package client import ( "bytes" "crypto/tls" "encoding/json" "fmt" "io/ioutil" "net/http" "net/url" "path" "time" "github.com/nsheridan/cashier/lib" "golang.org/x/crypto/ssh" "golang.org/x/crypto/ssh/agent" ) // InstallCert adds the private key and signed certificate to the ssh agent. func InstallCert(a agent.Agent, cert *ssh.Certificate, key Key) error { t := time.Unix(int64(cert.ValidBefore), 0) lifetime := t.Sub(time.Now()).Seconds() comment := fmt.Sprintf("%s [Expires %s]", cert.KeyId, t) pubcert := agent.AddedKey{ PrivateKey: key, Certificate: cert, Comment: comment, LifetimeSecs: uint32(lifetime), } if err := a.Add(pubcert); err != nil { return fmt.Errorf("error importing certificate: %s", err) } privkey := agent.AddedKey{ PrivateKey: key, Comment: comment, LifetimeSecs: uint32(lifetime), } if err := a.Add(privkey); err != nil { return fmt.Errorf("error importing key: %s", err) } return nil } // send the signing request to the CA. func send(s []byte, token, ca string, ValidateTLSCertificate bool) (*lib.SignResponse, error) { transport := &http.Transport{ TLSClientConfig: &tls.Config{InsecureSkipVerify: !ValidateTLSCertificate}, } client := &http.Client{Transport: transport} u, err := url.Parse(ca) if err != nil { return nil, err } u.Path = path.Join(u.Path, "/sign") req, err := http.NewRequest("POST", u.String(), bytes.NewReader(s)) if err != nil { return nil, err } req.Header.Set("Content-Type", "application/json") req.Header.Add("Accept", "application/json") req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token)) resp, err := client.Do(req) if err != nil { return nil, err } if resp.StatusCode != http.StatusOK { return nil, fmt.Errorf("Bad response from server: %s", resp.Status) } defer resp.Body.Close() body, err := ioutil.ReadAll(resp.Body) if err != nil { return nil, err } c := &lib.SignResponse{} if err := json.Unmarshal(body, c); err != nil { return nil, err } return c, nil } // Sign sends the public key to the CA to be signed. func Sign(pub ssh.PublicKey, token string, conf *Config) (*ssh.Certificate, error) { validity, err := time.ParseDuration(conf.Validity) if err != nil { return nil, err } marshaled := ssh.MarshalAuthorizedKey(pub) // Remove the trailing newline. marshaled = marshaled[:len(marshaled)-1] s, err := json.Marshal(&lib.SignRequest{ Key: string(marshaled), ValidUntil: time.Now().Add(validity), }) if err != nil { return nil, err } resp, err := send(s, token, conf.CA, conf.ValidateTLSCertificate) if err != nil { return nil, err } if resp.Status != "ok" { return nil, fmt.Errorf("error: %s", resp.Response) } k, _, _, _, err := ssh.ParseAuthorizedKey([]byte(resp.Response)) if err != nil { return nil, err } cert, ok := k.(*ssh.Certificate) if !ok { return nil, fmt.Errorf("did not receive a certificate from server") } return cert, nil }