RT4129: BUF_new_mem_buf should take const void *

Signed-off-by: NRich Salz <rsalz@akamai.com>
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

crypto/bio/bss_mem.c

@@ -108,7 +108,7 @@ BIO_METHOD *BIO_s_secmem(void)
     return(&secmem_method);
 }
 
-BIO *BIO_new_mem_buf(void *buf, int len)
+BIO *BIO_new_mem_buf(const void *buf, int len)
 {
     BIO *ret;
     BUF_MEM *b;
@@ -122,7 +122,8 @@ BIO *BIO_new_mem_buf(void *buf, int len)
     if ((ret = BIO_new(BIO_s_mem())) == NULL)
         return NULL;
     b = (BUF_MEM *)ret->ptr;
-    b->data = buf;
+    /* Cast away const and trust in the MEM_RDONLY flag. */
+    b->data = (void *)buf;
     b->length = sz;
     b->max = sz;
     ret->flags |= BIO_FLAGS_MEM_RDONLY;

doc/crypto/BIO_s_mem.pod

@@ -17,7 +17,7 @@ BIO_get_mem_ptr, BIO_new_mem_buf - memory BIO
  BIO_set_mem_buf(BIO *b,BUF_MEM *bm,int c)
  BIO_get_mem_ptr(BIO *b,BUF_MEM **pp)
 
- BIO *BIO_new_mem_buf(void *buf, int len);
+ BIO *BIO_new_mem_buf(const void *buf, int len);
 
 =head1 DESCRIPTION
 
@@ -65,7 +65,7 @@ BIO_get_mem_ptr() places the underlying BUF_MEM structure in B<pp>. It is
 a macro.
 
 BIO_new_mem_buf() creates a memory BIO using B<len> bytes of data at B<buf>,
-if B<len> is -1 then the B<buf> is assumed to be null terminated and its
+if B<len> is -1 then the B<buf> is assumed to be nul terminated and its
 length is determined by B<strlen>. The BIO is set to a read only state and
 as a result cannot be written to. This is useful when some data needs to be
 made available from a static area of memory in the form of a BIO. The

include/openssl/bio.h

@@ -655,7 +655,7 @@ long BIO_debug_callback(BIO *bio, int cmd, const char *argp, int argi,
 
 BIO_METHOD *BIO_s_mem(void);
 BIO_METHOD *BIO_s_secmem(void);
-BIO *BIO_new_mem_buf(void *buf, int len);
+BIO *BIO_new_mem_buf(const void *buf, int len);
 BIO_METHOD *BIO_s_socket(void);
 BIO_METHOD *BIO_s_connect(void);
 BIO_METHOD *BIO_s_accept(void);