[FFmpeg-devel] [PATCH 02/14] avformat/tls_openssl: force dtls handshake to be blocking

[Timo Rothenpieler]

There is no sensible way to handle this otherwise anyway, one just has
to loop over this function until it succeeds.
---
 libavformat/tls_openssl.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/libavformat/tls_openssl.c b/libavformat/tls_openssl.c
index f6826222f9..54213c4090 100644
--- a/libavformat/tls_openssl.c
+++ b/libavformat/tls_openssl.c
@@ -685,27 +685,33 @@ static int openssl_dtls_verify_callback(int preverify_ok, X509_STORE_CTX *ctx)
 
 static int dtls_handshake(URLContext *h)
 {
-    int ret = 0, r0, r1;
+    int ret = 1, r0, r1;
     TLSContext *p = h->priv_data;
 
+    int was_nonblock = h->flags & AVIO_FLAG_NONBLOCK;
+    h->flags &= ~AVIO_FLAG_NONBLOCK;
+
     r0 = SSL_do_handshake(p->ssl);
-    r1 = SSL_get_error(p->ssl, r0);
     if (r0 <= 0) {
+        r1 = SSL_get_error(p->ssl, r0);
+
         if (r1 != SSL_ERROR_WANT_READ && r1 != SSL_ERROR_WANT_WRITE && r1 != SSL_ERROR_ZERO_RETURN) {
-            av_log(p, AV_LOG_ERROR, "TLS: Read failed, r0=%d, r1=%d %s\n", r0, r1, openssl_get_error(p));
-            ret = AVERROR(EIO);
+            av_log(p, AV_LOG_ERROR, "Handshake failed, r0=%d, r1=%d\n", r0, r1);
+            ret = print_ssl_error(h, r0);
             goto end;
         }
     } else {
-        av_log(p, AV_LOG_TRACE, "TLS: Read %d bytes, r0=%d, r1=%d\n", r0, r0, r1);
+        av_log(p, AV_LOG_TRACE, "Handshake success, r0=%d\n", r0);
     }
 
-    /* Check whether the DTLS is completed. */
     if (SSL_is_init_finished(p->ssl) != 1)
         goto end;
 
+    ret = 0;
     p->tls_shared.state = DTLS_STATE_FINISHED;
 end:
+    if (was_nonblock)
+        h->flags |= AVIO_FLAG_NONBLOCK;
     return ret;
 }
 
-- 
2.49.0