Fix case insensitive matching in isc_ht hash table implementation

The case insensitive matching in isc_ht was basically completely broken
as only the hashvalue computation was case insensitive, but the key
comparison was always case sensitive.

(cherry picked from commit c462d65b2fd0db362947db4a18a87df78f8d8e5d)

diff --git a/lib/isc/ht.c b/lib/isc/ht.c
index 807efe16874960ba0d007392876f9f00bea1d276..19f0b2c0b952f093c8885bab65b97795d9401201 100644 (file)
--- a/lib/isc/ht.c
+++ b/lib/isc/ht.c
@@ -94,11 +94,54 @@ maybe_rehash(isc_ht_t *ht, size_t newcount);
 static isc_result_t
 isc__ht_iter_next(isc_ht_iter_t *it);
 
+static uint8_t maptolower[] = {
+       0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+       0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+       0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
+       0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+       0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+       0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
+       0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73,
+       0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
+       0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b,
+       0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
+       0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83,
+       0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+       0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
+       0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
+       0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb3,
+       0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
+       0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb,
+       0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
+       0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3,
+       0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
+       0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb,
+       0xfc, 0xfd, 0xfe, 0xff
+};
+
+static int
+memcasecmp(const void *vs1, const void *vs2, size_t len) {
+       uint8_t const *s1 = vs1;
+       uint8_t const *s2 = vs2;
+       for (size_t i = 0; i < len; i++) {
+               uint8_t u1 = s1[i];
+               uint8_t u2 = s2[i];
+               int U1 = maptolower[u1];
+               int U2 = maptolower[u2];
+               int diff = U1 - U2;
+               if (diff) {
+                       return diff;
+               }
+       }
+       return 0;
+}
+
 static bool
 isc__ht_node_match(isc_ht_node_t *node, const uint32_t hashval,
-                  const uint8_t *key, uint32_t keysize) {
+                  const uint8_t *key, uint32_t keysize, bool case_sensitive) {
        return (node->hashval == hashval && node->keysize == keysize &&
-               memcmp(node->key, key, keysize) == 0);
+               (case_sensitive ? (memcmp(node->key, key, keysize) == 0)
+                               : (memcasecmp(node->key, key, keysize) == 0)));
 }
 
 static uint32_t
@@ -345,7 +388,9 @@ nexttable:
        for (isc_ht_node_t *node = ht->table[findex][hash]; node != NULL;
             node = node->next)
        {
-               if (isc__ht_node_match(node, hashval, key, keysize)) {
+               if (isc__ht_node_match(node, hashval, key, keysize,
+                                      ht->case_sensitive))
+               {
                        return (node);
                }
        }
@@ -394,7 +439,9 @@ isc__ht_delete(isc_ht_t *ht, const unsigned char *key, const uint32_t keysize,
        for (isc_ht_node_t *node = ht->table[idx][hash]; node != NULL;
             prev = node, node = node->next)
        {
-               if (isc__ht_node_match(node, hashval, key, keysize)) {
+               if (isc__ht_node_match(node, hashval, key, keysize,
+                                      ht->case_sensitive))
+               {
                        if (prev == NULL) {
                                ht->table[idx][hash] = node->next;
                        } else {

diff --git a/lib/isc/tests/ht_test.c b/lib/isc/tests/ht_test.c
index 2fe93602bd52d9553a55e97cc097006354a027c5..144d8596397c0adc6f985443ecbdee56a95a5dca 100644 (file)
--- a/lib/isc/tests/ht_test.c
+++ b/lib/isc/tests/ht_test.c
@@ -345,9 +345,69 @@ isc_ht_iterator_test(void **state) {
        test_ht_iterator();
 }
 
+static void
+isc_ht_case(void **state) {
+       UNUSED(state);
+
+       isc_ht_t *ht = NULL;
+       void *f = NULL;
+       isc_result_t result = ISC_R_UNSET;
+       isc_mem_t *mctx = NULL;
+
+       result = isc_mem_createx2(0, 0, default_memalloc, default_memfree,
+                                 NULL, &mctx, 0);
+       assert_int_equal(result, ISC_R_SUCCESS);
+
+       unsigned char lower[16] = { "test case" };
+       unsigned char same[16] = { "test case" };
+       unsigned char upper[16] = { "TEST CASE" };
+       unsigned char mixed[16] = { "tEsT CaSe" };
+
+       isc_ht_init(&ht, mctx, 8, ISC_HT_CASE_SENSITIVE);
+       assert_non_null(ht);
+
+       result = isc_ht_add(ht, lower, 16, (void *)lower);
+       assert_int_equal(result, ISC_R_SUCCESS);
+
+       result = isc_ht_add(ht, same, 16, (void *)same);
+       assert_int_equal(result, ISC_R_EXISTS);
+
+       result = isc_ht_add(ht, upper, 16, (void *)upper);
+       assert_int_equal(result, ISC_R_SUCCESS);
+
+       result = isc_ht_find(ht, mixed, 16, &f);
+       assert_int_equal(result, ISC_R_NOTFOUND);
+       assert_null(f);
+
+       isc_ht_destroy(&ht);
+       assert_null(ht);
+
+       isc_ht_init(&ht, mctx, 8, ISC_HT_CASE_INSENSITIVE);
+       assert_non_null(ht);
+
+       result = isc_ht_add(ht, lower, 16, (void *)lower);
+       assert_int_equal(result, ISC_R_SUCCESS);
+
+       result = isc_ht_add(ht, same, 16, (void *)same);
+       assert_int_equal(result, ISC_R_EXISTS);
+
+       result = isc_ht_add(ht, upper, 16, (void *)upper);
+       assert_int_equal(result, ISC_R_EXISTS);
+
+       result = isc_ht_find(ht, mixed, 16, &f);
+       assert_int_equal(result, ISC_R_SUCCESS);
+       assert_ptr_equal(f, &lower);
+
+       isc_ht_destroy(&ht);
+       assert_null(ht);
+
+       isc_mem_detach(&mctx);
+}
+
 int
 main(void) {
        const struct CMUnitTest tests[] = {
+               cmocka_unit_test(isc_ht_case),
                cmocka_unit_test(isc_ht_20),
                cmocka_unit_test(isc_ht_8),
                cmocka_unit_test(isc_ht_1),