| /* Copyright (c) 2014 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| * |
| * Key unpacking functions |
| */ |
| |
| #include "2sysincludes.h" |
| #include "2rsa.h" |
| #include "vb2_common.h" |
| |
| const uint8_t *vb2_packed_key_data(const struct vb2_packed_key *key) |
| { |
| return (const uint8_t *)key + key->key_offset; |
| } |
| |
| int vb2_verify_packed_key_inside(const void *parent, |
| uint32_t parent_size, |
| const struct vb2_packed_key *key) |
| { |
| return vb2_verify_member_inside(parent, parent_size, |
| key, sizeof(*key), |
| key->key_offset, key->key_size); |
| } |
| |
| test_mockable |
| int vb2_unpack_key_buffer(struct vb2_public_key *key, |
| const uint8_t *buf, |
| uint32_t size) |
| { |
| const struct vb2_packed_key *packed_key = |
| (const struct vb2_packed_key *)buf; |
| const uint32_t *buf32; |
| uint32_t expected_key_size; |
| int rv; |
| |
| /* Make sure passed buffer is big enough for the packed key */ |
| rv = vb2_verify_packed_key_inside(buf, size, packed_key); |
| if (rv) |
| return rv; |
| |
| /* Unpack key algorithm */ |
| key->sig_alg = vb2_crypto_to_signature(packed_key->algorithm); |
| if (key->sig_alg == VB2_SIG_INVALID) { |
| VB2_DEBUG("Unsupported signature algorithm.\n"); |
| return VB2_ERROR_UNPACK_KEY_SIG_ALGORITHM; |
| } |
| |
| key->hash_alg = vb2_crypto_to_hash(packed_key->algorithm); |
| if (key->hash_alg == VB2_HASH_INVALID) { |
| VB2_DEBUG("Unsupported hash algorithm.\n"); |
| return VB2_ERROR_UNPACK_KEY_HASH_ALGORITHM; |
| } |
| |
| expected_key_size = vb2_packed_key_size(key->sig_alg); |
| if (!expected_key_size || expected_key_size != packed_key->key_size) { |
| VB2_DEBUG("Wrong key size for algorithm\n"); |
| return VB2_ERROR_UNPACK_KEY_SIZE; |
| } |
| |
| /* Make sure source buffer is 32-bit aligned */ |
| buf32 = (const uint32_t *)vb2_packed_key_data(packed_key); |
| if (!vb2_aligned(buf32, sizeof(uint32_t))) |
| return VB2_ERROR_UNPACK_KEY_ALIGN; |
| |
| /* Sanity check key array size */ |
| key->arrsize = buf32[0]; |
| if (key->arrsize * sizeof(uint32_t) != vb2_rsa_sig_size(key->sig_alg)) |
| return VB2_ERROR_UNPACK_KEY_ARRAY_SIZE; |
| |
| key->n0inv = buf32[1]; |
| |
| /* Arrays point inside the key data */ |
| key->n = buf32 + 2; |
| key->rr = buf32 + 2 + key->arrsize; |
| |
| return VB2_SUCCESS; |
| } |
| |
| int vb2_unpack_key(struct vb2_public_key *key, |
| const struct vb2_packed_key *packed_key) |
| { |
| if (!packed_key) |
| return VB2_ERROR_UNPACK_KEY_BUFFER; |
| |
| return vb2_unpack_key_buffer(key, |
| (const uint8_t *)packed_key, |
| packed_key->key_offset + |
| packed_key->key_size); |
| } |