Skip to content

Commit

Permalink
Fix false positives of IS_*() macros for 8-bit ASCII characters
Browse files Browse the repository at this point in the history 
Fixes openssl#5778, openssl#5840

The various IS_*() macros did not work correctly for 8-bit ASCII
characters with the high bit set, because the CVT(a) preprocessor
macro and'ed the given ASCII value with 0x7F, effectively folding
the high value range 128-255 over the low value range 0-127.
As a consequence, some of the IS_*() erroneously returned TRUE.

This commit fixes the issue by adding range checks instead of
cutting off high order bits using a mask. In order avoid multiple
evaluation of macro arguments, most of the implementation was moved
from macros into a static function is_keytype().

Thanks to Румен Петров for reporting and analyzing the UTF-8 parsing
issue openssl#5840.
  • Loading branch information
@mspncp
mspncp committed Apr 7, 2018
1 parent 69b1500 commit 2994483
Show file tree
Hide file tree
Showing 3 changed files with 45 additions and 34 deletions.
25 changes: 25 additions & 0 deletions crypto/conf/conf_def.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -33,6 +33,7 @@
*/
#define MAX_CONF_VALUE_LENGTH 65536

static int is_keytype(const CONF *conf, char c, unsigned short type);
static char *eat_ws(CONF *conf, char *p);
static void trim_ws(CONF *conf, char *start);
static char *eat_alpha_numeric(CONF *conf, char *p);
Expand Down Expand Up @@ -732,6 +733,30 @@ static BIO *get_next_file(const char *path, OPENSSL_DIR_CTX **dirctx)
}
#endif

static int is_keytype(const CONF *conf, char c, unsigned short type)
{
const unsigned short * keytypes = (const unsigned short *) conf->meth_data;
unsigned char key = (unsigned char)c;

#ifdef CHARSET_EBCDIC
# if CHAR_BIT > 8
if (key > 255) {
/* key is out of range for os_toascii table */
return 0;
}
# endif
/* convert key from ebcdic to ascii */
key = os_toascii[key];
#endif

if (key > 127) {
/* key is not a seven bit ascii character */
return 0;
}

return (keytypes[key] & type) ? 1 : 0;
}

static char *eat_ws(CONF *conf, char *p)
{
while (IS_WS(conf, *p) && (!IS_EOF(conf, *p)))
Expand Down
27 changes: 10 additions & 17 deletions crypto/conf/conf_def.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,24 +25,17 @@
#define CONF_ALNUM (CONF_ALPHA|CONF_NUMBER|CONF_UNDER)
#define CONF_ALNUM_PUNCT (CONF_ALPHA|CONF_NUMBER|CONF_UNDER|CONF_PUNCT)

#define KEYTYPES(c) ((const unsigned short *)((c)->meth_data))

#ifndef CHARSET_EBCDIC
# define CVT(a) ((a) & 0x7F)
#else
# define CVT(a) os_toascci[(a) & 0x7F]
#endif

#define IS_COMMENT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_COMMENT)
#define IS_FCOMMENT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_FCOMMENT)
#define IS_EOF(c,a) (KEYTYPES(c)[CVT(a)] & CONF_EOF)
#define IS_ESC(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ESC)
#define IS_NUMBER(c,a) (KEYTYPES(c)[CVT(a)] & CONF_NUMBER)
#define IS_WS(c,a) (KEYTYPES(c)[CVT(a)] & CONF_WS)
#define IS_ALNUM(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ALNUM)
#define IS_ALNUM_PUNCT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ALNUM_PUNCT)
#define IS_QUOTE(c,a) (KEYTYPES(c)[CVT(a)] & CONF_QUOTE)
#define IS_DQUOTE(c,a) (KEYTYPES(c)[CVT(a)] & CONF_DQUOTE)
#define IS_COMMENT(conf,c) is_keytype(conf, c, CONF_COMMENT)
#define IS_FCOMMENT(conf,c) is_keytype(conf, c, CONF_FCOMMENT)
#define IS_EOF(conf,c) is_keytype(conf, c, CONF_EOF)
#define IS_ESC(conf,c) is_keytype(conf, c, CONF_ESC)
#define IS_NUMBER(conf,c) is_keytype(conf, c, CONF_NUMBER)
#define IS_WS(conf,c) is_keytype(conf, c, CONF_WS)
#define IS_ALNUM(conf,c) is_keytype(conf, c, CONF_ALNUM)
#define IS_ALNUM_PUNCT(conf,c) is_keytype(conf, c, CONF_ALNUM_PUNCT)
#define IS_QUOTE(conf,c) is_keytype(conf, c, CONF_QUOTE)
#define IS_DQUOTE(conf,c) is_keytype(conf, c, CONF_DQUOTE)

static const unsigned short CONF_type_default[128] = {
0x0008, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
Expand Down
27 changes: 10 additions & 17 deletions crypto/conf/keysets.pl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -85,24 +85,17 @@
#define CONF_ALNUM (CONF_ALPHA|CONF_NUMBER|CONF_UNDER)
#define CONF_ALNUM_PUNCT (CONF_ALPHA|CONF_NUMBER|CONF_UNDER|CONF_PUNCT)
#define KEYTYPES(c) ((const unsigned short *)((c)->meth_data))
#ifndef CHARSET_EBCDIC
# define CVT(a) ((a) & 0x7F)
#else
# define CVT(a) os_toascci[(a) & 0x7F]
#endif
#define IS_COMMENT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_COMMENT)
#define IS_FCOMMENT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_FCOMMENT)
#define IS_EOF(c,a) (KEYTYPES(c)[CVT(a)] & CONF_EOF)
#define IS_ESC(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ESC)
#define IS_NUMBER(c,a) (KEYTYPES(c)[CVT(a)] & CONF_NUMBER)
#define IS_WS(c,a) (KEYTYPES(c)[CVT(a)] & CONF_WS)
#define IS_ALNUM(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ALNUM)
#define IS_ALNUM_PUNCT(c,a) (KEYTYPES(c)[CVT(a)] & CONF_ALNUM_PUNCT)
#define IS_QUOTE(c,a) (KEYTYPES(c)[CVT(a)] & CONF_QUOTE)
#define IS_DQUOTE(c,a) (KEYTYPES(c)[CVT(a)] & CONF_DQUOTE)
#define IS_COMMENT(conf,c) is_keytype(conf, c, CONF_COMMENT)
#define IS_FCOMMENT(conf,c) is_keytype(conf, c, CONF_FCOMMENT)
#define IS_EOF(conf,c) is_keytype(conf, c, CONF_EOF)
#define IS_ESC(conf,c) is_keytype(conf, c, CONF_ESC)
#define IS_NUMBER(conf,c) is_keytype(conf, c, CONF_NUMBER)
#define IS_WS(conf,c) is_keytype(conf, c, CONF_WS)
#define IS_ALNUM(conf,c) is_keytype(conf, c, CONF_ALNUM)
#define IS_ALNUM_PUNCT(conf,c) is_keytype(conf, c, CONF_ALNUM_PUNCT)
#define IS_QUOTE(conf,c) is_keytype(conf, c, CONF_QUOTE)
#define IS_DQUOTE(conf,c) is_keytype(conf, c, CONF_DQUOTE)
EOF

Expand Down

0 comments on commit 2994483

Please sign in to comment.