/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#include "common-ssh/sftp.h"

#include <CUnit/CUnit.h>
#include <stdlib.h>

/**
 * Test which verifies absolute Windows-style paths are correctly normalized to
 * absolute paths with UNIX separators and no relative components.
 */
void test_sftp__normalize_absolute_windows() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\bar\\baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\bar\\..\\baz\\"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\bar\\..\\..\\baz\\a\\..\\b"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz/b", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\.\\bar\\baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\bar\\..\\..\\..\\..\\..\\..\\baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz", sizeof(normalized));

}

/**
 * Test which verifies absolute UNIX-style paths are correctly normalized to
 * absolute paths with UNIX separators and no relative components.
 */
void test_sftp__normalize_absolute_unix() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo/bar/baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo/bar/../baz/"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo/bar/../../baz/a/../b"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz/b", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo/./bar/baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo/bar/../../../../../../baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz", sizeof(normalized));

}

/**
 * Test which verifies absolute paths consisting of mixed Windows and UNIX path
 * separators are correctly normalized to absolute paths with UNIX separators
 * and no relative components.
 */
void test_sftp__normalize_absolute_mixed() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo/bar\\baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "/foo\\bar/..\\baz/"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo/bar\\../../baz\\a\\..\\b"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz/b", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo\\.\\bar/baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/foo/bar/baz", sizeof(normalized));

    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "\\foo/bar\\../..\\..\\..\\../..\\baz"), 0);
    CU_ASSERT_NSTRING_EQUAL(normalized, "/baz", sizeof(normalized));

}

/**
 * Test which verifies relative Windows-style paths are always rejected.
 */
void test_sftp__normalize_relative_windows() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ""), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "."), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ".."), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ".\\foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "..\\foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "foo\\bar\\baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ".\\foo\\bar\\baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "..\\foo\\bar\\baz"), 0);

}

/**
 * Test which verifies relative UNIX-style paths are always rejected.
 */
void test_sftp__normalize_relative_unix() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ""), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "."), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ".."), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "./foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "../foo"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "foo/bar/baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "./foo/bar/baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "../foo/bar/baz"), 0);

}

/**
 * Test which verifies relative paths consisting of mixed Windows and UNIX path
 * separators are always rejected.
 */
void test_sftp__normalize_relative_mixed() {

    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "foo\\bar/baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, ".\\foo/bar/baz"), 0);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, "../foo\\bar\\baz"), 0);

}

/**
 * Generates a dynamically-allocated path having the given number of bytes, not
 * counting the null-terminator. The path will contain only UNIX-style path
 * separators. The returned path must eventually be freed with a call to
 * free().
 *
 * @param length
 *     The number of bytes to include in the generated path, not counting the
 *     null-terminator. If -1, the length of the path will be automatically
 *     determined from the provided max_depth.
 *
 * @param max_depth
 *     The maximum number of path components to include within the generated
 *     path.
 *
 * @return
 *     A dynamically-allocated path containing the given number of bytes, not
 *     counting the null-terminator. This path must eventually be freed with a
 *     call to free().
 */
static char* generate_path(int length, int max_depth) {

    /* If no length given, calculate space required from max_depth */
    if (length == -1)
        length = max_depth * 2;

    int i;
    char* input = malloc(length + 1);

    /* Fill path with /x/x/x/x/x/x/x/x/x/x/.../xxxxxxxxx... */
    for (i = 0; i < length; i++) {
        if (max_depth > 0 && i % 2 == 0) {
            input[i] = '/';
            max_depth--;
        }
        else
            input[i] = 'x';
    }

    /* Add null terminator */
    input[length] = '\0';

    return input;

}

/**
 * Test which verifies that paths exceeding the maximum path length are
 * rejected.
 */
void test_sftp__normalize_long() {

    char* input;
    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    /* Exceeds maximum length by a factor of 2 */
    input = generate_path(GUAC_COMMON_SSH_SFTP_MAX_PATH * 2, GUAC_COMMON_SSH_SFTP_MAX_DEPTH);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

    /* Exceeds maximum length by one byte */
    input = generate_path(GUAC_COMMON_SSH_SFTP_MAX_PATH, GUAC_COMMON_SSH_SFTP_MAX_DEPTH);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

    /* Exactly maximum length */
    input = generate_path(GUAC_COMMON_SSH_SFTP_MAX_PATH - 1, GUAC_COMMON_SSH_SFTP_MAX_DEPTH);
    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

}

/**
 * Test which verifies that paths exceeding the maximum path depth are
 * rejected.
 */
void test_sftp__normalize_deep() {

    char* input;
    char normalized[GUAC_COMMON_SSH_SFTP_MAX_PATH];

    /* Exceeds maximum depth by a factor of 2 */
    input = generate_path(-1, GUAC_COMMON_SSH_SFTP_MAX_DEPTH * 2);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

    /* Exceeds maximum depth by one component */
    input = generate_path(-1, GUAC_COMMON_SSH_SFTP_MAX_DEPTH + 1);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

    /* Exactly maximum depth (should still be rejected as SFTP depth limits are
     * set such that a path with the maximum depth will exceed the maximum
     * length) */
    input = generate_path(-1, GUAC_COMMON_SSH_SFTP_MAX_DEPTH);
    CU_ASSERT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

    /* Less than maximum depth */
    input = generate_path(-1, GUAC_COMMON_SSH_SFTP_MAX_DEPTH - 1);
    CU_ASSERT_NOT_EQUAL(guac_common_ssh_sftp_normalize_path(normalized, input), 0);
    free(input);

}