Adding upstream version 3.2.6.upstream/3.2.6upstream

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

1 files changed, 525 insertions, 0 deletions

diff --git a/src/utils/common/https.c b/src/utils/common/https.c
new file mode 100644
index 0000000..de98586
--- /dev/null
+++ b/src/utils/common/https.c
@@ -0,0 +1,525 @@
+/*  Copyright (C) 2023 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 <assert.h>
+#include <arpa/inet.h>
+#include <poll.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "contrib/base64url.h"
+#include "contrib/macros.h"
+#include "contrib/musl/inet_ntop.h"
+#include "contrib/openbsd/strlcat.h"
+#include "contrib/openbsd/strlcpy.h"
+#include "contrib/url-parser/url_parser.h"
+#include "libknot/errcode.h"
+#include "utils/common/https.h"
+#include "utils/common/msg.h"
+
+#define is_read(ctx) (ctx->stream == -1)
+
+int https_params_copy(https_params_t *dst, const https_params_t *src)
+{
+	if (dst == NULL || src == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	dst->enable = src->enable;
+	dst->method = src->method;
+	if (src->path != NULL) {
+		dst->path = strdup(src->path);
+		if (dst->path == NULL) {
+			return KNOT_ENOMEM;
+		}
+	}
+
+	return KNOT_EOK;
+}
+
+void https_params_clean(https_params_t *params)
+{
+	if (params == NULL) {
+		return;
+	}
+
+	params->enable = false;
+	params->method = GET;
+	free(params->path);
+	params->path = NULL;
+}
+
+#ifdef LIBNGHTTP2
+
+#define HTTP_STATUS_SUCCESS	200
+#define HTTPS_MAX_STREAMS	16
+#define HTTPS_AUTHORITY_LEN	(INET6_ADDRSTRLEN + 2)
+
+#define MAKE_NV(K, KS, V, VS) \
+	{ (uint8_t *)K, (uint8_t *)V, KS, VS, NGHTTP2_NV_FLAG_NONE }
+
+#define MAKE_STATIC_NV(K, V) \
+	MAKE_NV(K, sizeof(K) - 1, V, sizeof(V) - 1)
+
+static const char default_path[] = "/dns-query";
+static const char default_query[] = "?dns=";
+
+static const nghttp2_settings_entry settings[] = {
+	{ NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, HTTPS_MAX_STREAMS }
+};
+
+const gnutls_datum_t doh_alpn = {
+	.data = (unsigned char *)"h2",
+	.size = 2
+};
+
+static bool https_status_is_redirect(unsigned long status)
+{
+	switch (status) {
+		case 301UL:
+		case 302UL:
+		case 307UL:
+		case 308UL:
+			return true;
+	}
+	return false;
+}
+
+static ssize_t https_send_callback(nghttp2_session *session, const uint8_t *data,
+                                   size_t length, int flags, void *user_data)
+{
+	assert(user_data);
+
+	gnutls_session_t tls_session = ((https_ctx_t *)user_data)->tls->session;
+	ssize_t len = 0;
+
+	gnutls_record_cork(tls_session);
+	if ((len = gnutls_record_send(tls_session, data, length)) <= 0) {
+		WARN("TLS, failed to send");
+		return KNOT_NET_ESEND;
+	}
+	return len;
+}
+
+static int https_on_frame_send_callback(nghttp2_session *session, const nghttp2_frame *frame,
+                                        void *user_data)
+{
+	assert(user_data);
+
+	gnutls_session_t tls_session = ((https_ctx_t *)user_data)->tls->session;
+	while (gnutls_record_check_corked(tls_session) > 0) {
+		int ret = gnutls_record_uncork(tls_session, 0);
+		if (ret < 0 && gnutls_error_is_fatal(ret) != 0) {
+			WARN("TLS, failed to send (%s)", gnutls_strerror(ret));
+			return KNOT_NET_ESEND;
+		}
+	}
+	return KNOT_EOK;
+}
+
+static ssize_t https_recv_callback(nghttp2_session *session, uint8_t *data, size_t length,
+                                   int flags, void *user_data)
+{
+	assert(user_data);
+
+	https_ctx_t *ctx = (https_ctx_t *)user_data;
+	struct pollfd pfd = {
+		.fd = ctx->tls->sockfd,
+		.events = POLLIN,
+		.revents = 0,
+	};
+
+	ssize_t ret = 0;
+	while ((ret = gnutls_record_recv(ctx->tls->session, data, length)) <= 0) {
+		if (is_read(ctx)) { //Unblock `nghttp2_session_recv(nghttp2_session)`
+			return NGHTTP2_ERR_WOULDBLOCK;
+		}
+		if (ret == 0) {
+			WARN("TLS, peer has closed the connection");
+			return KNOT_NET_ERECV;
+		} else if (gnutls_error_is_fatal(ret)) {
+			WARN("TLS, failed to receive reply (%s)",
+			     gnutls_strerror(ret));
+			return KNOT_NET_ERECV;
+		} else if (poll(&pfd, 1, 1000 * ctx->tls->wait) != 1) {
+			WARN("TLS, peer took too long to respond");
+			return KNOT_ETIMEOUT;
+		}
+	}
+
+	return ret;
+}
+
+static int https_on_data_chunk_recv_callback(nghttp2_session *session, uint8_t flags, int32_t stream_id,
+                                             const uint8_t *data, size_t len, void *user_data)
+{
+	assert(user_data);
+
+	https_ctx_t *ctx = (https_ctx_t *)user_data;
+	if (ctx->stream == stream_id) {
+		int cpy_len = MIN(len, ctx->recv_buflen);
+		memcpy(ctx->recv_buf, data, cpy_len);
+		ctx->recv_buf += cpy_len;
+		ctx->recv_buflen -= cpy_len;
+	}
+	return KNOT_EOK;
+}
+
+static int https_on_stream_close_callback(nghttp2_session *session, int32_t stream_id, uint32_t error_code, void *user_data)
+{
+	assert(user_data);
+
+	https_ctx_t *ctx = (https_ctx_t *)user_data;
+	if (ctx->stream == stream_id) {
+		ctx->stream = -1;
+	}
+	return KNOT_EOK;
+}
+
+static int https_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 *user_data)
+{
+	assert(user_data);
+	https_ctx_t *ctx = (https_ctx_t *)user_data;
+
+	if (!strncasecmp(":status", (const char *)name, namelen)) {
+		char *end;
+		long status;
+		status = strtoul((const char *)value, &end, 10);
+		if (value != (const uint8_t *)end) {
+			ctx->status = status;
+		}
+	}
+	else if (!strncasecmp("location", (const char *)name, namelen) &&
+		 https_status_is_redirect(ctx->status)) {
+		struct http_parser_url redirect_url;
+		http_parser_parse_url((const char *)value, valuelen, 0, &redirect_url);
+
+		bool r_auth = redirect_url.field_set & (1 << UF_HOST);
+		bool r_path = redirect_url.field_set & (1 << UF_PATH);
+		char *old_auth = ctx->authority, *old_path = ctx->path;
+
+		if (r_auth) {
+			ctx->authority = strndup((const char *)(value + redirect_url.field_data[UF_HOST].off),
+			                         redirect_url.field_data[UF_HOST].len);
+		}
+		if (r_path) {
+			ctx->path = strndup((const char *)(value + redirect_url.field_data[UF_PATH].off),
+			                    redirect_url.field_data[UF_PATH].len);
+		}
+		WARN("HTTP redirect (%s%s)->(%s%s)", old_auth, old_path, ctx->authority, ctx->path);
+		if (r_auth) {
+			free(old_auth);
+		}
+		if (r_path) {
+			free(old_path);
+		}
+		return https_send_dns_query(ctx, ctx->send_buf, ctx->send_buflen);
+	}
+	return KNOT_EOK;
+}
+
+int https_ctx_init(https_ctx_t *ctx, tls_ctx_t *tls_ctx, const https_params_t *params)
+{
+	if (ctx == NULL || tls_ctx == NULL || params == NULL) {
+		return KNOT_EINVAL;
+	}
+	if (ctx->session != NULL) { // Already initialized before
+		return KNOT_EINVAL;
+	}
+	if (!params->enable) {
+		return KNOT_EINVAL;
+	}
+
+	nghttp2_session_callbacks *callbacks;
+	nghttp2_session_callbacks_new(&callbacks);
+	nghttp2_session_callbacks_set_send_callback(callbacks, https_send_callback);
+	nghttp2_session_callbacks_set_on_frame_send_callback(callbacks, https_on_frame_send_callback);
+	nghttp2_session_callbacks_set_recv_callback(callbacks, https_recv_callback);
+	nghttp2_session_callbacks_set_on_data_chunk_recv_callback(callbacks, https_on_data_chunk_recv_callback);
+	nghttp2_session_callbacks_set_on_header_callback(callbacks, https_on_header_callback);
+	nghttp2_session_callbacks_set_on_stream_close_callback(callbacks, https_on_stream_close_callback);
+
+	int ret = nghttp2_session_client_new(&(ctx->session), callbacks, ctx);
+	if (ret != 0) {
+		return KNOT_EINVAL;
+	}
+
+	nghttp2_session_callbacks_del(callbacks);
+
+	if (pthread_mutex_init(&ctx->recv_mx, NULL) != 0) {
+		return KNOT_EINVAL;
+	}
+
+	ctx->tls = tls_ctx;
+	ctx->params = *params;
+	ctx->authority = (tls_ctx->params->hostname) ? strdup(tls_ctx->params->hostname) : NULL;
+	ctx->path = strdup((ctx->params.path) ? ctx->params.path : (char *)default_path);
+	ctx->stream = -1;
+
+	return KNOT_EOK;
+}
+
+static int sockaddr_to_authority(char *buf, const size_t buf_len, const struct sockaddr_storage *ss)
+{
+	if (buf == NULL || ss == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	const char *out = NULL;
+
+	/* Convert IPv6 network address string. */
+	if (ss->ss_family == AF_INET6) {
+		if (buf_len < HTTPS_AUTHORITY_LEN) {
+			return KNOT_EINVAL;
+		}
+
+		const struct sockaddr_in6 *s = (const struct sockaddr_in6 *)ss;
+		buf[0] = '[';
+
+		out = knot_inet_ntop(ss->ss_family, &s->sin6_addr, buf + 1, buf_len - 1);
+		if (out == NULL) {
+			return KNOT_EINVAL;
+		}
+
+		buf += strlen(buf);
+		buf[0] = ']';
+		buf[1] = '\0';
+	/* Convert IPv4 network address string. */
+	} else if (ss->ss_family == AF_INET) {
+		if (buf_len < INET_ADDRSTRLEN) {
+			return KNOT_EINVAL;
+		}
+
+		const struct sockaddr_in *s = (const struct sockaddr_in *)ss;
+
+		out = knot_inet_ntop(ss->ss_family, &s->sin_addr, buf, buf_len);
+		if (out == NULL) {
+			return KNOT_EINVAL;
+		}
+	/* Unknown network address family. */
+	} else {
+		return KNOT_EINVAL;
+	}
+
+	return KNOT_EOK;
+}
+
+int https_ctx_connect(https_ctx_t *ctx, int sockfd, bool fastopen,
+                      struct sockaddr_storage *addr)
+{
+	if (ctx == NULL || addr == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	// Create TLS connection
+	int ret = tls_ctx_connect(ctx->tls, sockfd, fastopen, addr);
+	if (ret != KNOT_EOK) {
+		return ret;
+	}
+
+	// Perform HTTP handshake
+	ret = nghttp2_submit_settings(ctx->session, NGHTTP2_FLAG_NONE, settings,
+	                              sizeof(settings) / sizeof(*settings));
+	if (ret != 0) {
+		return KNOT_NET_ESOCKET;
+	}
+	ret = nghttp2_session_send(ctx->session);
+	if (ret != 0) {
+		return KNOT_NET_ESOCKET;
+	}
+
+	// Save authority server
+	if (ctx->authority == NULL) {
+		ctx->authority = calloc(HTTPS_AUTHORITY_LEN, 1);
+		ret = sockaddr_to_authority(ctx->authority, HTTPS_AUTHORITY_LEN, addr);
+		if (ret != KNOT_EOK) {
+			free(ctx->authority);
+			ctx->authority = NULL;
+			return KNOT_EINVAL;
+		}
+	}
+
+	return KNOT_EOK;
+}
+
+static int https_send_dns_query_common(https_ctx_t *ctx, nghttp2_nv *hdrs, size_t hdrs_len, nghttp2_data_provider *data_provider)
+{
+	assert(hdrs != NULL && hdrs_len > 0);
+
+	ctx->stream = nghttp2_submit_request(ctx->session, NULL, hdrs, hdrs_len,
+	                                     data_provider, NULL);
+	if (ctx->stream < 0) {
+		return KNOT_NET_ESEND;
+	}
+	int ret = nghttp2_session_send(ctx->session);
+	if (ret != 0) {
+		return KNOT_NET_ESEND;
+	}
+
+	return KNOT_EOK;
+}
+
+static int https_send_dns_query_get(https_ctx_t *ctx)
+{
+	const size_t dns_query_len = strlen(ctx->path) +
+	                             sizeof(default_query) +
+	                             (ctx->send_buflen * 4) / 3 + 3;
+	char dns_query[dns_query_len];
+	strlcpy(dns_query, ctx->path, dns_query_len);
+	strlcat(dns_query, default_query, dns_query_len);
+
+	size_t tmp_strlen = strlen(dns_query);
+	int32_t ret = knot_base64url_encode(ctx->send_buf, ctx->send_buflen,
+		(uint8_t *)(dns_query + tmp_strlen), dns_query_len - tmp_strlen - 1);
+	if (ret < 0) {
+		return KNOT_EINVAL;
+	}
+
+	nghttp2_nv hdrs[] = {
+		MAKE_STATIC_NV(":method", "GET"),
+		MAKE_STATIC_NV(":scheme", "https"),
+		MAKE_NV(":authority", 10, ctx->authority, strlen(ctx->authority)),
+		MAKE_NV(":path", 5, dns_query, tmp_strlen + ret),
+		MAKE_STATIC_NV("accept", "application/dns-message"),
+	};
+
+	return https_send_dns_query_common(ctx, hdrs, sizeof(hdrs) / sizeof(*hdrs),
+	                                   NULL);
+}
+
+static ssize_t https_send_data_callback(nghttp2_session *session, int32_t stream_id,
+                                        uint8_t *buf, size_t length, uint32_t *data_flags,
+                                        nghttp2_data_source *source, void *user_data)
+{
+	https_data_provider_t *buffer = source->ptr;
+	ssize_t sent = (length < buffer->buf_len) ? length : buffer->buf_len;
+
+	memcpy(buf, buffer->buf, sent);
+	buffer->buf += sent;
+	buffer->buf_len -= sent;
+	if (!buffer->buf_len) {
+		*data_flags |= NGHTTP2_DATA_FLAG_EOF;
+	}
+
+	return sent;
+}
+
+static int https_send_dns_query_post(https_ctx_t *ctx)
+{
+	                                             // size of number in text form (base 10)
+	char content_length[sizeof(size_t) * 3 + 1]; // limit for x->inf: log10(2^(8*sizeof(x))-1)/sizeof(x) = 2,408239965 -> 3
+	int content_length_len = sprintf(content_length, "%zu", ctx->send_buflen);
+
+	nghttp2_nv hdrs[] = {
+		MAKE_STATIC_NV(":method", "POST"),
+		MAKE_STATIC_NV(":scheme", "https"),
+		MAKE_NV(":authority", 10, ctx->authority, strlen(ctx->authority)),
+		MAKE_NV(":path", 5, ctx->path, strlen(ctx->path)),
+		MAKE_STATIC_NV("accept", "application/dns-message"),
+		MAKE_STATIC_NV("content-type", "application/dns-message"),
+		MAKE_NV("content-length", 14, content_length, content_length_len)
+	};
+
+	https_data_provider_t data = {
+		.buf = ctx->send_buf,
+		.buf_len = ctx->send_buflen
+	};
+
+	nghttp2_data_provider data_provider = {
+		.source.ptr = &data,
+		.read_callback = https_send_data_callback
+	};
+
+	return https_send_dns_query_common(ctx, hdrs, sizeof(hdrs) / sizeof(*hdrs),
+	                                   &data_provider);
+}
+
+int https_send_dns_query(https_ctx_t *ctx, const uint8_t *buf, const size_t buf_len)
+{
+	if (ctx == NULL || buf == NULL || buf_len == 0) {
+		return KNOT_EINVAL;
+	}
+
+	ctx->send_buf = buf;
+	ctx->send_buflen = buf_len;
+
+	assert(ctx->params.method == POST || ctx->params.method == GET);
+
+	if (ctx->params.method == POST) {
+		return https_send_dns_query_post(ctx);
+	} else {
+		return https_send_dns_query_get(ctx);
+	}
+}
+
+int https_recv_dns_response(https_ctx_t *ctx, uint8_t *buf, const size_t buf_len)
+{
+	if (ctx == NULL || buf == NULL || buf_len == 0) {
+		return KNOT_EINVAL;
+	}
+
+	pthread_mutex_lock(&ctx->recv_mx);
+	ctx->recv_buf = buf;
+	ctx->recv_buflen = buf_len;
+
+	int ret = nghttp2_session_recv(ctx->session);
+	if (ret != 0) {
+		pthread_mutex_unlock(&ctx->recv_mx);
+		return KNOT_NET_ERECV;
+	}
+	ctx->recv_buf = NULL;
+
+	pthread_mutex_unlock(&ctx->recv_mx);
+
+	if (ctx->status != HTTP_STATUS_SUCCESS) {
+		print_https(ctx);
+		return KNOT_NET_ERECV;
+	}
+
+	assert(buf_len >= ctx->recv_buflen);
+	return buf_len - ctx->recv_buflen;
+}
+
+void https_ctx_deinit(https_ctx_t *ctx)
+{
+	if (ctx == NULL) {
+		return;
+	}
+
+	nghttp2_session_del(ctx->session);
+	ctx->session = NULL;
+	pthread_mutex_destroy(&ctx->recv_mx);
+	free(ctx->path);
+	ctx->path = NULL;
+	free(ctx->authority);
+	ctx->authority = NULL;
+}
+
+void print_https(const https_ctx_t *ctx)
+{
+	if (!ctx || !ctx->params.enable || !ctx->authority || !ctx->path) {
+		return;
+	}
+
+	printf(";; HTTP session (HTTP/2-%s)-(%s%s)-(status: %lu)\n",
+	       ctx->params.method == POST ? "POST" : "GET", ctx->authority,
+	       ctx->path, ctx->status);
+}
+
+#endif //LIBNGHTTP2