src/vnet/unix/pcap.c - fdio/vpp - Gitiles

 /*
  * Copyright (c) 2015 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 /*
  * pcap.c: libpcap packet capture format
  *
  * Copyright (c) 2008 Eliot Dresselhaus
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sublicense, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * The above copyright notice and this permission notice shall be
  * included in all copies or substantial portions of the Software.
  *
  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */

 #include <vnet/unix/pcap.h>
 #include <sys/fcntl.h>

 /**
  * @file
  * @brief PCAP function.
  *
  * Usage:
  *
  * <code><pre>
  * \#include <vnet/unix/pcap.h>
  *
  * static pcap_main_t pcap = {
  *  .file_name = "/tmp/ip4",
  *  .n_packets_to_capture = 2,
  *  .packet_type = PCAP_PACKET_TYPE_ip,
  * };
  * </pre></code>
  *
  * To add a buffer:
  *
  *  <code><pre>pcap_add_buffer (&pcap, vm, pi0, 128);</pre></code>
  *
  * File will be written after @c n_packets_to_capture or call to pcap_write (&amp;pcap).
  *
 */

 /**
  * @brief Close PCAP file
  *
  * @return rc - clib_error_t
  *
  */
 clib_error_t *
 pcap_close (pcap_main_t * pm)
 {
   close (pm->file_descriptor);
   pm->flags &= ~PCAP_MAIN_INIT_DONE;
   pm->file_descriptor = -1;
   return 0;
 }

 /**
  * @brief Write PCAP file
  *
  * @return rc - clib_error_t
  *
  */
 clib_error_t *
 pcap_write (pcap_main_t * pm)
 {
   clib_error_t *error = 0;

   if (!(pm->flags & PCAP_MAIN_INIT_DONE))
     {
       pcap_file_header_t fh;
       int n;

       if (!pm->file_name)
 	pm->file_name = "/tmp/vnet.pcap";

       pm->file_descriptor =
 	open (pm->file_name, O_CREAT | O_TRUNC | O_WRONLY, 0664);
       if (pm->file_descriptor < 0)
 	{
 	  error =
 	    clib_error_return_unix (0, "failed to open `%s'", pm->file_name);
 	  goto done;
 	}

       pm->flags |= PCAP_MAIN_INIT_DONE;
       pm->n_packets_captured = 0;
       pm->n_pcap_data_written = 0;

       /* Write file header. */
       memset (&fh, 0, sizeof (fh));
       fh.magic = 0xa1b2c3d4;
       fh.major_version = 2;
       fh.minor_version = 4;
       fh.time_zone = 0;
       fh.max_packet_size_in_bytes = 1 << 16;
       fh.packet_type = pm->packet_type;
       n = write (pm->file_descriptor, &fh, sizeof (fh));
       if (n != sizeof (fh))
 	{
 	  if (n < 0)
 	    error =
 	      clib_error_return_unix (0, "write file header `%s'",
 				      pm->file_name);
 	  else
 	    error =
 	      clib_error_return (0, "short write of file header `%s'",
 				 pm->file_name);
 	  goto done;
 	}
     }

   while (vec_len (pm->pcap_data) > pm->n_pcap_data_written)
     {
       int n = vec_len (pm->pcap_data) - pm->n_pcap_data_written;

       n = write (pm->file_descriptor,
 		 vec_elt_at_index (pm->pcap_data, pm->n_pcap_data_written),
 		 n);

       if (n < 0 && unix_error_is_fatal (errno))
 	{
 	  error = clib_error_return_unix (0, "write `%s'", pm->file_name);
 	  goto done;
 	}
       pm->n_pcap_data_written += n;
     }

   if (pm->n_pcap_data_written >= vec_len (pm->pcap_data))
     {
       vec_reset_length (pm->pcap_data);
       pm->n_pcap_data_written = 0;
     }

   if (pm->n_packets_captured >= pm->n_packets_to_capture)
     pcap_close (pm);

 done:
   if (error)
     {
       if (pm->file_descriptor >= 0)
 	close (pm->file_descriptor);
     }
   return error;
 }

 /**
  * @brief Read PCAP file
  *
  * @return rc - clib_error_t
  *
  */
 clib_error_t *
 pcap_read (pcap_main_t * pm)
 {
   clib_error_t *error = 0;
   int fd, need_swap, n;
   pcap_file_header_t fh;
   pcap_packet_header_t ph;

   fd = open (pm->file_name, O_RDONLY);
   if (fd < 0)
     {
       error = clib_error_return_unix (0, "open `%s'", pm->file_name);
       goto done;
     }

   if (read (fd, &fh, sizeof (fh)) != sizeof (fh))
     {
       error =
 	clib_error_return_unix (0, "read file header `%s'", pm->file_name);
       goto done;
     }

   need_swap = 0;
   if (fh.magic == 0xd4c3b2a1)
     {
       need_swap = 1;
 #define _(t,f) fh.f = clib_byte_swap_##t (fh.f);
       foreach_pcap_file_header;
 #undef _
     }

   if (fh.magic != 0xa1b2c3d4)
     {
       error = clib_error_return (0, "bad magic `%s'", pm->file_name);
       goto done;
     }

   pm->min_packet_bytes = 0;
   pm->max_packet_bytes = 0;
   while ((n = read (fd, &ph, sizeof (ph))) != 0)
     {
       u8 *data;
       u64 timestamp;
       u32 timestamp_sec;
       u32 timestamp_usec;

       if (need_swap)
 	{
 #define _(t,f) ph.f = clib_byte_swap_##t (ph.f);
 	  foreach_pcap_packet_header;
 #undef _
 	}

       data = vec_new (u8, ph.n_bytes_in_packet);
       if (read (fd, data, ph.n_packet_bytes_stored_in_file) !=
 	  ph.n_packet_bytes_stored_in_file)
 	{
 	  error = clib_error_return (0, "short read `%s'", pm->file_name);
 	  goto done;
 	}

       if (vec_len (pm->packets_read) == 0)
 	pm->min_packet_bytes = pm->max_packet_bytes = ph.n_bytes_in_packet;
       else
 	{
 	  pm->min_packet_bytes =
 	    clib_min (pm->min_packet_bytes, ph.n_bytes_in_packet);
 	  pm->max_packet_bytes =
 	    clib_max (pm->max_packet_bytes, ph.n_bytes_in_packet);
 	}

       timestamp_sec = ph.time_in_sec;
       timestamp_usec = ph.time_in_usec;
       timestamp = ((u64) timestamp_sec) * 1000000 + (u64) timestamp_usec;
       vec_add1 (pm->packets_read, data);
       vec_add1 (pm->timestamps, timestamp);
     }

 done:
   if (fd >= 0)
     close (fd);
   return error;

 }

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* Copyright (c) 2015 Cisco and/or its affiliates.
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at:
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	/*
	* pcap.c: libpcap packet capture format
	*
	* Copyright (c) 2008 Eliot Dresselhaus
	*
	* Permission is hereby granted, free of charge, to any person obtaining
	* a copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sublicense, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* The above copyright notice and this permission notice shall be
	* included in all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
	* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
	* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
	* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*/

	#include <vnet/unix/pcap.h>
	#include <sys/fcntl.h>

	/**
	* @file
	* @brief PCAP function.
	*
	* Usage:
	*
	* <code><pre>
	* \#include <vnet/unix/pcap.h>
	*
	* static pcap_main_t pcap = {
	* .file_name = "/tmp/ip4",
	* .n_packets_to_capture = 2,
	* .packet_type = PCAP_PACKET_TYPE_ip,
	* };
	* </pre></code>
	*
	* To add a buffer:
	*
	* <code><pre>pcap_add_buffer (&pcap, vm, pi0, 128);</pre></code>
	*
	* File will be written after @c n_packets_to_capture or call to pcap_write (&pcap).
	*
	*/

	/**
	* @brief Close PCAP file
	*
	* @return rc - clib_error_t
	*
	*/
	clib_error_t *
	pcap_close (pcap_main_t * pm)
	{
	close (pm->file_descriptor);
	pm->flags &= ~PCAP_MAIN_INIT_DONE;
	pm->file_descriptor = -1;
	return 0;
	}

	/**
	* @brief Write PCAP file
	*
	* @return rc - clib_error_t
	*
	*/
	clib_error_t *
	pcap_write (pcap_main_t * pm)
	{
	clib_error_t *error = 0;

	if (!(pm->flags & PCAP_MAIN_INIT_DONE))
	{
	pcap_file_header_t fh;
	int n;

	if (!pm->file_name)
	pm->file_name = "/tmp/vnet.pcap";

	pm->file_descriptor =
	open (pm->file_name, O_CREAT \| O_TRUNC \| O_WRONLY, 0664);
	if (pm->file_descriptor < 0)
	{
	error =
	clib_error_return_unix (0, "failed to open `%s'", pm->file_name);
	goto done;
	}

	pm->flags \|= PCAP_MAIN_INIT_DONE;
	pm->n_packets_captured = 0;
	pm->n_pcap_data_written = 0;

	/* Write file header. */
	memset (&fh, 0, sizeof (fh));
	fh.magic = 0xa1b2c3d4;
	fh.major_version = 2;
	fh.minor_version = 4;
	fh.time_zone = 0;
	fh.max_packet_size_in_bytes = 1 << 16;
	fh.packet_type = pm->packet_type;
	n = write (pm->file_descriptor, &fh, sizeof (fh));
	if (n != sizeof (fh))
	{
	if (n < 0)
	error =
	clib_error_return_unix (0, "write file header `%s'",
	pm->file_name);
	else
	error =
	clib_error_return (0, "short write of file header `%s'",
	pm->file_name);
	goto done;
	}
	}

	while (vec_len (pm->pcap_data) > pm->n_pcap_data_written)
	{
	int n = vec_len (pm->pcap_data) - pm->n_pcap_data_written;

	n = write (pm->file_descriptor,
	vec_elt_at_index (pm->pcap_data, pm->n_pcap_data_written),
	n);

	if (n < 0 && unix_error_is_fatal (errno))
	{
	error = clib_error_return_unix (0, "write `%s'", pm->file_name);
	goto done;
	}
	pm->n_pcap_data_written += n;
	}

	if (pm->n_pcap_data_written >= vec_len (pm->pcap_data))
	{
	vec_reset_length (pm->pcap_data);
	pm->n_pcap_data_written = 0;
	}

	if (pm->n_packets_captured >= pm->n_packets_to_capture)
	pcap_close (pm);

	done:
	if (error)
	{
	if (pm->file_descriptor >= 0)
	close (pm->file_descriptor);
	}
	return error;
	}

	/**
	* @brief Read PCAP file
	*
	* @return rc - clib_error_t
	*
	*/
	clib_error_t *
	pcap_read (pcap_main_t * pm)
	{
	clib_error_t *error = 0;
	int fd, need_swap, n;
	pcap_file_header_t fh;
	pcap_packet_header_t ph;

	fd = open (pm->file_name, O_RDONLY);
	if (fd < 0)
	{
	error = clib_error_return_unix (0, "open `%s'", pm->file_name);
	goto done;
	}

	if (read (fd, &fh, sizeof (fh)) != sizeof (fh))
	{
	error =
	clib_error_return_unix (0, "read file header `%s'", pm->file_name);
	goto done;
	}

	need_swap = 0;
	if (fh.magic == 0xd4c3b2a1)
	{
	need_swap = 1;
	#define _(t,f) fh.f = clib_byte_swap_##t (fh.f);
	foreach_pcap_file_header;
	#undef _
	}

	if (fh.magic != 0xa1b2c3d4)
	{
	error = clib_error_return (0, "bad magic `%s'", pm->file_name);
	goto done;
	}

	pm->min_packet_bytes = 0;
	pm->max_packet_bytes = 0;
	while ((n = read (fd, &ph, sizeof (ph))) != 0)
	{
	u8 *data;
	u64 timestamp;
	u32 timestamp_sec;
	u32 timestamp_usec;

	if (need_swap)
	{
	#define _(t,f) ph.f = clib_byte_swap_##t (ph.f);
	foreach_pcap_packet_header;
	#undef _
	}

	data = vec_new (u8, ph.n_bytes_in_packet);
	if (read (fd, data, ph.n_packet_bytes_stored_in_file) !=
	ph.n_packet_bytes_stored_in_file)
	{
	error = clib_error_return (0, "short read `%s'", pm->file_name);
	goto done;
	}

	if (vec_len (pm->packets_read) == 0)
	pm->min_packet_bytes = pm->max_packet_bytes = ph.n_bytes_in_packet;
	else
	{
	pm->min_packet_bytes =
	clib_min (pm->min_packet_bytes, ph.n_bytes_in_packet);
	pm->max_packet_bytes =
	clib_max (pm->max_packet_bytes, ph.n_bytes_in_packet);
	}

	timestamp_sec = ph.time_in_sec;
	timestamp_usec = ph.time_in_usec;
	timestamp = ((u64) timestamp_sec) * 1000000 + (u64) timestamp_usec;
	vec_add1 (pm->packets_read, data);
	vec_add1 (pm->timestamps, timestamp);
	}

	done:
	if (fd >= 0)
	close (fd);
	return error;

	}

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/