Add support for rc.conf(5) initialisation.

Provide user support for rc.conf(5) so a user can create a suitable
/etc/rc.conf file to initialise libbsd.

This patch by default adds basic networking support:

 cloned_interfaces
 ifconfig_'interface'
 defaultrouter
 hostname

Refer to FreeBSD documentation for examples.

Users can make a single call to have /etc/rc.conf processed, or pass a
file name to a specific configuration file or a text string with line
feeds can be passed to the scripting version of the interface.

The rc.conf support is implemented in terms of directive handlers that
are called based on a regular expression. The design allows new handlers
to be added as needed.

Line concatenation is still to be implemented.

1 files changed, 303 insertions, 0 deletions

diff --git a/rtemsbsd/rtems/rtems-bsd-rc-conf-net.c b/rtemsbsd/rtems/rtems-bsd-rc-conf-net.c
new file mode 100644
index 00000000..3979e507
--- /dev/null
+++ b/rtemsbsd/rtems/rtems-bsd-rc-conf-net.c
@@ -0,0 +1,303 @@
+/*
+ * Copyright (c) 2016 Chris Johns <chrisj@rtems.org>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Handle the networking directives found in rc.conf.
+ *  - ifconfig_*
+ *  - cloned_interfaces
+ *  - autobridge_interfaces
+ *  - autobridge_bridge*
+ *  - defaultrouter
+ */
+
+#include <rtems/bsd/sys/param.h>
+#include <rtems/bsd/sys/types.h>
+
+#include <sys/queue.h>
+#include <sys/kernel.h>
+#include <sysexits.h>
+
+#include <errno.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <rtems.h>
+#include <rtems/chain.h>
+
+#include <machine/rtems-bsd-commands.h>
+#include <machine/rtems-bsd-rc-conf.h>
+
+/*
+ * cloned_interfaces
+ *
+ * eg cloned_interfaces="vlan0 bridge0 tap1 tap2"
+ *
+ * See 'man rc.conf(5)' on FreeBSD.
+ */
+static int
+cloned_interfaces(rtems_bsd_rc_conf* rc_conf,
+                  int                argc,
+                  const char**       argv)
+{
+  int arg;
+  for (arg = 1; arg < argc; ++arg) {
+    const char* ifconfg_args[] = {
+      "ifconfig", argv[arg], "create", NULL
+    };
+    int r;
+    rtems_bsd_rc_conf_print_cmd(rc_conf, "cloning_interfaces", 3, ifconfg_args);
+    r = rtems_bsd_command_ifconfig(3, (char**) ifconfg_args);
+    if (r != EX_OK) {
+      errno = ECANCELED;
+      return -1;
+    }
+  }
+  return 0;
+}
+
+/*
+ * create_args_'interface'
+ *
+ * eg create_args_myvlan="vlan 102"
+ *
+ * See 'man rc.conf(5)' on FreeBSD.
+ */
+typedef struct {
+  rtems_chain_node node;
+  const char*      label;
+  int              argc;
+  const char**     argv;
+} create_args_item;
+
+static RTEMS_CHAIN_DEFINE_EMPTY(create_args_items);
+
+static int
+create_args_(rtems_bsd_rc_conf* rc_conf,
+             int                argc,
+             const char**       argv)
+{
+  rtems_chain_node*       node = rtems_chain_first(&create_args_items);
+  const rtems_chain_node* tail = rtems_chain_tail(&create_args_items);
+  const char*             label = argv[0] + strlen("create_args_");
+  create_args_item*       item;
+  int                     arg;
+
+  while (node != tail) {
+    item = (create_args_item*) node;
+    if (strcasecmp(item->label, label) == 0) {
+      fprintf(stderr, "error: %s:%d: duplicate create args entry: %s\n",
+              rtems_bsd_rc_conf_name(rc_conf),
+              rtems_bsd_rc_conf_line(rc_conf),
+              argv[0]);
+      errno = EEXIST;
+      return -1;
+    }
+    node = rtems_chain_next(node);
+  }
+
+  item = calloc(1, sizeof(*item));
+  if (item == NULL) {
+    errno = ENOMEM;
+    fprintf(stderr, "error: %s:%d: %s\n",
+            rtems_bsd_rc_conf_name(rc_conf),
+            rtems_bsd_rc_conf_line(rc_conf),
+            strerror(errno));
+    return -1;
+  }
+
+  item->argc = argc;
+
+  item->label = strdup(label);
+  if (item->label == NULL) {
+    free(item);
+    errno = ENOMEM;
+    fprintf(stderr, "error: %s:%d: %s\n",
+            rtems_bsd_rc_conf_name(rc_conf),
+            rtems_bsd_rc_conf_line(rc_conf),
+            strerror(errno));
+    return -1;
+  }
+
+  item->argv = calloc(argc + 1, sizeof(char*));
+  if (item->argv == NULL) {
+    free((void*) item->label);
+    free(item);
+    errno = ENOMEM;
+    fprintf(stderr, "error: %s:%d: %s\n",
+            rtems_bsd_rc_conf_name(rc_conf),
+            rtems_bsd_rc_conf_line(rc_conf),
+            strerror(errno));
+    return -1;
+  }
+
+  for (arg = 0; arg < argc; ++arg) {
+    item->argv[arg] = strdup(argv[0]);
+    if (item->argv[arg] == NULL) {
+      int a;
+      for (a = 0; a < arg; ++a)
+        free((void*) item->argv[a]);
+      free(item->argv);
+      free((void*) item->label);
+      free(item);
+      errno = ENOMEM;
+      fprintf(stderr, "error: %s:%d: %s\n",
+              rtems_bsd_rc_conf_name(rc_conf),
+              rtems_bsd_rc_conf_line(rc_conf),
+              strerror(errno));
+      return -1;
+    }
+  }
+
+  rtems_chain_append(&create_args_items, &item->node);
+
+  return 0;
+}
+
+/*
+ * ifconfig_'interface'
+ *
+ * eg ifconfig_em0="inet 10.10.5.33 netmask 255.255.255.0"
+ *
+ * See 'man rc.conf(5)' on FreeBSD.
+ */
+static int
+ifconfig_(rtems_bsd_rc_conf* rc_conf,
+          int                argc,
+          const char**       argv)
+{
+  const char** args;
+  int          arg;
+  int          r;
+
+  for (arg = 1; arg < argc; ++arg) {
+    if (strcasecmp(argv[arg], "NOAUTO") == 0)
+      return 0;
+  }
+
+  args = calloc(argc + 3, sizeof(char*));
+  if (args == NULL) {
+    errno = ENOMEM;
+    return -1;
+  }
+
+  args[0] = "ifconfig";
+  args[1] = argv[0] + strlen("ifconfig_");
+
+  for (arg = 1; arg < argc; ++arg)
+    args[arg + 1] = argv[arg];
+
+  args[argc + 1] = "up";
+
+  rtems_bsd_rc_conf_print_cmd(rc_conf, "ifconfig", argc + 2, args);
+
+  r = rtems_bsd_command_ifconfig(argc + 2, (char**) args);
+
+  free(args);
+
+  if (r != EX_OK) {
+    errno = ECANCELED;
+    return -1;
+  }
+
+  return 0;
+}
+
+/*
+ * hostname
+ *
+ * eg hostname="myhost"
+ *
+ * See 'man rc.conf(5)' on FreeBSD.
+ */
+static int
+hostname(rtems_bsd_rc_conf* rc_conf,
+         int                argc,
+         const char**       argv)
+{
+  if (argc > 2) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  rtems_bsd_rc_conf_print_cmd(rc_conf, "hostname", argc, argv);
+
+  return sethostname(argv[1], strlen(argv[1]));
+}
+
+/*
+ * defaultrouter
+ *
+ * eg defaultrouter="1.2.3.4"
+ *
+ * See 'man rc.conf(5)' on FreeBSD.
+ */
+static int
+defaultrouter(rtems_bsd_rc_conf* rc_conf,
+              int                argc,
+              const char**       argv)
+{
+  if (argc > 2) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  if (strcasecmp(argv[1], "NO") != 0) {
+    const char* args[] = {
+      "route", "add", "default", argv[1], NULL
+    };
+    int r;
+
+    rtems_bsd_rc_conf_print_cmd(rc_conf, "defaultrouter", 4, args);
+
+    r = rtems_bsd_command_route(4, (char**) args);
+    if (r != EX_OK) {
+      errno = ECANCELED;
+      return -1;
+    }
+  }
+
+  return 0;
+}
+
+static void
+add_directive(const char* name, rtems_bsd_rc_conf_directive handler)
+{
+  int r;
+  r = rtems_bsd_rc_conf_directive_add(name, handler);
+  if (r < 0)
+    fprintf(stderr, "error: cannot register rc.conf handler: %s\n", name);
+}
+
+void
+rc_conf_net_init(void* arg)
+{
+  add_directive("cloned_interfaces", cloned_interfaces);
+  add_directive("create_args_.*", create_args_);
+  add_directive("ifconfig_*", ifconfig_);
+  add_directive("hostname", hostname);
+  add_directive("defaultrouter", defaultrouter);
+}