resolved: refactor GnuTLS specific code in separate source file
This is a first step towards supporting alternative TLS implementations for DNS-over-TLS. Co-authored-by: Filipe Brandenburger <filbranden@google.com>
This commit is contained in:
parent
48c20af38e
commit
6016fcb0ea
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@ -63,6 +63,7 @@ systemd_resolved_sources = files('''
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resolved-dns-stub.c
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resolved-dns-stub.c
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resolved-etc-hosts.h
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resolved-etc-hosts.h
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resolved-etc-hosts.c
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resolved-etc-hosts.c
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resolved-dnstls.h
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'''.split())
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'''.split())
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resolvectl_sources = files('''
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resolvectl_sources = files('''
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@ -141,6 +142,7 @@ systemd_resolved_sources += [resolved_gperf_c, resolved_dnssd_gperf_c]
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systemd_resolved_dependencies = [threads, libgpg_error, libm, libidn]
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systemd_resolved_dependencies = [threads, libgpg_error, libm, libidn]
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if conf.get('ENABLE_DNS_OVER_TLS') == 1
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if conf.get('ENABLE_DNS_OVER_TLS') == 1
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systemd_resolved_sources += [files(['resolved-dnstls-gnutls.c', 'resolved-dnstls-gnutls.h'])]
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systemd_resolved_dependencies += [libgnutls]
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systemd_resolved_dependencies += [libgnutls]
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endif
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endif
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@ -81,8 +81,7 @@ int dns_server_new(
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s->linked = true;
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s->linked = true;
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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/* Do not verify cerificate */
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dnstls_server_init(s);
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gnutls_certificate_allocate_credentials(&s->tls_cert_cred);
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#endif
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#endif
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/* A new DNS server that isn't fallback is added and the one
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/* A new DNS server that isn't fallback is added and the one
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@ -122,11 +121,7 @@ DnsServer* dns_server_unref(DnsServer *s) {
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dns_stream_unref(s->stream);
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dns_stream_unref(s->stream);
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_cert_cred)
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dnstls_server_free(s);
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gnutls_certificate_free_credentials(s->tls_cert_cred);
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if (s->tls_session_data.data)
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gnutls_free(s->tls_session_data.data);
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#endif
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#endif
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free(s->server_string);
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free(s->server_string);
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@ -3,10 +3,6 @@
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#include "in-addr-util.h"
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#include "in-addr-util.h"
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#if ENABLE_DNS_OVER_TLS
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#include <gnutls/gnutls.h>
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#endif
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typedef struct DnsServer DnsServer;
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typedef struct DnsServer DnsServer;
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typedef enum DnsServerType {
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typedef enum DnsServerType {
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@ -41,6 +37,9 @@ int dns_server_feature_level_from_string(const char *s) _pure_;
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#include "resolved-link.h"
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#include "resolved-link.h"
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#include "resolved-manager.h"
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#include "resolved-manager.h"
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#if ENABLE_DNS_OVER_TLS
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#include "resolved-dnstls.h"
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#endif
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struct DnsServer {
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struct DnsServer {
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Manager *manager;
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Manager *manager;
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@ -58,8 +57,7 @@ struct DnsServer {
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DnsStream *stream;
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DnsStream *stream;
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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gnutls_certificate_credentials_t tls_cert_cred;
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DnsTlsServerData dnstls_data;
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gnutls_datum_t tls_session_data;
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#endif
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#endif
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DnsServerFeatureLevel verified_feature_level;
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DnsServerFeatureLevel verified_feature_level;
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@ -11,8 +11,6 @@
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#define DNS_STREAM_TIMEOUT_USEC (10 * USEC_PER_SEC)
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#define DNS_STREAM_TIMEOUT_USEC (10 * USEC_PER_SEC)
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#define DNS_STREAMS_MAX 128
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#define DNS_STREAMS_MAX 128
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#define WRITE_TLS_DATA 1
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static void dns_stream_stop(DnsStream *s) {
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static void dns_stream_stop(DnsStream *s) {
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assert(s);
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assert(s);
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@ -45,14 +43,11 @@ static int dns_stream_complete(DnsStream *s, int error) {
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assert(s);
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assert(s);
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_session && IN_SET(error, ETIMEDOUT, 0)) {
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if (s->encrypted) {
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int r;
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int r;
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r = gnutls_bye(s->tls_session, GNUTLS_SHUT_RDWR);
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r = dnstls_stream_shutdown(s, error);
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if (r == GNUTLS_E_AGAIN && !s->tls_bye) {
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if (r != -EAGAIN)
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dns_stream_ref(s); /* keep reference for closing TLS session */
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s->tls_bye = true;
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} else
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dns_stream_stop(s);
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dns_stream_stop(s);
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} else
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} else
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#endif
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#endif
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@ -191,32 +186,22 @@ static int dns_stream_identify(DnsStream *s) {
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return 0;
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return 0;
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}
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}
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static ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags) {
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ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags) {
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ssize_t r;
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ssize_t r;
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assert(s);
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assert(s);
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assert(iov);
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assert(iov);
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_session && !(flags & WRITE_TLS_DATA)) {
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if (s->encrypted && !(flags & DNS_STREAM_WRITE_TLS_DATA)) {
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ssize_t ss;
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ssize_t ss;
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size_t i;
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size_t i;
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r = 0;
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r = 0;
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for (i = 0; i < iovcnt; i++) {
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for (i = 0; i < iovcnt; i++) {
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ss = gnutls_record_send(s->tls_session, iov[i].iov_base, iov[i].iov_len);
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ss = dnstls_stream_write(s, iov[i].iov_base, iov[i].iov_len);
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if (ss < 0) {
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if (ss < 0)
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switch(ss) {
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return ss;
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case GNUTLS_E_INTERRUPTED:
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return -EINTR;
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case GNUTLS_E_AGAIN:
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return -EAGAIN;
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default:
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log_debug("Failed to invoke gnutls_record_send: %s", gnutls_strerror(ss));
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return -EIO;
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}
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}
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r += ss;
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r += ss;
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if (ss != (ssize_t) iov[i].iov_len)
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if (ss != (ssize_t) iov[i].iov_len)
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@ -258,28 +243,9 @@ static ssize_t dns_stream_read(DnsStream *s, void *buf, size_t count) {
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ssize_t ss;
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ssize_t ss;
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_session) {
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if (s->encrypted)
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ss = gnutls_record_recv(s->tls_session, buf, count);
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ss = dnstls_stream_read(s, buf, count);
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if (ss < 0) {
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else
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switch(ss) {
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case GNUTLS_E_INTERRUPTED:
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return -EINTR;
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case GNUTLS_E_AGAIN:
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return -EAGAIN;
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default:
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log_debug("Failed to invoke gnutls_record_send: %s", gnutls_strerror(ss));
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return -EIO;
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}
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} else if (s->on_connection) {
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int r;
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r = s->on_connection(s);
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s->on_connection = NULL; /* only call once */
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if (r < 0)
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return r;
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}
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} else
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#endif
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#endif
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{
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{
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ss = read(s->fd, buf, count);
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ss = read(s->fd, buf, count);
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@ -290,22 +256,6 @@ static ssize_t dns_stream_read(DnsStream *s, void *buf, size_t count) {
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return ss;
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return ss;
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}
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}
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#if ENABLE_DNS_OVER_TLS
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static ssize_t dns_stream_tls_writev(gnutls_transport_ptr_t p, const giovec_t * iov, int iovcnt) {
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int r;
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assert(p);
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r = dns_stream_writev((DnsStream*) p, (struct iovec*) iov, iovcnt, WRITE_TLS_DATA);
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if (r < 0) {
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errno = -r;
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return -1;
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}
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return r;
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}
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#endif
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static int on_stream_timeout(sd_event_source *es, usec_t usec, void *userdata) {
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static int on_stream_timeout(sd_event_source *es, usec_t usec, void *userdata) {
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DnsStream *s = userdata;
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DnsStream *s = userdata;
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@ -321,36 +271,13 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use
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assert(s);
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assert(s);
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_bye) {
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if (s->encrypted) {
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assert(s->tls_session);
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r = dnstls_stream_on_io(s);
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r = gnutls_bye(s->tls_session, GNUTLS_SHUT_RDWR);
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if (r != GNUTLS_E_AGAIN) {
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s->tls_bye = false;
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dns_stream_unref(s);
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}
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return 0;
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}
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if (s->tls_handshake < 0) {
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assert(s->tls_session);
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s->tls_handshake = gnutls_handshake(s->tls_session);
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if (s->tls_handshake >= 0) {
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if (s->on_connection && !(gnutls_session_get_flags(s->tls_session) & GNUTLS_SFLAGS_FALSE_START)) {
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r = s->on_connection(s);
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s->on_connection = NULL; /* only call once */
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if (r < 0)
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return r;
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}
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} else {
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if (gnutls_error_is_fatal(s->tls_handshake))
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return dns_stream_complete(s, ECONNREFUSED);
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else
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return 0;
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}
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if (r == DNSTLS_STREAM_CLOSED || r == -EAGAIN)
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return 0;
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else if (r < 0)
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return dns_stream_complete(s, -r);
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}
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}
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#endif
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#endif
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@ -506,8 +433,8 @@ DnsStream *dns_stream_unref(DnsStream *s) {
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}
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}
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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if (s->tls_session)
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if (s->encrypted)
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gnutls_deinit(s->tls_session);
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dnstls_stream_free(s);
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#endif
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#endif
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ORDERED_SET_FOREACH(p, s->write_queue, i)
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ORDERED_SET_FOREACH(p, s->write_queue, i)
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@ -586,21 +513,6 @@ int dns_stream_new(Manager *m, DnsStream **ret, DnsProtocol protocol, int fd, co
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return 0;
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return 0;
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}
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}
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#if ENABLE_DNS_OVER_TLS
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int dns_stream_connect_tls(DnsStream *s, gnutls_session_t tls_session) {
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gnutls_transport_set_ptr2(tls_session, (gnutls_transport_ptr_t) (long) s->fd, s);
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gnutls_transport_set_vec_push_function(tls_session, &dns_stream_tls_writev);
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s->encrypted = true;
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s->tls_session = tls_session;
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s->tls_handshake = gnutls_handshake(tls_session);
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if (s->tls_handshake < 0 && gnutls_error_is_fatal(s->tls_handshake))
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return -ECONNREFUSED;
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return 0;
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}
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#endif
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int dns_stream_write_packet(DnsStream *s, DnsPacket *p) {
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int dns_stream_write_packet(DnsStream *s, DnsPacket *p) {
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int r;
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int r;
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#include "resolved-dns-packet.h"
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#include "resolved-dns-packet.h"
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#include "resolved-dns-transaction.h"
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#include "resolved-dns-transaction.h"
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#include "resolved-manager.h"
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#include "resolved-manager.h"
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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#include <gnutls/gnutls.h>
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#include "resolved-dnstls.h"
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#endif
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#endif
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#define DNS_STREAM_WRITE_TLS_DATA 1
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/* Streams are used by three subsystems:
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/* Streams are used by three subsystems:
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*
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*
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* 1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP
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* 1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP
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socklen_t tfo_salen;
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socklen_t tfo_salen;
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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gnutls_session_t tls_session;
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DnsTlsStreamData dnstls_data;
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int tls_handshake;
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bool tls_bye;
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#endif
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#endif
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sd_event_source *io_event_source;
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sd_event_source *io_event_source;
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@ -69,7 +68,7 @@ struct DnsStream {
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int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
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int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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int dns_stream_connect_tls(DnsStream *s, gnutls_session_t tls_session);
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int dns_stream_connect_tls(DnsStream *s, void *tls_session);
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#endif
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#endif
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DnsStream *dns_stream_unref(DnsStream *s);
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DnsStream *dns_stream_unref(DnsStream *s);
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DnsStream *dns_stream_ref(DnsStream *s);
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DnsStream *dns_stream_ref(DnsStream *s);
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@ -77,6 +76,7 @@ DnsStream *dns_stream_ref(DnsStream *s);
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DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref);
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DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref);
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int dns_stream_write_packet(DnsStream *s, DnsPacket *p);
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int dns_stream_write_packet(DnsStream *s, DnsPacket *p);
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ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags);
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static inline bool DNS_STREAM_QUEUED(DnsStream *s) {
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static inline bool DNS_STREAM_QUEUED(DnsStream *s) {
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assert(s);
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assert(s);
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@ -11,11 +11,10 @@
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#include "resolved-dns-cache.h"
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#include "resolved-dns-cache.h"
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#include "resolved-dns-transaction.h"
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#include "resolved-dns-transaction.h"
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#include "resolved-llmnr.h"
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#include "resolved-llmnr.h"
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#include "string-table.h"
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#if ENABLE_DNS_OVER_TLS
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#if ENABLE_DNS_OVER_TLS
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#include <gnutls/socket.h>
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#include "resolved-dnstls.h"
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#endif
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#endif
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#include "string-table.h"
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#define TRANSACTIONS_MAX 4096
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#define TRANSACTIONS_MAX 4096
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#define TRANSACTION_TCP_TIMEOUT_USEC (10U*USEC_PER_SEC)
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#define TRANSACTION_TCP_TIMEOUT_USEC (10U*USEC_PER_SEC)
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||||||
|
@ -503,20 +502,6 @@ static int dns_transaction_on_stream_packet(DnsTransaction *t, DnsPacket *p) {
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
||||||
static int on_stream_connection(DnsStream *s) {
|
|
||||||
#if ENABLE_DNS_OVER_TLS
|
|
||||||
/* Store TLS Ticket for faster succesive TLS handshakes */
|
|
||||||
if (s->tls_session && s->server) {
|
|
||||||
if (s->server->tls_session_data.data)
|
|
||||||
gnutls_free(s->server->tls_session_data.data);
|
|
||||||
|
|
||||||
gnutls_session_get_data2(s->tls_session, &s->server->tls_session_data);
|
|
||||||
}
|
|
||||||
#endif
|
|
||||||
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
static int on_stream_complete(DnsStream *s, int error) {
|
static int on_stream_complete(DnsStream *s, int error) {
|
||||||
_cleanup_(dns_stream_unrefp) DnsStream *p = NULL;
|
_cleanup_(dns_stream_unrefp) DnsStream *p = NULL;
|
||||||
DnsTransaction *t, *n;
|
DnsTransaction *t, *n;
|
||||||
|
@ -578,9 +563,6 @@ static int dns_transaction_emit_tcp(DnsTransaction *t) {
|
||||||
_cleanup_(dns_stream_unrefp) DnsStream *s = NULL;
|
_cleanup_(dns_stream_unrefp) DnsStream *s = NULL;
|
||||||
union sockaddr_union sa;
|
union sockaddr_union sa;
|
||||||
int r;
|
int r;
|
||||||
#if ENABLE_DNS_OVER_TLS
|
|
||||||
gnutls_session_t gs;
|
|
||||||
#endif
|
|
||||||
|
|
||||||
assert(t);
|
assert(t);
|
||||||
|
|
||||||
|
@ -655,32 +637,12 @@ static int dns_transaction_emit_tcp(DnsTransaction *t) {
|
||||||
#if ENABLE_DNS_OVER_TLS
|
#if ENABLE_DNS_OVER_TLS
|
||||||
if (DNS_SERVER_FEATURE_LEVEL_IS_TLS(t->current_feature_level)) {
|
if (DNS_SERVER_FEATURE_LEVEL_IS_TLS(t->current_feature_level)) {
|
||||||
assert(t->server);
|
assert(t->server);
|
||||||
|
r = dnstls_stream_connect_tls(s, t->server);
|
||||||
r = gnutls_init(&gs, GNUTLS_CLIENT | GNUTLS_ENABLE_FALSE_START | GNUTLS_NONBLOCK);
|
|
||||||
if (r < 0)
|
|
||||||
return r;
|
|
||||||
|
|
||||||
/* As DNS-over-TLS is a recent protocol, older TLS versions can be disabled */
|
|
||||||
r = gnutls_priority_set_direct(gs, "NORMAL:-VERS-ALL:+VERS-TLS1.2", NULL);
|
|
||||||
if (r < 0)
|
|
||||||
return r;
|
|
||||||
|
|
||||||
r = gnutls_credentials_set(gs, GNUTLS_CRD_CERTIFICATE, t->server->tls_cert_cred);
|
|
||||||
if (r < 0)
|
|
||||||
return r;
|
|
||||||
|
|
||||||
if (t->server->tls_session_data.size > 0)
|
|
||||||
gnutls_session_set_data(gs, t->server->tls_session_data.data, t->server->tls_session_data.size);
|
|
||||||
|
|
||||||
gnutls_handshake_set_timeout(gs, GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
|
|
||||||
|
|
||||||
r = dns_stream_connect_tls(s, gs);
|
|
||||||
if (r < 0)
|
if (r < 0)
|
||||||
return r;
|
return r;
|
||||||
}
|
}
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
s->on_connection = on_stream_connection;
|
|
||||||
s->complete = on_stream_complete;
|
s->complete = on_stream_complete;
|
||||||
s->on_packet = dns_stream_on_packet;
|
s->on_packet = dns_stream_on_packet;
|
||||||
|
|
||||||
|
|
198
src/resolve/resolved-dnstls-gnutls.c
Normal file
198
src/resolve/resolved-dnstls-gnutls.c
Normal file
|
@ -0,0 +1,198 @@
|
||||||
|
/* SPDX-License-Identifier: LGPL-2.1+ */
|
||||||
|
|
||||||
|
#if !ENABLE_DNS_OVER_TLS || !HAVE_GNUTLS
|
||||||
|
#error This source file requires DNS-over-TLS to be enabled and GnuTLS to be available.
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include "resolved-dnstls.h"
|
||||||
|
#include "resolved-dns-stream.h"
|
||||||
|
|
||||||
|
#include <gnutls/socket.h>
|
||||||
|
|
||||||
|
DEFINE_TRIVIAL_CLEANUP_FUNC(gnutls_session_t, gnutls_deinit);
|
||||||
|
|
||||||
|
static ssize_t dnstls_stream_writev(gnutls_transport_ptr_t p, const giovec_t *iov, int iovcnt) {
|
||||||
|
int r;
|
||||||
|
|
||||||
|
assert(p);
|
||||||
|
|
||||||
|
r = dns_stream_writev((DnsStream*) p, (const struct iovec*) iov, iovcnt, DNS_STREAM_WRITE_TLS_DATA);
|
||||||
|
if (r < 0) {
|
||||||
|
errno = -r;
|
||||||
|
return -1;
|
||||||
|
}
|
||||||
|
|
||||||
|
return r;
|
||||||
|
}
|
||||||
|
|
||||||
|
int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server) {
|
||||||
|
_cleanup_(gnutls_deinitp) gnutls_session_t gs;
|
||||||
|
int r;
|
||||||
|
|
||||||
|
assert(stream);
|
||||||
|
assert(server);
|
||||||
|
|
||||||
|
r = gnutls_init(&gs, GNUTLS_CLIENT | GNUTLS_ENABLE_FALSE_START | GNUTLS_NONBLOCK);
|
||||||
|
if (r < 0)
|
||||||
|
return r;
|
||||||
|
|
||||||
|
/* As DNS-over-TLS is a recent protocol, older TLS versions can be disabled */
|
||||||
|
r = gnutls_priority_set_direct(gs, "NORMAL:-VERS-ALL:+VERS-TLS1.2", NULL);
|
||||||
|
if (r < 0)
|
||||||
|
return r;
|
||||||
|
|
||||||
|
r = gnutls_credentials_set(gs, GNUTLS_CRD_CERTIFICATE, server->dnstls_data.cert_cred);
|
||||||
|
if (r < 0)
|
||||||
|
return r;
|
||||||
|
|
||||||
|
if (server->dnstls_data.session_data.size > 0) {
|
||||||
|
gnutls_session_set_data(gs, server->dnstls_data.session_data.data, server->dnstls_data.session_data.size);
|
||||||
|
|
||||||
|
// Clear old session ticket
|
||||||
|
gnutls_free(server->dnstls_data.session_data.data);
|
||||||
|
server->dnstls_data.session_data.data = NULL;
|
||||||
|
server->dnstls_data.session_data.size = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
gnutls_handshake_set_timeout(gs, GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
|
||||||
|
|
||||||
|
gnutls_transport_set_ptr2(gs, (gnutls_transport_ptr_t) (long) stream->fd, stream);
|
||||||
|
gnutls_transport_set_vec_push_function(gs, &dnstls_stream_writev);
|
||||||
|
|
||||||
|
stream->encrypted = true;
|
||||||
|
stream->dnstls_data.handshake = gnutls_handshake(gs);
|
||||||
|
if (stream->dnstls_data.handshake < 0 && gnutls_error_is_fatal(stream->dnstls_data.handshake))
|
||||||
|
return -ECONNREFUSED;
|
||||||
|
|
||||||
|
stream->dnstls_data.session = TAKE_PTR(gs);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
void dnstls_stream_free(DnsStream *stream) {
|
||||||
|
assert(stream);
|
||||||
|
assert(stream->encrypted);
|
||||||
|
|
||||||
|
if (stream->dnstls_data.session)
|
||||||
|
gnutls_deinit(stream->dnstls_data.session);
|
||||||
|
}
|
||||||
|
|
||||||
|
int dnstls_stream_on_io(DnsStream *stream) {
|
||||||
|
int r;
|
||||||
|
|
||||||
|
assert(stream);
|
||||||
|
assert(stream->encrypted);
|
||||||
|
assert(stream->dnstls_data.session);
|
||||||
|
|
||||||
|
if (stream->dnstls_data.shutdown) {
|
||||||
|
r = gnutls_bye(stream->dnstls_data.session, GNUTLS_SHUT_RDWR);
|
||||||
|
if (r == GNUTLS_E_AGAIN)
|
||||||
|
return -EAGAIN;
|
||||||
|
else if (r < 0)
|
||||||
|
log_debug("Failed to invoke gnutls_bye: %s", gnutls_strerror(r));
|
||||||
|
|
||||||
|
stream->dnstls_data.shutdown = false;
|
||||||
|
dns_stream_unref(stream);
|
||||||
|
return DNSTLS_STREAM_CLOSED;
|
||||||
|
} else if (stream->dnstls_data.handshake < 0) {
|
||||||
|
stream->dnstls_data.handshake = gnutls_handshake(stream->dnstls_data.session);
|
||||||
|
if (stream->dnstls_data.handshake == GNUTLS_E_AGAIN)
|
||||||
|
return -EAGAIN;
|
||||||
|
else if (stream->dnstls_data.handshake < 0) {
|
||||||
|
log_debug("Failed to invoke gnutls_handshake: %s", gnutls_strerror(stream->dnstls_data.handshake));
|
||||||
|
if (gnutls_error_is_fatal(stream->dnstls_data.handshake))
|
||||||
|
return -ECONNREFUSED;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
int dnstls_stream_shutdown(DnsStream *stream, int error) {
|
||||||
|
int r;
|
||||||
|
|
||||||
|
assert(stream);
|
||||||
|
assert(stream->encrypted);
|
||||||
|
assert(stream->dnstls_data.session);
|
||||||
|
|
||||||
|
/* Store TLS Ticket for faster succesive TLS handshakes */
|
||||||
|
if (stream->server && stream->server->dnstls_data.session_data.size == 0 && stream->dnstls_data.handshake == GNUTLS_E_SUCCESS)
|
||||||
|
gnutls_session_get_data2(stream->dnstls_data.session, &stream->server->dnstls_data.session_data);
|
||||||
|
|
||||||
|
if (IN_SET(error, ETIMEDOUT, 0)) {
|
||||||
|
r = gnutls_bye(stream->dnstls_data.session, GNUTLS_SHUT_RDWR);
|
||||||
|
if (r == GNUTLS_E_AGAIN) {
|
||||||
|
if (!stream->dnstls_data.shutdown) {
|
||||||
|
stream->dnstls_data.shutdown = true;
|
||||||
|
dns_stream_ref(stream);
|
||||||
|
return -EAGAIN;
|
||||||
|
}
|
||||||
|
} else if (r < 0)
|
||||||
|
log_debug("Failed to invoke gnutls_bye: %s", gnutls_strerror(r));
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
ssize_t dnstls_stream_write(DnsStream *stream, const char *buf, size_t count) {
|
||||||
|
ssize_t ss;
|
||||||
|
|
||||||
|
assert(stream);
|
||||||
|
assert(stream->encrypted);
|
||||||
|
assert(stream->dnstls_data.session);
|
||||||
|
assert(buf);
|
||||||
|
|
||||||
|
ss = gnutls_record_send(stream->dnstls_data.session, buf, count);
|
||||||
|
if (ss < 0)
|
||||||
|
switch(ss) {
|
||||||
|
case GNUTLS_E_INTERRUPTED:
|
||||||
|
return -EINTR;
|
||||||
|
case GNUTLS_E_AGAIN:
|
||||||
|
return -EAGAIN;
|
||||||
|
default:
|
||||||
|
log_debug("Failed to invoke gnutls_record_send: %s", gnutls_strerror(ss));
|
||||||
|
return -EPIPE;
|
||||||
|
}
|
||||||
|
|
||||||
|
return ss;
|
||||||
|
}
|
||||||
|
|
||||||
|
ssize_t dnstls_stream_read(DnsStream *stream, void *buf, size_t count) {
|
||||||
|
ssize_t ss;
|
||||||
|
|
||||||
|
assert(stream);
|
||||||
|
assert(stream->encrypted);
|
||||||
|
assert(stream->dnstls_data.session);
|
||||||
|
assert(buf);
|
||||||
|
|
||||||
|
ss = gnutls_record_recv(stream->dnstls_data.session, buf, count);
|
||||||
|
if (ss < 0)
|
||||||
|
switch(ss) {
|
||||||
|
case GNUTLS_E_INTERRUPTED:
|
||||||
|
return -EINTR;
|
||||||
|
case GNUTLS_E_AGAIN:
|
||||||
|
return -EAGAIN;
|
||||||
|
default:
|
||||||
|
log_debug("Failed to invoke gnutls_record_recv: %s", gnutls_strerror(ss));
|
||||||
|
return -EPIPE;
|
||||||
|
}
|
||||||
|
|
||||||
|
return ss;
|
||||||
|
}
|
||||||
|
|
||||||
|
void dnstls_server_init(DnsServer *server) {
|
||||||
|
assert(server);
|
||||||
|
|
||||||
|
/* Do not verify cerificate */
|
||||||
|
gnutls_certificate_allocate_credentials(&server->dnstls_data.cert_cred);
|
||||||
|
}
|
||||||
|
|
||||||
|
void dnstls_server_free(DnsServer *server) {
|
||||||
|
assert(server);
|
||||||
|
|
||||||
|
if (server->dnstls_data.cert_cred)
|
||||||
|
gnutls_certificate_free_credentials(server->dnstls_data.cert_cred);
|
||||||
|
|
||||||
|
if (server->dnstls_data.session_data.data)
|
||||||
|
gnutls_free(server->dnstls_data.session_data.data);
|
||||||
|
}
|
21
src/resolve/resolved-dnstls-gnutls.h
Normal file
21
src/resolve/resolved-dnstls-gnutls.h
Normal file
|
@ -0,0 +1,21 @@
|
||||||
|
/* SPDX-License-Identifier: LGPL-2.1+ */
|
||||||
|
#pragma once
|
||||||
|
|
||||||
|
#if !ENABLE_DNS_OVER_TLS || !HAVE_GNUTLS
|
||||||
|
#error This source file requires DNS-over-TLS to be enabled and GnuTLS to be available.
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include <stdbool.h>
|
||||||
|
|
||||||
|
#include <gnutls/gnutls.h>
|
||||||
|
|
||||||
|
struct DnsTlsServerData {
|
||||||
|
gnutls_certificate_credentials_t cert_cred;
|
||||||
|
gnutls_datum_t session_data;
|
||||||
|
};
|
||||||
|
|
||||||
|
struct DnsTlsStreamData {
|
||||||
|
gnutls_session_t session;
|
||||||
|
int handshake;
|
||||||
|
bool shutdown;
|
||||||
|
};
|
28
src/resolve/resolved-dnstls.h
Normal file
28
src/resolve/resolved-dnstls.h
Normal file
|
@ -0,0 +1,28 @@
|
||||||
|
/* SPDX-License-Identifier: LGPL-2.1+ */
|
||||||
|
#pragma once
|
||||||
|
|
||||||
|
#if !ENABLE_DNS_OVER_TLS
|
||||||
|
#error This source file requires DNS-over-TLS to be enabled
|
||||||
|
#endif
|
||||||
|
|
||||||
|
typedef struct DnsTlsServerData DnsTlsServerData;
|
||||||
|
typedef struct DnsTlsStreamData DnsTlsStreamData;
|
||||||
|
|
||||||
|
#if HAVE_GNUTLS
|
||||||
|
#include "resolved-dnstls-gnutls.h"
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include "resolved-dns-stream.h"
|
||||||
|
#include "resolved-dns-transaction.h"
|
||||||
|
|
||||||
|
#define DNSTLS_STREAM_CLOSED 1
|
||||||
|
|
||||||
|
int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server);
|
||||||
|
void dnstls_stream_free(DnsStream *stream);
|
||||||
|
int dnstls_stream_on_io(DnsStream *stream);
|
||||||
|
int dnstls_stream_shutdown(DnsStream *stream, int error);
|
||||||
|
ssize_t dnstls_stream_write(DnsStream *stream, const char *buf, size_t count);
|
||||||
|
ssize_t dnstls_stream_read(DnsStream *stream, void *buf, size_t count);
|
||||||
|
|
||||||
|
void dnstls_server_init(DnsServer *server);
|
||||||
|
void dnstls_server_free(DnsServer *server);
|
Loading…
Reference in a new issue