X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/tripe/blobdiff_plain/d98625f4404ba4fca4f395bc72f15d68043d75b4..7737eb87d283d46b7a90caba20ac75c3214451d3:/server/admin.c

diff --git a/server/admin.c b/server/admin.c
index 0ec187ce..acdb973a 100644
--- a/server/admin.c
+++ b/server/admin.c
@@ -61,10 +61,14 @@ static const trace_opt w_opts[] = {
 
 /*----- Static variables --------------------------------------------------*/
 
+#ifdef HAVE_LIBADNS
+  static adns_state ads;
+  sel_hook hook;
+#endif
 static admin *admins;
 static admin *a_dead;
 static sel_file sock;
-static const char *sockname;
+static const char *sockname = 0;
 static sym_table a_svcs;
 static unsigned flags = 0;
 static admin *a_stdin = 0;
@@ -272,14 +276,19 @@ void a_vformat(dstr *d, const char *fmt, va_list *ap)
     } else if (*fmt == '?') {
       if (strcmp(fmt, "?ADDR") == 0) {
 	const addr *a = va_arg(*ap, const addr *);
-	switch (a->sa.sa_family) {
-	  case AF_INET:
-	    u_quotify(d, "INET");
-	    u_quotify(d, inet_ntoa(a->sin.sin_addr));
-	    dstr_putf(d, " %u", (unsigned)ntohs(a->sin.sin_port));
-	    break;
-	  default:
-	    abort();
+	char name[NI_MAXHOST], serv[NI_MAXSERV];
+	int ix, err;
+	if ((err = getnameinfo(&a->sa, addrsz(a),
+			       name, sizeof(name), serv, sizeof(serv),
+			       (NI_NUMERICHOST | NI_NUMERICSERV |
+				NI_DGRAM)))) {
+	  dstr_putf(d, " E%d", err);
+	  u_quotify(d, gai_strerror(err));
+	} else {
+	  ix = afix(a->sa.sa_family); assert(ix >= 0);
+	  u_quotify(d, aftab[ix].name);
+	  u_quotify(d, name);
+	  u_quotify(d, serv);
 	}
       } else if (strcmp(fmt, "?B64") == 0) {
 	const octet *p = va_arg(*ap, const octet *);
@@ -550,8 +559,8 @@ void a_notify(const char *fmt, ...)
 void a_quit(void)
 {
   close(sock.fd);
-  unlink(sockname);
-  FOREACH_PEER(p, { p_destroy(p); });
+  if (sockname) unlink(sockname);
+  FOREACH_PEER(p, { p_destroy(p, 1); });
   ps_quit();
   exit(0);
 }
@@ -1006,6 +1015,101 @@ static void a_svcrelease(admin_service *svc)
 
 /*----- Name resolution operations ----------------------------------------*/
 
+#ifdef HAVE_LIBADNS
+
+/* --- @before_select@ --- *
+ *
+ * Arguments:	@sel_state *s@ = the @sel@ multiplexor (unused)
+ *		@sel_args *a@ = input to @select@, to be updated
+ *		@void *p@ = a context pointer (unused)
+ *
+ * Returns:	---
+ *
+ * Use:		An I/O multiplexor hook, called just before waiting for I/O
+ *		events.
+ *
+ *		Currently its main purpose is to wire ADNS into the event
+ *		loop.
+ */
+
+static void before_select(sel_state *s, sel_args *a, void *p)
+{
+  struct timeval now;
+  adns_query q;
+  adns_answer *n;
+  admin_resop *r;
+  int any = 0;
+
+  /* --- Check for name-resolution progress --- *
+   *
+   * If there is any, then clobber the timeout: one of the resolver
+   * callbacks might have renewed its interest in a file descriptor, but too
+   * late to affect this @select@ call.
+   *
+   * I think, strictly, this is an mLib bug, but it's cheap enough to hack
+   * around here.  Fixing it will wait for mLib 3.
+   */
+
+  for (;;) {
+    q = 0;
+    if (adns_check(ads, &q, &n, &p)) break;
+    r = p;
+    any = 1;
+    if (n->status != adns_s_ok) {
+      T( trace(T_ADMIN, "admin: resop %s failed: %s",
+	       BGTAG(r), adns_strerror(n->status)); )
+      a_bgfail(&r->bg, "resolve-error", "%s", r->addr, A_END);
+      r->func(r, ARES_FAIL);
+    } else {
+      T( trace(T_ADMIN, "admin: resop %s ok", BGTAG(r)); )
+      assert(n->type == adns_r_addr);
+      assert(n->nrrs > 0);
+      assert(n->rrs.addr[0].len <= sizeof(r->sa));
+      memcpy(&r->sa, &n->rrs.addr[0].addr, n->rrs.addr[0].len);
+      setport(&r->sa, r->port);
+      r->func(r, ARES_OK);
+    }
+    free(n);
+    sel_rmtimer(&r->t);
+    xfree(r->addr);
+    a_bgrelease(&r->bg);
+  }
+
+  if (any) { a->tvp = &a->tv; a->tv.tv_sec = 0; a->tv.tv_usec = 0; }
+
+  gettimeofday(&now, 0);
+  adns_beforeselect(ads, &a->maxfd,
+		    &a->fd[SEL_READ], &a->fd[SEL_WRITE], &a->fd[SEL_EXC],
+		    &a->tvp, &a->tv, &now);
+}
+
+/* --- @after_select@ --- *
+ *
+ * Arguments:	@sel_state *s@ = the @sel@ multiplexor (unused)
+ *		@sel_args *a@ = input to @select@, to be updated
+ *		@void *p@ = a context pointer (unused)
+ *
+ * Returns:	---
+ *
+ * Use:		An I/O multiplexor hook, called just after waiting for I/O
+ *		events.
+ *
+ *		Currently its main purpose is to wire ADNS into the event
+ *		loop.
+ */
+
+static void after_select(sel_state *s, sel_args *a, void *p)
+{
+  struct timeval now;
+
+  gettimeofday(&now, 0);
+  adns_afterselect(ads, a->maxfd,
+		   &a->fd[SEL_READ], &a->fd[SEL_WRITE], &a->fd[SEL_EXC],
+		   &now);
+}
+
+#else
+
 /* --- @a_resolved@ --- *
  *
  * Arguments:	@struct hostent *h@ = pointer to resolved hostname
@@ -1038,6 +1142,8 @@ static void a_resolved(struct hostent *h, void *v)
   a_bgrelease(&r->bg);
 }
 
+#endif
+
 /* --- @a_restimer@ --- *
  *
  * Arguments:	@struct timeval *tv@ = timer
@@ -1055,7 +1161,11 @@ static void a_restimer(struct timeval *tv, void *v)
   T( trace(T_ADMIN, "admin: resop %s timeout", BGTAG(r)); )
   a_bgfail(&r->bg, "resolver-timeout", "%s", r->addr, A_END);
   r->func(r, ARES_FAIL);
+#ifdef HAVE_LIBADNS
+  adns_cancel(r->q);
+#else
   bres_abort(&r->r);
+#endif
   xfree(r->addr);
   a_bgrelease(&r->bg);
 }
@@ -1077,7 +1187,11 @@ static void a_rescancel(admin_bgop *bg)
   r->func(r, ARES_FAIL);
   sel_rmtimer(&r->t);
   xfree(r->addr);
+#ifdef HAVE_LIBADNS
+  adns_cancel(r->q);
+#else
   bres_abort(&r->r);
+#endif
 }
 
 /* --- @a_resolve@ --- *
@@ -1100,17 +1214,37 @@ static void a_resolve(admin *a, admin_resop *r, const char *tag,
 {
   struct timeval tv;
   unsigned long pt;
+  int af = AF_UNSPEC;
+  const char *fam = "ANY";
   char *p;
-  int i = 0;
+  int i = 0, j;
+  struct addrinfo *ai, *ailist, aihint = { 0 };
+#ifdef HAVE_LIBADNS
+  int err;
+  adns_queryflags qf;
+#endif
 
   /* --- Fill in the easy bits of address --- */
 
   r->bg.tag = "<starting>";
   r->addr = 0;
   r->func = func;
-  if (mystrieq(av[i], "inet")) i++;
+  if (mystrieq(av[i], "any"))
+    { fam = "ANY"; af = AF_UNSPEC; i++; }
+  else for (j = 0; j < NADDRFAM; j++) {
+    if (mystrieq(av[i], aftab[j].name)) {
+      if (udpsock[j].sf.fd < 0) {
+	a_fail(a, "disabled-address-family", "%s", aftab[j].name, A_END);
+	goto fail;
+      }
+      fam = aftab[j].name;
+      af = aftab[j].af;
+      i++;
+      break;
+    }
+  }
   if (ac - i != 1 && ac - i != 2) {
-    a_fail(a, "bad-addr-syntax", "[inet] ADDRESS [PORT]", A_END);
+    a_fail(a, "bad-addr-syntax", "[FAMILY] ADDRESS [PORT]", A_END);
     goto fail;
   }
   r->addr = xstrdup(av[i]);
@@ -1141,16 +1275,33 @@ static void a_resolve(admin *a, admin_resop *r, const char *tag,
 
   if (a_bgadd(a, &r->bg, tag, a_rescancel))
     goto fail;
-  T( trace(T_ADMIN, "admin: %u, resop %s, hostname `%s'",
-	   a->seq, BGTAG(r), r->addr); )
+  T( trace(T_ADMIN, "admin: %u, resop %s, hostname `%s', family `%s'",
+	   a->seq, BGTAG(r), r->addr, fam); )
 
   /* --- If the name is numeric, do it the easy way --- */
 
-  if (inet_aton(av[i], &r->sa.sin.sin_addr)) {
-    T( trace(T_ADMIN, "admin: resop %s done the easy way", BGTAG(r)); )
-    r->sa.sin.sin_family = AF_INET;
-    setport(&r->sa, r->port);
-    func(r, ARES_OK);
+  aihint.ai_family = af;
+  aihint.ai_socktype = SOCK_DGRAM;
+  aihint.ai_protocol = IPPROTO_UDP;
+  aihint.ai_flags = AI_NUMERICHOST;
+  if (!getaddrinfo(av[i], 0, &aihint, &ailist)) {
+    for (ai = ailist; ai; ai = ai->ai_next) {
+      if ((j = afix(ai->ai_family)) >= 0 && udpsock[j].sf.fd >= 0)
+	break;
+    }
+    if (!ai) {
+      T( trace(T_ADMIN, "admin: resop %s failed: "
+	       "no suitable addresses returned", BGTAG(r)); )
+      a_bgfail(&r->bg, "resolve-error", "%s" , r->addr, A_END);
+      func(r, ARES_FAIL);
+    } else {
+      T( trace(T_ADMIN, "admin: resop %s done the easy way", BGTAG(r)); )
+      assert(ai->ai_addrlen <= sizeof(r->sa));
+      memcpy(&r->sa, ai->ai_addr, ai->ai_addrlen);
+      setport(&r->sa, r->port);
+      func(r, ARES_OK);
+    }
+    freeaddrinfo(ailist);
     xfree(r->addr);
     a_bgrelease(&r->bg);
     return;
@@ -1161,13 +1312,43 @@ static void a_resolve(admin *a, admin_resop *r, const char *tag,
   gettimeofday(&tv, 0);
   tv.tv_sec += T_RESOLVE;
   sel_addtimer(&sel, &r->t, &tv, a_restimer, r);
+#ifdef HAVE_LIBADNS
+  qf = adns_qf_search;
+  for (j = 0; j < NADDRFAM; j++) {
+    if ((af == AF_UNSPEC || af == aftab[i].af) && udpsock[j].sf.fd >= 0)
+      qf |= aftab[j].qf;
+  }
+  if ((err = adns_submit(ads, r->addr, adns_r_addr, qf, r, &r->q)) != 0) {
+    T( trace(T_ADMIN, "admin: resop %s adns_submit failed: %s",
+	     BGTAG(r), strerror(err)); )
+    a_bgfail(&r->bg, "resolve-error", "%s", r->addr, A_END);
+    goto fail_release;
+  }
+#else
+  if (af != AF_UNSPEC && af != AF_INET) {
+    T( trace(T_ADMIN, "admin: resop %s failed: unsupported address family",
+	     BGTAG(r)); )
+    a_bgfail(&r->bg, "resolve-error", "%s", r->addr, A_END);
+    goto fail_release;
+  }
+  if (udpsock[AFIX_INET].sf.fd < 0) {
+    a_bgfail(&r->bg, "disabled-address-family", "INET", A_END);
+    goto fail_release;
+  }
   bres_byname(&r->r, r->addr, a_resolved, r);
+#endif
   return;
 
 fail:
   func(r, ARES_FAIL);
   if (r->addr) xfree(r->addr);
   xfree(r);
+  return;
+
+fail_release:
+  func(r, ARES_FAIL);
+  xfree(r->addr);
+  a_bgrelease(&r->bg);
 }
 
 /*----- Option parsing ----------------------------------------------------*/
@@ -1240,6 +1421,7 @@ static void a_doadd(admin_resop *r, int rc)
 
   if (add->peer.tag) xfree(add->peer.tag);
   if (add->peer.privtag) xfree(add->peer.privtag);
+  if (add->peer.knock) xfree(add->peer.knock);
   xfree(add->peer.name);
 }
 
@@ -1265,6 +1447,7 @@ static void acmd_add(admin *a, unsigned ac, char *av[])
   add->peer.name = 0;
   add->peer.tag = 0;
   add->peer.privtag = 0;
+  add->peer.knock = 0;
   add->peer.t_ka = 0;
   add->peer.tops = tun_default;
   add->peer.f = 0;
@@ -1288,15 +1471,21 @@ static void acmd_add(admin *a, unsigned ac, char *av[])
     })
     OPTTIME("-keepalive", t, { add->peer.t_ka = t; })
     OPT("-cork", { add->peer.f |= KXF_CORK; })
+    OPT("-ephemeral", { add->peer.f |= PSF_EPHEM; })
     OPTARG("-key", arg, {
       if (add->peer.tag) xfree(add->peer.tag);
       add->peer.tag = xstrdup(arg);
     })
-    OPT("-mobile", { add->peer.f |= PSF_MOBILE; })
+    OPT("-mobile", { add->peer.f |= PSF_MOBILE | PSF_EPHEM; })
     OPTARG("-priv", arg, {
       if (add->peer.privtag) xfree(add->peer.privtag);
       add->peer.privtag = xstrdup(arg);
     })
+    OPTARG("-knock", arg, {
+      if (add->peer.knock) xfree(add->peer.knock);
+      add->peer.knock = xstrdup(arg);
+      add->peer.f |= PSF_EPHEM;
+    })
   });
 
   /* --- Make sure someone's not got there already --- */
@@ -1323,6 +1512,7 @@ fail:
   if (add->peer.name) xfree(add->peer.name);
   if (add->peer.tag) xfree(add->peer.tag);
   if (add->peer.privtag) xfree(add->peer.privtag);
+  if (add->peer.knock) xfree(add->peer.knock);
   xfree(add);
   return;
 }
@@ -1680,13 +1870,16 @@ static void acmd_port(admin *a, unsigned ac, char *av[])
     a_fail(a, "unknown-address-family", "%s", av[0], A_END);
     return;
   found:
-    assert(udpsock[i].fd >= 0);
+    if (udpsock[i].sf.fd < 0) {
+      a_fail(a, "disabled-address-family", "%s", aftab[i].name, A_END);
+      return;
+    }
   } else {
     for (i = 0; i < NADDRFAM; i++)
-      if (udpsock[i].fd >= 0) goto found;
+      if (udpsock[i].sf.fd >= 0) goto found;
     abort();
   }
-  a_info(a, "%u", p_port(i), A_END);
+  a_info(a, "%u", udpsock[i].port, A_END);
   a_ok(a);
 }
 
@@ -1798,7 +1991,7 @@ static void acmd_getchal(admin *a, unsigned ac, char *av[])
   buf b;
 
   buf_init(&b, buf_i, PKBUFSZ);
-  c_new(&b);
+  c_new(0, 0, &b);
   a_info(a, "?B64", BBASE(&b), (size_t)BLEN(&b), A_END);
   a_ok(a);
 }
@@ -1815,7 +2008,7 @@ static void acmd_checkchal(admin *a, unsigned ac, char *av[])
     a_fail(a, "bad-base64", "%s", codec_strerror(err), A_END);
   else {
     buf_init(&b, d.buf, d.len);
-    if (c_check(&b) || BBAD(&b) || BLEFT(&b))
+    if (c_check(0, 0, &b) || BBAD(&b) || BLEFT(&b))
       a_fail(a, "invalid-challenge", A_END);
     else
       a_ok(a);
@@ -1865,6 +2058,7 @@ static void acmd_peerinfo(admin *a, unsigned ac, char *av[])
   if ((p = a_findpeer(a, av[0])) != 0) {
     ps = p_spec(p);
     a_info(a, "tunnel=%s", ps->tops->name, A_END);
+    if (ps->knock) a_info(a, "knock=%s", ps->knock, A_END);
     a_info(a, "key=%s", p_tag(p),
 	   "current-key=%s", p->kx.kpub->tag, A_END);
     if ((ptag = p_privtag(p)) == 0) ptag = "(default)";
@@ -1873,6 +2067,7 @@ static void acmd_peerinfo(admin *a, unsigned ac, char *av[])
     a_info(a, "keepalive=%lu", ps->t_ka, A_END);
     a_info(a, "corked=%s", BOOL(p->kx.f&KXF_CORK),
 	   "mobile=%s", BOOL(ps->f&PSF_MOBILE),
+	   "ephemeral=%s", BOOL(ps->f&PSF_EPHEM),
 	   A_END);
     a_ok(a);
   }
@@ -1928,7 +2123,7 @@ static void acmd_kill(admin *a, unsigned ac, char *av[])
   peer *p;
 
   if ((p = a_findpeer(a, av[0])) != 0) {
-    p_destroy(p);
+    p_destroy(p, 1);
     a_ok(a);
   }
 }
@@ -2209,7 +2404,10 @@ static void a_line(char *p, size_t len, void *vp)
  *
  * Returns:	---
  *
- * Use:		Creates a new admin connection.
+ * Use:		Creates a new admin connection.  It's safe to call this
+ *		before @a_init@ -- and, indeed, this makes sense if you also
+ *		call @a_switcherr@ to report initialization errors through
+ *		the administration machinery.
  */
 
 void a_create(int fd_in, int fd_out, unsigned f)
@@ -2287,7 +2485,7 @@ void a_preselect(void) { if (a_dead) a_destroypending(); }
 
 void a_daemon(void) { flags |= F_DAEMON; }
 
-/* --- @a_init@ --- *
+/* --- @a_listen@ --- *
  *
  * Arguments:	@const char *name@ = socket name to create
  *		@uid_t u@ = user to own the socket
@@ -2299,19 +2497,14 @@ void a_daemon(void) { flags |= F_DAEMON; }
  * Use:		Creates the admin listening socket.
  */
 
-void a_init(const char *name, uid_t u, gid_t g, mode_t m)
+void a_listen(const char *name, uid_t u, gid_t g, mode_t m)
 {
   int fd;
   int n = 5;
   struct sockaddr_un sun;
-  struct sigaction sa;
   size_t sz;
   mode_t omask;
 
-  /* --- Create services table --- */
-
-  sym_create(&a_svcs);
-
   /* --- Set up the socket address --- */
 
   sz = strlen(name) + 1;
@@ -2373,12 +2566,43 @@ again:
   sel_initfile(&sel, &sock, fd, SEL_READ, a_accept, 0);
   sel_addfile(&sock);
   sockname = name;
-  bres_init(&sel);
+}
+
+/* --- @a_switcherr@ --- *
+ *
+ * Arguments:	---
+ *
+ * Returns:	---
+ *
+ * Use:		Arrange to report warnings, trace messages, etc. to
+ *		administration clients rather than the standard-error stream.
+ *
+ *		Obviously this makes no sense unless there is at least one
+ *		client established.  Calling @a_listen@ won't help with this,
+ *		because the earliest a new client can connect is during the
+ *		first select-loop iteration, which is too late: some initial
+ *		client must have been added manually using @a_create@.
+ */
+
+void a_switcherr(void)
+{
   T( trace_custom(a_trace, 0);
      trace(T_ADMIN, "admin: enabled custom tracing"); )
   flags |= F_INIT;
+}
+
+/* --- @a_signals@ --- *
+ *
+ * Arguments:	---
+ *
+ * Returns:	---
+ *
+ * Use:		Establishes handlers for the obvious signals.
+ */
 
-  /* --- Set up signal handlers --- */
+void a_signals(void)
+{
+  struct sigaction sa;
 
   sig_add(&s_term, SIGTERM, a_sigdie, 0);
   sig_add(&s_hup, SIGHUP, a_sighup, 0);
@@ -2387,4 +2611,38 @@ again:
     sig_add(&s_int, SIGINT, a_sigdie, 0);
 }
 
+/* --- @a_init@ --- *
+ *
+ * Arguments:	---
+ *
+ * Returns:	---
+ *
+ * Use:		Creates the admin listening socket.
+ */
+
+void a_init(void)
+{
+#ifdef HAVE_LIBADNS
+  int err;
+#endif
+
+  /* --- Create services table --- */
+
+  sym_create(&a_svcs);
+
+  /* --- Prepare the background name resolver --- */
+
+#ifdef HAVE_LIBADNS
+  if ((err = adns_init(&ads,
+		       (adns_if_permit_ipv4 | adns_if_permit_ipv6 |
+			adns_if_noserverwarn | adns_if_nosigpipe |
+			adns_if_noautosys),
+		       0)) != 0)
+    die(EXIT_FAILURE, "failed to initialize ADNS: %s", strerror(errno));
+  sel_addhook(&sel, &hook, before_select, after_select, 0);
+#else
+  bres_init(&sel);
+#endif
+}
+
 /*----- That's all, folks -------------------------------------------------*/