diff options
Diffstat (limited to 'src/common')
-rw-r--r-- | src/common/util_format.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/src/common/util_format.c b/src/common/util_format.c index e40fe30680..009db7bc73 100644 --- a/src/common/util_format.c +++ b/src/common/util_format.c @@ -515,18 +515,21 @@ hex_decode_digit(char c) return hex_decode_digit_(c); } -/** Given a hexadecimal string of <b>srclen</b> bytes in <b>src</b>, decode it - * and store the result in the <b>destlen</b>-byte buffer at <b>dest</b>. - * Return 0 on success, -1 on failure. */ +/** Given a hexadecimal string of <b>srclen</b> bytes in <b>src</b>, decode + * it and store the result in the <b>destlen</b>-byte buffer at <b>dest</b>. + * Return the number of bytes decoded on success, -1 on failure. If + * <b>destlen</b> is greater than INT_MAX or less than half of + * <b>srclen</b>, -1 is returned. */ int base16_decode(char *dest, size_t destlen, const char *src, size_t srclen) { const char *end; - + char *dest_orig = dest; int v1,v2; + if ((srclen % 2) != 0) return -1; - if (destlen < srclen/2 || destlen > SIZE_T_CEILING) + if (destlen < srclen/2 || destlen > INT_MAX) return -1; memset(dest, 0, destlen); @@ -541,6 +544,9 @@ base16_decode(char *dest, size_t destlen, const char *src, size_t srclen) ++dest; src+=2; } - return 0; + + tor_assert((dest-dest_orig) <= (ptrdiff_t) destlen); + + return (int) (dest-dest_orig); } |