Revert "Preserve connection custom extensions in SSL_set_SSL_CTX()" This reverts commit 403ba31a02e47d37070036529966d5a94d98c6fd. PR #27706 (that this PR reverts) was intended to fix nginx/nginx#711 The problem was that when calling SSL_set_SSL_CTX() from an SNI callback when using a QUIC object, the QUIC custom extensions were not being handled correctly. The fix attempted to resolve this to make sure that they were correctly being copied. However, in reality there was a bug in the SNI callback code that meant when we called it from a QUIC connection we were passing the *inner* TLS object instead of the real QUIC one. The *inner* TLS object should be entirely internal and not exposed to user callbacks. This bug was fixed in dc84829cc5. Once the above fix was in place `SSL_set_SSL_CTX()` immediately fails when called with a QUIC object via the SNI callback. This was always the intended behaviour - its use with a QUIC object was blocked since the very beginning - but the fact that we passed the inner TLS object by mistake circumvented the check when it was invoked from the SNI callback. The fix in dc84829cc5 actually landed *before* the commit that this PR reverts. So, in reality the nginx bug was already "fixed" by the time that PR #27706 was merged (fixed in the sense that the invocation of `SSL_set_SSL_CTX()` fails gracefully). The code that it introduced can not be reached (and never could be) because calling `SSL_set_SSL_CTX()` is explicitly blocked when using a QUIC object. Therefore we should remove this dead code. Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Tim Hudson <tjh@openssl.org> Reviewed-by: Saša Nedvědický <sashan@openssl.org> Reviewed-by: Tomas Mraz <tomas@openssl.foundation> MergeDate: Wed May 13 16:23:24 2026 (Merged from https://github.com/openssl/openssl/pull/31159)
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