gistfile1.txt

erl                                                                     
Erlang R16B01 (erts-5.10.2) [source-bdf5300] [64-bit] [smp:4:4] [async-threads:10] [hipe] [kernel-poll:false]

Eshell V5.10.2  (abort with ^G)
1> crypto:start().
ok
2> H = crypto:hmac_init(sha, "test").
<<128,144,53,134,175,127,0,0,128,144,53,134,175,127,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,...>>
3> H2 = crypto:hmac_update(H, "hello world").
<<128,144,53,134,175,127,0,0,128,144,53,134,175,127,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,...>>
4> crypto:hmac_final(H2) == crypto:hmac_final(H).
[1]    20604 segmentation fault (core dumped)  erl
                                                  %     

Is this something you want to do? That is, use the same hmac context several times (H in this case)? Or is it just something you discovered from a typo in your code?

Fix done for OTP 17.0.
You will get a badarg exception instead of segmentation fault.
We can not support hmac context reuse as OpenSSL does not support it.

/Sverker, Erlang/OTP