Files
probo/pkg/iam/saml/saml_metadata.go
Bryan Frimin 74fc3b8cd1 Rewrite identity and access management
Signed-off-by: Bryan Frimin <bryan@getprobo.com>
2026-01-17 10:07:34 -08:00

88 lines
2.9 KiB
Go

// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
package saml
import (
"crypto/x509"
"encoding/base64"
"encoding/xml"
"fmt"
"github.com/crewjam/saml"
)
func ParseIdpMetadata(metadataXML []byte) (string, string, *x509.Certificate, error) {
var entityDescriptor saml.EntityDescriptor
err := xml.Unmarshal(metadataXML, &entityDescriptor)
if err != nil {
return "", "", nil, fmt.Errorf("cannot parse metadata XML: %w", err)
}
if len(entityDescriptor.IDPSSODescriptors) == 0 {
return "", "", nil, fmt.Errorf("no IDPSSODescriptor found in metadata")
}
idpDescriptor := entityDescriptor.IDPSSODescriptors[0]
ssoURL, err := getSsoURLFromMetadata(idpDescriptor)
if err != nil {
return "", "", nil, fmt.Errorf("cannot get SSO URL from metadata: %w", err)
}
cert, err := getCertificateFromMetadata(idpDescriptor)
if err != nil {
return "", "", nil, fmt.Errorf("cannot get certificate from metadata: %w", err)
}
return entityDescriptor.EntityID, ssoURL, cert, nil
}
func getSsoURLFromMetadata(idpDescriptor saml.IDPSSODescriptor) (string, error) {
for _, sso := range idpDescriptor.SingleSignOnServices {
if sso.Binding == saml.HTTPPostBinding || sso.Binding == saml.HTTPRedirectBinding {
return sso.Location, nil
}
}
if len(idpDescriptor.SingleSignOnServices) > 0 {
return idpDescriptor.SingleSignOnServices[0].Location, nil
}
return "", fmt.Errorf("no SingleSignOnService found in metadata")
}
func getCertificateFromMetadata(idpDescriptor saml.IDPSSODescriptor) (*x509.Certificate, error) {
for _, keyDescriptor := range idpDescriptor.KeyDescriptors {
if keyDescriptor.Use == "signing" || keyDescriptor.Use == "" {
if len(keyDescriptor.KeyInfo.X509Data.X509Certificates) > 0 {
certData := keyDescriptor.KeyInfo.X509Data.X509Certificates[0].Data
certDER, err := base64.StdEncoding.DecodeString(certData)
if err != nil {
return nil, fmt.Errorf("cannot decode certificate: %w", err)
}
cert, err := x509.ParseCertificate(certDER)
if err != nil {
return nil, fmt.Errorf("cannot parse certificate: %w", err)
}
return cert, nil
}
}
}
return nil, fmt.Errorf("no signing certificate found in metadata")
}