Add func-level OSC-METRICS for GNU fortify-source compiling

README.md

@@ -7,6 +7,7 @@ Table of Contents
 * [Overview](#Overview)
 * [Design Considerations](#Design-Considerations)
 * [Relationship to FORTIFY_SOURCE](#Relationship-to-FORTIFY_SOURCE)
+* [Metric-only Mode for FORTIFY_SOURCE](#Metric-only-Mode-for-FORTIFY_SOURCE)
 * [How to Build OpenOSC Library](#How-to-Build-OpenOSC-Library)
 * [How to Build Packages with OpenOSC Library](#How-to-Build-Packages-with-OpenOSC-Library)
 * [Tested Platforms](#Tested-Platforms)
@@ -177,6 +178,68 @@ Here is a comparison summary table:
 | Logging           | No syslog      | Syslog/Configurable |
 | Cover new routine | Not easy       | Easy                |
 
+Metric-only Mode for FORTIFY_SOURCE
+------------------------------
+The OpenOSC OSC-METRICS feature has been enhanced to work with FORTIFY_SOURCE
+feature enabled.
+
+It is enabled by adding `-DOPENOSC_METRIC_ONLY_MODE` option to CFLAGS.
+
+    CFLAGS += "-include openosc.h -DOPENOSC_METRIC_ONLY_MODE -D_FORTIFY_SOURCE=2"
+
+This does not turn on OSC-METRICS for objsize/copylen. If you want it, add the
+OPENOSC_METRIC_OBJSIZE_ENABLED flag.
+
+    CFLAGS += "-include openosc.h -DOPENOSC_METRIC_ONLY_MODE -DOPENOSC_METRIC_OBJSIZE_ENABLED -D_FORTIFY_SOURCE=2"
+
+This will generate the same OSC-METRICS watermarks for the compiled binary
+file with the OPENOSC_METRIC_FEATURE_ENABLED flag. And you can use the same
+tools/oscmetrics.py script to decode the OSC-METRICS watermarks.
+
+With this OPENOSC_METRIC_ONLY_MODE flag, the memory/string functions will
+always be mapped to itself, except for the addition of OSC-METRICS. The
+generated assembly/binary code should also be the same as before, except for
+the addition of OSC-METRICS. Of course, out-of-order generation of some assembly
+instructions are expected, and still considered the same code.
+
+The nice thing about this metric-only mode is that you don't need to build the
+libopenosc.so library. You don't need to change your linking LDFLAGS, since you
+don't link with any additional library. The only change required is CFLAGS.
+
+Note this Metric-only mode also works without FORTIFY_SOURCE feature. It will
+map all functions to themselves, except for the addition of OSC-METRICS. There
+is no need to change LDFLAGS and no need to build the libopenosc.so library.
+
+    CFLAGS += "-include openosc.h -DOPENOSC_METRIC_ONLY_MODE -U_FORTIFY_SOURCE"
+
+There are multiple flags to control the set of memory/string functions to
+cover. For example, defining OPENOSC_DISABLE_SOCKET_H_FUNCS will not cover
+all functions declared in the sys/socket.h header file, and defining the
+OPENOSC_DISABLE_STDIO_H_FUNCS flag will not cover all functions in the stdio.h
+header file. Defining OPENOSC_POLL_DISABLE will not cover the poll function.
+
+You can also control the level of OSC-METRICS details. For example, you
+can define OPENOSC_NOMAP_METRIC_ONLY to always map all functions to CASE0,
+i.e., the NOMAP case, instead of more detailed CASE1/CASE2/CASE3/CASE4,
+which correnspond to Safe/Overflow/Runtime-protection/Unknown cases,
+respectively. This can help quickly find the occurrences of all function
+invocations in your code. By default, source buffer overread feature is ON,
+but you can define the OPENOSC_SRC_OVERREAD_DISABLE flag to turn if off.
+
+One disadvantage of this Metric-only mode is: it can suppress some
+compile-time warning messages that are defined by function attributes
+of the OpenOSC covered functions, for example, the warn-unused-result
+or nonnull function attribute.
+
+The clang compiler seems to implement its fortify-source buffer-overflow warning
+messages with function attributes, thus the buffer-overflow warnings messages
+are also suppressed with the Metric-only mode in clang. If clang can also check
+the warning condition in the optimization phase, in addition to the front-end
+(pre-optimization phase), then this issue can be fixed.
+
+The gcc and icc compiler have no such issue, and are able to report compile-time
+buffer-overflow warning messages, with Metric-only mode.
+
 How to Build OpenOSC Library
 ----------------------------
 The build system for the OpenOSC library is the well known GNU build system,
@@ -319,6 +382,11 @@ Known Issues
 However, OPENOSC_METRIC_OBJSIZE_ENABLED impacts the compilation performance
 significantly, especially for Clang.
 
+3. OPENOSC_METRIC_ONLY_MODE suppresses some compile-time warning messages that
+are implemented by function attributes of the covered functions, like
+-Wunused-result. Fortify-source buffer-overflow warnings are suppressed for
+clang, but not for gcc/icc.
+
 References
 ----------
 - [1] OpenOSC: Open Source Object Size Checking Library With Built-in

VERSION

@@ -1 +1 @@
-1.0.4
+1.0.5

configure

@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for openosc 1.0.4.
+# Generated by GNU Autoconf 2.69 for openosc 1.0.5.
 #
 # Report bugs to <yonhan@cisco.com>.
 #
@@ -590,8 +590,8 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='openosc'
 PACKAGE_TARNAME='openosc'
-PACKAGE_VERSION='1.0.4'
-PACKAGE_STRING='openosc 1.0.4'
+PACKAGE_VERSION='1.0.5'
+PACKAGE_STRING='openosc 1.0.5'
 PACKAGE_BUGREPORT='yonhan@cisco.com'
 PACKAGE_URL=''
 
@@ -1329,7 +1329,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures openosc 1.0.4 to adapt to many kinds of systems.
+\`configure' configures openosc 1.0.5 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1399,7 +1399,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of openosc 1.0.4:";;
+     short | recursive ) echo "Configuration of openosc 1.0.5:";;
    esac
   cat <<\_ACEOF
 
@@ -1508,7 +1508,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-openosc configure 1.0.4
+openosc configure 1.0.5
 generated by GNU Autoconf 2.69
 
 Copyright (C) 2012 Free Software Foundation, Inc.
@@ -1998,7 +1998,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by openosc $as_me 1.0.4, which was
+It was created by openosc $as_me 1.0.5, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   $ $0 $@
@@ -2861,7 +2861,7 @@ fi
 
 # Define the identity of the package.
  PACKAGE='openosc'
- VERSION='1.0.4'
+ VERSION='1.0.5'
 
 
 cat >>confdefs.h <<_ACEOF
@@ -16738,7 +16738,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by openosc $as_me 1.0.4, which was
+This file was extended by openosc $as_me 1.0.5, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -16804,7 +16804,7 @@ _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-openosc config.status 1.0.4
+openosc config.status 1.0.5
 configured by $0, generated by GNU Autoconf 2.69,
   with options \\"\$ac_cs_config\\"
 

include/openosc.h

@@ -13,6 +13,19 @@
 
 #include "openosc_header_metric.h"
 
+/* define the object size checking type in builtin function */
+#define OSC_OBJECT_SIZE_CHECK_0 0
+#define OSC_OBJECT_SIZE_CHECK_1 1
+
+#ifndef NULL
+#define NULL ((void *)0)
+#endif
+
+/* Source over-read is enabled by default, but can be disabled */
+#ifndef OPENOSC_SRC_OVERREAD_DISABLE
+#define _OPENOSC_SRC_OVERREAD_ENABLED
+#endif
+
 /*
  * There are two methods to remap a function to openosc_* function:
  *   1. The function redirect via ASM-label mechanism.
@@ -40,10 +53,25 @@
 #define NO_OBJECT_SIZE_CHECKING
 #endif
 
+#ifdef OPENOSC_SKIP_CSTRING_HEADER
+#ifdef __cplusplus
+#if OPENOSC_MAPPING_METHOD == OPENOSC_FUNC_MACRO_REDEFINE_METHOD || defined OPENOSC_METRIC_ONLY_MODE
+/* define the below macro to avoid including <cstring> header, which #undef >10 memcpy/strcpy functions */
+#ifndef _GLIBCXX_CSTRING
+#define _GLIBCXX_CSTRING 2
+#endif
+#endif
+#endif
+#endif
+
+
 #ifdef NO_OBJECT_SIZE_CHECKING
 #pragma message ("OSC-WARN-DISABLED: OpenOSC disabled due to NO_OBJECT_SIZE_CHECKING, contact OpenOSC package owner for guidance")
 #elif defined __ASSEMBLER__
 #pragma message ("OSC-WARN-ASM: OpenOSC disabled due to __ASSEMBLER__, contact OpenOSC package owner for guidance")
+#elif defined OPENOSC_METRIC_ONLY_MODE
+#pragma message ("OSC-WARN-METRICONLY: OpenOSC disabled due to METRIC_ONLY_MODE, contact OpenOSC package owner for guidance")
+#include "openosc_metric_only.h"
 #elif !defined  __OPTIMIZE__
 /* #error "OSC-ERR-NOOPT: OpenOSC disabled due to NO OPTIMIZATION, contact OpenOSC package owner for guidance" */
 #pragma message ("OSC-ERR-NOOPT: OpenOSC disabled due to NO OPTIMIZATION, contact OpenOSC package owner for guidance")
@@ -148,10 +176,6 @@
  **********************************************************************************
  **********************************************************************************/
 
-/* define the object size checking type in builtin function */
-#define OSC_OBJECT_SIZE_CHECK_0 0
-#define OSC_OBJECT_SIZE_CHECK_1 1
-
 #include "openosc_map.h"
 
 #ifdef HAS_SAFEC

include/openosc_extern.h

@@ -20,11 +20,13 @@
 typedef __builtin_va_list va_list;
 #endif
 
+#ifndef OSC_THROW
 #ifdef __cplusplus
 #define OSC_THROW __THROW
 #else
 #define OSC_THROW
 #endif
+#endif
 
 /* libC APIs */
 extern void *memcpy(void *dst, const void *src, size_t len) OSC_THROW;

include/openosc_fortify.h

@@ -207,10 +207,6 @@
 #endif
 
 
-/* Source over-read is enabled by default, but can be disabled */
-#ifndef OPENOSC_SRC_OVERREAD_DISABLE
-#define _OPENOSC_SRC_OVERREAD_ENABLED
-#endif
 /* Errors are reported at compile-time unless you disable it explicitly */
 #ifndef OPENOSC_OVERFLOW_ERROR_OUT_DISABLE
 /* Do we want to error out at compile-time when detecting overflow/overread */

include/openosc_fortify_extern.h

@@ -19,11 +19,13 @@
 typedef __builtin_va_list va_list;
 #endif
 
+#ifndef OSC_THROW
 #ifdef __cplusplus
 #define OSC_THROW __THROW
 #else
 #define OSC_THROW
 #endif
+#endif
 
 
 /* The below data type forward declarations are required */

include/openosc_fortify_redefine_map.h

@@ -1099,6 +1099,8 @@ openosc_gethostname (char *name, size_t len)
 #define gethostname(name, len)		openosc_gethostname(name, len)
 
 
+#ifndef OPENOSC_GETS_DISABLE
+
 #ifndef __cplusplus
 /* Mapping for gets */
 
@@ -1123,6 +1125,8 @@ openosc_gets (char *s)
 #define gets(s)		openosc_gets(s)
 #endif /* __cplusplus */
 
+#endif /* OPENOSC_GETS_DISABLE */
+
 
 /* Mapping for getwd */
 

include/openosc_fortify_redefine_nomap.h

@@ -306,6 +306,8 @@ openosc_gethostname (char *name, size_t len)
 #define gethostname(name, len)		openosc_gethostname(name, len)
 
 
+#ifndef OPENOSC_GETS_DISABLE
+
 /* Mapping for gets */
 
 static inline __attribute__ ((always_inline))
@@ -318,6 +320,8 @@ openosc_gets (char *s)
 #undef gets
 #define gets(s)		openosc_gets(s)
 
+#endif /* OPENOSC_GETS_DISABLE */
+
 
 /* Mapping for getwd */
 

include/openosc_fortify_redirect_map.h

@@ -706,6 +706,8 @@ __clang_warn_or_error_if(__size_too_small (__bos1, name, len), __dst_overflow_ms
 }
 
 
+#ifndef OPENOSC_GETS_DISABLE
+
 /* Mapping for gets */
 
 extern char *
@@ -727,6 +729,8 @@ gets (char * __pass_objsize1 s)
 #endif
 }
 
+#endif /* OPENOSC_GETS_DISABLE */
+
 
 /* Mapping for getwd */
 

include/openosc_fortify_redirect_nomap.h

@@ -276,6 +276,8 @@ __NTH (gethostname(char *name, size_t len))
 }
 
 
+#ifndef OPENOSC_GETS_DISABLE
+
 /* Mapping for gets */
 
 extern char * __REDIRECT (__openosc_gets_alias,
@@ -287,6 +289,8 @@ gets(char *s)
     return (GETS_NOMAP_CASE __openosc_gets_alias(s));
 }
 
+#endif /* OPENOSC_GETS_DISABLE */
+
 
 /* Mapping for getwd */
 

include/openosc_map_metric.h

@@ -10,18 +10,6 @@
 #ifndef __OPENOSC_MAP_METRIC_H__
 #define __OPENOSC_MAP_METRIC_H__
 
-#ifdef OPENOSC_HEADER_METRIC_FEATURE_ENABLED
-
-/* always insert a magic word if osc_map.h is included */
-#if defined __BIG_ENDIAN__ || defined __BIG_ENDIAN || (defined __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
-#define MAGIC_OSC_MAP_H_INCLUDED 0x80818d8f80818d8e
-#else
-#define MAGIC_OSC_MAP_H_INCLUDED 0x8e8d81808f8d8180
-#endif
-long long int __attribute__((weak)) rtd_osc_map_h_included_int = MAGIC_OSC_MAP_H_INCLUDED;
-
-#endif /* OPENOSC_HEADER_METRIC_FEATURE_ENABLED */
-
 #ifdef OPENOSC_METRIC_FEATURE_ENABLED
 
 #include "openosc_metric_objsize.h"