Add finger support to dirmngr.

The basic network code from http.c is used for finger.  This keeps the
network related code at one place and we are able to use the somewhat
matured code form http.c.  Unfortunately I had to enhance the http
code for more robustness and probably introduced new bugs.

Test this code using

  gpg --fetch-key finger:[email protected]

(I might be the last user of finger ;-)

1 files changed, 60 insertions, 1 deletions

diff --git a/g10/call-dirmngr.c b/g10/call-dirmngr.c
index 10c0e568c..09ade4eb9 100644
--- a/g10/call-dirmngr.c
+++ b/g10/call-dirmngr.c
@@ -354,7 +354,7 @@ gpg_dirmngr_ks_search (ctrl_t ctrl, const char *searchstr,
 
 
 
-/* Data callback for the KS_GET command. */
+/* Data callback for the KS_GET and KS_FETCH commands. */
 static gpg_error_t
 ks_get_data_cb (void *opaque, const void *data, size_t datalen)
 {
@@ -448,6 +448,65 @@ gpg_dirmngr_ks_get (ctrl_t ctrl, char **pattern, estream_t *r_fp)
 }
 
 
+/* Run the KS_FETCH and pass URL as argument.  On success an estream
+   object is returned to retrieve the keys.  On error an error code is
+   returned and NULL stored at R_FP.
+
+   The url is expected to point to a small set of keys; in many cases
+   only to one key.  However, schemes like finger may return several
+   keys.  Note that the configured keyservers are ignored by the
+   KS_FETCH command.  */
+gpg_error_t
+gpg_dirmngr_ks_fetch (ctrl_t ctrl, const char *url, estream_t *r_fp)
+{
+  gpg_error_t err;
+  assuan_context_t ctx;
+  struct ks_get_parm_s parm;
+  char *line = NULL;
+
+  memset (&parm, 0, sizeof parm);
+
+  *r_fp = NULL;
+
+  err = open_context (ctrl, &ctx);
+  if (err)
+    return err;
+
+  line = strconcat ("KS_FETCH -- ", url, NULL);
+  if (!line)
+    {
+      err = gpg_error_from_syserror ();
+      goto leave;
+    }
+  if (strlen (line) + 2 >= ASSUAN_LINELENGTH)
+    {
+      err = gpg_error (GPG_ERR_TOO_LARGE);
+      goto leave;
+    }
+
+  parm.memfp = es_fopenmem (0, "rwb");
+  if (!parm.memfp)
+    {
+      err = gpg_error_from_syserror ();
+      goto leave;
+    }
+  err = assuan_transact (ctx, line, ks_get_data_cb, &parm,
+                         NULL, NULL, NULL, NULL);
+  if (err)
+    goto leave;
+
+  es_rewind (parm.memfp);
+  *r_fp = parm.memfp;
+  parm.memfp = NULL;
+
+ leave:
+  es_fclose (parm.memfp);
+  xfree (line);
+  close_context (ctrl, ctx);
+  return err;
+}
+
+
 
 /* Handle the KS_PUT inquiries. */
 static gpg_error_t