Rewrite identity and access management

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/iam/saml/sp.go

@@ -0,0 +1,68 @@
+// 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 (
+	"context"
+	"encoding/base64"
+	"fmt"
+
+	"github.com/crewjam/saml"
+	"go.probo.inc/probo/pkg/coredata"
+)
+
+func (s *Service) serviceProvider(
+	ctx context.Context,
+	config *coredata.SAMLConfiguration,
+) (*saml.ServiceProvider, error) {
+	cert, err := config.GetIdPCertificate()
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse IdP certificate: %w", err)
+	}
+
+	sp := s.baseServiceProvider()
+	sp.IDPMetadata = &saml.EntityDescriptor{
+		EntityID: config.IdPEntityID,
+		IDPSSODescriptors: []saml.IDPSSODescriptor{
+			{
+				SSODescriptor: saml.SSODescriptor{
+					RoleDescriptor: saml.RoleDescriptor{
+						ProtocolSupportEnumeration: "urn:oasis:names:tc:SAML:2.0:protocol",
+						KeyDescriptors: []saml.KeyDescriptor{
+							{
+								Use: "signing",
+								KeyInfo: saml.KeyInfo{
+									X509Data: saml.X509Data{
+										X509Certificates: []saml.X509Certificate{
+											{Data: base64.StdEncoding.EncodeToString(cert.Raw)},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+				SingleSignOnServices: []saml.Endpoint{
+					{
+						Binding:  saml.HTTPRedirectBinding,
+						Location: config.IdPSsoURL,
+					},
+				},
+			},
+		},
+	}
+
+	return sp, nil
+}