conf.c: require the index compare callback in TXT_DB lookups

src/conf.c

@@ -261,38 +261,42 @@ int wolfSSL_TXT_DB_create_index(WOLFSSL_TXT_DB *db, int field,
 {
     WOLFSSL_ENTER("wolfSSL_TXT_DB_create_index");
     (void)qual;
-    (void)cmp;
 
     if (!db || !hash || !cmp || field >= db->num_fields || field < 0) {
         WOLFSSL_MSG("Bad parameter");
         return WOLFSSL_FAILURE;
     }
 
     db->hash_fn[field] = hash;
+    db->cmp_fn[field] = cmp;
 
     return WOLFSSL_SUCCESS;
 }
 
 WOLFSSL_STRING *wolfSSL_TXT_DB_get_by_index(WOLFSSL_TXT_DB *db, int idx,
         WOLFSSL_STRING *value)
 {
+    WOLF_STACK_OF(WOLFSSL_STRING)* data;
+    WOLFSSL_STRING* row = NULL;
+    unsigned long hash;
+
     WOLFSSL_ENTER("wolfSSL_TXT_DB_get_by_index");
 
-    if (!db || !db->data || idx < 0 || idx >= db->num_fields) {
+    if (!db || !db->data || !value || idx < 0 || idx >= db->num_fields) {
         WOLFSSL_MSG("Bad parameter");
         return NULL;
     }
 
-    if (!db->hash_fn[idx]) {
-        WOLFSSL_MSG("Missing hash functions");
+    if (!db->hash_fn[idx] || !db->cmp_fn[idx]) {
+        WOLFSSL_MSG("Missing hash or compare functions");
         return NULL;
     }
 
     /* If first data struct has correct hash function
      * then assume others do too */
     if (db->data->hash_fn != db->hash_fn[idx]) {
         /* Set the hash and comp functions */
-        WOLF_STACK_OF(WOLFSSL_STRING)* data = db->data;
+        data = db->data;
         while (data) {
             if (data->hash_fn != db->hash_fn[idx]) {
                 data->hash_fn = db->hash_fn[idx];
@@ -301,7 +305,22 @@ WOLFSSL_STRING *wolfSSL_TXT_DB_get_by_index(WOLFSSL_TXT_DB *db, int idx,
             data= data->next;
         }
     }
-    return (WOLFSSL_STRING*) wolfSSL_lh_retrieve(db->data, value);
+
+    hash = db->hash_fn[idx](value);
+    for (data = db->data; data != NULL; data = data->next) {
+        row = (WOLFSSL_STRING*)wolfssl_sk_node_get_data(data, 0);
+        if (row != NULL) {
+            if (data->hash == 0) {
+                data->hash = db->hash_fn[idx](row);
+            }
+            if ((data->hash == hash) && (db->cmp_fn[idx](row, value) == 0)) {
+                break;
+            }
+        }
+        row = NULL;
+    }
+
+    return row;
 }
 
 #endif /* OPENSSL_ALL && !NO_BIO */

tests/api.c

@@ -26658,6 +26658,13 @@ static int TXT_DB_cmp(const WOLFSSL_STRING *a, const WOLFSSL_STRING *b)
 {
     return XSTRCMP(a[3], b[3]);
 }
+
+/* Every row collides, so only TXT_DB_cmp can tell rows apart */
+static word32 TXT_DB_hash_const(const WOLFSSL_STRING *s)
+{
+    (void)s;
+    return 1;
+}
 #endif
 
 static int test_wolfSSL_TXT_DB(void)
@@ -26666,6 +26673,7 @@ static int test_wolfSSL_TXT_DB(void)
 #if !defined(NO_FILESYSTEM) && !defined(NO_BIO)
     BIO *bio = NULL;
     TXT_DB *db = NULL;
+    WOLFSSL_STRING *row = NULL;
     const int columns = 6;
     const char *fields[6] = {
         "V",
@@ -26710,6 +26718,18 @@ static int test_wolfSSL_TXT_DB(void)
     fields[3] = "";
     ExpectNull(TXT_DB_get_by_index(db, 3, (WOLFSSL_STRING*)fields));
 
+    /* Colliding hashes: the row returned must be the one cmp matches */
+    ExpectIntEQ(TXT_DB_create_index(db, 3, NULL,
+        (wolf_sk_hash_cb)(wc_ptr_t)TXT_DB_hash_const,
+        (wolf_lh_compare_cb)TXT_DB_cmp), 1);
+    fields[3] = "12DA";
+    ExpectNotNull(row = TXT_DB_get_by_index(db, 3, (WOLFSSL_STRING*)fields));
+    if (row != NULL) {
+        ExpectStrEQ(row[3], "12DA");
+    }
+    fields[3] = "FFFF";
+    ExpectNull(TXT_DB_get_by_index(db, 3, (WOLFSSL_STRING*)fields));
+
     TXT_DB_free(db);
 #endif
     return EXPECT_RESULT();

wolfssl/openssl/txt_db.h

@@ -26,18 +26,20 @@
 
 #define WOLFSSL_TXT_DB_MAX_FIELDS 10
 
+typedef int (*wolf_lh_compare_cb)(const void* a,
+                                  const void* b);
+
 struct WOLFSSL_TXT_DB {
     int num_fields;
     WOLF_STACK_OF(WOLFSSL_STRING) *data;
     long error;
     long arg1;
     long arg2;
     wolf_sk_hash_cb hash_fn[WOLFSSL_TXT_DB_MAX_FIELDS];
+    wolf_lh_compare_cb cmp_fn[WOLFSSL_TXT_DB_MAX_FIELDS];
 };
 
 typedef struct WOLFSSL_TXT_DB WOLFSSL_TXT_DB;
-typedef int (*wolf_lh_compare_cb)(const void* a,
-                                  const void* b);
 
 WOLFSSL_API WOLFSSL_TXT_DB *wolfSSL_TXT_DB_read(WOLFSSL_BIO *in, int num);
 WOLFSSL_API long wolfSSL_TXT_DB_write(WOLFSSL_BIO  *out, WOLFSSL_TXT_DB *db);