diff --git a/security/keys/trusted-keys/trusted_dcp.c b/security/keys/trusted-keys/trusted_dcp.c index b0947f072a98..4edc5bbbcda3 100644 --- a/security/keys/trusted-keys/trusted_dcp.c +++ b/security/keys/trusted-keys/trusted_dcp.c @@ -186,20 +186,21 @@ static int do_aead_crypto(u8 *in, u8 *out, size_t len, u8 *key, u8 *nonce, return ret; } -static int decrypt_blob_key(u8 *key) +static int decrypt_blob_key(u8 *encrypted_key, u8 *plain_key) { - return do_dcp_crypto(key, key, false); + return do_dcp_crypto(encrypted_key, plain_key, false); } -static int encrypt_blob_key(u8 *key) +static int encrypt_blob_key(u8 *plain_key, u8 *encrypted_key) { - return do_dcp_crypto(key, key, true); + return do_dcp_crypto(plain_key, encrypted_key, true); } static int trusted_dcp_seal(struct trusted_key_payload *p, char *datablob) { struct dcp_blob_fmt *b = (struct dcp_blob_fmt *)p->blob; int blen, ret; + u8 plain_blob_key[AES_KEYSIZE_128]; blen = calc_blob_len(p->key_len); if (blen > MAX_BLOB_SIZE) @@ -207,30 +208,36 @@ static int trusted_dcp_seal(struct trusted_key_payload *p, char *datablob) b->fmt_version = DCP_BLOB_VERSION; get_random_bytes(b->nonce, AES_KEYSIZE_128); - get_random_bytes(b->blob_key, AES_KEYSIZE_128); + get_random_bytes(plain_blob_key, AES_KEYSIZE_128); - ret = do_aead_crypto(p->key, b->payload, p->key_len, b->blob_key, + ret = do_aead_crypto(p->key, b->payload, p->key_len, plain_blob_key, b->nonce, true); if (ret) { pr_err("Unable to encrypt blob payload: %i\n", ret); - return ret; + goto out; } - ret = encrypt_blob_key(b->blob_key); + ret = encrypt_blob_key(plain_blob_key, b->blob_key); if (ret) { pr_err("Unable to encrypt blob key: %i\n", ret); - return ret; + goto out; } put_unaligned_le32(p->key_len, &b->payload_len); p->blob_len = blen; - return 0; + ret = 0; + +out: + memzero_explicit(plain_blob_key, sizeof(plain_blob_key)); + + return ret; } static int trusted_dcp_unseal(struct trusted_key_payload *p, char *datablob) { struct dcp_blob_fmt *b = (struct dcp_blob_fmt *)p->blob; int blen, ret; + u8 plain_blob_key[AES_KEYSIZE_128]; if (b->fmt_version != DCP_BLOB_VERSION) { pr_err("DCP blob has bad version: %i, expected %i\n", @@ -248,14 +255,14 @@ static int trusted_dcp_unseal(struct trusted_key_payload *p, char *datablob) goto out; } - ret = decrypt_blob_key(b->blob_key); + ret = decrypt_blob_key(b->blob_key, plain_blob_key); if (ret) { pr_err("Unable to decrypt blob key: %i\n", ret); goto out; } ret = do_aead_crypto(b->payload, p->key, p->key_len + DCP_BLOB_AUTHLEN, - b->blob_key, b->nonce, false); + plain_blob_key, b->nonce, false); if (ret) { pr_err("Unwrap of DCP payload failed: %i\n", ret); goto out; @@ -263,6 +270,8 @@ static int trusted_dcp_unseal(struct trusted_key_payload *p, char *datablob) ret = 0; out: + memzero_explicit(plain_blob_key, sizeof(plain_blob_key)); + return ret; }