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f6728d13e8
* dirmngr/dirmngr.c (main): Avoid calling ldap_wrapper_launch_thread() Before we need it. * dirmngr/ldap-wrapper.c (ldap_wrapper): Call ldap_wrapper_launch_thread() just in time (before any attempt to use an ldap subprocess). -- A dirmngr process that never looks anything up in LDAP has no need for a reaper thread, but one was started automatically. This thread wakes up every two seconds to look for ldap processes that might never have been running. We won't start more than one reaper thread for any given dirmngr due to the static int "done" in ldap_wrapper_launch_thread(), so it's safe to call this every time there is a use of ldap_wrapper. If someone wants to do further dirmngr optimizations for ldap users, the reaper thread itself could use dynamically-calculated timeouts (and probably needs to be alerted dynamically when a new ldap subprocess is available so it can re-calculate those timeouts). Note: It's not clear to me how to test ldap access effectively; i know of no public ldap services that i can verify against, and i do not run my own ldap servers. If someone has a publicly-available ldap server that developers can run tests against, i would be happy to hear about it. Signed-off-by: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
783 lines
22 KiB
C
783 lines
22 KiB
C
/* ldap-wrapper.c - LDAP access via a wrapper process
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* Copyright (C) 2004, 2005, 2007, 2008 g10 Code GmbH
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* Copyright (C) 2010 Free Software Foundation, Inc.
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*
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* This file is part of GnuPG.
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*
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* GnuPG is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* GnuPG is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <https://www.gnu.org/licenses/>.
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*/
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/*
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We can't use LDAP directly for these reasons:
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1. On some systems the LDAP library uses (indirectly) pthreads and
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that is not compatible with PTh.
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2. It is huge library in particular if TLS comes into play. So
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problems with unfreed memory might turn up and we don't want
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this in a long running daemon.
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3. There is no easy way for timeouts. In particular the timeout
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value does not work for DNS lookups (well, this is usual) and it
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seems not to work while loading a large attribute like a
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CRL. Having a separate process allows us to either tell the
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process to commit suicide or have our own housekepping function
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kill it after some time. The latter also allows proper
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cancellation of a query at any point of time.
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4. Given that we are going out to the network and usually get back
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a long response, the fork/exec overhead is acceptable.
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Note that under WindowsCE the number of processes is strongly
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limited (32 processes including the kernel processes) and thus we
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don't use the process approach but implement a different wrapper in
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ldap-wrapper-ce.c.
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*/
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#include <config.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <errno.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <time.h>
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#include <npth.h>
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#include "dirmngr.h"
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#include "exechelp.h"
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#include "misc.h"
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#include "ldap-wrapper.h"
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#ifdef HAVE_W32_SYSTEM
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#define setenv(a,b,c) SetEnvironmentVariable ((a),(b))
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#else
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#define pth_close(fd) close(fd)
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#endif
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#ifndef USE_LDAPWRAPPER
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# error This module is not expected to be build.
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#endif
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/* In case sysconf does not return a value we need to have a limit. */
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#ifdef _POSIX_OPEN_MAX
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#define MAX_OPEN_FDS _POSIX_OPEN_MAX
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#else
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#define MAX_OPEN_FDS 20
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#endif
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#define INACTIVITY_TIMEOUT (opt.ldaptimeout + 60*5) /* seconds */
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#define TIMERTICK_INTERVAL 2
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/* To keep track of the LDAP wrapper state we use this structure. */
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struct wrapper_context_s
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{
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struct wrapper_context_s *next;
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pid_t pid; /* The pid of the wrapper process. */
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int printable_pid; /* Helper to print diagnostics after the process has
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been cleaned up. */
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int fd; /* Connected with stdout of the ldap wrapper. */
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gpg_error_t fd_error; /* Set to the gpg_error of the last read error
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if any. */
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int log_fd; /* Connected with stderr of the ldap wrapper. */
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ctrl_t ctrl; /* Connection data. */
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int ready; /* Internally used to mark to be removed contexts. */
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ksba_reader_t reader; /* The ksba reader object or NULL. */
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char *line; /* Used to print the log lines (malloced). */
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size_t linesize;/* Allocated size of LINE. */
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size_t linelen; /* Use size of LINE. */
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time_t stamp; /* The last time we noticed ativity. */
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};
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/* We keep a global list of spawed wrapper process. A separate thread
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makes use of this list to log error messages and to watch out for
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finished processes. */
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static struct wrapper_context_s *wrapper_list;
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/* We need to know whether we are shutting down the process. */
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static int shutting_down;
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/* Close the pth file descriptor FD and set it to -1. */
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#define SAFE_CLOSE(fd) \
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do { int _fd = fd; if (_fd != -1) { close (_fd); fd = -1;} } while (0)
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/* Read a fixed amount of data from READER into BUFFER. */
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static gpg_error_t
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read_buffer (ksba_reader_t reader, unsigned char *buffer, size_t count)
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{
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gpg_error_t err;
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size_t nread;
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while (count)
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{
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err = ksba_reader_read (reader, buffer, count, &nread);
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if (err)
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return err;
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buffer += nread;
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count -= nread;
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}
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return 0;
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}
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/* Release the wrapper context and kill a running wrapper process. */
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static void
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destroy_wrapper (struct wrapper_context_s *ctx)
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{
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if (ctx->pid != (pid_t)(-1))
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{
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gnupg_kill_process (ctx->pid);
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gnupg_release_process (ctx->pid);
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}
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ksba_reader_release (ctx->reader);
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SAFE_CLOSE (ctx->fd);
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SAFE_CLOSE (ctx->log_fd);
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xfree (ctx->line);
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xfree (ctx);
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}
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/* Print the content of LINE to thye log stream but make sure to only
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print complete lines. Using NULL for LINE will flush any pending
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output. LINE may be modified by this function. */
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static void
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print_log_line (struct wrapper_context_s *ctx, char *line)
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{
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char *s;
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size_t n;
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if (!line)
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{
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if (ctx->line && ctx->linelen)
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{
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log_info ("%s\n", ctx->line);
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ctx->linelen = 0;
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}
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return;
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}
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while ((s = strchr (line, '\n')))
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{
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*s = 0;
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if (ctx->line && ctx->linelen)
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{
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log_info ("%s", ctx->line);
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ctx->linelen = 0;
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log_printf ("%s\n", line);
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}
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else
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log_info ("%s\n", line);
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line = s + 1;
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}
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n = strlen (line);
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if (n)
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{
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if (ctx->linelen + n + 1 >= ctx->linesize)
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{
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char *tmp;
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size_t newsize;
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newsize = ctx->linesize + ((n + 255) & ~255) + 1;
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tmp = (ctx->line ? xtryrealloc (ctx->line, newsize)
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: xtrymalloc (newsize));
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if (!tmp)
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{
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log_error (_("error printing log line: %s\n"), strerror (errno));
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return;
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}
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ctx->line = tmp;
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ctx->linesize = newsize;
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}
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memcpy (ctx->line + ctx->linelen, line, n);
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ctx->linelen += n;
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ctx->line[ctx->linelen] = 0;
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}
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}
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/* Read data from the log stream. Returns true if the log stream
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indicated EOF or error. */
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static int
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read_log_data (struct wrapper_context_s *ctx)
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{
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int n;
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char line[256];
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/* We must use the npth_read function for pipes, always. */
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do
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n = npth_read (ctx->log_fd, line, sizeof line - 1);
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while (n < 0 && errno == EINTR);
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if (n <= 0) /* EOF or error. */
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{
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if (n < 0)
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log_error (_("error reading log from ldap wrapper %d: %s\n"),
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(int)ctx->pid, strerror (errno));
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print_log_line (ctx, NULL);
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SAFE_CLOSE (ctx->log_fd);
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return 1;
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}
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line[n] = 0;
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print_log_line (ctx, line);
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if (ctx->stamp != (time_t)(-1))
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ctx->stamp = time (NULL);
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return 0;
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}
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/* This function is run by a separate thread to maintain the list of
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wrappers and to log error messages from these wrappers. */
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void *
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ldap_wrapper_thread (void *dummy)
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{
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int nfds;
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struct wrapper_context_s *ctx;
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struct wrapper_context_s *ctx_prev;
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struct timespec abstime;
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struct timespec curtime;
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struct timespec timeout;
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fd_set fdset;
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int ret;
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time_t exptime;
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(void)dummy;
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npth_clock_gettime (&abstime);
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abstime.tv_sec += TIMERTICK_INTERVAL;
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for (;;)
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{
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int any_action = 0;
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npth_clock_gettime (&curtime);
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if (!(npth_timercmp (&curtime, &abstime, <)))
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{
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/* Inactivity is checked below. Nothing else to do. */
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npth_clock_gettime (&abstime);
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abstime.tv_sec += TIMERTICK_INTERVAL;
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}
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npth_timersub (&abstime, &curtime, &timeout);
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FD_ZERO (&fdset);
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nfds = -1;
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for (ctx = wrapper_list; ctx; ctx = ctx->next)
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{
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if (ctx->log_fd != -1)
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{
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FD_SET (ctx->log_fd, &fdset);
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if (ctx->log_fd > nfds)
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nfds = ctx->log_fd;
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}
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}
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nfds++;
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/* FIXME: For Windows, we have to use a reader thread on the
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pipe that signals an event (and a npth_select_ev variant). */
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ret = npth_pselect (nfds + 1, &fdset, NULL, NULL, &timeout, NULL);
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if (ret == -1)
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{
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if (errno != EINTR)
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{
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log_error (_("npth_select failed: %s - waiting 1s\n"),
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strerror (errno));
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npth_sleep (1);
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}
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continue;
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}
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/* All timestamps before exptime should be considered expired. */
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exptime = time (NULL);
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if (exptime > INACTIVITY_TIMEOUT)
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exptime -= INACTIVITY_TIMEOUT;
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/* Note that there is no need to lock the list because we always
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add entries at the head (with a pending event status) and
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thus traversing the list will even work if we have a context
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switch in waitpid (which should anyway only happen with Pth's
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hard system call mapping). */
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for (ctx = wrapper_list; ctx; ctx = ctx->next)
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{
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/* Check whether there is any logging to be done. */
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if (nfds && ctx->log_fd != -1 && FD_ISSET (ctx->log_fd, &fdset))
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{
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if (read_log_data (ctx))
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{
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SAFE_CLOSE (ctx->log_fd);
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any_action = 1;
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}
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}
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/* Check whether the process is still running. */
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if (ctx->pid != (pid_t)(-1))
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{
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gpg_error_t err;
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int status;
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err = gnupg_wait_process ("[dirmngr_ldap]", ctx->pid, 0,
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&status);
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if (!err)
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{
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log_info (_("ldap wrapper %d ready"), (int)ctx->pid);
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ctx->ready = 1;
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gnupg_release_process (ctx->pid);
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ctx->pid = (pid_t)(-1);
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any_action = 1;
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}
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else if (gpg_err_code (err) == GPG_ERR_GENERAL)
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{
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if (status == 10)
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log_info (_("ldap wrapper %d ready: timeout\n"),
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(int)ctx->pid);
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else
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log_info (_("ldap wrapper %d ready: exitcode=%d\n"),
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(int)ctx->pid, status);
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ctx->ready = 1;
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gnupg_release_process (ctx->pid);
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ctx->pid = (pid_t)(-1);
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any_action = 1;
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}
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else if (gpg_err_code (err) != GPG_ERR_TIMEOUT)
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{
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log_error (_("waiting for ldap wrapper %d failed: %s\n"),
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(int)ctx->pid, gpg_strerror (err));
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any_action = 1;
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}
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}
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/* Check whether we should terminate the process. */
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if (ctx->pid != (pid_t)(-1)
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&& ctx->stamp != (time_t)(-1) && ctx->stamp < exptime)
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{
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gnupg_kill_process (ctx->pid);
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ctx->stamp = (time_t)(-1);
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log_info (_("ldap wrapper %d stalled - killing\n"),
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(int)ctx->pid);
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/* We need to close the log fd because the cleanup loop
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waits for it. */
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SAFE_CLOSE (ctx->log_fd);
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any_action = 1;
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}
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}
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/* If something has been printed to the log file or we got an
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EOF from a wrapper, we now print the list of active
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wrappers. */
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if (any_action && DBG_LOOKUP)
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{
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log_info ("ldap worker stati:\n");
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for (ctx = wrapper_list; ctx; ctx = ctx->next)
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log_info (" c=%p pid=%d/%d rdr=%p ctrl=%p/%d la=%lu rdy=%d\n",
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ctx,
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(int)ctx->pid, (int)ctx->printable_pid,
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ctx->reader,
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ctx->ctrl, ctx->ctrl? ctx->ctrl->refcount:0,
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(unsigned long)ctx->stamp, ctx->ready);
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}
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/* Use a separate loop to check whether ready marked wrappers
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may be removed. We may only do so if the ksba reader object
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is not anymore in use or we are in shutdown state. */
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again:
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for (ctx_prev=NULL, ctx=wrapper_list; ctx; ctx_prev=ctx, ctx=ctx->next)
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if (ctx->ready
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&& ((ctx->log_fd == -1 && !ctx->reader) || shutting_down))
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{
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if (ctx_prev)
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ctx_prev->next = ctx->next;
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else
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wrapper_list = ctx->next;
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destroy_wrapper (ctx);
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/* We need to restart because destroy_wrapper might have
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done a context switch. */
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goto again;
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}
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}
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/*NOTREACHED*/
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return NULL; /* Make the compiler happy. */
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}
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/* Start the reaper thread for the ldap wrapper. */
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void
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ldap_wrapper_launch_thread (void)
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{
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static int done;
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npth_attr_t tattr;
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npth_t thread;
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int err;
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if (done)
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return;
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done = 1;
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npth_attr_init (&tattr);
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npth_attr_setdetachstate (&tattr, NPTH_CREATE_DETACHED);
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err = npth_create (&thread, &tattr, ldap_wrapper_thread, NULL);
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if (err)
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{
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log_error (_("error spawning ldap wrapper reaper thread: %s\n"),
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strerror (err) );
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dirmngr_exit (1);
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}
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npth_setname_np (thread, "ldap-reaper");
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npth_attr_destroy (&tattr);
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}
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/* Wait until all ldap wrappers have terminated. We assume that the
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kill has already been sent to all of them. */
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void
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ldap_wrapper_wait_connections ()
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{
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shutting_down = 1;
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/* FIXME: This is a busy wait. */
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while (wrapper_list)
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npth_usleep (200);
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}
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/* This function is to be used to release a context associated with the
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given reader object. */
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void
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ldap_wrapper_release_context (ksba_reader_t reader)
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{
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struct wrapper_context_s *ctx;
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if (!reader )
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return;
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for (ctx=wrapper_list; ctx; ctx=ctx->next)
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if (ctx->reader == reader)
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{
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if (DBG_LOOKUP)
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log_info ("releasing ldap worker c=%p pid=%d/%d rdr=%p ctrl=%p/%d\n",
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ctx,
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(int)ctx->pid, (int)ctx->printable_pid,
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ctx->reader,
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ctx->ctrl, ctx->ctrl? ctx->ctrl->refcount:0);
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ctx->reader = NULL;
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SAFE_CLOSE (ctx->fd);
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if (ctx->ctrl)
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{
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ctx->ctrl->refcount--;
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ctx->ctrl = NULL;
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}
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if (ctx->fd_error)
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log_info (_("reading from ldap wrapper %d failed: %s\n"),
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ctx->printable_pid, gpg_strerror (ctx->fd_error));
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break;
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}
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}
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/* Cleanup all resources held by the connection associated with
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CTRL. This is used after a cancel to kill running wrappers. */
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void
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ldap_wrapper_connection_cleanup (ctrl_t ctrl)
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{
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struct wrapper_context_s *ctx;
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for (ctx=wrapper_list; ctx; ctx=ctx->next)
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if (ctx->ctrl && ctx->ctrl == ctrl)
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{
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ctx->ctrl->refcount--;
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ctx->ctrl = NULL;
|
||
if (ctx->pid != (pid_t)(-1))
|
||
gnupg_kill_process (ctx->pid);
|
||
if (ctx->fd_error)
|
||
log_info (_("reading from ldap wrapper %d failed: %s\n"),
|
||
ctx->printable_pid, gpg_strerror (ctx->fd_error));
|
||
}
|
||
}
|
||
|
||
|
||
/* This is the callback used by the ldap wrapper to feed the ksba
|
||
reader with the wrappers stdout. See the description of
|
||
ksba_reader_set_cb for details. */
|
||
static int
|
||
reader_callback (void *cb_value, char *buffer, size_t count, size_t *nread)
|
||
{
|
||
struct wrapper_context_s *ctx = cb_value;
|
||
size_t nleft = count;
|
||
int nfds;
|
||
struct timespec abstime;
|
||
struct timespec curtime;
|
||
struct timespec timeout;
|
||
int saved_errno;
|
||
fd_set fdset, read_fdset;
|
||
int ret;
|
||
|
||
/* FIXME: We might want to add some internal buffering because the
|
||
ksba code does not do any buffering for itself (because a ksba
|
||
reader may be detached from another stream to read other data and
|
||
the it would be cumbersome to get back already buffered
|
||
stuff). */
|
||
|
||
if (!buffer && !count && !nread)
|
||
return -1; /* Rewind is not supported. */
|
||
|
||
/* If we ever encountered a read error, don't continue (we don't want to
|
||
possibly overwrite the last error cause). Bail out also if the
|
||
file descriptor has been closed. */
|
||
if (ctx->fd_error || ctx->fd == -1)
|
||
{
|
||
*nread = 0;
|
||
return -1;
|
||
}
|
||
|
||
FD_ZERO (&fdset);
|
||
FD_SET (ctx->fd, &fdset);
|
||
nfds = ctx->fd + 1;
|
||
|
||
npth_clock_gettime (&abstime);
|
||
abstime.tv_sec += TIMERTICK_INTERVAL;
|
||
|
||
while (nleft > 0)
|
||
{
|
||
int n;
|
||
gpg_error_t err;
|
||
|
||
npth_clock_gettime (&curtime);
|
||
if (!(npth_timercmp (&curtime, &abstime, <)))
|
||
{
|
||
err = dirmngr_tick (ctx->ctrl);
|
||
if (err)
|
||
{
|
||
ctx->fd_error = err;
|
||
SAFE_CLOSE (ctx->fd);
|
||
return -1;
|
||
}
|
||
npth_clock_gettime (&abstime);
|
||
abstime.tv_sec += TIMERTICK_INTERVAL;
|
||
}
|
||
npth_timersub (&abstime, &curtime, &timeout);
|
||
|
||
read_fdset = fdset;
|
||
ret = npth_pselect (nfds, &read_fdset, NULL, NULL, &timeout, NULL);
|
||
saved_errno = errno;
|
||
|
||
if (ret == -1 && saved_errno != EINTR)
|
||
{
|
||
ctx->fd_error = gpg_error_from_errno (errno);
|
||
SAFE_CLOSE (ctx->fd);
|
||
return -1;
|
||
}
|
||
if (ret <= 0)
|
||
/* Timeout. Will be handled when calculating the next timeout. */
|
||
continue;
|
||
|
||
/* This should not block now that select returned with a file
|
||
descriptor. So it shouldn't be necessary to use npth_read
|
||
(and it is slightly dangerous in the sense that a concurrent
|
||
thread might (accidentially?) change the status of ctx->fd
|
||
before we read. FIXME: Set ctx->fd to nonblocking? */
|
||
n = read (ctx->fd, buffer, nleft);
|
||
if (n < 0)
|
||
{
|
||
ctx->fd_error = gpg_error_from_errno (errno);
|
||
SAFE_CLOSE (ctx->fd);
|
||
return -1;
|
||
}
|
||
else if (!n)
|
||
{
|
||
if (nleft == count)
|
||
return -1; /* EOF. */
|
||
break;
|
||
}
|
||
nleft -= n;
|
||
buffer += n;
|
||
if (n > 0 && ctx->stamp != (time_t)(-1))
|
||
ctx->stamp = time (NULL);
|
||
}
|
||
*nread = count - nleft;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Fork and exec the LDAP wrapper and return a new libksba reader
|
||
object at READER. ARGV is a NULL terminated list of arguments for
|
||
the wrapper. The function returns 0 on success or an error code.
|
||
|
||
Special hack to avoid passing a password through the command line
|
||
which is globally visible: If the first element of ARGV is "--pass"
|
||
it will be removed and instead the environment variable
|
||
DIRMNGR_LDAP_PASS will be set to the next value of ARGV. On modern
|
||
OSes the environment is not visible to other users. For those old
|
||
systems where it can't be avoided, we don't want to go into the
|
||
hassle of passing the password via stdin; it's just too complicated
|
||
and an LDAP password used for public directory lookups should not
|
||
be that confidential. */
|
||
gpg_error_t
|
||
ldap_wrapper (ctrl_t ctrl, ksba_reader_t *reader, const char *argv[])
|
||
{
|
||
gpg_error_t err;
|
||
pid_t pid;
|
||
struct wrapper_context_s *ctx;
|
||
int i;
|
||
int j;
|
||
const char **arg_list;
|
||
const char *pgmname;
|
||
int outpipe[2], errpipe[2];
|
||
|
||
/* It would be too simple to connect stderr just to our logging
|
||
stream. The problem is that if we are running multi-threaded
|
||
everything gets intermixed. Clearly we don't want this. So the
|
||
only viable solutions are either to have another thread
|
||
responsible for logging the messages or to add an option to the
|
||
wrapper module to do the logging on its own. Given that we anyway
|
||
need a way to reap the child process and this is best done using a
|
||
general reaping thread, that thread can do the logging too. */
|
||
ldap_wrapper_launch_thread ();
|
||
|
||
*reader = NULL;
|
||
|
||
/* Files: We need to prepare stdin and stdout. We get stderr from
|
||
the function. */
|
||
if (!opt.ldap_wrapper_program || !*opt.ldap_wrapper_program)
|
||
pgmname = gnupg_module_name (GNUPG_MODULE_NAME_DIRMNGR_LDAP);
|
||
else
|
||
pgmname = opt.ldap_wrapper_program;
|
||
|
||
/* Create command line argument array. */
|
||
for (i = 0; argv[i]; i++)
|
||
;
|
||
arg_list = xtrycalloc (i + 2, sizeof *arg_list);
|
||
if (!arg_list)
|
||
{
|
||
err = gpg_error_from_syserror ();
|
||
log_error (_("error allocating memory: %s\n"), strerror (errno));
|
||
return err;
|
||
}
|
||
for (i = j = 0; argv[i]; i++, j++)
|
||
if (!i && argv[i + 1] && !strcmp (*argv, "--pass"))
|
||
{
|
||
arg_list[j] = "--env-pass";
|
||
setenv ("DIRMNGR_LDAP_PASS", argv[1], 1);
|
||
i++;
|
||
}
|
||
else
|
||
arg_list[j] = (char*) argv[i];
|
||
|
||
ctx = xtrycalloc (1, sizeof *ctx);
|
||
if (!ctx)
|
||
{
|
||
err = gpg_error_from_syserror ();
|
||
log_error (_("error allocating memory: %s\n"), strerror (errno));
|
||
xfree (arg_list);
|
||
return err;
|
||
}
|
||
|
||
err = gnupg_create_inbound_pipe (outpipe, NULL, 0);
|
||
if (!err)
|
||
{
|
||
err = gnupg_create_inbound_pipe (errpipe, NULL, 0);
|
||
if (err)
|
||
{
|
||
close (outpipe[0]);
|
||
close (outpipe[1]);
|
||
}
|
||
}
|
||
if (err)
|
||
{
|
||
log_error (_("error creating a pipe: %s\n"), gpg_strerror (err));
|
||
xfree (arg_list);
|
||
xfree (ctx);
|
||
return err;
|
||
}
|
||
|
||
err = gnupg_spawn_process_fd (pgmname, arg_list,
|
||
-1, outpipe[1], errpipe[1], &pid);
|
||
xfree (arg_list);
|
||
close (outpipe[1]);
|
||
close (errpipe[1]);
|
||
if (err)
|
||
{
|
||
close (outpipe[0]);
|
||
close (errpipe[0]);
|
||
xfree (ctx);
|
||
return err;
|
||
}
|
||
|
||
ctx->pid = pid;
|
||
ctx->printable_pid = (int) pid;
|
||
ctx->fd = outpipe[0];
|
||
ctx->log_fd = errpipe[0];
|
||
ctx->ctrl = ctrl;
|
||
ctrl->refcount++;
|
||
ctx->stamp = time (NULL);
|
||
|
||
err = ksba_reader_new (reader);
|
||
if (!err)
|
||
err = ksba_reader_set_cb (*reader, reader_callback, ctx);
|
||
if (err)
|
||
{
|
||
log_error (_("error initializing reader object: %s\n"),
|
||
gpg_strerror (err));
|
||
destroy_wrapper (ctx);
|
||
ksba_reader_release (*reader);
|
||
*reader = NULL;
|
||
return err;
|
||
}
|
||
|
||
/* Hook the context into our list of running wrappers. */
|
||
ctx->reader = *reader;
|
||
ctx->next = wrapper_list;
|
||
wrapper_list = ctx;
|
||
if (opt.verbose)
|
||
log_info ("ldap wrapper %d started (reader %p)\n",
|
||
(int)ctx->pid, ctx->reader);
|
||
|
||
/* Need to wait for the first byte so we are able to detect an empty
|
||
output and not let the consumer see an EOF without further error
|
||
indications. The CRL loading logic assumes that after return
|
||
from this function, a failed search (e.g. host not found ) is
|
||
indicated right away. */
|
||
{
|
||
unsigned char c;
|
||
|
||
err = read_buffer (*reader, &c, 1);
|
||
if (err)
|
||
{
|
||
ldap_wrapper_release_context (*reader);
|
||
ksba_reader_release (*reader);
|
||
*reader = NULL;
|
||
if (gpg_err_code (err) == GPG_ERR_EOF)
|
||
return gpg_error (GPG_ERR_NO_DATA);
|
||
else
|
||
return err;
|
||
}
|
||
ksba_reader_unread (*reader, &c, 1);
|
||
}
|
||
|
||
return 0;
|
||
}
|