pgp_keyfinder.go

// Copyright 2015 Keybase, Inc. All rights reserved. Use of
// this source code is governed by the included BSD license.

package engine

import (
	"fmt"

	"github.com/keybase/client/go/libkb"
	keybase1 "github.com/keybase/client/go/protocol"
)

// PGPKeyfinder is an engine to find PGP Keys for users (loaded by
// assertions), possibly tracking them if necessary.
type PGPKeyfinder struct {
	arg      *PGPKeyfinderArg
	uplus    []*UserPlusKeys
	loggedIn bool
	me       *libkb.User
	runerr   error
	libkb.Contextified
}

type PGPKeyfinderArg struct {
	Users        []string
	SkipTrack    bool
	TrackOptions keybase1.TrackOptions
}

// NewPGPKeyfinder creates a PGPKeyfinder engine.
func NewPGPKeyfinder(arg *PGPKeyfinderArg, g *libkb.GlobalContext) *PGPKeyfinder {
	return &PGPKeyfinder{
		arg:          arg,
		Contextified: libkb.NewContextified(g),
	}
}

// Name is the unique engine name.
func (e *PGPKeyfinder) Name() string {
	return "PGPKeyfinder"
}

// GetPrereqs returns the engine prereqs.
func (e *PGPKeyfinder) Prereqs() Prereqs {
	return Prereqs{}
}

// RequiredUIs returns the required UIs.
func (e *PGPKeyfinder) RequiredUIs() []libkb.UIKind {
	return []libkb.UIKind{}
}

// SubConsumers returns the other UI consumers for this engine.
func (e *PGPKeyfinder) SubConsumers() []libkb.UIConsumer {
	return []libkb.UIConsumer{
		&TrackEngine{},
		&Identify{},
	}
}

// Run starts the engine.
func (e *PGPKeyfinder) Run(ctx *Context) error {
	e.setup(ctx)
	e.verifyUsers(ctx)
	e.loadKeys(ctx)
	return e.runerr
}

// UsersPlusKeys returns the users found while running the engine,
// plus their pgp keys.
func (e *PGPKeyfinder) UsersPlusKeys() []*UserPlusKeys {
	return e.uplus
}

func (e *PGPKeyfinder) setup(ctx *Context) {
	if e.runerr != nil {
		return
	}

	ok, err := IsLoggedIn(e, ctx)
	if err != nil {
		e.runerr = err
		return
	}
	e.loggedIn = ok
}

func (e *PGPKeyfinder) verifyUsers(ctx *Context) {
	if e.runerr != nil {
		return
	}

	if e.loggedIn && !e.arg.SkipTrack {
		e.loadMe()
		e.trackUsers(ctx)
	} else {
		e.identifyUsers(ctx)
	}
}

func (e *PGPKeyfinder) trackUsers(ctx *Context) {
	if e.runerr != nil {
		return
	}

	// need to track any users we aren't tracking
	for _, u := range e.arg.Users {
		if err := e.trackUser(ctx, u); err != nil {
			// ignore self track errors
			if _, ok := err.(libkb.SelfTrackError); !ok {
				e.runerr = err
				return
			}
		}
	}
}

func (e *PGPKeyfinder) identifyUsers(ctx *Context) {
	if e.runerr != nil {
		return
	}

	// need to identify all the users
	for _, u := range e.arg.Users {
		if err := e.identifyUser(ctx, u); err != nil {
			e.runerr = err
			return
		}
	}
}

func (e *PGPKeyfinder) loadKeys(ctx *Context) {
	if e.runerr != nil {
		return
	}

	// get the pgp keys for all the users
	for _, x := range e.uplus {
		keys := x.User.GetActivePGPKeys(true)
		if len(keys) == 0 {
			e.runerr = fmt.Errorf("User %s doesn't have a pgp key", x.User.GetName())
			return
		}
		x.Keys = keys
	}
}

func (e *PGPKeyfinder) trackUser(ctx *Context, username string) error {
	e.G().Log.Debug("tracking user %q", username)
	arg := &TrackEngineArg{
		Me:            e.me,
		UserAssertion: username,
		Options:       e.arg.TrackOptions,
	}
	eng := NewTrackEngine(arg, e.G())
	if err := RunEngine(eng, ctx); err != nil {
		return err
	}
	e.addUser(eng.User(), true)
	return nil
}

// PC: maybe we need to bring the TrackUI back for the
// context...so that this one can use an IdentifyUI and trackUser
// can use a TrackUI...
func (e *PGPKeyfinder) identifyUser(ctx *Context, user string) error {
	arg := NewIdentifyArg(user, false, false)
	eng := NewIdentify(arg, e.G())
	if err := RunEngine(eng, ctx); err != nil {
		return err
	}
	e.addUser(eng.User(), false)
	return nil
}

type UserPlusKeys struct {
	User      *libkb.User
	IsTracked bool
	Keys      []*libkb.PGPKeyBundle
}

func (e *PGPKeyfinder) loadMe() {
	if e.runerr != nil {
		return
	}
	if e.me != nil {
		return
	}
	me, err := libkb.LoadMe(libkb.NewLoadUserArg(e.G()))
	if err != nil {
		e.runerr = err
		return
	}
	e.me = me
}

func (e *PGPKeyfinder) addUser(user *libkb.User, tracked bool) {
	e.uplus = append(e.uplus, &UserPlusKeys{User: user, IsTracked: tracked})
}