1 /* Handle a .class file embedded in a .zip archive.
2    This extracts a member from a .zip file, but does not handle
3    uncompression (since that is not needed for classes.zip).
4    Copyright (C) 1996-2016 Free Software Foundation, Inc.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
11 any later version.
12 
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 GNU General Public License for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.
21 
22 Java and all Java-based marks are trademarks or registered trademarks
23 of Sun Microsystems, Inc. in the United States and other countries.
24 The Free Software Foundation is independent of Sun Microsystems, Inc.  */
25 
26 /* Written by Per Bothner <bothner@cygnus.com>, February 1996. */
27 
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "zipfile.h"
32 
33 /* This stuff is partly based on the 28 August 1994 public release of the
34 Info-ZIP group's portable UnZip zipfile-extraction program (and related
35 utilities). */
36 
37 /*************/
38 /*  Defines  */
39 /*************/
40 
41 #define UNZIP
42 #define UNZIP_VERSION     20   /* compatible with PKUNZIP 2.0 */
43 #define VMS_UNZIP_VERSION 42   /* if OS-needed-to-extract is VMS:  can do */
44 
45 
46 #define ZSUFX             ".zip"
47 #define CENTRAL_HDR_SIG   "\113\001\002"   /* the infamous "PK" signature */
48 #define LOCAL_HDR_SIG     "\113\003\004"   /*  bytes, sans "P" (so unzip */
49 #define END_CENTRAL_SIG   "\113\005\006"   /*  executable not mistaken for */
50 #define EXTD_LOCAL_SIG    "\113\007\010"   /*  zipfile itself) */
51 
52 #define STORED            0    /* compression methods */
53 #define SHRUNK            1
54 #define REDUCED1          2
55 #define REDUCED2          3
56 #define REDUCED3          4
57 #define REDUCED4          5
58 #define IMPLODED          6
59 #define TOKENIZED         7
60 #define DEFLATED          8
61 #define NUM_METHODS       9    /* index of last method + 1 */
62 /* don't forget to update list_files() appropriately if NUM_METHODS changes */
63 
64 #define PK_OK             0    /* no error */
65 #define PK_COOL           0    /* no error */
66 #define PK_GNARLY         0    /* no error */
67 #define PK_WARN           1    /* warning error */
68 #define PK_ERR            2    /* error in zipfile */
69 #define PK_BADERR         3    /* severe error in zipfile */
70 #define PK_MEM            4    /* insufficient memory */
71 #define PK_MEM2           5    /* insufficient memory */
72 #define PK_MEM3           6    /* insufficient memory */
73 #define PK_MEM4           7    /* insufficient memory */
74 #define PK_MEM5           8    /* insufficient memory */
75 #define PK_NOZIP          9    /* zipfile not found */
76 #define PK_PARAM          10   /* bad or illegal parameters specified */
77 #define PK_FIND           11   /* no files found */
78 #define PK_DISK           50   /* disk full */
79 #define PK_EOF            51   /* unexpected EOF */
80 
81 /*---------------------------------------------------------------------------
82     True sizes of the various headers, as defined by PKWARE--so it is not
83     likely that these will ever change.  But if they do, make sure both these
84     defines AND the typedefs below get updated accordingly.
85   ---------------------------------------------------------------------------*/
86 #define LREC_SIZE     26    /* lengths of local file headers, central */
87 #define CREC_SIZE     42    /*  directory headers, and the end-of-    */
88 #define ECREC_SIZE    18    /*  central-dir record, respectively      */
89 
90 
91 #ifndef SEEK_SET
92 #  define SEEK_SET  0
93 #  define SEEK_CUR  1
94 #  define SEEK_END  2
95 #endif
96 
97 /**************/
98 /*  Typedefs  */
99 /**************/
100 
101 typedef char              boolean;
102 typedef unsigned char     uch;  /* code assumes unsigned bytes; these type-  */
103 typedef unsigned short    ush;  /*  defs replace byte/UWORD/ULONG (which are */
104 typedef unsigned long     ulg;  /*  predefined on some systems) & match zip  */
105 
106 /*---------------------------------------------------------------------------
107     Zipfile layout declarations.  If these headers ever change, make sure the
108     xxREC_SIZE defines (above) change with them!
109   ---------------------------------------------------------------------------*/
110 
111    typedef uch   local_byte_hdr[ LREC_SIZE ];
112 #      define L_VERSION_NEEDED_TO_EXTRACT_0     0
113 #      define L_VERSION_NEEDED_TO_EXTRACT_1     1
114 #      define L_GENERAL_PURPOSE_BIT_FLAG        2
115 #      define L_COMPRESSION_METHOD              4
116 #      define L_LAST_MOD_FILE_TIME              6
117 #      define L_LAST_MOD_FILE_DATE              8
118 #      define L_CRC32                           10
119 #      define L_COMPRESSED_SIZE                 14
120 #      define L_UNCOMPRESSED_SIZE               18
121 #      define L_FILENAME_LENGTH                 22
122 #      define L_EXTRA_FIELD_LENGTH              24
123 
124   typedef uch   cdir_byte_hdr[ CREC_SIZE ];
125 #      define C_VERSION_MADE_BY_0               0
126 #      define C_VERSION_MADE_BY_1               1
127 #      define C_VERSION_NEEDED_TO_EXTRACT_0     2
128 #      define C_VERSION_NEEDED_TO_EXTRACT_1     3
129 #      define C_GENERAL_PURPOSE_BIT_FLAG        4
130 #      define C_COMPRESSION_METHOD              6
131 #      define C_LAST_MOD_FILE_TIME              8
132 #      define C_LAST_MOD_FILE_DATE              10
133 #      define C_CRC32                           12
134 #      define C_COMPRESSED_SIZE                 16
135 #      define C_UNCOMPRESSED_SIZE               20
136 #      define C_FILENAME_LENGTH                 24
137 #      define C_EXTRA_FIELD_LENGTH              26
138 #      define C_FILE_COMMENT_LENGTH             28
139 #      define C_DISK_NUMBER_START               30
140 #      define C_INTERNAL_FILE_ATTRIBUTES        32
141 #      define C_EXTERNAL_FILE_ATTRIBUTES        34
142 #      define C_RELATIVE_OFFSET_LOCAL_HEADER    38
143 
144    typedef uch   ec_byte_rec[ ECREC_SIZE+4 ];
145 /*     define SIGNATURE                         0   space-holder only */
146 #      define NUMBER_THIS_DISK                  4
147 #      define NUM_DISK_WITH_START_CENTRAL_DIR   6
148 #      define NUM_ENTRIES_CENTRL_DIR_THS_DISK   8
149 #      define TOTAL_ENTRIES_CENTRAL_DIR         10
150 #      define SIZE_CENTRAL_DIRECTORY            12
151 #      define OFFSET_START_CENTRAL_DIRECTORY    16
152 #      define ZIPFILE_COMMENT_LENGTH            20
153 
154 
155    typedef struct local_file_header {                 /* LOCAL */
156        uch version_needed_to_extract[2];
157        ush general_purpose_bit_flag;
158        ush compression_method;
159        ush last_mod_file_time;
160        ush last_mod_file_date;
161        ulg crc32;
162        ulg csize;
163        ulg ucsize;
164        ush filename_length;
165        ush extra_field_length;
166    } local_file_hdr;
167 
168    typedef struct central_directory_file_header {     /* CENTRAL */
169        uch version_made_by[2];
170        uch version_needed_to_extract[2];
171        ush general_purpose_bit_flag;
172        ush compression_method;
173        ush last_mod_file_time;
174        ush last_mod_file_date;
175        ulg crc32;
176        ulg csize;
177        ulg ucsize;
178        ush filename_length;
179        ush extra_field_length;
180        ush file_comment_length;
181        ush disk_number_start;
182        ush internal_file_attributes;
183        ulg external_file_attributes;
184        ulg relative_offset_local_header;
185    } cdir_file_hdr;
186 
187    typedef struct end_central_dir_record {            /* END CENTRAL */
188        ush number_this_disk;
189        ush num_disk_with_start_central_dir;
190        ush num_entries_centrl_dir_ths_disk;
191        ush total_entries_central_dir;
192        ulg size_central_directory;
193        ulg offset_start_central_directory;
194        ush zipfile_comment_length;
195    } ecdir_rec;
196 
197 
198 /************/
199 /*  Macros  */
200 /************/
201 
202 #ifndef MAX
203 #  define MAX(a,b)   ((a) > (b) ? (a) : (b))
204 #endif
205 #ifndef MIN
206 #  define MIN(a,b)   ((a) < (b) ? (a) : (b))
207 #endif
208 
209 
210 /***********************/
211 /* Prototypes          */
212 /***********************/
213 
214 static ush makeword (const uch *);
215 static ulg makelong (const uch *);
216 static long find_zip_file_start (int fd, long offset);
217 
218 /***********************/
219 /* Function makeword() */
220 /***********************/
221 
makeword(const uch * b)222 static ush makeword(const uch *b)
223 {
224     /*
225      * Convert Intel style 'short' integer to non-Intel non-16-bit
226      * host format.  This routine also takes care of byte-ordering.
227      */
228     return (ush)((b[1] << 8) | b[0]);
229 }
230 
231 
232 /***********************/
233 /* Function makelong() */
234 /***********************/
235 
236 static ulg
makelong(const uch * sig)237 makelong (const uch *sig)
238 {
239     /*
240      * Convert intel style 'long' variable to non-Intel non-16-bit
241      * host format.  This routine also takes care of byte-ordering.
242      */
243     return (((ulg)sig[3]) << 24)
244         + (((ulg)sig[2]) << 16)
245         + (((ulg)sig[1]) << 8)
246         + ((ulg)sig[0]);
247 }
248 
249 /* Examine file's header in zip file and return the offset of the
250    start of the actual data.  Return -1 on error.  OFFSET is the
251    offset from the beginning of the zip file of the file's header.  */
252 static long
find_zip_file_start(int fd,long offset)253 find_zip_file_start (int fd, long offset)
254 {
255   int filename_length, extra_field_length;
256   unsigned char buffer[LREC_SIZE + 4];
257 
258   if (lseek (fd, offset, SEEK_SET) < 0)
259     return -1;
260 
261   if (read (fd, buffer, LREC_SIZE + 4) != LREC_SIZE + 4)
262     return -1;
263 
264   if (buffer[0] != 'P' || strncmp ((const char *) &buffer[1], LOCAL_HDR_SIG, 3))
265     return -1;
266 
267   filename_length = makeword (&buffer[4 + L_FILENAME_LENGTH]);
268   extra_field_length = makeword (&buffer[4 + L_EXTRA_FIELD_LENGTH]);
269 
270   return offset + (4 + LREC_SIZE) + filename_length + extra_field_length;
271 }
272 
273 int
read_zip_archive(ZipFile * zipf)274 read_zip_archive (ZipFile *zipf)
275 {
276   int i;
277   int dir_last_pad;
278   char *dir_ptr;
279   char buffer[100];
280 
281   zipf->size = lseek (zipf->fd, 0L, SEEK_END);
282 
283   if (zipf->size < (ECREC_SIZE+4) || lseek (zipf->fd, (long)(-(ECREC_SIZE+4)), SEEK_CUR) <= 0)
284     return -1;
285   if (read (zipf->fd, buffer, ECREC_SIZE+4) != ECREC_SIZE+4)
286     return -2;
287   if (buffer[0] != 'P'
288       || strncmp ((const char *) &buffer[1], END_CENTRAL_SIG, 3))
289     {
290       /* We could not find the end-central-header signature, probably
291 	 because a zipfile comment is present. Scan backwards until we
292 	 find the signature. */
293       if (lseek (zipf->fd, (long)(-ECREC_SIZE), SEEK_END) <= 0)
294 	return -2;
295       while (buffer[0] != 'P'
296 	     || strncmp ((const char *) &buffer[1], END_CENTRAL_SIG, 3))
297 	{
298 	  if (lseek (zipf->fd, -5, SEEK_CUR) < 0)
299 	    return -2;
300 	  if (read (zipf->fd, buffer, 4) != 4)
301 	    return -2;
302 	}
303       if (read (zipf->fd, buffer + 4, ECREC_SIZE) != ECREC_SIZE)
304 	return -2;
305     }
306   zipf->count = makeword((const uch *) &buffer[TOTAL_ENTRIES_CENTRAL_DIR]);
307   zipf->dir_size = makelong((const uch *) &buffer[SIZE_CENTRAL_DIRECTORY]);
308   /* Allocate 1 more to allow appending '\0' to last filename. */
309   zipf->central_directory = XNEWVEC (char, zipf->dir_size + 1);
310   if (lseek (zipf->fd, -(zipf->dir_size+ECREC_SIZE+4), SEEK_CUR) < 0)
311     return -2;
312   if (read (zipf->fd, zipf->central_directory, zipf->dir_size) < 0)
313     return -2;
314 
315 #ifdef TEST
316   printf ("number_this_disk = %d\n", makeword(&buffer[NUMBER_THIS_DISK]));
317   printf ("num_disk_with_start_central_dir = %d\n", makeword(&buffer[NUM_DISK_WITH_START_CENTRAL_DIR]));
318 
319   printf ("num_entries_centrl_dir_ths_disk = %d\n",
320         makeword(&buffer[NUM_ENTRIES_CENTRL_DIR_THS_DISK]));
321   printf ("total_entries_central_dir = %d\n",
322         makeword(&buffer[TOTAL_ENTRIES_CENTRAL_DIR]));
323   printf ("size_central_directory = %d\n",
324         makelong((const uch *) &buffer[SIZE_CENTRAL_DIRECTORY]));
325   printf ("offset_start_central_directory = %d\n",
326         makelong((const uch *) &buffer[OFFSET_START_CENTRAL_DIRECTORY]));
327   printf ("zipfile_comment_length = %d\n",
328         makeword(&buffer[ZIPFILE_COMMENT_LENGTH]));
329 #endif
330 
331   dir_last_pad = 0;
332   dir_ptr = zipf->central_directory;
333   for (i = 0; i < zipf->count; i++)
334     {
335       ZipDirectory *zipd = (ZipDirectory*)(dir_ptr + dir_last_pad);
336       int compression_method = (int) dir_ptr[4+C_COMPRESSION_METHOD];
337       long size = makelong ((const uch *) &dir_ptr[4+C_COMPRESSED_SIZE]);
338       long uncompressed_size = makelong ((const uch *) &dir_ptr[4+C_UNCOMPRESSED_SIZE]);
339       long filename_length = makeword ((const uch *) &dir_ptr[4+C_FILENAME_LENGTH]);
340       long extra_field_length = makeword ((const uch *) &dir_ptr[4+C_EXTRA_FIELD_LENGTH]);
341       long file_offset = makelong ((const uch *) &dir_ptr[4+C_RELATIVE_OFFSET_LOCAL_HEADER]);
342       int unpadded_direntry_length;
343       if ((dir_ptr-zipf->central_directory)+filename_length+CREC_SIZE+4>zipf->dir_size)
344 	return -1;
345 
346       zipd->filename_length = filename_length;
347       zipd->compression_method = compression_method;
348       zipd->size = size;
349       zipd->uncompressed_size = uncompressed_size;
350       zipd->zipf = zipf;
351 #ifdef __GNUC__
352 #define DIR_ALIGN __alignof__(ZipDirectory)
353 #else
354 #define DIR_ALIGN sizeof(long)
355 #endif
356       zipd->filestart = find_zip_file_start (zipf->fd, file_offset);
357       zipd->filename_offset = CREC_SIZE+4 - dir_last_pad;
358       unpadded_direntry_length
359 	  = zipd->filename_offset + zipd->filename_length + extra_field_length;
360       zipd->direntry_size =
361 	((unpadded_direntry_length + DIR_ALIGN) / DIR_ALIGN) * DIR_ALIGN;
362       dir_last_pad = zipd->direntry_size - unpadded_direntry_length;
363       dir_ptr = (char*)zipd + unpadded_direntry_length;
364       *dir_ptr = '\0';
365     }
366   return 0;
367 }
368 
369 #ifdef TEST
main(void)370 main (void)
371 {
372   ZipFile zipf[1];
373   ZipDirectory *zipd;
374   int i;
375 
376   zipf->fd = 0;
377 
378   i = read_zip_archive (zipf);
379   if (i)
380     {
381       fprintf (stderr, "Bad zip file.\n");
382       exit (i);
383     }
384 
385   zipd = (ZipDirectory*) zipf->central_directory;
386   for (i = 0; i < zipf->count; i++, zipd = ZIPDIR_NEXT (zipd))
387     {
388       printf ("%d: size:%d, name(#%d)%s, offset:%d\n",
389 	      i, zipd->size, zipd->filename_length,
390 	      ZIPDIR_FILENAME (zipd),
391 	      zipd->filestart);
392     }
393 }
394 #endif
395