messasge signing

Messasge signing

Some of smart contracts can be invoked by any address. This is to support scenario, when a user wants to withdraw funds from pool to his wallet. For such operation to be accepted, it should have a valid signature issued by operator.

Construction of message signature

Every message is in fact a contract call performed by some user (i.e. UserA) represented by a principal (tx-sender) and having a list of uint arguments.

Operator, by signing the message should authorize both that UserA in fact is allowed to perform this request and that numeric parameters of the request have legal values.

Conceptually this is shown on diagram below.

                    arg1   arg2   arg3
                     \      |      /
                      \     |     /
                       \    |    /
                      +-----------+
                      |    join   |
                      +-----------+
                            |
                            v

                         argbuff
                            |
                            v
                          +----------+
 sender-pub-key-str -+--->|   join   |
                     |    +----------+
                     |         |
                     |         v
                     |    +----------+
                     |    |  sha256  |   operator-sec-key
                     |    +----------+           |
                     |         |                 +
                     |         v                /
                     |    +----------+         /
                     |    |   sign   |<-------+
                     |    +----------+
                     |         |
                     |         |
        Senderpubkey o         o operatorSignature

The latest version available here

(The content of the page is available for logged-in GitHub users)

Example

See makeSignature in admin.ts.