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Diffstat (limited to '')
-rw-r--r-- | src/output/dnssim/tls.c | 475 |
1 files changed, 0 insertions, 475 deletions
diff --git a/src/output/dnssim/tls.c b/src/output/dnssim/tls.c deleted file mode 100644 index e87ca47..0000000 --- a/src/output/dnssim/tls.c +++ /dev/null @@ -1,475 +0,0 @@ -/* - * Copyright (c) 2020, CZ.NIC, z.s.p.o. - * All rights reserved. - * - * This file is part of dnsjit. - * - * dnsjit 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. - * - * dnsjit 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 dnsjit. If not, see <http://www.gnu.org/licenses/>. - */ - -#include "config.h" - -#include "output/dnssim.h" -#include "output/dnssim/internal.h" -#include "output/dnssim/ll.h" -#include "core/assert.h" - -#include <gnutls/gnutls.h> -#include <string.h> - -#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION - -#ifndef MIN -#define MIN(a, b) (((a) < (b)) ? (a) : (b)) /** Minimum of two numbers **/ -#endif - -static core_log_t _log = LOG_T_INIT("output.dnssim"); - -struct async_write_ctx { - uv_write_t write_req; - _output_dnssim_connection_t* conn; - char buf[]; -}; - -static int _tls_handshake(_output_dnssim_connection_t* conn) -{ - mlassert(conn, "conn is nil"); - mlassert(conn->tls, "conn must have tls context"); - mlassert(conn->client, "conn must belong to a client"); - mlassert(conn->state <= _OUTPUT_DNSSIM_CONN_TLS_HANDSHAKE, "conn in invalid state"); - - /* Set TLS session resumption ticket if available. */ - if (conn->state < _OUTPUT_DNSSIM_CONN_TLS_HANDSHAKE && conn->client->tls_ticket.size != 0) { - gnutls_datum_t* ticket = &conn->client->tls_ticket; - gnutls_session_set_data(conn->tls->session, ticket->data, ticket->size); - } - conn->state = _OUTPUT_DNSSIM_CONN_TLS_HANDSHAKE; - - return gnutls_handshake(conn->tls->session); -} - -void _output_dnssim_tls_process_input_data(_output_dnssim_connection_t* conn) -{ - mlassert(conn, "conn is nil"); - mlassert(conn->client, "conn must have client"); - mlassert(conn->client->dnssim, "client must have dnssim"); - mlassert(conn->tls, "conn must have tls ctx"); - - if (conn->state >= _OUTPUT_DNSSIM_CONN_CLOSING) - return; - - output_dnssim_t* self = conn->client->dnssim; - - /* Ensure TLS handshake is performed before receiving data. - * See https://www.gnutls.org/manual/html_node/TLS-handshake.html */ - while (conn->state <= _OUTPUT_DNSSIM_CONN_TLS_HANDSHAKE) { - int err = _tls_handshake(conn); - mldebug("tls handshake returned: %s", gnutls_strerror(err)); - if (err == GNUTLS_E_SUCCESS) { - if (gnutls_session_is_resumed(conn->tls->session)) - conn->stats->conn_resumed++; - if (_self->transport == OUTPUT_DNSSIM_TRANSPORT_HTTPS2) { - if (_output_dnssim_https2_setup(conn) < 0) { - _output_dnssim_conn_close(conn); - return; - } - } - _output_dnssim_conn_activate(conn); - break; - } else if (err == GNUTLS_E_AGAIN) { - return; /* Wait for more data */ - } else if (err == GNUTLS_E_FATAL_ALERT_RECEIVED) { - gnutls_alert_description_t alert = gnutls_alert_get(conn->tls->session); - mlwarning("gnutls_handshake failed: %s", gnutls_alert_get_name(alert)); - _output_dnssim_conn_close(conn); - return; - } else if (gnutls_error_is_fatal(err)) { - mlwarning("gnutls_handshake failed: %s", gnutls_strerror_name(err)); - _output_dnssim_conn_close(conn); - return; - } - } - - /* See https://gnutls.org/manual/html_node/Data-transfer-and-termination.html#Data-transfer-and-termination */ - while (true) { - /* Connection might have been closed due to an error, don't try to use it. */ - if (conn->state < _OUTPUT_DNSSIM_CONN_ACTIVE || conn->state >= _OUTPUT_DNSSIM_CONN_CLOSING) - return; - - ssize_t count = gnutls_record_recv(conn->tls->session, _self->wire_buf, WIRE_BUF_SIZE); - if (count > 0) { - switch (_self->transport) { - case OUTPUT_DNSSIM_TRANSPORT_TLS: - _output_dnssim_read_dns_stream(conn, count, _self->wire_buf); - break; - case OUTPUT_DNSSIM_TRANSPORT_HTTPS2: - _output_dnssim_https2_process_input_data(conn, count, _self->wire_buf); - break; - default: - lfatal("unsupported transport layer"); - break; - } - } else if (count == GNUTLS_E_AGAIN) { - if (conn->tls->buf_pos == conn->tls->buf_len) { - /* See https://www.gnutls.org/manual/html_node/Asynchronous-operation.html */ - break; /* No more data available in this libuv buffer */ - } - continue; - } else if (count == GNUTLS_E_INTERRUPTED) { - continue; - } else if (count == GNUTLS_E_REHANDSHAKE) { - continue; /* Ignore rehandshake request. */ - } else if (count < 0) { - mlwarning("gnutls_record_recv failed: %s", gnutls_strerror_name(count)); - _output_dnssim_conn_close(conn); - return; - } else if (count == 0) { - break; - } - } - mlassert(conn->tls->buf_len == conn->tls->buf_pos, "tls didn't read the entire buffer"); -} - -static ssize_t _tls_pull(gnutls_transport_ptr_t ptr, void* buf, size_t len) -{ - _output_dnssim_connection_t* conn = (_output_dnssim_connection_t*)ptr; - mlassert(conn != NULL, "conn is null"); - mlassert(conn->tls != NULL, "conn must have tls ctx"); - - ssize_t avail = conn->tls->buf_len - conn->tls->buf_pos; - if (avail <= 0) { - mldebug("tls pull: no more data"); - errno = EAGAIN; - return -1; - } - - ssize_t transfer = MIN(avail, len); - memcpy(buf, conn->tls->buf + conn->tls->buf_pos, transfer); - conn->tls->buf_pos += transfer; - return transfer; -} - -static void _tls_on_write_complete(uv_write_t* req, int status) -{ - mlassert(req->data != NULL, "uv_write req has no data pointer"); - struct async_write_ctx* async_ctx = (struct async_write_ctx*)req->data; - _output_dnssim_connection_t* conn = async_ctx->conn; - mlassert(conn, "conn is nil"); - mlassert(conn->tls, "conn must have tls ctx"); - mlassert(conn->tls->write_queue_size > 0, "invalid write_queue_size: %d", conn->tls->write_queue_size); - conn->tls->write_queue_size -= 1; - free(req->data); - - if (status < 0) - _output_dnssim_conn_close(conn); -} - -static ssize_t _tls_vec_push(gnutls_transport_ptr_t ptr, const giovec_t* iov, int iovcnt) -{ - _output_dnssim_connection_t* conn = (_output_dnssim_connection_t*)ptr; - mlassert(conn != NULL, "conn is null"); - mlassert(conn->tls != NULL, "conn must have tls ctx"); - - if (iovcnt == 0) - return 0; - - /* - * This is a little bit complicated. There are two different writes: - * 1. Immediate, these don't need to own the buffered data and return immediately - * 2. Asynchronous, these need to own the buffers until the write completes - * In order to avoid copying the buffer, an immediate write is tried first if possible. - * If it isn't possible to write the data without queueing, an asynchronous write - * is created (with copied buffered data). - */ - - size_t total_len = 0; - uv_buf_t uv_buf[iovcnt]; - int i; - for (i = 0; i < iovcnt; ++i) { - uv_buf[i].base = iov[i].iov_base; - uv_buf[i].len = iov[i].iov_len; - total_len += iov[i].iov_len; - } - - /* Try to perform the immediate write first to avoid copy */ - int ret = 0; - if (conn->tls->write_queue_size == 0) { - ret = uv_try_write((uv_stream_t*)conn->handle, uv_buf, iovcnt); - /* from libuv documentation - - uv_try_write will return either: - > 0: number of bytes written (can be less than the supplied buffer size). - < 0: negative error code (UV_EAGAIN is returned if no data can be sent immediately). - */ - if (ret == total_len) { - /* All the data were buffered by libuv. - * Return. */ - return ret; - } - - if (ret < 0 && ret != UV_EAGAIN) { - /* uv_try_write() has returned error code other then UV_EAGAIN. - * Return. */ - errno = EIO; - return -1; - } - /* Since we are here expression below is true - * (ret != total_len) && (ret >= 0 || ret == UV_EAGAIN) - * or the same - * (ret != total_len && ret >= 0) || (ret != total_len && ret == UV_EAGAIN) - * i.e. either occurs partial write or UV_EAGAIN. - * Proceed and copy data amount to owned memory and perform async write. - */ - if (ret == UV_EAGAIN) { - /* No data were buffered, so we must buffer all the data. */ - ret = 0; - } - } - - /* Fallback when the queue is full, and it's not possible to do an immediate write */ - char* p = malloc(sizeof(struct async_write_ctx) + total_len - ret); - if (p != NULL) { - struct async_write_ctx* async_ctx = (struct async_write_ctx*)p; - async_ctx->conn = conn; - char* buf = async_ctx->buf; - /* Skip data written in the partial write */ - size_t to_skip = ret; - /* Copy the buffer into owned memory */ - size_t off = 0; - int i; - for (i = 0; i < iovcnt; ++i) { - if (to_skip > 0) { - /* Ignore current buffer if it's all skipped */ - if (to_skip >= uv_buf[i].len) { - to_skip -= uv_buf[i].len; - continue; - } - /* Skip only part of the buffer */ - uv_buf[i].base += to_skip; - uv_buf[i].len -= to_skip; - to_skip = 0; - } - memcpy(buf + off, uv_buf[i].base, uv_buf[i].len); - off += uv_buf[i].len; - } - uv_buf[0].base = buf; - uv_buf[0].len = off; - - /* Create an asynchronous write request */ - uv_write_t* write_req = &async_ctx->write_req; - memset(write_req, 0, sizeof(uv_write_t)); - write_req->data = p; - - /* Perform an asynchronous write with a callback */ - if (uv_write(write_req, (uv_stream_t*)conn->handle, uv_buf, 1, _tls_on_write_complete) == 0) { - ret = total_len; - conn->tls->write_queue_size += 1; - } else { - free(p); - errno = EIO; - ret = -1; - } - } else { - errno = ENOMEM; - ret = -1; - } - - return ret; -} - -int _tls_pull_timeout(gnutls_transport_ptr_t ptr, unsigned int ms) -{ - _output_dnssim_connection_t* conn = (_output_dnssim_connection_t*)ptr; - mlassert(conn != NULL, "conn is null"); - mlassert(conn->tls != NULL, "conn must have tls ctx"); - - ssize_t avail = conn->tls->buf_len - conn->tls->buf_pos; - if (avail <= 0) { - errno = EAGAIN; - return -1; - } - return avail; -} - -int _output_dnssim_tls_init(_output_dnssim_connection_t* conn) -{ - mlassert(conn, "conn is nil"); - mlassert(conn->tls == NULL, "conn already has tls context"); - - int ret; - mlfatal_oom(conn->tls = malloc(sizeof(_output_dnssim_tls_ctx_t))); - conn->tls->buf = NULL; - conn->tls->buf_len = 0; - conn->tls->buf_pos = 0; - conn->tls->write_queue_size = 0; - - ret = gnutls_init(&conn->tls->session, GNUTLS_CLIENT | GNUTLS_NONBLOCK); - if (ret < 0) { - mldebug("failed gnutls_init() (%s)", gnutls_strerror(ret)); - free(conn->tls); - conn->tls = 0; - return ret; - } - - output_dnssim_t* self = conn->client->dnssim; - if (_self->tls_priority == NULL) { - ret = gnutls_set_default_priority(conn->tls->session); - if (ret < 0) { - mldebug("failed gnutls_set_default_priority() (%s)", gnutls_strerror(ret)); - gnutls_deinit(conn->tls->session); - free(conn->tls); - conn->tls = 0; - return ret; - } - } else { - ret = gnutls_priority_set(conn->tls->session, *_self->tls_priority); - if (ret < 0) { - mldebug("failed gnutls_priority_set() (%s)", gnutls_strerror(ret)); - gnutls_deinit(conn->tls->session); - free(conn->tls); - conn->tls = 0; - return ret; - } - } - - ret = gnutls_credentials_set(conn->tls->session, GNUTLS_CRD_CERTIFICATE, _self->tls_cred); - if (ret < 0) { - mldebug("failed gnutls_credentials_set() (%s)", gnutls_strerror(ret)); - gnutls_deinit(conn->tls->session); - free(conn->tls); - conn->tls = 0; - return ret; - } - - gnutls_transport_set_pull_function(conn->tls->session, _tls_pull); - gnutls_transport_set_pull_timeout_function(conn->tls->session, _tls_pull_timeout); - gnutls_transport_set_vec_push_function(conn->tls->session, _tls_vec_push); - gnutls_transport_set_ptr(conn->tls->session, conn); - - return 0; -} - -int _output_dnssim_create_query_tls(output_dnssim_t* self, _output_dnssim_request_t* req) -{ - mlassert_self(); - lassert(req, "req is nil"); - lassert(req->client, "request must have a client associated with it"); - - _output_dnssim_query_tcp_t* qry; - - lfatal_oom(qry = calloc(1, sizeof(_output_dnssim_query_tcp_t))); - - qry->qry.transport = OUTPUT_DNSSIM_TRANSPORT_TLS; - qry->qry.req = req; - qry->qry.state = _OUTPUT_DNSSIM_QUERY_PENDING_WRITE; - req->qry = &qry->qry; // TODO change when adding support for multiple Qs for req - _ll_append(req->client->pending, &qry->qry); - - return _output_dnssim_handle_pending_queries(req->client); -} - -void _output_dnssim_close_query_tls(_output_dnssim_query_tcp_t* qry) -{ - mlassert(qry, "qry can't be null"); - mlassert(qry->qry.req, "query must be part of a request"); - _output_dnssim_request_t* req = qry->qry.req; - mlassert(req->client, "request must belong to a client"); - - _ll_try_remove(req->client->pending, &qry->qry); - if (qry->conn) { - _output_dnssim_connection_t* conn = qry->conn; - _ll_try_remove(conn->sent, &qry->qry); - qry->conn = NULL; - _output_dnssim_conn_idle(conn); - } - - _ll_remove(req->qry, &qry->qry); - free(qry); -} - -void _output_dnssim_tls_close(_output_dnssim_connection_t* conn) -{ - mlassert(conn, "conn can't be nil"); - mlassert(conn->tls, "conn must have tls ctx"); - mlassert(conn->client, "conn must belong to a client"); - - /* Try and get a TLS session ticket for potential resumption. */ - int ret; - if (gnutls_session_get_flags(conn->tls->session) & GNUTLS_SFLAGS_SESSION_TICKET) { - if (conn->client->tls_ticket.size != 0) { - gnutls_free(conn->client->tls_ticket.data); - } - ret = gnutls_session_get_data2(conn->tls->session, &conn->client->tls_ticket); - if (ret < 0) { - mldebug("gnutls_session_get_data2 failed: %s", gnutls_strerror(ret)); - conn->client->tls_ticket.size = 0; - } - } - - gnutls_deinit(conn->tls->session); - _output_dnssim_tcp_close(conn); -} - -void _output_dnssim_tls_write_query(_output_dnssim_connection_t* conn, _output_dnssim_query_tcp_t* qry) -{ - mlassert(qry, "qry can't be null"); - mlassert(qry->qry.state == _OUTPUT_DNSSIM_QUERY_PENDING_WRITE, "qry must be pending write"); - mlassert(qry->qry.req, "req can't be null"); - mlassert(qry->qry.req->dns_q, "dns_q can't be null"); - mlassert(qry->qry.req->dns_q->obj_prev, "payload can't be null"); - mlassert(conn, "conn can't be null"); - mlassert(conn->state == _OUTPUT_DNSSIM_CONN_ACTIVE, "connection state != ACTIVE"); - mlassert(conn->tls, "conn must have tls ctx"); - mlassert(conn->client, "conn must be associated with client"); - mlassert(conn->client->pending, "conn has no pending queries"); - - core_object_payload_t* payload = (core_object_payload_t*)qry->qry.req->dns_q->obj_prev; - uint16_t len = htons(payload->len); - - gnutls_record_cork(conn->tls->session); - ssize_t count = 0; - if ((count = gnutls_record_send(conn->tls->session, &len, sizeof(len)) < 0) || (count = gnutls_record_send(conn->tls->session, payload->payload, payload->len) < 0)) { - mlwarning("gnutls_record_send failed: %s", gnutls_strerror_name(count)); - _output_dnssim_conn_close(conn); - return; - } - - const ssize_t submitted = sizeof(len) + payload->len; - - int ret = gnutls_record_uncork(conn->tls->session, GNUTLS_RECORD_WAIT); - if (gnutls_error_is_fatal(ret)) { - mlinfo("gnutls_record_uncorck failed: %s", gnutls_strerror_name(ret)); - _output_dnssim_conn_close(conn); - return; - } - - if (ret != submitted) { - mlwarning("gnutls_record_uncork didn't send all data"); - _output_dnssim_conn_close(conn); - return; - } - - qry->conn = conn; - _ll_remove(conn->client->pending, &qry->qry); - _ll_append(conn->sent, &qry->qry); - - /* Stop idle timer, since there are queries to answer now. */ - if (conn->idle_timer != NULL) { - conn->is_idle = false; - uv_timer_stop(conn->idle_timer); - } - - qry->qry.state = _OUTPUT_DNSSIM_QUERY_SENT; -} - -#endif |