[GNUnet-SVN] r20875 - gnunet/src/transport

[gnunet]

Author: grothoff
Date: 2012-04-03 14:58:37 +0200 (Tue, 03 Apr 2012)
New Revision: 20875

Modified:
   gnunet/src/transport/gnunet-helper-transport-wlan-dummy.c
   gnunet/src/transport/gnunet-helper-transport-wlan.c
   gnunet/src/transport/plugin_transport_wlan.c
Log:
-fix assertion, documentation, getting dummy to be closer to work on W32

Modified: gnunet/src/transport/gnunet-helper-transport-wlan-dummy.c
===================================================================
--- gnunet/src/transport/gnunet-helper-transport-wlan-dummy.c   2012-04-03 
12:43:46 UTC (rev 20874)
+++ gnunet/src/transport/gnunet-helper-transport-wlan-dummy.c   2012-04-03 
12:58:37 UTC (rev 20875)
@@ -1,6 +1,6 @@
 /*
  This file is part of GNUnet.
- (C) 2010 Christian Grothoff (and other contributing authors)
+ (C) 2010, 2012 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
@@ -27,22 +27,60 @@
 #include "gnunet_util_lib.h"
 #include "plugin_transport_wlan.h"
 
-#define FIFO_FILE1       "/tmp/test-transport/api-wlan-p1/WLAN_FIFO_in"
-#define FIFO_FILE2       "/tmp/test-transport/api-wlan-p1/WLAN_FIFO_out"
+/**
+ * Name of the fifo to use for IPC with the other dummy process.
+ */
+#define FIFO_FILE1 "/tmp/test-transport/api-wlan-p1/WLAN_FIFO_in"
 
+/**
+ * Name of the fifo to use for IPC with the other dummy process.
+ */
+#define FIFO_FILE2 "/tmp/test-transport/api-wlan-p1/WLAN_FIFO_out"
+
+/**
+ * Maximum size of a message allowed in either direction
+ * (used for our receive and sent buffers).
+ */
 #define MAXLINE 4096
 
-struct sendbuf
+
+/**
+ * IO buffer used for buffering data in transit.
+ */
+struct SendBuffer
 {
-  unsigned int pos;
-  unsigned int size;
+
+  /**
+   * How many bytes that were stored in 'buf' did we already write to the
+   * destination?  Always smaller than 'size'.
+   */
+  size_t pos;
+
+  /**
+   * How many bytes of data are stored in 'buf' for transmission right now?
+   * Data always starts at offset 0 and extends to 'size'.
+   */
+  size_t size;
+
+  /**
+   * Buffered data; twice the maximum allowed message size as we add some
+   * headers.
+   */
   char buf[MAXLINE * 2];
 };
 
-static int first;
 
+/**
+ * Flag set to 1 if we are to terminate, otherwise 0.
+ */
 static int closeprog;
 
+
+/**
+ * We're being killed, clean up.
+ *
+ * @param sig killing signal
+ */
 static void
 sigfunc (int sig)
 {
@@ -53,7 +91,8 @@
 
 
 /**
- * function to create GNUNET_MESSAGE_TYPE_WLAN_HELPER_CONTROL message for 
plugin
+ * Create control message for plugin
+ *
  * @param buffer pointer to buffer for the message
  * @param mac pointer to the mac address
  * @return number of bytes written
@@ -67,16 +106,23 @@
   memcpy (&macmsg.mac, (char *) mac, sizeof (struct 
GNUNET_TRANSPORT_WLAN_MacAddress));
   macmsg.hdr.size = htons (sizeof (struct 
GNUNET_TRANSPORT_WLAN_HelperControlMessage));
   macmsg.hdr.type = htons (GNUNET_MESSAGE_TYPE_WLAN_HELPER_CONTROL);
-
   memcpy (buffer, &macmsg, sizeof (struct 
GNUNET_TRANSPORT_WLAN_HelperControlMessage));
   return sizeof (struct GNUNET_TRANSPORT_WLAN_HelperControlMessage);
 }
 
 
+/**
+ * We got a message from the FIFO, check it, convert the message
+ * type to the output forward and copy it to the buffer for stdout.
+ *
+ * @param cls the 'struct SendBuffer' to copy the converted message to
+ * @param client unused
+ * @param hdr inbound message from the FIFO
+ */
 static void
 stdin_send (void *cls, void *client, const struct GNUNET_MessageHeader *hdr)
 {
-  struct sendbuf *write_pout = cls;
+  struct SendBuffer *write_pout = cls;
   const struct GNUNET_TRANSPORT_WLAN_RadiotapSendMessage *in;
   size_t payload_size;
   struct GNUNET_TRANSPORT_WLAN_RadiotapReceiveMessage newheader;
@@ -87,15 +133,13 @@
   if ( (GNUNET_MESSAGE_TYPE_WLAN_DATA_TO_HELPER != ntohs (hdr->type)) ||
        (sizeof (struct GNUNET_TRANSPORT_WLAN_RadiotapSendMessage) > sendsize) )
   {
-    fprintf (stderr, "Received malformed message\n",
-            (unsigned int) sendsize,
-            (unsigned int) ntohs (hdr->type));
+    fprintf (stderr, "Received malformed message\n");
     exit (1);
   }
   payload_size = sendsize - sizeof (struct 
GNUNET_TRANSPORT_WLAN_RadiotapSendMessage);
   if ((payload_size + sizeof (struct 
GNUNET_TRANSPORT_WLAN_RadiotapReceiveMessage) + write_pout->size) > MAXLINE * 2)
   {
-    fprintf (stderr, "Packet too big for buffer\n");
+    FPRINTF (stderr, "%s",  "Packet too big for buffer\n");
     exit (1);
   }
   memset (&newheader, 0, sizeof (newheader));
@@ -113,24 +157,37 @@
 }
 
 
+/**
+ * We read a full message from stdin.  Copy it to our send buffer.
+ *
+ * @param cls the 'struct SendBuffer' to copy to
+ * @param client unused
+ * @param hdr the message we received to copy to the buffer
+ */
 static void
 file_in_send (void *cls, void *client, const struct GNUNET_MessageHeader *hdr)
 {
-  struct sendbuf *write_std = cls;
+  struct SendBuffer *write_std = cls;
   uint16_t sendsize;
 
   sendsize = ntohs (hdr->size);
   if ((sendsize + write_std->size) > MAXLINE * 2)
   {
-    fprintf (stderr, "Function file_in_send: Packet too big for buffer\n");
+    FPRINTF (stderr, "%s", "Packet too big for buffer\n");
     exit (1);
   }
-
   memcpy (write_std->buf + write_std->size, hdr, sendsize);
   write_std->size += sendsize;
 }
 
 
+/**
+ * Main function of a program that pretends to be a WLAN card.
+ *
+ * @param argc should be 2
+ * @param argv either '1' or '2', depending on which of the two cards this 
dummy is to emulate
+ * @return 1 on error, 0 if terminated normally via signal
+ */
 int
 main (int argc, char *argv[])
 {
@@ -141,105 +198,98 @@
   int fdpin;
   int fdpout;
   char readbuf[MAXLINE];
-  int readsize = 0;
-  struct sendbuf write_std;
-  struct sendbuf write_pout;
-  int ret = 0;
-  int maxfd = 0;
+  int readsize;
+  struct SendBuffer write_std;
+  struct SendBuffer write_pout;
+  int ret;
+  int maxfd;
   fd_set rfds;
   fd_set wfds;
   struct timeval tv;
   int retval;
-  struct GNUNET_SERVER_MessageStreamTokenizer *stdin_mst;
-  struct GNUNET_SERVER_MessageStreamTokenizer *file_in_mst;
+  struct GNUNET_SERVER_MessageStreamTokenizer *stdin_mst = NULL;
+  struct GNUNET_SERVER_MessageStreamTokenizer *file_in_mst = NULL;
   struct GNUNET_TRANSPORT_WLAN_MacAddress macaddr;
+  int first;
 
-  if (2 != argc)
+  if ( (2 != argc) ||
+       ((0 != strcmp (argv[1], "1")) && (0 != strcmp (argv[1], "2"))) )
   {
-    fprintf (stderr,
-             "This program must be started with the operating mode (1 or 2) as 
the only argument.\n");
+    FPRINTF (stderr,
+             "%s",
+            "This program must be started with the operating mode (1 or 2) as 
the only argument.\n");
     return 1;
   }
-  if ((0 != strstr (argv[1], "1")) && (0 != strstr (argv[1], "2")))
-    return 1;
 
-  //make the fifos if needed
+  /* make the fifos if needed */
   if (0 != stat (FIFO_FILE1, &st))
   {
     if (0 == stat (FIFO_FILE2, &st))
     {
-      fprintf (stderr, "FIFO_FILE2 exists, but FIFO_FILE1 not\n");
+      FPRINTF (stderr, "%s", "FIFO_FILE2 exists, but FIFO_FILE1 not\n");
       exit (1);
     }
     umask (0);
     erg = mkfifo (FIFO_FILE1, 0666);
     if (0 != erg)
     {
-      fprintf (stderr, "Error in mkfifo(%s): %s\n", FIFO_FILE1,
+      FPRINTF (stderr, "Error in mkfifo(%s): %s\n", FIFO_FILE1,
                strerror (errno));
-      //exit(1);
     }
     erg = mkfifo (FIFO_FILE2, 0666);
     if (0 != erg)
     {
-      fprintf (stderr, "Error in mkfifo(%s): %s\n", FIFO_FILE2,
+      FPRINTF (stderr, "Error in mkfifo(%s): %s\n", FIFO_FILE2,
                strerror (errno));
-      //exit(1);
     }
-
   }
   else
   {
     if (0 != stat (FIFO_FILE2, &st))
     {
-      fprintf (stderr, "FIFO_FILE1 exists, but FIFO_FILE2 not\n");
+      FPRINTF (stderr, "%s", "FIFO_FILE1 exists, but FIFO_FILE2 not\n");
       exit (1);
     }
   }
 
-  if (strstr (argv[1], "1"))
+  if (0 != strcmp (argv[1], "1"))
   {
-    //fprintf(stderr, "First\n");
     first = 1;
     fpin = fopen (FIFO_FILE1, "r");
     if (NULL == fpin)
     {
-      fprintf (stderr, "fopen of read FIFO_FILE1\n");
+      FPRINTF (stderr, "fopen of read FIFO_FILE1 failed: %s\n", STRERROR 
(errno));
       goto end;
     }
     fpout = fopen (FIFO_FILE2, "w");
     if (NULL == fpout)
     {
-      fprintf (stderr, "fopen of write FIFO_FILE2\n");
+      FPRINTF (stderr, "fopen of write FIFO_FILE2 failed: %s\n", STRERROR 
(errno));
       goto end;
     }
-
   }
   else
   {
     first = 0;
-    //fprintf(stderr, "Second\n");
     fpout = fopen (FIFO_FILE1, "w");
     if (NULL == fpout)
     {
-      fprintf (stderr, "fopen of write FIFO_FILE1\n");
+      FPRINTF (stderr, "fopen of write FIFO_FILE1 failed: %s\n", STRERROR 
(errno));
       goto end;
     }
     fpin = fopen (FIFO_FILE2, "r");
     if (NULL == fpin)
     {
-      fprintf (stderr, "fopen of read FIFO_FILE2\n");
+      FPRINTF (stderr, "fopen of read FIFO_FILE2 failed: %s\n", STRERROR 
(errno));
       goto end;
     }
-
   }
 
   fdpin = fileno (fpin);
   GNUNET_assert (fpin >= 0);
-
   if (fdpin >= FD_SETSIZE)
   {
-    fprintf (stderr, "File fdpin number too large (%d > %u)\n", fdpin,
+    FPRINTF (stderr, "File fdpin number too large (%d > %u)\n", fdpin,
              (unsigned int) FD_SETSIZE);
     goto end;
   }
@@ -249,10 +299,9 @@
 
   if (fdpout >= FD_SETSIZE)
   {
-    fprintf (stderr, "File fdpout number too large (%d > %u)\n", fdpout,
+    FPRINTF (stderr, "File fdpout number too large (%d > %u)\n", fdpout,
              (unsigned int) FD_SETSIZE);
     goto end;
-
   }
 
   signal (SIGINT, &sigfunc);
@@ -265,7 +314,7 @@
   stdin_mst = GNUNET_SERVER_mst_create (&stdin_send, &write_pout);
   file_in_mst = GNUNET_SERVER_mst_create (&file_in_send, &write_std);
 
-  //Send random mac address
+  /* Send 'random' mac address */
   macaddr.mac[0] = 0x13;
   macaddr.mac[1] = 0x22;
   macaddr.mac[2] = 0x33;
@@ -277,12 +326,12 @@
   while (0 == closeprog)
   {
     maxfd = -1;
-    //set timeout
     tv.tv_sec = 5;
     tv.tv_usec = 0;
 
     FD_ZERO (&rfds);
-    // if output queue is empty
+    FD_ZERO (&wfds);
+    /* if output queue is empty, read */
     if (0 == write_pout.size)
     {
       FD_SET (STDIN_FILENO, &rfds);
@@ -293,8 +342,8 @@
       FD_SET (fdpin, &rfds);
       maxfd = MAX (fdpin, maxfd);
     }
-    FD_ZERO (&wfds);
-    // if there is something to write
+
+    /* if there is something to write, try to write */
     if (0 < write_std.size)
     {
       FD_SET (STDOUT_FILENO, &wfds);
@@ -311,7 +360,7 @@
       continue;
     if (0 > retval)
     {
-      fprintf (stderr, "select failed: %s\n", strerror (errno));
+      FPRINTF (stderr, "select failed: %s\n", STRERROR (errno));
       closeprog = 1;
       break;
     }
@@ -324,14 +373,14 @@
       if (0 > ret)
       {
         closeprog = 1;
-        fprintf (stderr, "Write ERROR to STDOUT_FILENO: %s\n",
-                 strerror (errno));
+        FPRINTF (stderr, "Write ERROR to STDOUT_FILENO: %s\n",
+                 STRERROR (errno));
         break;
       }
       else
       {
         write_std.pos += ret;
-        // check if finished
+        /* check if finished writing */
         if (write_std.pos == write_std.size)
         {
           write_std.pos = 0;
@@ -349,12 +398,12 @@
       if (0 > ret)
       {
         closeprog = 1;
-        fprintf (stderr, "Write ERROR to fdpout: %s\n", strerror (errno));
+        FPRINTF (stderr, "Write ERROR to fdpout failed: %s\n", STRERROR 
(errno));
       }
       else
       {
         write_pout.pos += ret;
-        // check if finished
+        /* check if finished writing */
         if (write_pout.pos == write_pout.size)
         {
           write_pout.pos = 0;
@@ -370,8 +419,8 @@
       if (0 > readsize)
       {
         closeprog = 1;
-        fprintf (stderr, "Error reading from STDIN_FILENO: %s\n",
-                 strerror (errno));
+        FPRINTF (stderr, "Error reading from STDIN_FILENO: %s\n",
+                 STRERROR (errno));
       }
       else if (0 < readsize)
       {
@@ -381,7 +430,7 @@
       }
       else
       {
-        //eof
+        /* eof */
         closeprog = 1;
       }
     }
@@ -392,7 +441,7 @@
       if (0 > readsize)
       {
         closeprog = 1;
-        fprintf (stderr, "Error reading from fdpin: %s\n", strerror (errno));
+        FPRINTF (stderr, "Error reading from fdpin: %s\n", STRERROR (errno));
         break;
       }
       else if (0 < readsize)
@@ -402,20 +451,22 @@
       }
       else
       {
-        //eof
+        /* eof */
         closeprog = 1;
       }
     }
   }
 
-  //clean up
-  GNUNET_SERVER_mst_destroy (stdin_mst);
-  GNUNET_SERVER_mst_destroy (file_in_mst);
+end:
+  /* clean up */
+  if (NULL != stdin_mst)
+    GNUNET_SERVER_mst_destroy (stdin_mst);
+  if (NULL != file_in_mst)
+    GNUNET_SERVER_mst_destroy (file_in_mst);
 
-end:
-  if (fpout != NULL)
+  if (NULL != fpout)
     fclose (fpout);
-  if (fpin != NULL)
+  if (NULL != fpin)
     fclose (fpin);
   if (1 == first)
   {

Modified: gnunet/src/transport/gnunet-helper-transport-wlan.c
===================================================================
--- gnunet/src/transport/gnunet-helper-transport-wlan.c 2012-04-03 12:43:46 UTC 
(rev 20874)
+++ gnunet/src/transport/gnunet-helper-transport-wlan.c 2012-04-03 12:58:37 UTC 
(rev 20875)
@@ -30,18 +30,39 @@
  * interface.  It will force traffic to be in 'ad-hoc' mode, use the
  * proper MAC address of the WLAN interface and use a GNUnet-specific
  * SSID (and a GNUnet-specific SNAP header).  It only takes a single
- * argument, which is the name of the interface to use.  Since it uses
- * RAW sockets, it must be installed SUID or run as 'root'.  In order
- * to keep the security risk of the resulting SUID binary minimal, the
- * program ONLY opens the RAW socket with root privileges, then drops
- * them and only then starts to process command line arguments.  The
- * code also does not link against any shared libraries (except libc)
- * and is strictly minimal (except for checking for errors).  The
- * following list of people have reviewed this code and considered it
- * safe since the last modification (if you reviewed it, please have
- * your name added to the list):
+ * argument, which is the name of the WLAN interface to use.  The
+ * program detects if the interface is not a WLAN interface and exits
+ * with an error in that case.
  *
- * - Christian Grothoff (Mar 16th 2012)
+ * Once initialized, the program will first send a 'struct
+ * GNUNET_TRANSPORT_WLAN_HelperControlMessage' to 'stdout'.  That
+ * message contains the MAC address of the WLAN interface.  It will
+ * then read messages from the WLAN interface and send them together
+ * with performance information as 'struct
+ * GNUNET_TRANSPORT_WLAN_RadiotapReceiveMessage' messages to 'stdout'.
+ * Furthermore, it will read a stream of messages from 'stdin' that
+ * have the format from 'struct
+ * GNUNET_TRANSPORT_WLAN_RadiotapSendMessage'.  Those messages will
+ * then be sent via the WLAN interface; however, the sender MAC
+ * address will be forced to be the correct address from our WLAN
+ * card.  If 'stdin' closes, receiving from the WLAN interface will
+ * continue.  If 'stdout' causes a SIGPIPE, the process dies from the
+ * signal.  Errors cause an error message to be reported to 'stderr',
+ * in most cases the process also exits (with status code '1').  The
+ * program never terminates normally; it is safe to kill the
+ * process with SIGTERM or SIGKILL at any time.
+ *
+ * Since it uses RAW sockets, the binary must be installed SUID or run
+ * as 'root'.  In order to keep the security risk of the resulting
+ * SUID binary minimal, the program ONLY opens the RAW socket with
+ * root privileges, then drops them and only then starts to process
+ * command line arguments.  The code also does not link against any
+ * shared libraries (except libc) and is strictly minimal (except for
+ * checking for errors).  The following list of people have reviewed
+ * this code and considered it safe since the last modification (if
+ * you reviewed it, please have your name added to the list):
+ *
+ * - Christian Grothoff (Apr 3rd 2012)
  */
 
 /*-

Modified: gnunet/src/transport/plugin_transport_wlan.c
===================================================================
--- gnunet/src/transport/plugin_transport_wlan.c        2012-04-03 12:43:46 UTC 
(rev 20874)
+++ gnunet/src/transport/plugin_transport_wlan.c        2012-04-03 12:58:37 UTC 
(rev 20875)
@@ -1003,12 +1003,13 @@
   }
 }
 
+
 /**
  * Function to set the timer for the next timeout of the fragment queue
  * @param plugin the handle to the plugin struct
  */
 static void
-set_next_send (struct Plugin *const plugin)
+set_next_send (struct Plugin *plugin)
 {
   struct GNUNET_TIME_Relative next_send;
 
@@ -1185,7 +1186,6 @@
     }
     fmq = fmq_next;
   }
-
   session->mac->fragment_messages_out_count--;
   session->fragment_messages_out_count--;
   plugin->pending_Fragment_Messages--;
@@ -1766,10 +1766,8 @@
 
   GNUNET_assert (fm != NULL);
   fm->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
-  {
-    return;
-  }
+  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))  
+    return;  
   free_fragment_message (fm->session->mac->plugin, fm);
 }
 
@@ -1908,7 +1906,6 @@
   struct FragmentMessage_queue *fmq;
   ssize_t bytes;
 
-
   GNUNET_assert (plugin != NULL);
   plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
@@ -1926,8 +1923,7 @@
   }
   if (NULL == plugin->sending_messages_head)
   {
-    /* do_transmit did nothing, should not happen */  
-    GNUNET_break (0);
+    /* nothing to do right now, check when to go again */  
     set_next_send (plugin);
     return;
   }
@@ -2241,10 +2237,8 @@
   while (fm != NULL)
   {
     fmnext = fm->next;
-    if (fm->session == queue->content)
-    {
-      free_fragment_message (plugin, fm);
-    }
+    if (fm->session == queue->content)    
+      free_fragment_message (plugin, fm);    
     fm = fmnext;
   }