52
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strsep, strlen(), strcpy(),
54
#include <string.h> /* strsep, strlen(), asprintf() */
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55
#include <errno.h> /* errno */
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56
#include <argp.h> /* struct argp_option, struct
58
57
argp_state, struct argp,
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58
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
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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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63
sigprocmask(), SIG_BLOCK, SIGCHLD,
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#define BUFFER_SIZE 256
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
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72
const char *argp_program_version = "plugin-runner 1.0";
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73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
typedef struct process{
77
typedef struct plugin{
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char *name; /* can be NULL or any plugin name */
85
/* Variables used for running processes*/
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89
size_t buffer_size;
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size_t buffer_length;
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typedef struct plugin{
87
char *name; /* can be NULL or any plugin name */
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volatile bool completed;
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struct plugin *next;
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static plugin *getplugin(char *name, plugin **plugin_list){
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for (plugin *p = *plugin_list; p != NULL; p = p->next){
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static plugin *plugin_list = NULL;
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/* Gets a existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
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/* Check for exiting plugin with that name */
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for (plugin *p = plugin_list; p != NULL; p = p->next){
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if ((p->name == name)
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or (p->name and name and (strcmp(p->name, name) == 0))){
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109
/* Create a new plugin */
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110
plugin *new_plugin = malloc(sizeof(plugin));
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111
if (new_plugin == NULL){
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new_plugin->name = name;
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char *copy_name = NULL;
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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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127
new_plugin->argv = malloc(sizeof(char *) * 2);
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128
if (new_plugin->argv == NULL){
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new_plugin->argv[0] = name;
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new_plugin->argv[0] = copy_name;
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134
new_plugin->argv[1] = NULL;
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new_plugin->argc = 1;
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new_plugin->disabled = false;
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new_plugin->next = *plugin_list;
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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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/* Append the new plugin to the list */
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*plugin_list = new_plugin;
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plugin_list = new_plugin;
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147
return new_plugin;
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static 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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/* 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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202
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
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process *process_list = NULL;
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/* Mark a process as completed when it exits, and save its exit
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/* Mark processes as completed when they exit, and save their exit
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208
void handle_sigchld(__attribute__((unused)) int sig){
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process *proc = process_list;
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pid_t pid = wait(&status);
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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;
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proc->completed = true;
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plugin *proc = plugin_list;
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pid_t pid = waitpid(-1, &status, WNOHANG);
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/* Only still running child processes */
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if (errno != ECHILD){
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/* No child processes */
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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;
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proc->completed = true;
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/* Prints out a password to stdout */
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bool print_out_password(const char *buffer, size_t length){
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241
if(length>0 and buffer[length-1] == '\n'){
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/* Removes and free a plugin from the plugin list */
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static void free_plugin(plugin *plugin_node){
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for(char **arg = plugin_node->argv; *arg != NULL; arg++){
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free(plugin_node->argv);
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for(char **env = plugin_node->environ; *env != NULL; env++){
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free(plugin_node->environ);
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free(plugin_node->buffer);
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/* Removes the plugin from the singly-linked list */
268
if(plugin_node == plugin_list){
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/* First one - simple */
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plugin_list = plugin_list->next;
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/* Second one or later */
273
for(plugin *p = plugin_list; p != NULL; p = p->next){
274
if(p->next == plugin_node){
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p->next = plugin_node->next;
284
static void free_plugin_list(void){
285
while(plugin_list != NULL){
286
free_plugin(plugin_list);
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290
int main(int argc, char *argv[]){
189
const char *plugindir = "/lib/mandos/plugins.d";
291
char *plugindir = NULL;
292
char *argfile = NULL;
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size_t d_name_len;
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struct dirent *dirst;
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327
{ .name = "global-options", .key = 'g',
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328
.arg = "OPTION[,OPTION[,...]]",
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329
.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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.doc = "Debug mode", .group = 3 },
345
{ .name = "config-file", .key = 129,
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.doc = "Specify a different configuration file", .group = 2 },
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{ .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 },
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{ .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 },
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{ .name = "debug", .key = 132,
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.doc = "Debug mode", .group = 4 },
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error_t parse_opt (int key, char *arg, struct argp_state *state) {
359
error_t parse_opt (int key, char *arg, __attribute__((unused))
360
struct argp_state *state) {
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/* Get the INPUT argument from `argp_parse', which we know is a
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pointer to our plugin list pointer. */
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plugin **plugins = state->input;
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case 'g': /* --global-options */
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if (arg != NULL){
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while((p = strsep(&arg, ",")) != NULL){
253
if(strcmp(p, "") == 0){
256
addargument(getplugin(NULL, plugins), p);
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if(not add_argument(getplugin(NULL), p)){
372
perror("add_argument");
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return ARGP_ERR_UNKNOWN;
378
case 'e': /* --global-envs */
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char *envdef = strdup(arg);
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if(not add_environment(getplugin(NULL), envdef)){
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perror("add_environment");
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case 'o': /* --options-for */
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if (arg != NULL){
262
char *name = strsep(&arg, ":");
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if(strcmp(name, "") == 0){
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char *p_name = strsep(&arg, ":");
395
if(p_name[0] == '\0'){
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char *opt = strsep(&arg, ":");
267
if(strcmp(opt, "") == 0){
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404
while((p = strsep(&opt, ",")) != NULL){
273
if(strcmp(p, "") == 0){
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addargument(getplugin(name, plugins), p);
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if(not add_argument(getplugin(p_name), p)){
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perror("add_argument");
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return ARGP_ERR_UNKNOWN;
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case 'f': /* --envs-for */
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char *envdef = strchr(arg, ':');
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char *p_name = strndup(arg, (size_t) (envdef-arg));
430
if(not add_environment(getplugin(p_name), envdef)){
431
perror("add_environment");
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case 'd': /* --disable */
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if (arg != NULL){
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getplugin(arg, plugins)->disabled = true;
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plugin *p = getplugin(arg);
439
return ARGP_ERR_UNKNOWN;
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case 128: /* --plugin-dir */
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plugindir = strdup(arg);
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if(plugindir == NULL){
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case 129: /* --config-file */
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argfile = strdup(arg);
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case 130: /* --userid */
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uid = (uid_t)strtol(arg, NULL, 10);
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case 131: /* --groupid */
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gid = (gid_t)strtol(arg, NULL, 10);
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case 132: /* --debug */
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465
case ARGP_KEY_ARG:
299
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
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fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
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468
case ARGP_KEY_END:
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plugin *plugin_list = NULL;
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476
struct argp argp = { .options = options, .parser = parse_opt,
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477
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
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.doc = "Mandos plugin runner -- Run plugins" };
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ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
480
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
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if (ret == ARGP_ERR_UNKNOWN){
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fprintf(stderr, "Unknown error while parsing arguments\n");
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exitstatus = EXIT_FAILURE;
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/* This is a mangled argument in the form of
327
"+--option+--other-option=parameter+--yet-another-option", etc */
328
/* Make new argc and argv vars, and call argp_parse() again. */
329
plus_options++; /* skip the first '+' character */
330
const char delims[] = "+";
333
plus_argv = malloc(sizeof(char*) * 2);
334
if(plus_argv == NULL){
487
/* Opens the configfile if aviable */
488
if (argfile == NULL){
489
conffp = fopen(AFILE, "r");
491
conffp = fopen(argfile, "r");
494
char *org_line = NULL;
495
char *p, *arg, *new_arg, *line;
498
const char whitespace_delims[] = " \r\t\f\v\n";
499
const char comment_delim[] = "#";
502
custom_argv = malloc(sizeof(char*) * 2);
503
if(custom_argv == NULL){
335
504
perror("malloc");
336
505
exitstatus = EXIT_FAILURE;
339
plus_argv[0] = argv[0];
342
while((arg = strsep(&plus_options, delims)) != NULL){
344
plus_argv = realloc(plus_argv, sizeof(char *)
345
* ((unsigned int) new_argc + 1));
346
if(plus_argv == NULL){
348
exitstatus = EXIT_FAILURE;
351
plus_argv[new_argc-1] = arg;
352
plus_argv[new_argc] = NULL;
355
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
508
custom_argv[0] = argv[0];
509
custom_argv[1] = NULL;
511
/* for each line in the config file, strip whitespace and ignore
514
sret = getline(&org_line, &size, conffp);
520
arg = strsep(&line, comment_delim);
521
while((p = strsep(&arg, whitespace_delims)) != NULL){
528
exitstatus = EXIT_FAILURE;
534
custom_argv = realloc(custom_argv, sizeof(char *)
535
* ((unsigned int) custom_argc + 1));
536
if(custom_argv == NULL){
538
exitstatus = EXIT_FAILURE;
542
custom_argv[custom_argc-1] = new_arg;
543
custom_argv[custom_argc] = NULL;
548
/* Check for harmful errors and go to fallback. Other errors might
549
not affect opening plugins */
550
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
552
exitstatus = EXIT_FAILURE;
556
/* If there was any arguments from configuration file,
557
pass them to parser as command arguments */
558
if(custom_argv != NULL){
559
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);
356
560
if (ret == ARGP_ERR_UNKNOWN){
357
561
fprintf(stderr, "Unknown error while parsing arguments\n");
358
562
exitstatus = EXIT_FAILURE;
497
plugin *p = getplugin(dirst->d_name, &plugin_list);
499
716
/* Add global arguments to argument list for this plugin */
500
plugin *g = getplugin(NULL, &plugin_list);
501
for(char **a = g->argv + 1; *a != NULL; a++){
717
plugin *g = getplugin(NULL);
719
for(char **a = g->argv + 1; *a != NULL; a++){
720
if(not add_argument(p, *a)){
721
perror("add_argument");
724
/* Add global environment variables */
725
for(char **e = g->environ; *e != NULL; e++){
726
if(not add_environment(p, *e)){
727
perror("add_environment");
732
/* If this plugin has any environment variables, we will call
733
using execve and need to duplicate the environment from this
735
if(p->environ[0] != NULL){
736
for(char **e = environ; *e != NULL; e++){
737
char *copy = strdup(*e);
742
if(not add_environment(p, copy)){
743
perror("add_environment");
506
749
ret = pipe(pipefd);
509
752
exitstatus = EXIT_FAILURE;
755
/* Ask OS to automatic close the pipe on exec */
512
756
ret = set_cloexec_flag(pipefd[0]);
514
758
perror("set_cloexec_flag");
515
759
exitstatus = EXIT_FAILURE;
518
762
ret = set_cloexec_flag(pipefd[1]);
520
764
perror("set_cloexec_flag");
521
765
exitstatus = EXIT_FAILURE;
524
768
/* Block SIGCHLD until process is safely in process list */
525
769
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
527
771
perror("sigprocmask");
528
772
exitstatus = EXIT_FAILURE;
531
775
// Starting a new process to be watched
532
776
pid_t pid = fork();
535
779
exitstatus = EXIT_FAILURE;
539
783
/* this is the child process */
559
803
above and must now close it manually here. */
562
if(execv(filename, p->argv) < 0){
806
if(p->environ[0] == NULL){
807
if(execv(filename, p->argv) < 0){
812
if(execve(filename, p->argv, p->environ) < 0){
820
close(pipefd[1]); /* Close unused write end of pipe */
570
close(pipefd[1]); /* close unused write end of pipe */
571
process *new_process = malloc(sizeof(process));
572
if (new_process == NULL){
822
plugin *new_plugin = getplugin(dirst->d_name);
823
if (new_plugin == NULL){
574
825
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
576
perror("sigprocmask");
827
perror("sigprocmask");
578
829
exitstatus = EXIT_FAILURE;
582
*new_process = (struct process){ .pid = pid,
584
.next = process_list };
586
process_list = new_process;
833
new_plugin->pid = pid;
834
new_plugin->fd = pipefd[0];
587
836
/* Unblock SIGCHLD so signal handler can be run if this process
588
837
has already completed */
589
838
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
591
840
perror("sigprocmask");
592
841
exitstatus = EXIT_FAILURE;
596
FD_SET(new_process->fd, &rfds_all);
598
if (maxfd < new_process->fd){
599
maxfd = new_process->fd;
604
/* Free the plugin list */
605
for(plugin *next; plugin_list != NULL; plugin_list = next){
606
next = plugin_list->next;
607
free(plugin_list->argv);
845
FD_SET(new_plugin->fd, &rfds_all);
847
if (maxfd < new_plugin->fd){
848
maxfd = new_plugin->fd;
614
if (process_list == NULL){
615
fprintf(stderr, "No plugin processes started. Incorrect plugin"
856
for(plugin *p = plugin_list; p != NULL; p = p->next){
861
fprintf(stderr, "No plugin processes started. Incorrect plugin"
867
/* Main loop while running plugins exist */
620
869
fd_set rfds = rfds_all;
621
870
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
622
871
if (select_ret == -1){
623
872
perror("select");
624
873
exitstatus = EXIT_FAILURE;
627
876
/* OK, now either a process completed, or something can be read
628
877
from one of them */
629
for(process *proc = process_list; proc ; proc = proc->next){
878
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
630
879
/* Is this process completely done? */
631
880
if(proc->eof and proc->completed){
632
881
/* Only accept the plugin output if it exited cleanly */
633
882
if(not WIFEXITED(proc->status)
634
883
or WEXITSTATUS(proc->status) != 0){
635
884
/* Bad exit by plugin */
637
887
if(WIFEXITED(proc->status)){
638
888
fprintf(stderr, "Plugin %u exited with status %d\n",
647
897
(unsigned int) (proc->pid));
650
901
/* Remove the plugin */
651
902
FD_CLR(proc->fd, &rfds_all);
652
904
/* Block signal while modifying process_list */
653
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
905
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
655
907
perror("sigprocmask");
656
908
exitstatus = EXIT_FAILURE;
659
/* Delete this process entry from the list */
660
if(process_list == proc){
661
/* First one - simple */
662
process_list = proc->next;
664
/* Second one or later */
665
for(process *p = process_list; p != NULL; p = p->next){
667
p->next = proc->next;
672
912
/* We are done modifying process list, so unblock signal */
673
913
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
676
916
perror("sigprocmask");
680
/* We deleted this process from the list, so we can't go
681
proc->next. Therefore, start over from the beginning of
917
exitstatus = EXIT_FAILURE;
921
if(plugin_list == NULL){
685
927
/* This process exited nicely, so print its buffer */
687
bool bret = print_out_password(proc->buffer, proc->buffer_length);
929
bool bret = print_out_password(proc->buffer,
930
proc->buffer_length);
689
932
perror("print_out_password");
690
933
exitstatus = EXIT_FAILURE;
694
938
/* This process has not completed. Does it have any output? */
695
939
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
696
940
/* This process had nothing to say at this time */