1crypto(7) Erlang Application Definition crypto(7)
2
6 crypto - The Crypto Application
7
9 The purpose of the Crypto application is to provide an Erlang API to
10 cryptographic functions, see crypto(3). Note that the API is on a
11 fairly low level and there are some corresponding API functions avail‐
12 able in public_key(3), on a higher abstraction level, that uses the
13 crypto application in its implementation.
14
16 The current crypto implementation uses nifs to interface OpenSSLs
17 crypto library and may work with limited functionality with as old ver‐
18 sions as OpenSSL 0.9.8c. FIPS mode support requires at least version
19 1.0.1 and a FIPS capable OpenSSL installation. We recommend using a
20 version that is officially supported by the OpenSSL project. API com‐
21 patible backends like LibreSSL should also work.
22 The crypto app is tested daily with at least one version of each of the
24 OpenSSL 1.0.1, 1.0.2, 1.1.0, 1.1.1 and 3.0. FIPS mode is also tested
25 for 1.0.1, 1.0.2 and 3.0.
26 Using OpenSSL 3.0 with Engines is not yet supported by the OTP/crypto
28 app.
29 Source releases of OpenSSL can be downloaded from the OpenSSL project
31 home page, or mirror sites listed there.
32
34 The following configuration parameters are defined for the crypto ap‐
35 plication. See app(3) for more information about configuration parame‐
36 ters.
37 fips_mode = boolean():
39 Specifies whether to run crypto in FIPS mode. This setting will
40 take effect when the nif module is loaded. If FIPS mode is re‐
41 quested but not available at run time the nif module and thus the
42 crypto module will fail to load. This mechanism prevents the acci‐
43 dental use of non-validated algorithms.
44 rand_cache_size = integer():
46 Sets the cache size in bytes to use by
47 crypto:rand_seed_alg(crypto_cache) and
48 crypto:rand_seed_alg_s(crypto_cache). This parameter is read when a
49 seed function is called, and then kept in generators state object.
50 It has a rather small default value that causes reads of strong
51 random bytes about once per hundred calls for a random value. The
52 set value is rounded up to an integral number of words of the size
53 these seed functions use.
54
56 application(3)
57Ericsson AB crypto 5.3 crypto(7)