Team Operations

The sigchain protocol supports a variety of team operations. This section provides a brief overview of what these operations do. To learn about the way team invitations work, see Team Invitations.

enum Operation {
    Invite(Invitation),
    AcceptInvite(Identity),

    CloseInvitations(E),
    Leave(E),

    Promote(IdentityPublicKey),
    Demote(IdentityPublicKey),
    Remove(IdentityPublicKey),

    SetPolicy(Policy),
    SetTeamInfo(TeamInfo),
    PinHostKey(SSHHostKey),
    UnpinHostKey(SSHHostKey),
    AddLoggingEndpoint(LoggingEndpoint),
    RemoveLoggingEndpoint(LoggingEndpoint),
}

Close Invitations

A CloseInvitations operation invalidates all Invite operations that happened before it. If a prospective team member tries to post an AcceptInvite block that corresponds to a closed Invite, the AcceptInvite block will be rejected. When a DirectInvitation is used it is automatically closed, whereas IndirectInvitation’s remain open until explicitly closed. Only an admin can close all outstanding invitations.

Leave Team

Any member of the team can post a Leave block to remove themselves from the team. Doing so will prevent them from reading future blocks posted to the MainChain. Leaving a team does not prevent you from rejoining the team by accepting an appropriate Invite block if it is still open.

Manage Admins

As an admin, you can promote members to admin status and demote them from admin status by their public key.

Promote

When a Promote block is posted to the main chain by an admin, the member whose public key is specified will now be able to perform admin operations. The public key must belong to someone who is already on the team as a regular member.

Demote

When a Demote block is posted to the main chain by an admin, the admin whose public key is specified will no longer be able to perform admin operations. The public key must belong to someone who is an admin of the team. Being demoted does not prevent being promoted again in the future.

Remove Member

When an admin posts a Remove block to the main chain, two things happen:

1. The member whose public key is specified will be removed from the team
2. All outstanding invitations will be closed to prevent the removed member from rejoining using an indirect invitation.

Set Policy

The SetPolicy block allows an admin to change the auto-approval window for their team. The Policy included in a SetPolicy block looks like:

struct Policy {
    temporary_approval_seconds: Option<i64>,
}

Set Team Info

The SetTeamInfo block allows an admin to change the name of the team. The TeamInfo struct simply contains the new team name:

struct TeamInfo {
    name: String,
}

Host Public Key Pinning

Admins can pin and unpin host public keys by posting PinHostKey and UnpinHostKey blocks to the MainChain. These pinned host keys will be distributed to all members of the team and protect against man-in-the-middle attacks. To pin or unpin a host, an admin specifies the name of the host and a public key in the following struct:

struct SSHHostKey {
    host: String,
    public_key: Vec<u8>,
}

The same host can have many pinned public keys.

Logging

Finally, admins can add and remove logging endpoints with the AddLoggingEndpoint and RemoveLoggingEndpoint blocks. Adding a logging endpoint, such as the krypt.co team server, will export team members’ encrypted logs to the specified endpoint so that they can later be fetched, decrypted, and viewed by admins. Currently this amounts to enabling or disabling sending of encrypted logs to krypt.co’s sigchain server. Support for other endpoints may be added in the future.

To learn more about how logs are handled, read the logchain docs.