diff options
Diffstat (limited to 'src/cryptsetup/cryptsetup-tpm2.c')
| -rw-r--r-- | src/cryptsetup/cryptsetup-tpm2.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/src/cryptsetup/cryptsetup-tpm2.c b/src/cryptsetup/cryptsetup-tpm2.c index 838c02bfc9..2a8a38c593 100644 --- a/src/cryptsetup/cryptsetup-tpm2.c +++ b/src/cryptsetup/cryptsetup-tpm2.c @@ -9,6 +9,7 @@ #include "json.h" #include "parse-util.h" #include "random-util.h" +#include "sha256.h" #include "tpm2-util.h" static int get_pin(usec_t until, AskPasswordFlags ask_password_flags, bool headless, char **ret_pin_str) { @@ -69,6 +70,8 @@ int acquire_tpm2_key( size_t key_data_size, const void *policy_hash, size_t policy_hash_size, + const void *salt, + size_t salt_size, TPM2Flags flags, usec_t until, bool headless, @@ -140,7 +143,7 @@ int acquire_tpm2_key( ret_decrypted_key_size); for (int i = 5;; i--) { - _cleanup_(erase_and_freep) char *pin_str = NULL; + _cleanup_(erase_and_freep) char *pin_str = NULL, *b64_salted_pin = NULL; if (i <= 0) return -EACCES; @@ -149,13 +152,28 @@ int acquire_tpm2_key( if (r < 0) return r; + if (salt) { + uint8_t salted_pin[SHA256_DIGEST_SIZE] = {}; + CLEANUP_ERASE(salted_pin); + + r = tpm2_util_pbkdf2_hmac_sha256(pin_str, strlen(pin_str), salt, salt_size, salted_pin); + if (r < 0) + return log_error_errno(r, "Failed to perform PBKDF2: %m"); + + r = base64mem(salted_pin, sizeof(salted_pin), &b64_salted_pin); + if (r < 0) + return log_error_errno(r, "Failed to base64 encode salted pin: %m"); + } else + /* no salting needed, backwards compat with non-salted pins */ + b64_salted_pin = TAKE_PTR(pin_str); + r = tpm2_unseal(device, hash_pcr_mask, pcr_bank, pubkey, pubkey_size, pubkey_pcr_mask, signature_json, - pin_str, + b64_salted_pin, primary_alg, blob, blob_size, @@ -188,6 +206,8 @@ int find_tpm2_auto_data( size_t *ret_blob_size, void **ret_policy_hash, size_t *ret_policy_hash_size, + void **ret_salt, + size_t *ret_salt_size, TPM2Flags *ret_flags, int *ret_keyslot, int *ret_token) { @@ -197,9 +217,9 @@ int find_tpm2_auto_data( assert(cd); for (token = start_token; token < sym_crypt_token_max(CRYPT_LUKS2); token++) { - _cleanup_free_ void *blob = NULL, *policy_hash = NULL, *pubkey = NULL; + _cleanup_free_ void *blob = NULL, *policy_hash = NULL, *pubkey = NULL, *salt = NULL; _cleanup_(json_variant_unrefp) JsonVariant *v = NULL; - size_t blob_size, policy_hash_size, pubkey_size; + size_t blob_size, policy_hash_size, pubkey_size, salt_size = 0; uint32_t hash_pcr_mask, pubkey_pcr_mask; uint16_t pcr_bank, primary_alg; TPM2Flags flags; @@ -221,6 +241,7 @@ int find_tpm2_auto_data( &primary_alg, &blob, &blob_size, &policy_hash, &policy_hash_size, + &salt, &salt_size, &flags); if (r == -EUCLEAN) /* Gracefully handle issues in JSON fields not owned by us */ continue; @@ -243,6 +264,8 @@ int find_tpm2_auto_data( *ret_blob_size = blob_size; *ret_policy_hash = TAKE_PTR(policy_hash); *ret_policy_hash_size = policy_hash_size; + *ret_salt = TAKE_PTR(salt); + *ret_salt_size = salt_size; *ret_keyslot = keyslot; *ret_token = token; *ret_flags = flags; |