Mercurial > hg > nginx
view src/event/ngx_event_quic_protection.c @ 8357:05b8dd5d9f7e quic
Retired the ngx_quic_parse_int_multi() function.
It used variable-length arguments what is not really necessary.
author | Vladimir Homutov <vl@nginx.com> |
---|---|
date | Thu, 23 Apr 2020 12:10:56 +0300 |
parents | aba84d9ab256 |
children | 2f900ae486bc |
line wrap: on
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_QUIC_IV_LEN 12 #define NGX_AES_128_GCM_SHA256 0x1301 #define NGX_AES_256_GCM_SHA384 0x1302 #define NGX_CHACHA20_POLY1305_SHA256 0x1303 #ifdef OPENSSL_IS_BORINGSSL #define ngx_quic_cipher_t EVP_AEAD #else #define ngx_quic_cipher_t EVP_CIPHER #endif typedef struct { const ngx_quic_cipher_t *c; const EVP_CIPHER *hp; const EVP_MD *d; } ngx_quic_ciphers_t; static ngx_int_t ngx_hkdf_expand(u_char *out_key, size_t out_len, const EVP_MD *digest, const u_char *prk, size_t prk_len, const u_char *info, size_t info_len); static ngx_int_t ngx_hkdf_extract(u_char *out_key, size_t *out_len, const EVP_MD *digest, const u_char *secret, size_t secret_len, const u_char *salt, size_t salt_len); static uint64_t ngx_quic_parse_pn(u_char **pos, ngx_int_t len, u_char *mask, uint64_t *largest_pn); static void ngx_quic_compute_nonce(u_char *nonce, size_t len, uint64_t pn); static ngx_int_t ngx_quic_ciphers(ngx_ssl_conn_t *ssl_conn, ngx_quic_ciphers_t *ciphers, enum ssl_encryption_level_t level); static ngx_int_t ngx_quic_tls_open(const ngx_quic_cipher_t *cipher, ngx_quic_secret_t *s, ngx_str_t *out, u_char *nonce, ngx_str_t *in, ngx_str_t *ad, ngx_log_t *log); static ngx_int_t ngx_quic_tls_seal(const ngx_quic_cipher_t *cipher, ngx_quic_secret_t *s, ngx_str_t *out, u_char *nonce, ngx_str_t *in, ngx_str_t *ad, ngx_log_t *log); static ngx_int_t ngx_quic_tls_hp(ngx_log_t *log, const EVP_CIPHER *cipher, ngx_quic_secret_t *s, u_char *out, u_char *in); static ngx_int_t ngx_quic_hkdf_expand(ngx_pool_t *pool, const EVP_MD *digest, ngx_str_t *out, ngx_str_t *label, const uint8_t *prk, size_t prk_len); static ssize_t ngx_quic_create_long_packet(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, ngx_str_t *res); static ssize_t ngx_quic_create_short_packet(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, ngx_str_t *res); static ngx_int_t ngx_quic_ciphers(ngx_ssl_conn_t *ssl_conn, ngx_quic_ciphers_t *ciphers, enum ssl_encryption_level_t level) { ngx_int_t id, len; const SSL_CIPHER *cipher; if (level == ssl_encryption_initial) { id = NGX_AES_128_GCM_SHA256; } else { cipher = SSL_get_current_cipher(ssl_conn); if (cipher == NULL) { return NGX_ERROR; } id = SSL_CIPHER_get_id(cipher) & 0xffff; } switch (id) { case NGX_AES_128_GCM_SHA256: #ifdef OPENSSL_IS_BORINGSSL ciphers->c = EVP_aead_aes_128_gcm(); #else ciphers->c = EVP_aes_128_gcm(); #endif ciphers->hp = EVP_aes_128_ctr(); ciphers->d = EVP_sha256(); len = 16; break; case NGX_AES_256_GCM_SHA384: #ifdef OPENSSL_IS_BORINGSSL ciphers->c = EVP_aead_aes_256_gcm(); #else ciphers->c = EVP_aes_256_gcm(); #endif ciphers->hp = EVP_aes_256_ctr(); ciphers->d = EVP_sha384(); len = 32; break; case NGX_CHACHA20_POLY1305_SHA256: #ifdef OPENSSL_IS_BORINGSSL ciphers->c = EVP_aead_chacha20_poly1305(); #else ciphers->c = EVP_chacha20_poly1305(); #endif #ifdef OPENSSL_IS_BORINGSSL ciphers->hp = (const EVP_CIPHER *) EVP_aead_chacha20_poly1305(); #else ciphers->hp = EVP_chacha20(); #endif ciphers->d = EVP_sha256(); len = 32; break; default: return NGX_ERROR; } return len; } ngx_int_t ngx_quic_set_initial_secret(ngx_pool_t *pool, ngx_quic_secret_t *client, ngx_quic_secret_t *server, ngx_str_t *secret) { size_t is_len; uint8_t is[SHA256_DIGEST_LENGTH]; ngx_uint_t i; const EVP_MD *digest; const EVP_CIPHER *cipher; static const uint8_t salt[20] = "\xc3\xee\xf7\x12\xc7\x2e\xbb\x5a\x11\xa7" "\xd2\x43\x2b\xb4\x63\x65\xbe\xf9\xf5\x02"; /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.3 */ cipher = EVP_aes_128_gcm(); digest = EVP_sha256(); if (ngx_hkdf_extract(is, &is_len, digest, secret->data, secret->len, salt, sizeof(salt)) != NGX_OK) { return NGX_ERROR; } ngx_str_t iss = { .data = is, .len = is_len }; ngx_quic_hexdump0(pool->log, "salt", salt, sizeof(salt)); ngx_quic_hexdump0(pool->log, "initial secret", is, is_len); /* draft-ietf-quic-tls-23#section-5.2 */ client->secret.len = SHA256_DIGEST_LENGTH; server->secret.len = SHA256_DIGEST_LENGTH; client->key.len = EVP_CIPHER_key_length(cipher); server->key.len = EVP_CIPHER_key_length(cipher); client->hp.len = EVP_CIPHER_key_length(cipher); server->hp.len = EVP_CIPHER_key_length(cipher); client->iv.len = EVP_CIPHER_iv_length(cipher); server->iv.len = EVP_CIPHER_iv_length(cipher); struct { ngx_str_t label; ngx_str_t *key; ngx_str_t *prk; } seq[] = { /* draft-ietf-quic-tls-23#section-5.2 */ { ngx_string("tls13 client in"), &client->secret, &iss }, { ngx_string("tls13 quic key"), &client->key, &client->secret, }, { ngx_string("tls13 quic iv"), &client->iv, &client->secret, }, { /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */ ngx_string("tls13 quic hp"), &client->hp, &client->secret, }, { ngx_string("tls13 server in"), &server->secret, &iss }, { /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.3 */ ngx_string("tls13 quic key"), &server->key, &server->secret, }, { ngx_string("tls13 quic iv"), &server->iv, &server->secret, }, { /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */ ngx_string("tls13 quic hp"), &server->hp, &server->secret, }, }; for (i = 0; i < (sizeof(seq) / sizeof(seq[0])); i++) { if (ngx_quic_hkdf_expand(pool, digest, seq[i].key, &seq[i].label, seq[i].prk->data, seq[i].prk->len) != NGX_OK) { return NGX_ERROR; } } return NGX_OK; } static ngx_int_t ngx_quic_hkdf_expand(ngx_pool_t *pool, const EVP_MD *digest, ngx_str_t *out, ngx_str_t *label, const uint8_t *prk, size_t prk_len) { size_t info_len; uint8_t *p; uint8_t info[20]; if (out->data == NULL) { out->data = ngx_pnalloc(pool, out->len); if (out->data == NULL) { return NGX_ERROR; } } info_len = 2 + 1 + label->len + 1; info[0] = 0; info[1] = out->len; info[2] = label->len; p = ngx_cpymem(&info[3], label->data, label->len); *p = '\0'; if (ngx_hkdf_expand(out->data, out->len, digest, prk, prk_len, info, info_len) != NGX_OK) { ngx_ssl_error(NGX_LOG_INFO, pool->log, 0, "ngx_hkdf_expand(%V) failed", label); return NGX_ERROR; } ngx_quic_hexdump(pool->log, "%V info", info, info_len, label); ngx_quic_hexdump(pool->log, "%V key", out->data, out->len, label); return NGX_OK; } static ngx_int_t ngx_hkdf_expand(u_char *out_key, size_t out_len, const EVP_MD *digest, const uint8_t *prk, size_t prk_len, const u_char *info, size_t info_len) { #ifdef OPENSSL_IS_BORINGSSL if (HKDF_expand(out_key, out_len, digest, prk, prk_len, info, info_len) == 0) { return NGX_ERROR; } #else EVP_PKEY_CTX *pctx; pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL); if (EVP_PKEY_derive_init(pctx) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXPAND_ONLY) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_set_hkdf_md(pctx, digest) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_set1_hkdf_key(pctx, prk, prk_len) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_add1_hkdf_info(pctx, info, info_len) <= 0) { return NGX_ERROR; } if (EVP_PKEY_derive(pctx, out_key, &out_len) <= 0) { return NGX_ERROR; } #endif return NGX_OK; } static ngx_int_t ngx_hkdf_extract(u_char *out_key, size_t *out_len, const EVP_MD *digest, const u_char *secret, size_t secret_len, const u_char *salt, size_t salt_len) { #ifdef OPENSSL_IS_BORINGSSL if (HKDF_extract(out_key, out_len, digest, secret, secret_len, salt, salt_len) == 0) { return NGX_ERROR; } #else EVP_PKEY_CTX *pctx; pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL); if (EVP_PKEY_derive_init(pctx) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_set_hkdf_md(pctx, digest) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_set1_hkdf_key(pctx, secret, secret_len) <= 0) { return NGX_ERROR; } if (EVP_PKEY_CTX_set1_hkdf_salt(pctx, salt, salt_len) <= 0) { return NGX_ERROR; } if (EVP_PKEY_derive(pctx, out_key, out_len) <= 0) { return NGX_ERROR; } #endif return NGX_OK; } static ngx_int_t ngx_quic_tls_open(const ngx_quic_cipher_t *cipher, ngx_quic_secret_t *s, ngx_str_t *out, u_char *nonce, ngx_str_t *in, ngx_str_t *ad, ngx_log_t *log) { #ifdef OPENSSL_IS_BORINGSSL EVP_AEAD_CTX *ctx; ctx = EVP_AEAD_CTX_new(cipher, s->key.data, s->key.len, EVP_AEAD_DEFAULT_TAG_LENGTH); if (ctx == NULL) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_AEAD_CTX_new() failed"); return NGX_ERROR; } if (EVP_AEAD_CTX_open(ctx, out->data, &out->len, out->len, nonce, s->iv.len, in->data, in->len, ad->data, ad->len) != 1) { EVP_AEAD_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_AEAD_CTX_open() failed"); return NGX_ERROR; } EVP_AEAD_CTX_free(ctx); #else int len; u_char *tag; EVP_CIPHER_CTX *ctx; ctx = EVP_CIPHER_CTX_new(); if (ctx == NULL) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_new() failed"); return NGX_ERROR; } if (EVP_DecryptInit_ex(ctx, cipher, NULL, NULL, NULL) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_DecryptInit_ex() failed"); return NGX_ERROR; } if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, s->iv.len, NULL) == 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_ctrl(EVP_CTRL_GCM_SET_IVLEN) failed"); return NGX_ERROR; } if (EVP_DecryptInit_ex(ctx, NULL, NULL, s->key.data, nonce) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_DecryptInit_ex() failed"); return NGX_ERROR; } if (EVP_DecryptUpdate(ctx, NULL, &len, ad->data, ad->len) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_DecryptUpdate() failed"); return NGX_ERROR; } if (EVP_DecryptUpdate(ctx, out->data, &len, in->data, in->len - EVP_GCM_TLS_TAG_LEN) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_DecryptUpdate() failed"); return NGX_ERROR; } out->len = len; tag = in->data + in->len - EVP_GCM_TLS_TAG_LEN; if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, EVP_GCM_TLS_TAG_LEN, tag) == 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_ctrl(EVP_CTRL_GCM_SET_TAG) failed"); return NGX_ERROR; } if (EVP_DecryptFinal_ex(ctx, out->data + len, &len) <= 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_DecryptFinal_ex failed"); return NGX_ERROR; } out->len += len; EVP_CIPHER_CTX_free(ctx); #endif return NGX_OK; } static ngx_int_t ngx_quic_tls_seal(const ngx_quic_cipher_t *cipher, ngx_quic_secret_t *s, ngx_str_t *out, u_char *nonce, ngx_str_t *in, ngx_str_t *ad, ngx_log_t *log) { #ifdef OPENSSL_IS_BORINGSSL EVP_AEAD_CTX *ctx; ctx = EVP_AEAD_CTX_new(cipher, s->key.data, s->key.len, EVP_AEAD_DEFAULT_TAG_LENGTH); if (ctx == NULL) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_AEAD_CTX_new() failed"); return NGX_ERROR; } if (EVP_AEAD_CTX_seal(ctx, out->data, &out->len, out->len, nonce, s->iv.len, in->data, in->len, ad->data, ad->len) != 1) { EVP_AEAD_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_AEAD_CTX_seal() failed"); return NGX_ERROR; } EVP_AEAD_CTX_free(ctx); #else int len; EVP_CIPHER_CTX *ctx; ctx = EVP_CIPHER_CTX_new(); if (ctx == NULL) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_new() failed"); return NGX_ERROR; } if (EVP_EncryptInit_ex(ctx, cipher, NULL, NULL, NULL) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptInit_ex() failed"); return NGX_ERROR; } if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, s->iv.len, NULL) == 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_ctrl(EVP_CTRL_GCM_SET_IVLEN) failed"); return NGX_ERROR; } if (EVP_EncryptInit_ex(ctx, NULL, NULL, s->key.data, nonce) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptInit_ex() failed"); return NGX_ERROR; } if (EVP_EncryptUpdate(ctx, NULL, &len, ad->data, ad->len) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptUpdate() failed"); return NGX_ERROR; } if (EVP_EncryptUpdate(ctx, out->data, &len, in->data, in->len) != 1) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptUpdate() failed"); return NGX_ERROR; } out->len = len; if (EVP_EncryptFinal_ex(ctx, out->data + out->len, &len) <= 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptFinal_ex failed"); return NGX_ERROR; } out->len += len; if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, EVP_GCM_TLS_TAG_LEN, out->data + in->len) == 0) { EVP_CIPHER_CTX_free(ctx); ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_CIPHER_CTX_ctrl(EVP_CTRL_GCM_GET_TAG) failed"); return NGX_ERROR; } EVP_CIPHER_CTX_free(ctx); out->len += EVP_GCM_TLS_TAG_LEN; #endif return NGX_OK; } static ngx_int_t ngx_quic_tls_hp(ngx_log_t *log, const EVP_CIPHER *cipher, ngx_quic_secret_t *s, u_char *out, u_char *in) { int outlen; EVP_CIPHER_CTX *ctx; u_char zero[5] = {0}; #ifdef OPENSSL_IS_BORINGSSL uint32_t counter; ngx_memcpy(&counter, in, sizeof(uint32_t)); if (cipher == (const EVP_CIPHER *) EVP_aead_chacha20_poly1305()) { CRYPTO_chacha_20(out, zero, 5, s->hp.data, &in[4], counter); return NGX_OK; } #endif ctx = EVP_CIPHER_CTX_new(); if (ctx == NULL) { return NGX_ERROR; } if (EVP_EncryptInit_ex(ctx, cipher, NULL, s->hp.data, in) != 1) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptInit_ex() failed"); goto failed; } if (!EVP_EncryptUpdate(ctx, out, &outlen, zero, 5)) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptUpdate() failed"); goto failed; } if (!EVP_EncryptFinal_ex(ctx, out + 5, &outlen)) { ngx_ssl_error(NGX_LOG_INFO, log, 0, "EVP_EncryptFinal_Ex() failed"); goto failed; } EVP_CIPHER_CTX_free(ctx); return NGX_OK; failed: EVP_CIPHER_CTX_free(ctx); return NGX_ERROR; } int ngx_quic_set_encryption_secret(ngx_pool_t *pool, ngx_ssl_conn_t *ssl_conn, enum ssl_encryption_level_t level, const uint8_t *secret, size_t secret_len, ngx_quic_secret_t *peer_secret) { ngx_int_t key_len; ngx_uint_t i; ngx_quic_ciphers_t ciphers; key_len = ngx_quic_ciphers(ssl_conn, &ciphers, level); if (key_len == NGX_ERROR) { ngx_ssl_error(NGX_LOG_INFO, pool->log, 0, "unexpected cipher"); return 0; } if (level == ssl_encryption_initial) { return 0; } peer_secret->secret.data = ngx_pnalloc(pool, secret_len); if (peer_secret->secret.data == NULL) { return NGX_ERROR; } peer_secret->secret.len = secret_len; ngx_memcpy(peer_secret->secret.data, secret, secret_len); peer_secret->key.len = key_len; peer_secret->iv.len = NGX_QUIC_IV_LEN; peer_secret->hp.len = key_len; struct { ngx_str_t label; ngx_str_t *key; const uint8_t *secret; } seq[] = { { ngx_string("tls13 quic key"), &peer_secret->key, secret }, { ngx_string("tls13 quic iv"), &peer_secret->iv, secret }, { ngx_string("tls13 quic hp"), &peer_secret->hp, secret }, }; for (i = 0; i < (sizeof(seq) / sizeof(seq[0])); i++) { if (ngx_quic_hkdf_expand(pool, ciphers.d, seq[i].key, &seq[i].label, seq[i].secret, secret_len) != NGX_OK) { return 0; } } return 1; } ngx_int_t ngx_quic_key_update(ngx_connection_t *c, ngx_quic_secrets_t *current, ngx_quic_secrets_t *next) { ngx_uint_t i; ngx_quic_ciphers_t ciphers; ngx_log_debug(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic key update"); if (ngx_quic_ciphers(c->ssl->connection, &ciphers, ssl_encryption_application) == NGX_ERROR) { return NGX_ERROR; } next->client.secret.len = current->client.secret.len; next->client.key.len = current->client.key.len; next->client.iv.len = current->client.iv.len; next->client.hp = current->client.hp; next->server.secret.len = current->server.secret.len; next->server.key.len = current->server.key.len; next->server.iv.len = current->server.iv.len; next->server.hp = current->server.hp; struct { ngx_str_t label; ngx_str_t *key; ngx_str_t *secret; } seq[] = { { ngx_string("tls13 quic ku"), &next->client.secret, ¤t->client.secret, }, { ngx_string("tls13 quic key"), &next->client.key, &next->client.secret, }, { ngx_string("tls13 quic iv"), &next->client.iv, &next->client.secret, }, { ngx_string("tls13 quic ku"), &next->server.secret, ¤t->server.secret, }, { ngx_string("tls13 quic key"), &next->server.key, &next->server.secret, }, { ngx_string("tls13 quic iv"), &next->server.iv, &next->server.secret, }, }; for (i = 0; i < (sizeof(seq) / sizeof(seq[0])); i++) { if (ngx_quic_hkdf_expand(c->pool, ciphers.d, seq[i].key, &seq[i].label, seq[i].secret->data, seq[i].secret->len) != NGX_OK) { return NGX_ERROR; } } return NGX_OK; } static ssize_t ngx_quic_create_long_packet(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, ngx_str_t *res) { u_char *pnp, *sample; ngx_str_t ad, out; ngx_uint_t i; ngx_quic_ciphers_t ciphers; u_char nonce[12], mask[16]; out.len = pkt->payload.len + EVP_GCM_TLS_TAG_LEN; ad.data = res->data; ad.len = ngx_quic_create_long_header(pkt, ad.data, out.len, &pnp); out.data = res->data + ad.len; ngx_quic_hexdump0(pkt->log, "ad", ad.data, ad.len); if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { return NGX_ERROR; } ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pkt->log, 0, "ngx_quic_create_long_packet: number %L, encoded %d:0x%xD", pkt->number, (int) pkt->num_len, pkt->trunc); ngx_memcpy(nonce, pkt->secret->iv.data, pkt->secret->iv.len); ngx_quic_compute_nonce(nonce, sizeof(nonce), pkt->number); ngx_quic_hexdump0(pkt->log, "server_iv", pkt->secret->iv.data, 12); ngx_quic_hexdump0(pkt->log, "nonce", nonce, 12); if (ngx_quic_tls_seal(ciphers.c, pkt->secret, &out, nonce, &pkt->payload, &ad, pkt->log) != NGX_OK) { return NGX_ERROR; } sample = &out.data[4 - pkt->num_len]; if (ngx_quic_tls_hp(pkt->log, ciphers.hp, pkt->secret, mask, sample) != NGX_OK) { return NGX_ERROR; } ngx_quic_hexdump0(pkt->log, "sample", sample, 16); ngx_quic_hexdump0(pkt->log, "mask", mask, 5); /* quic-tls: 5.4.1. Header Protection Application */ ad.data[0] ^= mask[0] & 0x0f; for (i = 0; i < pkt->num_len; i++) { pnp[i] ^= mask[i + 1]; } res->len = ad.len + out.len; return NGX_OK; } static ssize_t ngx_quic_create_short_packet(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, ngx_str_t *res) { u_char *pnp, *sample; ngx_str_t ad, out; ngx_uint_t i; ngx_quic_ciphers_t ciphers; u_char nonce[12], mask[16]; out.len = pkt->payload.len + EVP_GCM_TLS_TAG_LEN; ad.data = res->data; ad.len = ngx_quic_create_short_header(pkt, ad.data, out.len, &pnp); out.data = res->data + ad.len; ngx_quic_hexdump0(pkt->log, "ad", ad.data, ad.len); if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { return NGX_ERROR; } ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pkt->log, 0, "ngx_quic_create_short_packet: number %L, encoded %d:0x%xD", pkt->number, (int) pkt->num_len, pkt->trunc); ngx_memcpy(nonce, pkt->secret->iv.data, pkt->secret->iv.len); ngx_quic_compute_nonce(nonce, sizeof(nonce), pkt->number); ngx_quic_hexdump0(pkt->log, "server_iv", pkt->secret->iv.data, 12); ngx_quic_hexdump0(pkt->log, "nonce", nonce, 12); if (ngx_quic_tls_seal(ciphers.c, pkt->secret, &out, nonce, &pkt->payload, &ad, pkt->log) != NGX_OK) { return NGX_ERROR; } sample = &out.data[4 - pkt->num_len]; if (ngx_quic_tls_hp(pkt->log, ciphers.hp, pkt->secret, mask, sample) != NGX_OK) { return NGX_ERROR; } ngx_quic_hexdump0(pkt->log, "sample", sample, 16); ngx_quic_hexdump0(pkt->log, "mask", mask, 5); /* quic-tls: 5.4.1. Header Protection Application */ ad.data[0] ^= mask[0] & 0x1f; for (i = 0; i < pkt->num_len; i++) { pnp[i] ^= mask[i + 1]; } res->len = ad.len + out.len; return NGX_OK; } static uint64_t ngx_quic_parse_pn(u_char **pos, ngx_int_t len, u_char *mask, uint64_t *largest_pn) { u_char *p; uint64_t truncated_pn, expected_pn, candidate_pn; uint64_t pn_nbits, pn_win, pn_hwin, pn_mask; pn_nbits = ngx_min(len * 8, 62); p = *pos; truncated_pn = *p++ ^ *mask++; while (--len) { truncated_pn = (truncated_pn << 8) + (*p++ ^ *mask++); } *pos = p; expected_pn = *largest_pn + 1; pn_win = 1 << pn_nbits; pn_hwin = pn_win / 2; pn_mask = pn_win - 1; candidate_pn = (expected_pn & ~pn_mask) | truncated_pn; if ((int64_t) candidate_pn <= (int64_t) (expected_pn - pn_hwin) && candidate_pn < (1ULL << 62) - pn_win) { candidate_pn += pn_win; } else if (candidate_pn > expected_pn + pn_hwin && candidate_pn >= pn_win) { candidate_pn -= pn_win; } *largest_pn = ngx_max((int64_t) *largest_pn, (int64_t) candidate_pn); return candidate_pn; } static void ngx_quic_compute_nonce(u_char *nonce, size_t len, uint64_t pn) { nonce[len - 4] ^= (pn & 0xff000000) >> 24; nonce[len - 3] ^= (pn & 0x00ff0000) >> 16; nonce[len - 2] ^= (pn & 0x0000ff00) >> 8; nonce[len - 1] ^= (pn & 0x000000ff); } ssize_t ngx_quic_encrypt(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, ngx_str_t *res) { if (pkt->level == ssl_encryption_application) { return ngx_quic_create_short_packet(pkt, ssl_conn, res); } return ngx_quic_create_long_packet(pkt, ssl_conn, res); } ngx_int_t ngx_quic_decrypt(ngx_quic_header_t *pkt, ngx_ssl_conn_t *ssl_conn, uint64_t *largest_pn) { u_char clearflags, *p, *sample; uint64_t pn; ngx_int_t pnl, rc, key_phase; ngx_str_t in, ad; ngx_quic_secret_t *secret; ngx_quic_ciphers_t ciphers; uint8_t mask[16], nonce[12]; if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { return NGX_ERROR; } secret = pkt->secret; p = pkt->raw->pos; /* draft-ietf-quic-tls-23#section-5.4.2: * the Packet Number field is assumed to be 4 bytes long * draft-ietf-quic-tls-23#section-5.4.[34]: * AES-Based and ChaCha20-Based header protections sample 16 bytes */ sample = p + 4; ngx_quic_hexdump0(pkt->log, "sample", sample, 16); /* header protection */ if (ngx_quic_tls_hp(pkt->log, ciphers.hp, secret, mask, sample) != NGX_OK) { return NGX_ERROR; } if (ngx_quic_long_pkt(pkt->flags)) { clearflags = pkt->flags ^ (mask[0] & 0x0f); } else { clearflags = pkt->flags ^ (mask[0] & 0x1f); key_phase = (clearflags & NGX_QUIC_PKT_KPHASE) != 0; if (key_phase != pkt->key_phase) { secret = pkt->next; pkt->key_update = 1; } } pnl = (clearflags & 0x03) + 1; pn = ngx_quic_parse_pn(&p, pnl, &mask[1], largest_pn); pkt->pn = pn; ngx_quic_hexdump0(pkt->log, "mask", mask, 5); ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pkt->log, 0, "quic clear flags: %xi", clearflags); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, pkt->log, 0, "quic packet number: %uL, len: %xi", pn, pnl); /* packet protection */ in.data = p; if (ngx_quic_long_pkt(pkt->flags)) { in.len = pkt->len - pnl; } else { in.len = pkt->data + pkt->len - p; } ad.len = p - pkt->data; ad.data = pkt->plaintext; ngx_memcpy(ad.data, pkt->data, ad.len); ad.data[0] = clearflags; do { ad.data[ad.len - pnl] = pn >> (8 * (pnl - 1)) % 256; } while (--pnl); ngx_memcpy(nonce, secret->iv.data, secret->iv.len); ngx_quic_compute_nonce(nonce, sizeof(nonce), pn); ngx_quic_hexdump0(pkt->log, "nonce", nonce, 12); ngx_quic_hexdump0(pkt->log, "ad", ad.data, ad.len); pkt->payload.len = in.len - EVP_GCM_TLS_TAG_LEN; if (NGX_QUIC_DEFAULT_MAX_PACKET_SIZE - ad.len < pkt->payload.len) { return NGX_ERROR; } pkt->payload.data = pkt->plaintext + ad.len; rc = ngx_quic_tls_open(ciphers.c, secret, &pkt->payload, nonce, &in, &ad, pkt->log); ngx_quic_hexdump0(pkt->log, "packet payload", pkt->payload.data, pkt->payload.len); return rc; }