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-rw-r--r--tools/gpg-wks-client.c1595
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diff --git a/tools/gpg-wks-client.c b/tools/gpg-wks-client.c
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+++ b/tools/gpg-wks-client.c
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+/* gpg-wks-client.c - A client for the Web Key Service protocols.
+ * Copyright (C) 2016 Werner Koch
+ * Copyright (C) 2016 Bundesamt für Sicherheit in der Informationstechnik
+ *
+ * This file is part of GnuPG.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#define INCLUDED_BY_MAIN_MODULE 1
+#include "../common/util.h"
+#include "../common/status.h"
+#include "../common/i18n.h"
+#include "../common/sysutils.h"
+#include "../common/init.h"
+#include "../common/asshelp.h"
+#include "../common/userids.h"
+#include "../common/ccparray.h"
+#include "../common/exectool.h"
+#include "../common/mbox-util.h"
+#include "../common/name-value.h"
+#include "call-dirmngr.h"
+#include "mime-maker.h"
+#include "send-mail.h"
+#include "gpg-wks.h"
+
+
+/* Constants to identify the commands and options. */
+enum cmd_and_opt_values
+ {
+ aNull = 0,
+
+ oQuiet = 'q',
+ oVerbose = 'v',
+ oOutput = 'o',
+ oDirectory = 'C',
+
+ oDebug = 500,
+
+ aSupported,
+ aCheck,
+ aCreate,
+ aReceive,
+ aRead,
+ aInstallKey,
+ aRemoveKey,
+ aPrintWKDHash,
+ aPrintWKDURL,
+
+ oGpgProgram,
+ oSend,
+ oFakeSubmissionAddr,
+ oStatusFD,
+ oWithColons,
+
+ oDummy
+ };
+
+
+/* The list of commands and options. */
+static ARGPARSE_OPTS opts[] = {
+ ARGPARSE_group (300, ("@Commands:\n ")),
+
+ ARGPARSE_c (aSupported, "supported",
+ ("check whether provider supports WKS")),
+ ARGPARSE_c (aCheck, "check",
+ ("check whether a key is available")),
+ ARGPARSE_c (aCreate, "create",
+ ("create a publication request")),
+ ARGPARSE_c (aReceive, "receive",
+ ("receive a MIME confirmation request")),
+ ARGPARSE_c (aRead, "read",
+ ("receive a plain text confirmation request")),
+ ARGPARSE_c (aInstallKey, "install-key",
+ "install a key into a directory"),
+ ARGPARSE_c (aRemoveKey, "remove-key",
+ "remove a key from a directory"),
+ ARGPARSE_c (aPrintWKDHash, "print-wkd-hash",
+ "Print the WKD identifier for the given user ids"),
+ ARGPARSE_c (aPrintWKDURL, "print-wkd-url",
+ "Print the WKD URL for the given user id"),
+
+ ARGPARSE_group (301, ("@\nOptions:\n ")),
+
+ ARGPARSE_s_n (oVerbose, "verbose", ("verbose")),
+ ARGPARSE_s_n (oQuiet, "quiet", ("be somewhat more quiet")),
+ ARGPARSE_s_s (oDebug, "debug", "@"),
+ ARGPARSE_s_s (oGpgProgram, "gpg", "@"),
+ ARGPARSE_s_n (oSend, "send", "send the mail using sendmail"),
+ ARGPARSE_s_s (oOutput, "output", "|FILE|write the mail to FILE"),
+ ARGPARSE_s_i (oStatusFD, "status-fd", N_("|FD|write status info to this FD")),
+ ARGPARSE_s_n (oWithColons, "with-colons", "@"),
+ ARGPARSE_s_s (oDirectory, "directory", "@"),
+
+ ARGPARSE_s_s (oFakeSubmissionAddr, "fake-submission-addr", "@"),
+
+ ARGPARSE_end ()
+};
+
+
+/* The list of supported debug flags. */
+static struct debug_flags_s debug_flags [] =
+ {
+ { DBG_MIME_VALUE , "mime" },
+ { DBG_PARSER_VALUE , "parser" },
+ { DBG_CRYPTO_VALUE , "crypto" },
+ { DBG_MEMORY_VALUE , "memory" },
+ { DBG_MEMSTAT_VALUE, "memstat" },
+ { DBG_IPC_VALUE , "ipc" },
+ { DBG_EXTPROG_VALUE, "extprog" },
+ { 0, NULL }
+ };
+
+
+
+/* Value of the option --fake-submission-addr. */
+const char *fake_submission_addr;
+
+
+static void wrong_args (const char *text) GPGRT_ATTR_NORETURN;
+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);
+static gpg_error_t command_check (char *userid);
+static gpg_error_t command_send (const char *fingerprint, const char *userid);
+static gpg_error_t encrypt_response (estream_t *r_output, estream_t input,
+ const char *addrspec,
+ const char *fingerprint);
+static gpg_error_t read_confirmation_request (estream_t msg);
+static gpg_error_t command_receive_cb (void *opaque,
+ const char *mediatype, estream_t fp,
+ unsigned int flags);
+
+
+
+/* Print usage information and provide strings for help. */
+static const char *
+my_strusage( int level )
+{
+ const char *p;
+
+ switch (level)
+ {
+ case 9: p = "LGPL-2.1-or-later"; break;
+ case 11: p = "gpg-wks-client"; break;
+ case 12: p = "@GNUPG@"; break;
+ case 13: p = VERSION; break;
+ case 14: p = GNUPG_DEF_COPYRIGHT_LINE; break;
+ case 17: p = PRINTABLE_OS_NAME; break;
+ case 19: p = ("Please report bugs to <@EMAIL@>.\n"); break;
+
+ case 1:
+ case 40:
+ p = ("Usage: gpg-wks-client [command] [options] [args] (-h for help)");
+ break;
+ case 41:
+ p = ("Syntax: gpg-wks-client [command] [options] [args]\n"
+ "Client for the Web Key Service\n");
+ break;
+
+ default: p = NULL; break;
+ }
+ return p;
+}
+
+
+static void
+wrong_args (const char *text)
+{
+ es_fprintf (es_stderr, _("usage: %s [options] %s\n"), strusage (11), text);
+ exit (2);
+}
+
+
+
+/* Command line parsing. */
+static enum cmd_and_opt_values
+parse_arguments (ARGPARSE_ARGS *pargs, ARGPARSE_OPTS *popts)
+{
+ enum cmd_and_opt_values cmd = 0;
+ int no_more_options = 0;
+
+ while (!no_more_options && gnupg_argparse (NULL, pargs, popts))
+ {
+ switch (pargs->r_opt)
+ {
+ case oQuiet: opt.quiet = 1; break;
+ case oVerbose: opt.verbose++; break;
+ case oDebug:
+ if (parse_debug_flag (pargs->r.ret_str, &opt.debug, debug_flags))
+ {
+ pargs->r_opt = ARGPARSE_INVALID_ARG;
+ pargs->err = ARGPARSE_PRINT_ERROR;
+ }
+ break;
+
+ case oGpgProgram:
+ opt.gpg_program = pargs->r.ret_str;
+ break;
+ case oDirectory:
+ opt.directory = pargs->r.ret_str;
+ break;
+ case oSend:
+ opt.use_sendmail = 1;
+ break;
+ case oOutput:
+ opt.output = pargs->r.ret_str;
+ break;
+ case oFakeSubmissionAddr:
+ fake_submission_addr = pargs->r.ret_str;
+ break;
+ case oStatusFD:
+ wks_set_status_fd (translate_sys2libc_fd_int (pargs->r.ret_int, 1));
+ break;
+ case oWithColons:
+ opt.with_colons = 1;
+ break;
+
+ case aSupported:
+ case aCreate:
+ case aReceive:
+ case aRead:
+ case aCheck:
+ case aInstallKey:
+ case aRemoveKey:
+ case aPrintWKDHash:
+ case aPrintWKDURL:
+ cmd = pargs->r_opt;
+ break;
+
+ default: pargs->err = ARGPARSE_PRINT_ERROR; break;
+ }
+ }
+
+ return cmd;
+}
+
+
+
+/* gpg-wks-client main. */
+int
+main (int argc, char **argv)
+{
+ gpg_error_t err, delayed_err;
+ ARGPARSE_ARGS pargs;
+ enum cmd_and_opt_values cmd;
+
+ gnupg_reopen_std ("gpg-wks-client");
+ set_strusage (my_strusage);
+ log_set_prefix ("gpg-wks-client", GPGRT_LOG_WITH_PREFIX);
+
+ /* Make sure that our subsystems are ready. */
+ i18n_init();
+ init_common_subsystems (&argc, &argv);
+
+ assuan_set_gpg_err_source (GPG_ERR_SOURCE_DEFAULT);
+ setup_libassuan_logging (&opt.debug, NULL);
+
+ /* Parse the command line. */
+ pargs.argc = &argc;
+ pargs.argv = &argv;
+ pargs.flags = ARGPARSE_FLAG_KEEP;
+ cmd = parse_arguments (&pargs, opts);
+ gnupg_argparse (NULL, &pargs, NULL);
+
+ if (log_get_errorcount (0))
+ exit (2);
+
+ /* Print a warning if an argument looks like an option. */
+ if (!opt.quiet && !(pargs.flags & ARGPARSE_FLAG_STOP_SEEN))
+ {
+ int i;
+
+ for (i=0; i < argc; i++)
+ if (argv[i][0] == '-' && argv[i][1] == '-')
+ log_info (("NOTE: '%s' is not considered an option\n"), argv[i]);
+ }
+
+ /* Set defaults for non given options. */
+ if (!opt.gpg_program)
+ opt.gpg_program = gnupg_module_name (GNUPG_MODULE_NAME_GPG);
+
+ if (!opt.directory)
+ opt.directory = "openpgpkey";
+
+ /* Tell call-dirmngr what options we want. */
+ set_dirmngr_options (opt.verbose, (opt.debug & DBG_IPC_VALUE), 1);
+
+
+ /* Check that the top directory exists. */
+ if (cmd == aInstallKey || cmd == aRemoveKey)
+ {
+ struct stat sb;
+
+ if (gnupg_stat (opt.directory, &sb))
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error accessing directory '%s': %s\n",
+ opt.directory, gpg_strerror (err));
+ goto leave;
+ }
+ if (!S_ISDIR(sb.st_mode))
+ {
+ log_error ("error accessing directory '%s': %s\n",
+ opt.directory, "not a directory");
+ err = gpg_error (GPG_ERR_ENOENT);
+ goto leave;
+ }
+ }
+
+ /* Run the selected command. */
+ switch (cmd)
+ {
+ case aSupported:
+ if (opt.with_colons)
+ {
+ for (; argc; argc--, argv++)
+ command_supported (*argv);
+ err = 0;
+ }
+ else
+ {
+ if (argc != 1)
+ wrong_args ("--supported DOMAIN");
+ err = command_supported (argv[0]);
+ if (err && gpg_err_code (err) != GPG_ERR_FALSE)
+ log_error ("checking support failed: %s\n", gpg_strerror (err));
+ }
+ break;
+
+ case aCreate:
+ if (argc != 2)
+ wrong_args ("--create FINGERPRINT USER-ID");
+ err = command_send (argv[0], argv[1]);
+ if (err)
+ log_error ("creating request failed: %s\n", gpg_strerror (err));
+ break;
+
+ case aReceive:
+ if (argc)
+ wrong_args ("--receive < MIME-DATA");
+ err = wks_receive (es_stdin, command_receive_cb, NULL);
+ if (err)
+ log_error ("processing mail failed: %s\n", gpg_strerror (err));
+ break;
+
+ case aRead:
+ if (argc)
+ wrong_args ("--read < WKS-DATA");
+ err = read_confirmation_request (es_stdin);
+ if (err)
+ log_error ("processing mail failed: %s\n", gpg_strerror (err));
+ break;
+
+ case aCheck:
+ if (argc != 1)
+ wrong_args ("--check USER-ID");
+ err = command_check (argv[0]);
+ break;
+
+ case aInstallKey:
+ if (!argc)
+ err = wks_cmd_install_key (NULL, NULL);
+ else if (argc == 2)
+ err = wks_cmd_install_key (*argv, argv[1]);
+ else
+ wrong_args ("--install-key [FILE|FINGERPRINT USER-ID]");
+ break;
+
+ case aRemoveKey:
+ if (argc != 1)
+ wrong_args ("--remove-key USER-ID");
+ err = wks_cmd_remove_key (*argv);
+ break;
+
+ case aPrintWKDHash:
+ case aPrintWKDURL:
+ if (!argc)
+ {
+ if (cmd == aPrintWKDHash)
+ err = proc_userid_from_stdin (wks_cmd_print_wkd_hash,
+ "printing WKD hash");
+ else
+ err = proc_userid_from_stdin (wks_cmd_print_wkd_url,
+ "printing WKD URL");
+ }
+ else
+ {
+ for (err = delayed_err = 0; !err && argc; argc--, argv++)
+ {
+ if (cmd == aPrintWKDHash)
+ err = wks_cmd_print_wkd_hash (*argv);
+ else
+ err = wks_cmd_print_wkd_url (*argv);
+ if (gpg_err_code (err) == GPG_ERR_INV_USER_ID)
+ {
+ /* Diagnostic already printed. */
+ delayed_err = err;
+ err = 0;
+ }
+ else if (err)
+ log_error ("printing hash failed: %s\n", gpg_strerror (err));
+ }
+ if (!err)
+ err = delayed_err;
+ }
+ break;
+
+ default:
+ usage (1);
+ err = 0;
+ break;
+ }
+
+ leave:
+ if (err)
+ wks_write_status (STATUS_FAILURE, "- %u", err);
+ else if (log_get_errorcount (0))
+ wks_write_status (STATUS_FAILURE, "- %u", GPG_ERR_GENERAL);
+ else
+ wks_write_status (STATUS_SUCCESS, NULL);
+ return (err || log_get_errorcount (0))? 1:0;
+}
+
+
+/* Read user ids from stdin and call FUNC for each user id. TEXT is
+ * used for error messages. */
+static gpg_error_t
+proc_userid_from_stdin (gpg_error_t (*func)(const char *), const char *text)
+{
+ gpg_error_t err = 0;
+ gpg_error_t delayed_err = 0;
+ char line[2048];
+ size_t n = 0;
+
+ /* If we are on a terminal disable buffering to get direct response. */
+ if (gnupg_isatty (es_fileno (es_stdin))
+ && gnupg_isatty (es_fileno (es_stdout)))
+ {
+ es_setvbuf (es_stdin, NULL, _IONBF, 0);
+ es_setvbuf (es_stdout, NULL, _IOLBF, 0);
+ }
+
+ while (es_fgets (line, sizeof line - 1, es_stdin))
+ {
+ n = strlen (line);
+ if (!n || line[n-1] != '\n')
+ {
+ err = gpg_error (*line? GPG_ERR_LINE_TOO_LONG
+ : GPG_ERR_INCOMPLETE_LINE);
+ log_error ("error reading stdin: %s\n", gpg_strerror (err));
+ break;
+ }
+ trim_spaces (line);
+ err = func (line);
+ if (gpg_err_code (err) == GPG_ERR_INV_USER_ID)
+ {
+ delayed_err = err;
+ err = 0;
+ }
+ else if (err)
+ log_error ("%s failed: %s\n", text, gpg_strerror (err));
+ }
+ if (es_ferror (es_stdin))
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error reading stdin: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+
+ leave:
+ if (!err)
+ err = delayed_err;
+ return err;
+}
+
+
+
+
+/* Add the user id UID to the key identified by FINGERPRINT. */
+static gpg_error_t
+add_user_id (const char *fingerprint, const char *uid)
+{
+ gpg_error_t err;
+ ccparray_t ccp;
+ const char **argv = NULL;
+
+ ccparray_init (&ccp, 0);
+
+ ccparray_put (&ccp, "--no-options");
+ if (!opt.verbose)
+ ccparray_put (&ccp, "--quiet");
+ else if (opt.verbose > 1)
+ ccparray_put (&ccp, "--verbose");
+ ccparray_put (&ccp, "--batch");
+ ccparray_put (&ccp, "--always-trust");
+ ccparray_put (&ccp, "--quick-add-uid");
+ ccparray_put (&ccp, fingerprint);
+ ccparray_put (&ccp, uid);
+
+ ccparray_put (&ccp, NULL);
+ argv = ccparray_get (&ccp, NULL);
+ if (!argv)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ err = gnupg_exec_tool_stream (opt.gpg_program, argv, NULL,
+ NULL, NULL,
+ NULL, NULL);
+ if (err)
+ {
+ log_error ("adding user id failed: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+
+ leave:
+ xfree (argv);
+ return err;
+}
+
+
+
+struct decrypt_stream_parm_s
+{
+ char *fpr;
+ char *mainfpr;
+ int otrust;
+};
+
+static void
+decrypt_stream_status_cb (void *opaque, const char *keyword, char *args)
+{
+ struct decrypt_stream_parm_s *decinfo = opaque;
+
+ if (DBG_CRYPTO)
+ log_debug ("gpg status: %s %s\n", keyword, args);
+ if (!strcmp (keyword, "DECRYPTION_KEY") && !decinfo->fpr)
+ {
+ char *fields[3];
+
+ if (split_fields (args, fields, DIM (fields)) >= 3)
+ {
+ decinfo->fpr = xstrdup (fields[0]);
+ decinfo->mainfpr = xstrdup (fields[1]);
+ decinfo->otrust = *fields[2];
+ }
+ }
+}
+
+/* Decrypt the INPUT stream to a new stream which is stored at success
+ * at R_OUTPUT. */
+static gpg_error_t
+decrypt_stream (estream_t *r_output, struct decrypt_stream_parm_s *decinfo,
+ estream_t input)
+{
+ gpg_error_t err;
+ ccparray_t ccp;
+ const char **argv;
+ estream_t output;
+
+ *r_output = NULL;
+ memset (decinfo, 0, sizeof *decinfo);
+
+ output = es_fopenmem (0, "w+b");
+ if (!output)
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error allocating memory buffer: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ ccparray_init (&ccp, 0);
+
+ ccparray_put (&ccp, "--no-options");
+ /* We limit the output to 64 KiB to avoid DoS using compression
+ * tricks. A regular client will anyway only send a minimal key;
+ * that is one w/o key signatures and attribute packets. */
+ ccparray_put (&ccp, "--max-output=0x10000");
+ if (!opt.verbose)
+ ccparray_put (&ccp, "--quiet");
+ else if (opt.verbose > 1)
+ ccparray_put (&ccp, "--verbose");
+ ccparray_put (&ccp, "--batch");
+ ccparray_put (&ccp, "--status-fd=2");
+ ccparray_put (&ccp, "--decrypt");
+ ccparray_put (&ccp, "--");
+
+ ccparray_put (&ccp, NULL);
+ argv = ccparray_get (&ccp, NULL);
+ if (!argv)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ err = gnupg_exec_tool_stream (opt.gpg_program, argv, input,
+ NULL, output,
+ decrypt_stream_status_cb, decinfo);
+ if (!err && (!decinfo->fpr || !decinfo->mainfpr || !decinfo->otrust))
+ err = gpg_error (GPG_ERR_INV_ENGINE);
+ if (err)
+ {
+ log_error ("decryption failed: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+ else if (opt.verbose)
+ log_info ("decryption succeeded\n");
+
+ es_rewind (output);
+ *r_output = output;
+ output = NULL;
+
+ leave:
+ if (err)
+ {
+ xfree (decinfo->fpr);
+ xfree (decinfo->mainfpr);
+ memset (decinfo, 0, sizeof *decinfo);
+ }
+ es_fclose (output);
+ xfree (argv);
+ return err;
+}
+
+
+/* Return the submission address for the address or just the domain in
+ * ADDRSPEC. The submission address is stored as a malloced string at
+ * R_SUBMISSION_ADDRESS. At R_POLICY the policy flags of the domain
+ * are stored. The caller needs to free them with wks_free_policy.
+ * The function returns an error code on failure to find a submission
+ * address or policy file. Note: The function may store NULL at
+ * R_SUBMISSION_ADDRESS but return success to indicate that the web
+ * key directory is supported but not the web key service. As per WKD
+ * specs a policy file is always required and will thus be return on
+ * success. */
+static gpg_error_t
+get_policy_and_sa (const char *addrspec, int silent,
+ policy_flags_t *r_policy, char **r_submission_address)
+{
+ gpg_error_t err;
+ estream_t mbuf = NULL;
+ const char *domain;
+ const char *s;
+ policy_flags_t policy = NULL;
+ char *submission_to = NULL;
+
+ *r_submission_address = NULL;
+ *r_policy = NULL;
+
+ domain = strchr (addrspec, '@');
+ if (domain)
+ domain++;
+
+ if (opt.with_colons)
+ {
+ s = domain? domain : addrspec;
+ es_write_sanitized (es_stdout, s, strlen (s), ":", NULL);
+ es_putc (':', es_stdout);
+ }
+
+ /* We first try to get the submission address from the policy file
+ * (this is the new method). If both are available we check that
+ * they match and print a warning if not. In the latter case we
+ * keep on using the one from the submission-address file. */
+ err = wkd_get_policy_flags (addrspec, &mbuf);
+ if (err && gpg_err_code (err) != GPG_ERR_NO_DATA
+ && gpg_err_code (err) != GPG_ERR_NO_NAME)
+ {
+ if (!opt.with_colons)
+ log_error ("error reading policy flags for '%s': %s\n",
+ domain, gpg_strerror (err));
+ goto leave;
+ }
+ if (!mbuf)
+ {
+ if (!opt.with_colons)
+ log_error ("provider for '%s' does NOT support the Web Key Directory\n",
+ addrspec);
+ err = gpg_error (GPG_ERR_FALSE);
+ goto leave;
+ }
+
+ policy = xtrycalloc (1, sizeof *policy);
+ if (!policy)
+ err = gpg_error_from_syserror ();
+ else
+ err = wks_parse_policy (policy, mbuf, 1);
+ es_fclose (mbuf);
+ mbuf = NULL;
+ if (err)
+ goto leave;
+
+ err = wkd_get_submission_address (addrspec, &submission_to);
+ if (err && !policy->submission_address)
+ {
+ if (!silent && !opt.with_colons)
+ log_error (_("error looking up submission address for domain '%s'"
+ ": %s\n"), domain, gpg_strerror (err));
+ if (!silent && gpg_err_code (err) == GPG_ERR_NO_DATA && !opt.with_colons)
+ log_error (_("this domain probably doesn't support WKS.\n"));
+ goto leave;
+ }
+
+ if (submission_to && policy->submission_address
+ && ascii_strcasecmp (submission_to, policy->submission_address))
+ log_info ("Warning: different submission addresses (sa=%s, po=%s)\n",
+ submission_to, policy->submission_address);
+
+ if (!submission_to && policy->submission_address)
+ {
+ submission_to = xtrystrdup (policy->submission_address);
+ if (!submission_to)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ }
+
+ leave:
+ *r_submission_address = submission_to;
+ submission_to = NULL;
+ *r_policy = policy;
+ policy = NULL;
+
+ if (opt.with_colons)
+ {
+ if (*r_policy && !*r_submission_address)
+ es_fprintf (es_stdout, "1:0::");
+ else if (*r_policy && *r_submission_address)
+ es_fprintf (es_stdout, "1:1::");
+ else if (err && !(gpg_err_code (err) == GPG_ERR_FALSE
+ || gpg_err_code (err) == GPG_ERR_NO_DATA
+ || gpg_err_code (err) == GPG_ERR_UNKNOWN_HOST))
+ es_fprintf (es_stdout, "0:0:%d:", err);
+ else
+ es_fprintf (es_stdout, "0:0::");
+ if (*r_policy)
+ {
+ es_fprintf (es_stdout, "%u:%u:%u:",
+ (*r_policy)->protocol_version,
+ (*r_policy)->auth_submit,
+ (*r_policy)->mailbox_only);
+ }
+ es_putc ('\n', es_stdout);
+ }
+
+ xfree (submission_to);
+ wks_free_policy (policy);
+ xfree (policy);
+ es_fclose (mbuf);
+ return err;
+}
+
+
+
+/* Check whether the provider supports the WKS protocol. */
+static gpg_error_t
+command_supported (char *userid)
+{
+ gpg_error_t err;
+ char *addrspec = NULL;
+ char *submission_to = NULL;
+ policy_flags_t policy = NULL;
+
+ if (!strchr (userid, '@'))
+ {
+ char *tmp = xstrconcat ("foo@", userid, NULL);
+ addrspec = mailbox_from_userid (tmp);
+ xfree (tmp);
+ }
+ else
+ addrspec = mailbox_from_userid (userid);
+ if (!addrspec)
+ {
+ log_error (_("\"%s\" is not a proper mail address\n"), userid);
+ err = gpg_error (GPG_ERR_INV_USER_ID);
+ goto leave;
+ }
+
+ /* Get the submission address. */
+ err = get_policy_and_sa (addrspec, 1, &policy, &submission_to);
+ if (err || !submission_to)
+ {
+ if (!submission_to
+ || gpg_err_code (err) == GPG_ERR_FALSE
+ || gpg_err_code (err) == GPG_ERR_NO_DATA
+ || gpg_err_code (err) == GPG_ERR_UNKNOWN_HOST
+ )
+ {
+ /* FALSE is returned if we already figured out that even the
+ * Web Key Directory is not supported and thus printed an
+ * error message. */
+ if (opt.verbose && gpg_err_code (err) != GPG_ERR_FALSE
+ && !opt.with_colons)
+ {
+ if (gpg_err_code (err) == GPG_ERR_NO_DATA)
+ log_info ("provider for '%s' does NOT support WKS\n",
+ addrspec);
+ else
+ log_info ("provider for '%s' does NOT support WKS (%s)\n",
+ addrspec, gpg_strerror (err));
+ }
+ err = gpg_error (GPG_ERR_FALSE);
+ if (!opt.with_colons)
+ log_inc_errorcount ();
+ }
+ goto leave;
+ }
+
+ if (opt.verbose && !opt.with_colons)
+ log_info ("provider for '%s' supports WKS\n", addrspec);
+
+ leave:
+ wks_free_policy (policy);
+ xfree (policy);
+ xfree (submission_to);
+ xfree (addrspec);
+ return err;
+}
+
+
+
+/* Check whether the key for USERID is available in the WKD. */
+static gpg_error_t
+command_check (char *userid)
+{
+ gpg_error_t err;
+ char *addrspec = NULL;
+ estream_t key = NULL;
+ char *fpr = NULL;
+ uidinfo_list_t mboxes = NULL;
+ uidinfo_list_t sl;
+ int found = 0;
+
+ addrspec = mailbox_from_userid (userid);
+ if (!addrspec)
+ {
+ log_error (_("\"%s\" is not a proper mail address\n"), userid);
+ err = gpg_error (GPG_ERR_INV_USER_ID);
+ goto leave;
+ }
+
+ /* Get the submission address. */
+ err = wkd_get_key (addrspec, &key);
+ switch (gpg_err_code (err))
+ {
+ case 0:
+ if (opt.verbose)
+ log_info ("public key for '%s' found via WKD\n", addrspec);
+ /* Fixme: Check that the key contains the user id. */
+ break;
+
+ case GPG_ERR_NO_DATA: /* No such key. */
+ if (opt.verbose)
+ log_info ("public key for '%s' NOT found via WKD\n", addrspec);
+ err = gpg_error (GPG_ERR_NO_PUBKEY);
+ log_inc_errorcount ();
+ break;
+
+ case GPG_ERR_UNKNOWN_HOST:
+ if (opt.verbose)
+ log_info ("error looking up '%s' via WKD: %s\n",
+ addrspec, gpg_strerror (err));
+ err = gpg_error (GPG_ERR_NOT_SUPPORTED);
+ break;
+
+ default:
+ log_error ("error looking up '%s' via WKD: %s\n",
+ addrspec, gpg_strerror (err));
+ break;
+ }
+
+ if (err)
+ goto leave;
+
+ /* Look closer at the key. */
+ err = wks_list_key (key, &fpr, &mboxes);
+ if (err)
+ {
+ log_error ("error parsing key: %s\n", gpg_strerror (err));
+ err = gpg_error (GPG_ERR_NO_PUBKEY);
+ goto leave;
+ }
+
+ if (opt.verbose)
+ log_info ("fingerprint: %s\n", fpr);
+
+ for (sl = mboxes; sl; sl = sl->next)
+ {
+ if (sl->mbox && !strcmp (sl->mbox, addrspec))
+ found = 1;
+ if (opt.verbose)
+ {
+ log_info (" user-id: %s\n", sl->uid);
+ log_info (" created: %s\n", asctimestamp (sl->created));
+ if (sl->mbox)
+ log_info (" addr-spec: %s\n", sl->mbox);
+ }
+ }
+ if (!found)
+ {
+ log_error ("public key for '%s' has no user id with the mail address\n",
+ addrspec);
+ err = gpg_error (GPG_ERR_CERT_REVOKED);
+ }
+
+ leave:
+ xfree (fpr);
+ free_uidinfo_list (mboxes);
+ es_fclose (key);
+ xfree (addrspec);
+ return err;
+}
+
+
+
+/* Locate the key by fingerprint and userid and send a publication
+ * request. */
+static gpg_error_t
+command_send (const char *fingerprint, const char *userid)
+{
+ gpg_error_t err;
+ KEYDB_SEARCH_DESC desc;
+ char *addrspec = NULL;
+ estream_t key = NULL;
+ estream_t keyenc = NULL;
+ char *submission_to = NULL;
+ mime_maker_t mime = NULL;
+ policy_flags_t policy = NULL;
+ int no_encrypt = 0;
+ int posteo_hack = 0;
+ const char *domain;
+ uidinfo_list_t uidlist = NULL;
+ uidinfo_list_t uid, thisuid;
+ time_t thistime;
+
+ if (classify_user_id (fingerprint, &desc, 1)
+ || !(desc.mode == KEYDB_SEARCH_MODE_FPR
+ || desc.mode == KEYDB_SEARCH_MODE_FPR20))
+ {
+ log_error (_("\"%s\" is not a fingerprint\n"), fingerprint);
+ err = gpg_error (GPG_ERR_INV_NAME);
+ goto leave;
+ }
+
+ addrspec = mailbox_from_userid (userid);
+ if (!addrspec)
+ {
+ log_error (_("\"%s\" is not a proper mail address\n"), userid);
+ err = gpg_error (GPG_ERR_INV_USER_ID);
+ goto leave;
+ }
+ err = wks_get_key (&key, fingerprint, addrspec, 0);
+ if (err)
+ goto leave;
+
+ domain = strchr (addrspec, '@');
+ log_assert (domain);
+ domain++;
+
+ /* Get the submission address. */
+ if (fake_submission_addr)
+ {
+ policy = xcalloc (1, sizeof *policy);
+ submission_to = xstrdup (fake_submission_addr);
+ err = 0;
+ }
+ else
+ {
+ err = get_policy_and_sa (addrspec, 0, &policy, &submission_to);
+ if (err)
+ goto leave;
+ if (!submission_to)
+ {
+ log_error (_("this domain probably doesn't support WKS.\n"));
+ err = gpg_error (GPG_ERR_NO_DATA);
+ goto leave;
+ }
+ }
+
+ log_info ("submitting request to '%s'\n", submission_to);
+
+ if (policy->auth_submit)
+ log_info ("no confirmation required for '%s'\n", addrspec);
+
+ /* In case the key has several uids with the same addr-spec we will
+ * use the newest one. */
+ err = wks_list_key (key, NULL, &uidlist);
+ if (err)
+ {
+ log_error ("error parsing key: %s\n",gpg_strerror (err));
+ err = gpg_error (GPG_ERR_NO_PUBKEY);
+ goto leave;
+ }
+ thistime = 0;
+ thisuid = NULL;
+ for (uid = uidlist; uid; uid = uid->next)
+ {
+ if (!uid->mbox)
+ continue; /* Should not happen anyway. */
+ if (policy->mailbox_only && ascii_strcasecmp (uid->uid, uid->mbox))
+ continue; /* UID has more than just the mailbox. */
+ if (uid->created > thistime)
+ {
+ thistime = uid->created;
+ thisuid = uid;
+ }
+ }
+ if (!thisuid)
+ thisuid = uidlist; /* This is the case for a missing timestamp. */
+ if (opt.verbose)
+ log_info ("submitting key with user id '%s'\n", thisuid->uid);
+
+ /* If we have more than one user id we need to filter the key to
+ * include only THISUID. */
+ if (uidlist->next)
+ {
+ estream_t newkey;
+
+ es_rewind (key);
+ err = wks_filter_uid (&newkey, key, thisuid->uid, 0);
+ if (err)
+ {
+ log_error ("error filtering key: %s\n", gpg_strerror (err));
+ err = gpg_error (GPG_ERR_NO_PUBKEY);
+ goto leave;
+ }
+ es_fclose (key);
+ key = newkey;
+ }
+
+ if (policy->mailbox_only
+ && (!thisuid->mbox || ascii_strcasecmp (thisuid->uid, thisuid->mbox)))
+ {
+ log_info ("Warning: policy requires 'mailbox-only'"
+ " - adding user id '%s'\n", addrspec);
+ err = add_user_id (fingerprint, addrspec);
+ if (err)
+ goto leave;
+
+ /* Need to get the key again. This time we request filtering
+ * for the full user id, so that we do not need check and filter
+ * the key again. */
+ es_fclose (key);
+ key = NULL;
+ err = wks_get_key (&key, fingerprint, addrspec, 1);
+ if (err)
+ goto leave;
+ }
+
+ /* Hack to support posteo but let them disable this by setting the
+ * new policy-version flag. */
+ if (policy->protocol_version < 3
+ && !ascii_strcasecmp (domain, "posteo.de"))
+ {
+ log_info ("Warning: Using draft-1 method for domain '%s'\n", domain);
+ no_encrypt = 1;
+ posteo_hack = 1;
+ }
+
+ /* Encrypt the key part. */
+ if (!no_encrypt)
+ {
+ es_rewind (key);
+ err = encrypt_response (&keyenc, key, submission_to, fingerprint);
+ if (err)
+ goto leave;
+ es_fclose (key);
+ key = NULL;
+ }
+
+ /* Send the key. */
+ err = mime_maker_new (&mime, NULL);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "From", addrspec);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "To", submission_to);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "Subject", "Key publishing request");
+ if (err)
+ goto leave;
+
+ /* Tell server which draft we support. */
+ err = mime_maker_add_header (mime, "Wks-Draft-Version",
+ STR2(WKS_DRAFT_VERSION));
+ if (err)
+ goto leave;
+
+ if (no_encrypt)
+ {
+ void *data;
+ size_t datalen, n;
+
+ if (posteo_hack)
+ {
+ /* Needs a multipart/mixed with one(!) attachment. It does
+ * not grok a non-multipart mail. */
+ err = mime_maker_add_header (mime, "Content-Type", "multipart/mixed");
+ if (err)
+ goto leave;
+ err = mime_maker_add_container (mime);
+ if (err)
+ goto leave;
+ }
+
+ err = mime_maker_add_header (mime, "Content-type",
+ "application/pgp-keys");
+ if (err)
+ goto leave;
+
+ if (es_fclose_snatch (key, &data, &datalen))
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ key = NULL;
+ /* We need to skip over the first line which has a content-type
+ * header not needed here. */
+ for (n=0; n < datalen ; n++)
+ if (((const char *)data)[n] == '\n')
+ {
+ n++;
+ break;
+ }
+
+ err = mime_maker_add_body_data (mime, (char*)data + n, datalen - n);
+ xfree (data);
+ if (err)
+ goto leave;
+ }
+ else
+ {
+ err = mime_maker_add_header (mime, "Content-Type",
+ "multipart/encrypted; "
+ "protocol=\"application/pgp-encrypted\"");
+ if (err)
+ goto leave;
+ err = mime_maker_add_container (mime);
+ if (err)
+ goto leave;
+
+ err = mime_maker_add_header (mime, "Content-Type",
+ "application/pgp-encrypted");
+ if (err)
+ goto leave;
+ err = mime_maker_add_body (mime, "Version: 1\n");
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "Content-Type",
+ "application/octet-stream");
+ if (err)
+ goto leave;
+
+ err = mime_maker_add_stream (mime, &keyenc);
+ if (err)
+ goto leave;
+ }
+
+ err = wks_send_mime (mime);
+
+ leave:
+ mime_maker_release (mime);
+ xfree (submission_to);
+ free_uidinfo_list (uidlist);
+ es_fclose (keyenc);
+ es_fclose (key);
+ wks_free_policy (policy);
+ xfree (policy);
+ xfree (addrspec);
+ return err;
+}
+
+
+
+static void
+encrypt_response_status_cb (void *opaque, const char *keyword, char *args)
+{
+ gpg_error_t *failure = opaque;
+ char *fields[2];
+
+ if (DBG_CRYPTO)
+ log_debug ("gpg status: %s %s\n", keyword, args);
+
+ if (!strcmp (keyword, "FAILURE"))
+ {
+ if (split_fields (args, fields, DIM (fields)) >= 2
+ && !strcmp (fields[0], "encrypt"))
+ *failure = strtoul (fields[1], NULL, 10);
+ }
+
+}
+
+
+/* Encrypt the INPUT stream to a new stream which is stored at success
+ * at R_OUTPUT. Encryption is done for ADDRSPEC and for FINGERPRINT
+ * (so that the sent message may later be inspected by the user). We
+ * currently retrieve that key from the WKD, DANE, or from "local".
+ * "local" is last to prefer the latest key version but use a local
+ * copy in case we are working offline. It might be useful for the
+ * server to send the fingerprint of its encryption key - or even the
+ * entire key back. */
+static gpg_error_t
+encrypt_response (estream_t *r_output, estream_t input, const char *addrspec,
+ const char *fingerprint)
+{
+ gpg_error_t err;
+ ccparray_t ccp;
+ const char **argv;
+ estream_t output;
+ gpg_error_t gpg_err = 0;
+
+ *r_output = NULL;
+
+ output = es_fopenmem (0, "w+b");
+ if (!output)
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error allocating memory buffer: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ ccparray_init (&ccp, 0);
+
+ ccparray_put (&ccp, "--no-options");
+ if (!opt.verbose)
+ ccparray_put (&ccp, "--quiet");
+ else if (opt.verbose > 1)
+ ccparray_put (&ccp, "--verbose");
+ ccparray_put (&ccp, "--batch");
+ ccparray_put (&ccp, "--status-fd=2");
+ ccparray_put (&ccp, "--always-trust");
+ ccparray_put (&ccp, "--armor");
+ ccparray_put (&ccp, "-z0"); /* No compression for improved robustness. */
+ if (fake_submission_addr)
+ ccparray_put (&ccp, "--auto-key-locate=clear,local");
+ else
+ ccparray_put (&ccp, "--auto-key-locate=clear,wkd,dane,local");
+ ccparray_put (&ccp, "--recipient");
+ ccparray_put (&ccp, addrspec);
+ ccparray_put (&ccp, "--recipient");
+ ccparray_put (&ccp, fingerprint);
+ ccparray_put (&ccp, "--encrypt");
+ ccparray_put (&ccp, "--");
+
+ ccparray_put (&ccp, NULL);
+ argv = ccparray_get (&ccp, NULL);
+ if (!argv)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+ err = gnupg_exec_tool_stream (opt.gpg_program, argv, input,
+ NULL, output,
+ encrypt_response_status_cb, &gpg_err);
+ if (err)
+ {
+ if (gpg_err)
+ err = gpg_err;
+ log_error ("encryption failed: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+
+ es_rewind (output);
+ *r_output = output;
+ output = NULL;
+
+ leave:
+ es_fclose (output);
+ xfree (argv);
+ return err;
+}
+
+
+static gpg_error_t
+send_confirmation_response (const char *sender, const char *address,
+ const char *nonce, int encrypt,
+ const char *fingerprint)
+{
+ gpg_error_t err;
+ estream_t body = NULL;
+ estream_t bodyenc = NULL;
+ mime_maker_t mime = NULL;
+
+ body = es_fopenmem (0, "w+b");
+ if (!body)
+ {
+ err = gpg_error_from_syserror ();
+ log_error ("error allocating memory buffer: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ /* It is fine to use 8 bit encoding because that is encrypted and
+ * only our client will see it. */
+ if (encrypt)
+ {
+ es_fputs ("Content-Type: application/vnd.gnupg.wks\n"
+ "Content-Transfer-Encoding: 8bit\n"
+ "\n",
+ body);
+ }
+
+ es_fprintf (body, ("type: confirmation-response\n"
+ "sender: %s\n"
+ "address: %s\n"
+ "nonce: %s\n"),
+ sender,
+ address,
+ nonce);
+
+ es_rewind (body);
+ if (encrypt)
+ {
+ err = encrypt_response (&bodyenc, body, sender, fingerprint);
+ if (err)
+ goto leave;
+ es_fclose (body);
+ body = NULL;
+ }
+
+ err = mime_maker_new (&mime, NULL);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "From", address);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "To", sender);
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "Subject", "Key publication confirmation");
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "Wks-Draft-Version",
+ STR2(WKS_DRAFT_VERSION));
+ if (err)
+ goto leave;
+
+ if (encrypt)
+ {
+ err = mime_maker_add_header (mime, "Content-Type",
+ "multipart/encrypted; "
+ "protocol=\"application/pgp-encrypted\"");
+ if (err)
+ goto leave;
+ err = mime_maker_add_container (mime);
+ if (err)
+ goto leave;
+
+ err = mime_maker_add_header (mime, "Content-Type",
+ "application/pgp-encrypted");
+ if (err)
+ goto leave;
+ err = mime_maker_add_body (mime, "Version: 1\n");
+ if (err)
+ goto leave;
+ err = mime_maker_add_header (mime, "Content-Type",
+ "application/octet-stream");
+ if (err)
+ goto leave;
+
+ err = mime_maker_add_stream (mime, &bodyenc);
+ if (err)
+ goto leave;
+ }
+ else
+ {
+ err = mime_maker_add_header (mime, "Content-Type",
+ "application/vnd.gnupg.wks");
+ if (err)
+ goto leave;
+ err = mime_maker_add_stream (mime, &body);
+ if (err)
+ goto leave;
+ }
+
+ err = wks_send_mime (mime);
+
+ leave:
+ mime_maker_release (mime);
+ es_fclose (bodyenc);
+ es_fclose (body);
+ return err;
+}
+
+
+/* Reply to a confirmation request. The MSG has already been
+ * decrypted and we only need to send the nonce back. MAINFPR is
+ * either NULL or the primary key fingerprint of the key used to
+ * decrypt the request. */
+static gpg_error_t
+process_confirmation_request (estream_t msg, const char *mainfpr)
+{
+ gpg_error_t err;
+ nvc_t nvc;
+ nve_t item;
+ const char *value, *sender, *address, *fingerprint, *nonce;
+
+ err = nvc_parse (&nvc, NULL, msg);
+ if (err)
+ {
+ log_error ("parsing the WKS message failed: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+
+ if (DBG_MIME)
+ {
+ log_debug ("request follows:\n");
+ nvc_write (nvc, log_get_stream ());
+ }
+
+ /* Check that this is a confirmation request. */
+ if (!((item = nvc_lookup (nvc, "type:")) && (value = nve_value (item))
+ && !strcmp (value, "confirmation-request")))
+ {
+ if (item && value)
+ log_error ("received unexpected wks message '%s'\n", value);
+ else
+ log_error ("received invalid wks message: %s\n", "'type' missing");
+ err = gpg_error (GPG_ERR_UNEXPECTED_MSG);
+ goto leave;
+ }
+
+ /* Get the fingerprint. */
+ if (!((item = nvc_lookup (nvc, "fingerprint:"))
+ && (value = nve_value (item))
+ && strlen (value) >= 40))
+ {
+ log_error ("received invalid wks message: %s\n",
+ "'fingerprint' missing or invalid");
+ err = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+ fingerprint = value;
+
+ /* Check that the fingerprint matches the key used to decrypt the
+ * message. In --read mode or with the old format we don't have the
+ * decryption key; thus we can't bail out. */
+ if (!mainfpr || ascii_strcasecmp (mainfpr, fingerprint))
+ {
+ log_info ("target fingerprint: %s\n", fingerprint);
+ log_info ("but decrypted with: %s\n", mainfpr);
+ log_error ("confirmation request not decrypted with target key\n");
+ if (mainfpr)
+ {
+ err = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+ }
+
+ /* Get the address. */
+ if (!((item = nvc_lookup (nvc, "address:")) && (value = nve_value (item))
+ && is_valid_mailbox (value)))
+ {
+ log_error ("received invalid wks message: %s\n",
+ "'address' missing or invalid");
+ err = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+ address = value;
+ /* FIXME: Check that the "address" matches the User ID we want to
+ * publish. */
+
+ /* Get the sender. */
+ if (!((item = nvc_lookup (nvc, "sender:")) && (value = nve_value (item))
+ && is_valid_mailbox (value)))
+ {
+ log_error ("received invalid wks message: %s\n",
+ "'sender' missing or invalid");
+ err = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+ sender = value;
+ /* FIXME: Check that the "sender" matches the From: address. */
+
+ /* Get the nonce. */
+ if (!((item = nvc_lookup (nvc, "nonce:")) && (value = nve_value (item))
+ && strlen (value) > 16))
+ {
+ log_error ("received invalid wks message: %s\n",
+ "'nonce' missing or too short");
+ err = gpg_error (GPG_ERR_INV_DATA);
+ goto leave;
+ }
+ nonce = value;
+
+ /* Send the confirmation. If no key was found, try again without
+ * encryption. */
+ err = send_confirmation_response (sender, address, nonce, 1, fingerprint);
+ if (gpg_err_code (err) == GPG_ERR_NO_PUBKEY)
+ {
+ log_info ("no encryption key found - sending response in the clear\n");
+ err = send_confirmation_response (sender, address, nonce, 0, NULL);
+ }
+
+ leave:
+ nvc_release (nvc);
+ return err;
+}
+
+
+/* Read a confirmation request and decrypt it if needed. This
+ * function may not be used with a mail or MIME message but only with
+ * the actual encrypted or plaintext WKS data. */
+static gpg_error_t
+read_confirmation_request (estream_t msg)
+{
+ gpg_error_t err;
+ int c;
+ estream_t plaintext = NULL;
+
+ /* We take a really simple approach to check whether MSG is
+ * encrypted: We know that an encrypted message is always armored
+ * and thus starts with a few dashes. It is even sufficient to
+ * check for a single dash, because that can never be a proper first
+ * WKS data octet. We need to skip leading spaces, though. */
+ while ((c = es_fgetc (msg)) == ' ' || c == '\t' || c == '\r' || c == '\n')
+ ;
+ if (c == EOF)
+ {
+ log_error ("can't process an empty message\n");
+ return gpg_error (GPG_ERR_INV_DATA);
+ }
+ if (es_ungetc (c, msg) != c)
+ {
+ log_error ("error ungetting octet from message\n");
+ return gpg_error (GPG_ERR_INTERNAL);
+ }
+
+ if (c != '-')
+ err = process_confirmation_request (msg, NULL);
+ else
+ {
+ struct decrypt_stream_parm_s decinfo;
+
+ err = decrypt_stream (&plaintext, &decinfo, msg);
+ if (err)
+ log_error ("decryption failed: %s\n", gpg_strerror (err));
+ else if (decinfo.otrust != 'u')
+ {
+ err = gpg_error (GPG_ERR_WRONG_SECKEY);
+ log_error ("key used to decrypt the confirmation request"
+ " was not generated by us\n");
+ }
+ else
+ err = process_confirmation_request (plaintext, decinfo.mainfpr);
+ xfree (decinfo.fpr);
+ xfree (decinfo.mainfpr);
+ }
+
+ es_fclose (plaintext);
+ return err;
+}
+
+
+/* Called from the MIME receiver to process the plain text data in MSG. */
+static gpg_error_t
+command_receive_cb (void *opaque, const char *mediatype,
+ estream_t msg, unsigned int flags)
+{
+ gpg_error_t err;
+
+ (void)opaque;
+ (void)flags;
+
+ if (!strcmp (mediatype, "application/vnd.gnupg.wks"))
+ err = read_confirmation_request (msg);
+ else
+ {
+ log_info ("ignoring unexpected message of type '%s'\n", mediatype);
+ err = gpg_error (GPG_ERR_UNEXPECTED_MSG);
+ }
+
+ return err;
+}