Hello, > > I have here a self-written server program and the corresponding > > self-written client program. These run well together with libssl 1.1.0l, > > but with libssl 1.1.1d, the same programs give errors SSL_ERROR_SYSCALL > > in SSL_read(), no matter if I recompile the programs and then run them, > > or just replace libssl with the newer version. > > OpenSSL 1.1.1 supports TLS 1.3, which OpenSSL 1.1.0 did not. > > > So, I want to ask if there are any known incompabilities in the libssl > > versions that require me to change the code of the programs, or if there > > is > > any known bug in libssl1.1.1d that may cause the mentioned errors. > > Use of TLS 1.3 changes the communication patterns of the TLS protocol in > some non-trivial ways, and, if your application were fragile, it might > have gotten by with TLS 1.2, but the latent bugs could show up with TLS > 1.3. Now, I replaced TLS_server_method() and TLS_client_method() with TLSv1_2_server_method() and TLSv1_2_client_method() respectively, and the same error occurs. Regards Christoph
