1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/* $OpenBSD: ksyms.c,v 1.8 2015/02/07 03:26:20 tedu Exp $ */
/*
* Copyright (c) 2008 Miodrag Vallat.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <sys/exec.h>
#include <elf_abi.h>
#include "hangman.h"
static int ksyms_elf_parse(void);
void
sym_getword()
{
uint tries;
off_t pos;
int buflen;
char symbuf[1 + BUFSIZ], *sym, *end;
size_t symlen;
for (tries = 0; tries < MAXBADWORDS; tries++) {
pos = arc4random_uniform(symsize);
if (lseek(symfd, pos + symoffs, SEEK_SET) == -1)
continue;
buflen = read(symfd, symbuf, BUFSIZ);
if (buflen < 0)
continue;
/*
* The buffer is hopefully large enough to hold at least
* a complete symbol, i.e. two occurences of NUL, or
* one occurence of NUL and the buffer containing the end
* of the string table. We make sure the buffer will be
* NUL terminated in all cases.
*/
if (buflen + pos >= symsize)
buflen = symsize - pos;
*(end = symbuf + buflen) = '\0';
for (sym = symbuf; *sym != '\0'; sym++)
;
if (sym == end)
continue;
symlen = strlen(++sym);
if (symlen < MINLEN || symlen > MAXLEN)
continue;
/* ignore symbols containing dots or dollar signs */
if (strchr(sym, '.') != NULL || strchr(sym, '$') != NULL)
continue;
break;
}
if (tries >= MAXBADWORDS) {
mvcur(0, COLS - 1, LINES -1, 0);
endwin();
errx(1, "can't seem a suitable symbol in %s",
Dict_name);
}
strlcpy(Word, sym, sizeof Word);
strlcpy(Known, sym, sizeof Known);
for (sym = Known; *sym != '\0'; sym++) {
if (*sym == '-')
*sym = '_'; /* try not to confuse player */
if (isalnum((unsigned char)*sym))
*sym = '-';
}
}
int
sym_setup()
{
if ((symfd = open(Dict_name, O_RDONLY)) < 0)
return -1;
if (ksyms_elf_parse() == 0)
return 0;
close(symfd);
errno = ENOEXEC;
return -1;
}
int
ksyms_elf_parse()
{
Elf_Ehdr eh;
Elf_Shdr sh;
uint s;
if (lseek(symfd, 0, SEEK_SET) == -1)
return -1;
if (read(symfd, &eh, sizeof eh) != sizeof eh)
return -1;
if (!IS_ELF(eh))
return -1;
if (lseek(symfd, eh.e_shoff, SEEK_SET) == -1)
return -1;
symoffs = 0;
symsize = 0;
for (s = 0; s < eh.e_shnum; s++) {
if (read(symfd, &sh, sizeof sh) != sizeof sh)
return -1;
/*
* There should be two string table sections, one with the
* name of the sections themselves, and one with the symbol
* names. Just pick the largest one.
*/
if (sh.sh_type == SHT_STRTAB) {
if (symsize > (off_t)sh.sh_size)
continue;
symoffs = (off_t)sh.sh_offset;
symsize = (off_t)sh.sh_size;
}
}
if (symsize == 0)
return -1;
return 0;
}
|
