Botan 2.13.0 Crypto and TLS for C++11

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xmss_publickey.cpp
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1 /*
2 * XMSS Public Key
3 * An XMSS: Extended Hash-Based Siganture public key.
4 * The XMSS public key does not support the X509 standard. Instead the
5 * raw format described in [1] is used.
6 *
7 * [1] XMSS: Extended Hash-Based Signatures,
8 * Request for Comments: 8391
9 * Release: May 2018.
10 * https://datatracker.ietf.org/doc/rfc8391/
11 *
12 * (C) 2016,2017 Matthias Gierlings
13 *
14 * Botan is released under the Simplified BSD License (see license.txt)
15 **/
16
17 #include <botan/internal/xmss_verification_operation.h>
18 #include <botan/xmss_publickey.h>
19 #include <botan/der_enc.h>
20 #include <botan/ber_dec.h>
21
22 namespace Botan {
23
24 namespace {
25
26 // fall back to raw decoding for previous versions, which did not encode an OCTET STRING
27 std::vector<uint8_t> extract_raw_key(const std::vector<uint8_t>& key_bits)
28 {
29 std::vector<uint8_t> raw_key;
30 try
31 {
32 BER_Decoder(key_bits).decode(raw_key, OCTET_STRING);
33 }
34 catch(Decoding_Error&)
35 {
36 raw_key = key_bits;
37 }
38 return raw_key;
39 }
40
41 }
42
43 XMSS_PublicKey::XMSS_PublicKey(const std::vector<uint8_t>& key_bits)
44 : m_raw_key(extract_raw_key(key_bits)),
45 m_xmss_params(XMSS_PublicKey::deserialize_xmss_oid(m_raw_key)),
46 m_wots_params(m_xmss_params.ots_oid())
47 {
48 if(m_raw_key.size() < XMSS_PublicKey::size())
49 {
50 throw Decoding_Error("Invalid XMSS public key size detected");
51 }
52
53 // extract & copy root from raw key
54 m_root.clear();
55 m_root.reserve(m_xmss_params.element_size());
56 auto begin = m_raw_key.begin() + sizeof(uint32_t);
57 auto end = begin + m_xmss_params.element_size();
58 std::copy(begin, end, std::back_inserter(m_root));
59
60 // extract & copy public seed from raw key
61 begin = end;
62 end = begin + m_xmss_params.element_size();
63 m_public_seed.clear();
64 m_public_seed.reserve(m_xmss_params.element_size());
65 std::copy(begin, end, std::back_inserter(m_public_seed));
66 }
67
68 XMSS_Parameters::xmss_algorithm_t
69 XMSS_PublicKey::deserialize_xmss_oid(const std::vector<uint8_t>& raw_key)
70 {
71 if(raw_key.size() < 4)
72 {
73 throw Decoding_Error("XMSS signature OID missing.");
74 }
75
76 // extract and convert algorithm id to enum type
77 uint32_t raw_id = 0;
78 for(size_t i = 0; i < 4; i++)
79 { raw_id = ((raw_id << 8) | raw_key[i]); }
80
81 return static_cast<XMSS_Parameters::xmss_algorithm_t>(raw_id);
82 }
83
84 std::unique_ptr<PK_Ops::Verification>
85 XMSS_PublicKey::create_verification_op(const std::string&,
86 const std::string& provider) const
87 {
88 if(provider == "base" || provider.empty())
89 {
90 return std::unique_ptr<PK_Ops::Verification>(
91 new XMSS_Verification_Operation(*this));
92 }
93 throw Provider_Not_Found(algo_name(), provider);
94 }
95
96 std::vector<uint8_t> XMSS_PublicKey::raw_public_key() const
97 {
98 std::vector<uint8_t> result
99 {
100 static_cast<uint8_t>(m_xmss_params.oid() >> 24),
101 static_cast<uint8_t>(m_xmss_params.oid() >> 16),
102 static_cast<uint8_t>(m_xmss_params.oid() >> 8),
103 static_cast<uint8_t>(m_xmss_params.oid())
104 };
105
106 std::copy(m_root.begin(), m_root.end(), std::back_inserter(result));
107 std::copy(m_public_seed.begin(),
108 m_public_seed.end(),
109 std::back_inserter(result));
110
111 return result;
112 }
113
114 }
Botan::XMSS_PublicKey::create_verification_op
std::unique_ptr< PK_Ops::Verification > create_verification_op(const std::string &, const std::string &provider) const override
Definition: xmss_publickey.cpp:85
Botan::XMSS_PublicKey::m_public_seed
secure_vector< uint8_t > m_public_seed
Definition: xmss_publickey.h:254
Botan::XMSS_Verification_Operation
Definition: xmss_verification_operation.h:27
Botan::XMSS_Parameters::element_size
size_t element_size() const
Definition: xmss_parameters.h:67
Botan::XMSS_PublicKey::m_root
secure_vector< uint8_t > m_root
Definition: xmss_publickey.h:253
Botan::XMSS_PublicKey
Definition: xmss_publickey.h:39
Botan::Decoding_Error
Definition: exceptn.h:199
Botan::XMSS_Parameters::oid
xmss_algorithm_t oid() const
Definition: xmss_parameters.h:84
Botan::XMSS_PublicKey::raw_public_key
virtual std::vector< uint8_t > raw_public_key() const
Definition: xmss_publickey.cpp:96
Botan::XMSS_PublicKey::size
virtual size_t size() const
Definition: xmss_publickey.h:235
Botan
Definition: alg_id.cpp:13
Botan::OCTET_STRING
Definition: asn1_obj.h:36
Botan::XMSS_PublicKey::algo_name
std::string algo_name() const override
Definition: xmss_publickey.h:187
Botan::XMSS_PublicKey::XMSS_PublicKey
XMSS_PublicKey(XMSS_Parameters::xmss_algorithm_t xmss_oid, RandomNumberGenerator &rng)
Definition: xmss_publickey.h:51
Botan::XMSS_Parameters::xmss_algorithm_t
xmss_algorithm_t
Definition: xmss_parameters.h:26
Botan::XMSS_PublicKey::m_xmss_params
XMSS_Parameters m_xmss_params
Definition: xmss_publickey.h:251
Botan::Provider_Not_Found
Definition: exceptn.h:278
Botan::XMSS_PublicKey::m_raw_key
std::vector< uint8_t > m_raw_key
Definition: xmss_publickey.h:250