Do no try to pretend we're at the end of anything unless we're at the end

[openssl.git] / crypto / evp / bio_enc.c

diff --git a/crypto/evp/bio_enc.c b/crypto/evp/bio_enc.c
index f8336f261087f0b1867262aacf2df514fc2b180c..f6ac94c6e1bba4464a6f6c7239cd42bde6fb9dfc 100644 (file)
--- a/crypto/evp/bio_enc.c
+++ b/crypto/evp/bio_enc.c
@@ -71,7 +71,7 @@ static int enc_new(BIO *h);
 static int enc_free(BIO *data);
 static long enc_callback_ctrl(BIO *h, int cmd, bio_info_cb *fps);
 #define ENC_BLOCK_SIZE (1024*4)
-#define BUF_OFFSET     8 /* XXX: why? */
+#define BUF_OFFSET     (EVP_MAX_BLOCK_LENGTH*2)
 
 typedef struct enc_struct
        {
@@ -81,7 +81,10 @@ typedef struct enc_struct
        int finished;
        int ok;                 /* bad decrypt */
        EVP_CIPHER_CTX cipher;
-       char buf[ENC_BLOCK_SIZE+BUF_OFFSET+2/*why?*/];
+       /* buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate
+        * can return up to a block more data than is presented to it
+        */
+       char buf[ENC_BLOCK_SIZE+BUF_OFFSET+2];
        } BIO_ENC_CTX;
 
 static BIO_METHOD methods_enc=
@@ -107,8 +110,8 @@ static int enc_new(BIO *bi)
        BIO_ENC_CTX *ctx;
 
        ctx=(BIO_ENC_CTX *)OPENSSL_malloc(sizeof(BIO_ENC_CTX));
-       EVP_CIPHER_CTX_init(&ctx->cipher);
        if (ctx == NULL) return(0);
+       EVP_CIPHER_CTX_init(&ctx->cipher);
 
        ctx->buf_len=0;
        ctx->buf_off=0;
@@ -129,7 +132,7 @@ static int enc_free(BIO *a)
        if (a == NULL) return(0);
        b=(BIO_ENC_CTX *)a->ptr;
        EVP_CIPHER_CTX_cleanup(&(b->cipher));
-       memset(a->ptr,0,sizeof(BIO_ENC_CTX));
+       OPENSSL_cleanse(a->ptr,sizeof(BIO_ENC_CTX));
        OPENSSL_free(a->ptr);
        a->ptr=NULL;
        a->init=0;
@@ -171,7 +174,7 @@ static int enc_read(BIO *b, char *out, int outl)
                {
                if (ctx->cont <= 0) break;
 
-               /* read in at offset 8, read the EVP_Cipher
+               /* read in at IV offset, read the EVP_Cipher
                 * documentation about why */
                i=BIO_read(b->next_bio,&(ctx->buf[BUF_OFFSET]),ENC_BLOCK_SIZE);
 
@@ -181,7 +184,7 @@ static int enc_read(BIO *b, char *out, int outl)
                        if (!BIO_should_retry(b->next_bio))
                                {
                                ctx->cont=i;
-                               i=EVP_CipherFinal(&(ctx->cipher),
+                               i=EVP_CipherFinal_ex(&(ctx->cipher),
                                        (unsigned char *)ctx->buf,
                                        &(ctx->buf_len));
                                ctx->ok=i;
@@ -268,7 +271,7 @@ static int enc_write(BIO *b, const char *in, int inl)
                        if (i <= 0)
                                {
                                BIO_copy_next_retry(b);
-                               return(i);
+                               return (ret == inl) ? i : ret - inl;
                                }
                        n-=i;
                        ctx->buf_off+=i;
@@ -295,7 +298,7 @@ static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
        case BIO_CTRL_RESET:
                ctx->ok=1;
                ctx->finished=0;
-               EVP_CipherInit(&(ctx->cipher),NULL,NULL,NULL,
+               EVP_CipherInit_ex(&(ctx->cipher),NULL,NULL,NULL,NULL,
                        ctx->cipher.encrypt);
                ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
                break;
@@ -322,17 +325,14 @@ again:
                        {
                        i=enc_write(b,NULL,0);
                        if (i < 0)
-                               {
-                               ret=i;
-                               break;
-                               }
+                               return i;
                        }
 
                if (!ctx->finished)
                        {
                        ctx->finished=1;
                        ctx->buf_off=0;
-                       ret=EVP_CipherFinal(&(ctx->cipher),
+                       ret=EVP_CipherFinal_ex(&(ctx->cipher),
                                (unsigned char *)ctx->buf,
                                &(ctx->buf_len));
                        ctx->ok=(int)ret;
@@ -405,8 +405,8 @@ EVP_CIPHER_ctx *c;
        }
 */
 
-void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, unsigned char *k,
-            unsigned char *i, int e)
+void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,
+            const unsigned char *i, int e)
        {
        BIO_ENC_CTX *ctx;
 
@@ -418,7 +418,7 @@ void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, unsigned char *k,
 
        b->init=1;
        ctx=(BIO_ENC_CTX *)b->ptr;
-       EVP_CipherInit(&(ctx->cipher),c,k,i,e);
+       EVP_CipherInit_ex(&(ctx->cipher),c,NULL, k,i,e);
        
        if (b->callback != NULL)
                b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,1L);