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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.net.ftp.parser;
19  
20  import java.text.ParsePosition;
21  import java.text.SimpleDateFormat;
22  import java.time.Instant;
23  import java.util.Calendar;
24  import java.util.Date;
25  import java.util.GregorianCalendar;
26  import java.util.HashMap;
27  import java.util.Locale;
28  import java.util.TimeZone;
29  
30  import org.apache.commons.net.ftp.FTPFile;
31  import org.apache.commons.net.ftp.FTPFileEntryParserImpl;
32  
33  /**
34   * Parser class for MSLT and MLSD replies. See RFC 3659.
35   * <p>
36   * Format is as follows:
37   * </p>
38   *
39   * <pre>
40   * entry            = [ facts ] SP pathname
41   * facts            = 1*( fact ";" )
42   * fact             = factname "=" value
43   * factname         = "Size" / "Modify" / "Create" /
44   *                    "Type" / "Unique" / "Perm" /
45   *                    "Lang" / "Media-Type" / "CharSet" /
46   * os-depend-fact / local-fact
47   * os-depend-fact   = {IANA assigned OS name} "." token
48   * local-fact       = "X." token
49   * value            = *SCHAR
50   *
51   * Sample os-depend-fact:
52   * UNIX.group=0;UNIX.mode=0755;UNIX.owner=0;
53   * </pre>
54   * <p>
55   * A single control response entry (MLST) is returned with a leading space; multiple (data) entries are returned without any leading spaces. The parser requires
56   * that the leading space from the MLST entry is removed. MLSD entries can begin with a single space if there are no facts.
57   * </p>
58   *
59   * @since 3.0
60   */
61  public class MLSxEntryParser extends FTPFileEntryParserImpl {
62      // This class is immutable, so a single instance can be shared.
63      private static final MLSxEntryParser INSTANCE = new MLSxEntryParser();
64  
65      private static final HashMap<String, Integer> TYPE_TO_INT = new HashMap<>();
66      static {
67          TYPE_TO_INT.put("file", Integer.valueOf(FTPFile.FILE_TYPE));
68          TYPE_TO_INT.put("cdir", Integer.valueOf(FTPFile.DIRECTORY_TYPE)); // listed directory
69          TYPE_TO_INT.put("pdir", Integer.valueOf(FTPFile.DIRECTORY_TYPE)); // a parent dir
70          TYPE_TO_INT.put("dir", Integer.valueOf(FTPFile.DIRECTORY_TYPE)); // dir or sub-dir
71      }
72  
73      private static final int[] UNIX_GROUPS = { // Groups in order of mode digits
74              FTPFile.USER_ACCESS, FTPFile.GROUP_ACCESS, FTPFile.WORLD_ACCESS, };
75  
76      private static final int[][] UNIX_PERMS = { // perm bits, broken down by octal int value
77              /* 0 */ {}, /* 1 */ { FTPFile.EXECUTE_PERMISSION }, /* 2 */ { FTPFile.WRITE_PERMISSION },
78              /* 3 */ { FTPFile.EXECUTE_PERMISSION, FTPFile.WRITE_PERMISSION }, /* 4 */ { FTPFile.READ_PERMISSION },
79              /* 5 */ { FTPFile.READ_PERMISSION, FTPFile.EXECUTE_PERMISSION }, /* 6 */ { FTPFile.READ_PERMISSION, FTPFile.WRITE_PERMISSION },
80              /* 7 */ { FTPFile.READ_PERMISSION, FTPFile.WRITE_PERMISSION, FTPFile.EXECUTE_PERMISSION }, };
81  
82      public static MLSxEntryParser getInstance() {
83          return INSTANCE;
84      }
85  
86      public static FTPFile parseEntry(final String entry) {
87          return INSTANCE.parseFTPEntry(entry);
88      }
89  
90      /**
91       * Parse a GMT time stamp of the form yyyyMMDDHHMMSS[.sss]
92       *
93       * @param timestamp the date-time to parse
94       * @return a Calendar entry, may be {@code null}
95       * @since 3.4
96       */
97      public static Calendar parseGMTdateTime(final String timestamp) {
98          final SimpleDateFormat dateFormat;
99          final boolean hasMillis;
100         if (timestamp.contains(".")) {
101             dateFormat = new SimpleDateFormat("yyyyMMddHHmmss.SSS");
102             hasMillis = true;
103         } else {
104             dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
105             hasMillis = false;
106         }
107         final TimeZone gmtTimeZone = TimeZone.getTimeZone("GMT");
108         // both time zones need to be set for the parse to work OK
109         dateFormat.setTimeZone(gmtTimeZone);
110         final GregorianCalendar gCalendar = new GregorianCalendar(gmtTimeZone);
111         final ParsePosition pos = new ParsePosition(0);
112         dateFormat.setLenient(false); // We want to parse the whole string
113         final Date parsed = dateFormat.parse(timestamp, pos);
114         if (pos.getIndex() != timestamp.length()) {
115             return null; // did not fully parse the input
116         }
117         gCalendar.setTime(parsed);
118         if (!hasMillis) {
119             gCalendar.clear(Calendar.MILLISECOND); // flag up missing ms units
120         }
121         return gCalendar;
122     }
123 
124     /**
125      * Parse a GMT time stamp of the form yyyyMMDDHHMMSS[.sss]
126      *
127      * @param timestamp the date-time to parse
128      * @return a Calendar entry, may be {@code null}
129      * @since 3.9.0
130      */
131     public static Instant parseGmtInstant(final String timestamp) {
132         return parseGMTdateTime(timestamp).toInstant();
133     }
134 
135     /**
136      * Create the parser for MSLT and MSLD listing entries This class is immutable, so one can use {@link #getInstance()} instead.
137      */
138     public MLSxEntryParser() {
139     }
140 
141     // perm-fact = "Perm" "=" *pvals
142     // pvals = "a" / "c" / "d" / "e" / "f" /
143     // "l" / "m" / "p" / "r" / "w"
144     private void doUnixPerms(final FTPFile file, final String valueLowerCase) {
145         for (final char c : valueLowerCase.toCharArray()) {
146             // TODO these are mostly just guesses at present
147             switch (c) {
148             case 'a': // (file) may APPEnd
149                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
150                 break;
151             case 'c': // (dir) files may be created in the dir
152                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
153                 break;
154             case 'd': // deletable
155                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
156                 break;
157             case 'e': // (dir) can change to this dir
158                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.READ_PERMISSION, true);
159                 break;
160             case 'f': // (file) renamable
161                 // ?? file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
162                 break;
163             case 'l': // (dir) can be listed
164                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.EXECUTE_PERMISSION, true);
165                 break;
166             case 'm': // (dir) can create directory here
167                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
168                 break;
169             case 'p': // (dir) entries may be deleted
170                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
171                 break;
172             case 'r': // (files) file may be RETRieved
173                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.READ_PERMISSION, true);
174                 break;
175             case 'w': // (files) file may be STORed
176                 file.setPermission(FTPFile.USER_ACCESS, FTPFile.WRITE_PERMISSION, true);
177                 break;
178             default:
179                 break;
180             // ignore unexpected flag for now.
181             } // switch
182         } // each char
183     }
184 
185     @Override
186     public FTPFile parseFTPEntry(final String entry) {
187         if (entry.startsWith(" ")) { // leading space means no facts are present
188             if (entry.length() > 1) { // is there a path name?
189                 final FTPFile file = new FTPFile();
190                 file.setRawListing(entry);
191                 file.setName(entry.substring(1));
192                 return file;
193             }
194             return null; // Invalid - no pathname
195 
196         }
197         final String[] parts = entry.split(" ", 2); // Path may contain space
198         if (parts.length != 2 || parts[1].isEmpty()) {
199             return null; // no space found or no file name
200         }
201         final String factList = parts[0];
202         if (!factList.endsWith(";")) {
203             return null;
204         }
205         final FTPFile file = new FTPFile();
206         file.setRawListing(entry);
207         file.setName(parts[1]);
208         final String[] facts = factList.split(";");
209         final boolean hasUnixMode = parts[0].toLowerCase(Locale.ENGLISH).contains("unix.mode=");
210         for (final String fact : facts) {
211             final String[] factparts = fact.split("=", -1); // Don't drop empty values
212 // Sample missing permission
213 // drwx------   2 mirror   mirror       4096 Mar 13  2010 subversion
214 // modify=20100313224553;perm=;type=dir;unique=811U282598;UNIX.group=500;UNIX.mode=0700;UNIX.owner=500; subversion
215             if (factparts.length != 2) {
216                 return null; // invalid - there was no "=" sign
217             }
218             final String factname = factparts[0].toLowerCase(Locale.ENGLISH);
219             final String factvalue = factparts[1];
220             if (factvalue.isEmpty()) {
221                 continue; // nothing to see here
222             }
223             final String valueLowerCase = factvalue.toLowerCase(Locale.ENGLISH);
224             if ("size".equals(factname) || "sizd".equals(factname)) {
225                 file.setSize(Long.parseLong(factvalue));
226             } else if ("modify".equals(factname)) {
227                 final Calendar parsed = parseGMTdateTime(factvalue);
228                 if (parsed == null) {
229                     return null;
230                 }
231                 file.setTimestamp(parsed);
232             } else if ("type".equals(factname)) {
233                 final Integer intType = TYPE_TO_INT.get(valueLowerCase);
234                 if (intType == null) {
235                     file.setType(FTPFile.UNKNOWN_TYPE);
236                 } else {
237                     file.setType(intType.intValue());
238                 }
239             } else if (factname.startsWith("unix.")) {
240                 final String unixfact = factname.substring("unix.".length()).toLowerCase(Locale.ENGLISH);
241                 if ("group".equals(unixfact)) {
242                     file.setGroup(factvalue);
243                 } else if ("owner".equals(unixfact)) {
244                     file.setUser(factvalue);
245                 } else if ("mode".equals(unixfact)) { // e.g. 0[1]755
246                     final int off = factvalue.length() - 3; // only parse last 3 digits
247                     for (int i = 0; i < 3; i++) {
248                         final int ch = factvalue.charAt(off + i) - '0';
249                         if (ch >= 0 && ch <= 7) { // Check it's valid octal
250                             for (final int p : UNIX_PERMS[ch]) {
251                                 file.setPermission(UNIX_GROUPS[i], p, true);
252                             }
253                         } else {
254                             // TODO should this cause failure, or can it be reported somehow?
255                         }
256                     } // digits
257                 } // mode
258             } // unix.
259             else if (!hasUnixMode && "perm".equals(factname)) { // skip if we have the UNIX.mode
260                 doUnixPerms(file, valueLowerCase);
261             } // process "perm"
262         } // each fact
263         return file;
264     }
265 }