feat(ldap): opt-in skip TLS verification for ldaps (internal CA)

Add a per-tenant "Skip TLS certificate verification" toggle to the LDAP
admin page so admins can connect to an AD whose ldaps:// certificate is
signed by an internal/self-signed CA (Node error: "unable to verify the
first certificate"). When enabled, ldapts is given
tlsOptions.rejectUnauthorized=false; the flag is ignored for plain ldap://
(no TLS). Defaults to full verification.

New Boolean column LdapConfig.tlsRejectUnauthorized (@default(true)) +
migration; wired through DTOs, config service, all Client creations
(test/groups/user-search/import/sync) and the test-connection endpoint. UI
checkbox with an insecure-network warning (de/en). 3 new service specs;
API 218 green, web 131 green, both apps tsc clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/api/prisma/migrations/20260722180000_ldap_tls_reject_unauthorized/migration.sql

@@ -0,0 +1,2 @@
+-- Add opt-in TLS verification skip for ldaps:// (internal/private CA AD certs).
+ALTER TABLE "LdapConfig" ADD COLUMN IF NOT EXISTS "tlsRejectUnauthorized" BOOLEAN NOT NULL DEFAULT true;

apps/api/prisma/schema.prisma

@@ -69,6 +69,7 @@ model LdapConfig {
   searchFilter    String             @default("(objectClass=person)")
   syncIntervalMin Int                @default(60)
   isActive        Boolean            @default(true)
+  tlsRejectUnauthorized Boolean       @default(true)
   groupFilterDns  String[]           @default([])
   userExcludeList String[]           @default([])
   lastSyncAt      DateTime?

apps/api/src/ldap/dto/ldap-config.dto.ts

@@ -43,6 +43,10 @@ export class CreateLdapConfigDto {
   @IsOptional()
   isActive?: boolean;
 
+  @IsBoolean()
+  @IsOptional()
+  tlsRejectUnauthorized?: boolean;
+
   @IsArray()
   @IsString({ each: true })
   @IsOptional()
@@ -76,6 +80,10 @@ export class TestConnectionDto {
   @IsString()
   @IsOptional()
   bindPassword?: string;
+
+  @IsBoolean()
+  @IsOptional()
+  tlsRejectUnauthorized?: boolean;
 }
 
 /**

apps/api/src/ldap/ldap-config.service.ts

@@ -39,6 +39,7 @@ export class LdapConfigService {
         searchFilter: dto.searchFilter ?? '(objectClass=person)',
         syncIntervalMin: dto.syncIntervalMin ?? 60,
         isActive: dto.isActive ?? true,
+        tlsRejectUnauthorized: dto.tlsRejectUnauthorized ?? true,
         groupFilterDns: dto.groupFilterDns ?? [],
         userExcludeList: dto.userExcludeList ?? [],
         fieldMappings: {
@@ -81,6 +82,9 @@ export class LdapConfigService {
           syncIntervalMin: dto.syncIntervalMin,
         }),
         ...(dto.isActive !== undefined && { isActive: dto.isActive }),
+        ...(dto.tlsRejectUnauthorized !== undefined && {
+          tlsRejectUnauthorized: dto.tlsRejectUnauthorized,
+        }),
         ...(dto.groupFilterDns !== undefined && {
           groupFilterDns: dto.groupFilterDns,
         }),

apps/api/src/ldap/ldap.controller.ts

@@ -133,6 +133,9 @@ export class LdapController {
     const serverUrl = dto.serverUrl || config?.serverUrl;
     const bindDn = dto.bindDn || config?.bindDn;
     const bindPassword = dto.bindPassword || config?.bindPassword;
+    // Explicit form value wins; otherwise fall back to the saved config.
+    const tlsRejectUnauthorized =
+      dto.tlsRejectUnauthorized ?? config?.tlsRejectUnauthorized;
 
     if (!serverUrl) {
       throw new BadRequestException(
@@ -140,7 +143,12 @@ export class LdapController {
       );
     }
 
-    return this.ldapService.testConnection({ serverUrl, bindDn, bindPassword });
+    return this.ldapService.testConnection({
+      serverUrl,
+      bindDn,
+      bindPassword,
+      tlsRejectUnauthorized,
+    });
   }
 
   /**
@@ -165,6 +173,7 @@ export class LdapController {
       baseDn: config.baseDn,
       bindDn: config.bindDn,
       bindPassword: config.bindPassword,
+      tlsRejectUnauthorized: config.tlsRejectUnauthorized,
     });
   }
 
@@ -191,6 +200,7 @@ export class LdapController {
         baseDn: config.baseDn,
         bindDn: config.bindDn,
         bindPassword: config.bindPassword,
+        tlsRejectUnauthorized: config.tlsRejectUnauthorized,
       },
       tenantId,
       q ?? '',
@@ -223,6 +233,7 @@ export class LdapController {
         baseDn: config.baseDn,
         bindDn: config.bindDn,
         bindPassword: config.bindPassword,
+        tlsRejectUnauthorized: config.tlsRejectUnauthorized,
         searchFilter: config.searchFilter,
         groupFilterDns: config.groupFilterDns,
         userExcludeList: config.userExcludeList,
@@ -258,6 +269,7 @@ export class LdapController {
         baseDn: config.baseDn,
         bindDn: config.bindDn,
         bindPassword: config.bindPassword,
+        tlsRejectUnauthorized: config.tlsRejectUnauthorized,
         searchFilter: config.searchFilter,
         groupFilterDns: config.groupFilterDns,
         userExcludeList: config.userExcludeList,

apps/api/src/ldap/ldap.service.spec.ts

@@ -20,6 +20,7 @@ vi.mock('../prisma/prisma-tenant.extension', () => ({
   forTenant: vi.fn((p: unknown) => p),
 }));
 
+import { Client } from 'ldapts';
 import { LdapService } from './ldap.service';
 
 describe('LdapService.syncUsersForTenant — per-user exclude list', () => {
@@ -265,3 +266,45 @@ describe('LdapService — individual user search & import (dedup)', () => {
     expect(userService.create).not.toHaveBeenCalled();
   });
 });
+
+describe('LdapService.testConnection — TLS verification opt-out (ldaps)', () => {
+  let service: LdapService;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockBind.mockResolvedValue(undefined);
+    mockUnbind.mockResolvedValue(undefined);
+    service = new LdapService({} as any, {} as any);
+  });
+
+  it('passes tlsOptions.rejectUnauthorized=false for ldaps when opted out', async () => {
+    await service.testConnection({
+      serverUrl: 'ldaps://ad:636',
+      tlsRejectUnauthorized: false,
+    });
+    expect(Client).toHaveBeenCalledWith(
+      expect.objectContaining({
+        url: 'ldaps://ad:636',
+        tlsOptions: { rejectUnauthorized: false },
+      }),
+    );
+  });
+
+  it('keeps verification on for ldaps when tlsRejectUnauthorized is true', async () => {
+    await service.testConnection({
+      serverUrl: 'ldaps://ad:636',
+      tlsRejectUnauthorized: true,
+    });
+    const opts = (Client as any).mock.calls.at(-1)[0];
+    expect(opts.tlsOptions).toBeUndefined();
+  });
+
+  it('ignores the flag for plain ldap:// (no TLS)', async () => {
+    await service.testConnection({
+      serverUrl: 'ldap://ad:389',
+      tlsRejectUnauthorized: false,
+    });
+    const opts = (Client as any).mock.calls.at(-1)[0];
+    expect(opts.tlsOptions).toBeUndefined();
+  });
+});

apps/api/src/ldap/ldap.service.ts

@@ -25,6 +25,9 @@ interface LdapConfigData {
   bindDn?: string | null;
   bindPassword?: string | null;
   searchFilter: string;
+  // When false, skip TLS certificate verification for ldaps:// (internal CA
+  // / self-signed AD certs). Ignored for plain ldap://. Default true.
+  tlsRejectUnauthorized?: boolean | null;
   groupFilterDns: string[];
   userExcludeList: string[];
   fieldMappings: Array<{
@@ -97,6 +100,27 @@ export class LdapService {
     await client.bind(bindDn || '', bindPassword || '');
   }
 
+  /**
+   * Build ldapts Client options. For ldaps:// connections, honor an opt-in
+   * "skip TLS verification" flag (tlsRejectUnauthorized === false) so admins
+   * can connect to an AD whose certificate is signed by an internal/private
+   * CA that Node doesn't trust ("unable to verify the first certificate").
+   * Ignored for plain ldap:// (no TLS). Default is full verification.
+   */
+  private buildClientOptions(
+    serverUrl: string,
+    tlsRejectUnauthorized?: boolean | null,
+  ): ConstructorParameters<typeof Client>[0] {
+    const options: ConstructorParameters<typeof Client>[0] = { url: serverUrl };
+    if (
+      serverUrl.toLowerCase().startsWith('ldaps') &&
+      tlsRejectUnauthorized === false
+    ) {
+      options.tlsOptions = { rejectUnauthorized: false };
+    }
+    return options;
+  }
+
   /**
    * Test LDAP connection with given configuration.
    * Returns success/failure with optional error message.
@@ -105,8 +129,11 @@ export class LdapService {
     serverUrl: string;
     bindDn?: string | null;
     bindPassword?: string | null;
+    tlsRejectUnauthorized?: boolean | null;
   }): Promise<{ success: boolean; error?: string }> {
-    const client = new Client({ url: config.serverUrl });
+    const client = new Client(
+      this.buildClientOptions(config.serverUrl, config.tlsRejectUnauthorized),
+    );
 
     try {
       await this.bind(client, config.bindDn, config.bindPassword);
@@ -135,8 +162,11 @@ export class LdapService {
     baseDn: string;
     bindDn?: string | null;
     bindPassword?: string | null;
+    tlsRejectUnauthorized?: boolean | null;
   }): Promise<LdapDirectoryEntry[]> {
-    const client = new Client({ url: config.serverUrl });
+    const client = new Client(
+      this.buildClientOptions(config.serverUrl, config.tlsRejectUnauthorized),
+    );
 
     try {
       await this.bind(client, config.bindDn, config.bindPassword);
@@ -263,6 +293,7 @@ export class LdapService {
       baseDn: string;
       bindDn?: string | null;
       bindPassword?: string | null;
+      tlsRejectUnauthorized?: boolean | null;
     },
     tenantId: string,
     query: string,
@@ -272,7 +303,9 @@ export class LdapService {
       return [];
     }
 
-    const client = new Client({ url: config.serverUrl });
+    const client = new Client(
+      this.buildClientOptions(config.serverUrl, config.tlsRejectUnauthorized),
+    );
     const first = (v: unknown): string =>
       Array.isArray(v) ? String(v[0] ?? '') : v != null ? String(v) : '';
 
@@ -350,7 +383,9 @@ export class LdapService {
       errors: [],
     };
 
-    const client = new Client({ url: config.serverUrl });
+    const client = new Client(
+      this.buildClientOptions(config.serverUrl, config.tlsRejectUnauthorized),
+    );
     const excludeSet = new Set(
       (config.userExcludeList ?? [])
         .map((u) => u.trim().toLowerCase())
@@ -464,7 +499,9 @@ export class LdapService {
       errors: [],
     };
 
-    const client = new Client({ url: config.serverUrl });
+    const client = new Client(
+      this.buildClientOptions(config.serverUrl, config.tlsRejectUnauthorized),
+    );
 
     // Create tenant-scoped Prisma client per Pitfall 2
     const tenantPrisma = forTenant(this.prisma, tenantId) as any;