Merge branch 'upstream' into tizen
[platform/upstream/cryptsetup.git] / lib / luks1 / keyencryption.c
index 05bc382..c1c8201 100644 (file)
@@ -1,12 +1,14 @@
 /*
  * LUKS - Linux Unified Key Setup
  *
- * Copyright (C) 2004-2006, Clemens Fruhwirth <clemens@endorphin.org>
- * Copyright (C) 2009-2012, Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004-2006 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2023 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2012-2023 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
  * 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 void _error_hint(struct crypt_device *ctx, const char *device,
+                       const char *cipher, const char *mode, size_t keyLength)
+{
+       char *c, cipher_spec[MAX_CIPHER_LEN * 3];
 
-static inline int round_up_modulo(int x, int m) {
-       return div_round_up(x, m) * m;
-}
+       if (snprintf(cipher_spec, sizeof(cipher_spec), "%s-%s", cipher, mode) < 0)
+               return;
 
-static const char *cleaner_name=NULL;
-static uint64_t cleaner_size = 0;
-static int devfd=-1;
+       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);
 
-static int setup_mapping(const char *cipher, const char *name,
-                        int bsize, struct volume_key *vk,
-                        unsigned int sector, size_t srcLength,
-                        int mode, struct crypt_device *ctx)
+       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 int LUKS_endec_template(char *src, size_t srcLength,
+                              const char *cipher, const char *cipher_mode,
+                              struct volume_key *vk,
+                              unsigned int sector,
+                              ssize_t (*func)(int, size_t, size_t, void *, size_t),
+                              int mode,
+                              struct crypt_device *ctx)
 {
-       struct device *device = crypt_metadata_device(ctx);
+       char name[PATH_MAX], path[PATH_MAX];
+       char cipher_spec[MAX_CIPHER_LEN * 3];
        struct crypt_dm_active_device dmd = {
-               .target = DM_CRYPT,
-               .uuid   = NULL,
-               .size   = round_up_modulo(srcLength, bsize) / SECTOR_SIZE,
-               .flags  = CRYPT_ACTIVATE_PRIVATE,
-               .data_device = device,
-               .u.crypt = {
-                       .cipher = cipher,
-                       .vk     = vk,
-                       .offset = sector,
-                       .iv_offset = 0,
-               }
+               .flags = CRYPT_ACTIVATE_PRIVATE,
        };
-       int r;
+       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;
 
-       r = device_block_adjust(ctx, dmd.data_device, DEV_OK,
-                               dmd.u.crypt.offset, &dmd.size, &dmd.flags);
-       if (r < 0)
-               return r;
+       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 (mode != O_RDONLY && dmd.flags & CRYPT_ACTIVATE_READONLY) {
-               log_err(ctx, _("Cannot write to device %s, permission denied.\n"),
-                       device_path(device));
+               log_err(ctx, _("Cannot write to device %s, permission denied."),
+                       device_path(crypt_metadata_device(ctx)));
                return -EACCES;
        }
-       cleaner_size = dmd.size;
-       return dm_create_device(ctx, 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(NULL, cleaner_name, 1, cleaner_size);
 
-       signal(SIGINT, SIG_DFL);
-       kill(getpid(), SIGINT);
-}
-
-static const char *_error_hint(char *cipherMode, size_t keyLength)
-{
-       const char *hint= "";
+       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;
 
-       if (!strncmp(cipherMode, "xts", 3) && (keyLength != 256 && keyLength != 512))
-               hint = _("Key size in XTS mode must be 256 or 512 bits.\n");
-
-       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,
-                              struct volume_key *vk,
-                              unsigned int sector,
-                              ssize_t (*func)(int, int, 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;
-       int bsize = device_block_size(crypt_metadata_device(ctx));
-
-       if(dmDir == NULL) {
-               log_err(ctx, _("Failed to obtain device mapper directory."));
-               return -1;
-       }
-       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, bsize, vk, sector, srcLength, mode, ctx);
-       if(r < 0) {
+       r = dm_create_device(ctx, name, "TEMP", &dmd);
+       if (r < 0) {
                if (r != -EACCES && r != -ENOTSUP)
-                       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_path(crypt_metadata_device(ctx)), dmCipherSpec,
-                       _error_hint(hdr->cipherMode, vk->keylength * 8));
+                       _error_hint(ctx, device_path(crypt_metadata_device(ctx)),
+                                   cipher, cipher_mode, vk->keylength * 8);
                r = -EIO;
-               goto out1;
+               goto out;
        }
+       remove_dev = 1;
 
-       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"));
+       devfd = open(path, mode | O_DIRECT | O_SYNC);
+       if (devfd == -1) {
+               log_err(ctx, _("Failed to open temporary keystore device."));
                r = -EIO;
-               goto out2;
+               goto out;
        }
 
-       r = func(devfd, bsize, src, srcLength);
-       if(r < 0) {
-               log_err(ctx, _("Failed to access temporary keystore device.\n"));
+       r = func(devfd, bsize, alignment, src, srcLength);
+       if (r < 0) {
+               log_err(ctx, _("Failed to access temporary keystore device."));
                r = -EIO;
-               goto out3;
-       }
-
-       r = 0;
- out3:
-       close(devfd);
-       devfd = -1;
- out2:
-       dm_remove_device(ctx, cleaner_name, 1, cleaner_size);
- out1:
-       signal(SIGINT, SIG_DFL);
-       cleaner_name = NULL;
-       cleaner_size = 0;
-       free(dmCipherSpec);
-       free(fullpath);
-       free(name);
+       } 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,
                            unsigned int sector,
                            struct crypt_device *ctx)
 {
-       return LUKS_endec_template(src, srcLength, hdr, vk, 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,
                              unsigned int sector,
                              struct crypt_device *ctx)
 {
-       return LUKS_endec_template(dst, dstLength, hdr, vk, 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;
 }