[gsupplicant] Make sure that BSS SSID string is a valid UTF-8

include/gsupplicant_util.h

@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2017 Jolla Ltd.
+ * Contact: Slava Monich <slava.monich@jolla.com>
+ *
+ * You may use this file under the terms of BSD license as follows:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *   3. Neither the name of Jolla Ltd nor the names of its contributors may
+ *      be used to endorse or promote products derived from this software
+ *      without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef GSUPPLICANT_UTIL_H
+#define GSUPPLICANT_UTIL_H
+
+#include <gsupplicant_types.h>
+
+G_BEGIN_DECLS
+
+char*
+gsupplicant_utf8_from_bytes(
+    GBytes* bytes);
+
+G_END_DECLS
+
+#endif /* GSUPPLICANT_UTIL_H */
+
+/*
+ * Local Variables:
+ * mode: C
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */

src/gsupplicant_bss.c

@@ -433,11 +433,7 @@ gsupplicant_bss_update_ssid(
         }
         g_free(priv->ssid_str);
         if (ssid) {
-            gsize size = 0;
-            const void* data = g_bytes_get_data(ssid, &size);
-            priv->ssid_str = g_malloc(size + 1);
-            memcpy(priv->ssid_str, data, size);
-            priv->ssid_str[size] = 0;
+            priv->ssid_str = gsupplicant_utf8_from_bytes(ssid);
             GDEBUG("[%s] " PROXY_PROPERTY_NAME_SSID ": %s \"%s\"",
                 self->path, gsupplicant_format_bytes(ssid, FALSE),
                 priv->ssid_str);

src/gsupplicant_util.c

@@ -439,6 +439,36 @@ gsupplicant_variant_data_as_bytes(
     return NULL;
 }
 
+char*
+gsupplicant_utf8_from_bytes(
+    GBytes* bytes)
+{
+    if (bytes) {
+        gsize size = 0;
+        const char* ptr = g_bytes_get_data(bytes, &size);
+        if (size) {
+            GString* buf = g_string_sized_new(size);
+            while (size) {
+                const gchar* invalid = NULL;
+		if (g_utf8_validate(ptr, size, &invalid)) {
+                    g_string_append_len(buf, ptr, size);
+                    break;
+		} else {
+                    gsize valid = invalid - ptr;
+                    /* U+FFFD is REPLACEMENT CHARACTER */
+                    g_string_append_len(buf, ptr, valid);
+                    g_string_append(buf, "\357\277\275");
+                    ptr = invalid + 1;
+                    size -= valid + 1;
+                }
+            }
+            return g_string_free(buf, FALSE);
+        }
+        return g_strdup("");
+    }
+    return NULL;
+}
+
 /*
  * Local Variables:
  * mode: C

src/gsupplicant_util_p.h

@@ -33,7 +33,7 @@
 #ifndef GSUPPLICANT_UTIL_PRIVATE_H
 #define GSUPPLICANT_UTIL_PRIVATE_H
 
-#include <gsupplicant_types.h>
+#include <gsupplicant_util.h>
 
 typedef struct gsupplicant_name_int_pair {
     const char* name;

test/test_util/test_util.c

@@ -37,6 +37,8 @@
 #include <gutil_log.h>
 #include <glib/gstdio.h>
 
+#define TEST_PREFIX "/util/"
+
 #define BIT_FOO     0x01
 #define BIT_BAR     0x02
 #define BIT_EMPTY   0x04
@@ -435,13 +437,95 @@ test_util_dict_parse(
 }
 
 /*==========================================================================*
- * Common
+ * utf8_from_bytes
  *==========================================================================*/
 
-#define TEST_PREFIX "/util/"
+typedef struct test_util_utf8_data {
+    const char* name;
+    const void* in;
+    gsize in_size;
+    const guint32* ucs4;
+    glong ucs4_len;
+} TestUTF8Data;
+
+static const guint8 test_util_utf8_data_1_in[] = {
+    0xd1, 0x82, 0xd0, 0xb5, 0xd1, 0x81, 0xd1, 0x82
+};
+static const guint32 test_util_utf8_data_1_ucs4[] = {
+    0x0442, 0x0435, 0x0441, 0x0442
+};
+static const guint8 test_util_utf8_data_2_in[] = {
+    0xd1, 0x82, 0xd0, 0xb5, 0xd1, 0x81, 0xd1, 0x82, 0x81
+};
+static const guint32 test_util_utf8_data_2_ucs4[] = {
+    0x0442, 0x0435, 0x0441, 0x0442, 0xfffd
+};
+static const guint8 test_util_utf8_data_3_in[] = {
+    0xf0, 0xd1, 0x82, 0xd0, 0xb5, 0xd1, 0x81, 0xd1, 0x82
+};
+static const guint32 test_util_utf8_data_3_ucs4[] = {
+    0xfffd, 0x0442, 0x0435, 0x0441, 0x0442
+};
+static const TestUTF8Data test_util_utf8_data[] = {
+    {
+        TEST_PREFIX "utf8_from_bytes1",
+        test_util_utf8_data_1_in, G_N_ELEMENTS(test_util_utf8_data_1_in),
+        test_util_utf8_data_1_ucs4, G_N_ELEMENTS(test_util_utf8_data_1_ucs4)
+    },{
+        TEST_PREFIX "utf8_from_bytes2",
+        test_util_utf8_data_2_in, G_N_ELEMENTS(test_util_utf8_data_2_in),
+        test_util_utf8_data_2_ucs4, G_N_ELEMENTS(test_util_utf8_data_2_ucs4)
+    },{
+        TEST_PREFIX "utf8_from_bytes3",
+        test_util_utf8_data_3_in, G_N_ELEMENTS(test_util_utf8_data_3_in),
+        test_util_utf8_data_3_ucs4, G_N_ELEMENTS(test_util_utf8_data_3_ucs4)
+    }
+};
+
+static
+void
+test_util_utf8_from_bytes(
+    void)
+{
+    GBytes* nothing = g_bytes_new_static(NULL, 0);
+    char* empty = gsupplicant_utf8_from_bytes(nothing);
+    g_assert(!g_strcmp0(empty, ""));
+    g_assert(!gsupplicant_utf8_from_bytes(NULL));
+    g_bytes_unref(nothing);
+    g_free(empty);
+}
+
+static
+void
+test_util_utf8_from_bytes1(
+    gconstpointer data)
+{
+    const TestUTF8Data* test = data;
+    GBytes* bytes = g_bytes_new_static(test->in, test->in_size);
+    char* utf8 = gsupplicant_utf8_from_bytes(bytes);
+    if (utf8) {
+        GError* error = NULL;
+        glong len = 0;
+        gunichar* ucs4 = g_utf8_to_ucs4(utf8, -1, NULL, &len, &error);
+        g_assert(!error);
+        g_assert(test->ucs4);
+        g_assert(test->ucs4_len == len);
+        g_assert(!memcmp(ucs4, test->ucs4, sizeof(guint32)*len));
+        g_free(utf8);
+        g_free(ucs4);
+    } else {
+        g_assert(!test->ucs4);
+    }
+    g_bytes_unref(bytes);
+}
+
+/*==========================================================================*
+ * Common
+ *==========================================================================*/
 
 int main(int argc, char* argv[])
 {
+    int i;
     G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
     g_type_init();
     G_GNUC_END_IGNORE_DEPRECATIONS;
@@ -453,6 +537,11 @@ int main(int argc, char* argv[])
     g_test_add_func(TEST_PREFIX "cancel_later", test_util_cancel_later);
     g_test_add_func(TEST_PREFIX "abs_path", test_util_abs_path);
     g_test_add_func(TEST_PREFIX "dict_parse", test_util_dict_parse);
+    g_test_add_func(TEST_PREFIX "utf8_from_bytes", test_util_utf8_from_bytes);
+    for (i = 0; i < G_N_ELEMENTS(test_util_utf8_data); i++) {
+        const TestUTF8Data* test = test_util_utf8_data + i;
+        g_test_add_data_func(test->name, test, test_util_utf8_from_bytes1);
+    }
     test_init(&test_opt, argc, argv);
     return g_test_run();
 }