diff --git a/NEWS b/NEWS
index ce72d610..7712c7d9 100644
--- a/NEWS
+++ b/NEWS
@@ -5,6 +5,9 @@ Noteworthy changes in version 1.21.0 (unreleased)
    gpgme_op_sign* to allow writing the output directly to a
    file.  [T6530]
 
+ * Extended gpgme_op_decrypt* and gpgme_op_verify* to allow
+   reading the input data directly from files.  [T6530]
+
  * qt: Allow writing the created archives directly to a
    file.  [T6530]
 
diff --git a/doc/gpgme.texi b/doc/gpgme.texi
index cf0525fc..fb604f30 100644
--- a/doc/gpgme.texi
+++ b/doc/gpgme.texi
@@ -5592,8 +5592,9 @@ An error code describing the reason why the key was found invalid.
 
 @deftypefun gpgme_error_t gpgme_op_decrypt (@w{gpgme_ctx_t @var{ctx}}, @w{gpgme_data_t @var{cipher}}, @w{gpgme_data_t @var{plain}})
 The function @code{gpgme_op_decrypt} decrypts the ciphertext in the
-data object @var{cipher} and stores it into the data object
-@var{plain}.
+data object @var{cipher} or, if a file name is set on the data object,
+the ciphertext stored in the corresponding file.  The decrypted
+ciphertext is stored into the data object @var{plain}.
 
 The function returns the error code @code{GPG_ERR_NO_ERROR} if the
 ciphertext could be decrypted successfully, @code{GPG_ERR_INV_VALUE}
@@ -5806,7 +5807,10 @@ detached signature, then the signed text should be provided in
 Otherwise, if @var{sig} is a normal (or cleartext) signature,
 @var{signed_text} should be a null pointer and @var{plain} should be a
 writable data object that will contain the plaintext after successful
-verification.
+verification.  If a file name is set on the data object @var{sig} (or
+on the data object @var{signed_text}), then the data of the signature
+(resp. the data of the signed text) is not read from the data object
+but from the file with the given file name.
 
 The results of the individual signature verifications can be retrieved
 with @code{gpgme_op_verify_result}.
diff --git a/src/engine-gpg.c b/src/engine-gpg.c
index ba45e55a..355d42fd 100644
--- a/src/engine-gpg.c
+++ b/src/engine-gpg.c
@@ -365,6 +365,18 @@ add_data (engine_gpg_t gpg, gpgme_data_t data, int dup_to, int inbound)
   return add_data_ext (gpg, data, dup_to, inbound, 0);
 }
 
+
+static gpgme_error_t
+add_file_name_arg_or_data (engine_gpg_t gpg, gpgme_data_t data, int dup_to, int inbound)
+{
+  const char *file_name = gpgme_data_get_file_name (data);
+  if (file_name)
+    return add_arg (gpg, file_name);
+  else
+    return add_data (gpg, data, dup_to, inbound);
+}
+
+
 /* Return true if the engine's version is at least VERSION.  */
 static int
 have_gpg_version (engine_gpg_t gpg, const char *version)
@@ -1883,7 +1895,7 @@ gpg_decrypt (void *engine,
       if (!err)
         err = add_arg (gpg, "--");
       if (!err)
-        err = add_data (gpg, ciph, 0, 0);
+        err = add_file_name_arg_or_data (gpg, ciph, 0, 0);
     }
   else
     {
@@ -1898,7 +1910,7 @@ gpg_decrypt (void *engine,
       if (!err)
         err = add_arg (gpg, "--");
       if (!err)
-        err = add_data (gpg, ciph, -1, 0);
+        err = add_file_name_arg_or_data (gpg, ciph, -1, 0);
     }
 
   if (!err)
@@ -3707,7 +3719,7 @@ gpg_verify (void *engine, gpgme_verify_flags_t flags, gpgme_data_t sig,
       if (!err)
         err = add_arg (gpg, "--");
       if (!err)
-        err = add_data (gpg, sig, 0, 0);
+        err = add_file_name_arg_or_data (gpg, sig, 0, 0);
     }
   else if (plaintext)
     {
@@ -3720,7 +3732,7 @@ gpg_verify (void *engine, gpgme_verify_flags_t flags, gpgme_data_t sig,
       if (!err)
 	err = add_arg (gpg, "--");
       if (!err)
-	err = add_data (gpg, sig, -1, 0);
+	err = add_file_name_arg_or_data (gpg, sig, -1, 0);
       if (!err)
 	err = add_data (gpg, plaintext, 1, 1);
     }
@@ -3732,9 +3744,9 @@ gpg_verify (void *engine, gpgme_verify_flags_t flags, gpgme_data_t sig,
       if (!err)
 	err = add_arg (gpg, "--");
       if (!err)
-	err = add_data (gpg, sig, -1, 0);
+	err = add_file_name_arg_or_data (gpg, sig, -1, 0);
       if (!err && signed_text)
-	err = add_data (gpg, signed_text, -1, 0);
+	err = add_file_name_arg_or_data (gpg, signed_text, -1, 0);
     }
 
   if (!err)
diff --git a/tests/run-decrypt.c b/tests/run-decrypt.c
index ee49ead6..de082d6f 100644
--- a/tests/run-decrypt.c
+++ b/tests/run-decrypt.c
@@ -94,6 +94,7 @@ show_usage (int ex)
          "  --archive        extract files from an encrypted archive\n"
          "  --directory DIR  extract the files into the directory DIR\n"
          "  --diagnostics    print diagnostics\n"
+         "  --direct-file-io pass FILE instead of stream with content of FILE to backend\n"
          , stderr);
   exit (ex);
 }
@@ -122,6 +123,7 @@ main (int argc, char **argv)
   int large_buffers = 0;
   int sensitive = 0;
   int diagnostics = 0;
+  int direct_file_io = 0;
 
   if (argc)
     { argc--; argv++; }
@@ -221,6 +223,11 @@ main (int argc, char **argv)
           directory = *argv;
           argc--; argv++;
         }
+      else if (!strcmp (*argv, "--direct-file-io"))
+        {
+          direct_file_io = 1;
+          argc--; argv++;
+        }
       else if (!strncmp (*argv, "--", 2))
         show_usage (1);
 
@@ -229,13 +236,16 @@ main (int argc, char **argv)
   if (argc < 1 || argc > 2)
     show_usage (1);
 
-  fp_in = fopen (argv[0], "rb");
-  if (!fp_in)
+  if (!direct_file_io)
     {
-      err = gpgme_error_from_syserror ();
-      fprintf (stderr, PGM ": can't open `%s': %s\n",
-               argv[0], gpgme_strerror (err));
-      exit (1);
+      fp_in = fopen (argv[0], "rb");
+      if (!fp_in)
+        {
+          err = gpgme_error_from_syserror ();
+          fprintf (stderr, PGM ": can't open `%s': %s\n",
+                   argv[0], gpgme_strerror (err));
+          exit (1);
+        }
     }
 
   init_gpgme (protocol);
@@ -303,13 +313,26 @@ main (int argc, char **argv)
         }
     }
 
-  err = gpgme_data_new_from_stream (&in, fp_in);
+  if (direct_file_io)
+    err = gpgme_data_new (&in);
+  else
+    err = gpgme_data_new_from_stream (&in, fp_in);
   if (err)
     {
       fprintf (stderr, PGM ": error allocating data object: %s\n",
                gpgme_strerror (err));
       exit (1);
     }
+  if (direct_file_io)
+    {
+      err = gpgme_data_set_file_name (in, argv[0]);
+      if (err)
+        {
+          fprintf (stderr, PGM ": error setting file name (in): %s\n",
+                   gpgme_strerror (err));
+          exit (1);
+        }
+    }
 
   err = gpgme_data_new (&out);
   if (err)
diff --git a/tests/run-verify.c b/tests/run-verify.c
index 8a400589..dba45557 100644
--- a/tests/run-verify.c
+++ b/tests/run-verify.c
@@ -239,6 +239,7 @@ show_usage (int ex)
          "  --archive        extract files from a signed archive FILE\n"
          "  --directory DIR  extract the files into the directory DIR\n"
          "  --diagnostics    print diagnostics\n"
+         "  --direct-file-io pass file names instead of streams with content of files to backend\n"
          , stderr);
   exit (ex);
 }
@@ -258,6 +259,7 @@ main (int argc, char **argv)
   int auto_key_import = 0;
   gpgme_data_encoding_t encoding = GPGME_DATA_ENCODING_NONE;
   int diagnostics = 0;
+  int direct_file_io = 0;
   int repeats = 1;
   int i;
 
@@ -343,6 +345,11 @@ main (int argc, char **argv)
           diagnostics = 1;
           argc--; argv++;
         }
+      else if (!strcmp (*argv, "--direct-file-io"))
+        {
+          direct_file_io = 1;
+          argc--; argv++;
+        }
       else if (!strncmp (*argv, "--", 2))
         show_usage (1);
 
@@ -369,24 +376,27 @@ main (int argc, char **argv)
           printf ("Repeat: %i\n", i);
         }
 
-      fp_sig = fopen (argv[0], "rb");
-      if (!fp_sig)
+      if (!direct_file_io)
         {
-          err = gpgme_error_from_syserror ();
-          fprintf (stderr, PGM ": can't open `%s': %s\n",
-                   argv[0], gpgme_strerror (err));
-          exit (1);
-        }
-      if (argc > 1)
-        {
-          fp_msg = fopen (argv[1], "rb");
-          if (!fp_msg)
+          fp_sig = fopen (argv[0], "rb");
+          if (!fp_sig)
             {
               err = gpgme_error_from_syserror ();
               fprintf (stderr, PGM ": can't open `%s': %s\n",
-                       argv[1], gpgme_strerror (err));
+                       argv[0], gpgme_strerror (err));
               exit (1);
             }
+          if (argc > 1)
+            {
+              fp_msg = fopen (argv[1], "rb");
+              if (!fp_msg)
+                {
+                  err = gpgme_error_from_syserror ();
+                  fprintf (stderr, PGM ": can't open `%s': %s\n",
+                           argv[1], gpgme_strerror (err));
+                  exit (1);
+                }
+            }
         }
 
       err = gpgme_new (&ctx);
@@ -429,7 +439,10 @@ main (int argc, char **argv)
           fail_if_err (err);
         }
 
-      err = gpgme_data_new_from_stream (&sig, fp_sig);
+      if (direct_file_io)
+        err = gpgme_data_new (&sig);
+      else
+        err = gpgme_data_new_from_stream (&sig, fp_sig);
       if (err)
         {
           fprintf (stderr, PGM ": error allocating data object: %s\n",
@@ -437,15 +450,38 @@ main (int argc, char **argv)
           exit (1);
         }
       gpgme_data_set_encoding (sig, encoding);
-      if (fp_msg)
+      if (direct_file_io)
         {
-          err = gpgme_data_new_from_stream (&msg, fp_msg);
+          err = gpgme_data_set_file_name (sig, argv[0]);
+          if (err)
+            {
+              fprintf (stderr, PGM ": error setting file name (sig): %s\n",
+                       gpgme_strerror (err));
+              exit (1);
+            }
+        }
+      if (argc > 1)
+        {
+          if (direct_file_io)
+            err = gpgme_data_new (&msg);
+          else
+            err = gpgme_data_new_from_stream (&msg, fp_msg);
           if (err)
             {
               fprintf (stderr, PGM ": error allocating data object: %s\n",
                        gpgme_strerror (err));
               exit (1);
             }
+          if (direct_file_io)
+            {
+              err = gpgme_data_set_file_name (msg, argv[1]);
+              if (err)
+                {
+                  fprintf (stderr, PGM ": error setting file name (msg): %s\n",
+                           gpgme_strerror (err));
+                  exit (1);
+                }
+            }
         }
 
       if (directory && (flags & GPGME_VERIFY_ARCHIVE))
@@ -454,14 +490,14 @@ main (int argc, char **argv)
           if (err)
             {
               fprintf (stderr, PGM ": error allocating data object: %s\n",
-                      gpgme_strerror (err));
+                       gpgme_strerror (err));
               exit (1);
             }
           err = gpgme_data_set_file_name (out, directory);
           if (err)
             {
               fprintf (stderr, PGM ": error setting file name (out): %s\n",
-                      gpgme_strerror (err));
+                       gpgme_strerror (err));
               exit (1);
             }
         }