diff options
Diffstat (limited to 'src/libknot/quic')
-rw-r--r-- | src/libknot/quic/quic.c | 343 | ||||
-rw-r--r-- | src/libknot/quic/quic.h | 59 | ||||
-rw-r--r-- | src/libknot/quic/quic_conn.c | 35 | ||||
-rw-r--r-- | src/libknot/quic/quic_conn.h | 20 | ||||
-rw-r--r-- | src/libknot/quic/tls.c | 262 | ||||
-rw-r--r-- | src/libknot/quic/tls.h | 135 | ||||
-rw-r--r-- | src/libknot/quic/tls_common.c | 472 | ||||
-rw-r--r-- | src/libknot/quic/tls_common.h | 134 |
8 files changed, 1071 insertions, 389 deletions
diff --git a/src/libknot/quic/quic.c b/src/libknot/quic/quic.c index f9d1d1d..4eb84c3 100644 --- a/src/libknot/quic/quic.c +++ b/src/libknot/quic/quic.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -33,7 +33,6 @@ #include "contrib/macros.h" #include "contrib/sockaddr.h" -#include "contrib/string.h" #include "contrib/ucw/lists.h" #include "libknot/endian.h" #include "libdnssec/error.h" @@ -58,19 +57,6 @@ #define TLS_CALLBACK_ERR (-1) -const gnutls_datum_t doq_alpn = { - (unsigned char *)"doq", 3 -}; - -typedef struct knot_quic_creds { - gnutls_certificate_credentials_t tls_cert; - gnutls_anti_replay_t tls_anti_replay; - gnutls_datum_t tls_ticket_key; - bool peer; - uint8_t peer_pin_len; - uint8_t peer_pin[]; -} knot_quic_creds_t; - typedef struct knot_quic_session { node_t n; gnutls_datum_t tls_session; @@ -153,223 +139,6 @@ session_free: return ret; } -static int tls_anti_replay_db_add_func(void *dbf, time_t exp_time, - const gnutls_datum_t *key, - const gnutls_datum_t *data) -{ - return 0; -} - -static void tls_session_ticket_key_free(gnutls_datum_t *ticket) -{ - gnutls_memset(ticket->data, 0, ticket->size); - gnutls_free(ticket->data); -} - -static int self_key(gnutls_x509_privkey_t *privkey, const char *key_file) -{ - gnutls_datum_t data = { 0 }; - - int ret = gnutls_x509_privkey_init(privkey); - if (ret != GNUTLS_E_SUCCESS) { - return ret; - } - - int fd = open(key_file, O_RDONLY); - if (fd != -1) { - struct stat stat; - if (fstat(fd, &stat) != 0 || - (data.data = gnutls_malloc(stat.st_size)) == NULL || - read(fd, data.data, stat.st_size) != stat.st_size) { - ret = GNUTLS_E_KEYFILE_ERROR; - goto finish; - } - - data.size = stat.st_size; - ret = gnutls_x509_privkey_import_pkcs8(*privkey, &data, GNUTLS_X509_FMT_PEM, - NULL, GNUTLS_PKCS_PLAIN); - if (ret != GNUTLS_E_SUCCESS) { - goto finish; - } - } else { - ret = gnutls_x509_privkey_generate(*privkey, GNUTLS_PK_EDDSA_ED25519, - GNUTLS_CURVE_TO_BITS(GNUTLS_ECC_CURVE_ED25519), 0); - if (ret != GNUTLS_E_SUCCESS) { - goto finish; - } - - ret = gnutls_x509_privkey_export2_pkcs8(*privkey, GNUTLS_X509_FMT_PEM, NULL, - GNUTLS_PKCS_PLAIN, &data); - if (ret != GNUTLS_E_SUCCESS || - (fd = open(key_file, O_WRONLY | O_CREAT, 0600)) == -1 || - write(fd, data.data, data.size) != data.size) { - ret = GNUTLS_E_KEYFILE_ERROR; - goto finish; - } - } - -finish: - close(fd); - gnutls_free(data.data); - if (ret != GNUTLS_E_SUCCESS) { - gnutls_x509_privkey_deinit(*privkey); - *privkey = NULL; - } - return ret; -} - -static int self_signed_cert(gnutls_certificate_credentials_t tls_cert, - const char *key_file) -{ - gnutls_x509_privkey_t privkey = NULL; - gnutls_x509_crt_t cert = NULL; - - char *hostname = sockaddr_hostname(); - if (hostname == NULL) { - return GNUTLS_E_MEMORY_ERROR; - } - - int ret; - uint8_t serial[16]; - gnutls_rnd(GNUTLS_RND_NONCE, serial, sizeof(serial)); - // Clear the left-most bit to be a positive number (two's complement form). - serial[0] &= 0x7F; - -#define CHK(cmd) if ((ret = (cmd)) != GNUTLS_E_SUCCESS) { goto finish; } -#define NOW_DAYS(days) (time(NULL) + 24 * 3600 * (days)) - - CHK(self_key(&privkey, key_file)); - - CHK(gnutls_x509_crt_init(&cert)); - CHK(gnutls_x509_crt_set_version(cert, 3)); - CHK(gnutls_x509_crt_set_serial(cert, serial, sizeof(serial))); - CHK(gnutls_x509_crt_set_activation_time(cert, NOW_DAYS(-1))); - CHK(gnutls_x509_crt_set_expiration_time(cert, NOW_DAYS(10 * 365))); - CHK(gnutls_x509_crt_set_dn_by_oid(cert, GNUTLS_OID_X520_COMMON_NAME, 0, - hostname, strlen(hostname))); - CHK(gnutls_x509_crt_set_key(cert, privkey)); - CHK(gnutls_x509_crt_sign2(cert, cert, privkey, GNUTLS_DIG_SHA512, 0)); - - ret = gnutls_certificate_set_x509_key(tls_cert, &cert, 1, privkey); - -finish: - free(hostname); - gnutls_x509_crt_deinit(cert); - gnutls_x509_privkey_deinit(privkey); - - return ret; -} - -_public_ -struct knot_quic_creds *knot_quic_init_creds(const char *cert_file, - const char *key_file) -{ - knot_quic_creds_t *creds = calloc(1, sizeof(*creds)); - if (creds == NULL) { - return NULL; - } - - int ret = gnutls_certificate_allocate_credentials(&creds->tls_cert); - if (ret != GNUTLS_E_SUCCESS) { - goto fail; - } - - ret = gnutls_anti_replay_init(&creds->tls_anti_replay); - if (ret != GNUTLS_E_SUCCESS) { - goto fail; - } - gnutls_anti_replay_set_add_function(creds->tls_anti_replay, tls_anti_replay_db_add_func); - gnutls_anti_replay_set_ptr(creds->tls_anti_replay, NULL); - - if (cert_file != NULL) { - ret = gnutls_certificate_set_x509_key_file(creds->tls_cert, - cert_file, key_file, - GNUTLS_X509_FMT_PEM); - } else { - ret = self_signed_cert(creds->tls_cert, key_file); - } - if (ret != GNUTLS_E_SUCCESS) { - goto fail; - } - - ret = gnutls_session_ticket_key_generate(&creds->tls_ticket_key); - if (ret != GNUTLS_E_SUCCESS) { - goto fail; - } - - return creds; -fail: - knot_quic_free_creds(creds); - return NULL; -} - -_public_ -struct knot_quic_creds *knot_quic_init_creds_peer(const struct knot_quic_creds *local_creds, - const uint8_t *peer_pin, - uint8_t peer_pin_len) -{ - knot_quic_creds_t *creds = calloc(1, sizeof(*creds) + peer_pin_len); - if (creds == NULL) { - return NULL; - } - - if (local_creds != NULL) { - creds->peer = true; - creds->tls_cert = local_creds->tls_cert; - } else { - int ret = gnutls_certificate_allocate_credentials(&creds->tls_cert); - if (ret != GNUTLS_E_SUCCESS) { - free(creds); - return NULL; - } - } - - if (peer_pin_len > 0 && peer_pin != NULL) { - memcpy(creds->peer_pin, peer_pin, peer_pin_len); - creds->peer_pin_len = peer_pin_len; - } - - return creds; -} - -_public_ -int knot_quic_creds_cert(struct knot_quic_creds *creds, struct gnutls_x509_crt_int **cert) -{ - if (creds == NULL || cert == NULL) { - return KNOT_EINVAL; - } - - gnutls_x509_crt_t *certs; - unsigned cert_count; - int ret = gnutls_certificate_get_x509_crt(creds->tls_cert, 0, &certs, &cert_count); - if (ret == GNUTLS_E_SUCCESS) { - if (cert_count == 0) { - gnutls_x509_crt_deinit(*certs); - return KNOT_ENOENT; - } - *cert = *certs; - free(certs); - } - return ret; -} - -_public_ -void knot_quic_free_creds(struct knot_quic_creds *creds) -{ - if (creds == NULL) { - return; - } - - if (!creds->peer && creds->tls_cert != NULL) { - gnutls_certificate_free_credentials(creds->tls_cert); - } - gnutls_anti_replay_deinit(creds->tls_anti_replay); - if (creds->tls_ticket_key.data != NULL) { - tls_session_ticket_key_free(&creds->tls_ticket_key); - } - free(creds); -} - static ngtcp2_conn *get_conn(ngtcp2_crypto_conn_ref *conn_ref) { return ((knot_quic_conn_t *)conn_ref->user_data)->conn; @@ -377,51 +146,31 @@ static ngtcp2_conn *get_conn(ngtcp2_crypto_conn_ref *conn_ref) static int tls_init_conn_session(knot_quic_conn_t *conn, bool server) { - if (gnutls_init(&conn->tls_session, (server ? GNUTLS_SERVER : GNUTLS_CLIENT) | - GNUTLS_ENABLE_EARLY_DATA | GNUTLS_NO_AUTO_SEND_TICKET | - GNUTLS_NO_END_OF_EARLY_DATA) != GNUTLS_E_SUCCESS) { - return TLS_CALLBACK_ERR; - } - - gnutls_certificate_send_x509_rdn_sequence(conn->tls_session, 1); - gnutls_certificate_server_set_request(conn->tls_session, GNUTLS_CERT_REQUEST); - - if (gnutls_priority_set_direct(conn->tls_session, QUIC_PRIORITIES, - NULL) != GNUTLS_E_SUCCESS) { + int ret = knot_tls_session(&conn->tls_session, conn->quic_table->creds, + conn->quic_table->priority, "\x03""doq", + true, server); + if (ret != KNOT_EOK) { return TLS_CALLBACK_ERR; } - if (server && gnutls_session_ticket_enable_server(conn->tls_session, - &conn->quic_table->creds->tls_ticket_key) != GNUTLS_E_SUCCESS) { - return TLS_CALLBACK_ERR; + if (server) { + ret = ngtcp2_crypto_gnutls_configure_server_session(conn->tls_session); + } else { + ret = ngtcp2_crypto_gnutls_configure_client_session(conn->tls_session); } - - int ret = ngtcp2_crypto_gnutls_configure_server_session(conn->tls_session); - if (ret != 0) { + if (ret != NGTCP2_NO_ERROR) { return TLS_CALLBACK_ERR; } - gnutls_record_set_max_early_data_size(conn->tls_session, 0xffffffffu); - conn->conn_ref = (nc_conn_ref_placeholder_t) { .get_conn = get_conn, .user_data = conn }; - _Static_assert(sizeof(nc_conn_ref_placeholder_t) == sizeof(ngtcp2_crypto_conn_ref), "invalid placeholder for conn_ref"); + _Static_assert(sizeof(nc_conn_ref_placeholder_t) == sizeof(ngtcp2_crypto_conn_ref), + "invalid placeholder for conn_ref"); gnutls_session_set_ptr(conn->tls_session, &conn->conn_ref); - if (server) { - gnutls_anti_replay_enable(conn->tls_session, conn->quic_table->creds->tls_anti_replay); - - } - if (gnutls_credentials_set(conn->tls_session, GNUTLS_CRD_CERTIFICATE, - conn->quic_table->creds->tls_cert) != GNUTLS_E_SUCCESS) { - return TLS_CALLBACK_ERR; - } - - gnutls_alpn_set_protocols(conn->tls_session, &doq_alpn, 1, GNUTLS_ALPN_MANDATORY); - ngtcp2_conn_set_tls_native_handle(conn->conn, conn->tls_session); return KNOT_EOK; @@ -477,54 +226,6 @@ uint16_t knot_quic_conn_local_port(knot_quic_conn_t *conn) return ((const struct sockaddr_in6 *)path->local.addr)->sin6_port; } -_public_ -void knot_quic_conn_pin(knot_quic_conn_t *conn, uint8_t *pin, size_t *pin_size, bool local) -{ - if (conn == NULL) { - goto error; - } - - const gnutls_datum_t *data = NULL; - if (local) { - data = gnutls_certificate_get_ours(conn->tls_session); - } else { - unsigned count = 0; - data = gnutls_certificate_get_peers(conn->tls_session, &count); - if (count == 0) { - goto error; - } - } - if (data == NULL) { - goto error; - } - - gnutls_x509_crt_t cert; - int ret = gnutls_x509_crt_init(&cert); - if (ret != GNUTLS_E_SUCCESS) { - goto error; - } - - ret = gnutls_x509_crt_import(cert, data, GNUTLS_X509_FMT_DER); - if (ret != GNUTLS_E_SUCCESS) { - gnutls_x509_crt_deinit(cert); - goto error; - } - - ret = gnutls_x509_crt_get_key_id(cert, GNUTLS_KEYID_USE_SHA256, pin, pin_size); - if (ret != GNUTLS_E_SUCCESS) { - gnutls_x509_crt_deinit(cert); - goto error; - } - - gnutls_x509_crt_deinit(cert); - - return; -error: - if (pin_size != NULL) { - *pin_size = 0; - } -} - static void knot_quic_rand_cb(uint8_t *dest, size_t destlen, const ngtcp2_rand_ctx *rand_ctx) { (void)rand_ctx; @@ -602,18 +303,8 @@ static int handshake_completed_cb(ngtcp2_conn *conn, void *user_data) ctx->flags |= KNOT_QUIC_CONN_HANDSHAKE_DONE; if (!ngtcp2_conn_is_server(conn)) { - knot_quic_creds_t *creds = ctx->quic_table->creds; - if (creds->peer_pin_len == 0) { - return 0; - } - uint8_t pin[KNOT_QUIC_PIN_LEN]; - size_t pin_size = sizeof(pin); - knot_quic_conn_pin(ctx, pin, &pin_size, false); - if (pin_size != creds->peer_pin_len || - const_time_memcmp(pin, creds->peer_pin, pin_size) != 0) { - return NGTCP2_ERR_CALLBACK_FAILURE; - } - return 0; + return knot_tls_pin_check(ctx->tls_session, ctx->quic_table->creds) + == KNOT_EOK ? 0 : NGTCP2_ERR_CALLBACK_FAILURE; } if (gnutls_session_ticket_send(ctx->tls_session, 1, 0) != GNUTLS_E_SUCCESS) { @@ -945,6 +636,10 @@ int knot_quic_handle(knot_quic_table_t *table, knot_quic_reply_t *reply, goto finish; } + if (conn != NULL && (conn->flags & KNOT_QUIC_CONN_BLOCKED)) { + return KNOT_EOK; + } + ngtcp2_path path; path.remote.addr = (struct sockaddr *)reply->ip_rem; path.remote.addrlen = addr_len((struct sockaddr_in6 *)reply->ip_rem); @@ -1249,6 +944,8 @@ int knot_quic_send(knot_quic_table_t *quic_table, knot_quic_conn_t *conn, return KNOT_EINVAL; } else if (reply->handle_ret < 0) { return reply->handle_ret; + } else if ((conn->flags & KNOT_QUIC_CONN_BLOCKED) && !(flags & KNOT_QUIC_SEND_IGNORE_BLOCKED)) { + return KNOT_EOK; } else if (reply->handle_ret > 0) { return send_special(quic_table, reply, conn); } else if (conn == NULL) { diff --git a/src/libknot/quic/quic.h b/src/libknot/quic/quic.h index 29a02e0..b4acb33 100644 --- a/src/libknot/quic/quic.h +++ b/src/libknot/quic/quic.h @@ -1,4 +1,4 @@ -/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -29,20 +29,18 @@ #include <netinet/in.h> #include "libknot/quic/quic_conn.h" - -#define KNOT_QUIC_PIN_LEN 32 +#include "libknot/quic/tls_common.h" #define KNOT_QUIC_HANDLE_RET_CLOSE 2000 // RFC 9250 #define KNOT_QUIC_ERR_EXCESSIVE_LOAD 0x4 -struct gnutls_x509_crt_int; -struct knot_quic_creds; struct knot_quic_session; typedef enum { KNOT_QUIC_SEND_IGNORE_LASTBYTE = (1 << 0), + KNOT_QUIC_SEND_IGNORE_BLOCKED = (1 << 1), } knot_quic_send_flag_t; typedef struct knot_quic_reply { @@ -87,45 +85,6 @@ struct knot_quic_session *knot_quic_session_save(knot_quic_conn_t *conn); int knot_quic_session_load(knot_quic_conn_t *conn, struct knot_quic_session *session); /*! - * \brief Init server TLS certificate for DoQ. - * - * \param cert_file X509 certificate PEM file path/name (NULL if auto-generated). - * \param key_file Key PEM file path/name. - * - * \return Initialized creds. - */ -struct knot_quic_creds *knot_quic_init_creds(const char *cert_file, - const char *key_file); - -/*! - * \brief Init peer TLS certificate for DoQ. - * - * \param local_creds Local credentials if server. - * \param peer_pin Optional peer certificate pin to check. - * \param peer_pin_len Length of the peer pin. Set 0 if not specified. - * - * \return Initialized creds. - */ -struct knot_quic_creds *knot_quic_init_creds_peer(const struct knot_quic_creds *local_creds, - const uint8_t *peer_pin, - uint8_t peer_pin_len); - -/*! - * \brief Gets the certificate from credentials. - * - * \param creds TLS credentials. - * \param cert Output certificate. - * - * \return KNOT_E* - */ -int knot_quic_creds_cert(struct knot_quic_creds *creds, struct gnutls_x509_crt_int **cert); - -/*! - * \brief Deinit server TLS certificate for DoQ. - */ -void knot_quic_free_creds(struct knot_quic_creds *creds); - -/*! * \brief Returns timeout value for the connection. */ uint64_t quic_conn_get_timeout(knot_quic_conn_t *conn); @@ -156,18 +115,6 @@ uint32_t knot_quic_conn_rtt(knot_quic_conn_t *conn); uint16_t knot_quic_conn_local_port(knot_quic_conn_t *conn); /*! - * \brief Gets local or remote certificate pin. - * - * \note Zero output pin_size value means no certificate available or error. - * - * \param conn QUIC connection. - * \param pin Output certificate pin. - * \param pin_size Input size of the storage / output size of the stored pin. - * \param local Local or remote certificate indication. - */ -void knot_quic_conn_pin(knot_quic_conn_t *conn, uint8_t *pin, size_t *pin_size, bool local); - -/*! * \brief Create new outgoing QUIC connection. * * \param table QUIC connections table to be added to. diff --git a/src/libknot/quic/quic_conn.c b/src/libknot/quic/quic_conn.c index 6616573..1a3b9df 100644 --- a/src/libknot/quic/quic_conn.c +++ b/src/libknot/quic/quic_conn.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -29,6 +29,7 @@ #include "libdnssec/random.h" #include "libknot/attribute.h" #include "libknot/error.h" +#include "libknot/quic/tls_common.h" #include "libknot/quic/quic.h" #include "libknot/xdp/tcp_iobuf.h" #include "libknot/wire.h" @@ -45,7 +46,7 @@ static int cmp_expiry_heap_nodes(void *c1, void *c2) _public_ knot_quic_table_t *knot_quic_table_new(size_t max_conns, size_t max_ibufs, size_t max_obufs, - size_t udp_payload, struct knot_quic_creds *creds) + size_t udp_payload, struct knot_creds *creds) { size_t table_size = max_conns * BUCKETS_PER_CONNS; @@ -61,9 +62,17 @@ knot_quic_table_t *knot_quic_table_new(size_t max_conns, size_t max_ibufs, size_ res->obufs_max = max_obufs; res->udp_payload_limit = udp_payload; + int ret = gnutls_priority_init2(&res->priority, KNOT_TLS_PRIORITIES, NULL, + GNUTLS_PRIORITY_INIT_DEF_APPEND); + if (ret != GNUTLS_E_SUCCESS) { + free(res); + return NULL; + } + res->expiry_heap = malloc(sizeof(struct heap)); if (res->expiry_heap == NULL || !heap_init(res->expiry_heap, cmp_expiry_heap_nodes, 0)) { free(res->expiry_heap); + gnutls_priority_deinit(res->priority); free(res); return NULL; } @@ -92,6 +101,7 @@ void knot_quic_table_free(knot_quic_table_t *table) assert(table->ibufs_size == 0); assert(table->obufs_size == 0); + gnutls_priority_deinit(table->priority); heap_deinit(table->expiry_heap); free(table->expiry_heap); free(table); @@ -118,7 +128,9 @@ void knot_quic_table_sweep(knot_quic_table_t *table, struct knot_quic_reply *swe while (!EMPTY_HEAP(table->expiry_heap)) { knot_quic_conn_t *c = *(knot_quic_conn_t **)HHEAD(table->expiry_heap); - if (table->usage > table->max_conns) { + if ((c->flags & KNOT_QUIC_CONN_BLOCKED)) { + break; // highly inprobable + } else if (table->usage > table->max_conns) { knot_sweep_stats_incr(stats, KNOT_SWEEP_CTR_LIMIT_CONN); send_excessive_load(c, sweep_reply, table); knot_quic_table_rem(c, table); @@ -476,7 +488,7 @@ uint8_t *knot_quic_stream_add_data(knot_quic_conn_t *conn, int64_t stream_id, add_tail((list_t *)&s->outbufs, (node_t *)obuf); s->obufs_size += obuf->len; conn->obufs_size += obuf->len; - conn->quic_table->obufs_size += obuf->len; + ATOMIC_ADD(conn->quic_table->obufs_size, obuf->len); return obuf->buf + prefix; } @@ -497,7 +509,7 @@ void knot_quic_stream_ack_data(knot_quic_conn_t *conn, int64_t stream_id, assert(HEAD(*obs) != first); // help CLANG analyzer understand what rem_node did and that further usage of HEAD(*obs) is safe s->obufs_size -= first->len; conn->obufs_size -= first->len; - conn->quic_table->obufs_size -= first->len; + ATOMIC_SUB(conn->quic_table->obufs_size, first->len); s->first_offset += first->len; free(first); if (s->unsent_obuf == first) { @@ -556,6 +568,19 @@ void knot_quic_stream_mark_sent(knot_quic_conn_t *conn, int64_t stream_id, } _public_ +void knot_quic_conn_block(knot_quic_conn_t *conn, bool block) +{ + if (block) { + conn->flags |= KNOT_QUIC_CONN_BLOCKED; + conn->next_expiry = UINT64_MAX; + conn_heap_reschedule(conn, conn->quic_table); + } else { + conn->flags &= ~KNOT_QUIC_CONN_BLOCKED; + quic_conn_mark_used(conn, conn->quic_table); + } +} + +_public_ void knot_quic_cleanup(knot_quic_conn_t *conns[], size_t n_conns) { for (size_t i = 0; i < n_conns; i++) { diff --git a/src/libknot/quic/quic_conn.h b/src/libknot/quic/quic_conn.h index 64ead51..49e0631 100644 --- a/src/libknot/quic/quic_conn.h +++ b/src/libknot/quic/quic_conn.h @@ -1,4 +1,4 @@ -/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -29,10 +29,13 @@ #include <stdint.h> #include <sys/uio.h> +#include "contrib/atomic.h" + #define MAX_STREAMS_PER_CONN 10 // this limits the number of un-finished streams per conn (i.e. if response has been recvd with FIN, it doesn't count) +struct gnutls_priority_st; struct ngtcp2_cid; // declaration taken from wherever in ngtcp2 -struct knot_quic_creds; +struct knot_creds; struct knot_quic_reply; struct knot_sweep_stats; @@ -70,6 +73,7 @@ typedef struct { typedef enum { KNOT_QUIC_CONN_HANDSHAKE_DONE = (1 << 0), KNOT_QUIC_CONN_SESSION_TAKEN = (1 << 1), + KNOT_QUIC_CONN_BLOCKED = (1 << 2), } knot_quic_conn_flag_t; typedef struct knot_quic_conn { @@ -111,12 +115,13 @@ typedef struct knot_quic_table { size_t ibufs_max; size_t obufs_max; size_t ibufs_size; - size_t obufs_size; + knot_atomic_size_t obufs_size; size_t udp_payload_limit; // for simplicity not distinguishing IPv4/6 void (*log_cb)(const char *); const char *qlog_dir; uint64_t hash_secret[4]; - struct knot_quic_creds *creds; + struct knot_creds *creds; + struct gnutls_priority_st *priority; struct heap *expiry_heap; knot_quic_cid_t *conns[]; } knot_quic_table_t; @@ -133,7 +138,7 @@ typedef struct knot_quic_table { * \return Allocated table, or NULL. */ knot_quic_table_t *knot_quic_table_new(size_t max_conns, size_t max_ibufs, size_t max_obufs, - size_t udp_payload, struct knot_quic_creds *creds); + size_t udp_payload, struct knot_creds *creds); /*! * \brief Free QUIC table including its contents. @@ -306,6 +311,11 @@ void knot_quic_stream_mark_sent(knot_quic_conn_t *conn, int64_t stream_id, size_t amount_sent); /*! + * \brief (Un)block the connection for incoming/outgoing traffic and sweep. + */ +void knot_quic_conn_block(knot_quic_conn_t *conn, bool block); + +/*! * \brief Free rest of resources of closed conns. * * \param conns Array with recently used conns (possibly NULLs). diff --git a/src/libknot/quic/tls.c b/src/libknot/quic/tls.c new file mode 100644 index 0000000..01172df --- /dev/null +++ b/src/libknot/quic/tls.c @@ -0,0 +1,262 @@ +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <arpa/inet.h> +#include <assert.h> +#include <gnutls/crypto.h> +#include <gnutls/gnutls.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/socket.h> + +#include "libknot/quic/tls.h" + +#include "contrib/macros.h" +#include "contrib/time.h" +#include "libknot/attribute.h" +#include "libknot/error.h" +#include "libknot/quic/tls_common.h" + +_public_ +knot_tls_ctx_t *knot_tls_ctx_new(struct knot_creds *creds, unsigned io_timeout, + unsigned hs_timeout, bool server) +{ + knot_tls_ctx_t *res = calloc(1, sizeof(*res)); + if (res == NULL) { + return NULL; + } + + res->creds = creds; + res->handshake_timeout = hs_timeout; + res->io_timeout = io_timeout; + res->server = server; + + int ret = gnutls_priority_init2(&res->priority, KNOT_TLS_PRIORITIES, NULL, + GNUTLS_PRIORITY_INIT_DEF_APPEND); + if (ret != GNUTLS_E_SUCCESS) { + free(res); + return NULL; + } + + return res; +} + +_public_ +void knot_tls_ctx_free(knot_tls_ctx_t *ctx) +{ + if (ctx != NULL) { + gnutls_priority_deinit(ctx->priority); + free(ctx); + } +} + +_public_ +knot_tls_conn_t *knot_tls_conn_new(knot_tls_ctx_t *ctx, int sock_fd) +{ + knot_tls_conn_t *res = calloc(1, sizeof(*res)); + if (res == NULL) { + return NULL; + } + res->ctx = ctx; + res->fd = sock_fd; + + int ret = knot_tls_session(&res->session, ctx->creds, ctx->priority, + "\x03""dot", false, ctx->server); + if (ret != KNOT_EOK) { + goto fail; + } + + gnutls_transport_set_int(res->session, sock_fd); // Use internal recv/send/poll. + gnutls_handshake_set_timeout(res->session, ctx->handshake_timeout); + + return res; +fail: + gnutls_deinit(res->session); + free(res); + return NULL; +} + +_public_ +void knot_tls_conn_del(knot_tls_conn_t *conn) +{ + if (conn != NULL && conn->fd_clones_count-- < 1) { + gnutls_deinit(conn->session); + free(conn); + } +} + +_public_ +int knot_tls_handshake(knot_tls_conn_t *conn, bool oneshot) +{ + if (conn->flags & (KNOT_TLS_CONN_HANDSHAKE_DONE | KNOT_TLS_CONN_BLOCKED)) { + return KNOT_EOK; + } + + /* Check if NB socket is writeable. */ + int opt; + socklen_t opt_len = sizeof(opt); + int ret = getsockopt(conn->fd, SOL_SOCKET, SO_ERROR, &opt, &opt_len); + if (ret < 0 || opt == ECONNREFUSED) { + return KNOT_NET_ECONNECT; + } + + gnutls_record_set_timeout(conn->session, conn->ctx->io_timeout); + do { + ret = gnutls_handshake(conn->session); + } while (!oneshot && ret < 0 && gnutls_error_is_fatal(ret) == 0); + + switch (ret) { + case GNUTLS_E_SUCCESS: + conn->flags |= KNOT_TLS_CONN_HANDSHAKE_DONE; + return knot_tls_pin_check(conn->session, conn->ctx->creds); + case GNUTLS_E_TIMEDOUT: + return KNOT_NET_ETIMEOUT; + default: + if (gnutls_error_is_fatal(ret) == 0) { + return KNOT_EAGAIN; + } else { + return KNOT_NET_EHSHAKE; + } + } +} + +#define TIMEOUT_CTX_INIT \ + struct timespec begin, end; \ + if (*timeout_ptr > 0) { \ + clock_gettime(CLOCK_MONOTONIC, &begin); \ + } + +#define TIMEOUT_CTX_UPDATE \ + if (*timeout_ptr > 0) { \ + clock_gettime(CLOCK_MONOTONIC, &end); \ + int running_ms = time_diff_ms(&begin, &end); \ + *timeout_ptr = MAX(*timeout_ptr - running_ms, 0); \ + } + +static ssize_t recv_data(knot_tls_conn_t *conn, void *data, size_t size, int *timeout_ptr) +{ + gnutls_record_set_timeout(conn->session, *timeout_ptr); + + size_t total = 0; + ssize_t res; + while (total < size) { + TIMEOUT_CTX_INIT + res = gnutls_record_recv(conn->session, data + total, size - total); + if (res > 0) { + total += res; + } else if (res == 0) { + return KNOT_ECONNRESET; + } else if (gnutls_error_is_fatal(res) != 0) { + return KNOT_NET_ERECV; + } + TIMEOUT_CTX_UPDATE + gnutls_record_set_timeout(conn->session, *timeout_ptr); + } + + assert(total == size); + return size; +} + +_public_ +ssize_t knot_tls_recv_dns(knot_tls_conn_t *conn, void *data, size_t size) +{ + if (conn == NULL || data == NULL) { + return KNOT_EINVAL; + } + + if (conn->flags & KNOT_TLS_CONN_BLOCKED) { + return 0; + } + + ssize_t ret = knot_tls_handshake(conn, false); + if (ret != KNOT_EOK) { + return ret; + } + + int timeout = conn->ctx->io_timeout; + + uint16_t msg_len; + ret = recv_data(conn, &msg_len, sizeof(msg_len), &timeout); + if (ret != sizeof(msg_len)) { + return ret; + } + + msg_len = ntohs(msg_len); + if (size < msg_len) { + return KNOT_ESPACE; + } + + ret = recv_data(conn, data, msg_len, &timeout); + if (ret != size) { + return ret; + } + + return msg_len; +} + +_public_ +ssize_t knot_tls_send_dns(knot_tls_conn_t *conn, void *data, size_t size) +{ + if (conn == NULL || data == NULL || size > UINT16_MAX) { + return KNOT_EINVAL; + } + + ssize_t res = knot_tls_handshake(conn, false); + if (res != KNOT_EOK) { + return res; + } + + // Enable data buffering. + gnutls_record_cork(conn->session); + + uint16_t msg_len = htons(size); + res = gnutls_record_send(conn->session, &msg_len, sizeof(msg_len)); + if (res != sizeof(msg_len)) { + return KNOT_NET_ESEND; + } + + res = gnutls_record_send(conn->session, data, size); + if (res != size) { + return KNOT_NET_ESEND; + } + + int timeout = conn->ctx->io_timeout, *timeout_ptr = &timeout; + gnutls_record_set_timeout(conn->session, timeout); + + // Send the buffered data. + while (gnutls_record_check_corked(conn->session) > 0) { + TIMEOUT_CTX_INIT + int ret = gnutls_record_uncork(conn->session, 0); + if (ret < 0 && gnutls_error_is_fatal(ret) != 0) { + return ret == GNUTLS_E_TIMEDOUT ? KNOT_ETIMEOUT : + KNOT_NET_ESEND; + } + TIMEOUT_CTX_UPDATE + gnutls_record_set_timeout(conn->session, timeout); + } + + return size; +} + +_public_ +void knot_tls_conn_block(knot_tls_conn_t *conn, bool block) +{ + if (block) { + conn->flags |= KNOT_TLS_CONN_BLOCKED; + } else { + conn->flags &= ~KNOT_TLS_CONN_BLOCKED; + } +} diff --git a/src/libknot/quic/tls.h b/src/libknot/quic/tls.h new file mode 100644 index 0000000..7801ca8 --- /dev/null +++ b/src/libknot/quic/tls.h @@ -0,0 +1,135 @@ +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +/*! + * \file + * + * \brief Pure TLS functionality. + * + * \addtogroup quic + * @{ + */ + +#pragma once + +#include <stdbool.h> +#include <stdint.h> +#include <sys/types.h> + +struct gnutls_priority_st; + +typedef enum { + KNOT_TLS_CONN_HANDSHAKE_DONE = (1 << 0), + KNOT_TLS_CONN_SESSION_TAKEN = (1 << 1), // unused, to be implemeted later + KNOT_TLS_CONN_BLOCKED = (1 << 2), +} knot_tls_conn_flag_t; + +typedef struct knot_tls_ctx { + struct knot_creds *creds; + struct gnutls_priority_st *priority; + unsigned handshake_timeout; + unsigned io_timeout; + bool server; +} knot_tls_ctx_t; + +typedef struct knot_tls_conn { + struct gnutls_session_int *session; + struct knot_tls_ctx *ctx; + int fd; + unsigned fd_clones_count; + knot_tls_conn_flag_t flags; +} knot_tls_conn_t; + +/*! + * \brief Initialize DoT answering context. + * + * \param creds Certificate credentials. + * \param io_timeout Connections' IO-timeout (in milliseconds). + * \param hs_timeout Handshake timeout (in milliseconds). + * \param server Server context (otherwise client). + * + * \return Initialized context or NULL. + */ +knot_tls_ctx_t *knot_tls_ctx_new(struct knot_creds *creds, unsigned io_timeout, + unsigned hs_timeout, bool server); + +/*! + * \brief Free DoT answering context. + */ +void knot_tls_ctx_free(knot_tls_ctx_t *ctx); + +/*! + * \brief Initialize DoT connection. + * + * \param ctx DoT answering context. + * \param sock_fd Opened TCP connection socket. + * + * \return Connection struct or NULL. + */ +knot_tls_conn_t *knot_tls_conn_new(knot_tls_ctx_t *ctx, int sock_fd); + +/*! + * \brief Free DoT connection struct. + * + * \note Doesn't close the TCP connection socket. + */ +void knot_tls_conn_del(knot_tls_conn_t *conn); + +/*! + * \brief Perform the TLS handshake (via gnutls_handshake()). + * + * \note This is also done by the recv/send functions. + * + * \param conn DoT connection. + * \param oneshot If set, don't wait untill the handshake is finished. + * + * \retval KNOT_EOK Handshake successfully finished. + * \retval KNOT_EGAIN Handshake not finished, call me again. + * \retval KNOT_NET_EHSHAKE Handshake error. + * \retval KNOT_NET_ECONNECT Socket not connected. + */ +int knot_tls_handshake(knot_tls_conn_t *conn, bool oneshot); + +/*! + * \brief Receive a size-word-prefixed DNS message. + * + * \param conn DoT connection. + * \param data Destination buffer. + * \param size Maximum buffer size. + * + * \return Either the DNS message size received or negative error code. + * + * \note The two-byte-size-prefix is stripped upon reception, not stored to the buffer. + */ +ssize_t knot_tls_recv_dns(knot_tls_conn_t *conn, void *data, size_t size); + +/*! + * \brief Send a size-word-prefixed DNS message. + * + * \param conn DoT connection. + * \param data DNS payload. + * \param size Payload size. + * + * \return Either exactly 'size' or a negative error code. + */ +ssize_t knot_tls_send_dns(knot_tls_conn_t *conn, void *data, size_t size); + +/*! + * \brief Set or unset the conection's BLOCKED flag. + */ +void knot_tls_conn_block(knot_tls_conn_t *conn, bool block); + +/*! @} */ diff --git a/src/libknot/quic/tls_common.c b/src/libknot/quic/tls_common.c new file mode 100644 index 0000000..d1647d8 --- /dev/null +++ b/src/libknot/quic/tls_common.c @@ -0,0 +1,472 @@ +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <fcntl.h> +#include <gnutls/crypto.h> +#include <gnutls/gnutls.h> +#include <gnutls/x509.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <time.h> +#include <unistd.h> + +#include "libknot/quic/tls_common.h" + +#include "contrib/atomic.h" +#include "contrib/sockaddr.h" +#include "contrib/string.h" +#include "libknot/attribute.h" +#include "libknot/error.h" + +typedef struct knot_creds { + knot_atomic_ptr_t cert_creds; // Current credentials. + gnutls_certificate_credentials_t cert_creds_prev; // Previous credentials (for pending connections). + gnutls_anti_replay_t tls_anti_replay; + gnutls_datum_t tls_ticket_key; + bool peer; + uint8_t peer_pin_len; + uint8_t peer_pin[]; +} knot_creds_t; + +static int tls_anti_replay_db_add_func(void *dbf, time_t exp_time, + const gnutls_datum_t *key, + const gnutls_datum_t *data) +{ + return 0; +} + +static void tls_session_ticket_key_free(gnutls_datum_t *ticket) +{ + memzero(ticket->data, ticket->size); + gnutls_free(ticket->data); +} + +static int self_key(gnutls_x509_privkey_t *privkey, const char *key_file) +{ + gnutls_datum_t data = { 0 }; + + int ret = gnutls_x509_privkey_init(privkey); + if (ret != GNUTLS_E_SUCCESS) { + return ret; + } + + int fd = open(key_file, O_RDONLY); + if (fd != -1) { + struct stat stat; + if (fstat(fd, &stat) != 0 || + (data.data = gnutls_malloc(stat.st_size)) == NULL || + read(fd, data.data, stat.st_size) != stat.st_size) { + ret = GNUTLS_E_KEYFILE_ERROR; + goto finish; + } + + data.size = stat.st_size; + ret = gnutls_x509_privkey_import_pkcs8(*privkey, &data, GNUTLS_X509_FMT_PEM, + NULL, GNUTLS_PKCS_PLAIN); + if (ret != GNUTLS_E_SUCCESS) { + goto finish; + } + } else { + ret = gnutls_x509_privkey_generate(*privkey, GNUTLS_PK_EDDSA_ED25519, + GNUTLS_CURVE_TO_BITS(GNUTLS_ECC_CURVE_ED25519), 0); + if (ret != GNUTLS_E_SUCCESS) { + goto finish; + } + + ret = gnutls_x509_privkey_export2_pkcs8(*privkey, GNUTLS_X509_FMT_PEM, NULL, + GNUTLS_PKCS_PLAIN, &data); + if (ret != GNUTLS_E_SUCCESS || + (fd = open(key_file, O_WRONLY | O_CREAT, 0600)) == -1 || + write(fd, data.data, data.size) != data.size) { + ret = GNUTLS_E_KEYFILE_ERROR; + goto finish; + } + } + +finish: + if (fd > -1) { + close(fd); + } + gnutls_free(data.data); + if (ret != GNUTLS_E_SUCCESS) { + gnutls_x509_privkey_deinit(*privkey); + *privkey = NULL; + } + return ret; +} + +static int self_signed_cert(gnutls_certificate_credentials_t tls_cert, + const char *key_file) +{ + gnutls_x509_privkey_t privkey = NULL; + gnutls_x509_crt_t cert = NULL; + + char *hostname = sockaddr_hostname(); + if (hostname == NULL) { + return GNUTLS_E_MEMORY_ERROR; + } + + int ret; + uint8_t serial[16]; + gnutls_rnd(GNUTLS_RND_NONCE, serial, sizeof(serial)); + // Clear the left-most bit to be a positive number (two's complement form). + serial[0] &= 0x7F; + +#define CHK(cmd) if ((ret = (cmd)) != GNUTLS_E_SUCCESS) { goto finish; } +#define NOW_DAYS(days) (time(NULL) + 24 * 3600 * (days)) + + CHK(self_key(&privkey, key_file)); + + CHK(gnutls_x509_crt_init(&cert)); + CHK(gnutls_x509_crt_set_version(cert, 3)); + CHK(gnutls_x509_crt_set_serial(cert, serial, sizeof(serial))); + CHK(gnutls_x509_crt_set_activation_time(cert, NOW_DAYS(-1))); + CHK(gnutls_x509_crt_set_expiration_time(cert, NOW_DAYS(10 * 365))); + CHK(gnutls_x509_crt_set_dn_by_oid(cert, GNUTLS_OID_X520_COMMON_NAME, 0, + hostname, strlen(hostname))); + CHK(gnutls_x509_crt_set_key(cert, privkey)); + CHK(gnutls_x509_crt_sign2(cert, cert, privkey, GNUTLS_DIG_SHA512, 0)); + + ret = gnutls_certificate_set_x509_key(tls_cert, &cert, 1, privkey); + +finish: + free(hostname); + gnutls_x509_crt_deinit(cert); + gnutls_x509_privkey_deinit(privkey); + + return ret; +} + +_public_ +struct knot_creds *knot_creds_init(const char *key_file, const char *cert_file) +{ + knot_creds_t *creds = calloc(1, sizeof(*creds)); + if (creds == NULL) { + return NULL; + } + + int ret = knot_creds_update(creds, key_file, cert_file); + if (ret != KNOT_EOK) { + goto fail; + } + + ret = gnutls_anti_replay_init(&creds->tls_anti_replay); + if (ret != GNUTLS_E_SUCCESS) { + goto fail; + } + gnutls_anti_replay_set_add_function(creds->tls_anti_replay, tls_anti_replay_db_add_func); + gnutls_anti_replay_set_ptr(creds->tls_anti_replay, NULL); + + ret = gnutls_session_ticket_key_generate(&creds->tls_ticket_key); + if (ret != GNUTLS_E_SUCCESS) { + goto fail; + } + + return creds; +fail: + knot_creds_free(creds); + return NULL; +} + +_public_ +struct knot_creds *knot_creds_init_peer(const struct knot_creds *local_creds, + const uint8_t *peer_pin, + uint8_t peer_pin_len) +{ + knot_creds_t *creds = calloc(1, sizeof(*creds) + peer_pin_len); + if (creds == NULL) { + return NULL; + } + + if (local_creds != NULL) { + creds->peer = true; + creds->cert_creds = ATOMIC_GET(local_creds->cert_creds); + } else { + gnutls_certificate_credentials_t new_creds; + int ret = gnutls_certificate_allocate_credentials(&new_creds); + if (ret != GNUTLS_E_SUCCESS) { + free(creds); + return NULL; + } + creds->cert_creds = new_creds; + } + + if (peer_pin_len > 0 && peer_pin != NULL) { + memcpy(creds->peer_pin, peer_pin, peer_pin_len); + creds->peer_pin_len = peer_pin_len; + } + + return creds; +} + +static int creds_cert(gnutls_certificate_credentials_t creds, + struct gnutls_x509_crt_int **cert) +{ + gnutls_x509_crt_t *certs; + unsigned cert_count; + int ret = gnutls_certificate_get_x509_crt(creds, 0, &certs, &cert_count); + if (ret == GNUTLS_E_SUCCESS) { + if (cert_count == 0) { + gnutls_x509_crt_deinit(*certs); + return KNOT_ENOENT; + } + *cert = *certs; + free(certs); + return KNOT_EOK; + } + return KNOT_ERROR; +} + +static int creds_changed(gnutls_certificate_credentials_t creds, + gnutls_certificate_credentials_t prev, + bool self_cert, bool *changed) +{ + if (creds == NULL || prev == NULL) { + *changed = true; + return KNOT_EOK; + } + + gnutls_x509_crt_t cert = NULL, cert_prev = NULL; + + int ret = creds_cert(creds, &cert); + if (ret != KNOT_EOK) { + goto failed; + } + ret = creds_cert(prev, &cert_prev); + if (ret != KNOT_EOK) { + goto failed; + } + + if (self_cert) { + uint8_t pin[KNOT_TLS_PIN_LEN], pin_prev[KNOT_TLS_PIN_LEN]; + size_t pin_size = sizeof(pin), pin_prev_size = sizeof(pin_prev); + + ret = gnutls_x509_crt_get_key_id(cert, GNUTLS_KEYID_USE_SHA256, + pin, &pin_size); + if (ret != KNOT_EOK) { + goto failed; + } + ret = gnutls_x509_crt_get_key_id(cert_prev, GNUTLS_KEYID_USE_SHA256, + pin_prev, &pin_prev_size); + if (ret != KNOT_EOK) { + goto failed; + } + + *changed = (pin_size != pin_prev_size) || + memcmp(pin, pin_prev, pin_size) != 0; + } else { + *changed = (gnutls_x509_crt_equals(cert, cert_prev) == 0); + } + + ret = KNOT_EOK; +failed: + gnutls_x509_crt_deinit(cert); + gnutls_x509_crt_deinit(cert_prev); + + return ret; +} + +_public_ +int knot_creds_update(struct knot_creds *creds, const char *key_file, const char *cert_file) +{ + if (creds == NULL || key_file == NULL) { + return KNOT_EINVAL; + } + + gnutls_certificate_credentials_t new_creds; + int ret = gnutls_certificate_allocate_credentials(&new_creds); + if (ret != GNUTLS_E_SUCCESS) { + return KNOT_ENOMEM; + } + + if (cert_file != NULL) { + ret = gnutls_certificate_set_x509_key_file(new_creds, + cert_file, key_file, + GNUTLS_X509_FMT_PEM); + } else { + ret = self_signed_cert(new_creds, key_file); + } + if (ret != GNUTLS_E_SUCCESS) { + gnutls_certificate_free_credentials(new_creds); + return KNOT_EFILE; + } + + bool changed = false; + ret = creds_changed(new_creds, ATOMIC_GET(creds->cert_creds), + cert_file == NULL, &changed); + if (ret != KNOT_EOK) { + gnutls_certificate_free_credentials(new_creds); + return ret; + } + + if (changed) { + if (creds->cert_creds_prev != NULL) { + gnutls_certificate_free_credentials(creds->cert_creds_prev); + } + creds->cert_creds_prev = ATOMIC_XCHG(creds->cert_creds, new_creds); + } else { + gnutls_certificate_free_credentials(new_creds); + } + + return KNOT_EOK; +} + +_public_ +int knot_creds_cert(struct knot_creds *creds, struct gnutls_x509_crt_int **cert) +{ + if (creds == NULL || cert == NULL) { + return KNOT_EINVAL; + } + + return creds_cert(ATOMIC_GET(creds->cert_creds), cert); +} + +_public_ +void knot_creds_free(struct knot_creds *creds) +{ + if (creds == NULL) { + return; + } + + if (!creds->peer && creds->cert_creds != NULL) { + gnutls_certificate_free_credentials(creds->cert_creds); + if (creds->cert_creds_prev != NULL) { + gnutls_certificate_free_credentials(creds->cert_creds_prev); + } + } + gnutls_anti_replay_deinit(creds->tls_anti_replay); + if (creds->tls_ticket_key.data != NULL) { + tls_session_ticket_key_free(&creds->tls_ticket_key); + } + free(creds); +} + +_public_ +int knot_tls_session(struct gnutls_session_int **session, + struct knot_creds *creds, + struct gnutls_priority_st *priority, + const char *alpn, + bool early_data, + bool server) +{ + if (session == NULL || creds == NULL || priority == NULL || alpn == NULL) { + return KNOT_EINVAL; + } + + gnutls_init_flags_t flags = GNUTLS_NO_SIGNAL; + if (early_data) { + flags |= GNUTLS_ENABLE_EARLY_DATA; +#ifdef ENABLE_QUIC // Next flags aren't available in older GnuTLS versions. + flags |= GNUTLS_NO_AUTO_SEND_TICKET | GNUTLS_NO_END_OF_EARLY_DATA; +#endif + } + + int ret = gnutls_init(session, (server ? GNUTLS_SERVER : GNUTLS_CLIENT) | flags); + if (ret == GNUTLS_E_SUCCESS) { + gnutls_certificate_send_x509_rdn_sequence(*session, 1); + gnutls_certificate_server_set_request(*session, GNUTLS_CERT_REQUEST); + ret = gnutls_priority_set(*session, priority); + } + if (server && ret == GNUTLS_E_SUCCESS) { + ret = gnutls_session_ticket_enable_server(*session, &creds->tls_ticket_key); + } + if (ret == GNUTLS_E_SUCCESS) { + const gnutls_datum_t alpn_datum = { (void *)&alpn[1], alpn[0] }; + gnutls_alpn_set_protocols(*session, &alpn_datum, 1, GNUTLS_ALPN_MANDATORY); + if (early_data) { + gnutls_record_set_max_early_data_size(*session, 0xffffffffu); + } + if (server) { + gnutls_anti_replay_enable(*session, creds->tls_anti_replay); + } + ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE, + ATOMIC_GET(creds->cert_creds)); + } + if (ret != GNUTLS_E_SUCCESS) { + gnutls_deinit(*session); + *session = NULL; + } + return ret == GNUTLS_E_SUCCESS ? KNOT_EOK : KNOT_ERROR; +} + +_public_ +void knot_tls_pin(struct gnutls_session_int *session, uint8_t *pin, + size_t *pin_size, bool local) +{ + if (session == NULL) { + goto error; + } + + const gnutls_datum_t *data = NULL; + if (local) { + data = gnutls_certificate_get_ours(session); + } else { + unsigned count = 0; + data = gnutls_certificate_get_peers(session, &count); + if (count == 0) { + goto error; + } + } + if (data == NULL) { + goto error; + } + + gnutls_x509_crt_t cert; + int ret = gnutls_x509_crt_init(&cert); + if (ret != GNUTLS_E_SUCCESS) { + goto error; + } + + ret = gnutls_x509_crt_import(cert, data, GNUTLS_X509_FMT_DER); + if (ret != GNUTLS_E_SUCCESS) { + gnutls_x509_crt_deinit(cert); + goto error; + } + + ret = gnutls_x509_crt_get_key_id(cert, GNUTLS_KEYID_USE_SHA256, pin, pin_size); + if (ret != GNUTLS_E_SUCCESS) { + gnutls_x509_crt_deinit(cert); + goto error; + } + + gnutls_x509_crt_deinit(cert); + + return; +error: + if (pin_size != NULL) { + *pin_size = 0; + } +} + +_public_ +int knot_tls_pin_check(struct gnutls_session_int *session, + struct knot_creds *creds) +{ + if (creds->peer_pin_len == 0) { + return KNOT_EOK; + } + + uint8_t pin[KNOT_TLS_PIN_LEN]; + size_t pin_size = sizeof(pin); + knot_tls_pin(session, pin, &pin_size, false); + if (pin_size != creds->peer_pin_len || + const_time_memcmp(pin, creds->peer_pin, pin_size) != 0) { + return KNOT_EBADCERTKEY; + } + + return KNOT_EOK; +} diff --git a/src/libknot/quic/tls_common.h b/src/libknot/quic/tls_common.h new file mode 100644 index 0000000..934f256 --- /dev/null +++ b/src/libknot/quic/tls_common.h @@ -0,0 +1,134 @@ +/* Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +/*! + * \file + * + * \brief Credentials handling common to QUIC and TLS. + * + * \addtogroup quic + * @{ + */ + +#pragma once + +#include <stdbool.h> +#include <stddef.h> +#include <stdint.h> + +#define KNOT_TLS_PIN_LEN 32 +#define KNOT_TLS_PRIORITIES "-VERS-ALL:+VERS-TLS1.3:" \ + "-GROUP-ALL:+GROUP-X25519:+GROUP-SECP256R1:" \ + "+GROUP-SECP384R1:+GROUP-SECP521R1" + +struct gnutls_priority_st; +struct gnutls_session_int; +struct gnutls_x509_crt_int; +struct knot_creds; + +/*! + * \brief Init server TLS key and certificate for DoQ. + * + * \param key_file Key PEM file path/name. + * \param cert_file X509 certificate PEM file path/name (NULL if auto-generated). + * + * \return Initialized creds. + */ +struct knot_creds *knot_creds_init(const char *key_file, const char *cert_file); + +/*! + * \brief Init peer TLS key and certificate for DoQ. + * + * \param local_creds Local credentials if server. + * \param peer_pin Optional peer certificate pin to check. + * \param peer_pin_len Length of the peer pin. Set 0 if not specified. + * + * \return Initialized creds. + */ +struct knot_creds *knot_creds_init_peer(const struct knot_creds *local_creds, + const uint8_t *peer_pin, + uint8_t peer_pin_len); + +/*! + * \brief Load new server TLS key and certificate for DoQ. + * + * \param creds Server credentials where key/cert pair will be updated. + * \param key_file Key PEM file path/name. + * \param cert_file X509 certificate PEM file path/name (NULL if auto-generated). + * + * \return KNOT_E* + */ +int knot_creds_update(struct knot_creds *creds, const char *key_file, const char *cert_file); + +/*! + * \brief Gets the certificate from credentials. + * + * \param creds TLS credentials. + * \param cert Output certificate. + * + * \return KNOT_E* + */ +int knot_creds_cert(struct knot_creds *creds, struct gnutls_x509_crt_int **cert); + +/*! + * \brief Deinit server TLS certificate for DoQ. + */ +void knot_creds_free(struct knot_creds *creds); + +/*! + * \brief Initialize GnuTLS session with credentials, ALPN, etc. + * + * \param session Out: initialized GnuTLS session struct. + * \param creds Certificate credentials. + * \param priority Session priority configuration. + * \param alpn ALPN string, first byte is the string length. + * \param early_data Allow early data. + * \param server Should be server session (otherwise client). + * + * \return KNOT_E* + */ +int knot_tls_session(struct gnutls_session_int **session, + struct knot_creds *creds, + struct gnutls_priority_st *priority, + const char *alpn, + bool early_data, + bool server); + +/*! + * \brief Gets local or remote certificate pin. + * + * \note Zero output pin_size value means no certificate available or error. + * + * \param session TLS connection. + * \param pin Output certificate pin. + * \param pin_size Input size of the storage / output size of the stored pin. + * \param local Local or remote certificate indication. + */ +void knot_tls_pin(struct gnutls_session_int *session, uint8_t *pin, + size_t *pin_size, bool local); + +/*! + * \brief Checks remote certificate pin in the session against credentials. + * + * \param session TLS connection. + * \param creds TLS credentials. + * + * \return KNOT_EOK or KNOT_EBADCERTKEY + */ +int knot_tls_pin_check(struct gnutls_session_int *session, + struct knot_creds *creds); + +/*! @} */ |