Skip to contentSkip to conversation

ssl_openssl: fix compiler warning by removing getbio() wrapper

PATCH In review Steffan Karger 3 participants 5 messages Dec 14, 2017 – Jan 11, 2018

lore
Share & tools
lore
#0 lore raw

PATCH 1/1 ssl_openssl: fix compiler warning by removing getbio() wrapper

An API change in openssl 1.1 made the BIO_METHOD * returned by BIO_f_ssl() and BIO_s_mem() const, as well as the BIO_METHOD * argment of BIO_new() const. This meant that our getbio() function would either have an API inconsistent with 1.0 or 1.1.

The wrapper was basically an ASSERT, so fix this by replacing the wrapper with an ASSERT.

---
 src/openvpn/ssl_openssl.c | 23 +++--------------------
 1 file changed, 3 insertions(+), 20 deletions(-)
src/openvpn/ssl_openssl.c +3 -20
index 34c31b9..711bba1 100644
@@ -1416,23 +1416,6 @@ bio_debug_oc(const char *mode, BIO *bio)
 #endif /* ifdef BIO_DEBUG */
 
 /*
- * OpenVPN's interface to SSL/TLS authentication,
- * encryption, and decryption is exclusively
- * through "memory BIOs".
- */
-static BIO *
-getbio(BIO_METHOD *type, const char *desc)
-{
-    BIO *ret;
-    ret = BIO_new(type);
-    if (!ret)
-    {
-        crypto_msg(M_FATAL, "Error creating %s BIO", desc);
-    }
-    return ret;
-}
-
-/*
  * Write to an OpenSSL BIO in non-blocking mode.
  */
 static int
@@ -1573,9 +1556,9 @@ key_state_ssl_init(struct key_state_ssl *ks_ssl, const struct tls_root_ctx *ssl_
      * from verify callback*/
     SSL_set_ex_data(ks_ssl->ssl, mydata_index, session);
 
-    ks_ssl->ssl_bio = getbio(BIO_f_ssl(), "ssl_bio");
-    ks_ssl->ct_in = getbio(BIO_s_mem(), "ct_in");
-    ks_ssl->ct_out = getbio(BIO_s_mem(), "ct_out");
+    ASSERT((ks_ssl->ssl_bio = BIO_new(BIO_f_ssl())));
+    ASSERT((ks_ssl->ct_in = BIO_new(BIO_s_mem())));
+    ASSERT((ks_ssl->ct_out = BIO_new(BIO_s_mem())));
 
 #ifdef BIO_DEBUG
     bio_debug_oc("open ssl_bio", ks_ssl->ssl_bio);
Signature · 1 line
2.7.4
Acked-by on v1 1/1
#1 lore raw

Am 14.12.17 um 11:21 schrieb Steffan Karger:

Quoted 8 lines

An API change in openssl 1.1 made the BIO_METHOD * returned by BIO_f_ssl() and BIO_s_mem() const, as well as the BIO_METHOD * argment of BIO_new() const. This meant that our getbio() function would either have an API inconsistent with 1.0 or 1.1.

The wrapper was basically an ASSERT, so fix this by replacing the wrapper with an ASSERT.

Looks good. The wrapper does also not add much clarity or otherwise functionality.

Acked-by Arne Schwabe
#2 lore raw
In reply to Steffan Karger

Hi,

src/openvpn/ssl_openssl.c bio_debug_oc(const char *mode, BIO *bio) · line 1431

Quoted 4 lines · Steffan Karger
src/openvpn/ssl_openssl.c +0 -4
-    if (!ret)
-    {
-        crypto_msg(M_FATAL, "Error creating %s BIO", desc);
-    }

I'm not sure how likely these are going to fail, but the crypto_msg() had the benefit of actually telling us what the underlying library returned as error code...

If this won't ever happen except under very exceptional conditions, it won't matter much, though.

gert

Signature · 3 lines
now what should I write here...

Gert Doering - Munich, Germany                             [email protected]...
#3 lore raw

Hi,

Quoted 6 lines · Gert Doering

src/openvpn/ssl_openssl.c bio_debug_oc(const char *mode, BIO *bio) · line 1431

Quoted 4 lines · Steffan Karger
src/openvpn/ssl_openssl.c +0 -4
-    if (!ret)
-    {
-        crypto_msg(M_FATAL, "Error creating %s BIO", desc);
-    }
Quoted 6 lines

I'm not sure how likely these are going to fail, but the crypto_msg() had the benefit of actually telling us what the underlying library returned as error code...

If this won't ever happen except under very exceptional conditions, it won't matter much, though.

Fair point, but this is very unlikely to fail indeed. We use standard openssl-provided BIO_METHOD's, and do not do threading. The one error I could imagine is a malloc failure.

I still think it's fine to just go with the ASSERT().

-Steffan

#4 lore raw
In reply to Steffan Karger

Your patch has been applied to the master and release/2.4 branch.

commit 006d6a57b8835c15222359bfb42c95005723394c (master) commit 041b94c0ab1981c35f4294afc3f9e4f73ba9056c (release/2.4)

Author: Steffan Karger
Date:   Thu Dec 14 11:21:37 2017 +0100
     ssl_openssl: fix compiler warning by removing getbio() wrapper

     Signed-off-by: Steffan Karger <[email protected]...>
     Acked-by: Arne Schwabe <[email protected]...>
     Message-Id: <[email protected]...>
     URL: https://www.mail-archive.com/[email protected]/msg16083.html
     Signed-off-by: Gert Doering <[email protected]...>

--
kind regards,

Gert Doering