wkd: Implement --blacklist option for gpg-wks-client

* tools/gpg-wks-client.c (blacklist_array, blacklist_array_len): New.
(parse_arguments): Install blacklist.
(read_file): New.
(cmp_blacklist, add_blacklist, is_in_blacklist): New.
(mirror_one_key): Check list.
* tools/gpg-wks.h (opt): Remove field blacklist.
--

GnuPG-bug-id: 6224
(cherry picked from commit b0b4e24c4fa80c10d310a229f5a0c65a57ad9393)

doc/wks.texi

@@ -53,6 +53,26 @@ Directory.
 .B gpg-wks-client
 .RI [ options ]
 .B \-\-read
+.br
+.B gpg-wks-client
+.RI [ options ]
+.B \-\-mirror
+.br
+.B gpg-wks-client
+.RI [ options ]
+.B \-\-install-key
+.br
+.B gpg-wks-client
+.RI [ options ]
+.B \-\-remove-key
+.br
+.B gpg-wks-client
+.RI [ options ]
+.B \-\-print-wkd-hash
+.br
+.B gpg-wks-client
+.RI [ options ]
+.B \-\-print-wkd-url
 @end ifset
 
 @mansect description
@@ -101,6 +121,13 @@ fingerprint and the mailbox separated by a space.  The command
 @option{--remove-key} removes a key from that directory, its only
 argument is a user-id.
 
+The command @option{--mirror} is similar to @option{--install-key} but
+takes the keys from the the LDAP server configured for Dirmngr.  If no
+arguments are given all keys and user ids are installed.  If arguments
+are given they are taken as domain names to limit the to be installed
+keys.  The option @option{--blacklist} may be used to further limit
+the to be installed keys.
+
 The command @option{--print-wkd-hash} prints the WKD user-id identifiers
 and the corresponding mailboxes from the user-ids given on the command
 line or via stdin (one user-id per line).
@@ -184,8 +211,16 @@ easily get the return code of the process.
 @itemx --directory @var{dir}
 @opindex directory
 Use @var{dir} as top level directory for the commands
-@option{--install-key} and @option{--remove-key}.  The default is
-@file{openpgpkey}.
+@option{--mirror}, @option{--install-key} and @option{--remove-key}.
+The default is @file{openpgpkey}.
+
+
+@item --blacklist @var{file}
+@opindex blacklist
+This option is used to exclude certain mail addresses from a mirror
+operation.  The format of @var{file} is one mail address (just the
+addrspec, e.g. "postel@@isi.edu") per line.  Empty lines and lines
+starting with a '#' are ignored.
 
 @item --verbose
 @opindex verbose

tools/gpg-wks-client.c

@@ -142,8 +142,14 @@ static struct debug_flags_s debug_flags [] =
 /* Value of the option --fake-submission-addr.  */
 const char *fake_submission_addr;
 
+/* An array with blacklisted addresses and its length.  Use
+ * is_in_blacklist to check.  */
+static char **blacklist_array;
+static size_t blacklist_array_len;
+
 
 static void wrong_args (const char *text) GPGRT_ATTR_NORETURN;
+static void add_blacklist (const char *fname);
 static gpg_error_t proc_userid_from_stdin (gpg_error_t (*func)(const char *),
                                            const char *text);
 static gpg_error_t command_supported (char *userid);
@@ -246,7 +252,7 @@ parse_arguments (ARGPARSE_ARGS *pargs, ARGPARSE_OPTS *popts)
           opt.no_autostart = 1;
           break;
         case oBlacklist:
-          opt.blacklist = pargs->r.ret_str;
+          add_blacklist (pargs->r.ret_str);
           break;
 
 	case aSupported:
@@ -465,6 +471,153 @@ main (int argc, char **argv)
 }
 
 
+
+/* Read a file FNAME into a buffer and return that malloced buffer.
+ * Caller must free the buffer.  On error NULL is returned, on success
+ * the valid length of the buffer is stored at R_LENGTH.  The returned
+ * buffer is guaranteed to be Nul terminated.  */
+static char *
+read_file (const char *fname, size_t *r_length)
+{
+  estream_t fp;
+  char *buf;
+  size_t buflen;
+
+  if (!strcmp (fname, "-"))
+    {
+      size_t nread, bufsize = 0;
+
+      fp = es_stdin;
+      es_set_binary (fp);
+      buf = NULL;
+      buflen = 0;
+#define NCHUNK 32767
+      do
+        {
+          bufsize += NCHUNK;
+          if (!buf)
+            buf = xmalloc (bufsize+1);
+          else
+            buf = xrealloc (buf, bufsize+1);
+
+          nread = es_fread (buf+buflen, 1, NCHUNK, fp);
+          if (nread < NCHUNK && es_ferror (fp))
+            {
+              log_error ("error reading '[stdin]': %s\n", strerror (errno));
+              xfree (buf);
+              return NULL;
+            }
+          buflen += nread;
+        }
+      while (nread == NCHUNK);
+#undef NCHUNK
+    }
+  else
+    {
+      struct stat st;
+
+      fp = es_fopen (fname, "rb");
+      if (!fp)
+        {
+          log_error ("can't open '%s': %s\n", fname, strerror (errno));
+          return NULL;
+        }
+
+      if (fstat (es_fileno (fp), &st))
+        {
+          log_error ("can't stat '%s': %s\n", fname, strerror (errno));
+          es_fclose (fp);
+          return NULL;
+        }
+
+      buflen = st.st_size;
+      buf = xmalloc (buflen+1);
+      if (es_fread (buf, buflen, 1, fp) != 1)
+        {
+          log_error ("error reading '%s': %s\n", fname, strerror (errno));
+          es_fclose (fp);
+          xfree (buf);
+          return NULL;
+        }
+      es_fclose (fp);
+    }
+  buf[buflen] = 0;
+  if (r_length)
+    *r_length = buflen;
+  return buf;
+}
+
+
+static int
+cmp_blacklist (const void *arg_a, const void *arg_b)
+{
+  const char *a = *(const char **)arg_a;
+  const char *b = *(const char **)arg_b;
+  return strcmp (a, b);
+}
+
+
+/* Add a blacklist to our global table.  This is called during option
+ * parsing and thus any use of log_error will eventually stop further
+ * processing.  */
+static void
+add_blacklist (const char *fname)
+{
+  char *buffer;
+  char *p, *pend;
+  char **array;
+  size_t arraysize, arrayidx;
+
+  buffer = read_file (fname, NULL);
+  if (!buffer)
+    return;
+
+  /* Estimate the number of entries by counting the non-comment lines.  */
+  arraysize = 2; /* For the first and an extra NULL item.  */
+  for (p=buffer; *p; p++)
+    if (*p == '\n' && p[1] && p[1] != '#')
+      arraysize++;
+
+  array = xcalloc (arraysize, sizeof *array);
+  arrayidx = 0;
+
+  /* Loop over all lines.  */
+  for (p = buffer; p && *p; p = pend)
+    {
+      pend = strchr (p, '\n');
+      if (pend)
+        *pend++ = 0;
+      trim_spaces (p);
+      if (!*p || *p == '#' )
+        continue;
+      ascii_strlwr (p);
+      log_assert (arrayidx < arraysize);
+      array[arrayidx] = p;
+      arrayidx++;
+    }
+  log_assert (arrayidx < arraysize);
+
+  qsort (array, arrayidx, sizeof *array, cmp_blacklist);
+
+  blacklist_array = array;
+  blacklist_array_len = arrayidx;
+  gpgrt_annotate_leaked_object (buffer);
+  gpgrt_annotate_leaked_object (blacklist_array);
+}
+
+
+/* Return true if NAME is in a blacklist.  */
+static int
+is_in_blacklist (const char *name)
+{
+  if (!name || !blacklist_array)
+    return 0;
+  return !!bsearch (&name, blacklist_array, blacklist_array_len,
+                    sizeof *blacklist_array, cmp_blacklist);
+}
+
+
+
 /* Read user ids from stdin and call FUNC for each user id.  TEXT is
  * used for error messages.  */
 static gpg_error_t
@@ -1754,6 +1907,8 @@ mirror_one_key (estream_t key)
         continue; /* No mail box or already processed.  */
       if (!domain_matches_mbox (domain, uid->mbox))
         continue; /* We don't want this one.  */
+      if (is_in_blacklist (uid->mbox))
+        continue;
 
       err = mirror_one_keys_userid (key, uid->mbox, uidlist, fpr);
       if (err)

tools/gpg-wks.h

@@ -44,7 +44,6 @@ struct
   const char *directory;
   const char *default_from;
   strlist_t extra_headers;
-  const char *blacklist;
 } opt;
 
 /* Debug values and macros.  */