Kostya Shishkov <[email protected]> writes:

> On Sun, Jul 01, 2012 at 03:16:22PM +0100, Måns Rullgård wrote:
>> Kostya Shishkov <[email protected]> writes:
>> 
>> > On Sun, Jul 01, 2012 at 04:03:00PM +0200, Samuel Pitoiset wrote:
>> >> +void av_xtea_encrypt(AVXTEA *x, uint8_t *dst, const uint8_t *src, int 
>> >> count)
>> >> +{
>> >> +    uint32_t v0, v1, sum = 0, delta = 0x9E3779B9;
>> >> +    int i;
>> >> +
>> >> +    while (count-- > 0) {
>> >> +        v0 = AV_RB32(src);
>> >> +        v1 = AV_RB32(src + 4);
>> >> +
>> >> +        for (i = 0; i < 32; i++) {
>> >> +            v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + x->key[sum & 
>> >> 3]);
>> >> +            sum += delta;
>> >> +            v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + x->key[(sum >> 
>> >> 11) & 3]);
>> >> +        }
>> >> +
>> >> +        AV_WB32(dst, v0);
>> >> +        AV_WB32(dst + 4, v1);
>> >> +
>> >> +        src++;
>> >> +        dst++;
>> >
>> > it should be incremented by 8
>> 
>> And 'count' should be decremented by 8.  It also needs to handle input
>> not a multiple of 8 bytes in length.  Is zero-padding the proper thing
>> to do?
>
> Maybe, but because block bytes are permuted, output length should be multiple
> of eight in any case.

Then document that the output buffer must be able to hold the aligned
size.

-- 
Måns Rullgård
[email protected]
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