pki: Use consistent API for ssh_pki_export_privkey_to_pubkey().

include/libssh/libssh.h

@@ -449,6 +449,9 @@ LIBSSH_API int ssh_pki_import_pubkey_base64(const char *b64_key,
                                             ssh_key *pkey);
 LIBSSH_API int ssh_pki_import_pubkey_file(const char *filename,
                                           ssh_key *pkey);
+
+LIBSSH_API int ssh_pki_export_privkey_to_pubkey(const ssh_key privkey,
+                                                ssh_key *pkey);
 LIBSSH_API int ssh_pki_export_pubkey_base64(const ssh_key key,
                                             char **b64_key);
 LIBSSH_API int ssh_pki_export_pubkey_file(const ssh_key key,

include/libssh/pki.h

@@ -80,9 +80,6 @@ int ssh_pki_export_pubkey_blob(const ssh_key key,
 int ssh_pki_import_pubkey_blob(const ssh_string key_blob,
                                ssh_key *pkey);
 
-/* SSH Private Key Functions */
-ssh_key ssh_pki_publickey_from_privatekey(const ssh_key privkey);
-
 /* SSH Signing Functions */
 ssh_string ssh_pki_do_sign(ssh_session session, ssh_buffer sigbuf,
     ssh_key privatekey);

src/auth.c

@@ -1118,8 +1118,8 @@ int ssh_userauth_publickey_auto(ssh_session session,
                 continue;
             }
 
-            pubkey = ssh_pki_publickey_from_privatekey(privkey);
+            rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-            if (pubkey == NULL) {
+            if (rc == SSH_ERROR) {
                 ssh_key_free(privkey);
                 return SSH_AUTH_ERROR;
             }

src/pki.c

@@ -784,19 +784,33 @@ int ssh_pki_import_pubkey_file(const char *filename, ssh_key *pkey)
 }
 
 /**
- * @brief Generate and duplicate a public key from a private key.
+ * @brief Create a public key from a private key.
  *
- * @param[in] privkey   The private key to get the public key from.
+ * @param[in]  privkey  The private key to get the public key from.
+ *
+ * @param[out] pkey     A pointer to store the newly allocated public key. You
+ *                      NEED to free the key.
  *
  * @return              A public key, NULL on error.
+ *
+ * @see ssh_key_free()
  */
-ssh_key ssh_pki_publickey_from_privatekey(const ssh_key privkey) {
+int ssh_pki_export_privkey_to_pubkey(const ssh_key privkey,
+                                     ssh_key *pkey)
+{
+    ssh_key pubkey;
 
     if (privkey == NULL || !ssh_key_is_private(privkey)) {
-        return NULL;
+        return SSH_ERROR;
     }
 
-    return pki_key_dup(privkey, 1);
+    pubkey = pki_key_dup(privkey, 1);
+    if (pubkey == NULL) {
+        return SSH_ERROR;
+    }
+
+    *pkey = pubkey;
+    return SSH_OK;
 }
 
 /**

src/server.c

@@ -189,8 +189,8 @@ static int dh_handshake_server(ssh_session session) {
       privkey = NULL;
   }
 
-  pubkey = ssh_pki_publickey_from_privatekey(privkey);
+  rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-  if (pubkey == NULL) {
+  if (rc < 0) {
     ssh_set_error(session, SSH_FATAL,
         "Could not get the public key from the private key");
     ssh_string_free(f);

tests/unittests/torture_pki.c

@@ -292,8 +292,8 @@ static void torture_pki_pki_publickey_from_privatekey_RSA(void **state) {
     rc = ssh_pki_import_privkey_base64(key_str, passphrase, NULL, NULL, &key);
     assert_true(rc == 0);
 
-    pubkey = ssh_pki_publickey_from_privatekey(key);
+    rc = ssh_pki_export_privkey_to_pubkey(key, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     free(key_str);
     ssh_key_free(key);
@@ -315,8 +315,8 @@ static void torture_pki_pki_publickey_from_privatekey_DSA(void **state) {
     rc = ssh_pki_import_privkey_base64(key_str, passphrase, NULL, NULL, &key);
     assert_true(rc == 0);
 
-    pubkey = ssh_pki_publickey_from_privatekey(key);
+    rc = ssh_pki_export_privkey_to_pubkey(key, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     free(key_str);
     ssh_key_free(key);
@@ -422,8 +422,8 @@ static void torture_generate_pubkey_from_privkey_rsa(void **state) {
                                      &privkey);
     assert_true(rc == 0);
 
-    pubkey = ssh_pki_publickey_from_privatekey(privkey);
+    rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     rc = ssh_pki_export_pubkey_file(pubkey, LIBSSH_RSA_TESTKEY ".pub");
     assert_true(rc == 0);
@@ -463,8 +463,8 @@ static void torture_generate_pubkey_from_privkey_dsa(void **state) {
                                      &privkey);
     assert_true(rc == 0);
 
-    pubkey = ssh_pki_publickey_from_privatekey(privkey);
+    rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     rc = ssh_pki_export_pubkey_file(pubkey, LIBSSH_DSA_TESTKEY ".pub");
     assert_true(rc == 0);
@@ -508,8 +508,8 @@ static void torture_pki_duplicate_key_rsa(void **state)
     privkey_dup = ssh_key_dup(privkey);
     assert_true(privkey_dup != NULL);
 
-    pubkey = ssh_pki_publickey_from_privatekey(privkey_dup);
+    rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     rc = ssh_pki_export_pubkey_base64(pubkey, &b64_key_gen);
     assert_true(rc == 0);
@@ -551,8 +551,8 @@ static void torture_pki_duplicate_key_dsa(void **state)
     privkey_dup = ssh_key_dup(privkey);
     assert_true(privkey_dup != NULL);
 
-    pubkey = ssh_pki_publickey_from_privatekey(privkey_dup);
+    rc = ssh_pki_export_privkey_to_pubkey(privkey, &pubkey);
-    assert_true(pubkey != NULL);
+    assert_true(rc == SSH_OK);
 
     rc = ssh_pki_export_pubkey_base64(pubkey, &b64_key_gen);
     assert_true(rc == 0);
@@ -589,7 +589,7 @@ int torture_run_tests(void) {
         unit_test_setup_teardown(torture_pki_import_privkey_base64_passphrase,
                                  setup_both_keys_passphrase,
                                  teardown),
-        /* ssh_pki_publickey_from_privatekey */
+        /* ssh_pki_export_privkey_to_pubkey */
         unit_test_setup_teardown(torture_pki_pki_publickey_from_privatekey_RSA,
                                  setup_rsa_key,
                                  teardown),