/* Try to connect to the agent via socket or fork it off and work by
pipes. 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 *homedir,
const char *agent_program,
const char *opt_lc_ctype,
const char *opt_lc_messages,
session_env_t session_env,
int verbose, int debug,
gpg_error_t (*status_cb)(ctrl_t, int, ...),
ctrl_t status_cb_arg)
{
/* If we ever failed to connect via a socket we will force the use
of the pipe based server for the lifetime of the process. */
static int force_pipe_server = 0;
gpg_error_t err = 0;
char *infostr, *p;
assuan_context_t ctx;
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;
}
restart:
infostr = force_pipe_server? NULL : getenv ("GPG_AGENT_INFO");
if (!infostr || !*infostr)
{
char *sockname;
const char *argv[3];
pid_t pid;
int excode;
/* First check whether we can connect at the standard
socket. */
sockname = make_filename (homedir, "S.gpg-agent", NULL);
err = assuan_socket_connect (ctx, sockname, 0, 0);
if (err)
{
/* With no success start a new server. */
if (!agent_program || !*agent_program)
agent_program = gnupg_module_name (GNUPG_MODULE_NAME_AGENT);
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);
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);
return tmperr;
}
argv[0] = "--use-standard-socket-p";
argv[1] = NULL;
err = gnupg_spawn_process_fd (agent_program, argv, -1, -1, -1, &pid);
if (err)
log_debug ("starting '%s' for testing failed: %s\n",
agent_program, gpg_strerror (err));
else if ((err = gnupg_wait_process (agent_program, pid, 1, &excode)))
{
if (excode == -1)
log_debug ("running '%s' for testing failed (wait): %s\n",
agent_program, gpg_strerror (err));
}
gnupg_release_process (pid);
if (!err && !excode)
{
/* If the agent has been configured for use with a
standard socket, an environment variable is not
required and thus we we can savely start the agent
here. */
lock_spawn_t lock;
argv[0] = "--daemon";
argv[1] = "--use-standard-socket";
argv[2] = NULL;
if (!(err = lock_spawning (&lock, homedir, "agent", verbose))
&& assuan_socket_connect (ctx, sockname, 0, 0))
{
err = gnupg_spawn_process_detached (agent_program, argv,NULL);
if (err)
log_error ("failed to start agent '%s': %s\n",
agent_program, gpg_strerror (err));
else
{
int i;
for (i=0; i < SECS_TO_WAIT_FOR_AGENT; i++)
{
if (verbose)
log_info (_("waiting for the agent "
"to come up ... (%ds)\n"),
SECS_TO_WAIT_FOR_AGENT - i);
gnupg_sleep (1);
err = assuan_socket_connect (ctx, sockname, 0, 0);
if (!err)
{
if (verbose)
{
log_info (_("connection to agent "
"established\n"));
did_success_msg = 1;
}
break;
}
}
}
}
unlock_spawning (&lock, "agent");
}
else
{
/* If using the standard socket is not the default we
start the agent as a pipe server which gives us most
of the required features except for passphrase
caching etc. */
const char *pgmname;
int no_close_list[3];
int i;
if ( !(pgmname = strrchr (agent_program, '/')))
pgmname = agent_program;
else
pgmname++;
argv[0] = pgmname;
argv[1] = "--server";
argv[2] = NULL;
i=0;
if (log_get_fd () != -1)
no_close_list[i++] = assuan_fd_from_posix_fd (log_get_fd ());
no_close_list[i++] = assuan_fd_from_posix_fd (fileno (stderr));
no_close_list[i] = -1;
/* Connect to the agent and perform initial handshaking. */
err = assuan_pipe_connect (ctx, agent_program, argv,
no_close_list, NULL, NULL, 0);
}
}
xfree (sockname);
}
else
{
int prot;
int pid;
infostr = xstrdup (infostr);
if ( !(p = strchr (infostr, PATHSEP_C)) || p == infostr)
{
log_error (_("malformed GPG_AGENT_INFO environment variable\n"));
xfree (infostr);
force_pipe_server = 1;
goto restart;
}
*p++ = 0;
pid = atoi (p);
while (*p && *p != PATHSEP_C)
p++;
prot = *p? atoi (p+1) : 0;
if (prot != 1)
{
log_error (_("gpg-agent protocol version %d is not supported\n"),
prot);
xfree (infostr);
force_pipe_server = 1;
goto restart;
}
err = assuan_socket_connect (ctx, infostr, pid, 0);
xfree (infostr);
if (gpg_err_code (err) == GPG_ERR_ASS_CONNECT_FAILED)
{
log_info (_("can't connect to the agent - trying fall back\n"));
force_pipe_server = 1;
goto restart;
}
}
if (err)
{
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 (err)
{
assuan_release (ctx);
return err;
}
*r_ctx = ctx;
return 0;
}
/* Run the encfs tool. */
static gpg_error_t
run_encfs_tool (ctrl_t ctrl, enum encfs_cmds cmd,
const char *rawdir, const char *mountpoint, tupledesc_t tuples,
unsigned int *r_id)
{
gpg_error_t err;
encfs_parm_t parm;
runner_t runner = NULL;
int outbound[2] = { -1, -1 };
int inbound[2] = { -1, -1 };
const char *pgmname;
const char *argv[10];
pid_t pid = (pid_t)(-1);
int idx;
(void)ctrl;
parm = xtrycalloc (1, sizeof *parm);
if (!parm)
{
err = gpg_error_from_syserror ();
goto leave;
}
parm->cmd = cmd;
parm->tuples = ref_tupledesc (tuples);
parm->mountpoint = xtrystrdup (mountpoint);
if (!parm->mountpoint)
{
err = gpg_error_from_syserror ();
goto leave;
}
err = runner_new (&runner, "encfs");
if (err)
goto leave;
err = gnupg_create_inbound_pipe (inbound);
if (!err)
err = gnupg_create_outbound_pipe (outbound);
if (err)
{
log_error (_("error creating a pipe: %s\n"), gpg_strerror (err));
goto leave;
}
pgmname = ENCFS;
idx = 0;
argv[idx++] = "-f";
if (opt.verbose)
argv[idx++] = "-v";
argv[idx++] = "--stdinpass";
argv[idx++] = "--annotate";
argv[idx++] = rawdir;
argv[idx++] = mountpoint;
argv[idx++] = NULL;
assert (idx <= DIM (argv));
err = gnupg_spawn_process_fd (pgmname, argv,
outbound[0], -1, inbound[1], &pid);
if (err)
{
log_error ("error spawning '%s': %s\n", pgmname, gpg_strerror (err));
goto leave;
}
close (outbound[0]); outbound[0] = -1;
close ( inbound[1]); inbound[1] = -1;
runner_set_fds (runner, inbound[0], outbound[1]);
inbound[0] = -1; /* Now owned by RUNNER. */
outbound[1] = -1; /* Now owned by RUNNER. */
runner_set_handler (runner, encfs_handler, encfs_handler_cleanup, parm);
parm = NULL; /* Now owned by RUNNER. */
runner_set_pid (runner, pid);
pid = (pid_t)(-1); /* The process is now owned by RUNNER. */
err = runner_spawn (runner);
if (err)
goto leave;
*r_id = runner_get_rid (runner);
log_info ("running '%s' in the background\n", pgmname);
leave:
if (inbound[0] != -1)
close (inbound[0]);
if (inbound[1] != -1)
close (inbound[1]);
if (outbound[0] != -1)
close (outbound[0]);
if (outbound[1] != -1)
close (outbound[1]);
if (pid != (pid_t)(-1))
{
gnupg_wait_process (pgmname, pid, 1, NULL);
gnupg_release_process (pid);
}
runner_release (runner);
encfs_handler_cleanup (parm);
return err;
}
