1 files changed, 83 insertions, 0 deletions
diff --git a/src/engine/openssl/ossl_if.cpp b/src/engine/openssl/ossl_if.cpp
new file mode 100644
index 000000000..08a43e63e
--- /dev/null
+++ b/src/engine/openssl/ossl_if.cpp
@@ -0,0 +1,83 @@
+/*************************************************
+* OpenSSL IF Engine Source File                  *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/eng_ossl.h>
+#include <botan/bn_wrap.h>
+#include <openssl/opensslv.h>
+
+#if OPENSSL_VERSION_NUMBER < 0x0090700F
+  #error Your OpenSSL install is too old, upgrade to 0.9.7 or later
+#endif
+
+namespace Botan {
+
+#if defined(BOTAN_HAS_IF_PUBLIC_KEY_FAMILY)
+
+namespace {
+
+/*************************************************
+* OpenSSL IF Operation                           *
+*************************************************/
+class OpenSSL_IF_Op : public IF_Operation
+   {
+   public:
+      BigInt public_op(const BigInt&) const;
+      BigInt private_op(const BigInt&) const;
+
+      IF_Operation* clone() const { return new OpenSSL_IF_Op(*this); }
+
+      OpenSSL_IF_Op(const BigInt& e_bn, const BigInt& n_bn, const BigInt&,
+                const BigInt& p_bn, const BigInt& q_bn, const BigInt& d1_bn,
+                const BigInt& d2_bn, const BigInt& c_bn) :
+         e(e_bn), n(n_bn), p(p_bn), q(q_bn), d1(d1_bn), d2(d2_bn), c(c_bn) {}
+   private:
+      const OSSL_BN e, n, p, q, d1, d2, c;
+      OSSL_BN_CTX ctx;
+   };
+
+/*************************************************
+* OpenSSL IF Public Operation                    *
+*************************************************/
+BigInt OpenSSL_IF_Op::public_op(const BigInt& i_bn) const
+   {
+   OSSL_BN i(i_bn), r;
+   BN_mod_exp(r.value, i.value, e.value, n.value, ctx.value);
+   return r.to_bigint();
+   }
+
+/*************************************************
+* OpenSSL IF Private Operation                   *
+*************************************************/
+BigInt OpenSSL_IF_Op::private_op(const BigInt& i_bn) const
+   {
+   if(BN_is_zero(p.value))
+      throw Internal_Error("OpenSSL_IF_Op::private_op: No private key");
+
+   OSSL_BN j1, j2, h(i_bn);
+
+   BN_mod_exp(j1.value, h.value, d1.value, p.value, ctx.value);
+   BN_mod_exp(j2.value, h.value, d2.value, q.value, ctx.value);
+   BN_sub(h.value, j1.value, j2.value);
+   BN_mod_mul(h.value, h.value, c.value, p.value, ctx.value);
+   BN_mul(h.value, h.value, q.value, ctx.value);
+   BN_add(h.value, h.value, j2.value);
+   return h.to_bigint();
+   }
+
+}
+
+/*************************************************
+* Acquire an IF op                               *
+*************************************************/
+IF_Operation* OpenSSL_Engine::if_op(const BigInt& e, const BigInt& n,
+                                    const BigInt& d, const BigInt& p,
+                                    const BigInt& q, const BigInt& d1,
+                                    const BigInt& d2, const BigInt& c) const
+   {
+   return new OpenSSL_IF_Op(e, n, d, p, q, d1, d2, c);
+   }
+#endif
+
+}