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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
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* Mandos plugin runner - Run Mandos plugins
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* Copyright © 2008-2020 Teddy Hogeborn
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* Copyright © 2008-2020 Björn Påhlsson
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* This file is part of Mandos.
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* Mandos is free software: you can redistribute it and/or modify it
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* 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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* Mandos is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@recompile.se>.
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
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#include <stddef.h> /* size_t, NULL */
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#include <stdlib.h> /* malloc(), reallocarray(), realloc(),
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EXIT_SUCCESS, exit() */
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#include <stdbool.h> /* bool, true, false */
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#include <stdio.h> /* fileno(), fprintf(),
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stderr, STDOUT_FILENO, fclose() */
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#include <sys/types.h> /* fstat(), struct stat, waitpid(),
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WIFEXITED(), WEXITSTATUS(), wait(),
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pid_t, uid_t, gid_t, getuid(),
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#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
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FD_SET(), FD_ISSET(), FD_CLR */
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#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
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WEXITSTATUS(), WTERMSIG() */
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#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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#include <iso646.h> /* and, or, not */
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#include <dirent.h> /* struct dirent, scandirat() */
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#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, write(), STDOUT_FILENO,
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struct stat, fstat(), close(),
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setgid(), setuid(), S_ISREG(),
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faccessat() pipe2(), fork(),
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_exit(), dup2(), fexecve(), read(),
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, openat(), scandirat(),
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#include <string.h> /* strsep, strlen(), strsignal(),
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strcmp(), strncmp() */
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#include <errno.h> /* errno */
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#include <argp.h> /* struct argp_option, struct
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argp_state, struct argp,
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argp_parse(), ARGP_ERR_UNKNOWN,
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ARGP_KEY_END, ARGP_KEY_ARG,
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#include <signal.h> /* struct sigaction, sigemptyset(),
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sigaddset(), sigaction(),
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sigprocmask(), SIG_BLOCK, SIGCHLD,
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SIG_UNBLOCK, kill(), sig_atomic_t
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#include <errno.h> /* errno, EBADF */
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#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
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EX_CONFIG, EX_UNAVAILABLE, EX_OK */
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#include <errno.h> /* errno */
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#include <error.h> /* error() */
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#include <fnmatch.h> /* fnmatch() */
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#define BUFFER_SIZE 256
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#define PDIR "/lib/mandos/plugins.d"
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#define PHDIR "/lib/mandos/plugin-helpers"
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#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
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const char *argp_program_version = "plugin-runner " VERSION;
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const char *argp_program_bug_address = "<mandos@recompile.se>";
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typedef struct plugin{
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char *name; /* can be NULL or any plugin name */
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/* Variables used for running processes*/
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#include <stdio.h> /* popen, fileno */
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#include <iso646.h> /* and, or, not */
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#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
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WIFEXITED, WEXITSTATUS, wait */
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#include <sys/wait.h> /* wait */
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#include <dirent.h> /* DIR, opendir */
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#include <sys/stat.h> /* stat, struct stat */
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#include <unistd.h> /* stat, struct stat, chdir */
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#include <stdlib.h> /* EXIT_FAILURE */
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#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET, FD_ISSET */
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#include <string.h> /* strlen, strcpy, strcat */
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#include <stdbool.h> /* true */
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#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
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#include <errno.h> /* errno */
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typedef struct process{
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volatile sig_atomic_t completed;
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static plugin *plugin_list = NULL;
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/* Gets an existing plugin based on name,
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or if none is found, creates a new one */
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__attribute__((warn_unused_result))
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static plugin *getplugin(char *name){
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/* Check for existing plugin with that name */
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for(plugin *p = plugin_list; p != NULL; p = p->next){
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or (p->name and name and (strcmp(p->name, name) == 0))){
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/* Create a new plugin */
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plugin *new_plugin = NULL;
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new_plugin = malloc(sizeof(plugin));
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} while(new_plugin == NULL and errno == EINTR);
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if(new_plugin == NULL){
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char *copy_name = NULL;
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copy_name = strdup(name);
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} while(copy_name == NULL and errno == EINTR);
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if(copy_name == NULL){
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*new_plugin = (plugin){ .name = copy_name,
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.next = plugin_list };
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new_plugin->argv = malloc(sizeof(char *) * 2);
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} while(new_plugin->argv == NULL and errno == EINTR);
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if(new_plugin->argv == NULL){
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new_plugin->argv[0] = copy_name;
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new_plugin->argv[1] = NULL;
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new_plugin->environ = malloc(sizeof(char *));
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} while(new_plugin->environ == NULL and errno == EINTR);
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if(new_plugin->environ == NULL){
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free(new_plugin->argv);
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new_plugin->environ[0] = NULL;
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/* Append the new plugin to the list */
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plugin_list = new_plugin;
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/* Helper function for add_argument and add_environment */
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__attribute__((nonnull, warn_unused_result))
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static bool add_to_char_array(const char *new, char ***array,
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/* Resize the pointed-to array to hold one more pointer */
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char **new_array = NULL;
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#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
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new_array = reallocarray(*array, (size_t)((*len) + 2),
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if(((size_t)((*len) + 2)) > (SIZE_MAX / sizeof(char *))){
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new_array = realloc(*array, (size_t)((*len) + 2)
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} while(new_array == NULL and errno == EINTR);
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if(new_array == NULL){
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/* Make a copy of the new string */
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} while(copy == NULL and errno == EINTR);
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/* Insert the copy */
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(*array)[*len] = copy;
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/* Add a new terminating NULL pointer to the last element */
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(*array)[*len] = NULL;
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/* Add to a plugin's argument vector */
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__attribute__((nonnull(2), warn_unused_result))
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static bool add_argument(plugin *p, const char *arg){
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return add_to_char_array(arg, &(p->argv), &(p->argc));
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/* Add to a plugin's environment */
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__attribute__((nonnull(2), warn_unused_result))
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static bool add_environment(plugin *p, const char *def, bool replace){
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/* namelen = length of name of environment variable */
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size_t namelen = (size_t)(strchrnul(def, '=') - def);
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/* Search for this environment variable */
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for(char **envdef = p->environ; *envdef != NULL; envdef++){
236
if(strncmp(*envdef, def, namelen + 1) == 0){
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/* It already exists */
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new_envdef = realloc(*envdef, strlen(def) + 1);
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} while(new_envdef == NULL and errno == EINTR);
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if(new_envdef == NULL){
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*envdef = new_envdef;
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strcpy(*envdef, def);
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return add_to_char_array(def, &(p->environ), &(p->envc));
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* Based on the example in the GNU LibC manual chapter 13.13 "File
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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
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__attribute__((warn_unused_result))
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static int set_cloexec_flag(int fd){
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int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
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/* If reading the flags failed, return error indication now. */
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/* Store modified flag word in the descriptor. */
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return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
272
#endif /* not O_CLOEXEC */
275
/* Mark processes as completed when they exit, and save their exit
277
static void handle_sigchld(__attribute__((unused)) int sig){
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int old_errno = errno;
280
plugin *proc = plugin_list;
282
pid_t pid = waitpid(-1, &status, WNOHANG);
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/* Only still running child processes */
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/* No child processes */
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error(0, errno, "waitpid");
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/* A child exited, find it in process_list */
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while(proc != NULL and proc->pid != pid){
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/* Process not found in process list */
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proc->status = status;
309
/* Prints out a password to stdout */
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__attribute__((nonnull, warn_unused_result))
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static bool print_out_password(const char *buffer, size_t length){
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for(size_t written = 0; written < length; written += (size_t)ret){
314
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
323
/* Removes and free a plugin from the plugin list */
324
__attribute__((nonnull))
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static void free_plugin(plugin *plugin_node){
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for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
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free(plugin_node->name);
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free(plugin_node->argv);
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for(char **env = plugin_node->environ; *env != NULL; env++){
335
free(plugin_node->environ);
336
free(plugin_node->buffer);
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/* Removes the plugin from the singly-linked list */
339
if(plugin_node == plugin_list){
340
/* First one - simple */
341
plugin_list = plugin_list->next;
343
/* Second one or later */
344
for(plugin *p = plugin_list; p != NULL; p = p->next){
345
if(p->next == plugin_node){
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p->next = plugin_node->next;
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static void free_plugin_list(void){
356
while(plugin_list != NULL){
357
free_plugin(plugin_list);
27
#define BUFFER_SIZE 256
361
29
int main(int argc, char *argv[]){
362
char *plugindir = NULL;
363
char *pluginhelperdir = NULL;
364
char *argfile = NULL;
366
struct dirent **direntries = NULL;
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char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
369
36
int ret, maxfd = 0;
374
int exitstatus = EXIT_SUCCESS;
375
struct sigaction old_sigchld_action;
376
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
377
.sa_flags = SA_NOCLDSTOP };
378
char **custom_argv = NULL;
382
/* Establish a signal handler */
383
sigemptyset(&sigchld_action.sa_mask);
384
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
386
error(0, errno, "sigaddset");
387
exitstatus = EX_OSERR;
390
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
392
error(0, errno, "sigaction");
393
exitstatus = EX_OSERR;
397
/* The options we understand. */
398
struct argp_option options[] = {
399
{ .name = "global-options", .key = 'g',
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.arg = "OPTION[,OPTION[,...]]",
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.doc = "Options passed to all plugins" },
402
{ .name = "global-env", .key = 'G',
404
.doc = "Environment variable passed to all plugins" },
405
{ .name = "options-for", .key = 'o',
406
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
407
.doc = "Options passed only to specified plugin" },
408
{ .name = "env-for", .key = 'E',
409
.arg = "PLUGIN:ENV=value",
410
.doc = "Environment variable passed to specified plugin" },
411
{ .name = "disable", .key = 'd',
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.doc = "Disable a specific plugin", .group = 1 },
414
{ .name = "enable", .key = 'e',
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.doc = "Enable a specific plugin", .group = 1 },
417
{ .name = "plugin-dir", .key = 128,
419
.doc = "Specify a different plugin directory", .group = 2 },
420
{ .name = "config-file", .key = 129,
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.doc = "Specify a different configuration file", .group = 2 },
423
{ .name = "userid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 3 },
426
{ .name = "groupid", .key = 131,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 3 },
429
{ .name = "debug", .key = 132,
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.doc = "Debug mode", .group = 4 },
431
{ .name = "plugin-helper-dir", .key = 133,
433
.doc = "Specify a different plugin helper directory",
436
* These reproduce what we would get without ARGP_NO_HELP
438
{ .name = "help", .key = '?',
439
.doc = "Give this help list", .group = -1 },
440
{ .name = "usage", .key = -3,
441
.doc = "Give a short usage message", .group = -1 },
442
{ .name = "version", .key = 'V',
443
.doc = "Print program version", .group = -1 },
447
__attribute__((nonnull(3)))
448
error_t parse_opt(int key, char *arg, struct argp_state *state){
453
case 'g': /* --global-options */
456
while((plugin_option = strsep(&arg, ",")) != NULL){
457
if(not add_argument(getplugin(NULL), plugin_option)){
464
case 'G': /* --global-env */
465
if(add_environment(getplugin(NULL), arg, true)){
469
case 'o': /* --options-for */
471
char *option_list = strchr(arg, ':');
472
if(option_list == NULL){
473
argp_error(state, "No colon in \"%s\"", arg);
480
argp_error(state, "Empty plugin name");
485
while((option = strsep(&option_list, ",")) != NULL){
486
if(not add_argument(getplugin(arg), option)){
493
case 'E': /* --env-for */
495
char *envdef = strchr(arg, ':');
497
argp_error(state, "No colon in \"%s\"", arg);
504
argp_error(state, "Empty plugin name");
508
if(add_environment(getplugin(arg), envdef, true)){
513
case 'd': /* --disable */
515
plugin *p = getplugin(arg);
522
case 'e': /* --enable */
524
plugin *p = getplugin(arg);
531
case 128: /* --plugin-dir */
533
plugindir = strdup(arg);
534
if(plugindir != NULL){
538
case 129: /* --config-file */
539
/* This is already done by parse_opt_config_file() */
541
case 130: /* --userid */
542
tmp_id = strtoimax(arg, &tmp, 10);
543
if(errno != 0 or tmp == arg or *tmp != '\0'
544
or tmp_id != (uid_t)tmp_id){
545
argp_error(state, "Bad user ID number: \"%s\", using %"
546
PRIdMAX, arg, (intmax_t)uid);
552
case 131: /* --groupid */
553
tmp_id = strtoimax(arg, &tmp, 10);
554
if(errno != 0 or tmp == arg or *tmp != '\0'
555
or tmp_id != (gid_t)tmp_id){
556
argp_error(state, "Bad group ID number: \"%s\", using %"
557
PRIdMAX, arg, (intmax_t)gid);
563
case 132: /* --debug */
566
case 133: /* --plugin-helper-dir */
567
free(pluginhelperdir);
568
pluginhelperdir = strdup(arg);
569
if(pluginhelperdir != NULL){
574
* These reproduce what we would get without ARGP_NO_HELP
576
case '?': /* --help */
577
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
578
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
579
__builtin_unreachable();
580
case -3: /* --usage */
581
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
582
argp_state_help(state, state->out_stream,
583
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
584
__builtin_unreachable();
585
case 'V': /* --version */
586
fprintf(state->out_stream, "%s\n", argp_program_version);
590
* When adding more options before this line, remember to also add a
591
* "case" to the "parse_opt_config_file" function below.
594
/* Cryptsetup always passes an argument, which is an empty
595
string if "none" was specified in /etc/crypttab. So if
596
argument was empty, we ignore it silently. */
601
__attribute__((fallthrough));
606
return ARGP_ERR_UNKNOWN;
608
return errno; /* Set to 0 at start */
611
/* This option parser is the same as parse_opt() above, except it
612
ignores everything but the --config-file option. */
613
error_t parse_opt_config_file(int key, char *arg,
614
__attribute__((unused))
615
struct argp_state *state){
618
case 'g': /* --global-options */
619
case 'G': /* --global-env */
620
case 'o': /* --options-for */
621
case 'E': /* --env-for */
622
case 'd': /* --disable */
623
case 'e': /* --enable */
624
case 128: /* --plugin-dir */
626
case 129: /* --config-file */
628
argfile = strdup(arg);
633
case 130: /* --userid */
634
case 131: /* --groupid */
635
case 132: /* --debug */
636
case 133: /* --plugin-helper-dir */
637
case '?': /* --help */
638
case -3: /* --usage */
639
case 'V': /* --version */
643
return ARGP_ERR_UNKNOWN;
648
struct argp argp = { .options = options,
649
.parser = parse_opt_config_file,
651
.doc = "Mandos plugin runner -- Run plugins" };
653
/* Parse using parse_opt_config_file() in order to get the custom
654
config file location, if any. */
655
ret = argp_parse(&argp, argc, argv,
656
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
664
error(0, errno, "argp_parse");
665
exitstatus = EX_OSERR;
668
exitstatus = EX_USAGE;
672
/* Reset to the normal argument parser */
673
argp.parser = parse_opt;
675
/* Open the configfile if available */
677
conffp = fopen(AFILE, "r");
679
conffp = fopen(argfile, "r");
682
char *org_line = NULL;
683
char *p, *arg, *new_arg, *line;
685
const char whitespace_delims[] = " \r\t\f\v\n";
686
const char comment_delim[] = "#";
689
custom_argv = malloc(sizeof(char*) * 2);
690
if(custom_argv == NULL){
691
error(0, errno, "malloc");
692
exitstatus = EX_OSERR;
695
custom_argv[0] = argv[0];
696
custom_argv[1] = NULL;
698
/* for each line in the config file, strip whitespace and ignore
37
process *process_list = NULL;
39
dir = opendir(plugindir);
42
fprintf(stderr, "Can not open directory\n");
51
// All directory entries have been processed
56
d_name_len = strlen(dirst->d_name);
58
// Ignore dotfiles and backup files
59
if (dirst->d_name[0] == '.'
60
or dirst->d_name[d_name_len - 1] == '~'){
64
char *filename = malloc(d_name_len + plugindir_len + 1);
65
strcpy(filename, plugindir);
66
strcat(filename, "/");
67
strcat(filename, dirst->d_name);
71
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
72
// Starting a new process to be watched
73
process *new_process = malloc(sizeof(process));
76
new_process->pid = fork();
77
if(new_process->pid == 0){
78
/* this is the child process */
80
close(pipefd[0]); /* close unused read end of pipe */
81
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
82
/* create a new modified argument list */
83
char **new_argv = malloc(sizeof(char *) * argc + 1);
84
new_argv[0] = filename;
85
for(int i = 1; i < argc; i++){
86
new_argv[i] = argv[i];
88
new_argv[argc] = NULL;
89
if(execv(filename, new_argv) < 0){
96
close(pipefd[1]); /* close unused write end of pipe */
97
new_process->fd = pipefd[0];
98
new_process->buffer = malloc(BUFFER_SIZE);
99
if (new_process->buffer == NULL){
103
new_process->buffer_size = BUFFER_SIZE;
104
new_process->buffer_length = 0;
105
FD_SET(new_process->fd, &rfds_orig);
107
if (maxfd < new_process->fd){
108
maxfd = new_process->fd;
112
new_process->next = process_list;
113
process_list = new_process;
119
if (process_list != NULL){
701
sret = getline(&org_line, &size, conffp);
707
arg = strsep(&line, comment_delim);
708
while((p = strsep(&arg, whitespace_delims)) != NULL){
714
error(0, errno, "strdup");
715
exitstatus = EX_OSERR;
722
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
723
char **new_argv = reallocarray(custom_argv, (size_t)custom_argc + 1,
726
char **new_argv = NULL;
727
if(((size_t)custom_argc + 1) > (SIZE_MAX / sizeof(char *))){
731
new_argv = realloc(custom_argv, ((size_t)custom_argc + 1)
735
if(new_argv == NULL){
736
error(0, errno, "reallocarray");
737
exitstatus = EX_OSERR;
742
custom_argv = new_argv;
745
custom_argv[custom_argc-1] = new_arg;
746
custom_argv[custom_argc] = NULL;
750
ret = fclose(conffp);
751
} while(ret == EOF and errno == EINTR);
753
error(0, errno, "fclose");
754
exitstatus = EX_IOERR;
759
/* Check for harmful errors and go to fallback. Other errors might
760
not affect opening plugins */
761
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
762
error(0, errno, "fopen");
763
exitstatus = EX_OSERR;
767
/* If there were any arguments from the configuration file, pass
768
them to parser as command line arguments */
769
if(custom_argv != NULL){
770
ret = argp_parse(&argp, custom_argc, custom_argv,
771
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
779
error(0, errno, "argp_parse");
780
exitstatus = EX_OSERR;
783
exitstatus = EX_CONFIG;
788
/* Parse actual command line arguments, to let them override the
790
ret = argp_parse(&argp, argc, argv,
791
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
799
error(0, errno, "argp_parse");
800
exitstatus = EX_OSERR;
803
exitstatus = EX_USAGE;
808
char *pluginhelperenv;
810
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
811
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
813
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
815
if(ret == -1 or not bret){
816
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
817
" environment variable to \"%s\" for all plugins\n",
818
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
821
free(pluginhelperenv);
826
for(plugin *p = plugin_list; p != NULL; p = p->next){
827
fprintf(stderr, "Plugin: %s has %d arguments\n",
828
p->name ? p->name : "Global", p->argc - 1);
829
for(char **a = p->argv; *a != NULL; a++){
830
fprintf(stderr, "\tArg: %s\n", *a);
832
fprintf(stderr, "...and %d environment variables\n", p->envc);
833
for(char **a = p->environ; *a != NULL; a++){
834
fprintf(stderr, "\t%s\n", *a);
840
/* Work around Debian bug #633582:
841
<https://bugs.debian.org/633582> */
842
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
843
if(plugindir_fd == -1){
845
error(0, errno, "open(\"" PDIR "\")");
848
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
850
error(0, errno, "fstat");
852
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
853
ret = fchown(plugindir_fd, uid, gid);
855
error(0, errno, "fchown");
862
/* Work around Debian bug #981302
863
<https://bugs.debian.org/981302> */
864
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
865
ret = symlink("/proc/self/fd", "/dev/fd");
867
error(0, errno, "Failed to create /dev/fd symlink");
872
/* Lower permissions */
875
error(0, errno, "setgid");
879
error(0, errno, "setuid");
882
/* Open plugin directory with close_on_exec flag */
884
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
887
#else /* not O_CLOEXEC */
889
#endif /* not O_CLOEXEC */
892
error(0, errno, "Could not open plugin dir");
893
exitstatus = EX_UNAVAILABLE;
898
/* Set the FD_CLOEXEC flag on the directory */
899
ret = set_cloexec_flag(dir_fd);
901
error(0, errno, "set_cloexec_flag");
902
exitstatus = EX_OSERR;
905
#endif /* O_CLOEXEC */
908
int good_name(const struct dirent * const dirent){
909
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
910
"*.dpkg-old", "*.dpkg-bak",
911
"*.dpkg-divert", NULL };
913
#pragma GCC diagnostic push
914
#pragma GCC diagnostic ignored "-Wcast-qual"
916
for(const char **pat = (const char **)patterns;
917
*pat != NULL; pat++){
919
#pragma GCC diagnostic pop
921
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
924
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
925
" matching pattern %s\n", dirent->d_name, *pat);
933
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
935
if(numplugins == -1){
936
error(0, errno, "Could not scan plugin dir");
938
exitstatus = EX_OSERR;
944
/* Read and execute any executable in the plugin directory*/
945
for(int i = 0; i < numplugins; i++){
947
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
949
error(0, errno, "Could not open plugin");
953
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
955
error(0, errno, "stat");
961
/* Ignore non-executable files */
962
if(not S_ISREG(st.st_mode)
963
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
966
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
967
" with bad type or mode\n",
968
plugindir != NULL ? plugindir : PDIR,
969
direntries[i]->d_name);
976
plugin *p = getplugin(direntries[i]->d_name);
978
error(0, errno, "getplugin");
985
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
986
direntries[i]->d_name);
993
/* Add global arguments to argument list for this plugin */
994
plugin *g = getplugin(NULL);
996
for(char **a = g->argv + 1; *a != NULL; a++){
997
if(not add_argument(p, *a)){
998
error(0, errno, "add_argument");
1001
/* Add global environment variables */
1002
for(char **e = g->environ; *e != NULL; e++){
1003
if(not add_environment(p, *e, false)){
1004
error(0, errno, "add_environment");
1009
/* If this plugin has any environment variables, we need to
1010
duplicate the environment from this process, too. */
1011
if(p->environ[0] != NULL){
1012
for(char **e = environ; *e != NULL; e++){
1013
if(not add_environment(p, *e, false)){
1014
error(0, errno, "add_environment");
1021
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1022
#else /* O_CLOEXEC */
1023
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1024
#endif /* O_CLOEXEC */
1026
error(0, errno, "pipe");
1027
exitstatus = EX_OSERR;
1028
free(direntries[i]);
1031
if(pipefd[0] >= FD_SETSIZE){
1032
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1036
exitstatus = EX_OSERR;
1037
free(direntries[i]);
1041
/* Ask OS to automatic close the pipe on exec */
1042
ret = set_cloexec_flag(pipefd[0]);
1044
error(0, errno, "set_cloexec_flag");
1047
exitstatus = EX_OSERR;
1048
free(direntries[i]);
1051
ret = set_cloexec_flag(pipefd[1]);
1053
error(0, errno, "set_cloexec_flag");
1056
exitstatus = EX_OSERR;
1057
free(direntries[i]);
1060
#endif /* not O_CLOEXEC */
1061
/* Block SIGCHLD until process is safely in process list */
1062
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1063
&sigchld_action.sa_mask,
1066
error(0, errno, "sigprocmask");
1067
exitstatus = EX_OSERR;
1068
free(direntries[i]);
1071
/* Starting a new process to be watched */
1075
} while(pid == -1 and errno == EINTR);
1077
error(0, errno, "fork");
1078
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1079
&sigchld_action.sa_mask, NULL));
1082
exitstatus = EX_OSERR;
1083
free(direntries[i]);
1087
/* this is the child process */
1088
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1090
error(0, errno, "sigaction");
1093
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1095
error(0, errno, "sigprocmask");
1099
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1101
error(0, errno, "dup2");
1105
if(fexecve(plugin_fd, p->argv,
1106
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1107
error(0, errno, "fexecve for %s/%s",
1108
plugindir != NULL ? plugindir : PDIR,
1109
direntries[i]->d_name);
1114
/* Parent process */
1115
close(pipefd[1]); /* Close unused write end of pipe */
1117
plugin *new_plugin = getplugin(direntries[i]->d_name);
1118
if(new_plugin == NULL){
1119
error(0, errno, "getplugin");
1120
ret = (int)(TEMP_FAILURE_RETRY
1121
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1124
error(0, errno, "sigprocmask");
1126
exitstatus = EX_OSERR;
1127
free(direntries[i]);
1130
free(direntries[i]);
1132
new_plugin->pid = pid;
1133
new_plugin->fd = pipefd[0];
1136
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1137
new_plugin->name, (intmax_t) (new_plugin->pid));
1140
/* Unblock SIGCHLD so signal handler can be run if this process
1141
has already completed */
1142
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1143
&sigchld_action.sa_mask,
1146
error(0, errno, "sigprocmask");
1147
exitstatus = EX_OSERR;
1151
FD_SET(new_plugin->fd, &rfds_all);
1153
if(maxfd < new_plugin->fd){
1154
maxfd = new_plugin->fd;
1162
free_plugin(getplugin(NULL));
1164
for(plugin *p = plugin_list; p != NULL; p = p->next){
1168
if(p->next == NULL){
1169
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1175
/* Main loop while running plugins exist */
1177
fd_set rfds = rfds_all;
1178
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1179
if(select_ret == -1 and errno != EINTR){
1180
error(0, errno, "select");
1181
exitstatus = EX_OSERR;
1184
/* OK, now either a process completed, or something can be read
1186
for(plugin *proc = plugin_list; proc != NULL;){
1187
/* Is this process completely done? */
1188
if(proc->completed and proc->eof){
1189
/* Only accept the plugin output if it exited cleanly */
1190
if(not WIFEXITED(proc->status)
1191
or WEXITSTATUS(proc->status) != 0){
1192
/* Bad exit by plugin */
1195
if(WIFEXITED(proc->status)){
1196
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1197
" status %d\n", proc->name,
1198
(intmax_t) (proc->pid),
1199
WEXITSTATUS(proc->status));
1200
} else if(WIFSIGNALED(proc->status)){
1201
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1202
" signal %d: %s\n", proc->name,
1203
(intmax_t) (proc->pid),
1204
WTERMSIG(proc->status),
1205
strsignal(WTERMSIG(proc->status)));
1209
/* Remove the plugin */
1210
FD_CLR(proc->fd, &rfds_all);
1212
/* Block signal while modifying process_list */
1213
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1215
&sigchld_action.sa_mask,
1218
error(0, errno, "sigprocmask");
1219
exitstatus = EX_OSERR;
1223
plugin *next_plugin = proc->next;
1227
/* We are done modifying process list, so unblock signal */
1228
ret = (int)(TEMP_FAILURE_RETRY
1229
(sigprocmask(SIG_UNBLOCK,
1230
&sigchld_action.sa_mask, NULL)));
1232
error(0, errno, "sigprocmask");
1233
exitstatus = EX_OSERR;
1237
if(plugin_list == NULL){
1244
/* This process exited nicely, so print its buffer */
1246
bool bret = print_out_password(proc->buffer,
1247
proc->buffer_length);
1249
error(0, errno, "print_out_password");
1250
exitstatus = EX_IOERR;
1255
/* This process has not completed. Does it have any output? */
1256
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1257
/* This process had nothing to say at this time */
1261
/* Before reading, make the process' data buffer large enough */
1262
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1263
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1264
+ (size_t) BUFFER_SIZE);
1265
if(new_buffer == NULL){
1266
error(0, errno, "malloc");
1267
exitstatus = EX_OSERR;
1270
proc->buffer = new_buffer;
1271
proc->buffer_size += BUFFER_SIZE;
1273
/* Read from the process */
1274
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1276
+ proc->buffer_length,
1279
/* Read error from this process; ignore the error */
1287
proc->buffer_length += (size_t) sret;
1295
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1296
and exitstatus != EX_OK)){
1297
/* Fallback if all plugins failed, none are found or an error
1300
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1301
char *passwordbuffer = getpass("Password: ");
1302
size_t len = strlen(passwordbuffer);
1303
/* Strip trailing newline */
1304
if(len > 0 and passwordbuffer[len-1] == '\n'){
1305
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1308
bret = print_out_password(passwordbuffer, len);
1310
error(0, errno, "print_out_password");
1311
exitstatus = EX_IOERR;
1315
/* Restore old signal handler */
1316
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1318
error(0, errno, "sigaction");
1319
exitstatus = EX_OSERR;
1322
if(custom_argv != NULL){
1323
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1335
/* Kill the processes */
1336
for(plugin *p = plugin_list; p != NULL; p = p->next){
1339
ret = kill(p->pid, SIGTERM);
1340
if(ret == -1 and errno != ESRCH){
1341
/* Set-uid proccesses might not get closed */
1342
error(0, errno, "kill");
1347
/* Wait for any remaining child processes to terminate */
1351
if(errno != ECHILD){
1352
error(0, errno, "wait");
1358
free(pluginhelperdir);
121
fd_set rfds = rfds_orig;
122
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
123
if (select_ret == -1){
127
for(process *process_itr = process_list; process_itr != NULL;
128
process_itr = process_itr->next){
129
if(FD_ISSET(process_itr->fd, &rfds)){
130
if(process_itr->buffer_length + BUFFER_SIZE
131
> process_itr->buffer_size){
132
process_itr->buffer = realloc(process_itr->buffer,
133
process_itr->buffer_size
135
if (process_itr->buffer == NULL){
139
process_itr->buffer_size += BUFFER_SIZE;
141
ret = read(process_itr->fd, process_itr->buffer
142
+ process_itr->buffer_length, BUFFER_SIZE);
143
process_itr->buffer_length+=ret;
146
/* wait for process exit */
148
waitpid(process_itr->pid, &status, 0);
149
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
150
write(STDOUT_FILENO, process_itr->buffer,
151
process_itr->buffer_length);
154
FD_CLR(process_itr->fd, &rfds_orig);
164
for(process *process_itr = process_list; process_itr != NULL;
165
process_itr = process_itr->next){
166
close(process_itr->fd);
167
kill(process_itr->pid, SIGTERM);
168
free(process_itr->buffer);