text: /*
   * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
   *
   * This program 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 2 of the
   * License, or (at your option) any later version.
   *
   * 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; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   * 02110-1301, USA.
   *
   * You can also choose to distribute this program under the terms of
   * the Unmodified Binary Distribution Licence (as given in the file
   * COPYING.UBDL), provided that you have satisfied its requirements.
   */
  
  FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  
  /** @file
   *
   * TCP/IP self-tests
   *
   */
  
  /* Forcibly enable assertions */
  #undef NDEBUG
  
  #include <stdint.h>
  #include <stdlib.h>
  #include <string.h>
  #include <assert.h>
  #include <ipxe/test.h>
  #include <ipxe/profile.h>
  #include <ipxe/tcpip.h>
  
  /** Number of sample iterations for profiling */
  #define PROFILE_COUNT 16
  
  /** A TCP/IP fixed-data test */
  struct tcpip_test {
  	/** Data */
  	const void *data;
  	/** Length of data */
  	size_t len;
  };
  
  /** A TCP/IP pseudorandom-data test */
  struct tcpip_random_test {
  	/** Seed */
  	unsigned int seed;
  	/** Length of data */
  	size_t len;
  	/** Alignment offset */
  	size_t offset;
  };
  
  /** Define inline data */
  #define DATA(...) { __VA_ARGS__ }
  
  /** Define a TCP/IP fixed-data test */
  #define TCPIP_TEST( name, DATA )					\
  	static const uint8_t __attribute__ (( aligned ( 16 ) ))		\
  		name ## _data[] = DATA;					\
  	static struct tcpip_test name = {				\
  		.data = name ## _data,					\
  		.len = sizeof ( name ## _data ),			\
  	}
  
  /** Define a TCP/IP pseudorandom-data test */
  #define TCPIP_RANDOM_TEST( name, SEED, LEN, OFFSET )			\
  	static struct tcpip_random_test name = {			\
  		.seed = SEED,						\
  		.len = LEN,						\
  		.offset = OFFSET,					\
  	}
  
  /** Buffer for pseudorandom-data tests */
  static uint8_t __attribute__ (( aligned ( 16 ) ))
  	tcpip_data[ 4096 + 7 /* offset */ ];
  
  /** Empty data */
  TCPIP_TEST ( empty, DATA() );
  
  /** Single byte */
  TCPIP_TEST ( one_byte, DATA ( 0xeb ) );
  
  /** Double byte */
  TCPIP_TEST ( two_bytes, DATA ( 0xba, 0xbe ) );
  
  /** Positive zero data */
  TCPIP_TEST ( positive_zero, DATA ( 0x00, 0x00 ) );
  
  /** Negative zero data */
  TCPIP_TEST ( negative_zero, DATA ( 0xff, 0xff ) );
  
  /** Final wrap-around carry (big-endian) */
  TCPIP_TEST ( final_carry_big,
  	     DATA ( 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 ) );
  
  /** Final wrap-around carry (little-endian) */
  TCPIP_TEST ( final_carry_little,
  	     DATA ( 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00 ) );
  
  /** Random data (aligned) */
  TCPIP_RANDOM_TEST ( random_aligned, 0x12345678UL, 4096, 0 );
  
  /** Random data (unaligned, +1) */
  TCPIP_RANDOM_TEST ( random_unaligned_1, 0x12345678UL, 4096, 1 );
  
  /** Random data (unaligned, +2) */
  TCPIP_RANDOM_TEST ( random_unaligned_2, 0x12345678UL, 4096, 2 );
  
  /** Random data (aligned, truncated) */
  TCPIP_RANDOM_TEST ( random_aligned_truncated, 0x12345678UL, 4095, 0 );
  
  /** Random data (unaligned start and finish) */
  TCPIP_RANDOM_TEST ( partial, 0xcafebabe, 121, 5 );
  
  /**
   * Calculate TCP/IP checksum
   *
   * @v data		Data to sum
   * @v len		Length of data
   * @ret cksum		Checksum
   *
   * This is a reference implementation taken from RFC1071 (and modified
   * to fix compilation without warnings under gcc).
   *
   * The initial value of the one's complement @c sum is changed from
   * positive zero (0x0000) to negative zero (0xffff).  This ensures
   * that the return value will always use the positive representation
   * of zero (0x0000).  Without this change, the return value would use
   * negative zero (0xffff) if the input data is zero length (or all
   * zeros) but positive zero (0x0000) for any other data which sums to
   * zero.
   */
  static uint16_t rfc_tcpip_chksum ( const void *data, size_t len ) {
  	unsigned long sum = 0xffff;
  
          while ( len > 1 )  {
  		sum += *( ( uint16_t * ) data );
  		data += 2;
  		len -= 2;
  	}
  
  	if ( len > 0 )
  		sum += *( ( uint8_t * ) data );
  
  	while ( sum >> 16 )
  		sum = ( ( sum & 0xffff ) + ( sum >> 16 ) );
  
  	assert ( sum != 0x0000 );
  	return ~sum;
  }
  
  /**
   * Report TCP/IP fixed-data test result
   *
   * @v test		TCP/IP test
   * @v file		Test code file
   * @v line		Test code line
   */
  static void tcpip_okx ( struct tcpip_test *test, const char *file,
  			unsigned int line ) {
  	uint16_t expected;
  	uint16_t generic_sum;
  	uint16_t sum;
  
  	/* Verify generic_tcpip_continue_chksum() result */
  	expected = rfc_tcpip_chksum ( test->data, test->len );
  	generic_sum = generic_tcpip_continue_chksum ( TCPIP_EMPTY_CSUM,
  						      test->data, test->len );
  	okx ( generic_sum == expected, file, line );
  
  	/* Verify optimised tcpip_continue_chksum() result */
  	sum = tcpip_continue_chksum ( TCPIP_EMPTY_CSUM, test->data, test->len );
  	okx ( sum == expected, file, line );
  }
  #define tcpip_ok( test ) tcpip_okx ( test, __FILE__, __LINE__ )
  
  /**
   * Report TCP/IP pseudorandom-data test result
   *
   * @v test		TCP/IP test
   * @v file		Test code file
   * @v line		Test code line
   */
  static void tcpip_random_okx ( struct tcpip_random_test *test,
  			       const char *file, unsigned int line ) {
  	uint8_t *data = ( tcpip_data + test->offset );
  	struct profiler profiler;
  	uint16_t expected;
  	uint16_t generic_sum;
  	uint16_t sum;
  	unsigned int i;
  
  	/* Sanity check */
  	assert ( ( test->len + test->offset ) <= sizeof ( tcpip_data ) );
  
  	/* Generate random data */
  	srandom ( test->seed );
  	for ( i = 0 ; i < test->len ; i++ )
  		data[i] = random();
  
  	/* Verify generic_tcpip_continue_chksum() result */
  	expected = rfc_tcpip_chksum ( data, test->len );
  	generic_sum = generic_tcpip_continue_chksum ( TCPIP_EMPTY_CSUM,
  						      data, test->len );
  	okx ( generic_sum == expected, file, line );
  
  	/* Verify optimised tcpip_continue_chksum() result */
  	sum = tcpip_continue_chksum ( TCPIP_EMPTY_CSUM, data, test->len );
  	okx ( sum == expected, file, line );
  
  	/* Profile optimised calculation */
  	memset ( &profiler, 0, sizeof ( profiler ) );
  	for ( i = 0 ; i < PROFILE_COUNT ; i++ ) {
  		profile_start ( &profiler );
  		sum = tcpip_continue_chksum ( TCPIP_EMPTY_CSUM, data,
  					      test->len );
  		profile_stop ( &profiler );
  	}
  	DBG ( "TCPIP checksummed %zd bytes (+%zd) in %ld +/- %ld ticks\n",
  	      test->len, test->offset, profile_mean ( &profiler ),
  	      profile_stddev ( &profiler ) );
  }
  #define tcpip_random_ok( test ) tcpip_random_okx ( test, __FILE__, __LINE__ )
  
  /**
   * Perform TCP/IP self-tests
   *
   */
  static void tcpip_test_exec ( void ) {
  
  	tcpip_ok ( &empty );
  	tcpip_ok ( &one_byte );
  	tcpip_ok ( &two_bytes );
  	tcpip_ok ( &positive_zero );
  	tcpip_ok ( &negative_zero );
  	tcpip_ok ( &final_carry_big );
  	tcpip_ok ( &final_carry_little );
  	tcpip_random_ok ( &random_aligned );
  	tcpip_random_ok ( &random_unaligned_1 );
  	tcpip_random_ok ( &random_unaligned_2 );
  	tcpip_random_ok ( &random_aligned_truncated );
  	tcpip_random_ok ( &partial );
  }
  
  /** TCP/IP self-test */
  struct self_test tcpip_test __self_test = {
  	.name = "tcpip",
  	.exec = tcpip_test_exec,
  };
  