1 // Copyright 2016 Google Inc. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
13 // Well known namespace IDs and UUIDs
15 NameSpaceDNS = Must(Parse("6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
16 NameSpaceURL = Must(Parse("6ba7b811-9dad-11d1-80b4-00c04fd430c8"))
17 NameSpaceOID = Must(Parse("6ba7b812-9dad-11d1-80b4-00c04fd430c8"))
18 NameSpaceX500 = Must(Parse("6ba7b814-9dad-11d1-80b4-00c04fd430c8"))
19 Nil UUID // empty UUID, all zeros
22 // NewHash returns a new UUID derived from the hash of space concatenated with
23 // data generated by h. The hash should be at least 16 byte in length. The
24 // first 16 bytes of the hash are used to form the UUID. The version of the
25 // UUID will be the lower 4 bits of version. NewHash is used to implement
26 // NewMD5 and NewSHA1.
27 func NewHash(h hash.Hash, space UUID, data []byte, version int) UUID {
34 uuid[6] = (uuid[6] & 0x0f) | uint8((version&0xf)<<4)
35 uuid[8] = (uuid[8] & 0x3f) | 0x80 // RFC 4122 variant
39 // NewMD5 returns a new MD5 (Version 3) UUID based on the
40 // supplied name space and data. It is the same as calling:
42 // NewHash(md5.New(), space, data, 3)
43 func NewMD5(space UUID, data []byte) UUID {
44 return NewHash(md5.New(), space, data, 3)
47 // NewSHA1 returns a new SHA1 (Version 5) UUID based on the
48 // supplied name space and data. It is the same as calling:
50 // NewHash(sha1.New(), space, data, 5)
51 func NewSHA1(space UUID, data []byte) UUID {
52 return NewHash(sha1.New(), space, data, 5)