patch: Add option enable record_size_limit (#21)

boring-sys/patches/boringssl-old-ciphers.patch

@@ -4176,7 +4176,7 @@ index 4dd8841b1..23ffcd446 100644
  #if defined(__cplusplus)
  } /* extern C */
 diff --git a/src/include/openssl/ssl.h b/src/include/openssl/ssl.h
-index 53aa9b453..765db2b10 100644
+index 53aa9b453..9f16b7f6c 100644
 --- a/src/include/openssl/ssl.h
 +++ b/src/include/openssl/ssl.h
 @@ -2378,6 +2378,13 @@ OPENSSL_EXPORT int SSL_set1_curves_list(SSL *ssl, const char *curves);
@@ -4193,6 +4193,21 @@ index 53aa9b453..765db2b10 100644
  
  // SSL_get_curve_id returns the ID of the curve used by |ssl|'s most recently
  // completed handshake or 0 if not applicable.
+@@ -4570,6 +4577,14 @@ OPENSSL_EXPORT void SSL_CTX_set_permute_extensions(SSL_CTX *ctx, int enabled);
+ // permute extensions. For now, this is only implemented for the ClientHello.
+ OPENSSL_EXPORT void SSL_set_permute_extensions(SSL *ssl, int enabled);
+ 
++// SSL_set_record_size_limit configures whether sockets on |ssl| should
++// send record size limit extension.
++OPENSSL_EXPORT void SSL_set_record_size_limit(SSL *ssl, uint16_t limit);
++
++// SSL_CTX_set_record_size_limit configures whether sockets on |ctx| should
++// send record size limit extension.
++OPENSSL_EXPORT void SSL_CTX_set_record_size_limit(SSL_CTX *ctx, uint16_t limit);
++
+ // SSL_max_seal_overhead returns the maximum overhead, in bytes, of sealing a
+ // record with |ssl|.
+ OPENSSL_EXPORT size_t SSL_max_seal_overhead(const SSL *ssl);
 diff --git a/src/include/openssl/tls1.h b/src/include/openssl/tls1.h
 index 772fb87a3..4cb6b5667 100644
 --- a/src/include/openssl/tls1.h
@@ -4220,7 +4235,7 @@ index 5c7e881bf..3c0770cf3 100644
    crypto/pkcs8/test/no_encryption.p12
    crypto/pkcs8/test/nss.p12
 diff --git a/src/ssl/extensions.cc b/src/ssl/extensions.cc
-index 5ee280221..feb0606cf 100644
+index 5ee280221..7d25f1023 100644
 --- a/src/ssl/extensions.cc
 +++ b/src/ssl/extensions.cc
 @@ -207,6 +207,10 @@ static bool tls1_check_duplicate_extensions(const CBS *cbs) {
@@ -4263,15 +4278,19 @@ index 5ee280221..feb0606cf 100644
  static bool ext_delegated_credential_parse_clienthello(SSL_HANDSHAKE *hs,
                                                         uint8_t *out_alert,
                                                         CBS *contents) {
-@@ -3094,6 +3117,35 @@ bool ssl_negotiate_alps(SSL_HANDSHAKE *hs, uint8_t *out_alert,
+@@ -3094,6 +3117,39 @@ bool ssl_negotiate_alps(SSL_HANDSHAKE *hs, uint8_t *out_alert,
    return true;
  }
  
 +static bool record_size_limit_add_clienthello(const SSL_HANDSHAKE* hs, CBB* out,
 +    CBB* out_compressible,
 +    ssl_client_hello_type_t type) {
++    if (hs->config->record_size_limit == 0) {
++        return true;
++    }
++
 +    CBB data;
-+    const uint16_t data_ = 0x4001;
++    const uint16_t data_ = hs->config->record_size_limit;
 +    if (!CBB_add_u16(out, TLSEXT_TYPE_record_size_limit) ||
 +        !CBB_add_u16_length_prefixed(out, &data) || !CBB_add_u16(&data, data_) ||
 +        !CBB_flush(out)) {
@@ -4299,7 +4318,7 @@ index 5ee280221..feb0606cf 100644
  // kExtensions contains all the supported extensions.
  static const struct tls_extension kExtensions[] = {
    {
-@@ -3267,6 +3319,13 @@ static const struct tls_extension kExtensions[] = {
+@@ -3267,6 +3323,13 @@ static const struct tls_extension kExtensions[] = {
      ignore_parse_clienthello,
      ext_alps_add_serverhello,
    },
@@ -4390,7 +4409,7 @@ index 971ebd0b1..e70e6c868 100644
    if (hs->min_version < TLS1_3_VERSION && type != ssl_client_hello_inner) {
      bool any_enabled = false;
 diff --git a/src/ssl/internal.h b/src/ssl/internal.h
-index 1e6da2153..045106263 100644
+index 1e6da2153..fcb586101 100644
 --- a/src/ssl/internal.h
 +++ b/src/ssl/internal.h
 @@ -554,8 +554,13 @@ BSSL_NAMESPACE_BEGIN
@@ -4408,6 +4427,26 @@ index 1e6da2153..045106263 100644
  
  // Bits for |algorithm_prf| (handshake digest).
  #define SSL_HANDSHAKE_MAC_DEFAULT 0x1
+@@ -3128,6 +3133,9 @@ struct SSL_CONFIG {
+   // of support for AES hw. The value is only considered if |aes_hw_override| is
+   // true.
+   bool aes_hw_override_value : 1;
++
++  // record_size_limit is whether to send record size limit extension.
++  uint16_t record_size_limit = 0;
+ };
+ 
+ // From RFC 8446, used in determining PSK modes.
+@@ -3748,6 +3756,9 @@ struct ssl_ctx_st {
+   // |aes_hw_override| is true.
+   bool aes_hw_override_value : 1;
+ 
++  // record_size_limit is whether to send record size limit extension.
++  uint16_t record_size_limit = 0;
++
+  private:
+   ~ssl_ctx_st();
+   friend OPENSSL_EXPORT void SSL_CTX_free(SSL_CTX *);
 diff --git a/src/ssl/ssl_cipher.cc b/src/ssl/ssl_cipher.cc
 index ebb075351..17fcaa13c 100644
 --- a/src/ssl/ssl_cipher.cc
@@ -5262,10 +5301,36 @@ index 09a9ad380..a972e8dd1 100644
        return nullptr;
    }
 diff --git a/src/ssl/ssl_lib.cc b/src/ssl/ssl_lib.cc
-index 838761af5..9eb201d37 100644
+index 838761af5..e6304495b 100644
 --- a/src/ssl/ssl_lib.cc
 +++ b/src/ssl/ssl_lib.cc
-@@ -3151,7 +3151,7 @@ namespace fips202205 {
+@@ -684,6 +684,7 @@ SSL *SSL_new(SSL_CTX *ctx) {
+   ssl->config->signed_cert_timestamps_enabled =
+       ctx->signed_cert_timestamps_enabled;
+   ssl->config->ocsp_stapling_enabled = ctx->ocsp_stapling_enabled;
++  ssl->config->record_size_limit = ctx->record_size_limit;
+   ssl->config->handoff = ctx->handoff;
+   ssl->quic_method = ctx->quic_method;
+ 
+@@ -2134,6 +2135,17 @@ void SSL_enable_ocsp_stapling(SSL *ssl) {
+   ssl->config->ocsp_stapling_enabled = true;
+ }
+ 
++void SSL_set_record_size_limit(SSL *ssl, uint16_t limit) {
++  if (!ssl->config) {
++    return;
++  }
++  ssl->config->record_size_limit = limit;
++}
++
++void SSL_CTX_set_record_size_limit(SSL_CTX *ctx, uint16_t limit) {
++  ctx->record_size_limit = limit;
++}
++
+ void SSL_get0_signed_cert_timestamp_list(const SSL *ssl, const uint8_t **out,
+                                          size_t *out_len) {
+   SSL_SESSION *session = SSL_get_session(ssl);
+@@ -3151,7 +3163,7 @@ namespace fips202205 {
  // Section 3.3.1
  // "The server shall be configured to only use cipher suites that are
  // composed entirely of NIST approved algorithms"

boring/src/ssl/mod.rs

@@ -1865,6 +1865,12 @@ impl SslContextBuilder {
         unsafe { ffi::SSL_CTX_set_grease_enabled(self.as_ptr(), enabled as _) }
     }
 
+    /// Sets whether the context should enable record size limit.
+    #[corresponds(SSL_CTX_set_record_size_limit)]
+    pub fn set_record_size_limit(&mut self, limit: u16) {
+        unsafe { ffi::SSL_CTX_set_record_size_limit(self.as_ptr(), limit as _) }
+    }
+
     /// Configures whether ClientHello extensions should be permuted.
     ///
     /// Note: This is gated to non-fips because the fips feature builds with a separate