1 /*
2  * Copyright (c) 2018 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 <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #include <sha1.h>
23 #include <zlib.h>
24 
25 #include "got_error.h"
26 #include "got_object.h"
27 
28 #include "got_lib_path.h"
29 #include "got_lib_zbuf.h"
30 
31 const struct got_error *
32 got_inflate_init(struct got_zstream_buf *zb, uint8_t *outbuf, size_t bufsize)
33 {
34 	const struct got_error *err = NULL;
35 
36 	memset(zb, 0, sizeof(*zb));
37 
38 	zb->z.zalloc = Z_NULL;
39 	zb->z.zfree = Z_NULL;
40 	if (inflateInit(&zb->z) != Z_OK) {
41 		err = got_error(GOT_ERR_IO);
42 		goto done;
43 	}
44 
45 	zb->inlen = zb->outlen = bufsize;
46 
47 	zb->inbuf = calloc(1, zb->inlen);
48 	if (zb->inbuf == NULL) {
49 		err = got_error_from_errno();
50 		goto done;
51 	}
52 
53 	if (outbuf == NULL) {
54 		zb->outbuf = calloc(1, zb->outlen);
55 		if (zb->outbuf == NULL) {
56 			err = got_error_from_errno();
57 			goto done;
58 		}
59 		zb->flags |= GOT_ZSTREAM_F_OWN_OUTBUF;
60 	} else
61 		zb->outbuf = outbuf;
62 
63 done:
64 	if (err)
65 		got_inflate_end(zb);
66 	return err;
67 }
68 
69 const struct got_error *
70 got_inflate_read(struct got_zstream_buf *zb, FILE *f, size_t *outlenp)
71 {
72 	size_t last_total_out = zb->z.total_out;
73 	z_stream *z = &zb->z;
74 	int ret = Z_ERRNO;
75 
76 	z->next_out = zb->outbuf;
77 	z->avail_out = zb->outlen;
78 
79 	*outlenp = 0;
80 	do {
81 		if (z->avail_in == 0) {
82 			size_t n = fread(zb->inbuf, 1, zb->inlen, f);
83 			if (n == 0) {
84 				if (ferror(f))
85 					return got_ferror(f, GOT_ERR_IO);
86 				/* EOF */
87 				ret = Z_STREAM_END;
88 				break;
89 			}
90 			z->next_in = zb->inbuf;
91 			z->avail_in = n;
92 		}
93 		ret = inflate(z, Z_SYNC_FLUSH);
94 	} while (ret == Z_OK && z->avail_out > 0);
95 
96 	if (ret == Z_OK) {
97 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
98 	} else {
99 		if (ret != Z_STREAM_END)
100 			return got_error(GOT_ERR_DECOMPRESSION);
101 		zb->flags &= ~GOT_ZSTREAM_F_HAVE_MORE;
102 	}
103 
104 	*outlenp = z->total_out - last_total_out;
105 	return NULL;
106 }
107 
108 const struct got_error *
109 got_inflate_read_fd(struct got_zstream_buf *zb, int fd, size_t *outlenp)
110 {
111 	size_t last_total_out = zb->z.total_out;
112 	z_stream *z = &zb->z;
113 	int ret = Z_ERRNO;
114 
115 	z->next_out = zb->outbuf;
116 	z->avail_out = zb->outlen;
117 
118 	*outlenp = 0;
119 	do {
120 		if (z->avail_in == 0) {
121 			ssize_t n = read(fd, zb->inbuf, zb->inlen);
122 			if (n < 0)
123 				return got_error_from_errno();
124 			else if (n == 0) {
125 				/* EOF */
126 				ret = Z_STREAM_END;
127 				break;
128 			}
129 			z->next_in = zb->inbuf;
130 			z->avail_in = n;
131 		}
132 		ret = inflate(z, Z_SYNC_FLUSH);
133 	} while (ret == Z_OK && z->avail_out > 0);
134 
135 	if (ret == Z_OK) {
136 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
137 	} else {
138 		if (ret != Z_STREAM_END)
139 			return got_error(GOT_ERR_DECOMPRESSION);
140 		zb->flags &= ~GOT_ZSTREAM_F_HAVE_MORE;
141 	}
142 
143 	*outlenp = z->total_out - last_total_out;
144 	return NULL;
145 }
146 
147 void
148 got_inflate_end(struct got_zstream_buf *zb)
149 {
150 	free(zb->inbuf);
151 	if (zb->flags & GOT_ZSTREAM_F_OWN_OUTBUF)
152 		free(zb->outbuf);
153 	inflateEnd(&zb->z);
154 }
155 
156 const struct got_error *
157 got_inflate_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f)
158 {
159 	const struct got_error *err;
160 	size_t avail;
161 	struct got_zstream_buf zb;
162 	void *newbuf;
163 
164 	*outbuf = calloc(1, GOT_ZSTREAM_BUFSIZE);
165 	if (*outbuf == NULL)
166 		return got_error_from_errno();
167 	err = got_inflate_init(&zb, *outbuf, GOT_ZSTREAM_BUFSIZE);
168 	if (err)
169 		return err;
170 
171 	*outlen = 0;
172 
173 	do {
174 		err = got_inflate_read(&zb, f, &avail);
175 		if (err)
176 			return err;
177 		*outlen += avail;
178 		if (zb.flags & GOT_ZSTREAM_F_HAVE_MORE) {
179 			newbuf = reallocarray(*outbuf, 1,
180 			    *outlen + GOT_ZSTREAM_BUFSIZE);
181 			if (newbuf == NULL) {
182 				err = got_error_from_errno();
183 				free(*outbuf);
184 				*outbuf = NULL;
185 				*outlen = 0;
186 				goto done;
187 			}
188 			*outbuf = newbuf;
189 			zb.outbuf = newbuf + *outlen;
190 			zb.outlen = GOT_ZSTREAM_BUFSIZE;
191 		}
192 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
193 
194 done:
195 	got_inflate_end(&zb);
196 	return err;
197 }
198 
199 const struct got_error *
200 got_inflate_to_fd(size_t *outlen, int infd, int outfd)
201 {
202 	const struct got_error *err = NULL;
203 	size_t avail;
204 	struct got_zstream_buf zb;
205 
206 	err = got_inflate_init(&zb, NULL, GOT_ZSTREAM_BUFSIZE);
207 	if (err)
208 		goto done;
209 
210 	*outlen = 0;
211 
212 	do {
213 		err = got_inflate_read_fd(&zb, infd, &avail);
214 		if (err)
215 			return err;
216 		if (avail > 0) {
217 			ssize_t n;
218 			n = write(outfd, zb.outbuf, avail);
219 			if (n != avail) {
220 				err = got_error_from_errno();
221 				goto done;
222 			}
223 			*outlen += avail;
224 		}
225 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
226 
227 done:
228 	if (err == NULL) {
229 		if (lseek(outfd, SEEK_SET, 0) == -1)
230 			err = got_error_from_errno();
231 	}
232 	got_inflate_end(&zb);
233 	return err;
234 }
235 
236 const struct got_error *
237 got_inflate_to_file(size_t *outlen, FILE *infile, FILE *outfile)
238 {
239 	const struct got_error *err;
240 	size_t avail;
241 	struct got_zstream_buf zb;
242 
243 	err = got_inflate_init(&zb, NULL, GOT_ZSTREAM_BUFSIZE);
244 	if (err)
245 		goto done;
246 
247 	*outlen = 0;
248 
249 	do {
250 		err = got_inflate_read(&zb, infile, &avail);
251 		if (err)
252 			return err;
253 		if (avail > 0) {
254 			size_t n;
255 			n = fwrite(zb.outbuf, avail, 1, outfile);
256 			if (n != 1) {
257 				err = got_ferror(outfile, GOT_ERR_IO);
258 				goto done;
259 			}
260 			*outlen += avail;
261 		}
262 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
263 
264 done:
265 	if (err == NULL)
266 		rewind(outfile);
267 	got_inflate_end(&zb);
268 	return err;
269 }