/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include #include #include "sd-device.h" #include "alloc-util.h" #include "chase.h" #include "device-internal.h" #include "device-private.h" #include "device-util.h" #include "devnum-util.h" #include "dirent-util.h" #include "env-util.h" #include "fd-util.h" #include "fileio.h" #include "format-util.h" #include "fs-util.h" #include "hashmap.h" #include "id128-util.h" #include "macro.h" #include "missing_magic.h" #include "netlink-util.h" #include "parse-util.h" #include "path-util.h" #include "set.h" #include "socket-util.h" #include "stdio-util.h" #include "string-util.h" #include "strv.h" #include "strxcpyx.h" #include "user-util.h" int device_new_aux(sd_device **ret) { sd_device *device; assert(ret); device = new(sd_device, 1); if (!device) return -ENOMEM; *device = (sd_device) { .n_ref = 1, .devmode = MODE_INVALID, .devuid = UID_INVALID, .devgid = GID_INVALID, .action = _SD_DEVICE_ACTION_INVALID, }; *ret = device; return 0; } static sd_device *device_free(sd_device *device) { assert(device); sd_device_unref(device->parent); free(device->syspath); free(device->sysname); free(device->devtype); free(device->devname); free(device->subsystem); free(device->driver_subsystem); free(device->driver); free(device->device_id); free(device->properties_strv); free(device->properties_nulstr); ordered_hashmap_free(device->properties); ordered_hashmap_free(device->properties_db); hashmap_free(device->sysattr_values); set_free(device->sysattrs); set_free(device->all_tags); set_free(device->current_tags); set_free(device->devlinks); hashmap_free(device->children); return mfree(device); } DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_device, sd_device, device_free); int device_add_property_aux(sd_device *device, const char *key, const char *value, bool db) { OrderedHashmap **properties; assert(device); assert(key); if (db) properties = &device->properties_db; else properties = &device->properties; if (value) { _unused_ _cleanup_free_ char *old_value = NULL; _cleanup_free_ char *new_key = NULL, *new_value = NULL, *old_key = NULL; int r; r = ordered_hashmap_ensure_allocated(properties, &string_hash_ops_free_free); if (r < 0) return r; new_key = strdup(key); if (!new_key) return -ENOMEM; new_value = strdup(value); if (!new_value) return -ENOMEM; old_value = ordered_hashmap_get2(*properties, key, (void**) &old_key); /* ordered_hashmap_replace() does not fail when the hashmap already has the entry. */ r = ordered_hashmap_replace(*properties, new_key, new_value); if (r < 0) return r; TAKE_PTR(new_key); TAKE_PTR(new_value); } else { _unused_ _cleanup_free_ char *old_value = NULL; _cleanup_free_ char *old_key = NULL; old_value = ordered_hashmap_remove2(*properties, key, (void**) &old_key); } if (!db) { device->properties_generation++; device->properties_buf_outdated = true; } return 0; } int device_set_syspath(sd_device *device, const char *_syspath, bool verify) { _cleanup_free_ char *syspath = NULL; const char *devpath; int r; assert(device); assert(_syspath); if (verify) { _cleanup_close_ int fd = -EBADF; /* The input path maybe a symlink located outside of /sys. Let's try to chase the symlink at first. * The primary use case is that e.g. /proc/device-tree is a symlink to /sys/firmware/devicetree/base. * By chasing symlinks in the path at first, we can call sd_device_new_from_path() with such path. */ r = chase(_syspath, NULL, 0, &syspath, &fd); if (r == -ENOENT) /* the device does not exist (any more?) */ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: Failed to chase symlinks in \"%s\".", _syspath); if (r < 0) return log_debug_errno(r, "sd-device: Failed to get target of '%s': %m", _syspath); if (!path_startswith(syspath, "/sys")) { _cleanup_free_ char *real_sys = NULL, *new_syspath = NULL; char *p; /* /sys is a symlink to somewhere sysfs is mounted on? In that case, we convert the path to real sysfs to "/sys". */ r = chase("/sys", NULL, 0, &real_sys, NULL); if (r < 0) return log_debug_errno(r, "sd-device: Failed to chase symlink /sys: %m"); p = path_startswith(syspath, real_sys); if (!p) return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: Canonicalized path '%s' does not starts with sysfs mount point '%s'", syspath, real_sys); new_syspath = path_join("/sys", p); if (!new_syspath) return log_oom_debug(); free_and_replace(syspath, new_syspath); path_simplify(syspath); } if (path_startswith(syspath, "/sys/devices/")) { /* For proper devices, stricter rules apply: they must have a 'uevent' file, * otherwise we won't allow them */ if (faccessat(fd, "uevent", F_OK, 0) < 0) { if (errno == ENOENT) /* This is not a valid device. Note, this condition is quite often * satisfied when enumerating devices or finding a parent device. * Hence, use log_trace_errno() here. */ return log_trace_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: the uevent file \"%s/uevent\" does not exist.", syspath); if (errno == ENOTDIR) /* Not actually a directory. */ return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: the syspath \"%s\" is not a directory.", syspath); return log_debug_errno(errno, "sd-device: cannot find uevent file for %s: %m", syspath); } } else { struct stat st; /* For everything else lax rules apply: they just need to be a directory */ if (fstat(fd, &st) < 0) return log_debug_errno(errno, "sd-device: failed to check if syspath \"%s\" is a directory: %m", syspath); if (!S_ISDIR(st.st_mode)) return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: the syspath \"%s\" is not a directory.", syspath); } /* Only operate on sysfs, i.e. refuse going down into /sys/fs/cgroup/ or similar places where * things are not arranged as kobjects in kernel, and hence don't necessarily have * kobject/attribute structure. */ r = getenv_bool_secure("SYSTEMD_DEVICE_VERIFY_SYSFS"); if (r < 0 && r != -ENXIO) log_debug_errno(r, "Failed to parse $SYSTEMD_DEVICE_VERIFY_SYSFS value: %m"); if (r != 0) { r = fd_is_fs_type(fd, SYSFS_MAGIC); if (r < 0) return log_debug_errno(r, "sd-device: failed to check if syspath \"%s\" is backed by sysfs.", syspath); if (r == 0) return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: the syspath \"%s\" is outside of sysfs, refusing.", syspath); } } else { /* must be a subdirectory of /sys */ if (!path_startswith(_syspath, "/sys/")) return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "sd-device: Syspath '%s' is not a subdirectory of /sys", _syspath); r = path_simplify_alloc(_syspath, &syspath); if (r < 0) return r; } assert_se(devpath = startswith(syspath, "/sys")); if (devpath[0] != '/') return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "sd-device: \"/sys\" alone is not a valid device path."); r = device_add_property_internal(device, "DEVPATH", devpath); if (r < 0) return log_debug_errno(r, "sd-device: Failed to add \"DEVPATH\" property for device \"%s\": %m", syspath); free_and_replace(device->syspath, syspath); device->devpath = devpath; /* Unset sysname and sysnum, they will be assigned when requested. */ device->sysnum = NULL; device->sysname = mfree(device->sysname); return 0; } static int device_new_from_syspath(sd_device **ret, const char *syspath, bool strict) { _cleanup_(sd_device_unrefp) sd_device *device = NULL; int r; assert_return(ret, -EINVAL); assert_return(syspath, -EINVAL); if (strict && !path_startswith(syspath, "/sys/")) return -EINVAL; r = device_new_aux(&device); if (r < 0) return r; r = device_set_syspath(device, syspath, /* verify= */ true); if (r < 0) return r; *ret = TAKE_PTR(device); return 0; } _public_ int sd_device_new_from_syspath(sd_device **ret, const char *syspath) { return device_new_from_syspath(ret, syspath, /* strict = */ true); } int device_new_from_mode_and_devnum(sd_device **ret, mode_t mode, dev_t devnum) { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; _cleanup_free_ char *syspath = NULL; const char *t; dev_t n; int r; assert(ret); if (S_ISCHR(mode)) t = "char"; else if (S_ISBLK(mode)) t = "block"; else return -ENOTTY; if (major(devnum) == 0) return -ENODEV; if (asprintf(&syspath, "/sys/dev/%s/" DEVNUM_FORMAT_STR, t, DEVNUM_FORMAT_VAL(devnum)) < 0) return -ENOMEM; r = sd_device_new_from_syspath(&dev, syspath); if (r < 0) return r; r = sd_device_get_devnum(dev, &n); if (r == -ENOENT) return -ENXIO; if (r < 0) return r; if (n != devnum) return -ENXIO; if (device_in_subsystem(dev, "block") != !!S_ISBLK(mode)) return -ENXIO; *ret = TAKE_PTR(dev); return 0; } _public_ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum) { assert_return(ret, -EINVAL); assert_return(IN_SET(type, 'b', 'c'), -EINVAL); return device_new_from_mode_and_devnum(ret, type == 'b' ? S_IFBLK : S_IFCHR, devnum); } static int device_new_from_main_ifname(sd_device **ret, const char *ifname) { const char *syspath; assert(ret); assert(ifname); syspath = strjoina("/sys/class/net/", ifname); return sd_device_new_from_syspath(ret, syspath); } _public_ int sd_device_new_from_ifname(sd_device **ret, const char *ifname) { _cleanup_free_ char *main_name = NULL; int r; assert_return(ret, -EINVAL); assert_return(ifname, -EINVAL); r = device_new_from_main_ifname(ret, ifname); if (r >= 0) return r; r = rtnl_resolve_ifname_full(NULL, RESOLVE_IFNAME_ALTERNATIVE | RESOLVE_IFNAME_NUMERIC, ifname, &main_name, NULL); if (r < 0) return r; return device_new_from_main_ifname(ret, main_name); } _public_ int sd_device_new_from_ifindex(sd_device **ret, int ifindex) { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; _cleanup_free_ char *ifname = NULL; int r, i; assert_return(ret, -EINVAL); assert_return(ifindex > 0, -EINVAL); r = rtnl_get_ifname_full(NULL, ifindex, &ifname, NULL); if (r < 0) return r; r = device_new_from_main_ifname(&dev, ifname); if (r < 0) return r; r = sd_device_get_ifindex(dev, &i); if (r == -ENOENT) return -ENXIO; if (r < 0) return r; if (i != ifindex) return -ENXIO; *ret = TAKE_PTR(dev); return 0; } static int device_strjoin_new( const char *a, const char *b, const char *c, const char *d, sd_device **ret) { const char *p; int r; p = strjoina(a, b, c, d); if (access(p, F_OK) < 0) return IN_SET(errno, ENOENT, ENAMETOOLONG) ? 0 : -errno; /* If this sysfs is too long then it doesn't exist either */ r = sd_device_new_from_syspath(ret, p); if (r < 0) return r; return 1; } _public_ int sd_device_new_from_subsystem_sysname( sd_device **ret, const char *subsystem, const char *sysname) { char *name; int r; assert_return(ret, -EINVAL); assert_return(subsystem, -EINVAL); assert_return(sysname, -EINVAL); if (!path_is_normalized(subsystem)) return -EINVAL; if (!path_is_normalized(sysname)) return -EINVAL; /* translate sysname back to sysfs filename */ name = strdupa_safe(sysname); string_replace_char(name, '/', '!'); if (streq(subsystem, "subsystem")) { FOREACH_STRING(s, "/sys/bus/", "/sys/class/") { r = device_strjoin_new(s, name, NULL, NULL, ret); if (r < 0) return r; if (r > 0) return 0; } } else if (streq(subsystem, "module")) { r = device_strjoin_new("/sys/module/", name, NULL, NULL, ret); if (r < 0) return r; if (r > 0) return 0; } else if (streq(subsystem, "drivers")) { const char *sep; sep = strchr(name, ':'); if (sep && sep[1] != '\0') { /* Require ":" and something non-empty after that. */ const char *subsys = memdupa_suffix0(name, sep - name); sep++; if (streq(sep, "drivers")) /* If the sysname is "drivers", then it's the drivers directory itself that is meant. */ r = device_strjoin_new("/sys/bus/", subsys, "/drivers", NULL, ret); else r = device_strjoin_new("/sys/bus/", subsys, "/drivers/", sep, ret); if (r < 0) return r; if (r > 0) return 0; } } r = device_strjoin_new("/sys/bus/", subsystem, "/devices/", name, ret); if (r < 0) return r; if (r > 0) return 0; r = device_strjoin_new("/sys/class/", subsystem, "/", name, ret); if (r < 0) return r; if (r > 0) return 0; r = device_strjoin_new("/sys/firmware/", subsystem, "/", name, ret); if (r < 0) return r; if (r > 0) return 0; return -ENODEV; } _public_ int sd_device_new_from_stat_rdev(sd_device **ret, const struct stat *st) { assert_return(ret, -EINVAL); assert_return(st, -EINVAL); return device_new_from_mode_and_devnum(ret, st->st_mode, st->st_rdev); } _public_ int sd_device_new_from_devname(sd_device **ret, const char *devname) { struct stat st; dev_t devnum; mode_t mode; assert_return(ret, -EINVAL); assert_return(devname, -EINVAL); /* This function actually accepts both devlinks and devnames, i.e. both symlinks and device * nodes below /dev/. */ /* Also ignore when the specified path is "/dev". */ if (isempty(path_startswith(devname, "/dev"))) return -EINVAL; if (device_path_parse_major_minor(devname, &mode, &devnum) >= 0) /* Let's shortcut when "/dev/block/maj:min" or "/dev/char/maj:min" is specified. * In that case, we can directly convert the path to syspath, hence it is not necessary * that the specified path exists. So, this works fine without udevd being running. */ return device_new_from_mode_and_devnum(ret, mode, devnum); if (stat(devname, &st) < 0) return ERRNO_IS_DEVICE_ABSENT(errno) ? -ENODEV : -errno; return sd_device_new_from_stat_rdev(ret, &st); } _public_ int sd_device_new_from_path(sd_device **ret, const char *path) { assert_return(ret, -EINVAL); assert_return(path, -EINVAL); if (path_startswith(path, "/dev")) return sd_device_new_from_devname(ret, path); return device_new_from_syspath(ret, path, /* strict = */ false); } int device_set_devtype(sd_device *device, const char *devtype) { _cleanup_free_ char *t = NULL; int r; assert(device); assert(devtype); t = strdup(devtype); if (!t) return -ENOMEM; r = device_add_property_internal(device, "DEVTYPE", t); if (r < 0) return r; return free_and_replace(device->devtype, t); } int device_set_ifindex(sd_device *device, const char *name) { int r, ifindex; assert(device); assert(name); ifindex = parse_ifindex(name); if (ifindex < 0) return ifindex; r = device_add_property_internal(device, "IFINDEX", name); if (r < 0) return r; device->ifindex = ifindex; return 0; } static int mangle_devname(const char *p, char **ret) { char *q; assert(p); assert(ret); if (!path_is_safe(p)) return -EINVAL; /* When the path is absolute, it must start with "/dev/", but ignore "/dev/" itself. */ if (path_is_absolute(p)) { if (isempty(path_startswith(p, "/dev/"))) return -EINVAL; q = strdup(p); } else q = path_join("/dev/", p); if (!q) return -ENOMEM; path_simplify(q); *ret = q; return 0; } int device_set_devname(sd_device *device, const char *devname) { _cleanup_free_ char *t = NULL; int r; assert(device); assert(devname); r = mangle_devname(devname, &t); if (r < 0) return r; r = device_add_property_internal(device, "DEVNAME", t); if (r < 0) return r; return free_and_replace(device->devname, t); } int device_set_devmode(sd_device *device, const char *_devmode) { unsigned devmode; int r; assert(device); assert(_devmode); r = safe_atou(_devmode, &devmode); if (r < 0) return r; if (devmode > 07777) return -EINVAL; r = device_add_property_internal(device, "DEVMODE", _devmode); if (r < 0) return r; device->devmode = devmode; return 0; } int device_set_devnum(sd_device *device, const char *major, const char *minor) { unsigned maj, min = 0; int r; assert(device); assert(major); r = safe_atou(major, &maj); if (r < 0) return r; if (maj == 0) return 0; if (!DEVICE_MAJOR_VALID(maj)) return -EINVAL; if (minor) { r = safe_atou(minor, &min); if (r < 0) return r; if (!DEVICE_MINOR_VALID(min)) return -EINVAL; } r = device_add_property_internal(device, "MAJOR", major); if (r < 0) return r; if (minor) { r = device_add_property_internal(device, "MINOR", minor); if (r < 0) return r; } device->devnum = makedev(maj, min); return 0; } int device_set_diskseq(sd_device *device, const char *str) { uint64_t diskseq; int r; assert(device); assert(str); r = safe_atou64(str, &diskseq); if (r < 0) return r; if (diskseq == 0) return -EINVAL; r = device_add_property_internal(device, "DISKSEQ", str); if (r < 0) return r; device->diskseq = diskseq; return 0; } static int handle_uevent_line( sd_device *device, const char *key, const char *value, const char **major, const char **minor) { assert(device); assert(key); assert(value); assert(major); assert(minor); if (streq(key, "DEVTYPE")) return device_set_devtype(device, value); if (streq(key, "IFINDEX")) return device_set_ifindex(device, value); if (streq(key, "DEVNAME")) return device_set_devname(device, value); if (streq(key, "DEVMODE")) return device_set_devmode(device, value); if (streq(key, "DISKSEQ")) return device_set_diskseq(device, value); if (streq(key, "MAJOR")) *major = value; else if (streq(key, "MINOR")) *minor = value; else return device_add_property_internal(device, key, value); return 0; } int device_read_uevent_file(sd_device *device) { _cleanup_free_ char *uevent = NULL; const char *syspath, *key = NULL, *value = NULL, *major = NULL, *minor = NULL; char *path; size_t uevent_len; int r; enum { PRE_KEY, KEY, PRE_VALUE, VALUE, INVALID_LINE, } state = PRE_KEY; assert(device); if (device->uevent_loaded || device->sealed) return 0; r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; device->uevent_loaded = true; path = strjoina(syspath, "/uevent"); r = read_full_virtual_file(path, &uevent, &uevent_len); if (r == -EACCES || ERRNO_IS_NEG_DEVICE_ABSENT(r)) /* The uevent files may be write-only, the device may be already removed, or the device * may not have the uevent file. */ return 0; if (r < 0) return log_device_debug_errno(device, r, "sd-device: Failed to read uevent file '%s': %m", path); for (size_t i = 0; i < uevent_len; i++) switch (state) { case PRE_KEY: if (!strchr(NEWLINE, uevent[i])) { key = &uevent[i]; state = KEY; } break; case KEY: if (uevent[i] == '=') { uevent[i] = '\0'; state = PRE_VALUE; } else if (strchr(NEWLINE, uevent[i])) { uevent[i] = '\0'; log_device_debug(device, "sd-device: Invalid uevent line '%s', ignoring", key); state = PRE_KEY; } break; case PRE_VALUE: value = &uevent[i]; state = VALUE; _fallthrough_; /* to handle empty property */ case VALUE: if (strchr(NEWLINE, uevent[i])) { uevent[i] = '\0'; r = handle_uevent_line(device, key, value, &major, &minor); if (r < 0) log_device_debug_errno(device, r, "sd-device: Failed to handle uevent entry '%s=%s', ignoring: %m", key, value); state = PRE_KEY; } break; default: assert_not_reached(); } if (major) { r = device_set_devnum(device, major, minor); if (r < 0) log_device_debug_errno(device, r, "sd-device: Failed to set 'MAJOR=%s' or 'MINOR=%s' from '%s', ignoring: %m", major, strna(minor), path); } return 0; } _public_ int sd_device_get_ifindex(sd_device *device, int *ifindex) { int r; assert_return(device, -EINVAL); r = device_read_uevent_file(device); if (r < 0) return r; if (device->ifindex <= 0) return -ENOENT; if (ifindex) *ifindex = device->ifindex; return 0; } _public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) { int r; assert_return(ret, -EINVAL); assert_return(id, -EINVAL); switch (id[0]) { case 'b': case 'c': { dev_t devt; if (isempty(id)) return -EINVAL; r = parse_devnum(id + 1, &devt); if (r < 0) return r; return sd_device_new_from_devnum(ret, id[0], devt); } case 'n': { int ifindex; ifindex = parse_ifindex(id + 1); if (ifindex < 0) return ifindex; return sd_device_new_from_ifindex(ret, ifindex); } case '+': { const char *subsys, *sep; sep = strchr(id + 1, ':'); if (!sep || sep - id - 1 > NAME_MAX) return -EINVAL; subsys = memdupa_suffix0(id + 1, sep - id - 1); return sd_device_new_from_subsystem_sysname(ret, subsys, sep + 1); } default: return -EINVAL; } } _public_ int sd_device_get_syspath(sd_device *device, const char **ret) { assert_return(device, -EINVAL); assert(path_startswith(device->syspath, "/sys/")); if (ret) *ret = device->syspath; return 0; } DEFINE_PRIVATE_HASH_OPS_FULL( device_by_path_hash_ops, char, path_hash_func, path_compare, free, sd_device, sd_device_unref); static int device_enumerate_children_internal(sd_device *device, const char *subdir, Set **stack, Hashmap **children) { _cleanup_closedir_ DIR *dir = NULL; int r; assert(device); assert(stack); assert(children); r = device_opendir(device, subdir, &dir); if (r < 0) return r; FOREACH_DIRENT_ALL(de, dir, return -errno) { _cleanup_(sd_device_unrefp) sd_device *child = NULL; _cleanup_free_ char *p = NULL; if (dot_or_dot_dot(de->d_name)) continue; if (!IN_SET(de->d_type, DT_LNK, DT_DIR)) continue; if (subdir) p = path_join(subdir, de->d_name); else p = strdup(de->d_name); if (!p) return -ENOMEM; /* Try to create child device. */ r = sd_device_new_child(&child, device, p); if (r >= 0) { /* OK, this is a child device, saving it. */ r = hashmap_ensure_put(children, &device_by_path_hash_ops, p, child); if (r < 0) return r; TAKE_PTR(p); TAKE_PTR(child); } else if (r == -ENODEV) { /* This is not a child device. Push the sub-directory into stack, and read it later. */ if (de->d_type == DT_LNK) /* Do not follow symlinks, otherwise, we will enter an infinite loop, e.g., * /sys/class/block/nvme0n1/subsystem/nvme0n1/subsystem/nvme0n1/subsystem/… */ continue; r = set_ensure_consume(stack, &path_hash_ops_free, TAKE_PTR(p)); if (r < 0) return r; } else return r; } return 0; } static int device_enumerate_children(sd_device *device) { _cleanup_hashmap_free_ Hashmap *children = NULL; _cleanup_set_free_ Set *stack = NULL; int r; assert(device); if (device->children_enumerated) return 0; /* Already enumerated. */ r = device_enumerate_children_internal(device, NULL, &stack, &children); if (r < 0) return r; for (;;) { _cleanup_free_ char *subdir = NULL; subdir = set_steal_first(stack); if (!subdir) break; r = device_enumerate_children_internal(device, subdir, &stack, &children); if (r < 0) return r; } device->children_enumerated = true; device->children = TAKE_PTR(children); return 1; /* Enumerated. */ } _public_ sd_device *sd_device_get_child_first(sd_device *device, const char **ret_suffix) { int r; assert(device); r = device_enumerate_children(device); if (r < 0) { log_device_debug_errno(device, r, "sd-device: failed to enumerate child devices: %m"); if (ret_suffix) *ret_suffix = NULL; return NULL; } device->children_iterator = ITERATOR_FIRST; return sd_device_get_child_next(device, ret_suffix); } _public_ sd_device *sd_device_get_child_next(sd_device *device, const char **ret_suffix) { sd_device *child; assert(device); (void) hashmap_iterate(device->children, &device->children_iterator, (void**) &child, (const void**) ret_suffix); return child; } _public_ int sd_device_new_child(sd_device **ret, sd_device *device, const char *suffix) { _cleanup_free_ char *path = NULL; sd_device *child; const char *s; int r; assert_return(ret, -EINVAL); assert_return(device, -EINVAL); assert_return(suffix, -EINVAL); if (!path_is_safe(suffix)) return -EINVAL; /* If we have already enumerated children, try to find the child from the cache. */ child = hashmap_get(device->children, suffix); if (child) { *ret = sd_device_ref(child); return 0; } r = sd_device_get_syspath(device, &s); if (r < 0) return r; path = path_join(s, suffix); if (!path) return -ENOMEM; return sd_device_new_from_syspath(ret, path); } static int device_new_from_child(sd_device **ret, sd_device *child) { _cleanup_free_ char *path = NULL; const char *syspath; int r; assert(ret); assert(child); r = sd_device_get_syspath(child, &syspath); if (r < 0) return r; for (;;) { _cleanup_free_ char *p = NULL; r = path_extract_directory(path ?: syspath, &p); if (r < 0) return r; if (path_equal(p, "/sys")) return -ENODEV; r = sd_device_new_from_syspath(ret, p); if (r != -ENODEV) return r; free_and_replace(path, p); } } _public_ int sd_device_get_parent(sd_device *child, sd_device **ret) { int r; assert_return(child, -EINVAL); if (!child->parent_set) { r = device_new_from_child(&child->parent, child); if (r < 0 && r != -ENODEV) return r; child->parent_set = true; } if (!child->parent) return -ENOENT; if (ret) *ret = child->parent; return 0; } int device_set_subsystem(sd_device *device, const char *subsystem) { _cleanup_free_ char *s = NULL; int r; assert(device); if (subsystem) { s = strdup(subsystem); if (!s) return -ENOMEM; } r = device_add_property_internal(device, "SUBSYSTEM", s); if (r < 0) return r; device->subsystem_set = true; return free_and_replace(device->subsystem, s); } int device_set_drivers_subsystem(sd_device *device) { _cleanup_free_ char *subsystem = NULL; const char *devpath, *drivers, *p; int r; assert(device); r = sd_device_get_devpath(device, &devpath); if (r < 0) return r; drivers = strstr(devpath, "/drivers/"); if (!drivers) drivers = endswith(devpath, "/drivers"); if (!drivers) return -EINVAL; /* Find the path component immediately before the "/drivers/" string */ r = path_find_last_component(devpath, /* accept_dot_dot= */ false, &drivers, &p); if (r < 0) return r; if (r == 0) return -EINVAL; subsystem = strndup(p, r); if (!subsystem) return -ENOMEM; r = device_set_subsystem(device, "drivers"); if (r < 0) return r; return free_and_replace(device->driver_subsystem, subsystem); } _public_ int sd_device_get_subsystem(sd_device *device, const char **ret) { int r; assert_return(device, -EINVAL); if (!device->subsystem_set) { _cleanup_free_ char *subsystem = NULL; const char *syspath; char *path; r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; /* read 'subsystem' link */ path = strjoina(syspath, "/subsystem"); r = readlink_value(path, &subsystem); if (r < 0 && r != -ENOENT) return log_device_debug_errno(device, r, "sd-device: Failed to read subsystem for %s: %m", device->devpath); if (subsystem) r = device_set_subsystem(device, subsystem); /* use implicit names */ else if (!isempty(path_startswith(device->devpath, "/module/"))) r = device_set_subsystem(device, "module"); else if (strstr(syspath, "/drivers/") || endswith(syspath, "/drivers")) r = device_set_drivers_subsystem(device); else if (!isempty(PATH_STARTSWITH_SET(device->devpath, "/class/", "/bus/"))) r = device_set_subsystem(device, "subsystem"); else { device->subsystem_set = true; r = 0; } if (r < 0) return log_device_debug_errno(device, r, "sd-device: Failed to set subsystem for %s: %m", device->devpath); } if (!device->subsystem) return -ENOENT; if (ret) *ret = device->subsystem; return 0; } _public_ int sd_device_get_devtype(sd_device *device, const char **devtype) { int r; assert_return(device, -EINVAL); r = device_read_uevent_file(device); if (r < 0) return r; if (!device->devtype) return -ENOENT; if (devtype) *devtype = device->devtype; return !!device->devtype; } _public_ int sd_device_get_parent_with_subsystem_devtype(sd_device *device, const char *subsystem, const char *devtype, sd_device **ret) { int r; assert_return(device, -EINVAL); assert_return(subsystem, -EINVAL); for (;;) { r = sd_device_get_parent(device, &device); if (r < 0) return r; if (!device_in_subsystem(device, subsystem)) continue; if (devtype && !device_is_devtype(device, devtype)) continue; if (ret) *ret = device; return 0; } } _public_ int sd_device_get_devnum(sd_device *device, dev_t *devnum) { int r; assert_return(device, -EINVAL); r = device_read_uevent_file(device); if (r < 0) return r; if (major(device->devnum) <= 0) return -ENOENT; if (devnum) *devnum = device->devnum; return 0; } int device_set_driver(sd_device *device, const char *driver) { _cleanup_free_ char *d = NULL; int r; assert(device); if (driver) { d = strdup(driver); if (!d) return -ENOMEM; } r = device_add_property_internal(device, "DRIVER", d); if (r < 0) return r; device->driver_set = true; return free_and_replace(device->driver, d); } _public_ int sd_device_get_driver(sd_device *device, const char **ret) { assert_return(device, -EINVAL); if (!device->driver_set) { _cleanup_free_ char *driver = NULL; const char *syspath; char *path; int r; r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; path = strjoina(syspath, "/driver"); r = readlink_value(path, &driver); if (r < 0 && r != -ENOENT) return log_device_debug_errno(device, r, "sd-device: readlink(\"%s\") failed: %m", path); r = device_set_driver(device, driver); if (r < 0) return log_device_debug_errno(device, r, "sd-device: Failed to set driver \"%s\": %m", driver); } if (!device->driver) return -ENOENT; if (ret) *ret = device->driver; return 0; } _public_ int sd_device_get_devpath(sd_device *device, const char **ret) { assert_return(device, -EINVAL); assert(device->devpath); assert(device->devpath[0] == '/'); if (ret) *ret = device->devpath; return 0; } _public_ int sd_device_get_devname(sd_device *device, const char **devname) { int r; assert_return(device, -EINVAL); r = device_read_uevent_file(device); if (r < 0) return r; if (!device->devname) return -ENOENT; assert(!isempty(path_startswith(device->devname, "/dev/"))); if (devname) *devname = device->devname; return 0; } static int device_set_sysname_and_sysnum(sd_device *device) { _cleanup_free_ char *sysname = NULL; size_t len, n; int r; assert(device); r = path_extract_filename(device->devpath, &sysname); if (r < 0) return r; if (r == O_DIRECTORY) return -EINVAL; /* some devices have '!' in their name, change that to '/' */ string_replace_char(sysname, '!', '/'); n = strspn_from_end(sysname, DIGITS); len = strlen(sysname); assert(n <= len); if (n == len) n = 0; /* Do not set sysnum for number only sysname. */ device->sysnum = n > 0 ? sysname + len - n : NULL; return free_and_replace(device->sysname, sysname); } _public_ int sd_device_get_sysname(sd_device *device, const char **ret) { int r; assert_return(device, -EINVAL); if (!device->sysname) { r = device_set_sysname_and_sysnum(device); if (r < 0) return r; } if (ret) *ret = device->sysname; return 0; } _public_ int sd_device_get_sysnum(sd_device *device, const char **ret) { int r; assert_return(device, -EINVAL); if (!device->sysname) { r = device_set_sysname_and_sysnum(device); if (r < 0) return r; } if (!device->sysnum) return -ENOENT; if (ret) *ret = device->sysnum; return 0; } _public_ int sd_device_get_action(sd_device *device, sd_device_action_t *ret) { assert_return(device, -EINVAL); if (device->action < 0) return -ENOENT; if (ret) *ret = device->action; return 0; } _public_ int sd_device_get_seqnum(sd_device *device, uint64_t *ret) { assert_return(device, -EINVAL); if (device->seqnum == 0) return -ENOENT; if (ret) *ret = device->seqnum; return 0; } _public_ int sd_device_get_diskseq(sd_device *device, uint64_t *ret) { int r; assert_return(device, -EINVAL); r = device_read_uevent_file(device); if (r < 0) return r; if (device->diskseq == 0) return -ENOENT; if (ret) *ret = device->diskseq; return 0; } static bool is_valid_tag(const char *tag) { assert(tag); return in_charset(tag, ALPHANUMERICAL "-_") && filename_is_valid(tag); } int device_add_tag(sd_device *device, const char *tag, bool both) { int r, added; assert(device); assert(tag); if (!is_valid_tag(tag)) return -EINVAL; /* Definitely add to the "all" list of tags (i.e. the sticky list) */ added = set_put_strdup(&device->all_tags, tag); if (added < 0) return added; /* And optionally, also add it to the current list of tags */ if (both) { r = set_put_strdup(&device->current_tags, tag); if (r < 0) { if (added > 0) (void) set_remove(device->all_tags, tag); return r; } } device->tags_generation++; device->property_tags_outdated = true; return 0; } int device_add_devlink(sd_device *device, const char *devlink) { char *p; int r; assert(device); assert(devlink); r = mangle_devname(devlink, &p); if (r < 0) return r; r = set_ensure_consume(&device->devlinks, &path_hash_ops_free, p); if (r < 0) return r; device->devlinks_generation++; device->property_devlinks_outdated = true; return r; /* return 1 when newly added, 0 when already exists */ } int device_remove_devlink(sd_device *device, const char *devlink) { _cleanup_free_ char *p = NULL, *s = NULL; int r; assert(device); assert(devlink); r = mangle_devname(devlink, &p); if (r < 0) return r; s = set_remove(device->devlinks, p); if (!s) return 0; /* does not exist */ device->devlinks_generation++; device->property_devlinks_outdated = true; return 1; /* removed */ } bool device_has_devlink(sd_device *device, const char *devlink) { assert(device); assert(devlink); return set_contains(device->devlinks, devlink); } static int device_add_property_internal_from_string(sd_device *device, const char *str) { _cleanup_free_ char *key = NULL; char *value; int r; assert(device); assert(str); key = strdup(str); if (!key) return -ENOMEM; value = strchr(key, '='); if (!value) return -EINVAL; *value = '\0'; if (isempty(++value)) value = NULL; /* Add the property to both sd_device::properties and sd_device::properties_db, * as this is called by only handle_db_line(). */ r = device_add_property_aux(device, key, value, false); if (r < 0) return r; return device_add_property_aux(device, key, value, true); } int device_set_usec_initialized(sd_device *device, usec_t when) { char s[DECIMAL_STR_MAX(usec_t)]; int r; assert(device); xsprintf(s, USEC_FMT, when); r = device_add_property_internal(device, "USEC_INITIALIZED", s); if (r < 0) return r; device->usec_initialized = when; return 0; } static int handle_db_line(sd_device *device, char key, const char *value) { int r; assert(device); assert(value); switch (key) { case 'G': /* Any tag */ case 'Q': /* Current tag */ return device_add_tag(device, value, key == 'Q'); case 'S': { const char *path; path = strjoina("/dev/", value); return device_add_devlink(device, path); } case 'E': return device_add_property_internal_from_string(device, value); case 'I': { usec_t t; r = safe_atou64(value, &t); if (r < 0) return r; return device_set_usec_initialized(device, t); } case 'L': return safe_atoi(value, &device->devlink_priority); case 'W': /* Deprecated. Previously, watch handle is both saved in database and /run/udev/watch. * However, the handle saved in database may not be updated when the handle is updated * or removed. Moreover, it is not necessary to store the handle within the database, * as its value becomes meaningless when udevd is restarted. */ return 0; case 'V': return safe_atou(value, &device->database_version); default: log_device_debug(device, "sd-device: Unknown key '%c' in device db, ignoring", key); return 0; } } int device_get_device_id(sd_device *device, const char **ret) { assert(device); assert(ret); if (!device->device_id) { _cleanup_free_ char *id = NULL; const char *subsystem; dev_t devnum; int ifindex, r; r = sd_device_get_subsystem(device, &subsystem); if (r < 0) return r; if (sd_device_get_devnum(device, &devnum) >= 0) { /* use dev_t — b259:131072, c254:0 */ if (asprintf(&id, "%c" DEVNUM_FORMAT_STR, streq(subsystem, "block") ? 'b' : 'c', DEVNUM_FORMAT_VAL(devnum)) < 0) return -ENOMEM; } else if (sd_device_get_ifindex(device, &ifindex) >= 0) { /* use netdev ifindex — n3 */ if (asprintf(&id, "n%u", (unsigned) ifindex) < 0) return -ENOMEM; } else { _cleanup_free_ char *sysname = NULL; /* use $subsys:$sysname — pci:0000:00:1f.2 * sd_device_get_sysname() has '!' translated, get it from devpath */ r = path_extract_filename(device->devpath, &sysname); if (r < 0) return r; if (r == O_DIRECTORY) return -EINVAL; if (streq(subsystem, "drivers")) { /* the 'drivers' pseudo-subsystem is special, and needs the real * subsystem encoded as well */ assert(device->driver_subsystem); id = strjoin("+drivers:", device->driver_subsystem, ":", sysname); } else id = strjoin("+", subsystem, ":", sysname); if (!id) return -ENOMEM; } if (!filename_is_valid(id)) return -EINVAL; device->device_id = TAKE_PTR(id); } *ret = device->device_id; return 0; } int device_read_db_internal_filename(sd_device *device, const char *filename) { _cleanup_free_ char *db = NULL; const char *value; size_t db_len; char key = '\0'; /* Unnecessary initialization to appease gcc-12.0.0-0.4.fc36 */ int r; enum { PRE_KEY, KEY, PRE_VALUE, VALUE, INVALID_LINE, } state = PRE_KEY; assert(device); assert(filename); r = read_full_file(filename, &db, &db_len); if (r < 0) { if (r == -ENOENT) return 0; return log_device_debug_errno(device, r, "sd-device: Failed to read db '%s': %m", filename); } /* devices with a database entry are initialized */ device->is_initialized = true; device->db_loaded = true; for (size_t i = 0; i < db_len; i++) switch (state) { case PRE_KEY: if (!strchr(NEWLINE, db[i])) { key = db[i]; state = KEY; } break; case KEY: if (db[i] != ':') { log_device_debug(device, "sd-device: Invalid db entry with key '%c', ignoring", key); state = INVALID_LINE; } else { db[i] = '\0'; state = PRE_VALUE; } break; case PRE_VALUE: value = &db[i]; state = VALUE; break; case INVALID_LINE: if (strchr(NEWLINE, db[i])) state = PRE_KEY; break; case VALUE: if (strchr(NEWLINE, db[i])) { db[i] = '\0'; r = handle_db_line(device, key, value); if (r < 0) log_device_debug_errno(device, r, "sd-device: Failed to handle db entry '%c:%s', ignoring: %m", key, value); state = PRE_KEY; } break; default: return log_device_debug_errno(device, SYNTHETIC_ERRNO(EINVAL), "sd-device: invalid db syntax."); } return 0; } _public_ int sd_device_get_is_initialized(sd_device *device) { int r; assert_return(device, -EINVAL); r = device_read_db(device); if (r == -ENOENT) /* The device may be already removed or renamed. */ return false; if (r < 0) return r; return device->is_initialized; } _public_ int sd_device_get_usec_initialized(sd_device *device, uint64_t *ret) { int r; assert_return(device, -EINVAL); r = sd_device_get_is_initialized(device); if (r < 0) return r; if (r == 0) return -EBUSY; if (device->usec_initialized == 0) return -ENODATA; if (ret) *ret = device->usec_initialized; return 0; } _public_ int sd_device_get_usec_since_initialized(sd_device *device, uint64_t *ret) { usec_t now_ts, ts; int r; assert_return(device, -EINVAL); r = sd_device_get_usec_initialized(device, &ts); if (r < 0) return r; now_ts = now(CLOCK_MONOTONIC); if (now_ts < ts) return -EIO; if (ret) *ret = usec_sub_unsigned(now_ts, ts); return 0; } _public_ const char *sd_device_get_tag_first(sd_device *device) { void *v; assert_return(device, NULL); (void) device_read_db(device); device->all_tags_iterator_generation = device->tags_generation; device->all_tags_iterator = ITERATOR_FIRST; (void) set_iterate(device->all_tags, &device->all_tags_iterator, &v); return v; } _public_ const char *sd_device_get_tag_next(sd_device *device) { void *v; assert_return(device, NULL); (void) device_read_db(device); if (device->all_tags_iterator_generation != device->tags_generation) return NULL; (void) set_iterate(device->all_tags, &device->all_tags_iterator, &v); return v; } static bool device_database_supports_current_tags(sd_device *device) { assert(device); (void) device_read_db(device); /* The current tags (saved in Q field) feature is implemented in database version 1. * If the database version is 0, then the tags (NOT current tags, saved in G field) are not * sticky. Thus, we can safely bypass the operations for the current tags (Q) to tags (G). */ return device->database_version >= 1; } _public_ const char *sd_device_get_current_tag_first(sd_device *device) { void *v; assert_return(device, NULL); if (!device_database_supports_current_tags(device)) return sd_device_get_tag_first(device); (void) device_read_db(device); device->current_tags_iterator_generation = device->tags_generation; device->current_tags_iterator = ITERATOR_FIRST; (void) set_iterate(device->current_tags, &device->current_tags_iterator, &v); return v; } _public_ const char *sd_device_get_current_tag_next(sd_device *device) { void *v; assert_return(device, NULL); if (!device_database_supports_current_tags(device)) return sd_device_get_tag_next(device); (void) device_read_db(device); if (device->current_tags_iterator_generation != device->tags_generation) return NULL; (void) set_iterate(device->current_tags, &device->current_tags_iterator, &v); return v; } _public_ const char *sd_device_get_devlink_first(sd_device *device) { void *v; assert_return(device, NULL); (void) device_read_db(device); device->devlinks_iterator_generation = device->devlinks_generation; device->devlinks_iterator = ITERATOR_FIRST; (void) set_iterate(device->devlinks, &device->devlinks_iterator, &v); return v; } _public_ const char *sd_device_get_devlink_next(sd_device *device) { void *v; assert_return(device, NULL); (void) device_read_db(device); if (device->devlinks_iterator_generation != device->devlinks_generation) return NULL; (void) set_iterate(device->devlinks, &device->devlinks_iterator, &v); return v; } int device_properties_prepare(sd_device *device) { int r; assert(device); r = device_read_uevent_file(device); if (r < 0) return r; r = device_read_db(device); if (r < 0) return r; if (device->property_devlinks_outdated) { _cleanup_free_ char *devlinks = NULL; r = set_strjoin(device->devlinks, " ", false, &devlinks); if (r < 0) return r; if (!isempty(devlinks)) { r = device_add_property_internal(device, "DEVLINKS", devlinks); if (r < 0) return r; } device->property_devlinks_outdated = false; } if (device->property_tags_outdated) { _cleanup_free_ char *tags = NULL; r = set_strjoin(device->all_tags, ":", true, &tags); if (r < 0) return r; if (!isempty(tags)) { r = device_add_property_internal(device, "TAGS", tags); if (r < 0) return r; } tags = mfree(tags); r = set_strjoin(device->current_tags, ":", true, &tags); if (r < 0) return r; if (!isempty(tags)) { r = device_add_property_internal(device, "CURRENT_TAGS", tags); if (r < 0) return r; } device->property_tags_outdated = false; } return 0; } _public_ const char *sd_device_get_property_first(sd_device *device, const char **_value) { const char *key; int r; assert_return(device, NULL); r = device_properties_prepare(device); if (r < 0) return NULL; device->properties_iterator_generation = device->properties_generation; device->properties_iterator = ITERATOR_FIRST; (void) ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)_value, (const void**)&key); return key; } _public_ const char *sd_device_get_property_next(sd_device *device, const char **_value) { const char *key; int r; assert_return(device, NULL); r = device_properties_prepare(device); if (r < 0) return NULL; if (device->properties_iterator_generation != device->properties_generation) return NULL; (void) ordered_hashmap_iterate(device->properties, &device->properties_iterator, (void**)_value, (const void**)&key); return key; } static int device_sysattrs_read_all_internal(sd_device *device, const char *subdir, Set **stack) { _cleanup_closedir_ DIR *dir = NULL; int r; assert(device); assert(stack); r = device_opendir(device, subdir, &dir); if (r == -ENOENT && subdir) return 0; /* Maybe, this is a child device, and is already removed. */ if (r < 0) return r; if (subdir) { if (faccessat(dirfd(dir), "uevent", F_OK, 0) >= 0) return 0; /* this is a child device, skipping */ if (errno != ENOENT) { log_device_debug_errno(device, errno, "sd-device: Failed to access %s/uevent, ignoring sub-directory %s: %m", subdir, subdir); return 0; } } FOREACH_DIRENT_ALL(de, dir, return -errno) { _cleanup_free_ char *p = NULL; struct stat statbuf; if (dot_or_dot_dot(de->d_name)) continue; /* only handle symlinks, regular files, and directories */ if (!IN_SET(de->d_type, DT_LNK, DT_REG, DT_DIR)) continue; if (subdir) { p = path_join(subdir, de->d_name); if (!p) return -ENOMEM; } if (de->d_type == DT_DIR) { /* push the sub-directory into the stack, and read it later. */ if (p) r = set_ensure_consume(stack, &path_hash_ops_free, TAKE_PTR(p)); else r = set_put_strdup_full(stack, &path_hash_ops_free, de->d_name); if (r < 0) return r; continue; } if (fstatat(dirfd(dir), de->d_name, &statbuf, AT_SYMLINK_NOFOLLOW) < 0) continue; if ((statbuf.st_mode & (S_IRUSR | S_IWUSR)) == 0) continue; if (p) r = set_ensure_consume(&device->sysattrs, &path_hash_ops_free, TAKE_PTR(p)); else r = set_put_strdup_full(&device->sysattrs, &path_hash_ops_free, de->d_name); if (r < 0) return r; } return 0; } static int device_sysattrs_read_all(sd_device *device) { _cleanup_set_free_ Set *stack = NULL; int r; assert(device); if (device->sysattrs_read) return 0; r = device_sysattrs_read_all_internal(device, NULL, &stack); if (r < 0) return r; for (;;) { _cleanup_free_ char *subdir = NULL; subdir = set_steal_first(stack); if (!subdir) break; r = device_sysattrs_read_all_internal(device, subdir, &stack); if (r < 0) return r; } device->sysattrs_read = true; return 0; } _public_ const char *sd_device_get_sysattr_first(sd_device *device) { void *v; int r; assert_return(device, NULL); if (!device->sysattrs_read) { r = device_sysattrs_read_all(device); if (r < 0) { errno = -r; return NULL; } } device->sysattrs_iterator = ITERATOR_FIRST; (void) set_iterate(device->sysattrs, &device->sysattrs_iterator, &v); return v; } _public_ const char *sd_device_get_sysattr_next(sd_device *device) { void *v; assert_return(device, NULL); if (!device->sysattrs_read) return NULL; (void) set_iterate(device->sysattrs, &device->sysattrs_iterator, &v); return v; } _public_ int sd_device_has_tag(sd_device *device, const char *tag) { assert_return(device, -EINVAL); assert_return(tag, -EINVAL); (void) device_read_db(device); return set_contains(device->all_tags, tag); } _public_ int sd_device_has_current_tag(sd_device *device, const char *tag) { assert_return(device, -EINVAL); assert_return(tag, -EINVAL); if (!device_database_supports_current_tags(device)) return sd_device_has_tag(device, tag); (void) device_read_db(device); return set_contains(device->current_tags, tag); } _public_ int sd_device_get_property_value(sd_device *device, const char *key, const char **ret_value) { const char *value; int r; assert_return(device, -EINVAL); assert_return(key, -EINVAL); r = device_properties_prepare(device); if (r < 0) return r; value = ordered_hashmap_get(device->properties, key); if (!value) return -ENOENT; if (ret_value) *ret_value = value; return 0; } int device_get_property_bool(sd_device *device, const char *key) { const char *value; int r; assert(device); assert(key); r = sd_device_get_property_value(device, key, &value); if (r < 0) return r; return parse_boolean(value); } int device_get_property_int(sd_device *device, const char *key, int *ret) { const char *value; int r, v; assert(device); assert(key); r = sd_device_get_property_value(device, key, &value); if (r < 0) return r; r = safe_atoi(value, &v); if (r < 0) return r; if (ret) *ret = v; return 0; } _public_ int sd_device_get_trigger_uuid(sd_device *device, sd_id128_t *ret) { const char *s; sd_id128_t id; int r; assert_return(device, -EINVAL); /* Retrieves the UUID attached to a uevent when triggering it from userspace via * sd_device_trigger_with_uuid() or an equivalent interface. Returns -ENOENT if the record is not * caused by a synthetic event and -ENODATA if it was but no UUID was specified */ r = sd_device_get_property_value(device, "SYNTH_UUID", &s); if (r < 0) return r; if (streq(s, "0")) /* SYNTH_UUID=0 is set whenever a device is triggered by userspace without specifying a UUID */ return -ENODATA; r = sd_id128_from_string(s, &id); if (r < 0) return r; if (ret) *ret = id; return 0; } void device_clear_sysattr_cache(sd_device *device) { device->sysattr_values = hashmap_free(device->sysattr_values); } int device_cache_sysattr_value(sd_device *device, const char *key, char *value) { _unused_ _cleanup_free_ char *old_value = NULL; _cleanup_free_ char *new_key = NULL; int r; assert(device); assert(key); /* This takes the reference of the input value. The input value may be NULL. * This replaces the value if it already exists. */ /* First, remove the old cache entry. So, we do not need to clear cache on error. */ old_value = hashmap_remove2(device->sysattr_values, key, (void **) &new_key); if (!new_key) { new_key = strdup(key); if (!new_key) return -ENOMEM; } r = hashmap_ensure_put(&device->sysattr_values, &path_hash_ops_free_free, new_key, value); if (r < 0) return r; TAKE_PTR(new_key); return 0; } int device_get_cached_sysattr_value(sd_device *device, const char *key, const char **ret_value) { const char *k = NULL, *value; assert(device); assert(key); value = hashmap_get2(device->sysattr_values, key, (void **) &k); if (!k) return -ESTALE; /* We have not read the attribute. */ if (!value) return -ENOENT; /* We have looked up the attribute before and it did not exist. */ if (ret_value) *ret_value = value; return 0; } /* We cache all sysattr lookups. If an attribute does not exist, it is stored * with a NULL value in the cache, otherwise the returned string is stored */ _public_ int sd_device_get_sysattr_value(sd_device *device, const char *sysattr, const char **ret_value) { _cleanup_free_ char *value = NULL, *path = NULL; const char *syspath; struct stat statbuf; int r; assert_return(device, -EINVAL); assert_return(sysattr, -EINVAL); /* look for possibly already cached result */ r = device_get_cached_sysattr_value(device, sysattr, ret_value); if (r != -ESTALE) return r; r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; path = path_join(syspath, sysattr); if (!path) return -ENOMEM; if (lstat(path, &statbuf) < 0) { int k; r = -errno; /* remember that we could not access the sysattr */ k = device_cache_sysattr_value(device, sysattr, NULL); if (k < 0) log_device_debug_errno(device, k, "sd-device: failed to cache attribute '%s' with NULL, ignoring: %m", sysattr); return r; } else if (S_ISLNK(statbuf.st_mode)) { /* Some core links return only the last element of the target path, * these are just values, the paths should not be exposed. */ if (STR_IN_SET(sysattr, "driver", "subsystem", "module")) { r = readlink_value(path, &value); if (r < 0) return r; } else return -EINVAL; } else if (S_ISDIR(statbuf.st_mode)) /* skip directories */ return -EISDIR; else if (!(statbuf.st_mode & S_IRUSR)) /* skip non-readable files */ return -EPERM; else { size_t size; /* Read attribute value, Some attributes contain embedded '\0'. So, it is necessary to * also get the size of the result. See issue #20025. */ r = read_full_virtual_file(path, &value, &size); if (r < 0) return r; /* drop trailing newlines */ while (size > 0 && strchr(NEWLINE, value[--size])) value[size] = '\0'; } /* Unfortunately, we need to return 'const char*' instead of 'char*'. Hence, failure in caching * sysattr value is critical unlike the other places. */ r = device_cache_sysattr_value(device, sysattr, value); if (r < 0) { log_device_debug_errno(device, r, "sd-device: failed to cache attribute '%s' with '%s'%s: %m", sysattr, value, ret_value ? "" : ", ignoring"); if (ret_value) return r; return 0; } if (ret_value) *ret_value = value; TAKE_PTR(value); return 0; } int device_get_sysattr_int(sd_device *device, const char *sysattr, int *ret_value) { const char *value; int r; r = sd_device_get_sysattr_value(device, sysattr, &value); if (r < 0) return r; int v; r = safe_atoi(value, &v); if (r < 0) return log_device_debug_errno(device, r, "Failed to parse '%s' attribute: %m", sysattr); if (ret_value) *ret_value = v; /* We return "true" if the value is positive. */ return v > 0; } int device_get_sysattr_unsigned(sd_device *device, const char *sysattr, unsigned *ret_value) { const char *value; int r; r = sd_device_get_sysattr_value(device, sysattr, &value); if (r < 0) return r; unsigned v; r = safe_atou(value, &v); if (r < 0) return log_device_debug_errno(device, r, "Failed to parse '%s' attribute: %m", sysattr); if (ret_value) *ret_value = v; /* We return "true" if the value is positive. */ return v > 0; } int device_get_sysattr_u32(sd_device *device, const char *sysattr, uint32_t *ret_value) { const char *value; int r; r = sd_device_get_sysattr_value(device, sysattr, &value); if (r < 0) return r; uint32_t v; r = safe_atou32(value, &v); if (r < 0) return log_device_debug_errno(device, r, "Failed to parse '%s' attribute: %m", sysattr); if (ret_value) *ret_value = v; /* We return "true" if the value is positive. */ return v > 0; } int device_get_sysattr_bool(sd_device *device, const char *sysattr) { const char *value; int r; assert(device); assert(sysattr); r = sd_device_get_sysattr_value(device, sysattr, &value); if (r < 0) return r; return parse_boolean(value); } static void device_remove_cached_sysattr_value(sd_device *device, const char *_key) { _cleanup_free_ char *key = NULL; assert(device); assert(_key); free(hashmap_remove2(device->sysattr_values, _key, (void **) &key)); } _public_ int sd_device_set_sysattr_value(sd_device *device, const char *sysattr, const char *_value) { _cleanup_free_ char *value = NULL, *path = NULL; const char *syspath; size_t len; int r; assert_return(device, -EINVAL); assert_return(sysattr, -EINVAL); /* Set the attribute and save it in the cache. */ if (!_value) { /* If input value is NULL, then clear cache and not write anything. */ device_remove_cached_sysattr_value(device, sysattr); return 0; } r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; path = path_join(syspath, sysattr); if (!path) return -ENOMEM; len = strlen(_value); /* drop trailing newlines */ while (len > 0 && strchr(NEWLINE, _value[len - 1])) len--; /* value length is limited to 4k */ if (len > 4096) return -EINVAL; value = strndup(_value, len); if (!value) return -ENOMEM; r = write_string_file(path, value, WRITE_STRING_FILE_DISABLE_BUFFER | WRITE_STRING_FILE_NOFOLLOW); if (r < 0) { /* On failure, clear cache entry, as we do not know how it fails. */ device_remove_cached_sysattr_value(device, sysattr); return r; } /* Do not cache action string written into uevent file. */ if (streq(sysattr, "uevent")) return 0; r = device_cache_sysattr_value(device, sysattr, value); if (r < 0) log_device_debug_errno(device, r, "sd-device: failed to cache attribute '%s' with '%s', ignoring: %m", sysattr, value); else TAKE_PTR(value); return 0; } _public_ int sd_device_set_sysattr_valuef(sd_device *device, const char *sysattr, const char *format, ...) { _cleanup_free_ char *value = NULL; va_list ap; int r; assert_return(device, -EINVAL); assert_return(sysattr, -EINVAL); if (!format) { device_remove_cached_sysattr_value(device, sysattr); return 0; } va_start(ap, format); r = vasprintf(&value, format, ap); va_end(ap); if (r < 0) return -ENOMEM; return sd_device_set_sysattr_value(device, sysattr, value); } _public_ int sd_device_trigger(sd_device *device, sd_device_action_t action) { const char *s; assert_return(device, -EINVAL); s = device_action_to_string(action); if (!s) return -EINVAL; /* This uses the simple no-UUID interface of kernel < 4.13 */ return sd_device_set_sysattr_value(device, "uevent", s); } _public_ int sd_device_trigger_with_uuid( sd_device *device, sd_device_action_t action, sd_id128_t *ret_uuid) { const char *s, *j; sd_id128_t u; int r; assert_return(device, -EINVAL); /* If no one wants to know the UUID, use the simple interface from pre-4.13 times */ if (!ret_uuid) return sd_device_trigger(device, action); s = device_action_to_string(action); if (!s) return -EINVAL; r = sd_id128_randomize(&u); if (r < 0) return r; j = strjoina(s, " ", SD_ID128_TO_UUID_STRING(u)); r = sd_device_set_sysattr_value(device, "uevent", j); if (r < 0) return r; *ret_uuid = u; return 0; } _public_ int sd_device_open(sd_device *device, int flags) { _cleanup_close_ int fd = -EBADF, fd2 = -EBADF; const char *devname; uint64_t q, diskseq = 0; struct stat st; dev_t devnum; int r; assert_return(device, -EINVAL); assert_return(FLAGS_SET(flags, O_PATH) || !FLAGS_SET(flags, O_NOFOLLOW), -EINVAL); r = sd_device_get_devname(device, &devname); if (r == -ENOENT) return -ENOEXEC; if (r < 0) return r; r = sd_device_get_devnum(device, &devnum); if (r == -ENOENT) return -ENOEXEC; if (r < 0) return r; fd = open(devname, FLAGS_SET(flags, O_PATH) ? flags : O_CLOEXEC|O_NOFOLLOW|O_PATH); if (fd < 0) return -errno; if (fstat(fd, &st) < 0) return -errno; if (st.st_rdev != devnum) return -ENXIO; if (device_in_subsystem(device, "block") ? !S_ISBLK(st.st_mode) : !S_ISCHR(st.st_mode)) return -ENXIO; /* If flags has O_PATH, then we cannot check diskseq. Let's return earlier. */ if (FLAGS_SET(flags, O_PATH)) return TAKE_FD(fd); /* If the device is not initialized, then we cannot determine if we should check diskseq through * ID_IGNORE_DISKSEQ property. Let's skip to check diskseq in that case. */ r = sd_device_get_is_initialized(device); if (r < 0) return r; if (r > 0) { r = device_get_property_bool(device, "ID_IGNORE_DISKSEQ"); if (r < 0 && r != -ENOENT) return r; if (r <= 0) { r = sd_device_get_diskseq(device, &diskseq); if (r < 0 && r != -ENOENT) return r; } } fd2 = fd_reopen(fd, flags); if (fd2 < 0) return fd2; if (diskseq == 0) return TAKE_FD(fd2); r = fd_get_diskseq(fd2, &q); if (r < 0) return r; if (q != diskseq) return -ENXIO; return TAKE_FD(fd2); } int device_opendir(sd_device *device, const char *subdir, DIR **ret) { _cleanup_closedir_ DIR *d = NULL; _cleanup_free_ char *path = NULL; const char *syspath; int r; assert(device); assert(ret); r = sd_device_get_syspath(device, &syspath); if (r < 0) return r; if (subdir) { if (!path_is_safe(subdir)) return -EINVAL; path = path_join(syspath, subdir); if (!path) return -ENOMEM; } d = opendir(path ?: syspath); if (!d) return -errno; *ret = TAKE_PTR(d); return 0; }