/src/botan/src/lib/pubkey/xmss/xmss_common_ops.cpp
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * XMSS Common Ops |
3 | | * Operations shared by XMSS signature generation and verification operations. |
4 | | * (C) 2016,2017 Matthias Gierlings |
5 | | * |
6 | | * Botan is released under the Simplified BSD License (see license.txt) |
7 | | **/ |
8 | | |
9 | | #include <botan/internal/xmss_common_ops.h> |
10 | | #include <botan/xmss_hash.h> |
11 | | |
12 | | namespace Botan { |
13 | | |
14 | | void |
15 | | XMSS_Common_Ops::randomize_tree_hash(secure_vector<uint8_t>& result, |
16 | | const secure_vector<uint8_t>& left, |
17 | | const secure_vector<uint8_t>& right, |
18 | | XMSS_Address& adrs, |
19 | | const secure_vector<uint8_t>& seed, |
20 | | XMSS_Hash& hash, |
21 | | const XMSS_Parameters& params) |
22 | 0 | { |
23 | 0 | adrs.set_key_mask_mode(XMSS_Address::Key_Mask::Key_Mode); |
24 | 0 | secure_vector<uint8_t> key { hash.prf(seed, adrs.bytes()) }; |
25 | |
|
26 | 0 | adrs.set_key_mask_mode(XMSS_Address::Key_Mask::Mask_MSB_Mode); |
27 | 0 | secure_vector<uint8_t> bitmask_l { hash.prf(seed, adrs.bytes()) }; |
28 | |
|
29 | 0 | adrs.set_key_mask_mode(XMSS_Address::Key_Mask::Mask_LSB_Mode); |
30 | 0 | secure_vector<uint8_t> bitmask_r { hash.prf(seed, adrs.bytes()) }; |
31 | |
|
32 | 0 | BOTAN_ASSERT(bitmask_l.size() == left.size() && |
33 | 0 | bitmask_r.size() == right.size(), |
34 | 0 | "Bitmask size doesn't match node size."); |
35 | |
|
36 | 0 | secure_vector<uint8_t> concat_xor(params.element_size() * 2); |
37 | 0 | for(size_t i = 0; i < left.size(); i++) |
38 | 0 | { |
39 | 0 | concat_xor[i] = left[i] ^ bitmask_l[i]; |
40 | 0 | concat_xor[i + left.size()] = right[i] ^ bitmask_r[i]; |
41 | 0 | } |
42 | |
|
43 | 0 | hash.h(result, key, concat_xor); |
44 | 0 | } |
45 | | |
46 | | |
47 | | void |
48 | | XMSS_Common_Ops::create_l_tree(secure_vector<uint8_t>& result, |
49 | | wots_keysig_t pk, |
50 | | XMSS_Address& adrs, |
51 | | const secure_vector<uint8_t>& seed, |
52 | | XMSS_Hash& hash, |
53 | | const XMSS_Parameters& params) |
54 | 0 | { |
55 | 0 | size_t l = params.len(); |
56 | 0 | adrs.set_tree_height(0); |
57 | |
|
58 | 0 | while(l > 1) |
59 | 0 | { |
60 | 0 | for(size_t i = 0; i < l >> 1; i++) |
61 | 0 | { |
62 | 0 | adrs.set_tree_index(static_cast<uint32_t>(i)); |
63 | 0 | randomize_tree_hash(pk[i], pk[2 * i], pk[2 * i + 1], adrs, seed, hash, params); |
64 | 0 | } |
65 | 0 | if(l & 0x01) |
66 | 0 | { |
67 | 0 | pk[l >> 1] = pk[l - 1]; |
68 | 0 | } |
69 | 0 | l = (l >> 1) + (l & 0x01); |
70 | 0 | adrs.set_tree_height(adrs.get_tree_height() + 1); |
71 | 0 | } |
72 | 0 | result = pk[0]; |
73 | 0 | } |
74 | | |
75 | | } |