-/*
- * Simplified version of padlock_aes_cipher() used when
- * 1) both input and output buffers are at aligned addresses.
- * or when
- * 2) running on a newer CPU that doesn't require aligned buffers.
- */
-static int
-padlock_aes_cipher_omnivorous(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
- const unsigned char *in_arg, size_t nbytes)
-{
- struct padlock_cipher_data *cdata;
- void *iv;
-
- cdata = ALIGNED_CIPHER_DATA(ctx);
- padlock_verify_context(cdata);
-
- switch (EVP_CIPHER_CTX_mode(ctx)) {
- case EVP_CIPH_ECB_MODE:
- padlock_xcrypt_ecb(nbytes/AES_BLOCK_SIZE, cdata, out_arg, in_arg);
- break;
-
- case EVP_CIPH_CBC_MODE:
- memcpy(cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- iv = padlock_xcrypt_cbc(nbytes/AES_BLOCK_SIZE, cdata, out_arg, in_arg);
- memcpy(ctx->iv, iv, AES_BLOCK_SIZE);
- break;
-
- case EVP_CIPH_CFB_MODE:
- memcpy(cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- iv = padlock_xcrypt_cfb(nbytes/AES_BLOCK_SIZE, cdata, out_arg, in_arg);
- memcpy(ctx->iv, iv, AES_BLOCK_SIZE);
- break;
-
- case EVP_CIPH_OFB_MODE:
- memcpy(cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- padlock_xcrypt_ofb(nbytes/AES_BLOCK_SIZE, cdata, out_arg, in_arg);
- memcpy(ctx->iv, cdata->iv, AES_BLOCK_SIZE);
- break;
-
- default:
- return 0;
- }
-
- memset(cdata->iv, 0, AES_BLOCK_SIZE);
-
- return 1;
-}
-
-#ifndef PADLOCK_CHUNK
-# define PADLOCK_CHUNK 512 /* Must be a power of 2 larger than 16 */
-#endif
-#if PADLOCK_CHUNK<16 || PADLOCK_CHUNK&(PADLOCK_CHUNK-1)
-# error "insane PADLOCK_CHUNK..."
-#endif
-
-/* Re-align the arguments to 16-Bytes boundaries and run the
- encryption function itself. This function is not AES-specific. */
-static int
-padlock_aes_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
- const unsigned char *in_arg, size_t nbytes)
-{
- struct padlock_cipher_data *cdata;
- const void *inp;
- unsigned char *out;
- void *iv;
- int inp_misaligned, out_misaligned, realign_in_loop;
- size_t chunk, allocated=0;
-
- /* ctx->num is maintained in byte-oriented modes,
- such as CFB and OFB... */
- if ((chunk = ctx->num)) { /* borrow chunk variable */
- unsigned char *ivp=ctx->iv;
-
- switch (EVP_CIPHER_CTX_mode(ctx)) {
- case EVP_CIPH_CFB_MODE:
- if (chunk >= AES_BLOCK_SIZE)
- return 0; /* bogus value */
-
- if (ctx->encrypt)
- while (chunk<AES_BLOCK_SIZE && nbytes!=0) {
- ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
- chunk++, nbytes--;
- }
- else while (chunk<AES_BLOCK_SIZE && nbytes!=0) {
- unsigned char c = *(in_arg++);
- *(out_arg++) = c ^ ivp[chunk];
- ivp[chunk++] = c, nbytes--;
- }
-
- ctx->num = chunk%AES_BLOCK_SIZE;
- break;
- case EVP_CIPH_OFB_MODE:
- if (chunk >= AES_BLOCK_SIZE)
- return 0; /* bogus value */
-
- while (chunk<AES_BLOCK_SIZE && nbytes!=0) {
- *(out_arg++) = *(in_arg++) ^ ivp[chunk];
- chunk++, nbytes--;
- }
-
- ctx->num = chunk%AES_BLOCK_SIZE;
- break;
- }
- }
-
- if (nbytes == 0)
- return 1;
-#if 0
- if (nbytes % AES_BLOCK_SIZE)
- return 0; /* are we expected to do tail processing? */
-#else
- /* nbytes is always multiple of AES_BLOCK_SIZE in ECB and CBC
- modes and arbitrary value in byte-oriented modes, such as
- CFB and OFB... */
-#endif
-
- /* VIA promises CPUs that won't require alignment in the future.
- For now padlock_aes_align_required is initialized to 1 and
- the condition is never met... */
- /* C7 core is capable to manage unaligned input in non-ECB[!]
- mode, but performance penalties appear to be approximately
- same as for software alignment below or ~3x. They promise to
- improve it in the future, but for now we can just as well
- pretend that it can only handle aligned input... */
- if (!padlock_aes_align_required && (nbytes%AES_BLOCK_SIZE)==0)
- return padlock_aes_cipher_omnivorous(ctx, out_arg, in_arg, nbytes);
-
- inp_misaligned = (((size_t)in_arg) & 0x0F);
- out_misaligned = (((size_t)out_arg) & 0x0F);
-
- /* Note that even if output is aligned and input not,
- * I still prefer to loop instead of copy the whole
- * input and then encrypt in one stroke. This is done
- * in order to improve L1 cache utilization... */
- realign_in_loop = out_misaligned|inp_misaligned;
-
- if (!realign_in_loop && (nbytes%AES_BLOCK_SIZE)==0)
- return padlock_aes_cipher_omnivorous(ctx, out_arg, in_arg, nbytes);
-
- /* this takes one "if" out of the loops */
- chunk = nbytes;
- chunk %= PADLOCK_CHUNK;
- if (chunk==0) chunk = PADLOCK_CHUNK;
-
- if (out_misaligned) {
- /* optmize for small input */
- allocated = (chunk<nbytes?PADLOCK_CHUNK:nbytes);
- out = alloca(0x10 + allocated);
- out = NEAREST_ALIGNED(out);
- }
- else
- out = out_arg;
-
- cdata = ALIGNED_CIPHER_DATA(ctx);
- padlock_verify_context(cdata);
-
- switch (EVP_CIPHER_CTX_mode(ctx)) {
- case EVP_CIPH_ECB_MODE:
- do {
- if (inp_misaligned)
- inp = padlock_memcpy(out, in_arg, chunk);
- else
- inp = in_arg;
- in_arg += chunk;
-
- padlock_xcrypt_ecb(chunk/AES_BLOCK_SIZE, cdata, out, inp);
-
- if (out_misaligned)
- out_arg = padlock_memcpy(out_arg, out, chunk) + chunk;
- else
- out = out_arg+=chunk;
-
- nbytes -= chunk;
- chunk = PADLOCK_CHUNK;
- } while (nbytes);
- break;
-
- case EVP_CIPH_CBC_MODE:
- memcpy(cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- goto cbc_shortcut;
- do {
- if (iv != cdata->iv)
- memcpy(cdata->iv, iv, AES_BLOCK_SIZE);
- chunk = PADLOCK_CHUNK;
- cbc_shortcut: /* optimize for small input */
- if (inp_misaligned)
- inp = padlock_memcpy(out, in_arg, chunk);
- else
- inp = in_arg;
- in_arg += chunk;
-
- iv = padlock_xcrypt_cbc(chunk/AES_BLOCK_SIZE, cdata, out, inp);
-
- if (out_misaligned)
- out_arg = padlock_memcpy(out_arg, out, chunk) + chunk;
- else
- out = out_arg+=chunk;
-
- } while (nbytes -= chunk);
- memcpy(ctx->iv, iv, AES_BLOCK_SIZE);
- break;
-
- case EVP_CIPH_CFB_MODE:
- memcpy (iv = cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- chunk &= ~(AES_BLOCK_SIZE-1);
- if (chunk) goto cfb_shortcut;
- else goto cfb_skiploop;
- do {
- if (iv != cdata->iv)
- memcpy(cdata->iv, iv, AES_BLOCK_SIZE);
- chunk = PADLOCK_CHUNK;
- cfb_shortcut: /* optimize for small input */
- if (inp_misaligned)
- inp = padlock_memcpy(out, in_arg, chunk);
- else
- inp = in_arg;
- in_arg += chunk;
-
- iv = padlock_xcrypt_cfb(chunk/AES_BLOCK_SIZE, cdata, out, inp);
-
- if (out_misaligned)
- out_arg = padlock_memcpy(out_arg, out, chunk) + chunk;
- else
- out = out_arg+=chunk;
-
- nbytes -= chunk;
- } while (nbytes >= AES_BLOCK_SIZE);
-
- cfb_skiploop:
- if (nbytes) {
- unsigned char *ivp = cdata->iv;
-
- if (iv != ivp) {
- memcpy(ivp, iv, AES_BLOCK_SIZE);
- iv = ivp;
- }
- ctx->num = nbytes;
- if (cdata->cword.b.encdec) {
- cdata->cword.b.encdec=0;
- padlock_reload_key();
- padlock_xcrypt_ecb(1,cdata,ivp,ivp);
- cdata->cword.b.encdec=1;
- padlock_reload_key();
- while(nbytes) {
- unsigned char c = *(in_arg++);
- *(out_arg++) = c ^ *ivp;
- *(ivp++) = c, nbytes--;
- }
- }
- else { padlock_reload_key();
- padlock_xcrypt_ecb(1,cdata,ivp,ivp);
- padlock_reload_key();
- while (nbytes) {
- *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
- ivp++, nbytes--;
- }
- }
- }
-
- memcpy(ctx->iv, iv, AES_BLOCK_SIZE);
- break;
-
- case EVP_CIPH_OFB_MODE:
- memcpy(cdata->iv, ctx->iv, AES_BLOCK_SIZE);
- chunk &= ~(AES_BLOCK_SIZE-1);
- if (chunk) do {
- if (inp_misaligned)
- inp = padlock_memcpy(out, in_arg, chunk);
- else
- inp = in_arg;
- in_arg += chunk;
-
- padlock_xcrypt_ofb(chunk/AES_BLOCK_SIZE, cdata, out, inp);
-
- if (out_misaligned)
- out_arg = padlock_memcpy(out_arg, out, chunk) + chunk;
- else
- out = out_arg+=chunk;
-
- nbytes -= chunk;
- chunk = PADLOCK_CHUNK;
- } while (nbytes >= AES_BLOCK_SIZE);
-
- if (nbytes) {
- unsigned char *ivp = cdata->iv;
-
- ctx->num = nbytes;
- padlock_reload_key(); /* empirically found */
- padlock_xcrypt_ecb(1,cdata,ivp,ivp);
- padlock_reload_key(); /* empirically found */
- while (nbytes) {
- *(out_arg++) = *(in_arg++) ^ *ivp;
- ivp++, nbytes--;
- }
- }
-
- memcpy(ctx->iv, cdata->iv, AES_BLOCK_SIZE);
- break;
-
- default:
- return 0;
- }
-
- /* Clean the realign buffer if it was used */
- if (out_misaligned) {
- volatile unsigned long *p=(void *)out;
- size_t n = allocated/sizeof(*p);
- while (n--) *p++=0;
- }
-
- memset(cdata->iv, 0, AES_BLOCK_SIZE);
-
- return 1;
-}
-