Adding upstream version 1.1.0+debian.upstream/1.1.0+debian

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 471 insertions, 0 deletions

diff --git a/src/output/dnssim/connection.c b/src/output/dnssim/connection.c
new file mode 100644
index 0000000..eeb1ce8
--- /dev/null
+++ b/src/output/dnssim/connection.c
@@ -0,0 +1,471 @@
+/*
+ * 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 <string.h>
+
+static core_log_t _log = LOG_T_INIT("output.dnssim");
+
+static bool _conn_is_connecting(_output_dnssim_connection_t* conn)
+{
+    return (conn->state >= _OUTPUT_DNSSIM_CONN_TCP_HANDSHAKE && conn->state <= _OUTPUT_DNSSIM_CONN_ACTIVE);
+}
+
+void _output_dnssim_conn_maybe_free(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn can't be nil");
+    mlassert(conn->client, "conn must belong to a client");
+    if (conn->handle == NULL && conn->handshake_timer == NULL && conn->idle_timer == NULL) {
+        _ll_try_remove(conn->client->conn, conn);
+        if (conn->tls != NULL) {
+            free(conn->tls);
+            conn->tls = NULL;
+        }
+        if (conn->http2 != NULL) {
+            free(conn->http2);
+            conn->http2 = NULL;
+        }
+        free(conn);
+    }
+}
+
+static void _on_handshake_timer_closed(uv_handle_t* handle)
+{
+    _output_dnssim_connection_t* conn = (_output_dnssim_connection_t*)handle->data;
+    mlassert(conn, "conn is nil");
+    mlassert(conn->handshake_timer, "conn must have handshake timer when closing it");
+    free(conn->handshake_timer);
+    conn->handshake_timer = NULL;
+    _output_dnssim_conn_maybe_free(conn);
+}
+
+static void _on_idle_timer_closed(uv_handle_t* handle)
+{
+    _output_dnssim_connection_t* conn = (_output_dnssim_connection_t*)handle->data;
+    mlassert(conn, "conn is nil");
+    mlassert(conn->idle_timer, "conn must have idle timer when closing it");
+    free(conn->idle_timer);
+    conn->is_idle    = false;
+    conn->idle_timer = NULL;
+    _output_dnssim_conn_maybe_free(conn);
+}
+
+void _output_dnssim_conn_close(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn can't be nil");
+    mlassert(conn->stats, "conn must have stats");
+    mlassert(conn->client, "conn must have client");
+    mlassert(conn->client->dnssim, "client must have dnssim");
+
+    output_dnssim_t* self = conn->client->dnssim;
+
+    switch (conn->state) {
+    case _OUTPUT_DNSSIM_CONN_CLOSING:
+    case _OUTPUT_DNSSIM_CONN_CLOSED:
+        return;
+    case _OUTPUT_DNSSIM_CONN_TCP_HANDSHAKE:
+    case _OUTPUT_DNSSIM_CONN_TLS_HANDSHAKE:
+        conn->stats->conn_handshakes_failed++;
+        self->stats_sum->conn_handshakes_failed++;
+        break;
+    case _OUTPUT_DNSSIM_CONN_ACTIVE:
+    case _OUTPUT_DNSSIM_CONN_CONGESTED:
+        self->stats_current->conn_active--;
+        break;
+    case _OUTPUT_DNSSIM_CONN_INITIALIZED:
+    case _OUTPUT_DNSSIM_CONN_CLOSE_REQUESTED:
+        break;
+    default:
+        lfatal("unknown conn state: %d", conn->state);
+    }
+    if (conn->prevent_close) {
+        lassert(conn->state <= _OUTPUT_DNSSIM_CONN_CLOSE_REQUESTED, "conn already closing");
+        conn->state = _OUTPUT_DNSSIM_CONN_CLOSE_REQUESTED;
+        return;
+    }
+    conn->state = _OUTPUT_DNSSIM_CONN_CLOSING;
+
+    if (conn->handshake_timer != NULL) {
+        uv_timer_stop(conn->handshake_timer);
+        uv_close((uv_handle_t*)conn->handshake_timer, _on_handshake_timer_closed);
+    }
+    if (conn->idle_timer != NULL) {
+        conn->is_idle = false;
+        uv_timer_stop(conn->idle_timer);
+        uv_close((uv_handle_t*)conn->idle_timer, _on_idle_timer_closed);
+    }
+
+    switch (_self->transport) {
+    case OUTPUT_DNSSIM_TRANSPORT_TCP:
+        _output_dnssim_tcp_close(conn);
+        break;
+    case OUTPUT_DNSSIM_TRANSPORT_TLS:
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+        _output_dnssim_tls_close(conn);
+#else
+        lfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+        break;
+    case OUTPUT_DNSSIM_TRANSPORT_HTTPS2:
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+        _output_dnssim_https2_close(conn);
+#else
+        lfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+        break;
+    default:
+        lfatal("unsupported transport");
+        break;
+    }
+}
+
+/* Close connection or run idle timer when there are no more outstanding queries. */
+void _output_dnssim_conn_idle(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn can't be nil");
+
+    if (conn->queued == NULL && conn->sent == NULL) {
+        if (conn->idle_timer == NULL)
+            _output_dnssim_conn_close(conn);
+        else if (!conn->is_idle) {
+            conn->is_idle = true;
+            uv_timer_again(conn->idle_timer);
+        }
+    }
+}
+
+static void _send_pending_queries(_output_dnssim_connection_t* conn)
+{
+    _output_dnssim_query_tcp_t* qry;
+    mlassert(conn, "conn is nil");
+    mlassert(conn->client, "conn->client is nil");
+    qry = (_output_dnssim_query_tcp_t*)conn->client->pending;
+
+    while (qry != NULL && conn->state == _OUTPUT_DNSSIM_CONN_ACTIVE) {
+        _output_dnssim_query_tcp_t* next = (_output_dnssim_query_tcp_t*)qry->qry.next;
+        if (qry->qry.state == _OUTPUT_DNSSIM_QUERY_PENDING_WRITE) {
+            switch (qry->qry.transport) {
+            case OUTPUT_DNSSIM_TRANSPORT_TCP:
+                _output_dnssim_tcp_write_query(conn, qry);
+                break;
+            case OUTPUT_DNSSIM_TRANSPORT_TLS:
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+                _output_dnssim_tls_write_query(conn, qry);
+#else
+                mlfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+                break;
+            case OUTPUT_DNSSIM_TRANSPORT_HTTPS2:
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+                _output_dnssim_https2_write_query(conn, qry);
+#else
+                mlfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+                break;
+            default:
+                mlfatal("unsupported protocol");
+                break;
+            }
+        }
+        qry = next;
+    }
+}
+
+int _output_dnssim_handle_pending_queries(_output_dnssim_client_t* client)
+{
+    int ret = 0;
+    mlassert(client, "client is nil");
+
+    if (client->pending == NULL)
+        return ret;
+
+    output_dnssim_t* self = client->dnssim;
+    mlassert(self, "client must belong to dnssim");
+
+    /* Get active connection or find out whether new connection has to be opened. */
+    bool                         is_connecting = false;
+    _output_dnssim_connection_t* conn          = client->conn;
+    while (conn != NULL) {
+        if (conn->state == _OUTPUT_DNSSIM_CONN_ACTIVE)
+            break;
+        else if (_conn_is_connecting(conn))
+            is_connecting = true;
+        conn = conn->next;
+    }
+
+    if (conn != NULL) { /* Send data right away over active connection. */
+        _send_pending_queries(conn);
+    } else if (!is_connecting) { /* No active or connecting connection -> open a new one. */
+        lfatal_oom(conn = calloc(1, sizeof(_output_dnssim_connection_t)));
+        conn->state  = _OUTPUT_DNSSIM_CONN_INITIALIZED;
+        conn->client = client;
+        conn->stats  = self->stats_current;
+        if (_self->transport == OUTPUT_DNSSIM_TRANSPORT_TLS) {
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+            ret = _output_dnssim_tls_init(conn);
+            if (ret < 0) {
+                free(conn);
+                return ret;
+            }
+#else
+            lfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+        } else if (_self->transport == OUTPUT_DNSSIM_TRANSPORT_HTTPS2) {
+#if GNUTLS_VERSION_NUMBER >= DNSSIM_MIN_GNUTLS_VERSION
+            ret = _output_dnssim_https2_init(conn);
+            if (ret < 0) {
+                free(conn);
+                return ret;
+            }
+#else
+            lfatal(DNSSIM_MIN_GNUTLS_ERRORMSG);
+#endif
+        }
+        ret = _output_dnssim_tcp_connect(self, conn);
+        if (ret < 0)
+            return ret;
+        _ll_append(client->conn, conn);
+    } /* Otherwise, pending queries wil be sent after connected callback. */
+
+    return ret;
+}
+
+void _output_dnssim_conn_activate(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn is nil");
+    mlassert(conn->client, "conn must be associated with a client");
+    mlassert(conn->client->dnssim, "client must be associated with dnssim");
+
+    uv_timer_stop(conn->handshake_timer);
+
+    conn->state = _OUTPUT_DNSSIM_CONN_ACTIVE;
+    conn->client->dnssim->stats_current->conn_active++;
+    conn->read_state            = _OUTPUT_DNSSIM_READ_STATE_DNSLEN;
+    conn->dnsbuf_len            = 2;
+    conn->dnsbuf_pos            = 0;
+    conn->dnsbuf_free_after_use = false;
+
+    _send_pending_queries(conn);
+    _output_dnssim_conn_idle(conn);
+}
+
+int _process_dnsmsg(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn can't be nil");
+    mlassert(conn->client, "conn must have client");
+    mlassert(conn->client->dnssim, "client must have dnssim");
+
+    output_dnssim_t* self = conn->client->dnssim;
+
+    core_object_payload_t payload = CORE_OBJECT_PAYLOAD_INIT(NULL);
+    core_object_dns_t     dns_a   = CORE_OBJECT_DNS_INIT(&payload);
+
+    payload.payload = (uint8_t*)conn->dnsbuf_data;
+    payload.len     = conn->dnsbuf_len;
+
+    dns_a.obj_prev = (core_object_t*)&payload;
+    int ret        = core_object_dns_parse_header(&dns_a);
+    if (ret != 0) {
+        lwarning("tcp response malformed");
+        return _ERR_MALFORMED;
+    }
+    ldebug("tcp recv dnsmsg id: %04x", dns_a.id);
+
+    _output_dnssim_query_t* qry;
+
+    if (_self->transport == OUTPUT_DNSSIM_TRANSPORT_HTTPS2) {
+        lassert(conn->http2, "conn must have http2 ctx");
+        lassert(conn->http2->current_qry, "http2 has no current_qry");
+        lassert(conn->http2->current_qry->qry.req, "current_qry has no req");
+        lassert(conn->http2->current_qry->qry.req->dns_q, "req has no dns_q");
+
+        ret = _output_dnssim_answers_request(conn->http2->current_qry->qry.req, &dns_a);
+        switch (ret) {
+        case 0:
+            _output_dnssim_request_answered(conn->http2->current_qry->qry.req, &dns_a);
+            break;
+        case _ERR_MSGID:
+            lwarning("https2 QID mismatch: request=0x%04x, response=0x%04x",
+                conn->http2->current_qry->qry.req->dns_q->id, dns_a.id);
+            break;
+        case _ERR_QUESTION:
+        default:
+            lwarning("https2 response question mismatch");
+            break;
+        }
+    } else {
+        qry = conn->sent;
+        while (qry != NULL) {
+            if (qry->req->dns_q->id == dns_a.id) {
+                ret = _output_dnssim_answers_request(qry->req, &dns_a);
+                if (ret != 0) {
+                    lwarning("response question mismatch");
+                } else {
+                    _output_dnssim_request_answered(qry->req, &dns_a);
+                }
+                break;
+            }
+            qry = qry->next;
+        }
+    }
+
+    return 0;
+}
+
+static int _parse_dnsbuf_data(_output_dnssim_connection_t* conn)
+{
+    mlassert(conn, "conn can't be nil");
+    mlassert(conn->dnsbuf_pos == conn->dnsbuf_len, "attempt to parse incomplete dnsbuf_data");
+    int ret = 0;
+
+    switch (conn->read_state) {
+    case _OUTPUT_DNSSIM_READ_STATE_DNSLEN: {
+        uint16_t* p_dnslen = (uint16_t*)conn->dnsbuf_data;
+        conn->dnsbuf_len   = ntohs(*p_dnslen);
+        if (conn->dnsbuf_len == 0) {
+            mlwarning("invalid dnslen received: 0");
+            conn->dnsbuf_len = 2;
+            conn->read_state = _OUTPUT_DNSSIM_READ_STATE_DNSLEN;
+        } else if (conn->dnsbuf_len < 12) {
+            mldebug("invalid dnslen received: %d", conn->dnsbuf_len);
+            ret = -1;
+        } else {
+            mldebug("dnslen: %d", conn->dnsbuf_len);
+            conn->read_state = _OUTPUT_DNSSIM_READ_STATE_DNSMSG;
+        }
+        break;
+    }
+    case _OUTPUT_DNSSIM_READ_STATE_DNSMSG:
+        ret = _process_dnsmsg(conn);
+        if (ret) {
+            conn->read_state = _OUTPUT_DNSSIM_READ_STATE_INVALID;
+        } else {
+            conn->dnsbuf_len = 2;
+            conn->read_state = _OUTPUT_DNSSIM_READ_STATE_DNSLEN;
+        }
+        break;
+    default:
+        mlfatal("tcp invalid connection read_state");
+        break;
+    }
+
+    conn->dnsbuf_pos = 0;
+    if (conn->dnsbuf_free_after_use) {
+        conn->dnsbuf_free_after_use = false;
+        free(conn->dnsbuf_data);
+    }
+    conn->dnsbuf_data = NULL;
+
+    return ret;
+}
+
+static unsigned int _read_dns_stream_chunk(_output_dnssim_connection_t* conn, size_t len, const char* data)
+{
+    mlassert(conn, "conn can't be nil");
+    mlassert(data, "data can't be nil");
+    mlassert(len > 0, "no data to read");
+    mlassert((conn->read_state == _OUTPUT_DNSSIM_READ_STATE_DNSLEN || conn->read_state == _OUTPUT_DNSSIM_READ_STATE_DNSMSG),
+        "connection has invalid read_state");
+
+    int          ret = 0;
+    unsigned int nread;
+    size_t       expected = conn->dnsbuf_len - conn->dnsbuf_pos;
+    mlassert(expected > 0, "no data expected");
+
+    if (conn->dnsbuf_free_after_use == false && expected > len) {
+        /* Start of partial read. */
+        mlassert(conn->dnsbuf_pos == 0, "conn->dnsbuf_pos must be 0 at start of partial read");
+        mlassert(conn->dnsbuf_len > 0, "conn->dnsbuf_len must be set at start of partial read");
+        mlfatal_oom(conn->dnsbuf_data = malloc(conn->dnsbuf_len * sizeof(char)));
+        conn->dnsbuf_free_after_use = true;
+    }
+
+    if (conn->dnsbuf_free_after_use) { /* Partial read is in progress. */
+        char* dest = conn->dnsbuf_data + conn->dnsbuf_pos;
+        if (expected < len)
+            len = expected;
+        memcpy(dest, data, len);
+        conn->dnsbuf_pos += len;
+        nread = len;
+    } else { /* Complete and clean read. */
+        mlassert(expected <= len, "not enough data to perform complete read");
+        conn->dnsbuf_data = (char*)data;
+        conn->dnsbuf_pos  = conn->dnsbuf_len;
+        nread             = expected;
+    }
+
+    /* If entire dnslen/dnsmsg was read, attempt to parse it. */
+    if (conn->dnsbuf_len == conn->dnsbuf_pos) {
+        ret = _parse_dnsbuf_data(conn);
+        if (ret < 0)
+            return ret;
+    }
+
+    return nread;
+}
+
+void _output_dnssim_read_dns_stream(_output_dnssim_connection_t* conn, size_t len, const char* data)
+{
+    int pos   = 0;
+    int chunk = 0;
+    while (pos < len) {
+        chunk = _read_dns_stream_chunk(conn, len - pos, data + pos);
+        if (chunk < 0) {
+            mlwarning("lost orientation in DNS stream, closing");
+            _output_dnssim_conn_close(conn);
+            break;
+        } else {
+            pos += chunk;
+        }
+    }
+    mlassert((pos == len) || (chunk < 0), "dns stream read invalid, pos != len");
+}
+
+void _output_dnssim_read_dnsmsg(_output_dnssim_connection_t* conn, size_t len, const char* data)
+{
+    mlassert(conn, "conn is nil");
+    mlassert(len > 0, "len is zero");
+    mlassert(data, "no data");
+    mlassert(conn->dnsbuf_pos == 0, "dnsbuf not empty");
+    mlassert(conn->dnsbuf_free_after_use == false, "dnsbuf read in progress");
+
+    /* Read dnsmsg of given length from input data. */
+    conn->dnsbuf_len = len;
+    conn->read_state = _OUTPUT_DNSSIM_READ_STATE_DNSMSG;
+    int nread        = _read_dns_stream_chunk(conn, len, data);
+
+    if (nread != len) {
+        mlwarning("failed to read received dnsmsg");
+        if (conn->dnsbuf_free_after_use)
+            free(conn->dnsbuf_data);
+    }
+
+    /* Clean state afterwards. */
+    conn->read_state            = _OUTPUT_DNSSIM_READ_STATE_DNSLEN;
+    conn->dnsbuf_len            = 2;
+    conn->dnsbuf_pos            = 0;
+    conn->dnsbuf_free_after_use = false;
+}