dns_test.c

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/*
 * Copyright (C) 2014 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 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
 *
 * DNS self-tests
 *
 */

/* Forcibly enable assertions */
#undef NDEBUG

#include <string.h>
#include <assert.h>
#include <ipxe/dns.h>
#include <ipxe/test.h>

/** Define inline data */
#define DATA(...) { __VA_ARGS__ }

/** A DNS encoding test */
struct dns_encode_test {
        /** String */
        const char *string;
        /** Encoded string */
        const void *data;
        /** Length of encoded string */
        int len;
};

/**
 * Define a DNS encoding test
 *
 * @v _name             Test name
 * @v _string           Test string
 * @v _data             Expected encoded data
 * @ret test            DNS encoding test
 */
#define DNS_ENCODE( _name, _string, _data )                             \
        static const uint8_t _name ## __data[] = _data;                 \
        static struct dns_encode_test _name = {                         \
                .string = _string,                                      \
                .data = _name ## __data,                                \
                .len = sizeof ( _name ## __data ),                      \
        }

/**
 * Report DNS encoding test result
 *
 * @v test              DNS encoding test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_encode_okx ( struct dns_encode_test *test, const char *file,
                             unsigned int line ) {
        uint8_t data[ test->len ];
        struct dns_name name;
        int len;

        /* Check ability to determine length with no buffer */
        memset ( &name, 0, sizeof ( name ) );
        len = dns_encode ( test->string, &name );
        okx ( len >= 0, file, line );
        okx ( len == test->len, file, line );

        /* Check encoded name */
        name.data = data;
        name.len = sizeof ( data );
        len = dns_encode ( test->string, &name );
        okx ( len >= 0, file, line );
        if ( len >= 0 ) {
                okx ( len == test->len, file, line );
                okx ( memcmp ( data, test->data, test->len ) == 0, file, line );
                DBGC ( test, "DNS encoded \"%s\" to:\n", test->string );
                DBGC_HDA ( test, 0, data, len );
        }
}
#define dns_encode_ok( test ) dns_encode_okx ( test, __FILE__, __LINE__ )

/**
 * Report DNS encoding failure test result
 *
 * @v test              DNS encoding test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_encode_fail_okx ( struct dns_encode_test *test,
                                  const char *file, unsigned int line ) {
        struct dns_name name = { .data = NULL, .len = 0 };
        int len;

        len = dns_encode ( test->string, &name );
        okx ( len < 0, file, line );
}
#define dns_encode_fail_ok( test ) \
        dns_encode_fail_okx ( test, __FILE__, __LINE__ )

/** A DNS decoding test */
struct dns_decode_test {
        /** Name */
        struct dns_name name;
        /** Expected string */
        const char *string;
};

/**
 * Define a DNS decoding test
 *
 * @v _name             Test name
 * @v _data             RFC1035-encoded data
 * @v _offset           Starting offset within encoded data
 * @v _string           Expected decoded string
 * @ret test            DNS decoding test
 */
#define DNS_DECODE( _name, _data, _offset, _string )                    \
        static uint8_t _name ## __data[] = _data;                       \
        static struct dns_decode_test _name = {                         \
                .name = {                                               \
                        .data = _name ## __data,                        \
                        .offset = _offset,                              \
                        .len = sizeof ( _name ## __data ),              \
                },                                                      \
                .string = _string,                                      \
        }

/**
 * Report DNS decoding test result
 *
 * @v test              DNS decoding test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_decode_okx ( struct dns_decode_test *test, const char *file,
                             unsigned int line ) {
        char string[ strlen ( test->string ) + 1 /* NUL */ ];
        int len;

        /* Check ability to determine length with no buffer */
        len = dns_decode ( &test->name, NULL, 0 );
        okx ( len >= 0, file, line );
        okx ( len == ( ( int ) strlen ( test->string ) ), file, line );

        /* Check decoded string */
        len = dns_decode ( &test->name, string, sizeof ( string ) );
        okx ( len >= 0, file, line );
        if ( len >= 0 ) {
                okx ( strcmp ( string, test->string ) == 0, file, line );
                DBGC ( test, "DNS decoded \"%s\" from offset %#zx in:\n",
                       string, test->name.offset );
                DBGC_HDA ( test, 0, test->name.data, test->name.len );
        }
}
#define dns_decode_ok( test ) dns_decode_okx ( test, __FILE__, __LINE__ )

/**
 * Report DNS decoding failure test result
 *
 * @v test              DNS decoding test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_decode_fail_okx ( struct dns_decode_test *test,
                                  const char *file, unsigned int line ) {
        int len;

        len = dns_decode ( &test->name, NULL, 0 );
        okx ( len < 0, file, line );
}
#define dns_decode_fail_ok( test ) \
        dns_decode_fail_okx ( test, __FILE__, __LINE__ )

/** A DNS comparison test */
struct dns_compare_test {
        /** First name */
        struct dns_name first;
        /** Second name */
        struct dns_name second;
};

/**
 * Define a DNS comparison test
 *
 * @v _name             Test name
 * @v _first_data       First RFC1035-encoded data
 * @v _first_offset     Starting offset within first encoded data
 * @v _second_data      Second RFC1035-encoded data
 * @v _second_offset    Starting offset within second encoded data
 * @ret test            DNS comparison test
 */
#define DNS_COMPARE( _name, _first_data, _first_offset, _second_data,   \
                     _second_offset )                                   \
        static uint8_t _name ## __first_data[] = _first_data;           \
        static uint8_t _name ## __second_data[] = _second_data;         \
        static struct dns_compare_test _name = {                        \
                .first = {                                              \
                        .data = _name ## __first_data,                  \
                        .offset = _first_offset,                        \
                        .len = sizeof ( _name ## __first_data ),        \
                },                                                      \
                .second = {                                             \
                        .data = _name ## __second_data,                 \
                        .offset = _second_offset,                       \
                        .len = sizeof ( _name ## __second_data ),       \
                },                                                      \
        }

/**
 * Report DNS comparison test result
 *
 * @v test              DNS comparison test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_compare_okx ( struct dns_compare_test *test, const char *file,
                              unsigned int line ) {

        okx ( dns_compare ( &test->first, &test->second ) == 0, file, line );
}
#define dns_compare_ok( test ) dns_compare_okx ( test, __FILE__, __LINE__ )

/**
 * Report DNS comparison test failure result
 *
 * @v test              DNS comparison test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_compare_fail_okx ( struct dns_compare_test *test,
                                   const char *file, unsigned int line ) {

        okx ( dns_compare ( &test->first, &test->second ) != 0, file, line );
}
#define dns_compare_fail_ok( test ) \
        dns_compare_fail_okx ( test, __FILE__, __LINE__ )

/** A DNS copying test */
struct dns_copy_test {
        /** Source name */
        struct dns_name src;
        /** Expected copied name */
        struct dns_name dst;
};

/**
 * Define a DNS copying test
 *
 * @v _name             Test name
 * @v _src_data         Source RFC1035-encoded data
 * @v _src_offset       Starting offset within source encoded data
 * @v _dst_data         Expected copied RFC1035-encoded data
 * @v _dst_offset       Starting offset withint copied encoded data
 * @ret test            DNS copying test
 */
#define DNS_COPY( _name, _src_data, _src_offset, _dst_data,             \
                  _dst_offset )                                         \
        static uint8_t _name ## __src_data[] = _src_data;               \
        static uint8_t _name ## __dst_data[] = _dst_data;               \
        static struct dns_copy_test _name = {                           \
                .src = {                                                \
                        .data = _name ## __src_data,                    \
                        .offset = _src_offset,                          \
                        .len = sizeof ( _name ## __src_data ),          \
                },                                                      \
                .dst = {                                                \
                        .data = _name ## __dst_data,                    \
                        .offset = _dst_offset,                          \
                        .len = sizeof ( _name ## __dst_data ),          \
                },                                                      \
        }

/**
 * Report a DNS copying test result
 *
 * @v test              DNS copying test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_copy_okx ( struct dns_copy_test *test,
                           const char *file, unsigned int line ) {
        uint8_t data[ test->dst.len ];
        struct dns_name dst;
        int len;

        /* Check ability to determine length with no buffer */
        memset ( &dst, 0, sizeof ( dst ) );
        len = dns_copy ( &test->src, &dst );
        okx ( len >= 0, file, line );
        okx ( len == ( ( int ) ( test->dst.len - test->dst.offset ) ),
              file, line );

        /* Check copied name */
        dst.data = data;
        dst.offset = test->dst.offset;
        dst.len = sizeof ( data );
        memcpy ( dst.data, test->dst.data, test->dst.offset );
        len = dns_copy ( &test->src, &dst );
        okx ( len >= 0, file, line );
        okx ( len == ( ( int ) ( test->dst.len - test->dst.offset ) ),
              file, line );
        okx ( memcmp ( data, test->dst.data, sizeof ( data ) ) == 0,
              file, line );
        DBGC ( test, "DNS copied:\n" );
        DBGC_HDA ( test, 0, test->src.data, test->src.len );
        DBGC_HDA ( test, 0, data, ( test->dst.offset + len ) );
}
#define dns_copy_ok( test ) dns_copy_okx ( test, __FILE__, __LINE__ )

/**
 * Report a DNS copying failure test result
 *
 * @v test              DNS copying test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_copy_fail_okx ( struct dns_copy_test *test,
                                const char *file, unsigned int line ) {
        struct dns_name dst;
        int len;

        memset ( &dst, 0, sizeof ( dst ) );
        len = dns_copy ( &test->src, &dst );
        okx ( len < 0, file, line );
}
#define dns_copy_fail_ok( test ) dns_copy_fail_okx ( test, __FILE__, __LINE__ )

/** A DNS search list test */
struct dns_list_test {
        /** Search list */
        struct dns_name list;
        /** Expected decoded search list */
        const char **strings;
        /** Number of expected decoded string */
        unsigned int count;
};

/**
 * Define a DNS search list test
 *
 * @v _name             Test name
 * @v _list             RFC1035-encoded data
 * @v _strings          Expected decoded strings
 * @ret test            DNS search list test
 */
#define DNS_LIST( _name, _list, _strings )                              \
        static uint8_t _name ## __list[] = _list;                       \
        static const char * _name ## __strings[] = _strings;            \
        static struct dns_list_test _name = {                           \
                .list = {                                               \
                        .data = _name ## __list,                        \
                        .offset = 0,                                    \
                        .len = sizeof ( _name ## __list ),              \
                },                                                      \
                .strings = _name ## __strings,                          \
                .count = ( sizeof ( _name ## __strings ) /              \
                           sizeof ( _name ## __strings[0] ) ),          \
        }

/**
 * Report DNS search list test result
 *
 * @v test              DNS search list test
 * @v file              Test code file
 * @v line              Test code line
 */
static void dns_list_okx ( struct dns_list_test *test, const char *file,
                           unsigned int line ) {
        struct dns_name name;
        unsigned int i;

        DBGC ( test, "DNS search list:\n" );
        DBGC_HDA ( test, 0, test->list.data, test->list.len );
        memcpy ( &name, &test->list, sizeof ( name ) );
        for ( i = 0 ; i < test->count ; i++ ) {
                char buf[ strlen ( test->strings[i] ) + 1 /* NUL */ ];
                int len;
                int offset;

                /* Decode this name */
                len = dns_decode ( &name, buf, sizeof ( buf ) );
                okx ( len >= 0, file, line );
                if ( len >= 0 ) {
                        okx ( len == ( ( int ) strlen ( test->strings[i] ) ),
                              file, line );
                        okx ( strcmp ( buf, test->strings[i] ) == 0,
                              file, line );
                        DBGC ( test, "DNS search list found \"%s\" at offset "
                               "%#zx\n", buf, name.offset );
                }

                /* Skip to next name */
                offset = dns_skip ( &name );
                okx ( offset >= 0, file, line );
                name.offset = offset;
        }

        /* Check that we have consumed the whole search list */
        okx ( name.offset == name.len, file, line );
}
#define dns_list_ok( test ) dns_list_okx ( test, __FILE__, __LINE__ )

/* Simple encoding test */
DNS_ENCODE ( encode_simple, "ipxe.org",
             DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ) );

/* Single-word encoding test */
DNS_ENCODE ( encode_single, "foo", DATA ( 3, 'f', 'o', 'o', 0 ) );

/* Absolute encoding test */
DNS_ENCODE ( encode_absolute, "git.ipxe.org.",
             DATA ( 3, 'g', 'i', 't', 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g',
                    0 ) );

/* Empty string encoding test */
DNS_ENCODE ( encode_empty, "", DATA ( 0 ) );

/* Root domain encoding test */
DNS_ENCODE ( encode_root, ".", DATA ( 0 ) );

/* Invalid initial dot encoding test */
DNS_ENCODE ( encode_initial_dot, ".foo", DATA() );

/* Invalid double dot encoding test */
DNS_ENCODE ( encode_double_dot, "ipxe..org", DATA() );

/* Invalid solo double dot encoding test */
DNS_ENCODE ( encode_solo_double_dot, "..", DATA() );

/* Invalid trailing double dot encoding test */
DNS_ENCODE ( encode_trailing_double_dot, "ipxe.org..", DATA() );

/* Invalid overlength label encoding test */
DNS_ENCODE ( encode_overlength,
             "this-label-is-maliciously-long-in-an-attempt-to-overflow-the-"
             "length-field-and-generate-a-length-which-looks-like-a-"
             "compression-pointer", DATA() );

/* Simple decoding test */
DNS_DECODE ( decode_simple,
             DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
             "ipxe.org" );

/* Compression pointer decoding test */
DNS_DECODE ( decode_ptr,
             DATA ( 3, 'o', 'r', 'g', 0, 3, 'g', 'i', 't', 4, 'i', 'p', 'x',
                    'e', 0xc0, 0x00 ), 5,
             "git.ipxe.org" );

/* Root decoding test */
DNS_DECODE ( decode_root,
             DATA ( 0 ), 0, "" );

/* Incomplete name decoding test */
DNS_DECODE ( decode_incomplete_name,
             DATA ( 4, 'i', 'p', 'x', 'e' ), 0, NULL );

/* Incomplete label decoding test */
DNS_DECODE ( decode_incomplete_label,
             DATA ( 4, 'i', 'p', 'x' ), 0, NULL );

/* Incomplete compression pointer decoding test */
DNS_DECODE ( decode_incomplete_ptr,
             DATA ( 3, 'o', 'r', 'g', 0, 4, 'i', 'p', 'x', 'e', 0xc0 ), 5,
             NULL );

/* Forward reference decoding test */
DNS_DECODE ( decode_forward,
             DATA ( 0xc0, 0x02, 3, 'f', 'o', 'o', 0 ), 0, NULL );

/* Infinite loop decoding test */
DNS_DECODE ( decode_infinite,
             DATA ( 4, 'i', 'p', 'x', 'e', 0xc0, 0x00 ), 0, NULL );

/* Empty decoding test */
DNS_DECODE ( decode_empty,
             DATA (), 0, NULL );

/* Simple comparison test */
DNS_COMPARE ( compare_simple,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0 );

/* Compression pointer comparison test */
DNS_COMPARE ( compare_ptr,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
              DATA ( 3, 'o', 'r', 'g', 0, 4, 'i', 'p', 'x', 'e',
                     0xc0, 0x00 ), 5 );

/* Case insensitive comparison test */
DNS_COMPARE ( compare_case,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'O', 'R', 'G', 0 ), 0 );

/* Mismatch comparison test */
DNS_COMPARE ( compare_mismatch,
              DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
              DATA ( 4, 'g', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0 );

/* Infinite loop comparison test */
DNS_COMPARE ( compare_infinite,
              DATA ( 3, 'f', 'o', 'o', 0xc0, 0x00 ), 0,
              DATA ( 3, 'f', 'o', 'o', 0xc0, 0x00 ), 0 );

/* Simple copying test */
DNS_COPY ( copy_simple,
           DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
           DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0 );

/* Simple copying test with offset */
DNS_COPY ( copy_offset,
           DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0 ), 0,
           DATA ( 'f', 'o', 'o', 0, 4, 'i', 'p', 'x', 'e',
                  3, 'o', 'r', 'g', 0 ), 4 );

/* Compression pointer copying test */
DNS_COPY ( copy_ptr,
           DATA ( 3, 'o', 'r', 'g', 0, 3, 'g', 'i', 't', 4, 'i', 'p', 'x', 'e',
                  0xc0, 0x00 ), 5,
           DATA ( 3, 'g', 'i', 't', 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g',
                  0 ), 0 );

/* Infinite loop copying test */
DNS_COPY ( copy_infinite,
           DATA ( 4, 'l', 'o', 'o', 'p', 7, 'f', 'o', 'r', 'e', 'v', 'e', 'r',
                  0xc0, 0x05 ), 0,
           DATA (), 0 );

/* DNS search list test */
DNS_LIST ( search,
           DATA ( 4, 'i', 'p', 'x', 'e', 3, 'o', 'r', 'g', 0,
                  4, 'b', 'o', 'o', 't', 0xc0, 0x00,
                  3, 'd', 'e', 'v', 0xc0, 0x0a,
                  11, 'n', 'e', 't', 'w', 'o', 'r', 'k', 'b', 'o', 'o', 't',
                  0xc0, 0x05 ),
           DATA ( "ipxe.org", "boot.ipxe.org", "dev.boot.ipxe.org",
                  "networkboot.org" ) );

/**
 * Perform DNS self-test
 *
 */
static void dns_test_exec ( void ) {

        /* Encoding tests */
        dns_encode_ok ( &encode_simple );
        dns_encode_ok ( &encode_single );
        dns_encode_ok ( &encode_absolute );
        dns_encode_ok ( &encode_empty );
        dns_encode_ok ( &encode_root );
        dns_encode_fail_ok ( &encode_initial_dot );
        dns_encode_fail_ok ( &encode_double_dot );
        dns_encode_fail_ok ( &encode_solo_double_dot );
        dns_encode_fail_ok ( &encode_trailing_double_dot );
        dns_encode_fail_ok ( &encode_overlength );

        /* Decoding tests */
        dns_decode_ok ( &decode_simple );
        dns_decode_ok ( &decode_ptr );
        dns_decode_ok ( &decode_root );
        dns_decode_fail_ok ( &decode_incomplete_name );
        dns_decode_fail_ok ( &decode_incomplete_label );
        dns_decode_fail_ok ( &decode_incomplete_ptr );
        dns_decode_fail_ok ( &decode_forward );
        dns_decode_fail_ok ( &decode_infinite );
        dns_decode_fail_ok ( &decode_empty );

        /* Comparison tests */
        dns_compare_ok ( &compare_simple );
        dns_compare_ok ( &compare_ptr );
        dns_compare_ok ( &compare_case );
        dns_compare_fail_ok ( &compare_mismatch );
        dns_compare_fail_ok ( &compare_infinite );

        /* Copying tests */
        dns_copy_ok ( &copy_simple );
        dns_copy_ok ( &copy_offset );
        dns_copy_ok ( &copy_ptr );
        dns_copy_fail_ok ( &copy_infinite );

        /* Search list tets */
        dns_list_ok ( &search );
}

/** DNS self-test */
struct self_test dns_test __self_test = {
        .name = "dns",
        .exec = dns_test_exec,
};