Breaking: Replace deprecated / archived crypto library (#80)

README.md

@@ -36,7 +36,7 @@ As `ots` is designed to never let the server know the secret you are sharing you
 This is slightly more complex as you first need to encrypt your secret before sending it to the API but in this case you can be sure the server will in no case be able to access the secret. Especially if you are using ots.fyi (my public hosted instance) you should not trust me with your secret but use an encrypted secret:
 
 ```console
-# echo "my password" | openssl aes-256-cbc -base64 -pass pass:mypass -md md5
+# echo "my password" | openssl aes-256-cbc -base64 -pass pass:mypass -iter 300000 -md sha512
 U2FsdGVkX18wJtHr6YpTe8QrvMUUdaLZ+JMBNi1OvOQ=
 
 # curl -X POST -H 'content-type: application/json' -i -s -d '{"secret": "U2FsdGVkX18wJtHr6YpTe8QrvMUUdaLZ+JMBNi1OvOQ="}' https://ots.fyi/api/create

cli_create.sh

@@ -1,6 +1,8 @@
 #!/bin/bash
 set -euo pipefail
 
+: ${INSTANCE:=https://ots.fyi} # Where to reach the API of the instance (omit trailing slash)
+
 deps=(curl jq)
 for cmd in "${deps[@]}"; do
   which ${cmd} >/dev/null || {
@@ -16,11 +18,11 @@ SECRET=${1:-}
   exit 1
 }
 
-# Generate a random 8 character password
-pass=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | head -c 8 || true)
+# Generate a random 20 character password
+pass=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | head -c 20 || true)
 
 # Encrypt the secret
-ciphertext=$(echo "${SECRET}" | openssl aes-256-cbc -base64 -pass "pass:${pass}" -md md5 2>/dev/null)
+ciphertext=$(echo "${SECRET}" | openssl aes-256-cbc -base64 -pass "pass:${pass}" -iter 300000 -md sha512 2>/dev/null)
 
 # Create a secret and extract the secret ID
 id=$(
@@ -28,9 +30,9 @@ id=$(
     -X POST \
     -H 'content-type: application/json' \
     -d "$(jq --arg secret "${ciphertext}" -cn '{"secret": $secret}')" \
-		https://ots.fyi/api/create |
+    "${INSTANCE}/api/create" |
     jq -r '.secret_id'
 )
 
 # Display URL to user
-echo -e "Secret is now available at:\nhttps://ots.fyi/#${id}%7C${pass}"
+echo -e "Secret is now available at:\n${INSTANCE}/#${id}%7C${pass}"

cli_get.sh

@@ -25,4 +25,4 @@ geturl="${host}/api/get/${id}"
 
 # fetch secret and decrypt to STDOUT
 curl -sSf "${geturl}" | jq -r ".secret" |
-	openssl aes-256-cbc -base64 -pass "pass:${pass}" -md md5 -d 2>/dev/null
+  openssl aes-256-cbc -base64 -pass "pass:${pass}" -iter 300000 -md sha512 -d 2>/dev/null

src/app.vue

@@ -166,7 +166,7 @@
 
 <script>
 import axios from 'axios'
-import AES from 'gibberish-aes/src/gibberish-aes'
+import crypto from './crypto.js'
 
 const passwordCharset = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
 const passwordLength = 20
@@ -218,9 +218,8 @@ export default {
       this.securePassword = [...window.crypto.getRandomValues(new Uint8Array(passwordLength))]
         .map(n => passwordCharset[n % passwordCharset.length])
         .join('')
-      const secret = AES.enc(this.secret, this.securePassword)
-
-      axios.post('api/create', { secret })
+      crypto.enc(this.secret, this.securePassword)
+        .then(secret => axios.post('api/create', { secret })
           .then(resp => {
             this.secretId = resp.data.secret_id
             this.secret = ''
@@ -238,7 +237,7 @@ export default {
               this.error = this.$t('alert-something-went-wrong')
               this.showError = true
             }
-        })
+          }))
 
       return false
     },
@@ -267,11 +266,20 @@ export default {
     requestSecret() {
       axios.get(`api/get/${this.secretId}`)
         .then(resp => {
-          let secret = resp.data.secret
-          if (this.securePassword) {
-            secret = AES.dec(secret, this.securePassword)
-          }
+          const secret = resp.data.secret
+          if (!this.securePassword) {
             this.secret = secret
+            return
+          }
+
+          crypto.dec(secret, this.securePassword)
+            .then(secret => {
+              this.secret = secret
+            })
+            .catch(() => {
+              this.error = this.$t('alert-something-went-wrong')
+              this.showError = true
+            })
         })
         .catch(err => {
           switch (err.response.status) {

src/crypto.js

@@ -0,0 +1,35 @@
+const opensslBanner = new Uint8Array(new TextEncoder('utf8').encode('Salted__'))
+const pbkdf2Params = { hash: 'SHA-512', iterations: 300000, name: 'PBKDF2' }
+
+function decrypt(passphrase, encData) {
+  const data = new Uint8Array(atob(encData).split('')
+    .map(c => c.charCodeAt(0)))
+
+  return deriveKey(passphrase, data.slice(8, 16))
+    .then(({ iv, key }) => window.crypto.subtle.decrypt({ iv, name: 'AES-CBC' }, key, data.slice(16)))
+    .then(data => new TextDecoder('utf8').decode(data))
+}
+
+function deriveKey(passphrase, salt) {
+  return window.crypto.subtle.importKey('raw', new TextEncoder('utf8').encode(passphrase), 'PBKDF2', false, ['deriveBits'])
+    .then(passwordKey => window.crypto.subtle.deriveBits({ ...pbkdf2Params, salt }, passwordKey, 384))
+    .then(key => window.crypto.subtle.importKey('raw', key.slice(0, 32), { name: 'AES-CBC' }, false, ['encrypt', 'decrypt'])
+      .then(aesKey => ({ iv: key.slice(32, 48), key: aesKey })))
+}
+
+function encrypt(passphrase, salt, plainData) {
+  return deriveKey(passphrase, salt)
+    .then(({ iv, key }) => window.crypto.subtle.encrypt({ iv, name: 'AES-CBC' }, key, new TextEncoder('utf8').encode(plainData)))
+    .then(encData => new Uint8Array([...opensslBanner, ...salt, ...new Uint8Array(encData)]))
+    .then(data => btoa(String.fromCharCode.apply(null, data)))
+}
+
+function generateSalt() {
+  const salt = new Uint8Array(8) // Salt MUST consist of 8 byte
+  return window.crypto.getRandomValues(salt)
+}
+
+export default {
+  dec: (cipherText, passphrase) => decrypt(passphrase, cipherText),
+  enc: (plainText, passphrase) => encrypt(passphrase, generateSalt(), plainText),
+}

src/package-lock.json

@@ -10,7 +10,6 @@
         "bootstrap": "^4.6.0",
         "bootstrap-vue": "^2.21.2",
         "bootswatch": "^4.6.0",
-        "gibberish-aes": "^1.0.0",
         "popper.js": "^1.16.1",
         "vue": "^2.6.14",
         "vue-i18n": "^8.25.0"
@@ -3907,11 +3906,6 @@
         "assert-plus": "^1.0.0"
       }
     },
-    "node_modules/gibberish-aes": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/gibberish-aes/-/gibberish-aes-1.0.0.tgz",
-      "integrity": "sha1-9kHEWPuCLgrWHDwN6hWOC5Q+n8U="
-    },
     "node_modules/glob": {
       "version": "7.1.7",
       "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.7.tgz",

src/package.json

@@ -27,7 +27,6 @@
     "bootstrap": "^4.6.0",
     "bootstrap-vue": "^2.21.2",
     "bootswatch": "^4.6.0",
-    "gibberish-aes": "^1.0.0",
     "popper.js": "^1.16.1",
     "vue": "^2.6.14",
     "vue-i18n": "^8.25.0"