Adding upstream version 3.2.6.upstream/3.2.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 2412 insertions, 0 deletions

diff --git a/src/contrib/libngtcp2/ngtcp2/crypto/gnutls.c b/src/contrib/libngtcp2/ngtcp2/crypto/gnutls.c
new file mode 100644
index 0000000..73ea0c1
--- /dev/null
+++ b/src/contrib/libngtcp2/ngtcp2/crypto/gnutls.c
@@ -0,0 +1,644 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2020 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <assert.h>
+
+#include <ngtcp2/ngtcp2_crypto.h>
+#include <ngtcp2/ngtcp2_crypto_gnutls.h>
+
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
+#include <string.h>
+
+#include "shared.h"
+
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_aes_128_gcm(ngtcp2_crypto_aead *aead) {
+  return ngtcp2_crypto_aead_init(aead, (void *)GNUTLS_CIPHER_AES_128_GCM);
+}
+
+ngtcp2_crypto_md *ngtcp2_crypto_md_sha256(ngtcp2_crypto_md *md) {
+  md->native_handle = (void *)GNUTLS_DIG_SHA256;
+  return md;
+}
+
+ngtcp2_crypto_ctx *ngtcp2_crypto_ctx_initial(ngtcp2_crypto_ctx *ctx) {
+  ngtcp2_crypto_aead_init(&ctx->aead, (void *)GNUTLS_CIPHER_AES_128_GCM);
+  ctx->md.native_handle = (void *)GNUTLS_DIG_SHA256;
+  ctx->hp.native_handle = (void *)GNUTLS_CIPHER_AES_128_CBC;
+  ctx->max_encryption = 0;
+  ctx->max_decryption_failure = 0;
+  return ctx;
+}
+
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_init(ngtcp2_crypto_aead *aead,
+                                            void *aead_native_handle) {
+  aead->native_handle = aead_native_handle;
+  aead->max_overhead = gnutls_cipher_get_tag_size(
+      (gnutls_cipher_algorithm_t)(intptr_t)aead_native_handle);
+  return aead;
+}
+
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_retry(ngtcp2_crypto_aead *aead) {
+  return ngtcp2_crypto_aead_init(aead, (void *)GNUTLS_CIPHER_AES_128_GCM);
+}
+
+static gnutls_cipher_algorithm_t
+crypto_get_hp(gnutls_cipher_algorithm_t cipher) {
+  switch (cipher) {
+  case GNUTLS_CIPHER_AES_128_GCM:
+  case GNUTLS_CIPHER_AES_128_CCM:
+    return GNUTLS_CIPHER_AES_128_CBC;
+  case GNUTLS_CIPHER_AES_256_GCM:
+  case GNUTLS_CIPHER_AES_256_CCM:
+    return GNUTLS_CIPHER_AES_256_CBC;
+  case GNUTLS_CIPHER_CHACHA20_POLY1305:
+    return GNUTLS_CIPHER_CHACHA20_32;
+  default:
+    return GNUTLS_CIPHER_UNKNOWN;
+  }
+}
+
+static uint64_t
+crypto_get_aead_max_encryption(gnutls_cipher_algorithm_t cipher) {
+  switch (cipher) {
+  case GNUTLS_CIPHER_AES_128_GCM:
+  case GNUTLS_CIPHER_AES_256_GCM:
+    return NGTCP2_CRYPTO_MAX_ENCRYPTION_AES_GCM;
+  case GNUTLS_CIPHER_CHACHA20_POLY1305:
+    return NGTCP2_CRYPTO_MAX_ENCRYPTION_CHACHA20_POLY1305;
+  case GNUTLS_CIPHER_AES_128_CCM:
+  case GNUTLS_CIPHER_AES_256_CCM:
+    return NGTCP2_CRYPTO_MAX_ENCRYPTION_AES_CCM;
+  default:
+    return 0;
+  }
+}
+
+static uint64_t
+crypto_get_aead_max_decryption_failure(gnutls_cipher_algorithm_t cipher) {
+  switch (cipher) {
+  case GNUTLS_CIPHER_AES_128_GCM:
+  case GNUTLS_CIPHER_AES_256_GCM:
+    return NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_AES_GCM;
+  case GNUTLS_CIPHER_CHACHA20_POLY1305:
+    return NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_CHACHA20_POLY1305;
+  case GNUTLS_CIPHER_AES_128_CCM:
+  case GNUTLS_CIPHER_AES_256_CCM:
+    return NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_AES_CCM;
+  default:
+    return 0;
+  }
+}
+
+ngtcp2_crypto_ctx *ngtcp2_crypto_ctx_tls(ngtcp2_crypto_ctx *ctx,
+                                         void *tls_native_handle) {
+  gnutls_session_t session = tls_native_handle;
+  gnutls_cipher_algorithm_t cipher;
+  gnutls_digest_algorithm_t hash;
+  gnutls_cipher_algorithm_t hp_cipher;
+
+  cipher = gnutls_cipher_get(session);
+  if (cipher != GNUTLS_CIPHER_UNKNOWN && cipher != GNUTLS_CIPHER_NULL) {
+    ngtcp2_crypto_aead_init(&ctx->aead, (void *)cipher);
+  }
+
+  hash = gnutls_prf_hash_get(session);
+  if (hash != GNUTLS_DIG_UNKNOWN && hash != GNUTLS_DIG_NULL) {
+    ctx->md.native_handle = (void *)hash;
+  }
+
+  hp_cipher = crypto_get_hp(cipher);
+  if (hp_cipher != GNUTLS_CIPHER_UNKNOWN) {
+    ctx->hp.native_handle = (void *)hp_cipher;
+  }
+
+  ctx->max_encryption = crypto_get_aead_max_encryption(cipher);
+  ctx->max_decryption_failure = crypto_get_aead_max_decryption_failure(cipher);
+
+  return ctx;
+}
+
+ngtcp2_crypto_ctx *ngtcp2_crypto_ctx_tls_early(ngtcp2_crypto_ctx *ctx,
+                                               void *tls_native_handle) {
+  gnutls_session_t session = tls_native_handle;
+  gnutls_cipher_algorithm_t cipher;
+  gnutls_digest_algorithm_t hash;
+  gnutls_cipher_algorithm_t hp_cipher;
+
+  cipher = gnutls_early_cipher_get(session);
+  if (cipher != GNUTLS_CIPHER_UNKNOWN && cipher != GNUTLS_CIPHER_NULL) {
+    ngtcp2_crypto_aead_init(&ctx->aead, (void *)cipher);
+  }
+
+  hash = gnutls_early_prf_hash_get(session);
+  if (hash != GNUTLS_DIG_UNKNOWN && hash != GNUTLS_DIG_NULL) {
+    ctx->md.native_handle = (void *)hash;
+  }
+
+  hp_cipher = crypto_get_hp(cipher);
+  if (hp_cipher != GNUTLS_CIPHER_UNKNOWN) {
+    ctx->hp.native_handle = (void *)hp_cipher;
+  }
+
+  ctx->max_encryption = crypto_get_aead_max_encryption(cipher);
+  ctx->max_decryption_failure = crypto_get_aead_max_decryption_failure(cipher);
+
+  return ctx;
+}
+
+size_t ngtcp2_crypto_md_hashlen(const ngtcp2_crypto_md *md) {
+  return gnutls_hash_get_len(
+      (gnutls_digest_algorithm_t)(intptr_t)md->native_handle);
+}
+
+size_t ngtcp2_crypto_aead_keylen(const ngtcp2_crypto_aead *aead) {
+  return gnutls_cipher_get_key_size(
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle);
+}
+
+size_t ngtcp2_crypto_aead_noncelen(const ngtcp2_crypto_aead *aead) {
+  return gnutls_cipher_get_iv_size(
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle);
+}
+
+int ngtcp2_crypto_aead_ctx_encrypt_init(ngtcp2_crypto_aead_ctx *aead_ctx,
+                                        const ngtcp2_crypto_aead *aead,
+                                        const uint8_t *key, size_t noncelen) {
+  gnutls_cipher_algorithm_t cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle;
+  gnutls_aead_cipher_hd_t hd;
+  gnutls_datum_t _key;
+
+  (void)noncelen;
+
+  _key.data = (void *)key;
+  _key.size = (unsigned int)ngtcp2_crypto_aead_keylen(aead);
+
+  if (gnutls_aead_cipher_init(&hd, cipher, &_key) != 0) {
+    return -1;
+  }
+
+  aead_ctx->native_handle = hd;
+
+  return 0;
+}
+
+int ngtcp2_crypto_aead_ctx_decrypt_init(ngtcp2_crypto_aead_ctx *aead_ctx,
+                                        const ngtcp2_crypto_aead *aead,
+                                        const uint8_t *key, size_t noncelen) {
+  gnutls_cipher_algorithm_t cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle;
+  gnutls_aead_cipher_hd_t hd;
+  gnutls_datum_t _key;
+
+  (void)noncelen;
+
+  _key.data = (void *)key;
+  _key.size = (unsigned int)ngtcp2_crypto_aead_keylen(aead);
+
+  if (gnutls_aead_cipher_init(&hd, cipher, &_key) != 0) {
+    return -1;
+  }
+
+  aead_ctx->native_handle = hd;
+
+  return 0;
+}
+
+void ngtcp2_crypto_aead_ctx_free(ngtcp2_crypto_aead_ctx *aead_ctx) {
+  if (aead_ctx->native_handle) {
+    gnutls_aead_cipher_deinit(aead_ctx->native_handle);
+  }
+}
+
+int ngtcp2_crypto_cipher_ctx_encrypt_init(ngtcp2_crypto_cipher_ctx *cipher_ctx,
+                                          const ngtcp2_crypto_cipher *cipher,
+                                          const uint8_t *key) {
+  gnutls_cipher_algorithm_t _cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)cipher->native_handle;
+  gnutls_cipher_hd_t hd;
+  gnutls_datum_t _key;
+
+  _key.data = (void *)key;
+  _key.size = (unsigned int)gnutls_cipher_get_key_size(_cipher);
+
+  if (gnutls_cipher_init(&hd, _cipher, &_key, NULL) != 0) {
+    return -1;
+  }
+
+  cipher_ctx->native_handle = hd;
+
+  return 0;
+}
+
+void ngtcp2_crypto_cipher_ctx_free(ngtcp2_crypto_cipher_ctx *cipher_ctx) {
+  if (cipher_ctx->native_handle) {
+    gnutls_cipher_deinit(cipher_ctx->native_handle);
+  }
+}
+
+int ngtcp2_crypto_hkdf_extract(uint8_t *dest, const ngtcp2_crypto_md *md,
+                               const uint8_t *secret, size_t secretlen,
+                               const uint8_t *salt, size_t saltlen) {
+  gnutls_mac_algorithm_t prf =
+      (gnutls_mac_algorithm_t)(intptr_t)md->native_handle;
+  gnutls_datum_t _secret = {(void *)secret, (unsigned int)secretlen};
+  gnutls_datum_t _salt = {(void *)salt, (unsigned int)saltlen};
+
+  if (gnutls_hkdf_extract(prf, &_secret, &_salt, dest) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_hkdf_expand(uint8_t *dest, size_t destlen,
+                              const ngtcp2_crypto_md *md, const uint8_t *secret,
+                              size_t secretlen, const uint8_t *info,
+                              size_t infolen) {
+  gnutls_mac_algorithm_t prf =
+      (gnutls_mac_algorithm_t)(intptr_t)md->native_handle;
+  gnutls_datum_t _secret = {(void *)secret, (unsigned int)secretlen};
+  gnutls_datum_t _info = {(void *)info, (unsigned int)infolen};
+
+  if (gnutls_hkdf_expand(prf, &_secret, &_info, dest, destlen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_hkdf(uint8_t *dest, size_t destlen,
+                       const ngtcp2_crypto_md *md, const uint8_t *secret,
+                       size_t secretlen, const uint8_t *salt, size_t saltlen,
+                       const uint8_t *info, size_t infolen) {
+  gnutls_mac_algorithm_t prf =
+      (gnutls_mac_algorithm_t)(intptr_t)md->native_handle;
+  size_t keylen = ngtcp2_crypto_md_hashlen(md);
+  uint8_t key[64];
+  gnutls_datum_t _secret = {(void *)secret, (unsigned int)secretlen};
+  gnutls_datum_t _key = {(void *)key, (unsigned int)keylen};
+  gnutls_datum_t _salt = {(void *)salt, (unsigned int)saltlen};
+  gnutls_datum_t _info = {(void *)info, (unsigned int)infolen};
+
+  assert(keylen <= sizeof(key));
+
+  if (gnutls_hkdf_extract(prf, &_secret, &_salt, key) != 0) {
+    return -1;
+  }
+
+  if (gnutls_hkdf_expand(prf, &_key, &_info, dest, destlen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_encrypt(uint8_t *dest, const ngtcp2_crypto_aead *aead,
+                          const ngtcp2_crypto_aead_ctx *aead_ctx,
+                          const uint8_t *plaintext, size_t plaintextlen,
+                          const uint8_t *nonce, size_t noncelen,
+                          const uint8_t *aad, size_t aadlen) {
+  gnutls_cipher_algorithm_t cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle;
+  gnutls_aead_cipher_hd_t hd = aead_ctx->native_handle;
+  size_t taglen = gnutls_cipher_get_tag_size(cipher);
+  size_t ciphertextlen = plaintextlen + taglen;
+
+  if (gnutls_aead_cipher_encrypt(hd, nonce, noncelen, aad, aadlen, taglen,
+                                 plaintext, plaintextlen, dest,
+                                 &ciphertextlen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_decrypt(uint8_t *dest, const ngtcp2_crypto_aead *aead,
+                          const ngtcp2_crypto_aead_ctx *aead_ctx,
+                          const uint8_t *ciphertext, size_t ciphertextlen,
+                          const uint8_t *nonce, size_t noncelen,
+                          const uint8_t *aad, size_t aadlen) {
+  gnutls_cipher_algorithm_t cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)aead->native_handle;
+  gnutls_aead_cipher_hd_t hd = aead_ctx->native_handle;
+  size_t taglen = gnutls_cipher_get_tag_size(cipher);
+  size_t plaintextlen;
+
+  if (taglen > ciphertextlen) {
+    return -1;
+  }
+
+  plaintextlen = ciphertextlen - taglen;
+
+  if (gnutls_aead_cipher_decrypt(hd, nonce, noncelen, aad, aadlen, taglen,
+                                 ciphertext, ciphertextlen, dest,
+                                 &plaintextlen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_hp_mask(uint8_t *dest, const ngtcp2_crypto_cipher *hp,
+                          const ngtcp2_crypto_cipher_ctx *hp_ctx,
+                          const uint8_t *sample) {
+  gnutls_cipher_algorithm_t cipher =
+      (gnutls_cipher_algorithm_t)(intptr_t)hp->native_handle;
+  gnutls_cipher_hd_t hd = hp_ctx->native_handle;
+
+  switch (cipher) {
+  case GNUTLS_CIPHER_AES_128_CBC:
+  case GNUTLS_CIPHER_AES_256_CBC: {
+    uint8_t iv[16];
+    uint8_t buf[16];
+
+    /* Emulate one block AES-ECB by invalidating the effect of IV */
+    memset(iv, 0, sizeof(iv));
+
+    gnutls_cipher_set_iv(hd, iv, sizeof(iv));
+
+    if (gnutls_cipher_encrypt2(hd, sample, 16, buf, sizeof(buf)) != 0) {
+      return -1;
+    }
+
+    memcpy(dest, buf, 5);
+  } break;
+
+  case GNUTLS_CIPHER_CHACHA20_32: {
+    static const uint8_t PLAINTEXT[] = "\x00\x00\x00\x00\x00";
+    uint8_t buf[5 + 16];
+    size_t buflen = sizeof(buf);
+
+    gnutls_cipher_set_iv(hd, (void *)sample, 16);
+
+    if (gnutls_cipher_encrypt2(hd, PLAINTEXT, sizeof(PLAINTEXT) - 1, buf,
+                               buflen) != 0) {
+      return -1;
+    }
+
+    memcpy(dest, buf, 5);
+  } break;
+  default:
+    assert(0);
+  }
+
+  return 0;
+}
+
+ngtcp2_crypto_level ngtcp2_crypto_gnutls_from_gnutls_record_encryption_level(
+    gnutls_record_encryption_level_t gtls_level) {
+  switch (gtls_level) {
+  case GNUTLS_ENCRYPTION_LEVEL_INITIAL:
+    return NGTCP2_CRYPTO_LEVEL_INITIAL;
+  case GNUTLS_ENCRYPTION_LEVEL_HANDSHAKE:
+    return NGTCP2_CRYPTO_LEVEL_HANDSHAKE;
+  case GNUTLS_ENCRYPTION_LEVEL_APPLICATION:
+    return NGTCP2_CRYPTO_LEVEL_APPLICATION;
+  case GNUTLS_ENCRYPTION_LEVEL_EARLY:
+    return NGTCP2_CRYPTO_LEVEL_EARLY;
+  default:
+    assert(0);
+    abort();
+  }
+}
+
+gnutls_record_encryption_level_t
+ngtcp2_crypto_gnutls_from_ngtcp2_level(ngtcp2_crypto_level crypto_level) {
+  switch (crypto_level) {
+  case NGTCP2_CRYPTO_LEVEL_INITIAL:
+    return GNUTLS_ENCRYPTION_LEVEL_INITIAL;
+  case NGTCP2_CRYPTO_LEVEL_HANDSHAKE:
+    return GNUTLS_ENCRYPTION_LEVEL_HANDSHAKE;
+  case NGTCP2_CRYPTO_LEVEL_APPLICATION:
+    return GNUTLS_ENCRYPTION_LEVEL_APPLICATION;
+  case NGTCP2_CRYPTO_LEVEL_EARLY:
+    return GNUTLS_ENCRYPTION_LEVEL_EARLY;
+  default:
+    assert(0);
+    abort();
+  }
+}
+
+int ngtcp2_crypto_read_write_crypto_data(ngtcp2_conn *conn,
+                                         ngtcp2_crypto_level crypto_level,
+                                         const uint8_t *data, size_t datalen) {
+  gnutls_session_t session = ngtcp2_conn_get_tls_native_handle(conn);
+  int rv;
+
+  if (datalen > 0) {
+    rv = gnutls_handshake_write(
+        session, ngtcp2_crypto_gnutls_from_ngtcp2_level(crypto_level), data,
+        datalen);
+    if (rv != 0) {
+      if (!gnutls_error_is_fatal(rv)) {
+        return 0;
+      }
+      gnutls_alert_send_appropriate(session, rv);
+      return -1;
+    }
+  }
+
+  if (!ngtcp2_conn_get_handshake_completed(conn)) {
+    rv = gnutls_handshake(session);
+    if (rv < 0) {
+      if (!gnutls_error_is_fatal(rv)) {
+        return 0;
+      }
+      gnutls_alert_send_appropriate(session, rv);
+      return -1;
+    }
+
+    ngtcp2_conn_handshake_completed(conn);
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_set_remote_transport_params(ngtcp2_conn *conn, void *tls) {
+  (void)conn;
+  (void)tls;
+  /* Nothing to do; GnuTLS applications are supposed to register the
+     quic_transport_parameters extension with
+     gnutls_session_ext_register. */
+  return 0;
+}
+
+int ngtcp2_crypto_set_local_transport_params(void *tls, const uint8_t *buf,
+                                             size_t len) {
+  (void)tls;
+  (void)buf;
+  (void)len;
+  /* Nothing to do; GnuTLS applications are supposed to register the
+     quic_transport_parameters extension with
+     gnutls_session_ext_register. */
+  return 0;
+}
+
+int ngtcp2_crypto_get_path_challenge_data_cb(ngtcp2_conn *conn, uint8_t *data,
+                                             void *user_data) {
+  (void)conn;
+  (void)user_data;
+
+  if (gnutls_rnd(GNUTLS_RND_RANDOM, data, NGTCP2_PATH_CHALLENGE_DATALEN) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_random(uint8_t *data, size_t datalen) {
+  if (gnutls_rnd(GNUTLS_RND_RANDOM, data, datalen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+static int secret_func(gnutls_session_t session,
+                       gnutls_record_encryption_level_t gtls_level,
+                       const void *rx_secret, const void *tx_secret,
+                       size_t secretlen) {
+  ngtcp2_crypto_conn_ref *conn_ref = gnutls_session_get_ptr(session);
+  ngtcp2_conn *conn = conn_ref->get_conn(conn_ref);
+  ngtcp2_crypto_level level =
+      ngtcp2_crypto_gnutls_from_gnutls_record_encryption_level(gtls_level);
+
+  if (rx_secret &&
+      ngtcp2_crypto_derive_and_install_rx_key(conn, NULL, NULL, NULL, level,
+                                              rx_secret, secretlen) != 0) {
+    return -1;
+  }
+
+  if (tx_secret &&
+      ngtcp2_crypto_derive_and_install_tx_key(conn, NULL, NULL, NULL, level,
+                                              tx_secret, secretlen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+static int read_func(gnutls_session_t session,
+                     gnutls_record_encryption_level_t gtls_level,
+                     gnutls_handshake_description_t htype, const void *data,
+                     size_t datalen) {
+  ngtcp2_crypto_conn_ref *conn_ref = gnutls_session_get_ptr(session);
+  ngtcp2_conn *conn = conn_ref->get_conn(conn_ref);
+  ngtcp2_crypto_level level =
+      ngtcp2_crypto_gnutls_from_gnutls_record_encryption_level(gtls_level);
+  int rv;
+
+  if (htype == GNUTLS_HANDSHAKE_CHANGE_CIPHER_SPEC) {
+    return 0;
+  }
+
+  rv = ngtcp2_conn_submit_crypto_data(conn, level, data, datalen);
+  if (rv != 0) {
+    ngtcp2_conn_set_tls_error(conn, rv);
+    return -1;
+  }
+
+  return 0;
+}
+
+static int alert_read_func(gnutls_session_t session,
+                           gnutls_record_encryption_level_t gtls_level,
+                           gnutls_alert_level_t alert_level,
+                           gnutls_alert_description_t alert_desc) {
+  ngtcp2_crypto_conn_ref *conn_ref = gnutls_session_get_ptr(session);
+  ngtcp2_conn *conn = conn_ref->get_conn(conn_ref);
+  (void)gtls_level;
+  (void)alert_level;
+
+  ngtcp2_conn_set_tls_alert(conn, (uint8_t)alert_desc);
+
+  return 0;
+}
+
+static int tp_recv_func(gnutls_session_t session, const uint8_t *data,
+                        size_t datalen) {
+  ngtcp2_crypto_conn_ref *conn_ref = gnutls_session_get_ptr(session);
+  ngtcp2_conn *conn = conn_ref->get_conn(conn_ref);
+  int rv;
+
+  rv = ngtcp2_conn_decode_remote_transport_params(conn, data, datalen);
+  if (rv != 0) {
+    ngtcp2_conn_set_tls_error(conn, rv);
+    return -1;
+  }
+
+  return 0;
+}
+
+static int tp_send_func(gnutls_session_t session, gnutls_buffer_t extdata) {
+  ngtcp2_crypto_conn_ref *conn_ref = gnutls_session_get_ptr(session);
+  ngtcp2_conn *conn = conn_ref->get_conn(conn_ref);
+  uint8_t buf[256];
+  ngtcp2_ssize nwrite;
+  int rv;
+
+  nwrite = ngtcp2_conn_encode_local_transport_params(conn, buf, sizeof(buf));
+  if (nwrite < 0) {
+    return -1;
+  }
+
+  rv = gnutls_buffer_append_data(extdata, buf, (size_t)nwrite);
+  if (rv != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+static int crypto_gnutls_configure_session(gnutls_session_t session) {
+  int rv;
+
+  gnutls_handshake_set_secret_function(session, secret_func);
+  gnutls_handshake_set_read_function(session, read_func);
+  gnutls_alert_set_read_function(session, alert_read_func);
+
+  rv = gnutls_session_ext_register(
+      session, "QUIC Transport Parameters",
+      NGTCP2_TLSEXT_QUIC_TRANSPORT_PARAMETERS_V1, GNUTLS_EXT_TLS, tp_recv_func,
+      tp_send_func, NULL, NULL, NULL,
+      GNUTLS_EXT_FLAG_TLS | GNUTLS_EXT_FLAG_CLIENT_HELLO | GNUTLS_EXT_FLAG_EE);
+  if (rv != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_gnutls_configure_server_session(gnutls_session_t session) {
+  return crypto_gnutls_configure_session(session);
+}
+
+int ngtcp2_crypto_gnutls_configure_client_session(gnutls_session_t session) {
+  return crypto_gnutls_configure_session(session);
+}
diff --git a/src/contrib/libngtcp2/ngtcp2/crypto/shared.c b/src/contrib/libngtcp2/ngtcp2/crypto/shared.c
new file mode 100644
index 0000000..f38e0b1
--- /dev/null
+++ b/src/contrib/libngtcp2/ngtcp2/crypto/shared.c
@@ -0,0 +1,1418 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2019 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "shared.h"
+
+#ifdef WIN32
+#  include <winsock2.h>
+#  include <ws2tcpip.h>
+#else
+#  include <netinet/in.h>
+#endif
+
+#include <string.h>
+#include <assert.h>
+
+#include "ngtcp2_macro.h"
+#include "ngtcp2_net.h"
+
+ngtcp2_crypto_md *ngtcp2_crypto_md_init(ngtcp2_crypto_md *md,
+                                        void *md_native_handle) {
+  md->native_handle = md_native_handle;
+  return md;
+}
+
+int ngtcp2_crypto_hkdf_expand_label(uint8_t *dest, size_t destlen,
+                                    const ngtcp2_crypto_md *md,
+                                    const uint8_t *secret, size_t secretlen,
+                                    const uint8_t *label, size_t labellen) {
+  static const uint8_t LABEL[] = "tls13 ";
+  uint8_t info[256];
+  uint8_t *p = info;
+
+  *p++ = (uint8_t)(destlen / 256);
+  *p++ = (uint8_t)(destlen % 256);
+  *p++ = (uint8_t)(sizeof(LABEL) - 1 + labellen);
+  memcpy(p, LABEL, sizeof(LABEL) - 1);
+  p += sizeof(LABEL) - 1;
+  memcpy(p, label, labellen);
+  p += labellen;
+  *p++ = 0;
+
+  return ngtcp2_crypto_hkdf_expand(dest, destlen, md, secret, secretlen, info,
+                                   (size_t)(p - info));
+}
+
+#define NGTCP2_CRYPTO_INITIAL_SECRETLEN 32
+
+int ngtcp2_crypto_derive_initial_secrets(uint32_t version, uint8_t *rx_secret,
+                                         uint8_t *tx_secret,
+                                         uint8_t *initial_secret,
+                                         const ngtcp2_cid *client_dcid,
+                                         ngtcp2_crypto_side side) {
+  static const uint8_t CLABEL[] = "client in";
+  static const uint8_t SLABEL[] = "server in";
+  uint8_t initial_secret_buf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t *client_secret;
+  uint8_t *server_secret;
+  ngtcp2_crypto_ctx ctx;
+  const uint8_t *salt;
+  size_t saltlen;
+
+  if (!initial_secret) {
+    initial_secret = initial_secret_buf;
+  }
+
+  ngtcp2_crypto_ctx_initial(&ctx);
+
+  switch (version) {
+  case NGTCP2_PROTO_VER_V1:
+    salt = (const uint8_t *)NGTCP2_INITIAL_SALT_V1;
+    saltlen = sizeof(NGTCP2_INITIAL_SALT_V1) - 1;
+    break;
+  case NGTCP2_PROTO_VER_V2:
+    salt = (const uint8_t *)NGTCP2_INITIAL_SALT_V2;
+    saltlen = sizeof(NGTCP2_INITIAL_SALT_V2) - 1;
+    break;
+  default:
+    salt = (const uint8_t *)NGTCP2_INITIAL_SALT_DRAFT;
+    saltlen = sizeof(NGTCP2_INITIAL_SALT_DRAFT) - 1;
+  }
+
+  if (ngtcp2_crypto_hkdf_extract(initial_secret, &ctx.md, client_dcid->data,
+                                 client_dcid->datalen, salt, saltlen) != 0) {
+    return -1;
+  }
+
+  if (side == NGTCP2_CRYPTO_SIDE_SERVER) {
+    client_secret = rx_secret;
+    server_secret = tx_secret;
+  } else {
+    client_secret = tx_secret;
+    server_secret = rx_secret;
+  }
+
+  if (ngtcp2_crypto_hkdf_expand_label(
+          client_secret, NGTCP2_CRYPTO_INITIAL_SECRETLEN, &ctx.md,
+          initial_secret, NGTCP2_CRYPTO_INITIAL_SECRETLEN, CLABEL,
+          sizeof(CLABEL) - 1) != 0 ||
+      ngtcp2_crypto_hkdf_expand_label(
+          server_secret, NGTCP2_CRYPTO_INITIAL_SECRETLEN, &ctx.md,
+          initial_secret, NGTCP2_CRYPTO_INITIAL_SECRETLEN, SLABEL,
+          sizeof(SLABEL) - 1) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+size_t ngtcp2_crypto_packet_protection_ivlen(const ngtcp2_crypto_aead *aead) {
+  size_t noncelen = ngtcp2_crypto_aead_noncelen(aead);
+  return ngtcp2_max(8, noncelen);
+}
+
+int ngtcp2_crypto_derive_packet_protection_key(
+    uint8_t *key, uint8_t *iv, uint8_t *hp_key, uint32_t version,
+    const ngtcp2_crypto_aead *aead, const ngtcp2_crypto_md *md,
+    const uint8_t *secret, size_t secretlen) {
+  static const uint8_t KEY_LABEL_V1[] = "quic key";
+  static const uint8_t IV_LABEL_V1[] = "quic iv";
+  static const uint8_t HP_KEY_LABEL_V1[] = "quic hp";
+  static const uint8_t KEY_LABEL_V2[] = "quicv2 key";
+  static const uint8_t IV_LABEL_V2[] = "quicv2 iv";
+  static const uint8_t HP_KEY_LABEL_V2[] = "quicv2 hp";
+  size_t keylen = ngtcp2_crypto_aead_keylen(aead);
+  size_t ivlen = ngtcp2_crypto_packet_protection_ivlen(aead);
+  const uint8_t *key_label;
+  size_t key_labellen;
+  const uint8_t *iv_label;
+  size_t iv_labellen;
+  const uint8_t *hp_key_label;
+  size_t hp_key_labellen;
+
+  switch (version) {
+  case NGTCP2_PROTO_VER_V2:
+    key_label = KEY_LABEL_V2;
+    key_labellen = sizeof(KEY_LABEL_V2) - 1;
+    iv_label = IV_LABEL_V2;
+    iv_labellen = sizeof(IV_LABEL_V2) - 1;
+    hp_key_label = HP_KEY_LABEL_V2;
+    hp_key_labellen = sizeof(HP_KEY_LABEL_V2) - 1;
+    break;
+  default:
+    key_label = KEY_LABEL_V1;
+    key_labellen = sizeof(KEY_LABEL_V1) - 1;
+    iv_label = IV_LABEL_V1;
+    iv_labellen = sizeof(IV_LABEL_V1) - 1;
+    hp_key_label = HP_KEY_LABEL_V1;
+    hp_key_labellen = sizeof(HP_KEY_LABEL_V1) - 1;
+  }
+
+  if (ngtcp2_crypto_hkdf_expand_label(key, keylen, md, secret, secretlen,
+                                      key_label, key_labellen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_hkdf_expand_label(iv, ivlen, md, secret, secretlen,
+                                      iv_label, iv_labellen) != 0) {
+    return -1;
+  }
+
+  if (hp_key != NULL &&
+      ngtcp2_crypto_hkdf_expand_label(hp_key, keylen, md, secret, secretlen,
+                                      hp_key_label, hp_key_labellen) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_update_traffic_secret(uint8_t *dest,
+                                        const ngtcp2_crypto_md *md,
+                                        const uint8_t *secret,
+                                        size_t secretlen) {
+  static const uint8_t LABEL[] = "quic ku";
+
+  if (ngtcp2_crypto_hkdf_expand_label(dest, secretlen, md, secret, secretlen,
+                                      LABEL, sizeof(LABEL) - 1) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_derive_and_install_rx_key(ngtcp2_conn *conn, uint8_t *key,
+                                            uint8_t *iv, uint8_t *hp_key,
+                                            ngtcp2_crypto_level level,
+                                            const uint8_t *secret,
+                                            size_t secretlen) {
+  const ngtcp2_crypto_ctx *ctx;
+  const ngtcp2_crypto_aead *aead;
+  const ngtcp2_crypto_md *md;
+  const ngtcp2_crypto_cipher *hp;
+  ngtcp2_crypto_aead_ctx aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx hp_ctx = {0};
+  void *tls = ngtcp2_conn_get_tls_native_handle(conn);
+  uint8_t keybuf[64], ivbuf[64], hp_keybuf[64];
+  size_t ivlen;
+  int rv;
+  ngtcp2_crypto_ctx cctx;
+  uint32_t version;
+
+  if (level == NGTCP2_CRYPTO_LEVEL_EARLY && !ngtcp2_conn_is_server(conn)) {
+    return 0;
+  }
+
+  if (!key) {
+    key = keybuf;
+  }
+  if (!iv) {
+    iv = ivbuf;
+  }
+  if (!hp_key) {
+    hp_key = hp_keybuf;
+  }
+
+  switch (level) {
+  case NGTCP2_CRYPTO_LEVEL_EARLY:
+    ngtcp2_crypto_ctx_tls_early(&cctx, tls);
+    ngtcp2_conn_set_early_crypto_ctx(conn, &cctx);
+    ctx = ngtcp2_conn_get_early_crypto_ctx(conn);
+    version = ngtcp2_conn_get_client_chosen_version(conn);
+    break;
+  case NGTCP2_CRYPTO_LEVEL_HANDSHAKE:
+    if (ngtcp2_conn_is_server(conn) &&
+        !ngtcp2_conn_get_negotiated_version(conn)) {
+      rv = ngtcp2_crypto_set_remote_transport_params(conn, tls);
+      if (rv != 0) {
+        return -1;
+      }
+    }
+    /* fall through */
+  default:
+    ctx = ngtcp2_conn_get_crypto_ctx(conn);
+    version = ngtcp2_conn_get_negotiated_version(conn);
+
+    if (!ctx->aead.native_handle) {
+      ngtcp2_crypto_ctx_tls(&cctx, tls);
+      ngtcp2_conn_set_crypto_ctx(conn, &cctx);
+      ctx = ngtcp2_conn_get_crypto_ctx(conn);
+    }
+  }
+
+  aead = &ctx->aead;
+  md = &ctx->md;
+  hp = &ctx->hp;
+  ivlen = ngtcp2_crypto_packet_protection_ivlen(aead);
+
+  if (ngtcp2_crypto_derive_packet_protection_key(key, iv, hp_key, version, aead,
+                                                 md, secret, secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(&aead_ctx, aead, key, ivlen) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&hp_ctx, hp, hp_key) != 0) {
+    goto fail;
+  }
+
+  switch (level) {
+  case NGTCP2_CRYPTO_LEVEL_EARLY:
+    rv = ngtcp2_conn_install_early_key(conn, &aead_ctx, iv, ivlen, &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+    break;
+  case NGTCP2_CRYPTO_LEVEL_HANDSHAKE:
+    rv = ngtcp2_conn_install_rx_handshake_key(conn, &aead_ctx, iv, ivlen,
+                                              &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+    break;
+  case NGTCP2_CRYPTO_LEVEL_APPLICATION:
+    if (!ngtcp2_conn_is_server(conn)) {
+      rv = ngtcp2_crypto_set_remote_transport_params(conn, tls);
+      if (rv != 0) {
+        goto fail;
+      }
+    }
+
+    rv = ngtcp2_conn_install_rx_key(conn, secret, secretlen, &aead_ctx, iv,
+                                    ivlen, &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+
+    break;
+  default:
+    goto fail;
+  }
+
+  return 0;
+
+fail:
+  ngtcp2_crypto_cipher_ctx_free(&hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  return -1;
+}
+
+/*
+ * crypto_set_local_transport_params gets local QUIC transport
+ * parameters from |conn| and sets it to |tls|.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+static int crypto_set_local_transport_params(ngtcp2_conn *conn, void *tls) {
+  ngtcp2_ssize nwrite;
+  uint8_t buf[256];
+
+  nwrite = ngtcp2_conn_encode_local_transport_params(conn, buf, sizeof(buf));
+  if (nwrite < 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_set_local_transport_params(tls, buf, (size_t)nwrite) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_derive_and_install_tx_key(ngtcp2_conn *conn, uint8_t *key,
+                                            uint8_t *iv, uint8_t *hp_key,
+                                            ngtcp2_crypto_level level,
+                                            const uint8_t *secret,
+                                            size_t secretlen) {
+  const ngtcp2_crypto_ctx *ctx;
+  const ngtcp2_crypto_aead *aead;
+  const ngtcp2_crypto_md *md;
+  const ngtcp2_crypto_cipher *hp;
+  ngtcp2_crypto_aead_ctx aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx hp_ctx = {0};
+  void *tls = ngtcp2_conn_get_tls_native_handle(conn);
+  uint8_t keybuf[64], ivbuf[64], hp_keybuf[64];
+  size_t ivlen;
+  int rv;
+  ngtcp2_crypto_ctx cctx;
+  uint32_t version;
+
+  if (level == NGTCP2_CRYPTO_LEVEL_EARLY && ngtcp2_conn_is_server(conn)) {
+    return 0;
+  }
+
+  if (!key) {
+    key = keybuf;
+  }
+  if (!iv) {
+    iv = ivbuf;
+  }
+  if (!hp_key) {
+    hp_key = hp_keybuf;
+  }
+
+  switch (level) {
+  case NGTCP2_CRYPTO_LEVEL_EARLY:
+    ngtcp2_crypto_ctx_tls_early(&cctx, tls);
+    ngtcp2_conn_set_early_crypto_ctx(conn, &cctx);
+    ctx = ngtcp2_conn_get_early_crypto_ctx(conn);
+    version = ngtcp2_conn_get_client_chosen_version(conn);
+    break;
+  case NGTCP2_CRYPTO_LEVEL_HANDSHAKE:
+    if (ngtcp2_conn_is_server(conn) &&
+        !ngtcp2_conn_get_negotiated_version(conn)) {
+      rv = ngtcp2_crypto_set_remote_transport_params(conn, tls);
+      if (rv != 0) {
+        return -1;
+      }
+    }
+    /* fall through */
+  default:
+    ctx = ngtcp2_conn_get_crypto_ctx(conn);
+    version = ngtcp2_conn_get_negotiated_version(conn);
+
+    if (!ctx->aead.native_handle) {
+      ngtcp2_crypto_ctx_tls(&cctx, tls);
+      ngtcp2_conn_set_crypto_ctx(conn, &cctx);
+      ctx = ngtcp2_conn_get_crypto_ctx(conn);
+    }
+  }
+
+  aead = &ctx->aead;
+  md = &ctx->md;
+  hp = &ctx->hp;
+  ivlen = ngtcp2_crypto_packet_protection_ivlen(aead);
+
+  if (ngtcp2_crypto_derive_packet_protection_key(key, iv, hp_key, version, aead,
+                                                 md, secret, secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&aead_ctx, aead, key, ivlen) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&hp_ctx, hp, hp_key) != 0) {
+    goto fail;
+  }
+
+  switch (level) {
+  case NGTCP2_CRYPTO_LEVEL_EARLY:
+    rv = ngtcp2_conn_install_early_key(conn, &aead_ctx, iv, ivlen, &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+    break;
+  case NGTCP2_CRYPTO_LEVEL_HANDSHAKE:
+    rv = ngtcp2_conn_install_tx_handshake_key(conn, &aead_ctx, iv, ivlen,
+                                              &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+
+    if (ngtcp2_conn_is_server(conn) &&
+        crypto_set_local_transport_params(conn, tls) != 0) {
+      goto fail;
+    }
+
+    break;
+  case NGTCP2_CRYPTO_LEVEL_APPLICATION:
+    rv = ngtcp2_conn_install_tx_key(conn, secret, secretlen, &aead_ctx, iv,
+                                    ivlen, &hp_ctx);
+    if (rv != 0) {
+      goto fail;
+    }
+
+    break;
+  default:
+    goto fail;
+  }
+
+  return 0;
+
+fail:
+  ngtcp2_crypto_cipher_ctx_free(&hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  return -1;
+}
+
+int ngtcp2_crypto_derive_and_install_initial_key(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    uint8_t *initial_secret, uint8_t *rx_key, uint8_t *rx_iv,
+    uint8_t *rx_hp_key, uint8_t *tx_key, uint8_t *tx_iv, uint8_t *tx_hp_key,
+    uint32_t version, const ngtcp2_cid *client_dcid) {
+  uint8_t rx_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t tx_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t initial_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t rx_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t rx_ivbuf[NGTCP2_CRYPTO_INITIAL_IVLEN];
+  uint8_t rx_hp_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t tx_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t tx_ivbuf[NGTCP2_CRYPTO_INITIAL_IVLEN];
+  uint8_t tx_hp_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  ngtcp2_crypto_ctx ctx;
+  ngtcp2_crypto_aead retry_aead;
+  ngtcp2_crypto_aead_ctx rx_aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx rx_hp_ctx = {0};
+  ngtcp2_crypto_aead_ctx tx_aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx tx_hp_ctx = {0};
+  ngtcp2_crypto_aead_ctx retry_aead_ctx = {0};
+  int rv;
+  int server = ngtcp2_conn_is_server(conn);
+  const uint8_t *retry_key;
+  size_t retry_noncelen;
+
+  ngtcp2_crypto_ctx_initial(&ctx);
+
+  if (!rx_secret) {
+    rx_secret = rx_secretbuf;
+  }
+  if (!tx_secret) {
+    tx_secret = tx_secretbuf;
+  }
+  if (!initial_secret) {
+    initial_secret = initial_secretbuf;
+  }
+
+  if (!rx_key) {
+    rx_key = rx_keybuf;
+  }
+  if (!rx_iv) {
+    rx_iv = rx_ivbuf;
+  }
+  if (!rx_hp_key) {
+    rx_hp_key = rx_hp_keybuf;
+  }
+  if (!tx_key) {
+    tx_key = tx_keybuf;
+  }
+  if (!tx_iv) {
+    tx_iv = tx_ivbuf;
+  }
+  if (!tx_hp_key) {
+    tx_hp_key = tx_hp_keybuf;
+  }
+
+  ngtcp2_conn_set_initial_crypto_ctx(conn, &ctx);
+
+  if (ngtcp2_crypto_derive_initial_secrets(
+          version, rx_secret, tx_secret, initial_secret, client_dcid,
+          server ? NGTCP2_CRYPTO_SIDE_SERVER : NGTCP2_CRYPTO_SIDE_CLIENT) !=
+      0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          rx_key, rx_iv, rx_hp_key, version, &ctx.aead, &ctx.md, rx_secret,
+          NGTCP2_CRYPTO_INITIAL_SECRETLEN) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          tx_key, tx_iv, tx_hp_key, version, &ctx.aead, &ctx.md, tx_secret,
+          NGTCP2_CRYPTO_INITIAL_SECRETLEN) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(&rx_aead_ctx, &ctx.aead, rx_key,
+                                          NGTCP2_CRYPTO_INITIAL_IVLEN) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&rx_hp_ctx, &ctx.hp, rx_hp_key) !=
+      0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&tx_aead_ctx, &ctx.aead, tx_key,
+                                          NGTCP2_CRYPTO_INITIAL_IVLEN) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&tx_hp_ctx, &ctx.hp, tx_hp_key) !=
+      0) {
+    goto fail;
+  }
+
+  if (!server && !ngtcp2_conn_after_retry(conn)) {
+    ngtcp2_crypto_aead_retry(&retry_aead);
+
+    switch (version) {
+    case NGTCP2_PROTO_VER_V1:
+      retry_key = (const uint8_t *)NGTCP2_RETRY_KEY_V1;
+      retry_noncelen = sizeof(NGTCP2_RETRY_NONCE_V1) - 1;
+      break;
+    case NGTCP2_PROTO_VER_V2:
+      retry_key = (const uint8_t *)NGTCP2_RETRY_KEY_V2;
+      retry_noncelen = sizeof(NGTCP2_RETRY_NONCE_V2) - 1;
+      break;
+    default:
+      retry_key = (const uint8_t *)NGTCP2_RETRY_KEY_DRAFT;
+      retry_noncelen = sizeof(NGTCP2_RETRY_NONCE_DRAFT) - 1;
+    }
+
+    if (ngtcp2_crypto_aead_ctx_encrypt_init(&retry_aead_ctx, &retry_aead,
+                                            retry_key, retry_noncelen) != 0) {
+      goto fail;
+    }
+  }
+
+  rv = ngtcp2_conn_install_initial_key(conn, &rx_aead_ctx, rx_iv, &rx_hp_ctx,
+                                       &tx_aead_ctx, tx_iv, &tx_hp_ctx,
+                                       NGTCP2_CRYPTO_INITIAL_IVLEN);
+  if (rv != 0) {
+    goto fail;
+  }
+
+  if (retry_aead_ctx.native_handle) {
+    ngtcp2_conn_set_retry_aead(conn, &retry_aead, &retry_aead_ctx);
+  }
+
+  return 0;
+
+fail:
+  ngtcp2_crypto_aead_ctx_free(&retry_aead_ctx);
+  ngtcp2_crypto_cipher_ctx_free(&tx_hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&tx_aead_ctx);
+  ngtcp2_crypto_cipher_ctx_free(&rx_hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&rx_aead_ctx);
+
+  return -1;
+}
+
+int ngtcp2_crypto_derive_and_install_vneg_initial_key(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    uint8_t *initial_secret, uint8_t *rx_key, uint8_t *rx_iv,
+    uint8_t *rx_hp_key, uint8_t *tx_key, uint8_t *tx_iv, uint8_t *tx_hp_key,
+    uint32_t version, const ngtcp2_cid *client_dcid) {
+  uint8_t rx_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t tx_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t initial_secretbuf[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t rx_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t rx_ivbuf[NGTCP2_CRYPTO_INITIAL_IVLEN];
+  uint8_t rx_hp_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t tx_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t tx_ivbuf[NGTCP2_CRYPTO_INITIAL_IVLEN];
+  uint8_t tx_hp_keybuf[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  const ngtcp2_crypto_ctx *ctx = ngtcp2_conn_get_initial_crypto_ctx(conn);
+  ngtcp2_crypto_aead_ctx rx_aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx rx_hp_ctx = {0};
+  ngtcp2_crypto_aead_ctx tx_aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx tx_hp_ctx = {0};
+  int rv;
+  int server = ngtcp2_conn_is_server(conn);
+
+  if (!rx_secret) {
+    rx_secret = rx_secretbuf;
+  }
+  if (!tx_secret) {
+    tx_secret = tx_secretbuf;
+  }
+  if (!initial_secret) {
+    initial_secret = initial_secretbuf;
+  }
+
+  if (!rx_key) {
+    rx_key = rx_keybuf;
+  }
+  if (!rx_iv) {
+    rx_iv = rx_ivbuf;
+  }
+  if (!rx_hp_key) {
+    rx_hp_key = rx_hp_keybuf;
+  }
+  if (!tx_key) {
+    tx_key = tx_keybuf;
+  }
+  if (!tx_iv) {
+    tx_iv = tx_ivbuf;
+  }
+  if (!tx_hp_key) {
+    tx_hp_key = tx_hp_keybuf;
+  }
+
+  if (ngtcp2_crypto_derive_initial_secrets(
+          version, rx_secret, tx_secret, initial_secret, client_dcid,
+          server ? NGTCP2_CRYPTO_SIDE_SERVER : NGTCP2_CRYPTO_SIDE_CLIENT) !=
+      0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          rx_key, rx_iv, rx_hp_key, version, &ctx->aead, &ctx->md, rx_secret,
+          NGTCP2_CRYPTO_INITIAL_SECRETLEN) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          tx_key, tx_iv, tx_hp_key, version, &ctx->aead, &ctx->md, tx_secret,
+          NGTCP2_CRYPTO_INITIAL_SECRETLEN) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(&rx_aead_ctx, &ctx->aead, rx_key,
+                                          NGTCP2_CRYPTO_INITIAL_IVLEN) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&rx_hp_ctx, &ctx->hp, rx_hp_key) !=
+      0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&tx_aead_ctx, &ctx->aead, tx_key,
+                                          NGTCP2_CRYPTO_INITIAL_IVLEN) != 0) {
+    goto fail;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&tx_hp_ctx, &ctx->hp, tx_hp_key) !=
+      0) {
+    goto fail;
+  }
+
+  rv = ngtcp2_conn_install_vneg_initial_key(
+      conn, version, &rx_aead_ctx, rx_iv, &rx_hp_ctx, &tx_aead_ctx, tx_iv,
+      &tx_hp_ctx, NGTCP2_CRYPTO_INITIAL_IVLEN);
+  if (rv != 0) {
+    goto fail;
+  }
+
+  return 0;
+
+fail:
+  ngtcp2_crypto_cipher_ctx_free(&tx_hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&tx_aead_ctx);
+  ngtcp2_crypto_cipher_ctx_free(&rx_hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&rx_aead_ctx);
+
+  return -1;
+}
+
+int ngtcp2_crypto_update_key(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    ngtcp2_crypto_aead_ctx *rx_aead_ctx, uint8_t *rx_key, uint8_t *rx_iv,
+    ngtcp2_crypto_aead_ctx *tx_aead_ctx, uint8_t *tx_key, uint8_t *tx_iv,
+    const uint8_t *current_rx_secret, const uint8_t *current_tx_secret,
+    size_t secretlen) {
+  const ngtcp2_crypto_ctx *ctx = ngtcp2_conn_get_crypto_ctx(conn);
+  const ngtcp2_crypto_aead *aead = &ctx->aead;
+  const ngtcp2_crypto_md *md = &ctx->md;
+  size_t ivlen = ngtcp2_crypto_packet_protection_ivlen(aead);
+  uint32_t version = ngtcp2_conn_get_negotiated_version(conn);
+
+  if (ngtcp2_crypto_update_traffic_secret(rx_secret, md, current_rx_secret,
+                                          secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          rx_key, rx_iv, NULL, version, aead, md, rx_secret, secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_update_traffic_secret(tx_secret, md, current_tx_secret,
+                                          secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          tx_key, tx_iv, NULL, version, aead, md, tx_secret, secretlen) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(rx_aead_ctx, aead, rx_key, ivlen) !=
+      0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(tx_aead_ctx, aead, tx_key, ivlen) !=
+      0) {
+    ngtcp2_crypto_aead_ctx_free(rx_aead_ctx);
+    rx_aead_ctx->native_handle = NULL;
+    return -1;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_encrypt_cb(uint8_t *dest, const ngtcp2_crypto_aead *aead,
+                             const ngtcp2_crypto_aead_ctx *aead_ctx,
+                             const uint8_t *plaintext, size_t plaintextlen,
+                             const uint8_t *nonce, size_t noncelen,
+                             const uint8_t *aad, size_t aadlen) {
+  if (ngtcp2_crypto_encrypt(dest, aead, aead_ctx, plaintext, plaintextlen,
+                            nonce, noncelen, aad, aadlen) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+  return 0;
+}
+
+int ngtcp2_crypto_decrypt_cb(uint8_t *dest, const ngtcp2_crypto_aead *aead,
+                             const ngtcp2_crypto_aead_ctx *aead_ctx,
+                             const uint8_t *ciphertext, size_t ciphertextlen,
+                             const uint8_t *nonce, size_t noncelen,
+                             const uint8_t *aad, size_t aadlen) {
+  if (ngtcp2_crypto_decrypt(dest, aead, aead_ctx, ciphertext, ciphertextlen,
+                            nonce, noncelen, aad, aadlen) != 0) {
+    return NGTCP2_ERR_DECRYPT;
+  }
+  return 0;
+}
+
+int ngtcp2_crypto_hp_mask_cb(uint8_t *dest, const ngtcp2_crypto_cipher *hp,
+                             const ngtcp2_crypto_cipher_ctx *hp_ctx,
+                             const uint8_t *sample) {
+  if (ngtcp2_crypto_hp_mask(dest, hp, hp_ctx, sample) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+  return 0;
+}
+
+int ngtcp2_crypto_update_key_cb(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    ngtcp2_crypto_aead_ctx *rx_aead_ctx, uint8_t *rx_iv,
+    ngtcp2_crypto_aead_ctx *tx_aead_ctx, uint8_t *tx_iv,
+    const uint8_t *current_rx_secret, const uint8_t *current_tx_secret,
+    size_t secretlen, void *user_data) {
+  uint8_t rx_key[64];
+  uint8_t tx_key[64];
+  (void)conn;
+  (void)user_data;
+
+  if (ngtcp2_crypto_update_key(conn, rx_secret, tx_secret, rx_aead_ctx, rx_key,
+                               rx_iv, tx_aead_ctx, tx_key, tx_iv,
+                               current_rx_secret, current_tx_secret,
+                               secretlen) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+  return 0;
+}
+
+int ngtcp2_crypto_generate_stateless_reset_token(uint8_t *token,
+                                                 const uint8_t *secret,
+                                                 size_t secretlen,
+                                                 const ngtcp2_cid *cid) {
+  static const uint8_t info[] = "stateless_reset";
+  ngtcp2_crypto_md md;
+
+  if (ngtcp2_crypto_hkdf(token, NGTCP2_STATELESS_RESET_TOKENLEN,
+                         ngtcp2_crypto_md_sha256(&md), secret, secretlen,
+                         cid->data, cid->datalen, info,
+                         sizeof(info) - 1) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+static int crypto_derive_token_key(uint8_t *key, size_t keylen, uint8_t *iv,
+                                   size_t ivlen, const ngtcp2_crypto_md *md,
+                                   const uint8_t *secret, size_t secretlen,
+                                   const uint8_t *salt, size_t saltlen,
+                                   const uint8_t *info_prefix,
+                                   size_t info_prefixlen) {
+  static const uint8_t key_info_suffix[] = " key";
+  static const uint8_t iv_info_suffix[] = " iv";
+  uint8_t intsecret[32];
+  uint8_t info[32];
+  uint8_t *p;
+
+  assert(ngtcp2_crypto_md_hashlen(md) == sizeof(intsecret));
+  assert(info_prefixlen + sizeof(key_info_suffix) - 1 <= sizeof(info));
+  assert(info_prefixlen + sizeof(iv_info_suffix) - 1 <= sizeof(info));
+
+  if (ngtcp2_crypto_hkdf_extract(intsecret, md, secret, secretlen, salt,
+                                 saltlen) != 0) {
+    return -1;
+  }
+
+  memcpy(info, info_prefix, info_prefixlen);
+  p = info + info_prefixlen;
+
+  memcpy(p, key_info_suffix, sizeof(key_info_suffix) - 1);
+  p += sizeof(key_info_suffix) - 1;
+
+  if (ngtcp2_crypto_hkdf_expand(key, keylen, md, intsecret, sizeof(intsecret),
+                                info, (size_t)(p - info)) != 0) {
+    return -1;
+  }
+
+  p = info + info_prefixlen;
+
+  memcpy(p, iv_info_suffix, sizeof(iv_info_suffix) - 1);
+  p += sizeof(iv_info_suffix) - 1;
+
+  if (ngtcp2_crypto_hkdf_expand(iv, ivlen, md, intsecret, sizeof(intsecret),
+                                info, (size_t)(p - info)) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+static size_t crypto_generate_retry_token_aad(uint8_t *dest, uint32_t version,
+                                              const ngtcp2_sockaddr *sa,
+                                              ngtcp2_socklen salen,
+                                              const ngtcp2_cid *retry_scid) {
+  uint8_t *p = dest;
+
+  version = ngtcp2_htonl(version);
+  memcpy(p, &version, sizeof(version));
+  memcpy(p, sa, (size_t)salen);
+  p += salen;
+  memcpy(p, retry_scid->data, retry_scid->datalen);
+  p += retry_scid->datalen;
+
+  return (size_t)(p - dest);
+}
+
+static const uint8_t retry_token_info_prefix[] = "retry_token";
+
+ngtcp2_ssize ngtcp2_crypto_generate_retry_token(
+    uint8_t *token, const uint8_t *secret, size_t secretlen, uint32_t version,
+    const ngtcp2_sockaddr *remote_addr, ngtcp2_socklen remote_addrlen,
+    const ngtcp2_cid *retry_scid, const ngtcp2_cid *odcid, ngtcp2_tstamp ts) {
+  uint8_t plaintext[NGTCP2_CRYPTO_MAX_RETRY_TOKENLEN];
+  uint8_t rand_data[NGTCP2_CRYPTO_TOKEN_RAND_DATALEN];
+  uint8_t key[32];
+  uint8_t iv[32];
+  size_t keylen;
+  size_t ivlen;
+  ngtcp2_crypto_aead aead;
+  ngtcp2_crypto_md md;
+  ngtcp2_crypto_aead_ctx aead_ctx;
+  size_t plaintextlen;
+  uint8_t aad[sizeof(version) + sizeof(ngtcp2_sockaddr_storage) +
+              NGTCP2_MAX_CIDLEN];
+  size_t aadlen;
+  uint8_t *p = plaintext;
+  ngtcp2_tstamp ts_be = ngtcp2_htonl64(ts);
+  int rv;
+
+  memset(plaintext, 0, sizeof(plaintext));
+
+  *p++ = (uint8_t)odcid->datalen;
+  memcpy(p, odcid->data, odcid->datalen);
+  p += NGTCP2_MAX_CIDLEN;
+  memcpy(p, &ts_be, sizeof(ts_be));
+  p += sizeof(ts_be);
+
+  plaintextlen = (size_t)(p - plaintext);
+
+  if (ngtcp2_crypto_random(rand_data, sizeof(rand_data)) != 0) {
+    return -1;
+  }
+
+  ngtcp2_crypto_aead_aes_128_gcm(&aead);
+  ngtcp2_crypto_md_sha256(&md);
+
+  keylen = ngtcp2_crypto_aead_keylen(&aead);
+  ivlen = ngtcp2_crypto_aead_noncelen(&aead);
+
+  assert(sizeof(key) >= keylen);
+  assert(sizeof(iv) >= ivlen);
+
+  if (crypto_derive_token_key(key, keylen, iv, ivlen, &md, secret, secretlen,
+                              rand_data, sizeof(rand_data),
+                              retry_token_info_prefix,
+                              sizeof(retry_token_info_prefix) - 1) != 0) {
+    return -1;
+  }
+
+  aadlen = crypto_generate_retry_token_aad(aad, version, remote_addr,
+                                           remote_addrlen, retry_scid);
+
+  p = token;
+  *p++ = NGTCP2_CRYPTO_TOKEN_MAGIC_RETRY;
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&aead_ctx, &aead, key, ivlen) != 0) {
+    return -1;
+  }
+
+  rv = ngtcp2_crypto_encrypt(p, &aead, &aead_ctx, plaintext, plaintextlen, iv,
+                             ivlen, aad, aadlen);
+
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  if (rv != 0) {
+    return -1;
+  }
+
+  p += plaintextlen + aead.max_overhead;
+  memcpy(p, rand_data, sizeof(rand_data));
+  p += sizeof(rand_data);
+
+  return p - token;
+}
+
+int ngtcp2_crypto_verify_retry_token(
+    ngtcp2_cid *odcid, const uint8_t *token, size_t tokenlen,
+    const uint8_t *secret, size_t secretlen, uint32_t version,
+    const ngtcp2_sockaddr *remote_addr, ngtcp2_socklen remote_addrlen,
+    const ngtcp2_cid *dcid, ngtcp2_duration timeout, ngtcp2_tstamp ts) {
+  uint8_t
+      plaintext[/* cid len = */ 1 + NGTCP2_MAX_CIDLEN + sizeof(ngtcp2_tstamp)];
+  uint8_t key[32];
+  uint8_t iv[32];
+  size_t keylen;
+  size_t ivlen;
+  ngtcp2_crypto_aead_ctx aead_ctx;
+  ngtcp2_crypto_aead aead;
+  ngtcp2_crypto_md md;
+  uint8_t aad[sizeof(version) + sizeof(ngtcp2_sockaddr_storage) +
+              NGTCP2_MAX_CIDLEN];
+  size_t aadlen;
+  const uint8_t *rand_data;
+  const uint8_t *ciphertext;
+  size_t ciphertextlen;
+  size_t cil;
+  int rv;
+  ngtcp2_tstamp gen_ts;
+
+  if (tokenlen != NGTCP2_CRYPTO_MAX_RETRY_TOKENLEN ||
+      token[0] != NGTCP2_CRYPTO_TOKEN_MAGIC_RETRY) {
+    return -1;
+  }
+
+  rand_data = token + tokenlen - NGTCP2_CRYPTO_TOKEN_RAND_DATALEN;
+  ciphertext = token + 1;
+  ciphertextlen = tokenlen - 1 - NGTCP2_CRYPTO_TOKEN_RAND_DATALEN;
+
+  ngtcp2_crypto_aead_aes_128_gcm(&aead);
+  ngtcp2_crypto_md_sha256(&md);
+
+  keylen = ngtcp2_crypto_aead_keylen(&aead);
+  ivlen = ngtcp2_crypto_aead_noncelen(&aead);
+
+  if (crypto_derive_token_key(key, keylen, iv, ivlen, &md, secret, secretlen,
+                              rand_data, NGTCP2_CRYPTO_TOKEN_RAND_DATALEN,
+                              retry_token_info_prefix,
+                              sizeof(retry_token_info_prefix) - 1) != 0) {
+    return -1;
+  }
+
+  aadlen = crypto_generate_retry_token_aad(aad, version, remote_addr,
+                                           remote_addrlen, dcid);
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(&aead_ctx, &aead, key, ivlen) != 0) {
+    return -1;
+  }
+
+  rv = ngtcp2_crypto_decrypt(plaintext, &aead, &aead_ctx, ciphertext,
+                             ciphertextlen, iv, ivlen, aad, aadlen);
+
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  if (rv != 0) {
+    return -1;
+  }
+
+  cil = plaintext[0];
+
+  assert(cil == 0 || (cil >= NGTCP2_MIN_CIDLEN && cil <= NGTCP2_MAX_CIDLEN));
+
+  memcpy(&gen_ts, plaintext + /* cid len = */ 1 + NGTCP2_MAX_CIDLEN,
+         sizeof(gen_ts));
+
+  gen_ts = ngtcp2_ntohl64(gen_ts);
+  if (gen_ts + timeout <= ts) {
+    return -1;
+  }
+
+  ngtcp2_cid_init(odcid, plaintext + /* cid len = */ 1, cil);
+
+  return 0;
+}
+
+static size_t crypto_generate_regular_token_aad(uint8_t *dest,
+                                                const ngtcp2_sockaddr *sa) {
+  const uint8_t *addr;
+  size_t addrlen;
+
+  switch (sa->sa_family) {
+  case AF_INET:
+    addr = (const uint8_t *)&((const ngtcp2_sockaddr_in *)(void *)sa)->sin_addr;
+    addrlen = sizeof(((const ngtcp2_sockaddr_in *)(void *)sa)->sin_addr);
+    break;
+  case AF_INET6:
+    addr =
+        (const uint8_t *)&((const ngtcp2_sockaddr_in6 *)(void *)sa)->sin6_addr;
+    addrlen = sizeof(((const ngtcp2_sockaddr_in6 *)(void *)sa)->sin6_addr);
+    break;
+  default:
+    assert(0);
+    abort();
+  }
+
+  memcpy(dest, addr, addrlen);
+
+  return addrlen;
+}
+
+static const uint8_t regular_token_info_prefix[] = "regular_token";
+
+ngtcp2_ssize ngtcp2_crypto_generate_regular_token(
+    uint8_t *token, const uint8_t *secret, size_t secretlen,
+    const ngtcp2_sockaddr *remote_addr, ngtcp2_socklen remote_addrlen,
+    ngtcp2_tstamp ts) {
+  uint8_t plaintext[sizeof(ngtcp2_tstamp)];
+  uint8_t rand_data[NGTCP2_CRYPTO_TOKEN_RAND_DATALEN];
+  uint8_t key[32];
+  uint8_t iv[32];
+  size_t keylen;
+  size_t ivlen;
+  ngtcp2_crypto_aead aead;
+  ngtcp2_crypto_md md;
+  ngtcp2_crypto_aead_ctx aead_ctx;
+  size_t plaintextlen;
+  uint8_t aad[sizeof(ngtcp2_sockaddr_in6)];
+  size_t aadlen;
+  uint8_t *p = plaintext;
+  ngtcp2_tstamp ts_be = ngtcp2_htonl64(ts);
+  int rv;
+  (void)remote_addrlen;
+
+  memcpy(p, &ts_be, sizeof(ts_be));
+  p += sizeof(ts_be);
+
+  plaintextlen = (size_t)(p - plaintext);
+
+  if (ngtcp2_crypto_random(rand_data, sizeof(rand_data)) != 0) {
+    return -1;
+  }
+
+  ngtcp2_crypto_aead_aes_128_gcm(&aead);
+  ngtcp2_crypto_md_sha256(&md);
+
+  keylen = ngtcp2_crypto_aead_keylen(&aead);
+  ivlen = ngtcp2_crypto_aead_noncelen(&aead);
+
+  assert(sizeof(key) >= keylen);
+  assert(sizeof(iv) >= ivlen);
+
+  if (crypto_derive_token_key(key, keylen, iv, ivlen, &md, secret, secretlen,
+                              rand_data, sizeof(rand_data),
+                              regular_token_info_prefix,
+                              sizeof(regular_token_info_prefix) - 1) != 0) {
+    return -1;
+  }
+
+  aadlen = crypto_generate_regular_token_aad(aad, remote_addr);
+
+  p = token;
+  *p++ = NGTCP2_CRYPTO_TOKEN_MAGIC_REGULAR;
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&aead_ctx, &aead, key, ivlen) != 0) {
+    return -1;
+  }
+
+  rv = ngtcp2_crypto_encrypt(p, &aead, &aead_ctx, plaintext, plaintextlen, iv,
+                             ivlen, aad, aadlen);
+
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  if (rv != 0) {
+    return -1;
+  }
+
+  p += plaintextlen + aead.max_overhead;
+  memcpy(p, rand_data, sizeof(rand_data));
+  p += sizeof(rand_data);
+
+  return p - token;
+}
+
+int ngtcp2_crypto_verify_regular_token(const uint8_t *token, size_t tokenlen,
+                                       const uint8_t *secret, size_t secretlen,
+                                       const ngtcp2_sockaddr *remote_addr,
+                                       ngtcp2_socklen remote_addrlen,
+                                       ngtcp2_duration timeout,
+                                       ngtcp2_tstamp ts) {
+  uint8_t plaintext[sizeof(ngtcp2_tstamp)];
+  uint8_t key[32];
+  uint8_t iv[32];
+  size_t keylen;
+  size_t ivlen;
+  ngtcp2_crypto_aead_ctx aead_ctx;
+  ngtcp2_crypto_aead aead;
+  ngtcp2_crypto_md md;
+  uint8_t aad[sizeof(ngtcp2_sockaddr_in6)];
+  size_t aadlen;
+  const uint8_t *rand_data;
+  const uint8_t *ciphertext;
+  size_t ciphertextlen;
+  int rv;
+  ngtcp2_tstamp gen_ts;
+  (void)remote_addrlen;
+
+  if (tokenlen != NGTCP2_CRYPTO_MAX_REGULAR_TOKENLEN ||
+      token[0] != NGTCP2_CRYPTO_TOKEN_MAGIC_REGULAR) {
+    return -1;
+  }
+
+  rand_data = token + tokenlen - NGTCP2_CRYPTO_TOKEN_RAND_DATALEN;
+  ciphertext = token + 1;
+  ciphertextlen = tokenlen - 1 - NGTCP2_CRYPTO_TOKEN_RAND_DATALEN;
+
+  ngtcp2_crypto_aead_aes_128_gcm(&aead);
+  ngtcp2_crypto_md_sha256(&md);
+
+  keylen = ngtcp2_crypto_aead_keylen(&aead);
+  ivlen = ngtcp2_crypto_aead_noncelen(&aead);
+
+  if (crypto_derive_token_key(key, keylen, iv, ivlen, &md, secret, secretlen,
+                              rand_data, NGTCP2_CRYPTO_TOKEN_RAND_DATALEN,
+                              regular_token_info_prefix,
+                              sizeof(regular_token_info_prefix) - 1) != 0) {
+    return -1;
+  }
+
+  aadlen = crypto_generate_regular_token_aad(aad, remote_addr);
+
+  if (ngtcp2_crypto_aead_ctx_decrypt_init(&aead_ctx, &aead, key, ivlen) != 0) {
+    return -1;
+  }
+
+  rv = ngtcp2_crypto_decrypt(plaintext, &aead, &aead_ctx, ciphertext,
+                             ciphertextlen, iv, ivlen, aad, aadlen);
+
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  if (rv != 0) {
+    return -1;
+  }
+
+  memcpy(&gen_ts, plaintext, sizeof(gen_ts));
+
+  gen_ts = ngtcp2_ntohl64(gen_ts);
+  if (gen_ts + timeout <= ts) {
+    return -1;
+  }
+
+  return 0;
+}
+
+ngtcp2_ssize ngtcp2_crypto_write_connection_close(
+    uint8_t *dest, size_t destlen, uint32_t version, const ngtcp2_cid *dcid,
+    const ngtcp2_cid *scid, uint64_t error_code, const uint8_t *reason,
+    size_t reasonlen) {
+  uint8_t rx_secret[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t tx_secret[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t initial_secret[NGTCP2_CRYPTO_INITIAL_SECRETLEN];
+  uint8_t tx_key[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  uint8_t tx_iv[NGTCP2_CRYPTO_INITIAL_IVLEN];
+  uint8_t tx_hp_key[NGTCP2_CRYPTO_INITIAL_KEYLEN];
+  ngtcp2_crypto_ctx ctx;
+  ngtcp2_ssize spktlen;
+  ngtcp2_crypto_aead_ctx aead_ctx = {0};
+  ngtcp2_crypto_cipher_ctx hp_ctx = {0};
+
+  ngtcp2_crypto_ctx_initial(&ctx);
+
+  if (ngtcp2_crypto_derive_initial_secrets(version, rx_secret, tx_secret,
+                                           initial_secret, scid,
+                                           NGTCP2_CRYPTO_SIDE_SERVER) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_derive_packet_protection_key(
+          tx_key, tx_iv, tx_hp_key, version, &ctx.aead, &ctx.md, tx_secret,
+          NGTCP2_CRYPTO_INITIAL_SECRETLEN) != 0) {
+    return -1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&aead_ctx, &ctx.aead, tx_key,
+                                          NGTCP2_CRYPTO_INITIAL_IVLEN) != 0) {
+    spktlen = -1;
+    goto end;
+  }
+
+  if (ngtcp2_crypto_cipher_ctx_encrypt_init(&hp_ctx, &ctx.hp, tx_hp_key) != 0) {
+    spktlen = -1;
+    goto end;
+  }
+
+  spktlen = ngtcp2_pkt_write_connection_close(
+      dest, destlen, version, dcid, scid, error_code, reason, reasonlen,
+      ngtcp2_crypto_encrypt_cb, &ctx.aead, &aead_ctx, tx_iv,
+      ngtcp2_crypto_hp_mask_cb, &ctx.hp, &hp_ctx);
+  if (spktlen < 0) {
+    spktlen = -1;
+  }
+
+end:
+  ngtcp2_crypto_cipher_ctx_free(&hp_ctx);
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  return spktlen;
+}
+
+ngtcp2_ssize ngtcp2_crypto_write_retry(uint8_t *dest, size_t destlen,
+                                       uint32_t version, const ngtcp2_cid *dcid,
+                                       const ngtcp2_cid *scid,
+                                       const ngtcp2_cid *odcid,
+                                       const uint8_t *token, size_t tokenlen) {
+  ngtcp2_crypto_aead aead;
+  ngtcp2_ssize spktlen;
+  ngtcp2_crypto_aead_ctx aead_ctx = {0};
+  const uint8_t *key;
+  size_t noncelen;
+
+  ngtcp2_crypto_aead_retry(&aead);
+
+  switch (version) {
+  case NGTCP2_PROTO_VER_V1:
+    key = (const uint8_t *)NGTCP2_RETRY_KEY_V1;
+    noncelen = sizeof(NGTCP2_RETRY_NONCE_V1) - 1;
+    break;
+  case NGTCP2_PROTO_VER_V2:
+    key = (const uint8_t *)NGTCP2_RETRY_KEY_V2;
+    noncelen = sizeof(NGTCP2_RETRY_NONCE_V2) - 1;
+    break;
+  default:
+    key = (const uint8_t *)NGTCP2_RETRY_KEY_DRAFT;
+    noncelen = sizeof(NGTCP2_RETRY_NONCE_DRAFT) - 1;
+  }
+
+  if (ngtcp2_crypto_aead_ctx_encrypt_init(&aead_ctx, &aead, key, noncelen) !=
+      0) {
+    return -1;
+  }
+
+  spktlen = ngtcp2_pkt_write_retry(dest, destlen, version, dcid, scid, odcid,
+                                   token, tokenlen, ngtcp2_crypto_encrypt_cb,
+                                   &aead, &aead_ctx);
+  if (spktlen < 0) {
+    spktlen = -1;
+  }
+
+  ngtcp2_crypto_aead_ctx_free(&aead_ctx);
+
+  return spktlen;
+}
+
+int ngtcp2_crypto_client_initial_cb(ngtcp2_conn *conn, void *user_data) {
+  const ngtcp2_cid *dcid = ngtcp2_conn_get_dcid(conn);
+  void *tls = ngtcp2_conn_get_tls_native_handle(conn);
+  (void)user_data;
+
+  if (ngtcp2_crypto_derive_and_install_initial_key(
+          conn, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+          ngtcp2_conn_get_client_chosen_version(conn), dcid) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  if (crypto_set_local_transport_params(conn, tls) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  if (ngtcp2_crypto_read_write_crypto_data(conn, NGTCP2_CRYPTO_LEVEL_INITIAL,
+                                           NULL, 0) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_recv_retry_cb(ngtcp2_conn *conn, const ngtcp2_pkt_hd *hd,
+                                void *user_data) {
+  (void)user_data;
+
+  if (ngtcp2_crypto_derive_and_install_initial_key(
+          conn, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+          ngtcp2_conn_get_client_chosen_version(conn), &hd->scid) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_recv_client_initial_cb(ngtcp2_conn *conn,
+                                         const ngtcp2_cid *dcid,
+                                         void *user_data) {
+  (void)user_data;
+
+  if (ngtcp2_crypto_derive_and_install_initial_key(
+          conn, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+          ngtcp2_conn_get_client_chosen_version(conn), dcid) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  return 0;
+}
+
+int ngtcp2_crypto_version_negotiation_cb(ngtcp2_conn *conn, uint32_t version,
+                                         const ngtcp2_cid *client_dcid,
+                                         void *user_data) {
+  (void)user_data;
+
+  if (ngtcp2_crypto_derive_and_install_vneg_initial_key(
+          conn, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, version,
+          client_dcid) != 0) {
+    return NGTCP2_ERR_CALLBACK_FAILURE;
+  }
+
+  return 0;
+}
+
+void ngtcp2_crypto_delete_crypto_aead_ctx_cb(ngtcp2_conn *conn,
+                                             ngtcp2_crypto_aead_ctx *aead_ctx,
+                                             void *user_data) {
+  (void)conn;
+  (void)user_data;
+
+  ngtcp2_crypto_aead_ctx_free(aead_ctx);
+}
+
+void ngtcp2_crypto_delete_crypto_cipher_ctx_cb(
+    ngtcp2_conn *conn, ngtcp2_crypto_cipher_ctx *cipher_ctx, void *user_data) {
+  (void)conn;
+  (void)user_data;
+
+  ngtcp2_crypto_cipher_ctx_free(cipher_ctx);
+}
+
+int ngtcp2_crypto_recv_crypto_data_cb(ngtcp2_conn *conn,
+                                      ngtcp2_crypto_level crypto_level,
+                                      uint64_t offset, const uint8_t *data,
+                                      size_t datalen, void *user_data) {
+  int rv;
+  (void)offset;
+  (void)user_data;
+
+  if (ngtcp2_crypto_read_write_crypto_data(conn, crypto_level, data, datalen) !=
+      0) {
+    rv = ngtcp2_conn_get_tls_error(conn);
+    if (rv) {
+      return rv;
+    }
+    return NGTCP2_ERR_CRYPTO;
+  }
+
+  return 0;
+}
diff --git a/src/contrib/libngtcp2/ngtcp2/crypto/shared.h b/src/contrib/libngtcp2/ngtcp2/crypto/shared.h
new file mode 100644
index 0000000..c7690c1
--- /dev/null
+++ b/src/contrib/libngtcp2/ngtcp2/crypto/shared.h
@@ -0,0 +1,350 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2019 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef NGTCP2_SHARED_H
+#define NGTCP2_SHARED_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <ngtcp2/ngtcp2_crypto.h>
+
+/**
+ * @macro
+ *
+ * :macro:`NGTCP2_INITIAL_SALT_DRAFT` is a salt value which is used to
+ * derive initial secret.  It is used for QUIC draft versions.
+ */
+#define NGTCP2_INITIAL_SALT_DRAFT                                              \
+  "\xaf\xbf\xec\x28\x99\x93\xd2\x4c\x9e\x97\x86\xf1\x9c\x61\x11\xe0\x43\x90"   \
+  "\xa8\x99"
+
+/**
+ * @macro
+ *
+ * :macro:`NGTCP2_INITIAL_SALT_V1` is a salt value which is used to
+ * derive initial secret.  It is used for QUIC v1.
+ */
+#define NGTCP2_INITIAL_SALT_V1                                                 \
+  "\x38\x76\x2c\xf7\xf5\x59\x34\xb3\x4d\x17\x9a\xe6\xa4\xc8\x0c\xad\xcc\xbb"   \
+  "\x7f\x0a"
+
+/**
+ * @macro
+ *
+ * :macro:`NGTCP2_INITIAL_SALT_V2` is a salt value which is used to
+ * derive initial secret.  It is used for QUIC v2.
+ */
+#define NGTCP2_INITIAL_SALT_V2                                                 \
+  "\x0d\xed\xe3\xde\xf7\x00\xa6\xdb\x81\x93\x81\xbe\x6e\x26\x9d\xcb\xf9\xbd"   \
+  "\x2e\xd9"
+
+/* Maximum key usage (encryption) limits */
+#define NGTCP2_CRYPTO_MAX_ENCRYPTION_AES_GCM (1ULL << 23)
+#define NGTCP2_CRYPTO_MAX_ENCRYPTION_CHACHA20_POLY1305 (1ULL << 62)
+#define NGTCP2_CRYPTO_MAX_ENCRYPTION_AES_CCM (2965820ULL)
+
+/* Maximum authentication failure (decryption) limits during the
+   lifetime of a connection. */
+#define NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_AES_GCM (1ULL << 52)
+#define NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_CHACHA20_POLY1305 (1ULL << 36)
+#define NGTCP2_CRYPTO_MAX_DECRYPTION_FAILURE_AES_CCM (2965820ULL)
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_ctx_initial` initializes |ctx| for Initial packet
+ * encryption and decryption.
+ */
+ngtcp2_crypto_ctx *ngtcp2_crypto_ctx_initial(ngtcp2_crypto_ctx *ctx);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_aead_init` initializes |aead| with the provided
+ * |aead_native_handle| which is an underlying AEAD object.
+ *
+ * If libngtcp2_crypto_openssl is linked, |aead_native_handle| must be
+ * a pointer to EVP_CIPHER.
+ *
+ * If libngtcp2_crypto_gnutls is linked, |aead_native_handle| must be
+ * gnutls_cipher_algorithm_t casted to ``void *``.
+ *
+ * If libngtcp2_crypto_boringssl is linked, |aead_native_handle| must
+ * be a pointer to EVP_AEAD.
+ */
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_init(ngtcp2_crypto_aead *aead,
+                                            void *aead_native_handle);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_aead_retry` initializes |aead| with the AEAD cipher
+ * AEAD_AES_128_GCM for Retry packet integrity protection.
+ */
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_retry(ngtcp2_crypto_aead *aead);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_derive_initial_secrets` derives initial secrets.
+ * |rx_secret| and |tx_secret| must point to the buffer of at least 32
+ * bytes capacity.  rx for read and tx for write.  This function
+ * writes rx and tx secrets into |rx_secret| and |tx_secret|
+ * respectively.  The length of secret is 32 bytes long.
+ * |client_dcid| is the destination connection ID in first Initial
+ * packet of client.  If |initial_secret| is not NULL, the initial
+ * secret is written to it.  It must point to the buffer which has at
+ * least 32 bytes capacity.  The initial secret is 32 bytes long.
+ * |side| specifies the side of application.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_derive_initial_secrets(uint32_t version, uint8_t *rx_secret,
+                                         uint8_t *tx_secret,
+                                         uint8_t *initial_secret,
+                                         const ngtcp2_cid *client_dcid,
+                                         ngtcp2_crypto_side side);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_derive_packet_protection_key` derives packet
+ * protection key.  This function writes packet protection key into
+ * the buffer pointed by |key|.  The length of derived key is
+ * `ngtcp2_crypto_aead_keylen(aead) <ngtcp2_crypto_aead_keylen>`
+ * bytes.  |key| must have enough capacity to store the key.  This
+ * function writes packet protection IV into |iv|.  The length of
+ * derived IV is `ngtcp2_crypto_packet_protection_ivlen(aead)
+ * <ngtcp2_crypto_packet_protection_ivlen>` bytes.  |iv| must have
+ * enough capacity to store the IV.
+ *
+ * If |hp| is not NULL, this function also derives packet header
+ * protection key and writes the key into the buffer pointed by |hp|.
+ * The length of derived key is `ngtcp2_crypto_aead_keylen(aead)
+ * <ngtcp2_crypto_aead_keylen>` bytes.  |hp|, if not NULL, must have
+ * enough capacity to store the key.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_derive_packet_protection_key(uint8_t *key, uint8_t *iv,
+                                               uint8_t *hp, uint32_t version,
+                                               const ngtcp2_crypto_aead *aead,
+                                               const ngtcp2_crypto_md *md,
+                                               const uint8_t *secret,
+                                               size_t secretlen);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_update_traffic_secret` derives the next generation
+ * of the traffic secret.  |secret| specifies the current secret and
+ * its length is given in |secretlen|.  The length of new key is the
+ * same as the current key.  This function writes new key into the
+ * buffer pointed by |dest|.  |dest| must have the enough capacity to
+ * store the new key.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_update_traffic_secret(uint8_t *dest,
+                                        const ngtcp2_crypto_md *md,
+                                        const uint8_t *secret,
+                                        size_t secretlen);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_set_local_transport_params` sets QUIC transport
+ * parameter, which is encoded in wire format and stored in the buffer
+ * pointed by |buf| of length |len|, to the native handle |tls|.
+ *
+ * |tls| points to a implementation dependent TLS session object.  If
+ * libngtcp2_crypto_openssl is linked, |tls| must be a pointer to SSL
+ * object.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_set_local_transport_params(void *tls, const uint8_t *buf,
+                                             size_t len);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_set_remote_transport_params` retrieves a remote QUIC
+ * transport parameters from |tls| and sets it to |conn| using
+ * `ngtcp2_conn_set_remote_transport_params`.
+ *
+ * |tls| points to a implementation dependent TLS session object.  If
+ * libngtcp2_crypto_openssl is linked, |tls| must be a pointer to SSL
+ * object.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_set_remote_transport_params(ngtcp2_conn *conn, void *tls);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_derive_and_install_initial_key` derives initial
+ * keying materials and installs keys to |conn|.
+ *
+ * If |rx_secret| is not NULL, the secret for decryption is written to
+ * the buffer pointed by |rx_secret|.  The length of secret is 32
+ * bytes, and |rx_secret| must point to the buffer which has enough
+ * capacity.
+ *
+ * If |tx_secret| is not NULL, the secret for encryption is written to
+ * the buffer pointed by |tx_secret|.  The length of secret is 32
+ * bytes, and |tx_secret| must point to the buffer which has enough
+ * capacity.
+ *
+ * If |initial_secret| is not NULL, the initial secret is written to
+ * the buffer pointed by |initial_secret|.  The length of secret is 32
+ * bytes, and |initial_secret| must point to the buffer which has
+ * enough capacity.
+ *
+ * |client_dcid| is the destination connection ID in first Initial
+ * packet of client.
+ *
+ * If |rx_key| is not NULL, the derived packet protection key for
+ * decryption is written to the buffer pointed by |rx_key|.  If
+ * |rx_iv| is not NULL, the derived packet protection IV for
+ * decryption is written to the buffer pointed by |rx_iv|.  If |rx_hp|
+ * is not NULL, the derived header protection key for decryption is
+ * written to the buffer pointed by |rx_hp|.
+ *
+ * If |tx_key| is not NULL, the derived packet protection key for
+ * encryption is written to the buffer pointed by |tx_key|.  If
+ * |tx_iv| is not NULL, the derived packet protection IV for
+ * encryption is written to the buffer pointed by |tx_iv|.  If |tx_hp|
+ * is not NULL, the derived header protection key for encryption is
+ * written to the buffer pointed by |tx_hp|.
+ *
+ * The length of packet protection key and header protection key is 16
+ * bytes long.  The length of packet protection IV is 12 bytes long.
+ *
+ * This function calls `ngtcp2_conn_set_initial_crypto_ctx` to set
+ * initial AEAD and message digest algorithm.  After the successful
+ * call of this function, application can use
+ * `ngtcp2_conn_get_initial_crypto_ctx` to get the object.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_derive_and_install_initial_key(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    uint8_t *initial_secret, uint8_t *rx_key, uint8_t *rx_iv, uint8_t *rx_hp,
+    uint8_t *tx_key, uint8_t *tx_iv, uint8_t *tx_hp, uint32_t version,
+    const ngtcp2_cid *client_dcid);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_derive_and_install_vneg_initial_key` derives initial
+ * keying materials and installs keys to |conn|.  This function is
+ * dedicated to install keys for |version| which is negotiated, or
+ * being negotiated.
+ *
+ * If |rx_secret| is not NULL, the secret for decryption is written to
+ * the buffer pointed by |rx_secret|.  The length of secret is 32
+ * bytes, and |rx_secret| must point to the buffer which has enough
+ * capacity.
+ *
+ * If |tx_secret| is not NULL, the secret for encryption is written to
+ * the buffer pointed by |tx_secret|.  The length of secret is 32
+ * bytes, and |tx_secret| must point to the buffer which has enough
+ * capacity.
+ *
+ * If |initial_secret| is not NULL, the initial secret is written to
+ * the buffer pointed by |initial_secret|.  The length of secret is 32
+ * bytes, and |initial_secret| must point to the buffer which has
+ * enough capacity.
+ *
+ * |client_dcid| is the destination connection ID in first Initial
+ * packet of client.
+ *
+ * If |rx_key| is not NULL, the derived packet protection key for
+ * decryption is written to the buffer pointed by |rx_key|.  If
+ * |rx_iv| is not NULL, the derived packet protection IV for
+ * decryption is written to the buffer pointed by |rx_iv|.  If |rx_hp|
+ * is not NULL, the derived header protection key for decryption is
+ * written to the buffer pointed by |rx_hp|.
+ *
+ * If |tx_key| is not NULL, the derived packet protection key for
+ * encryption is written to the buffer pointed by |tx_key|.  If
+ * |tx_iv| is not NULL, the derived packet protection IV for
+ * encryption is written to the buffer pointed by |tx_iv|.  If |tx_hp|
+ * is not NULL, the derived header protection key for encryption is
+ * written to the buffer pointed by |tx_hp|.
+ *
+ * The length of packet protection key and header protection key is 16
+ * bytes long.  The length of packet protection IV is 12 bytes long.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_derive_and_install_vneg_initial_key(
+    ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret,
+    uint8_t *initial_secret, uint8_t *rx_key, uint8_t *rx_iv, uint8_t *rx_hp,
+    uint8_t *tx_key, uint8_t *tx_iv, uint8_t *tx_hp, uint32_t version,
+    const ngtcp2_cid *client_dcid);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_cipher_ctx_encrypt_init` initializes |cipher_ctx|
+ * with new cipher context object for encryption which is constructed
+ * to use |key| as encryption key.  |cipher| specifies cipher to use.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_cipher_ctx_encrypt_init(ngtcp2_crypto_cipher_ctx *cipher_ctx,
+                                          const ngtcp2_crypto_cipher *cipher,
+                                          const uint8_t *key);
+
+/**
+ * @function
+ *
+ * `ngtcp2_crypto_cipher_ctx_free` frees up resources used by
+ * |cipher_ctx|.  This function does not free the memory pointed by
+ * |cipher_ctx| itself.
+ */
+void ngtcp2_crypto_cipher_ctx_free(ngtcp2_crypto_cipher_ctx *cipher_ctx);
+
+/*
+ * `ngtcp2_crypto_md_sha256` initializes |md| with SHA256 message
+ * digest algorithm and returns |md|.
+ */
+ngtcp2_crypto_md *ngtcp2_crypto_md_sha256(ngtcp2_crypto_md *md);
+
+ngtcp2_crypto_aead *ngtcp2_crypto_aead_aes_128_gcm(ngtcp2_crypto_aead *aead);
+
+/*
+ * `ngtcp2_crypto_random` writes cryptographically-secure random
+ * |datalen| bytes into the buffer pointed by |data|.
+ *
+ * This function returns 0 if it succeeds, or -1.
+ */
+int ngtcp2_crypto_random(uint8_t *data, size_t datalen);
+
+#endif /* NGTCP2_SHARED_H */