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 #include <sys/stat.h>
19 
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <sha1.h>
24 #include <endian.h>
25 
26 #include "got_error.h"
27 
28 #include "got_fileindex_lib.h"
29 
30 const struct got_error *
31 got_fileindex_entry_open(struct got_fileindex_entry **entry,
32     const char *ondisk_path, const char *relpath, uint8_t *blob_sha1)
33 {
34 	struct stat sb;
35 	size_t len;
36 
37 	if (lstat(ondisk_path, &sb) != 0)
38 		return got_error_from_errno();
39 
40 	*entry = calloc(1, sizeof(**entry));
41 	if (*entry == NULL)
42 		return got_error(GOT_ERR_NO_MEM);
43 
44 	(*entry)->path = strdup(relpath);
45 	if ((*entry)->path == NULL) {
46 		free(*entry);
47 		*entry = NULL;
48 		return got_error(GOT_ERR_NO_MEM);
49 	}
50 	
51 	(*entry)->ctime_sec = sb.st_ctime;
52 	(*entry)->ctime_nsec = sb.st_ctimensec;
53 	(*entry)->mtime_sec = sb.st_mtime;
54 	(*entry)->mtime_nsec = sb.st_mtimensec;
55 	(*entry)->uid = sb.st_uid;
56 	(*entry)->gid = sb.st_gid;
57 	(*entry)->size = (sb.st_size & 0xffffffff);
58 	if (sb.st_mode & S_IFLNK)
59 		(*entry)->mode = GOT_INDEX_ENTRY_MODE_SYMLINK;
60 	else
61 		(*entry)->mode = GOT_INDEX_ENTRY_MODE_REGULAR_FILE;
62 	(*entry)->mode |= ((sb.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO)) <<
63 	    GOT_INDEX_ENTRY_MODE_PERMS_SHIFT);
64 	memcpy((*entry)->blob_sha1, blob_sha1, SHA1_DIGEST_LENGTH);
65 	len = strlen(relpath);
66 	if (len > GOT_INDEX_ENTRY_F_PATH_LEN)
67 		len = GOT_INDEX_ENTRY_F_PATH_LEN;
68 	(*entry)->flags |= len;
69 
70 	return NULL;
71 }
72 
73 void
74 got_fileindex_entry_close(struct got_fileindex_entry *entry)
75 {
76 	free(entry->path);
77 	free(entry);
78 }
79 
80 const struct got_error *
81 got_fileindex_entry_add(struct got_fileindex *fileindex,
82     struct got_fileindex_entry *entry)
83 {
84 	/* TODO keep entries sorted by name */
85 	TAILQ_INSERT_TAIL(&fileindex->entries, entry, entry);
86 	fileindex->nentries++;
87 	return NULL;
88 }
89 
90 struct got_fileindex *
91 got_fileindex_open(void)
92 {
93 	struct got_fileindex *fileindex;
94 
95 	fileindex = calloc(1, sizeof(*fileindex));
96 	if (fileindex)
97 		TAILQ_INIT(&fileindex->entries);
98 	return fileindex;
99 }
100 
101 void
102 got_fileindex_close(struct got_fileindex *fileindex)
103 {
104 	struct got_fileindex_entry *entry;
105 
106 	while (!TAILQ_EMPTY(&fileindex->entries)) {
107 		entry = TAILQ_FIRST(&fileindex->entries);
108 		TAILQ_REMOVE(&fileindex->entries, entry, entry);
109 		got_fileindex_entry_close(entry);
110 		fileindex->nentries--;
111 	}
112 	free(fileindex);
113 }
114 
115 static const struct got_error *
116 write_fileindex_val64(SHA1_CTX *ctx, uint64_t val, FILE *outfile)
117 {
118 	uint8_t buf[sizeof(uint64_t)];
119 	size_t n;
120 
121 	val = htobe64(val);
122 	memcpy(buf, &val, sizeof(val));
123 	SHA1Update(ctx, buf, sizeof(val));
124 	n = fwrite(buf, 1, sizeof(val), outfile);
125 	if (n != sizeof(val))
126 		return got_ferror(outfile, GOT_ERR_IO);
127 	return NULL;
128 }
129 
130 static const struct got_error *
131 write_fileindex_val32(SHA1_CTX *ctx, uint32_t val, FILE *outfile)
132 {
133 	uint8_t buf[sizeof(uint32_t)];
134 	size_t n;
135 
136 	val = htobe32(val);
137 	memcpy(buf, &val, sizeof(val));
138 	SHA1Update(ctx, buf, sizeof(val));
139 	n = fwrite(buf, 1, sizeof(val), outfile);
140 	if (n != sizeof(val))
141 		return got_ferror(outfile, GOT_ERR_IO);
142 	return NULL;
143 }
144 
145 static const struct got_error *
146 write_fileindex_val16(SHA1_CTX *ctx, uint16_t val, FILE *outfile)
147 {
148 	uint8_t buf[sizeof(uint16_t)];
149 	size_t n;
150 
151 	val = htobe16(val);
152 	memcpy(buf, &val, sizeof(val));
153 	SHA1Update(ctx, buf, sizeof(val));
154 	n = fwrite(buf, 1, sizeof(val), outfile);
155 	if (n != sizeof(val))
156 		return got_ferror(outfile, GOT_ERR_IO);
157 	return NULL;
158 }
159 
160 static const struct got_error *
161 write_fileindex_path(SHA1_CTX *ctx, const char *path, FILE *outfile)
162 {
163 	size_t n, len, pad;
164 	static const uint8_t zero[8] = { 0 };
165 
166 	len = strlen(path);
167 	pad = (len % 8);
168 
169 	SHA1Update(ctx, path, len);
170 	n = fwrite(path, 1, len, outfile);
171 	if (n != len)
172 		return got_ferror(outfile, GOT_ERR_IO);
173 	if (pad == 0)
174 		return NULL;
175 	SHA1Update(ctx, zero, pad);
176 	n = fwrite(zero, 1, pad, outfile);
177 	if (n != pad)
178 		return got_ferror(outfile, GOT_ERR_IO);
179 	return NULL;
180 }
181 
182 static const struct got_error *
183 write_fileindex_entry(SHA1_CTX *ctx, struct got_fileindex_entry *entry,
184     FILE *outfile)
185 {
186 	const struct got_error *err;
187 	size_t n;
188 
189 	err = write_fileindex_val64(ctx, entry->ctime_sec, outfile);
190 	if (err)
191 		return err;
192 	err = write_fileindex_val64(ctx, entry->ctime_nsec, outfile);
193 	if (err)
194 		return err;
195 	err = write_fileindex_val64(ctx, entry->mtime_sec, outfile);
196 	if (err)
197 		return err;
198 	err = write_fileindex_val64(ctx, entry->mtime_nsec, outfile);
199 	if (err)
200 		return err;
201 
202 	err = write_fileindex_val32(ctx, entry->uid, outfile);
203 	if (err)
204 		return err;
205 	err = write_fileindex_val32(ctx, entry->gid, outfile);
206 	if (err)
207 		return err;
208 	err = write_fileindex_val32(ctx, entry->size, outfile);
209 	if (err)
210 		return err;
211 
212 	err = write_fileindex_val16(ctx, entry->mode, outfile);
213 	if (err)
214 		return err;
215 
216 	SHA1Update(ctx, entry->blob_sha1, SHA1_DIGEST_LENGTH);
217 	n = fwrite(entry->blob_sha1, 1, SHA1_DIGEST_LENGTH, outfile);
218 	if (n != SHA1_DIGEST_LENGTH)
219 		return got_ferror(outfile, GOT_ERR_IO);
220 
221 	err = write_fileindex_val32(ctx, entry->flags, outfile);
222 	if (err)
223 		return err;
224 
225 	err = write_fileindex_path(ctx, entry->path, outfile);
226 	return err;
227 }
228 
229 const struct got_error *
230 got_fileindex_write(struct got_fileindex *fileindex, FILE *outfile)
231 {
232 	struct got_fileindex_hdr hdr;
233 	struct got_fileindex_entry *entry;
234 	SHA1_CTX ctx;
235 	uint8_t sha1[SHA1_DIGEST_LENGTH];
236 	size_t n;
237 	const size_t len = sizeof(hdr.signature) + sizeof(hdr.version) +
238 	    sizeof(hdr.nentries);
239 	uint8_t buf[len];
240 
241 	SHA1Init(&ctx);
242 
243 	hdr.signature = htobe32(GOT_FILE_INDEX_SIGNATURE);
244 	hdr.version = htobe32(GOT_FILE_INDEX_VERSION);
245 	hdr.nentries = htobe32(fileindex->nentries);
246 
247 	memcpy(buf, &hdr, len);
248 	SHA1Update(&ctx, buf, len);
249 	n = fwrite(buf, 1, len, outfile);
250 	if (n != len)
251 		return got_ferror(outfile, GOT_ERR_IO);
252 
253 	TAILQ_FOREACH(entry, &fileindex->entries, entry) {
254 		const struct got_error *err;
255 		err = write_fileindex_entry(&ctx, entry, outfile);
256 		if (err)
257 			return err;
258 	}
259 
260 	SHA1Final(sha1, &ctx);
261 	n = fwrite(sha1, 1, sizeof(sha1), outfile);
262 	if (n != sizeof(sha1))
263 		return got_ferror(outfile, GOT_ERR_IO);
264 
265 	return NULL;
266 }