Add OpenSSL TLS 1.3 early data (0-RTT) support#22802
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This looks good to me (but I have limited knowledge of openssl, so this needs another review).
This builds on the session resumption support to let clients send and servers accept TLS 1.3 early data through the stream SSL context. Clients set the early_data context option (a string) to send 0-RTT data, which is only sent when the resumed session allows it. Servers enable acceptance with max_early_data and receive the data through the early_data_cb callback, so nothing is buffered on the stream. The outcome is reported as 'accepted', 'rejected' or 'not_sent' in the early_data key of the crypto stream_get_meta_data() array. Enabling early data also shares the server SSL_CTX across accepted connections and keeps the session cache on, both of which 0-RTT resumption requires.
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I think you have good enough knowledge. :) There is certainly no one who does not have limited knowledge so it would never get reviewed so better to just merge it. It's a simple addition that just follows structure what was added in session and psk support. |
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This builds on the session resumption support to let clients send and servers accept TLS 1.3 early data through the stream SSL context.
Clients set the early_data context option (a string) to send 0-RTT data, which is only sent when the resumed session allows it. Servers enable acceptance with
max_early_dataand receive the data through theearly_data_cbcallback, so nothing is buffered on the stream. The outcome is reported asaccepted,rejectedornot_sentin the early_data key of the crypto stream_get_meta_data() array.Enabling early data also shares the server SSL_CTX across accepted connections and keeps the session cache on, both of which 0-RTT resumption requires.