diff --git a/apps/api/src/lib/target-app.ts b/apps/api/src/lib/target-app.ts
index a6d8855..eacd04d 100644
--- a/apps/api/src/lib/target-app.ts
+++ b/apps/api/src/lib/target-app.ts
@@ -1,19 +1,32 @@
 import type { AuditSourceApp } from '@authportal/shared'
 
-/** Resolve SSO target app from return_to URL host/path. */
+/** Resolve SSO target app from return_to URL host/path (and OIDC authorize unwrap). */
 export function targetAppFromReturnTo(
   returnTo: string | undefined | null,
 ): AuditSourceApp {
   if (!returnTo) return 'portal'
   let host = ''
   let path = ''
+  let search = ''
   try {
     const u = new URL(returnTo)
     host = u.hostname.toLowerCase()
     path = u.pathname.toLowerCase()
+    search = u.search
   } catch {
     return 'portal'
   }
+
+  // Portal OIDC authorize as return_to → map via client's redirect_uri
+  if (path === '/oauth/authorize' || path.endsWith('/oauth/authorize')) {
+    try {
+      const redirectUri = new URLSearchParams(search).get('redirect_uri')
+      if (redirectUri) return targetAppFromReturnTo(redirectUri)
+    } catch {
+      /* ignore */
+    }
+  }
+
   const hay = `${host} ${path}`
   if (/\bvps\b/.test(hay) || host.includes('vps')) return 'vps'
   if (
diff --git a/apps/api/src/routes/oidc.ts b/apps/api/src/routes/oidc.ts
index 78bad7b..c816f42 100644
--- a/apps/api/src/routes/oidc.ts
+++ b/apps/api/src/routes/oidc.ts
@@ -18,6 +18,7 @@ import {
   normalizePermissionKeys,
 } from '@authportal/shared'
 import { oidcIssuerFromConfig } from '../config.js'
+import { clientIp, safeAudit } from '../lib/audit.js'
 import {
   buildJwks,
   buildOidcDiscovery,
@@ -25,6 +26,7 @@ import {
   signOidcJwt,
   verifyOidcAccessToken,
 } from '../lib/oidc/keys.js'
+import { clientUserAgent, targetAppFromReturnTo } from '../lib/target-app.js'
 
 const REFRESH_COOKIE = 'refresh_token'
 const CODE_TTL_MS = 5 * 60 * 1000
@@ -266,6 +268,27 @@ export async function oidcRoutes(app: FastifyInstance): Promise<void> {
       expiresAt: new Date(Date.now() + CODE_TTL_MS),
     })
 
+    const targetApp = targetAppFromReturnTo(redirectUri)
+    safeAudit(app, {
+      action: 'auth.sso_handoff',
+      severity: 'info',
+      actorUserId: user.id,
+      actorEmail: user.email,
+      actorName: user.name,
+      targetType: 'session',
+      targetId: user.id,
+      summary: `SSO OIDC: ${user.email} → ${targetApp}`,
+      details: {
+        return_to: redirectUri,
+        target_app: targetApp,
+        user_agent: clientUserAgent(request.headers),
+        oidc_client_id: client.clientId,
+        oidc_client_name: client.name,
+        auth_mode: 'oidc',
+      },
+      ip: clientIp(request),
+    })
+
     const dest = new URL(redirectUri)
     dest.searchParams.set('code', rawCode)
     if (state) dest.searchParams.set('state', state)
diff --git a/apps/api/test/oidc.test.ts b/apps/api/test/oidc.test.ts
index fae2ce1..3c51f9e 100644
--- a/apps/api/test/oidc.test.ts
+++ b/apps/api/test/oidc.test.ts
@@ -50,6 +50,66 @@ describe('OIDC IdP', () => {
     await app.close()
   })
 
+  it('records auth.sso_handoff with target_app dns on authorize', async () => {
+    const app = await buildTestApp()
+
+    const login = await app.inject({
+      method: 'POST',
+      url: '/api/v1/auth/login',
+      payload: { email: 'admin@test.local', password: 'adminpass' },
+    })
+    expect(login.statusCode).toBe(200)
+    const token = (login.json() as { access_token: string }).access_token
+    const refresh = login.cookies.find((c) => c.name === 'refresh_token')
+    expect(refresh?.value).toBeTruthy()
+
+    const created = await app.inject({
+      method: 'POST',
+      url: '/api/v1/admin/oidc/clients',
+      headers: { authorization: `Bearer ${token}` },
+      payload: {
+        name: 'Technitium',
+        redirect_uris: ['https://dns.test.local/sso/callback'],
+        scopes: ['openid', 'profile', 'email', 'groups'],
+        enabled: true,
+      },
+    })
+    const client = created.json() as { client_id: string }
+
+    const authorize = await app.inject({
+      method: 'GET',
+      url: '/oauth/authorize',
+      cookies: { refresh_token: refresh!.value },
+      query: {
+        client_id: client.client_id,
+        redirect_uri: 'https://dns.test.local/sso/callback',
+        response_type: 'code',
+        scope: 'openid profile email groups',
+        state: 'xyz',
+      },
+    })
+    expect(authorize.statusCode).toBe(302)
+
+    const audit = await app.inject({
+      method: 'GET',
+      url: '/api/v1/admin/audit?kind=logins&limit=50',
+      headers: { authorization: `Bearer ${token}` },
+    })
+    expect(audit.statusCode).toBe(200)
+    const entries = audit.json() as {
+      action: string
+      details: Record<string, unknown> | null
+    }[]
+    const handoff = entries.find(
+      (e) =>
+        e.action === 'auth.sso_handoff' &&
+        e.details?.target_app === 'dns' &&
+        e.details?.auth_mode === 'oidc',
+    )
+    expect(handoff).toBeTruthy()
+    await app.close()
+  })
+
   it('reloads RS256 key from SQLite after restart (extractable import)', async () => {
     const dir = mkdtempSync(join(tmpdir(), 'oidc-key-'))
     const dbPath = `sqlite:${join(dir, 'app.db')}`
diff --git a/apps/api/test/target-app.test.ts b/apps/api/test/target-app.test.ts
new file mode 100644
index 0000000..cfecc99
--- /dev/null
+++ b/apps/api/test/target-app.test.ts
@@ -0,0 +1,24 @@
+import { describe, expect, it } from 'vitest'
+import { targetAppFromReturnTo } from '../src/lib/target-app.js'
+
+describe('targetAppFromReturnTo', () => {
+  it('maps dns host and /sso/ path', () => {
+    expect(targetAppFromReturnTo('https://dns.shnt.top/sso/callback')).toBe(
+      'dns',
+    )
+  })
+
+  it('unwraps portal /oauth/authorize return_to via redirect_uri', () => {
+    const returnTo =
+      'https://auth.shnt.top/oauth/authorize?client_id=abc&redirect_uri=' +
+      encodeURIComponent('https://dns.shnt.top/sso/callback') +
+      '&response_type=code&scope=openid'
+    expect(targetAppFromReturnTo(returnTo)).toBe('dns')
+  })
+
+  it('keeps portal for bare issuer authorize without redirect_uri', () => {
+    expect(
+      targetAppFromReturnTo('https://auth.shnt.top/oauth/authorize'),
+    ).toBe('portal')
+  })
+})
diff --git a/docs/integrate-technitium.md b/docs/integrate-technitium.md
index 17aa434..9d68018 100644
--- a/docs/integrate-technitium.md
+++ b/docs/integrate-technitium.md
@@ -88,6 +88,8 @@ curl -fsS http://localhost:8080/.well-known/openid-configuration | head
 
 Для `dns` режим `authMode: oidc` — открывается базовый URL (кнопка OpenID Connect на логине Technitium), без `#access_token`.
 
+Журнал входов портала: при выдаче authorization code пишется `auth.sso_handoff` с `target_app: dns` (колонка «Приложение» → Technitium DNS).
+
 ## Endpoints portal (IdP)
 
 - `GET /.well-known/openid-configuration`