git: cb7cc72c546e - main - serf: Fix the default return value of the BIO control method.

[John Baldwin]

The branch main has been updated by jhb:

URL: https://cgit.FreeBSD.org/src/commit/?id=cb7cc72c546e0f87598961c3860e17391f42866c

commit cb7cc72c546e0f87598961c3860e17391f42866c
Author:     John Baldwin <jhb at FreeBSD.org>
AuthorDate: 2021-02-03 22:59:32 +0000
Commit:     John Baldwin <jhb at FreeBSD.org>
CommitDate: 2021-02-03 22:59:32 +0000

    serf: Fix the default return value of the BIO control method.
    
    OpenSSL BIO classes provide an abstraction for dealing with I/O.
    OpenSSL provides BIO classes for commonly used I/O primitives backed
    by file descriptors, sockets, etc. as well as permitting consumers
    of OpenSSL to define custom BIO classes.
    
    One of the methods BIO classes implement is a control method invoked
    by BIO_ctrl() for various ancilliary tasks somewhat analgous to
    fcntl() and ioctl() on file descriptors.  According to the BIO_ctrl(3)
    manual page, control methods should return 0 for unknown control
    requests.
    
    KTLS support in OpenSSL adds new control requests.  Two of those new
    requests are queries to determine if KTLS is enabled for either
    reading or writing.  These control reuquest return 1 if KTLS is
    enabled and 0 if it is not.
    
    serf includes two custom BIO classes for wrapping I/O requests from
    files and from a buffer in memory.  These BIO classes both use a
    custom control method.  However, this custom control method was
    returning 1 for unknown or unsupported control requests instead of 0.
    As a result, OpenSSL with KTLS believed that these BIOs were using
    KTLS and were thus adding headers and doing encryption/decryption in
    the BIO.  Correcting the return value removes this confusion.
    
    PR:             253135
    Reported by:    Guido Falsi <mad at madpilot.net>
    Reviewed by:    emaste
    MFC after:      3 days
    Sponsored by:   Netflix
    Differential Revision:  https://reviews.freebsd.org/D28472
---
 contrib/serf/buckets/ssl_buckets.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/contrib/serf/buckets/ssl_buckets.c b/contrib/serf/buckets/ssl_buckets.c
index b01e5359db08..3c8b7e2a685f 100644
--- a/contrib/serf/buckets/ssl_buckets.c
+++ b/contrib/serf/buckets/ssl_buckets.c
@@ -407,7 +407,7 @@ static int bio_bucket_destroy(BIO *bio)
 
 static long bio_bucket_ctrl(BIO *bio, int cmd, long num, void *ptr)
 {
-    long ret = 1;
+    long ret = 0;
 
     switch (cmd) {
     default:
@@ -415,6 +415,7 @@ static long bio_bucket_ctrl(BIO *bio, int cmd, long num, void *ptr)
         break;
     case BIO_CTRL_FLUSH:
         /* At this point we can't force a flush. */
+        ret = 1;
         break;
     case BIO_CTRL_PUSH:
     case BIO_CTRL_POP: