handler for function_exists

3 files changed, 73 insertions, 60 deletions

diff --git a/execute.c b/execute.c
index 125dc70..4b52fe4 100644
--- a/execute.c
+++ b/execute.c
@@ -562,7 +562,7 @@ static suhosin_internal_function_handler ihandlers[] = {
         S7_IH_ENTRY0i(getrandmax)
         S7_IH_ENTRY0("mt_getrandmax", getrandmax)
         
-        // { "function_exists", ih_function_exists, NULL, NULL, NULL },
+        S7_IH_ENTRY0i(function_exists)
         
         /* Mysqli */
         // { "mysqli::mysqli", ih_fixusername, (void *)2, NULL, NULL },
diff --git a/execute.h b/execute.h
index 4e237b6..9832d41 100644
--- a/execute.h
+++ b/execute.h
@@ -21,6 +21,7 @@ typedef struct _suhosin_internal_function_handler {
 // execute_ih.c
 S7_IH_FUNCTION(preg_replace);
 S7_IH_FUNCTION(symlink);
+S7_IH_FUNCTION(function_exists);
 
 // execute_rnd.c
 S7_IH_FUNCTION(srand);
diff --git a/execute_ih.c b/execute_ih.c
index a59e6c5..ff35a34 100644
--- a/execute_ih.c
+++ b/execute_ih.c
@@ -8,7 +8,6 @@ S7_IH_FUNCTION(preg_replace)
 {
         zval *regex, *replace, *subject, *zcount = NULL;
         zend_long limit = -1;
-        // int replace_count;
 
 #ifndef FAST_ZPP
         /* Get function parameters and do error-checking. */
@@ -69,18 +68,86 @@ S7_IH_FUNCTION(preg_replace)
 S7_IH_FUNCTION(symlink)
 {
         if (SUHOSIN7_G(executor_allow_symlink)) {
-                return (0);
+                return SUCCESS;
         }
         
         if (PG(open_basedir) && PG(open_basedir)[0]) {
                 suhosin_log(S_EXECUTOR, "symlink called during open_basedir");
                 if (!SUHOSIN7_G(simulation)) {
                         RETVAL_FALSE;
-                        return (1);
+                        return FAILURE;
                 }
         }
         
-        return (0);
+        return SUCCESS;
+}
+
+S7_IH_FUNCTION(function_exists)
+{
+        zend_string *name;
+        zend_string *lcname;
+        
+#ifndef FAST_ZPP
+        if (zend_parse_parameters(ZEND_NUM_ARGS(), "S", &name) == FAILURE) {
+                return FAILURE;
+        }
+#else
+        ZEND_PARSE_PARAMETERS_START(1, 1)
+                Z_PARAM_STR(name)
+        ZEND_PARSE_PARAMETERS_END_EX(return FAILURE);
+#endif
+
+        if (ZSTR_VAL(name)[0] == '\\') {
+                /* Ignore leading "\" */
+                lcname = zend_string_alloc(ZSTR_LEN(name) - 1, 0);
+                zend_str_tolower_copy(ZSTR_VAL(lcname), ZSTR_VAL(name) + 1, ZSTR_LEN(name) - 1);
+        } else {
+                lcname = zend_string_tolower(name);
+        }
+
+        zend_function *func = zend_hash_find_ptr(EG(function_table), lcname);
+
+        /*
+         * A bit of a hack, but not a bad one: we see if the handler of the function
+         * is actually one that displays "function is disabled" message.
+         */
+        zend_bool retval = (func && (func->type != ZEND_INTERNAL_FUNCTION ||
+                func->internal_function.handler != zif_display_disabled_function));
+        if (retval == 0) {
+                goto function_exists_return;
+        }
+
+        /* Now check if function is forbidden by Suhosin */
+        if (SUHOSIN7_G(in_code_type) == SUHOSIN_EVAL) {
+                if (SUHOSIN7_G(eval_whitelist) != NULL) {
+                        if (!zend_hash_exists(SUHOSIN7_G(eval_whitelist), lcname)) {
+                            retval = 0;
+                                goto function_exists_return;
+                        }
+                } else if (SUHOSIN7_G(eval_blacklist) != NULL) {
+                        if (zend_hash_exists(SUHOSIN7_G(eval_blacklist), lcname)) {
+                            retval = 0;
+                                goto function_exists_return;
+                        }
+                }
+        }
+        
+        if (SUHOSIN7_G(func_whitelist) != NULL) {
+                if (!zend_hash_exists(SUHOSIN7_G(func_whitelist), lcname)) {
+                    retval = 0;
+                        goto function_exists_return;
+                }
+        } else if (SUHOSIN7_G(func_blacklist) != NULL) {
+                if (zend_hash_exists(SUHOSIN7_G(func_blacklist), lcname)) {
+                    retval = 0;
+                        goto function_exists_return;
+                }
+        }
+
+function_exists_return:
+        zend_string_release(lcname);
+        RETVAL_BOOL(retval);
+        return FAILURE;
 }
 
 // int ih_mail(IH_HANDLER_PARAMS)
@@ -438,58 +505,3 @@ S7_IH_FUNCTION(symlink)
 // }
 // 
 // 
-// static int ih_function_exists(IH_HANDLER_PARAMS)
-// {
-//      zval **function_name;
-//      zend_function *func;
-//      char *lcname;
-//      zend_bool retval;
-//      int func_name_len;
-//      
-//      if (ZEND_NUM_ARGS()!=1 || zend_get_parameters_ex(1, &function_name)==FAILURE) {
-//              ZEND_WRONG_PARAM_COUNT_WITH_RETVAL(1);
-//      }
-//      convert_to_string_ex(function_name);
-//      func_name_len = Z_STRLEN_PP(function_name);
-//      lcname = estrndup(Z_STRVAL_PP(function_name), func_name_len);   
-//      zend_str_tolower(lcname, func_name_len);
-// 
-//      retval = (zend_hash_find(EG(function_table), lcname, func_name_len+1, (void **)&func) == SUCCESS);
-//      
-//      /*
-//       * A bit of a hack, but not a bad one: we see if the handler of the function
-//       * is actually one that displays "function is disabled" message.
-//       */
-//      if (retval && func->type == ZEND_INTERNAL_FUNCTION &&
-//              func->internal_function.handler == zif_display_disabled_function) {
-//              retval = 0;
-//      }
-// 
-//      /* Now check if function is forbidden by Suhosin */
-//      if (SUHOSIN7_G(in_code_type) == SUHOSIN_EVAL) {
-//              if (SUHOSIN7_G(eval_whitelist) != NULL) {
-//                      if (!zend_hash_exists(SUHOSIN7_G(eval_whitelist), lcname, func_name_len+1)) {
-//                          retval = 0;
-//                      }
-//              } else if (SUHOSIN7_G(eval_blacklist) != NULL) {
-//                      if (zend_hash_exists(SUHOSIN7_G(eval_blacklist), lcname, func_name_len+1)) {
-//                          retval = 0;
-//                      }
-//              }
-//      }
-//      
-//      if (SUHOSIN7_G(func_whitelist) != NULL) {
-//              if (!zend_hash_exists(SUHOSIN7_G(func_whitelist), lcname, func_name_len+1)) {
-//                  retval = 0;
-//              }
-//      } else if (SUHOSIN7_G(func_blacklist) != NULL) {
-//              if (zend_hash_exists(SUHOSIN7_G(func_blacklist), lcname, func_name_len+1)) {
-//                  retval = 0;
-//              }
-//      }
-// 
-//      efree(lcname);
-// 
-//      RETVAL_BOOL(retval);
-//      return (1);
-// }