diff options
Diffstat (limited to 'lib/keyslot_context.c')
| -rw-r--r-- | lib/keyslot_context.c | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/lib/keyslot_context.c b/lib/keyslot_context.c new file mode 100644 index 0000000..89bd433 --- /dev/null +++ b/lib/keyslot_context.c @@ -0,0 +1,488 @@ +/* + * LUKS - Linux Unified Key Setup, keyslot unlock helpers + * + * Copyright (C) 2022-2023 Red Hat, Inc. All rights reserved. + * Copyright (C) 2022-2023 Ondrej Kozina + * + * 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 <errno.h> + +#include "luks1/luks.h" +#include "luks2/luks2.h" +#include "keyslot_context.h" + +static int get_luks2_key_by_passphrase(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + int segment, + struct volume_key **r_vk) +{ + int r; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_PASSPHRASE); + assert(r_vk); + + r = LUKS2_keyslot_open(cd, keyslot, segment, kc->u.p.passphrase, kc->u.p.passphrase_size, r_vk); + if (r < 0) + kc->error = r; + + return r; +} + +static int get_luks1_volume_key_by_passphrase(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + struct volume_key **r_vk) +{ + int r; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_PASSPHRASE); + assert(r_vk); + + r = LUKS_open_key_with_hdr(keyslot, kc->u.p.passphrase, kc->u.p.passphrase_size, + crypt_get_hdr(cd, CRYPT_LUKS1), r_vk, cd); + if (r < 0) + kc->error = r; + + return r; +} + +static int get_luks2_volume_key_by_passphrase(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + struct volume_key **r_vk) +{ + return get_luks2_key_by_passphrase(cd, kc, keyslot, CRYPT_DEFAULT_SEGMENT, r_vk); +} + +static int get_passphrase_by_passphrase(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + const char **r_passphrase, + size_t *r_passphrase_size) +{ + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_PASSPHRASE); + assert(r_passphrase); + assert(r_passphrase_size); + + *r_passphrase = kc->u.p.passphrase; + *r_passphrase_size = kc->u.p.passphrase_size; + + return 0; +} + +static int get_passphrase_by_keyfile(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + const char **r_passphrase, + size_t *r_passphrase_size) +{ + int r; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_KEYFILE); + assert(r_passphrase); + assert(r_passphrase_size); + + if (!kc->i_passphrase) { + r = crypt_keyfile_device_read(cd, kc->u.kf.keyfile, + &kc->i_passphrase, &kc->i_passphrase_size, + kc->u.kf.keyfile_offset, kc->u.kf.keyfile_size, 0); + if (r < 0) { + kc->error = r; + return r; + } + } + + *r_passphrase = kc->i_passphrase; + *r_passphrase_size = kc->i_passphrase_size; + + return 0; +} + +static int get_luks2_key_by_keyfile(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + int segment, + struct volume_key **r_vk) +{ + int r; + const char *passphrase; + size_t passphrase_size; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_KEYFILE); + assert(r_vk); + + r = get_passphrase_by_keyfile(cd, kc, &passphrase, &passphrase_size); + if (r) + return r; + + r = LUKS2_keyslot_open(cd, keyslot, segment, passphrase, passphrase_size, r_vk); + if (r < 0) + kc->error = r; + + return r; +} + +static int get_luks2_volume_key_by_keyfile(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + struct volume_key **r_vk) +{ + return get_luks2_key_by_keyfile(cd, kc, keyslot, CRYPT_DEFAULT_SEGMENT, r_vk); +} + +static int get_luks1_volume_key_by_keyfile(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot, + struct volume_key **r_vk) +{ + int r; + const char *passphrase; + size_t passphrase_size; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_KEYFILE); + assert(r_vk); + + r = get_passphrase_by_keyfile(cd, kc, &passphrase, &passphrase_size); + if (r) + return r; + + r = LUKS_open_key_with_hdr(keyslot, passphrase, passphrase_size, + crypt_get_hdr(cd, CRYPT_LUKS1), r_vk, cd); + if (r < 0) + kc->error = r; + + return r; +} + +static int get_key_by_key(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot __attribute__((unused)), + int segment __attribute__((unused)), + struct volume_key **r_vk) +{ + assert(kc && kc->type == CRYPT_KC_TYPE_KEY); + assert(r_vk); + + if (!kc->u.k.volume_key) { + kc->error = -ENOENT; + return kc->error; + } + + *r_vk = crypt_alloc_volume_key(kc->u.k.volume_key_size, kc->u.k.volume_key); + if (!*r_vk) { + kc->error = -ENOMEM; + return kc->error; + } + + return 0; +} + +static int get_volume_key_by_key(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot __attribute__((unused)), + struct volume_key **r_vk) +{ + return get_key_by_key(cd, kc, -2 /* unused */, -2 /* unused */, r_vk); +} + +static int get_luks2_key_by_token(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot __attribute__((unused)), + int segment, + struct volume_key **r_vk) +{ + int r; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_TOKEN); + assert(r_vk); + + r = LUKS2_token_unlock_key(cd, crypt_get_hdr(cd, CRYPT_LUKS2), kc->u.t.id, kc->u.t.type, + kc->u.t.pin, kc->u.t.pin_size, segment, kc->u.t.usrptr, r_vk); + if (r < 0) + kc->error = r; + + return r; +} + +static int get_luks2_volume_key_by_token(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + int keyslot __attribute__((unused)), + struct volume_key **r_vk) +{ + return get_luks2_key_by_token(cd, kc, -2 /* unused */, CRYPT_DEFAULT_SEGMENT, r_vk); +} + +static int get_passphrase_by_token(struct crypt_device *cd, + struct crypt_keyslot_context *kc, + const char **r_passphrase, + size_t *r_passphrase_size) +{ + int r; + + assert(cd); + assert(kc && kc->type == CRYPT_KC_TYPE_TOKEN); + assert(r_passphrase); + assert(r_passphrase_size); + + if (!kc->i_passphrase) { + r = LUKS2_token_unlock_passphrase(cd, crypt_get_hdr(cd, CRYPT_LUKS2), kc->u.t.id, + kc->u.t.type, kc->u.t.pin, kc->u.t.pin_size, + kc->u.t.usrptr, &kc->i_passphrase, &kc->i_passphrase_size); + if (r < 0) { + kc->error = r; + return r; + } + kc->u.t.id = r; + } + + *r_passphrase = kc->i_passphrase; + *r_passphrase_size = kc->i_passphrase_size; + + return kc->u.t.id; +} + +static void unlock_method_init_internal(struct crypt_keyslot_context *kc) +{ + assert(kc); + + kc->error = 0; + kc->i_passphrase = NULL; + kc->i_passphrase_size = 0; +} + +void crypt_keyslot_unlock_by_key_init_internal(struct crypt_keyslot_context *kc, + const char *volume_key, + size_t volume_key_size) +{ + assert(kc); + + kc->type = CRYPT_KC_TYPE_KEY; + kc->u.k.volume_key = volume_key; + kc->u.k.volume_key_size = volume_key_size; + kc->get_luks2_key = get_key_by_key; + kc->get_luks2_volume_key = get_volume_key_by_key; + kc->get_luks1_volume_key = get_volume_key_by_key; + kc->get_passphrase = NULL; /* keyslot key context does not provide passphrase */ + unlock_method_init_internal(kc); +} + +void crypt_keyslot_unlock_by_passphrase_init_internal(struct crypt_keyslot_context *kc, + const char *passphrase, + size_t passphrase_size) +{ + assert(kc); + + kc->type = CRYPT_KC_TYPE_PASSPHRASE; + kc->u.p.passphrase = passphrase; + kc->u.p.passphrase_size = passphrase_size; + kc->get_luks2_key = get_luks2_key_by_passphrase; + kc->get_luks2_volume_key = get_luks2_volume_key_by_passphrase; + kc->get_luks1_volume_key = get_luks1_volume_key_by_passphrase; + kc->get_passphrase = get_passphrase_by_passphrase; + unlock_method_init_internal(kc); +} + +void crypt_keyslot_unlock_by_keyfile_init_internal(struct crypt_keyslot_context *kc, + const char *keyfile, + size_t keyfile_size, + uint64_t keyfile_offset) +{ + assert(kc); + + kc->type = CRYPT_KC_TYPE_KEYFILE; + kc->u.kf.keyfile = keyfile; + kc->u.kf.keyfile_size = keyfile_size; + kc->u.kf.keyfile_offset = keyfile_offset; + kc->get_luks2_key = get_luks2_key_by_keyfile; + kc->get_luks2_volume_key = get_luks2_volume_key_by_keyfile; + kc->get_luks1_volume_key = get_luks1_volume_key_by_keyfile; + kc->get_passphrase = get_passphrase_by_keyfile; + unlock_method_init_internal(kc); +} + +void crypt_keyslot_unlock_by_token_init_internal(struct crypt_keyslot_context *kc, + int token, + const char *type, + const char *pin, + size_t pin_size, + void *usrptr) +{ + assert(kc); + + kc->type = CRYPT_KC_TYPE_TOKEN; + kc->u.t.id = token; + kc->u.t.type = type; + kc->u.t.pin = pin; + kc->u.t.pin_size = pin_size; + kc->u.t.usrptr = usrptr; + kc->get_luks2_key = get_luks2_key_by_token; + kc->get_luks2_volume_key = get_luks2_volume_key_by_token; + kc->get_luks1_volume_key = NULL; /* LUKS1 is not supported */ + kc->get_passphrase = get_passphrase_by_token; + unlock_method_init_internal(kc); +} + +void crypt_keyslot_context_destroy_internal(struct crypt_keyslot_context *kc) +{ + if (!kc) + return; + + crypt_safe_free(kc->i_passphrase); + kc->i_passphrase = NULL; + kc->i_passphrase_size = 0; +} + +void crypt_keyslot_context_free(struct crypt_keyslot_context *kc) +{ + crypt_keyslot_context_destroy_internal(kc); + free(kc); +} + +int crypt_keyslot_context_init_by_passphrase(struct crypt_device *cd, + const char *passphrase, + size_t passphrase_size, + struct crypt_keyslot_context **kc) +{ + struct crypt_keyslot_context *tmp; + + if (!kc || !passphrase) + return -EINVAL; + + tmp = malloc(sizeof(*tmp)); + if (!tmp) + return -ENOMEM; + + crypt_keyslot_unlock_by_passphrase_init_internal(tmp, passphrase, passphrase_size); + + *kc = tmp; + + return 0; +} + +int crypt_keyslot_context_init_by_keyfile(struct crypt_device *cd, + const char *keyfile, + size_t keyfile_size, + uint64_t keyfile_offset, + struct crypt_keyslot_context **kc) +{ + struct crypt_keyslot_context *tmp; + + if (!kc || !keyfile) + return -EINVAL; + + tmp = malloc(sizeof(*tmp)); + if (!tmp) + return -ENOMEM; + + crypt_keyslot_unlock_by_keyfile_init_internal(tmp, keyfile, keyfile_size, keyfile_offset); + + *kc = tmp; + + return 0; +} + +int crypt_keyslot_context_init_by_token(struct crypt_device *cd, + int token, + const char *type, + const char *pin, size_t pin_size, + void *usrptr, + struct crypt_keyslot_context **kc) +{ + struct crypt_keyslot_context *tmp; + + if (!kc || (token < 0 && token != CRYPT_ANY_TOKEN)) + return -EINVAL; + + tmp = malloc(sizeof(*tmp)); + if (!tmp) + return -ENOMEM; + + crypt_keyslot_unlock_by_token_init_internal(tmp, token, type, pin, pin_size, usrptr); + + *kc = tmp; + + return 0; +} + +int crypt_keyslot_context_init_by_volume_key(struct crypt_device *cd, + const char *volume_key, + size_t volume_key_size, + struct crypt_keyslot_context **kc) +{ + struct crypt_keyslot_context *tmp; + + if (!kc) + return -EINVAL; + + tmp = malloc(sizeof(*tmp)); + if (!tmp) + return -ENOMEM; + + crypt_keyslot_unlock_by_key_init_internal(tmp, volume_key, volume_key_size); + + *kc = tmp; + + return 0; +} + +int crypt_keyslot_context_get_error(struct crypt_keyslot_context *kc) +{ + return kc ? kc->error : -EINVAL; +} + +int crypt_keyslot_context_set_pin(struct crypt_device *cd, + const char *pin, size_t pin_size, + struct crypt_keyslot_context *kc) +{ + if (!kc || kc->type != CRYPT_KC_TYPE_TOKEN) + return -EINVAL; + + kc->u.t.pin = pin; + kc->u.t.pin_size = pin_size; + kc->error = 0; + + return 0; +} + +int crypt_keyslot_context_get_type(const struct crypt_keyslot_context *kc) +{ + return kc ? kc->type : -EINVAL; +} + +const char *keyslot_context_type_string(const struct crypt_keyslot_context *kc) +{ + assert(kc); + + switch (kc->type) { + case CRYPT_KC_TYPE_PASSPHRASE: + return "passphrase"; + case CRYPT_KC_TYPE_KEYFILE: + return "keyfile"; + case CRYPT_KC_TYPE_TOKEN: + return "token"; + case CRYPT_KC_TYPE_KEY: + return "key"; + default: + return "<unknown>"; + } +} |