Add support for raw private/public keys (#646)

Add OpenSSL::PKey.new_raw_private_key, #raw_private_key and public
equivalents. These methods are useful for importing and exporting keys
that support "raw private/public key". Currently, OpenSSL implements
X25519/X448 and Ed25519/Ed448 keys.

[rhe: rewrote commit message]

Co-authored-by: Bart de Water <bartdewater@gmail.com>

1 files changed, 132 insertions, 0 deletions

diff --git a/ext/openssl/ossl_pkey.c b/ext/openssl/ossl_pkey.c
index 9caeb562..952a6851 100644
--- a/ext/openssl/ossl_pkey.c
+++ b/ext/openssl/ossl_pkey.c
@@ -628,6 +628,72 @@ ossl_pkey_initialize_copy(VALUE self, VALUE other)
 }
 #endif
 
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+/*
+ *  call-seq:
+ *      OpenSSL::PKey.new_raw_private_key(algo, string) -> PKey
+ *
+ * See the OpenSSL documentation for EVP_PKEY_new_raw_private_key()
+ */
+
+static VALUE
+ossl_pkey_new_raw_private_key(VALUE self, VALUE type, VALUE key)
+{
+    EVP_PKEY *pkey;
+    const EVP_PKEY_ASN1_METHOD *ameth;
+    int pkey_id;
+    size_t keylen;
+
+    StringValue(type);
+    StringValue(key);
+    ameth = EVP_PKEY_asn1_find_str(NULL, RSTRING_PTR(type), RSTRING_LENINT(type));
+    if (!ameth)
+        ossl_raise(ePKeyError, "algorithm %"PRIsVALUE" not found", type);
+    EVP_PKEY_asn1_get0_info(&pkey_id, NULL, NULL, NULL, NULL, ameth);
+
+    keylen = RSTRING_LEN(key);
+
+    pkey = EVP_PKEY_new_raw_private_key(pkey_id, NULL, (unsigned char *)RSTRING_PTR(key), keylen);
+    if (!pkey)
+        ossl_raise(ePKeyError, "EVP_PKEY_new_raw_private_key");
+
+    return ossl_pkey_new(pkey);
+}
+#endif
+
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+/*
+ *  call-seq:
+ *      OpenSSL::PKey.new_raw_public_key(algo, string) -> PKey
+ *
+ * See the OpenSSL documentation for EVP_PKEY_new_raw_public_key()
+ */
+
+static VALUE
+ossl_pkey_new_raw_public_key(VALUE self, VALUE type, VALUE key)
+{
+    EVP_PKEY *pkey;
+    const EVP_PKEY_ASN1_METHOD *ameth;
+    int pkey_id;
+    size_t keylen;
+
+    StringValue(type);
+    StringValue(key);
+    ameth = EVP_PKEY_asn1_find_str(NULL, RSTRING_PTR(type), RSTRING_LENINT(type));
+    if (!ameth)
+        ossl_raise(ePKeyError, "algorithm %"PRIsVALUE" not found", type);
+    EVP_PKEY_asn1_get0_info(&pkey_id, NULL, NULL, NULL, NULL, ameth);
+
+    keylen = RSTRING_LEN(key);
+
+    pkey = EVP_PKEY_new_raw_public_key(pkey_id, NULL, (unsigned char *)RSTRING_PTR(key), keylen);
+    if (!pkey)
+        ossl_raise(ePKeyError, "EVP_PKEY_new_raw_public_key");
+
+    return ossl_pkey_new(pkey);
+}
+#endif
+
 /*
  * call-seq:
  *    pkey.oid -> string
@@ -816,6 +882,35 @@ ossl_pkey_private_to_pem(int argc, VALUE *argv, VALUE self)
     return do_pkcs8_export(argc, argv, self, 0);
 }
 
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+/*
+ *  call-seq:
+ *     pkey.raw_private_key   => string
+ *
+ *  See the OpenSSL documentation for EVP_PKEY_get_raw_private_key()
+ */
+
+static VALUE
+ossl_pkey_raw_private_key(VALUE self)
+{
+    EVP_PKEY *pkey;
+    VALUE str;
+    size_t len;
+
+    GetPKey(self, pkey);
+    if (EVP_PKEY_get_raw_private_key(pkey, NULL, &len) != 1)
+        ossl_raise(ePKeyError, "EVP_PKEY_get_raw_private_key");
+    str = rb_str_new(NULL, len);
+
+    if (EVP_PKEY_get_raw_private_key(pkey, (unsigned char *)RSTRING_PTR(str), &len) != 1)
+        ossl_raise(ePKeyError, "EVP_PKEY_get_raw_private_key");
+
+    rb_str_set_len(str, len);
+
+    return str;
+}
+#endif
+
 VALUE
 ossl_pkey_export_spki(VALUE self, int to_der)
 {
@@ -865,6 +960,35 @@ ossl_pkey_public_to_pem(VALUE self)
     return ossl_pkey_export_spki(self, 0);
 }
 
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+/*
+ *  call-seq:
+ *     pkey.raw_public_key   => string
+ *
+ *  See the OpenSSL documentation for EVP_PKEY_get_raw_public_key()
+ */
+
+static VALUE
+ossl_pkey_raw_public_key(VALUE self)
+{
+    EVP_PKEY *pkey;
+    VALUE str;
+    size_t len;
+
+    GetPKey(self, pkey);
+    if (EVP_PKEY_get_raw_public_key(pkey, NULL, &len) != 1)
+        ossl_raise(ePKeyError, "EVP_PKEY_get_raw_public_key");
+    str = rb_str_new(NULL, len);
+
+    if (EVP_PKEY_get_raw_public_key(pkey, (unsigned char *)RSTRING_PTR(str), &len) != 1)
+        ossl_raise(ePKeyError, "EVP_PKEY_get_raw_public_key");
+
+    rb_str_set_len(str, len);
+
+    return str;
+}
+#endif
+
 /*
  *  call-seq:
  *      pkey.compare?(another_pkey) -> true | false
@@ -1602,6 +1726,10 @@ Init_ossl_pkey(void)
     rb_define_module_function(mPKey, "read", ossl_pkey_new_from_data, -1);
     rb_define_module_function(mPKey, "generate_parameters", ossl_pkey_s_generate_parameters, -1);
     rb_define_module_function(mPKey, "generate_key", ossl_pkey_s_generate_key, -1);
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+    rb_define_module_function(mPKey, "new_raw_private_key", ossl_pkey_new_raw_private_key, 2);
+    rb_define_module_function(mPKey, "new_raw_public_key", ossl_pkey_new_raw_public_key, 2);
+#endif
 
     rb_define_alloc_func(cPKey, ossl_pkey_alloc);
     rb_define_method(cPKey, "initialize", ossl_pkey_initialize, 0);
@@ -1617,6 +1745,10 @@ Init_ossl_pkey(void)
     rb_define_method(cPKey, "private_to_pem", ossl_pkey_private_to_pem, -1);
     rb_define_method(cPKey, "public_to_der", ossl_pkey_public_to_der, 0);
     rb_define_method(cPKey, "public_to_pem", ossl_pkey_public_to_pem, 0);
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+    rb_define_method(cPKey, "raw_private_key", ossl_pkey_raw_private_key, 0);
+    rb_define_method(cPKey, "raw_public_key", ossl_pkey_raw_public_key, 0);
+#endif
     rb_define_method(cPKey, "compare?", ossl_pkey_compare, 1);
 
     rb_define_method(cPKey, "sign", ossl_pkey_sign, -1);