Merge branch 'nse-lua53'

Lua 5.3 adds several awesome features of particular interest to nmap including
bitwise operators and integers, a utf8 library, and standard binary pack/unpack
functions.

In addition to adding Lua 5.3, this branch changes:

o Complete removal of the NSE bit library (in C), It has been replaced with
  a new Lua library wrapping Lua 5.3's bit-wise operators.

o Complete removal of the NSE bin library (in C). It has been replaced with a
  new Lua library wrapping Lua 5.3's string.pack|unpack functions.

o The bin.pack "B" format specifier (which has never worked correctly) is
  unimplemented.  All scripts/libraries which use it have been updated. Most
  usage of this option was to allow string based bit-wise operations which are no
  longer necessary now that Lua 5.3 provides integers and bit-wise operators.

o The base32/base64 libraries have been reimplemented using Lua 5.3's new
  bitwise operators. (This library was the main user of the bin.pack "B" format
  specifier.)

o A new "bits" library has been added for common bit hacks. Currently only has
  a reverse function.

Thanks to David Fifield, Daniel Miller, Jacek Wielemborek, and  Paulino
Calderon for testing this branch.

liblua/loslib.c

@@ -1,9 +1,14 @@
 /*
-** $Id: loslib.c,v 1.40.1.1 2013/04/12 18:48:47 roberto Exp $
+** $Id: loslib.c,v 1.64 2016/04/18 13:06:55 roberto Exp $
 ** Standard Operating System library
 ** See Copyright Notice in lua.h
 */
 
+#define loslib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
 
 #include <errno.h>
 #include <locale.h>
@@ -11,9 +16,6 @@
 #include <string.h>
 #include <time.h>
 
-#define loslib_c
-#define LUA_LIB
-
 #include "lua.h"
 
 #include "lauxlib.h"
@@ -21,60 +23,119 @@
 
 
 /*
-** list of valid conversion specifiers for the 'strftime' function
+** {==================================================================
+** List of valid conversion specifiers for the 'strftime' function;
+** options are grouped by length; group of length 2 start with '||'.
+** ===================================================================
 */
-#if !defined(LUA_STRFTIMEOPTIONS)
-
-#if !defined(LUA_USE_POSIX)
-#define LUA_STRFTIMEOPTIONS	{ "aAbBcdHIjmMpSUwWxXyYz%", "" }
-#else
-#define LUA_STRFTIMEOPTIONS \
-	{ "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%", "" \
-	  "", "E", "cCxXyY",  \
-	  "O", "deHImMSuUVwWy" }
-#endif
+#if !defined(LUA_STRFTIMEOPTIONS)	/* { */
 
+/* options for ANSI C 89 */
+#define L_STRFTIMEC89		"aAbBcdHIjmMpSUwWxXyYZ%"
+
+/* options for ISO C 99 and POSIX */
+#define L_STRFTIMEC99 "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
+	"||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"
+
+/* options for Windows */
+#define L_STRFTIMEWIN "aAbBcdHIjmMpSUwWxXyYzZ%" \
+	"||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"
+
+#if defined(LUA_USE_WINDOWS)
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEWIN
+#elif defined(LUA_USE_C89)
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC89
+#else  /* C99 specification */
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC99
 #endif
 
+#endif					/* } */
+/* }================================================================== */
 
 
 /*
-** By default, Lua uses tmpnam except when POSIX is available, where it
-** uses mkstemp.
+** {==================================================================
+** Configuration for time-related stuff
+** ===================================================================
 */
-#if defined(LUA_USE_MKSTEMP)
-#include <unistd.h>
-#define LUA_TMPNAMBUFSIZE	32
-#define lua_tmpnam(b,e) { \
-        strcpy(b, "/tmp/lua_XXXXXX"); \
-        e = mkstemp(b); \
-        if (e != -1) close(e); \
-        e = (e == -1); }
 
-#elif !defined(lua_tmpnam)
+#if !defined(l_time_t)		/* { */
+/*
+** type to represent time_t in Lua
+*/
+#define l_timet			lua_Integer
+#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
 
-#define LUA_TMPNAMBUFSIZE	L_tmpnam
-#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
+static time_t l_checktime (lua_State *L, int arg) {
+  lua_Integer t = luaL_checkinteger(L, arg);
+  luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
+  return (time_t)t;
+}
 
-#endif
+#endif				/* } */
 
 
+#if !defined(l_gmtime)		/* { */
 /*
 ** By default, Lua uses gmtime/localtime, except when POSIX is available,
 ** where it uses gmtime_r/localtime_r
 */
-#if defined(LUA_USE_GMTIME_R)
+
+#if defined(LUA_USE_POSIX)	/* { */
 
 #define l_gmtime(t,r)		gmtime_r(t,r)
 #define l_localtime(t,r)	localtime_r(t,r)
 
-#elif !defined(l_gmtime)
+#else				/* }{ */
 
-#define l_gmtime(t,r)		((void)r, gmtime(t))
-#define l_localtime(t,r)  	((void)r, localtime(t))
+/* ISO C definitions */
+#define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
+#define l_localtime(t,r)  	((void)(r)->tm_sec, localtime(t))
 
+#endif				/* } */
+
+#endif				/* } */
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Configuration for 'tmpnam':
+** By default, Lua uses tmpnam except when POSIX is available, where
+** it uses mkstemp.
+** ===================================================================
+*/
+#if !defined(lua_tmpnam)	/* { */
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#include <unistd.h>
+
+#define LUA_TMPNAMBUFSIZE	32
+
+#if !defined(LUA_TMPNAMTEMPLATE)
+#define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
 #endif
 
+#define lua_tmpnam(b,e) { \
+        strcpy(b, LUA_TMPNAMTEMPLATE); \
+        e = mkstemp(b); \
+        if (e != -1) close(e); \
+        e = (e == -1); }
+
+#else				/* }{ */
+
+/* ISO C definitions */
+#define LUA_TMPNAMBUFSIZE	L_tmpnam
+#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
+
+#endif				/* } */
+
+#endif				/* } */
+/* }================================================================== */
+
+
 
 
 static int os_execute (lua_State *L) {
@@ -145,45 +206,67 @@ static void setboolfield (lua_State *L, const char *key, int value) {
   lua_setfield(L, -2, key);
 }
 
+
+/*
+** Set all fields from structure 'tm' in the table on top of the stack
+*/
+static void setallfields (lua_State *L, struct tm *stm) {
+  setfield(L, "sec", stm->tm_sec);
+  setfield(L, "min", stm->tm_min);
+  setfield(L, "hour", stm->tm_hour);
+  setfield(L, "day", stm->tm_mday);
+  setfield(L, "month", stm->tm_mon + 1);
+  setfield(L, "year", stm->tm_year + 1900);
+  setfield(L, "wday", stm->tm_wday + 1);
+  setfield(L, "yday", stm->tm_yday + 1);
+  setboolfield(L, "isdst", stm->tm_isdst);
+}
+
+
 static int getboolfield (lua_State *L, const char *key) {
   int res;
-  lua_getfield(L, -1, key);
-  res = lua_isnil(L, -1) ? -1 : lua_toboolean(L, -1);
+  res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
   lua_pop(L, 1);
   return res;
 }
 
 
-static int getfield (lua_State *L, const char *key, int d) {
-  int res, isnum;
-  lua_getfield(L, -1, key);
-  res = (int)lua_tointegerx(L, -1, &isnum);
-  if (!isnum) {
-    if (d < 0)
-      return luaL_error(L, "field " LUA_QS " missing in date table", key);
+/* maximum value for date fields (to avoid arithmetic overflows with 'int') */
+#if !defined(L_MAXDATEFIELD)
+#define L_MAXDATEFIELD	(INT_MAX / 2)
+#endif
+
+static int getfield (lua_State *L, const char *key, int d, int delta) {
+  int isnum;
+  int t = lua_getfield(L, -1, key);  /* get field and its type */
+  lua_Integer res = lua_tointegerx(L, -1, &isnum);
+  if (!isnum) {  /* field is not an integer? */
+    if (t != LUA_TNIL)  /* some other value? */
+      return luaL_error(L, "field '%s' is not an integer", key);
+    else if (d < 0)  /* absent field; no default? */
+      return luaL_error(L, "field '%s' missing in date table", key);
     res = d;
   }
+  else {
+    if (!(-L_MAXDATEFIELD <= res && res <= L_MAXDATEFIELD))
+      return luaL_error(L, "field '%s' is out-of-bound", key);
+    res -= delta;
+  }
   lua_pop(L, 1);
-  return res;
+  return (int)res;
 }
 
 
 static const char *checkoption (lua_State *L, const char *conv, char *buff) {
-  static const char *const options[] = LUA_STRFTIMEOPTIONS;
-  unsigned int i;
-  for (i = 0; i < sizeof(options)/sizeof(options[0]); i += 2) {
-    if (*conv != '\0' && strchr(options[i], *conv) != NULL) {
-      buff[1] = *conv;
-      if (*options[i + 1] == '\0') {  /* one-char conversion specifier? */
-        buff[2] = '\0';  /* end buffer */
-        return conv + 1;
-      }
-      else if (*(conv + 1) != '\0' &&
-               strchr(options[i + 1], *(conv + 1)) != NULL) {
-        buff[2] = *(conv + 1);  /* valid two-char conversion specifier */
-        buff[3] = '\0';  /* end buffer */
-        return conv + 2;
-      }
+  const char *option;
+  int oplen = 1;
+  for (option = LUA_STRFTIMEOPTIONS; *option != '\0'; option += oplen) {
+    if (*option == '|')  /* next block? */
+      oplen++;  /* next length */
+    else if (memcmp(conv, option, oplen) == 0) {  /* match? */
+      memcpy(buff, conv, oplen);  /* copy valid option to buffer */
+      buff[oplen] = '\0';
+      return conv + oplen;  /* return next item */
     }
   }
   luaL_argerror(L, 1,
@@ -192,44 +275,40 @@ static const char *checkoption (lua_State *L, const char *conv, char *buff) {
 }
 
 
+/* maximum size for an individual 'strftime' item */
+#define SIZETIMEFMT	250
+
+
 static int os_date (lua_State *L) {
   const char *s = luaL_optstring(L, 1, "%c");
-  time_t t = luaL_opt(L, (time_t)luaL_checknumber, 2, time(NULL));
+  time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
   struct tm tmr, *stm;
   if (*s == '!') {  /* UTC? */
     stm = l_gmtime(&t, &tmr);
-    s++;  /* skip `!' */
+    s++;  /* skip '!' */
   }
   else
     stm = l_localtime(&t, &tmr);
   if (stm == NULL)  /* invalid date? */
-    lua_pushnil(L);
-  else if (strcmp(s, "*t") == 0) {
+    luaL_error(L, "time result cannot be represented in this installation");
+  if (strcmp(s, "*t") == 0) {
     lua_createtable(L, 0, 9);  /* 9 = number of fields */
-    setfield(L, "sec", stm->tm_sec);
-    setfield(L, "min", stm->tm_min);
-    setfield(L, "hour", stm->tm_hour);
-    setfield(L, "day", stm->tm_mday);
-    setfield(L, "month", stm->tm_mon+1);
-    setfield(L, "year", stm->tm_year+1900);
-    setfield(L, "wday", stm->tm_wday+1);
-    setfield(L, "yday", stm->tm_yday+1);
-    setboolfield(L, "isdst", stm->tm_isdst);
+    setallfields(L, stm);
   }
   else {
-    char cc[4];
+    char cc[4];  /* buffer for individual conversion specifiers */
     luaL_Buffer b;
     cc[0] = '%';
     luaL_buffinit(L, &b);
     while (*s) {
-      if (*s != '%')  /* no conversion specifier? */
+      if (*s != '%')  /* not a conversion specifier? */
         luaL_addchar(&b, *s++);
       else {
         size_t reslen;
-        char buff[200];  /* should be big enough for any conversion result */
-        s = checkoption(L, s + 1, cc);
-        reslen = strftime(buff, sizeof(buff), cc, stm);
-        luaL_addlstring(&b, buff, reslen);
+        char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
+        s = checkoption(L, s + 1, cc + 1);  /* copy specifier to 'cc' */
+        reslen = strftime(buff, SIZETIMEFMT, cc, stm);
+        luaL_addsize(&b, reslen);
       }
     }
     luaL_pushresult(&b);
@@ -246,26 +325,27 @@ static int os_time (lua_State *L) {
     struct tm ts;
     luaL_checktype(L, 1, LUA_TTABLE);
     lua_settop(L, 1);  /* make sure table is at the top */
-    ts.tm_sec = getfield(L, "sec", 0);
-    ts.tm_min = getfield(L, "min", 0);
-    ts.tm_hour = getfield(L, "hour", 12);
-    ts.tm_mday = getfield(L, "day", -1);
-    ts.tm_mon = getfield(L, "month", -1) - 1;
-    ts.tm_year = getfield(L, "year", -1) - 1900;
+    ts.tm_sec = getfield(L, "sec", 0, 0);
+    ts.tm_min = getfield(L, "min", 0, 0);
+    ts.tm_hour = getfield(L, "hour", 12, 0);
+    ts.tm_mday = getfield(L, "day", -1, 0);
+    ts.tm_mon = getfield(L, "month", -1, 1);
+    ts.tm_year = getfield(L, "year", -1, 1900);
     ts.tm_isdst = getboolfield(L, "isdst");
     t = mktime(&ts);
+    setallfields(L, &ts);  /* update fields with normalized values */
   }
-  if (t == (time_t)(-1))
-    lua_pushnil(L);
-  else
-    lua_pushnumber(L, (lua_Number)t);
+  if (t != (time_t)(l_timet)t || t == (time_t)(-1))
+    luaL_error(L, "time result cannot be represented in this installation");
+  l_pushtime(L, t);
   return 1;
 }
 
 
 static int os_difftime (lua_State *L) {
-  lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),
-                             (time_t)(luaL_optnumber(L, 2, 0))));
+  time_t t1 = l_checktime(L, 1);
+  time_t t2 = l_checktime(L, 2);
+  lua_pushnumber(L, (lua_Number)difftime(t1, t2));
   return 1;
 }
 
@@ -289,7 +369,7 @@ static int os_exit (lua_State *L) {
   if (lua_isboolean(L, 1))
     status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
   else
-    status = luaL_optint(L, 1, EXIT_SUCCESS);
+    status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
   if (lua_toboolean(L, 2))
     lua_close(L);
   if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */