Revert "external/boringssl: Sync to 897a2ca3f184b34278641138c726ef902ab1fab2."

This reverts commit a769e3be7b5b02e3a0ee4043b6642ab0361a1420.

Reason for revert: Breaks x86 builds: b/194262305

Change-Id: I9074b7d01972b3f1162eb3ece0a591077d0b3451

1 files changed, 0 insertions, 1175 deletions

diff --git a/src/ssl/encrypted_client_hello.cc b/src/ssl/encrypted_client_hello.cc
deleted file mode 100644
index b70f66c1..00000000
--- a/src/ssl/encrypted_client_hello.cc
+++ /dev/null
@@ -1,1175 +0,0 @@
-/* Copyright (c) 2021, Google Inc.
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
- * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
- * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
- * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
-
-#include <openssl/ssl.h>
-
-#include <assert.h>
-#include <string.h>
-
-#include <algorithm>
-#include <utility>
-
-#include <openssl/aead.h>
-#include <openssl/bytestring.h>
-#include <openssl/curve25519.h>
-#include <openssl/err.h>
-#include <openssl/hkdf.h>
-#include <openssl/hpke.h>
-#include <openssl/rand.h>
-
-#include "internal.h"
-
-
-#if defined(OPENSSL_MSAN)
-#define NO_SANITIZE_MEMORY __attribute__((no_sanitize("memory")))
-#else
-#define NO_SANITIZE_MEMORY
-#endif
-
-BSSL_NAMESPACE_BEGIN
-
-// ECH reuses the extension code point for the version number.
-static constexpr uint16_t kECHConfigVersion =
-    TLSEXT_TYPE_encrypted_client_hello;
-
-static const decltype(&EVP_hpke_aes_128_gcm) kSupportedAEADs[] = {
-    &EVP_hpke_aes_128_gcm,
-    &EVP_hpke_aes_256_gcm,
-    &EVP_hpke_chacha20_poly1305,
-};
-
-static const EVP_HPKE_AEAD *get_ech_aead(uint16_t aead_id) {
-  for (const auto aead_func : kSupportedAEADs) {
-    const EVP_HPKE_AEAD *aead = aead_func();
-    if (aead_id == EVP_HPKE_AEAD_id(aead)) {
-      return aead;
-    }
-  }
-  return nullptr;
-}
-
-// ssl_client_hello_write_without_extensions serializes |client_hello| into
-// |out|, omitting the length-prefixed extensions. It serializes individual
-// fields, starting with |client_hello->version|, and ignores the
-// |client_hello->client_hello| field. It returns true on success and false on
-// failure.
-static bool ssl_client_hello_write_without_extensions(
-    const SSL_CLIENT_HELLO *client_hello, CBB *out) {
-  CBB cbb;
-  if (!CBB_add_u16(out, client_hello->version) ||
-      !CBB_add_bytes(out, client_hello->random, client_hello->random_len) ||
-      !CBB_add_u8_length_prefixed(out, &cbb) ||
-      !CBB_add_bytes(&cbb, client_hello->session_id,
-                     client_hello->session_id_len) ||
-      !CBB_add_u16_length_prefixed(out, &cbb) ||
-      !CBB_add_bytes(&cbb, client_hello->cipher_suites,
-                     client_hello->cipher_suites_len) ||
-      !CBB_add_u8_length_prefixed(out, &cbb) ||
-      !CBB_add_bytes(&cbb, client_hello->compression_methods,
-                     client_hello->compression_methods_len) ||
-      !CBB_flush(out)) {
-    return false;
-  }
-  return true;
-}
-
-bool ssl_decode_client_hello_inner(
-    SSL *ssl, uint8_t *out_alert, Array<uint8_t> *out_client_hello_inner,
-    Span<const uint8_t> encoded_client_hello_inner,
-    const SSL_CLIENT_HELLO *client_hello_outer) {
-  SSL_CLIENT_HELLO client_hello_inner;
-  if (!ssl_client_hello_init(ssl, &client_hello_inner,
-                             encoded_client_hello_inner)) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-  // TLS 1.3 ClientHellos must have extensions, and EncodedClientHelloInners use
-  // ClientHelloOuter's session_id.
-  if (client_hello_inner.extensions_len == 0 ||
-      client_hello_inner.session_id_len != 0) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-  client_hello_inner.session_id = client_hello_outer->session_id;
-  client_hello_inner.session_id_len = client_hello_outer->session_id_len;
-
-  // Begin serializing a message containing the ClientHelloInner in |cbb|.
-  ScopedCBB cbb;
-  CBB body, extensions;
-  if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CLIENT_HELLO) ||
-      !ssl_client_hello_write_without_extensions(&client_hello_inner, &body) ||
-      !CBB_add_u16_length_prefixed(&body, &extensions)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return false;
-  }
-
-  // Sort the extensions in ClientHelloOuter, so ech_outer_extensions may be
-  // processed in O(n*log(n)) time, rather than O(n^2).
-  struct Extension {
-    uint16_t extension = 0;
-    Span<const uint8_t> body;
-    bool copied = false;
-  };
-
-  // MSan's libc interceptors do not handle |bsearch|. See b/182583130.
-  auto compare_extension = [](const void *a, const void *b)
-                               NO_SANITIZE_MEMORY -> int {
-    const Extension *extension_a = reinterpret_cast<const Extension *>(a);
-    const Extension *extension_b = reinterpret_cast<const Extension *>(b);
-    if (extension_a->extension < extension_b->extension) {
-      return -1;
-    } else if (extension_a->extension > extension_b->extension) {
-      return 1;
-    }
-    return 0;
-  };
-  GrowableArray<Extension> sorted_extensions;
-  CBS unsorted_extensions(MakeConstSpan(client_hello_outer->extensions,
-                                        client_hello_outer->extensions_len));
-  while (CBS_len(&unsorted_extensions) > 0) {
-    Extension extension;
-    CBS extension_body;
-    if (!CBS_get_u16(&unsorted_extensions, &extension.extension) ||
-        !CBS_get_u16_length_prefixed(&unsorted_extensions, &extension_body)) {
-      OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-      return false;
-    }
-    extension.body = extension_body;
-    if (!sorted_extensions.Push(extension)) {
-      return false;
-    }
-  }
-  qsort(sorted_extensions.data(), sorted_extensions.size(), sizeof(Extension),
-        compare_extension);
-
-  // Copy extensions from |client_hello_inner|, expanding ech_outer_extensions.
-  CBS inner_extensions(MakeConstSpan(client_hello_inner.extensions,
-                                     client_hello_inner.extensions_len));
-  while (CBS_len(&inner_extensions) > 0) {
-    uint16_t extension_id;
-    CBS extension_body;
-    if (!CBS_get_u16(&inner_extensions, &extension_id) ||
-        !CBS_get_u16_length_prefixed(&inner_extensions, &extension_body)) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    if (extension_id != TLSEXT_TYPE_ech_outer_extensions) {
-      if (!CBB_add_u16(&extensions, extension_id) ||
-          !CBB_add_u16(&extensions, CBS_len(&extension_body)) ||
-          !CBB_add_bytes(&extensions, CBS_data(&extension_body),
-                         CBS_len(&extension_body))) {
-        OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-        return false;
-      }
-      continue;
-    }
-
-    // Replace ech_outer_extensions with the corresponding outer extensions.
-    CBS outer_extensions;
-    if (!CBS_get_u8_length_prefixed(&extension_body, &outer_extensions) ||
-        CBS_len(&extension_body) != 0) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    while (CBS_len(&outer_extensions) > 0) {
-      uint16_t extension_needed;
-      if (!CBS_get_u16(&outer_extensions, &extension_needed)) {
-        OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-        return false;
-      }
-      if (extension_needed == TLSEXT_TYPE_encrypted_client_hello) {
-        *out_alert = SSL_AD_ILLEGAL_PARAMETER;
-        OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-        return false;
-      }
-      // Find the referenced extension.
-      Extension key;
-      key.extension = extension_needed;
-      Extension *result = reinterpret_cast<Extension *>(
-          bsearch(&key, sorted_extensions.data(), sorted_extensions.size(),
-                  sizeof(Extension), compare_extension));
-      if (result == nullptr) {
-        *out_alert = SSL_AD_ILLEGAL_PARAMETER;
-        OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-        return false;
-      }
-
-      // Extensions may be referenced at most once, to bound the result size.
-      if (result->copied) {
-        *out_alert = SSL_AD_ILLEGAL_PARAMETER;
-        OPENSSL_PUT_ERROR(SSL, SSL_R_DUPLICATE_EXTENSION);
-        return false;
-      }
-      result->copied = true;
-
-      if (!CBB_add_u16(&extensions, extension_needed) ||
-          !CBB_add_u16(&extensions, result->body.size()) ||
-          !CBB_add_bytes(&extensions, result->body.data(),
-                         result->body.size())) {
-        OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-        return false;
-      }
-    }
-  }
-  if (!CBB_flush(&body)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return false;
-  }
-
-  // See https://github.com/tlswg/draft-ietf-tls-esni/pull/411
-  CBS extension;
-  if (!ssl_client_hello_init(ssl, &client_hello_inner,
-                             MakeConstSpan(CBB_data(&body), CBB_len(&body))) ||
-      !ssl_client_hello_get_extension(&client_hello_inner, &extension,
-                                      TLSEXT_TYPE_ech_is_inner) ||
-      CBS_len(&extension) != 0 ||
-      ssl_client_hello_get_extension(&client_hello_inner, &extension,
-                                     TLSEXT_TYPE_encrypted_client_hello) ||
-      !ssl_client_hello_get_extension(&client_hello_inner, &extension,
-                                      TLSEXT_TYPE_supported_versions)) {
-    *out_alert = SSL_AD_ILLEGAL_PARAMETER;
-    OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_CLIENT_HELLO_INNER);
-    return false;
-  }
-  // Parse supported_versions and reject TLS versions prior to TLS 1.3. Older
-  // versions are incompatible with ECH.
-  CBS versions;
-  if (!CBS_get_u8_length_prefixed(&extension, &versions) ||
-      CBS_len(&extension) != 0 ||  //
-      CBS_len(&versions) == 0) {
-    *out_alert = SSL_AD_DECODE_ERROR;
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-  while (CBS_len(&versions) != 0) {
-    uint16_t version;
-    if (!CBS_get_u16(&versions, &version)) {
-      *out_alert = SSL_AD_DECODE_ERROR;
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    if (version == SSL3_VERSION || version == TLS1_VERSION ||
-        version == TLS1_1_VERSION || version == TLS1_2_VERSION ||
-        version == DTLS1_VERSION || version == DTLS1_2_VERSION) {
-      *out_alert = SSL_AD_ILLEGAL_PARAMETER;
-      OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_CLIENT_HELLO_INNER);
-      return false;
-    }
-  }
-
-  if (!ssl->method->finish_message(ssl, cbb.get(), out_client_hello_inner)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return false;
-  }
-  return true;
-}
-
-bool ssl_client_hello_decrypt(
-    EVP_HPKE_CTX *hpke_ctx, Array<uint8_t> *out_encoded_client_hello_inner,
-    bool *out_is_decrypt_error, const SSL_CLIENT_HELLO *client_hello_outer,
-    uint16_t kdf_id, uint16_t aead_id, const uint8_t config_id,
-    Span<const uint8_t> enc, Span<const uint8_t> payload) {
-  *out_is_decrypt_error = false;
-
-  // Compute the ClientHello portion of the ClientHelloOuterAAD value. See
-  // draft-ietf-tls-esni-10, section 5.2.
-  ScopedCBB aad;
-  CBB enc_cbb, outer_hello_cbb, extensions_cbb;
-  if (!CBB_init(aad.get(), 256) ||
-      !CBB_add_u16(aad.get(), kdf_id) ||
-      !CBB_add_u16(aad.get(), aead_id) ||
-      !CBB_add_u8(aad.get(), config_id) ||
-      !CBB_add_u16_length_prefixed(aad.get(), &enc_cbb) ||
-      !CBB_add_bytes(&enc_cbb, enc.data(), enc.size()) ||
-      !CBB_add_u24_length_prefixed(aad.get(), &outer_hello_cbb) ||
-      !ssl_client_hello_write_without_extensions(client_hello_outer,
-                                                 &outer_hello_cbb) ||
-      !CBB_add_u16_length_prefixed(&outer_hello_cbb, &extensions_cbb)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return false;
-  }
-
-  CBS extensions(MakeConstSpan(client_hello_outer->extensions,
-                               client_hello_outer->extensions_len));
-  while (CBS_len(&extensions) > 0) {
-    uint16_t extension_id;
-    CBS extension_body;
-    if (!CBS_get_u16(&extensions, &extension_id) ||
-        !CBS_get_u16_length_prefixed(&extensions, &extension_body)) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    if (extension_id == TLSEXT_TYPE_encrypted_client_hello) {
-      continue;
-    }
-    if (!CBB_add_u16(&extensions_cbb, extension_id) ||
-        !CBB_add_u16(&extensions_cbb, CBS_len(&extension_body)) ||
-        !CBB_add_bytes(&extensions_cbb, CBS_data(&extension_body),
-                       CBS_len(&extension_body))) {
-      OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-      return false;
-    }
-  }
-  if (!CBB_flush(aad.get())) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return false;
-  }
-
-#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
-  // In fuzzer mode, disable encryption to improve coverage. We reserve a short
-  // input to signal decryption failure, so the fuzzer can explore fallback to
-  // ClientHelloOuter.
-  const uint8_t kBadPayload[] = {0xff};
-  if (payload == kBadPayload) {
-    *out_is_decrypt_error = true;
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED);
-    return false;
-  }
-  if (!out_encoded_client_hello_inner->CopyFrom(payload)) {
-    return false;
-  }
-#else
-  // Attempt to decrypt into |out_encoded_client_hello_inner|.
-  if (!out_encoded_client_hello_inner->Init(payload.size())) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return false;
-  }
-  size_t encoded_client_hello_inner_len;
-  if (!EVP_HPKE_CTX_open(hpke_ctx, out_encoded_client_hello_inner->data(),
-                         &encoded_client_hello_inner_len,
-                         out_encoded_client_hello_inner->size(), payload.data(),
-                         payload.size(), CBB_data(aad.get()),
-                         CBB_len(aad.get()))) {
-    *out_is_decrypt_error = true;
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED);
-    return false;
-  }
-  out_encoded_client_hello_inner->Shrink(encoded_client_hello_inner_len);
-#endif
-  return true;
-}
-
-static bool parse_ipv4_number(Span<const uint8_t> in, uint32_t *out) {
-  // See https://url.spec.whatwg.org/#ipv4-number-parser.
-  uint32_t base = 10;
-  if (in.size() >= 2 && in[0] == '0' && (in[1] == 'x' || in[1] == 'X')) {
-    in = in.subspan(2);
-    base = 16;
-  } else if (in.size() >= 1 && in[0] == '0') {
-    in = in.subspan(1);
-    base = 8;
-  }
-  *out = 0;
-  for (uint8_t c : in) {
-    uint32_t d;
-    if ('0' <= c && c <= '9') {
-      d = c - '0';
-    } else if ('a' <= c && c <= 'f') {
-      d = c - 'a' + 10;
-    } else if ('A' <= c && c <= 'F') {
-      d = c - 'A' + 10;
-    } else {
-      return false;
-    }
-    if (d >= base ||
-        *out > UINT32_MAX / base) {
-      return false;
-    }
-    *out *= base;
-    if (*out > UINT32_MAX - d) {
-      return false;
-    }
-    *out += d;
-  }
-  return true;
-}
-
-static bool is_ipv4_address(Span<const uint8_t> in) {
-  // See https://url.spec.whatwg.org/#concept-ipv4-parser
-  uint32_t numbers[4];
-  size_t num_numbers = 0;
-  while (!in.empty()) {
-    if (num_numbers == 4) {
-      // Too many components.
-      return false;
-    }
-    // Find the next dot-separated component.
-    auto dot = std::find(in.begin(), in.end(), '.');
-    if (dot == in.begin()) {
-      // Empty components are not allowed.
-      return false;
-    }
-    Span<const uint8_t> component;
-    if (dot == in.end()) {
-      component = in;
-      in = Span<const uint8_t>();
-    } else {
-      component = in.subspan(0, dot - in.begin());
-      in = in.subspan(dot - in.begin() + 1);  // Skip the dot.
-    }
-    if (!parse_ipv4_number(component, &numbers[num_numbers])) {
-      return false;
-    }
-    num_numbers++;
-  }
-  if (num_numbers == 0) {
-    return false;
-  }
-  for (size_t i = 0; i < num_numbers - 1; i++) {
-    if (numbers[i] > 255) {
-      return false;
-    }
-  }
-  return num_numbers == 1 ||
-         numbers[num_numbers - 1] < 1u << (8 * (5 - num_numbers));
-}
-
-bool ssl_is_valid_ech_public_name(Span<const uint8_t> public_name) {
-  // See draft-ietf-tls-esni-11, Section 4 and RFC5890, Section 2.3.1. The
-  // public name must be a dot-separated sequence of LDH labels and not begin or
-  // end with a dot.
-  auto copy = public_name;
-  if (copy.empty()) {
-    return false;
-  }
-  while (!copy.empty()) {
-    // Find the next dot-separated component.
-    auto dot = std::find(copy.begin(), copy.end(), '.');
-    Span<const uint8_t> component;
-    if (dot == copy.end()) {
-      component = copy;
-      copy = Span<const uint8_t>();
-    } else {
-      component = copy.subspan(0, dot - copy.begin());
-      copy = copy.subspan(dot - copy.begin() + 1);  // Skip the dot.
-      if (copy.empty()) {
-        // Trailing dots are not allowed.
-        return false;
-      }
-    }
-    // |component| must be a valid LDH label. Checking for empty components also
-    // rejects leading dots.
-    if (component.empty() || component.size() > 63 ||
-        component.front() == '-' || component.back() == '-') {
-      return false;
-    }
-    for (uint8_t c : component) {
-      if (!('a' <= c && c <= 'z') && !('A' <= c && c <= 'Z') &&
-          !('0' <= c && c <= '9') && c != '-') {
-        return false;
-      }
-    }
-  }
-
-  return !is_ipv4_address(public_name);
-}
-
-static bool parse_ech_config(CBS *cbs, ECHConfig *out, bool *out_supported,
-                             bool all_extensions_mandatory) {
-  uint16_t version;
-  CBS orig = *cbs;
-  CBS contents;
-  if (!CBS_get_u16(cbs, &version) ||
-      !CBS_get_u16_length_prefixed(cbs, &contents)) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-
-  if (version != kECHConfigVersion) {
-    *out_supported = false;
-    return true;
-  }
-
-  // Make a copy of the ECHConfig and parse from it, so the results alias into
-  // the saved copy.
-  if (!out->raw.CopyFrom(
-          MakeConstSpan(CBS_data(&orig), CBS_len(&orig) - CBS_len(cbs)))) {
-    return false;
-  }
-
-  CBS ech_config(out->raw);
-  CBS public_name, public_key, cipher_suites, extensions;
-  if (!CBS_skip(&ech_config, 2) || // version
-      !CBS_get_u16_length_prefixed(&ech_config, &contents) ||
-      !CBS_get_u8(&contents, &out->config_id) ||
-      !CBS_get_u16(&contents, &out->kem_id) ||
-      !CBS_get_u16_length_prefixed(&contents, &public_key) ||
-      CBS_len(&public_key) == 0 ||
-      !CBS_get_u16_length_prefixed(&contents, &cipher_suites) ||
-      CBS_len(&cipher_suites) == 0 || CBS_len(&cipher_suites) % 4 != 0 ||
-      !CBS_get_u16(&contents, &out->maximum_name_length) ||
-      !CBS_get_u16_length_prefixed(&contents, &public_name) ||
-      CBS_len(&public_name) == 0 ||
-      !CBS_get_u16_length_prefixed(&contents, &extensions) ||
-      CBS_len(&contents) != 0) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-
-  if (!ssl_is_valid_ech_public_name(public_name)) {
-    // TODO(https://crbug.com/boringssl/275): The draft says ECHConfigs with
-    // invalid public names should be ignored, but LDH syntax failures are
-    // unambiguously invalid.
-    *out_supported = false;
-    return true;
-  }
-
-  out->public_key = public_key;
-  out->public_name = public_name;
-  // This function does not ensure |out->kem_id| and |out->cipher_suites| use
-  // supported algorithms. The caller must do this.
-  out->cipher_suites = cipher_suites;
-
-  bool has_unknown_mandatory_extension = false;
-  while (CBS_len(&extensions) != 0) {
-    uint16_t type;
-    CBS body;
-    if (!CBS_get_u16(&extensions, &type) ||
-        !CBS_get_u16_length_prefixed(&extensions, &body)) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    // We currently do not support any extensions.
-    if (type & 0x8000 || all_extensions_mandatory) {
-      // Extension numbers with the high bit set are mandatory. Continue parsing
-      // to enforce syntax, but we will ultimately ignore this ECHConfig as a
-      // client and reject it as a server.
-      has_unknown_mandatory_extension = true;
-    }
-  }
-
-  *out_supported = !has_unknown_mandatory_extension;
-  return true;
-}
-
-bool ECHServerConfig::Init(Span<const uint8_t> ech_config,
-                           const EVP_HPKE_KEY *key, bool is_retry_config) {
-  is_retry_config_ = is_retry_config;
-
-  // Parse the ECHConfig, rejecting all unsupported parameters and extensions.
-  // Unlike most server options, ECH's server configuration is serialized and
-  // configured in both the server and DNS. If the caller configures an
-  // unsupported parameter, this is a deployment error. To catch these errors,
-  // we fail early.
-  CBS cbs = ech_config;
-  bool supported;
-  if (!parse_ech_config(&cbs, &ech_config_, &supported,
-                        /*all_extensions_mandatory=*/true)) {
-    return false;
-  }
-  if (CBS_len(&cbs) != 0) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return false;
-  }
-  if (!supported) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_ECH_SERVER_CONFIG);
-    return false;
-  }
-
-  CBS cipher_suites = ech_config_.cipher_suites;
-  while (CBS_len(&cipher_suites) > 0) {
-    uint16_t kdf_id, aead_id;
-    if (!CBS_get_u16(&cipher_suites, &kdf_id) ||
-        !CBS_get_u16(&cipher_suites, &aead_id)) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-      return false;
-    }
-    // The server promises to support every option in the ECHConfig, so reject
-    // any unsupported cipher suites.
-    if (kdf_id != EVP_HPKE_HKDF_SHA256 || get_ech_aead(aead_id) == nullptr) {
-      OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_ECH_SERVER_CONFIG);
-      return false;
-    }
-  }
-
-  // Check the public key in the ECHConfig matches |key|.
-  uint8_t expected_public_key[EVP_HPKE_MAX_PUBLIC_KEY_LENGTH];
-  size_t expected_public_key_len;
-  if (!EVP_HPKE_KEY_public_key(key, expected_public_key,
-                               &expected_public_key_len,
-                               sizeof(expected_public_key))) {
-    return false;
-  }
-  if (ech_config_.kem_id != EVP_HPKE_KEM_id(EVP_HPKE_KEY_kem(key)) ||
-      MakeConstSpan(expected_public_key, expected_public_key_len) !=
-          ech_config_.public_key) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_ECH_SERVER_CONFIG_AND_PRIVATE_KEY_MISMATCH);
-    return false;
-  }
-
-  if (!EVP_HPKE_KEY_copy(key_.get(), key)) {
-    return false;
-  }
-
-  return true;
-}
-
-bool ECHServerConfig::SetupContext(EVP_HPKE_CTX *ctx, uint16_t kdf_id,
-                                   uint16_t aead_id,
-                                   Span<const uint8_t> enc) const {
-  // Check the cipher suite is supported by this ECHServerConfig.
-  CBS cbs(ech_config_.cipher_suites);
-  bool cipher_ok = false;
-  while (CBS_len(&cbs) != 0) {
-    uint16_t supported_kdf_id, supported_aead_id;
-    if (!CBS_get_u16(&cbs, &supported_kdf_id) ||
-        !CBS_get_u16(&cbs, &supported_aead_id)) {
-      return false;
-    }
-    if (kdf_id == supported_kdf_id && aead_id == supported_aead_id) {
-      cipher_ok = true;
-      break;
-    }
-  }
-  if (!cipher_ok) {
-    return false;
-  }
-
-  static const uint8_t kInfoLabel[] = "tls ech";
-  ScopedCBB info_cbb;
-  if (!CBB_init(info_cbb.get(), sizeof(kInfoLabel) + ech_config_.raw.size()) ||
-      !CBB_add_bytes(info_cbb.get(), kInfoLabel,
-                     sizeof(kInfoLabel) /* includes trailing NUL */) ||
-      !CBB_add_bytes(info_cbb.get(), ech_config_.raw.data(),
-                     ech_config_.raw.size())) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return false;
-  }
-
-  assert(kdf_id == EVP_HPKE_HKDF_SHA256);
-  assert(get_ech_aead(aead_id) != NULL);
-  return EVP_HPKE_CTX_setup_recipient(
-      ctx, key_.get(), EVP_hpke_hkdf_sha256(), get_ech_aead(aead_id), enc.data(),
-      enc.size(), CBB_data(info_cbb.get()), CBB_len(info_cbb.get()));
-}
-
-bool ssl_is_valid_ech_config_list(Span<const uint8_t> ech_config_list) {
-  CBS cbs = ech_config_list, child;
-  if (!CBS_get_u16_length_prefixed(&cbs, &child) ||  //
-      CBS_len(&child) == 0 ||                        //
-      CBS_len(&cbs) > 0) {
-    return false;
-  }
-  while (CBS_len(&child) > 0) {
-    ECHConfig ech_config;
-    bool supported;
-    if (!parse_ech_config(&child, &ech_config, &supported,
-                          /*all_extensions_mandatory=*/false)) {
-      return false;
-    }
-  }
-  return true;
-}
-
-static bool select_ech_cipher_suite(const EVP_HPKE_KDF **out_kdf,
-                                    const EVP_HPKE_AEAD **out_aead,
-                                    Span<const uint8_t> cipher_suites) {
-  const bool has_aes_hardware = EVP_has_aes_hardware();
-  const EVP_HPKE_AEAD *aead = nullptr;
-  CBS cbs = cipher_suites;
-  while (CBS_len(&cbs) != 0) {
-    uint16_t kdf_id, aead_id;
-    if (!CBS_get_u16(&cbs, &kdf_id) ||  //
-        !CBS_get_u16(&cbs, &aead_id)) {
-      return false;
-    }
-    // Pick the first common cipher suite, but prefer ChaCha20-Poly1305 if we
-    // don't have AES hardware.
-    const EVP_HPKE_AEAD *candidate = get_ech_aead(aead_id);
-    if (kdf_id != EVP_HPKE_HKDF_SHA256 || candidate == nullptr) {
-      continue;
-    }
-    if (aead == nullptr ||
-        (!has_aes_hardware && aead_id == EVP_HPKE_CHACHA20_POLY1305)) {
-      aead = candidate;
-    }
-  }
-  if (aead == nullptr) {
-    return false;
-  }
-
-  *out_kdf = EVP_hpke_hkdf_sha256();
-  *out_aead = aead;
-  return true;
-}
-
-bool ssl_select_ech_config(SSL_HANDSHAKE *hs, Span<uint8_t> out_enc,
-                           size_t *out_enc_len) {
-  *out_enc_len = 0;
-  if (hs->max_version < TLS1_3_VERSION) {
-    // ECH requires TLS 1.3.
-    return true;
-  }
-
-  if (!hs->config->client_ech_config_list.empty()) {
-    CBS cbs = MakeConstSpan(hs->config->client_ech_config_list);
-    CBS child;
-    if (!CBS_get_u16_length_prefixed(&cbs, &child) ||  //
-        CBS_len(&child) == 0 ||                        //
-        CBS_len(&cbs) > 0) {
-      return false;
-    }
-    // Look for the first ECHConfig with supported parameters.
-    while (CBS_len(&child) > 0) {
-      ECHConfig ech_config;
-      bool supported;
-      if (!parse_ech_config(&child, &ech_config, &supported,
-                            /*all_extensions_mandatory=*/false)) {
-        return false;
-      }
-      const EVP_HPKE_KEM *kem = EVP_hpke_x25519_hkdf_sha256();
-      const EVP_HPKE_KDF *kdf;
-      const EVP_HPKE_AEAD *aead;
-      if (supported &&  //
-          ech_config.kem_id == EVP_HPKE_DHKEM_X25519_HKDF_SHA256 &&
-          select_ech_cipher_suite(&kdf, &aead, ech_config.cipher_suites)) {
-        ScopedCBB info;
-        static const uint8_t kInfoLabel[] = "tls ech";  // includes trailing NUL
-        if (!CBB_init(info.get(), sizeof(kInfoLabel) + ech_config.raw.size()) ||
-            !CBB_add_bytes(info.get(), kInfoLabel, sizeof(kInfoLabel)) ||
-            !CBB_add_bytes(info.get(), ech_config.raw.data(),
-                           ech_config.raw.size())) {
-          OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-          return false;
-        }
-
-        if (!EVP_HPKE_CTX_setup_sender(
-                hs->ech_hpke_ctx.get(), out_enc.data(), out_enc_len,
-                out_enc.size(), kem, kdf, aead, ech_config.public_key.data(),
-                ech_config.public_key.size(), CBB_data(info.get()),
-                CBB_len(info.get())) ||
-            !hs->inner_transcript.Init()) {
-          return false;
-        }
-
-        hs->selected_ech_config = MakeUnique<ECHConfig>(std::move(ech_config));
-        return hs->selected_ech_config != nullptr;
-      }
-    }
-  }
-
-  return true;
-}
-
-static size_t aead_overhead(const EVP_HPKE_AEAD *aead) {
-#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
-  // TODO(https://crbug.com/boringssl/275): Having to adjust the overhead
-  // everywhere is tedious. Change fuzzer mode to append a fake tag but still
-  // otherwise be cleartext, refresh corpora, and then inline this function.
-  return 0;
-#else
-  return EVP_AEAD_max_overhead(EVP_HPKE_AEAD_aead(aead));
-#endif
-}
-
-static size_t compute_extension_length(const EVP_HPKE_AEAD *aead,
-                                       size_t enc_len, size_t in_len) {
-  size_t ret = 4;      // HpkeSymmetricCipherSuite cipher_suite
-  ret++;               // uint8 config_id
-  ret += 2 + enc_len;  // opaque enc<1..2^16-1>
-  ret += 2 + in_len + aead_overhead(aead);  // opaque payload<1..2^16-1>
-  return ret;
-}
-
-// random_size returns a random value between |min| and |max|, inclusive.
-static size_t random_size(size_t min, size_t max) {
-  assert(min < max);
-  size_t value;
-  RAND_bytes(reinterpret_cast<uint8_t *>(&value), sizeof(value));
-  return value % (max - min + 1) + min;
-}
-
-static bool setup_ech_grease(SSL_HANDSHAKE *hs) {
-  assert(!hs->selected_ech_config);
-  if (hs->max_version < TLS1_3_VERSION || !hs->config->ech_grease_enabled) {
-    return true;
-  }
-
-  const uint16_t kdf_id = EVP_HPKE_HKDF_SHA256;
-  const EVP_HPKE_AEAD *aead = EVP_has_aes_hardware()
-                                  ? EVP_hpke_aes_128_gcm()
-                                  : EVP_hpke_chacha20_poly1305();
-  static_assert(ssl_grease_ech_config_id < sizeof(hs->grease_seed),
-                "hs->grease_seed is too small");
-  uint8_t config_id = hs->grease_seed[ssl_grease_ech_config_id];
-
-  uint8_t enc[X25519_PUBLIC_VALUE_LEN];
-  uint8_t private_key_unused[X25519_PRIVATE_KEY_LEN];
-  X25519_keypair(enc, private_key_unused);
-
-  // To determine a plausible length for the payload, we estimate the size of a
-  // typical EncodedClientHelloInner without resumption:
-  //
-  //   2+32+1+2   version, random, legacy_session_id, legacy_compression_methods
-  //   2+4*2      cipher_suites (three TLS 1.3 ciphers, GREASE)
-  //   2          extensions prefix
-  //   4          ech_is_inner
-  //   4+1+2*2    supported_versions (TLS 1.3, GREASE)
-  //   4+1+10*2   outer_extensions (key_share, sigalgs, sct, alpn,
-  //              supported_groups, status_request, psk_key_exchange_modes,
-  //              compress_certificate, GREASE x2)
-  //
-  // The server_name extension has an overhead of 9 bytes. For now, arbitrarily
-  // estimate maximum_name_length to be between 32 and 100 bytes.
-  //
-  // TODO(https://crbug.com/boringssl/275): If the padding scheme changes to
-  // also round the entire payload, adjust this to match. See
-  // https://github.com/tlswg/draft-ietf-tls-esni/issues/433
-  const size_t overhead = aead_overhead(aead);
-  const size_t in_len = random_size(128, 196);
-  const size_t extension_len =
-      compute_extension_length(aead, sizeof(enc), in_len);
-  bssl::ScopedCBB cbb;
-  CBB enc_cbb, payload_cbb;
-  uint8_t *payload;
-  if (!CBB_init(cbb.get(), extension_len) ||
-      !CBB_add_u16(cbb.get(), kdf_id) ||
-      !CBB_add_u16(cbb.get(), EVP_HPKE_AEAD_id(aead)) ||
-      !CBB_add_u8(cbb.get(), config_id) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &enc_cbb) ||
-      !CBB_add_bytes(&enc_cbb, enc, sizeof(enc)) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &payload_cbb) ||
-      !CBB_add_space(&payload_cbb, &payload, in_len + overhead) ||
-      !RAND_bytes(payload, in_len + overhead) ||
-      !CBBFinishArray(cbb.get(), &hs->ech_client_bytes)) {
-    return false;
-  }
-  assert(hs->ech_client_bytes.size() == extension_len);
-  return true;
-}
-
-bool ssl_encrypt_client_hello(SSL_HANDSHAKE *hs, Span<const uint8_t> enc) {
-  SSL *const ssl = hs->ssl;
-  if (!hs->selected_ech_config) {
-    return setup_ech_grease(hs);
-  }
-
-  // Construct ClientHelloInner and EncodedClientHelloInner. See
-  // draft-ietf-tls-esni-10, sections 5.1 and 6.1.
-  bssl::ScopedCBB cbb, encoded;
-  CBB body;
-  bool needs_psk_binder;
-  bssl::Array<uint8_t> hello_inner;
-  if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CLIENT_HELLO) ||
-      !CBB_init(encoded.get(), 256) ||
-      !ssl_write_client_hello_without_extensions(hs, &body,
-                                                 ssl_client_hello_inner,
-                                                 /*empty_session_id=*/false) ||
-      !ssl_write_client_hello_without_extensions(hs, encoded.get(),
-                                                 ssl_client_hello_inner,
-                                                 /*empty_session_id=*/true) ||
-      !ssl_add_clienthello_tlsext(hs, &body, encoded.get(), &needs_psk_binder,
-                                  ssl_client_hello_inner, CBB_len(&body),
-                                  /*omit_ech_len=*/0) ||
-      !ssl->method->finish_message(ssl, cbb.get(), &hello_inner)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return false;
-  }
-
-  if (needs_psk_binder) {
-    size_t binder_len;
-    if (!tls13_write_psk_binder(hs, hs->inner_transcript, MakeSpan(hello_inner),
-                                &binder_len)) {
-      return false;
-    }
-    // Also update the EncodedClientHelloInner.
-    if (CBB_len(encoded.get()) < binder_len) {
-      OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-      return false;
-    }
-    OPENSSL_memcpy(const_cast<uint8_t *>(CBB_data(encoded.get())) +
-                       CBB_len(encoded.get()) - binder_len,
-                   hello_inner.data() + hello_inner.size() - binder_len,
-                   binder_len);
-  }
-
-  if (!hs->inner_transcript.Update(hello_inner)) {
-    return false;
-  }
-
-  // Construct ClientHelloOuterAAD. See draft-ietf-tls-esni-10, section 5.2.
-  // TODO(https://crbug.com/boringssl/275): This ends up constructing the
-  // ClientHelloOuter twice. Revisit this in the next draft, which uses a more
-  // forgiving construction.
-  const EVP_HPKE_KDF *kdf = EVP_HPKE_CTX_kdf(hs->ech_hpke_ctx.get());
-  const EVP_HPKE_AEAD *aead = EVP_HPKE_CTX_aead(hs->ech_hpke_ctx.get());
-  const size_t extension_len =
-      compute_extension_length(aead, enc.size(), CBB_len(encoded.get()));
-  bssl::ScopedCBB aad;
-  CBB outer_hello;
-  CBB enc_cbb;
-  if (!CBB_init(aad.get(), 256) ||
-      !CBB_add_u16(aad.get(), EVP_HPKE_KDF_id(kdf)) ||
-      !CBB_add_u16(aad.get(), EVP_HPKE_AEAD_id(aead)) ||
-      !CBB_add_u8(aad.get(), hs->selected_ech_config->config_id) ||
-      !CBB_add_u16_length_prefixed(aad.get(), &enc_cbb) ||
-      !CBB_add_bytes(&enc_cbb, enc.data(), enc.size()) ||
-      !CBB_add_u24_length_prefixed(aad.get(), &outer_hello) ||
-      !ssl_write_client_hello_without_extensions(hs, &outer_hello,
-                                                 ssl_client_hello_outer,
-                                                 /*empty_session_id=*/false) ||
-      !ssl_add_clienthello_tlsext(hs, &outer_hello, /*out_encoded=*/nullptr,
-                                  &needs_psk_binder, ssl_client_hello_outer,
-                                  CBB_len(&outer_hello),
-                                  /*omit_ech_len=*/4 + extension_len) ||
-      !CBB_flush(aad.get())) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return false;
-  }
-  // ClientHelloOuter may not require a PSK binder. Otherwise, we have a
-  // circular dependency.
-  assert(!needs_psk_binder);
-
-  CBB payload_cbb;
-  if (!CBB_init(cbb.get(), extension_len) ||
-      !CBB_add_u16(cbb.get(), EVP_HPKE_KDF_id(kdf)) ||
-      !CBB_add_u16(cbb.get(), EVP_HPKE_AEAD_id(aead)) ||
-      !CBB_add_u8(cbb.get(), hs->selected_ech_config->config_id) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &enc_cbb) ||
-      !CBB_add_bytes(&enc_cbb, enc.data(), enc.size()) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &payload_cbb)) {
-    return false;
-  }
-#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
-  // In fuzzer mode, the server expects a cleartext payload.
-  if (!CBB_add_bytes(&payload_cbb, CBB_data(encoded.get()),
-                     CBB_len(encoded.get()))) {
-    return false;
-  }
-#else
-  uint8_t *payload;
-  size_t payload_len =
-      CBB_len(encoded.get()) + EVP_AEAD_max_overhead(EVP_HPKE_AEAD_aead(aead));
-  if (!CBB_reserve(&payload_cbb, &payload, payload_len) ||
-      !EVP_HPKE_CTX_seal(hs->ech_hpke_ctx.get(), payload, &payload_len,
-                         payload_len, CBB_data(encoded.get()),
-                         CBB_len(encoded.get()), CBB_data(aad.get()),
-                         CBB_len(aad.get())) ||
-      !CBB_did_write(&payload_cbb, payload_len)) {
-    return false;
-  }
-#endif // BORINGSSL_UNSAFE_FUZZER_MODE
-  if (!CBBFinishArray(cbb.get(), &hs->ech_client_bytes)) {
-    return false;
-  }
-
-  // The |aad| calculation relies on |extension_length| being correct.
-  assert(hs->ech_client_bytes.size() == extension_len);
-  return true;
-}
-
-BSSL_NAMESPACE_END
-
-using namespace bssl;
-
-void SSL_set_enable_ech_grease(SSL *ssl, int enable) {
-  if (!ssl->config) {
-    return;
-  }
-  ssl->config->ech_grease_enabled = !!enable;
-}
-
-int SSL_set1_ech_config_list(SSL *ssl, const uint8_t *ech_config_list,
-                             size_t ech_config_list_len) {
-  if (!ssl->config) {
-    return 0;
-  }
-
-  auto span = MakeConstSpan(ech_config_list, ech_config_list_len);
-  if (!ssl_is_valid_ech_config_list(span)) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_ECH_CONFIG_LIST);
-    return 0;
-  }
-  return ssl->config->client_ech_config_list.CopyFrom(span);
-}
-
-void SSL_get0_ech_name_override(const SSL *ssl, const char **out_name,
-                                size_t *out_name_len) {
-  // When ECH is rejected, we use the public name. Note that, if
-  // |SSL_CTX_set_reverify_on_resume| is enabled, we reverify the certificate
-  // before the 0-RTT point. If also offering ECH, we verify as if
-  // ClientHelloInner was accepted and do not override. This works because, at
-  // this point, |ech_status| will be |ssl_ech_none|. See the
-  // ECH-Client-Reject-EarlyDataReject-OverrideNameOnRetry tests in runner.go.
-  const SSL_HANDSHAKE *hs = ssl->s3->hs.get();
-  if (!ssl->server && hs && ssl->s3->ech_status == ssl_ech_rejected) {
-    *out_name = reinterpret_cast<const char *>(
-        hs->selected_ech_config->public_name.data());
-    *out_name_len = hs->selected_ech_config->public_name.size();
-  } else {
-    *out_name = nullptr;
-    *out_name_len = 0;
-  }
-}
-
-void SSL_get0_ech_retry_configs(
-    const SSL *ssl, const uint8_t **out_retry_configs,
-    size_t *out_retry_configs_len) {
-  const SSL_HANDSHAKE *hs = ssl->s3->hs.get();
-  if (!hs || !hs->ech_authenticated_reject) {
-    // It is an error to call this function except in response to
-    // |SSL_R_ECH_REJECTED|. Returning an empty string risks the caller
-    // mistakenly believing the server has disabled ECH. Instead, return a
-    // non-empty ECHConfigList with a syntax error, so the subsequent
-    // |SSL_set1_ech_config_list| call will fail.
-    assert(0);
-    static const uint8_t kPlaceholder[] = {
-        kECHConfigVersion >> 8, kECHConfigVersion & 0xff, 0xff, 0xff, 0xff};
-    *out_retry_configs = kPlaceholder;
-    *out_retry_configs_len = sizeof(kPlaceholder);
-    return;
-  }
-
-  *out_retry_configs = hs->ech_retry_configs.data();
-  *out_retry_configs_len = hs->ech_retry_configs.size();
-}
-
-int SSL_marshal_ech_config(uint8_t **out, size_t *out_len, uint8_t config_id,
-                           const EVP_HPKE_KEY *key, const char *public_name,
-                           size_t max_name_len) {
-  Span<const uint8_t> public_name_u8 = MakeConstSpan(
-      reinterpret_cast<const uint8_t *>(public_name), strlen(public_name));
-  if (!ssl_is_valid_ech_public_name(public_name_u8)) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_ECH_PUBLIC_NAME);
-    return 0;
-  }
-
-  // See draft-ietf-tls-esni-10, section 4.
-  ScopedCBB cbb;
-  CBB contents, child;
-  uint8_t *public_key;
-  size_t public_key_len;
-  if (!CBB_init(cbb.get(), 128) ||  //
-      !CBB_add_u16(cbb.get(), kECHConfigVersion) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &contents) ||
-      !CBB_add_u8(&contents, config_id) ||
-      !CBB_add_u16(&contents, EVP_HPKE_KEM_id(EVP_HPKE_KEY_kem(key))) ||
-      !CBB_add_u16_length_prefixed(&contents, &child) ||
-      !CBB_reserve(&child, &public_key, EVP_HPKE_MAX_PUBLIC_KEY_LENGTH) ||
-      !EVP_HPKE_KEY_public_key(key, public_key, &public_key_len,
-                               EVP_HPKE_MAX_PUBLIC_KEY_LENGTH) ||
-      !CBB_did_write(&child, public_key_len) ||
-      !CBB_add_u16_length_prefixed(&contents, &child) ||
-      // Write a default cipher suite configuration.
-      !CBB_add_u16(&child, EVP_HPKE_HKDF_SHA256) ||
-      !CBB_add_u16(&child, EVP_HPKE_AES_128_GCM) ||
-      !CBB_add_u16(&child, EVP_HPKE_HKDF_SHA256) ||
-      !CBB_add_u16(&child, EVP_HPKE_CHACHA20_POLY1305) ||
-      !CBB_add_u16(&contents, max_name_len) ||
-      !CBB_add_u16_length_prefixed(&contents, &child) ||
-      !CBB_add_bytes(&child, public_name_u8.data(), public_name_u8.size()) ||
-      // TODO(https://crbug.com/boringssl/275): Reserve some GREASE extensions
-      // and include some.
-      !CBB_add_u16(&contents, 0 /* no extensions */) ||
-      !CBB_finish(cbb.get(), out, out_len)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
-    return 0;
-  }
-  return 1;
-}
-
-SSL_ECH_KEYS *SSL_ECH_KEYS_new() { return New<SSL_ECH_KEYS>(); }
-
-void SSL_ECH_KEYS_up_ref(SSL_ECH_KEYS *keys) {
-  CRYPTO_refcount_inc(&keys->references);
-}
-
-void SSL_ECH_KEYS_free(SSL_ECH_KEYS *keys) {
-  if (keys == nullptr ||
-      !CRYPTO_refcount_dec_and_test_zero(&keys->references)) {
-    return;
-  }
-
-  keys->~ssl_ech_keys_st();
-  OPENSSL_free(keys);
-}
-
-int SSL_ECH_KEYS_add(SSL_ECH_KEYS *configs, int is_retry_config,
-                     const uint8_t *ech_config, size_t ech_config_len,
-                     const EVP_HPKE_KEY *key) {
-  UniquePtr<ECHServerConfig> parsed_config = MakeUnique<ECHServerConfig>();
-  if (!parsed_config) {
-    return 0;
-  }
-  if (!parsed_config->Init(MakeConstSpan(ech_config, ech_config_len), key,
-                           !!is_retry_config)) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
-    return 0;
-  }
-  if (!configs->configs.Push(std::move(parsed_config))) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return 0;
-  }
-  return 1;
-}
-
-int SSL_ECH_KEYS_has_duplicate_config_id(const SSL_ECH_KEYS *keys) {
-  bool seen[256] = {false};
-  for (const auto &config : keys->configs) {
-    if (seen[config->ech_config().config_id]) {
-      return 1;
-    }
-    seen[config->ech_config().config_id] = true;
-  }
-  return 0;
-}
-
-int SSL_ECH_KEYS_marshal_retry_configs(const SSL_ECH_KEYS *keys, uint8_t **out,
-                                       size_t *out_len) {
-  ScopedCBB cbb;
-  CBB child;
-  if (!CBB_init(cbb.get(), 128) ||
-      !CBB_add_u16_length_prefixed(cbb.get(), &child)) {
-    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-    return false;
-  }
-  for (const auto &config : keys->configs) {
-    if (config->is_retry_config() &&
-        !CBB_add_bytes(&child, config->ech_config().raw.data(),
-                       config->ech_config().raw.size())) {
-      OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
-      return false;
-    }
-  }
-  return CBB_finish(cbb.get(), out, out_len);
-}
-
-int SSL_CTX_set1_ech_keys(SSL_CTX *ctx, SSL_ECH_KEYS *keys) {
-  bool has_retry_config = false;
-  for (const auto &config : keys->configs) {
-    if (config->is_retry_config()) {
-      has_retry_config = true;
-      break;
-    }
-  }
-  if (!has_retry_config) {
-    OPENSSL_PUT_ERROR(SSL, SSL_R_ECH_SERVER_WOULD_HAVE_NO_RETRY_CONFIGS);
-    return 0;
-  }
-  UniquePtr<SSL_ECH_KEYS> owned_keys = UpRef(keys);
-  MutexWriteLock lock(&ctx->lock);
-  ctx->ech_keys.swap(owned_keys);
-  return 1;
-}
-
-int SSL_ech_accepted(const SSL *ssl) {
-  if (SSL_in_early_data(ssl) && !ssl->server) {
-    // In the client early data state, we report properties as if the server
-    // accepted early data. The server can only accept early data with
-    // ClientHelloInner.
-    return ssl->s3->hs->selected_ech_config != nullptr;
-  }
-
-  return ssl->s3->ech_status == ssl_ech_accepted;
-}