1 /*- 2 * Copyright (c) 2003-2007 Tim Kientzle 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED 27 #define ARCHIVE_READ_PRIVATE_H_INCLUDED 28 29 #ifndef __LIBARCHIVE_BUILD 30 #ifndef __LIBARCHIVE_TEST 31 #error This header is only to be used internally to libarchive. 32 #endif 33 #endif 34 35 #include "archive.h" 36 #include "archive_string.h" 37 #include "archive_private.h" 38 39 struct archive_read; 40 struct archive_read_filter_bidder; 41 struct archive_read_filter; 42 43 struct archive_read_filter_bidder_vtable { 44 /* Taste the upstream filter to see if we handle this. */ 45 int (*bid)(struct archive_read_filter_bidder *, 46 struct archive_read_filter *); 47 /* Initialize a newly-created filter. */ 48 int (*init)(struct archive_read_filter *); 49 /* Release the bidder's configuration data. */ 50 void (*free)(struct archive_read_filter_bidder *); 51 }; 52 53 /* 54 * How bidding works for filters: 55 * * The bid manager initializes the client-provided reader as the 56 * first filter. 57 * * It invokes the bidder for each registered filter with the 58 * current head filter. 59 * * The bidders can use archive_read_filter_ahead() to peek ahead 60 * at the incoming data to compose their bids. 61 * * The bid manager creates a new filter structure for the winning 62 * bidder and gives the winning bidder a chance to initialize it. 63 * * The new filter becomes the new top filter and we repeat the 64 * process. 65 * This ends only when no bidder provides a non-zero bid. Then 66 * we perform a similar dance with the registered format handlers. 67 */ 68 struct archive_read_filter_bidder { 69 /* Configuration data for the bidder. */ 70 void *data; 71 /* Name of the filter */ 72 const char *name; 73 const struct archive_read_filter_bidder_vtable *vtable; 74 }; 75 76 struct archive_read_filter_vtable { 77 /* Return next block. */ 78 ssize_t (*read)(struct archive_read_filter *, const void **); 79 /* Close (just this filter) and free(self). */ 80 int (*close)(struct archive_read_filter *self); 81 /* Read any header metadata if available. */ 82 int (*read_header)(struct archive_read_filter *self, struct archive_entry *entry); 83 }; 84 85 /* 86 * This structure is allocated within the archive_read core 87 * and initialized by archive_read and the init() method of the 88 * corresponding bidder above. 89 */ 90 struct archive_read_filter { 91 int64_t position; 92 /* Essentially all filters will need these values, so 93 * just declare them here. */ 94 struct archive_read_filter_bidder *bidder; /* My bidder. */ 95 struct archive_read_filter *upstream; /* Who I read from. */ 96 struct archive_read *archive; /* Associated archive. */ 97 const struct archive_read_filter_vtable *vtable; 98 /* My private data. */ 99 void *data; 100 101 const char *name; 102 int code; 103 int can_skip; 104 int can_seek; 105 106 /* Used by reblocking logic. */ 107 char *buffer; 108 size_t buffer_size; 109 char *next; /* Current read location. */ 110 size_t avail; /* Bytes in my buffer. */ 111 const void *client_buff; /* Client buffer information. */ 112 size_t client_total; 113 const char *client_next; 114 size_t client_avail; 115 char end_of_file; 116 char closed; 117 char fatal; 118 }; 119 120 /* 121 * The client looks a lot like a filter, so we just wrap it here. 122 * 123 * TODO: Make archive_read_filter and archive_read_client identical so 124 * that users of the library can easily register their own 125 * transformation filters. This will probably break the API/ABI and 126 * so should be deferred at least until libarchive 3.0. 127 */ 128 struct archive_read_data_node { 129 int64_t begin_position; 130 int64_t total_size; 131 void *data; 132 }; 133 struct archive_read_client { 134 archive_open_callback *opener; 135 archive_read_callback *reader; 136 archive_skip_callback *skipper; 137 archive_seek_callback *seeker; 138 archive_close_callback *closer; 139 archive_switch_callback *switcher; 140 unsigned int nodes; 141 unsigned int cursor; 142 int64_t position; 143 struct archive_read_data_node *dataset; 144 }; 145 struct archive_read_passphrase { 146 char *passphrase; 147 struct archive_read_passphrase *next; 148 }; 149 150 struct archive_read_extract { 151 struct archive *ad; /* archive_write_disk object */ 152 153 /* Progress function invoked during extract. */ 154 void (*extract_progress)(void *); 155 void *extract_progress_user_data; 156 }; 157 158 struct archive_read { 159 struct archive archive; 160 161 struct archive_entry *entry; 162 163 /* Dev/ino of the archive being read/written. */ 164 int skip_file_set; 165 int64_t skip_file_dev; 166 int64_t skip_file_ino; 167 168 /* Callbacks to open/read/write/close client archive streams. */ 169 struct archive_read_client client; 170 171 /* Registered filter bidders. */ 172 struct archive_read_filter_bidder bidders[16]; 173 174 /* Last filter in chain */ 175 struct archive_read_filter *filter; 176 177 /* Whether to bypass filter bidding process */ 178 int bypass_filter_bidding; 179 180 /* File offset of beginning of most recently-read header. */ 181 int64_t header_position; 182 183 /* Nodes and offsets of compressed data block */ 184 unsigned int data_start_node; 185 unsigned int data_end_node; 186 187 /* 188 * Format detection is mostly the same as compression 189 * detection, with one significant difference: The bidders 190 * use the read_ahead calls above to examine the stream rather 191 * than having the supervisor hand them a block of data to 192 * examine. 193 */ 194 195 struct archive_format_descriptor { 196 void *data; 197 const char *name; 198 int (*bid)(struct archive_read *, int best_bid); 199 int (*options)(struct archive_read *, const char *key, 200 const char *value); 201 int (*read_header)(struct archive_read *, struct archive_entry *); 202 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *); 203 int (*read_data_skip)(struct archive_read *); 204 int64_t (*seek_data)(struct archive_read *, int64_t, int); 205 int (*cleanup)(struct archive_read *); 206 int (*format_capabilties)(struct archive_read *); 207 int (*has_encrypted_entries)(struct archive_read *); 208 } formats[16]; 209 struct archive_format_descriptor *format; /* Active format. */ 210 211 /* 212 * Various information needed by archive_extract. 213 */ 214 struct archive_read_extract *extract; 215 int (*cleanup_archive_extract)(struct archive_read *); 216 217 /* 218 * Decryption passphrase. 219 */ 220 struct { 221 struct archive_read_passphrase *first; 222 struct archive_read_passphrase **last; 223 int candidate; 224 archive_passphrase_callback *callback; 225 void *client_data; 226 } passphrases; 227 }; 228 229 int __archive_read_register_format(struct archive_read *a, 230 void *format_data, 231 const char *name, 232 int (*bid)(struct archive_read *, int), 233 int (*options)(struct archive_read *, const char *, const char *), 234 int (*read_header)(struct archive_read *, struct archive_entry *), 235 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *), 236 int (*read_data_skip)(struct archive_read *), 237 int64_t (*seek_data)(struct archive_read *, int64_t, int), 238 int (*cleanup)(struct archive_read *), 239 int (*format_capabilities)(struct archive_read *), 240 int (*has_encrypted_entries)(struct archive_read *)); 241 242 int __archive_read_register_bidder(struct archive_read *a, 243 void *bidder_data, 244 const char *name, 245 const struct archive_read_filter_bidder_vtable *vtable); 246 247 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 248 const void *__archive_read_filter_ahead(struct archive_read_filter *, 249 size_t, ssize_t *); 250 int64_t __archive_read_seek(struct archive_read*, int64_t, int); 251 int64_t __archive_read_filter_seek(struct archive_read_filter *, int64_t, int); 252 int64_t __archive_read_consume(struct archive_read *, int64_t); 253 int64_t __archive_read_filter_consume(struct archive_read_filter *, int64_t); 254 int __archive_read_header(struct archive_read *, struct archive_entry *); 255 int __archive_read_program(struct archive_read_filter *, const char *); 256 void __archive_read_free_filters(struct archive_read *); 257 struct archive_read_extract *__archive_read_get_extract(struct archive_read *); 258 259 260 /* 261 * Get a decryption passphrase. 262 */ 263 void __archive_read_reset_passphrase(struct archive_read *a); 264 const char * __archive_read_next_passphrase(struct archive_read *a); 265 #endif 266