↳ Configuration file

A .json file including required configuration details must be provided using the -configfile command-line property when starting Tessera.

Many configuration options can be overridden using the command-line. See the Using CLI to override config page for more information.

↳ Configuration options

The configuration options are explained in more detail in this section. Configuration options that require more than a brief explanation are covered in separate pages.

↳ Cryptographic Keys

See Keys page.

↳ Whitelist

If set to true, the peers list will be used as the whitelisted urls for the Tessera node:

"useWhiteList": true,

↳ Database

Tessera's database uses JDBC to connect to an external database. Any valid JDBC URL may be specified, refer to your providers details to construct a valid JDBC URL.

"jdbc": {
  "url": "[JDBC URL]",
  "username": "[JDBC Username]",
  "password": "[JDBC Password]"
}

↳ Obfuscate database password in config file

Certain entries in the Tessera config file must be obfuscated in order to prevent any attempts from attackers to gain access to critical parts of the application (e.g. database). The database password can be encrypted using Jasypt to avoid it being exposed as plain text in the configuration file.

To enable this feature, simply replace your plain-text database password with its encrypted value and wrap it inside an ENC() function.

"jdbc": {
    "username": "sa",
    "password": "ENC(ujMeokIQ9UFHSuBYetfRjQTpZASgaua3)",
    "url": "jdbc:h2:/qdata/c1/db1",
    "autoCreateTables": true
}

Being a Password-Based Encryptor, Jasypt requires a secret key (password) and a configured algorithm to encrypt/decrypt this config entry. This password can either be loaded into Tessera from file system or user input. For file system input, the location of this secret file needs to be set in Environment Variable TESSERA_CONFIG_SECRET

If the database password is not wrapped inside ENC(), Tessera will simply treat it as a plain-text password however this approach is not recommended for production environments.

!!! note
Jasypt encryption is currently only available for the jdbc.password field

↳ How to encrypt database password

1. Download and unzip Jasypt and redirect to the bin directory
2. Encrypt the password

   $ ./encrypt.sh input=dbpassword password=Smilo
   ----ENVIRONMENT-----------------
   Runtime: Oracle Corporation Java HotSpot(TM) 64-Bit Server VM 25.171-b11 
   ----ARGUMENTS-------------------
   input: dbpassword
   password: Smilo
   ----OUTPUT----------------------
   rJ70hNidkrpkTwHoVn2sGSp3h3uBWxjb
   

3. Place the wrapped output, ENC(rJ70hNidkrpkTwHoVn2sGSp3h3uBWxjb), in the config json file

↳ Server

For Tessera versions prior to 0.8: See Legacy Server Settings.

To allow for a greater level of control, Tessera's API has been separated into distinct groups. Each group is only accessible over a specific server type. Tessera can be started with different combinations of these servers depending on the functionality required. This is defined in the configuration and determines the APIs that are available and how they are accessed.

The possible server types are:

• P2P - Tessera uses this server to communicate with other Transaction Managers (the URI for this server can be shared with other nodes to be used in their peer list - see below)
• Q2T - This server is used for communications between Tessera and its corresponding Smilo node
• ENCLAVE - If using a remote enclave, this defines the connection details for the remote enclave server (see the Enclave docs for more info)
• ThirdParty - This server is used to expose certain Transaction Manager functionality to external services such as Smilo.js

The servers to be started are provided as a list:

"serverConfigs": [
   ...<server settings>...
]

Each server is individually configurable and can advertise over HTTP, HTTPS or a Unix Socket. The format of an individual server config is slightly different between Tessera v0.9 and v0.8:

↳ Server configuration (v0.9)

HTTP:

{
    "app": "<app type>",
    "enabled": <boolean>,
    "serverAddress":"http://[host]:[port]/[path]
    "communicationType" : <enum>, // "REST" or "GRPC"
}

HTTPS:

{
    "app": "<app type>",
    "enabled": <boolean>,
    "serverAddress":"https://[host]:[port]/[path]
    "communicationType" : <enum>, // "REST" or "GRPC"
    "sslConfig": {
        ...<SSL settings, see below>...
    }
}

Unix Socket:

{
    "app": "<app type>",
    "enabled": <boolean>,
    "serverAddress":"unix://[path],
    "communicationType" : "REST"
}

↳ Server configuration (v0.8)

HTTP:

{
    "app": "<app type>",
    "enabled": <boolean>,
    "serverSocket":{
        "type": "INET",
        "port": <int>, //The port to advertise and bind on (if binding address not set)
        "hostName": <string> // The hostname to advertise and bind on (if binding address not set)
    },
    "communicationType" : <enum>, // "REST" or "GRPC"
    "bindingAddress": <string> //An address to bind the server to that overrides the one defined above
}

HTTPS:

{
    "app": "<app type>",
    "enabled": <boolean>,
    "serverSocket":{
        "type": "INET",
        "port": <int>, //The port to advertise and bind on (if binding address not set)
        "hostName": <string> // The hostname to advertise and bind on (if binding address not set)
    },
    "communicationType" : <enum>, // "REST" or "GRPC"
    "bindingAddress": <string>, //An address to bind the server to that overrides the one defined above
    "sslConfig": {
       ...<SSL settings, see below>...
    }
}

Unix Socket:

{
    "app": "<app type>",  
    "enabled": <boolean>, 
    "serverSocket":{
        "type":"UNIX",
        "path": <string> //the path of the unix socket to create
    },
    "communicationType" : "UNIX_SOCKET"
}

↳ TLS/SSL: server sub-config

See TLS/SSL page.

↳ CORS: server sub-config

For the ThirdParty server type it may be relevant to configure CORS.

{
    "app":"ThirdParty",
    "enabled": true,
    "serverAddress": "http://localhost:9081",
    "communicationType" : "REST",
    "cors" : {
        "allowedMethods" : ["GET", "POST", "PUT", "DELETE", "OPTIONS", "HEAD"],
        "allowedOrigins" : ["http://localhost:63342"],
        "allowedHeaders" : ["content-type"],
        "allowCredentials" : true
    }
},

The configurable fields are:

• allowedMethods - the list of allowed HTTP methods. If omitted the default list containing "GET", "POST", "PUT", "DELETE", "OPTIONS", "HEAD" is used.
• allowedOrigins - the list of domains from which to accept cross origin requests (browser enforced). Each entry in the list can contain the "*" (wildcard) character which matches any sequence of characters. Ex: "*locahost" would match "http://localhost" or "https://localhost". There is no default for this field.
• allowedHeaders - the list of allowed headers. If omitted the request Access-Control-Request-Headers are copied into the response as Access-Control-Allow-Headers.
• allowCredentials - the value for the Access-Control-Allow-Credentials response header. If omitted the default true value would be used.

↳ InfluxDB Config: server sub-config

Configuration details to allow Tessera to record monitoring data to a running InfluxDB instance.

"influxConfig": {
  "hostName": "[Hostname of Influx instance]",
  "port": "[Port of Influx instance]",
  "pushIntervalInSecs": "[How often to push data to InfluxDB]",
  "dbName": "[Name of InfluxDB]"
}

↳ Peers

A list of URLs used by Tessera to communicate with other nodes. Peer info is shared between nodes during runtime (however, please note the section on Peer Discovery below).

"peer": [
  {
    "url": "http://myhost.com:9000"
  },
  {
    "url": "http://myhost.com:9001"
  },
  {
    "url": "http://myhost.com:9002"
  }
]

↳ Disabling peer discovery

If peer discovery is disabled, then only peers defined in the configuration file will be communicated with; any peers notified by other nodes will be ignored. This allows nodes to be 'locked down' if desired.

"disablePeerDiscovery": true

↳ Always-send-to

It is possible to configure a node that will be sent a copy of every transaction, even if it is not specified as a party to the transaction. This could be used, for example, to send a copy of every transaction to a node for audit purposes. Specify the public keys to forward transactions onto, and these will be included as if you had specified them on the privateFor field to start with.

"alwaysSendTo":["<public key 1>", "<public key 2>"]

↳ Remote-Key-Validation

Tessera provides an API /partyinfo on Tessera P2P server to discover all the peers in the network. In order to prevent attackers trying to inject malicious addresses against public keys, where they will try to assign the address to direct private transactions to them instead of the real owner of the key, we have added a feature to enable node level validation on the remote key that checks the remote node does in fact own the keys that were advertised. Only after the keys are validated with the remote node to ensure they own them, the keys are added to the local network info (partyinfo) store.

Default configuration for this is false as this is BREAKABLE change to lower versions to Tessera 0.10.0. To enable this, simple set below parameter to true in the configuration:

 "features": {
    "enableRemoteKeyValidation": true
  }

↳ Alternative cryptographic elliptic curves

By default Tessera's Enclave uses the jnacl implementation of the NaCl library to encrypt/decrypt private payloads.

NaCl provides public-key authenticated encryption by using curve25519xsalsa20poly1305, a combination of the:

1. Curve25519 Diffie-Hellman key-exchange function: based on fast arithmetic on a strong elliptic curve
2. Salsa20 stream cipher: encrypts a message using the shared secret
3. Poly1305 message-authentication code: authenticates the encrypted message using a shared secret

The NaCl primitives provide good security and speed and should be sufficient in most circumstances.

However, the Enclave also supports the JCA (Java Cryptography Architecture) framework. Supplying a compatible JCA provider (e.g. SunEC provider) and the necessary Tessera config allows the NaCl primitives to be replaced with alternative curves and symmetric ciphers.

The same Enclave encryption process as described in Lifecycle of a private transaction is used regardless of whether the NaCl or JCA Encryptor are configured.

This is a feature introduced in Tessera v0.10.2. Providing no encryptor configuration means the default NaCl encryptor is used.

"encryptor": {
    "type":"EC",
    "properties":{
        "symmetricCipher":"AES/GCM/NoPadding",
        "ellipticCurve":"secp256r1",
        "nonceLength":"24",
        "sharedKeyLength":"32"
    }
}

If type is set to EC, the following properties fields can also be configured: