/****** uti/sanitize_environment() *****************************************
* NAME
* sanitize_environment() -- remove sensitive variables from the environment before calling programs
*
* SYNOPSIS
* #include "uti/execvlp.h"
* void sanitize_environment(char *env[])
*
* FUNCTION
* Remove variables from the environment which represent a security
* risk when a program is called under a privileged id with an
* environment supplied by the user, such as remote
* communication daemons. (For instance, if the user can get a
* dynamically-linked privileged program run in an ELF environment
* with arbitrary LD_LIBRARY_PATH or LD_PRELOAD, all bets are off.)
*
* SEE ALSO
* qrsh_starter
*******************************************************************************/
void
sanitize_environment (char *env[])
{
int i = 0, j;
regex_t lc_regex;
const char *sharedlib = var_get_sharedlib_path_name ();
/* Valid locale -- see var_unsafe. */
const char *lc_pattern = "^[A-Za-z_]+=[A-Za-z][-A-Za-z0-9_,+@.=]*$";
if (!env) return;
/* We only need to bother if we're privileged in some way. */
if ((geteuid () != SGE_SUPERUSER_UID)
&& (getegid () != SGE_SUPERUSER_GID)
&& (geteuid () == getuid ())
&& (getegid () == getgid ()))
return;
if (regcomp (&lc_regex, lc_pattern, REG_NOSUB | REG_EXTENDED))
exit(1);
while (env[i]) {
/* In an ELF system, sensitive variables include
LD_LIBRARY_PATH, plus variations like LD_LIBRARY_PATH64, and
LD_PRELOAD. For safety, we'll zap anything with an LD_
prefix. (We could test the __ELF__ of the system, but this
is safer.) Similarly check var_get_sharedlib_path_name as a
prefix. */
if ((strncmp (env[i], "LD_", 3) == 0)
/* Known in Tru64, but sudo has it generally */
|| (strncmp (env[i], "_RLD_", 5) == 0)
#ifdef __APPLE__
/* DYLD_{FALLBACK_,}FRAMEWORK_PATH,
{FALLBACK_,}DYLD_LIBRARY_PATH seem to be relevant. */
|| (strncmp (env[i], "DYLD_", 5) == 0)
#elif defined _AIX
|| (strncmp (env[i], "LDR_", 4) == 0)
#elif defined __hpux__
/* _HP_DLDOPTS is loader options; guess a prefix. */
|| (strncmp (env[i], "_HP_DLD", 7) == 0)
#endif
|| (strncmp (env[i], sharedlib, strlen (sharedlib)) == 0)
|| var_unsafe (env[i], lc_regex)) {
/* Shuffle env elements down over the unsafe one. */
for (j=i; env[j]; j++)
env[j] = env[j+1];
} else {
i++;
}
}
regfree (&lc_regex);
return;
}
/****** sgeobj/var/var_list_set_sharedlib_path() ******************************
* NAME
* var_list_set_sharedlib_path -- set shared lib path
*
* SYNOPSIS
* void var_list_set_sharedlib_path(lList **varl);
*
* FUNCTION
* Sets or replaces the shared lib path in the list of variables.
* The SGE shared lib path is always set to the beginning of the
* resulting shared lib path
* (security, see var_get_sharedlib_path_name())
*
* INPUTS
* lList **varl - list of nment variables
*
* SEE ALSO
* sgeobj/var/var_get_sharedlib_path_name()
* sgeobj/var/var_list_set_string()
* sgeobj/var/var_list_set_int()
* sgeobj/var/var_list_set_sge_u32()
******************************************************************************/
void var_list_set_sharedlib_path(lList **varl)
{
char *sharedlib_path;
char *sge_sharedlib_path;
const char *sge_root = sge_get_root_dir(0, NULL, 0, 1);
const char *sharedlib_path_name = var_get_sharedlib_path_name();
lListElem *sharedlib_elem = NULL;
DENTER(TOP_LAYER, "set_sharedlib_path");
/* this is the SGE sharedlib path */
sge_sharedlib_path = sge_malloc(strlen(sge_root) +
strlen("/lib/") + strlen(sge_get_arch()) + 1);
sprintf(sge_sharedlib_path, "%s/lib/%s", sge_root, sge_get_arch());
/* if already in environment: extend by SGE sharedlib path, else set */
sharedlib_elem = lGetElemStr(*varl, VA_variable, sharedlib_path_name);
if(sharedlib_elem != NULL) {
const char *old_value = lGetString(sharedlib_elem, VA_value);
if(old_value && strlen(old_value) > 0) {
DPRINTF(("sharedlib path %s already set:\n", sharedlib_path_name));
sharedlib_path = sge_malloc(strlen(old_value) + 1 +
strlen(sge_sharedlib_path) + 1);
strcpy(sharedlib_path, sge_sharedlib_path);
strcat(sharedlib_path, ":");
strcat(sharedlib_path, old_value);
lSetString(sharedlib_elem, VA_value, sharedlib_path);
sge_free(&sharedlib_path);
} else {
DPRINTF(("overwriting empty sharedlib path %s\n",
sharedlib_path_name));
lSetString(sharedlib_elem, VA_value, sge_sharedlib_path);
}
} else {
DPRINTF(("creating new sharedlib path %s\n", sharedlib_path_name));
sharedlib_elem = lAddElemStr(varl, VA_variable,
sharedlib_path_name, VA_Type);
lSetString(sharedlib_elem, VA_value, sge_sharedlib_path);
}
sge_free(&sge_sharedlib_path);
DEXIT;
}
