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-rw-r--r--src/nat/nat_mini.c591
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diff --git a/src/nat/nat_mini.c b/src/nat/nat_mini.c
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+++ b/src/nat/nat_mini.c
@@ -0,0 +1,591 @@
+/*
+ This file is part of GNUnet.
+ (C) 2011 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet 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 GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file nat/nat_mini.c
+ * @brief functions for interaction with miniupnp; tested with miniupnpc 1.5
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_nat_lib.h"
+#include "nat.h"
+
+#define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
+
+/**
+ * How long do we give upnpc to create a mapping?
+ */
+#define MAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
+
+/**
+ * How long do we give upnpc to remove a mapping?
+ */
+#define UNMAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
+
+/**
+ * How often do we check for changes in the mapping?
+ */
+#define MAP_REFRESH_FREQ GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
+
+
+
+/**
+ * Opaque handle to cancel "GNUNET_NAT_mini_get_external_ipv4" operation.
+ */
+struct GNUNET_NAT_ExternalHandle
+{
+
+ /**
+ * Function to call with the result.
+ */
+ GNUNET_NAT_IPCallback cb;
+
+ /**
+ * Closure for 'cb'.
+ */
+ void *cb_cls;
+
+ /**
+ * Read task.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier task;
+
+ /**
+ * Handle to 'external-ip' process.
+ */
+ struct GNUNET_OS_Process *eip;
+
+ /**
+ * Handle to stdout pipe of 'external-ip'.
+ */
+ struct GNUNET_DISK_PipeHandle *opipe;
+
+ /**
+ * Read handle of 'opipe'.
+ */
+ const struct GNUNET_DISK_FileHandle *r;
+
+ /**
+ * When should this operation time out?
+ */
+ struct GNUNET_TIME_Absolute timeout;
+
+ /**
+ * Number of bytes in 'buf' that are valid.
+ */
+ size_t off;
+
+ /**
+ * Destination of our read operation (output of 'external-ip').
+ */
+ char buf[17];
+
+};
+
+
+/**
+ * Read the output of 'external-ip' into buf. When complete, parse the
+ * address and call our callback.
+ *
+ * @param cls the 'struct GNUNET_NAT_ExternalHandle'
+ * @param tc scheduler context
+ */
+static void
+read_external_ipv4 (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_ExternalHandle *eh = cls;
+ ssize_t ret;
+ struct in_addr addr;
+ int iret;
+
+ eh->task = GNUNET_SCHEDULER_NO_TASK;
+ if (GNUNET_YES == GNUNET_NETWORK_fdset_handle_isset (tc->read_ready, eh->r))
+ ret =
+ GNUNET_DISK_file_read (eh->r, &eh->buf[eh->off],
+ sizeof (eh->buf) - eh->off);
+ else
+ ret = -1; /* error reading, timeout, etc. */
+ if (ret > 0)
+ {
+ /* try to read more */
+ eh->off += ret;
+ eh->task =
+ GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_absolute_get_remaining
+ (eh->timeout), eh->r,
+ &read_external_ipv4, eh);
+ return;
+ }
+ iret = GNUNET_NO;
+ if ((eh->off > 7) && (eh->buf[eh->off - 1] == '\n'))
+ {
+ eh->buf[eh->off - 1] = '\0';
+ if (1 == inet_pton (AF_INET, eh->buf, &addr))
+ {
+ if (addr.s_addr == 0)
+ iret = GNUNET_NO; /* got 0.0.0.0 */
+ else
+ iret = GNUNET_OK;
+ }
+ }
+ eh->cb (eh->cb_cls, (iret == GNUNET_OK) ? &addr : NULL);
+ GNUNET_NAT_mini_get_external_ipv4_cancel (eh);
+}
+
+
+/**
+ * Try to get the external IPv4 address of this peer.
+ *
+ * @param timeout when to fail
+ * @param cb function to call with result
+ * @param cb_cls closure for 'cb'
+ * @return handle for cancellation (can only be used until 'cb' is called), NULL on error
+ */
+struct GNUNET_NAT_ExternalHandle *
+GNUNET_NAT_mini_get_external_ipv4 (struct GNUNET_TIME_Relative timeout,
+ GNUNET_NAT_IPCallback cb, void *cb_cls)
+{
+ struct GNUNET_NAT_ExternalHandle *eh;
+
+ if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary ("external-ip"))
+ return NULL;
+ eh = GNUNET_malloc (sizeof (struct GNUNET_NAT_ExternalHandle));
+ eh->cb = cb;
+ eh->cb_cls = cb_cls;
+ eh->opipe = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES);
+ if (NULL == eh->opipe)
+ {
+ GNUNET_free (eh);
+ return NULL;
+ }
+ eh->eip =
+ GNUNET_OS_start_process (GNUNET_NO, NULL, eh->opipe, "external-ip", "external-ip",
+ NULL);
+ if (NULL == eh->eip)
+ {
+ GNUNET_DISK_pipe_close (eh->opipe);
+ GNUNET_free (eh);
+ return NULL;
+ }
+ GNUNET_DISK_pipe_close_end (eh->opipe, GNUNET_DISK_PIPE_END_WRITE);
+ eh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+ eh->r = GNUNET_DISK_pipe_handle (eh->opipe, GNUNET_DISK_PIPE_END_READ);
+ eh->task =
+ GNUNET_SCHEDULER_add_read_file (timeout, eh->r, &read_external_ipv4, eh);
+ return eh;
+}
+
+
+/**
+ * Cancel operation.
+ *
+ * @param eh operation to cancel
+ */
+void
+GNUNET_NAT_mini_get_external_ipv4_cancel (struct GNUNET_NAT_ExternalHandle *eh)
+{
+ (void) GNUNET_OS_process_kill (eh->eip, SIGKILL);
+ GNUNET_OS_process_close (eh->eip);
+ GNUNET_DISK_pipe_close (eh->opipe);
+ if (GNUNET_SCHEDULER_NO_TASK != eh->task)
+ GNUNET_SCHEDULER_cancel (eh->task);
+ GNUNET_free (eh);
+}
+
+
+/**
+ * Handle to a mapping created with upnpc.
+ */
+struct GNUNET_NAT_MiniHandle
+{
+
+ /**
+ * Function to call on mapping changes.
+ */
+ GNUNET_NAT_AddressCallback ac;
+
+ /**
+ * Closure for 'ac'.
+ */
+ void *ac_cls;
+
+ /**
+ * Command used to install the map.
+ */
+ struct GNUNET_OS_CommandHandle *map_cmd;
+
+ /**
+ * Command used to refresh our map information.
+ */
+ struct GNUNET_OS_CommandHandle *refresh_cmd;
+
+ /**
+ * Command used to remove the mapping.
+ */
+ struct GNUNET_OS_CommandHandle *unmap_cmd;
+
+ /**
+ * Our current external mapping (if we have one).
+ */
+ struct sockaddr_in current_addr;
+
+ /**
+ * We check the mapping periodically to see if it
+ * still works. This task triggers the check.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier refresh_task;
+
+ /**
+ * Are we mapping TCP or UDP?
+ */
+ int is_tcp;
+
+ /**
+ * Did we succeed with creating a mapping?
+ */
+ int did_map;
+
+ /**
+ * Did we find our mapping during refresh scan?
+ */
+ int found;
+
+ /**
+ * Which port are we mapping?
+ */
+ uint16_t port;
+
+};
+
+
+/**
+ * Run upnpc -l to find out if our mapping changed.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param tc scheduler context
+ */
+static void
+do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Process the output from the 'upnpc -r' command.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param line line of output, NULL at the end
+ */
+static void
+process_map_output (void *cls, const char *line);
+
+
+/**
+ * Process the output from 'upnpc -l' to see if our
+ * external mapping changed. If so, do the notifications.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param line line of output, NULL at the end
+ */
+static void
+process_refresh_output (void *cls, const char *line)
+{
+ struct GNUNET_NAT_MiniHandle *mini = cls;
+ char pstr[9];
+ const char *s;
+ unsigned int nport;
+ struct in_addr exip;
+
+ if (NULL == line)
+ {
+ GNUNET_OS_command_stop (mini->refresh_cmd);
+ mini->refresh_cmd = NULL;
+ if (mini->found == GNUNET_NO)
+ {
+ /* mapping disappeared, try to re-create */
+ if (mini->did_map)
+ {
+ mini->ac (mini->ac_cls, GNUNET_NO,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+ mini->did_map = GNUNET_NO;
+ }
+ GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) mini->port);
+ mini->map_cmd =
+ GNUNET_OS_command_run (&process_map_output, mini, MAP_TIMEOUT,
+ "upnpc", "upnpc", "-r", pstr,
+ mini->is_tcp ? "tcp" : "udp", NULL);
+ if (NULL != mini->map_cmd)
+ return;
+ }
+ mini->refresh_task =
+ GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
+ return;
+ }
+ if (!mini->did_map)
+ return; /* never mapped, won't find our mapping anyway */
+
+ /* we're looking for output of the form:
+ * "ExternalIPAddress = 12.134.41.124" */
+
+ s = strstr (line, "ExternalIPAddress = ");
+ if (NULL != s)
+ {
+ s += strlen ("ExternalIPAddress = ");
+ if (1 != inet_pton (AF_INET, s, &exip))
+ return; /* skip */
+ if (exip.s_addr == mini->current_addr.sin_addr.s_addr)
+ return; /* no change */
+ /* update mapping */
+ mini->ac (mini->ac_cls, GNUNET_NO,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+ mini->current_addr.sin_addr = exip;
+ mini->ac (mini->ac_cls, GNUNET_YES,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+ return;
+ }
+ /*
+ * we're looking for output of the form:
+ *
+ * "0 TCP 3000->192.168.2.150:3000 'libminiupnpc' ''"
+ * "1 UDP 3001->192.168.2.150:3001 'libminiupnpc' ''"
+ *
+ * the pattern we look for is:
+ *
+ * "%s TCP PORT->STRING:OURPORT *" or
+ * "%s UDP PORT->STRING:OURPORT *"
+ */
+ GNUNET_snprintf (pstr, sizeof (pstr), ":%u ", mini->port);
+ if (NULL == (s = strstr (line, "->")))
+ return; /* skip */
+ if (NULL == strstr (s, pstr))
+ return; /* skip */
+ if (1 !=
+ sscanf (line,
+ (mini->is_tcp) ? "%*u TCP %u->%*s:%*u %*s" :
+ "%*u UDP %u->%*s:%*u %*s", &nport))
+ return; /* skip */
+ mini->found = GNUNET_YES;
+ if (nport == ntohs (mini->current_addr.sin_port))
+ return; /* no change */
+
+ /* external port changed, update mapping */
+ mini->ac (mini->ac_cls, GNUNET_NO,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+ mini->current_addr.sin_port = htons ((uint16_t) nport);
+ mini->ac (mini->ac_cls, GNUNET_YES,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+}
+
+
+/**
+ * Run upnpc -l to find out if our mapping changed.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param tc scheduler context
+ */
+static void
+do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_MiniHandle *mini = cls;
+
+ mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
+ mini->found = GNUNET_NO;
+ mini->refresh_cmd =
+ GNUNET_OS_command_run (&process_refresh_output, mini, MAP_TIMEOUT,
+ "upnpc", "upnpc", "-l", NULL);
+}
+
+
+/**
+ * Process the output from the 'upnpc -r' command.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param line line of output, NULL at the end
+ */
+static void
+process_map_output (void *cls, const char *line)
+{
+ struct GNUNET_NAT_MiniHandle *mini = cls;
+ const char *ipaddr;
+ char *ipa;
+ const char *pstr;
+ unsigned int port;
+
+ if (NULL == line)
+ {
+ GNUNET_OS_command_stop (mini->map_cmd);
+ mini->map_cmd = NULL;
+ mini->refresh_task =
+ GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
+ return;
+ }
+ /*
+ * The upnpc output we're after looks like this:
+ *
+ * "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
+ */
+ if ((NULL == (ipaddr = strstr (line, " "))) ||
+ (NULL == (pstr = strstr (ipaddr, ":"))) ||
+ (1 != sscanf (pstr + 1, "%u", &port)))
+ {
+ return; /* skip line */
+ }
+ ipa = GNUNET_strdup (ipaddr + 1);
+ strstr (ipa, ":")[0] = '\0';
+ if (1 != inet_pton (AF_INET, ipa, &mini->current_addr.sin_addr))
+ {
+ GNUNET_free (ipa);
+ return; /* skip line */
+ }
+ GNUNET_free (ipa);
+
+ mini->current_addr.sin_port = htons (port);
+ mini->current_addr.sin_family = AF_INET;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ mini->current_addr.sin_len = sizeof (struct sockaddr_in);
+#endif
+ mini->did_map = GNUNET_YES;
+ mini->ac (mini->ac_cls, GNUNET_YES,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+}
+
+
+/**
+ * Start mapping the given port using (mini)upnpc. This function
+ * should typically not be used directly (it is used within the
+ * general-purpose 'GNUNET_NAT_register' code). However, it can be
+ * used if specifically UPnP-based NAT traversal is to be used or
+ * tested.
+ *
+ * @param port port to map
+ * @param is_tcp GNUNET_YES to map TCP, GNUNET_NO for UDP
+ * @param ac function to call with mapping result
+ * @param ac_cls closure for 'ac'
+ * @return NULL on error (no 'upnpc' installed)
+ */
+struct GNUNET_NAT_MiniHandle *
+GNUNET_NAT_mini_map_start (uint16_t port, int is_tcp,
+ GNUNET_NAT_AddressCallback ac, void *ac_cls)
+{
+ struct GNUNET_NAT_MiniHandle *ret;
+ char pstr[6];
+
+ if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary ("upnpc"))
+ return NULL;
+ ret = GNUNET_malloc (sizeof (struct GNUNET_NAT_MiniHandle));
+ ret->ac = ac;
+ ret->ac_cls = ac_cls;
+ ret->is_tcp = is_tcp;
+ ret->port = port;
+ GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) port);
+ ret->map_cmd =
+ GNUNET_OS_command_run (&process_map_output, ret, MAP_TIMEOUT, "upnpc",
+ "upnpc", "-r", pstr, is_tcp ? "tcp" : "udp", NULL);
+ if (NULL != ret->map_cmd)
+ return ret;
+ ret->refresh_task =
+ GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, ret);
+
+ return ret;
+}
+
+
+/**
+ * Process output from our 'unmap' command.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param line line of output, NULL at the end
+ */
+static void
+process_unmap_output (void *cls, const char *line)
+{
+ struct GNUNET_NAT_MiniHandle *mini = cls;
+
+ if (NULL == line)
+ {
+#if DEBUG_NAT
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "UPnP unmap done\n");
+#endif
+ GNUNET_OS_command_stop (mini->unmap_cmd);
+ mini->unmap_cmd = NULL;
+ GNUNET_free (mini);
+ return;
+ }
+ /* we don't really care about the output... */
+}
+
+
+/**
+ * Remove a mapping created with (mini)upnpc. Calling
+ * this function will give 'upnpc' 1s to remove tha mapping,
+ * so while this function is non-blocking, a task will be
+ * left with the scheduler for up to 1s past this call.
+ *
+ * @param mini the handle
+ */
+void
+GNUNET_NAT_mini_map_stop (struct GNUNET_NAT_MiniHandle *mini)
+{
+ char pstr[6];
+
+ if (GNUNET_SCHEDULER_NO_TASK != mini->refresh_task)
+ {
+ GNUNET_SCHEDULER_cancel (mini->refresh_task);
+ mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (mini->refresh_cmd != NULL)
+ {
+ GNUNET_OS_command_stop (mini->refresh_cmd);
+ mini->refresh_cmd = NULL;
+ }
+ if (!mini->did_map)
+ {
+ if (mini->map_cmd != NULL)
+ {
+ GNUNET_OS_command_stop (mini->map_cmd);
+ mini->map_cmd = NULL;
+ }
+ GNUNET_free (mini);
+ return;
+ }
+ mini->ac (mini->ac_cls, GNUNET_NO,
+ (const struct sockaddr *) &mini->current_addr,
+ sizeof (mini->current_addr));
+ /* Note: oddly enough, deletion uses the external port whereas
+ * addition uses the internal port; this rarely matters since they
+ * often are the same, but it might... */
+ GNUNET_snprintf (pstr, sizeof (pstr), "%u",
+ (unsigned int) ntohs (mini->current_addr.sin_port));
+#if DEBUG_NAT
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Unmapping port %u with UPnP\n",
+ ntohs (mini->current_addr.sin_port));
+#endif
+ mini->unmap_cmd =
+ GNUNET_OS_command_run (&process_unmap_output, mini, UNMAP_TIMEOUT,
+ "upnpc", "upnpc", "-d", pstr,
+ mini->is_tcp ? "tcp" : "udp", NULL);
+}
+
+
+/* end of nat_mini.c */
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-21 14:00:59 +0000