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
|
/* -*- mode: c; c-file-style: "openbsd" -*- */
#include "lldpd.h"
#include <sys/param.h>
#include <sys/uio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/* Stolen from sbin/pflogd/privsep.c from OpenBSD */
/*
* Copyright (c) 2003 Can Erkin Acar
* Copyright (c) 2003 Anil Madhavapeddy <anil@recoil.org>
*
* Permission to use, copy, modify, and/or 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.
*/
/* Read all data or return 1 for error. */
int
may_read(enum priv_context ctx, void *buf, size_t n)
{
char *s = buf;
ssize_t res, pos = 0;
while (n > pos) {
res = read(priv_fd(ctx), s + pos, n - pos);
switch (res) {
case -1:
if (errno == EINTR || errno == EAGAIN) continue;
return 1;
case 0:
return 1;
default:
pos += res;
}
}
return (0);
}
/* Read data with the assertion that it all must come through, or
* else abort the process. Based on atomicio() from openssh. */
void
must_read(enum priv_context ctx, void *buf, size_t n)
{
char *s = buf;
ssize_t res, pos = 0;
while (n > pos) {
res = read(priv_fd(ctx), s + pos, n - pos);
switch (res) {
case -1:
if (errno == EINTR || errno == EAGAIN) continue;
_exit(0);
case 0:
_exit(0);
default:
pos += res;
}
}
}
/* Write data with the assertion that it all has to be written, or
* else abort the process. Based on atomicio() from openssh. */
void
must_write(enum priv_context ctx, const void *buf, size_t n)
{
const char *s = buf;
ssize_t res, pos = 0;
while (n > pos) {
res = write(priv_fd(ctx), s + pos, n - pos);
switch (res) {
case -1:
if (errno == EINTR || errno == EAGAIN) continue;
_exit(0);
case 0:
_exit(0);
default:
pos += res;
}
}
}
|
