GoToSocial/internal/transport/controller.go

167 lines
5.9 KiB
Go

/*
GoToSocial
Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package transport
import (
"context"
"crypto"
"encoding/json"
"fmt"
"net/url"
"sync"
"github.com/go-fed/httpsig"
"github.com/spf13/viper"
"github.com/superseriousbusiness/activity/pub"
"github.com/superseriousbusiness/activity/streams"
"github.com/superseriousbusiness/gotosocial/internal/config"
"github.com/superseriousbusiness/gotosocial/internal/db"
"github.com/superseriousbusiness/gotosocial/internal/federation/federatingdb"
)
// Controller generates transports for use in making federation requests to other servers.
type Controller interface {
NewTransport(pubKeyID string, privkey crypto.PrivateKey) (Transport, error)
NewTransportForUsername(ctx context.Context, username string) (Transport, error)
}
type controller struct {
db db.DB
clock pub.Clock
client pub.HttpClient
appAgent string
// dereferenceFollowersShortcut is a shortcut to dereference followers of an
// account on this instance, without making any external api/http calls.
//
// It is passed to new transports, and should only be invoked when the iri.Host == this host.
dereferenceFollowersShortcut func(ctx context.Context, iri *url.URL) ([]byte, error)
// dereferenceUserShortcut is a shortcut to dereference followers an account on
// this instance, without making any external api/http calls.
//
// It is passed to new transports, and should only be invoked when the iri.Host == this host.
dereferenceUserShortcut func(ctx context.Context, iri *url.URL) ([]byte, error)
}
func dereferenceFollowersShortcut(federatingDB federatingdb.DB) func(context.Context, *url.URL) ([]byte, error) {
return func(ctx context.Context, iri *url.URL) ([]byte, error) {
followers, err := federatingDB.Followers(ctx, iri)
if err != nil {
return nil, err
}
i, err := streams.Serialize(followers)
if err != nil {
return nil, err
}
return json.Marshal(i)
}
}
func dereferenceUserShortcut(federatingDB federatingdb.DB) func(context.Context, *url.URL) ([]byte, error) {
return func(ctx context.Context, iri *url.URL) ([]byte, error) {
user, err := federatingDB.Get(ctx, iri)
if err != nil {
return nil, err
}
i, err := streams.Serialize(user)
if err != nil {
return nil, err
}
return json.Marshal(i)
}
}
// NewController returns an implementation of the Controller interface for creating new transports
func NewController(db db.DB, federatingDB federatingdb.DB, clock pub.Clock, client pub.HttpClient) Controller {
applicationName := viper.GetString(config.Keys.ApplicationName)
host := viper.GetString(config.Keys.Host)
appAgent := fmt.Sprintf("%s %s", applicationName, host)
return &controller{
db: db,
clock: clock,
client: client,
appAgent: appAgent,
dereferenceFollowersShortcut: dereferenceFollowersShortcut(federatingDB),
dereferenceUserShortcut: dereferenceUserShortcut(federatingDB),
}
}
// NewTransport returns a new http signature transport with the given public key id (a URL), and the given private key.
func (c *controller) NewTransport(pubKeyID string, privkey crypto.PrivateKey) (Transport, error) {
prefs := []httpsig.Algorithm{httpsig.RSA_SHA256}
digestAlgo := httpsig.DigestSha256
getHeaders := []string{httpsig.RequestTarget, "host", "date"}
postHeaders := []string{httpsig.RequestTarget, "host", "date", "digest"}
getSigner, _, err := httpsig.NewSigner(prefs, digestAlgo, getHeaders, httpsig.Signature, 120)
if err != nil {
return nil, fmt.Errorf("error creating get signer: %s", err)
}
postSigner, _, err := httpsig.NewSigner(prefs, digestAlgo, postHeaders, httpsig.Signature, 120)
if err != nil {
return nil, fmt.Errorf("error creating post signer: %s", err)
}
sigTransport := pub.NewHttpSigTransport(c.client, c.appAgent, c.clock, getSigner, postSigner, pubKeyID, privkey)
return &transport{
client: c.client,
appAgent: c.appAgent,
gofedAgent: "(go-fed/activity v1.0.0)",
clock: c.clock,
pubKeyID: pubKeyID,
privkey: privkey,
sigTransport: sigTransport,
getSigner: getSigner,
getSignerMu: &sync.Mutex{},
dereferenceFollowersShortcut: c.dereferenceFollowersShortcut,
dereferenceUserShortcut: c.dereferenceUserShortcut,
}, nil
}
func (c *controller) NewTransportForUsername(ctx context.Context, username string) (Transport, error) {
// We need an account to use to create a transport for dereferecing something.
// If a username has been given, we can fetch the account with that username and use it.
// Otherwise, we can take the instance account and use those credentials to make the request.
var u string
if username == "" {
u = viper.GetString(config.Keys.Host)
} else {
u = username
}
ourAccount, err := c.db.GetLocalAccountByUsername(ctx, u)
if err != nil {
return nil, fmt.Errorf("error getting account %s from db: %s", username, err)
}
transport, err := c.NewTransport(ourAccount.PublicKeyURI, ourAccount.PrivateKey)
if err != nil {
return nil, fmt.Errorf("error creating transport for user %s: %s", username, err)
}
return transport, nil
}