Tweaks to SHA-1 update and finalization code.

This commit is contained in:
Stephen Heumann 2017-07-01 14:27:25 -05:00
parent 8b17a15ada
commit 0ad5d39f07

34
sha1.cc
View File

@ -17,13 +17,21 @@ void sha1_update(struct sha1_context *context,
unsigned long length)
{
unsigned int extra = context->extra;
unsigned long oldlength = context->length;
context->length += length;
if ((context->length += length) < oldlength)
context->length2++;
if (extra > 0) {
if (length >= 64 - extra) {
memcpy(&context->chunk[extra], data, 64 - extra);
sha1_processchunk(context);
asm {
phd
lda context
tcd
jsl SHA1_PROCESSCHUNK
pld
}
length -= 64 - extra;
data += 64 - extra;
} else {
@ -35,7 +43,13 @@ void sha1_update(struct sha1_context *context,
while (length >= 64) {
memcpy(&context->chunk, data, 64);
sha1_processchunk(context);
asm {
phd
lda context
tcd
jsl SHA1_PROCESSCHUNK
pld
}
length -= 64;
data += 64;
}
@ -54,16 +68,22 @@ void sha1_finalize(struct sha1_context *context)
memset(&context->chunk[extra], 0, 64 - extra);
if (extra > 64 - 8) {
sha1_processchunk(context);
memset(&context->chunk, 0, 64);
asm {
phd
lda context
tcd
jsl SHA1_PROCESSCHUNK
pld
}
memset(&context->chunk, 0, 64 - 8);
}
/* Append total length in bits */
asm {
phd
lda context
tcd
/* Append total length in bits */
asl length_offset
rol length_offset+2
rol length_offset+4
@ -90,8 +110,10 @@ void sha1_finalize(struct sha1_context *context)
xba
sta data_offset+62
/* Process final block */
jsl SHA1_PROCESSCHUNK
/* Flip hash state words to big-endian order */
lda hash_offset
xba
tay