@@ -14,9 +14,12 @@
 #endif
 #include <algorithm>
 #include <array>
+#include <cctype>
 #include <climits>
 #include <cstring>
+#include <mutex>
 #include <string_view>
+#include <unordered_map>
 #if OPENSSL_VERSION_MAJOR >= 3
 #include <openssl/core_names.h>
 #include <openssl/params.h>
@@ -4482,11 +4485,52 @@ bool SSLCtxPointer::setCipherSuites(const char* ciphers) {
 // ============================================================================
 
 const Cipher Cipher::FromName(const char* name) {
-  return Cipher(EVP_get_cipherbyname(name));
+  if (const EVP_CIPHER* cipher = EVP_get_cipherbyname(name)) {
+    return Cipher(cipher);
+  }
+#if NCRYPTO_USE_OPENSSL3_PROVIDER
+  // Ciphers such as SM4-GCM only exist as fetchable provider algorithms.
+  // Cipher does not own what it points at, so the fetched reference is kept
+  // for the lifetime of the process instead of being freed.
+  MarkPopErrorOnReturn mark_pop_error_on_return;
+
+  static std::mutex fetched_mutex;
+  static auto& fetched_ciphers =
+      *new std::unordered_map<std::string, const EVP_CIPHER*>();
+
+  // A fetch is resolved against the library context's default properties,
+  // which setFipsEnabled() changes at runtime. Key on that state as well so
+  // that a cipher fetched before the switch cannot outlive it.
+  std::string key(EVP_default_properties_is_fips_enabled(nullptr) ? "fips:"
+                                                                  : "");
+  key.append(name);
+  std::transform(key.begin(), key.end(), key.begin(), [](unsigned char c) {
+    return static_cast<char>(std::tolower(c));
+  });
+
+  std::lock_guard<std::mutex> lock(fetched_mutex);
+  if (auto it = fetched_ciphers.find(key); it != fetched_ciphers.end()) {
+    return Cipher(it->second);
+  }
+  if (const EVP_CIPHER* fetched = EVP_CIPHER_fetch(nullptr, name, nullptr)) {
+    fetched_ciphers[key] = fetched;
+    return Cipher(fetched);
+  }
+#endif
+  return Cipher();
 }
 
 const Cipher Cipher::FromNid(int nid) {
-  return Cipher(EVP_get_cipherbynid(nid));
+  if (const EVP_CIPHER* cipher = EVP_get_cipherbynid(nid)) {
+    return Cipher(cipher);
+  }
+#if NCRYPTO_USE_OPENSSL3_PROVIDER
+  // May be a provider-only cipher; resolving by name falls back to a fetch.
+  if (const char* name = OBJ_nid2sn(nid)) {
+    return FromName(name);
+  }
+#endif
+  return Cipher();
 }
 
 const Cipher Cipher::FromCtx(const CipherCtxPointer& ctx) {
@@ -4572,7 +4616,18 @@ int Cipher::getBlockSize() const {
 
 int Cipher::getNid() const {
   if (!cipher_) return 0;
-  return EVP_CIPHER_nid(cipher_);
+  int nid = EVP_CIPHER_nid(cipher_);
+#if NCRYPTO_USE_OPENSSL3_PROVIDER
+  if (nid == NID_undef) {
+    // Provider-only ciphers inherit a nid from the legacy implementation they
+    // do not have, so recover it from the algorithm name.
+    if (const char* name = EVP_CIPHER_get0_name(cipher_)) {
+      nid = OBJ_sn2nid(name);
+      if (nid == NID_undef) nid = OBJ_ln2nid(name);
+    }
+  }
+#endif
+  return nid;
 }
 
 std::string_view Cipher::getModeLabel() const {
@@ -6240,6 +6295,22 @@ void Cipher::ForEach(Cipher::CipherNameCallback callback) {
       array_push_back<EVP_CIPHER>,
 #endif
       &context);
+
+#if NCRYPTO_USE_OPENSSL3_PROVIDER
+  // EVP_CIPHER_do_all_sorted() walks the legacy name table, so provider-only
+  // algorithms have to be probed for by name.
+  static constexpr const char* kProviderOnlyCiphers[] = {
+      "sm4-gcm",
+      "sm4-ccm",
+      "sm4-xts",
+  };
+  for (const char* name : kProviderOnlyCiphers) {
+    if (EVP_CIPHER* fetched = EVP_CIPHER_fetch(nullptr, name, nullptr)) {
+      EVP_CIPHER_free(fetched);
+      context.cb(name);
+    }
+  }
+#endif
 #endif
 }
 
 
@@ -0,0 +1,201 @@
+'use strict';
+const common = require('../common');
+if (!common.hasCrypto) common.skip('missing crypto');
+
+const { hasOpenSSL } = require('../common/crypto');
+const assert = require('assert');
+const crypto = require('crypto');
+
+// SM4-GCM and SM4-CCM are provider-only algorithms in OpenSSL 3.x (they
+// have no legacy EVP_CIPHER implementation) and are available in the
+// default provider since OpenSSL 3.1. SM4-XTS was added in OpenSSL 3.2.
+// Refs: https://github.com/nodejs/node/issues/64866
+if (!hasOpenSSL(3, 1)) common.skip('SM4 AEAD modes require OpenSSL >= 3.1');
+
+if (crypto.getFips()) common.skip('SM4 is not FIPS-approved');
+
+const ciphers = crypto.getCiphers();
+if (!ciphers.includes('sm4-cbc'))
+  common.skip('SM4 support is disabled in this build');
+
+// The provider-only SM4 modes must be reported by getCiphers().
+assert(ciphers.includes('sm4-gcm'));
+assert(ciphers.includes('sm4-ccm'));
+const hasSm4Xts = hasOpenSSL(3, 2);
+if (hasSm4Xts) assert(ciphers.includes('sm4-xts'));
+
+// getCipherInfo() must resolve provider-only ciphers, both by name and
+// by nid.
+{
+  const info = crypto.getCipherInfo('sm4-gcm');
+  assert(info);
+  assert.strictEqual(info.name, 'sm4-gcm');
+  assert.strictEqual(info.nid, 1248);
+  assert.strictEqual(info.mode, 'gcm');
+  assert.strictEqual(info.keyLength, 16);
+  assert.strictEqual(info.ivLength, 12);
+  assert.deepStrictEqual(crypto.getCipherInfo(info.nid), info);
+}
+
+{
+  const info = crypto.getCipherInfo('sm4-ccm');
+  assert(info);
+  assert.strictEqual(info.name, 'sm4-ccm');
+  assert.strictEqual(info.nid, 1249);
+  assert.strictEqual(info.mode, 'ccm');
+  assert.strictEqual(info.keyLength, 16);
+  assert.strictEqual(info.ivLength, 12);
+  assert.deepStrictEqual(crypto.getCipherInfo(info.nid), info);
+}
+
+if (hasSm4Xts) {
+  const info = crypto.getCipherInfo('sm4-xts');
+  assert(info);
+  assert.strictEqual(info.name, 'sm4-xts');
+  assert.strictEqual(info.nid, 1290);
+  assert.strictEqual(info.mode, 'xts');
+  assert.strictEqual(info.keyLength, 32);
+  assert.deepStrictEqual(crypto.getCipherInfo(info.nid), info);
+}
+
+// Test vectors from RFC 8998, appendix A.
+const kKey = Buffer.from('0123456789ABCDEFFEDCBA9876543210', 'hex');
+const kIv = Buffer.from('00001234567800000000ABCD', 'hex');
+const kAad = Buffer.from('FEEDFACEDEADBEEFFEEDFACEDEADBEEFABADDAD2', 'hex');
+const kPlaintext = Buffer.from(
+  'AAAAAAAAAAAAAAAABBBBBBBBBBBBBBBB' +
+    'CCCCCCCCCCCCCCCCDDDDDDDDDDDDDDDD' +
+    'EEEEEEEEEEEEEEEEFFFFFFFFFFFFFFFF' +
+    'EEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAA',
+  'hex',
+);
+
+// RFC 8998, appendix A.1.
+{
+  const kCiphertext = Buffer.from(
+    '17F399F08C67D5EE19D0DC9969C4BB7D' +
+      '5FD46FD3756489069157B282BB200735' +
+      'D82710CA5C22F0CCFA7CBF93D496AC15' +
+      'A56834CBCF98C397B4024A2691233B8D',
+    'hex',
+  );
+  const kAuthTag = Buffer.from('83DE3541E4C2B58177E065A9BF7B62EC', 'hex');
+
+  const cipher = crypto.createCipheriv('sm4-gcm', kKey, kIv);
+  cipher.setAAD(kAad);
+  const ciphertext = Buffer.concat([cipher.update(kPlaintext), cipher.final()]);
+  assert.deepStrictEqual(ciphertext, kCiphertext);
+  assert.deepStrictEqual(cipher.getAuthTag(), kAuthTag);
+
+  const decipher = crypto.createDecipheriv('sm4-gcm', kKey, kIv);
+  decipher.setAAD(kAad);
+  decipher.setAuthTag(kAuthTag);
+  const plaintext = Buffer.concat([
+    decipher.update(kCiphertext),
+    decipher.final(),
+  ]);
+  assert.deepStrictEqual(plaintext, kPlaintext);
+
+  // A tampered authentication tag must be rejected.
+  const badTag = Buffer.from(kAuthTag);
+  badTag[0] ^= 1;
+  const failing = crypto.createDecipheriv('sm4-gcm', kKey, kIv);
+  failing.setAAD(kAad);
+  failing.setAuthTag(badTag);
+  failing.update(kCiphertext);
+  assert.throws(() => failing.final(), {
+    message: /Unsupported state or unable to authenticate data/,
+  });
+}
+
+// RFC 8998, appendix A.2.
+{
+  const kCiphertext = Buffer.from(
+    '48AF93501FA62ADBCD414CCE6034D895' +
+      'DDA1BF8F132F042098661572E7483094' +
+      'FD12E518CE062C98ACEE28D95DF4416B' +
+      'ED31A2F04476C18BB40C84A74B97DC5B',
+    'hex',
+  );
+  const kAuthTag = Buffer.from('16842D4FA186F56AB33256971FA110F4', 'hex');
+
+  const cipher = crypto.createCipheriv('sm4-ccm', kKey, kIv, {
+    authTagLength: 16,
+  });
+  cipher.setAAD(kAad, { plaintextLength: kPlaintext.length });
+  const ciphertext = Buffer.concat([cipher.update(kPlaintext), cipher.final()]);
+  assert.deepStrictEqual(ciphertext, kCiphertext);
+  assert.deepStrictEqual(cipher.getAuthTag(), kAuthTag);
+
+  const decipher = crypto.createDecipheriv('sm4-ccm', kKey, kIv, {
+    authTagLength: 16,
+  });
+  decipher.setAuthTag(kAuthTag);
+  decipher.setAAD(kAad, { plaintextLength: kCiphertext.length });
+  const plaintext = Buffer.concat([
+    decipher.update(kCiphertext),
+    decipher.final(),
+  ]);
+  assert.deepStrictEqual(plaintext, kPlaintext);
+}
+
+// There are no official SM4-XTS test vectors; do a round-trip instead.
+if (hasSm4Xts) {
+  const key = Buffer.from(
+    '00112233445566778899AABBCCDDEEFFFFEEDDCCBBAA99887766554433221100',
+    'hex',
+  );
+  const iv = Buffer.from('000102030405060708090A0B0C0D0E0F', 'hex');
+
+  const cipher = crypto.createCipheriv('sm4-xts', key, iv);
+  const ciphertext = Buffer.concat([cipher.update(kPlaintext), cipher.final()]);
+  assert.strictEqual(ciphertext.length, kPlaintext.length);
+  assert.notDeepStrictEqual(ciphertext, kPlaintext);
+
+  const decipher = crypto.createDecipheriv('sm4-xts', key, iv);
+  const plaintext = Buffer.concat([
+    decipher.update(ciphertext),
+    decipher.final(),
+  ]);
+  assert.deepStrictEqual(plaintext, kPlaintext);
+}
+
+// Cipher name lookup is case-insensitive, including for fetched
+// provider-only ciphers.
+{
+  const cipher = crypto.createCipheriv('SM4-GCM', kKey, kIv);
+  cipher.setAAD(kAad);
+  cipher.update(kPlaintext);
+  cipher.final();
+}
+
+// The EVP_CIPHER_fetch() fallback must not make unknown algorithms resolve.
+{
+  const unknown = 'sm4-gcm-not-a-real-cipher';
+
+  // Repeated, so that a failed lookup is not cached as a success.
+  for (let i = 0; i < 2; i++) {
+    assert.strictEqual(crypto.getCipherInfo(unknown), undefined);
+    assert.throws(() => crypto.createCipheriv(unknown, kKey, kIv), {
+      code: 'ERR_CRYPTO_UNKNOWN_CIPHER',
+      message: 'Unknown cipher',
+    });
+  }
+
+  // Unknown names must not leave anything behind on the OpenSSL error queue
+  // for the next operation to trip over.
+  const cipher = crypto.createCipheriv('sm4-gcm', kKey, kIv);
+  cipher.setAAD(kAad);
+  assert.strictEqual(
+    Buffer.concat([cipher.update(kPlaintext), cipher.final()]).length,
+    kPlaintext.length,
+  );
+}
+
+// Cipher::FromNid() now falls back to a name lookup. A nid that is a valid
+// object identifier but not a cipher must still resolve to nothing.
+{
+  assert.strictEqual(crypto.getCipherInfo(672), undefined); // NID_sha256
+  assert.strictEqual(crypto.getCipherInfo(0), undefined); // NID_undef
+  assert.strictEqual(crypto.getCipherInfo(-1), undefined);
+}
@@ -0,0 +1,48 @@
+// Flags: --expose-internals
+'use strict';
+const common = require('../common');
+if (!common.hasCrypto) common.skip('missing crypto');
+
+if (process.features.openssl_is_boringssl)
+  common.skip('BoringSSL does not support FIPS');
+
+const { internalBinding } = require('internal/test/binding');
+const { testFipsCrypto } = internalBinding('crypto');
+if (!testFipsCrypto()) common.skip('no FIPS provider available');
+
+const assert = require('assert');
+const crypto = require('crypto');
+
+// Also covers --force-fips, which makes setFips() throw.
+if (crypto.getFips()) common.skip('FIPS is already enabled');
+
+if (!crypto.getCiphers().includes('sm4-cbc'))
+  common.skip('SM4 support is disabled in this build');
+
+// Provider-only ciphers are fetched once and cached. Enabling FIPS changes the
+// default properties every fetch is resolved against, so the cached instance
+// must not survive the switch: SM4 is not FIPS-approved.
+// Refs: https://github.com/nodejs/node/issues/64866
+
+const key = Buffer.alloc(16);
+const iv = Buffer.alloc(12);
+
+// Populate the cache while FIPS is still disabled.
+assert(crypto.getCiphers().includes('sm4-gcm'));
+crypto.createCipheriv('sm4-gcm', key, iv);
+
+crypto.setFips(true);
+assert.strictEqual(crypto.getFips(), 1);
+
+assert(!crypto.getCiphers().includes('sm4-gcm'));
+assert.strictEqual(crypto.getCipherInfo('sm4-gcm'), undefined);
+assert.throws(() => crypto.createCipheriv('sm4-gcm', key, iv), {
+  code: 'ERR_CRYPTO_UNKNOWN_CIPHER',
+});
+
+// Disabling FIPS again must make it available once more.
+crypto.setFips(false);
+assert.strictEqual(crypto.getFips(), 0);
+
+assert(crypto.getCiphers().includes('sm4-gcm'));
+crypto.createCipheriv('sm4-gcm', key, iv);