| /* 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 <stdio.h> |
| |
| #include <vector> |
| |
| #include <openssl/bytestring.h> |
| #include <openssl/hpke.h> |
| #include <openssl/span.h> |
| #include <openssl/ssl.h> |
| |
| #include "internal.h" |
| |
| |
| static const struct argument kArguments[] = { |
| { |
| "-out-ech-config-list", |
| kRequiredArgument, |
| "The path where the ECHConfigList should be written.", |
| }, |
| { |
| "-out-ech-config", |
| kRequiredArgument, |
| "The path where the ECHConfig should be written.", |
| }, |
| { |
| "-out-private-key", |
| kRequiredArgument, |
| "The path where the private key should be written.", |
| }, |
| { |
| "-public-name", |
| kRequiredArgument, |
| "The public name for the new ECHConfig.", |
| }, |
| { |
| "-config-id", |
| kRequiredArgument, |
| "The config ID for the new ECHConfig, from 0 to 255. Config IDs may be " |
| "reused, but should be unique among active configs on a server for " |
| "performance.", |
| }, |
| { |
| "-max-name-length", |
| kOptionalArgument, |
| "The length of the longest name in the anonymity set, to guide client " |
| "padding.", |
| }, |
| { |
| "", |
| kOptionalArgument, |
| "", |
| }, |
| }; |
| |
| bool GenerateECH(const std::vector<std::string> &args) { |
| std::map<std::string, std::string> args_map; |
| if (!ParseKeyValueArguments(&args_map, args, kArguments)) { |
| PrintUsage(kArguments); |
| return false; |
| } |
| |
| unsigned config_id; |
| if (!GetUnsigned(&config_id, "-config-id", 0, args_map) || |
| config_id > std::numeric_limits<uint8_t>::max()) { |
| fprintf(stderr, "Error parsing -config-id argument\n"); |
| return false; |
| } |
| |
| unsigned max_name_len = 0; |
| if (args_map.count("-max-name-length") != 0 && |
| !GetUnsigned(&max_name_len, "-max-name-length", 0, args_map)) { |
| fprintf(stderr, "Error parsing -max-name-length argument\n"); |
| return false; |
| } |
| |
| bssl::ScopedEVP_HPKE_KEY key; |
| uint8_t public_key[EVP_HPKE_MAX_PUBLIC_KEY_LENGTH]; |
| uint8_t private_key[EVP_HPKE_MAX_PRIVATE_KEY_LENGTH]; |
| size_t public_key_len, private_key_len; |
| if (!EVP_HPKE_KEY_generate(key.get(), EVP_hpke_x25519_hkdf_sha256()) || |
| !EVP_HPKE_KEY_public_key(key.get(), public_key, &public_key_len, |
| sizeof(public_key)) || |
| !EVP_HPKE_KEY_private_key(key.get(), private_key, &private_key_len, |
| sizeof(private_key))) { |
| fprintf(stderr, "Failed to generate the HPKE keypair\n"); |
| return false; |
| } |
| |
| uint8_t *ech_config; |
| size_t ech_config_len; |
| if (!SSL_marshal_ech_config( |
| &ech_config, &ech_config_len, static_cast<uint8_t>(config_id), |
| key.get(), args_map["-public-name"].c_str(), size_t{max_name_len})) { |
| fprintf(stderr, "Failed to serialize the ECHConfigList\n"); |
| return false; |
| } |
| bssl::UniquePtr<uint8_t> free_ech_config(ech_config); |
| |
| bssl::ScopedCBB cbb; |
| CBB body; |
| if (!CBB_init(cbb.get(), ech_config_len + sizeof(uint16_t)) || |
| !CBB_add_u16_length_prefixed(cbb.get(), &body) || |
| !CBB_add_bytes(&body, ech_config, ech_config_len) || |
| !CBB_flush(cbb.get())) { |
| fprintf(stderr, "Failed to serialize the ECHConfigList\n"); |
| return false; |
| } |
| if (!WriteToFile( |
| args_map["-out-ech-config-list"], |
| bssl::MakeConstSpan(CBB_data(cbb.get()), CBB_len(cbb.get()))) || |
| !WriteToFile(args_map["-out-ech-config"], |
| bssl::MakeConstSpan(ech_config, ech_config_len)) || |
| !WriteToFile(args_map["-out-private-key"], |
| bssl::MakeConstSpan(private_key, private_key_len))) { |
| fprintf(stderr, "Failed to write ECHConfig or private key to file\n"); |
| return false; |
| } |
| return true; |
| } |