diff --git a/plumbing/transport/ssh/auth_method.go b/plumbing/transport/ssh/auth_method.go index 9d3bcd359..e89ce4ba3 100644 --- a/plumbing/transport/ssh/auth_method.go +++ b/plumbing/transport/ssh/auth_method.go @@ -43,6 +43,7 @@ const ( type KeyboardInteractive struct { User string Challenge ssh.KeyboardInteractiveChallenge + HostKeyCallbackHelper } func (a *KeyboardInteractive) Name() string { @@ -54,18 +55,19 @@ func (a *KeyboardInteractive) String() string { } func (a *KeyboardInteractive) ClientConfig() (*ssh.ClientConfig, error) { - return &ssh.ClientConfig{ + return a.SetHostKeyCallback(&ssh.ClientConfig{ User: a.User, Auth: []ssh.AuthMethod{ a.Challenge, }, - }, nil + }) } // Password implements AuthMethod by using the given password. type Password struct { User string Password string + HostKeyCallbackHelper } func (a *Password) Name() string { @@ -77,10 +79,10 @@ func (a *Password) String() string { } func (a *Password) ClientConfig() (*ssh.ClientConfig, error) { - return &ssh.ClientConfig{ + return a.SetHostKeyCallback(&ssh.ClientConfig{ User: a.User, Auth: []ssh.AuthMethod{ssh.Password(a.Password)}, - }, nil + }) } // PasswordCallback implements AuthMethod by using a callback @@ -88,6 +90,7 @@ func (a *Password) ClientConfig() (*ssh.ClientConfig, error) { type PasswordCallback struct { User string Callback func() (pass string, err error) + HostKeyCallbackHelper } func (a *PasswordCallback) Name() string { @@ -99,16 +102,17 @@ func (a *PasswordCallback) String() string { } func (a *PasswordCallback) ClientConfig() (*ssh.ClientConfig, error) { - return &ssh.ClientConfig{ + return a.SetHostKeyCallback(&ssh.ClientConfig{ User: a.User, Auth: []ssh.AuthMethod{ssh.PasswordCallback(a.Callback)}, - }, nil + }) } // PublicKeys implements AuthMethod by using the given key pairs. type PublicKeys struct { User string Signer ssh.Signer + HostKeyCallbackHelper } // NewPublicKeys returns a PublicKeys from a PEM encoded private key. An @@ -147,10 +151,10 @@ func (a *PublicKeys) String() string { } func (a *PublicKeys) ClientConfig() (*ssh.ClientConfig, error) { - return &ssh.ClientConfig{ + return a.SetHostKeyCallback(&ssh.ClientConfig{ User: a.User, Auth: []ssh.AuthMethod{ssh.PublicKeys(a.Signer)}, - }, nil + }) } func username() (string, error) { @@ -173,6 +177,7 @@ func username() (string, error) { type PublicKeysCallback struct { User string Callback func() (signers []ssh.Signer, err error) + HostKeyCallbackHelper } // NewSSHAgentAuth returns a PublicKeysCallback based on a SSH agent, it opens @@ -207,10 +212,10 @@ func (a *PublicKeysCallback) String() string { } func (a *PublicKeysCallback) ClientConfig() (*ssh.ClientConfig, error) { - return &ssh.ClientConfig{ + return a.SetHostKeyCallback(&ssh.ClientConfig{ User: a.User, Auth: []ssh.AuthMethod{ssh.PublicKeysCallback(a.Callback)}, - }, nil + }) } // NewKnownHostsCallback returns ssh.HostKeyCallback based on a file based on a @@ -286,9 +291,6 @@ func filterKnownHostsFiles(files ...string) ([]string, error) { // HostKeyCallbackHelper is a helper that provides common functionality to // configure HostKeyCallback into a ssh.ClientConfig. -// Deprecated in favor of SetConfigHostKeyFields (see common.go) which provides -// a mechanism for also setting ClientConfig.HostKeyAlgorithms for a specific -// host. type HostKeyCallbackHelper struct { // HostKeyCallback is the function type used for verifying server keys. // If nil default callback will be create using NewKnownHostsCallback diff --git a/plumbing/transport/ssh/common.go b/plumbing/transport/ssh/common.go index 4b9ac0797..1407a7dc7 100644 --- a/plumbing/transport/ssh/common.go +++ b/plumbing/transport/ssh/common.go @@ -10,6 +10,7 @@ import ( "github.com/go-git/go-git/v5/plumbing/transport" "github.com/go-git/go-git/v5/plumbing/transport/internal/common" + "github.com/skeema/knownhosts" "github.com/kevinburke/ssh_config" "golang.org/x/crypto/ssh" @@ -122,9 +123,11 @@ func (c *command) connect() error { return err } hostWithPort := c.getHostWithPort() - config, err = SetConfigHostKeyFields(config, hostWithPort) - if err != nil { - return err + if config.HostKeyCallback != nil { + // Set the HostKeyAlgorithms based on HostKeyCallback. + // For background see https://github.com/go-git/go-git/issues/411 as well as + // https://github.com/golang/go/issues/29286 for root cause. + config.HostKeyAlgorithms = knownhosts.HostKeyAlgorithms(config.HostKeyCallback, hostWithPort) } overrideConfig(c.config, config) @@ -167,23 +170,6 @@ func dial(network, addr string, config *ssh.ClientConfig) (*ssh.Client, error) { return ssh.NewClient(c, chans, reqs), nil } -// SetConfigHostKeyFields sets cfg.HostKeyCallback and cfg.HostKeyAlgorithms -// based on OpenSSH known_hosts. cfg is modified in-place. hostWithPort must be -// supplied, since the algorithms will be set based on the known host keys for -// that specific host. Otherwise, golang.org/x/crypto/ssh can return an error -// upon connecting to a host whose *first* key is not known, even though other -// keys (of different types) are known and match properly. -// For background see https://github.com/go-git/go-git/issues/411 as well as -// https://github.com/golang/go/issues/29286 for root cause. -func SetConfigHostKeyFields(cfg *ssh.ClientConfig, hostWithPort string) (*ssh.ClientConfig, error) { - kh, err := newKnownHosts() - if err == nil { - cfg.HostKeyCallback = kh.HostKeyCallback() - cfg.HostKeyAlgorithms = kh.HostKeyAlgorithms(hostWithPort) - } - return cfg, err -} - func (c *command) getHostWithPort() string { if addr, found := c.doGetHostWithPortFromSSHConfig(); found { return addr