1 | #include <string.h> |
2 | #include <resolv.h> |
3 | #include "libc.h" |
4 | |
5 | |
6 | |
7 | |
8 | static int getoffs(short *offs, const unsigned char *base, const unsigned char *s) |
9 | { |
10 | int i=0; |
11 | for (;;) { |
12 | while (*s & 0xc0) { |
13 | if ((*s & 0xc0) != 0xc0) return 0; |
14 | s = base + ((s[0]&0x3f)<<8 | s[1]); |
15 | } |
16 | if (!*s) return i; |
17 | if (s-base >= 0x4000) return 0; |
18 | offs[i++] = s-base; |
19 | s += *s + 1; |
20 | } |
21 | } |
22 | |
23 | |
24 | static int getlens(unsigned char *lens, const char *s, int l) |
25 | { |
26 | int i=0,j=0,k=0; |
27 | for (;;) { |
28 | for (; j<l && s[j]!='.'; j++); |
29 | if (j-k-1u > 62) return 0; |
30 | lens[i++] = j-k; |
31 | if (j==l) return i; |
32 | k = ++j; |
33 | } |
34 | } |
35 | |
36 | |
37 | static int match(int *offset, const unsigned char *base, const unsigned char *dn, |
38 | const char *end, const unsigned char *lens, int nlen) |
39 | { |
40 | int l, o, m=0; |
41 | short offs[128]; |
42 | int noff = getoffs(offs, base, dn); |
43 | if (!noff) return 0; |
44 | for (;;) { |
45 | l = lens[--nlen]; |
46 | o = offs[--noff]; |
47 | end -= l; |
48 | if (l != base[o] || memcmp(base+o+1, end, l)) |
49 | return m; |
50 | *offset = o; |
51 | m += l; |
52 | if (nlen) m++; |
53 | if (!nlen || !noff) return m; |
54 | end--; |
55 | } |
56 | } |
57 | |
58 | int __dn_comp(const char *src, unsigned char *dst, int space, unsigned char **dnptrs, unsigned char **lastdnptr) |
59 | { |
60 | int i, j, n, m=0, offset, bestlen=0, bestoff; |
61 | unsigned char lens[127]; |
62 | unsigned char **p; |
63 | const char *end; |
64 | size_t l = strnlen(src, 255); |
65 | if (l && src[l-1] == '.') l--; |
| |
66 | if (l>253 || space<=0) return -1; |
| |
| |
| |
67 | if (!l) { |
| |
68 | *dst = 0; |
69 | return 1; |
70 | } |
71 | end = src+l; |
72 | n = getlens(lens, src, l); |
73 | if (!n) return -1; |
| |
74 | |
75 | p = dnptrs; |
76 | if (p && *p) for (p++; *p; p++) { |
| |
| 8 | | Loop condition is true. Entering loop body | |
|
| 13 | | Loop condition is false. Execution continues on line 87 | |
|
77 | m = match(&offset, *dnptrs, *p, end, lens, n); |
78 | if (m > bestlen) { |
| 9 | | Assuming 'm' is > 'bestlen' | |
|
| |
79 | bestlen = m; |
80 | bestoff = offset; |
81 | if (m == l) |
| 11 | | Assuming 'm' is not equal to 'l' | |
|
| |
82 | break; |
83 | } |
84 | } |
85 | |
86 | |
87 | if (space < l-bestlen+2+(bestlen-1 < l-1)) return -1; |
| |
88 | memcpy(dst+1, src, l-bestlen); |
89 | for (i=j=0; i<l-bestlen; i+=lens[j++]+1) |
| 15 | | Loop condition is true. Entering loop body | |
|
| 16 | | Loop condition is true. Entering loop body | |
|
90 | dst[i] = lens[j]; |
| 17 | | Assigned value is garbage or undefined |
|
91 | |
92 | |
93 | if (bestlen) { |
94 | dst[i++] = 0xc0 | bestoff>>8; |
95 | dst[i++] = bestoff; |
96 | } else |
97 | dst[i++] = 0; |
98 | |
99 | |
100 | if (i>2 && lastdnptr && dnptrs && *dnptrs) { |
101 | while (*p) p++; |
102 | if (p+1 < lastdnptr) { |
103 | *p++ = dst; |
104 | *p=0; |
105 | } |
106 | } |
107 | return i; |
108 | } |
109 | |
110 | weak_alias(__dn_comp, dn_comp)extern __typeof(__dn_comp) dn_comp __attribute__((weak, alias ("__dn_comp"))); |