SmsRetriever hash generator

What is SmsRetriever

It is relatively new mechanism from Google that lets you handle SMS verification in your app without accessing SMSes directly. Just read here for more info.

Why SmsRetriever hash generator?

To use SmsRetriever you need hash that needs to be included in SMS sent from server. This hash is harder to generate than I thought:

• script provided in docs doesn't work for me (they get stuck and I don't want to fight with bash scripts)
• if you use Google Play signing, generating hash is not that obvious.

So I decided to wrap bash magic into Ruby script - for easier modification and easier usage.

Usage?

To run script from console: ruby google_play_sign.rb with parameters:

--package NAME               Your app package, e.g com.test.app
--google-play-key KEY_PATH   Google Play public key (in DER format) used to sign release app
--keystore KEYSTORE_PATH     Path to keystore (.jks file)
--keystore-password PASSWORD Password to the keystore - required only when option "--keystore" is specified
--key-alias KEY_ALIAS        Alias of key in the keystore - required only when option "--keystore" is specified
-h, --help                   Prints this help

So basically for generating hash from Google Play signing public key:

ruby google_play_sign.rb --package com.your.app --google-play-key deployment_key.der

and for generating hash from local keystore:

ruby google_play_sign.rb --package com.your.app --keystore keystore.jks --keystore-password mypassword --key-alias myalias

Credits

This Ruby script is based on bash script from https://github.com/googlesamples/android-credentials/blob/master/sms-verification/bin/sms_retriever_hash_v9.sh made by @ithinkihaveacat.