Files
cryptsetup/lib/luks2/luks2_json_metadata.c
2017-09-27 10:18:38 +02:00

1819 lines
48 KiB
C

/*
* LUKS - Linux Unified Key Setup v2
*
* Copyright (C) 2015-2017, Red Hat, Inc. All rights reserved.
* Copyright (C) 2015-2017, Milan Broz. All rights reserved.
* Copyright (C) 2015-2017, Ondrej Kozina. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "luks2_internal.h"
#include "../integrity/integrity.h"
#include <assert.h>
#include <ctype.h>
#include <uuid/uuid.h>
struct interval {
uint64_t offset;
uint64_t length;
};
void hexprint_base64(struct crypt_device *cd, json_object *jobj,
const char *sep, const char *line_sep)
{
char *buf = NULL;
size_t buf_len;
unsigned int i;
if (!base64_decode_alloc(json_object_get_string(jobj),
json_object_get_string_len(jobj),
&buf, &buf_len))
return;
for (i = 0; i < buf_len / 2; i++)
log_std(cd, "%02hhx%s", buf[i], sep);
log_std(cd, "\n\t%s", line_sep);
for (i = buf_len / 2; i < buf_len; i++)
log_std(cd, "%02hhx%s", buf[i], sep);
log_std(cd, "\n");
free(buf);
}
void JSON_DBG(json_object *jobj, const char *desc)
{
/* FIXME: make this conditional and disable for stable release. */
if (desc)
log_dbg("%s:", desc);
log_dbg("%s", json_object_to_json_string_ext(jobj, JSON_C_TO_STRING_PRETTY));
}
/*
* JSON array helpers
*/
struct json_object *LUKS2_array_jobj(struct json_object *array, const char *num)
{
struct json_object *jobj1;
int i;
for (i = 0; i < json_object_array_length(array); i++) {
jobj1 = json_object_array_get_idx(array, i);
if (!strcmp(num, json_object_get_string(jobj1)))
return jobj1;
}
return NULL;
}
struct json_object *LUKS2_array_remove(struct json_object *array, const char *num)
{
struct json_object *jobj1, *jobj_removing = NULL, *array_new;
int i;
jobj_removing = LUKS2_array_jobj(array, num);
if (!jobj_removing)
return NULL;
/* Create new array without jobj_removing. */
array_new = json_object_new_array();
for (i = 0; i < json_object_array_length(array); i++) {
jobj1 = json_object_array_get_idx(array, i);
if (jobj1 != jobj_removing)
json_object_array_add(array_new, json_object_get(jobj1));
}
return array_new;
}
/*
* JSON struct access helpers
*/
json_object *LUKS2_get_keyslot_jobj(struct luks2_hdr *hdr, int keyslot)
{
json_object *jobj1, *jobj2;
char keyslot_name[16];
if (!hdr)
return NULL;
if (snprintf(keyslot_name, sizeof(keyslot_name), "%u", keyslot) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "keyslots", &jobj1))
return NULL;
json_object_object_get_ex(jobj1, keyslot_name, &jobj2);
return jobj2;
}
json_object *LUKS2_get_token_jobj(struct luks2_hdr *hdr, int token)
{
json_object *jobj1, *jobj2;
char token_name[16];
if (!hdr)
return NULL;
if (snprintf(token_name, sizeof(token_name), "%u", token) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "tokens", &jobj1))
return NULL;
json_object_object_get_ex(jobj1, token_name, &jobj2);
return jobj2;
}
json_object *LUKS2_get_digest_jobj(struct luks2_hdr *hdr, int digest)
{
json_object *jobj1, *jobj2;
char digest_name[16];
if (!hdr)
return NULL;
if (snprintf(digest_name, sizeof(digest_name), "%u", digest) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "digests", &jobj1))
return NULL;
json_object_object_get_ex(jobj1, digest_name, &jobj2);
return jobj2;
}
json_object *LUKS2_get_segment_jobj(struct luks2_hdr *hdr, int segment)
{
json_object *jobj1, *jobj2;
char segment_name[16];
if (!hdr)
return NULL;
if (snprintf(segment_name, sizeof(segment_name), "%u", segment) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj1))
return NULL;
if (!json_object_object_get_ex(jobj1, segment_name, &jobj2))
return NULL;
return jobj2;
}
/*
* json_type_int needs to be validated first.
* See validate_json_uint32()
*/
uint32_t json_object_get_uint32(json_object *jobj)
{
return json_object_get_int64(jobj);
}
/* jobj has to be json_type_string and numbered */
/* FIXME: sscanf() instead? */
static json_bool json_str_to_uint64(json_object *jobj, uint64_t *value)
{
char *endptr;
unsigned long long tmp;
errno = 0;
tmp = strtoull(json_object_get_string(jobj), &endptr, 10);
if (*endptr || errno || tmp >= UINT64_MAX) {
log_dbg("Failed to parse uint64_t type from string %s.",
json_object_get_string(jobj));
*value = 0;
return FALSE;
}
*value = tmp;
return TRUE;
}
uint64_t json_object_get_uint64(json_object *jobj)
{
uint64_t r;
return json_str_to_uint64(jobj, &r) ? r : 0;
}
/*
* Validate helpers
*/
static json_bool numbered(const char *name, const char *key)
{
int i;
for (i = 0; key[i]; i++)
if (!isdigit(key[i])) {
log_dbg("%s \"%s\" is not in numbered form.", name, key);
return FALSE;
}
return TRUE;
}
static json_object *contains(json_object *jobj, const char *name,
const char *section, const char *key, json_type type)
{
json_object *sobj;
if (!json_object_object_get_ex(jobj, key, &sobj) ||
!json_object_is_type(sobj, type)) {
log_dbg("%s \"%s\" is missing \"%s\" (%s) specification.",
section, name, key, json_type_to_name(type));
return NULL;
}
return sobj;
}
/* use only on already validated 'segments' object */
static uint64_t get_first_data_offset(json_object *jobj_segs, const char *type)
{
json_object *jobj_offset, *jobj_type;
uint64_t tmp, min = UINT64_MAX;
json_object_object_foreach(jobj_segs, key, val) {
UNUSED(key);
if (type) {
json_object_object_get_ex(val, "type", &jobj_type);
if (strcmp(type, json_object_get_string(jobj_type)))
continue;
}
json_object_object_get_ex(val, "offset", &jobj_offset);
tmp = json_object_get_uint64(jobj_offset);
if (!tmp)
return tmp;
if (tmp < min)
min = tmp;
}
return min;
}
static json_bool validate_json_uint32(json_object *jobj)
{
int64_t tmp;
errno = 0;
tmp = json_object_get_int64(jobj);
return (errno || tmp < 0 || tmp > UINT32_MAX) ? FALSE : TRUE;
}
static json_bool validate_keyslots_array(json_object *jarr, json_object *jobj_keys)
{
json_object *jobj;
int i = 0, length = json_object_array_length(jarr);
while (i < length) {
jobj = json_object_array_get_idx(jarr, i);
if (!json_object_is_type(jobj, json_type_string)) {
log_dbg("Illegal value type in keyslots array at index %d.", i);
return FALSE;
}
if (!contains(jobj_keys, "", "Keyslots section", json_object_get_string(jobj), json_type_object))
return FALSE;
i++;
}
return TRUE;
}
static json_bool validate_segments_array(json_object *jarr, json_object *jobj_segments)
{
json_object *jobj;
int i = 0, length = json_object_array_length(jarr);
while (i < length) {
jobj = json_object_array_get_idx(jarr, i);
if (!json_object_is_type(jobj, json_type_string)) {
log_dbg("Illegal value type in segments array at index %d.", i);
return FALSE;
}
if (!contains(jobj_segments, "", "Segments section", json_object_get_string(jobj), json_type_object))
return FALSE;
i++;
}
return TRUE;
}
static json_bool segment_has_digest(const char *segment_name, json_object *jobj_digests)
{
json_object *jobj_segments;
json_object_object_foreach(jobj_digests, key, val) {
UNUSED(key);
json_object_object_get_ex(val, "segments", &jobj_segments);
if (LUKS2_array_jobj(jobj_segments, segment_name))
return TRUE;
}
return FALSE;
}
static json_bool validate_intervals(int length, const struct interval *ix, uint64_t *data_offset)
{
int j, i = 0;
while (i < length) {
if (ix[i].offset < 2 * LUKS2_HDR_16K_LEN) {
log_dbg("Illegal area offset: %" PRIu64 ".", ix[i].offset);
return FALSE;
}
if (!ix[i].length) {
log_dbg("Area length must be greater than zero.");
return FALSE;
}
/* first segment at offset 0 means we have detached header. Do not check then. */
if (*data_offset && (ix[i].offset + ix[i].length) > *data_offset) {
log_dbg("Area [%" PRIu64 ", %" PRIu64 "] intersects with segment starting at offset: %" PRIu64,
ix[i].offset, ix[i].offset + ix[i].length, *data_offset);
return FALSE;
}
for (j = 0; j < length; j++) {
if (i == j)
continue;
if ((ix[i].offset >= ix[j].offset) && (ix[i].offset < (ix[j].offset + ix[j].length))) {
log_dbg("Overlapping areas [%" PRIu64 ",%" PRIu64 "] and [%" PRIu64 ",%" PRIu64 "].",
ix[i].offset, ix[i].offset + ix[i].length,
ix[j].offset, ix[j].offset + ix[j].length);
return FALSE;
}
}
i++;
}
return TRUE;
}
static int hdr_validate_areas(json_object *hdr_jobj);
int LUKS2_keyslot_validate(json_object *hdr_jobj, json_object *hdr_keyslot, const char *key)
{
json_object *jobj_key_size;
if (!contains(hdr_keyslot, key, "Keyslot", "type", json_type_string))
return 1;
if (!(jobj_key_size = contains(hdr_keyslot, key, "Keyslot", "key_size", json_type_int)))
return 1;
/* enforce uint32_t type */
if (!validate_json_uint32(jobj_key_size)) {
log_dbg("Illegal field \"key_size\":%s.",
json_object_get_string(jobj_key_size));
return 1;
}
if (hdr_validate_areas(hdr_jobj))
return 1;
return 0;
}
int LUKS2_token_validate(json_object *hdr_jobj, json_object *jobj_token, const char *key)
{
json_object *jarr, *jobj_keyslots;
if (!json_object_object_get_ex(hdr_jobj, "keyslots", &jobj_keyslots))
return 1;
if (!contains(jobj_token, key, "Token", "type", json_type_string))
return 1;
jarr = contains(jobj_token, key, "Token", "keyslots", json_type_array);
if (!jarr)
return 1;
if (!validate_keyslots_array(jarr, jobj_keyslots))
return 1;
return 0;
}
static int hdr_validate_json_size(json_object *hdr_jobj)
{
json_object *jobj, *jobj1;
json_object_object_get_ex(hdr_jobj, "config", &jobj);
json_object_object_get_ex(jobj, "json_size", &jobj1);
return (strlen(json_object_to_json_string_ext(hdr_jobj, JSON_C_TO_STRING_PLAIN)) > json_object_get_uint64(jobj1));
}
int LUKS2_check_json_size(const struct luks2_hdr *hdr)
{
return hdr_validate_json_size(hdr->jobj);
}
static int hdr_validate_keyslots(json_object *hdr_jobj)
{
json_object *jobj;
if (!json_object_object_get_ex(hdr_jobj, "keyslots", &jobj)) {
log_dbg("Missing keyslots section.");
return 1;
}
json_object_object_foreach(jobj, key, val) {
if (!numbered("Keyslot", key))
return 1;
if (LUKS2_keyslot_validate(hdr_jobj, val, key))
return 1;
}
return 0;
}
static int hdr_validate_tokens(json_object *hdr_jobj)
{
json_object *jobj;
if (!json_object_object_get_ex(hdr_jobj, "tokens", &jobj)) {
log_dbg("Missing tokens section.");
return 1;
}
json_object_object_foreach(jobj, key, val) {
if (!numbered("Token", key))
return 1;
if (LUKS2_token_validate(hdr_jobj, val, key))
return 1;
}
return 0;
}
static int hdr_validate_segments(json_object *hdr_jobj)
{
json_object *jobj, *jobj_digests, *jobj_offset, *jobj_ivoffset,
*jobj_length, *jobj_sector_size, *jobj_type, *jobj_integrity;
uint32_t sector_size;
uint64_t ivoffset, offset, length;
if (!json_object_object_get_ex(hdr_jobj, "segments", &jobj)) {
log_dbg("Missing segments section.");
return 1;
}
if (json_object_object_length(jobj) < 1) {
log_dbg("Empty segments section.");
return 1;
}
/* digests should already be validated */
if (!json_object_object_get_ex(hdr_jobj, "digests", &jobj_digests))
return 1;
json_object_object_foreach(jobj, key, val) {
if (!numbered("Segment", key))
return 1;
if (!contains(val, key, "Segment", "type", json_type_string) ||
!(jobj_offset = contains(val, key, "Segment", "offset", json_type_string)) ||
!(jobj_ivoffset = contains(val, key, "Segment", "iv_tweak", json_type_string)) ||
!(jobj_length = contains(val, key, "Segment", "size", json_type_string)) ||
!contains(val, key, "Segment", "encryption", json_type_string) ||
!(jobj_sector_size = contains(val, key, "Segment", "sector_size", json_type_int)))
return 1;
/* integrity */
if (json_object_object_get_ex(val, "integrity", &jobj_integrity)) {
if (!contains(val, key, "Segment", "integrity", json_type_object) ||
!contains(jobj_integrity, key, "Segment integrity", "type", json_type_string) ||
!contains(jobj_integrity, key, "Segment integrity", "journal_encryption", json_type_string) ||
!contains(jobj_integrity, key, "Segment integrity", "journal_integrity", json_type_string))
return 1;
}
/* enforce uint32_t type */
if (!validate_json_uint32(jobj_sector_size)) {
log_dbg("Illegal field \"sector_size\":%s.",
json_object_get_string(jobj_sector_size));
return 1;
}
sector_size = json_object_get_uint32(jobj_sector_size);
if (!sector_size || sector_size % 512) {
log_dbg("Illegal sector size: %" PRIu32, sector_size);
return 1;
}
if (!numbered("offset", json_object_get_string(jobj_offset)) ||
!numbered("iv_tweak", json_object_get_string(jobj_ivoffset)))
return 1;
/* rule out values > UINT64_MAX */
if (!json_str_to_uint64(jobj_offset, &offset) ||
!json_str_to_uint64(jobj_ivoffset, &ivoffset))
return 1;
if (offset % sector_size) {
log_dbg("Offset field has to be aligned to sector size: %" PRIu32, sector_size);
return 1;
}
if (ivoffset % sector_size) {
log_dbg("IV offset field has to be aligned to sector size: %" PRIu32, sector_size);
return 1;
}
/* length "dynamic" means whole device starting at 'offset' */
if (strcmp(json_object_get_string(jobj_length), "dynamic")) {
if (!numbered("size", json_object_get_string(jobj_length)) ||
!json_str_to_uint64(jobj_length, &length))
return 1;
if (length % sector_size) {
log_dbg("Length field has to be aligned to sector size: %" PRIu32, sector_size);
return 1;
}
}
json_object_object_get_ex(val, "type", &jobj_type);
if (!strcmp(json_object_get_string(jobj_type), "crypt") &&
!segment_has_digest(key, jobj_digests))
return 1;
}
return 0;
}
static int hdr_validate_areas(json_object *hdr_jobj)
{
struct interval *intervals;
json_object *jobj_keyslots, *jobj_offset, *jobj_length, *jobj_segments, *jobj_area;
int length, ret, i = 0;
uint64_t first_offset;
/* keyslots should already be validated */
if (!json_object_object_get_ex(hdr_jobj, "keyslots", &jobj_keyslots))
return 1;
/* segments should already be validated */
if (!json_object_object_get_ex(hdr_jobj, "segments", &jobj_segments))
return 1;
length = json_object_object_length(jobj_keyslots);
/* Empty section */
if (length == 0)
return 0;
if (length < 0) {
log_dbg("Invalid keyslot areas specification.");
return 1;
}
intervals = malloc(length * sizeof(*intervals));
if (!intervals) {
log_dbg("Not enough memory.");
return -ENOMEM;
}
json_object_object_foreach(jobj_keyslots, key, val) {
if (!(jobj_area = contains(val, key, "Keyslot", "area", json_type_object)) ||
!(jobj_offset = contains(jobj_area, key, "Keyslot", "offset", json_type_string)) ||
!(jobj_length = contains(jobj_area, key, "Keyslot", "size", json_type_string)) ||
!numbered("offset", json_object_get_string(jobj_offset)) ||
!numbered("size", json_object_get_string(jobj_length))) {
free(intervals);
return 1;
}
/* rule out values > UINT64_MAX */
if (!json_str_to_uint64(jobj_offset, &intervals[i].offset) ||
!json_str_to_uint64(jobj_length, &intervals[i].length)) {
free(intervals);
return 1;
}
i++;
}
if (length != i) {
free(intervals);
return 1;
}
first_offset = get_first_data_offset(jobj_segments, NULL);
ret = validate_intervals(length, intervals, &first_offset) ? 0 : 1;
free(intervals);
return ret;
}
static int hdr_validate_digests(json_object *hdr_jobj)
{
json_object *jarr_keys, *jarr_segs, *jobj, *jobj_keyslots, *jobj_segments;
if (!json_object_object_get_ex(hdr_jobj, "digests", &jobj)) {
log_dbg("Missing digests section.");
return 1;
}
/* keyslots should already be validated */
if (!json_object_object_get_ex(hdr_jobj, "keyslots", &jobj_keyslots))
return 1;
/* segments are not validated atm, but we need to know digest doesn't reference missing segment */
if (!json_object_object_get_ex(hdr_jobj, "segments", &jobj_segments))
return 1;
json_object_object_foreach(jobj, key, val) {
if (!numbered("Digest", key))
return 1;
if (!contains(val, key, "Digest", "type", json_type_string) ||
!(jarr_keys = contains(val, key, "Digest", "keyslots", json_type_array)) ||
!(jarr_segs = contains(val, key, "Digest", "segments", json_type_array)))
return 1;
if (!validate_keyslots_array(jarr_keys, jobj_keyslots))
return 1;
if (!validate_segments_array(jarr_segs, jobj_segments))
return 1;
}
return 0;
}
/* requires keyslots and segments sections being already validated */
static int validate_keyslots_size(json_object *hdr_jobj, json_object *jobj_keyslots_size)
{
json_object *jobj_keyslots, *jobj, *jobj1;
uint64_t keyslots_size, segment_offset, keyslots_area_sum = 0;
if (!json_str_to_uint64(jobj_keyslots_size, &keyslots_size))
return 1;
if (keyslots_size % 4096) {
log_dbg("keyslots_size is not 4 KiB aligned");
return 1;
}
if (keyslots_size > LUKS2_MAX_KEYSLOTS_SIZE) {
log_dbg("keyslots_size is too large. The cap is %" PRIu64 " bytes", (uint64_t) LUKS2_MAX_KEYSLOTS_SIZE);
return 1;
}
json_object_object_get_ex(hdr_jobj, "segments", &jobj);
segment_offset = get_first_data_offset(jobj, "crypt");
if (segment_offset &&
(segment_offset < keyslots_size ||
(segment_offset - keyslots_size) < (2 * LUKS2_HDR_16K_LEN))) {
log_dbg("keyslots_size is too large %" PRIu64 " (bytes). Data offset: %" PRIu64 ", keyslots offset: %d", keyslots_size, segment_offset, 2 * LUKS2_HDR_16K_LEN);
return 1;
}
json_object_object_get_ex(hdr_jobj, "keyslots", &jobj_keyslots);
json_object_object_foreach(jobj_keyslots, key, val) {
UNUSED(key);
json_object_object_get_ex(val, "area", &jobj);
json_object_object_get_ex(jobj, "size", &jobj1);
keyslots_area_sum += json_object_get_uint64(jobj1);
}
if (keyslots_area_sum > keyslots_size) {
log_dbg("Sum of all keyslot area sizes (%" PRIu64 ") is greater than value in config section %" PRIu64, keyslots_area_sum, keyslots_size);
return 1;
}
return 0;
}
static int hdr_validate_config(json_object *hdr_jobj)
{
json_object *jobj_config, *jobj, *jobj1;
int i;
uint64_t json_size;
if (!json_object_object_get_ex(hdr_jobj, "config", &jobj_config)) {
log_dbg("Missing config section.");
return 1;
}
if (!(jobj = contains(jobj_config, "section", "Config", "json_size", json_type_string)) ||
!json_str_to_uint64(jobj, &json_size))
return 1;
/* currently it's hardcoded */
if (json_size != (LUKS2_HDR_16K_LEN - LUKS2_HDR_BIN_LEN)) {
log_dbg("Invalid json_size %" PRIu64, json_size);
return 1;
}
if (json_size % 4096) {
log_dbg("Json area is not properly aligned to 4 KiB.");
return 1;
}
if (!(jobj = contains(jobj_config, "section", "Config", "keyslots_size", json_type_string)))
return 1;
if (validate_keyslots_size(hdr_jobj, jobj))
return 1;
/* Flags array is optional */
if (json_object_object_get_ex(jobj_config, "flags", &jobj)) {
if (!contains(jobj_config, "section", "Config", "flags", json_type_array))
return 1;
/* All array members must be strings */
for (i = 0; i < json_object_array_length(jobj); i++)
if (!json_object_is_type(json_object_array_get_idx(jobj, i), json_type_string))
return 1;
}
/* Requirements object is optional */
if (json_object_object_get_ex(jobj_config, "requirements", &jobj)) {
if (!contains(jobj_config, "section", "Config", "requirements", json_type_object))
return 1;
/* Mandatory array is optional */
if (json_object_object_get_ex(jobj, "mandatory", &jobj1)) {
if (!contains(jobj, "section", "Requirements", "mandatory", json_type_array))
return 1;
/* All array members must be strings */
for (i = 0; i < json_object_array_length(jobj1); i++)
if (!json_object_is_type(json_object_array_get_idx(jobj1, i), json_type_string))
return 1;
}
}
return 0;
}
int LUKS2_hdr_validate(json_object *hdr_jobj)
{
struct {
int (*validate)(json_object *);
} checks[] = {
{ hdr_validate_keyslots },
{ hdr_validate_tokens },
{ hdr_validate_digests },
{ hdr_validate_segments },
{ hdr_validate_areas },
{ hdr_validate_config },
{ NULL }
};
int i;
if (!hdr_jobj)
return 1;
for (i = 0; checks[i].validate; i++)
if (checks[i].validate && checks[i].validate(hdr_jobj))
return 1;
if (hdr_validate_json_size(hdr_jobj)) {
log_dbg("Json header is too large.");
return 1;
}
return 0;
}
int LUKS2_hdr_read(struct crypt_device *cd, struct luks2_hdr *hdr)
{
int r;
r = device_read_lock(cd, crypt_metadata_device(cd));
if (r) {
log_err(cd, _("Failed to acquire read lock on device %s.\n"),
device_path(crypt_metadata_device(cd)));
return r;
}
r = LUKS2_disk_hdr_read(cd, hdr, crypt_metadata_device(cd), 1);
if (r == -EAGAIN) {
/* unlikely: auto-recovery is required and failed due to read lock being held */
device_read_unlock(crypt_metadata_device(cd));
r = device_write_lock(cd, crypt_metadata_device(cd));
if (r) {
log_err(cd, _("Failed to acquire write lock on device %s.\n"),
device_path(crypt_metadata_device(cd)));
return r;
}
r = LUKS2_disk_hdr_read(cd, hdr, crypt_metadata_device(cd), 1);
device_write_unlock(crypt_metadata_device(cd));
} else
device_read_unlock(crypt_metadata_device(cd));
return r;
}
/* NOTE: is called before LUKS2 validation routines */
static void LUKS2_hdr_free_unused_objects(struct crypt_device *cd, struct luks2_hdr *hdr)
{
/* erase unused digests (no assigned keyslot or segment) */
LUKS2_digests_erase_unused(cd, hdr);
}
int LUKS2_hdr_write(struct crypt_device *cd, struct luks2_hdr *hdr)
{
/* FIXME: we risk to hide future intenal implementation bugs with this */
LUKS2_hdr_free_unused_objects(cd, hdr);
if (LUKS2_hdr_validate(hdr->jobj))
return -EINVAL;
return LUKS2_disk_hdr_write(cd, hdr, crypt_metadata_device(cd));
}
int LUKS2_hdr_uuid(struct crypt_device *cd, struct luks2_hdr *hdr, const char *uuid)
{
uuid_t partitionUuid;
if (uuid && uuid_parse(uuid, partitionUuid) == -1) {
log_err(cd, _("Wrong LUKS UUID format provided.\n"));
return -EINVAL;
}
if (!uuid)
uuid_generate(partitionUuid);
uuid_unparse(partitionUuid, hdr->uuid);
/* FIXME: why is this not LUKS2_hdr_write? */
return LUKS2_disk_hdr_write(cd, hdr, crypt_metadata_device(cd));
}
int LUKS2_hdr_labels(struct crypt_device *cd, struct luks2_hdr *hdr,
const char *label, const char *subsystem, int commit)
{
//FIXME: check if the labels are the same and skip this.
memset(hdr->label, 0, LUKS2_LABEL_L);
if (label)
strncpy(hdr->label, label, LUKS2_LABEL_L-1);
memset(hdr->subsystem, 0, LUKS2_LABEL_L);
if (subsystem)
strncpy(hdr->subsystem, subsystem, LUKS2_LABEL_L-1);
return commit ? LUKS2_hdr_write(cd, hdr) : 0;
}
void LUKS2_hdr_free(struct luks2_hdr *hdr)
{
if (json_object_put(hdr->jobj))
hdr->jobj = NULL;
else if (hdr->jobj)
log_dbg("LUKS2 header still in use");
}
uint64_t LUKS2_keyslots_size(json_object *jobj)
{
json_object *jobj1, *jobj2;
uint64_t keyslots_size;
json_object_object_get_ex(jobj, "config", &jobj1);
json_object_object_get_ex(jobj1, "keyslots_size", &jobj2);
json_str_to_uint64(jobj2, &keyslots_size);
return keyslots_size;
}
uint64_t LUKS2_hdr_and_areas_size(json_object *jobj)
{
json_object *jobj1, *jobj2;
uint64_t json_size;
json_object_object_get_ex(jobj, "config", &jobj1);
json_object_object_get_ex(jobj1, "json_size", &jobj2);
json_str_to_uint64(jobj2, &json_size);
return 2 * (json_size + LUKS2_HDR_BIN_LEN) + LUKS2_keyslots_size(jobj);
}
int LUKS2_hdr_backup(struct crypt_device *cd, struct luks2_hdr *hdr,
const char *backup_file)
{
struct device *device = crypt_metadata_device(cd);
int r = 0, devfd = -1;
ssize_t hdr_size;
ssize_t buffer_size;
char *buffer = NULL;
hdr_size = LUKS2_hdr_and_areas_size(hdr->jobj);
buffer_size = size_round_up(hdr_size, crypt_getpagesize());
buffer = crypt_safe_alloc(buffer_size);
if (!buffer)
return -ENOMEM;
log_dbg("Storing backup of header (%zu bytes).", hdr_size);
log_dbg("Output backup file size: %zu bytes.", buffer_size);
r = device_read_lock(cd, device);
if (r) {
log_err(cd, _("Failed to acquire read lock on device %s.\n"),
device_path(crypt_metadata_device(cd)));
crypt_safe_free(buffer);
return r;
}
devfd = device_open_locked(device, O_RDONLY);
if (devfd < 0) {
device_read_unlock(device);
log_err(cd, _("Device %s is not a valid LUKS device.\n"), device_path(device));
crypt_safe_free(buffer);
return devfd == -1 ? -EINVAL : devfd;
}
if (read_blockwise(devfd, device_block_size(device),
device_alignment(device), buffer, hdr_size) < hdr_size) {
close(devfd);
device_read_unlock(device);
crypt_safe_free(buffer);
return -EIO;
}
close(devfd);
device_read_unlock(device);
devfd = open(backup_file, O_CREAT|O_EXCL|O_WRONLY, S_IRUSR);
if (devfd == -1) {
if (errno == EEXIST)
log_err(cd, _("Requested header backup file %s already exists.\n"), backup_file);
else
log_err(cd, _("Cannot create header backup file %s.\n"), backup_file);
crypt_safe_free(buffer);
return -EINVAL;
}
if (write_buffer(devfd, buffer, buffer_size) < buffer_size) {
log_err(cd, _("Cannot write header backup file %s.\n"), backup_file);
r = -EIO;
} else
r = 0;
close(devfd);
crypt_safe_free(buffer);
return r;
}
static int reqs_unknown(uint32_t reqs)
{
return reqs & CRYPT_REQUIREMENT_UNKNOWN;
}
int LUKS2_hdr_restore(struct crypt_device *cd, struct luks2_hdr *hdr,
const char *backup_file)
{
struct device *backup_device, *device = crypt_metadata_device(cd);
int r, devfd = -1, diff_uuid = 0;
ssize_t buffer_size = 0;
char *buffer = NULL, msg[1024];
struct luks2_hdr hdr_file;
struct luks2_hdr tmp_hdr = {};
uint32_t reqs = 0;
r = device_alloc(&backup_device, backup_file);
if (r < 0)
return r;
/* FIXME: why lock backup device ? */
r = device_read_lock(cd, backup_device);
if (r) {
log_err(cd, _("Failed to acquire read lock on device %s.\n"),
device_path(backup_device));
device_free(backup_device);
return r;
}
r = LUKS2_disk_hdr_read(cd, &hdr_file, backup_device, 0);
device_read_unlock(backup_device);
device_free(backup_device);
if (r < 0) {
log_err(cd, _("Backup file doesn't contain valid LUKS header.\n"));
return r;
}
/* do not allow header restore from backup with unmet requirements */
if (LUKS2_unmet_requirements(cd, &hdr_file, 0, 1)) {
log_err(cd, _("Unmet LUKS2 requirements detected in backup %s.\n"),
backup_file);
return -ETXTBSY;
}
buffer_size = LUKS2_hdr_and_areas_size(hdr_file.jobj);
buffer = crypt_safe_alloc(buffer_size);
if (!buffer) {
r = -ENOMEM;
goto out;
}
devfd = open(backup_file, O_RDONLY);
if (devfd == -1) {
log_err(cd, _("Cannot open header backup file %s.\n"), backup_file);
r = -EINVAL;
goto out;
}
if (read_buffer(devfd, buffer, buffer_size) < buffer_size) {
log_err(cd, _("Cannot read header backup file %s.\n"), backup_file);
r = -EIO;
goto out;
}
close(devfd);
devfd = -1;
r = LUKS2_hdr_read(cd, &tmp_hdr);
if (r == 0) {
r = LUKS2_config_get_requirements(cd, &tmp_hdr, &reqs);
if (r)
goto out;
log_dbg("Device %s already contains LUKS header, checking UUID and offset.", device_path(device));
if (LUKS2_get_data_offset(&tmp_hdr) != LUKS2_get_data_offset(&hdr_file)) {
log_err(cd, _("Data offset differ on device and backup, restore failed.\n"));
r = -EINVAL;
goto out;
}
/* FIXME: what could go wrong? Erase if we're fine with consequences */
if (buffer_size != (ssize_t) LUKS2_hdr_and_areas_size(tmp_hdr.jobj)) {
log_err(cd, _("Binary header with keyslot areas size differ on device and backup, restore failed.\n"));
r = -EINVAL;
goto out;
}
if (memcmp(tmp_hdr.uuid, hdr_file.uuid, LUKS2_UUID_L))
diff_uuid = 1;
}
r = snprintf(msg, sizeof(msg), _("Device %s %s%s%s"), device_path(device),
r ? _("does not contain LUKS2 header. Replacing header can destroy data on that device.") :
_("already contains LUKS2 header. Replacing header will destroy existing keyslots."),
diff_uuid ? _("\nWARNING: real device header has different UUID than backup!") : "",
reqs_unknown(reqs) ? _("\nWARNING: unknown LUKS2 requirements detected in real device header!"
"\nReplacing header with backup may corrupt the data on that device!") : "");
if (r < 0 || (size_t) r >= sizeof(msg)) {
r = -ENOMEM;
goto out;
}
if (!crypt_confirm(cd, msg)) {
r = -EINVAL;
goto out;
}
log_dbg("Storing backup of header (%zu bytes) to device %s.", buffer_size, device_path(device));
/* TODO: perform header restore on bdev in stand-alone routine? */
r = device_write_lock(cd, device);
if (r) {
log_err(cd, _("Failed to acquire write lock on device %s.\n"),
device_path(device));
goto out;
}
devfd = device_open_locked(device, O_RDWR);
if (devfd < 0) {
if (errno == EACCES)
log_err(cd, _("Cannot write to device %s, permission denied.\n"),
device_path(device));
else
log_err(cd, _("Cannot open device %s.\n"), device_path(device));
device_write_unlock(device);
r = -EINVAL;
goto out;
}
if (write_blockwise(devfd, device_block_size(device),
device_alignment(device), buffer, buffer_size) < buffer_size)
r = -EIO;
else
r = 0;
device_write_unlock(device);
/* end of TODO */
out:
LUKS2_hdr_free(&hdr_file);
LUKS2_hdr_free(&tmp_hdr);
crypt_memzero(&hdr_file, sizeof(hdr_file));
crypt_memzero(&tmp_hdr, sizeof(tmp_hdr));
crypt_safe_free(buffer);
if (devfd >= 0)
close(devfd);
if (!r) {
LUKS2_hdr_free(hdr);
r = LUKS2_hdr_read(cd, hdr);
}
return r;
}
/*
* Persistent config flags
*/
static const struct {
uint32_t flag;
const char *description;
} persistent_flags[] = {
{ CRYPT_ACTIVATE_ALLOW_DISCARDS, "allow-discards" },
{ CRYPT_ACTIVATE_SAME_CPU_CRYPT, "same-cpu-crypt" },
{ CRYPT_ACTIVATE_SUBMIT_FROM_CRYPT_CPUS, "submit-from-crypt-cpus" },
{ CRYPT_ACTIVATE_NO_JOURNAL, "no-journal" },
{ 0, NULL }
};
int LUKS2_config_get_flags(struct crypt_device *cd, struct luks2_hdr *hdr, uint32_t *flags)
{
json_object *jobj1, *jobj_config, *jobj_flags;
int i, j;
if (!hdr || !flags)
return -EINVAL;
if (!json_object_object_get_ex(hdr->jobj, "config", &jobj_config))
return 0;
if (!json_object_object_get_ex(jobj_config, "flags", &jobj_flags))
return 0;
for (i = 0; i < json_object_array_length(jobj_flags); i++) {
jobj1 = json_object_array_get_idx(jobj_flags, i);
for (j = 0; persistent_flags[j].description; j++) {
if (!strcmp(persistent_flags[j].description,
json_object_get_string(jobj1))) {
*flags |= persistent_flags[j].flag;
log_dbg("Using persistent flag %s.",
json_object_get_string(jobj1));
break;
}
log_verbose(cd, _("Ignored unknown flag %s."),
json_object_get_string(jobj1));
}
}
return 0;
}
int LUKS2_config_set_flags(struct crypt_device *cd, struct luks2_hdr *hdr, uint32_t flags)
{
json_object *jobj_config, *jobj_flags;
int i;
if (!json_object_object_get_ex(hdr->jobj, "config", &jobj_config))
return 0;
jobj_flags = json_object_new_array();
for (i = 0; persistent_flags[i].description; i++) {
if (flags & persistent_flags[i].flag)
json_object_array_add(jobj_flags,
json_object_new_string(persistent_flags[i].description));
}
/* Replace or add new flags array */
json_object_object_add(jobj_config, "flags", jobj_flags);
return LUKS2_hdr_write(cd, hdr);
}
/*
* json format example (mandatory array must not be ignored,
* all other future fields may be added later)
*
* "requirements": {
* mandatory : [],
* optional0 : [],
* optional1 : "lala"
* }
*/
static const struct {
uint32_t flag;
const char *description;
} requirements_flags[] = {
{ 0, NULL }
};
static uint32_t get_requirement_by_name(const char *requirement)
{
int i;
for (i = 0; requirements_flags[i].description; i++)
if (!strcmp(requirement, requirements_flags[i].description))
return requirements_flags[i].flag;
return CRYPT_REQUIREMENT_UNKNOWN;
}
/*
* returns count of requirements (past cryptsetup 2.0 release)
*/
int LUKS2_config_get_requirements(struct crypt_device *cd, struct luks2_hdr *hdr, uint32_t *reqs)
{
json_object *jobj_config, *jobj_requirements, *jobj_mandatory, *jobj;
int i, len;
uint32_t req;
assert(hdr);
if (!hdr || !reqs)
return -EINVAL;
*reqs = 0;
if (!json_object_object_get_ex(hdr->jobj, "config", &jobj_config))
return 0;
if (!json_object_object_get_ex(jobj_config, "requirements", &jobj_requirements))
return 0;
if (!json_object_object_get_ex(jobj_requirements, "mandatory", &jobj_mandatory))
return 0;
len = json_object_array_length(jobj_mandatory);
if (!len)
return 0;
log_dbg("LUKS2 requirements detected:");
for (i = 0; i < len; i++) {
jobj = json_object_array_get_idx(jobj_mandatory, i);
req = get_requirement_by_name(json_object_get_string(jobj));
log_dbg("%s - %sknown", json_object_get_string(jobj),
reqs_unknown(req) ? "un" : "");
*reqs |= req;
}
return 0;
}
int LUKS2_config_set_requirements(struct crypt_device *cd, struct luks2_hdr *hdr, uint32_t reqs)
{
int i, r = -EINVAL;
if (!hdr)
return -EINVAL;
json_object *jobj_config, *jobj_requirements, *jobj_mandatory, *jobj;
jobj_mandatory = json_object_new_array();
if (!jobj_mandatory)
return -ENOMEM;
for (i = 0; requirements_flags[i].description; i++) {
if (reqs & requirements_flags[i].flag) {
jobj = json_object_new_string(requirements_flags[i].description);
if (!jobj) {
r = -ENOMEM;
goto err;
}
json_object_array_add(jobj_mandatory, jobj);
/* erase processed flag from input set */
reqs &= ~(requirements_flags[i].flag);
}
}
/* any remaining bit in requirements is unknown therefore illegal */
if (reqs) {
log_dbg("Illegal requiremnt flag(s) requested");
goto err;
}
if (!json_object_object_get_ex(hdr->jobj, "config", &jobj_config))
goto err;
if (!json_object_object_get_ex(jobj_config, "requirements", &jobj_requirements)) {
jobj_requirements = json_object_new_object();
if (!jobj_requirements) {
r = -ENOMEM;
goto err;
}
json_object_object_add(jobj_config, "requirements", jobj_requirements);
}
if (json_object_array_length(jobj_mandatory)) {
/* replace mandatory field with new values */
json_object_object_add(jobj_requirements, "mandatory", jobj_mandatory);
} else {
/* new mandatory field was empty, delete old one */
json_object_object_del(jobj_requirements, "mandatory");
json_object_put(jobj_mandatory);
}
/* remove empty requirements object */
if (!json_object_object_length(jobj_requirements))
json_object_object_del(jobj_config, "requirements");
return LUKS2_hdr_write(cd, hdr);
err:
json_object_put(jobj_mandatory);
return r;
}
/*
* Header dump
*/
static void hdr_dump_config(struct crypt_device *cd, json_object *hdr_jobj)
{
json_object *jobj1, *jobj_config, *jobj_flags, *jobj_requirements, *jobj_mandatory;
int i = 0, flags = 0, reqs = 0;
log_std(cd, "Flags: \t");
if (json_object_object_get_ex(hdr_jobj, "config", &jobj_config)) {
if (json_object_object_get_ex(jobj_config, "flags", &jobj_flags))
flags = json_object_array_length(jobj_flags);
if (json_object_object_get_ex(jobj_config, "requirements", &jobj_requirements) &&
json_object_object_get_ex(jobj_requirements, "mandatory", &jobj_mandatory))
reqs = json_object_array_length(jobj_mandatory);
}
for (i = 0; i < flags; i++) {
jobj1 = json_object_array_get_idx(jobj_flags, i);
log_std(cd, "%s ", json_object_get_string(jobj1));
}
log_std(cd, "%s\n%s", flags ? "" : "(no flags)", reqs ? "" : "\n");
if (reqs) {
log_std(cd, "Requirements:\t");
for (i = 0; i < reqs; i++) {
jobj1 = json_object_array_get_idx(jobj_mandatory, i);
log_std(cd, "%s ", json_object_get_string(jobj1));
}
log_std(cd, "\n\n");
}
}
static const char *get_priority_desc(json_object *jobj)
{
crypt_keyslot_priority priority;
json_object *jobj_priority;
const char *text;
if (json_object_object_get_ex(jobj, "priority", &jobj_priority))
priority = (crypt_keyslot_priority)(int)json_object_get_int(jobj_priority);
else
priority = CRYPT_SLOT_PRIORITY_NORMAL;
switch (priority) {
case CRYPT_SLOT_PRIORITY_IGNORE: text = "ignored"; break;
case CRYPT_SLOT_PRIORITY_PREFER: text = "preferred"; break;
case CRYPT_SLOT_PRIORITY_NORMAL: text = "normal"; break;
default: text = "invalid";
}
return text;
}
static void hdr_dump_keyslots(struct crypt_device *cd, json_object *hdr_jobj)
{
char slot[16];
json_object *keyslots_jobj, *digests_jobj, *jobj2, *jobj3, *val;
const char *tmps;
int i, j, r;
log_std(cd, "Keyslots:\n");
json_object_object_get_ex(hdr_jobj, "keyslots", &keyslots_jobj);
for (j = 0; j < LUKS2_KEYSLOTS_MAX; j++) {
(void) snprintf(slot, sizeof(slot), "%i", j);
json_object_object_get_ex(keyslots_jobj, slot, &val);
if (!val)
continue;
json_object_object_get_ex(val, "type", &jobj2);
tmps = json_object_get_string(jobj2);
r = LUKS2_keyslot_for_segment(crypt_get_hdr(cd, CRYPT_LUKS2), j, CRYPT_DEFAULT_SEGMENT);
log_std(cd, " %s: %s%s\n", slot, tmps, r == -ENOENT ? " (unbound)" : "");
if (json_object_object_get_ex(val, "key_size", &jobj2))
log_std(cd, "\tKey: %u bits\n", json_object_get_uint32(jobj2) * 8);
log_std(cd, "\tPriority: %s\n", get_priority_desc(val));
LUKS2_keyslot_dump(cd, j);
json_object_object_get_ex(hdr_jobj, "digests", &digests_jobj);
json_object_object_foreach(digests_jobj, key2, val2) {
json_object_object_get_ex(val2, "keyslots", &jobj2);
for (i = 0; i < json_object_array_length(jobj2); i++) {
jobj3 = json_object_array_get_idx(jobj2, i);
if (!strcmp(slot, json_object_get_string(jobj3))) {
log_std(cd, "\tDigest ID: %s\n", key2);
}
}
}
}
}
static void hdr_dump_tokens(struct crypt_device *cd, json_object *hdr_jobj)
{
char token[16];
json_object *tokens_jobj, *jobj2, *jobj3, *val;
const char *tmps;
int i, j;
log_std(cd, "Tokens:\n");
json_object_object_get_ex(hdr_jobj, "tokens", &tokens_jobj);
for (j = 0; j < LUKS2_TOKENS_MAX; j++) {
(void) snprintf(token, sizeof(token), "%i", j);
json_object_object_get_ex(tokens_jobj, token, &val);
if (!val)
continue;
json_object_object_get_ex(val, "type", &jobj2);
tmps = json_object_get_string(jobj2);
log_std(cd, " %s: %s\n", token, tmps);
LUKS2_token_dump(cd, j);
json_object_object_get_ex(val, "keyslots", &jobj2);
for (i = 0; i < json_object_array_length(jobj2); i++) {
jobj3 = json_object_array_get_idx(jobj2, i);
log_std(cd, "\tKeyslot: %s\n", json_object_get_string(jobj3));
}
}
}
/* FIXME: sort segments when more segments available later */
static void hdr_dump_segments(struct crypt_device *cd, json_object *hdr_jobj)
{
json_object *jobj1, *jobj2, *jobj3;
uint64_t value;
log_std(cd, "Data segments:\n");
json_object_object_get_ex(hdr_jobj, "segments", &jobj1);
json_object_object_foreach(jobj1, key, val) {
json_object_object_get_ex(val, "type", &jobj2);
log_std(cd, " %s: %s\n", key, json_object_get_string(jobj2));
json_object_object_get_ex(val, "offset", &jobj3);
json_str_to_uint64(jobj3, &value);
log_std(cd, "\toffset: %" PRIu64 " [bytes]\n", value);
json_object_object_get_ex(val, "size", &jobj3);
if (!(strcmp(json_object_get_string(jobj3), "dynamic")))
log_std(cd, "\tlength: (whole device)\n");
else {
json_str_to_uint64(jobj3, &value);
log_std(cd, "\tlength: %" PRIu64 " [bytes]\n", value);
}
json_object_object_get_ex(val, "encryption", &jobj3);
log_std(cd, "\tcipher: %s\n", json_object_get_string(jobj3));
json_object_object_get_ex(val, "sector_size", &jobj3);
log_std(cd, "\tsector: %" PRIu32 " [bytes]\n", json_object_get_uint32(jobj3));
if (json_object_object_get_ex(val, "integrity", &jobj2) &&
json_object_object_get_ex(jobj2, "type", &jobj3))
log_std(cd, "\tintegrity: %s\n", json_object_get_string(jobj3));
log_std(cd, "\n");
}
}
static void hdr_dump_digests(struct crypt_device *cd, json_object *hdr_jobj)
{
char key[16];
json_object *jobj1, *jobj2, *val;
const char *tmps;
int i;
log_std(cd, "Digests:\n");
json_object_object_get_ex(hdr_jobj, "digests", &jobj1);
for (i = 0; i < LUKS2_DIGEST_MAX; i++) {
(void) snprintf(key, sizeof(key), "%i", i);
json_object_object_get_ex(jobj1, key, &val);
if (!val)
continue;
json_object_object_get_ex(val, "type", &jobj2);
tmps = json_object_get_string(jobj2);
log_std(cd, " %s: %s\n", key, tmps);
LUKS2_digest_dump(cd, i);
}
}
int LUKS2_hdr_dump(struct crypt_device *cd, struct luks2_hdr *hdr)
{
if (!hdr->jobj)
return -EINVAL;
JSON_DBG(hdr->jobj, NULL);
log_std(cd, "LUKS header information\n");
log_std(cd, "Version: \t%u\n", hdr->version);
log_std(cd, "Epoch: \t%" PRIu64 "\n", hdr->seqid);
log_std(cd, "Metadata area: \t%zu bytes\n", hdr->hdr_size - LUKS2_HDR_BIN_LEN);
log_std(cd, "UUID: \t%s\n", *hdr->uuid ? hdr->uuid : "(no UUID)");
log_std(cd, "Label: \t%s\n", *hdr->label ? hdr->label : "(no label)");
log_std(cd, "Subsystem: \t%s\n", *hdr->subsystem ? hdr->subsystem : "(no subsystem)");
hdr_dump_config(cd, hdr->jobj);
hdr_dump_segments(cd, hdr->jobj);
hdr_dump_keyslots(cd, hdr->jobj);
hdr_dump_tokens(cd, hdr->jobj);
hdr_dump_digests(cd, hdr->jobj);
return 0;
}
uint64_t LUKS2_get_data_offset(struct luks2_hdr *hdr)
{
json_object *jobj1;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj1))
return 0;
return get_first_data_offset(jobj1, "crypt") / SECTOR_SIZE;
}
const char *LUKS2_get_cipher(struct luks2_hdr *hdr, int segment)
{
json_object *jobj1, *jobj2, *jobj3;
char buf[16];
if (segment < 0 || snprintf(buf, sizeof(buf), "%u", segment) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj1))
return 0;
if (!json_object_object_get_ex(jobj1, buf, &jobj2))
return 0;
if (!json_object_object_get_ex(jobj2, "encryption", &jobj3))
return 0;
return json_object_get_string(jobj3);
}
const char *LUKS2_get_integrity(struct luks2_hdr *hdr, int segment)
{
json_object *jobj1, *jobj2, *jobj3, *jobj4;
char buf[16];
if (segment < 0 || snprintf(buf, sizeof(buf), "%u", segment) < 1)
return NULL;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj1))
return 0;
if (!json_object_object_get_ex(jobj1, buf, &jobj2))
return 0;
if (!json_object_object_get_ex(jobj2, "integrity", &jobj3))
return 0;
if (!json_object_object_get_ex(jobj3, "type", &jobj4))
return 0;
return json_object_get_string(jobj4);
}
/* FIXME: this only ensures that once we have journal encryption, it is not ignored. */
static int LUKS2_integrity_compatible(struct luks2_hdr *hdr)
{
json_object *jobj1, *jobj2, *jobj3, *jobj4;
const char *str;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj1))
return 0;
if (!json_object_object_get_ex(jobj1, CRYPT_DEFAULT_SEGMENT_STR, &jobj2))
return 0;
if (!json_object_object_get_ex(jobj2, "integrity", &jobj3))
return 0;
if (!json_object_object_get_ex(jobj3, "journal_encryption", &jobj4) ||
!(str = json_object_get_string(jobj4)) ||
strcmp(str, "none"))
return 0;
if (!json_object_object_get_ex(jobj3, "journal_integrity", &jobj4) ||
!(str = json_object_get_string(jobj4)) ||
strcmp(str, "none"))
return 0;
return 1;
}
static int LUKS2_keyslot_get_volume_key_size(struct luks2_hdr *hdr, const char *keyslot)
{
json_object *jobj1, *jobj2, *jobj3;
if (!json_object_object_get_ex(hdr->jobj, "keyslots", &jobj1))
return 0;
if (!json_object_object_get_ex(jobj1, keyslot, &jobj2))
return 0;
if (!json_object_object_get_ex(jobj2, "key_size", &jobj3))
return 0;
return json_object_get_int(jobj3);
}
int LUKS2_get_keyslot_key_size(struct luks2_hdr *hdr, int keyslot)
{
char keyslot_name[16];
if (snprintf(keyslot_name, sizeof(keyslot_name), "%u", keyslot) < 1)
return -1;
return LUKS2_keyslot_get_volume_key_size(hdr, keyslot_name);
}
int LUKS2_get_volume_key_size(struct luks2_hdr *hdr, int segment)
{
json_object *jobj_digests, *jobj_digest_segments, *jobj_digest_keyslots, *jobj1;
char buf[16];
if (snprintf(buf, sizeof(buf), "%u", segment) < 1)
return -1;
json_object_object_get_ex(hdr->jobj, "digests", &jobj_digests);
json_object_object_foreach(jobj_digests, key, val) {
UNUSED(key);
json_object_object_get_ex(val, "segments", &jobj_digest_segments);
json_object_object_get_ex(val, "keyslots", &jobj_digest_keyslots);
if (!LUKS2_array_jobj(jobj_digest_segments, buf))
continue;
if (!json_object_array_length(jobj_digest_keyslots))
continue;
jobj1 = json_object_array_get_idx(jobj_digest_keyslots, 0);
return LUKS2_keyslot_get_volume_key_size(hdr, json_object_get_string(jobj1));
}
return -1;
}
int LUKS2_get_sector_size(struct luks2_hdr *hdr)
{
json_object *jobj1, *jobj_segment;
jobj_segment = LUKS2_get_segment_jobj(hdr, CRYPT_DEFAULT_SEGMENT);
if (!jobj_segment)
return SECTOR_SIZE;
json_object_object_get_ex(jobj_segment, "sector_size", &jobj1);
if (!jobj1)
return SECTOR_SIZE;
return json_object_get_int(jobj1);
}
int LUKS2_activate(struct crypt_device *cd,
const char *name,
struct volume_key *vk,
uint32_t flags)
{
int r;
enum devcheck device_check;
struct luks2_hdr *hdr = crypt_get_hdr(cd, CRYPT_LUKS2);
struct crypt_dm_active_device dmd = {
.target = DM_CRYPT,
.uuid = crypt_get_uuid(cd),
.flags = flags,
.size = 0,
.data_device = crypt_data_device(cd),
.u.crypt = {
.vk = vk,
.offset = crypt_get_data_offset(cd),
.cipher = LUKS2_get_cipher(hdr, 0),
.integrity = crypt_get_integrity(cd),
.iv_offset = 0,
.tag_size = crypt_get_integrity_tag_size(cd),
.sector_size = crypt_get_sector_size(cd)
}
};
char dm_int_name[PATH_MAX], dm_int_dev_name[PATH_MAX];
struct device *device = NULL;
/* do not allow activation when particular requirements detected */
if ((r = LUKS2_unmet_requirements(cd, hdr, 0, 0)))
return r;
/* Add persistent activation flags */
if (!(flags & CRYPT_ACTIVATE_IGNORE_PERSISTENT))
LUKS2_config_get_flags(cd, hdr, &dmd.flags);
if (dmd.flags & CRYPT_ACTIVATE_SHARED)
device_check = DEV_SHARED;
else
device_check = DEV_EXCL;
if (dmd.u.crypt.tag_size) {
if (!LUKS2_integrity_compatible(hdr)) {
log_err(cd, "Unsupported device integrity configuration.\n");
return -EINVAL;
}
snprintf(dm_int_name, sizeof(dm_int_name), "%s_dif", name);
r = INTEGRITY_activate(cd, dm_int_name, NULL, NULL, NULL, NULL, flags);
if (r)
return r;
snprintf(dm_int_dev_name, sizeof(dm_int_dev_name), "%s/%s", dm_get_dir(), dm_int_name);
r = device_alloc(&device, dm_int_dev_name);
if (r) {
dm_remove_device(cd, dm_int_name, 0);
return r;
}
/* Space for IV metadata only */
if (!dmd.u.crypt.integrity)
dmd.u.crypt.integrity = "none";
dmd.data_device = device;
dmd.u.crypt.offset = 0;
r = INTEGRITY_data_sectors(cd, crypt_data_device(cd),
crypt_get_data_offset(cd) * SECTOR_SIZE,
&dmd.size);
if (r < 0) {
log_err(cd, "Cannot detect integrity device size.\n");
dm_remove_device(cd, dm_int_name, 0);
return r;
}
}
r = device_block_adjust(cd, dmd.data_device, device_check,
dmd.u.crypt.offset, &dmd.size, &dmd.flags);
if (!r)
r = dm_create_device(cd, name, CRYPT_LUKS2, &dmd, 0);
if (r < 0 && dmd.u.crypt.integrity)
dm_remove_device(cd, dm_int_name, 0);
device_free(device);
return r;
}
int LUKS2_unmet_requirements(struct crypt_device *cd, struct luks2_hdr *hdr, uint32_t reqs_mask, int quiet)
{
uint32_t reqs;
int r = LUKS2_config_get_requirements(cd, hdr, &reqs);
if (r) {
if (!quiet)
log_err(cd, _("Failed to read LUKS2 requierements.\n"));
return r;
}
/* do not mask unknown requirements check */
if (reqs_unknown(reqs)) {
if (!quiet)
log_err(cd, _("Unmet LUKS2 requirements detected.\n"));
return -ETXTBSY;
}
/* mask out permitted requirements */
reqs &= ~reqs_mask;
/* any remaining unmasked requirement fails the check */
return reqs ? -EINVAL : 0;
}