From c148d7097811c18f277a8559753c770f4ff85771 Mon Sep 17 00:00:00 2001 From: Ben Laurie Date: Mon, 9 Jul 2001 21:00:36 +0000 Subject: [PATCH] A better compromise between encrypt and decrypt (but why isn't it as fast for encrypt?). --- CHANGES | 4 +-- crypto/evp/evp.h | 3 ++ crypto/evp/evp_enc.c | 80 +++++++++++++++++++------------------------- 3 files changed, 39 insertions(+), 48 deletions(-) diff --git a/CHANGES b/CHANGES index 78a894d443..e7d773f862 100644 --- a/CHANGES +++ b/CHANGES @@ -24,9 +24,9 @@ des-cbc 3480.74k 5068.76k 5510.34k 5609.87k 5635.52k des-cbc 3483.72k 5067.62k 5504.60k 5708.01k 5724.80k After: encrypt -des-cbc 4581.64k 5666.39k 5811.23k 5871.60k 5833.23k +des-cbc 4660.16k 5650.19k 5807.19k 5827.13k 5783.32k decrypt -des-cbc 3615.18k 5102.53k 5501.58k 5631.13k 5635.52k +des-cbc 3624.96k 5258.21k 5530.91k 5624.30k 5628.26k [Ben Laurie] *) Fix crypto/bn/asm/mips3.s. diff --git a/crypto/evp/evp.h b/crypto/evp/evp.h index ecd221fb06..04cb709c8f 100644 --- a/crypto/evp/evp.h +++ b/crypto/evp/evp.h @@ -455,6 +455,9 @@ struct evp_cipher_ctx_st RIJNDAEL_KEY rijndael; #endif } c; + int final_used; + int block_mask; + unsigned char final[EVP_MAX_BLOCK_LENGTH];/* possible final block */ }; typedef struct evp_Encode_Ctx_st diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c index d723d095c1..9a7a553bef 100644 --- a/crypto/evp/evp_enc.c +++ b/crypto/evp/evp_enc.c @@ -125,6 +125,8 @@ int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, } if(enc != -1) ctx->encrypt=enc; ctx->buf_len=0; + ctx->final_used=0; + ctx->block_mask=ctx->cipher->block_size-1; return 1; } @@ -160,14 +162,7 @@ int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, { int i,j,bl; - i=ctx->buf_len; - bl=ctx->cipher->block_size; - if ((inl == 0) && (i != bl)) - { - *outl=0; - return 1; - } - if(i == 0 && (inl&(bl-1)) == 0) + if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0) { if(ctx->cipher->do_cipher(ctx,out,in,inl)) { @@ -180,24 +175,26 @@ int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, return 0; } } - *outl=0; + i=ctx->buf_len; + bl=ctx->cipher->block_size; if (i != 0) { if (i+inl < bl) { memcpy(&(ctx->buf[i]),in,inl); ctx->buf_len+=inl; + *outl=0; return 1; } else { j=bl-i; - if (j != 0) memcpy(&(ctx->buf[i]),in,j); + memcpy(&(ctx->buf[i]),in,j); if(!ctx->cipher->do_cipher(ctx,out,ctx->buf,bl)) return 0; inl-=j; in+=j; out+=bl; - *outl+=bl; + *outl=bl; } } i=inl&(bl-1); @@ -246,48 +243,42 @@ int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, unsigned char *in, int inl) { - int b,bl,n; - int keep_last=0; + int b; - *outl=0; - if (inl == 0) return 1; + if (inl == 0) + { + *outl=0; + return 1; + } if (ctx->flags & EVP_CIPH_NO_PADDING) return EVP_EncryptUpdate(ctx, out, outl, in, inl); b=ctx->cipher->block_size; - if (b > 1) + if(ctx->final_used) { - /* Is the input a multiple of the block size? */ - bl=ctx->buf_len; - n=inl+bl; - if (n%b == 0) - { - if (inl < b) /* must be 'just one' buff */ - { - memcpy(&(ctx->buf[bl]),in,inl); - ctx->buf_len=b; - *outl=0; - return 1; - } - keep_last=1; - inl-=b; /* don't do the last block */ - } + memcpy(out,ctx->final,b); + out+=b; } - if(!EVP_EncryptUpdate(ctx,out,outl,in,inl)) return 0; + + if(!EVP_EncryptUpdate(ctx,out,outl,in,inl)) + return 0; /* if we have 'decrypted' a multiple of block size, make sure * we have a copy of this last block */ - if (keep_last) + if (b > 1 && !ctx->buf_len) { - memcpy(&(ctx->buf[0]),&(in[inl]),b); -#ifdef DEBUG - if (ctx->buf_len != 0) + if(!ctx->final_used) { - abort(); + *outl-=b; + ctx->final_used=1; } -#endif - ctx->buf_len=b; + memcpy(ctx->final,&out[*outl],b); + } + else if(ctx->final_used) + { + ctx->final_used=0; + *outl+=b; } return 1; } @@ -311,15 +302,12 @@ int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) } if (b > 1) { - if (ctx->buf_len != b) + if (ctx->buf_len || !ctx->final_used) { EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_WRONG_FINAL_BLOCK_LENGTH); return(0); } - if(!EVP_EncryptUpdate(ctx,ctx->buf,&n,ctx->buf,0)) return 0; - if (n != b) - return(0); - n=ctx->buf[b-1]; + n=ctx->final[b-1]; if (n > b) { EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT); @@ -327,7 +315,7 @@ int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) } for (i=0; ibuf[--b] != n) + if (ctx->final[--b] != n) { EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT); return(0); @@ -335,7 +323,7 @@ int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) } n=ctx->cipher->block_size-n; for (i=0; ibuf[i]; + out[i]=ctx->final[i]; *outl=n; } else -- 2.34.1