/*
* LUKS - Linux Unified Key Setup
*
- * Copyright (C) 2004-2006, Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2004-2006 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2021 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2012-2021 Milan Broz
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
+ * 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
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#include <string.h>
#include <stdio.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <sys/utsname.h>
-#include <fcntl.h>
-#include <unistd.h>
+#include <string.h>
#include <errno.h>
-#include <signal.h>
-
+#include <sys/stat.h>
#include "luks.h"
+#include "af.h"
#include "internal.h"
-#define div_round_up(a,b) ({ \
- typeof(a) __a = (a); \
- typeof(b) __b = (b); \
- (__a - 1) / __b + 1; \
-})
-
-static inline int round_up_modulo(int x, int m) {
- return div_round_up(x, m) * m;
-}
-
-static const char *cleaner_name=NULL;
-static uint64_t cleaner_size = 0;
-static int devfd=-1;
-
-static int setup_mapping(const char *cipher, const char *name,
- const char *device,
- struct volume_key *vk,
- unsigned int sector, size_t srcLength,
- int mode, struct crypt_device *ctx)
+static void _error_hint(struct crypt_device *ctx, const char *device,
+ const char *cipher, const char *mode, size_t keyLength)
{
- int device_sector_size = sector_size_for_device(device);
- struct crypt_dm_active_device dmd = {
- .device = device,
- .cipher = cipher,
- .uuid = NULL,
- .vk = vk,
- .offset = sector,
- .iv_offset = 0,
- .size = 0,
- .flags = (mode == O_RDONLY) ? CRYPT_ACTIVATE_READONLY : 0
- };
-
- /*
- * we need to round this to nearest multiple of the underlying
- * device's sector size, otherwise the mapping will be refused.
- */
- if(device_sector_size < 0) {
- log_err(ctx, _("Unable to obtain sector size for %s"), device);
- return -EINVAL;
- }
+ char *c, cipher_spec[MAX_CIPHER_LEN * 3];
- dmd.size = round_up_modulo(srcLength,device_sector_size)/SECTOR_SIZE;
- cleaner_size = dmd.size;
+ if (snprintf(cipher_spec, sizeof(cipher_spec), "%s-%s", cipher, mode) < 0)
+ return;
- return dm_create_device(name, "TEMP", &dmd, 0);
-}
-
-static void sigint_handler(int sig __attribute__((unused)))
-{
- if(devfd >= 0)
- close(devfd);
- devfd = -1;
- if(cleaner_name)
- dm_remove_device(cleaner_name, 1, cleaner_size);
+ log_err(ctx, _("Failed to setup dm-crypt key mapping for device %s.\n"
+ "Check that kernel supports %s cipher (check syslog for more info)."),
+ device, cipher_spec);
- signal(SIGINT, SIG_DFL);
- kill(getpid(), SIGINT);
+ if (!strncmp(mode, "xts", 3) && (keyLength != 256 && keyLength != 512))
+ log_err(ctx, _("Key size in XTS mode must be 256 or 512 bits."));
+ else if (!(c = strchr(mode, '-')) || strlen(c) < 4)
+ log_err(ctx, _("Cipher specification should be in [cipher]-[mode]-[iv] format."));
}
-static const char *_error_hint(char *cipherMode, size_t keyLength)
-{
- const char *hint= "";
-#ifdef __linux__
- char c, tmp[4] = {0};
- struct utsname uts;
- int i = 0, kernel_minor;
-
- /* Nothing to suggest here */
- if (uname(&uts) || strncmp(uts.release, "2.6.", 4))
- return hint;
-
- /* Get kernel minor without suffixes */
- while (i < 3 && (c = uts.release[i + 4]))
- tmp[i++] = isdigit(c) ? c : '\0';
- kernel_minor = atoi(tmp);
-
- if (!strncmp(cipherMode, "xts", 3) && (keyLength != 256 && keyLength != 512))
- hint = _("Key size in XTS mode must be 256 or 512 bits.\n");
- else if (!strncmp(cipherMode, "xts", 3) && kernel_minor < 24)
- hint = _("Block mode XTS is available since kernel 2.6.24.\n");
- if (!strncmp(cipherMode, "lrw", 3) && (keyLength != 256 && keyLength != 512))
- hint = _("Key size in LRW mode must be 256 or 512 bits.\n");
- else if (!strncmp(cipherMode, "lrw", 3) && kernel_minor < 20)
- hint = _("Block mode LRW is available since kernel 2.6.20.\n");
-#endif
- return hint;
-}
-
-/* This function is not reentrant safe, as it installs a signal
- handler and global vars for cleaning */
static int LUKS_endec_template(char *src, size_t srcLength,
- struct luks_phdr *hdr,
+ const char *cipher, const char *cipher_mode,
struct volume_key *vk,
- const char *device,
unsigned int sector,
- ssize_t (*func)(int, void *, size_t),
+ ssize_t (*func)(int, size_t, size_t, void *, size_t),
int mode,
struct crypt_device *ctx)
{
- char *name = NULL;
- char *fullpath = NULL;
- char *dmCipherSpec = NULL;
- const char *dmDir = dm_get_dir();
- int r = -1;
-
- if(dmDir == NULL) {
- log_err(ctx, _("Failed to obtain device mapper directory."));
- return -1;
+ char name[PATH_MAX], path[PATH_MAX];
+ char cipher_spec[MAX_CIPHER_LEN * 3];
+ struct crypt_dm_active_device dmd = {
+ .flags = CRYPT_ACTIVATE_PRIVATE,
+ };
+ int r, devfd = -1, remove_dev = 0;
+ size_t bsize, keyslot_alignment, alignment;
+
+ log_dbg(ctx, "Using dmcrypt to access keyslot area.");
+
+ bsize = device_block_size(ctx, crypt_metadata_device(ctx));
+ alignment = device_alignment(crypt_metadata_device(ctx));
+ if (!bsize || !alignment)
+ return -EINVAL;
+
+ if (bsize > LUKS_ALIGN_KEYSLOTS)
+ keyslot_alignment = LUKS_ALIGN_KEYSLOTS;
+ else
+ keyslot_alignment = bsize;
+ dmd.size = size_round_up(srcLength, keyslot_alignment) / SECTOR_SIZE;
+
+ if (mode == O_RDONLY)
+ dmd.flags |= CRYPT_ACTIVATE_READONLY;
+
+ if (snprintf(name, sizeof(name), "temporary-cryptsetup-%d", getpid()) < 0)
+ return -ENOMEM;
+ if (snprintf(path, sizeof(path), "%s/%s", dm_get_dir(), name) < 0)
+ return -ENOMEM;
+ if (snprintf(cipher_spec, sizeof(cipher_spec), "%s-%s", cipher, cipher_mode) < 0)
+ return -ENOMEM;
+
+ r = device_block_adjust(ctx, crypt_metadata_device(ctx), DEV_OK,
+ sector, &dmd.size, &dmd.flags);
+ if (r < 0) {
+ log_err(ctx, _("Device %s does not exist or access denied."),
+ device_path(crypt_metadata_device(ctx)));
+ return -EIO;
}
- if(asprintf(&name,"temporary-cryptsetup-%d",getpid()) == -1 ||
- asprintf(&fullpath,"%s/%s",dmDir,name) == -1 ||
- asprintf(&dmCipherSpec,"%s-%s",hdr->cipherName, hdr->cipherMode) == -1) {
- r = -ENOMEM;
- goto out1;
- }
-
- signal(SIGINT, sigint_handler);
- cleaner_name = name;
-
- r = setup_mapping(dmCipherSpec, name, device,
- vk, sector, srcLength, mode, ctx);
- if(r < 0) {
- log_err(ctx, _("Failed to setup dm-crypt key mapping for device %s.\n"
- "Check that kernel supports %s cipher (check syslog for more info).\n%s"),
- device, dmCipherSpec,
- _error_hint(hdr->cipherMode, vk->keylength * 8));
- r = -EIO;
- goto out1;
+
+ if (mode != O_RDONLY && dmd.flags & CRYPT_ACTIVATE_READONLY) {
+ log_err(ctx, _("Cannot write to device %s, permission denied."),
+ device_path(crypt_metadata_device(ctx)));
+ return -EACCES;
}
- devfd = open(fullpath, mode | O_DIRECT | O_SYNC); /* devfd is a global var */
- if(devfd == -1) {
- log_err(ctx, _("Failed to open temporary keystore device.\n"));
+ r = dm_crypt_target_set(&dmd.segment, 0, dmd.size,
+ crypt_metadata_device(ctx), vk, cipher_spec, 0, sector,
+ NULL, 0, SECTOR_SIZE);
+ if (r)
+ goto out;
+
+ r = dm_create_device(ctx, name, "TEMP", &dmd);
+ if (r < 0) {
+ if (r != -EACCES && r != -ENOTSUP)
+ _error_hint(ctx, device_path(crypt_metadata_device(ctx)),
+ cipher, cipher_mode, vk->keylength * 8);
r = -EIO;
- goto out2;
+ goto out;
}
+ remove_dev = 1;
- r = func(devfd,src,srcLength);
- if(r < 0) {
- log_err(ctx, _("Failed to access temporary keystore device.\n"));
+ devfd = open(path, mode | O_DIRECT | O_SYNC);
+ if (devfd == -1) {
+ log_err(ctx, _("Failed to open temporary keystore device."));
r = -EIO;
- goto out3;
+ goto out;
}
- r = 0;
- out3:
- close(devfd);
- devfd = -1;
- out2:
- dm_remove_device(cleaner_name, 1, cleaner_size);
- out1:
- signal(SIGINT, SIG_DFL);
- cleaner_name = NULL;
- cleaner_size = 0;
- free(dmCipherSpec);
- free(fullpath);
- free(name);
+ r = func(devfd, bsize, alignment, src, srcLength);
+ if (r < 0) {
+ log_err(ctx, _("Failed to access temporary keystore device."));
+ r = -EIO;
+ } else
+ r = 0;
+ out:
+ dm_targets_free(ctx, &dmd);
+ if (devfd != -1)
+ close(devfd);
+ if (remove_dev)
+ dm_remove_device(ctx, name, CRYPT_DEACTIVATE_FORCE);
return r;
}
int LUKS_encrypt_to_storage(char *src, size_t srcLength,
- struct luks_phdr *hdr,
+ const char *cipher,
+ const char *cipher_mode,
struct volume_key *vk,
- const char *device,
unsigned int sector,
struct crypt_device *ctx)
{
- return LUKS_endec_template(src,srcLength,hdr,vk, device,
- sector, write_blockwise, O_RDWR, ctx);
+ struct device *device = crypt_metadata_device(ctx);
+ struct crypt_storage *s;
+ int devfd, r = 0;
+
+ /* Only whole sector writes supported */
+ if (MISALIGNED_512(srcLength))
+ return -EINVAL;
+
+ /* Encrypt buffer */
+ r = crypt_storage_init(&s, SECTOR_SIZE, cipher, cipher_mode, vk->key, vk->keylength, false);
+
+ if (r)
+ log_dbg(ctx, "Userspace crypto wrapper cannot use %s-%s (%d).",
+ cipher, cipher_mode, r);
+
+ /* Fallback to old temporary dmcrypt device */
+ if (r == -ENOTSUP || r == -ENOENT)
+ return LUKS_endec_template(src, srcLength, cipher, cipher_mode,
+ vk, sector, write_blockwise, O_RDWR, ctx);
+
+ if (r) {
+ _error_hint(ctx, device_path(device), cipher, cipher_mode,
+ vk->keylength * 8);
+ return r;
+ }
+
+ log_dbg(ctx, "Using userspace crypto wrapper to access keyslot area.");
+
+ r = crypt_storage_encrypt(s, 0, srcLength, src);
+ crypt_storage_destroy(s);
+
+ if (r)
+ return r;
+
+ r = -EIO;
+
+ /* Write buffer to device */
+ if (device_is_locked(device))
+ devfd = device_open_locked(ctx, device, O_RDWR);
+ else
+ devfd = device_open(ctx, device, O_RDWR);
+ if (devfd < 0)
+ goto out;
+
+ if (write_lseek_blockwise(devfd, device_block_size(ctx, device),
+ device_alignment(device), src, srcLength,
+ sector * SECTOR_SIZE) < 0)
+ goto out;
+
+ r = 0;
+out:
+ device_sync(ctx, device);
+ if (r)
+ log_err(ctx, _("IO error while encrypting keyslot."));
+
+ return r;
}
int LUKS_decrypt_from_storage(char *dst, size_t dstLength,
- struct luks_phdr *hdr,
+ const char *cipher,
+ const char *cipher_mode,
struct volume_key *vk,
- const char *device,
unsigned int sector,
struct crypt_device *ctx)
{
- return LUKS_endec_template(dst,dstLength,hdr,vk, device,
- sector, read_blockwise, O_RDONLY, ctx);
+ struct device *device = crypt_metadata_device(ctx);
+ struct crypt_storage *s;
+ struct stat st;
+ int devfd, r = 0;
+
+ /* Only whole sector reads supported */
+ if (MISALIGNED_512(dstLength))
+ return -EINVAL;
+
+ r = crypt_storage_init(&s, SECTOR_SIZE, cipher, cipher_mode, vk->key, vk->keylength, false);
+
+ if (r)
+ log_dbg(ctx, "Userspace crypto wrapper cannot use %s-%s (%d).",
+ cipher, cipher_mode, r);
+
+ /* Fallback to old temporary dmcrypt device */
+ if (r == -ENOTSUP || r == -ENOENT)
+ return LUKS_endec_template(dst, dstLength, cipher, cipher_mode,
+ vk, sector, read_blockwise, O_RDONLY, ctx);
+
+ if (r) {
+ _error_hint(ctx, device_path(device), cipher, cipher_mode,
+ vk->keylength * 8);
+ return r;
+ }
+
+ log_dbg(ctx, "Using userspace crypto wrapper to access keyslot area.");
+
+ /* Read buffer from device */
+ if (device_is_locked(device))
+ devfd = device_open_locked(ctx, device, O_RDONLY);
+ else
+ devfd = device_open(ctx, device, O_RDONLY);
+ if (devfd < 0) {
+ log_err(ctx, _("Cannot open device %s."), device_path(device));
+ crypt_storage_destroy(s);
+ return -EIO;
+ }
+
+ if (read_lseek_blockwise(devfd, device_block_size(ctx, device),
+ device_alignment(device), dst, dstLength,
+ sector * SECTOR_SIZE) < 0) {
+ if (!fstat(devfd, &st) && (st.st_size < (off_t)dstLength))
+ log_err(ctx, _("Device %s is too small."), device_path(device));
+ else
+ log_err(ctx, _("IO error while decrypting keyslot."));
+
+ crypt_storage_destroy(s);
+ return -EIO;
+ }
+
+ /* Decrypt buffer */
+ r = crypt_storage_decrypt(s, 0, dstLength, dst);
+ crypt_storage_destroy(s);
+
+ return r;
}