/usr/include/botan-2/botan/xmss_privatekey.h is in libbotan-2-dev 2.4.0-5ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 | /*
* XMSS_PrivateKey.h
* (C) 2016,2017 Matthias Gierlings
*
* Botan is released under the Simplified BSD License (see license.txt)
**/
#ifndef BOTAN_XMSS_PRIVATEKEY_H_
#define BOTAN_XMSS_PRIVATEKEY_H_
#include <cstddef>
#include <iterator>
#include <memory>
#include <botan/alg_id.h>
#include <botan/exceptn.h>
#include <botan/pk_keys.h>
#include <botan/types.h>
#include <botan/xmss_parameters.h>
#include <botan/xmss_publickey.h>
#include <botan/atomic.h>
#include <botan/xmss_common_ops.h>
#include <botan/xmss_wots_privatekey.h>
#include <botan/xmss_index_registry.h>
namespace Botan {
/**
* An XMSS: Extended Hash-Based Signature private key.
* The XMSS private key does not support the X509 and PKCS7 standard. Instead
* the raw format described in [1] is used.
*
* [1] XMSS: Extended Hash-Based Signatures,
* draft-itrf-cfrg-xmss-hash-based-signatures-06
* Release: July 2016.
* https://datatracker.ietf.org/doc/
* draft-irtf-cfrg-xmss-hash-based-signatures/?include_text=1
**/
class BOTAN_PUBLIC_API(2,0) XMSS_PrivateKey final : public virtual XMSS_PublicKey,
public XMSS_Common_Ops,
public virtual Private_Key
{
public:
/**
* Creates a new XMSS private key for the chosen XMSS signature method.
* New seeds for public/private key and pseudo random function input are
* generated using the provided RNG. The appropriate WOTS signature method
* will be automatically set based on the chosen XMSS signature method.
*
* @param xmss_algo_id Identifier for the selected XMSS signature method.
* @param rng A random number generator to use for key generation.
**/
XMSS_PrivateKey(XMSS_Parameters::xmss_algorithm_t xmss_algo_id,
RandomNumberGenerator& rng);
/**
* Creates an XMSS_PrivateKey from a byte sequence produced by
* raw_private_key().
*
* @param raw_key An XMSS private key serialized using raw_private_key().
**/
XMSS_PrivateKey(const secure_vector<uint8_t>& raw_key);
/**
* Creates a new XMSS private key for the chosen XMSS signature method
* using precomputed seeds for public/private keys and pseudo random
* function input. The appropriate WOTS signature method will be
* automatically set, based on the chosen XMSS signature method.
*
* @param xmss_algo_id Identifier for the selected XMSS signature method.
* @param idx_leaf Index of the next unused leaf.
* @param wots_priv_seed A seed to generate a Winternitz-One-Time-
* Signature private key from.
* @param prf a secret n-byte key sourced from a secure source
* of uniformly random data.
* @param root Root node of the binary hash tree.
* @param public_seed The public seed.
**/
XMSS_PrivateKey(XMSS_Parameters::xmss_algorithm_t xmss_algo_id,
size_t idx_leaf,
const secure_vector<uint8_t>& wots_priv_seed,
const secure_vector<uint8_t>& prf,
const secure_vector<uint8_t>& root,
const secure_vector<uint8_t>& public_seed)
: XMSS_PublicKey(xmss_algo_id, root, public_seed),
XMSS_Common_Ops(xmss_algo_id),
m_wots_priv_key(XMSS_PublicKey::m_xmss_params.ots_oid(),
public_seed,
wots_priv_seed),
m_prf(prf),
m_index_reg(XMSS_Index_Registry::get_instance())
{
set_unused_leaf_index(idx_leaf);
}
/**
* Retrieves the last unused leaf index of the private key. Reusing a leaf
* by utilizing leaf indices lower than the last unused leaf index will
* compromise security.
*
* @return Index of the last unused leaf.
**/
size_t unused_leaf_index() const
{
return *recover_global_leaf_index();
}
/**
* Sets the last unused leaf index of the private key. The leaf index
* will be updated automatically during every signing operation, and
* should not be set manually.
*
* @param idx Index of the last unused leaf.
**/
void set_unused_leaf_index(size_t idx)
{
if(idx >= (1ull << (XMSS_PublicKey::m_xmss_params.tree_height() - 1)))
{
throw Integrity_Failure("XMSS private key leaf index out of "
"bounds.");
}
else
{
std::atomic<size_t>& index =
static_cast<std::atomic<size_t>&>(*recover_global_leaf_index());
size_t current = 0;
do
{
current = index.load();
if(current > idx)
{ return; }
}
while(!index.compare_exchange_strong(current, idx));
}
}
size_t reserve_unused_leaf_index()
{
size_t idx = (static_cast<std::atomic<size_t>&>(
*recover_global_leaf_index())).fetch_add(1);
if(idx >= (1ull << (XMSS_PublicKey::m_xmss_params.tree_height() - 1)))
{
throw Integrity_Failure("XMSS private key, one time signatures "
"exhausted.");
}
return idx;
}
/**
* Winternitz One Time Signature Scheme key utilized for signing
* operations.
*
* @return WOTS+ private key.
**/
const XMSS_WOTS_PrivateKey& wots_private_key() const
{
return m_wots_priv_key;
}
/**
* Winternitz One Time Signature Scheme key utilized for signing
* operations.
*
* @return WOTS+ private key.
**/
XMSS_WOTS_PrivateKey& wots_private_key()
{
return m_wots_priv_key;
}
const secure_vector<uint8_t>& prf() const
{
return m_prf;
}
secure_vector<uint8_t>& prf()
{
return m_prf;
}
void set_public_seed(
const secure_vector<uint8_t>& public_seed) override
{
m_public_seed = public_seed;
m_wots_priv_key.set_public_seed(public_seed);
}
void set_public_seed(secure_vector<uint8_t>&& public_seed) override
{
m_public_seed = std::move(public_seed);
m_wots_priv_key.set_public_seed(m_public_seed);
}
const secure_vector<uint8_t>& public_seed() const override
{
return m_public_seed;
}
std::unique_ptr<PK_Ops::Signature>
create_signature_op(RandomNumberGenerator&,
const std::string&,
const std::string& provider) const override;
secure_vector<uint8_t> private_key_bits() const override
{
return raw_private_key();
}
size_t size() const override
{
return XMSS_PublicKey::size() +
sizeof(uint64_t) +
2 * XMSS_PublicKey::m_xmss_params.element_size();
}
/**
* Generates a non standartized byte sequence representing the XMSS
* private key.
*
* @return byte sequence consisting of the following elements in order:
* 4-byte OID, n-byte root node, n-byte public seed,
* 8-byte unused leaf index, n-byte prf seed, n-byte private seed.
**/
secure_vector<uint8_t> raw_private_key() const;
/**
* Algorithm 9: "treeHash"
* Computes the internal n-byte nodes of a Merkle tree.
*
* @param start_idx The start index.
* @param target_node_height Height of the target node.
* @param adrs Address of the tree containing the target node.
*
* @return The root node of a tree of height target_node height with the
* leftmost leaf being the hash of the WOTS+ pk with index
* start_idx.
**/
secure_vector<uint8_t> tree_hash(
size_t start_idx,
size_t target_node_height,
XMSS_Address& adrs);
private:
/**
* Fetches shared unused leaf index from the index registry
**/
std::shared_ptr<Atomic<size_t>> recover_global_leaf_index() const;
inline void tree_hash_subtree(secure_vector<uint8_t>& result,
size_t start_idx,
size_t target_node_height,
XMSS_Address& adrs)
{
return tree_hash_subtree(result, start_idx, target_node_height, adrs, m_hash);
}
/**
* Helper for multithreaded tree hashing.
*/
void tree_hash_subtree(secure_vector<uint8_t>& result,
size_t start_idx,
size_t target_node_height,
XMSS_Address& adrs,
XMSS_Hash& hash);
XMSS_WOTS_PrivateKey m_wots_priv_key;
secure_vector<uint8_t> m_prf;
XMSS_Index_Registry& m_index_reg;
};
}
#endif
|