diffie-hellman: Use bool instead of status_t as get_shared_secret() return value

While such a change is not unproblematic, keeping status_t makes the API
inconsistent once we introduce return values for the public value operations.

src/libstrongswan/plugins/gcrypt/gcrypt_dh.c

@@ -138,15 +138,15 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 	*value = export_mpi(this->ya, this->p_len);
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_gcrypt_dh_t *this, chunk_t *secret)
 {
 	if (!this->zz)
 	{
-		return FAILED;
+		return FALSE;
 	}
 	*secret = export_mpi(this->zz, this->p_len);
-	return SUCCESS;
+	return TRUE;
 }
 
 METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t,

src/libstrongswan/plugins/gmp/gmp_diffie_hellman.c

@@ -155,20 +155,20 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 	}
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_gmp_diffie_hellman_t *this, chunk_t *secret)
 {
 	if (!this->computed)
 	{
-		return FAILED;
+		return FALSE;
 	}
 	secret->len = this->p_len;
 	secret->ptr = mpz_export(NULL, NULL, 1, secret->len, 1, 0, this->zz);
 	if (secret->ptr == NULL)
 	{
-		return FAILED;
+		return FALSE;
 	}
-	return SUCCESS;
+	return TRUE;
 }
 
 METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t,

src/libstrongswan/plugins/ntru/ntru_ke.c

@@ -139,17 +139,17 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 	}
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_ntru_ke_t *this, chunk_t *secret)
 {
 	if (!this->computed || !this->shared_secret.len)
 	{
 		*secret = chunk_empty;
-		return FAILED;
+		return FALSE;
 	}
 	*secret = chunk_clone(this->shared_secret);
 
-	return SUCCESS;
+	return TRUE;
 }
 
 

src/libstrongswan/plugins/openssl/openssl_diffie_hellman.c

@@ -70,19 +70,19 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 			  value->ptr + value->len - BN_num_bytes(this->dh->pub_key));
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_openssl_diffie_hellman_t *this, chunk_t *secret)
 {
 	if (!this->computed)
 	{
-		return FAILED;
+		return FALSE;
 	}
 	/* shared secret should requires a len according the DH group */
 	*secret = chunk_alloc(DH_size(this->dh));
 	memset(secret->ptr, 0, secret->len);
 	memcpy(secret->ptr + secret->len - this->shared_secret.len,
 		   this->shared_secret.ptr, this->shared_secret.len);
-	return SUCCESS;
+	return TRUE;
 }
 
 

src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c

@@ -241,15 +241,15 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 	ecp2chunk(this->ec_group, EC_KEY_get0_public_key(this->key), value, FALSE);
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_openssl_ec_diffie_hellman_t *this, chunk_t *secret)
 {
 	if (!this->computed)
 	{
-		return FAILED;
+		return FALSE;
 	}
 	*secret = chunk_clone(this->shared_secret);
-	return SUCCESS;
+	return TRUE;
 }
 
 METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t,

src/libstrongswan/plugins/pkcs11/pkcs11_dh.c

@@ -154,15 +154,15 @@ METHOD(diffie_hellman_t, get_my_public_value, void,
 	*value = chunk_clone(this->pub_key);
 }
 
-METHOD(diffie_hellman_t, get_shared_secret, status_t,
+METHOD(diffie_hellman_t, get_shared_secret, bool,
 	private_pkcs11_dh_t *this, chunk_t *secret)
 {
 	if (!this->secret.ptr)
 	{
-		return FAILED;
+		return FALSE;
 	}
 	*secret = chunk_clone(this->secret);
-	return SUCCESS;
+	return TRUE;
 }
 
 METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t,