cryptenroll: disable loading public key if --tpm2-public-key= is empty

This commit is contained in:
Sam Leonard 2024-04-26 13:35:05 +01:00 committed by Luca Boccassi
parent 70246e37bc
commit 03e3b2672b
3 changed files with 32 additions and 20 deletions

View file

@ -250,6 +250,7 @@ int enroll_tpm2(struct crypt_device *cd,
Tpm2PCRValue *hash_pcr_values,
size_t n_hash_pcr_values,
const char *pubkey_path,
bool load_pubkey,
uint32_t pubkey_pcr_mask,
const char *signature_path,
bool use_pin,
@ -306,25 +307,27 @@ int enroll_tpm2(struct crypt_device *cd,
}
TPM2B_PUBLIC public = {};
r = tpm2_load_pcr_public_key(pubkey_path, &pubkey.iov_base, &pubkey.iov_len);
if (r < 0) {
if (pubkey_path || signature_path || r != -ENOENT)
return log_error_errno(r, "Failed to read TPM PCR public key: %m");
if (load_pubkey) {
r = tpm2_load_pcr_public_key(pubkey_path, &pubkey.iov_base, &pubkey.iov_len);
if (r < 0) {
if (pubkey_path || signature_path || r != -ENOENT)
return log_error_errno(r, "Failed to read TPM PCR public key: %m");
log_debug_errno(r, "Failed to read TPM2 PCR public key, proceeding without: %m");
pubkey_pcr_mask = 0;
} else {
r = tpm2_tpm2b_public_from_pem(pubkey.iov_base, pubkey.iov_len, &public);
if (r < 0)
return log_error_errno(r, "Could not convert public key to TPM2B_PUBLIC: %m");
if (signature_path) {
/* Also try to load the signature JSON object, to verify that our enrollment will work.
* This is optional however, skip it if it's not explicitly provided. */
r = tpm2_load_pcr_signature(signature_path, &signature_json);
log_debug_errno(r, "Failed to read TPM2 PCR public key, proceeding without: %m");
pubkey_pcr_mask = 0;
} else {
r = tpm2_tpm2b_public_from_pem(pubkey.iov_base, pubkey.iov_len, &public);
if (r < 0)
return log_debug_errno(r, "Failed to read TPM PCR signature: %m");
return log_error_errno(r, "Could not convert public key to TPM2B_PUBLIC: %m");
if (signature_path) {
/* Also try to load the signature JSON object, to verify that our enrollment will work.
* This is optional however, skip it if it's not explicitly provided. */
r = tpm2_load_pcr_signature(signature_path, &signature_json);
if (r < 0)
return log_debug_errno(r, "Failed to read TPM PCR signature: %m");
}
}
}

View file

@ -9,14 +9,14 @@
#if HAVE_TPM2
int load_volume_key_tpm2(struct crypt_device *cd, const char *cd_node, const char *device, void *ret_vk, size_t *ret_vks);
int enroll_tpm2(struct crypt_device *cd, const void *volume_key, size_t volume_key_size, const char *device, uint32_t seal_key_handle, const char *device_key, Tpm2PCRValue *hash_pcrs, size_t n_hash_pcrs, const char *pubkey_path, uint32_t pubkey_pcr_mask, const char *signature_path, bool use_pin, const char *pcrlock_path, int *ret_slot_to_wipe);
int enroll_tpm2(struct crypt_device *cd, const void *volume_key, size_t volume_key_size, const char *device, uint32_t seal_key_handle, const char *device_key, Tpm2PCRValue *hash_pcr_values, size_t n_hash_pcr_values, const char *pubkey_path, bool disable_loading_pubkey, uint32_t pubkey_pcr_mask, const char *signature_path, bool use_pin, const char *pcrlock_path, int *ret_slot_to_wipe);
#else
static inline int load_volume_key_tpm2(struct crypt_device *cd, const char *cd_node, const char *device, void *ret_vk, size_t *ret_vks) {
return log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
"TPM2 unlocking not supported.");
}
static inline int enroll_tpm2(struct crypt_device *cd, const void *volume_key, size_t volume_key_size, const char *device, uint32_t seal_key_handle, const char *device_key, Tpm2PCRValue *hash_pcrs, size_t n_hash_pcrs, const char *pubkey_path, uint32_t pubkey_pcr_mask, const char *signature_path, bool use_pin, const char *pcrlock_path, int *slot_to_wipe) {
static inline int enroll_tpm2(struct crypt_device *cd, const void *volume_key, size_t volume_key_size, const char *device, uint32_t seal_key_handle, const char *device_key, Tpm2PCRValue *hash_pcr_values, size_t n_hash_pcr_values, const char *pubkey_path, bool disable_loading_pubkey, uint32_t pubkey_pcr_mask, const char *signature_path, bool use_pin, const char *pcrlock_path, int *ret_slot_to_wipe) {
return log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
"TPM2 key enrollment not supported.");
}

View file

@ -46,6 +46,7 @@ static Tpm2PCRValue *arg_tpm2_hash_pcr_values = NULL;
static size_t arg_tpm2_n_hash_pcr_values = 0;
static bool arg_tpm2_pin = false;
static char *arg_tpm2_public_key = NULL;
static bool arg_tpm2_load_public_key = true;
static uint32_t arg_tpm2_public_key_pcr_mask = 0;
static char *arg_tpm2_signature = NULL;
static char *arg_tpm2_pcrlock = NULL;
@ -498,9 +499,17 @@ static int parse_argv(int argc, char *argv[]) {
break;
case ARG_TPM2_PUBLIC_KEY:
/* an empty argument disables loading a public key */
if (isempty(optarg)) {
arg_tpm2_load_public_key = false;
arg_tpm2_public_key = mfree(arg_tpm2_public_key);
break;
}
r = parse_path_argument(optarg, /* suppress_root= */ false, &arg_tpm2_public_key);
if (r < 0)
return r;
arg_tpm2_load_public_key = true;
break;
@ -834,7 +843,7 @@ static int run(int argc, char *argv[]) {
break;
case ENROLL_TPM2:
slot = enroll_tpm2(cd, vk, vks, arg_tpm2_device, arg_tpm2_seal_key_handle, arg_tpm2_device_key, arg_tpm2_hash_pcr_values, arg_tpm2_n_hash_pcr_values, arg_tpm2_public_key, arg_tpm2_public_key_pcr_mask, arg_tpm2_signature, arg_tpm2_pin, arg_tpm2_pcrlock, &slot_to_wipe);
slot = enroll_tpm2(cd, vk, vks, arg_tpm2_device, arg_tpm2_seal_key_handle, arg_tpm2_device_key, arg_tpm2_hash_pcr_values, arg_tpm2_n_hash_pcr_values, arg_tpm2_public_key, arg_tpm2_load_public_key, arg_tpm2_public_key_pcr_mask, arg_tpm2_signature, arg_tpm2_pin, arg_tpm2_pcrlock, &slot_to_wipe);
if (slot >= 0 && slot_to_wipe >= 0) {
/* Updating PIN on an existing enrollment */