Make ctr mode behaviour consistent with other modes.
[openssl.git] / crypto / evp / evp_enc.c
index be0758a87965feeb7b0c0494c3002213cd5571e9..a35621a2ec9d27fc3db44baf9bb499b8711b0e5e 100644 (file)
 #include "cryptlib.h"
 #include <openssl/evp.h>
 #include <openssl/err.h>
+#include <openssl/rand.h>
 #ifndef OPENSSL_NO_ENGINE
 #include <openssl/engine.h>
 #endif
 #include "evp_locl.h"
 
-const char *EVP_version="EVP" OPENSSL_VERSION_PTEXT;
+const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
 
 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
        {
@@ -73,6 +74,13 @@ void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
        /* ctx->cipher=NULL; */
        }
 
+EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
+       {
+       EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
+       if (ctx)
+               EVP_CIPHER_CTX_init(ctx);
+       return ctx;
+       }
 
 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
             const unsigned char *key, const unsigned char *iv, int enc)
@@ -116,7 +124,7 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *imp
                        {
                        if (!ENGINE_init(impl))
                                {
-                               EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
+                               EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
                                return 0;
                                }
                        }
@@ -133,7 +141,7 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *imp
                                 * control history, is that we should at least
                                 * be able to avoid using US mispellings of
                                 * "initialisation"? */
-                               EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
+                               EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
                                return 0;
                                }
                        /* We'll use the ENGINE's private cipher definition */
@@ -148,21 +156,33 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *imp
 #endif
 
                ctx->cipher=cipher;
-               ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
+               if (ctx->cipher->ctx_size)
+                       {
+                       ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
+                       if (!ctx->cipher_data)
+                               {
+                               EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
+                               return 0;
+                               }
+                       }
+               else
+                       {
+                       ctx->cipher_data = NULL;
+                       }
                ctx->key_len = cipher->key_len;
                ctx->flags = 0;
                if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)
                        {
                        if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))
                                {
-                               EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
+                               EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
                                return 0;
                                }
                        }
                }
        else if(!ctx->cipher)
                {
-               EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_NO_CIPHER_SET);
+               EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
                return 0;
                }
 #ifndef OPENSSL_NO_ENGINE
@@ -186,10 +206,14 @@ skip_to_init:
                        ctx->num = 0;
 
                        case EVP_CIPH_CBC_MODE:
+                       case EVP_CIPH_CTR_MODE:
 
-                       OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <= sizeof ctx->iv);
+                       OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
+                                       (int)sizeof(ctx->iv));
                        if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
-                       memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
+                       /* Don't reuse IV for CTR mode */
+                       if (EVP_CIPHER_CTX_mode(ctx) != EVP_CIPH_CTR_MODE)
+                               memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
                        break;
 
                        default:
@@ -258,7 +282,12 @@ int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
        {
        int i,j,bl;
 
-       OPENSSL_assert(inl > 0);
+       if (inl <= 0)
+               {
+               *outl = 0;
+               return inl == 0;
+               }
+
        if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
                {
                if(ctx->cipher->do_cipher(ctx,out,in,inl))
@@ -274,7 +303,7 @@ int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
                }
        i=ctx->buf_len;
        bl=ctx->cipher->block_size;
-       OPENSSL_assert(bl <= sizeof ctx->buf);
+       OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
        if (i != 0)
                {
                if (i+inl < bl)
@@ -320,7 +349,8 @@ int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 
 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
        {
-       int i,n,b,bl,ret;
+       int n,ret;
+       unsigned int i, b, bl;
 
        b=ctx->cipher->block_size;
        OPENSSL_assert(b <= sizeof ctx->buf);
@@ -334,7 +364,7 @@ int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
                {
                if(bl)
                        {
-                       EVPerr(EVP_F_EVP_ENCRYPTFINAL,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
+                       EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
                        return 0;
                        }
                *outl = 0;
@@ -356,12 +386,13 @@ int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
             const unsigned char *in, int inl)
        {
-       int b, fix_len;
+       int fix_len;
+       unsigned int b;
 
-       if (inl == 0)
+       if (inl <= 0)
                {
-               *outl=0;
-               return 1;
+               *outl = 0;
+               return inl == 0;
                }
 
        if (ctx->flags & EVP_CIPH_NO_PADDING)
@@ -409,8 +440,8 @@ int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 
 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
        {
-       int i,b;
-       int n;
+       int i,n;
+       unsigned int b;
 
        *outl=0;
        b=ctx->cipher->block_size;
@@ -418,7 +449,7 @@ int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
                {
                if(ctx->buf_len)
                        {
-                       EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
+                       EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
                        return 0;
                        }
                *outl = 0;
@@ -428,21 +459,21 @@ int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
                {
                if (ctx->buf_len || !ctx->final_used)
                        {
-                       EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
+                       EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
                        return(0);
                        }
                OPENSSL_assert(b <= sizeof ctx->final);
                n=ctx->final[b-1];
-               if (n b)
+               if (n == 0 || n > (int)b)
                        {
-                       EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT);
+                       EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
                        return(0);
                        }
                for (i=0; i<n; i++)
                        {
                        if (ctx->final[--b] != n)
                                {
-                               EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT);
+                               EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
                                return(0);
                                }
                        }
@@ -456,6 +487,15 @@ int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
        return(1);
        }
 
+void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
+       {
+       if (ctx)
+               {
+               EVP_CIPHER_CTX_cleanup(ctx);
+               OPENSSL_free(ctx);
+               }
+       }
+
 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
        {
        if (c->cipher != NULL)
@@ -519,3 +559,48 @@ int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
        }
        return ret;
 }
+
+int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
+       {
+       if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
+               return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
+       if (RAND_bytes(key, ctx->key_len) <= 0)
+               return 0;
+       return 1;
+       }
+
+int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
+       {
+       if ((in == NULL) || (in->cipher == NULL))
+               {
+               EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,EVP_R_INPUT_NOT_INITIALIZED);
+               return 0;
+               }
+#ifndef OPENSSL_NO_ENGINE
+       /* Make sure it's safe to copy a cipher context using an ENGINE */
+       if (in->engine && !ENGINE_init(in->engine))
+               {
+               EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_ENGINE_LIB);
+               return 0;
+               }
+#endif
+
+       EVP_CIPHER_CTX_cleanup(out);
+       memcpy(out,in,sizeof *out);
+
+       if (in->cipher_data && in->cipher->ctx_size)
+               {
+               out->cipher_data=OPENSSL_malloc(in->cipher->ctx_size);
+               if (!out->cipher_data)
+                       {
+                       EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_MALLOC_FAILURE);
+                       return 0;
+                       }
+               memcpy(out->cipher_data,in->cipher_data,in->cipher->ctx_size);
+               }
+
+       if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
+               return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);
+       return 1;
+       }
+