DH: Add export of keys and domain parameters from provider

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10169)

diff --git a/providers/implementations/keymgmt/dh_kmgmt.c b/providers/implementations/keymgmt/dh_kmgmt.c
index cb9502fc22eb2aaca3e58cc4b002a8eddbf8e7be..4120155619e180083d1d1394c1a5c9f8020e64e4 100644 (file)
--- a/providers/implementations/keymgmt/dh_kmgmt.c
+++ b/providers/implementations/keymgmt/dh_kmgmt.c
@@ -15,7 +15,9 @@
 #include "prov/implementations.h"
 
 static OSSL_OP_keymgmt_importdomparams_fn dh_importdomparams;
+static OSSL_OP_keymgmt_exportdomparams_fn dh_exportdomparams;
 static OSSL_OP_keymgmt_importkey_fn dh_importkey;
+static OSSL_OP_keymgmt_exportkey_fn dh_exportkey;
 
 static int params_to_domparams(DH *dh, const OSSL_PARAM params[])
 {
@@ -43,6 +45,25 @@ static int params_to_domparams(DH *dh, const OSSL_PARAM params[])
     return 0;
 }
 
+static int domparams_to_params(DH *dh, OSSL_PARAM params[])
+{
+    OSSL_PARAM *p;
+    const BIGNUM *dh_p = NULL, *dh_g = NULL;
+
+    if (dh == NULL)
+        return 0;
+
+    DH_get0_pqg(dh, &dh_p, NULL, &dh_g);
+    if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_FFC_P)) != NULL
+        && !OSSL_PARAM_set_BN(p, dh_p))
+        return 0;
+    if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_FFC_G)) != NULL
+        && !OSSL_PARAM_set_BN(p, dh_g))
+        return 0;
+
+    return 1;
+}
+
 static int params_to_key(DH *dh, const OSSL_PARAM params[])
 {
     const OSSL_PARAM *param_priv_key, *param_pub_key;
@@ -84,6 +105,29 @@ static int params_to_key(DH *dh, const OSSL_PARAM params[])
     return 0;
 }
 
+static int key_to_params(DH *dh, OSSL_PARAM params[])
+{
+    OSSL_PARAM *p;
+    const BIGNUM *priv_key = NULL, *pub_key = NULL;
+
+    if (dh == NULL)
+        return 0;
+    if (!domparams_to_params(dh, params))
+        return 0;
+
+    DH_get0_key(dh, &pub_key, &priv_key);
+    if ((p = OSSL_PARAM_locate(params,
+                                     OSSL_PKEY_PARAM_DH_PRIV_KEY)) != NULL
+        && !OSSL_PARAM_set_BN(p, priv_key))
+        return 0;
+    if ((p = OSSL_PARAM_locate(params,
+                                     OSSL_PKEY_PARAM_DH_PUB_KEY)) != NULL
+        && !OSSL_PARAM_set_BN(p, pub_key))
+        return 0;
+
+    return 1;
+}
+
 static void *dh_importdomparams(void *provctx, const OSSL_PARAM params[])
 {
     DH *dh;
@@ -96,6 +140,13 @@ static void *dh_importdomparams(void *provctx, const OSSL_PARAM params[])
     return dh;
 }
 
+static int dh_exportdomparams(void *domparams, OSSL_PARAM params[])
+{
+    DH *dh = domparams;
+
+    return dh != NULL && !domparams_to_params(dh, params);
+}
+
 static void *dh_importkey(void *provctx, const OSSL_PARAM params[])
 {
     DH *dh;
@@ -108,14 +159,23 @@ static void *dh_importkey(void *provctx, const OSSL_PARAM params[])
     return dh;
 }
 
+static int dh_exportkey(void *key, OSSL_PARAM params[])
+{
+    DH *dh = key;
+
+    return dh != NULL && !key_to_params(dh, params);
+}
+
 const OSSL_DISPATCH dh_keymgmt_functions[] = {
     /*
      * TODO(3.0) When implementing OSSL_FUNC_KEYMGMT_GENKEY, remember to also
      * implement OSSL_FUNC_KEYMGMT_EXPORTKEY.
      */
     { OSSL_FUNC_KEYMGMT_IMPORTDOMPARAMS, (void (*)(void))dh_importdomparams },
+    { OSSL_FUNC_KEYMGMT_EXPORTDOMPARAMS, (void (*)(void))dh_exportdomparams },
     { OSSL_FUNC_KEYMGMT_FREEDOMPARAMS, (void (*)(void))DH_free },
     { OSSL_FUNC_KEYMGMT_IMPORTKEY, (void (*)(void))dh_importkey },
+    { OSSL_FUNC_KEYMGMT_EXPORTKEY, (void (*)(void))dh_exportkey },
     { OSSL_FUNC_KEYMGMT_FREEKEY, (void (*)(void))DH_free },
     { 0, NULL }
 };