Bug #13603: SecureRandom.uuid is not valid v4 and/or RFC 4122

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-darwin16]
• Backport: 2.2: UNKNOWN, 2.3: UNKNOWN, 2.4: UNKNOWN

[kulikov-im (Evgeniy Kulikov)]

https://www.ietf.org/rfc/rfc4122.txt (#4.4)

(reopen from https://bugs.ruby-lang.org/issues/10093#change-65105)

current test is https://github.com/ruby/ruby/blob/ruby_2_4/test/test_securerandom.rb#L174

def test_uuid
  uuid = @it.uuid
  assert_equal(36, uuid.size)
  assert_match(/\A\h{8}-\h{4}-\h{4}-\h{4}-\h{12}\z/, uuid)
end

thats not valid

Here Golang example of test-case - https://github.com/satori/go.uuid/blob/master/uuid_test.go#L589

must check:

• UUID Version

uuid.bytes[6] >> 4 == 4

• RFC4122

(uuid.bytes[8] & 0xc0) | 0x80 == 0x80

valid test-case is:

def test_uuid
  uuid = @it.uuid

  assert_equal(36, uuid.size)

  # Check UUID Version:
  assert_equal(uuid.bytes[6] >> 4, 4)

  # Check RFC4122
  assert_equal((uuid[8] & 0xc0) | 0x80, 0x80)

  assert_match(/\A\h{8}-\h{4}-\h{4}-\h{4}-\h{12}\z/, uuid)
end

This problem has to be from ruby version 1.9.3 to 2.4.1 (current)

[shyouhei (Shyouhei Urabe)]

Is this a matter of our test code, or the actual output of SecureRandom.uuid does not conform the RFC?

[kulikov-im (Evgeniy Kulikov)]

shyouhei (Shyouhei Urabe) wrote:

Is this a matter of our test code, or the actual output of SecureRandom.uuid does not conform the RFC?

test-case from repo (https://github.com/ruby/ruby/blob/ruby_2_4/test/test_securerandom.rb#L174) doesn't check version and specification

i have mistake in my issue (code above), whats need:

• uuid - is string, must be converted to uuid_bytes, example - get UUID bytes from string (https://github.com/satori/go.uuid/blob/master/uuid.go#L366)
• must get and check UUID version (https://github.com/satori/go.uuid/blob/master/uuid.go#L173)
• must get and check UUID variant (https://github.com/satori/go.uuid/blob/master/uuid.go#L178)

Later, I can write example

---

Now i have some problems with hex-decode in ruby

• Status changed from Open to Closed

Applied in changeset git|5fef46ae0dedaab359f55bc3680f4278eb7da98d.

---

Test SecureRandom.uuid format

SecureRandom uses v4 UUIDs, which are completely random except for
6 bits, 4 in the version field and 2 in the clk_seq_hi_res field.
Add a test that those bit patterns are set correctly for v4 UUIDs,
per RFC 4122 section 4.4.

Fixes [Bug #13603]