Node.js has so far only supported user-defined DHE parameters and even
recommended generating custom parameters. This change lets users set the
dhparam option to 'auto' instead, in which case DHE parameters of
sufficient strength are selected automatically (from a small set of
well-known parameters). This has been recommended by OpenSSL for quite a
while, and it makes it much easier for Node.js TLS servers to properly
support DHE-based perfect forward secrecy.
This also updates the documentation to prioritize ECDHE over DHE, mostly
because the former tends to be more efficient and is enabled by default.
PR-URL: https://github.com/nodejs/node/pull/46978
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
In the manual page, there is a statement that ciphersuites contain
explicit default settings - all TLS 1.3 ciphersuites enabled.
In node, we assume that an empty setting mean no ciphersuites and
we disable TLS 1.3. A correct approach to disabling TLS 1.3 is to
disable TLS 1.3 and by not override the default ciphersuits
with an empty string.
So, only override OpenSSL's TLS 1.3 ciphersuites with an explicit
list of ciphers. If none are acceptable, the correct approach is
to disable TLS 1.3 instead elsewhere.
Fixes: https://github.com/nodejs/node/issues/43419
PR-URL: https://github.com/nodejs/node/pull/43427
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: James M Snell <jasnell@gmail.com>
Kumar Rishav