Authenticated HTTP API - first pass

api_auth_docker/README.md

@@ -0,0 +1,120 @@
+# HTTP/S API supporting HMAC API keys
+
+So all the other containers are in the Docker Swarm and we want to expose a real HTTP/S interface to clients outside of the Swarm, that makes sense.  Clients have to get an API key first.
+
+## API key
+
+Let's produce a 256-bits key that we'll convert in an hex string to store and use with openssl hmac feature.
+
+```shell
+dd if=/dev/urandom bs=32 count=1 2> /dev/null | xxd -pc 32
+```
+
+The key is stored in keys.properties and must be given to the client.  This is a secret key.  keys.properties looks like this:
+
+```property
+#keyid=hex(key)
+key001=2df1eeea370eacdc5cf7e96c2d82140d1568079a5d4d87006ec8718a98883b36
+key002=50c5e483b80964595508f214229b014aa6c013594d57d38bcb841093a39f1d83
+```
+
+### Bearer token
+
+Following JWT (JSON Web Tokens) standard, we build a bearer token that will be in the request header and signed with the secret key.  We need this in the request header:
+
+```shell
+Authorization: Bearer <token>
+```
+
+...where token is:
+
+```shell
+token = hhh.ppp.sss
+```
+
+...where hhh is the header in base64, ppp is the payload in base64 and sss is the signature.  Here are the expected formats and contents:
+
+```shell
+header = {"alg":"HS256","typ":"JWT"}
+header64 = base64(header) = eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9Cg==
+```
+
+```shell
+payload = {"id":"001","exp":1538528077}
+payload64 = base64(payload) = eyJpZCI6IjAwMSIsImV4cCI6MTUzODUyODA3N30K
+```
+
+The "id" property is the client id and the "exp" property should be current epoch time + 10 seconds, like:
+
+```shell
+$((`date +"%s"`+10))
+```
+
+...so that the request will be expired in 10 seconds.  That should take care of most Replay attacks if any.  You should run nginx with TLS so that the replay attack can't be possible.
+
+```shell
+signature = hmacsha256(header64.payload64, key)
+```
+
+```shell
+token = header64 + "." + payload64 + "." + signature
+```
+
+### cURL example of an API invocation
+
+Instruction should be in the form:
+
+```shell
+curl -v -H "Authorization: Bearer hhh.ppp.sss" localhost
+```
+
+10 seconds request expiration:
+
+```shell
+id="001";h64=$(echo "{\"alg\":\"HS256\",\"typ\":\"JWT\"}" | base64);p64=$(echo "{\"id\":\"$id\",\"exp\":$((`date +"%s"`+10))}" | base64);k="2df1eeea370eacdc5cf7e96c2d82140d1568079a5d4d87006ec8718a98883b36";s=$(echo "$h64.$p64" | openssl dgst -hmac "$k" -sha256 -r | cut -sd ' ' -f1);token="$h64.$p64.$s";curl -v -H "Authorization: Bearer $token" https://localhost/getbestblockhash
+```
+
+60 seconds request expiration:
+
+```shell
+id="001";h64=$(echo "{\"alg\":\"HS256\",\"typ\":\"JWT\"}" | base64);p64=$(echo "{\"id\":\"$id\",\"exp\":$((`date +"%s"`+60))}" | base64);k="2df1eeea370eacdc5cf7e96c2d82140d1568079a5d4d87006ec8718a98883b36";s=$(echo "$h64.$p64" | openssl dgst -hmac "$k" -sha256 -r | cut -sd ' ' -f1);token="$h64.$p64.$s";curl -v -H "Authorization: Bearer $token" https://localhost/getbestblockhash
+```
+
+## SSL
+
+Create your key and certificates.
+
+openssl req -subj '/CN=localhost' -x509 -newkey rsa:4096 -nodes -keyout ~/cyphernode/private/key.pem -out ~/cyphernode/certs/cert.pem -days 365
+
+Use default-ssl.conf as the template instead of default.conf.
+
+## Build
+
+### Create your API key and put it in keys.properties
+
+```shell
+dd if=/dev/urandom bs=32 count=1 2> /dev/null | xxd -pc 32
+```
+
+### Build and run docker image
+
+```shell
+docker build -t authapi .
+docker run -d --rm --name authapi -p 80:80 -p 443:443 --network cyphernodenet -v "~/cyphernode/certs:/etc/ssl/certs" -v "~/cyphernode/private:/etc/ssl/private" authapi
+```
+
+## Invoke cyphernode through authenticated API
+
+```shell
+id="001";h64=$(echo "{\"alg\":\"HS256\",\"typ\":\"JWT\"}" | base64);p64=$(echo "{\"id\":\"$id\",\"exp\":$((`date +"%s"`+10))}" | base64);k="2df1eeea370eacdc5cf7e96c2d82140d1568079a5d4d87006ec8718a98883b36";s=$(echo "$h64.$p64" | openssl dgst -hmac "$k" -sha256 -r | cut -sd ' ' -f1);token="$h64.$p64.$s";curl -v -H "Authorization: Bearer $token" https://localhost/getbestblockhash
+```
+
+## Technicalities
+
+```shell
+h64=$(echo "{\"alg\":\"HS256\",\"typ\":\"JWT\"}" | base64)
+p64=$(echo "{\"id\":\"001\",\"exp\":$((`date +"%s"`+10))}" | base64)
+k="2df1eeea370eacdc5cf7e96c2d82140d1568079a5d4d87006ec8718a98883b36"
+s=$(echo "$h64.$p64" | openssl dgst -hmac "$k" -sha256 -r | cut -sd ' ' -f1)
+token="$h64.$p64.$s"
+```