[erlang-questions] SSL and hardcoded DH prime

[Alexander Petrovsky]

Hello!

We have stumble upon default DH prime (2048 bits) in Erlang when we try to
establish TLS session with cisco spa303 (VoIP hardphone)
via TLS_DHE_RSA_WITH_AES_256_CBC_SHA (0x0039) cipher suite. Unfortunately,
this hardphone can work only with 1024 bit DH prime.

I wonder, why Ingela hardcoded this DH prime -
https://github.com/erlang/otp/commit/3458af579af6600870c5ada69b81085f47e9f52b

In my synthetical tests, new DH prime generation is fast enough
(crypto:strong_rand_bytes(256)), about 17 us in 99 percentile in 1000000
iterations.

Why Ingela has hardcoded this DH prime and is any reason why I shouldn't
generate DH prime in real-time?

-- 
Петровский Александр / Alexander Petrovsky,

Skype: askjuise
Phone: +7 931 9877991
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