Port pbkdf2 specifics from fast_scram

.github/workflows/ci.yml

@@ -0,0 +1,28 @@
+name: ci
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+  workflow_dispatch:
+
+jobs:
+  test:
+    name: OTP ${{matrix.otp}}
+    strategy:
+      matrix:
+        otp: ['23.2', '22.3', '21.3']
+    runs-on: 'ubuntu-20.04'
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ErlGang/[email protected]
+        with:
+          otp-version: ${{ matrix.otp }}
+      - run: make rebar3
+      - run: make
+      - run: make test
+      - run: make dialyzer
+      - run: make codecov
+      - run: pip install --user codecov
+      - run: /home/runner/.local/bin/codecov

.gitignore

@@ -0,0 +1,30 @@
+.rebar3
+_*
+.eunit
+*.o
+*.d
+*.beam
+*.plt
+*.swp
+*.swo
+.erlang.cookie
+ebin
+log
+erl_crash.dump
+.rebar
+logs
+_build
+.idea
+*.iml
+rebar3.crashdump
+*~
+*.vim
+tags
+priv/
+/deps/
+/doc/
+/.fetch
+erl_crash.dump
+*.ez
+*.tar
+

LICENSE

@@ -0,0 +1,191 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   Copyright 2020, Nelson Vides <[email protected]>.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+

Makefile

@@ -0,0 +1,31 @@
+.PHONY: rel deps test
+
+all: deps compile
+
+compile: rebar3
+	./rebar3 compile
+
+deps: rebar3
+	./rebar3 get-deps
+
+clean: rebar3
+	./rebar3 clean
+
+test-deps: rebar3
+	./rebar3 get-deps
+
+test-compile: rebar3 test-deps
+	./rebar3 compile
+
+test: test-compile
+	./rebar3 as test ct
+
+codecov: _build/test/cover/ct.coverdata
+	./rebar3 as test codecov analyze
+
+rebar3:
+	wget https://github.com/erlang/rebar3/releases/download/3.13.2/rebar3 &&\
+	chmod u+x rebar3
+
+dialyzer: rebar3
+	./rebar3 dialyzer

README.md

@@ -0,0 +1,57 @@
+# Fast PBKDF2
+
+[![Actions Status](https://github.com/esl/fast_pbkdf2/workflows/ci/badge.svg)](https://github.com/esl/fast_pbkdf2/actions)
+[![codecov](https://codecov.io/gh/esl/fast_pbkdf2/branch/main/graph/badge.svg)](https://codecov.io/gh/esl/fast_pbkdf2)
+[![Hex](http://img.shields.io/hexpm/v/fast_pbkdf2.svg)](https://hex.pm/packages/fast_pbkdf2)
+
+`fast_pbkdf2` is an Erlang implementation of the [PBKDF2][PBKDF2], where the algorithm is a carefully-optimised NIF that uses timeslicing and nif scheduling to respect the latency properties of the BEAM.
+
+## Building
+`fast_pbkdf2` is a rebar3-compatible OTP application, that uses the [port_compiler](https://github.com/blt/port_compiler) for the C part of the code.
+
+Building is as easy as `rebar3 compile`, and using it in your projects as
+```erlang
+{deps,
+ [{fast_pbkdf2, "1.0.0"}]}.
+{plugins, [pc, rebar3_hex]}.
+{provider_hooks,
+ [{pre,
+   [{compile, {pc, compile}},
+    {clean, {pc, clean}}]}]}.
+```
+
+## Using
+
+```erlang
+DerivedPassword = fast_pbkdf2:pbkdf2(Hash, Password, Salt, IterationCount)
+```
+where `Hash` is the underlying hash function chosen as described by
+```erlang
+-type sha_type() :: crypto:sha1() | crypto:sha2().
+```
+
+### Custom `dkLen`
+If what you desire is PBKDF2 with custom `dkLen`(I assume that if that is what you want, then you know your RFC), in a way that allows you to request longer derived keys, you may use `fast_pbkdf2:pbkdf2_block/5` with a given block index and do the indexing and chunking yourself, or use `fast_pbkdf2:pbkdf2/5` for the full algorithm. However, it doesn't really add much more entropy to the derived key to use outputs larger than the output of the underlying hash, so you might as well, use `pbkdf2` where dkLen is that of the hash's output, which is the same than `pbkdf2_block` with index `1`, which is simply the `pbkdf2/4` function.
+
+## Performance
+
+### The problem
+PBKDF2 is a challenge derivation method, that is, it forces the client to compute a challenge in order to derive the desired password. But when the server implementation is slower than that of an attacker, it makes the server vulnerable to DoS by hogging itself with computations. We could see that on the CI and load-testing pipelines of [MongooseIM][MIM] for example.
+
+### The solution
+Is partial. We don't expect to have the fastest implementation, as that would be purely C code on GPUs, so unfortunately an attacker will pretty much always have better chances there. _But_ we can make the computation cheap enough for us that other computations —like the load of a session establishment— will be more relevant than that of the challenge; and also that other defence mechanisms like IP blacklisting or traffic shaping, will fire in good time.
+
+### The outcome
+On average it's 10x faster on the machines I've tested it (you can compare using the provided module in `./benchmarks/bench.ex`), but while the erlang implementation consumes memory linearly to the iteration count (1M it count with 120 clients quickly allocated 7GB of RAM, and 1M is common for password managers for example), the NIF implementation does not allocate any more memory. Also, the NIFS spend all of their time in user level alone, while the erlang one jumps to system calls in around ~2% of the time (I'd guess due to some heavy allocation and garbage collection patterns).
+
+## Credit where credit is due
+The initial algorithm and optimisations were taken from Joseph Birr-Pixton's
+[fastpbkdf2](https://github.com/ctz/fastpbkdf2)'s repository.
+
+## Read more:
+* Password-Based Cryptography Specification (PBKDF2): [RFC8018](https://tools.ietf.org/html/rfc8018#section-5.2)
+* HMAC: [RFC2104]( https://tools.ietf.org/html/rfc2104)
+* SHAs and HMAC-SHA: [RFC6234](https://tools.ietf.org/html/rfc6234)
+
+[MIM]: https://github.com/esl/MongooseIM
+[PBKDF2]: https://tools.ietf.org/html/rfc8018#section-5.2

benchmarks/bench.ex

@@ -0,0 +1,36 @@
+defmodule PBKDF2.Benchmarks do
+  def pbkdf2_input itCount do
+    password = :base64.encode(:crypto.strong_rand_bytes(10))
+    salt = :base64.encode(:crypto.strong_rand_bytes(16))
+    {password, salt, itCount}
+  end
+
+  def pbkdf2 {password, salt, it_count} do
+    :fast_pbkdf2.pbkdf2(:sha256, password, salt, it_count)
+  end
+end
+
+{:ok, :erl_pbkdf2} = :compile.file('./test/erl_pbkdf2.erl')
+
+Benchee.run(
+  %{
+    "fast_pbkdf2" => fn {password, salt, it_count} ->
+        :fast_pbkdf2.pbkdf2(:sha256, password, salt, it_count)
+      end,
+    "erl_pbkdf2 " => fn {password, salt, it_count} ->
+        :erl_pbkdf2.pbkdf2_oneblock(:sha256, password, salt, it_count)
+      end
+  },
+  inputs: %{
+    "1. 8" => PBKDF2.Benchmarks.pbkdf2_input(8),
+    "2. 512" => PBKDF2.Benchmarks.pbkdf2_input(512),
+    "3. 4096" => PBKDF2.Benchmarks.pbkdf2_input(4096),
+    "4. 10000" => PBKDF2.Benchmarks.pbkdf2_input(10000),
+    "5. 160000" => PBKDF2.Benchmarks.pbkdf2_input(160000),
+    "6. 500000" => PBKDF2.Benchmarks.pbkdf2_input(500000)
+  },
+  parallel: 12,
+  time: 5,
+  memory_time: 5
+)
+