Re-try to open DNSSEC trust anchor file if /var is not mounted yet.

This is a step towards starting unwind earlier, before the network is
up and partitions are mounted.
OK kn

diff --git a/sbin/unwind/frontend.c b/sbin/unwind/frontend.c
index 18d91df..603aced 100644 (file)
--- a/sbin/unwind/frontend.c
+++ b/sbin/unwind/frontend.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: frontend.c,v 1.66 2021/01/27 08:30:50 florian Exp $   */
+/*     $OpenBSD: frontend.c,v 1.67 2021/01/30 10:31:51 florian Exp $   */
 
 /*
  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
@@ -258,8 +258,6 @@ frontend(int debug, int verbose)
        TAILQ_INIT(&trust_anchors);
        TAILQ_INIT(&new_trust_anchors);
 
-       add_new_ta(&trust_anchors, KSK2017);
-
        event_dispatch();
 
        frontend_shutdown();
@@ -448,10 +446,21 @@ frontend_dispatch_main(int fd, short event, void *bula)
                        control_listen(fd);
                        break;
                case IMSG_TAFD:
-                       if ((ta_fd = imsg.fd) != -1)
+                       if ((ta_fd = imsg.fd) == -1)
+                               fatalx("%s: expected to receive imsg trust "
+                                   "anchor fd but didn't receive any",
+                                   __func__);
+                       if (TAILQ_EMPTY(&trust_anchors)) {
+                               /*
+                                * We did not receive a trustanchor from DNS,
+                                * maybe the built-in one is out of date, try
+                                * with the one from disk.
+                                */
                                parse_trust_anchor(&trust_anchors, ta_fd);
-                       if (!TAILQ_EMPTY(&trust_anchors))
-                               send_trust_anchors(&trust_anchors);
+                               if (!TAILQ_EMPTY(&trust_anchors))
+                                       send_trust_anchors(&trust_anchors);
+                       } else
+                               write_trust_anchors(&trust_anchors, ta_fd);
                        break;
                case IMSG_BLFD:
                        if ((fd = imsg.fd) == -1)

diff --git a/sbin/unwind/resolver.c b/sbin/unwind/resolver.c
index a9c120e..d931321 100644 (file)
--- a/sbin/unwind/resolver.c
+++ b/sbin/unwind/resolver.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: resolver.c,v 1.139 2021/01/29 17:48:58 florian Exp $  */
+/*     $OpenBSD: resolver.c,v 1.140 2021/01/30 10:31:51 florian Exp $  */
 
 /*
  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
@@ -423,6 +423,8 @@ resolver(int debug, int verbose)
        TAILQ_INIT(&new_trust_anchors);
        TAILQ_INIT(&running_queries);
 
+       add_new_ta(&trust_anchors, KSK2017);
+
        event_dispatch();
 
        resolver_shutdown();

diff --git a/sbin/unwind/unwind.c b/sbin/unwind/unwind.c
index 178d2d8..93c5c03 100644 (file)
--- a/sbin/unwind/unwind.c
+++ b/sbin/unwind/unwind.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: unwind.c,v 1.58 2021/01/29 17:46:04 florian Exp $     */
+/*     $OpenBSD: unwind.c,v 1.59 2021/01/30 10:31:52 florian Exp $     */
 
 /*
  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
@@ -49,6 +49,8 @@
 #include "control.h"
 
 #define        TRUST_ANCHOR_FILE       "/var/db/unwind.key"
+#define        WAIT_TA_FD_TIMEOUT      5
+#define        WAIT_TA_FD_MAX_RETRY    3
 
 enum uw_process {
        PROC_MAIN,
@@ -74,6 +76,8 @@ int           main_sendall(enum imsg_type, void *, uint16_t);
 void           open_ports(void);
 void           solicit_dns_proposals(void);
 void           send_blocklist_fd(void);
+void           open_trustanchor(void);
+void           open_trustanchor_timeout(int, short, void *);
 
 struct uw_conf         *main_conf;
 static struct imsgev   *iev_frontend;
@@ -83,6 +87,7 @@ pid_t                  frontend_pid;
 pid_t                   resolver_pid;
 uint32_t                cmd_opts;
 int                     routesock;
+struct event            ta_timo_ev;
 
 void
 main_sig_handler(int sig, short event, void *arg)
@@ -125,7 +130,7 @@ main(int argc, char *argv[])
        int              ch, debug = 0, resolver_flag = 0, frontend_flag = 0;
        int              frontend_routesock, rtfilter;
        int              pipe_main2frontend[2], pipe_main2resolver[2];
-       int              control_fd, ta_fd;
+       int              control_fd;
        char            *csock, *saved_argv0;
 
        csock = UNWIND_SOCKET;
@@ -280,12 +285,6 @@ main(int argc, char *argv[])
                fatal("route socket");
        shutdown(SHUT_RD, routesock);
 
-       if ((ta_fd = open(TRUST_ANCHOR_FILE, O_RDWR | O_CREAT, 0644)) == -1)
-               log_warn("%s", TRUST_ANCHOR_FILE);
-
-       /* receiver handles failed open correctly */
-       main_imsg_compose_frontend_fd(IMSG_TAFD, 0, ta_fd);
-
        main_imsg_compose_frontend_fd(IMSG_CONTROLFD, 0, control_fd);
        main_imsg_compose_frontend_fd(IMSG_ROUTESOCK, 0, frontend_routesock);
        main_imsg_send_config(main_conf);
@@ -293,9 +292,17 @@ main(int argc, char *argv[])
        if (main_conf->blocklist_file != NULL)
                send_blocklist_fd();
 
-       if (pledge("stdio rpath sendfd", NULL) == -1)
+       /* this is the best we can do, when we startup /var is not mounted */
+       if (unveil("/var", "rwc") == -1)
+               fatal("unveil");
+       if (unveil("/", "r") == -1)
+               fatal("unveil");
+       if (pledge("stdio rpath wpath cpath sendfd", NULL) == -1)
                fatal("pledge");
 
+       evtimer_set(&ta_timo_ev, open_trustanchor_timeout, NULL);
+       open_trustanchor();
+
        main_imsg_compose_frontend(IMSG_STARTUP, 0, NULL, 0);
        main_imsg_compose_resolver(IMSG_STARTUP, 0, NULL, 0);
 
@@ -959,3 +966,31 @@ imsg_receive_config(struct imsg *imsg, struct uw_conf **xconf)
                break;
        }
 }
+
+void
+open_trustanchor(void)
+{
+       static int                       retry;
+       static const struct timeval      timeout = { WAIT_TA_FD_TIMEOUT, 0};
+       int                              fd;
+
+       fd = open(TRUST_ANCHOR_FILE, O_RDWR | O_CREAT, 0644);
+
+       if (fd != -1)
+               main_imsg_compose_frontend_fd(IMSG_TAFD, 0, fd);
+       else if (retry++ < WAIT_TA_FD_MAX_RETRY) {
+               /* /var is not mounted yet, try a bit later */
+               evtimer_add(&ta_timo_ev, &timeout);
+               return;
+       } else
+               log_warn("giving up on %s", TRUST_ANCHOR_FILE);
+
+       if (pledge("stdio rpath sendfd", NULL) == -1)
+               fatal("pledge");
+}
+
+void
+open_trustanchor_timeout(int fd, short events, void *arg)
+{
+       open_trustanchor();
+}