Add PKey::bits

openssl-sys/src/ossl10x.rs

@@ -600,6 +600,7 @@ extern {
                            line: c_int) -> c_int;
     pub fn EVP_MD_CTX_create() -> *mut EVP_MD_CTX;
     pub fn EVP_MD_CTX_destroy(ctx: *mut EVP_MD_CTX);
+    pub fn EVP_PKEY_bits(key: *mut EVP_PKEY) -> c_int;
 
     pub fn sk_num(st: *const _STACK) -> c_int;
     pub fn sk_value(st: *const _STACK, n: c_int) -> *mut c_void;

openssl-sys/src/ossl110.rs

@@ -147,6 +147,7 @@ extern {
     pub fn X509_STORE_CTX_get0_chain(ctx: *mut ::X509_STORE_CTX) -> *mut stack_st_X509;
     pub fn EVP_MD_CTX_new() -> *mut EVP_MD_CTX;
     pub fn EVP_MD_CTX_free(ctx: *mut EVP_MD_CTX);
+    pub fn EVP_PKEY_bits(key: *const EVP_PKEY) -> c_int;
 
     pub fn OpenSSL_version_num() -> c_ulong;
     pub fn OpenSSL_version(key: c_int) -> *const c_char;

openssl/src/pkey.rs

@@ -92,6 +92,15 @@ impl PKeyRef {
         Ok(mem_bio.get_buf().to_owned())
     }
 
+    /// Returns the size of the key.
+    ///
+    /// This corresponds to the bit length of the modulus of an RSA key, and the bit length of the
+    /// group order for an elliptic curve key, for example.
+    pub fn bits(&self) -> usize {
+        unsafe { ffi::EVP_PKEY_bits(self.as_ptr()) as usize }
+    }
+
+    /// Compares the public component of this key with another.
     pub fn public_eq(&self, other: &PKeyRef) -> bool {
         unsafe { ffi::EVP_PKEY_cmp(self.as_ptr(), other.as_ptr()) == 1 }
     }