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 "path.h"
29 #include "zb.h"
30 
31 const struct got_error *
32 got_inflate_init(struct got_zstream_buf *zb, 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(GOT_ERR_NO_MEM);
50 		goto done;
51 	}
52 
53 	zb->outbuf = calloc(1, zb->outlen);
54 	if (zb->outbuf == NULL) {
55 		err = got_error(GOT_ERR_NO_MEM);
56 		goto done;
57 	}
58 
59 done:
60 	if (err)
61 		got_inflate_end(zb);
62 	return err;
63 }
64 
65 const struct got_error *
66 got_inflate_read(struct got_zstream_buf *zb, FILE *f, size_t *inlenp,
67     size_t *outlenp)
68 {
69 	size_t last_total_out = zb->z.total_out;
70 	z_stream *z = &zb->z;
71 	int ret;
72 
73 	z->next_out = zb->outbuf;
74 	z->avail_out = zb->outlen;
75 
76 	*outlenp = 0;
77 	if (inlenp)
78 		*inlenp = 0;
79 	do {
80 		if (z->avail_in == 0) {
81 			size_t n = fread(zb->inbuf, 1, zb->inlen, f);
82 			if (n == 0) {
83 				if (ferror(f))
84 					return got_ferror(f, GOT_ERR_IO);
85 				break; /* EOF */
86 			}
87 			z->next_in = zb->inbuf;
88 			z->avail_in = n;
89 			if (inlenp)
90 				*inlenp += n;
91 		}
92 		ret = inflate(z, Z_SYNC_FLUSH);
93 	} while (ret == Z_OK && z->avail_out > 0);
94 
95 	if (ret != Z_OK) {
96 		if (ret != Z_STREAM_END)
97 			return got_error(GOT_ERR_DECOMPRESSION);
98 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
99 	}
100 
101 	*outlenp = z->total_out - last_total_out;
102 	return NULL;
103 }
104 
105 void
106 got_inflate_end(struct got_zstream_buf *zb)
107 {
108 	free(zb->inbuf);
109 	free(zb->outbuf);
110 	inflateEnd(&zb->z);
111 }
112 
113 const struct got_error *
114 got_inflate_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f, size_t insize)
115 {
116 	const struct got_error *err;
117 	size_t inbytes, consumed, avail;
118 	struct got_zstream_buf zb;
119 	void *newbuf;
120 
121 	err = got_inflate_init(&zb, 8192);
122 	if (err)
123 		return err;
124 
125 	*outbuf = NULL;
126 	*outlen = 0;
127 	inbytes = 0;
128 
129 	do {
130 		err = got_inflate_read(&zb, f, &consumed, &avail);
131 		if (err)
132 			return err;
133 		inbytes += consumed;
134 		if (avail == 0) {
135 			if (inbytes < insize)
136 				err = got_error(GOT_ERR_BAD_DELTA);
137 			break;
138 		}
139 		newbuf = reallocarray(*outbuf, 1, *outlen + avail);
140 		if (newbuf == NULL) {
141 			free(*outbuf);
142 			*outbuf = NULL;
143 			*outlen = 0;
144 			err = got_error(GOT_ERR_NO_MEM);
145 			goto done;
146 		}
147 		memcpy(newbuf + *outlen, zb.outbuf, avail);
148 		*outbuf = newbuf;
149 		*outlen += avail;
150 	} while (inbytes < insize);
151 
152 done:
153 	got_inflate_end(&zb);
154 	return err;
155 }
156 
157 const struct got_error *
158 got_inflate_to_tempfile(FILE **outfile, size_t *outlen, FILE *f)
159 {
160 	const struct got_error *err;
161 	size_t avail;
162 	struct got_zstream_buf zb;
163 	void *newbuf;
164 
165 	*outfile = got_opentemp();
166 	if (*outfile == NULL)
167 		return got_error_from_errno();
168 
169 	err = got_inflate_init(&zb, 8192);
170 	if (err)
171 		goto done;
172 
173 	*outlen = 0;
174 
175 	do {
176 		err = got_inflate_read(&zb, f, NULL, &avail);
177 		if (err)
178 			return err;
179 		if (avail > 0) {
180 			size_t n;
181 			n = fwrite(zb.outbuf, avail, 1, *outfile);
182 			if (n != 1) {
183 				err = got_ferror(*outfile, GOT_ERR_IO);
184 				goto done;
185 			}
186 			*outlen += avail;
187 		}
188 	} while (avail > 0);
189 
190 done:
191 	if (err) {
192 		fclose(*outfile);
193 		*outfile = NULL;
194 	} else
195 		rewind(*outfile);
196 	got_inflate_end(&zb);
197 	return err;
198 }