device-private.c revision d854ba50a82f28b776c670d27156f0e9881fde8a
/***
This file is part of systemd.
Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
Copyright 2014 Tom Gundersen <teg@jklm.no>
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <ctype.h>
#include <sys/types.h>
#include <net/if.h>
#include "util.h"
#include "macro.h"
#include "refcnt.h"
#include "path-util.h"
#include "strxcpyx.h"
#include "fileio.h"
#include "hashmap.h"
#include "set.h"
#include "strv.h"
#include "mkdir.h"
#include "sd-device.h"
#include "device-util.h"
#include "device-internal.h"
#include "device-private.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;
}
static int device_add_property_internal_from_string(sd_device *device, const char *str) {
_cleanup_free_ char *key = NULL;
char *value;
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;
return device_add_property_internal(device, key, value);
}
static int handle_db_line(sd_device *device, char key, const char *value) {
char *path;
int r;
assert(device);
assert(value);
switch (key) {
case 'S':
path = strjoina("/dev/", value);
r = device_add_devlink(device, path);
if (r < 0)
return r;
break;
case 'L':
r = safe_atoi(value, &device->devlink_priority);
if (r < 0)
return r;
break;
case 'E':
r = device_add_property_internal_from_string(device, value);
if (r < 0)
return r;
break;
case 'G':
r = device_add_tag(device, value);
if (r < 0)
return r;
break;
case 'W':
r = safe_atoi(value, &device->watch_handle);
if (r < 0)
return r;
break;
case 'I':
r = device_set_usec_initialized(device, value);
if (r < 0)
return r;
break;
default:
log_debug("device db: unknown key '%c'", key);
}
return 0;
}
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) {
char num[DECIMAL_STR_MAX(usec_t)];
usec_t usec_initialized;
int r;
assert(device);
if (device_old && device_old->usec_initialized > 0)
usec_initialized = device_old->usec_initialized;
else
usec_initialized = now(CLOCK_MONOTONIC);
r = snprintf(num, sizeof(num), USEC_FMT, usec_initialized);
if (r < 0)
return -errno;
r = device_set_usec_initialized(device, num);
if (r < 0)
return r;
return 0;
}
static int device_read_db(sd_device *device) {
_cleanup_free_ char *db = NULL;
char *path;
const char *id, *value;
char key;
size_t db_len;
unsigned i;
int r;
enum {
PRE_KEY,
KEY,
PRE_VALUE,
VALUE,
INVALID_LINE,
} state = PRE_KEY;
assert(device);
if (device->db_loaded || device->sealed)
return 0;
r = device_get_id_filename(device, &id);
if (r < 0)
return r;
path = strjoina("/run/udev/data/", id);
r = read_full_file(path, &db, &db_len);
if (r < 0) {
if (r == -ENOENT)
return 0;
else {
log_debug("sd-device: failed to read db '%s': %s", path, strerror(-r));
return r;
}
}
/* devices with a database entry are initialized */
device_set_is_initialized(device);
for (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_debug("sd-device: ignoring invalid db entry with key '%c'", 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_debug("sd-device: failed to handle db entry '%c:%s': %s", key, value, strerror(-r));
state = PRE_KEY;
}
break;
default:
assert_not_reached("invalid state when parsing db");
}
}
device->db_loaded = true;
return 0;
}
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 *mode) {
int r;
assert(device);
assert(mode);
r = device_read_db(device);
if (r < 0)
return r;
*mode = device->devmode;
return 0;
}
int device_get_devnode_uid(sd_device *device, uid_t *uid) {
int r;
assert(device);
assert(uid);
r = device_read_db(device);
if (r < 0)
return r;
*uid = device->devuid;
return 0;
}
static int device_set_devuid(sd_device *device, const char *uid) {
unsigned u;
int r;
assert(device);
assert(uid);
r = safe_atou(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 *gid) {
int r;
assert(device);
assert(gid);
r = device_read_db(device);
if (r < 0)
return r;
*gid = device->devgid;
return 0;
}
static int device_set_devgid(sd_device *device, const char *gid) {
unsigned g;
int r;
assert(device);
assert(gid);
r = safe_atou(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;
}
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_debug_errno(r, "sd-device: could not set syspath to '%s': %m", path);
} else if (streq(key, "SUBSYSTEM")) {
r = device_set_subsystem(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set subsystem to '%s': %m", value);
} else if (streq(key, "DEVTYPE")) {
r = device_set_devtype(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devtype to '%s': %m", value);
} else if (streq(key, "DEVNAME")) {
r = device_set_devname(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devname to '%s': %m", value);
} else if (streq(key, "USEC_INITIALIZED")) {
r = device_set_usec_initialized(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set usec-initialized to '%s': %m", value);
} else if (streq(key, "DRIVER")) {
r = device_set_driver(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set driver to '%s': %m", value);
} else if (streq(key, "IFINDEX")) {
r = device_set_ifindex(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set ifindex to '%s': %m", value);
} else if (streq(key, "DEVMODE")) {
r = device_set_devmode(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devmode to '%s': %m", value);
} else if (streq(key, "DEVUID")) {
r = device_set_devuid(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devuid to '%s': %m", value);
} else if (streq(key, "DEVGID")) {
r = device_set_devgid(device, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devgid to '%s': %m", value);
} else if (streq(key, "DEVLINKS")) {
const char *word, *state;
size_t l;
FOREACH_WORD(word, l, value, state) {
char devlink[l + 1];
strncpy(devlink, word, l);
devlink[l] = '\0';
r = device_add_devlink(device, devlink);
if (r < 0)
return log_debug_errno(r, "sd-device: could not add devlink '%s': %m", devlink);
}
} else if (streq(key, "TAGS")) {
const char *word, *state;
size_t l;
FOREACH_WORD_SEPARATOR(word, l, value, ":", state) {
char tag[l + 1];
(void)strncpy(tag, word, l);
tag[l] = '\0';
r = device_add_tag(device, tag);
if (r < 0)
return log_debug_errno(r, "sd-device: could not add tag '%s': %m", tag);
}
} else {
r = device_add_property_internal(device, key, value);
if (r < 0)
return log_debug_errno(r, "sd-device: could not add property '%s=%s': %m", key, value);
}
return 0;
}
static const char* const device_action_table[_DEVICE_ACTION_MAX] = {
[DEVICE_ACTION_ADD] = "add",
[DEVICE_ACTION_REMOVE] = "remove",
[DEVICE_ACTION_CHANGE] = "change",
[DEVICE_ACTION_MOVE] = "move",
[DEVICE_ACTION_ONLINE] = "online",
[DEVICE_ACTION_OFFLINE] = "offline",
};
DEFINE_STRING_TABLE_LOOKUP(device_action, DeviceAction);
static int device_append(sd_device *device, char *key, const char **_major, const char **_minor, uint64_t *_seqnum,
DeviceAction *_action) {
DeviceAction action = _DEVICE_ACTION_INVALID;
uint64_t seqnum = 0;
const char *major = NULL, *minor = NULL;
char *value;
int r;
assert(device);
assert(key);
assert(_major);
assert(_minor);
assert(_seqnum);
assert(_action);
value = strchr(key, '=');
if (!value) {
log_debug("sd-device: not a key-value pair: '%s'", key);
return -EINVAL;
}
*value = '\0';
value++;
if (streq(key, "MAJOR"))
major = value;
else if (streq(key, "MINOR"))
minor = value;
else {
if (streq(key, "ACTION")) {
action = device_action_from_string(value);
if (action == _DEVICE_ACTION_INVALID)
return -EINVAL;
} else if (streq(key, "SEQNUM")) {
r = safe_atou64(value, &seqnum);
if (r < 0)
return r;
else if (seqnum == 0)
/* kernel only sends seqnum > 0 */
return -EINVAL;
}
r = device_amend(device, key, value);
if (r < 0)
return r;
}
if (major != 0)
*_major = major;
if (minor != 0)
*_minor = minor;
if (action != _DEVICE_ACTION_INVALID)
*_action = action;
if (seqnum > 0)
*_seqnum = seqnum;
return 0;
}
void device_seal(sd_device *device) {
assert(device);
device->sealed = true;
}
static int device_verify(sd_device *device, DeviceAction action, uint64_t seqnum) {
assert(device);
if (!device->devpath || !device->subsystem || action == _DEVICE_ACTION_INVALID || seqnum == 0) {
log_debug("sd-device: device created from strv lacks devpath, subsystem, action or seqnum");
return -EINVAL;
}
device->sealed = true;
return 0;
}
int device_new_from_strv(sd_device **ret, char **strv) {
_cleanup_device_unref_ sd_device *device = NULL;
char **key;
const char *major = NULL, *minor = NULL;
DeviceAction action = _DEVICE_ACTION_INVALID;
uint64_t seqnum;
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, &seqnum, &action);
if (r < 0)
return r;
}
if (major) {
r = device_set_devnum(device, major, minor);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devnum %s:%s: %m", major, minor);
}
r = device_verify(device, action, seqnum);
if (r < 0)
return r;
*ret = device;
device = NULL;
return 0;
}
int device_new_from_nulstr(sd_device **ret, uint8_t *nulstr, size_t len) {
_cleanup_device_unref_ sd_device *device = NULL;
const char *major = NULL, *minor = NULL;
DeviceAction action = _DEVICE_ACTION_INVALID;
uint64_t seqnum;
unsigned i = 0;
int r;
assert(ret);
assert(nulstr);
assert(len);
r = device_new_aux(&device);
if (r < 0)
return r;
while (i < len) {
char *key;
const char *end;
key = (char*)&nulstr[i];
end = memchr(key, '\0', len - i);
if (!end) {
log_debug("sd-device: failed to parse nulstr");
return -EINVAL;
}
i += end - key + 1;
r = device_append(device, key, &major, &minor, &seqnum, &action);
if (r < 0)
return r;
}
if (major) {
r = device_set_devnum(device, major, minor);
if (r < 0)
return log_debug_errno(r, "sd-device: could not set devnum %s:%s: %m", major, minor);
}
r = device_verify(device, action, seqnum);
if (r < 0)
return r;
*ret = device;
device = NULL;
return 0;
}
static int device_update_properties_bufs(sd_device *device) {
const char *val, *prop;
uint8_t *buf_nulstr = NULL;
size_t allocated_nulstr = 0;
size_t nulstr_len = 0, num = 0, i;
assert(device);
if (!device->properties_buf_outdated)
return 0;
FOREACH_DEVICE_PROPERTY(device, prop, val) {
size_t len = 0;
len = strlen(prop) + 1 + strlen(val);
buf_nulstr = GREEDY_REALLOC0(buf_nulstr, allocated_nulstr, nulstr_len + len + 2);
if (!buf_nulstr)
return -ENOMEM;
strscpyl((char *)buf_nulstr + nulstr_len, len + 1, prop, "=", val, NULL);
nulstr_len += len + 1;
++num;
}
free(device->properties_nulstr);
device->properties_nulstr = buf_nulstr;
device->properties_nulstr_len = nulstr_len;
/* build strv from buf_nulstr */
free(device->properties_strv);
device->properties_strv = new0(char *, num + 1);
i = 0;
NULSTR_FOREACH(val, (char*) buf_nulstr) {
device->properties_strv[i] = (char *) val;
assert(i < num);
i++;
}
device->properties_buf_outdated = false;
return 0;
}
int device_get_properties_nulstr(sd_device *device, const uint8_t **nulstr, size_t *len) {
int r;
assert(device);
assert(nulstr);
assert(len);
r = device_update_properties_bufs(device);
if (r < 0)
return r;
*nulstr = device->properties_nulstr;
*len = device->properties_nulstr_len;
return 0;
}
int device_get_properties_strv(sd_device *device, char ***strv) {
int r;
assert(device);
assert(strv);
r = device_update_properties_bufs(device);
if (r < 0)
return r;
*strv = device->properties_strv;
return 0;
}
int device_get_devlink_priority(sd_device *device, int *priority) {
int r;
assert(device);
assert(priority);
r = device_read_db(device);
if (r < 0)
return r;
*priority = device->devlink_priority;
return 0;
}
int device_get_watch_handle(sd_device *device, int *handle) {
int r;
assert(device);
assert(handle);
r = device_read_db(device);
if (r < 0)
return r;
*handle = device->watch_handle;
return 0;
}
void device_set_watch_handle(sd_device *device, int handle) {
assert(device);
device->watch_handle = handle;
}
int device_rename(sd_device *device, const char *name) {
_cleanup_free_ char *dirname = NULL;
char *new_syspath;
const char *interface;
int r;
assert(device);
assert(name);
dirname = dirname_malloc(device->syspath);
if (!dirname)
return -ENOMEM;
new_syspath = strjoina(dirname, "/", name);
/* the user must trust that the new name is correct */
r = device_set_syspath(device, new_syspath, false);
if (r < 0)
return r;
r = sd_device_get_property_value(device, "INTERFACE", &interface);
if (r >= 0) {
r = device_add_property_internal(device, "INTERFACE", name);
if (r < 0)
return r;
/* like DEVPATH_OLD, INTERFACE_OLD is not saved to the db, but only stays around for the current event */
r = device_add_property_internal(device, "INTERFACE_OLD", interface);
if (r < 0)
return r;
} else if (r != -ENOENT)
return r;
return 0;
}
int device_shallow_clone(sd_device *old_device, sd_device **new_device) {
_cleanup_device_unref_ sd_device *ret = NULL;
int r;
assert(old_device);
assert(new_device);
r = device_new_aux(&ret);
if (r < 0)
return r;
r = device_set_syspath(ret, old_device->syspath, false);
if (r < 0)
return r;
r = device_set_subsystem(ret, old_device->subsystem);
if (r < 0)
return r;
ret->devnum = old_device->devnum;
*new_device = ret;
ret = NULL;
return 0;
}
int device_clone_with_db(sd_device *old_device, sd_device **new_device) {
_cleanup_device_unref_ sd_device *ret = NULL;
int r;
assert(old_device);
assert(new_device);
r = device_shallow_clone(old_device, &ret);
if (r < 0)
return r;
r = device_read_db(ret);
if (r < 0)
return r;
ret->sealed = true;
*new_device = ret;
ret = NULL;
return 0;
}
int device_new_from_synthetic_event(sd_device **new_device, const char *syspath, const char *action) {
_cleanup_device_unref_ sd_device *ret = NULL;
int r;
assert(new_device);
assert(syspath);
assert(action);
r = sd_device_new_from_syspath(&ret, syspath);
if (r < 0)
return r;
r = device_read_uevent_file(ret);
if (r < 0)
return r;
r = device_add_property_internal(ret, "ACTION", action);
if (r < 0)
return r;
*new_device = ret;
ret = NULL;
return 0;
}
int device_copy_properties(sd_device *device_dst, sd_device *device_src) {
const char *property, *value;
int r;
assert(device_dst);
assert(device_src);
FOREACH_DEVICE_PROPERTY(device_src, property, value) {
r = device_add_property(device_dst, property, value);
if (r < 0)
return r;
}
return 0;
}
void device_cleanup_tags(sd_device *device) {
assert(device);
set_free_free(device->tags);
device->tags = NULL;
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->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_id_filename(device, &id);
if (r < 0)
return r;
path = strjoina("/run/udev/tags/", tag, "/", id);
if (add) {
r = touch_file(path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0444);
if (r < 0)
return r;
} else {
r = unlink(path);
if (r < 0 && errno != ENOENT)
return -errno;
}
return 0;
}
int device_tag_index(sd_device *device, sd_device *device_old, bool add) {
const char *tag;
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->tags))
return true;
if (device->watch_handle >= 0)
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_free_ char *path_tmp = NULL;
bool has_info;
int r;
assert(device);
has_info = device_has_info(device);
r = device_get_id_filename(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) {
r = unlink(path);
if (r < 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 initramfs to the real root
*/
if (device->db_persist) {
r = fchmod(fileno(f), 01644);
if (r < 0) {
r = -errno;
goto fail;
}
} else {
r = fchmod(fileno(f), 0644);
if (r < 0) {
r = -errno;
goto fail;
}
}
if (has_info) {
const char *property, *value, *tag;
Iterator i;
if (major(device->devnum) > 0) {
const char *devlink;
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->watch_handle >= 0)
fprintf(f, "W:%i\n", device->watch_handle);
}
if (device->usec_initialized > 0)
fprintf(f, "I:"USEC_FMT"\n", device->usec_initialized);
ORDERED_HASHMAP_FOREACH_KEY(value, property, device->properties_db, i)
fprintf(f, "E:%s=%s\n", property, value);
FOREACH_DEVICE_TAG(device, tag)
fprintf(f, "G:%s\n", tag);
}
r = fflush_and_check(f);
if (r < 0)
goto fail;
r = rename(path_tmp, path);
if (r < 0) {
r = -errno;
goto fail;
}
log_debug("created %s file '%s' for '%s'", has_info ? "db" : "empty",
path, device->devpath);
return 0;
fail:
log_error_errno(r, "failed to create %s file '%s' for '%s'", has_info ? "db" : "empty",
path, device->devpath);
unlink(path);
unlink(path_tmp);
return r;
}
int device_delete_db(sd_device *device) {
const char *id;
char *path;
int r;
assert(device);
r = device_get_id_filename(device, &id);
if (r < 0)
return r;
path = strjoina("/run/udev/data/", id);
r = unlink(path);
if (r < 0 && errno != ENOENT)
return -errno;
return 0;
}
int device_read_db_force(sd_device *device) {
assert(device);
return device_read_db_aux(device, true);
}