crypto: implement RSA-2048-PSS

libraries/libvapours/include/vapours/crypto/crypto_rsa_pss_verifier.hpp

@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <vapours/common.hpp>
+#include <vapours/assert.hpp>
+#include <vapours/util.hpp>
+#include <vapours/crypto/crypto_rsa_calculator.hpp>
+#include <vapours/crypto/impl/crypto_rsa_pss_impl.hpp>
+
+namespace ams::crypto {
+
+    template<size_t ModulusSize, typename Hash> /* requires HashFunction<Hash> */
+    class RsaPssVerifier {
+        NON_COPYABLE(RsaPssVerifier);
+        NON_MOVEABLE(RsaPssVerifier);
+        public:
+            static constexpr size_t HashSize               = Hash::HashSize;
+            static constexpr size_t SaltSize               = Hash::HashSize;
+            static constexpr size_t SignatureSize          = ModulusSize;
+            static constexpr size_t MaximumExponentSize    = 3;
+            static constexpr size_t RequiredWorkBufferSize = RsaCalculator<ModulusSize, MaximumExponentSize>::RequiredWorkBufferSize;
+        private:
+            enum class State {
+                None,
+                Initialized,
+                Done,
+            };
+        private:
+            RsaCalculator<ModulusSize, MaximumExponentSize> calculator;
+            Hash hash;
+            State state;
+        public:
+            RsaPssVerifier() : state(State::None) { /* ... */ }
+            ~RsaPssVerifier() { }
+
+            bool Initialize(const void *mod, size_t mod_size, const void *exp, size_t exp_size) {
+                this->hash.Initialize();
+                if (this->calculator.Initialize(mod, mod_size, exp, exp_size)) {
+                    this->state = State::Initialized;
+                    return true;
+                } else {
+                    return false;
+                }
+            }
+
+            void Update(const void *data, size_t size) {
+                return this->hash.Update(data, size);
+            }
+
+            bool Verify(const void *signature, size_t size) {
+                AMS_ASSERT(this->state == State::Initialized);
+                AMS_ASSERT(size == SignatureSize);
+                ON_SCOPE_EXIT { this->state = State::Done; };
+
+                impl::RsaPssImpl<Hash> impl;
+                u8 message[SignatureSize];
+                ON_SCOPE_EXIT { ClearMemory(message, sizeof(message)); };
+
+                return this->calculator.ExpMod(message, signature, SignatureSize) &&
+                       impl.Verify(message, sizeof(message), std::addressof(this->hash));
+            }
+
+            bool Verify(const void *signature, size_t size, void *work_buf, size_t work_buf_size) {
+                AMS_ASSERT(this->state == State::Initialized);
+                AMS_ASSERT(size == SignatureSize);
+                ON_SCOPE_EXIT { this->state = State::Done; };
+
+                impl::RsaPssImpl<Hash> impl;
+                u8 message[SignatureSize];
+                ON_SCOPE_EXIT { ClearMemory(message, sizeof(message)); };
+
+                return this->calculator.ExpMod(message, signature, SignatureSize, work_buf, work_buf_size) &&
+                       impl.Verify(message, sizeof(message), std::addressof(this->hash));
+            }
+
+            static bool Verify(const void *sig, size_t sig_size, const void *mod, size_t mod_size, const void *exp, size_t exp_size, const void *msg, size_t msg_size) {
+                RsaPssVerifier<ModulusSize, Hash> verifier;
+                if (!verifier.Initialize(mod, mod_size, exp, exp_size)) {
+                    return false;
+                }
+                verifier.Update(msg, msg_size);
+                return verifier.Verify(sig, sig_size);
+            }
+
+            static bool Verify(const void *sig, size_t sig_size, const void *mod, size_t mod_size, const void *exp, size_t exp_size, const void *msg, size_t msg_size, void *work_buf, size_t work_buf_size) {
+                RsaPssVerifier<ModulusSize, Hash> verifier;
+                if (!verifier.Initialize(mod, mod_size, exp, exp_size)) {
+                    return false;
+                }
+                verifier.Update(msg, msg_size);
+                return verifier.Verify(sig, sig_size, work_buf, work_buf_size);
+            }
+    };
+
+}