generic-library/openssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

gcm128.c: add CRYPTO_gcm128_[en|de]crypt_ctr32.

Browse Source
This commit is contained in:
Andy Polyakov 2010-08-02 21:39:51 +00:00
parent 30ab7af242
commit f71c6aceeb
2 changed files with 171 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

165
crypto/modes/gcm128.c
View File

@ -1092,6 +1092,171 @@ void CRYPTO_gcm128_decrypt(GCM128_CONTEXT *ctx,
ctx->res = n; ctx->res = n;
} }
void CRYPTO_gcm128_encrypt_crt32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len, ctr128_f stream)
{
const union { long one; char little; } is_endian = {1};
unsigned int n, ctr;
size_t i;
ctx->len.u[1] += len;
n = ctx->res;
if (is_endian.little)
ctr = GETU32(ctx->Yi.c+12);
else
ctr = ctx->Yi.d[3];
if (n) {
while (n && len) {
ctx->Xi.c[n] ^= *(out++) = *(in++)^ctx->EKi.c[n];
--len;
n = (n+1)%16;
}
if (n==0) GCM_MUL(ctx,Xi);
else {
ctx->res = n;
return;
}
}
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
while (len>=GHASH_CHUNK) {
(*stream)(in,out,GHASH_CHUNK/16,ctx->key,ctx->Yi.c);
ctr += GHASH_CHUNK/16;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
GHASH(ctx,out,GHASH_CHUNK);
out += GHASH_CHUNK;
in += GHASH_CHUNK;
len -= GHASH_CHUNK;
}
#endif
if ((i = (len&(size_t)-16))) {
size_t j=i/16;
(*stream)(in,out,j,ctx->key,ctx->Yi.c);
ctr += j;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
in += i;
len -= i;
#if defined(GHASH)
GHASH(ctx,out,i);
out += i;
#else
while (j--) {
for (i=0;i<16;++i) ctx->Xi.c[i] ^= out[i];
GCM_MUL(ctx,Xi);
out += 16;
}
#endif
}
if (len) {
(*ctx->block)(ctx->Yi.c,ctx->EKi.c,ctx->key);
++ctr;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
while (len--) {
ctx->Xi.c[n] ^= out[n] = in[n]^ctx->EKi.c[n];
++n;
}
}
ctx->res = n;
}
void CRYPTO_gcm128_decrypt_ctr32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len,ctr128_f stream)
{
const union { long one; char little; } is_endian = {1};
unsigned int n, ctr;
size_t i;
ctx->len.u[1] += len;
n = ctx->res;
if (is_endian.little)
ctr = GETU32(ctx->Yi.c+12);
else
ctr = ctx->Yi.d[3];
if (n) {
while (n && len) {
u8 c = *(in++);
*(out++) = c^ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
--len;
n = (n+1)%16;
}
if (n==0) GCM_MUL (ctx,Xi);
else {
ctx->res = n;
return;
}
}
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
while (len>=GHASH_CHUNK) {
GHASH(ctx,in,GHASH_CHUNK);
(*stream)(in,out,GHASH_CHUNK/16,ctx->key,ctx->Yi.c);
ctr += GHASH_CHUNK/16;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
out += GHASH_CHUNK;
in += GHASH_CHUNK;
len -= GHASH_CHUNK;
}
#endif
if ((i = (len&(size_t)-16))) {
size_t j=i/16;
#if defined(GHASH)
GHASH(ctx,in,i);
#else
while (j--) {
size_t k;
for (k=0;k<16;++k) ctx->Xi.c[k] ^= in[k];
GCM_MUL(ctx,Xi);
in += 16;
}
j = i/16;
in -= i;
#endif
(*stream)(in,out,j,ctx->key,ctx->Yi.c);
ctr += j;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
out += i;
in += i;
len -= i;
}
if (len) {
(*ctx->block)(ctx->Yi.c,ctx->EKi.c,ctx->key);
++ctr;
if (is_endian.little)
PUTU32(ctx->Yi.c+12,ctr);
else
ctx->Yi.d[3] = ctr;
while (len--) {
u8 c = in[n];
ctx->Xi.c[n] ^= c;
out[n] = c^ctx->EKi.c[n];
++n;
}
}
ctx->res = n;
}
int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx,const unsigned char *tag, int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx,const unsigned char *tag,
size_t len) size_t len)
{ {

6
crypto/modes/modes.h
View File

@ -94,6 +94,12 @@ void CRYPTO_gcm128_encrypt(GCM128_CONTEXT *ctx,
void CRYPTO_gcm128_decrypt(GCM128_CONTEXT *ctx, void CRYPTO_gcm128_decrypt(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out, const unsigned char *in, unsigned char *out,
size_t len); size_t len);
void CRYPTO_gcm128_encrypt_ctr32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len, ctr128_f stream);
void CRYPTO_gcm128_decrypt_ctr32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len, ctr128_f stream);
int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx,const unsigned char *tag, int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx,const unsigned char *tag,
size_t len); size_t len);
void CRYPTO_gcm128_release(GCM128_CONTEXT *ctx); void CRYPTO_gcm128_release(GCM128_CONTEXT *ctx);