342 lines
7.8 KiB
C
342 lines
7.8 KiB
C
|
/******************************************************************************
|
||
|
|
* popen.c
|
||
|
|
*
|
||
|
|
* A safe alternative to popen
|
||
|
|
*
|
||
|
|
* Provides spopen and spclose
|
||
|
|
|
||
|
|
FILE * spopen(const char *);
|
||
|
|
int spclose(FILE *);
|
||
|
|
|
||
|
|
*
|
||
|
|
* Code taken with liitle modification from "Advanced Programming for the Unix
|
||
|
|
* Environment" by W. Richard Stevens
|
||
|
|
*
|
||
|
|
* This is considered safe in that no shell is spawned, and the environment and
|
||
|
|
* path passed to the exec'd program are esstially empty. (popen create a shell
|
||
|
|
* and passes the environment to it).
|
||
|
|
*
|
||
|
|
* $Id: popen.c,v 1.13 2005/09/12 10:31:28 tonvoon Exp $
|
||
|
|
*
|
||
|
|
******************************************************************************/
|
||
|
|
|
||
|
|
#include "common.h"
|
||
|
|
|
||
|
|
/* extern so plugin has pid to kill exec'd process on timeouts */
|
||
|
|
extern int timeout_interval;
|
||
|
|
extern pid_t *childpid;
|
||
|
|
extern int *child_stderr_array;
|
||
|
|
extern FILE *child_process;
|
||
|
|
|
||
|
|
FILE *spopen (const char *);
|
||
|
|
int spclose (FILE *);
|
||
|
|
#ifdef REDHAT_SPOPEN_ERROR
|
||
|
|
RETSIGTYPE popen_sigchld_handler (int);
|
||
|
|
#endif
|
||
|
|
RETSIGTYPE popen_timeout_alarm_handler (int);
|
||
|
|
|
||
|
|
#include <stdarg.h> /* ANSI C header file */
|
||
|
|
#include <fcntl.h>
|
||
|
|
|
||
|
|
#include <limits.h>
|
||
|
|
#include <sys/resource.h>
|
||
|
|
|
||
|
|
#ifdef HAVE_SYS_WAIT_H
|
||
|
|
#include <sys/wait.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef WEXITSTATUS
|
||
|
|
# define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef WIFEXITED
|
||
|
|
# define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* 4.3BSD Reno <signal.h> doesn't define SIG_ERR */
|
||
|
|
#if defined(SIG_IGN) && !defined(SIG_ERR)
|
||
|
|
#define SIG_ERR ((Sigfunc *)-1)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define min(a,b) ((a) < (b) ? (a) : (b))
|
||
|
|
#define max(a,b) ((a) > (b) ? (a) : (b))
|
||
|
|
int open_max (void); /* {Prog openmax} */
|
||
|
|
static void err_sys (const char *, ...) __attribute__((noreturn,format(printf, 1, 2)));
|
||
|
|
char *rtrim (char *, const char *);
|
||
|
|
|
||
|
|
char *pname = NULL; /* caller can set this from argv[0] */
|
||
|
|
|
||
|
|
/*int *childerr = NULL;*//* ptr to array allocated at run-time */
|
||
|
|
/*extern pid_t *childpid = NULL; *//* ptr to array allocated at run-time */
|
||
|
|
static int maxfd; /* from our open_max(), {Prog openmax} */
|
||
|
|
|
||
|
|
#ifdef REDHAT_SPOPEN_ERROR
|
||
|
|
static volatile int childtermd = 0;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
FILE *
|
||
|
|
spopen (const char *cmdstring)
|
||
|
|
{
|
||
|
|
char *env[2];
|
||
|
|
char *cmd = NULL;
|
||
|
|
char **argv = NULL;
|
||
|
|
char *str;
|
||
|
|
int argc;
|
||
|
|
|
||
|
|
int i = 0, pfd[2], pfderr[2];
|
||
|
|
pid_t pid;
|
||
|
|
|
||
|
|
#ifdef RLIMIT_CORE
|
||
|
|
/* do not leave core files */
|
||
|
|
struct rlimit limit;
|
||
|
|
getrlimit (RLIMIT_CORE, &limit);
|
||
|
|
limit.rlim_cur = 0;
|
||
|
|
setrlimit (RLIMIT_CORE, &limit);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
env[0] = strdup("LC_ALL=C");
|
||
|
|
env[1] = '\0';
|
||
|
|
|
||
|
|
/* if no command was passed, return with no error */
|
||
|
|
if (cmdstring == NULL)
|
||
|
|
return (NULL);
|
||
|
|
|
||
|
|
/* make copy of command string so strtok() doesn't silently modify it */
|
||
|
|
/* (the calling program may want to access it later) */
|
||
|
|
cmd = malloc (strlen (cmdstring) + 1);
|
||
|
|
if (cmd == NULL)
|
||
|
|
return NULL;
|
||
|
|
strcpy (cmd, cmdstring);
|
||
|
|
|
||
|
|
/* This is not a shell, so we don't handle "???" */
|
||
|
|
if (strstr (cmdstring, "\""))
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
/* allow single quotes, but only if non-whitesapce doesn't occur on both sides */
|
||
|
|
if (strstr (cmdstring, " ' ") || strstr (cmdstring, "'''"))
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
/* there cannot be more args than characters */
|
||
|
|
argc = strlen (cmdstring) + 1; /* add 1 for NULL termination */
|
||
|
|
argv = malloc (sizeof(char*)*argc);
|
||
|
|
|
||
|
|
if (argv == NULL) {
|
||
|
|
printf (_("Could not malloc argv array in popen()\n"));
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* loop to get arguments to command */
|
||
|
|
while (cmd) {
|
||
|
|
str = cmd;
|
||
|
|
str += strspn (str, " \t\r\n"); /* trim any leading whitespace */
|
||
|
|
|
||
|
|
if (i >= argc - 2) {
|
||
|
|
printf (_("CRITICAL - You need more args!!!\n"));
|
||
|
|
return (NULL);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (strstr (str, "'") == str) { /* handle SIMPLE quoted strings */
|
||
|
|
str++;
|
||
|
|
if (!strstr (str, "'"))
|
||
|
|
return NULL; /* balanced? */
|
||
|
|
cmd = 1 + strstr (str, "'");
|
||
|
|
str[strcspn (str, "'")] = 0;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if (strpbrk (str, " \t\r\n")) {
|
||
|
|
cmd = 1 + strpbrk (str, " \t\r\n");
|
||
|
|
str[strcspn (str, " \t\r\n")] = 0;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
cmd = NULL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (cmd && strlen (cmd) == strspn (cmd, " \t\r\n"))
|
||
|
|
cmd = NULL;
|
||
|
|
|
||
|
|
argv[i++] = str;
|
||
|
|
|
||
|
|
}
|
||
|
|
argv[i] = NULL;
|
||
|
|
|
||
|
|
if (childpid == NULL) { /* first time through */
|
||
|
|
maxfd = open_max (); /* allocate zeroed out array for child pids */
|
||
|
|
if ((childpid = calloc ((size_t)maxfd, sizeof (pid_t))) == NULL)
|
||
|
|
return (NULL);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (child_stderr_array == NULL) { /* first time through */
|
||
|
|
maxfd = open_max (); /* allocate zeroed out array for child pids */
|
||
|
|
if ((child_stderr_array = calloc ((size_t)maxfd, sizeof (int))) == NULL)
|
||
|
|
return (NULL);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (pipe (pfd) < 0)
|
||
|
|
return (NULL); /* errno set by pipe() */
|
||
|
|
|
||
|
|
if (pipe (pfderr) < 0)
|
||
|
|
return (NULL); /* errno set by pipe() */
|
||
|
|
|
||
|
|
#ifdef REDHAT_SPOPEN_ERROR
|
||
|
|
if (signal (SIGCHLD, popen_sigchld_handler) == SIG_ERR) {
|
||
|
|
usage4 (_("Cannot catch SIGCHLD"));
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if ((pid = fork ()) < 0)
|
||
|
|
return (NULL); /* errno set by fork() */
|
||
|
|
else if (pid == 0) { /* child */
|
||
|
|
close (pfd[0]);
|
||
|
|
if (pfd[1] != STDOUT_FILENO) {
|
||
|
|
dup2 (pfd[1], STDOUT_FILENO);
|
||
|
|
close (pfd[1]);
|
||
|
|
}
|
||
|
|
close (pfderr[0]);
|
||
|
|
if (pfderr[1] != STDERR_FILENO) {
|
||
|
|
dup2 (pfderr[1], STDERR_FILENO);
|
||
|
|
close (pfderr[1]);
|
||
|
|
}
|
||
|
|
/* close all descriptors in childpid[] */
|
||
|
|
for (i = 0; i < maxfd; i++)
|
||
|
|
if (childpid[i] > 0)
|
||
|
|
close (i);
|
||
|
|
|
||
|
|
execve (argv[0], argv, env);
|
||
|
|
_exit (0);
|
||
|
|
}
|
||
|
|
|
||
|
|
close (pfd[1]); /* parent */
|
||
|
|
if ((child_process = fdopen (pfd[0], "r")) == NULL)
|
||
|
|
return (NULL);
|
||
|
|
close (pfderr[1]);
|
||
|
|
|
||
|
|
childpid[fileno (child_process)] = pid; /* remember child pid for this fd */
|
||
|
|
child_stderr_array[fileno (child_process)] = pfderr[0]; /* remember STDERR */
|
||
|
|
return (child_process);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
spclose (FILE * fp)
|
||
|
|
{
|
||
|
|
int fd, status;
|
||
|
|
pid_t pid;
|
||
|
|
|
||
|
|
if (childpid == NULL)
|
||
|
|
return (1); /* popen() has never been called */
|
||
|
|
|
||
|
|
fd = fileno (fp);
|
||
|
|
if ((pid = childpid[fd]) == 0)
|
||
|
|
return (1); /* fp wasn't opened by popen() */
|
||
|
|
|
||
|
|
childpid[fd] = 0;
|
||
|
|
if (fclose (fp) == EOF)
|
||
|
|
return (1);
|
||
|
|
|
||
|
|
#ifdef REDHAT_SPOPEN_ERROR
|
||
|
|
while (!childtermd); /* wait until SIGCHLD */
|
||
|
|
#endif
|
||
|
|
|
||
|
|
while (waitpid (pid, &status, 0) < 0)
|
||
|
|
if (errno != EINTR)
|
||
|
|
return (1); /* error other than EINTR from waitpid() */
|
||
|
|
|
||
|
|
if (WIFEXITED (status))
|
||
|
|
return (WEXITSTATUS (status)); /* return child's termination status */
|
||
|
|
|
||
|
|
return (1);
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef OPEN_MAX
|
||
|
|
static int openmax = OPEN_MAX;
|
||
|
|
#else
|
||
|
|
static int openmax = 0;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define OPEN_MAX_GUESS 256 /* if OPEN_MAX is indeterminate */
|
||
|
|
/* no guarantee this is adequate */
|
||
|
|
|
||
|
|
#ifdef REDHAT_SPOPEN_ERROR
|
||
|
|
RETSIGTYPE
|
||
|
|
popen_sigchld_handler (int signo)
|
||
|
|
{
|
||
|
|
if (signo == SIGCHLD)
|
||
|
|
childtermd = 1;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
RETSIGTYPE
|
||
|
|
popen_timeout_alarm_handler (int signo)
|
||
|
|
{
|
||
|
|
int fh;
|
||
|
|
if (signo == SIGALRM) {
|
||
|
|
fh=fileno (child_process);
|
||
|
|
if(fh >= 0){
|
||
|
|
kill (childpid[fh], SIGKILL);
|
||
|
|
}
|
||
|
|
printf (_("CRITICAL - Plugin timed out after %d seconds\n"),
|
||
|
|
timeout_interval);
|
||
|
|
exit (STATE_CRITICAL);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int
|
||
|
|
open_max (void)
|
||
|
|
{
|
||
|
|
if (openmax == 0) { /* first time through */
|
||
|
|
errno = 0;
|
||
|
|
if ((openmax = sysconf (_SC_OPEN_MAX)) < 0) {
|
||
|
|
if (errno == 0)
|
||
|
|
openmax = OPEN_MAX_GUESS; /* it's indeterminate */
|
||
|
|
else
|
||
|
|
err_sys (_("sysconf error for _SC_OPEN_MAX"));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return (openmax);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/* Fatal error related to a system call.
|
||
|
|
* Print a message and die. */
|
||
|
|
|
||
|
|
#define MAXLINE 2048
|
||
|
|
static void
|
||
|
|
err_sys (const char *fmt, ...)
|
||
|
|
{
|
||
|
|
int errnoflag = 1;
|
||
|
|
int errno_save;
|
||
|
|
char buf[MAXLINE];
|
||
|
|
|
||
|
|
va_list ap;
|
||
|
|
|
||
|
|
va_start (ap, fmt);
|
||
|
|
/* err_doit (1, fmt, ap); */
|
||
|
|
errno_save = errno; /* value caller might want printed */
|
||
|
|
vsprintf (buf, fmt, ap);
|
||
|
|
if (errnoflag)
|
||
|
|
sprintf (buf + strlen (buf), ": %s", strerror (errno_save));
|
||
|
|
strcat (buf, "\n");
|
||
|
|
fflush (stdout); /* in case stdout and stderr are the same */
|
||
|
|
fputs (buf, stderr);
|
||
|
|
fflush (NULL); /* flushes all stdio output streams */
|
||
|
|
va_end (ap);
|
||
|
|
exit (1);
|
||
|
|
}
|
||
|
|
|
||
|
|
char *
|
||
|
|
rtrim (char *str, const char *tok)
|
||
|
|
{
|
||
|
|
int i = 0;
|
||
|
|
int j = sizeof (str);
|
||
|
|
|
||
|
|
while (str != NULL && i < j) {
|
||
|
|
if (*(str + i) == *tok) {
|
||
|
|
sprintf (str + i, "%s", "\0");
|
||
|
|
return str;
|
||
|
|
}
|
||
|
|
i++;
|
||
|
|
}
|
||
|
|
return str;
|
||
|
|
}
|