Commit | Line | Data |
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0049c6b5 MW |
1 | #include "lib.h" |
2 | ||
3 | static int status = 0; | |
4 | static unsigned flags = 0; | |
5 | #define F_FIX 1u | |
6 | ||
7 | static void vgripe_syserr(int st, int err, const char *fmt, va_list ap) | |
8 | { vmoan_syserr(err, fmt, ap); if (st > status) status = st; } | |
9 | static void vgripe(int st, const char *fmt, va_list ap) | |
10 | { vgripe_syserr(st, 0, fmt, ap); } | |
11 | PRINTF_LIKE(3, 4) | |
12 | static void gripe_syserr(int st, int err, const char *fmt, ...) | |
13 | { | |
14 | va_list ap; | |
15 | va_start(ap, fmt); vgripe_syserr(st, err, fmt, ap); va_end(ap); | |
16 | } | |
17 | PRINTF_LIKE(2, 3) static void gripe(int st, const char *fmt, ...) | |
18 | { va_list ap; va_start(ap, fmt); vgripe(st, fmt, ap); va_end(ap); } | |
19 | ||
20 | static int carefully_read(int fd, off_t off, | |
21 | void *p, size_t sz, const char *file) | |
22 | { | |
23 | ssize_t n; | |
24 | char *q = p; | |
25 | ||
26 | if (lseek(fd, off, SEEK_SET) < 0) | |
27 | { gripe_syserr(2, errno, "failed to seek in `%s'", file); return (-1); } | |
28 | ||
29 | while (sz) { | |
30 | n = read(fd, q, sz); | |
31 | if (n < 0) | |
32 | { gripe_syserr(2, errno, "failed to read `%s'", file); return (-1); } | |
33 | else if (!n) | |
34 | { gripe(2, "unexpected end-of-file reading `%s'", file); return (-1); } | |
35 | q += n; sz -= n; | |
36 | } | |
37 | return (0); | |
38 | } | |
39 | ||
40 | typedef uint_least32_t u32; | |
41 | #define Pu32 PRIuLEAST32 | |
42 | ||
43 | static u32 load32(const unsigned char *p) | |
44 | { | |
45 | return (((u32)p[0] << 0) | ((u32)p[1] << 8) | | |
46 | ((u32)p[2] << 16) | ((u32)p[3] << 24)); | |
47 | } | |
48 | ||
49 | #define CAHF_GRIPE 1u | |
50 | #define CAHF_FULL 1u | |
51 | static int check_anchor_header(const unsigned char *b, secaddr addr, | |
52 | unsigned f, const char *file) | |
53 | { | |
54 | unsigned i, t; | |
55 | secaddr n; | |
56 | ||
57 | if (b[0] != 2) { | |
58 | if (f&CAHF_GRIPE) | |
59 | gripe(1, "anchor descriptor not found at `%s' sector %"PRIuSEC"", | |
60 | file, addr); | |
61 | return (-1); | |
62 | } | |
63 | ||
64 | for (i = 0, t = 0; i < 16; i++) if (i != 4) t += b[i]; | |
65 | t %= 256; | |
66 | if (b[4] != t) { | |
67 | if (f&CAHF_GRIPE) | |
68 | gripe(1, "bad anchor descriptor header checksum (%u /= %u) " | |
69 | "at `%s' sector %"PRIuSEC"", (unsigned)b[4], t, file, addr); | |
70 | return (-1); | |
71 | } | |
72 | ||
73 | if (f&CAHF_FULL) { | |
74 | n = load32(b + 12); | |
75 | if (n != addr) { | |
76 | if (f&CAHF_GRIPE) | |
77 | gripe(1, "bad sector number in anchor descriptor " | |
78 | "(%"PRIuSEC" /= %"PRIuSEC") in `%s'", | |
79 | n, addr, file); | |
80 | return (-1); | |
81 | } | |
82 | } | |
83 | ||
84 | return (0); | |
85 | } | |
86 | ||
87 | static int all_zero_p(const unsigned char *p, size_t sz) | |
88 | { | |
89 | while (sz) { | |
90 | if (*p) return (0); | |
91 | p++; sz--; | |
92 | } | |
93 | return (1); | |
94 | } | |
95 | ||
96 | static void check_img(const char *file) | |
97 | { | |
98 | int fd = -1; | |
0049c6b5 | 99 | unsigned char b[SECTORSZ], bb[SECTORSZ]; |
eac2ed1a MW |
100 | off_t volsz; |
101 | int blksz; | |
0049c6b5 MW |
102 | secaddr end; |
103 | unsigned i, j; | |
104 | ||
fb48dc9c | 105 | open_dvd(file, (flags&F_FIX) ? O_RDWR : O_RDONLY, &fd, 0); |
eac2ed1a MW |
106 | blksz = SECTORSZ; volsz = device_size(fd, file, &blksz); |
107 | if (SECTORSZ != 2048) | |
108 | { gripe(2, "device sector size %d /= 2048", blksz); goto end; } | |
109 | if (volsz%SECTORSZ) { | |
0049c6b5 MW |
110 | gripe(2, "bad length for `%s' -- not whole number of sectors", file); |
111 | goto end; | |
112 | } | |
eac2ed1a | 113 | end = volsz/SECTORSZ; |
0049c6b5 MW |
114 | |
115 | if (carefully_read(fd, 256*SECTORSZ, b, SECTORSZ, file) || | |
116 | check_anchor_header(b, 256, CAHF_GRIPE | CAHF_FULL, file)) | |
117 | goto end; | |
118 | ||
119 | for (i = 1; i < 32768; i++) { | |
120 | if (carefully_read(fd, (off_t)(end - i)*SECTORSZ, bb, SECTORSZ, file)) | |
121 | goto end; | |
122 | if (bb[0] || !all_zero_p(bb, SECTORSZ)) goto nonzero; | |
123 | } | |
124 | gripe(1, "too many trailing zero sectors: " | |
323c8d53 | 125 | "couldn't find backup anchor descriptor in `%s'", file); |
0049c6b5 MW |
126 | goto end; |
127 | nonzero: | |
128 | j = i; | |
129 | for (;;) { | |
130 | if (bb[0] == 2 && !check_anchor_header(bb, end - j, 0, file)) | |
131 | break; | |
132 | j++; | |
133 | if (j > i + 256) { | |
134 | gripe(1, "failed to find backup anchor descriptor in `%s'", file); | |
135 | goto end; | |
136 | } | |
137 | if (carefully_read(fd, (off_t)(end - j)*SECTORSZ, bb, SECTORSZ, file)) | |
138 | goto end; | |
139 | } | |
140 | if (j > i) { | |
141 | gripe(1, "found backup anchor descriptor at sector %"PRIuSEC" " | |
142 | " = %"PRIuSEC" from end, = %"PRIuSEC" from trailing zeros", | |
143 | end - j, j, j - i + 1); | |
144 | i = j; | |
145 | } | |
146 | ||
147 | if (check_anchor_header(bb, end - i, CAHF_GRIPE | CAHF_FULL, file)) | |
148 | goto end; | |
149 | ||
150 | if (MEMCMP(b + 16, != , bb + 16, SECTORSZ - 16)) { | |
151 | gripe(1, "backup anchor descriptor in sector %"PRIuSEC" " | |
152 | "doesn't match primary in sector 256 of `%s'", | |
153 | end - i, file); | |
154 | goto end; | |
155 | } | |
156 | ||
157 | if (i > 1) { | |
158 | if (!(flags&F_FIX)) | |
159 | gripe(1, "%u trailing zero sectors in `%s'", i - 1, file); | |
160 | else { | |
161 | if (ftruncate(fd, (off_t)(end - i + 1)*SECTORSZ)) | |
162 | gripe_syserr(2, errno, | |
163 | "failed to truncate `%s' to %"PRIuSEC" sectors", | |
164 | file, end - i + 1); | |
165 | else | |
166 | moan("removed %u trailing zero sectors from `%s'", i - 1, file); | |
167 | } | |
168 | } | |
169 | ||
170 | end: | |
171 | if (fd != -1) close(fd); | |
172 | } | |
173 | ||
174 | static void usage(FILE *fp) | |
175 | { fprintf(fp, "usage: %s [-x] IMG ...\n", prog); } | |
176 | ||
177 | int main(int argc, char *argv[]) | |
178 | { | |
179 | int i, opt; | |
180 | unsigned f = 0; | |
181 | #define f_bogus 1u | |
182 | ||
183 | set_prog(argv[0]); | |
184 | for (;;) { | |
185 | opt = getopt(argc, argv, "hx"); if (opt < 0) break; | |
186 | switch (opt) { | |
187 | case 'h': usage(stdout); exit(0); | |
188 | case 'x': flags |= F_FIX; break; | |
189 | default: f |= f_bogus; break; | |
190 | } | |
191 | } | |
192 | if (optind >= argc) f |= f_bogus; | |
193 | if (f&f_bogus) { usage(stderr); exit(2); } | |
fb48dc9c MW |
194 | setlocale(LC_ALL, ""); |
195 | progress_init(&progress); | |
0049c6b5 | 196 | for (i = optind; i < argc; i++) check_img(argv[i]); |
fb48dc9c | 197 | progress_free(&progress); |
0049c6b5 MW |
198 | return (status); |
199 | } |