1 /*
2  * Copyright (c) 2019 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 
19 #include <errno.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <sha1.h>
24 #include <zlib.h>
25 #include <time.h>
26 
27 #include "got_error.h"
28 #include "got_object.h"
29 #include "got_path.h"
30 
31 #include "got_lib_deflate.h"
32 
33 #ifndef MIN
34 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
35 #endif
36 
37 const struct got_error *
38 got_deflate_init(struct got_deflate_buf *zb, uint8_t *outbuf, size_t bufsize)
39 {
40 	const struct got_error *err = NULL;
41 	int zerr;
42 
43 	memset(&zb->z, 0, sizeof(zb->z));
44 
45 	zb->z.zalloc = Z_NULL;
46 	zb->z.zfree = Z_NULL;
47 	zerr = deflateInit(&zb->z, Z_DEFAULT_COMPRESSION);
48 	if (zerr != Z_OK) {
49 		if  (zerr == Z_ERRNO)
50 			return got_error_from_errno("deflateInit");
51 		if  (zerr == Z_MEM_ERROR) {
52 			errno = ENOMEM;
53 			return got_error_from_errno("deflateInit");
54 		}
55 		return got_error(GOT_ERR_COMPRESSION);
56 	}
57 
58 	zb->inlen = zb->outlen = bufsize;
59 
60 	zb->inbuf = calloc(1, zb->inlen);
61 	if (zb->inbuf == NULL) {
62 		err = got_error_from_errno("calloc");
63 		goto done;
64 	}
65 
66 	zb->flags = 0;
67 	if (outbuf == NULL) {
68 		zb->outbuf = calloc(1, zb->outlen);
69 		if (zb->outbuf == NULL) {
70 			err = got_error_from_errno("calloc");
71 			goto done;
72 		}
73 		zb->flags |= GOT_DEFLATE_F_OWN_OUTBUF;
74 	} else
75 		zb->outbuf = outbuf;
76 done:
77 	if (err)
78 		got_deflate_end(zb);
79 	return err;
80 }
81 
82 static void
83 csum_output(struct got_deflate_checksum *csum, const uint8_t *buf, size_t len)
84 {
85 	if (csum->output_crc)
86 		*csum->output_crc = crc32(*csum->output_crc, buf, len);
87 
88 	if (csum->output_sha1)
89 		SHA1Update(csum->output_sha1, buf, len);
90 }
91 
92 const struct got_error *
93 got_deflate_read(struct got_deflate_buf *zb, FILE *f, off_t len,
94     size_t *outlenp, off_t *consumed)
95 {
96 	size_t last_total_out = zb->z.total_out;
97 	z_stream *z = &zb->z;
98 	int ret = Z_ERRNO;
99 
100 	z->next_out = zb->outbuf;
101 	z->avail_out = zb->outlen;
102 
103 	*outlenp = 0;
104 	*consumed = 0;
105 	do {
106 		size_t last_total_in = z->total_in;
107 		if (z->avail_in == 0) {
108 			size_t n = 0;
109 			if (*consumed < len) {
110 				n = fread(zb->inbuf, 1,
111 				    MIN(zb->inlen, len - *consumed), f);
112 			}
113 			if (n == 0) {
114 				if (ferror(f))
115 					return got_ferror(f, GOT_ERR_IO);
116 				/* EOF */
117 				ret = deflate(z, Z_FINISH);
118 				break;
119 			}
120 			z->next_in = zb->inbuf;
121 			z->avail_in = n;
122 		}
123 		ret = deflate(z, Z_NO_FLUSH);
124 		*consumed += z->total_in - last_total_in;
125 	} while (ret == Z_OK && z->avail_out > 0);
126 
127 	if (ret == Z_OK) {
128 		zb->flags |= GOT_DEFLATE_F_HAVE_MORE;
129 	} else {
130 		if (ret != Z_STREAM_END)
131 			return got_error(GOT_ERR_COMPRESSION);
132 		zb->flags &= ~GOT_DEFLATE_F_HAVE_MORE;
133 	}
134 
135 	*outlenp = z->total_out - last_total_out;
136 	return NULL;
137 }
138 
139 const struct got_error *
140 got_deflate_read_mmap(struct got_deflate_buf *zb, uint8_t *map, size_t offset,
141     size_t len, size_t *outlenp, size_t *consumed)
142 {
143 	z_stream *z = &zb->z;
144 	size_t last_total_out = z->total_out;
145 	int ret = Z_ERRNO;
146 
147 	z->next_out = zb->outbuf;
148 	z->avail_out = zb->outlen;
149 
150 	*outlenp = 0;
151 	*consumed = 0;
152 	do {
153 		size_t last_total_in = z->total_in;
154 		if (z->avail_in == 0) {
155 			z->next_in = map + offset + *consumed;
156 			if (len - *consumed > UINT_MAX)
157 				z->avail_in = UINT_MAX;
158 			else
159 				z->avail_in = len - *consumed;
160 			if (z->avail_in == 0) {
161 				/* EOF */
162 				ret = deflate(z, Z_FINISH);
163 				break;
164 			}
165 		}
166 		ret = deflate(z, Z_NO_FLUSH);
167 		*consumed += z->total_in - last_total_in;
168 	} while (ret == Z_OK && z->avail_out > 0);
169 
170 	if (ret == Z_OK) {
171 		zb->flags |= GOT_DEFLATE_F_HAVE_MORE;
172 	} else {
173 		if (ret != Z_STREAM_END)
174 			return got_error(GOT_ERR_COMPRESSION);
175 		zb->flags &= ~GOT_DEFLATE_F_HAVE_MORE;
176 	}
177 
178 	*outlenp = z->total_out - last_total_out;
179 	return NULL;
180 }
181 
182 void
183 got_deflate_end(struct got_deflate_buf *zb)
184 {
185 	free(zb->inbuf);
186 	if (zb->flags & GOT_DEFLATE_F_OWN_OUTBUF)
187 		free(zb->outbuf);
188 	deflateEnd(&zb->z);
189 }
190 
191 const struct got_error *
192 got_deflate_to_file(off_t *outlen, FILE *infile, off_t len,
193     FILE *outfile, struct got_deflate_checksum *csum)
194 {
195 	const struct got_error *err;
196 	size_t avail;
197 	off_t consumed;
198 	struct got_deflate_buf zb;
199 
200 	err = got_deflate_init(&zb, NULL, GOT_DEFLATE_BUFSIZE);
201 	if (err)
202 		goto done;
203 
204 	*outlen = 0;
205 
206 	do {
207 		err = got_deflate_read(&zb, infile, len, &avail, &consumed);
208 		if (err)
209 			goto done;
210 		len -= consumed;
211 		if (avail > 0) {
212 			size_t n;
213 			n = fwrite(zb.outbuf, avail, 1, outfile);
214 			if (n != 1) {
215 				err = got_ferror(outfile, GOT_ERR_IO);
216 				goto done;
217 			}
218 			if (csum)
219 				csum_output(csum, zb.outbuf, avail);
220 			*outlen += avail;
221 		}
222 	} while (zb.flags & GOT_DEFLATE_F_HAVE_MORE);
223 
224 done:
225 	got_deflate_end(&zb);
226 	return err;
227 }
228 
229 const struct got_error *
230 got_deflate_to_file_mmap(off_t *outlen, uint8_t *map, size_t offset,
231     size_t len, FILE *outfile, struct got_deflate_checksum *csum)
232 {
233 	const struct got_error *err;
234 	size_t avail, consumed;
235 	struct got_deflate_buf zb;
236 
237 	err = got_deflate_init(&zb, NULL, GOT_DEFLATE_BUFSIZE);
238 	if (err)
239 		goto done;
240 
241 	*outlen = 0;
242 	do {
243 		err = got_deflate_read_mmap(&zb, map, offset, len, &avail,
244 		    &consumed);
245 		if (err)
246 			goto done;
247 		offset += consumed;
248 		len -= consumed;
249 		if (avail > 0) {
250 			size_t n;
251 			n = fwrite(zb.outbuf, avail, 1, outfile);
252 			if (n != 1) {
253 				err = got_ferror(outfile, GOT_ERR_IO);
254 				goto done;
255 			}
256 			if (csum)
257 				csum_output(csum, zb.outbuf, avail);
258 			*outlen += avail;
259 		}
260 	} while (zb.flags & GOT_DEFLATE_F_HAVE_MORE);
261 
262 done:
263 	got_deflate_end(&zb);
264 	return err;
265 }