add Secret::set for c api

3 files changed, 37 insertions, 0 deletions

diff --git a/include/bls.hpp b/include/bls.hpp
index 955702a..cf251d5 100644
--- a/include/bls.hpp
+++ b/include/bls.hpp
@@ -88,6 +88,8 @@ class SecretKey {
 	friend void LagrangeInterpolation(G& r, const T& vec, const IdVec& idVec);
 	template<class T, class G>
 	friend struct Wrap;
+	template<class T, class G>
+	friend struct WrapPointer;
 public:
 	SecretKey();
 	~SecretKey();
@@ -129,6 +131,13 @@ public:
 		add secret key
 	*/
 	void add(const SecretKey& rhs);
+
+	// the following methods are for C api
+	/*
+		the size of msk must be k
+	*/
+	void set(const SecretKey *const *msk, size_t k, const Id& id);
+	void recover(const SecretKey *const *secVec, const Id *const *idVec, size_t n);
 };
 
 /*
@@ -142,6 +151,8 @@ class PublicKey {
 	friend void LagrangeInterpolation(G& r, const T& vec, const IdVec& idVec);
 	template<class T, class G>
 	friend struct Wrap;
+	template<class T, class G>
+	friend struct WrapPointer;
 public:
 	PublicKey();
 	~PublicKey();
diff --git a/src/bls.cpp b/src/bls.cpp
index 03f7d16..3dfab45 100644
--- a/src/bls.cpp
+++ b/src/bls.cpp
@@ -87,6 +87,18 @@ struct Wrap {
 	size_t size() const { return pv->size(); }
 };
 
+template<class T, class G>
+struct WrapPointer {
+	const T *const *v;
+	size_t k;
+	WrapPointer(const T *const *v, size_t k) : v(v), k(k) {}
+	const G& operator[](size_t i) const
+	{
+		return v[i]->self_->get();
+	}
+	size_t size() const { return k; }
+};
+
 struct Polynomial {
 	FrVec c; // f[x] = sum_{i=0}^{k-1} c[i] x^i
 	void init(const Fr& s, int k)
@@ -426,6 +438,11 @@ void SecretKey::set(const SecretKeyVec& msk, const Id& id)
 	Wrap<SecretKey, Fr> w(msk);
 	evalPoly(self_->s, id.self_->v, w);
 }
+void SecretKey::set(const SecretKey *const *msk, size_t k, const Id& id)
+{
+	WrapPointer<SecretKey, Fr> w(msk, k);
+	evalPoly(self_->s, id.self_->v, w);
+}
 
 void SecretKey::recover(const SecretKeyVec& secVec, const IdVec& idVec)
 {
diff --git a/test/bls_test.cpp b/test/bls_test.cpp
index e9ff953..47ba330 100644
--- a/test/bls_test.cpp
+++ b/test/bls_test.cpp
@@ -72,12 +72,21 @@ CYBOZU_TEST_AUTO(k_of_n)
 	bls::SecretKeyVec msk;
 	sec0.getMasterSecretKey(msk, k);
 
+	std::vector<const bls::SecretKey*> pmsk(k);
+	for (size_t i = 0; i < k; i++) {
+		pmsk[i] = &msk[i];
+	}
+
 	bls::SecretKeyVec allPrvVec(n);
 	bls::IdVec allIdVec(n);
 	for (int i = 0; i < n; i++) {
 		int id = i + 1;
 		allPrvVec[i].set(msk, id);
 		allIdVec[i] = id;
+
+		bls::SecretKey p;
+		p.set(&pmsk[0], k, id);
+		CYBOZU_TEST_EQUAL(allPrvVec[i], p);
 	}
 
 	bls::SignVec allSignVec(n);