diff options
Diffstat (limited to 'src/libsystemd/sd-device/device-private.c')
-rw-r--r-- | src/libsystemd/sd-device/device-private.c | 903 |
1 files changed, 903 insertions, 0 deletions
diff --git a/src/libsystemd/sd-device/device-private.c b/src/libsystemd/sd-device/device-private.c new file mode 100644 index 0000000..0edabfb --- /dev/null +++ b/src/libsystemd/sd-device/device-private.c @@ -0,0 +1,903 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <ctype.h> +#include <net/if.h> +#include <sys/types.h> + +#include "sd-device.h" + +#include "alloc-util.h" +#include "device-internal.h" +#include "device-private.h" +#include "device-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "fs-util.h" +#include "hashmap.h" +#include "macro.h" +#include "mkdir.h" +#include "nulstr-util.h" +#include "parse-util.h" +#include "path-util.h" +#include "set.h" +#include "stdio-util.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "strxcpyx.h" +#include "tmpfile-util.h" +#include "user-util.h" + +int device_add_property(sd_device *device, const char *key, const char *value) { + int r; + + assert(device); + assert(key); + + r = device_add_property_aux(device, key, value, false); + if (r < 0) + return r; + + if (key[0] != '.') { + r = device_add_property_aux(device, key, value, true); + if (r < 0) + return r; + } + + return 0; +} + +int device_add_propertyf(sd_device *device, const char *key, const char *format, ...) { + _cleanup_free_ char *value = NULL; + va_list ap; + int r; + + assert(device); + assert(key); + + if (!format) + return device_add_property(device, key, NULL); + + va_start(ap, format); + r = vasprintf(&value, format, ap); + va_end(ap); + + if (r < 0) + return -ENOMEM; + + return device_add_property(device, key, value); +} + +void device_set_devlink_priority(sd_device *device, int priority) { + assert(device); + + device->devlink_priority = priority; +} + +void device_set_is_initialized(sd_device *device) { + assert(device); + + device->is_initialized = true; +} + +int device_ensure_usec_initialized(sd_device *device, sd_device *device_old) { + usec_t when; + + assert(device); + + if (device_old && device_old->usec_initialized > 0) + when = device_old->usec_initialized; + else + when = now(CLOCK_MONOTONIC); + + return device_set_usec_initialized(device, when); +} + +uint64_t device_get_properties_generation(sd_device *device) { + assert(device); + + return device->properties_generation; +} + +uint64_t device_get_tags_generation(sd_device *device) { + assert(device); + + return device->tags_generation; +} + +uint64_t device_get_devlinks_generation(sd_device *device) { + assert(device); + + return device->devlinks_generation; +} + +int device_get_devnode_mode(sd_device *device, mode_t *ret) { + int r; + + assert(device); + + r = device_read_db(device); + if (r < 0) + return r; + + if (device->devmode == MODE_INVALID) + return -ENOENT; + + if (ret) + *ret = device->devmode; + + return 0; +} + +int device_get_devnode_uid(sd_device *device, uid_t *ret) { + int r; + + assert(device); + + r = device_read_db(device); + if (r < 0) + return r; + + if (device->devuid == UID_INVALID) + return -ENOENT; + + if (ret) + *ret = device->devuid; + + return 0; +} + +static int device_set_devuid(sd_device *device, const char *uid) { + uid_t u; + int r; + + assert(device); + assert(uid); + + r = parse_uid(uid, &u); + if (r < 0) + return r; + + r = device_add_property_internal(device, "DEVUID", uid); + if (r < 0) + return r; + + device->devuid = u; + + return 0; +} + +int device_get_devnode_gid(sd_device *device, gid_t *ret) { + int r; + + assert(device); + + r = device_read_db(device); + if (r < 0) + return r; + + if (device->devgid == GID_INVALID) + return -ENOENT; + + if (ret) + *ret = device->devgid; + + return 0; +} + +static int device_set_devgid(sd_device *device, const char *gid) { + gid_t g; + int r; + + assert(device); + assert(gid); + + r = parse_gid(gid, &g); + if (r < 0) + return r; + + r = device_add_property_internal(device, "DEVGID", gid); + if (r < 0) + return r; + + device->devgid = g; + + return 0; +} + +int device_set_action(sd_device *device, sd_device_action_t a) { + int r; + + assert(device); + assert(a >= 0 && a < _SD_DEVICE_ACTION_MAX); + + r = device_add_property_internal(device, "ACTION", device_action_to_string(a)); + if (r < 0) + return r; + + device->action = a; + + return 0; +} + +static int device_set_action_from_string(sd_device *device, const char *action) { + sd_device_action_t a; + + assert(device); + assert(action); + + a = device_action_from_string(action); + if (a < 0) + return a; + + return device_set_action(device, a); +} + +static int device_set_seqnum(sd_device *device, const char *str) { + uint64_t seqnum; + int r; + + assert(device); + assert(str); + + r = safe_atou64(str, &seqnum); + if (r < 0) + return r; + if (seqnum == 0) + return -EINVAL; + + r = device_add_property_internal(device, "SEQNUM", str); + if (r < 0) + return r; + + device->seqnum = seqnum; + + return 0; +} + +static int device_amend(sd_device *device, const char *key, const char *value) { + int r; + + assert(device); + assert(key); + assert(value); + + if (streq(key, "DEVPATH")) { + char *path; + + path = strjoina("/sys", value); + + /* the caller must verify or trust this data (e.g., if it comes from the kernel) */ + r = device_set_syspath(device, path, false); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set syspath to '%s': %m", path); + } else if (streq(key, "SUBSYSTEM")) { + r = device_set_subsystem(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set subsystem to '%s': %m", value); + } else if (streq(key, "DEVTYPE")) { + r = device_set_devtype(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devtype to '%s': %m", value); + } else if (streq(key, "DEVNAME")) { + r = device_set_devname(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devname to '%s': %m", value); + } else if (streq(key, "USEC_INITIALIZED")) { + usec_t t; + + r = safe_atou64(value, &t); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to parse timestamp '%s': %m", value); + + r = device_set_usec_initialized(device, t); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set usec-initialized to '%s': %m", value); + } else if (streq(key, "DRIVER")) { + r = device_set_driver(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set driver to '%s': %m", value); + } else if (streq(key, "IFINDEX")) { + r = device_set_ifindex(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set ifindex to '%s': %m", value); + } else if (streq(key, "DEVMODE")) { + r = device_set_devmode(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devmode to '%s': %m", value); + } else if (streq(key, "DEVUID")) { + r = device_set_devuid(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devuid to '%s': %m", value); + } else if (streq(key, "DEVGID")) { + r = device_set_devgid(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devgid to '%s': %m", value); + } else if (streq(key, "ACTION")) { + r = device_set_action_from_string(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set action to '%s': %m", value); + } else if (streq(key, "SEQNUM")) { + r = device_set_seqnum(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set SEQNUM to '%s': %m", value); + } else if (streq(key, "DISKSEQ")) { + r = device_set_diskseq(device, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set DISKSEQ to '%s': %m", value); + } else if (streq(key, "DEVLINKS")) { + for (const char *p = value;;) { + _cleanup_free_ char *word = NULL; + + /* udev rules may set escaped strings, and sd-device does not modify the input + * strings. So, it is also necessary to keep the strings received through + * sd-device-monitor. */ + r = extract_first_word(&p, &word, NULL, EXTRACT_RETAIN_ESCAPE); + if (r < 0) + return r; + if (r == 0) + break; + + r = device_add_devlink(device, word); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to add devlink '%s': %m", word); + } + } else if (STR_IN_SET(key, "TAGS", "CURRENT_TAGS")) { + for (const char *p = value;;) { + _cleanup_free_ char *word = NULL; + + r = extract_first_word(&p, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS); + if (r < 0) + return r; + if (r == 0) + break; + if (isempty(word)) + continue; + + r = device_add_tag(device, word, streq(key, "CURRENT_TAGS")); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to add tag '%s': %m", word); + } + } else if (streq(key, "UDEV_DATABASE_VERSION")) { + r = safe_atou(value, &device->database_version); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to parse udev database version '%s': %m", value); + } else { + r = device_add_property_internal(device, key, value); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to add property '%s=%s': %m", key, value); + } + + return 0; +} + +static int device_append( + sd_device *device, + char *key, + const char **_major, + const char **_minor) { + + const char *major = NULL, *minor = NULL; + char *value; + int r; + + assert(device); + assert(key); + assert(_major); + assert(_minor); + + value = strchr(key, '='); + if (!value) + return log_device_debug_errno(device, SYNTHETIC_ERRNO(EINVAL), + "sd-device: Not a key-value pair: '%s'", key); + + *value = '\0'; + + value++; + + if (streq(key, "MAJOR")) + major = value; + else if (streq(key, "MINOR")) + minor = value; + else { + r = device_amend(device, key, value); + if (r < 0) + return r; + } + + if (major) + *_major = major; + + if (minor) + *_minor = minor; + + return 0; +} + +void device_seal(sd_device *device) { + assert(device); + + device->sealed = true; +} + +static int device_verify(sd_device *device) { + int r; + + assert(device); + + if (!device->devpath || !device->subsystem || device->action < 0 || device->seqnum == 0) + return log_device_debug_errno(device, SYNTHETIC_ERRNO(EINVAL), + "sd-device: Device created from strv or nulstr lacks devpath, subsystem, action or seqnum."); + + if (streq(device->subsystem, "drivers")) { + r = device_set_drivers_subsystem(device); + if (r < 0) + return r; + } + + device->sealed = true; + + return 0; +} + +int device_new_from_strv(sd_device **ret, char **strv) { + _cleanup_(sd_device_unrefp) sd_device *device = NULL; + const char *major = NULL, *minor = NULL; + int r; + + assert(ret); + assert(strv); + + r = device_new_aux(&device); + if (r < 0) + return r; + + STRV_FOREACH(key, strv) { + r = device_append(device, *key, &major, &minor); + if (r < 0) + return r; + } + + if (major) { + r = device_set_devnum(device, major, minor); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devnum %s:%s: %m", major, minor); + } + + r = device_verify(device); + if (r < 0) + return r; + + *ret = TAKE_PTR(device); + + return 0; +} + +int device_new_from_nulstr(sd_device **ret, char *nulstr, size_t len) { + _cleanup_(sd_device_unrefp) sd_device *device = NULL; + const char *major = NULL, *minor = NULL; + int r; + + assert(ret); + assert(nulstr); + assert(len); + + r = device_new_aux(&device); + if (r < 0) + return r; + + for (size_t i = 0; i < len; ) { + char *key; + const char *end; + + key = nulstr + i; + end = memchr(key, '\0', len - i); + if (!end) + return log_device_debug_errno(device, SYNTHETIC_ERRNO(EINVAL), + "sd-device: Failed to parse nulstr"); + + i += end - key + 1; + + /* netlink messages for some devices contain an unwanted newline at the end of value. + * Let's drop the newline and remaining characters after the newline. */ + truncate_nl(key); + + r = device_append(device, key, &major, &minor); + if (r < 0) + return r; + } + + if (major) { + r = device_set_devnum(device, major, minor); + if (r < 0) + return log_device_debug_errno(device, r, "sd-device: Failed to set devnum %s:%s: %m", major, minor); + } + + r = device_verify(device); + if (r < 0) + return r; + + *ret = TAKE_PTR(device); + + return 0; +} + +static int device_update_properties_bufs(sd_device *device) { + _cleanup_free_ char **buf_strv = NULL, *buf_nulstr = NULL; + size_t nulstr_len = 0, num = 0; + + assert(device); + + if (!device->properties_buf_outdated) + return 0; + + /* append udev database version */ + buf_nulstr = newdup(char, "UDEV_DATABASE_VERSION=" STRINGIFY(LATEST_UDEV_DATABASE_VERSION) "\0", + STRLEN("UDEV_DATABASE_VERSION=" STRINGIFY(LATEST_UDEV_DATABASE_VERSION)) + 2); + if (!buf_nulstr) + return -ENOMEM; + + nulstr_len += STRLEN("UDEV_DATABASE_VERSION=" STRINGIFY(LATEST_UDEV_DATABASE_VERSION)) + 1; + num++; + + FOREACH_DEVICE_PROPERTY(device, prop, val) { + size_t len = 0; + + len = strlen(prop) + 1 + strlen(val); + + buf_nulstr = GREEDY_REALLOC0(buf_nulstr, nulstr_len + len + 2); + if (!buf_nulstr) + return -ENOMEM; + + strscpyl(buf_nulstr + nulstr_len, len + 1, prop, "=", val, NULL); + nulstr_len += len + 1; + num++; + } + + /* build buf_strv from buf_nulstr */ + buf_strv = new0(char*, num + 1); + if (!buf_strv) + return -ENOMEM; + + size_t i = 0; + NULSTR_FOREACH(p, buf_nulstr) + buf_strv[i++] = p; + assert(i == num); + + free_and_replace(device->properties_nulstr, buf_nulstr); + device->properties_nulstr_len = nulstr_len; + free_and_replace(device->properties_strv, buf_strv); + + device->properties_buf_outdated = false; + return 0; +} + +int device_get_properties_nulstr(sd_device *device, const char **ret_nulstr, size_t *ret_len) { + int r; + + assert(device); + + r = device_update_properties_bufs(device); + if (r < 0) + return r; + + if (ret_nulstr) + *ret_nulstr = device->properties_nulstr; + if (ret_len) + *ret_len = device->properties_nulstr_len; + + return 0; +} + +int device_get_properties_strv(sd_device *device, char ***ret) { + int r; + + assert(device); + + r = device_update_properties_bufs(device); + if (r < 0) + return r; + + if (ret) + *ret = device->properties_strv; + + return 0; +} + +int device_get_devlink_priority(sd_device *device, int *ret) { + int r; + + assert(device); + + r = device_read_db(device); + if (r < 0) + return r; + + if (ret) + *ret = device->devlink_priority; + + return 0; +} + +int device_clone_with_db(sd_device *device, sd_device **ret) { + _cleanup_(sd_device_unrefp) sd_device *dest = NULL; + const char *key, *val; + int r; + + assert(device); + assert(ret); + + /* The device may be already removed. Let's copy minimal set of information that was obtained through + * netlink socket. */ + + r = device_new_aux(&dest); + if (r < 0) + return r; + + /* Seal device to prevent reading the uevent file, as the device may have been already removed. */ + dest->sealed = true; + + /* Copy syspath, then also devname, sysname or sysnum can be obtained. */ + r = device_set_syspath(dest, device->syspath, false); + if (r < 0) + return r; + + /* Copy other information stored in database. Here, do not use FOREACH_DEVICE_PROPERTY() and + * sd_device_get_property_value(), as they calls device_properties_prepare() -> + * device_read_uevent_file(), but as commented in the above, the device may be already removed and + * reading uevent file may fail. */ + ORDERED_HASHMAP_FOREACH_KEY(val, key, device->properties) { + if (streq(key, "MINOR")) + continue; + + if (streq(key, "MAJOR")) { + const char *minor = NULL; + + minor = ordered_hashmap_get(device->properties, "MINOR"); + r = device_set_devnum(dest, val, minor); + } else + r = device_amend(dest, key, val); + if (r < 0) + return r; + + if (streq(key, "SUBSYSTEM") && streq(val, "drivers")) { + r = free_and_strdup(&dest->driver_subsystem, device->driver_subsystem); + if (r < 0) + return r; + } + } + + /* Finally, read the udev database. */ + r = device_read_db_internal(dest, /* force = */ true); + if (r < 0) + return r; + + *ret = TAKE_PTR(dest); + return 0; +} + +void device_cleanup_tags(sd_device *device) { + assert(device); + + device->all_tags = set_free_free(device->all_tags); + device->current_tags = set_free_free(device->current_tags); + device->property_tags_outdated = true; + device->tags_generation++; +} + +void device_cleanup_devlinks(sd_device *device) { + assert(device); + + set_free_free(device->devlinks); + device->devlinks = NULL; + device->property_devlinks_outdated = true; + device->devlinks_generation++; +} + +void device_remove_tag(sd_device *device, const char *tag) { + assert(device); + assert(tag); + + free(set_remove(device->current_tags, tag)); + device->property_tags_outdated = true; + device->tags_generation++; +} + +static int device_tag(sd_device *device, const char *tag, bool add) { + const char *id; + char *path; + int r; + + assert(device); + assert(tag); + + r = device_get_device_id(device, &id); + if (r < 0) + return r; + + path = strjoina("/run/udev/tags/", tag, "/", id); + + if (add) + return touch_file(path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0444); + + if (unlink(path) < 0 && errno != ENOENT) + return -errno; + + return 0; +} + +int device_tag_index(sd_device *device, sd_device *device_old, bool add) { + int r = 0, k; + + if (add && device_old) + /* delete possible left-over tags */ + FOREACH_DEVICE_TAG(device_old, tag) + if (!sd_device_has_tag(device, tag)) { + k = device_tag(device_old, tag, false); + if (r >= 0 && k < 0) + r = k; + } + + FOREACH_DEVICE_TAG(device, tag) { + k = device_tag(device, tag, add); + if (r >= 0 && k < 0) + r = k; + } + + return r; +} + +static bool device_has_info(sd_device *device) { + assert(device); + + if (!set_isempty(device->devlinks)) + return true; + + if (device->devlink_priority != 0) + return true; + + if (!ordered_hashmap_isempty(device->properties_db)) + return true; + + if (!set_isempty(device->all_tags)) + return true; + + if (!set_isempty(device->current_tags)) + return true; + + return false; +} + +void device_set_db_persist(sd_device *device) { + assert(device); + + device->db_persist = true; +} + +int device_update_db(sd_device *device) { + const char *id; + char *path; + _cleanup_fclose_ FILE *f = NULL; + _cleanup_(unlink_and_freep) char *path_tmp = NULL; + bool has_info; + int r; + + assert(device); + + has_info = device_has_info(device); + + r = device_get_device_id(device, &id); + if (r < 0) + return r; + + path = strjoina("/run/udev/data/", id); + + /* do not store anything for otherwise empty devices */ + if (!has_info && major(device->devnum) == 0 && device->ifindex == 0) { + if (unlink(path) < 0 && errno != ENOENT) + return -errno; + + return 0; + } + + /* write a database file */ + r = mkdir_parents(path, 0755); + if (r < 0) + return r; + + r = fopen_temporary(path, &f, &path_tmp); + if (r < 0) + return r; + + /* set 'sticky' bit to indicate that we should not clean the database when we transition from initrd + * to the real root */ + if (fchmod(fileno(f), device->db_persist ? 01644 : 0644) < 0) { + r = -errno; + goto fail; + } + + if (has_info) { + const char *property, *value, *ct; + + if (major(device->devnum) > 0) { + FOREACH_DEVICE_DEVLINK(device, devlink) + fprintf(f, "S:%s\n", devlink + STRLEN("/dev/")); + + if (device->devlink_priority != 0) + fprintf(f, "L:%i\n", device->devlink_priority); + } + + if (device->usec_initialized > 0) + fprintf(f, "I:"USEC_FMT"\n", device->usec_initialized); + + ORDERED_HASHMAP_FOREACH_KEY(value, property, device->properties_db) + fprintf(f, "E:%s=%s\n", property, value); + + FOREACH_DEVICE_TAG(device, tag) + fprintf(f, "G:%s\n", tag); /* Any tag */ + + SET_FOREACH(ct, device->current_tags) + fprintf(f, "Q:%s\n", ct); /* Current tag */ + + /* Always write the latest database version here, instead of the value stored in + * device->database_version, as which may be 0. */ + fputs("V:" STRINGIFY(LATEST_UDEV_DATABASE_VERSION) "\n", f); + } + + r = fflush_and_check(f); + if (r < 0) + goto fail; + + if (rename(path_tmp, path) < 0) { + r = -errno; + goto fail; + } + + path_tmp = mfree(path_tmp); + + log_device_debug(device, "sd-device: Created %s file '%s' for '%s'", has_info ? "db" : "empty", + path, device->devpath); + + return 0; + +fail: + (void) unlink(path); + + return log_device_debug_errno(device, r, "sd-device: Failed to create %s file '%s' for '%s'", has_info ? "db" : "empty", path, device->devpath); +} + +int device_delete_db(sd_device *device) { + const char *id; + char *path; + int r; + + assert(device); + + r = device_get_device_id(device, &id); + if (r < 0) + return r; + + path = strjoina("/run/udev/data/", id); + + if (unlink(path) < 0 && errno != ENOENT) + return -errno; + + return 0; +} + +static const char* const device_action_table[_SD_DEVICE_ACTION_MAX] = { + [SD_DEVICE_ADD] = "add", + [SD_DEVICE_REMOVE] = "remove", + [SD_DEVICE_CHANGE] = "change", + [SD_DEVICE_MOVE] = "move", + [SD_DEVICE_ONLINE] = "online", + [SD_DEVICE_OFFLINE] = "offline", + [SD_DEVICE_BIND] = "bind", + [SD_DEVICE_UNBIND] = "unbind", +}; + +DEFINE_STRING_TABLE_LOOKUP(device_action, sd_device_action_t); + +void dump_device_action_table(void) { + DUMP_STRING_TABLE(device_action, sd_device_action_t, _SD_DEVICE_ACTION_MAX); +} |