systemd/0071-backport-CVE-2018-21029-resolved-check-for-IP-in-certificate-when-using-DoT-.patch
2021-05-30 22:04:06 -04:00

52 lines
2.2 KiB
Diff

From 7f2f4faced3fda47e6b76ab73cde747cc20cf8b8 Mon Sep 17 00:00:00 2001
From: Iwan Timmer <irtimmer@gmail.com>
Date: Tue, 29 Oct 2019 20:32:18 +0100
Subject: [PATCH] resolved: check for IP in certificate when using DoT with
GnuTLS
Validate the IP address in the certificate for DNS-over-TLS in strict mode when GnuTLS is used. As this is not yet the case in contrast to the documentation.
---
src/resolve/resolved-dnstls-gnutls.c | 13 +++++++++++--
src/resolve/resolved-dnstls-gnutls.h | 1 +
2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/src/resolve/resolved-dnstls-gnutls.c b/src/resolve/resolved-dnstls-gnutls.c
index ea276d2c20..9e5e60fcce 100644
--- a/src/resolve/resolved-dnstls-gnutls.c
+++ b/src/resolve/resolved-dnstls-gnutls.c
@@ -55,8 +55,17 @@ int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server) {
server->dnstls_data.session_data.size = 0;
}
- if (server->manager->dns_over_tls_mode == DNS_OVER_TLS_YES)
- gnutls_session_set_verify_cert(gs, NULL, 0);
+ if (server->manager->dns_over_tls_mode == DNS_OVER_TLS_YES) {
+ stream->dnstls_data.validation.type = GNUTLS_DT_IP_ADDRESS;
+ if (server->family == AF_INET) {
+ stream->dnstls_data.validation.data = (unsigned char*) &server->address.in.s_addr;
+ stream->dnstls_data.validation.size = 4;
+ } else {
+ stream->dnstls_data.validation.data = server->address.in6.s6_addr;
+ stream->dnstls_data.validation.size = 16;
+ }
+ gnutls_session_set_verify_cert2(gs, &stream->dnstls_data.validation, 1, 0);
+ }
gnutls_handshake_set_timeout(gs, GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
diff --git a/src/resolve/resolved-dnstls-gnutls.h b/src/resolve/resolved-dnstls-gnutls.h
index af52f04fdf..d4da2017c3 100644
--- a/src/resolve/resolved-dnstls-gnutls.h
+++ b/src/resolve/resolved-dnstls-gnutls.h
@@ -18,6 +18,7 @@ struct DnsTlsServerData {
struct DnsTlsStreamData {
gnutls_session_t session;
+ gnutls_typed_vdata_st validation;
int handshake;
bool shutdown;
};
--
2.26.2