1 /*
2 * Copyright 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "kdf.h"
18
19 namespace keymaster {
20
Kdf()21 Kdf::Kdf() : is_initialized_(false) {}
22
Init(keymaster_digest_t digest_type,const uint8_t * secret,size_t secret_len,const uint8_t * salt,size_t salt_len)23 bool Kdf::Init(keymaster_digest_t digest_type, const uint8_t* secret, size_t secret_len,
24 const uint8_t* salt, size_t salt_len) {
25 is_initialized_ = false;
26
27 switch (digest_type) {
28 case KM_DIGEST_SHA1:
29 digest_size_ = 20;
30 digest_type_ = digest_type;
31 break;
32 case KM_DIGEST_SHA_2_256:
33 digest_size_ = 32;
34 digest_type_ = digest_type;
35 break;
36 default:
37 return false;
38 }
39
40 if (!secret || secret_len == 0)
41 return false;
42
43 secret_key_len_ = secret_len;
44 secret_key_.reset(dup_buffer(secret, secret_len));
45 if (!secret_key_.get())
46 return false;
47
48 salt_len_ = salt_len;
49 if (salt && salt_len > 0) {
50 salt_.reset(dup_buffer(salt, salt_len));
51 if (!salt_.get())
52 return false;
53 } else {
54 salt_.reset();
55 }
56
57 is_initialized_ = true;
58 return true;
59 }
60
Uint32ToBigEndianByteArray(uint32_t number,uint8_t * output)61 bool Kdf::Uint32ToBigEndianByteArray(uint32_t number, uint8_t* output) {
62 if (!output)
63 return false;
64
65 output[0] = (number >> 24) & 0xff;
66 output[1] = (number >> 16) & 0xff;
67 output[2] = (number >> 8) & 0xff;
68 output[3] = (number)&0xff;
69 return true;
70 }
71
72 } // namespace keymaster
73