/mandos/trunk : revision 379

1

/* -*- coding: utf-8 -*- */

1

/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */

2

/*

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* Mandos plugin runner - Run Mandos plugins

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*

38

#include <sys/select.h> /* fd_set, select(), FD_ZERO(),

39

FD_SET(), FD_ISSET(), FD_CLR */

40

#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),

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WEXITSTATUS() */

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WEXITSTATUS(), WTERMSIG(),

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WCOREDUMP() */

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#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */

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#include <iso646.h> /* and, or, not */

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#include <dirent.h> /* DIR, struct dirent, opendir(),

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close() */

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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,

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FD_CLOEXEC */

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#include <string.h> /* strsep, strlen(), asprintf() */

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#include <string.h> /* strsep, strlen(), asprintf(),

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strsignal() */

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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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}

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}

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/* Create a new plugin */

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plugin *new_plugin = malloc(sizeof(plugin));

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plugin *new_plugin = NULL;

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do {

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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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return NULL;

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}

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char *copy_name = NULL;

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if(name != NULL){

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copy_name = strdup(name);

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do {

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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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free(new_plugin);

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return NULL;

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.disabled = false,

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.next = plugin_list };

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new_plugin->argv = malloc(sizeof(char *) * 2);

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do {

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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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free(copy_name);

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free(new_plugin);

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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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do {

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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(copy_name);

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free(new_plugin->argv);

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164

static bool add_to_char_array(const char *new, char ***array,

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int *len){

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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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do {

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*array = realloc(*array, sizeof(char *)

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* (size_t) ((*len) + 2));

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} while(*array == NULL and errno == EINTR);

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/* Malloc check */

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if(*array == NULL){

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return false;

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}

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/* Make a copy of the new string */

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char *copy = strdup(new);

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char *copy;

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do {

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copy = strdup(new);

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} while(copy == NULL and errno == EINTR);

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if(copy == NULL){

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return false;

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}

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if(strncmp(*e, def, namelen + 1) == 0){

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/* It already exists */

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if(replace){

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char *new = realloc(*e, strlen(def) + 1);

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char *new;

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do {

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new = realloc(*e, strlen(def) + 1);

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} while(new == NULL and errno == EINTR);

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if(new == NULL){

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return false;

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}

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/*

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* Based on the example in the GNU LibC manual chapter 13.13 "File

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* Descriptor Flags".

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* *Note File Descriptor Flags:(libc)Descriptor Flags.

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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |

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*/

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static int set_cloexec_flag(int fd){

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int ret = fcntl(fd, F_GETFD, 0);

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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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if(ret < 0){

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return ret;

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}

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/* Store modified flag word in the descriptor. */

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return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);

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return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,

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ret | FD_CLOEXEC));

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}

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fd_set rfds_all;

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int ret, maxfd = 0;

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ssize_t sret;

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intmax_t tmpmax;

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uid_t uid = 65534;

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gid_t gid = 65534;

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bool debug = false;

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error_t parse_opt(int key, char *arg, __attribute__((unused))

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struct argp_state *state){

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char *tmp;

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switch(key){

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char *tmp;

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intmax_t tmpmax;

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case 'g': /* --global-options */

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if(arg != NULL){

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char *plugin_option;

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plugindir = strdup(arg);

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if(plugindir == NULL){

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perror("strdup");

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}

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}

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break;

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case 129: /* --config-file */

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/* This is already done by parse_opt_config_file() */

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if(argfile == NULL){

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perror("strdup");

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}

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break;

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break;

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case 130: /* --userid */

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case 131: /* --groupid */

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case 132: /* --debug */

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conffp = fopen(AFILE, "r");

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} else {

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conffp = fopen(argfile, "r");

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}

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}

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if(conffp != NULL){

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char *org_line = NULL;

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char *p, *arg, *new_arg, *line;

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goto fallback;

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}

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custom_argv[custom_argc-1] = new_arg;

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custom_argv[custom_argc] = NULL;

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custom_argv[custom_argc] = NULL;

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}

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}

638

do {

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ret = fclose(conffp);

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} while(ret == EOF and errno == EINTR);

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if(ret == EOF){

642

perror("fclose");

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exitstatus = EXIT_FAILURE;

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goto fallback;

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}

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free(org_line);

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} else {

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/* Check for harmful errors and go to fallback. Other errors might

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/* Read and execute any executable in the plugin directory*/

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while(true){

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dirst = readdir(dir);

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do {

731

dirst = readdir(dir);

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} while(dirst == NULL and errno == EINTR);

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/* All directory entries have been processed */

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if(dirst == NULL){

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789

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char *filename;

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791

if(plugindir == NULL){

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ret = asprintf(&filename, PDIR "/%s", dirst->d_name);

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ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",

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dirst->d_name));

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} else {

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ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);

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ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",

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plugindir,

797

dirst->d_name));

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}

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if(ret < 0){

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perror("asprintf");

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continue;

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}

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ret = stat(filename, &st);

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ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));

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if(ret == -1){

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perror("stat");

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free(filename);

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}

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/* Ignore non-executable files */

779

if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){

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if(not S_ISREG(st.st_mode)

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or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){

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if(debug){

781

815

fprintf(stderr, "Ignoring plugin dir entry \"%s\""

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816

" with bad type or mode\n", filename);

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}

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int pipefd[2];

831

ret = pipe(pipefd);

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ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));

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if(ret == -1){

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perror("pipe");

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exitstatus = EXIT_FAILURE;

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goto fallback;

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}

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/* Block SIGCHLD until process is safely in process list */

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ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);

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ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,

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&sigchld_action.sa_mask,

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NULL));

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if(ret < 0){

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perror("sigprocmask");

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890

exitstatus = EXIT_FAILURE;

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goto fallback;

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}

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/* Starting a new process to be watched */

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pid_t pid = fork();

894

pid_t pid;

895

do {

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pid = fork();

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} while(pid == -1 and errno == EINTR);

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if(pid == -1){

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899

perror("fork");

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exitstatus = EXIT_FAILURE;

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/* no return */

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}

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/* Parent process */

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close(pipefd[1]); /* Close unused write end of pipe */

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TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of

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pipe */

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free(filename);

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plugin *new_plugin = getplugin(dirst->d_name);

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if(new_plugin == NULL){

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perror("getplugin");

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ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);

947

ret = (int)(TEMP_FAILURE_RETRY

948

(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

949

NULL)));

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if(ret < 0){

909

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perror("sigprocmask");

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952

}

917

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918

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/* Unblock SIGCHLD so signal handler can be run if this process

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has already completed */

920

ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);

962

ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

963

&sigchld_action.sa_mask,

964

NULL));

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if(ret < 0){

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966

perror("sigprocmask");

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exitstatus = EXIT_FAILURE;

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968

goto fallback;

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969

}

926

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927

FD_SET(new_plugin->fd, &rfds_all);

971

FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from

972

-Wconversion */

928

973

929

974

if(maxfd < new_plugin->fd){

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975

maxfd = new_plugin->fd;

931

976

}

932

977

}

933

978

934

closedir(dir);

979

TEMP_FAILURE_RETRY(closedir(dir));

935

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dir = NULL;

936

981

free_plugin(getplugin(NULL));

937

982

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995

while(plugin_list){

951

996

fd_set rfds = rfds_all;

952

997

int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);

953

if(select_ret == -1){

998

if(select_ret == -1 and errno != EINTR){

954

999

perror("select");

955

1000

exitstatus = EXIT_FAILURE;

956

1001

goto fallback;

973

1018

WEXITSTATUS(proc->status));

974

1019

} else if(WIFSIGNALED(proc->status)){

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1020

fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"

976

" signal %d\n", proc->name,

1021

" signal %d: %s\n", proc->name,

977

1022

(intmax_t) (proc->pid),

978

WTERMSIG(proc->status));

1023

WTERMSIG(proc->status),

1024

strsignal(WTERMSIG(proc->status)));

979

1025

} else if(WCOREDUMP(proc->status)){

980

1026

fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"

981

1027

" core\n", proc->name, (intmax_t) (proc->pid));

983

1029

}

984

1030

985

1031

/* Remove the plugin */

986

FD_CLR(proc->fd, &rfds_all);

1032

FD_CLR(proc->fd, &rfds_all); /* Spurious warning from

1033

-Wconversion */

987

1034

988

1035

/* Block signal while modifying process_list */

989

ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);

1036

ret = (int)TEMP_FAILURE_RETRY(sigprocmask

1037

(SIG_BLOCK,

1038

&sigchld_action.sa_mask,

1039

NULL));

990

1040

if(ret < 0){

991

1041

perror("sigprocmask");

992

1042

exitstatus = EXIT_FAILURE;

998

1048

proc = next_plugin;

999

1049

1000

1050

/* We are done modifying process list, so unblock signal */

1001

ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

1002

NULL);

1051

ret = (int)(TEMP_FAILURE_RETRY

1052

(sigprocmask(SIG_UNBLOCK,

1053

&sigchld_action.sa_mask, NULL)));

1003

1054

if(ret < 0){

1004

1055

perror("sigprocmask");

1005

1056

exitstatus = EXIT_FAILURE;

1025

1076

}

1026

1077

1027

1078

/* This process has not completed. Does it have any output? */

1028

if(proc->eof or not FD_ISSET(proc->fd, &rfds)){

1079

if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious

1080

warning from

1081

-Wconversion */

1029

1082

/* This process had nothing to say at this time */

1030

1083

proc = proc->next;

1031

1084

continue;

1042

1095

proc->buffer_size += BUFFER_SIZE;

1043

1096

}

1044

1097

/* Read from the process */

1045

sret = read(proc->fd, proc->buffer + proc->buffer_length,

1046

BUFFER_SIZE);

1098

sret = TEMP_FAILURE_RETRY(read(proc->fd,

1099

proc->buffer

1100

+ proc->buffer_length,

1101

BUFFER_SIZE));

1047

1102

if(sret < 0){

1048

1103

/* Read error from this process; ignore the error */

1049

1104

proc = proc->next;

1111

1166

}

1112

1167

1113

1168

/* Wait for any remaining child processes to terminate */

1114

do{

1169

do {

1115

1170

ret = wait(NULL);

1116

1171

} while(ret >= 0);

1117

1172

if(errno != ECHILD){