1 files changed, 27 insertions, 3 deletions

diff --git a/src/lib/libcrypto/evp/bio_enc.c b/src/lib/libcrypto/evp/bio_enc.c
index 0a7b1ecf07..629bf4b95d 100644
--- a/src/lib/libcrypto/evp/bio_enc.c
+++ b/src/lib/libcrypto/evp/bio_enc.c
@@ -69,6 +69,7 @@ static int enc_read(BIO *h,char *buf,int size);
 static long enc_ctrl(BIO *h,int cmd,long arg1,char *arg2);
 static int enc_new(BIO *h);
 static int enc_free(BIO *data);
+static long enc_callback_ctrl(BIO *h,int cmd,void (*fp)());
 #define ENC_BLOCK_SIZE  (1024*4)
 
 typedef struct enc_struct
@@ -92,6 +93,7 @@ static BIO_METHOD methods_enc=
         enc_ctrl,
         enc_new,
         enc_free,
+        enc_callback_ctrl,
         };
 
 BIO_METHOD *BIO_f_cipher(void)
@@ -184,9 +186,11 @@ static int enc_read(BIO *b, char *out, int outl)
                                 ctx->ok=i;
                                 ctx->buf_off=0;
                                 }
-                        else
+                        else 
+                                {
                                 ret=(ret == 0)?i:ret;
-                        break;
+                                break;
+                                }
                         }
                 else
                         {
@@ -194,13 +198,19 @@ static int enc_read(BIO *b, char *out, int outl)
                                 (unsigned char *)ctx->buf,&ctx->buf_len,
                                 (unsigned char *)&(ctx->buf[8]),i);
                         ctx->cont=1;
+                        /* Note: it is possible for EVP_CipherUpdate to
+                         * decrypt zero bytes because this is or looks like
+                         * the final block: if this happens we should retry
+                         * and either read more data or decrypt the final
+                         * block
+                         */
+                        if(ctx->buf_len == 0) continue;
                         }
 
                 if (ctx->buf_len <= outl)
                         i=ctx->buf_len;
                 else
                         i=outl;
-
                 if (i <= 0) break;
                 memcpy(out,ctx->buf,i);
                 ret+=i;
@@ -360,6 +370,20 @@ again:
         return(ret);
         }
 
+static long enc_callback_ctrl(BIO *b, int cmd, void (*fp)())
+        {
+        long ret=1;
+
+        if (b->next_bio == NULL) return(0);
+        switch (cmd)
+                {
+        default:
+                ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
+                break;
+                }
+        return(ret);
+        }
+
 /*
 void BIO_set_cipher_ctx(b,c)
 BIO *b;