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-rw-r--r--common/asshelp.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/common/asshelp.c b/common/asshelp.c
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index 0000000..d87017e
--- /dev/null
+++ b/common/asshelp.c
@@ -0,0 +1,685 @@
+/* asshelp.c - Helper functions for Assuan
+ * Copyright (C) 2002, 2004, 2007, 2009, 2010 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of either
+ *
+ * - the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * or
+ *
+ * - the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * or both in parallel, as here.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#ifdef HAVE_LOCALE_H
+#include <locale.h>
+#endif
+
+#include "i18n.h"
+#include "util.h"
+#include "exechelp.h"
+#include "sysutils.h"
+#include "status.h"
+#include "membuf.h"
+#include "asshelp.h"
+
+/* The type we use for lock_agent_spawning. */
+#ifdef HAVE_W32_SYSTEM
+# define lock_spawn_t HANDLE
+#else
+# define lock_spawn_t dotlock_t
+#endif
+
+/* The time we wait until the agent or the dirmngr are ready for
+ operation after we started them before giving up. */
+#ifdef HAVE_W32CE_SYSTEM
+# define SECS_TO_WAIT_FOR_AGENT 30
+# define SECS_TO_WAIT_FOR_DIRMNGR 30
+#else
+# define SECS_TO_WAIT_FOR_AGENT 5
+# define SECS_TO_WAIT_FOR_DIRMNGR 5
+#endif
+
+/* A bitfield that specifies the assuan categories to log. This is
+ identical to the default log handler of libassuan. We need to do
+ it ourselves because we use a custom log handler and want to use
+ the same assuan variables to select the categories to log. */
+static int log_cats;
+#define TEST_LOG_CAT(x) (!! (log_cats & (1 << (x - 1))))
+
+/* The assuan log monitor used to temporary inhibit log messages from
+ * assuan. */
+static int (*my_log_monitor) (assuan_context_t ctx,
+ unsigned int cat,
+ const char *msg);
+
+
+static int
+my_libassuan_log_handler (assuan_context_t ctx, void *hook,
+ unsigned int cat, const char *msg)
+{
+ unsigned int dbgval;
+
+ if (! TEST_LOG_CAT (cat))
+ return 0;
+
+ dbgval = hook? *(unsigned int*)hook : 0;
+ if (!(dbgval & 1024))
+ return 0; /* Assuan debugging is not enabled. */
+
+ if (ctx && my_log_monitor && !my_log_monitor (ctx, cat, msg))
+ return 0; /* Temporary disabled. */
+
+ if (msg)
+ log_string (GPGRT_LOG_DEBUG, msg);
+
+ return 1;
+}
+
+
+/* Setup libassuan to use our own logging functions. Should be used
+ early at startup. */
+void
+setup_libassuan_logging (unsigned int *debug_var_address,
+ int (*log_monitor)(assuan_context_t ctx,
+ unsigned int cat,
+ const char *msg))
+{
+ char *flagstr;
+
+ flagstr = getenv ("ASSUAN_DEBUG");
+ if (flagstr)
+ log_cats = atoi (flagstr);
+ else /* Default to log the control channel. */
+ log_cats = (1 << (ASSUAN_LOG_CONTROL - 1));
+ my_log_monitor = log_monitor;
+ assuan_set_log_cb (my_libassuan_log_handler, debug_var_address);
+}
+
+
+/* Change the Libassuan log categories to those given by NEWCATS.
+ NEWCATS is 0 the default category of ASSUAN_LOG_CONTROL is
+ selected. Note, that setup_libassuan_logging overrides the values
+ given here. */
+void
+set_libassuan_log_cats (unsigned int newcats)
+{
+ if (newcats)
+ log_cats = newcats;
+ else /* Default to log the control channel. */
+ log_cats = (1 << (ASSUAN_LOG_CONTROL - 1));
+}
+
+
+
+static gpg_error_t
+send_one_option (assuan_context_t ctx, gpg_err_source_t errsource,
+ const char *name, const char *value, int use_putenv)
+{
+ gpg_error_t err;
+ char *optstr;
+
+ (void)errsource;
+
+ if (!value || !*value)
+ err = 0; /* Avoid sending empty strings. */
+ else if (asprintf (&optstr, "OPTION %s%s=%s",
+ use_putenv? "putenv=":"", name, value) < 0)
+ err = gpg_error_from_syserror ();
+ else
+ {
+ err = assuan_transact (ctx, optstr, NULL, NULL, NULL, NULL, NULL, NULL);
+ xfree (optstr);
+ }
+
+ return err;
+}
+
+
+/* Send the assuan commands pertaining to the pinentry environment. The
+ OPT_* arguments are optional and may be used to override the
+ defaults taken from the current locale. */
+gpg_error_t
+send_pinentry_environment (assuan_context_t ctx,
+ gpg_err_source_t errsource,
+ const char *opt_lc_ctype,
+ const char *opt_lc_messages,
+ session_env_t session_env)
+
+{
+ gpg_error_t err = 0;
+#if defined(HAVE_SETLOCALE)
+ char *old_lc = NULL;
+#endif
+ char *dft_lc = NULL;
+ const char *dft_ttyname;
+ int iterator;
+ const char *name, *assname, *value;
+ int is_default;
+
+ iterator = 0;
+ while ((name = session_env_list_stdenvnames (&iterator, &assname)))
+ {
+ value = session_env_getenv_or_default (session_env, name, NULL);
+ if (!value)
+ continue;
+
+ if (assname)
+ err = send_one_option (ctx, errsource, assname, value, 0);
+ else
+ {
+ err = send_one_option (ctx, errsource, name, value, 1);
+ if (gpg_err_code (err) == GPG_ERR_UNKNOWN_OPTION)
+ err = 0; /* Server too old; can't pass the new envvars. */
+ }
+ if (err)
+ return err;
+ }
+
+
+ dft_ttyname = session_env_getenv_or_default (session_env, "GPG_TTY",
+ &is_default);
+ if (dft_ttyname && !is_default)
+ dft_ttyname = NULL; /* We need the default value. */
+
+ /* Send the value for LC_CTYPE. */
+#if defined(HAVE_SETLOCALE) && defined(LC_CTYPE)
+ old_lc = setlocale (LC_CTYPE, NULL);
+ if (old_lc)
+ {
+ old_lc = xtrystrdup (old_lc);
+ if (!old_lc)
+ return gpg_error_from_syserror ();
+ }
+ dft_lc = setlocale (LC_CTYPE, "");
+#endif
+ if (opt_lc_ctype || (dft_ttyname && dft_lc))
+ {
+ err = send_one_option (ctx, errsource, "lc-ctype",
+ opt_lc_ctype ? opt_lc_ctype : dft_lc, 0);
+ }
+#if defined(HAVE_SETLOCALE) && defined(LC_CTYPE)
+ if (old_lc)
+ {
+ setlocale (LC_CTYPE, old_lc);
+ xfree (old_lc);
+ }
+#endif
+ if (err)
+ return err;
+
+ /* Send the value for LC_MESSAGES. */
+#if defined(HAVE_SETLOCALE) && defined(LC_MESSAGES)
+ old_lc = setlocale (LC_MESSAGES, NULL);
+ if (old_lc)
+ {
+ old_lc = xtrystrdup (old_lc);
+ if (!old_lc)
+ return gpg_error_from_syserror ();
+ }
+ dft_lc = setlocale (LC_MESSAGES, "");
+#endif
+ if (opt_lc_messages || (dft_ttyname && dft_lc))
+ {
+ err = send_one_option (ctx, errsource, "lc-messages",
+ opt_lc_messages ? opt_lc_messages : dft_lc, 0);
+ }
+#if defined(HAVE_SETLOCALE) && defined(LC_MESSAGES)
+ if (old_lc)
+ {
+ setlocale (LC_MESSAGES, old_lc);
+ xfree (old_lc);
+ }
+#endif
+ if (err)
+ return err;
+
+ return 0;
+}
+
+
+/* Lock a spawning process. The caller needs to provide the address
+ of a variable to store the lock information and the name or the
+ process. */
+static gpg_error_t
+lock_spawning (lock_spawn_t *lock, const char *homedir, const char *name,
+ int verbose)
+{
+ char *fname;
+ (void)verbose;
+
+ *lock = NULL;
+
+ fname = make_absfilename_try
+ (homedir,
+ !strcmp (name, "agent")? "gnupg_spawn_agent_sentinel":
+ !strcmp (name, "dirmngr")? "gnupg_spawn_dirmngr_sentinel":
+ /* */ "gnupg_spawn_unknown_sentinel",
+ NULL);
+ if (!fname)
+ return gpg_error_from_syserror ();
+
+ *lock = dotlock_create (fname, 0);
+ xfree (fname);
+ if (!*lock)
+ return gpg_error_from_syserror ();
+
+ /* FIXME: We should use a timeout of 5000 here - however
+ make_dotlock does not yet support values other than -1 and 0. */
+ if (dotlock_take (*lock, -1))
+ return gpg_error_from_syserror ();
+
+ return 0;
+}
+
+
+/* Unlock the spawning process. */
+static void
+unlock_spawning (lock_spawn_t *lock, const char *name)
+{
+ if (*lock)
+ {
+ (void)name;
+ dotlock_destroy (*lock);
+ *lock = NULL;
+ }
+}
+
+static gpg_error_t
+wait_for_sock (int secs, const char *name, const char *sockname, int verbose, assuan_context_t ctx, int *did_success_msg)
+{
+ gpg_error_t err = 0;
+ int target_us = secs * 1000000;
+ int elapsed_us = 0;
+ /*
+ * 977us * 1024 = just a little more than 1s.
+ * so we will double this timeout 10 times in the first
+ * second, and then switch over to 1s checkins.
+ */
+ int next_sleep_us = 977;
+ int lastalert = secs+1;
+ int secsleft;
+
+ while (elapsed_us < target_us)
+ {
+ if (verbose)
+ {
+ secsleft = (target_us - elapsed_us + 999999)/1000000;
+ /* log_clock ("left=%d last=%d targ=%d elap=%d next=%d\n", */
+ /* secsleft, lastalert, target_us, elapsed_us, */
+ /* next_sleep_us); */
+ if (secsleft < lastalert)
+ {
+ log_info (_("waiting for the %s to come up ... (%ds)\n"),
+ name, secsleft);
+ lastalert = secsleft;
+ }
+ }
+ gnupg_usleep (next_sleep_us);
+ elapsed_us += next_sleep_us;
+ err = assuan_socket_connect (ctx, sockname, 0, 0);
+ if (!err)
+ {
+ if (verbose)
+ {
+ log_info (_("connection to %s established\n"),
+ name);
+ *did_success_msg = 1;
+ }
+ break;
+ }
+ next_sleep_us *= 2;
+ if (next_sleep_us > 1000000)
+ next_sleep_us = 1000000;
+ }
+ return err;
+}
+
+/* Try to connect to the agent via socket or start it if it is not
+ running and AUTOSTART is set. Handle the server's initial
+ greeting. Returns a new assuan context at R_CTX or an error
+ code. */
+gpg_error_t
+start_new_gpg_agent (assuan_context_t *r_ctx,
+ gpg_err_source_t errsource,
+ const char *agent_program,
+ const char *opt_lc_ctype,
+ const char *opt_lc_messages,
+ session_env_t session_env,
+ int autostart, int verbose, int debug,
+ gpg_error_t (*status_cb)(ctrl_t, int, ...),
+ ctrl_t status_cb_arg)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ int did_success_msg = 0;
+ char *sockname;
+ const char *argv[6];
+
+ *r_ctx = NULL;
+
+ err = assuan_new (&ctx);
+ if (err)
+ {
+ log_error ("error allocating assuan context: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ sockname = make_filename_try (gnupg_socketdir (), GPG_AGENT_SOCK_NAME, NULL);
+ if (!sockname)
+ {
+ err = gpg_err_make (errsource, gpg_err_code_from_syserror ());
+ assuan_release (ctx);
+ return err;
+ }
+
+ err = assuan_socket_connect (ctx, sockname, 0, 0);
+ if (err && autostart)
+ {
+ char *abs_homedir;
+ lock_spawn_t lock;
+ char *program = NULL;
+ const char *program_arg = NULL;
+ char *p;
+ const char *s;
+ int i;
+
+ /* With no success start a new server. */
+ if (!agent_program || !*agent_program)
+ agent_program = gnupg_module_name (GNUPG_MODULE_NAME_AGENT);
+ else if ((s=strchr (agent_program, '|')) && s[1] == '-' && s[2]=='-')
+ {
+ /* Hack to insert an additional option on the command line. */
+ program = xtrystrdup (agent_program);
+ if (!program)
+ {
+ gpg_error_t tmperr = gpg_err_make (errsource,
+ gpg_err_code_from_syserror ());
+ xfree (sockname);
+ assuan_release (ctx);
+ return tmperr;
+ }
+ p = strchr (program, '|');
+ *p++ = 0;
+ program_arg = p;
+ }
+
+ if (verbose)
+ log_info (_("no running gpg-agent - starting '%s'\n"),
+ agent_program);
+
+ if (status_cb)
+ status_cb (status_cb_arg, STATUS_PROGRESS,
+ "starting_agent ? 0 0", NULL);
+
+ /* We better pass an absolute home directory to the agent just
+ in case gpg-agent does not convert the passed name to an
+ absolute one (which it should do). */
+ abs_homedir = make_absfilename_try (gnupg_homedir (), NULL);
+ if (!abs_homedir)
+ {
+ gpg_error_t tmperr = gpg_err_make (errsource,
+ gpg_err_code_from_syserror ());
+ log_error ("error building filename: %s\n",gpg_strerror (tmperr));
+ xfree (sockname);
+ assuan_release (ctx);
+ xfree (program);
+ return tmperr;
+ }
+
+ if (fflush (NULL))
+ {
+ gpg_error_t tmperr = gpg_err_make (errsource,
+ gpg_err_code_from_syserror ());
+ log_error ("error flushing pending output: %s\n",
+ strerror (errno));
+ xfree (sockname);
+ assuan_release (ctx);
+ xfree (abs_homedir);
+ xfree (program);
+ return tmperr;
+ }
+
+ /* If the agent has been configured for use with a standard
+ socket, an environment variable is not required and thus
+ we can safely start the agent here. */
+ i = 0;
+ argv[i++] = "--homedir";
+ argv[i++] = abs_homedir;
+ argv[i++] = "--use-standard-socket";
+ if (program_arg)
+ argv[i++] = program_arg;
+ argv[i++] = "--daemon";
+ argv[i++] = NULL;
+
+ if (!(err = lock_spawning (&lock, gnupg_homedir (), "agent", verbose))
+ && assuan_socket_connect (ctx, sockname, 0, 0))
+ {
+ err = gnupg_spawn_process_detached (program? program : agent_program,
+ argv, NULL);
+ if (err)
+ log_error ("failed to start agent '%s': %s\n",
+ agent_program, gpg_strerror (err));
+ else
+ err = wait_for_sock (SECS_TO_WAIT_FOR_AGENT, "agent",
+ sockname, verbose, ctx, &did_success_msg);
+ }
+
+ unlock_spawning (&lock, "agent");
+ xfree (abs_homedir);
+ xfree (program);
+ }
+ xfree (sockname);
+ if (err)
+ {
+ if (autostart || gpg_err_code (err) != GPG_ERR_ASS_CONNECT_FAILED)
+ log_error ("can't connect to the agent: %s\n", gpg_strerror (err));
+ assuan_release (ctx);
+ return gpg_err_make (errsource, GPG_ERR_NO_AGENT);
+ }
+
+ if (debug && !did_success_msg)
+ log_debug ("connection to agent established\n");
+
+ err = assuan_transact (ctx, "RESET",
+ NULL, NULL, NULL, NULL, NULL, NULL);
+ if (!err)
+ {
+ err = send_pinentry_environment (ctx, errsource,
+ opt_lc_ctype, opt_lc_messages,
+ session_env);
+ if (gpg_err_code (err) == GPG_ERR_FORBIDDEN
+ && gpg_err_source (err) == GPG_ERR_SOURCE_GPGAGENT)
+ {
+ /* Check whether we are in restricted mode. */
+ if (!assuan_transact (ctx, "GETINFO restricted",
+ NULL, NULL, NULL, NULL, NULL, NULL))
+ {
+ if (verbose)
+ log_info (_("connection to agent is in restricted mode\n"));
+ err = 0;
+ }
+ }
+ }
+ if (err)
+ {
+ assuan_release (ctx);
+ return err;
+ }
+
+ *r_ctx = ctx;
+ return 0;
+}
+
+
+/* Try to connect to the dirmngr via a socket. On platforms
+ supporting it, start it up if needed and if AUTOSTART is true.
+ Returns a new assuan context at R_CTX or an error code. */
+gpg_error_t
+start_new_dirmngr (assuan_context_t *r_ctx,
+ gpg_err_source_t errsource,
+ const char *dirmngr_program,
+ int autostart,
+ int verbose, int debug,
+ gpg_error_t (*status_cb)(ctrl_t, int, ...),
+ ctrl_t status_cb_arg)
+{
+ gpg_error_t err;
+ assuan_context_t ctx;
+ const char *sockname;
+ int did_success_msg = 0;
+
+ *r_ctx = NULL;
+
+ err = assuan_new (&ctx);
+ if (err)
+ {
+ log_error ("error allocating assuan context: %s\n", gpg_strerror (err));
+ return err;
+ }
+
+ sockname = dirmngr_socket_name ();
+ err = assuan_socket_connect (ctx, sockname, 0, 0);
+
+#ifdef USE_DIRMNGR_AUTO_START
+ if (err && autostart)
+ {
+ lock_spawn_t lock;
+ const char *argv[4];
+ char *abs_homedir;
+
+ /* No connection: Try start a new Dirmngr. */
+ if (!dirmngr_program || !*dirmngr_program)
+ dirmngr_program = gnupg_module_name (GNUPG_MODULE_NAME_DIRMNGR);
+
+ if (verbose)
+ log_info (_("no running Dirmngr - starting '%s'\n"),
+ dirmngr_program);
+
+ if (status_cb)
+ status_cb (status_cb_arg, STATUS_PROGRESS,
+ "starting_dirmngr ? 0 0", NULL);
+
+ abs_homedir = make_absfilename (gnupg_homedir (), NULL);
+ if (!abs_homedir)
+ {
+ gpg_error_t tmperr = gpg_err_make (errsource,
+ gpg_err_code_from_syserror ());
+ log_error ("error building filename: %s\n",gpg_strerror (tmperr));
+ assuan_release (ctx);
+ return tmperr;
+ }
+
+ if (fflush (NULL))
+ {
+ gpg_error_t tmperr = gpg_err_make (errsource,
+ gpg_err_code_from_syserror ());
+ log_error ("error flushing pending output: %s\n",
+ strerror (errno));
+ assuan_release (ctx);
+ return tmperr;
+ }
+
+ argv[0] = "--daemon";
+ /* Try starting the daemon. Versions of dirmngr < 2.1.15 do
+ * this only if the home directory is given on the command line. */
+ argv[1] = "--homedir";
+ argv[2] = abs_homedir;
+ argv[3] = NULL;
+
+ if (!(err = lock_spawning (&lock, gnupg_homedir (), "dirmngr", verbose))
+ && assuan_socket_connect (ctx, sockname, 0, 0))
+ {
+ err = gnupg_spawn_process_detached (dirmngr_program, argv, NULL);
+ if (err)
+ log_error ("failed to start the dirmngr '%s': %s\n",
+ dirmngr_program, gpg_strerror (err));
+ else
+ err = wait_for_sock (SECS_TO_WAIT_FOR_DIRMNGR, "dirmngr",
+ sockname, verbose, ctx, &did_success_msg);
+ }
+
+ unlock_spawning (&lock, "dirmngr");
+ xfree (abs_homedir);
+ }
+#else
+ (void)dirmngr_program;
+ (void)verbose;
+ (void)status_cb;
+ (void)status_cb_arg;
+#endif /*USE_DIRMNGR_AUTO_START*/
+
+ if (err)
+ {
+ if (autostart || gpg_err_code (err) != GPG_ERR_ASS_CONNECT_FAILED)
+ log_error ("connecting dirmngr at '%s' failed: %s\n",
+ sockname, gpg_strerror (err));
+ assuan_release (ctx);
+ return gpg_err_make (errsource, GPG_ERR_NO_DIRMNGR);
+ }
+
+ if (debug && !did_success_msg)
+ log_debug ("connection to the dirmngr established\n");
+
+ *r_ctx = ctx;
+ return 0;
+}
+
+
+/* Return the version of a server using "GETINFO version". On success
+ 0 is returned and R_VERSION receives a malloced string with the
+ version which must be freed by the caller. On error NULL is stored
+ at R_VERSION and an error code returned. Mode is in general 0 but
+ certain values may be used to modify the used version command:
+
+ MODE == 0 = Use "GETINFO version"
+ MODE == 2 - Use "SCD GETINFO version"
+ */
+gpg_error_t
+get_assuan_server_version (assuan_context_t ctx, int mode, char **r_version)
+{
+ gpg_error_t err;
+ membuf_t data;
+
+ init_membuf (&data, 64);
+ err = assuan_transact (ctx,
+ mode == 2? "SCD GETINFO version"
+ /**/ : "GETINFO version",
+ put_membuf_cb, &data,
+ NULL, NULL, NULL, NULL);
+ if (err)
+ {
+ xfree (get_membuf (&data, NULL));
+ *r_version = NULL;
+ }
+ else
+ {
+ put_membuf (&data, "", 1);
+ *r_version = get_membuf (&data, NULL);
+ if (!*r_version)
+ err = gpg_error_from_syserror ();
+ }
+ return err;
+}