commit 86477f4e3fedb316e5708f4e7fd09ea61840993a Author: Taylor Yu catalyst@torproject.org Date: Thu Apr 6 15:17:28 2017 -0400
Use baseXX length macros in baseXX_encode()
Use the new baseXX length macros to clean up the length checks in the baseXX_encode() functions. --- src/common/util_format.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/src/common/util_format.c b/src/common/util_format.c index 51b299b..80844af 100644 --- a/src/common/util_format.c +++ b/src/common/util_format.c @@ -28,7 +28,8 @@ size_t base32_encoded_size(size_t srclen) { size_t enclen; - enclen = CEIL_DIV(srclen*8, 5) + 1; + tor_assert(srclen < SIZE_T_CEILING / 8); + enclen = BASE32_NOPAD_BUFSIZE(srclen); tor_assert(enclen < INT_MAX && enclen > srclen); return enclen; } @@ -41,7 +42,6 @@ base32_encode(char *dest, size_t destlen, const char *src, size_t srclen) size_t nbits = srclen * 8; size_t bit;
- tor_assert(srclen < SIZE_T_CEILING/8); /* We need enough space for the encoded data and the extra NUL byte. */ tor_assert(base32_encoded_size(srclen) <= destlen); tor_assert(destlen < SIZE_T_CEILING); @@ -133,6 +133,8 @@ base32_decode(char *dest, size_t destlen, const char *src, size_t srclen) /** Return the Base64 encoded size of <b>srclen</b> bytes of data in * bytes. * + * Does <b>NOT</b> count the terminating NUL. + * * If <b>flags</b>&BASE64_ENCODE_MULTILINE is true, return the size * of the encoded output as multiline output (64 character, `\n' terminated * lines). @@ -141,19 +143,16 @@ size_t base64_encode_size(size_t srclen, int flags) { size_t enclen; + + /* Use INT_MAX for overflow checking because base64_encode() returns int. */ tor_assert(srclen < INT_MAX); + tor_assert(CEIL_DIV(srclen, 3) < INT_MAX / 4);
- if (srclen == 0) - return 0; + enclen = BASE64_LEN(srclen); + if (flags & BASE64_ENCODE_MULTILINE) + enclen += CEIL_DIV(enclen, BASE64_OPENSSL_LINELEN);
- enclen = ((srclen - 1) / 3) * 4 + 4; - if (flags & BASE64_ENCODE_MULTILINE) { - size_t remainder = enclen % BASE64_OPENSSL_LINELEN; - enclen += enclen / BASE64_OPENSSL_LINELEN; - if (remainder) - enclen++; - } - tor_assert(enclen < INT_MAX && enclen > srclen); + tor_assert(enclen < INT_MAX && (enclen == 0 || enclen > srclen)); return enclen; }
@@ -475,7 +474,8 @@ base16_encode(char *dest, size_t destlen, const char *src, size_t srclen) const char *end; char *cp;
- tor_assert(destlen >= srclen*2+1); + tor_assert(srclen < SIZE_T_CEILING / 2 - 1); + tor_assert(destlen >= BASE16_BUFSIZE(srclen)); tor_assert(destlen < SIZE_T_CEILING);
/* Make sure we leave no uninitialized data in the destination buffer. */