2 efd2a263 2018-01-19 stsp * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
4 efd2a263 2018-01-19 stsp * Permission to use, copy, modify, and distribute this software for any
5 efd2a263 2018-01-19 stsp * purpose with or without fee is hereby granted, provided that the above
6 efd2a263 2018-01-19 stsp * copyright notice and this permission notice appear in all copies.
8 efd2a263 2018-01-19 stsp * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 efd2a263 2018-01-19 stsp * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 efd2a263 2018-01-19 stsp * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 efd2a263 2018-01-19 stsp * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 efd2a263 2018-01-19 stsp * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 efd2a263 2018-01-19 stsp * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 efd2a263 2018-01-19 stsp * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 efd2a263 2018-01-19 stsp #include <sys/queue.h>
19 efd2a263 2018-01-19 stsp #include <stdio.h>
20 96f5e8b3 2018-01-23 stsp #include <stdlib.h>
21 96f5e8b3 2018-01-23 stsp #include <string.h>
22 efd2a263 2018-01-19 stsp #include <zlib.h>
23 efd2a263 2018-01-19 stsp #include <sha1.h>
25 efd2a263 2018-01-19 stsp #include "got_error.h"
26 efd2a263 2018-01-19 stsp #include "got_repository.h"
27 efd2a263 2018-01-19 stsp #include "got_object.h"
29 efd2a263 2018-01-19 stsp #include "delta.h"
30 885d3e02 2018-01-27 stsp #include "zb.h"
33 885d3e02 2018-01-27 stsp #define MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
36 c3703302 2018-01-23 stsp struct got_delta *
37 c3703302 2018-01-23 stsp got_delta_open(const char *path_packfile, int type, off_t offset,
38 5a2e13f7 2018-01-23 stsp size_t size)
40 c3703302 2018-01-23 stsp struct got_delta *delta;
42 c3703302 2018-01-23 stsp delta = calloc(1, sizeof(*delta));
43 c3703302 2018-01-23 stsp if (delta == NULL)
44 96f5e8b3 2018-01-23 stsp return NULL;
46 c3703302 2018-01-23 stsp delta->path_packfile = strdup(path_packfile);
47 c3703302 2018-01-23 stsp if (delta->path_packfile == NULL) {
48 c3703302 2018-01-23 stsp free(delta);
49 96f5e8b3 2018-01-23 stsp return NULL;
51 c3703302 2018-01-23 stsp delta->type = type;
52 c3703302 2018-01-23 stsp delta->offset = offset;
53 c3703302 2018-01-23 stsp delta->size = size;
54 c3703302 2018-01-23 stsp return delta;
58 c3703302 2018-01-23 stsp got_delta_close(struct got_delta *delta)
60 c3703302 2018-01-23 stsp free(delta->path_packfile);
61 c3703302 2018-01-23 stsp free(delta);
65 efd2a263 2018-01-19 stsp const struct got_error *
66 96f5e8b3 2018-01-23 stsp got_delta_chain_get_base_type(int *type, struct got_delta_chain *deltas)
68 c3703302 2018-01-23 stsp struct got_delta *delta;
70 6691714a 2018-01-23 stsp /* The first delta in the chain should represent the base object. */
71 6691714a 2018-01-23 stsp delta = SIMPLEQ_FIRST(&deltas->entries);
72 6691714a 2018-01-23 stsp if (delta->type == GOT_OBJ_TYPE_COMMIT ||
73 6691714a 2018-01-23 stsp delta->type == GOT_OBJ_TYPE_TREE ||
74 6691714a 2018-01-23 stsp delta->type == GOT_OBJ_TYPE_BLOB ||
75 6691714a 2018-01-23 stsp delta->type == GOT_OBJ_TYPE_TAG) {
76 6691714a 2018-01-23 stsp *type = delta->type;
77 6691714a 2018-01-23 stsp return NULL;
80 96f5e8b3 2018-01-23 stsp return got_error(GOT_ERR_BAD_DELTA_CHAIN);
83 885d3e02 2018-01-27 stsp /* Fetch another (required) byte from the delta stream. */
84 885d3e02 2018-01-27 stsp static const struct got_error *
85 885d3e02 2018-01-27 stsp next_delta_byte(const uint8_t **p, size_t *remain)
87 885d3e02 2018-01-27 stsp if (--(*remain) == 0)
88 885d3e02 2018-01-27 stsp return got_error(GOT_ERR_BAD_DELTA);
90 885d3e02 2018-01-27 stsp return NULL;
93 885d3e02 2018-01-27 stsp static const struct got_error *
94 885d3e02 2018-01-27 stsp parse_size(uint64_t *size, const uint8_t **p, size_t *remain)
96 885d3e02 2018-01-27 stsp const struct got_error *err = NULL;
101 885d3e02 2018-01-27 stsp /* We do not support size values which don't fit in 64 bit. */
103 885d3e02 2018-01-27 stsp return got_error(GOT_ERR_NO_SPACE);
105 885d3e02 2018-01-27 stsp if (i == 0)
106 885d3e02 2018-01-27 stsp *size = ((**p) & GOT_DELTA_SIZE_VAL_MASK);
108 885d3e02 2018-01-27 stsp size_t shift = GOT_DELTA_SIZE_SHIFT * i;
109 885d3e02 2018-01-27 stsp *size |= (((**p) & GOT_DELTA_SIZE_VAL_MASK) << shift);
112 885d3e02 2018-01-27 stsp if (((**p) & GOT_DELTA_SIZE_MORE) == 0)
115 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
116 885d3e02 2018-01-27 stsp } while (err == NULL);
118 885d3e02 2018-01-27 stsp return err;
121 885d3e02 2018-01-27 stsp static const struct got_error *
122 885d3e02 2018-01-27 stsp parse_opcode(off_t *offset, size_t *len, const uint8_t **p, size_t *remain)
124 885d3e02 2018-01-27 stsp const struct got_error *err = NULL;
125 885d3e02 2018-01-27 stsp off_t o = 0;
126 885d3e02 2018-01-27 stsp size_t l = 0;
127 885d3e02 2018-01-27 stsp uint8_t opcode = **p;
129 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_OFF1) {
130 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
132 885d3e02 2018-01-27 stsp return err;
133 885d3e02 2018-01-27 stsp o = (off_t)(**p);
135 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_OFF2) {
136 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
138 885d3e02 2018-01-27 stsp return err;
139 885d3e02 2018-01-27 stsp o |= ((off_t)(**p)) << 8;
141 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_OFF3) {
142 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
144 885d3e02 2018-01-27 stsp return err;
145 885d3e02 2018-01-27 stsp o |= ((off_t)(**p)) << 16;
147 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_OFF4) {
148 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
150 885d3e02 2018-01-27 stsp return err;
151 885d3e02 2018-01-27 stsp o |= ((off_t)(**p)) << 24;
154 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_LEN1) {
155 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
157 885d3e02 2018-01-27 stsp return err;
158 885d3e02 2018-01-27 stsp l = (off_t)(**p);
160 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_LEN2) {
161 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
163 885d3e02 2018-01-27 stsp return err;
164 885d3e02 2018-01-27 stsp l |= ((off_t)(**p)) << 8;
166 885d3e02 2018-01-27 stsp if (opcode & GOT_DELTA_COPY_LEN3) {
167 885d3e02 2018-01-27 stsp err = next_delta_byte(p, remain);
169 885d3e02 2018-01-27 stsp return err;
170 885d3e02 2018-01-27 stsp l |= ((off_t)(**p)) << 16;
173 885d3e02 2018-01-27 stsp if (o == 0)
174 885d3e02 2018-01-27 stsp o = GOT_DELTA_COPY_DEFAULT_OFF;
175 885d3e02 2018-01-27 stsp if (l == 0)
176 885d3e02 2018-01-27 stsp l = GOT_DELTA_COPY_DEFAULT_LEN;
178 885d3e02 2018-01-27 stsp *offset = o;
180 885d3e02 2018-01-27 stsp return NULL;
183 885d3e02 2018-01-27 stsp static const struct got_error *
184 885d3e02 2018-01-27 stsp copy_from_base(FILE *base_file, off_t offset, size_t size, FILE *outfile)
186 885d3e02 2018-01-27 stsp if (fseeko(base_file, offset, SEEK_SET) != 0)
187 885d3e02 2018-01-27 stsp return got_error_from_errno();
189 885d3e02 2018-01-27 stsp while (size > 0) {
190 885d3e02 2018-01-27 stsp uint8_t data[2048];
191 885d3e02 2018-01-27 stsp size_t len = MIN(size, sizeof(data));
194 885d3e02 2018-01-27 stsp n = fread(data, len, 1, base_file);
195 885d3e02 2018-01-27 stsp if (n != 1)
196 885d3e02 2018-01-27 stsp return got_ferror(base_file, GOT_ERR_IO);
198 885d3e02 2018-01-27 stsp n = fwrite(data, len, 1, outfile);
199 885d3e02 2018-01-27 stsp if (n != 1)
200 885d3e02 2018-01-27 stsp return got_ferror(outfile, GOT_ERR_IO);
202 885d3e02 2018-01-27 stsp size -= len;
205 885d3e02 2018-01-27 stsp return NULL;
208 885d3e02 2018-01-27 stsp static const struct got_error *
209 885d3e02 2018-01-27 stsp copy_from_delta(const uint8_t **p, size_t *remain, size_t len, FILE *outfile)
213 885d3e02 2018-01-27 stsp if (*remain < len)
214 885d3e02 2018-01-27 stsp return got_error(GOT_ERR_BAD_DELTA);
216 885d3e02 2018-01-27 stsp n = fwrite(*p, len, 1, outfile);
217 885d3e02 2018-01-27 stsp if (n != 1)
218 885d3e02 2018-01-27 stsp return got_ferror(outfile, GOT_ERR_IO);
221 885d3e02 2018-01-27 stsp *remain -= len;
222 885d3e02 2018-01-27 stsp return NULL;
225 885d3e02 2018-01-27 stsp const struct got_error *
226 885d3e02 2018-01-27 stsp got_delta_apply(FILE *base_compressed, const uint8_t *delta_buf,
227 885d3e02 2018-01-27 stsp size_t delta_len, FILE *outfile)
229 885d3e02 2018-01-27 stsp const struct got_error *err = NULL;
230 885d3e02 2018-01-27 stsp FILE *base_file = NULL;
231 885d3e02 2018-01-27 stsp uint64_t base_size, result_size;
232 885d3e02 2018-01-27 stsp size_t remain, outsize = 0;
233 885d3e02 2018-01-27 stsp const uint8_t *p;
235 885d3e02 2018-01-27 stsp if (delta_len < GOT_DELTA_STREAM_LENGTH_MIN)
236 885d3e02 2018-01-27 stsp return got_error(GOT_ERR_BAD_DELTA);
238 885d3e02 2018-01-27 stsp p = delta_buf;
239 885d3e02 2018-01-27 stsp remain = delta_len;
241 885d3e02 2018-01-27 stsp /* Read the two size fields at the beginning of the stream. */
242 885d3e02 2018-01-27 stsp err = parse_size(&base_size, &p, &remain);
244 885d3e02 2018-01-27 stsp return err;
245 885d3e02 2018-01-27 stsp err = next_delta_byte(&p, &remain);
247 885d3e02 2018-01-27 stsp return err;
248 885d3e02 2018-01-27 stsp err = parse_size(&result_size, &p, &remain);
250 885d3e02 2018-01-27 stsp return err;
252 885d3e02 2018-01-27 stsp /* Decode and execute copy instructions from the delta stream. */
253 885d3e02 2018-01-27 stsp err = next_delta_byte(&p, &remain);
254 885d3e02 2018-01-27 stsp while (err == NULL) {
255 824801e7 2018-01-27 stsp if (*p & GOT_DELTA_BASE_COPY) {
256 885d3e02 2018-01-27 stsp off_t offset = 0;
257 885d3e02 2018-01-27 stsp size_t len = 0;
258 885d3e02 2018-01-27 stsp err = parse_opcode(&offset, &len, &p, &remain);
261 885d3e02 2018-01-27 stsp if (base_file == NULL) {
262 885d3e02 2018-01-27 stsp size_t inflated_size;
263 885d3e02 2018-01-27 stsp err = got_inflate_to_tempfile(&base_file,
264 885d3e02 2018-01-27 stsp &inflated_size, base_compressed);
267 885d3e02 2018-01-27 stsp if (inflated_size != base_size) {
268 885d3e02 2018-01-27 stsp err = got_error(GOT_ERR_BAD_DELTA);
272 885d3e02 2018-01-27 stsp err = copy_from_base(base_file, offset, len, outfile);
273 885d3e02 2018-01-27 stsp if (err == NULL)
274 885d3e02 2018-01-27 stsp outsize += len;
276 885d3e02 2018-01-27 stsp size_t len = (size_t)*p;
277 885d3e02 2018-01-27 stsp if (len == 0) {
278 885d3e02 2018-01-27 stsp err = got_error(GOT_ERR_BAD_DELTA);
281 885d3e02 2018-01-27 stsp err = next_delta_byte(&p, &remain);
283 885d3e02 2018-01-27 stsp return err;
284 885d3e02 2018-01-27 stsp err = copy_from_delta(&p, &remain, len, outfile);
285 885d3e02 2018-01-27 stsp if (err == NULL)
286 885d3e02 2018-01-27 stsp outsize += len;
289 885d3e02 2018-01-27 stsp if (err == NULL) {
290 885d3e02 2018-01-27 stsp if (remain == 0)
292 885d3e02 2018-01-27 stsp /* Fetch the next instruction. */
298 885d3e02 2018-01-27 stsp if (outsize != result_size)
299 885d3e02 2018-01-27 stsp err = got_error(GOT_ERR_BAD_DELTA);
301 885d3e02 2018-01-27 stsp if (base_file)
302 885d3e02 2018-01-27 stsp fclose(base_file);
303 885d3e02 2018-01-27 stsp if (err == NULL)
304 885d3e02 2018-01-27 stsp rewind(outfile);
305 885d3e02 2018-01-27 stsp return err;
