1 /* $OpenBSD: imsg-buffer.c,v 1.18 2023/12/12 15:47:41 claudio Exp $ */
4 * Copyright (c) 2023 Claudio Jeker <claudio@openbsd.org>
5 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 #include <sys/types.h>
21 #include <sys/socket.h>
23 #include <arpa/inet.h>
32 #include "got_compat.h"
35 static int ibuf_realloc(struct ibuf *, size_t);
36 static void ibuf_enqueue(struct msgbuf *, struct ibuf *);
37 static void ibuf_dequeue(struct msgbuf *, struct ibuf *);
38 static void msgbuf_drain(struct msgbuf *, size_t);
49 if ((buf = calloc(1, sizeof(struct ibuf))) == NULL)
51 if ((buf->buf = calloc(len, 1)) == NULL) {
55 buf->size = buf->max = len;
62 ibuf_dynamic(size_t len, size_t max)
66 if (max == 0 || max < len) {
71 if ((buf = calloc(1, sizeof(struct ibuf))) == NULL)
74 if ((buf->buf = calloc(len, 1)) == NULL) {
87 ibuf_realloc(struct ibuf *buf, size_t len)
91 /* on static buffers max is eq size and so the following fails */
92 if (len > SIZE_MAX - buf->wpos || buf->wpos + len > buf->max) {
97 b = recallocarray(buf->buf, buf->size, buf->wpos + len, 1);
101 buf->size = buf->wpos + len;
107 ibuf_reserve(struct ibuf *buf, size_t len)
111 if (len > SIZE_MAX - buf->wpos || buf->max == 0) {
116 if (buf->wpos + len > buf->size)
117 if (ibuf_realloc(buf, len) == -1)
120 b = buf->buf + buf->wpos;
126 ibuf_add(struct ibuf *buf, const void *data, size_t len)
130 if ((b = ibuf_reserve(buf, len)) == NULL)
133 memcpy(b, data, len);
138 ibuf_add_ibuf(struct ibuf *buf, const struct ibuf *from)
140 return ibuf_add(buf, ibuf_data(from), ibuf_size(from));
143 /* remove after tree is converted */
145 ibuf_add_buf(struct ibuf *buf, const struct ibuf *from)
147 return ibuf_add_ibuf(buf, from);
151 ibuf_add_n8(struct ibuf *buf, uint64_t value)
155 if (value > UINT8_MAX) {
160 return ibuf_add(buf, &v, sizeof(v));
164 ibuf_add_n16(struct ibuf *buf, uint64_t value)
168 if (value > UINT16_MAX) {
173 return ibuf_add(buf, &v, sizeof(v));
177 ibuf_add_n32(struct ibuf *buf, uint64_t value)
181 if (value > UINT32_MAX) {
186 return ibuf_add(buf, &v, sizeof(v));
190 ibuf_add_n64(struct ibuf *buf, uint64_t value)
192 value = htobe64(value);
193 return ibuf_add(buf, &value, sizeof(value));
197 ibuf_add_h16(struct ibuf *buf, uint64_t value)
201 if (value > UINT16_MAX) {
206 return ibuf_add(buf, &v, sizeof(v));
210 ibuf_add_h32(struct ibuf *buf, uint64_t value)
214 if (value > UINT32_MAX) {
219 return ibuf_add(buf, &v, sizeof(v));
223 ibuf_add_h64(struct ibuf *buf, uint64_t value)
225 return ibuf_add(buf, &value, sizeof(value));
229 ibuf_add_zero(struct ibuf *buf, size_t len)
233 if ((b = ibuf_reserve(buf, len)) == NULL)
240 ibuf_seek(struct ibuf *buf, size_t pos, size_t len)
242 /* only allow seeking between rpos and wpos */
243 if (ibuf_size(buf) < pos || SIZE_MAX - pos < len ||
244 ibuf_size(buf) < pos + len) {
249 return (buf->buf + buf->rpos + pos);
253 ibuf_set(struct ibuf *buf, size_t pos, const void *data, size_t len)
257 if ((b = ibuf_seek(buf, pos, len)) == NULL)
260 memcpy(b, data, len);
265 ibuf_set_n8(struct ibuf *buf, size_t pos, uint64_t value)
269 if (value > UINT8_MAX) {
274 return (ibuf_set(buf, pos, &v, sizeof(v)));
278 ibuf_set_n16(struct ibuf *buf, size_t pos, uint64_t value)
282 if (value > UINT16_MAX) {
287 return (ibuf_set(buf, pos, &v, sizeof(v)));
291 ibuf_set_n32(struct ibuf *buf, size_t pos, uint64_t value)
295 if (value > UINT32_MAX) {
300 return (ibuf_set(buf, pos, &v, sizeof(v)));
304 ibuf_set_n64(struct ibuf *buf, size_t pos, uint64_t value)
306 value = htobe64(value);
307 return (ibuf_set(buf, pos, &value, sizeof(value)));
311 ibuf_set_h16(struct ibuf *buf, size_t pos, uint64_t value)
315 if (value > UINT16_MAX) {
320 return (ibuf_set(buf, pos, &v, sizeof(v)));
324 ibuf_set_h32(struct ibuf *buf, size_t pos, uint64_t value)
328 if (value > UINT32_MAX) {
333 return (ibuf_set(buf, pos, &v, sizeof(v)));
337 ibuf_set_h64(struct ibuf *buf, size_t pos, uint64_t value)
339 return (ibuf_set(buf, pos, &value, sizeof(value)));
343 ibuf_data(const struct ibuf *buf)
345 return (buf->buf + buf->rpos);
349 ibuf_size(const struct ibuf *buf)
351 return (buf->wpos - buf->rpos);
355 ibuf_left(const struct ibuf *buf)
359 return (buf->max - buf->wpos);
363 ibuf_truncate(struct ibuf *buf, size_t len)
365 if (ibuf_size(buf) >= len) {
366 buf->wpos = buf->rpos + len;
370 /* only allow to truncate down */
374 return ibuf_add_zero(buf, len - ibuf_size(buf));
378 ibuf_rewind(struct ibuf *buf)
384 ibuf_close(struct msgbuf *msgbuf, struct ibuf *buf)
386 ibuf_enqueue(msgbuf, buf);
390 ibuf_from_buffer(struct ibuf *buf, void *data, size_t len)
392 memset(buf, 0, sizeof(*buf));
394 buf->size = buf->wpos = len;
399 ibuf_from_ibuf(struct ibuf *buf, const struct ibuf *from)
401 ibuf_from_buffer(buf, ibuf_data(from), ibuf_size(from));
405 ibuf_get(struct ibuf *buf, void *data, size_t len)
407 if (ibuf_size(buf) < len) {
412 memcpy(data, ibuf_data(buf), len);
418 ibuf_get_ibuf(struct ibuf *buf, size_t len, struct ibuf *new)
420 if (ibuf_size(buf) < len) {
425 ibuf_from_buffer(new, ibuf_data(buf), len);
431 ibuf_get_n8(struct ibuf *buf, uint8_t *value)
433 return ibuf_get(buf, value, sizeof(*value));
437 ibuf_get_n16(struct ibuf *buf, uint16_t *value)
441 rv = ibuf_get(buf, value, sizeof(*value));
442 *value = be16toh(*value);
447 ibuf_get_n32(struct ibuf *buf, uint32_t *value)
451 rv = ibuf_get(buf, value, sizeof(*value));
452 *value = be32toh(*value);
457 ibuf_get_n64(struct ibuf *buf, uint64_t *value)
461 rv = ibuf_get(buf, value, sizeof(*value));
462 *value = be64toh(*value);
467 ibuf_get_h16(struct ibuf *buf, uint16_t *value)
469 return ibuf_get(buf, value, sizeof(*value));
473 ibuf_get_h32(struct ibuf *buf, uint32_t *value)
475 return ibuf_get(buf, value, sizeof(*value));
479 ibuf_get_h64(struct ibuf *buf, uint64_t *value)
481 return ibuf_get(buf, value, sizeof(*value));
485 ibuf_skip(struct ibuf *buf, size_t len)
487 if (ibuf_size(buf) < len) {
497 ibuf_free(struct ibuf *buf)
501 if (buf->max == 0) /* if buf lives on the stack */
502 abort(); /* abort before causing more harm */
505 freezero(buf->buf, buf->size);
510 ibuf_fd_avail(struct ibuf *buf)
512 return (buf->fd != -1);
516 ibuf_fd_get(struct ibuf *buf)
526 ibuf_fd_set(struct ibuf *buf, int fd)
528 if (buf->max == 0) /* if buf lives on the stack */
529 abort(); /* abort before causing more harm */
536 ibuf_write(struct msgbuf *msgbuf)
538 struct iovec iov[IOV_MAX];
543 memset(&iov, 0, sizeof(iov));
544 TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
547 iov[i].iov_base = ibuf_data(buf);
548 iov[i].iov_len = ibuf_size(buf);
553 if ((n = writev(msgbuf->fd, iov, i)) == -1) {
556 if (errno == ENOBUFS)
561 if (n == 0) { /* connection closed */
566 msgbuf_drain(msgbuf, n);
572 msgbuf_init(struct msgbuf *msgbuf)
576 TAILQ_INIT(&msgbuf->bufs);
580 msgbuf_drain(struct msgbuf *msgbuf, size_t n)
582 struct ibuf *buf, *next;
584 for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
586 next = TAILQ_NEXT(buf, entry);
587 if (n >= ibuf_size(buf)) {
589 ibuf_dequeue(msgbuf, buf);
598 msgbuf_clear(struct msgbuf *msgbuf)
602 while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL)
603 ibuf_dequeue(msgbuf, buf);
607 msgbuf_write(struct msgbuf *msgbuf)
609 struct iovec iov[IOV_MAX];
610 struct ibuf *buf, *buf0 = NULL;
614 struct cmsghdr *cmsg;
617 char buf[CMSG_SPACE(sizeof(int))];
620 memset(&iov, 0, sizeof(iov));
621 memset(&msg, 0, sizeof(msg));
622 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
623 TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
626 if (i > 0 && buf->fd != -1)
628 iov[i].iov_base = ibuf_data(buf);
629 iov[i].iov_len = ibuf_size(buf);
639 msg.msg_control = (caddr_t)&cmsgbuf.buf;
640 msg.msg_controllen = sizeof(cmsgbuf.buf);
641 cmsg = CMSG_FIRSTHDR(&msg);
642 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
643 cmsg->cmsg_level = SOL_SOCKET;
644 cmsg->cmsg_type = SCM_RIGHTS;
645 *(int *)CMSG_DATA(cmsg) = buf0->fd;
649 if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) {
652 if (errno == ENOBUFS)
657 if (n == 0) { /* connection closed */
663 * assumption: fd got sent if sendmsg sent anything
664 * this works because fds are passed one at a time
671 msgbuf_drain(msgbuf, n);
677 msgbuf_queuelen(struct msgbuf *msgbuf)
679 return (msgbuf->queued);
683 ibuf_enqueue(struct msgbuf *msgbuf, struct ibuf *buf)
685 if (buf->max == 0) /* if buf lives on the stack */
686 abort(); /* abort before causing more harm */
687 TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry);
692 ibuf_dequeue(struct msgbuf *msgbuf, struct ibuf *buf)
694 TAILQ_REMOVE(&msgbuf->bufs, buf, entry);