diff options
-rw-r--r-- | newlib/libc/include/string.h | 1 | ||||
-rw-r--r-- | newlib/libc/string/Makefile.am | 1 | ||||
-rw-r--r-- | newlib/libc/string/Makefile.in | 44 | ||||
-rw-r--r-- | newlib/libc/string/timingsafe_memcmp.c | 46 |
4 files changed, 74 insertions, 18 deletions
diff --git a/newlib/libc/include/string.h b/newlib/libc/include/string.h index 2bda8f952..68ee41285 100644 --- a/newlib/libc/include/string.h +++ b/newlib/libc/include/string.h @@ -54,6 +54,7 @@ void _EXFUN(bzero,(void *, size_t)); #if __BSD_VISIBLE void _EXFUN(explicit_bzero,(void *, size_t)); int _EXFUN(timingsafe_bcmp,(const void *, const void *, size_t)); +int _EXFUN(timingsafe_memcmp,(const void *, const void *, size_t)); #endif #if __MISC_VISIBLE || __POSIX_VISIBLE >= 200809 int _EXFUN(ffs,(int)); diff --git a/newlib/libc/string/Makefile.am b/newlib/libc/string/Makefile.am index c227bbda9..1c047f532 100644 --- a/newlib/libc/string/Makefile.am +++ b/newlib/libc/string/Makefile.am @@ -47,6 +47,7 @@ GENERAL_SOURCES = \ strstr.c \ swab.c \ timingsafe_bcmp.c \ + timingsafe_memcmp.c \ u_strerr.c \ wcscat.c \ wcschr.c \ diff --git a/newlib/libc/string/Makefile.in b/newlib/libc/string/Makefile.in index 1db7f0e62..4d42c9099 100644 --- a/newlib/libc/string/Makefile.in +++ b/newlib/libc/string/Makefile.in @@ -93,20 +93,21 @@ am__objects_1 = lib_a-bcopy.$(OBJEXT) lib_a-bzero.$(OBJEXT) \ lib_a-strtok_r.$(OBJEXT) lib_a-strupr.$(OBJEXT) \ lib_a-strxfrm.$(OBJEXT) lib_a-strstr.$(OBJEXT) \ lib_a-swab.$(OBJEXT) lib_a-timingsafe_bcmp.$(OBJEXT) \ - lib_a-u_strerr.$(OBJEXT) lib_a-wcscat.$(OBJEXT) \ - lib_a-wcschr.$(OBJEXT) lib_a-wcscmp.$(OBJEXT) \ - lib_a-wcscoll.$(OBJEXT) lib_a-wcscpy.$(OBJEXT) \ - lib_a-wcscspn.$(OBJEXT) lib_a-wcslcat.$(OBJEXT) \ - lib_a-wcslcpy.$(OBJEXT) lib_a-wcslen.$(OBJEXT) \ - lib_a-wcsncat.$(OBJEXT) lib_a-wcsncmp.$(OBJEXT) \ - lib_a-wcsncpy.$(OBJEXT) lib_a-wcsnlen.$(OBJEXT) \ - lib_a-wcspbrk.$(OBJEXT) lib_a-wcsrchr.$(OBJEXT) \ - lib_a-wcsspn.$(OBJEXT) lib_a-wcsstr.$(OBJEXT) \ - lib_a-wcstok.$(OBJEXT) lib_a-wcswidth.$(OBJEXT) \ - lib_a-wcsxfrm.$(OBJEXT) lib_a-wcwidth.$(OBJEXT) \ - lib_a-wmemchr.$(OBJEXT) lib_a-wmemcmp.$(OBJEXT) \ - lib_a-wmemcpy.$(OBJEXT) lib_a-wmemmove.$(OBJEXT) \ - lib_a-wmemset.$(OBJEXT) lib_a-xpg_strerror_r.$(OBJEXT) + lib_a-timingsafe_memcmp.$(OBJEXT) lib_a-u_strerr.$(OBJEXT) \ + lib_a-wcscat.$(OBJEXT) lib_a-wcschr.$(OBJEXT) \ + lib_a-wcscmp.$(OBJEXT) lib_a-wcscoll.$(OBJEXT) \ + lib_a-wcscpy.$(OBJEXT) lib_a-wcscspn.$(OBJEXT) \ + lib_a-wcslcat.$(OBJEXT) lib_a-wcslcpy.$(OBJEXT) \ + lib_a-wcslen.$(OBJEXT) lib_a-wcsncat.$(OBJEXT) \ + lib_a-wcsncmp.$(OBJEXT) lib_a-wcsncpy.$(OBJEXT) \ + lib_a-wcsnlen.$(OBJEXT) lib_a-wcspbrk.$(OBJEXT) \ + lib_a-wcsrchr.$(OBJEXT) lib_a-wcsspn.$(OBJEXT) \ + lib_a-wcsstr.$(OBJEXT) lib_a-wcstok.$(OBJEXT) \ + lib_a-wcswidth.$(OBJEXT) lib_a-wcsxfrm.$(OBJEXT) \ + lib_a-wcwidth.$(OBJEXT) lib_a-wmemchr.$(OBJEXT) \ + lib_a-wmemcmp.$(OBJEXT) lib_a-wmemcpy.$(OBJEXT) \ + lib_a-wmemmove.$(OBJEXT) lib_a-wmemset.$(OBJEXT) \ + lib_a-xpg_strerror_r.$(OBJEXT) @ELIX_LEVEL_1_FALSE@am__objects_2 = lib_a-bcmp.$(OBJEXT) \ @ELIX_LEVEL_1_FALSE@ lib_a-memccpy.$(OBJEXT) \ @ELIX_LEVEL_1_FALSE@ lib_a-mempcpy.$(OBJEXT) \ @@ -138,10 +139,10 @@ am__objects_4 = bcopy.lo bzero.lo explicit_bzero.lo index.lo memchr.lo \ strncasecmp.lo strncat.lo strncmp.lo strncpy.lo strnlen.lo \ strpbrk.lo strrchr.lo strsep.lo strsignal.lo strspn.lo \ strtok.lo strtok_r.lo strupr.lo strxfrm.lo strstr.lo swab.lo \ - timingsafe_bcmp.lo u_strerr.lo wcscat.lo wcschr.lo wcscmp.lo \ - wcscoll.lo wcscpy.lo wcscspn.lo wcslcat.lo wcslcpy.lo \ - wcslen.lo wcsncat.lo wcsncmp.lo wcsncpy.lo wcsnlen.lo \ - wcspbrk.lo wcsrchr.lo wcsspn.lo wcsstr.lo wcstok.lo \ + timingsafe_bcmp.lo timingsafe_memcmp.lo u_strerr.lo wcscat.lo \ + wcschr.lo wcscmp.lo wcscoll.lo wcscpy.lo wcscspn.lo wcslcat.lo \ + wcslcpy.lo wcslen.lo wcsncat.lo wcsncmp.lo wcsncpy.lo \ + wcsnlen.lo wcspbrk.lo wcsrchr.lo wcsspn.lo wcsstr.lo wcstok.lo \ wcswidth.lo wcsxfrm.lo wcwidth.lo wmemchr.lo wmemcmp.lo \ wmemcpy.lo wmemmove.lo wmemset.lo xpg_strerror_r.lo @ELIX_LEVEL_1_FALSE@am__objects_5 = bcmp.lo memccpy.lo mempcpy.lo \ @@ -371,6 +372,7 @@ GENERAL_SOURCES = \ strstr.c \ swab.c \ timingsafe_bcmp.c \ + timingsafe_memcmp.c \ u_strerr.c \ wcscat.c \ wcschr.c \ @@ -781,6 +783,12 @@ lib_a-timingsafe_bcmp.o: timingsafe_bcmp.c lib_a-timingsafe_bcmp.obj: timingsafe_bcmp.c $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-timingsafe_bcmp.obj `if test -f 'timingsafe_bcmp.c'; then $(CYGPATH_W) 'timingsafe_bcmp.c'; else $(CYGPATH_W) '$(srcdir)/timingsafe_bcmp.c'; fi` +lib_a-timingsafe_memcmp.o: timingsafe_memcmp.c + $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-timingsafe_memcmp.o `test -f 'timingsafe_memcmp.c' || echo '$(srcdir)/'`timingsafe_memcmp.c + +lib_a-timingsafe_memcmp.obj: timingsafe_memcmp.c + $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-timingsafe_memcmp.obj `if test -f 'timingsafe_memcmp.c'; then $(CYGPATH_W) 'timingsafe_memcmp.c'; else $(CYGPATH_W) '$(srcdir)/timingsafe_memcmp.c'; fi` + lib_a-u_strerr.o: u_strerr.c $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-u_strerr.o `test -f 'u_strerr.c' || echo '$(srcdir)/'`u_strerr.c diff --git a/newlib/libc/string/timingsafe_memcmp.c b/newlib/libc/string/timingsafe_memcmp.c new file mode 100644 index 000000000..04e2ac5e2 --- /dev/null +++ b/newlib/libc/string/timingsafe_memcmp.c @@ -0,0 +1,46 @@ +/* $OpenBSD: timingsafe_memcmp.c,v 1.1 2014/06/13 02:12:17 matthew Exp $ */ +/* + * Copyright (c) 2014 Google Inc. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <limits.h> +#include <string.h> + +int +timingsafe_memcmp(const void *b1, const void *b2, size_t len) +{ + const unsigned char *p1 = b1, *p2 = b2; + size_t i; + int res = 0, done = 0; + + for (i = 0; i < len; i++) { + /* lt is -1 if p1[i] < p2[i]; else 0. */ + int lt = (p1[i] - p2[i]) >> CHAR_BIT; + + /* gt is -1 if p1[i] > p2[i]; else 0. */ + int gt = (p2[i] - p1[i]) >> CHAR_BIT; + + /* cmp is 1 if p1[i] > p2[i]; -1 if p1[i] < p2[i]; else 0. */ + int cmp = lt - gt; + + /* set res = cmp if !done. */ + res |= cmp & ~done; + + /* set done if p1[i] != p2[i]. */ + done |= lt | gt; + } + + return (res); +} |