev_list_entry *list_entry; + + if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL) + goto tag; + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) { + const char *subsys = udev_list_entry_get_name(list_entry); + const char *dsubsys = udev_device_get_subsystem(udev_device); + const char *devtype; + const char *ddevtype; + + if (strcmp(dsubsys, subsys) != 0) + continue; + + devtype = udev_list_entry_get_value(list_entry); + if (devtype == NULL) + goto tag; + ddevtype = udev_device_get_devtype(udev_device); + if (ddevtype == NULL) + continue; + if (strcmp(ddevtype, devtype) == 0) + goto tag; + } + return 0; tag: - if (udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL) - return 1; - udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) { - const char *tag = udev_list_entry_get_name(list_entry); - - if (udev_device_has_tag(udev_device, tag)) - return 1; - } - return 0; + if (udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL) + return 1; + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) { + const char *tag = udev_list_entry_get_name(list_entry); + + if (udev_device_has_tag(udev_device, tag)) + return 1; + } + return 0; } /** @@ -573,242 +573,242 @@ tag: **/ UDEV_EXPORT 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; - struct sockaddr_nl snl; - struct ucred *cred; - char buf[8192]; - ssize_t buflen; - ssize_t bufpos; - struct udev_monitor_netlink_header *nlh; + struct udev_device *udev_device; + struct msghdr smsg; + struct iovec iov; + char cred_msg[CMSG_SPACE(sizeof(struct ucred))]; + struct cmsghdr *cmsg; + struct sockaddr_nl snl; + struct ucred *cred; + char buf[8192]; + ssize_t buflen; + ssize_t bufpos; + struct udev_monitor_netlink_header *nlh; retry: - if (udev_monitor == NULL) - return NULL; - memset(buf, 0x00, sizeof(buf)); - iov.iov_base = &buf; - iov.iov_len = sizeof(buf); - 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); - - if (udev_monitor->snl.nl_family != 0) { - smsg.msg_name = &snl; - smsg.msg_namelen = sizeof(snl); - } - - buflen = recvmsg(udev_monitor->sock, &smsg, 0); - if (buflen < 0) { - if (errno != EINTR) - info(udev_monitor->udev, "unable to receive message\n"); - return NULL; - } - - if (buflen < 32 || (size_t)buflen >= sizeof(buf)) { - info(udev_monitor->udev, "invalid message length\n"); - return NULL; - } - - if (udev_monitor->snl.nl_family != 0) { - if (snl.nl_groups == 0) { - /* unicast message, check if we trust the sender */ - if (udev_monitor->snl_trusted_sender.nl_pid == 0 || - snl.nl_pid != udev_monitor->snl_trusted_sender.nl_pid) { - info(udev_monitor->udev, "unicast netlink message ignored\n"); - return NULL; - } - } else if (snl.nl_groups == UDEV_MONITOR_KERNEL) { - if (snl.nl_pid > 0) { - info(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n", - snl.nl_pid); - return NULL; - } - } - } - - cmsg = CMSG_FIRSTHDR(&smsg); - if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) { - info(udev_monitor->udev, "no sender credentials received, message ignored\n"); - return NULL; - } - - cred = (struct ucred *)CMSG_DATA(cmsg); - if (cred->uid != 0) { - info(udev_monitor->udev, "sender uid=%d, message ignored\n", cred->uid); - return NULL; - } - - if (memcmp(buf, "libudev", 8) == 0) { - /* udev message needs proper version magic */ - nlh = (struct udev_monitor_netlink_header *) buf; - if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) { - err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n", - nlh->magic, htonl(UDEV_MONITOR_MAGIC)); - return NULL; - } - if (nlh->properties_off+32 > buflen) - return NULL; - bufpos = nlh->properties_off; - } else { - /* kernel message with header */ - bufpos = strlen(buf) + 1; - if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) { - info(udev_monitor->udev, "invalid message length\n"); - return NULL; - } - - /* check message header */ - if (strstr(buf, "@/") == NULL) { - info(udev_monitor->udev, "unrecognized message header\n"); - return NULL; - } - } - - udev_device = udev_device_new(udev_monitor->udev); - if (udev_device == NULL) - 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) { - info(udev_monitor->udev, "missing values, invalid device\n"); - udev_device_unref(udev_device); - return NULL; - } - - /* skip device, if it does not pass the current filter */ - if (!passes_filter(udev_monitor, udev_device)) { - struct pollfd pfd[1]; - int rc; - - udev_device_unref(udev_device); - - /* 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; - return NULL; - } - - return udev_device; + if (udev_monitor == NULL) + return NULL; + memset(buf, 0x00, sizeof(buf)); + iov.iov_base = &buf; + iov.iov_len = sizeof(buf); + 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); + + if (udev_monitor->snl.nl_family != 0) { + smsg.msg_name = &snl; + smsg.msg_namelen = sizeof(snl); + } + + buflen = recvmsg(udev_monitor->sock, &smsg, 0); + if (buflen < 0) { + if (errno != EINTR) + info(udev_monitor->udev, "unable to receive message\n"); + return NULL; + } + + if (buflen < 32 || (size_t)buflen >= sizeof(buf)) { + info(udev_monitor->udev, "invalid message length\n"); + return NULL; + } + + if (udev_monitor->snl.nl_family != 0) { + if (snl.nl_groups == 0) { + /* unicast message, check if we trust the sender */ + if (udev_monitor->snl_trusted_sender.nl_pid == 0 || + snl.nl_pid != udev_monitor->snl_trusted_sender.nl_pid) { + info(udev_monitor->udev, "unicast netlink message ignored\n"); + return NULL; + } + } else if (snl.nl_groups == UDEV_MONITOR_KERNEL) { + if (snl.nl_pid > 0) { + info(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n", + snl.nl_pid); + return NULL; + } + } + } + + cmsg = CMSG_FIRSTHDR(&smsg); + if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) { + info(udev_monitor->udev, "no sender credentials received, message ignored\n"); + return NULL; + } + + cred = (struct ucred *)CMSG_DATA(cmsg); + if (cred->uid != 0) { + info(udev_monitor->udev, "sender uid=%d, message ignored\n", cred->uid); + return NULL; + } + + if (memcmp(buf, "libudev", 8) == 0) { + /* udev message needs proper version magic */ + nlh = (struct udev_monitor_netlink_header *) buf; + if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) { + err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n", + nlh->magic, htonl(UDEV_MONITOR_MAGIC)); + return NULL; + } + if (nlh->properties_off+32 > buflen) + return NULL; + bufpos = nlh->properties_off; + } else { + /* kernel message with header */ + bufpos = strlen(buf) + 1; + if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) { + info(udev_monitor->udev, "invalid message length\n"); + return NULL; + } + + /* check message header */ + if (strstr(buf, "@/") == NULL) { + info(udev_monitor->udev, "unrecognized message header\n"); + return NULL; + } + } + + udev_device = udev_device_new(udev_monitor->udev); + if (udev_device == NULL) + 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) { + info(udev_monitor->udev, "missing values, invalid device\n"); + udev_device_unref(udev_device); + return NULL; + } + + /* skip device, if it does not pass the current filter */ + if (!passes_filter(udev_monitor, udev_device)) { + struct pollfd pfd[1]; + int rc; + + udev_device_unref(udev_device); + + /* 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; + return NULL; + } + + return udev_device; } int udev_monitor_send_device(struct udev_monitor *udev_monitor, - struct udev_monitor *destination, struct udev_device *udev_device) + struct udev_monitor *destination, struct udev_device *udev_device) { - const char *buf; - ssize_t blen; - ssize_t count; - - blen = udev_device_get_properties_monitor_buf(udev_device, &buf); - if (blen < 32) - return -EINVAL; - - if (udev_monitor->sun.sun_family != 0) { - struct msghdr smsg; - struct iovec iov[2]; - const char *action; - char header[2048]; - char *s; - - /* header @ */ - action = udev_device_get_action(udev_device); - if (action == NULL) - return -EINVAL; - s = header; - if (util_strpcpyl(&s, sizeof(header), action, "@", udev_device_get_devpath(udev_device), NULL) == 0) - return -EINVAL; - iov[0].iov_base = header; - iov[0].iov_len = (s - header)+1; - - /* add properties list */ - iov[1].iov_base = (char *)buf; - iov[1].iov_len = blen; - - memset(&smsg, 0x00, sizeof(struct msghdr)); - smsg.msg_iov = iov; - smsg.msg_iovlen = 2; - smsg.msg_name = &udev_monitor->sun; - smsg.msg_namelen = udev_monitor->addrlen; - count = sendmsg(udev_monitor->sock, &smsg, 0); - info(udev_monitor->udev, "passed %zi bytes to socket monitor %p\n", count, udev_monitor); - return count; - } - - if (udev_monitor->snl.nl_family != 0) { - struct msghdr smsg; - struct iovec iov[2]; - const char *val; - struct udev_monitor_netlink_header nlh; - struct udev_list_entry *list_entry; - uint64_t tag_bloom_bits; - - /* add versioned header */ - memset(&nlh, 0x00, 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); - 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; - udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device)) - tag_bloom_bits |= util_string_bloom64(udev_list_entry_get_name(list_entry)); - if (tag_bloom_bits > 0) { - nlh.filter_tag_bloom_hi = htonl(tag_bloom_bits >> 32); - nlh.filter_tag_bloom_lo = htonl(tag_bloom_bits & 0xffffffff); - } - - /* add properties list */ - nlh.properties_off = iov[0].iov_len; - nlh.properties_len = blen; - iov[1].iov_base = (char *)buf; - iov[1].iov_len = blen; - - memset(&smsg, 0x00, 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) - 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); - info(udev_monitor->udev, "passed %zi bytes to netlink monitor %p\n", count, udev_monitor); - return count; - } - - return -EINVAL; + const char *buf; + ssize_t blen; + ssize_t count; + + blen = udev_device_get_properties_monitor_buf(udev_device, &buf); + if (blen < 32) + return -EINVAL; + + if (udev_monitor->sun.sun_family != 0) { + struct msghdr smsg; + struct iovec iov[2]; + const char *action; + char header[2048]; + char *s; + + /* header @ */ + action = udev_device_get_action(udev_device); + if (action == NULL) + return -EINVAL; + s = header; + if (util_strpcpyl(&s, sizeof(header), action, "@", udev_device_get_devpath(udev_device), NULL) == 0) + return -EINVAL; + iov[0].iov_base = header; + iov[0].iov_len = (s - header)+1; + + /* add properties list */ + iov[1].iov_base = (char *)buf; + iov[1].iov_len = blen; + + memset(&smsg, 0x00, sizeof(struct msghdr)); + smsg.msg_iov = iov; + smsg.msg_iovlen = 2; + smsg.msg_name = &udev_monitor->sun; + smsg.msg_namelen = udev_monitor->addrlen; + count = sendmsg(udev_monitor->sock, &smsg, 0); + info(udev_monitor->udev, "passed %zi bytes to socket monitor %p\n", count, udev_monitor); + return count; + } + + if (udev_monitor->snl.nl_family != 0) { + struct msghdr smsg; + struct iovec iov[2]; + const char *val; + struct udev_monitor_netlink_header nlh; + struct udev_list_entry *list_entry; + uint64_t tag_bloom_bits; + + /* add versioned header */ + memset(&nlh, 0x00, 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); + 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; + udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device)) + tag_bloom_bits |= util_string_bloom64(udev_list_entry_get_name(list_entry)); + if (tag_bloom_bits > 0) { + nlh.filter_tag_bloom_hi = htonl(tag_bloom_bits >> 32); + nlh.filter_tag_bloom_lo = htonl(tag_bloom_bits & 0xffffffff); + } + + /* add properties list */ + nlh.properties_off = iov[0].iov_len; + nlh.properties_len = blen; + iov[1].iov_base = (char *)buf; + iov[1].iov_len = blen; + + memset(&smsg, 0x00, 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) + 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); + info(udev_monitor->udev, "passed %zi bytes to netlink monitor %p\n", count, udev_monitor); + return count; + } + + return -EINVAL; } /** @@ -826,13 +826,13 @@ int udev_monitor_send_device(struct udev_monitor *udev_monitor, */ UDEV_EXPORT int udev_monitor_filter_add_match_subsystem_devtype(struct udev_monitor *udev_monitor, const char *subsystem, const char *devtype) { - if (udev_monitor == NULL) - return -EINVAL; - if (subsystem == NULL) - return -EINVAL; - if (udev_list_entry_add(&udev_monitor->filter_subsystem_list, subsystem, devtype) == NULL) - return -ENOMEM; - return 0; + if (udev_monitor == NULL) + return -EINVAL; + if (subsystem == NULL) + return -EINVAL; + if (udev_list_entry_add(&udev_monitor->filter_subsystem_list, subsystem, devtype) == NULL) + return -ENOMEM; + return 0; } /** @@ -849,13 +849,13 @@ UDEV_EXPORT int udev_monitor_filter_add_match_subsystem_devtype(struct udev_moni */ UDEV_EXPORT int udev_monitor_filter_add_match_tag(struct udev_monitor *udev_monitor, const char *tag) { - if (udev_monitor == NULL) - return -EINVAL; - if (tag == NULL) - return -EINVAL; - if (udev_list_entry_add(&udev_monitor->filter_tag_list, tag, NULL) == NULL) - return -ENOMEM; - return 0; + if (udev_monitor == NULL) + return -EINVAL; + if (tag == NULL) + return -EINVAL; + if (udev_list_entry_add(&udev_monitor->filter_tag_list, tag, NULL) == NULL) + return -ENOMEM; + return 0; } /** @@ -868,8 +868,8 @@ UDEV_EXPORT int udev_monitor_filter_add_match_tag(struct udev_monitor *udev_moni */ UDEV_EXPORT int udev_monitor_filter_remove(struct udev_monitor *udev_monitor) { - static struct sock_fprog filter = { 0, NULL }; + static struct sock_fprog filter = { 0, NULL }; - udev_list_cleanup(&udev_monitor->filter_subsystem_list); - return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)); + udev_list_cleanup(&udev_monitor->filter_subsystem_list); + return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)); }