Merge tag 'upstream/2.3_rc1'

Upstream version 2.3_rc1

1 files changed, 717 insertions, 0 deletions

diff --git a/src/openvpn/pf.c b/src/openvpn/pf.c
new file mode 100644
index 0000000..3c46801
--- /dev/null
+++ b/src/openvpn/pf.c
@@ -0,0 +1,717 @@
+/*
+ *  OpenVPN -- An application to securely tunnel IP networks
+ *             over a single TCP/UDP port, with support for SSL/TLS-based
+ *             session authentication and key exchange,
+ *             packet encryption, packet authentication, and
+ *             packet compression.
+ *
+ *  Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program (see the file COPYING included with this
+ *  distribution); if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/* packet filter functions */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#elif defined(_MSC_VER)
+#include "config-msvc.h"
+#endif
+
+#include "syshead.h"
+
+#if defined(ENABLE_PF)
+
+#include "init.h"
+
+#include "memdbg.h"
+
+#include "pf-inline.h"
+
+static void
+pf_destroy (struct pf_set *pfs)
+{
+  if (pfs)
+    {
+      if (pfs->cns.hash_table)
+	hash_free (pfs->cns.hash_table);
+
+      {
+	struct pf_cn_elem *l = pfs->cns.list;
+	while (l)
+	  {
+	    struct pf_cn_elem *next = l->next;
+	    free (l->rule.cn);
+	    free (l);
+	    l = next;
+	  }
+      }
+      {
+	struct pf_subnet *l = pfs->sns.list;
+	while (l)
+	  {
+	    struct pf_subnet *next = l->next;
+	    free (l);
+	    l = next;
+	  }
+      }
+      free (pfs);
+    }
+}
+
+static bool
+add_client (const char *line, const char *prefix, const int line_num, struct pf_cn_elem ***next, const bool exclude)
+{
+  struct pf_cn_elem *e;
+  ALLOC_OBJ_CLEAR (e, struct pf_cn_elem);
+  e->rule.exclude = exclude;
+  e->rule.cn = string_alloc (line, NULL);
+  **next = e;
+  *next = &e->next;
+  return true;
+}
+
+static bool
+add_subnet (const char *line, const char *prefix, const int line_num, struct pf_subnet ***next, const bool exclude)
+{
+  struct in_addr network;
+  in_addr_t netmask = 0;
+
+  if (strcmp (line, "unknown"))
+    {
+      int netbits = 32;
+      char *div = strchr (line, '/');
+
+      if (div)
+	{
+	  *div++ = '\0';
+	  if (sscanf (div, "%d", &netbits) != 1)
+	    {
+	      msg (D_PF_INFO, "PF: %s/%d: bad '/n' subnet specifier: '%s'", prefix, line_num, div);
+	      return false;
+	    }
+	  if (netbits < 0 || netbits > 32)
+	    {
+	      msg (D_PF_INFO, "PF: %s/%d: bad '/n' subnet specifier: must be between 0 and 32: '%s'", prefix, line_num, div);
+	      return false;
+	    }
+	}
+
+      if (openvpn_inet_aton (line, &network) != OIA_IP)
+	{
+	  msg (D_PF_INFO, "PF: %s/%d: bad network address: '%s'", prefix, line_num, line);
+	  return false;
+	}
+      netmask = netbits_to_netmask (netbits);
+      if ((network.s_addr & htonl (netmask)) != network.s_addr)
+        {
+          network.s_addr &= htonl (netmask);
+          msg (M_WARN, "WARNING: PF: %s/%d: incorrect subnet %s/%d changed to %s/%d", prefix, line_num, line, netbits, inet_ntoa (network), netbits);
+        }
+    }
+  else
+    {
+      /* match special "unknown" tag for addresses unrecognized by mroute */
+      network.s_addr = htonl(0);
+      netmask = IPV4_NETMASK_HOST;
+    }
+
+  {
+    struct pf_subnet *e;
+    ALLOC_OBJ_CLEAR (e, struct pf_subnet);
+    e->rule.exclude = exclude;
+    e->rule.network = ntohl (network.s_addr);
+    e->rule.netmask = netmask;
+    **next = e;
+    *next = &e->next;
+    return true;
+  }
+}
+
+static uint32_t
+cn_hash_function (const void *key, uint32_t iv)
+{
+  return hash_func ((uint8_t *)key, strlen ((char *)key) + 1, iv);
+}
+
+static bool
+cn_compare_function (const void *key1, const void *key2)
+{
+  return !strcmp((const char *)key1, (const char *)key2);
+}
+
+static bool
+genhash (struct pf_cn_set *cns, const char *prefix, const int n_clients)
+{
+  struct pf_cn_elem *e;
+  bool status = true;
+  int n_buckets = n_clients;
+
+  if (n_buckets < 16)
+    n_buckets = 16;
+  cns->hash_table = hash_init (n_buckets, 0, cn_hash_function, cn_compare_function);
+  for (e = cns->list; e != NULL; e = e->next)
+    {
+      if (!hash_add (cns->hash_table, e->rule.cn, &e->rule, false))
+	{
+	  msg (D_PF_INFO, "PF: %s: duplicate common name in [clients] section: '%s'", prefix, e->rule.cn);
+	  status = false;
+	}
+    }
+  
+  return status;
+}
+
+static struct pf_set *
+pf_init (const struct buffer_list *bl, const char *prefix, const bool allow_kill)
+{
+# define MODE_UNDEF   0
+# define MODE_CLIENTS 1
+# define MODE_SUBNETS 2
+  int mode = MODE_UNDEF;
+  int line_num = 0;
+  int n_clients = 0;
+  int n_subnets = 0;
+  int n_errors = 0;
+  struct pf_set *pfs = NULL;
+  char line[PF_MAX_LINE_LEN];
+
+  ALLOC_OBJ_CLEAR (pfs, struct pf_set);
+  if (bl)
+    {
+      struct pf_cn_elem **cl = &pfs->cns.list;
+      struct pf_subnet **sl = &pfs->sns.list;
+      struct buffer_entry *be;
+
+      for (be = bl->head; be != NULL; be = be->next)
+	{
+	  ++line_num;
+	  strncpynt (line, BSTR(&be->buf), sizeof(line));
+	  rm_trailing_chars (line, "\r\n\t ");
+	  if (line[0] == '\0' || line[0] == '#')
+	    ;
+	  else if (line[0] == '+' || line[0] == '-')
+	    {
+	      bool exclude = (line[0] == '-');
+
+	      if (line[1] =='\0')
+		{
+		  msg (D_PF_INFO, "PF: %s/%d: no data after +/-: '%s'", prefix, line_num, line);
+		  ++n_errors;
+		}
+	      else if (mode == MODE_CLIENTS)
+		{
+		  if (add_client (&line[1], prefix, line_num, &cl, exclude))
+		    ++n_clients;
+		  else
+		    ++n_errors;
+		}
+	      else if (mode == MODE_SUBNETS)
+		{
+		  if (add_subnet (&line[1], prefix, line_num, &sl, exclude))
+		    ++n_subnets;
+		  else
+		    ++n_errors;
+		}
+	      else if (mode == MODE_UNDEF)
+		;
+	      else
+		{
+		  ASSERT (0);
+		}
+	    }
+	  else if (line[0] == '[')
+	    {
+	      if (!strcasecmp (line, "[clients accept]"))
+		{
+		  mode = MODE_CLIENTS;
+		  pfs->cns.default_allow = true;
+		}
+	      else if (!strcasecmp (line, "[clients drop]"))
+		{
+		  mode = MODE_CLIENTS;
+		  pfs->cns.default_allow = false;
+		}
+	      else if (!strcasecmp (line, "[subnets accept]"))
+		{
+		  mode = MODE_SUBNETS;
+		  pfs->sns.default_allow = true;
+		}
+	      else if (!strcasecmp (line, "[subnets drop]"))
+		{
+		  mode = MODE_SUBNETS;
+		  pfs->sns.default_allow = false;
+		}
+	      else if (!strcasecmp (line, "[end]"))
+		goto done;
+	      else if (allow_kill && !strcasecmp (line, "[kill]"))
+		goto kill;
+	      else
+		{
+		  mode = MODE_UNDEF;
+		  msg (D_PF_INFO, "PF: %s/%d unknown tag: '%s'", prefix, line_num, line);
+		  ++n_errors;
+		}
+	    }
+	  else
+	    {
+	      msg (D_PF_INFO, "PF: %s/%d line must begin with '+', '-', or '[' : '%s'", prefix, line_num, line);
+	      ++n_errors;
+	    }
+	}
+      ++n_errors;
+      msg (D_PF_INFO, "PF: %s: missing [end]", prefix);
+    }
+  else
+    {
+      msg (D_PF_INFO, "PF: %s: cannot open", prefix);
+      ++n_errors;
+    }
+
+ done:
+  if (bl)
+    {
+      if (!n_errors)
+	{
+	  if (!genhash (&pfs->cns, prefix, n_clients))
+	    ++n_errors;
+	}
+      if (n_errors)
+	msg (D_PF_INFO, "PF: %s rejected due to %d error(s)", prefix, n_errors);
+    }
+  if (n_errors)
+    {
+      pf_destroy (pfs);
+      pfs = NULL;
+    }
+  return pfs;
+  
+ kill:
+  pf_destroy (pfs);
+  ALLOC_OBJ_CLEAR (pfs, struct pf_set);
+  pfs->kill = true;
+  return pfs;
+}
+
+#ifdef PLUGIN_PF
+static struct pf_set *
+pf_init_from_file (const char *fn)
+{
+  struct buffer_list *bl = buffer_list_file (fn, PF_MAX_LINE_LEN);
+  if (bl)
+    {
+      struct pf_set *pfs = pf_init (bl, fn, true);
+      buffer_list_free (bl);
+      return pfs;
+    }
+  else
+    {
+      msg (D_PF_INFO|M_ERRNO, "PF: %s: cannot open", fn);
+      return NULL;
+    }
+}
+#endif
+
+#ifdef ENABLE_DEBUG
+
+static const char *
+drop_accept (const bool accept)
+{
+  return accept ? "ACCEPT" : "DROP"; 
+}
+
+static const char *
+pct_name (const int type)
+{
+  switch (type)
+    {
+    case PCT_SRC:
+      return "SRC";
+    case PCT_DEST:
+      return "DEST";
+    default:
+      return "???";
+    }
+}
+
+static void
+pf_cn_test_print (const char *prefix,
+		  const int type,
+		  const char *prefix2,
+		  const char *cn,
+		  const bool allow,
+		  const struct pf_cn *rule)
+{
+  if (rule)
+    {
+      dmsg (D_PF_DEBUG, "PF: %s/%s/%s %s %s rule=[%s %s]",
+	   prefix, prefix2, pct_name (type),
+	   cn, drop_accept (allow),
+	   rule->cn, drop_accept (!rule->exclude));
+    }
+  else
+    {
+      dmsg (D_PF_DEBUG, "PF: %s/%s/%s %s %s",
+	   prefix, prefix2, pct_name (type),
+	   cn, drop_accept (allow));
+    }
+}
+
+static void
+pf_addr_test_print (const char *prefix,
+		    const char *prefix2,
+		    const struct context *src,
+		    const struct mroute_addr *dest,
+		    const bool allow,
+		    const struct ipv4_subnet *rule)
+{
+  struct gc_arena gc = gc_new ();
+  if (rule)
+    {
+      dmsg (D_PF_DEBUG, "PF: %s/%s %s %s %s rule=[%s/%s %s]",
+	   prefix,
+	   prefix2,
+	   tls_common_name (src->c2.tls_multi, false),
+	   mroute_addr_print_ex (dest, MAPF_SHOW_ARP, &gc),
+	   drop_accept (allow),
+	   print_in_addr_t (rule->network, 0, &gc),
+	   print_in_addr_t (rule->netmask, 0, &gc),
+	   drop_accept (!rule->exclude));
+    }
+  else
+    {
+      dmsg (D_PF_DEBUG, "PF: %s/%s %s %s %s",
+	   prefix,
+	   prefix2,
+	   tls_common_name (src->c2.tls_multi, false),
+	   mroute_addr_print_ex (dest, MAPF_SHOW_ARP, &gc),
+	   drop_accept (allow));
+    }
+  gc_free (&gc);
+}
+
+#endif
+
+static inline struct pf_cn *
+lookup_cn_rule (struct hash *h, const char *cn, const uint32_t cn_hash)
+{
+  struct hash_element *he = hash_lookup_fast (h, hash_bucket (h, cn_hash), cn, cn_hash);
+  if (he)
+    return (struct pf_cn *) he->value;
+  else
+    return NULL;
+}
+
+bool
+pf_cn_test (struct pf_set *pfs, const struct tls_multi *tm, const int type, const char *prefix)
+{
+  if (!pfs->kill)
+    {
+      const char *cn;
+      uint32_t cn_hash;
+      if (tls_common_name_hash (tm, &cn, &cn_hash))
+	{
+	  const struct pf_cn *rule = lookup_cn_rule (pfs->cns.hash_table, cn, cn_hash);
+	  if (rule)
+	    {
+#ifdef ENABLE_DEBUG
+	      if (check_debug_level (D_PF_DEBUG))
+		pf_cn_test_print ("PF_CN_MATCH", type, prefix, cn, !rule->exclude, rule);
+#endif
+	      if (!rule->exclude)
+		return true;
+	      else
+		return false;
+	    }
+	  else
+	    {
+#ifdef ENABLE_DEBUG
+	      if (check_debug_level (D_PF_DEBUG))
+		pf_cn_test_print ("PF_CN_DEFAULT", type, prefix, cn, pfs->cns.default_allow, NULL);
+#endif
+	      if (pfs->cns.default_allow)
+		return true;
+	      else
+		return false;
+	    }
+	}
+    }
+#ifdef ENABLE_DEBUG
+  if (check_debug_level (D_PF_DEBUG))
+    pf_cn_test_print ("PF_CN_FAULT", type, prefix, tls_common_name (tm, false), false, NULL);
+#endif
+  return false;
+}
+
+bool
+pf_addr_test_dowork (const struct context *src, const struct mroute_addr *dest, const char *prefix)
+{
+  struct pf_set *pfs = src->c2.pf.pfs;
+  if (pfs && !pfs->kill)
+    {
+      const in_addr_t addr = in_addr_t_from_mroute_addr (dest);
+      const struct pf_subnet *se = pfs->sns.list;
+      while (se)
+	{
+	  if ((addr & se->rule.netmask) == se->rule.network)
+	    {
+#ifdef ENABLE_DEBUG
+	      if (check_debug_level (D_PF_DEBUG))
+		pf_addr_test_print ("PF_ADDR_MATCH", prefix, src, dest, !se->rule.exclude, &se->rule);
+#endif
+	      return !se->rule.exclude;
+	    }
+	  se = se->next;
+	}
+#ifdef ENABLE_DEBUG
+      if (check_debug_level (D_PF_DEBUG))
+	pf_addr_test_print ("PF_ADDR_DEFAULT", prefix, src, dest, pfs->sns.default_allow, NULL);
+#endif
+      return pfs->sns.default_allow;
+    }
+  else
+    {
+#ifdef ENABLE_DEBUG
+      if (check_debug_level (D_PF_DEBUG))
+	pf_addr_test_print ("PF_ADDR_FAULT", prefix, src, dest, false, NULL);
+#endif
+      return false;
+    }
+}
+
+#ifdef PLUGIN_PF
+void
+pf_check_reload (struct context *c)
+{
+  const int slow_wakeup = 15;
+  const int fast_wakeup = 1;
+  const int wakeup_transition = 60;
+  bool reloaded = false;
+
+  if (c->c2.pf.enabled
+      && c->c2.pf.filename
+      && event_timeout_trigger (&c->c2.pf.reload, &c->c2.timeval, ETT_DEFAULT))
+    {
+      platform_stat_t s;
+      if (!platform_stat (c->c2.pf.filename, &s))
+	{
+	  if (s.st_mtime > c->c2.pf.file_last_mod)
+	    {
+	      struct pf_set *pfs = pf_init_from_file (c->c2.pf.filename);
+	      if (pfs)
+		{
+		  if (c->c2.pf.pfs)
+		    pf_destroy (c->c2.pf.pfs);
+		  c->c2.pf.pfs = pfs;
+		  reloaded = true;
+		  if (pf_kill_test (pfs))
+		    {
+		      c->sig->signal_received = SIGTERM;
+		      c->sig->signal_text = "pf-kill";
+		    }
+		}
+	      c->c2.pf.file_last_mod = s.st_mtime;
+	    }
+	}
+      {
+	int wakeup = slow_wakeup;
+	if (!c->c2.pf.pfs && c->c2.pf.n_check_reload < wakeup_transition)
+	  wakeup = fast_wakeup;
+	event_timeout_init (&c->c2.pf.reload, wakeup, now);
+	reset_coarse_timers (c);
+	c->c2.pf.n_check_reload++;
+      }
+    }
+#ifdef ENABLE_DEBUG
+  if (reloaded && check_debug_level (D_PF_DEBUG))
+    pf_context_print (&c->c2.pf, "pf_check_reload", D_PF_DEBUG);
+#endif
+}
+#endif
+
+#ifdef MANAGEMENT_PF
+bool
+pf_load_from_buffer_list (struct context *c, const struct buffer_list *config)
+{
+  struct pf_set *pfs = pf_init (config, "[SERVER-PF]", false);
+  if (pfs)
+    {
+      if (c->c2.pf.pfs)
+	pf_destroy (c->c2.pf.pfs);
+      c->c2.pf.pfs = pfs;
+      return true;
+    }
+  else
+    return false;
+}
+#endif
+
+void
+pf_init_context (struct context *c)
+{
+  struct gc_arena gc = gc_new ();
+#ifdef PLUGIN_PF
+  if (plugin_defined (c->plugins, OPENVPN_PLUGIN_ENABLE_PF))
+    {
+      const char *pf_file = create_temp_file (c->options.tmp_dir, "pf", &gc);
+      if( pf_file ) {
+        setenv_str (c->c2.es, "pf_file", pf_file);
+
+        if (plugin_call (c->plugins, OPENVPN_PLUGIN_ENABLE_PF, NULL, NULL, c->c2.es) == OPENVPN_PLUGIN_FUNC_SUCCESS)
+          {
+            event_timeout_init (&c->c2.pf.reload, 1, now);
+            c->c2.pf.filename = string_alloc (pf_file, &c->c2.gc);
+            c->c2.pf.enabled = true;
+#ifdef ENABLE_DEBUG
+            if (check_debug_level (D_PF_DEBUG))
+              pf_context_print (&c->c2.pf, "pf_init_context#1", D_PF_DEBUG);
+#endif
+          }
+        else
+          {
+            msg (M_WARN, "WARNING: OPENVPN_PLUGIN_ENABLE_PF disabled");
+          }
+      }
+    }
+#endif
+#ifdef MANAGEMENT_PF
+  if (!c->c2.pf.enabled && management_enable_pf (management))
+    {
+      c->c2.pf.enabled = true;
+#ifdef ENABLE_DEBUG
+      if (check_debug_level (D_PF_DEBUG))
+	pf_context_print (&c->c2.pf, "pf_init_context#2", D_PF_DEBUG);
+#endif
+    }
+#endif
+  gc_free (&gc);
+}
+
+void
+pf_destroy_context (struct pf_context *pfc)
+{
+#ifdef PLUGIN_PF
+  if (pfc->filename)
+    {
+      platform_unlink (pfc->filename);
+      free (pfc->filename);
+    }
+#endif
+  if (pfc->pfs)
+    pf_destroy (pfc->pfs);
+}
+
+#ifdef ENABLE_DEBUG
+
+static void
+pf_subnet_set_print (const struct pf_subnet_set *s, const int lev)
+{
+  struct gc_arena gc = gc_new ();
+  if (s)
+    {
+      struct pf_subnet *e;
+
+      msg (lev, "  ----- struct pf_subnet_set -----");
+      msg (lev, "  default_allow=%s", drop_accept (s->default_allow));
+
+      for (e = s->list; e != NULL; e = e->next)
+	{
+	  msg (lev, "   %s/%s %s",
+	       print_in_addr_t (e->rule.network, 0, &gc),
+	       print_in_addr_t (e->rule.netmask, 0, &gc),
+	       drop_accept (!e->rule.exclude));
+	}
+    }
+  gc_free (&gc);
+}
+
+static void
+pf_cn_set_print (const struct pf_cn_set *s, const int lev)
+{
+  if (s)
+    {
+      struct hash_iterator hi;
+      struct hash_element *he;
+
+      msg (lev, "  ----- struct pf_cn_set -----");
+      msg (lev, "  default_allow=%s", drop_accept (s->default_allow));
+
+      if (s->hash_table)
+	{
+	  hash_iterator_init (s->hash_table, &hi);
+	  while ((he = hash_iterator_next (&hi)))
+	    {
+	      struct pf_cn *e = (struct pf_cn *)he->value;
+	      msg (lev, "   %s %s",
+		   e->cn,
+		   drop_accept (!e->exclude));
+	    }
+
+	  msg (lev, "  ----------");
+
+	  {
+	    struct pf_cn_elem *ce;
+	    for (ce = s->list; ce != NULL; ce = ce->next)
+	      {
+		struct pf_cn *e = lookup_cn_rule (s->hash_table, ce->rule.cn, cn_hash_function (ce->rule.cn, 0));
+		if (e)
+		  {
+		    msg (lev, "   %s %s",
+			 e->cn,
+			 drop_accept (!e->exclude));
+		  }
+		else
+		  {
+		    msg (lev, "   %s LOOKUP FAILED", ce->rule.cn);
+		  }
+	      }
+	  }
+	}
+    }
+}
+
+static void
+pf_set_print (const struct pf_set *pfs, const int lev)
+{
+  if (pfs)
+    {
+      msg (lev, " ----- struct pf_set -----");
+      msg (lev, " kill=%d", pfs->kill);
+      pf_subnet_set_print (&pfs->sns, lev);
+      pf_cn_set_print (&pfs->cns, lev);
+    }
+}
+
+void
+pf_context_print (const struct pf_context *pfc, const char *prefix, const int lev)
+{
+  msg (lev, "----- %s : struct pf_context -----", prefix);
+  if (pfc)
+    {
+      msg (lev, "enabled=%d", pfc->enabled);
+#ifdef PLUGIN_PF
+      msg (lev, "filename='%s'", np(pfc->filename));
+      msg (lev, "file_last_mod=%u", (unsigned int)pfc->file_last_mod);
+      msg (lev, "n_check_reload=%u", pfc->n_check_reload);
+      msg (lev, "reload=[%d,%u,%u]", pfc->reload.defined, pfc->reload.n, (unsigned int)pfc->reload.last);
+#endif
+      pf_set_print (pfc->pfs, lev);
+    }
+  msg (lev, "--------------------");
+}
+
+#endif
+
+#endif