forgejo/models/ssh_key_fingerprint.go
wxiaoguang 750a8465f5
A better go code formatter, and now make fmt can run in Windows (#17684)
* go build / format tools
* re-format imports
2021-11-17 20:34:35 +08:00

99 lines
3 KiB
Go

// Copyright 2021 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package models
import (
"errors"
"fmt"
"strings"
"code.gitea.io/gitea/models/db"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/process"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/util"
"golang.org/x/crypto/ssh"
)
// ___________.__ .__ __
// \_ _____/|__| ____ ____ ________________________|__| _____/ |_
// | __) | |/ \ / ___\_/ __ \_ __ \____ \_ __ \ |/ \ __\
// | \ | | | \/ /_/ > ___/| | \/ |_> > | \/ | | \ |
// \___ / |__|___| /\___ / \___ >__| | __/|__| |__|___| /__|
// \/ \//_____/ \/ |__| \/
//
// This file contains functions for fingerprinting SSH keys
//
// The database is used in checkKeyFingerprint however most of these functions probably belong in a module
// checkKeyFingerprint only checks if key fingerprint has been used as public key,
// it is OK to use same key as deploy key for multiple repositories/users.
func checkKeyFingerprint(e db.Engine, fingerprint string) error {
has, err := e.Get(&PublicKey{
Fingerprint: fingerprint,
})
if err != nil {
return err
} else if has {
return ErrKeyAlreadyExist{0, fingerprint, ""}
}
return nil
}
func calcFingerprintSSHKeygen(publicKeyContent string) (string, error) {
// Calculate fingerprint.
tmpPath, err := writeTmpKeyFile(publicKeyContent)
if err != nil {
return "", err
}
defer func() {
if err := util.Remove(tmpPath); err != nil {
log.Warn("Unable to remove temporary key file: %s: Error: %v", tmpPath, err)
}
}()
stdout, stderr, err := process.GetManager().Exec("AddPublicKey", "ssh-keygen", "-lf", tmpPath)
if err != nil {
if strings.Contains(stderr, "is not a public key file") {
return "", ErrKeyUnableVerify{stderr}
}
return "", fmt.Errorf("'ssh-keygen -lf %s' failed with error '%s': %s", tmpPath, err, stderr)
} else if len(stdout) < 2 {
return "", errors.New("not enough output for calculating fingerprint: " + stdout)
}
return strings.Split(stdout, " ")[1], nil
}
func calcFingerprintNative(publicKeyContent string) (string, error) {
// Calculate fingerprint.
pk, _, _, _, err := ssh.ParseAuthorizedKey([]byte(publicKeyContent))
if err != nil {
return "", err
}
return ssh.FingerprintSHA256(pk), nil
}
func calcFingerprint(publicKeyContent string) (string, error) {
// Call the method based on configuration
var (
fnName, fp string
err error
)
if setting.SSH.StartBuiltinServer {
fnName = "calcFingerprintNative"
fp, err = calcFingerprintNative(publicKeyContent)
} else {
fnName = "calcFingerprintSSHKeygen"
fp, err = calcFingerprintSSHKeygen(publicKeyContent)
}
if err != nil {
if IsErrKeyUnableVerify(err) {
log.Info("%s", publicKeyContent)
return "", err
}
return "", fmt.Errorf("%s: %v", fnName, err)
}
return fp, nil
}