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authorStoian Ivanov <s.ivanov@teracomm.bg>2017-12-05 13:27:53 +0100
committerStoian Ivanov <s.ivanov@teracomm.bg>2017-12-05 13:29:19 +0100
commit1e86fddb216b05b3de59bb59db5808f0a0861466 (patch)
tree4e4b2ab4ed567b048a65100bfb5ddd94bfa2544c /aes.c
parentmake thead safe via context pram; remove padding as non working; opitmise abit (diff)
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Diffstat (limited to 'aes.c')
-rw-r--r--aes.c68
1 files changed, 31 insertions, 37 deletions
diff --git a/aes.c b/aes.c
index c42620b..030e8b1 100644
--- a/aes.c
+++ b/aes.c
@@ -482,21 +482,16 @@ static void InvCipher(state_t *state,uint8_t*RoundKey)
#if defined(ECB) && (ECB == 1)
-void AES_ECB_encrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t* output)
+void AES_ECB_encrypt(struct AES_ctx *ctx,const uint8_t* buf)
{
- // Copy input to output, and work in-memory on output
- memcpy(output, input, AES_BLOCKLEN);
-
// The next function call encrypts the PlainText with the Key using AES algorithm.
- Cipher((state_t*)output,ctx->RoundKey);
+ Cipher((state_t*)buf,ctx->RoundKey);
}
-void AES_ECB_decrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t *output)
+void AES_ECB_decrypt(struct AES_ctx *ctx,const uint8_t* buf)
{
- // Copy input to output, and work in-memory on output
- memcpy(output, input, AES_BLOCKLEN);
-
- InvCipher((state_t*)output,ctx->RoundKey);
+ // The next function call decrypts the PlainText with the Key using AES algorithm.
+ InvCipher((state_t*)buf,ctx->RoundKey);
}
@@ -518,35 +513,33 @@ static void XorWithIv(uint8_t* buf,uint8_t*Iv)
}
}
-void AES_CBC_encrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
+void AES_CBC_encrypt_buffer(struct AES_ctx *ctx,uint8_t* buf, uint32_t length)
{
uintptr_t i;
uint8_t *Iv=ctx->Iv;
- memcpy(output, input, length);
for (i = 0; i < length; i += AES_BLOCKLEN)
{
- XorWithIv(output,Iv);
- Cipher((state_t*)output,ctx->RoundKey);
- Iv = output;
- output += AES_BLOCKLEN;
+ XorWithIv(buf,Iv);
+ Cipher((state_t*)buf,ctx->RoundKey);
+ Iv = buf;
+ buf += AES_BLOCKLEN;
//printf("Step %d - %d", i/16, i);
}
//store Iv in ctx for next call
memcpy(ctx->Iv,Iv,AES_BLOCKLEN);
}
-void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input, uint32_t length)
+void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* buf, uint32_t length)
{
uintptr_t i;
- uint8_t *Iv=ctx->Iv;
- memcpy(output, input, length);
+ uint8_t storeNextIv[AES_BLOCKLEN];
for (i = 0; i < length; i += AES_BLOCKLEN)
{
- InvCipher((state_t*)output,ctx->RoundKey);
- XorWithIv(output,Iv);
- Iv = input; //we DO need original input stored here
- input += AES_BLOCKLEN;
- output += AES_BLOCKLEN;
+ memcpy(storeNextIv, buf, AES_BLOCKLEN);
+ InvCipher((state_t*)buf,ctx->RoundKey);
+ XorWithIv(buf,ctx->Iv);
+ memcpy(ctx->Iv, storeNextIv, AES_BLOCKLEN);
+ buf += AES_BLOCKLEN;
}
}
@@ -558,34 +551,35 @@ void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input
#if defined(CTR) && (CTR == 1)
/* Symmetrical operation: same function for encrypting as for decrypting. Note any IV/nonce should never be reused with the same key */
-void AES_CTR_xcrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
+void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, uint32_t length)
{
uint8_t buffer[AES_BLOCKLEN];
- int j;
unsigned i;
- for (i = 0; i < length; ++i)
+ int bi;
+ for (i = 0,bi=AES_BLOCKLEN; i < length; ++i,bi++)
{
- if ((i & (AES_BLOCKLEN - 1)) == 0) //we need to regen xor compliment in buff
+ if (bi == AES_BLOCKLEN) //we need to regen xor compliment in buffer
{
memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
Cipher((state_t*)buffer,ctx->RoundKey);
- /* Increment counter and handle overflow */
- for (j = (AES_BLOCKLEN - 1); j >= 0; --j)
+ /* Increment Iv and handle overflow */
+ for (bi = (AES_BLOCKLEN - 1); bi >= 0; --bi)
{
- ctx->Iv[j] += 1;
+ if (ctx->Iv[bi] == 255) { //inc will owerflow
+ ctx->Iv[bi]=0;
+ continue;
+ }
+ ctx->Iv[bi] += 1;
+ break;
- /* Break if no overflow, keep going otherwise */
- if (ctx->Iv[j] != 0)
- {
- break;
- }
}
+ bi=0;
}
- output[i] = (input[i] ^ buffer[(i & (AES_BLOCKLEN - 1))]);
+ buf[i] = (buf[i] ^ buffer[bi]);
}
}