While the traditional OpenSSL return value and behaviour of BIO_dump(3)

is pure comedy gold, and now documented as such, sadly this bit of pure
Muppet genius can't really in good consience stay in the tree as is.

Change BIO_dump to always return the number of bytes printed on success
and to stop printing and return -1 on failure if a writing function
fails.

ok tb@, jsing@

1 files changed, 10 insertions, 5 deletions

diff --git a/src/lib/libcrypto/bio/b_dump.c b/src/lib/libcrypto/bio/b_dump.c
index 0214addc8b..7e1c2d7947 100644
--- a/src/lib/libcrypto/bio/b_dump.c
+++ b/src/lib/libcrypto/bio/b_dump.c
@@ -1,10 +1,10 @@
-/* $OpenBSD: b_dump.c,v 1.21 2015/04/23 06:11:19 deraadt Exp $ */
+/* $OpenBSD: b_dump.c,v 1.22 2021/07/11 20:18:07 beck Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
  * This package is an SSL implementation written
  * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
+* The implementation was written so as to conform with Netscapes SSL.
  *
  * This library is free for commercial and non-commercial use as long as
  * the following conditions are aheared to.  The following conditions
@@ -82,7 +82,7 @@ BIO_dump_indent_cb(int (*cb)(const void *data, size_t len, void *u),
 {
         int ret = 0;
         char buf[288 + 1], tmp[20], str[128 + 1];
-        int i, j, rows, trc;
+        int i, j, rows, trc, written;
         unsigned char ch;
         int dump_width;
 
@@ -133,13 +133,18 @@ BIO_dump_indent_cb(int (*cb)(const void *data, size_t len, void *u),
                 /* if this is the last call then update the ddt_dump thing so
                  * that we will move the selection point in the debug window
                  */
-                ret += cb((void *)buf, strlen(buf), u);
+                if ((written = cb((void *)buf, strlen(buf), u)) < 0)
+                        return -1;
+                ret += written;
+
         }
 #ifdef TRUNCATE
         if (trc > 0) {
                 snprintf(buf, sizeof buf, "%s%04x - <SPACES/NULS>\n",
                     str, len + trc);
-                ret += cb((void *)buf, strlen(buf), u);
+                if ((written = cb((void *)buf, strlen(buf), u)) < 0)
+                        return -1;
+                ret += written;
         }
 #endif
         return (ret);