1
/* -*- coding: utf-8 -*- */
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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
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3
* Mandos plugin runner - Run Mandos plugins
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* Copyright © 2007-2008 Teddy Hogeborn and Björn Påhlsson.
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* This program is free software: you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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* This program is distributed in the hope that it will be useful, but
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* Copyright © 2008-2018 Teddy Hogeborn
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* Copyright © 2008-2018 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
13
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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18
* General Public License for more details.
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20
* You should have received a copy of the GNU General Public License
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
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* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
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* Contact the authors at <mandos@recompile.se>.
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#define _FORTIFY_SOURCE 2
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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,
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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 */
41
#include <errno.h> /* errno */
45
typedef struct process{
26
#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() */
31
#include <stdbool.h> /* bool, true, false */
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#include <stdio.h> /* fileno(), fprintf(),
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stderr, STDOUT_FILENO, fclose() */
34
#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 */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
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WEXITSTATUS(), WTERMSIG() */
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#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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size_t buffer_size;
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size_t buffer_length;
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#define BUFFER_SIZE 256
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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 *));
159
} 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);
168
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))
177
static bool add_to_char_array(const char *new, char ***array,
179
/* Resize the pointed-to array to hold one more pointer */
180
char **new_array = NULL;
182
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
183
new_array = reallocarray(*array, (size_t)((*len) + 2),
186
if(((size_t)((*len) + 2)) > (SIZE_MAX / sizeof(char *))){
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new_array = realloc(*array, (size_t)((*len) + 2)
195
} while(new_array == NULL and errno == EINTR);
197
if(new_array == NULL){
201
/* Make a copy of the new string */
205
} while(copy == NULL and errno == EINTR);
209
/* Insert the copy */
210
(*array)[*len] = copy;
212
/* Add a new terminating NULL pointer to the last element */
213
(*array)[*len] = NULL;
217
/* Add to a plugin's argument vector */
218
__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));
226
/* Add to a plugin's environment */
227
__attribute__((nonnull(2), warn_unused_result))
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static bool add_environment(plugin *p, const char *def, bool replace){
232
/* namelen = length of name of environment variable */
233
size_t namelen = (size_t)(strchrnul(def, '=') - def);
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/* Search for this environment variable */
235
for(char **envdef = p->environ; *envdef != NULL; envdef++){
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if(strncmp(*envdef, def, namelen + 1) == 0){
237
/* It already exists */
241
new_envdef = realloc(*envdef, strlen(def) + 1);
242
} while(new_envdef == NULL and errno == EINTR);
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if(new_envdef == NULL){
246
*envdef = new_envdef;
247
strcpy(*envdef, def);
252
return add_to_char_array(def, &(p->environ), &(p->envc));
257
* Based on the example in the GNU LibC manual chapter 13.13 "File
259
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
261
__attribute__((warn_unused_result))
262
static int set_cloexec_flag(int fd){
263
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
264
/* If reading the flags failed, return error indication now. */
268
/* Store modified flag word in the descriptor. */
269
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
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#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){
278
int old_errno = errno;
280
plugin *proc = plugin_list;
282
pid_t pid = waitpid(-1, &status, WNOHANG);
284
/* Only still running child processes */
289
/* No child processes */
292
error(0, errno, "waitpid");
295
/* A child exited, find it in process_list */
296
while(proc != NULL and proc->pid != pid){
300
/* Process not found in process list */
303
proc->status = status;
309
/* Prints out a password to stdout */
310
__attribute__((nonnull, warn_unused_result))
311
static bool print_out_password(const char *buffer, size_t length){
313
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){
327
for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
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free(plugin_node->name);
331
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);
338
/* 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){
346
p->next = plugin_node->next;
355
static void free_plugin_list(void){
356
while(plugin_list != NULL){
357
free_plugin(plugin_list);
56
361
int main(int argc, char *argv[]){
57
char plugindir[] = "plugins.d";
58
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
362
char *plugindir = NULL;
363
char *pluginhelperdir = NULL;
364
char *argfile = NULL;
366
struct dirent **direntries = NULL;
63
369
int ret, maxfd = 0;
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process *process_list = NULL;
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dir = opendir(plugindir);
69
fprintf(stderr, "Can not open directory\n");
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// All directory entries have been processed
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d_name_len = strlen(dirst->d_name);
85
// Ignore dotfiles and backup files
86
if (dirst->d_name[0] == '.'
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or dirst->d_name[d_name_len - 1] == '~'){
91
char *filename = malloc(d_name_len + plugindir_len + 2);
92
strcpy(filename, plugindir);
93
strcat(filename, "/");
94
strcat(filename, dirst->d_name);
98
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
99
// Starting a new process to be watched
100
process *new_process = malloc(sizeof(process));
103
new_process->pid = fork();
104
if(new_process->pid == 0){
105
/* this is the child process */
107
close(pipefd[0]); /* close unused read end of pipe */
108
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
109
/* create a new modified argument list */
110
char **new_argv = malloc(sizeof(char *)
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* ((unsigned int) argc + 1));
112
new_argv[0] = filename;
113
for(int i = 1; i < argc; i++){
114
new_argv[i] = argv[i];
116
new_argv[argc] = NULL;
117
if(execv(filename, new_argv) < 0){
124
close(pipefd[1]); /* close unused write end of pipe */
125
new_process->fd = pipefd[0];
126
new_process->buffer = malloc(BUFFER_SIZE);
127
if (new_process->buffer == NULL){
131
new_process->buffer_size = BUFFER_SIZE;
132
new_process->buffer_length = 0;
133
FD_SET(new_process->fd, &rfds_orig);
135
if (maxfd < new_process->fd){
136
maxfd = new_process->fd;
140
new_process->next = process_list;
141
process_list = new_process;
147
if (process_list != NULL){
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',
400
.arg = "OPTION[,OPTION[,...]]",
401
.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',
413
.doc = "Disable a specific plugin", .group = 1 },
414
{ .name = "enable", .key = 'e',
416
.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,
422
.doc = "Specify a different configuration file", .group = 2 },
423
{ .name = "userid", .key = 130,
424
.arg = "ID", .flags = 0,
425
.doc = "User ID the plugins will run as", .group = 3 },
426
{ .name = "groupid", .key = 131,
427
.arg = "ID", .flags = 0,
428
.doc = "Group ID the plugins will run as", .group = 3 },
429
{ .name = "debug", .key = 132,
430
.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
149
fd_set rfds = rfds_orig;
150
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
151
if (select_ret == -1){
155
for(process *process_itr = process_list; process_itr != NULL;
156
process_itr = process_itr->next){
157
if(FD_ISSET(process_itr->fd, &rfds)){
158
if(process_itr->buffer_length + BUFFER_SIZE
159
> process_itr->buffer_size){
160
process_itr->buffer = realloc(process_itr->buffer,
161
process_itr->buffer_size
162
+ (size_t) BUFFER_SIZE);
163
if (process_itr->buffer == NULL){
167
process_itr->buffer_size += BUFFER_SIZE;
169
ret = read(process_itr->fd, process_itr->buffer
170
+ process_itr->buffer_length, BUFFER_SIZE);
172
/* Read error from this process; ignore it */
175
process_itr->buffer_length += (size_t) ret;
178
/* wait for process exit */
180
waitpid(process_itr->pid, &status, 0);
181
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
182
write(STDOUT_FILENO, process_itr->buffer,
183
process_itr->buffer_length);
186
FD_CLR(process_itr->fd, &rfds_orig);
196
for(process *process_itr = process_list; process_itr != NULL;
197
process_itr = process_itr->next){
198
close(process_itr->fd);
199
kill(process_itr->pid, SIGTERM);
200
free(process_itr->buffer);
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");
863
/* Lower permissions */
866
error(0, errno, "setgid");
870
error(0, errno, "setuid");
873
/* Open plugin directory with close_on_exec flag */
875
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
878
#else /* not O_CLOEXEC */
880
#endif /* not O_CLOEXEC */
883
error(0, errno, "Could not open plugin dir");
884
exitstatus = EX_UNAVAILABLE;
889
/* Set the FD_CLOEXEC flag on the directory */
890
ret = set_cloexec_flag(dir_fd);
892
error(0, errno, "set_cloexec_flag");
893
exitstatus = EX_OSERR;
896
#endif /* O_CLOEXEC */
899
int good_name(const struct dirent * const dirent){
900
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
901
"*.dpkg-old", "*.dpkg-bak",
902
"*.dpkg-divert", NULL };
904
#pragma GCC diagnostic push
905
#pragma GCC diagnostic ignored "-Wcast-qual"
907
for(const char **pat = (const char **)patterns;
908
*pat != NULL; pat++){
910
#pragma GCC diagnostic pop
912
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
915
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
916
" matching pattern %s\n", dirent->d_name, *pat);
924
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
926
if(numplugins == -1){
927
error(0, errno, "Could not scan plugin dir");
929
exitstatus = EX_OSERR;
935
/* Read and execute any executable in the plugin directory*/
936
for(int i = 0; i < numplugins; i++){
938
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
940
error(0, errno, "Could not open plugin");
944
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
946
error(0, errno, "stat");
952
/* Ignore non-executable files */
953
if(not S_ISREG(st.st_mode)
954
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
957
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
958
" with bad type or mode\n",
959
plugindir != NULL ? plugindir : PDIR,
960
direntries[i]->d_name);
967
plugin *p = getplugin(direntries[i]->d_name);
969
error(0, errno, "getplugin");
976
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
977
direntries[i]->d_name);
984
/* Add global arguments to argument list for this plugin */
985
plugin *g = getplugin(NULL);
987
for(char **a = g->argv + 1; *a != NULL; a++){
988
if(not add_argument(p, *a)){
989
error(0, errno, "add_argument");
992
/* Add global environment variables */
993
for(char **e = g->environ; *e != NULL; e++){
994
if(not add_environment(p, *e, false)){
995
error(0, errno, "add_environment");
1000
/* If this plugin has any environment variables, we need to
1001
duplicate the environment from this process, too. */
1002
if(p->environ[0] != NULL){
1003
for(char **e = environ; *e != NULL; e++){
1004
if(not add_environment(p, *e, false)){
1005
error(0, errno, "add_environment");
1012
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1013
#else /* O_CLOEXEC */
1014
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1015
#endif /* O_CLOEXEC */
1017
error(0, errno, "pipe");
1018
exitstatus = EX_OSERR;
1019
free(direntries[i]);
1022
if(pipefd[0] >= FD_SETSIZE){
1023
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1027
exitstatus = EX_OSERR;
1028
free(direntries[i]);
1032
/* Ask OS to automatic close the pipe on exec */
1033
ret = set_cloexec_flag(pipefd[0]);
1035
error(0, errno, "set_cloexec_flag");
1038
exitstatus = EX_OSERR;
1039
free(direntries[i]);
1042
ret = set_cloexec_flag(pipefd[1]);
1044
error(0, errno, "set_cloexec_flag");
1047
exitstatus = EX_OSERR;
1048
free(direntries[i]);
1051
#endif /* not O_CLOEXEC */
1052
/* Block SIGCHLD until process is safely in process list */
1053
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1054
&sigchld_action.sa_mask,
1057
error(0, errno, "sigprocmask");
1058
exitstatus = EX_OSERR;
1059
free(direntries[i]);
1062
/* Starting a new process to be watched */
1066
} while(pid == -1 and errno == EINTR);
1068
error(0, errno, "fork");
1069
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1070
&sigchld_action.sa_mask, NULL));
1073
exitstatus = EX_OSERR;
1074
free(direntries[i]);
1078
/* this is the child process */
1079
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1081
error(0, errno, "sigaction");
1084
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1086
error(0, errno, "sigprocmask");
1090
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1092
error(0, errno, "dup2");
1096
if(fexecve(plugin_fd, p->argv,
1097
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1098
error(0, errno, "fexecve for %s/%s",
1099
plugindir != NULL ? plugindir : PDIR,
1100
direntries[i]->d_name);
1105
/* Parent process */
1106
close(pipefd[1]); /* Close unused write end of pipe */
1108
plugin *new_plugin = getplugin(direntries[i]->d_name);
1109
if(new_plugin == NULL){
1110
error(0, errno, "getplugin");
1111
ret = (int)(TEMP_FAILURE_RETRY
1112
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1115
error(0, errno, "sigprocmask");
1117
exitstatus = EX_OSERR;
1118
free(direntries[i]);
1121
free(direntries[i]);
1123
new_plugin->pid = pid;
1124
new_plugin->fd = pipefd[0];
1127
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1128
new_plugin->name, (intmax_t) (new_plugin->pid));
1131
/* Unblock SIGCHLD so signal handler can be run if this process
1132
has already completed */
1133
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1134
&sigchld_action.sa_mask,
1137
error(0, errno, "sigprocmask");
1138
exitstatus = EX_OSERR;
1142
FD_SET(new_plugin->fd, &rfds_all);
1144
if(maxfd < new_plugin->fd){
1145
maxfd = new_plugin->fd;
1153
free_plugin(getplugin(NULL));
1155
for(plugin *p = plugin_list; p != NULL; p = p->next){
1159
if(p->next == NULL){
1160
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1166
/* Main loop while running plugins exist */
1168
fd_set rfds = rfds_all;
1169
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1170
if(select_ret == -1 and errno != EINTR){
1171
error(0, errno, "select");
1172
exitstatus = EX_OSERR;
1175
/* OK, now either a process completed, or something can be read
1177
for(plugin *proc = plugin_list; proc != NULL;){
1178
/* Is this process completely done? */
1179
if(proc->completed and proc->eof){
1180
/* Only accept the plugin output if it exited cleanly */
1181
if(not WIFEXITED(proc->status)
1182
or WEXITSTATUS(proc->status) != 0){
1183
/* Bad exit by plugin */
1186
if(WIFEXITED(proc->status)){
1187
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1188
" status %d\n", proc->name,
1189
(intmax_t) (proc->pid),
1190
WEXITSTATUS(proc->status));
1191
} else if(WIFSIGNALED(proc->status)){
1192
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1193
" signal %d: %s\n", proc->name,
1194
(intmax_t) (proc->pid),
1195
WTERMSIG(proc->status),
1196
strsignal(WTERMSIG(proc->status)));
1200
/* Remove the plugin */
1201
FD_CLR(proc->fd, &rfds_all);
1203
/* Block signal while modifying process_list */
1204
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1206
&sigchld_action.sa_mask,
1209
error(0, errno, "sigprocmask");
1210
exitstatus = EX_OSERR;
1214
plugin *next_plugin = proc->next;
1218
/* We are done modifying process list, so unblock signal */
1219
ret = (int)(TEMP_FAILURE_RETRY
1220
(sigprocmask(SIG_UNBLOCK,
1221
&sigchld_action.sa_mask, NULL)));
1223
error(0, errno, "sigprocmask");
1224
exitstatus = EX_OSERR;
1228
if(plugin_list == NULL){
1235
/* This process exited nicely, so print its buffer */
1237
bool bret = print_out_password(proc->buffer,
1238
proc->buffer_length);
1240
error(0, errno, "print_out_password");
1241
exitstatus = EX_IOERR;
1246
/* This process has not completed. Does it have any output? */
1247
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1248
/* This process had nothing to say at this time */
1252
/* Before reading, make the process' data buffer large enough */
1253
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1254
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1255
+ (size_t) BUFFER_SIZE);
1256
if(new_buffer == NULL){
1257
error(0, errno, "malloc");
1258
exitstatus = EX_OSERR;
1261
proc->buffer = new_buffer;
1262
proc->buffer_size += BUFFER_SIZE;
1264
/* Read from the process */
1265
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1267
+ proc->buffer_length,
1270
/* Read error from this process; ignore the error */
1278
proc->buffer_length += (size_t) sret;
1286
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1287
and exitstatus != EX_OK)){
1288
/* Fallback if all plugins failed, none are found or an error
1291
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1292
char *passwordbuffer = getpass("Password: ");
1293
size_t len = strlen(passwordbuffer);
1294
/* Strip trailing newline */
1295
if(len > 0 and passwordbuffer[len-1] == '\n'){
1296
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1299
bret = print_out_password(passwordbuffer, len);
1301
error(0, errno, "print_out_password");
1302
exitstatus = EX_IOERR;
1306
/* Restore old signal handler */
1307
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1309
error(0, errno, "sigaction");
1310
exitstatus = EX_OSERR;
1313
if(custom_argv != NULL){
1314
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1326
/* Kill the processes */
1327
for(plugin *p = plugin_list; p != NULL; p = p->next){
1330
ret = kill(p->pid, SIGTERM);
1331
if(ret == -1 and errno != ESRCH){
1332
/* Set-uid proccesses might not get closed */
1333
error(0, errno, "kill");
1338
/* Wait for any remaining child processes to terminate */
1342
if(errno != ECHILD){
1343
error(0, errno, "wait");
1349
free(pluginhelperdir);