lib/test_hexdump.c

   1 /*
   2  * Test cases for lib/hexdump.c module.
   3  */
   4 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   5
   6 #include <linux/init.h>
   7 #include <linux/kernel.h>
   8 #include <linux/module.h>
   9 #include <linux/random.h>
  10 #include <linux/string.h>
  11
  12 static const unsigned char data_b[] = {
  13         '\xbe', '\x32', '\xdb', '\x7b', '\x0a', '\x18', '\x93', '\xb2', /* 00 - 07 */
  14         '\x70', '\xba', '\xc4', '\x24', '\x7d', '\x83', '\x34', '\x9b', /* 08 - 0f */
  15         '\xa6', '\x9c', '\x31', '\xad', '\x9c', '\x0f', '\xac', '\xe9', /* 10 - 17 */
  16         '\x4c', '\xd1', '\x19', '\x99', '\x43', '\xb1', '\xaf', '\x0c', /* 18 - 1f */
  17 };
  18
  19 static const unsigned char data_a[] = ".2.{....p..$}.4...1.....L...C...";
  20
  21 static const char * const test_data_1_le[] __initconst = {
  22         "be", "32", "db", "7b", "0a", "18", "93", "b2",
  23         "70", "ba", "c4", "24", "7d", "83", "34", "9b",
  24         "a6", "9c", "31", "ad", "9c", "0f", "ac", "e9",
  25         "4c", "d1", "19", "99", "43", "b1", "af", "0c",
  26 };
  27
  28 static const char * const test_data_2_le[] __initconst = {
  29         "32be", "7bdb", "180a", "b293",
  30         "ba70", "24c4", "837d", "9b34",
  31         "9ca6", "ad31", "0f9c", "e9ac",
  32         "d14c", "9919", "b143", "0caf",
  33 };
  34
  35 static const char * const test_data_4_le[] __initconst = {
  36         "7bdb32be", "b293180a", "24c4ba70", "9b34837d",
  37         "ad319ca6", "e9ac0f9c", "9919d14c", "0cafb143",
  38 };
  39
  40 static const char * const test_data_8_le[] __initconst = {
  41         "b293180a7bdb32be", "9b34837d24c4ba70",
  42         "e9ac0f9cad319ca6", "0cafb1439919d14c",
  43 };
  44
  45 #define FILL_CHAR       '#'
  46
  47 static void __init test_hexdump_prepare_test(size_t len, int rowsize,
  48                                              int groupsize, char *test,
  49                                              size_t testlen, bool ascii)
  50 {
  51         char *p;
  52         const char * const *result;
  53         size_t l = len;
  54         int gs = groupsize, rs = rowsize;
  55         unsigned int i;
  56
  57         if (rs != 16 && rs != 32)
  58                 rs = 16;
  59
  60         if (l > rs)
  61                 l = rs;
  62
  63         if (!is_power_of_2(gs) || gs > 8 || (len % gs != 0))
  64                 gs = 1;
  65
  66         if (gs == 8)
  67                 result = test_data_8_le;
  68         else if (gs == 4)
  69                 result = test_data_4_le;
  70         else if (gs == 2)
  71                 result = test_data_2_le;
  72         else
  73                 result = test_data_1_le;
  74
  75         /* hex dump */
  76         p = test;
  77         for (i = 0; i < l / gs; i++) {
  78                 const char *q = *result++;
  79                 size_t amount = strlen(q);
  80
  81                 strncpy(p, q, amount);
  82                 p += amount;
  83
  84                 *p++ = ' ';
  85         }
  86         if (i)
  87                 p--;
  88
  89         /* ASCII part */
  90         if (ascii) {
  91                 do {
  92                         *p++ = ' ';
  93                 } while (p < test + rs * 2 + rs / gs + 1);
  94
  95                 strncpy(p, data_a, l);
  96                 p += l;
  97         }
  98
  99         *p = '\0';
 100 }
 101
 102 #define TEST_HEXDUMP_BUF_SIZE           (32 * 3 + 2 + 32 + 1)
 103
 104 static void __init test_hexdump(size_t len, int rowsize, int groupsize,
 105                                 bool ascii)
 106 {
 107         char test[TEST_HEXDUMP_BUF_SIZE];
 108         char real[TEST_HEXDUMP_BUF_SIZE];
 109
 110         memset(real, FILL_CHAR, sizeof(real));
 111         hex_dump_to_buffer(data_b, len, rowsize, groupsize, real, sizeof(real),
 112                            ascii);
 113
 114         memset(test, FILL_CHAR, sizeof(test));
 115         test_hexdump_prepare_test(len, rowsize, groupsize, test, sizeof(test),
 116                                   ascii);
 117
 118         if (memcmp(test, real, TEST_HEXDUMP_BUF_SIZE)) {
 119                 pr_err("Len: %zu row: %d group: %d\n", len, rowsize, groupsize);
 120                 pr_err("Result: '%s'\n", real);
 121                 pr_err("Expect: '%s'\n", test);
 122         }
 123 }
 124
 125 static void __init test_hexdump_set(int rowsize, bool ascii)
 126 {
 127         size_t d = min_t(size_t, sizeof(data_b), rowsize);
 128         size_t len = get_random_int() % d + 1;
 129
 130         test_hexdump(len, rowsize, 4, ascii);
 131         test_hexdump(len, rowsize, 2, ascii);
 132         test_hexdump(len, rowsize, 8, ascii);
 133         test_hexdump(len, rowsize, 1, ascii);
 134 }
 135
 136 static void __init test_hexdump_overflow(size_t buflen, bool ascii)
 137 {
 138         char buf[TEST_HEXDUMP_BUF_SIZE];
 139         const char *t = test_data_1_le[0];
 140         size_t len = 1;
 141         int rs = 16, gs = 1;
 142         int ae, he, e, r;
 143         bool a;
 144
 145         memset(buf, FILL_CHAR, sizeof(buf));
 146
 147         r = hex_dump_to_buffer(data_b, len, rs, gs, buf, buflen, ascii);
 148
 149         /*
 150          * Caller must provide the data length multiple of groupsize. The
 151          * calculations below are made with that assumption in mind.
 152          */
 153         ae = rs * 2 /* hex */ + rs / gs /* spaces */ + 1 /* space */ + len /* ascii */;
 154         he = (gs * 2 /* hex */ + 1 /* space */) * len / gs - 1 /* no trailing space */;
 155
 156         if (ascii)
 157                 e = ae;
 158         else
 159                 e = he;
 160         buf[e + 2] = '\0';
 161
 162         if (!buflen) {
 163                 a = r == e && buf[0] == FILL_CHAR;
 164         } else if (buflen < 3) {
 165                 a = r == e && buf[0] == '\0';
 166         } else if (buflen < 4) {
 167                 a = r == e && !strcmp(buf, t);
 168         } else if (ascii) {
 169                 if (buflen < 51)
 170                         a = r == e && buf[buflen - 1] == '\0' && buf[buflen - 2] == FILL_CHAR;
 171                 else
 172                         a = r == e && buf[50] == '\0' && buf[49] == '.';
 173         } else {
 174                 a = r == e && buf[e] == '\0';
 175         }
 176
 177         if (!a) {
 178                 pr_err("Len: %zu rc: %u strlen: %zu\n", buflen, r, strlen(buf));
 179                 pr_err("Result: '%s'\n", buf);
 180         }
 181 }
 182
 183 static int __init test_hexdump_init(void)
 184 {
 185         unsigned int i;
 186         int rowsize;
 187
 188         pr_info("Running tests...\n");
 189
 190         rowsize = (get_random_int() % 2 + 1) * 16;
 191         for (i = 0; i < 16; i++)
 192                 test_hexdump_set(rowsize, false);
 193
 194         rowsize = (get_random_int() % 2 + 1) * 16;
 195         for (i = 0; i < 16; i++)
 196                 test_hexdump_set(rowsize, true);
 197
 198         for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++)
 199                 test_hexdump_overflow(i, false);
 200
 201         for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++)
 202                 test_hexdump_overflow(i, true);
 203
 204         return -EINVAL;
 205 }
 206 module_init(test_hexdump_init);
 207 MODULE_LICENSE("Dual BSD/GPL");