feat(auth): per-org OIDC resolver replaces global provider

server/internal/auth/middleware.go

@@ -37,11 +37,6 @@ func UserID(c *gin.Context) string {
 
 func Middleware() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		if !authEnabled {
-			c.Next()
-			return
-		}
-
 		cookie, err := c.Request.Cookie(sessionCookieName)
 		if err != nil {
 			c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "not authenticated"})

server/internal/auth/oidc.go

@@ -2,114 +2,149 @@ package auth
 
 import (
 	"context"
-	"log"
+	"fmt"
 	"net/http"
-	"os"
+	"strings"
+	"sync"
 
 	"github.com/coreos/go-oidc/v3/oidc"
 	"github.com/gin-gonic/gin"
+	"github.com/mrhid6/vantage/server/internal/services"
 	"golang.org/x/oauth2"
 )
 
-var (
-	oidcProvider *oidc.Provider
-	oauth2Cfg    *oauth2.Config
-	authEnabled  bool
-)
-
-func InitOIDC(ctx context.Context) error {
-	issuer := os.Getenv("OIDC_ISSUER")
-	if issuer == "" {
-		log.Println("OIDC_ISSUER not set; authentication disabled")
-		return nil
-	}
-
-	p, err := oidc.NewProvider(ctx, issuer)
-	if err != nil {
-		return err
-	}
-	oidcProvider = p
-	oauth2Cfg = &oauth2.Config{
-		ClientID:     os.Getenv("OIDC_CLIENT_ID"),
-		ClientSecret: os.Getenv("OIDC_CLIENT_SECRET"),
-		RedirectURL:  os.Getenv("OIDC_REDIRECT_URL"),
-		Endpoint:     p.Endpoint(),
-		Scopes:       []string{oidc.ScopeOpenID, "profile", "email"},
-	}
-	authEnabled = true
-	log.Println("OIDC authentication enabled")
-	return nil
+type orgProvider struct {
+	provider *oidc.Provider
+	oauth    *oauth2.Config
 }
 
-func Enabled() bool { return authEnabled }
+var (
+	provMu    sync.Mutex
+	provCache = map[string]*orgProvider{}
+)
 
-func HandleLogin(c *gin.Context) {
-	state, err := randomHex(16)
+func redirectURL(c *gin.Context) string {
+	scheme := "https"
+	if c.Request.TLS == nil && c.GetHeader("X-Forwarded-Proto") != "https" {
+		scheme = "http"
+	}
+	return fmt.Sprintf("%s://%s/auth/oidc/callback", scheme, c.Request.Host)
+}
+
+func providerForOrg(ctx context.Context, c *gin.Context, orgID string) (*orgProvider, error) {
+	cfg, err := services.GetOrgOIDC(orgID)
+	if err != nil || !cfg.Enabled {
+		return nil, fmt.Errorf("org SSO not configured")
+	}
+	secret, err := services.GetOrgOIDCSecret(orgID)
 	if err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{"error": "state generation failed"})
+		return nil, err
+	}
+	provMu.Lock()
+	op := provCache[orgID]
+	provMu.Unlock()
+	if op == nil || op.provider == nil {
+		p, err := oidc.NewProvider(ctx, cfg.Issuer)
+		if err != nil {
+			return nil, err
+		}
+		op = &orgProvider{provider: p}
+		provMu.Lock()
+		provCache[orgID] = op
+		provMu.Unlock()
+	}
+	op.oauth = &oauth2.Config{
+		ClientID: cfg.ClientID, ClientSecret: secret,
+		RedirectURL: redirectURL(c), Endpoint: op.provider.Endpoint(),
+		Scopes: []string{oidc.ScopeOpenID, "profile", "email"},
+	}
+	return op, nil
+}
+
+func HandleOIDCStart(c *gin.Context) {
+	org, ok := OrgFromHost(c)
+	if !ok {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "unknown organization host"})
 		return
 	}
-	if err := SaveState(c.Request.Context(), state); err != nil {
+	ctx := c.Request.Context()
+	op, err := providerForOrg(ctx, c, org.OrgID)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	state, err := randomHex(16)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "state gen failed"})
+		return
+	}
+	if err := SaveStateOrg(ctx, state, org.OrgID); err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "state save failed"})
 		return
 	}
-	c.Redirect(http.StatusFound, oauth2Cfg.AuthCodeURL(state))
+	c.Redirect(http.StatusFound, op.oauth.AuthCodeURL(state))
 }
 
-func HandleCallback(c *gin.Context) {
+func HandleOIDCCallback(c *gin.Context) {
 	ctx := c.Request.Context()
-
-	if !ConsumeState(ctx, c.Query("state")) {
+	orgID, ok := ConsumeStateOrg(ctx, c.Query("state"))
+	if !ok {
 		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid state"})
 		return
 	}
-
-	token, err := oauth2Cfg.Exchange(ctx, c.Query("code"))
+	op, err := providerForOrg(ctx, c, orgID)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	token, err := op.oauth.Exchange(ctx, c.Query("code"))
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "token exchange failed"})
 		return
 	}
-
 	rawIDToken, ok := token.Extra("id_token").(string)
 	if !ok {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "missing id_token"})
 		return
 	}
-
-	verifier := oidcProvider.Verifier(&oidc.Config{ClientID: oauth2Cfg.ClientID})
-	idToken, err := verifier.Verify(ctx, rawIDToken)
+	idToken, err := op.provider.Verifier(&oidc.Config{ClientID: op.oauth.ClientID}).Verify(ctx, rawIDToken)
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "token verification failed"})
 		return
 	}
-
 	var claims struct {
-		Sub   string `json:"sub"`
 		Email string `json:"email"`
 		Name  string `json:"name"`
 	}
-	if err := idToken.Claims(&claims); err != nil {
+	if err := idToken.Claims(&claims); err != nil || claims.Email == "" {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "claims extraction failed"})
 		return
 	}
 
+	email := strings.ToLower(claims.Email)
+	u, err := services.GetUserByEmail(email)
+	if err != nil {
+		// provision new member in THIS org
+		u, err = services.CreateUser(orgID, email, "", "member", "oidc")
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "provisioning failed"})
+			return
+		}
+	} else if u.OrgID != orgID {
+		c.JSON(http.StatusForbidden, gin.H{"error": "email belongs to a different organization"})
+		return
+	}
+
 	sessionID, err := SaveSession(ctx, &Session{
-		UserID: claims.Sub,
-		Email:  claims.Email,
-		Name:   claims.Name,
+		UserID: u.UserID, OrgID: u.OrgID, Role: u.Role, Email: u.Email, Name: claims.Name,
 	})
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "session save failed"})
 		return
 	}
-
+	_ = services.TouchLastLogin(u.UserID)
 	SetSessionCookie(c, sessionID)
-
-	frontendURL := os.Getenv("PUBLIC_HOST")
-	if frontendURL == "" {
-		frontendURL = "/"
-	}
-	c.Redirect(http.StatusFound, frontendURL)
+	c.Redirect(http.StatusFound, "/")
 }
 
 func HandleLogout(c *gin.Context) {

server/internal/auth/session.go

@@ -71,11 +71,14 @@ func DeleteSession(ctx context.Context, id string) error {
 	return rdb.Del(ctx, sessionPrefix+id).Err()
 }
 
-func SaveState(ctx context.Context, state string) error {
-	return rdb.Set(ctx, statePrefix+state, "1", 10*time.Minute).Err()
+func SaveStateOrg(ctx context.Context, state, orgID string) error {
+	return rdb.Set(ctx, statePrefix+state, orgID, 10*time.Minute).Err()
 }
 
-func ConsumeState(ctx context.Context, state string) bool {
-	n, err := rdb.Del(ctx, statePrefix+state).Result()
-	return err == nil && n > 0
+func ConsumeStateOrg(ctx context.Context, state string) (string, bool) {
+	orgID, err := rdb.GetDel(ctx, statePrefix+state).Result()
+	if err != nil || orgID == "" {
+		return "", false
+	}
+	return orgID, true
 }