1 /*
2 * Copyright 2016 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.handler.codec.http.multipart;
17
18 import io.netty.handler.codec.http.HttpConstants;
19 import io.netty.handler.codec.http.HttpHeaderValidationUtil;
20 import io.netty.util.internal.ObjectUtil;
21
22 final class FileUploadUtil {
23
24 private FileUploadUtil() { }
25
26 static int hashCode(FileUpload upload) {
27 return upload.getName().hashCode();
28 }
29
30 static boolean equals(FileUpload upload1, FileUpload upload2) {
31 return upload1.getName().equalsIgnoreCase(upload2.getName());
32 }
33
34 static int compareTo(FileUpload upload1, FileUpload upload2) {
35 return upload1.getName().compareToIgnoreCase(upload2.getName());
36 }
37
38 /**
39 * Control characters, the DEL character, double-quote, and backslash are either disallowed or strongly discouraged,
40 * depending on which {@code multipart/form-data} specification you read.
41 * This method conservatively rejects all of them, and is used for <em>outbound</em> (encoding) filenames.
42 * @param filename The filename to check.
43 * @return The validated filename, unchanged.
44 */
45 static String validateFileNameForMultiPart(String filename) {
46 int length = ObjectUtil.checkNotNull(filename, "filename").length();
47 for (int i = 0; i < length; i++) {
48 char c = filename.charAt(i);
49 if (c < HttpConstants.SP /*control character block*/ || c == HttpConstants.DEL ||
50 c == HttpConstants.DOUBLE_QUOTE || c == HttpConstants.BACKSLASH) {
51 throw new IllegalArgumentException(
52 String.format("Illegal filename character 0x%02x at index %d", (int) c, i));
53 }
54 }
55 return filename;
56 }
57
58 /**
59 * Control characters and the DEL character are either disallowed or strongly discouraged in the
60 * {@code Content-Type}.
61 * Space and tab is allowed except for the first character, quotation and other special characters are allowed.
62 * <p>
63 * The Content-Type value MUST be structured in the form of {@code type/subtype parameters}.
64 * See <a href="https://www.rfc-editor.org/rfc/rfc9110.html#section-8.3.1">RFC 9110 §8.3.1</a>,
65 * and <a href="https://www.rfc-editor.org/info/rfc2045/#section-5.1">RFC 2045 §5.1</a>.
66 * <p>
67 * This is used for multipart <em>encoding</em>, so we refuse to emit a malformed content type.
68 *
69 * @param contentType The Content-Type header value to check.
70 * @return The valid Content-Type header value, unchanged.
71 */
72 static String validateContentTypeForMultiPart(String contentType) {
73 checkContentTypeForMultiPart(
74 ObjectUtil.checkNotNull(contentType, "contentType"), true);
75 return contentType;
76 }
77
78 /**
79 * Determine if the given content type value is syntactically valid and well-formed.
80 * <p>
81 * The Content-Type value is valid if it is structured in the form of {@code type/subtype parameters}.
82 * See <a href="https://www.rfc-editor.org/rfc/rfc9110.html#section-8.3.1">RFC 9110 §8.3.1</a>,
83 * and <a href="https://www.rfc-editor.org/info/rfc2045/#section-5.1">RFC 2045 §5.1</a>.
84 * <p>
85 * This is used for multipart <em>decoding</em>, where
86 * <a href="https://www.rfc-editor.org/info/rfc2045/#section-5.2">RFC 2045 §5.2</a>
87 * recommends that syntactically invalid content type values be replaced with a default.
88 *
89 * @param contentType The Content-Type header value to check.
90 * @return {@code true} if the Content-Type header value is valid, otherwise {@code false}.
91 */
92 static boolean isContentTypeForMultiPartValid(String contentType) {
93 return contentType != null && checkContentTypeForMultiPart(contentType, false);
94 }
95
96 private static boolean checkContentTypeForMultiPart(String contentType, boolean throwIfInvalid) {
97 int index = HttpHeaderValidationUtil.validateValidHeaderValue(contentType);
98 if (index != -1) {
99 if (throwIfInvalid) {
100 throw new IllegalArgumentException(
101 String.format("Illegal Content-Type character 0x%02x at index %d",
102 (int) contentType.charAt(index), index));
103 }
104 return false;
105 }
106
107 int slash = contentType.indexOf('/');
108 int semicolon = contentType.indexOf(';');
109 if (slash == -1 ||
110 slash == 0 ||
111 (semicolon == -1 && slash == contentType.length() - 1) ||
112 (semicolon != -1 && slash + 1 >= semicolon)) {
113 if (throwIfInvalid) {
114 throw new IllegalArgumentException("Malformed content type value: " +
115 "index of '/' is " + slash + " content type length " + contentType.length());
116 }
117 return false;
118 }
119 return true;
120 }
121 }