pax_global_header00006660000000000000000000000064136571213300014513gustar00rootroot0000000000000052 comment=ea51bea511f75cfa3ef6098cc253c5c3609b037a go-digest-1.0.0/000077500000000000000000000000001365712133000133735ustar00rootroot00000000000000go-digest-1.0.0/.mailmap000066400000000000000000000003441365712133000150150ustar00rootroot00000000000000Aaron Lehmann Derek McGowan Stephen J Day Haibing Zhou go-digest-1.0.0/.pullapprove.yml000066400000000000000000000006741365712133000165540ustar00rootroot00000000000000version: 2 requirements: signed_off_by: required: true always_pending: title_regex: '^WIP' explanation: 'Work in progress...' group_defaults: required: 2 approve_by_comment: enabled: true approve_regex: '^LGTM' reject_regex: '^Rejected' reset_on_push: enabled: true author_approval: ignored: true conditions: branches: - master groups: go-digest: teams: - go-digest-maintainers go-digest-1.0.0/.travis.yml000066400000000000000000000000621365712133000155020ustar00rootroot00000000000000language: go go: - 1.12.x - 1.13.x - master go-digest-1.0.0/CONTRIBUTING.md000066400000000000000000000056371365712133000156370ustar00rootroot00000000000000# Contributing to Docker open source projects Want to hack on this project? Awesome! Here are instructions to get you started. This project is a part of the [Docker](https://www.docker.com) project, and follows the same rules and principles. If you're already familiar with the way Docker does things, you'll feel right at home. Otherwise, go read Docker's [contributions guidelines](https://github.com/docker/docker/blob/master/CONTRIBUTING.md), [issue triaging](https://github.com/docker/docker/blob/master/project/ISSUE-TRIAGE.md), [review process](https://github.com/docker/docker/blob/master/project/REVIEWING.md) and [branches and tags](https://github.com/docker/docker/blob/master/project/BRANCHES-AND-TAGS.md). For an in-depth description of our contribution process, visit the contributors guide: [Understand how to contribute](https://docs.docker.com/opensource/workflow/make-a-contribution/) ### Sign your work The sign-off is a simple line at the end of the explanation for the patch. Your signature certifies that you wrote the patch or otherwise have the right to pass it on as an open-source patch. The rules are pretty simple: if you can certify the below (from [developercertificate.org](http://developercertificate.org/)): ``` Developer Certificate of Origin Version 1.1 Copyright (C) 2004, 2006 The Linux Foundation and its contributors. 1 Letterman Drive Suite D4700 San Francisco, CA, 94129 Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Developer's Certificate of Origin 1.1 By making a contribution to this project, I certify that: (a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or (b) The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or (c) The contribution was provided directly to me by some other person who certified (a), (b) or (c) and I have not modified it. (d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved. ``` Then you just add a line to every git commit message: Signed-off-by: Joe Smith Use your real name (sorry, no pseudonyms or anonymous contributions.) If you set your `user.name` and `user.email` git configs, you can sign your commit automatically with `git commit -s`. go-digest-1.0.0/LICENSE000066400000000000000000000250611365712133000144040ustar00rootroot00000000000000 Apache License Version 2.0, January 2004 https://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. 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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. 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Creative Commons may be contacted at creativecommons.org. go-digest-1.0.0/MAINTAINERS000066400000000000000000000003751365712133000150750ustar00rootroot00000000000000Derek McGowan (@dmcgowan) Stephen Day (@stevvooe) Vincent Batts (@vbatts) Akihiro Suda (@AkihiroSuda) Sebastiaan van Stijn (@thaJeztah) go-digest-1.0.0/README.md000066400000000000000000000102051365712133000146500ustar00rootroot00000000000000# go-digest [![GoDoc](https://godoc.org/github.com/opencontainers/go-digest?status.svg)](https://godoc.org/github.com/opencontainers/go-digest) [![Go Report Card](https://goreportcard.com/badge/github.com/opencontainers/go-digest)](https://goreportcard.com/report/github.com/opencontainers/go-digest) [![Build Status](https://travis-ci.org/opencontainers/go-digest.svg?branch=master)](https://travis-ci.org/opencontainers/go-digest) Common digest package used across the container ecosystem. Please see the [godoc](https://godoc.org/github.com/opencontainers/go-digest) for more information. # What is a digest? A digest is just a [hash](https://en.wikipedia.org/wiki/Hash_function). The most common use case for a digest is to create a content identifier for use in [Content Addressable Storage](https://en.wikipedia.org/wiki/Content-addressable_storage) systems: ```go id := digest.FromBytes([]byte("my content")) ``` In the example above, the id can be used to uniquely identify the byte slice "my content". This allows two disparate applications to agree on a verifiable identifier without having to trust one another. An identifying digest can be verified, as follows: ```go if id != digest.FromBytes([]byte("my content")) { return errors.New("the content has changed!") } ``` A `Verifier` type can be used to handle cases where an `io.Reader` makes more sense: ```go rd := getContent() verifier := id.Verifier() io.Copy(verifier, rd) if !verifier.Verified() { return errors.New("the content has changed!") } ``` Using [Merkle DAGs](https://en.wikipedia.org/wiki/Merkle_tree), this can power a rich, safe, content distribution system. # Usage While the [godoc](https://godoc.org/github.com/opencontainers/go-digest) is considered the best resource, a few important items need to be called out when using this package. 1. Make sure to import the hash implementations into your application or the package will panic. You should have something like the following in the main (or other entrypoint) of your application: ```go import ( _ "crypto/sha256" _ "crypto/sha512" ) ``` This may seem inconvenient but it allows you replace the hash implementations with others, such as https://github.com/stevvooe/resumable. 2. Even though `digest.Digest` may be assemblable as a string, _always_ verify your input with `digest.Parse` or use `Digest.Validate` when accepting untrusted input. While there are measures to avoid common problems, this will ensure you have valid digests in the rest of your application. 3. While alternative encodings of hash values (digests) are possible (for example, base64), this package deals exclusively with hex-encoded digests. # Stability The Go API, at this stage, is considered stable, unless otherwise noted. As always, before using a package export, read the [godoc](https://godoc.org/github.com/opencontainers/go-digest). # Contributing This package is considered fairly complete. It has been in production in thousands (millions?) of deployments and is fairly battle-hardened. New additions will be met with skepticism. If you think there is a missing feature, please file a bug clearly describing the problem and the alternatives you tried before submitting a PR. ## Code of Conduct Participation in the OpenContainers community is governed by [OpenContainer's Code of Conduct][code-of-conduct]. ## Security If you find an issue, please follow the [security][security] protocol to report it. # Copyright and license Copyright © 2019, 2020 OCI Contributors Copyright © 2016 Docker, Inc. All rights reserved, except as follows. Code is released under the [Apache 2.0 license](LICENSE). This `README.md` file and the [`CONTRIBUTING.md`](CONTRIBUTING.md) file are licensed under the Creative Commons Attribution 4.0 International License under the terms and conditions set forth in the file [`LICENSE.docs`](LICENSE.docs). You may obtain a duplicate copy of the same license, titled CC BY-SA 4.0, at http://creativecommons.org/licenses/by-sa/4.0/. [security]: https://github.com/opencontainers/org/blob/master/security [code-of-conduct]: https://github.com/opencontainers/org/blob/master/CODE_OF_CONDUCT.md go-digest-1.0.0/algorithm.go000066400000000000000000000133701365712133000157140ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "crypto" "fmt" "hash" "io" "regexp" ) // Algorithm identifies and implementation of a digester by an identifier. // Note the that this defines both the hash algorithm used and the string // encoding. type Algorithm string // supported digest types const ( SHA256 Algorithm = "sha256" // sha256 with hex encoding (lower case only) SHA384 Algorithm = "sha384" // sha384 with hex encoding (lower case only) SHA512 Algorithm = "sha512" // sha512 with hex encoding (lower case only) // Canonical is the primary digest algorithm used with the distribution // project. Other digests may be used but this one is the primary storage // digest. Canonical = SHA256 ) var ( // TODO(stevvooe): Follow the pattern of the standard crypto package for // registration of digests. Effectively, we are a registerable set and // common symbol access. // algorithms maps values to hash.Hash implementations. Other algorithms // may be available but they cannot be calculated by the digest package. algorithms = map[Algorithm]crypto.Hash{ SHA256: crypto.SHA256, SHA384: crypto.SHA384, SHA512: crypto.SHA512, } // anchoredEncodedRegexps contains anchored regular expressions for hex-encoded digests. // Note that /A-F/ disallowed. anchoredEncodedRegexps = map[Algorithm]*regexp.Regexp{ SHA256: regexp.MustCompile(`^[a-f0-9]{64}$`), SHA384: regexp.MustCompile(`^[a-f0-9]{96}$`), SHA512: regexp.MustCompile(`^[a-f0-9]{128}$`), } ) // Available returns true if the digest type is available for use. If this // returns false, Digester and Hash will return nil. func (a Algorithm) Available() bool { h, ok := algorithms[a] if !ok { return false } // check availability of the hash, as well return h.Available() } func (a Algorithm) String() string { return string(a) } // Size returns number of bytes returned by the hash. func (a Algorithm) Size() int { h, ok := algorithms[a] if !ok { return 0 } return h.Size() } // Set implemented to allow use of Algorithm as a command line flag. func (a *Algorithm) Set(value string) error { if value == "" { *a = Canonical } else { // just do a type conversion, support is queried with Available. *a = Algorithm(value) } if !a.Available() { return ErrDigestUnsupported } return nil } // Digester returns a new digester for the specified algorithm. If the algorithm // does not have a digester implementation, nil will be returned. This can be // checked by calling Available before calling Digester. func (a Algorithm) Digester() Digester { return &digester{ alg: a, hash: a.Hash(), } } // Hash returns a new hash as used by the algorithm. If not available, the // method will panic. Check Algorithm.Available() before calling. func (a Algorithm) Hash() hash.Hash { if !a.Available() { // Empty algorithm string is invalid if a == "" { panic(fmt.Sprintf("empty digest algorithm, validate before calling Algorithm.Hash()")) } // NOTE(stevvooe): A missing hash is usually a programming error that // must be resolved at compile time. We don't import in the digest // package to allow users to choose their hash implementation (such as // when using stevvooe/resumable or a hardware accelerated package). // // Applications that may want to resolve the hash at runtime should // call Algorithm.Available before call Algorithm.Hash(). panic(fmt.Sprintf("%v not available (make sure it is imported)", a)) } return algorithms[a].New() } // Encode encodes the raw bytes of a digest, typically from a hash.Hash, into // the encoded portion of the digest. func (a Algorithm) Encode(d []byte) string { // TODO(stevvooe): Currently, all algorithms use a hex encoding. When we // add support for back registration, we can modify this accordingly. return fmt.Sprintf("%x", d) } // FromReader returns the digest of the reader using the algorithm. func (a Algorithm) FromReader(rd io.Reader) (Digest, error) { digester := a.Digester() if _, err := io.Copy(digester.Hash(), rd); err != nil { return "", err } return digester.Digest(), nil } // FromBytes digests the input and returns a Digest. func (a Algorithm) FromBytes(p []byte) Digest { digester := a.Digester() if _, err := digester.Hash().Write(p); err != nil { // Writes to a Hash should never fail. None of the existing // hash implementations in the stdlib or hashes vendored // here can return errors from Write. Having a panic in this // condition instead of having FromBytes return an error value // avoids unnecessary error handling paths in all callers. panic("write to hash function returned error: " + err.Error()) } return digester.Digest() } // FromString digests the string input and returns a Digest. func (a Algorithm) FromString(s string) Digest { return a.FromBytes([]byte(s)) } // Validate validates the encoded portion string func (a Algorithm) Validate(encoded string) error { r, ok := anchoredEncodedRegexps[a] if !ok { return ErrDigestUnsupported } // Digests much always be hex-encoded, ensuring that their hex portion will // always be size*2 if a.Size()*2 != len(encoded) { return ErrDigestInvalidLength } if r.MatchString(encoded) { return nil } return ErrDigestInvalidFormat } go-digest-1.0.0/algorithm_test.go000066400000000000000000000051401365712133000167470ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "bytes" "crypto/rand" _ "crypto/sha256" _ "crypto/sha512" "flag" "fmt" "strings" "testing" ) func TestFlagInterface(t *testing.T) { var ( alg Algorithm flagSet flag.FlagSet ) flagSet.Var(&alg, "algorithm", "set the digest algorithm") for _, testcase := range []struct { Name string Args []string Err error Expected Algorithm }{ { Name: "Invalid", Args: []string{"-algorithm", "bean"}, Err: ErrDigestUnsupported, }, { Name: "Default", Args: []string{"unrelated"}, Expected: "sha256", }, { Name: "Other", Args: []string{"-algorithm", "sha512"}, Expected: "sha512", }, } { t.Run(testcase.Name, func(t *testing.T) { alg = Canonical if err := flagSet.Parse(testcase.Args); err != testcase.Err { if testcase.Err == nil { t.Fatal("unexpected error", err) } // check that flag package returns correct error if !strings.Contains(err.Error(), testcase.Err.Error()) { t.Fatalf("unexpected error: %v != %v", err, testcase.Err) } return } if alg != testcase.Expected { t.Fatalf("unexpected algorithm: %v != %v", alg, testcase.Expected) } }) } } func TestFroms(t *testing.T) { p := make([]byte, 1<<20) rand.Read(p) for alg := range algorithms { h := alg.Hash() h.Write(p) expected := Digest(fmt.Sprintf("%s:%x", alg, h.Sum(nil))) readerDgst, err := alg.FromReader(bytes.NewReader(p)) if err != nil { t.Fatalf("error calculating hash from reader: %v", err) } dgsts := []Digest{ alg.FromBytes(p), alg.FromString(string(p)), readerDgst, } if alg == Canonical { readerDgst, err := FromReader(bytes.NewReader(p)) if err != nil { t.Fatalf("error calculating hash from reader: %v", err) } dgsts = append(dgsts, FromBytes(p), FromString(string(p)), readerDgst) } for _, dgst := range dgsts { if dgst != expected { t.Fatalf("unexpected digest %v != %v", dgst, expected) } } } } go-digest-1.0.0/digest.go000066400000000000000000000114031365712133000152000ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "fmt" "hash" "io" "regexp" "strings" ) // Digest allows simple protection of hex formatted digest strings, prefixed // by their algorithm. Strings of type Digest have some guarantee of being in // the correct format and it provides quick access to the components of a // digest string. // // The following is an example of the contents of Digest types: // // sha256:7173b809ca12ec5dee4506cd86be934c4596dd234ee82c0662eac04a8c2c71dc // // This allows to abstract the digest behind this type and work only in those // terms. type Digest string // NewDigest returns a Digest from alg and a hash.Hash object. func NewDigest(alg Algorithm, h hash.Hash) Digest { return NewDigestFromBytes(alg, h.Sum(nil)) } // NewDigestFromBytes returns a new digest from the byte contents of p. // Typically, this can come from hash.Hash.Sum(...) or xxx.SumXXX(...) // functions. This is also useful for rebuilding digests from binary // serializations. func NewDigestFromBytes(alg Algorithm, p []byte) Digest { return NewDigestFromEncoded(alg, alg.Encode(p)) } // NewDigestFromHex is deprecated. Please use NewDigestFromEncoded. func NewDigestFromHex(alg, hex string) Digest { return NewDigestFromEncoded(Algorithm(alg), hex) } // NewDigestFromEncoded returns a Digest from alg and the encoded digest. func NewDigestFromEncoded(alg Algorithm, encoded string) Digest { return Digest(fmt.Sprintf("%s:%s", alg, encoded)) } // DigestRegexp matches valid digest types. var DigestRegexp = regexp.MustCompile(`[a-z0-9]+(?:[.+_-][a-z0-9]+)*:[a-zA-Z0-9=_-]+`) // DigestRegexpAnchored matches valid digest types, anchored to the start and end of the match. var DigestRegexpAnchored = regexp.MustCompile(`^` + DigestRegexp.String() + `$`) var ( // ErrDigestInvalidFormat returned when digest format invalid. ErrDigestInvalidFormat = fmt.Errorf("invalid checksum digest format") // ErrDigestInvalidLength returned when digest has invalid length. ErrDigestInvalidLength = fmt.Errorf("invalid checksum digest length") // ErrDigestUnsupported returned when the digest algorithm is unsupported. ErrDigestUnsupported = fmt.Errorf("unsupported digest algorithm") ) // Parse parses s and returns the validated digest object. An error will // be returned if the format is invalid. func Parse(s string) (Digest, error) { d := Digest(s) return d, d.Validate() } // FromReader consumes the content of rd until io.EOF, returning canonical digest. func FromReader(rd io.Reader) (Digest, error) { return Canonical.FromReader(rd) } // FromBytes digests the input and returns a Digest. func FromBytes(p []byte) Digest { return Canonical.FromBytes(p) } // FromString digests the input and returns a Digest. func FromString(s string) Digest { return Canonical.FromString(s) } // Validate checks that the contents of d is a valid digest, returning an // error if not. func (d Digest) Validate() error { s := string(d) i := strings.Index(s, ":") if i <= 0 || i+1 == len(s) { return ErrDigestInvalidFormat } algorithm, encoded := Algorithm(s[:i]), s[i+1:] if !algorithm.Available() { if !DigestRegexpAnchored.MatchString(s) { return ErrDigestInvalidFormat } return ErrDigestUnsupported } return algorithm.Validate(encoded) } // Algorithm returns the algorithm portion of the digest. This will panic if // the underlying digest is not in a valid format. func (d Digest) Algorithm() Algorithm { return Algorithm(d[:d.sepIndex()]) } // Verifier returns a writer object that can be used to verify a stream of // content against the digest. If the digest is invalid, the method will panic. func (d Digest) Verifier() Verifier { return hashVerifier{ hash: d.Algorithm().Hash(), digest: d, } } // Encoded returns the encoded portion of the digest. This will panic if the // underlying digest is not in a valid format. func (d Digest) Encoded() string { return string(d[d.sepIndex()+1:]) } // Hex is deprecated. Please use Digest.Encoded. func (d Digest) Hex() string { return d.Encoded() } func (d Digest) String() string { return string(d) } func (d Digest) sepIndex() int { i := strings.Index(string(d), ":") if i < 0 { panic(fmt.Sprintf("no ':' separator in digest %q", d)) } return i } go-digest-1.0.0/digest_test.go000066400000000000000000000102121365712133000162340ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "testing" ) func TestParseDigest(t *testing.T) { for _, testcase := range []struct { input string err error algorithm Algorithm encoded string }{ { input: "sha256:e58fcf7418d4390dec8e8fb69d88c06ec07039d651fedd3aa72af9972e7d046b", algorithm: "sha256", encoded: "e58fcf7418d4390dec8e8fb69d88c06ec07039d651fedd3aa72af9972e7d046b", }, { input: "sha384:d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", algorithm: "sha384", encoded: "d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", }, { // empty hex input: "sha256:", err: ErrDigestInvalidFormat, }, { // empty hex input: ":", err: ErrDigestInvalidFormat, }, { // just hex input: "d41d8cd98f00b204e9800998ecf8427e", err: ErrDigestInvalidFormat, }, { // not hex input: "sha256:d41d8cd98f00b204e9800m98ecf8427e", err: ErrDigestInvalidLength, }, { // too short input: "sha256:abcdef0123456789", err: ErrDigestInvalidLength, }, { // too short (from different algorithm) input: "sha512:abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789", err: ErrDigestInvalidLength, }, { input: "foo:d41d8cd98f00b204e9800998ecf8427e", err: ErrDigestUnsupported, }, { // repeated separators input: "sha384__foo+bar:d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", err: ErrDigestInvalidFormat, }, { // ensure that we parse, but we don't have support for the algorithm input: "sha384.foo+bar:d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", algorithm: "sha384.foo+bar", encoded: "d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", err: ErrDigestUnsupported, }, { input: "sha384_foo+bar:d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", algorithm: "sha384_foo+bar", encoded: "d3fc7881460b7e22e3d172954463dddd7866d17597e7248453c48b3e9d26d9596bf9c4a9cf8072c9d5bad76e19af801d", err: ErrDigestUnsupported, }, { input: "sha256+b64:LCa0a2j_xo_5m0U8HTBBNBNCLXBkg7-g-YpeiGJm564", algorithm: "sha256+b64", encoded: "LCa0a2j_xo_5m0U8HTBBNBNCLXBkg7-g-YpeiGJm564", err: ErrDigestUnsupported, }, { input: "sha256:E58FCF7418D4390DEC8E8FB69D88C06EC07039D651FEDD3AA72AF9972E7D046B", err: ErrDigestInvalidFormat, }, } { digest, err := Parse(testcase.input) if err != testcase.err { t.Fatalf("error differed from expected while parsing %q: %v != %v", testcase.input, err, testcase.err) } if testcase.err != nil { continue } if digest.Algorithm() != testcase.algorithm { t.Fatalf("incorrect algorithm for parsed digest: %q != %q", digest.Algorithm(), testcase.algorithm) } if digest.Encoded() != testcase.encoded { t.Fatalf("incorrect hex for parsed digest: %q != %q", digest.Encoded(), testcase.encoded) } // Parse string return value and check equality newParsed, err := Parse(digest.String()) if err != nil { t.Fatalf("unexpected error parsing input %q: %v", testcase.input, err) } if newParsed != digest { t.Fatalf("expected equal: %q != %q", newParsed, digest) } newFromHex := NewDigestFromEncoded(newParsed.Algorithm(), newParsed.Encoded()) if newFromHex != digest { t.Fatalf("%v != %v", newFromHex, digest) } } } go-digest-1.0.0/digester.go000066400000000000000000000023021365712133000155250ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import "hash" // Digester calculates the digest of written data. Writes should go directly // to the return value of Hash, while calling Digest will return the current // value of the digest. type Digester interface { Hash() hash.Hash // provides direct access to underlying hash instance. Digest() Digest } // digester provides a simple digester definition that embeds a hasher. type digester struct { alg Algorithm hash hash.Hash } func (d *digester) Hash() hash.Hash { return d.hash } func (d *digester) Digest() Digest { return NewDigest(d.alg, d.hash) } go-digest-1.0.0/digestset/000077500000000000000000000000001365712133000153665ustar00rootroot00000000000000go-digest-1.0.0/digestset/set.go000066400000000000000000000163211365712133000165130ustar00rootroot00000000000000// Copyright 2020, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digestset import ( "errors" "sort" "strings" "sync" digest "github.com/opencontainers/go-digest" ) var ( // ErrDigestNotFound is used when a matching digest // could not be found in a set. ErrDigestNotFound = errors.New("digest not found") // ErrDigestAmbiguous is used when multiple digests // are found in a set. None of the matching digests // should be considered valid matches. ErrDigestAmbiguous = errors.New("ambiguous digest string") ) // Set is used to hold a unique set of digests which // may be easily referenced by easily referenced by a string // representation of the digest as well as short representation. // The uniqueness of the short representation is based on other // digests in the set. If digests are omitted from this set, // collisions in a larger set may not be detected, therefore it // is important to always do short representation lookups on // the complete set of digests. To mitigate collisions, an // appropriately long short code should be used. type Set struct { mutex sync.RWMutex entries digestEntries } // NewSet creates an empty set of digests // which may have digests added. func NewSet() *Set { return &Set{ entries: digestEntries{}, } } // checkShortMatch checks whether two digests match as either whole // values or short values. This function does not test equality, // rather whether the second value could match against the first // value. func checkShortMatch(alg digest.Algorithm, hex, shortAlg, shortHex string) bool { if len(hex) == len(shortHex) { if hex != shortHex { return false } if len(shortAlg) > 0 && string(alg) != shortAlg { return false } } else if !strings.HasPrefix(hex, shortHex) { return false } else if len(shortAlg) > 0 && string(alg) != shortAlg { return false } return true } // Lookup looks for a digest matching the given string representation. // If no digests could be found ErrDigestNotFound will be returned // with an empty digest value. If multiple matches are found // ErrDigestAmbiguous will be returned with an empty digest value. func (dst *Set) Lookup(d string) (digest.Digest, error) { dst.mutex.RLock() defer dst.mutex.RUnlock() if len(dst.entries) == 0 { return "", ErrDigestNotFound } var ( searchFunc func(int) bool alg digest.Algorithm hex string ) dgst, err := digest.Parse(d) if err == digest.ErrDigestInvalidFormat { hex = d searchFunc = func(i int) bool { return dst.entries[i].val >= d } } else { hex = dgst.Hex() alg = dgst.Algorithm() searchFunc = func(i int) bool { if dst.entries[i].val == hex { return dst.entries[i].alg >= alg } return dst.entries[i].val >= hex } } idx := sort.Search(len(dst.entries), searchFunc) if idx == len(dst.entries) || !checkShortMatch(dst.entries[idx].alg, dst.entries[idx].val, string(alg), hex) { return "", ErrDigestNotFound } if dst.entries[idx].alg == alg && dst.entries[idx].val == hex { return dst.entries[idx].digest, nil } if idx+1 < len(dst.entries) && checkShortMatch(dst.entries[idx+1].alg, dst.entries[idx+1].val, string(alg), hex) { return "", ErrDigestAmbiguous } return dst.entries[idx].digest, nil } // Add adds the given digest to the set. An error will be returned // if the given digest is invalid. If the digest already exists in the // set, this operation will be a no-op. func (dst *Set) Add(d digest.Digest) error { if err := d.Validate(); err != nil { return err } dst.mutex.Lock() defer dst.mutex.Unlock() entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d} searchFunc := func(i int) bool { if dst.entries[i].val == entry.val { return dst.entries[i].alg >= entry.alg } return dst.entries[i].val >= entry.val } idx := sort.Search(len(dst.entries), searchFunc) if idx == len(dst.entries) { dst.entries = append(dst.entries, entry) return nil } else if dst.entries[idx].digest == d { return nil } entries := append(dst.entries, nil) copy(entries[idx+1:], entries[idx:len(entries)-1]) entries[idx] = entry dst.entries = entries return nil } // Remove removes the given digest from the set. An err will be // returned if the given digest is invalid. If the digest does // not exist in the set, this operation will be a no-op. func (dst *Set) Remove(d digest.Digest) error { if err := d.Validate(); err != nil { return err } dst.mutex.Lock() defer dst.mutex.Unlock() entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d} searchFunc := func(i int) bool { if dst.entries[i].val == entry.val { return dst.entries[i].alg >= entry.alg } return dst.entries[i].val >= entry.val } idx := sort.Search(len(dst.entries), searchFunc) // Not found if idx is after or value at idx is not digest if idx == len(dst.entries) || dst.entries[idx].digest != d { return nil } entries := dst.entries copy(entries[idx:], entries[idx+1:]) entries = entries[:len(entries)-1] dst.entries = entries return nil } // All returns all the digests in the set func (dst *Set) All() []digest.Digest { dst.mutex.RLock() defer dst.mutex.RUnlock() retValues := make([]digest.Digest, len(dst.entries)) for i := range dst.entries { retValues[i] = dst.entries[i].digest } return retValues } // ShortCodeTable returns a map of Digest to unique short codes. The // length represents the minimum value, the maximum length may be the // entire value of digest if uniqueness cannot be achieved without the // full value. This function will attempt to make short codes as short // as possible to be unique. func ShortCodeTable(dst *Set, length int) map[digest.Digest]string { dst.mutex.RLock() defer dst.mutex.RUnlock() m := make(map[digest.Digest]string, len(dst.entries)) l := length resetIdx := 0 for i := 0; i < len(dst.entries); i++ { var short string extended := true for extended { extended = false if len(dst.entries[i].val) <= l { short = dst.entries[i].digest.String() } else { short = dst.entries[i].val[:l] for j := i + 1; j < len(dst.entries); j++ { if checkShortMatch(dst.entries[j].alg, dst.entries[j].val, "", short) { if j > resetIdx { resetIdx = j } extended = true } else { break } } if extended { l++ } } } m[dst.entries[i].digest] = short if i >= resetIdx { l = length } } return m } type digestEntry struct { alg digest.Algorithm val string digest digest.Digest } type digestEntries []*digestEntry func (d digestEntries) Len() int { return len(d) } func (d digestEntries) Less(i, j int) bool { if d[i].val != d[j].val { return d[i].val < d[j].val } return d[i].alg < d[j].alg } func (d digestEntries) Swap(i, j int) { d[i], d[j] = d[j], d[i] } go-digest-1.0.0/digestset/set_test.go000066400000000000000000000235121365712133000175520ustar00rootroot00000000000000// Copyright 2020, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digestset import ( "crypto/sha256" _ "crypto/sha512" "encoding/binary" "math/rand" "testing" digest "github.com/opencontainers/go-digest" ) func assertEqualDigests(t *testing.T, d1, d2 digest.Digest) { if d1 != d2 { t.Fatalf("Digests do not match:\n\tActual: %s\n\tExpected: %s", d1, d2) } } func TestLookup(t *testing.T) { digests := []digest.Digest{ "sha256:1234511111111111111111111111111111111111111111111111111111111111", "sha256:1234111111111111111111111111111111111111111111111111111111111111", "sha256:1234611111111111111111111111111111111111111111111111111111111111", "sha256:5432111111111111111111111111111111111111111111111111111111111111", "sha256:6543111111111111111111111111111111111111111111111111111111111111", "sha256:6432111111111111111111111111111111111111111111111111111111111111", "sha256:6542111111111111111111111111111111111111111111111111111111111111", "sha256:6532111111111111111111111111111111111111111111111111111111111111", } dset := NewSet() for i := range digests { if err := dset.Add(digests[i]); err != nil { t.Fatal(err) } } dgst, err := dset.Lookup("54") if err != nil { t.Fatal(err) } assertEqualDigests(t, dgst, digests[3]) _, err = dset.Lookup("1234") if err == nil { t.Fatal("Expected ambiguous error looking up: 1234") } if err != ErrDigestAmbiguous { t.Fatal(err) } _, err = dset.Lookup("9876") if err == nil { t.Fatal("Expected not found error looking up: 9876") } if err != ErrDigestNotFound { t.Fatal(err) } _, err = dset.Lookup("sha256:1234") if err == nil { t.Fatal("Expected ambiguous error looking up: sha256:1234") } if err != ErrDigestAmbiguous { t.Fatal(err) } dgst, err = dset.Lookup("sha256:12345") if err != nil { t.Fatal(err) } assertEqualDigests(t, dgst, digests[0]) dgst, err = dset.Lookup("sha256:12346") if err != nil { t.Fatal(err) } assertEqualDigests(t, dgst, digests[2]) dgst, err = dset.Lookup("12346") if err != nil { t.Fatal(err) } assertEqualDigests(t, dgst, digests[2]) dgst, err = dset.Lookup("12345") if err != nil { t.Fatal(err) } assertEqualDigests(t, dgst, digests[0]) } func TestAddDuplication(t *testing.T) { digests := []digest.Digest{ "sha256:1234111111111111111111111111111111111111111111111111111111111111", "sha256:1234511111111111111111111111111111111111111111111111111111111111", "sha256:1234611111111111111111111111111111111111111111111111111111111111", "sha256:5432111111111111111111111111111111111111111111111111111111111111", "sha256:6543111111111111111111111111111111111111111111111111111111111111", "sha512:65431111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111", "sha512:65421111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111", "sha512:65321111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111", } dset := NewSet() for i := range digests { if err := dset.Add(digests[i]); err != nil { t.Fatal(err) } } if len(dset.entries) != 8 { t.Fatal("Invalid dset size") } if err := dset.Add(digest.Digest("sha256:1234511111111111111111111111111111111111111111111111111111111111")); err != nil { t.Fatal(err) } if len(dset.entries) != 8 { t.Fatal("Duplicate digest insert should not increase entries size") } if err := dset.Add(digest.Digest("sha384:123451111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111")); err != nil { t.Fatal(err) } if len(dset.entries) != 9 { t.Fatal("Insert with different algorithm should be allowed") } } func TestRemove(t *testing.T) { digests, err := createDigests(10) if err != nil { t.Fatal(err) } dset := NewSet() for i := range digests { if err := dset.Add(digests[i]); err != nil { t.Fatal(err) } } dgst, err := dset.Lookup(digests[0].String()) if err != nil { t.Fatal(err) } if dgst != digests[0] { t.Fatalf("Unexpected digest value:\n\tExpected: %s\n\tActual: %s", digests[0], dgst) } if err := dset.Remove(digests[0]); err != nil { t.Fatal(err) } if _, err := dset.Lookup(digests[0].String()); err != ErrDigestNotFound { t.Fatalf("Expected error %v when looking up removed digest, got %v", ErrDigestNotFound, err) } } func TestAll(t *testing.T) { digests, err := createDigests(100) if err != nil { t.Fatal(err) } dset := NewSet() for i := range digests { if err := dset.Add(digests[i]); err != nil { t.Fatal(err) } } all := map[digest.Digest]struct{}{} for _, dgst := range dset.All() { all[dgst] = struct{}{} } if len(all) != len(digests) { t.Fatalf("Unexpected number of unique digests found:\n\tExpected: %d\n\tActual: %d", len(digests), len(all)) } for i, dgst := range digests { if _, ok := all[dgst]; !ok { t.Fatalf("Missing element at position %d: %s", i, dgst) } } } func assertEqualShort(t *testing.T, actual, expected string) { if actual != expected { t.Fatalf("Unexpected short value:\n\tExpected: %s\n\tActual: %s", expected, actual) } } func TestShortCodeTable(t *testing.T) { digests := []digest.Digest{ "sha256:1234111111111111111111111111111111111111111111111111111111111111", "sha256:1234511111111111111111111111111111111111111111111111111111111111", "sha256:1234611111111111111111111111111111111111111111111111111111111111", "sha256:5432111111111111111111111111111111111111111111111111111111111111", "sha256:6543111111111111111111111111111111111111111111111111111111111111", "sha256:6432111111111111111111111111111111111111111111111111111111111111", "sha256:6542111111111111111111111111111111111111111111111111111111111111", "sha256:6532111111111111111111111111111111111111111111111111111111111111", } dset := NewSet() for i := range digests { if err := dset.Add(digests[i]); err != nil { t.Fatal(err) } } dump := ShortCodeTable(dset, 2) if len(dump) < len(digests) { t.Fatalf("Error unexpected size: %d, expecting %d", len(dump), len(digests)) } assertEqualShort(t, dump[digests[0]], "12341") assertEqualShort(t, dump[digests[1]], "12345") assertEqualShort(t, dump[digests[2]], "12346") assertEqualShort(t, dump[digests[3]], "54") assertEqualShort(t, dump[digests[4]], "6543") assertEqualShort(t, dump[digests[5]], "64") assertEqualShort(t, dump[digests[6]], "6542") assertEqualShort(t, dump[digests[7]], "653") } func createDigests(count int) ([]digest.Digest, error) { r := rand.New(rand.NewSource(25823)) digests := make([]digest.Digest, count) for i := range digests { h := sha256.New() if err := binary.Write(h, binary.BigEndian, r.Int63()); err != nil { return nil, err } digests[i] = digest.NewDigest("sha256", h) } return digests, nil } func benchAddNTable(b *testing.B, n int) { digests, err := createDigests(n) if err != nil { b.Fatal(err) } b.ResetTimer() for i := 0; i < b.N; i++ { dset := &Set{entries: digestEntries(make([]*digestEntry, 0, n))} for j := range digests { if err = dset.Add(digests[j]); err != nil { b.Fatal(err) } } } } func benchLookupNTable(b *testing.B, n int, shortLen int) { digests, err := createDigests(n) if err != nil { b.Fatal(err) } dset := &Set{entries: digestEntries(make([]*digestEntry, 0, n))} for i := range digests { if err := dset.Add(digests[i]); err != nil { b.Fatal(err) } } shorts := make([]string, 0, n) for _, short := range ShortCodeTable(dset, shortLen) { shorts = append(shorts, short) } b.ResetTimer() for i := 0; i < b.N; i++ { if _, err = dset.Lookup(shorts[i%n]); err != nil { b.Fatal(err) } } } func benchRemoveNTable(b *testing.B, n int) { digests, err := createDigests(n) if err != nil { b.Fatal(err) } b.ResetTimer() for i := 0; i < b.N; i++ { dset := &Set{entries: digestEntries(make([]*digestEntry, 0, n))} b.StopTimer() for j := range digests { if err = dset.Add(digests[j]); err != nil { b.Fatal(err) } } b.StartTimer() for j := range digests { if err = dset.Remove(digests[j]); err != nil { b.Fatal(err) } } } } func benchShortCodeNTable(b *testing.B, n int, shortLen int) { digests, err := createDigests(n) if err != nil { b.Fatal(err) } dset := &Set{entries: digestEntries(make([]*digestEntry, 0, n))} for i := range digests { if err := dset.Add(digests[i]); err != nil { b.Fatal(err) } } b.ResetTimer() for i := 0; i < b.N; i++ { ShortCodeTable(dset, shortLen) } } func BenchmarkAdd10(b *testing.B) { benchAddNTable(b, 10) } func BenchmarkAdd100(b *testing.B) { benchAddNTable(b, 100) } func BenchmarkAdd1000(b *testing.B) { benchAddNTable(b, 1000) } func BenchmarkRemove10(b *testing.B) { benchRemoveNTable(b, 10) } func BenchmarkRemove100(b *testing.B) { benchRemoveNTable(b, 100) } func BenchmarkRemove1000(b *testing.B) { benchRemoveNTable(b, 1000) } func BenchmarkLookup10(b *testing.B) { benchLookupNTable(b, 10, 12) } func BenchmarkLookup100(b *testing.B) { benchLookupNTable(b, 100, 12) } func BenchmarkLookup1000(b *testing.B) { benchLookupNTable(b, 1000, 12) } func BenchmarkShortCode10(b *testing.B) { benchShortCodeNTable(b, 10, 12) } func BenchmarkShortCode100(b *testing.B) { benchShortCodeNTable(b, 100, 12) } func BenchmarkShortCode1000(b *testing.B) { benchShortCodeNTable(b, 1000, 12) } go-digest-1.0.0/doc.go000066400000000000000000000047641365712133000145020ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. // Package digest provides a generalized type to opaquely represent message // digests and their operations within the registry. The Digest type is // designed to serve as a flexible identifier in a content-addressable system. // More importantly, it provides tools and wrappers to work with // hash.Hash-based digests with little effort. // // Basics // // The format of a digest is simply a string with two parts, dubbed the // "algorithm" and the "digest", separated by a colon: // // : // // An example of a sha256 digest representation follows: // // sha256:7173b809ca12ec5dee4506cd86be934c4596dd234ee82c0662eac04a8c2c71dc // // The "algorithm" portion defines both the hashing algorithm used to calculate // the digest and the encoding of the resulting digest, which defaults to "hex" // if not otherwise specified. Currently, all supported algorithms have their // digests encoded in hex strings. // // In the example above, the string "sha256" is the algorithm and the hex bytes // are the "digest". // // Because the Digest type is simply a string, once a valid Digest is // obtained, comparisons are cheap, quick and simple to express with the // standard equality operator. // // Verification // // The main benefit of using the Digest type is simple verification against a // given digest. The Verifier interface, modeled after the stdlib hash.Hash // interface, provides a common write sink for digest verification. After // writing is complete, calling the Verifier.Verified method will indicate // whether or not the stream of bytes matches the target digest. // // Missing Features // // In addition to the above, we intend to add the following features to this // package: // // 1. A Digester type that supports write sink digest calculation. // // 2. Suspend and resume of ongoing digest calculations to support efficient digest verification in the registry. // package digest go-digest-1.0.0/go.mod000066400000000000000000000000641365712133000145010ustar00rootroot00000000000000module github.com/opencontainers/go-digest go 1.13 go-digest-1.0.0/releases/000077500000000000000000000000001365712133000151765ustar00rootroot00000000000000go-digest-1.0.0/releases/README.md000066400000000000000000000052411365712133000164570ustar00rootroot00000000000000## go-digest release process 1. Create release pull request with release notes and updated versions. 1. Compile release notes detailing features added since the last release and add release template file to `releases/` directory. The template is defined by containerd's release tool but refer to previous release files for style and format help. Name the file using the version, for rc add an `-rc` suffix. When moving from rc to final, the rc file may just be renamed and updated. See [release-tool](https://github.com/containerd/release-tool) 2. Update the `.mailmap` files for commit authors which have multiple email addresses in the commit log. If it is not clear which email or name the contributor might want used in the release notes, reach out to the contributor for feedback. NOTE: real names should be used whenever possible. The file is maintained by manually adding entries to the file. - e.g. `Real Name Other Name ` 3. Before opening the pull request, run the release tool using the new release notes. Ensure the output matches what is expected, including contributors, change log, dependencies, and visual elements such as spacing. If a contributor is duplicated, use the emails outputted by the release tool to update the mailmap then re-run. The goal of the release tool is that is generates release notes that need no alterations after it is generated. 2. Create tag 1. Choose tag for the next release, go-digest uses semantic versioning and expects tags to be formatted as `vx.y.z[-rc.n]`. 2. Generate release notes (using a temp file may be helpful). - e.g. `release-tool -l -d -n -t v1.0.0 ./releases/v1.0.0.toml > /tmp/v1.0.0-notes` 3. Create tag using the generated release notes. - e.g. `git tag --cleanup=whitespace -s v1.0.0 -F /tmp/v1.0.0-notes` 4. Verify tag (e.g. `git show v1.0.0`), it may help to compare the new tag against previous. 3. Push tag and Github release 1. Push the tag to `git@github.com:opencontainers/go-digest.git`. NOTE: this will kick off CI building of the release binaries. 2. Create the Github release using the `Tag version` which was just pushed. Use the first line outputted from the release tool as the `Release title` and the remainder of the output for the description. No alteration of the release output should be needed. Ensure `pre-release` is checked if an `-rc`. NOTE: This should be done immediately after pushing the tag, otherwise CI may create the release when the binaries are pushed. 4. Promote on Slack, Twitter, mailing lists, etc go-digest-1.0.0/releases/v1.0.0.toml000066400000000000000000000015521365712133000167200ustar00rootroot00000000000000# commit to be tagged for new release commit = "HEAD" project_name = "go-digest" github_repo = "opencontainers/go-digest" pre_release = false preface = """\ This is the first official release of the go-digest package. This package provides a simple toolkit for working with the digests used in the open containers ecosystem. This includes support for `sha256`, `sha384`, and `sha512` algorithms, with `sha256` being the most common and preferred for greatest compatibility across the ecosystem. Encoding ambiguity has been removed by only supporting lower case hex-encoded characters in the format for this release. The `digestset` package is provided to securely and unambiguously use shortened forms of the digest in environments where there is a full set of known digests.""" # notable prs to include in the release notes, 1234 is the pr number [notes] [breaking] go-digest-1.0.0/verifiers.go000066400000000000000000000025101365712133000157160ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "hash" "io" ) // Verifier presents a general verification interface to be used with message // digests and other byte stream verifications. Users instantiate a Verifier // from one of the various methods, write the data under test to it then check // the result with the Verified method. type Verifier interface { io.Writer // Verified will return true if the content written to Verifier matches // the digest. Verified() bool } type hashVerifier struct { digest Digest hash hash.Hash } func (hv hashVerifier) Write(p []byte) (n int, err error) { return hv.hash.Write(p) } func (hv hashVerifier) Verified() bool { return hv.digest == NewDigest(hv.digest.Algorithm(), hv.hash) } go-digest-1.0.0/verifiers_test.go000066400000000000000000000040301365712133000167540ustar00rootroot00000000000000// Copyright 2019, 2020 OCI Contributors // Copyright 2017 Docker, Inc. // // 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 // // https://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. package digest import ( "bytes" "crypto/rand" "io" "reflect" "testing" ) func TestDigestVerifier(t *testing.T) { p := make([]byte, 1<<20) rand.Read(p) digest := FromBytes(p) verifier := digest.Verifier() io.Copy(verifier, bytes.NewReader(p)) if !verifier.Verified() { t.Fatalf("bytes not verified") } } // TestVerifierUnsupportedDigest ensures that unsupported digest validation is // flowing through verifier creation. func TestVerifierUnsupportedDigest(t *testing.T) { for _, testcase := range []struct { Name string Digest Digest Expected interface{} // expected panic target }{ { Name: "Empty", Digest: "", Expected: "no ':' separator in digest \"\"", }, { Name: "EmptyAlg", Digest: ":", Expected: "empty digest algorithm, validate before calling Algorithm.Hash()", }, { Name: "Unsupported", Digest: Digest("bean:0123456789abcdef"), Expected: "bean not available (make sure it is imported)", }, { Name: "Garbage", Digest: Digest("sha256-garbage:pure"), Expected: "sha256-garbage not available (make sure it is imported)", }, } { t.Run(testcase.Name, func(t *testing.T) { expected := testcase.Expected defer func() { recovered := recover() if !reflect.DeepEqual(recovered, expected) { t.Fatalf("unexpected recover: %v != %v", recovered, expected) } }() _ = testcase.Digest.Verifier() }) } }