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-rw-r--r--src/net_doh.c1017
1 files changed, 1017 insertions, 0 deletions
diff --git a/src/net_doh.c b/src/net_doh.c
new file mode 100644
index 0000000..0689fc6
--- /dev/null
+++ b/src/net_doh.c
@@ -0,0 +1,1017 @@
+/*
+ * Copyright 2019-2021 OARC, Inc.
+ * Copyright 2017-2018 Akamai Technologies
+ * Copyright 2006-2016 Nominum, Inc.
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * Based on HTTP/2 module in DNS shotgun by Tomáš Křížek (CZ.NIC)
+ * https://gitlab.nic.cz/knot/shotgun/-/blob/master/replay/dnssim/src/output/dnssim/https2.c
+ *
+ * Initial PoC implementation by Atanas Argirov (PeeriX)
+ * https://github.com/m0rcq
+ */
+
+#include "config.h"
+
+#include "net.h"
+#include "edns.h"
+#include "parse_uri.h"
+#include "log.h"
+#include "strerror.h"
+#include "util.h"
+#include "os.h"
+#include "opt.h"
+
+#include <errno.h>
+#include <assert.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <openssl/err.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <ck_pr.h>
+#include <nghttp2/nghttp2.h>
+#include <openssl/bio.h>
+#include <openssl/evp.h>
+
+#define DNS_GET_REQUEST_VAR "?dns="
+#define DNS_MSG_MAX_SIZE 65535
+
+static SSL_CTX* ssl_ctx = 0;
+static struct URI doh_uri;
+enum perf_doh_method {
+ doh_method_get,
+ doh_method_post
+};
+static enum perf_doh_method doh_method = doh_method_get;
+static size_t doh_max_concurr = 100;
+
+#define self ((struct perf__doh_socket*)sock)
+
+#define MAKE_NV(NAME, VALUE) \
+ { \
+ (uint8_t*)NAME, (uint8_t*)VALUE, sizeof(NAME) - 1, sizeof(VALUE) - 1, \
+ NGHTTP2_NV_FLAG_NONE \
+ }
+
+#define MAKE_NV_LEN(NAME, VALUE, VALUELEN) \
+ { \
+ (uint8_t*)NAME, (uint8_t*)VALUE, sizeof(NAME) - 1, VALUELEN, \
+ NGHTTP2_NV_FLAG_NONE \
+ }
+
+typedef struct {
+ uint8_t *buf, *bufp;
+ size_t len, buf_len;
+} http2_data_provider_t;
+
+typedef struct {
+ nghttp2_session* session;
+ http2_data_provider_t payload;
+ bool settings_sent;
+ char dnsmsg[DNS_MSG_MAX_SIZE];
+ size_t dnsmsg_at;
+ bool dnsmsg_completed;
+} http2_session_t;
+
+struct _doh_stats {
+ size_t code[500];
+ size_t unknown_code;
+};
+
+struct perf__doh_socket {
+ struct perf_net_socket base;
+
+ pthread_mutex_t lock;
+ SSL* ssl;
+
+ bool is_ready, is_conn_ready, is_ssl_ready, is_sending, is_post_sending;
+ // bool have_more; TODO
+ bool do_reconnect;
+
+ perf_sockaddr_t server, local;
+ size_t bufsize;
+
+ uint16_t qid;
+
+ uint64_t conn_ts;
+ perf_socket_event_t conn_event, conning_event;
+
+ http2_session_t http2; // http2 session data
+ int http2_code;
+ bool http2_is_dns;
+
+ struct _doh_stats stats;
+};
+
+static pthread_mutex_t _nghttp2_lock = PTHREAD_MUTEX_INITIALIZER;
+static nghttp2_session_callbacks* _nghttp2_callbacks = 0;
+static nghttp2_option* _nghttp2_option = 0;
+
+void perf_net_doh_parse_uri(const char* uri)
+{
+ if (parse_uri(&doh_uri, uri)) {
+ perf_log_warning("invalid DNS-over-HTTPS URI");
+ perf_opt_usage();
+ exit(1);
+ }
+}
+
+void perf_net_doh_parse_method(const char* method)
+{
+ if (!strcmp(method, "GET")) {
+ doh_method = doh_method_get;
+ return;
+ } else if (!strcmp(method, "POST")) {
+ doh_method = doh_method_post;
+ return;
+ }
+
+ perf_log_warning("invalid DNS-over-HTTPS method");
+ perf_opt_usage();
+ exit(1);
+}
+
+void perf_net_doh_set_max_concurrent_streams(size_t max_concurr)
+{
+ doh_max_concurr = max_concurr;
+}
+
+static void perf__doh_connect(struct perf_net_socket* sock)
+{
+ int ret;
+
+ nghttp2_session_del(self->http2.session);
+ ret = nghttp2_session_client_new2(&self->http2.session, _nghttp2_callbacks, sock, _nghttp2_option);
+ if (ret < 0) {
+ perf_log_fatal("Failed to initialize http2 session: %s", nghttp2_strerror(ret));
+ }
+
+ int fd = socket(self->server.sa.sa.sa_family, SOCK_STREAM, 0);
+ if (fd == -1) {
+ char __s[256];
+ perf_log_fatal("socket: %s", perf_strerror_r(errno, __s, sizeof(__s)));
+ }
+ ck_pr_store_int(&sock->fd, fd);
+
+ if (self->ssl) {
+ SSL_free(self->ssl);
+ }
+ if (!(self->ssl = SSL_new(ssl_ctx))) {
+ perf_log_fatal("SSL_new(): %s", ERR_error_string(ERR_get_error(), 0));
+ }
+ if (!(ret = SSL_set_fd(self->ssl, sock->fd))) {
+ perf_log_fatal("SSL_set_fd(): %s", ERR_error_string(SSL_get_error(self->ssl, ret), 0));
+ }
+
+ if (self->server.sa.sa.sa_family == AF_INET6) {
+ int on = 1;
+
+ if (setsockopt(sock->fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1) {
+ perf_log_warning("setsockopt(IPV6_V6ONLY) failed");
+ }
+ }
+
+ if (bind(sock->fd, &self->local.sa.sa, self->local.length) == -1) {
+ char __s[256];
+ perf_log_fatal("bind: %s", perf_strerror_r(errno, __s, sizeof(__s)));
+ }
+
+ if (self->bufsize > 0) {
+ ret = setsockopt(sock->fd, SOL_SOCKET, SO_RCVBUF,
+ &self->bufsize, sizeof(self->bufsize));
+ if (ret < 0)
+ perf_log_warning("setsockbuf(SO_RCVBUF) failed");
+
+ ret = setsockopt(sock->fd, SOL_SOCKET, SO_SNDBUF,
+ &self->bufsize, sizeof(self->bufsize));
+ if (ret < 0)
+ perf_log_warning("setsockbuf(SO_SNDBUF) failed");
+ }
+
+ int flags = fcntl(sock->fd, F_GETFL, 0);
+ if (flags < 0)
+ perf_log_fatal("fcntl(F_GETFL)");
+ ret = fcntl(sock->fd, F_SETFL, flags | O_NONBLOCK);
+ if (ret < 0)
+ perf_log_fatal("fcntl(F_SETFL)");
+
+ self->conn_ts = perf_get_time();
+ if (sock->event) {
+ sock->event(sock, self->conning_event, self->conn_ts);
+ self->conning_event = perf_socket_event_reconnecting;
+ }
+ if (connect(sock->fd, &self->server.sa.sa, self->server.length)) {
+ if (errno == EINPROGRESS) {
+ return;
+ } else {
+ char __s[256];
+ perf_log_fatal("connect() failed: %s", perf_strerror_r(errno, __s, sizeof(__s)));
+ }
+ }
+
+ self->is_conn_ready = true;
+}
+
+static void perf__doh_reconnect(struct perf_net_socket* sock)
+{
+ close(sock->fd);
+ // self->have_more = false; TODO
+
+ self->http2.settings_sent = false;
+ self->is_ready = false;
+ self->is_conn_ready = false;
+ self->is_ssl_ready = false;
+ self->is_sending = false;
+ self->is_post_sending = false;
+
+ self->http2.dnsmsg_at = 0;
+ self->http2.dnsmsg_completed = false;
+ self->http2_code = 0;
+ self->http2_is_dns = false;
+
+ perf__doh_connect(sock);
+}
+
+// static ssize_t _recv_callback(nghttp2_session *session, uint8_t *buf, size_t length, int flags, void *sock)
+// {
+// if (self->http2.dnsmsg_completed) {
+// return NGHTTP2_ERR_WOULDBLOCK;
+// }
+//
+// ssize_t n = SSL_read(self->ssl, buf, length);
+// if (!n) {
+// perf__doh_reconnect(sock);
+// return NGHTTP2_ERR_WOULDBLOCK;
+// }
+// if (n < 0) {
+// int err = SSL_get_error(self->ssl, n);
+// switch (err) {
+// case SSL_ERROR_WANT_READ:
+// return NGHTTP2_ERR_WOULDBLOCK;
+// case SSL_ERROR_SYSCALL:
+// switch (errno) {
+// case ECONNREFUSED:
+// case ECONNRESET:
+// case ENOTCONN:
+// perf__doh_reconnect(sock);
+// return NGHTTP2_ERR_WOULDBLOCK;
+// default:
+// break;
+// }
+// break;
+// default:
+// break;
+// }
+// return NGHTTP2_ERR_CALLBACK_FAILURE;
+// }
+// return n;
+// }
+
+static ssize_t perf__doh_recv(struct perf_net_socket* sock, void* buf, size_t len, int flags)
+{
+ // read TLS data here instead of nghttp2_recv_callback
+ PERF_LOCK(&self->lock);
+ if (!self->is_ready) {
+ PERF_UNLOCK(&self->lock);
+ errno = EAGAIN;
+ return -1;
+ }
+
+ uint8_t recvbuf[TCP_RECV_BUF_SIZE];
+ ssize_t n = SSL_read(self->ssl, recvbuf, TCP_RECV_BUF_SIZE);
+ if (!n) {
+ perf__doh_reconnect(sock);
+ PERF_UNLOCK(&self->lock);
+ errno = EAGAIN;
+ return -1;
+ }
+ if (n < 0) {
+ int err = SSL_get_error(self->ssl, n);
+ switch (err) {
+ case SSL_ERROR_WANT_READ:
+ errno = EAGAIN;
+ break;
+ case SSL_ERROR_SYSCALL:
+ switch (errno) {
+ case ECONNREFUSED:
+ case ECONNRESET:
+ case ENOTCONN:
+ perf__doh_reconnect(sock);
+ errno = EAGAIN;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ errno = EBADF;
+ break;
+ }
+ PERF_UNLOCK(&self->lock);
+ return -1;
+ }
+
+ // this will be processed by nghttp2 callbacks
+ int ret = nghttp2_session_mem_recv(self->http2.session, recvbuf, n);
+ if (ret < 0) {
+ perf_log_warning("nghttp2_session_mem_recv failed: %s", nghttp2_strerror(ret));
+ PERF_UNLOCK(&self->lock);
+ return -1;
+ }
+ // TODO: handle partial mem_recv
+ if (ret != n) {
+ perf_log_fatal("perf__doh_recv() mem_recv did not take all");
+ }
+
+ // TODO: is this faster then mem_recv?
+ // int ret = nghttp2_session_recv(self->http2.session);
+ // if (ret < 0) {
+ // perf_log_warning("nghttp2_session_recv failed: %s", nghttp2_strerror(ret));
+ // PERF_UNLOCK(&self->lock);
+ // return -1;
+ // }
+
+ if (self->http2.dnsmsg_completed) {
+ if (self->http2_code > 99 && self->http2_code < 600) {
+ self->stats.code[self->http2_code - 100]++;
+ } else {
+ self->stats.unknown_code++;
+ }
+ if (!self->http2_is_dns) {
+ // TODO: store non-dns for stats
+ self->http2.dnsmsg_completed = false;
+ self->http2.dnsmsg_at = 0;
+ self->http2_code = 0;
+ self->http2_is_dns = false;
+ PERF_UNLOCK(&self->lock);
+ errno = EAGAIN;
+ return -1;
+ }
+ if (self->http2_code < 200 || self->http2_code > 299) {
+ // TODO: store return code for stats
+ self->http2.dnsmsg_completed = false;
+ self->http2.dnsmsg_at = 0;
+ self->http2_code = 0;
+ PERF_UNLOCK(&self->lock);
+ errno = EAGAIN;
+ return -1;
+ }
+ if (self->http2.dnsmsg_at < len) {
+ len = self->http2.dnsmsg_at;
+ }
+ memcpy(buf, self->http2.dnsmsg, len);
+ self->http2.dnsmsg_completed = false;
+ self->http2.dnsmsg_at = 0;
+
+ // self->have_more = false; TODO
+ PERF_UNLOCK(&self->lock);
+ return len;
+ }
+
+ // self->have_more = true; TODO
+ PERF_UNLOCK(&self->lock);
+ errno = EAGAIN;
+ return -1;
+}
+
+static void _submit_dns_query_get(struct perf_net_socket* sock, const void* buf, size_t len)
+{
+ const size_t path_len = doh_uri.pathlen
+ + sizeof(DNS_GET_REQUEST_VAR) - 1
+ + (4 * ((len + 2) / 3)) + 1;
+ char full_path[path_len];
+ char* p = &full_path[0];
+
+ memcpy(p, doh_uri.path, doh_uri.pathlen);
+ p += doh_uri.pathlen;
+
+ memcpy(p, DNS_GET_REQUEST_VAR, sizeof(DNS_GET_REQUEST_VAR) - 1);
+ p += sizeof(DNS_GET_REQUEST_VAR) - 1;
+
+ EVP_EncodeBlock((unsigned char*)p, buf, len);
+ // RFC8484 requires base64url (RFC4648)
+ // and Padding characters (=) for base64url MUST NOT be included.
+ // base64url alphabet is the same as base64 except + is - and / is _
+ while (*p) {
+ switch (*p) {
+ case '+':
+ *p++ = '-';
+ break;
+ case '/':
+ *p++ = '_';
+ break;
+ case '=':
+ *p = 0;
+ break;
+ default:
+ p++;
+ }
+ }
+
+ const nghttp2_nv hdrs[] = {
+ MAKE_NV(":method", "GET"),
+ MAKE_NV(":scheme", "https"),
+ MAKE_NV_LEN(":authority", doh_uri.hostport, doh_uri.hostportlen),
+ MAKE_NV_LEN(":path", full_path, p - full_path),
+ MAKE_NV("accept", "application/dns-message"),
+ MAKE_NV("user-agent", "dnsperf/" PACKAGE_VERSION " (nghttp2/" NGHTTP2_VERSION ")")
+ };
+
+ int32_t stream_id = nghttp2_submit_request(self->http2.session,
+ NULL,
+ hdrs,
+ sizeof(hdrs) / sizeof(hdrs[0]),
+ NULL,
+ sock);
+ if (stream_id < 0) {
+ perf_log_fatal("Failed to submit HTTP2 request: %s", nghttp2_strerror(stream_id));
+ }
+}
+
+static ssize_t _payload_read_cb(nghttp2_session* session,
+ int32_t stream_id, uint8_t* buf,
+ size_t length, uint32_t* data_flags,
+ nghttp2_data_source* source,
+ void* sock)
+{
+ http2_data_provider_t* payload = source->ptr;
+
+ ssize_t payload_size = length < payload->len ? length : payload->len;
+
+ memcpy(buf, payload->bufp, payload_size);
+ payload->bufp += payload_size;
+ payload->len -= payload_size;
+ // check for EOF
+ if (payload->len == 0) {
+ *data_flags |= NGHTTP2_DATA_FLAG_EOF;
+ self->is_post_sending = false;
+ }
+
+ return payload_size;
+}
+
+static void _submit_dns_query_post(struct perf_net_socket* sock, const void* buf, size_t len)
+{
+ // POST requires DATA flow-controlled payload that local endpoint
+ // can send across without issuing WINDOW_UPDATE
+ // we need to check for this and bounce back the request if the
+ // payload > remote window size
+ // TODO: are below needed? can they be checked on connect?
+ // int remote_window_size = nghttp2_session_get_remote_window_size(self->http2.session);
+ // if (remote_window_size < 0) {
+ // perf_log_fatal("failed to get http2 session remote window size");
+ // }
+ // if (len > remote_window_size) {
+ // perf_log_fatal("remote window size is too small for POST payload");
+ // }
+
+ // compose content-length
+ char payload_size[20];
+ int payload_size_len = snprintf(payload_size, sizeof(payload_size), "%zu", len);
+ // TODO: check snprintf()
+
+ const nghttp2_nv hdrs[] = {
+ MAKE_NV(":method", "POST"),
+ MAKE_NV(":scheme", "https"),
+ MAKE_NV_LEN(":authority", doh_uri.hostport, doh_uri.hostportlen),
+ MAKE_NV_LEN(":path", doh_uri.path, doh_uri.pathlen),
+ MAKE_NV("accept", "application/dns-message"),
+ MAKE_NV("content-type", "application/dns-message"),
+ MAKE_NV_LEN("content-length", payload_size, payload_size_len),
+ MAKE_NV("user-agent", "dnsperf/" PACKAGE_VERSION " (nghttp2/" NGHTTP2_VERSION ")")
+ };
+
+ if (len > self->http2.payload.buf_len) {
+ self->http2.payload.buf_len = ((len / MAX_EDNS_PACKET) + 1) * MAX_EDNS_PACKET;
+ if (!(self->http2.payload.buf = realloc(self->http2.payload.buf, self->http2.payload.buf_len))) {
+ perf_log_fatal("perf_net_doh: out of memory");
+ }
+ }
+ if (self && self->http2.payload.buf && buf) { // fix clang scan-build
+ memcpy(self->http2.payload.buf, buf, len);
+ } else {
+ perf_log_fatal("_submit_dns_query_post(): payload.buf is null");
+ }
+ self->http2.payload.bufp = self->http2.payload.buf;
+ self->http2.payload.len = len;
+ self->is_post_sending = true;
+
+ // we need data provider to pass to submit()
+
+ nghttp2_data_provider data_provider = {
+ .source.ptr = &self->http2.payload,
+ .read_callback = _payload_read_cb
+ };
+ int32_t stream_id = nghttp2_submit_request(self->http2.session,
+ NULL,
+ hdrs,
+ sizeof(hdrs) / sizeof(hdrs[0]),
+ &data_provider,
+ sock);
+ if (stream_id < 0) {
+ perf_log_fatal("Failed to submit HTTP2 request: %s", nghttp2_strerror(stream_id));
+ }
+}
+
+static ssize_t perf__doh_sendto(struct perf_net_socket* sock, uint16_t qid, const void* buf, size_t len, int flags, const struct sockaddr* dest_addr, socklen_t addrlen)
+{
+ PERF_LOCK(&self->lock);
+
+ if (!self->is_ready) {
+ // TODO: query will be lost here
+ PERF_UNLOCK(&self->lock);
+ errno = EINPROGRESS;
+ return -1;
+ }
+
+ if (self->is_sending) {
+ perf_log_fatal("called when sending");
+ }
+
+ self->qid = qid;
+
+ switch (doh_method) {
+ case doh_method_get:
+ _submit_dns_query_get(sock, buf, len);
+ break;
+ case doh_method_post:
+ _submit_dns_query_post(sock, buf, len);
+ break;
+ }
+
+ int ret = nghttp2_session_send(self->http2.session);
+ if (ret < 0) {
+ // TODO: handle error better, reconnect when needed
+ perf_log_warning("nghttp2_session_send failed: %s", nghttp2_strerror(ret));
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ errno = EINPROGRESS;
+ return -1;
+ }
+
+ if (self->is_post_sending || nghttp2_session_get_outbound_queue_size(self->http2.session) > 0 || nghttp2_session_want_write(self->http2.session)) {
+ self->is_sending = true;
+ PERF_UNLOCK(&self->lock);
+ errno = EINPROGRESS;
+ return -1;
+ }
+ PERF_UNLOCK(&self->lock);
+
+ return len;
+}
+
+static int perf__doh_close(struct perf_net_socket* sock)
+{
+ // TODO
+ return close(sock->fd);
+}
+
+static int perf__doh_sockeq(struct perf_net_socket* sock_a, struct perf_net_socket* sock_b)
+{
+ return sock_a->fd == sock_b->fd;
+}
+
+static int perf__doh_sockready(struct perf_net_socket* sock, int pipe_fd, int64_t timeout)
+{
+ PERF_LOCK(&self->lock);
+
+ if (self->do_reconnect) {
+ perf__doh_reconnect(sock);
+ self->do_reconnect = false;
+ }
+
+ if (self->is_ready) {
+ // do nghttp2 I/O send to flush outstanding frames
+ int ret = nghttp2_session_send(self->http2.session);
+ if (ret != 0) {
+ // TODO: handle error better, reconnect when needed
+ perf_log_warning("nghttp2_session_send failed: %s", nghttp2_strerror(ret));
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+
+ bool sent = false;
+ if (self->is_sending) {
+ if (self->is_post_sending || nghttp2_session_get_outbound_queue_size(self->http2.session) > 0 || nghttp2_session_want_write(self->http2.session)) {
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ self->is_sending = false;
+ sent = true;
+ }
+ PERF_UNLOCK(&self->lock);
+ if (sent && sock->sent) {
+ sock->sent(sock, self->qid);
+ }
+ return 1;
+ }
+
+ if (!self->is_conn_ready) {
+ switch (perf_os_waituntilanywritable(&sock, 1, pipe_fd, timeout)) {
+ case PERF_R_TIMEDOUT:
+ PERF_UNLOCK(&self->lock);
+ return -1;
+ case PERF_R_SUCCESS: {
+ int error = 0;
+ socklen_t len = (socklen_t)sizeof(error);
+
+ getsockopt(sock->fd, SOL_SOCKET, SO_ERROR, (void*)&error, &len);
+ if (error != 0) {
+ if (error == EINPROGRESS
+#if EWOULDBLOCK != EAGAIN
+ || error == EWOULDBLOCK
+#endif
+ || error == EAGAIN) {
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ // unrecoverable error, reconnect
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ break;
+ }
+ default:
+ PERF_UNLOCK(&self->lock);
+ return -1;
+ }
+ self->is_conn_ready = true;
+ }
+
+ if (!self->is_ssl_ready) {
+ int ret = SSL_connect(self->ssl);
+ if (!ret) {
+ // unrecoverable error, reconnect
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ if (ret < 0) {
+ switch (SSL_get_error(self->ssl, ret)) {
+ case SSL_ERROR_WANT_READ:
+ case SSL_ERROR_WANT_WRITE:
+ break;
+ default:
+ // unrecoverable error, reconnect
+ self->do_reconnect = true;
+ }
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+
+ const uint8_t* alpn = 0;
+ uint32_t alpn_len = 0;
+#ifndef OPENSSL_NO_NEXTPROTONEG
+ SSL_get0_next_proto_negotiated(self->ssl, &alpn, &alpn_len);
+#endif /* !OPENSSL_NO_NEXTPROTONEG */
+#if OPENSSL_VERSION_NUMBER >= 0x10002000L
+ if (!alpn) {
+ SSL_get0_alpn_selected(self->ssl, &alpn, &alpn_len);
+ }
+#endif /* OPENSSL_VERSION_NUMBER >= 0x10002000L */
+#if defined(OPENSSL_NO_NEXTPROTONEG) && OPENSSL_VERSION_NUMBER < 0x10002000L
+#error "OpenSSL has no support for getting alpn"
+#endif
+ if (!alpn || alpn_len != 2 || memcmp("h2", alpn, 2) != 0) {
+ perf_log_warning("Unable to get ALPN or not \"h2\", reconnecting");
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ self->is_ssl_ready = true;
+ }
+
+ if (!self->http2.settings_sent) {
+ // send settings
+ // TODO: does sending settings need session_send()?
+ nghttp2_settings_entry iv[] = {
+ { NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, doh_max_concurr },
+ { NGHTTP2_SETTINGS_ENABLE_PUSH, 0 },
+ { NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE, 65535 }
+ };
+ int ret = nghttp2_submit_settings(self->http2.session, NGHTTP2_FLAG_NONE, iv,
+ sizeof(iv) / sizeof(*iv));
+ if (ret != 0) {
+ perf_log_warning("Could not submit https2 SETTINGS: %s", nghttp2_strerror(ret));
+ self->do_reconnect = true;
+ PERF_UNLOCK(&self->lock);
+ return 0;
+ }
+ self->http2.settings_sent = true;
+ }
+
+ self->is_ready = true;
+ PERF_UNLOCK(&self->lock);
+
+ if (sock->event) {
+ sock->event(sock, self->conn_event, perf_get_time() - self->conn_ts);
+ self->conn_event = perf_socket_event_reconnected;
+ }
+
+ return 1;
+}
+
+static bool perf__doh_have_more(struct perf_net_socket* sock)
+{
+ // return self->have_more; TODO
+ return false;
+}
+
+/* nghttp2 callbacks */
+
+static ssize_t _http2_send_cb(nghttp2_session* session,
+ const uint8_t* data,
+ size_t length,
+ int flags,
+ void* sock)
+{
+ // TODO: remove once non-experimental
+ if (!PERF_TRYLOCK(&self->lock)) {
+ perf_log_fatal("_http2_send_cb called without lock");
+ }
+
+ if (!self->is_ready) {
+ return NGHTTP2_ERR_CALLBACK_FAILURE;
+ }
+
+ ssize_t n = SSL_write(self->ssl, data, length);
+ if (n < 1) {
+ switch (SSL_get_error(self->ssl, n)) {
+ case SSL_ERROR_SYSCALL:
+ switch (errno) {
+ case ECONNREFUSED:
+ case ECONNRESET:
+ case ENOTCONN:
+ case EPIPE:
+ perf__doh_reconnect(sock);
+ return NGHTTP2_ERR_CALLBACK_FAILURE;
+ default:
+ break;
+ }
+ break;
+ case SSL_ERROR_WANT_READ:
+ case SSL_ERROR_WANT_WRITE:
+ return NGHTTP2_ERR_WOULDBLOCK;
+ default:
+ break;
+ }
+ perf_log_warning("SSL_write(): %s", ERR_error_string(SSL_get_error(self->ssl, n), 0));
+ return NGHTTP2_ERR_CALLBACK_FAILURE;
+ }
+
+ return n;
+}
+
+static int _http2_frame_recv_cb(nghttp2_session* session, const nghttp2_frame* frame, void* sock)
+{
+ // TODO: remove once non-experimental
+ if (!PERF_TRYLOCK(&self->lock)) {
+ perf_log_fatal("_http2_frame_recv_cb called without lock");
+ }
+
+ switch (frame->hd.type) {
+ case NGHTTP2_DATA:
+ // we are interested in DATA frame which will carry the DNS response
+ // NGHTTP2_FLAG_END_STREAM indicates that we have the data in full
+ if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
+ // TODO: what's the point of below code? if dnsmsg_at > max size then it will already done a buffer overflow
+ // if (self->http2.dnsmsg_at > DNS_MSG_MAX_SIZE) {
+ // perf_log_warning("DNS response > DNS message maximum size");
+ // return NGHTTP2_ERR_CALLBACK_FAILURE;
+ // }
+
+ // TODO: need to be able to receive multiple responses at the same time
+ if (self->http2.dnsmsg_completed) {
+ perf_log_fatal("_http2_frame_recv_cb: frame received when already having a dns msg");
+ }
+
+ self->http2.dnsmsg_completed = true;
+ // self->have_more = false; TODO
+ }
+ break;
+ case NGHTTP2_RST_STREAM:
+ case NGHTTP2_GOAWAY:
+ perf__doh_reconnect(sock);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int _http2_on_header_callback(nghttp2_session* session, const nghttp2_frame* frame, const uint8_t* name, size_t namelen, const uint8_t* value, size_t valuelen, uint8_t flags, void* sock)
+{
+ switch (frame->hd.type) {
+ case NGHTTP2_HEADERS: {
+ if (!value) {
+ return 0;
+ }
+ if (!strncasecmp(":status:", (const char*)name, namelen)) {
+ self->http2_code = atoi((const char*)value);
+ } else if (!strncasecmp("content-type:", (const char*)name, namelen)) {
+ if (!strncasecmp("application/dns-message", (const char*)value, valuelen)) {
+ self->http2_is_dns = true;
+ }
+ }
+ break;
+ }
+ default:
+ break;
+ }
+ return 0;
+}
+
+static int _http2_data_chunk_recv_cb(nghttp2_session* session,
+ uint8_t flags,
+ int32_t stream_id,
+ const uint8_t* data,
+ size_t len, void* sock)
+{
+ // TODO: remove once non-experimental
+ if (!PERF_TRYLOCK(&self->lock)) {
+ perf_log_fatal("_http2_data_chunk_recv_cb called without lock");
+ }
+
+ if (self->http2.dnsmsg_completed) {
+ perf_log_fatal("_http2_data_chunk_recv_cb: chunk received when already having a dns msg");
+ }
+
+ // TODO: point of nghttp2_session_get_stream_user_data() code?
+ // if (nghttp2_session_get_stream_user_data(session, stream_id)) {
+ if (self->http2.dnsmsg_at + len > DNS_MSG_MAX_SIZE) {
+ perf_log_warning("http2 chunk data exceeds DNS message max size");
+ return NGHTTP2_ERR_CALLBACK_FAILURE;
+ }
+ memcpy(self->http2.dnsmsg + self->http2.dnsmsg_at, data, len);
+ self->http2.dnsmsg_at += len;
+ // }
+
+ return 0;
+}
+
+#ifndef OPENSSL_NO_NEXTPROTONEG
+/* NPN TLS extension check */
+static int select_next_proto_cb(SSL* ssl, unsigned char** out,
+ unsigned char* outlen, const unsigned char* in,
+ unsigned int inlen, void* arg)
+{
+ if (nghttp2_select_next_protocol(out, outlen, in, inlen) <= 0) {
+ perf_log_warning("Server did not advertise %u", NGHTTP2_PROTO_VERSION_ID);
+ return SSL_TLSEXT_ERR_ALERT_WARNING;
+ }
+
+ return SSL_TLSEXT_ERR_OK;
+}
+#endif /* !OPENSSL_NO_NEXTPROTONEG */
+
+struct perf_net_socket* perf_net_doh_opensocket(const perf_sockaddr_t* server, const perf_sockaddr_t* local, size_t bufsize, void* data, perf_net_sent_cb_t sent, perf_net_event_cb_t event)
+{
+ struct perf__doh_socket* tmp = calloc(1, sizeof(struct perf__doh_socket)); // clang scan-build
+ struct perf_net_socket* sock = (struct perf_net_socket*)tmp;
+
+ if (!sock) {
+ perf_log_fatal("perf_net_doh_opensocket(): out of memory");
+ return 0; // needed for clang scan build
+ }
+
+ sock->recv = perf__doh_recv;
+ sock->sendto = perf__doh_sendto;
+ sock->close = perf__doh_close;
+ sock->sockeq = perf__doh_sockeq;
+ sock->sockready = perf__doh_sockready;
+ sock->have_more = perf__doh_have_more;
+
+ sock->data = data;
+ sock->sent = sent;
+ sock->event = event;
+
+ self->server = *server;
+ self->local = *local;
+ self->bufsize = bufsize;
+ if (self->bufsize > 0) {
+ self->bufsize *= 1024;
+ }
+ self->conning_event = perf_socket_event_connecting;
+ self->conn_event = perf_socket_event_connected;
+ PERF_MUTEX_INIT(&self->lock);
+
+ if (!(self->http2.payload.buf = malloc(MAX_EDNS_PACKET))) {
+ perf_log_fatal("perf_net_doh_opensocket(): out of memory");
+ }
+ self->http2.payload.buf_len = MAX_EDNS_PACKET;
+
+ if (!ssl_ctx) {
+#ifdef HAVE_TLS_METHOD
+ if (!(ssl_ctx = SSL_CTX_new(TLS_method()))) {
+ perf_log_fatal("SSL_CTX_new(): %s", ERR_error_string(ERR_get_error(), 0));
+ }
+ if (!SSL_CTX_set_min_proto_version(ssl_ctx, TLS1_2_VERSION)) {
+ perf_log_fatal("SSL_CTX_set_min_proto_version(TLS1_2_VERSION): %s", ERR_error_string(ERR_get_error(), 0));
+ }
+#else
+ if (!(ssl_ctx = SSL_CTX_new(SSLv23_client_method()))) {
+ perf_log_fatal("SSL_CTX_new(): %s", ERR_error_string(ERR_get_error(), 0));
+ }
+#endif
+ SSL_CTX_set_mode(ssl_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
+#ifndef OPENSSL_NO_NEXTPROTONEG
+ SSL_CTX_set_next_proto_select_cb(ssl_ctx, select_next_proto_cb, NULL);
+#endif /* !OPENSSL_NO_NEXTPROTONEG */
+#if OPENSSL_VERSION_NUMBER >= 0x10002000L
+ SSL_CTX_set_alpn_protos(ssl_ctx, (const unsigned char*)"\x02h2", 3);
+#endif // OPENSSL_VERSION_NUMBER >= 0x10002000L
+ }
+
+ /* setup HTTP/2 callbacks */
+ if (!_nghttp2_callbacks || !_nghttp2_option) {
+ PERF_LOCK(&_nghttp2_lock);
+ if (!_nghttp2_callbacks) {
+ if (nghttp2_session_callbacks_new(&_nghttp2_callbacks)) {
+ perf_log_fatal("Unable to create nghttp2 callbacks: out of memory");
+ }
+ nghttp2_session_callbacks_set_send_callback(_nghttp2_callbacks, _http2_send_cb);
+ nghttp2_session_callbacks_set_on_data_chunk_recv_callback(_nghttp2_callbacks, _http2_data_chunk_recv_cb);
+ nghttp2_session_callbacks_set_on_frame_recv_callback(_nghttp2_callbacks, _http2_frame_recv_cb);
+ nghttp2_session_callbacks_set_on_header_callback(_nghttp2_callbacks, _http2_on_header_callback);
+
+ // nghttp2_session_callbacks_set_recv_callback(_nghttp2_callbacks, _recv_callback);
+ }
+
+ /* setup HTTP/2 options */
+ if (!_nghttp2_option) {
+ if (nghttp2_option_new(&_nghttp2_option)) {
+ perf_log_fatal("Unable to create nghttp2 options: out of memory");
+ }
+ nghttp2_option_set_peer_max_concurrent_streams(_nghttp2_option, doh_max_concurr);
+ }
+ PERF_UNLOCK(&_nghttp2_lock);
+ }
+
+ perf__doh_connect(sock);
+
+ return sock;
+}
+
+static struct _doh_stats doh_stats;
+
+void perf_net_doh_stats_init()
+{
+ memset(&doh_stats, 0, sizeof(doh_stats));
+}
+
+void perf_net_doh_stats_compile(struct perf_net_socket* sock)
+{
+ int i;
+ for (i = 0; i < (sizeof(doh_stats.code) / sizeof(doh_stats.code[0])); i++) {
+ doh_stats.code[i] += self->stats.code[i];
+ }
+ doh_stats.unknown_code += self->stats.unknown_code;
+}
+
+void perf_net_doh_stats_print()
+{
+ printf("DNS-over-HTTPS statistics:\n\n");
+
+ printf(" HTTP/2 return codes: ");
+ bool first_code = true, no_codes = true;
+ int i;
+ for (i = 0; i < (sizeof(doh_stats.code) / sizeof(doh_stats.code[0])); i++) {
+ if (doh_stats.code[i]) {
+ if (first_code)
+ first_code = false;
+ else
+ printf(", ");
+ printf("%d: %zu", i + 100, doh_stats.code[i]);
+ no_codes = false;
+ }
+ }
+ if (doh_stats.unknown_code) {
+ if (!first_code)
+ printf(", ");
+ printf("unknown: %zu", doh_stats.unknown_code);
+ no_codes = false;
+ }
+ if (no_codes) {
+ printf("none");
+ }
+ printf("\n");
+
+ printf("\n");
+}