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21
* Contact the authors at <mandos@fukt.bsnet.se>.
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
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EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
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fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
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WEXITSTATUS(), wait(), pid_t,
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uid_t, gid_t, getuid(), getgid(),
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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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#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
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#include <stdio.h> /* popen(), fileno(), fprintf(),
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stderr, STDOUT_FILENO */
42
28
#include <iso646.h> /* and, or, not */
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#include <sys/types.h> /* DIR, opendir(), stat(),
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struct stat, waitpid(),
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WIFEXITED(), WEXITSTATUS(),
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#include <sys/wait.h> /* wait() */
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34
#include <dirent.h> /* DIR, struct dirent, opendir(),
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readdir(), closedir(), dirfd() */
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readdir(), closedir() */
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#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
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#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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fcntl(), setuid(), setgid(),
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F_GETFD, F_SETFD, FD_CLOEXEC,
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access(), pipe(), fork(), close()
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dup2, STDOUT_FILENO, _exit(),
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execv(), write(), read(),
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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#include <string.h> /* strsep, strlen(), asprintf() */
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#include <fcntl.h> /* fcntl() */
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#include <stddef.h> /* NULL */
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#include <stdlib.h> /* EXIT_FAILURE */
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#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
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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(),
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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, error_t */
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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() */
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#include <errno.h> /* errno, EBADF */
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#define BUFFER_SIZE 256
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#define ARGFILE "/conf/conf.d/mandos/plugin-runner.conf"
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const char *argp_program_version = "plugin-runner 1.0";
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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#include <argp.h> /* struct argp_option,
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struct argp_state, struct argp,
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/* Create a new plugin */
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plugin *new_plugin = malloc(sizeof(plugin));
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if (new_plugin == NULL){
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char *copy_name = strdup(name);
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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->name = name;
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new_plugin->argv = malloc(sizeof(char *) * 2);
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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[0] = name;
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new_plugin->argv[1] = NULL;
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new_plugin->environ = malloc(sizeof(char *));
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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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new_plugin->disabled = false;
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new_plugin->next = *plugin_list;
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/* Append the new plugin to the list */
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*plugin_list = new_plugin;
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return new_plugin;
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/* Helper function for add_argument and add_environment */
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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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*array = realloc(*array, sizeof(char *)
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* (size_t) ((*len) + 2));
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/* Make a copy of the new string */
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char *copy = strdup(new);
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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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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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static bool add_environment(plugin *p, const char *def){
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return add_to_char_array(def, &(p->environ), &(p->envc));
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void addargument(plugin *p, char *arg){
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p->argv[p->argc] = arg;
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p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
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if (p->argv == NULL){
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p->argv[p->argc] = NULL;
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* Based on the example in the GNU LibC manual chapter 13.13 "File
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117
* Descriptor Flags".
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* *Note File Descriptor Flags:(libc)Descriptor Flags.
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static int set_cloexec_flag(int fd)
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int set_cloexec_flag(int fd)
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int ret = fcntl(fd, F_GETFD, 0);
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/* If reading the flags failed, return error indication now. */
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proc->completed = true;
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bool print_out_password(const char *buffer, size_t length){
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if(length>0 and buffer[length-1] == '\n'){
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for(size_t written = 0; written < length; written += (size_t)ret){
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ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
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char **add_to_argv(char **argv, int *argc, char *arg){
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argv = malloc(sizeof(char*) * 2);
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argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
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argv = realloc(argv, sizeof(char *)
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* ((unsigned int) *argc + 1));
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static void free_plugin_list(plugin *plugin_list){
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for(plugin *next = plugin_list; plugin_list != NULL; plugin_list = next){
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next = plugin_list->next;
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free(plugin_list->name);
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for(char **arg = plugin_list->argv; *arg != NULL; arg++){
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free(plugin_list->argv);
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for(char **env = plugin_list->environ; *env != NULL; env++){
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free(plugin_list->environ);
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int main(int argc, char *argv[]){
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const char *plugindir = "/lib/mandos/plugins.d";
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const char *argfile = ARGFILE;
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const char *plugindir = "/conf/conf.d/mandos/plugins.d";
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size_t d_name_len;
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struct dirent *dirst;
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int ret, maxfd = 0;
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bool debug = false;
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int exitstatus = EXIT_SUCCESS;
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struct sigaction old_sigchld_action;
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struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
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.sa_flags = SA_NOCLDSTOP };
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char **custom_argv = NULL;
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/* Establish a signal handler */
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struct sigaction old_sigchld_action,
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sigchld_action = { .sa_handler = handle_sigchld,
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.sa_flags = SA_NOCLDSTOP };
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sigemptyset(&sigchld_action.sa_mask);
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ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
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perror("sigaddset");
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exitstatus = EXIT_FAILURE;
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ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
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perror("sigaction");
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exitstatus = EXIT_FAILURE;
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/* The options we understand. */
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{ .name = "global-options", .key = 'g',
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.arg = "OPTION[,OPTION[,...]]",
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.doc = "Options passed to all plugins" },
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{ .name = "global-envs", .key = 'e',
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.doc = "Environment variable passed to all plugins" },
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{ .name = "options-for", .key = 'o',
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.arg = "PLUGIN:OPTION[,OPTION[,...]]",
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.doc = "Options passed only to specified plugin" },
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{ .name = "envs-for", .key = 'f',
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.arg = "PLUGIN:ENV=value",
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.doc = "Environment variable passed to specified plugin" },
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{ .name = "disable", .key = 'd',
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.doc = "Disable a specific plugin", .group = 1 },
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{ .name = "plugin-dir", .key = 128,
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.arg = "DIRECTORY",
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.doc = "Specify a different plugin directory", .group = 2 },
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{ .name = "userid", .key = 129,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 2 },
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{ .name = "groupid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 2 },
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{ .name = "debug", .key = 131,
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{ .name = "debug", .key = 129,
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.doc = "Debug mode", .group = 3 },
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if (arg != NULL){
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while((p = strsep(&arg, ",")) != NULL){
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if(not add_argument(getplugin(NULL, plugins), p)){
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perror("add_argument");
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return ARGP_ERR_UNKNOWN;
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char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
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perror("add_environment");
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char *p = strtok(arg, ",");
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addargument(getplugin(NULL, plugins), p);
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p = strtok(NULL, ",");
370
216
if (arg != NULL){
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char *p_name = strsep(&arg, ":");
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if(p_name[0] == '\0'){
375
char *opt = strsep(&arg, ":");
381
while((p = strsep(&opt, ",")) != NULL){
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if(not add_argument(getplugin(p_name, plugins), p)){
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perror("add_argument");
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return ARGP_ERR_UNKNOWN;
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char *envdef = strchr(arg, ':');
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char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
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perror("add_environment");
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char *name = strtok(arg, ":");
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char *p = strtok(NULL, ":");
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addargument(getplugin(name, plugins), p);
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p = strtok(NULL, ",");
413
229
if (arg != NULL){
414
plugin *p = getplugin(arg, plugins);
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return ARGP_ERR_UNKNOWN;
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getplugin(arg, plugins)->disabled = true;
425
uid = (uid_t)strtol(arg, NULL, 10);
428
gid = (gid_t)strtol(arg, NULL, 10);
433
239
case ARGP_KEY_ARG:
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fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
436
242
case ARGP_KEY_END:
444
250
plugin *plugin_list = NULL;
446
252
struct argp argp = { .options = options, .parser = parse_opt,
447
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
448
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.doc = "Mandos plugin runner -- Run plugins" };
450
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
451
if (ret == ARGP_ERR_UNKNOWN){
452
fprintf(stderr, "Unknown error while parsing arguments\n");
453
exitstatus = EXIT_FAILURE;
457
conffp = fopen(argfile, "r");
459
char *org_line = NULL;
460
char *p, *arg, *new_arg, *line;
463
const char whitespace_delims[] = " \r\t\f\v\n";
464
const char comment_delim[] = "#";
467
sret = getline(&org_line, &size, conffp);
473
arg = strsep(&line, comment_delim);
474
while((p = strsep(&arg, whitespace_delims)) != NULL){
479
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
480
if (custom_argv == NULL){
481
perror("add_to_argv");
482
exitstatus = EXIT_FAILURE;
489
/* Check for harmful errors and go to fallback. Other errors might
490
not affect opening plugins */
491
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
493
exitstatus = EXIT_FAILURE;
498
if(custom_argv != NULL){
499
custom_argv[0] = argv[0];
500
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
501
if (ret == ARGP_ERR_UNKNOWN){
502
fprintf(stderr, "Unknown error while parsing arguments\n");
503
exitstatus = EXIT_FAILURE;
256
argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
509
259
for(plugin *p = plugin_list; p != NULL; p=p->next){
373
plugin *p = getplugin(dirst->d_name, &plugin_list);
651
375
/* Add global arguments to argument list for this plugin */
652
376
plugin *g = getplugin(NULL, &plugin_list);
654
for(char **a = g->argv + 1; *a != NULL; a++){
655
if(not add_argument(p, *a)){
656
perror("add_argument");
659
/* Add global environment variables */
660
for(char **e = g->environ; *e != NULL; e++){
661
if(not add_environment(p, *e)){
662
perror("add_environment");
667
/* If this plugin has any environment variables, we will call
668
using execve and need to duplicate the environment from this
670
if(p->environ[0] != NULL){
671
for(char **e = environ; *e != NULL; e++){
672
char *copy = strdup(*e);
677
if(not add_environment(p, copy)){
678
perror("add_environment");
377
for(char **a = g->argv + 1; *a != NULL; a++){
684
382
ret = pipe(pipefd);
687
385
exitstatus = EXIT_FAILURE;
690
388
ret = set_cloexec_flag(pipefd[0]);
692
390
perror("set_cloexec_flag");
693
391
exitstatus = EXIT_FAILURE;
696
394
ret = set_cloexec_flag(pipefd[1]);
698
396
perror("set_cloexec_flag");
699
397
exitstatus = EXIT_FAILURE;
702
400
/* Block SIGCHLD until process is safely in process list */
703
401
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
705
403
perror("sigprocmask");
706
404
exitstatus = EXIT_FAILURE;
709
407
// Starting a new process to be watched
710
408
pid_t pid = fork();
713
exitstatus = EXIT_FAILURE;
717
410
/* this is the child process */
718
411
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
815
501
/* Bad exit by plugin */
817
503
if(WIFEXITED(proc->status)){
818
fprintf(stderr, "Plugin %u exited with status %d\n",
819
(unsigned int) (proc->pid),
820
WEXITSTATUS(proc->status));
504
fprintf(stderr, "Plugin %d exited with status %d\n",
505
proc->pid, WEXITSTATUS(proc->status));
821
506
} else if(WIFSIGNALED(proc->status)) {
822
fprintf(stderr, "Plugin %u killed by signal %d\n",
823
(unsigned int) (proc->pid),
824
WTERMSIG(proc->status));
507
fprintf(stderr, "Plugin %d killed by signal %d\n",
508
proc->pid, WTERMSIG(proc->status));
825
509
} else if(WCOREDUMP(proc->status)){
826
fprintf(stderr, "Plugin %d dumped core\n",
827
(unsigned int) (proc->pid));
510
fprintf(stderr, "Plugin %d dumped core\n", proc->pid);
830
513
/* Remove the plugin */
909
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
910
/* Fallback if all plugins failed, none are found or an error occured */
912
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
913
char *passwordbuffer = getpass("Password: ");
914
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
916
perror("print_out_password");
917
exitstatus = EXIT_FAILURE;
594
if(process_list == NULL){
595
fprintf(stderr, "All plugin processes failed, exiting\n");
596
exitstatus = EXIT_FAILURE;
921
600
/* Restore old signal handler */
922
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
925
exitstatus = EXIT_FAILURE;
928
if(custom_argv != NULL){
929
for(char **arg = custom_argv; *arg != NULL; arg++){
934
free_plugin_list(plugin_list);
601
sigaction(SIGCHLD, &old_sigchld_action, NULL);
603
/* Free the plugin list */
604
for(plugin *next; plugin_list != NULL; plugin_list = next){
605
next = plugin_list->next;
606
free(plugin_list->argv);