refactor: extract cert generation to core/

app/lib/provider/persistence_provider.dart

@@ -166,7 +166,7 @@ class PersistenceService {
     }
 
     if (prefs.getString(_securityContext) == null) {
-      await prefs.setString(_securityContext, jsonEncode(generateSecurityContext()));
+      await prefs.setString(_securityContext, jsonEncode(await generateSecurityContext()));
     }
 
     if (isFirstAppStart) {

app/lib/provider/security_provider.dart

@@ -30,7 +30,7 @@ class SecurityService extends ReduxNotifier<StoredSecurityContext> {
 class ResetSecurityContextAction extends AsyncReduxAction<SecurityService, StoredSecurityContext> {
   @override
   Future<StoredSecurityContext> reduce() async {
-    final securityContext = generateSecurityContext();
+    final securityContext = await generateSecurityContext();
     await notifier._persistence.setSecurityContext(securityContext);
     return securityContext;
   }

app/lib/util/security_helper.dart

@@ -1,67 +1,17 @@
-import 'dart:convert';
-import 'dart:typed_data';
-
-import 'package:basic_utils/basic_utils.dart';
-import 'package:convert/convert.dart';
 import 'package:localsend_isolates/model/stored_security_context.dart';
 import 'package:localsend_isolates/rust/api/crypto.dart' as rust;
 
-/// Generates a random [SecurityContextResult].
-StoredSecurityContext generateSecurityContext([AsymmetricKeyPair? keyPair]) {
-  keyPair ??= CryptoUtils.generateRSAKeyPair();
-  final privateKey = keyPair.privateKey as RSAPrivateKey;
-  final publicKey = keyPair.publicKey as RSAPublicKey;
-  final dn = {
-    'CN': 'LocalSend User',
-    'O': '',
-    'OU': '',
-    'L': '',
-    'S': '',
-    'C': '',
-  };
-  final csr = X509Utils.generateRsaCsrPem(dn, privateKey, publicKey);
-  final certificate = X509Utils.generateSelfSignedCertificate(keyPair.privateKey, csr, 365 * 10);
-
-  final hash = calculateHashOfCertificate(certificate);
-  final spki = extractPublicKeyFromCertificate(certificate);
-
+/// Generates a random [StoredSecurityContext].
+Future<StoredSecurityContext> generateSecurityContext() async {
+  final result = await rust.generateSecurityContext();
   return StoredSecurityContext(
-    privateKey: CryptoUtils.encodeRSAPrivateKeyToPemPkcs1(privateKey),
-    publicKey: spki,
-    certificate: certificate,
-    certificateHash: hash,
+    privateKey: result.privateKey,
+    publicKey: result.publicKey,
+    certificate: result.certificate,
+    certificateHash: result.certificateHash,
   );
 }
 
-/// Calculates the hash of a certificate.
-String calculateHashOfCertificate(String certificate) {
-  // Convert PEM to DER
-  final pemContent = certificate.replaceAll('\r\n', '\n').split('\n').where((line) => line.isNotEmpty && !line.startsWith('---')).join();
-  final der = base64Decode(pemContent);
-
-  // Calculate hash
-  return CryptoUtils.getHash(
-    Uint8List.fromList(der),
-    algorithmName: 'SHA-256',
-  );
-}
-
-String extractPublicKeyFromCertificate(String certificate) {
-  final cert = X509Utils.x509CertificateFromPem(certificate);
-  final publicHex = cert.tbsCertificate!.subjectPublicKeyInfo.bytes!;
-  return _hexToSpkiPem(publicHex);
-}
-
-String _hexToSpkiPem(String hexBytes) {
-  final publicBytes = hex.decode(hexBytes);
-  final publicBase64 = base64Encode(publicBytes);
-  final temp =
-      '''-----BEGIN PUBLIC KEY-----
-$publicBase64
------END PUBLIC KEY-----''';
-  return X509Utils.fixPem(temp);
-}
-
 /// Verifies a certificate with a public key.
 /// Throws an exception if the certificate is invalid.
 Future<void> verifyCertificate({

app/pubspec.lock

@@ -73,14 +73,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.13.1"
-  basic_utils:
-    dependency: "direct main"
-    description:
-      name: basic_utils
-      sha256: "548047bef0b3b697be19fa62f46de54d99c9019a69fb7db92c69e19d87f633c7"
-      url: "https://pub.dev"
-    source: hosted
-    version: "5.8.2"
   boolean_selector:
     dependency: transitive
     description:
@@ -226,7 +218,7 @@ packages:
     source: hosted
     version: "2.1.0"
   convert:
-    dependency: "direct main"
+    dependency: transitive
     description:
       name: convert
       sha256: b30acd5944035672bc15c6b7a8b47d773e41e2f17de064350988c5d02adb1c68
@@ -1263,14 +1255,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.8"
-  pointycastle:
-    dependency: transitive
-    description:
-      name: pointycastle
-      sha256: "92aa3841d083cc4b0f4709b5c74fd6409a3e6ba833ffc7dc6a8fee096366acf5"
-      url: "https://pub.dev"
-    source: hosted
-    version: "4.0.0"
   pool:
     dependency: transitive
     description:

app/pubspec.yaml

@@ -10,10 +10,8 @@ environment:
   sdk: ^3.11.0
 
 dependencies:
-  basic_utils: 5.8.2
   collection: ^1.17.2 # allow newer versions, so it can compile with newer Flutter versions
   connectivity_plus: 7.2.0
-  convert: 3.1.2
   dart_mappable: 4.8.0
   desktop_drop: 0.7.1
   device_apps: 2.2.0

app/test/unit/util/security_helper_test.dart

@@ -1,105 +0,0 @@
-import 'package:basic_utils/basic_utils.dart';
-import 'package:localsend_app/util/security_helper.dart';
-import 'package:test/test.dart';
-
-void main() {
-  group('generateSecurityContext', () {
-    // certificate is dependent on time, so we skip this test
-    test('should generate a security context', () {
-      const modulus =
-          '17655370025740741038113156454854199388193503449104440877037318492305460691763108986359629213738068251658702764711191809795804339624629386590749322066892437190139062703234048708020881575102122778994526543290880868262952627726488977960776519938694907994518427540419624537894956809241753063372413058294447378662255052300193831939738828105579615087656442141880311261067266950751778487270744852541404898857201772242498437323791185553734672978477936608290952211534467577849886694581791190994405933665028620559373744808123499229584489594678456882464781972729864955090923226165749030219906764402228914184366893373631422503021';
-      const privateExponent =
-          '14421008176265737041842552728760854897987189421761902811979258986703749275840685218255600827633436556136869519473805770330945910011841184271318521744401163544644005150782334580299156378790480712915696482733480991790654395453357362699213084041660086971551428119477591606848878236042545176547425781216107887562053872086603693550866169434312772263069345523523039280590638079481520003143359443743141464111595442124530326974852967024986370324441963907065113439224776888067662971143404975436160178871895218249902778285379960904695389191962540588337134680308483675532942364276364403564632886857709821444086544738315317174145';
-      const privateP =
-          '178524065934350447993678840182944627942309006340524319909851831752106332954026000610471033106817833873729348468467401050633468292518369706764968836071362023882930741070266054692417392199462715540565991951570137107225695543150432250384310373010291328019775467135529294964213555809388513634733256540639643918349';
-      const privateQ =
-          '98896302486373120089171491460892017227056533661820429564718404666288200233919205658787592871460875274200632466484814562010402123837563042503616158962868253836369412258319855713924996179145010239261725685588005640861685432715579085801665010203646507394652948031357507454692937609788924433344012456182622364129';
-      const publicExponent = '65537';
-
-      final keyPair = AsymmetricKeyPair(
-        RSAPublicKey(
-          BigInt.parse(modulus),
-          BigInt.parse(publicExponent),
-        ),
-        RSAPrivateKey(
-          BigInt.parse(modulus),
-          BigInt.parse(privateExponent),
-          BigInt.parse(privateP),
-          BigInt.parse(privateQ),
-        ),
-      );
-
-      final context = generateSecurityContext(keyPair);
-      expect(
-        context.privateKey,
-        '''-----BEGIN RSA PRIVATE KEY-----
-MIIEpAIBAAKCAQEAi9uDMYRn63SZtEPGRogZGdu5XXBAoQeMO60mycoinqLKDWyZ
-dpMo+XWY3wYVhoAyxgzDOcPjIf+Uq1oEy/0K4WwfpbK8SCy851qgYkfMCT9D9mFv
-XwWoULJCUHFF7f947ArDE1nmuK1nNx2RodN2wJCXyzPjw0jn06bwGeg0EqfUC8wv
-W4FTZ6t1tErzmRqRdMUWuCJwsk1IMbDbFePhiK5jecOBG0RVVWLuw+TkuX8TUgrp
-IktH2+qEM1KdLyAMnL71hx2wMvE+lDKFKK9p37zXK8omjl+VgTC8ocjGeYDDsl43
-ZtW09V0pb7Vz2FM8b7BgM06kvJl48PIe5puYbQIDAQABAoIBAHI8hAW/TA7j9+Rp
-c5wK8M3RTrCGzxN5Ec9w2Hz80ZhYCcg7S4KyI0bYCl0pIA3zywVASXp2iaEsnSf1
-aHOipe+JHLSAsRAXEtm6icSdNojbF005OvoXqer4H/iK/X6wLPpItByrUyzH3sYD
-LgBLtPUHZiWBpenONCYKdpYCt/3/uyAeC4qj+sBlfN5Fio2A86qIgntg3n6he8Cd
-Yq0cjyEGzRnIa9EUDHoHUU30oPPj16LkK0uZxR7H+UKZkYNXQUGtPt0cnAvgS/2f
-UnOAIZop1r9NkS7sntg4l9iuDqI4xYMg9wtBStrgLx65nV1l4HDNZGq/LDo3msam
-NQoeX4ECgYEA/joJk42iTF3D2IJjFzMf539V9D/1OaXcxmiLMODsIW8ZcyKRRmzD
-NIBfMxX/0+X8IgkMwkcnZWOFMWw+2FDgfz2l+PMACJvGEGokxFDiJe68W4KAy8dr
-uB0M0ydhRWLG4ZD6U+gvwyqqlMNpEosCH0fJilag+tW/fx6ti2MBYA0CgYEAjNVA
-HItnlpnOmzOuyQob9kqE/8eDTSeX5ZFD/OZOypvLPukdg6qWnzaBzUgSJg/Tl9RD
-XWE9WgKc2Gpki7/EYvtRW4YwBcoZKBTkAio4t8WBRmLT6L3PUKKdJHOtFbmwlUPw
-mfw9HdJG/TgDiTlyAdTbuGhGY/unuUdPMvt2oeECgYEApthqHoeOo3XKKZbw93Hb
-F3AvdhxfkVT0ftZvu0VyU0L5veFK3KBWwGcbk4h1nJjMj33G/N370gOtj1EOMaNq
-ordP7QF13TB2naE7vgejU+fJgHk2lAauAGg4WX/3y7TW94TRdS3l4r1mtDlHBR9r
-5iGT+JGAFv8fLYtxtA/nACUCgYAb6Gpi/bESY/pQQSaiyjEOVmgSs7uuP2lXYbkC
-VbVJayQUnGdv3w8oD8obHuwRxNMeZD7RM2LQAnKIZFT2aJMHNlxB8c50Zz8i9TjV
-wP4qVKYwh4cMuQhrJz5SqeWjx39ZpPP538VQsonExiPVPp/8Au1jlq5UQ9tR2PK1
-3KT+oQKBgQCkmNd8ZHKBoIbG3oV0T4f4IFk8424QD5hQX7Zmb7gxwnCgQScOPBM/
-tk4v/rwNoiO9EUW4w4zZZIlvcFJu38+9pPX+rTFxGh6TZ6aRvw7962m2RBmqgYcq
-IWwwBbDLI6KuU/iqqvk/1syLDHqeaCdDqTmmyoaKKa7kUhkZkhIlLw==
------END RSA PRIVATE KEY-----''',
-      );
-
-      expect(
-        context.publicKey,
-        '''-----BEGIN PUBLIC KEY-----
-MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAi9uDMYRn63SZtEPGRogZ
-Gdu5XXBAoQeMO60mycoinqLKDWyZdpMo+XWY3wYVhoAyxgzDOcPjIf+Uq1oEy/0K
-4WwfpbK8SCy851qgYkfMCT9D9mFvXwWoULJCUHFF7f947ArDE1nmuK1nNx2RodN2
-wJCXyzPjw0jn06bwGeg0EqfUC8wvW4FTZ6t1tErzmRqRdMUWuCJwsk1IMbDbFePh
-iK5jecOBG0RVVWLuw+TkuX8TUgrpIktH2+qEM1KdLyAMnL71hx2wMvE+lDKFKK9p
-37zXK8omjl+VgTC8ocjGeYDDsl43ZtW09V0pb7Vz2FM8b7BgM06kvJl48PIe5puY
-bQIDAQAB
------END PUBLIC KEY-----''',
-      );
-    });
-  });
-
-  group('calculateHashOfCertificate', () {
-    test('should calculate hash of certificate', () {
-      const certificate = '''-----BEGIN CERTIFICATE-----
-MIIDGTCCAgGgAwIBAgIBATANBgkqhkiG9w0BAQsFADBQMRcwFQYDVQQDEw5Mb2Nh
-bFNlbmQgVXNlcjEJMAcGA1UEChMAMQkwBwYDVQQLEwAxCTAHBgNVBAcTADEJMAcG
-A1UECBMAMQkwBwYDVQQGEwAwHhcNMjMwNDIxMjM0NTM3WhcNMzMwNDE4MjM0NTM3
-WjBQMRcwFQYDVQQDEw5Mb2NhbFNlbmQgVXNlcjEJMAcGA1UEChMAMQkwBwYDVQQL
-EwAxCTAHBgNVBAcTADEJMAcGA1UECBMAMQkwBwYDVQQGEwAwggEiMA0GCSqGSIb3
-DQEBAQUAA4IBDwAwggEKAoIBAQCL24MxhGfrdJm0Q8ZGiBkZ27ldcEChB4w7rSbJ
-yiKeosoNbJl2kyj5dZjfBhWGgDLGDMM5w+Mh/5SrWgTL/QrhbB+lsrxILLznWqBi
-R8wJP0P2YW9fBahQskJQcUXt/3jsCsMTWea4rWc3HZGh03bAkJfLM+PDSOfTpvAZ
-6DQSp9QLzC9bgVNnq3W0SvOZGpF0xRa4InCyTUgxsNsV4+GIrmN5w4EbRFVVYu7D
-5OS5fxNSCukiS0fb6oQzUp0vIAycvvWHHbAy8T6UMoUor2nfvNcryiaOX5WBMLyh
-yMZ5gMOyXjdm1bT1XSlvtXPYUzxvsGAzTqS8mXjw8h7mm5htAgMBAAEwDQYJKoZI
-hvcNAQELBQADggEBAIs+T8Nkbl0gecT22CKW9/jMvUS1PGAyMqlwP8fNTsyv2xE9
-hLsyUrxsscuv+HGJu6Cz1R3hLI8YY5jEShmaelI0stlLahH9Fbm43EZuadGXOVKZ
-gMrNzQqLY5lec55rmS17GJlkm5opidkq4OlsCHfrBJitX6071atb0B1cdAjysWwV
-x40mnwq0TmYgBLDhWaM4/ZfZQRJQpPCtBJO06Nk7gTPiqJGJU5iEaz1PLvARq69o
-bJobSekf9tx3uwOIfioaoQvX0khkZ3ljFuNUpW3IE87OfPnYJQhu5xsTx00wi+Ce
-x64ghD4CzRa7wYsOjeb8cUUDMSj030NO9fBGVtA=
------END CERTIFICATE-----''';
-
-      final hash = calculateHashOfCertificate(certificate);
-      expect(hash, '247E5F7CF21DE14438EAE733E07AC5440593D0612570C7413674130608DF69A9');
-    });
-  });
-}

cli/Cargo.lock

@@ -1812,6 +1812,7 @@ dependencies = [
  "pem 3.0.6",
  "percent-encoding",
  "rand 0.9.5",
+ "rcgen 0.14.8",
  "reqwest",
  "rsa",
  "rustls",

cli/src/storage/identity.rs

@@ -86,20 +86,14 @@ impl Identity {
     }
 
     fn generate(alias: String, port: u16) -> anyhow::Result<Self> {
-        let key_pair = rcgen::KeyPair::generate()?;
-        let mut params = rcgen::CertificateParams::default();
-        params.distinguished_name = rcgen::DistinguishedName::new();
-        params
-            .distinguished_name
-            .push(rcgen::DnType::CommonName, "LocalSend User");
-        let cert = params.self_signed(&key_pair)?;
+        let cert = localsend::crypto::cert::generate_self_signed()?;
 
         Ok(Self {
             alias,
             port,
-            fingerprint: fingerprint_from_cert_der(cert.der()),
-            cert_pem: cert.pem(),
-            key_pem: key_pair.serialize_pem(),
+            fingerprint: cert.fingerprint,
+            cert_pem: cert.certificate_pem,
+            key_pem: cert.private_key_pem,
         })
     }
 

packages/core/Cargo.lock

@@ -190,6 +190,15 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "bit-vec"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b71798fca2c1fe1086445a7258a4bc81e6e49dcd24c8d0dd9a1e57395b603f51"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -549,7 +558,7 @@ dependencies = [
  "portable-atomic",
  "rand 0.9.2",
  "rand_core 0.6.4",
- "rcgen",
+ "rcgen 0.13.2",
  "ring",
  "rustls",
  "sec1",
@@ -1262,7 +1271,7 @@ dependencies = [
  "pem",
  "percent-encoding",
  "rand 0.9.2",
- "rcgen",
+ "rcgen 0.14.8",
  "reqwest",
  "rsa",
  "rustls",
@@ -1756,7 +1765,21 @@ dependencies = [
  "rustls-pki-types",
  "time",
  "x509-parser 0.16.0",
- "yasna",
+ "yasna 0.5.2",
+]
+
+[[package]]
+name = "rcgen"
+version = "0.14.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57f6d249aad744e274e682777a50283a225a32705394ee6d5fcc01efa25e4055"
+dependencies = [
+ "pem",
+ "ring",
+ "rustls-pki-types",
+ "time",
+ "x509-parser 0.18.0",
+ "yasna 0.6.0",
 ]
 
 [[package]]
@@ -2908,7 +2931,7 @@ dependencies = [
  "log",
  "portable-atomic",
  "rand 0.9.2",
- "rcgen",
+ "rcgen 0.13.2",
  "regex",
  "ring",
  "rtcp",
@@ -3418,6 +3441,16 @@ dependencies = [
  "time",
 ]
 
+[[package]]
+name = "yasna"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5f6765e852b9b4dc8e2a76843e4d64d1cea8e79bcde0b6901aea8e7c7f08282"
+dependencies = [
+ "bit-vec",
+ "time",
+]
+
 [[package]]
 name = "yoke"
 version = "0.8.1"

packages/core/Cargo.toml

@@ -18,6 +18,7 @@ hyper-util = { version = "0.1.19", features = ["server"], optional = true }
 lru = "0.16.3"
 pem = { version = "3.0.6", optional = true }
 percent-encoding = { version = "2.3", optional = true }
+rcgen = { version = "0.14", default-features = false, features = ["crypto", "pem", "ring"], optional = true }
 reqwest = { version = "0.13.1", features = ["charset", "http2", "system-proxy", "json", "rustls-no-provider", "stream", "webpki-roots"], default-features = false, optional = true }
 rand = "0.9.1"
 rsa = { version = "0.9.8", optional = true }
@@ -39,14 +40,19 @@ uuid = { version = "1.20.0", features = ["serde", "v4"] }
 webrtc = { version = "0.14.0", optional = true }
 x509-parser = { version = "0.18.0", features = ["verify"], optional = true }
 
-[dev-dependencies]
-rcgen = "0.13.2"
-
 [features]
 default = []
-crypto = ["ed25519-dalek", "rsa", "sha2", "tokio-util"]
+crypto = ["ed25519-dalek", "rcgen", "rsa", "sha2", "tokio-util"]
 http = ["crypto", "form_urlencoded", "http-body-util", "hyper", "hyper-util", "pem", "percent-encoding", "reqwest", "rustls", "socket2", "tokio-rustls", "tokio-util", "x509-parser"]
 multicast = ["if-addrs", "socket2", "tokio-util"]
 webrtc-signaling = ["tokio-tungstenite"]
 webrtc = ["crypto", "flate2", "dep:webrtc", "webrtc-signaling", "x509-parser"]
 full = ["crypto", "http", "multicast", "webrtc"]
+
+# RSA key generation is bignum-heavy and takes ~10x longer unoptimized;
+# keep the crypto crates optimized in dev so tests stay fast.
+[profile.dev.package.rsa]
+opt-level = 2
+
+[profile.dev.package.num-bigint-dig]
+opt-level = 2

packages/core/src/crypto/cert.rs

@@ -4,6 +4,57 @@ use x509_parser::certificate::X509Certificate;
 use x509_parser::pem::Pem;
 use x509_parser::x509::SubjectPublicKeyInfo;
 
+/// A freshly generated device identity: an RSA-2048 key pair and a
+/// self-signed certificate whose SHA-256 fingerprint identifies the device.
+pub struct SelfSignedCert {
+    /// The private key, PEM-encoded (PKCS#8).
+    pub private_key_pem: String,
+    /// The public key, PEM-encoded (SPKI).
+    pub public_key_pem: String,
+    /// The self-signed certificate, PEM-encoded.
+    pub certificate_pem: String,
+    /// The SHA-256 fingerprint of the certificate in DER format,
+    /// encoded as uppercase hex (see [fingerprint_from_cert_der]).
+    pub fingerprint: String,
+}
+
+/// Generates a new device identity, used for both the HTTP server and client
+/// certificates.
+///
+/// - RSA-2048, matching the certificates the Flutter app has historically
+///   generated in Dart.
+/// - `CN=LocalSend User` and no SANs: peers identify each other purely by the
+///   certificate fingerprint, so the name carries no information.
+/// - The serial number is derived from the hash of the public key
+///   (rcgen's default when no serial number is set).
+/// - Validity is rcgen's default (1975 to 4096), so certificates do not expire
+///   in practice and never need to be rotated for time reasons.
+pub fn generate_self_signed() -> anyhow::Result<SelfSignedCert> {
+    use rsa::pkcs8::{EncodePrivateKey, EncodePublicKey, LineEnding};
+
+    let mut rng = rsa::rand_core::OsRng;
+    let private_key = rsa::RsaPrivateKey::new(&mut rng, 2048)?;
+    let private_key_pem = private_key.to_pkcs8_pem(LineEnding::LF)?;
+    let public_key_pem = private_key
+        .to_public_key()
+        .to_public_key_pem(LineEnding::LF)?;
+
+    let key_pair = rcgen::KeyPair::try_from(private_key.to_pkcs8_der()?.as_bytes())?;
+    let mut params = rcgen::CertificateParams::default();
+    params.distinguished_name = rcgen::DistinguishedName::new();
+    params
+        .distinguished_name
+        .push(rcgen::DnType::CommonName, "LocalSend User");
+    let certificate = params.self_signed(&key_pair)?;
+
+    Ok(SelfSignedCert {
+        private_key_pem: private_key_pem.to_string(),
+        public_key_pem,
+        certificate_pem: certificate.pem(),
+        fingerprint: fingerprint_from_cert_der(certificate.der()),
+    })
+}
+
 pub fn verify_cert_from_pem(cert: String, public_key: Option<&str>) -> anyhow::Result<()> {
     let (cert_pem, _) = Pem::read(Cursor::new(cert.into_bytes()))?;
     let parsed_cert: X509Certificate = cert_pem.parse_x509()?;
@@ -188,6 +239,40 @@ nidU/qXQvBJ7NPUkXXgbcgqxK735iijOqQHmKts=
         );
     }
 
+    #[test]
+    fn test_generate_self_signed() {
+        let generated = generate_self_signed().unwrap();
+
+        assert!(generated
+            .private_key_pem
+            .starts_with("-----BEGIN PRIVATE KEY-----"));
+        assert!(generated
+            .public_key_pem
+            .starts_with("-----BEGIN PUBLIC KEY-----"));
+
+        // The certificate is self-consistent and carries the generated public key.
+        verify_cert_from_pem(
+            generated.certificate_pem.clone(),
+            Some(&generated.public_key_pem),
+        )
+        .unwrap();
+
+        // The fingerprint matches the DER bytes of the certificate.
+        let (cert_pem, _) =
+            Pem::read(Cursor::new(generated.certificate_pem.as_bytes().to_vec())).unwrap();
+        assert_eq!(
+            generated.fingerprint,
+            fingerprint_from_cert_der(&cert_pem.contents)
+        );
+
+        // The public key extracted from the certificate is the generated one.
+        let extracted = public_key_from_cert_der(&cert_pem.contents).unwrap();
+        assert_eq!(
+            extracted.replace("\r\n", "\n").trim(),
+            generated.public_key_pem.trim()
+        );
+    }
+
     #[test]
     fn test_fingerprint_from_cert_der() {
         let (cert_pem, _) = Pem::read(Cursor::new(CERT.as_bytes().to_vec())).unwrap();

packages/core/tests/v2_tls_pinning.rs

@@ -5,7 +5,6 @@
 
 use bytes::Bytes;
 use futures_util::StreamExt;
-use localsend::crypto::cert::fingerprint_from_cert_der;
 use localsend::http::client::{ClientError, LsHttpClientV2};
 use localsend::http::dto::ProtocolType;
 use localsend::http::dto_v2::{PrepareUploadRequestDtoV2, ProtocolTypeV2, RegisterDtoV2};
@@ -30,16 +29,12 @@ struct Identity {
 }
 
 fn generate_identity() -> Identity {
-    let key_pair = rcgen::KeyPair::generate().unwrap();
-    let cert = rcgen::CertificateParams::new(vec!["LocalSend User".to_string()])
-        .unwrap()
-        .self_signed(&key_pair)
-        .unwrap();
+    let cert = localsend::crypto::cert::generate_self_signed().unwrap();
 
     Identity {
-        cert: cert.pem(),
-        private_key: key_pair.serialize_pem(),
-        fingerprint: fingerprint_from_cert_der(cert.der()),
+        cert: cert.certificate_pem,
+        private_key: cert.private_key_pem,
+        fingerprint: cert.fingerprint,
     }
 }
 

packages/localsend_isolates/lib/rust/api/crypto.dart

@@ -12,6 +12,10 @@ Future<void> verifyCert({required String cert, required String publicKey}) =>
 
 Future<KeyPair> generateKeyPair() => RustLib.instance.api.crateApiCryptoGenerateKeyPair();
 
+/// Generates a new device identity: an RSA-2048 key pair and a self-signed
+/// certificate whose SHA-256 fingerprint identifies the device.
+Future<SecurityContext> generateSecurityContext() => RustLib.instance.api.crateApiCryptoGenerateSecurityContext();
+
 /// Computes the SHA-256 checksum of a file, encoded as lowercase hex.
 ///
 /// The file is read chunk by chunk, so it is never fully loaded into memory.
@@ -41,3 +45,30 @@ class KeyPair {
       identical(this, other) ||
       other is KeyPair && runtimeType == other.runtimeType && privateKey == other.privateKey && publicKey == other.publicKey;
 }
+
+class SecurityContext {
+  final String privateKey;
+  final String publicKey;
+  final String certificate;
+  final String certificateHash;
+
+  const SecurityContext({
+    required this.privateKey,
+    required this.publicKey,
+    required this.certificate,
+    required this.certificateHash,
+  });
+
+  @override
+  int get hashCode => privateKey.hashCode ^ publicKey.hashCode ^ certificate.hashCode ^ certificateHash.hashCode;
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is SecurityContext &&
+          runtimeType == other.runtimeType &&
+          privateKey == other.privateKey &&
+          publicKey == other.publicKey &&
+          certificate == other.certificate &&
+          certificateHash == other.certificateHash;
+}

packages/localsend_isolates/lib/rust/frb_generated.dart

@@ -74,7 +74,7 @@ class RustLib extends BaseEntrypoint<RustLibApi, RustLibApiImpl, RustLibWire> {
   String get codegenVersion => '2.12.0';
 
   @override
-  int get rustContentHash => 1795427439;
+  int get rustContentHash => -286605518;
 
   static const kDefaultExternalLibraryLoaderConfig = ExternalLibraryLoaderConfig(
     stem: 'rust_lib_localsend_app',
@@ -247,6 +247,8 @@ abstract class RustLibApi extends BaseApi {
 
   Future<KeyPair> crateApiCryptoGenerateKeyPair();
 
+  Future<SecurityContext> crateApiCryptoGenerateSecurityContext();
+
   Future<String> crateApiCryptoHashFile({String? path, int? fileDescriptor, Uint8List? bytes, required RsCancellationToken cancelToken});
 
   Future<RsMulticast> crateApiMulticastStartMulticast({
@@ -1670,6 +1672,30 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
     argNames: [],
   );
 
+  @override
+  Future<SecurityContext> crateApiCryptoGenerateSecurityContext() {
+    return handler.executeNormal(
+      NormalTask(
+        callFfi: (port_) {
+          final serializer = SseSerializer(generalizedFrbRustBinding);
+          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 45, port: port_);
+        },
+        codec: SseCodec(
+          decodeSuccessData: sse_decode_security_context,
+          decodeErrorData: sse_decode_AnyhowException,
+        ),
+        constMeta: kCrateApiCryptoGenerateSecurityContextConstMeta,
+        argValues: [],
+        apiImpl: this,
+      ),
+    );
+  }
+
+  TaskConstMeta get kCrateApiCryptoGenerateSecurityContextConstMeta => const TaskConstMeta(
+    debugName: 'generate_security_context',
+    argNames: [],
+  );
+
   @override
   Future<String> crateApiCryptoHashFile({String? path, int? fileDescriptor, Uint8List? bytes, required RsCancellationToken cancelToken}) {
     return handler.executeNormal(
@@ -1680,7 +1706,7 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
           sse_encode_opt_box_autoadd_i_32(fileDescriptor, serializer);
           sse_encode_opt_list_prim_u_8_strict(bytes, serializer);
           sse_encode_Auto_Ref_RustOpaque_flutter_rust_bridgefor_generatedRustAutoOpaqueInnerRsCancellationToken(cancelToken, serializer);
-          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 45, port: port_);
+          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 46, port: port_);
         },
         codec: SseCodec(
           decodeSuccessData: sse_decode_String,
@@ -1727,7 +1753,7 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
           sse_encode_String(fingerprint, serializer);
           sse_encode_protocol_type_v_2(protocol, serializer);
           sse_encode_bool(download, serializer);
-          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 46, port: port_);
+          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 47, port: port_);
         },
         codec: SseCodec(
           decodeSuccessData: sse_decode_Auto_Owned_RustOpaque_flutter_rust_bridgefor_generatedRustAutoOpaqueInnerRsMulticast,
@@ -1784,7 +1810,7 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
           sse_encode_opt_String(pin, serializer);
           sse_encode_opt_box_autoadd_web_send_params(webSend, serializer);
           sse_encode_opt_String(showToken, serializer);
-          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 47, port: port_);
+          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 48, port: port_);
         },
         codec: SseCodec(
           decodeSuccessData: sse_decode_Auto_Owned_RustOpaque_flutter_rust_bridgefor_generatedRustAutoOpaqueInnerRsHttpServer,
@@ -1810,7 +1836,7 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
           final serializer = SseSerializer(generalizedFrbRustBinding);
           sse_encode_String(cert, serializer);
           sse_encode_String(publicKey, serializer);
-          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 48, port: port_);
+          pdeCallFfi(generalizedFrbRustBinding, serializer, funcId: 49, port: port_);
         },
         codec: SseCodec(
           decodeSuccessData: sse_decode_unit,
@@ -2913,6 +2939,19 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
     }
   }
 
+  @protected
+  SecurityContext dco_decode_security_context(dynamic raw) {
+    // Codec=Dco (DartCObject based), see doc to use other codecs
+    final arr = raw as List<dynamic>;
+    if (arr.length != 4) throw Exception('unexpected arr length: expect 4 but see ${arr.length}');
+    return SecurityContext(
+      privateKey: dco_decode_String(arr[0]),
+      publicKey: dco_decode_String(arr[1]),
+      certificate: dco_decode_String(arr[2]),
+      certificateHash: dco_decode_String(arr[3]),
+    );
+  }
+
   @protected
   SessionEndReasonV2 dco_decode_session_end_reason_v_2(dynamic raw) {
     // Codec=Dco (DartCObject based), see doc to use other codecs
@@ -4126,6 +4165,16 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
     }
   }
 
+  @protected
+  SecurityContext sse_decode_security_context(SseDeserializer deserializer) {
+    // Codec=Sse (Serialization based), see doc to use other codecs
+    var var_privateKey = sse_decode_String(deserializer);
+    var var_publicKey = sse_decode_String(deserializer);
+    var var_certificate = sse_decode_String(deserializer);
+    var var_certificateHash = sse_decode_String(deserializer);
+    return SecurityContext(privateKey: var_privateKey, publicKey: var_publicKey, certificate: var_certificate, certificateHash: var_certificateHash);
+  }
+
   @protected
   SessionEndReasonV2 sse_decode_session_end_reason_v_2(SseDeserializer deserializer) {
     // Codec=Sse (Serialization based), see doc to use other codecs
@@ -5335,6 +5384,15 @@ class RustLibApiImpl extends RustLibApiImplPlatform implements RustLibApi {
     }
   }
 
+  @protected
+  void sse_encode_security_context(SecurityContext self, SseSerializer serializer) {
+    // Codec=Sse (Serialization based), see doc to use other codecs
+    sse_encode_String(self.privateKey, serializer);
+    sse_encode_String(self.publicKey, serializer);
+    sse_encode_String(self.certificate, serializer);
+    sse_encode_String(self.certificateHash, serializer);
+  }
+
   @protected
   void sse_encode_session_end_reason_v_2(SessionEndReasonV2 self, SseSerializer serializer) {
     // Codec=Sse (Serialization based), see doc to use other codecs

packages/localsend_isolates/lib/rust/frb_generated.io.dart

@@ -435,6 +435,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   RTCStatus dco_decode_rtc_status(dynamic raw);
 
+  @protected
+  SecurityContext dco_decode_security_context(dynamic raw);
+
   @protected
   SessionEndReasonV2 dco_decode_session_end_reason_v_2(dynamic raw);
 
@@ -865,6 +868,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   RTCStatus sse_decode_rtc_status(SseDeserializer deserializer);
 
+  @protected
+  SecurityContext sse_decode_security_context(SseDeserializer deserializer);
+
   @protected
   SessionEndReasonV2 sse_decode_session_end_reason_v_2(SseDeserializer deserializer);
 
@@ -1341,6 +1347,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   void sse_encode_rtc_status(RTCStatus self, SseSerializer serializer);
 
+  @protected
+  void sse_encode_security_context(SecurityContext self, SseSerializer serializer);
+
   @protected
   void sse_encode_session_end_reason_v_2(SessionEndReasonV2 self, SseSerializer serializer);
 

packages/localsend_isolates/lib/rust/frb_generated.web.dart

@@ -437,6 +437,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   RTCStatus dco_decode_rtc_status(dynamic raw);
 
+  @protected
+  SecurityContext dco_decode_security_context(dynamic raw);
+
   @protected
   SessionEndReasonV2 dco_decode_session_end_reason_v_2(dynamic raw);
 
@@ -867,6 +870,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   RTCStatus sse_decode_rtc_status(SseDeserializer deserializer);
 
+  @protected
+  SecurityContext sse_decode_security_context(SseDeserializer deserializer);
+
   @protected
   SessionEndReasonV2 sse_decode_session_end_reason_v_2(SseDeserializer deserializer);
 
@@ -1343,6 +1349,9 @@ abstract class RustLibApiImplPlatform extends BaseApiImpl<RustLibWire> {
   @protected
   void sse_encode_rtc_status(RTCStatus self, SseSerializer serializer);
 
+  @protected
+  void sse_encode_security_context(SecurityContext self, SseSerializer serializer);
+
   @protected
   void sse_encode_session_end_reason_v_2(SessionEndReasonV2 self, SseSerializer serializer);
 

packages/localsend_isolates/rust/Cargo.lock

@@ -255,6 +255,15 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "bit-vec"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b71798fca2c1fe1086445a7258a4bc81e6e49dcd24c8d0dd9a1e57395b603f51"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -666,7 +675,7 @@ dependencies = [
  "portable-atomic",
  "rand 0.9.5",
  "rand_core 0.6.4",
- "rcgen",
+ "rcgen 0.13.2",
  "ring",
  "rustls",
  "sec1",
@@ -1477,6 +1486,7 @@ dependencies = [
  "pem",
  "percent-encoding",
  "rand 0.9.5",
+ "rcgen 0.14.8",
  "reqwest",
  "rsa",
  "rustls",
@@ -2005,7 +2015,21 @@ dependencies = [
  "rustls-pki-types",
  "time",
  "x509-parser 0.16.0",
- "yasna",
+ "yasna 0.5.2",
+]
+
+[[package]]
+name = "rcgen"
+version = "0.14.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57f6d249aad744e274e682777a50283a225a32705394ee6d5fcc01efa25e4055"
+dependencies = [
+ "pem",
+ "ring",
+ "rustls-pki-types",
+ "time",
+ "x509-parser 0.18.1",
+ "yasna 0.6.0",
 ]
 
 [[package]]
@@ -3194,7 +3218,7 @@ dependencies = [
  "log",
  "portable-atomic",
  "rand 0.9.5",
- "rcgen",
+ "rcgen 0.13.2",
  "regex",
  "ring",
  "rtcp",
@@ -3630,6 +3654,16 @@ dependencies = [
  "time",
 ]
 
+[[package]]
+name = "yasna"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5f6765e852b9b4dc8e2a76843e4d64d1cea8e79bcde0b6901aea8e7c7f08282"
+dependencies = [
+ "bit-vec",
+ "time",
+]
+
 [[package]]
 name = "yoke"
 version = "0.8.3"

packages/localsend_isolates/rust/src/api/crypto.rs

@@ -20,6 +20,26 @@ pub struct KeyPair {
     pub public_key: String,
 }
 
+/// Generates a new device identity: an RSA-2048 key pair and a self-signed
+/// certificate whose SHA-256 fingerprint identifies the device.
+pub fn generate_security_context() -> anyhow::Result<SecurityContext> {
+    let cert = localsend::crypto::cert::generate_self_signed()?;
+
+    Ok(SecurityContext {
+        private_key: cert.private_key_pem,
+        public_key: cert.public_key_pem,
+        certificate: cert.certificate_pem,
+        certificate_hash: cert.fingerprint,
+    })
+}
+
+pub struct SecurityContext {
+    pub private_key: String,
+    pub public_key: String,
+    pub certificate: String,
+    pub certificate_hash: String,
+}
+
 /// Computes the SHA-256 checksum of a file, encoded as lowercase hex.
 ///
 /// The file is read chunk by chunk, so it is never fully loaded into memory.

packages/localsend_isolates/rust/src/frb_generated.rs

@@ -44,7 +44,7 @@ flutter_rust_bridge::frb_generated_boilerplate!(
     default_rust_auto_opaque = RustAutoOpaqueMoi,
 );
 pub(crate) const FLUTTER_RUST_BRIDGE_CODEGEN_VERSION: &str = "2.12.0";
-pub(crate) const FLUTTER_RUST_BRIDGE_CODEGEN_CONTENT_HASH: i32 = 1795427439;
+pub(crate) const FLUTTER_RUST_BRIDGE_CODEGEN_CONTENT_HASH: i32 = -286605518;
 
 // Section: executor
 
@@ -2638,6 +2638,40 @@ fn wire__crate__api__crypto__generate_key_pair_impl(
         },
     )
 }
+fn wire__crate__api__crypto__generate_security_context_impl(
+    port_: flutter_rust_bridge::for_generated::MessagePort,
+    ptr_: flutter_rust_bridge::for_generated::PlatformGeneralizedUint8ListPtr,
+    rust_vec_len_: i32,
+    data_len_: i32,
+) {
+    FLUTTER_RUST_BRIDGE_HANDLER.wrap_normal::<flutter_rust_bridge::for_generated::SseCodec, _, _>(
+        flutter_rust_bridge::for_generated::TaskInfo {
+            debug_name: "generate_security_context",
+            port: Some(port_),
+            mode: flutter_rust_bridge::for_generated::FfiCallMode::Normal,
+        },
+        move || {
+            let message = unsafe {
+                flutter_rust_bridge::for_generated::Dart2RustMessageSse::from_wire(
+                    ptr_,
+                    rust_vec_len_,
+                    data_len_,
+                )
+            };
+            let mut deserializer =
+                flutter_rust_bridge::for_generated::SseDeserializer::new(message);
+            deserializer.end();
+            move |context| {
+                transform_result_sse::<_, flutter_rust_bridge::for_generated::anyhow::Error>(
+                    (move || {
+                        let output_ok = crate::api::crypto::generate_security_context()?;
+                        Ok(output_ok)
+                    })(),
+                )
+            }
+        },
+    )
+}
 fn wire__crate__api__crypto__hash_file_impl(
     port_: flutter_rust_bridge::for_generated::MessagePort,
     ptr_: flutter_rust_bridge::for_generated::PlatformGeneralizedUint8ListPtr,
@@ -4262,6 +4296,22 @@ impl SseDecode for crate::api::webrtc::RTCStatus {
     }
 }
 
+impl SseDecode for crate::api::crypto::SecurityContext {
+    // Codec=Sse (Serialization based), see doc to use other codecs
+    fn sse_decode(deserializer: &mut flutter_rust_bridge::for_generated::SseDeserializer) -> Self {
+        let mut var_privateKey = <String>::sse_decode(deserializer);
+        let mut var_publicKey = <String>::sse_decode(deserializer);
+        let mut var_certificate = <String>::sse_decode(deserializer);
+        let mut var_certificateHash = <String>::sse_decode(deserializer);
+        return crate::api::crypto::SecurityContext {
+            private_key: var_privateKey,
+            public_key: var_publicKey,
+            certificate: var_certificate,
+            certificate_hash: var_certificateHash,
+        };
+    }
+}
+
 impl SseDecode for crate::api::server::SessionEndReasonV2 {
     // Codec=Sse (Serialization based), see doc to use other codecs
     fn sse_decode(deserializer: &mut flutter_rust_bridge::for_generated::SseDeserializer) -> Self {
@@ -4622,10 +4672,16 @@ fn pde_ffi_dispatcher_primary_impl(
             wire__crate__api__logging__enable_debug_logging_impl(port, ptr, rust_vec_len, data_len)
         }
         44 => wire__crate__api__crypto__generate_key_pair_impl(port, ptr, rust_vec_len, data_len),
-        45 => wire__crate__api__crypto__hash_file_impl(port, ptr, rust_vec_len, data_len),
-        46 => wire__crate__api__multicast__start_multicast_impl(port, ptr, rust_vec_len, data_len),
-        47 => wire__crate__api__server__start_server_impl(port, ptr, rust_vec_len, data_len),
-        48 => wire__crate__api__crypto__verify_cert_impl(port, ptr, rust_vec_len, data_len),
+        45 => wire__crate__api__crypto__generate_security_context_impl(
+            port,
+            ptr,
+            rust_vec_len,
+            data_len,
+        ),
+        46 => wire__crate__api__crypto__hash_file_impl(port, ptr, rust_vec_len, data_len),
+        47 => wire__crate__api__multicast__start_multicast_impl(port, ptr, rust_vec_len, data_len),
+        48 => wire__crate__api__server__start_server_impl(port, ptr, rust_vec_len, data_len),
+        49 => wire__crate__api__crypto__verify_cert_impl(port, ptr, rust_vec_len, data_len),
         _ => unreachable!(),
     }
 }
@@ -5516,6 +5572,29 @@ impl flutter_rust_bridge::IntoIntoDart<FrbWrapper<crate::api::webrtc::RTCStatus>
     }
 }
 // Codec=Dco (DartCObject based), see doc to use other codecs
+impl flutter_rust_bridge::IntoDart for crate::api::crypto::SecurityContext {
+    fn into_dart(self) -> flutter_rust_bridge::for_generated::DartAbi {
+        [
+            self.private_key.into_into_dart().into_dart(),
+            self.public_key.into_into_dart().into_dart(),
+            self.certificate.into_into_dart().into_dart(),
+            self.certificate_hash.into_into_dart().into_dart(),
+        ]
+        .into_dart()
+    }
+}
+impl flutter_rust_bridge::for_generated::IntoDartExceptPrimitive
+    for crate::api::crypto::SecurityContext
+{
+}
+impl flutter_rust_bridge::IntoIntoDart<crate::api::crypto::SecurityContext>
+    for crate::api::crypto::SecurityContext
+{
+    fn into_into_dart(self) -> crate::api::crypto::SecurityContext {
+        self
+    }
+}
+// Codec=Dco (DartCObject based), see doc to use other codecs
 impl flutter_rust_bridge::IntoDart for FrbWrapper<crate::api::server::SessionEndReasonV2> {
     fn into_dart(self) -> flutter_rust_bridge::for_generated::DartAbi {
         match self.0 {
@@ -6669,6 +6748,16 @@ impl SseEncode for crate::api::webrtc::RTCStatus {
     }
 }
 
+impl SseEncode for crate::api::crypto::SecurityContext {
+    // Codec=Sse (Serialization based), see doc to use other codecs
+    fn sse_encode(self, serializer: &mut flutter_rust_bridge::for_generated::SseSerializer) {
+        <String>::sse_encode(self.private_key, serializer);
+        <String>::sse_encode(self.public_key, serializer);
+        <String>::sse_encode(self.certificate, serializer);
+        <String>::sse_encode(self.certificate_hash, serializer);
+    }
+}
+
 impl SseEncode for crate::api::server::SessionEndReasonV2 {
     // Codec=Sse (Serialization based), see doc to use other codecs
     fn sse_encode(self, serializer: &mut flutter_rust_bridge::for_generated::SseSerializer) {