feat: add sha1 support

It's old and insecure but it's used in the wild so we need to be
able to handle it.

package.json

@@ -148,6 +148,11 @@
       "types": "./dist/types/src/hashes/interface.d.ts",
       "import": "./src/hashes/interface.js"
     },
+    "./hashes/sha1": {
+      "types": "./dist/types/src/hashes/sha1.d.ts",
+      "browser": "./src/hashes/sha1-browser.js",
+      "import": "./src/hashes/sha1.js"
+    },
     "./hashes/sha2": {
       "types": "./dist/types/src/hashes/sha2.d.ts",
       "browser": "./src/hashes/sha2-browser.js",
@@ -171,6 +176,8 @@
     }
   },
   "browser": {
+    "./hashes/sha1": "./src/hashes/sha1-browser.js",
+    "./src/hashes/sha1.js": "./src/hashes/sha1-browser.js",
     "./hashes/sha2": "./src/hashes/sha2-browser.js",
     "./src/hashes/sha2.js": "./src/hashes/sha2-browser.js"
   },
@@ -286,7 +293,8 @@
     "@types/node": "^18.0.0",
     "aegir": "^37.7.5",
     "buffer": "^6.0.3",
-    "cids": "^1.1.9"
+    "cids": "^1.1.9",
+    "crypto-hash": "^2.0.1"
   },
   "aegir": {
     "test": {

src/hashes/sha1-browser.js

@@ -0,0 +1,18 @@
+/* global crypto */
+
+import { from } from './hasher.js'
+
+/**
+ * @param {AlgorithmIdentifier} name
+ */
+const sha = name =>
+  /**
+   * @param {Uint8Array} data
+   */
+  async data => new Uint8Array(await crypto.subtle.digest(name, data))
+
+export const sha1 = from({
+  name: 'sha-1',
+  code: 0x11,
+  encode: sha('SHA-1')
+})

src/hashes/sha1.js

@@ -0,0 +1,11 @@
+// @ts-check
+
+import crypto from 'crypto'
+import { from } from './hasher.js'
+import { coerce } from '../bytes.js'
+
+export const sha1 = from({
+  name: 'sha-1',
+  code: 0x11,
+  encode: (input) => coerce(crypto.createHash('sha1').update(input).digest())
+})

test/test-multihash.spec.js

@@ -1,10 +1,12 @@
 /* globals describe, it */
 import { fromHex, fromString } from '../src/bytes.js'
 import { sha256, sha512 } from '../src/hashes/sha2.js'
+import { sha1 } from '../src/hashes/sha1.js'
 import { identity } from '../src/hashes/identity.js'
 import { decode as decodeDigest, create as createDigest } from '../src/hashes/digest.js'
 import valid from './fixtures/valid-multihash.js'
 import invalid from './fixtures/invalid-multihash.js'
+import { sha1 as chSha1 } from 'crypto-hash'
 import { hash as slSha256 } from '@stablelib/sha256'
 import { hash as slSha512 } from '@stablelib/sha512'
 import { assert } from 'aegir/chai'
@@ -39,6 +41,32 @@ describe('multihash', () => {
       }
     })
 
+    it('hash sha1', async () => {
+      const hash = await sha1.digest(fromString('test'))
+      assert.deepStrictEqual(hash.code, sha1.code)
+      assert.deepStrictEqual(hash.digest, fromHex(await chSha1(fromString('test'))))
+
+      const hash2 = decodeDigest(hash.bytes)
+      assert.deepStrictEqual(hash2.code, sha1.code)
+      assert.deepStrictEqual(hash2.bytes, hash.bytes)
+    })
+
+    if (typeof navigator === 'undefined') {
+      it('sync sha1', async () => {
+        const hash = sha1.digest(fromString('test'))
+        if (hash instanceof Promise) {
+          assert.fail('expected sync result')
+        } else {
+          assert.deepStrictEqual(hash.code, sha1.code)
+          assert.deepStrictEqual(hash.digest, fromHex(await chSha1(fromString('test'))))
+
+          const hash2 = decodeDigest(hash.bytes)
+          assert.deepStrictEqual(hash2.code, sha1.code)
+          assert.deepStrictEqual(hash2.bytes, hash.bytes)
+        }
+      })
+    }
+
     it('hash sha2-256', async () => {
       const hash = await sha256.digest(fromString('test'))
       assert.deepStrictEqual(hash.code, sha256.code)