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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
|
/* $OpenBSD: buffer.c,v 1.39 2008/03/24 16:11:02 deraadt Exp $ */
/*
* Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
*
* 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 <sys/types.h>
#include <sys/uio.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "bgpd.h"
void buf_enqueue(struct msgbuf *, struct buf *);
void buf_dequeue(struct msgbuf *, struct buf *);
struct buf *
buf_open(size_t len)
{
struct buf *buf;
if ((buf = calloc(1, sizeof(struct buf))) == NULL)
return (NULL);
if ((buf->buf = malloc(len)) == NULL) {
free(buf);
return (NULL);
}
buf->size = len;
buf->fd = -1;
return (buf);
}
struct buf *
buf_grow(struct buf *buf, size_t len)
{
void *p;
if ((p = realloc(buf->buf, buf->size + len)) == NULL) {
free(buf->buf);
buf->buf = NULL;
buf->size = 0;
return (NULL);
}
buf->buf = p;
buf->size += len;
return (buf);
}
int
buf_add(struct buf *buf, const void *data, size_t len)
{
if (buf->wpos + len > buf->size)
return (-1);
memcpy(buf->buf + buf->wpos, data, len);
buf->wpos += len;
return (0);
}
void *
buf_reserve(struct buf *buf, size_t len)
{
void *b;
if (buf->wpos + len > buf->size)
return (NULL);
b = buf->buf + buf->wpos;
buf->wpos += len;
return (b);
}
int
buf_close(struct msgbuf *msgbuf, struct buf *buf)
{
buf_enqueue(msgbuf, buf);
return (1);
}
int
buf_write(int sock, struct buf *buf)
{
ssize_t n;
if ((n = write(sock, buf->buf + buf->rpos,
buf->size - buf->rpos)) == -1) {
if (errno == EAGAIN || errno == ENOBUFS ||
errno == EINTR) /* try later */
return (0);
else
return (-1);
}
if (n == 0) { /* connection closed */
errno = 0;
return (-2);
}
if (buf->rpos + n < buf->size) { /* not all data written yet */
buf->rpos += n;
return (0);
} else
return (1);
}
void
buf_free(struct buf *buf)
{
free(buf->buf);
free(buf);
}
void
msgbuf_init(struct msgbuf *msgbuf)
{
msgbuf->queued = 0;
msgbuf->fd = -1;
TAILQ_INIT(&msgbuf->bufs);
}
void
msgbuf_clear(struct msgbuf *msgbuf)
{
struct buf *buf;
while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL)
buf_dequeue(msgbuf, buf);
}
int
msgbuf_write(struct msgbuf *msgbuf)
{
struct iovec iov[IOV_MAX];
struct buf *buf, *next;
int i = 0;
ssize_t n;
struct msghdr msg;
struct cmsghdr *cmsg;
union {
struct cmsghdr hdr;
char buf[CMSG_SPACE(sizeof(int))];
} cmsgbuf;
bzero(&iov, sizeof(iov));
bzero(&msg, sizeof(msg));
TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
if (i >= IOV_MAX)
break;
iov[i].iov_base = buf->buf + buf->rpos;
iov[i].iov_len = buf->size - buf->rpos;
i++;
if (buf->fd != -1)
break;
}
msg.msg_iov = iov;
msg.msg_iovlen = i;
if (buf != NULL && buf->fd != -1) {
msg.msg_control = (caddr_t)&cmsgbuf.buf;
msg.msg_controllen = sizeof(cmsgbuf.buf);
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
*(int *)CMSG_DATA(cmsg) = buf->fd;
}
if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) {
if (errno == EAGAIN || errno == ENOBUFS ||
errno == EINTR) /* try later */
return (0);
else
return (-1);
}
if (n == 0) { /* connection closed */
errno = 0;
return (-2);
}
/*
* assumption: fd got sent if sendmsg sent anything
* this works because fds are passed one at a time
*/
if (buf != NULL && buf->fd != -1) {
close(buf->fd);
buf->fd = -1;
}
for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
buf = next) {
next = TAILQ_NEXT(buf, entry);
if (buf->rpos + n >= buf->size) {
n -= buf->size - buf->rpos;
buf_dequeue(msgbuf, buf);
} else {
buf->rpos += n;
n = 0;
}
}
return (0);
}
void
buf_enqueue(struct msgbuf *msgbuf, struct buf *buf)
{
TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry);
msgbuf->queued++;
}
void
buf_dequeue(struct msgbuf *msgbuf, struct buf *buf)
{
TAILQ_REMOVE(&msgbuf->bufs, buf, entry);
if (buf->fd != -1)
close(buf->fd);
msgbuf->queued--;
buf_free(buf);
}
|
