├── test ├── fixtures │ └── wtf.jpg ├── rel.js ├── hashing.js └── parsing-cids.js ├── src ├── index.ts ├── hash.ts ├── codecs.ts └── parse-cid.ts ├── TODO.md ├── tsconfig.json ├── package.json ├── README.md ├── .gitignore └── LICENSE /test/fixtures/wtf.jpg: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/darobin/catboat/main/test/fixtures/wtf.jpg -------------------------------------------------------------------------------- /src/index.ts: -------------------------------------------------------------------------------- 1 | 2 | export { default as parseCID, CID } from './parse-cid.js'; 3 | export { default as hash } from './hash.js'; 4 | 5 | export * from './codecs.js'; 6 | -------------------------------------------------------------------------------- /src/hash.ts: -------------------------------------------------------------------------------- 1 | 2 | import { blake3 } from 'hash-wasm'; 3 | 4 | export default async function hash (arr: Uint8Array): Promise { 5 | return await blake3(arr); 6 | } 7 | -------------------------------------------------------------------------------- /src/codecs.ts: -------------------------------------------------------------------------------- 1 | 2 | const enum CIDCodec { 3 | raw = 0x55, 4 | dagCBOR = 0x71, 5 | }; 6 | const CODECS = { 7 | raw: CIDCodec.raw, 8 | dagCBOR: CIDCodec.dagCBOR, 9 | }; 10 | 11 | export { CODECS, CIDCodec }; 12 | -------------------------------------------------------------------------------- /test/rel.js: -------------------------------------------------------------------------------- 1 | 2 | // call with makeRel(import.meta.url), returns a function that resolves relative paths 3 | export default function makeRel (importURL) { 4 | return (pth) => new URL(pth, importURL).toString().replace(/^file:\/\//, ''); 5 | } 6 | -------------------------------------------------------------------------------- /TODO.md: -------------------------------------------------------------------------------- 1 | 2 | # TODO 3 | - [x] parse-cid 4 | - [x] hash (internals to make Blake3 hashes easily) 5 | - [ ] cid`` 6 | - [ ] TS 7 | - [ ] test 8 | - [ ] docs 9 | - [ ] make-cid 10 | - [ ] TS 11 | - [ ] test 12 | - [ ] docs 13 | - [ ] dcbor42 14 | - [ ] TS 15 | - [ ] test 16 | - [ ] docs 17 | -------------------------------------------------------------------------------- /tsconfig.json: -------------------------------------------------------------------------------- 1 | { 2 | "compilerOptions": { 3 | "declaration": true, 4 | "declarationDir": "dist/types", 5 | "esModuleInterop": true, 6 | "lib": ["ES2021"], 7 | "module": "ESNext", 8 | "moduleResolution": "Node", 9 | "outDir": "dist/esm", 10 | "target": "ES2021" 11 | }, 12 | "tsc-alias": { 13 | "resolveFullPaths": true, 14 | "verbose": true 15 | }, 16 | "include": ["src"], 17 | "exclude": ["node_modules", "test"] 18 | } 19 | -------------------------------------------------------------------------------- /test/hashing.js: -------------------------------------------------------------------------------- 1 | 2 | import { equal } from 'node:assert'; 3 | import { readFile } from 'node:fs/promises'; 4 | import makeRel from './rel.js'; 5 | import { hash } from "catboat"; 6 | 7 | const rel = makeRel(import.meta.url); 8 | 9 | let wtfData, wtfHash; 10 | before(async () => { 11 | wtfData = await readFile(rel('fixtures/wtf.jpg')); 12 | wtfHash = await hash(wtfData); 13 | }); 14 | describe('Blake3 Hashing', () => { 15 | it('hashes correctly', () => { 16 | equal('62c6f749c80a27813a84066b92a6fdc37fd83779bf9d64f1f1a3692cf3a7dfbd', wtfHash, 'hash matches'); 17 | }); 18 | }); 19 | -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "catboat", 3 | "type": "module", 4 | "version": "0.2.0", 5 | "description": "Content Addressing Toolbox Of Assorted Tools", 6 | "author": "Robin Berjon ", 7 | "license": "Apache-2.0", 8 | "main": "./dist/cjs/index.js", 9 | "module": "./dist/esm/index.js", 10 | "types": "./dist/types/index.d.ts", 11 | "files": [ 12 | "dist" 13 | ], 14 | "exports": { 15 | "./package.json": "./package.json", 16 | ".": { 17 | "types": "./dist/types/index.d.ts", 18 | "require": "./dist/cjs/index.js", 19 | "import": "./dist/esm/index.js" 20 | } 21 | }, 22 | "scripts": { 23 | "watch": "tsc --watch", 24 | "build": "tsc && tsc-alias -p tsconfig.json", 25 | "postbuild": "esm2cjs --in dist/esm --out dist/cjs -l error", 26 | "release": "npm run build && release-it", 27 | "test": "mocha" 28 | }, 29 | "bin": {}, 30 | "repository": { 31 | "type": "git", 32 | "url": "https://github.com/darobin/catboat.git" 33 | }, 34 | "eslintConfig": { 35 | "env": { 36 | "browser": true, 37 | "mocha": true, 38 | "es2021": true 39 | }, 40 | "extends": "eslint:recommended", 41 | "overrides": [], 42 | "parserOptions": { 43 | "ecmaVersion": "latest", 44 | "sourceType": "module" 45 | }, 46 | "rules": {} 47 | }, 48 | "devDependencies": { 49 | "@alcalzone/esm2cjs": "^1.1.2", 50 | "@types/node": "^22.7.6", 51 | "eslint": "^8.26.0", 52 | "mocha": "^10.7.3", 53 | "tsc-alias": "^1.8.10", 54 | "typescript": "^5.6.3" 55 | }, 56 | "dependencies": { 57 | "hash-wasm": "^4.11.0" 58 | } 59 | } 60 | -------------------------------------------------------------------------------- /test/parsing-cids.js: -------------------------------------------------------------------------------- 1 | 2 | import { equal, throws } from 'node:assert'; 3 | import { readFile } from 'node:fs/promises'; 4 | import makeRel from './rel.js'; 5 | import { parseCID, hash, CODECS } from "catboat"; 6 | 7 | const rel = makeRel(import.meta.url); 8 | 9 | let wtfData, wtfHash; 10 | const wtf = 'k2cx9is2yavhu7l74wtw7enigx8xyikvkyhnqjz8xgk5reer38v91jul'; 11 | // base36 - cidv1 - raw - (blake3 : 256 : 62C6F749C80A27813A84066B92A6FDC37FD83779BF9D64F1F1A3692CF3A7DFBD) 12 | 13 | before(async () => { 14 | wtfData = await readFile(rel('fixtures/wtf.jpg')); 15 | wtfHash = await hash(wtfData); 16 | }); 17 | describe('CID parsing', () => { 18 | it('parses a valid CID', () => { 19 | const { version, codec, hash, hashType } = parseCID(wtf); 20 | equal(version, 1, 'version must be 1'); 21 | equal(codec, CODECS.raw, 'codec must be raw'); 22 | equal(hashType, 'blake3', 'hash type must be blake3'); 23 | equal(hash, wtfHash, 'hash must be the right one'); 24 | }); 25 | it('refuses to parse invalid LUCIDs', () => { 26 | throws(() => parseCID('QmNprJ78ovcUuGMoMFiihK7GBpCmH578JU8hm43uxYQtBw'), /CIDv0 is not supported/, 'no v0'); 27 | throws(() => parseCID('zb2rhe5P4gXftAwvA4eXQ5HJwsER2owDyS9sKaQRRVQPn93bA'), /Only base36 lowercase is supported/, 'only b36'); 28 | throws(() => parseCID('k'), /Empty CID/, 'no empty'); 29 | throws(() => parseCID('k4cx9is2yavhu7l74wtw7enigx8xyikvkyhnqjz8xgk5reer38v91jul'), /Only version 1 is supported/, 'no v2'); 30 | throws(() => parseCID('k2jn92crxvj3lh7ekv0mwv4gul75xzm141qiz5dhx9clipbs3eusi3vg'), /Unsupported CID codec/, 'limited codecs'); 31 | throws(() => parseCID('k2cwuedmosc65hhh0bee97q5jx3fe55tiyqzep8vgds83agps9dof3da'), /The only supported hash type is Blake3/, 'only blake3'); 32 | // XXX Not testing the below yet 33 | // throws(() => parseCID('bafkr4ejfguvoa2fvjkj66yeufqef3ir2ginh66mfde4raiq42t7775p7wy'), /Wrong size for Blake3 hash/, 'wrong blake3'); 34 | }); 35 | }); 36 | 37 | // describe('CID minting', () => { 38 | // it('mints a valid CID for bytes', async () => { 39 | // const cid = await fromRaw(wtfData); 40 | // equal(cid, wtf, 'CID is correct'); 41 | // }); 42 | // }); 43 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | 2 | # catboat — Content Addressing ToolBox Of Assorted Tools 3 | 4 | Catboat is a batteries-included and opinionated yet lightweight toolbox for operating or 5 | interacting with a content addressing system. The approach taken can be summarised as: 6 | 7 | 1. Optionality increases implementation cost and hurts interoperability. As much as possible 8 | Catboat only supports one way of doing anything (though extensibility points exist). 9 | 2. Flexible power comes from assembling small bricks that do one thing well. Every piece of 10 | functionality is self-contained but designed to play well with others. 11 | 3. It has no DHT and therefore it works. Instead of relying on a global DHT that is hard to 12 | maintain and has poor latency, Catboat is meant to integrate with existing transports 13 | such as HTTPS, Iroh, or ATProto. 14 | 15 | Both ESM and CJS modules are provided, as well as Typescript types. 16 | 17 | ## API 18 | 19 | ### `CID = parseCID(cid)` 20 | 21 | ```js 22 | import { parseCID } from 'catboat'; 23 | // or import parseCID from 'catboat/parse-cid'; 24 | 25 | const cid = parseCID('k2cx9is2yavhu7l74wtw7enigx8xyikvkyhnqjz8xgk5reer38v91jul'); 26 | ``` 27 | 28 | Takes a CID (Content IDentifier) and parses it into its component parts: 29 | - `version`: always `1`. 30 | - `codec`: either `CIDCodec.raw` (`0x55`) or `CIDCodec.dagCBOR` (`0x71`). 31 | - `hash`: a lowercase-hex string representing the hash. 32 | - `hashType`: always `blake3`. 33 | 34 | Throws if the CID is invalid. 35 | 36 | The CIDs we use are a compatible strict-subset of IPFS CIDs. Most IPFS CIDs will 37 | be rejected but the CIDs that Catboat supports all work with IPFS systems. They are 38 | constrained to being: 39 | 40 | 1. Only v1, no v0. 41 | 2. Only base36 multibase lowercase encoding (the k prefix) for the string, human-readable encoding. 42 | 3. Only the raw-binary codec (0x55) and dag-cbor (0x71). 43 | 4. Only Blake3 hashes (0x1e). 44 | 5. No blocks. 45 | 6. This set of options has the added advantage that no varint processing is required. 46 | 47 | These are known as "LUCIDs" which stands for "Lightweight Universal CIDs." 48 | 49 | ### `stringHash = await hash(uint8Arr)` 50 | 51 | ```js 52 | import { hash } from 'catboat'; 53 | // or import hash from 'catboat/hash'; 54 | 55 | const h = await hash(someBytes); 56 | ``` 57 | 58 | Takes a `Uint8Array` of bytes and returns a promise that resolves to a lowercase-hex representation 59 | of the Blake3 hash. 60 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Logs 2 | logs 3 | *.log 4 | npm-debug.log* 5 | yarn-debug.log* 6 | yarn-error.log* 7 | lerna-debug.log* 8 | .pnpm-debug.log* 9 | 10 | # Diagnostic reports (https://nodejs.org/api/report.html) 11 | report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json 12 | 13 | # Runtime data 14 | pids 15 | *.pid 16 | *.seed 17 | *.pid.lock 18 | 19 | # Directory for instrumented libs generated by jscoverage/JSCover 20 | lib-cov 21 | 22 | # Coverage directory used by tools like istanbul 23 | coverage 24 | *.lcov 25 | 26 | # nyc test coverage 27 | .nyc_output 28 | 29 | # Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files) 30 | .grunt 31 | 32 | # Bower dependency directory (https://bower.io/) 33 | bower_components 34 | 35 | # node-waf configuration 36 | .lock-wscript 37 | 38 | # Compiled binary addons (https://nodejs.org/api/addons.html) 39 | build/Release 40 | 41 | # Dependency directories 42 | node_modules/ 43 | jspm_packages/ 44 | 45 | # Snowpack dependency directory (https://snowpack.dev/) 46 | web_modules/ 47 | 48 | # TypeScript cache 49 | *.tsbuildinfo 50 | 51 | # Optional npm cache directory 52 | .npm 53 | 54 | # Optional eslint cache 55 | .eslintcache 56 | 57 | # Optional stylelint cache 58 | .stylelintcache 59 | 60 | # Microbundle cache 61 | .rpt2_cache/ 62 | .rts2_cache_cjs/ 63 | .rts2_cache_es/ 64 | .rts2_cache_umd/ 65 | 66 | # Optional REPL history 67 | .node_repl_history 68 | 69 | # Output of 'npm pack' 70 | *.tgz 71 | 72 | # Yarn Integrity file 73 | .yarn-integrity 74 | 75 | # dotenv environment variable files 76 | .env 77 | .env.development.local 78 | .env.test.local 79 | .env.production.local 80 | .env.local 81 | 82 | # parcel-bundler cache (https://parceljs.org/) 83 | .cache 84 | .parcel-cache 85 | 86 | # Next.js build output 87 | .next 88 | out 89 | 90 | # Nuxt.js build / generate output 91 | .nuxt 92 | dist 93 | 94 | # Gatsby files 95 | .cache/ 96 | # Comment in the public line in if your project uses Gatsby and not Next.js 97 | # https://nextjs.org/blog/next-9-1#public-directory-support 98 | # public 99 | 100 | # vuepress build output 101 | .vuepress/dist 102 | 103 | # vuepress v2.x temp and cache directory 104 | .temp 105 | .cache 106 | 107 | # Docusaurus cache and generated files 108 | .docusaurus 109 | 110 | # Serverless directories 111 | .serverless/ 112 | 113 | # FuseBox cache 114 | .fusebox/ 115 | 116 | # DynamoDB Local files 117 | .dynamodb/ 118 | 119 | # TernJS port file 120 | .tern-port 121 | 122 | # Stores VSCode versions used for testing VSCode extensions 123 | .vscode-test 124 | 125 | # yarn v2 126 | .yarn/cache 127 | .yarn/unplugged 128 | .yarn/build-state.yml 129 | .yarn/install-state.gz 130 | .pnp.* 131 | scratch/ 132 | -------------------------------------------------------------------------------- /src/parse-cid.ts: -------------------------------------------------------------------------------- 1 | 2 | import { CODECS, CIDCodec } from './codecs.js'; 3 | 4 | // Code heavily inspired by js-multiformats, which vendors the following: 5 | // base-x encoding / decoding 6 | // Copyright (c) 2018 base-x contributors 7 | // Copyright (c) 2014-2018 The Bitcoin Core developers (base58.cpp) 8 | // Distributed under the MIT software license, see 9 | // http://www.opensource.org/licenses/mit-license.php. 10 | 11 | 12 | const B36_ALPHABET = '0123456789abcdefghijklmnopqrstuvwxyz'; 13 | 14 | const BASE = 36; 15 | const LEADER = '0'; 16 | const FACTOR = Math.log(BASE) / Math.log(256); 17 | 18 | const BASE_MAP = new Uint8Array(256); 19 | for (let i = 0; i < BASE_MAP.length; i++) BASE_MAP[i] = 255; 20 | for (let i = 0; i < B36_ALPHABET.length; i++) { 21 | BASE_MAP[B36_ALPHABET.charAt(i).charCodeAt(0)] = i; 22 | } 23 | 24 | const SUPPORTED_CODECS = new Set(Object.values(CODECS)); 25 | 26 | const BLAKE3_CODE = 0x1e; 27 | const BLAKE3_SIZE = 32; 28 | 29 | // Gets a CID as string or Uint8Array. 30 | // Returns a structure with all components. 31 | // Throws if we don't support it. 32 | export default function parse (cid: string | Uint8Array): CID { 33 | let uarr: Uint8Array; 34 | if (typeof cid === 'string') { 35 | if (cid.length === 46 && /^Qm/.test(cid)) throw new Error('CIDv0 is not supported'); 36 | if (cid[0] !== 'k') throw new Error('Only base36 lowercase is supported'); 37 | cid = cid.substring(1); 38 | if (cid.length === 0) throw new Error('Empty CID'); 39 | let psz = 0; 40 | let zeroes = 0; 41 | let length = 0; 42 | while (cid[psz] === LEADER) { 43 | zeroes++; 44 | psz++; 45 | } 46 | const size = (((cid.length - psz) * FACTOR) + 1) >>> 0; 47 | const b256 = new Uint8Array(size); 48 | while (cid[psz]) { 49 | let carry = BASE_MAP[cid.charCodeAt(psz)]; 50 | if (carry === 255) return; 51 | let i = 0; 52 | for (let it3 = size - 1; (carry !== 0 || i < length) && (it3 !== -1); it3--, i++) { 53 | carry += (BASE * b256[it3]) >>> 0; 54 | b256[it3] = (carry % 256) >>> 0; 55 | carry = (carry / 256) >>> 0; 56 | } 57 | if (carry !== 0) throw new Error('Non-zero carry'); 58 | length = i; 59 | psz++; 60 | } 61 | let it4 = size - length; 62 | while (it4 !== size && b256[it4] === 0) it4++; 63 | const vch = new Uint8Array(zeroes + (size - it4)); 64 | let j = zeroes; 65 | while (it4 !== size) vch[j++] = b256[it4++]; 66 | uarr = vch; 67 | } 68 | else { 69 | uarr = cid; 70 | } 71 | // IMPORTANT: we don't process varints because for now we don't need to. See details on makeCID(). 72 | const version: CIDVersion = uarr[0]; 73 | if (version !== 1) throw new Error(`Only version 1 is supported, got ${version}.`); 74 | const codec: CIDCodec = uarr[1]; 75 | if (!SUPPORTED_CODECS.has(codec)) throw new Error(`Unsupported CID codec ${codec}`); 76 | const multihashBytes = uarr.slice(2); 77 | if (multihashBytes[0] !== BLAKE3_CODE) throw new Error(`The only supported hash type is Blake3, got "${multihashBytes[0]}".`); 78 | if (multihashBytes[1] !== BLAKE3_SIZE) throw new Error('Wrong size for Blake3 hash.'); 79 | const hash = multihashBytes.slice(2).reduce((hex, byte) => hex + byte.toString(16).padStart(2, '0'), ''); 80 | return { version, codec, hash, hashType: CIDHashType.blake3 }; 81 | } 82 | 83 | enum CIDVersion { 84 | v1 = 1, 85 | }; 86 | enum CIDHashType { 87 | blake3 = 'blake3', 88 | } 89 | 90 | export type CID = { 91 | version: CIDVersion, 92 | codec: CIDCodec, 93 | hash: string, 94 | hashType: CIDHashType, 95 | }; 96 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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