add get_asn1_flag to EcGroupRef

openssl-sys/src/handwritten/ec.rs

@@ -46,6 +46,8 @@ extern "C" {
 
     pub fn EC_GROUP_set_asn1_flag(key: *mut EC_GROUP, flag: c_int);
 
+    pub fn EC_GROUP_get_asn1_flag(group: *const EC_GROUP) -> c_int;
+
     pub fn EC_GROUP_get_curve_GFp(
         group: *const EC_GROUP,
         p: *mut BIGNUM,

openssl/src/ec.rs

@@ -294,6 +294,12 @@ impl EcGroupRef {
         }
     }
 
+    /// Gets the flag determining if the group corresponds to a named curve.
+    #[corresponds(EC_GROUP_get_asn1_flag)]
+    pub fn asn1_flag(&mut self) -> Asn1Flag {
+        unsafe { Asn1Flag(ffi::EC_GROUP_get_asn1_flag(self.as_ptr())) }
+    }
+
     /// Returns the name of the curve, if a name is associated.
     #[corresponds(EC_GROUP_get_curve_name)]
     pub fn curve_name(&self) -> Option<Nid> {
@@ -1265,4 +1271,12 @@ mod test {
         let group2 = EcGroup::from_curve_name(Nid::X9_62_PRIME239V3).unwrap();
         assert!(!g.is_on_curve(&group2, &mut ctx).unwrap());
     }
+
+    #[test]
+    #[cfg(not(any(ossl102, ossl101)))]
+    fn asn1_flag() {
+        let mut group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
+        let flag = group.asn1_flag();
+        assert_eq!(flag.0, Asn1Flag::NAMED_CURVE.0);
+    }
 }