Botan 3.3.0
Crypto and TLS for C&
emsa.cpp
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1/*
2* (C) 2015 Jack Lloyd
3*
4* Botan is released under the Simplified BSD License (see license.txt)
5*/
6
7#include <botan/internal/emsa.h>
8
9#include <botan/exceptn.h>
10#include <botan/hash.h>
11#include <botan/internal/scan_name.h>
12
13#if defined(BOTAN_HAS_EMSA_X931)
14 #include <botan/internal/emsa_x931.h>
15#endif
16
17#if defined(BOTAN_HAS_EMSA_PKCS1)
18 #include <botan/internal/emsa_pkcs1.h>
19#endif
20
21#if defined(BOTAN_HAS_EMSA_PSSR)
22 #include <botan/internal/pssr.h>
23#endif
24
25#if defined(BOTAN_HAS_EMSA_RAW)
26 #include <botan/internal/emsa_raw.h>
27#endif
28
29#if defined(BOTAN_HAS_ISO_9796)
30 #include <botan/internal/iso9796.h>
31#endif
32
33namespace Botan {
34
35std::unique_ptr<EMSA> EMSA::create(std::string_view algo_spec) {
36 SCAN_Name req(algo_spec);
37
38#if defined(BOTAN_HAS_EMSA_PKCS1)
39 if(req.algo_name() == "EMSA_PKCS1" || req.algo_name() == "PKCS1v15" || req.algo_name() == "EMSA-PKCS1-v1_5" ||
40 req.algo_name() == "EMSA3") {
41 if(req.arg_count() == 2 && req.arg(0) == "Raw") {
42 return std::make_unique<EMSA_PKCS1v15_Raw>(req.arg(1));
43 } else if(req.arg_count() == 1) {
44 if(req.arg(0) == "Raw") {
45 return std::make_unique<EMSA_PKCS1v15_Raw>();
46 } else {
47 if(auto hash = HashFunction::create(req.arg(0))) {
48 return std::make_unique<EMSA_PKCS1v15>(std::move(hash));
49 }
50 }
51 }
52 }
53#endif
54
55#if defined(BOTAN_HAS_EMSA_PSSR)
56 if(req.algo_name() == "PSS_Raw" || req.algo_name() == "PSSR_Raw") {
57 if(req.arg_count_between(1, 3) && req.arg(1, "MGF1") == "MGF1") {
58 if(auto hash = HashFunction::create(req.arg(0))) {
59 if(req.arg_count() == 3) {
60 const size_t salt_size = req.arg_as_integer(2, 0);
61 return std::make_unique<PSSR_Raw>(std::move(hash), salt_size);
62 } else {
63 return std::make_unique<PSSR_Raw>(std::move(hash));
64 }
65 }
66 }
67 }
68
69 if(req.algo_name() == "PSS" || req.algo_name() == "PSSR" || req.algo_name() == "EMSA-PSS" ||
70 req.algo_name() == "PSS-MGF1" || req.algo_name() == "EMSA4") {
71 if(req.arg_count_between(1, 3) && req.arg(1, "MGF1") == "MGF1") {
72 if(auto hash = HashFunction::create(req.arg(0))) {
73 if(req.arg_count() == 3) {
74 const size_t salt_size = req.arg_as_integer(2, 0);
75 return std::make_unique<PSSR>(std::move(hash), salt_size);
76 } else {
77 return std::make_unique<PSSR>(std::move(hash));
78 }
79 }
80 }
81 }
82#endif
83
84#if defined(BOTAN_HAS_ISO_9796)
85 if(req.algo_name() == "ISO_9796_DS2") {
86 if(req.arg_count_between(1, 3)) {
87 if(auto hash = HashFunction::create(req.arg(0))) {
88 const size_t salt_size = req.arg_as_integer(2, hash->output_length());
89 const bool implicit = req.arg(1, "exp") == "imp";
90 return std::make_unique<ISO_9796_DS2>(std::move(hash), implicit, salt_size);
91 }
92 }
93 }
94 //ISO-9796-2 DS 3 is deterministic and DS2 without a salt
95 if(req.algo_name() == "ISO_9796_DS3") {
96 if(req.arg_count_between(1, 2)) {
97 if(auto hash = HashFunction::create(req.arg(0))) {
98 const bool implicit = req.arg(1, "exp") == "imp";
99 return std::make_unique<ISO_9796_DS3>(std::move(hash), implicit);
100 }
101 }
102 }
103#endif
104
105#if defined(BOTAN_HAS_EMSA_X931)
106 if(req.algo_name() == "EMSA_X931" || req.algo_name() == "EMSA2" || req.algo_name() == "X9.31") {
107 if(req.arg_count() == 1) {
108 if(auto hash = HashFunction::create(req.arg(0))) {
109 return std::make_unique<EMSA_X931>(std::move(hash));
110 }
111 }
112 }
113#endif
114
115#if defined(BOTAN_HAS_EMSA_RAW)
116 if(req.algo_name() == "Raw") {
117 if(req.arg_count() == 0) {
118 return std::make_unique<EMSA_Raw>();
119 } else {
120 auto hash = HashFunction::create(req.arg(0));
121 if(hash) {
122 return std::make_unique<EMSA_Raw>(hash->output_length());
123 }
124 }
125 }
126#endif
127
128 return nullptr;
129}
130
131std::unique_ptr<EMSA> EMSA::create_or_throw(std::string_view algo_spec) {
132 auto emsa = EMSA::create(algo_spec);
133 if(emsa) {
134 return emsa;
135 }
136 throw Algorithm_Not_Found(algo_spec);
137}
138
139} // namespace Botan
static std::unique_ptr< EMSA > create_or_throw(std::string_view algo_spec)
Definition emsa.cpp:131
static std::unique_ptr< EMSA > create(std::string_view algo_spec)
Definition emsa.cpp:35
static std::unique_ptr< HashFunction > create(std::string_view algo_spec, std::string_view provider="")
Definition hash.cpp:107
std::string arg(size_t i) const
size_t arg_count() const
Definition scan_name.h:49
const std::string & algo_name() const
Definition scan_name.h:44
size_t arg_as_integer(size_t i, size_t def_value) const
bool arg_count_between(size_t lower, size_t upper) const
Definition scan_name.h:56