1: /* -*-c-*- */
    2: /*
    3:  * This file is included by eval.c
    4:  */
    5: 
    6: /* safe-level:
    7:    0 - strings from streams/environment/ARGV are tainted (default)
    8:    1 - no dangerous operation by tainted value
    9:    2 - process/file operations prohibited
   10:    3 - all generated objects are tainted
   11:    4 - no global (non-tainted) variable modification/no direct output
   12: */
   13: 
   14: #define SAFE_LEVEL_MAX 4
   15: 
   16: /* $SAFE accessor */
   17: 
   18: int
   19: rb_safe_level(void)
   20: {
   21:     return GET_THREAD()->safe_level;
   22: }
   23: 
   24: void
   25: rb_set_safe_level_force(int safe)
   26: {
   27:     GET_THREAD()->safe_level = safe;
   28: }
   29: 
   30: void
   31: rb_set_safe_level(int level)
   32: {
   33:     rb_thread_t *th = GET_THREAD();
   34: 
   35:     if (level > th->safe_level) {
   36:         if (level > SAFE_LEVEL_MAX) {
   37:             level = SAFE_LEVEL_MAX;
   38:         }
   39:         th->safe_level = level;
   40:     }
   41: }
   42: 
   43: static VALUE
   44: safe_getter(void)
   45: {
   46:     return INT2NUM(rb_safe_level());
   47: }
   48: 
   49: static void
   50: safe_setter(VALUE val)
   51: {
   52:     int level = NUM2INT(val);
   53:     rb_thread_t *th = GET_THREAD();
   54: 
   55:     if (level < th->safe_level) {
   56:         rb_raise(rb_eSecurityError,
   57:                  "tried to downgrade safe level from %d to %d",
   58:                  th->safe_level, level);
   59:     }
   60:     if (level > SAFE_LEVEL_MAX) {
   61:         level = SAFE_LEVEL_MAX;
   62:     }
   63:     th->safe_level = level;
   64: }
   65: 
   66: void
   67: rb_secure(int level)
   68: {
   69:     if (level <= rb_safe_level()) {
   70:         if (rb_frame_callee()) {
   71:             rb_raise(rb_eSecurityError, "Insecure operation `%s' at level %d",
   72:                      rb_id2name(rb_frame_callee()), rb_safe_level());
   73:         }
   74:         else {
   75:             rb_raise(rb_eSecurityError, "Insecure operation at level %d",
   76:                      rb_safe_level());
   77:         }
   78:     }
   79: }
   80: 
   81: void
   82: rb_secure_update(VALUE obj)
   83: {
   84:     if (!OBJ_TAINTED(obj))
   85:         rb_secure(4);
   86: }
   87: 
   88: void
   89: rb_check_safe_obj(VALUE x)
   90: {
   91:     if (rb_safe_level() > 0 && OBJ_TAINTED(x)) {
   92:         if (rb_frame_callee()) {
   93:             rb_raise(rb_eSecurityError, "Insecure operation - %s",
   94:                      rb_id2name(rb_frame_callee()));
   95:         }
   96:         else {
   97:             rb_raise(rb_eSecurityError, "Insecure operation: -r");
   98:         }
   99:     }
  100:     rb_secure(4);
  101: }
  102: 
  103: void
  104: rb_check_safe_str(VALUE x)
  105: {
  106:     rb_check_safe_obj(x);
  107:     if (TYPE(x) != T_STRING) {
  108:         rb_raise(rb_eTypeError, "wrong argument type %s (expected String)",
  109:                  rb_obj_classname(x));
  110:     }
  111: }