diff options
Diffstat (limited to 'src/event/ngx_event_quic_protection.c')
| -rw-r--r-- | src/event/ngx_event_quic_protection.c | 987 |
1 files changed, 987 insertions, 0 deletions
diff --git a/src/event/ngx_event_quic_protection.c b/src/event/ngx_event_quic_protection.c new file mode 100644 index 000000000..544adaace --- /dev/null +++ b/src/event/ngx_event_quic_protection.c @@ -0,0 +1,987 @@ + +/* + * 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); +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(ngx_pool_t *pool, 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); +static ngx_int_t ngx_quic_tls_seal(ngx_pool_t *pool, + 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); +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 ngx_int_t ngx_quic_create_long_packet(ngx_pool_t *pool, + ngx_ssl_conn_t *ssl_conn, ngx_quic_header_t *pkt, ngx_str_t *in, + ngx_str_t *res); + +static ngx_int_t ngx_quic_create_short_packet(ngx_pool_t *pool, + ngx_ssl_conn_t *ssl_conn, ngx_quic_header_t *pkt, ngx_str_t *in, + 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; + + if (level == ssl_encryption_initial) { + id = NGX_AES_128_GCM_SHA256; + + } else { + id = SSL_CIPHER_get_id(SSL_get_current_cipher(ssl_conn)) & 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_secrets_t *qsec, + 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 */ + qsec->client.in.secret.len = SHA256_DIGEST_LENGTH; + qsec->server.in.secret.len = SHA256_DIGEST_LENGTH; + + qsec->client.in.key.len = EVP_CIPHER_key_length(cipher); + qsec->server.in.key.len = EVP_CIPHER_key_length(cipher); + + qsec->client.in.hp.len = EVP_CIPHER_key_length(cipher); + qsec->server.in.hp.len = EVP_CIPHER_key_length(cipher); + + qsec->client.in.iv.len = EVP_CIPHER_iv_length(cipher); + qsec->server.in.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"), &qsec->client.in.secret, &iss }, + { + ngx_string("tls13 quic key"), + &qsec->client.in.key, + &qsec->client.in.secret, + }, + { + ngx_string("tls13 quic iv"), + &qsec->client.in.iv, + &qsec->client.in.secret, + }, + { + /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */ + ngx_string("tls13 quic hp"), + &qsec->client.in.hp, + &qsec->client.in.secret, + }, + { ngx_string("tls13 server in"), &qsec->server.in.secret, &iss }, + { + /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.3 */ + ngx_string("tls13 quic key"), + &qsec->server.in.key, + &qsec->server.in.secret, + }, + { + ngx_string("tls13 quic iv"), + &qsec->server.in.iv, + &qsec->server.in.secret, + }, + { + /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */ + ngx_string("tls13 quic hp"), + &qsec->server.in.hp, + &qsec->server.in.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]; + + 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(ngx_pool_t *pool, 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; + + log = pool->log; // TODO: pass log ? + + out->len = in->len - EVP_GCM_TLS_TAG_LEN; + out->data = ngx_pnalloc(pool, out->len); + if (out->data == NULL) { + return NGX_ERROR; + } + +#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(ngx_pool_t *pool, 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; + + log = pool->log; // TODO: pass log ? + + out->len = in->len + EVP_GCM_TLS_TAG_LEN; + out->data = ngx_pnalloc(pool, out->len); + if (out->data == NULL) { + return NGX_ERROR; + } + +#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_peer_secrets_t *qsec) +{ + ngx_int_t key_len; + ngx_uint_t i; + ngx_quic_secret_t *peer_secret; + 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; + } + + switch (level) { + + case ssl_encryption_handshake: + peer_secret= &qsec->hs; + break; + + case ssl_encryption_application: + peer_secret = &qsec->ad; + break; + + default: + return 0; + } + + 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; +} + + +static ngx_int_t +ngx_quic_create_long_packet(ngx_pool_t *pool, ngx_ssl_conn_t *ssl_conn, + ngx_quic_header_t *pkt, ngx_str_t *payload, ngx_str_t *res) +{ + u_char *p, *pnp, *nonce, *sample, *packet; + uint64_t pn; + ngx_log_t *log; + ngx_str_t ad, out; + ngx_quic_ciphers_t ciphers; + u_char mask[16]; + + log = pool->log; + + out.len = payload->len + EVP_GCM_TLS_TAG_LEN; + + ad.data = ngx_alloc(346 /*max header*/, log); + if (ad.data == 0) { + return NGX_ERROR; + } + + p = ad.data; + + *p++ = pkt->flags; + + p = ngx_quic_write_uint32(p, quic_version); + + *p++ = pkt->scid.len; + p = ngx_cpymem(p, pkt->scid.data, pkt->scid.len); + + *p++ = pkt->dcid.len; + p = ngx_cpymem(p, pkt->dcid.data, pkt->dcid.len); + + if (pkt->level == ssl_encryption_initial) { + ngx_quic_build_int(&p, pkt->token.len); + } + + ngx_quic_build_int(&p, out.len + 1); // length (inc. pnl) + pnp = p; + + pn = *pkt->number; + + *p++ = pn; + + ad.len = p - ad.data; + + ngx_quic_hexdump0(log, "ad", ad.data, ad.len); + + if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { + return NGX_ERROR; + } + + nonce = ngx_pstrdup(pool, &pkt->secret->iv); + if (pkt->level == ssl_encryption_handshake) { + nonce[11] ^= pn; + } + + ngx_quic_hexdump0(log, "server_iv", pkt->secret->iv.data, 12); + ngx_quic_hexdump0(log, "nonce", nonce, 12); + + if (ngx_quic_tls_seal(pool, ciphers.c, pkt->secret, &out, + nonce, payload, &ad) + != NGX_OK) + { + return NGX_ERROR; + } + + sample = &out.data[3]; // pnl=0 + if (ngx_quic_tls_hp(log, ciphers.hp, pkt->secret, mask, sample) != NGX_OK) { + return NGX_ERROR; + } + + ngx_quic_hexdump0(log, "sample", sample, 16); + ngx_quic_hexdump0(log, "mask", mask, 16); + ngx_quic_hexdump0(log, "hp_key", pkt->secret->hp.data, 16); + + // header protection, pnl = 0 + ad.data[0] ^= mask[0] & 0x0f; + *pnp ^= mask[1]; + + packet = ngx_alloc(ad.len + out.len, log); + if (packet == 0) { + return NGX_ERROR; + } + + p = ngx_cpymem(packet, ad.data, ad.len); + p = ngx_cpymem(p, out.data, out.len); + + res->data = packet; + res->len = p - packet; + + return NGX_OK; +} + + +static ngx_int_t +ngx_quic_create_short_packet(ngx_pool_t *pool, ngx_ssl_conn_t *ssl_conn, + ngx_quic_header_t *pkt, ngx_str_t *payload, ngx_str_t *res) +{ + u_char *p, *pnp, *nonce, *sample, *packet; + ngx_log_t *log; + ngx_str_t ad, out; + ngx_quic_ciphers_t ciphers; + u_char mask[16]; + + log = pool->log; + + out.len = payload->len + EVP_GCM_TLS_TAG_LEN; + + ad.data = ngx_alloc(25 /*max header*/, log); + if (ad.data == 0) { + return NGX_ERROR; + } + + p = ad.data; + + *p++ = 0x40; + + p = ngx_cpymem(p, pkt->scid.data, pkt->scid.len); + + pnp = p; + + *p++ = (*pkt->number); + + ad.len = p - ad.data; + + ngx_quic_hexdump0(log, "ad", ad.data, ad.len); + + if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { + return NGX_ERROR; + } + + nonce = ngx_pstrdup(pool, &pkt->secret->iv); + if (pkt->level == ssl_encryption_handshake + || pkt->level == ssl_encryption_application) + { + nonce[11] ^= *pkt->number; + } + + ngx_quic_hexdump0(log, "server_iv", pkt->secret->iv.data, 12); + ngx_quic_hexdump0(log, "nonce", nonce, 12); + + if (ngx_quic_tls_seal(pool, ciphers.c, pkt->secret, &out, + nonce, payload, &ad) + != NGX_OK) + { + return NGX_ERROR; + } + + ngx_quic_hexdump0(log, "out", out.data, out.len); + + sample = &out.data[3]; // pnl=0 + if (ngx_quic_tls_hp(log, ciphers.hp, pkt->secret, mask, sample) != NGX_OK) { + return NGX_ERROR; + } + + ngx_quic_hexdump0(log, "sample", sample, 16); + ngx_quic_hexdump0(log, "mask", mask, 16); + ngx_quic_hexdump0(log, "hp_key", pkt->secret->hp.data, 16); + + // header protection, pnl = 0 + ad.data[0] ^= mask[0] & 0x1f; + *pnp ^= mask[1]; + + packet = ngx_alloc(ad.len + out.len, log); + if (packet == 0) { + return NGX_ERROR; + } + + p = ngx_cpymem(packet, ad.data, ad.len); + p = ngx_cpymem(p, out.data, out.len); + + ngx_quic_hexdump0(log, "packet", packet, p - packet); + + res->data = packet; + res->len = p - packet; + + return NGX_OK; +} + +static uint64_t +ngx_quic_parse_pn(u_char **pos, ngx_int_t len, u_char *mask) +{ + u_char *p; + uint64_t value; + + p = *pos; + value = *p++ ^ *mask++; + + while (--len) { + value = (value << 8) + (*p++ ^ *mask++); + } + + *pos = p; + return value; +} + + +ngx_int_t +ngx_quic_encrypt(ngx_pool_t *pool, ngx_ssl_conn_t *ssl_conn, + ngx_quic_header_t *pkt, ngx_str_t *payload, ngx_str_t *res) +{ + if (pkt->level == ssl_encryption_application) { + return ngx_quic_create_short_packet(pool, ssl_conn, pkt, payload, res); + } + + return ngx_quic_create_long_packet(pool, ssl_conn, pkt, payload, res); +} + + +ngx_int_t +ngx_quic_decrypt(ngx_pool_t *pool, ngx_ssl_conn_t *ssl_conn, + ngx_quic_header_t *pkt) +{ + u_char clearflags, *p, *sample; + uint8_t *nonce; + uint64_t pn; + ngx_log_t *log; + ngx_int_t pnl, rc; + ngx_str_t in, ad; + ngx_quic_ciphers_t ciphers; + uint8_t mask[16]; + + log = pool->log; + + if (ngx_quic_ciphers(ssl_conn, &ciphers, pkt->level) == NGX_ERROR) { + return NGX_ERROR; + } + + 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(log, "sample", sample, 16); + + /* header protection */ + + if (ngx_quic_tls_hp(log, ciphers.hp, pkt->secret, mask, sample) != NGX_OK) { + return NGX_ERROR; + } + + if (pkt->flags & NGX_QUIC_PKT_LONG) { + clearflags = pkt->flags ^ (mask[0] & 0x0f); + + } else { + clearflags = pkt->flags ^ (mask[0] & 0x1f); + } + + pnl = (clearflags & 0x03) + 1; + pn = ngx_quic_parse_pn(&p, pnl, &mask[1]); + + pkt->pn = pn; + + ngx_quic_hexdump0(log, "mask", mask, 5); + ngx_log_debug1(NGX_LOG_DEBUG_EVENT, log, 0, + "quic clear flags: %xi", clearflags); + ngx_log_debug2(NGX_LOG_DEBUG_EVENT, log, 0, + "quic packet number: %uL, len: %xi", pn, pnl); + + /* packet protection */ + + in.data = p; + + if (pkt->flags & NGX_QUIC_PKT_LONG) { + in.len = pkt->len - pnl; + + } else { + in.len = pkt->data + pkt->len - p; + } + + ad.len = p - pkt->data; + ad.data = ngx_pnalloc(pool, ad.len); + if (ad.data == NULL) { + return NGX_ERROR; + } + + 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); + + nonce = ngx_pstrdup(pool, &pkt->secret->iv); + nonce[11] ^= pn; + + ngx_quic_hexdump0(log, "nonce", nonce, 12); + ngx_quic_hexdump0(log, "ad", ad.data, ad.len); + + rc = ngx_quic_tls_open(pool, ciphers.c, pkt->secret, &pkt->payload, + nonce, &in, &ad); + + ngx_quic_hexdump0(log, "packet payload", + pkt->payload.data, pkt->payload.len); + + return rc; +} + |