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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:53:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:53:30 +0000
commit2c7cac91ed6e7db0f6937923d2b57f97dbdbc337 (patch)
treec05dc0f8e6aa3accc84e3e5cffc933ed94941383 /lib/imsg.c
parentInitial commit. (diff)
downloadfrr-2536d89cfd3a79f991a2c9774117e8ccbf7cb5df.tar.xz
frr-2536d89cfd3a79f991a2c9774117e8ccbf7cb5df.zip
Adding upstream version 8.4.4.upstream/8.4.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/imsg.c')
-rw-r--r--lib/imsg.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/lib/imsg.c b/lib/imsg.c
new file mode 100644
index 0000000..b46d5cb
--- /dev/null
+++ b/lib/imsg.c
@@ -0,0 +1,327 @@
+/* $OpenBSD$ */
+
+/*
+ * 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 <zebra.h>
+
+#include "memory.h"
+#include "queue.h"
+#include "imsg.h"
+
+static int imsg_fd_overhead = 0;
+
+static int imsg_get_fd(struct imsgbuf *);
+
+#ifndef __OpenBSD__
+/*
+ * The original code calls getdtablecount() which is OpenBSD specific. Use
+ * available_fds() from OpenSMTPD instead.
+ */
+static int available_fds(unsigned int n)
+{
+ unsigned int i;
+ int ret, fds[256];
+
+ if (n > (unsigned int)array_size(fds))
+ return 1;
+
+ ret = 0;
+ for (i = 0; i < n; i++) {
+ fds[i] = -1;
+ if ((fds[i] = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ if (errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT)
+ fds[i] = socket(AF_INET6, SOCK_DGRAM, 0);
+ if (fds[i] < 0) {
+ ret = 1;
+ break;
+ }
+ }
+ }
+
+ for (i = 0; i < n && fds[i] >= 0; i++)
+ close(fds[i]);
+
+ return (ret);
+}
+#endif
+
+void imsg_init(struct imsgbuf *ibuf, int fd)
+{
+ msgbuf_init(&ibuf->w);
+ memset(&ibuf->r, 0, sizeof(ibuf->r));
+ ibuf->fd = fd;
+ ibuf->w.fd = fd;
+ ibuf->pid = getpid();
+ TAILQ_INIT(&ibuf->fds);
+}
+
+ssize_t imsg_read(struct imsgbuf *ibuf)
+{
+ struct msghdr msg;
+ struct cmsghdr *cmsg;
+ union {
+ struct cmsghdr hdr;
+ char buf[CMSG_SPACE(sizeof(int) * 1)];
+ } cmsgbuf;
+ struct iovec iov;
+ ssize_t n;
+ int fd;
+ struct imsg_fd *ifd;
+
+ memset(&msg, 0, sizeof(msg));
+ memset(&cmsgbuf, 0, sizeof(cmsgbuf));
+
+ iov.iov_base = ibuf->r.buf + ibuf->r.wpos;
+ iov.iov_len = sizeof(ibuf->r.buf) - ibuf->r.wpos;
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = &cmsgbuf.buf;
+ msg.msg_controllen = sizeof(cmsgbuf.buf);
+
+ if ((ifd = calloc(1, sizeof(struct imsg_fd))) == NULL)
+ return -1;
+
+again:
+#ifdef __OpenBSD__
+ if (getdtablecount() + imsg_fd_overhead
+ + (int)((CMSG_SPACE(sizeof(int)) - CMSG_SPACE(0))
+ / sizeof(int))
+ >= getdtablesize()) {
+#else
+ if (available_fds(imsg_fd_overhead
+ + (CMSG_SPACE(sizeof(int)) - CMSG_SPACE(0))
+ / sizeof(int))) {
+#endif
+ errno = EAGAIN;
+ free(ifd);
+ return -1;
+ }
+
+ n = recvmsg(ibuf->fd, &msg, 0);
+ if (n == -1) {
+ if (errno == EINTR)
+ goto again;
+ goto fail;
+ }
+
+ ibuf->r.wpos += n;
+
+ for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
+ cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+ if (cmsg->cmsg_level == SOL_SOCKET
+ && cmsg->cmsg_type == SCM_RIGHTS) {
+ int i;
+ int j;
+
+ /*
+ * We only accept one file descriptor. Due to C
+ * padding rules, our control buffer might contain
+ * more than one fd, and we must close them.
+ */
+ j = ((char *)cmsg + cmsg->cmsg_len
+ - (char *)CMSG_DATA(cmsg))
+ / sizeof(int);
+ for (i = 0; i < j; i++) {
+ fd = ((int *)CMSG_DATA(cmsg))[i];
+ if (ifd != NULL) {
+ ifd->fd = fd;
+ TAILQ_INSERT_TAIL(&ibuf->fds, ifd,
+ entry);
+ ifd = NULL;
+ } else
+ close(fd);
+ }
+ }
+ /* we do not handle other ctl data level */
+ }
+
+fail:
+ free(ifd);
+ return (n);
+}
+
+ssize_t imsg_get(struct imsgbuf *ibuf, struct imsg *imsg)
+{
+ size_t av, left, datalen;
+
+ av = ibuf->r.wpos;
+
+ if (IMSG_HEADER_SIZE > av)
+ return 0;
+
+ memcpy(&imsg->hdr, ibuf->r.buf, sizeof(imsg->hdr));
+ if (imsg->hdr.len < IMSG_HEADER_SIZE || imsg->hdr.len > MAX_IMSGSIZE) {
+ errno = ERANGE;
+ return -1;
+ }
+ if (imsg->hdr.len > av)
+ return 0;
+ datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
+ ibuf->r.rptr = ibuf->r.buf + IMSG_HEADER_SIZE;
+ if (datalen == 0)
+ imsg->data = NULL;
+ else if ((imsg->data = malloc(datalen)) == NULL)
+ return -1;
+
+ if (imsg->hdr.flags & IMSGF_HASFD)
+ imsg->fd = imsg_get_fd(ibuf);
+ else
+ imsg->fd = -1;
+
+ if (imsg->data)
+ memcpy(imsg->data, ibuf->r.rptr, datalen);
+
+ if (imsg->hdr.len < av) {
+ left = av - imsg->hdr.len;
+ memmove(&ibuf->r.buf, ibuf->r.buf + imsg->hdr.len, left);
+ ibuf->r.wpos = left;
+ } else
+ ibuf->r.wpos = 0;
+
+ return (datalen + IMSG_HEADER_SIZE);
+}
+
+int imsg_compose(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid,
+ pid_t pid, int fd, const void *data, uint16_t datalen)
+{
+ struct ibuf *wbuf;
+
+ if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL)
+ return -1;
+
+ if (imsg_add(wbuf, data, datalen) == -1)
+ return -1;
+
+ wbuf->fd = fd;
+
+ imsg_close(ibuf, wbuf);
+
+ return 1;
+}
+
+int imsg_composev(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid,
+ pid_t pid, int fd, const struct iovec *iov, int iovcnt)
+{
+ struct ibuf *wbuf;
+ int i, datalen = 0;
+
+ for (i = 0; i < iovcnt; i++)
+ datalen += iov[i].iov_len;
+
+ if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL)
+ return -1;
+
+ for (i = 0; i < iovcnt; i++)
+ if (imsg_add(wbuf, iov[i].iov_base, iov[i].iov_len) == -1)
+ return -1;
+
+ wbuf->fd = fd;
+
+ imsg_close(ibuf, wbuf);
+
+ return 1;
+}
+
+/* ARGSUSED */
+struct ibuf *imsg_create(struct imsgbuf *ibuf, uint32_t type, uint32_t peerid,
+ pid_t pid, uint16_t datalen)
+{
+ struct ibuf *wbuf;
+ struct imsg_hdr hdr;
+
+ memset(&hdr, 0x00, IMSG_HEADER_SIZE);
+
+ datalen += IMSG_HEADER_SIZE;
+ if (datalen > MAX_IMSGSIZE) {
+ errno = ERANGE;
+ return NULL;
+ }
+
+ hdr.type = type;
+ hdr.flags = 0;
+ hdr.peerid = peerid;
+ if ((hdr.pid = pid) == 0)
+ hdr.pid = ibuf->pid;
+ if ((wbuf = ibuf_dynamic(datalen, MAX_IMSGSIZE)) == NULL) {
+ return NULL;
+ }
+ if (imsg_add(wbuf, &hdr, sizeof(hdr)) == -1)
+ return NULL;
+
+ return (wbuf);
+}
+
+int imsg_add(struct ibuf *msg, const void *data, uint16_t datalen)
+{
+ if (datalen)
+ if (ibuf_add(msg, data, datalen) == -1) {
+ ibuf_free(msg);
+ return -1;
+ }
+ return (datalen);
+}
+
+void imsg_close(struct imsgbuf *ibuf, struct ibuf *msg)
+{
+ struct imsg_hdr *hdr;
+
+ hdr = (struct imsg_hdr *)msg->buf;
+
+ hdr->flags &= ~IMSGF_HASFD;
+ if (msg->fd != -1)
+ hdr->flags |= IMSGF_HASFD;
+
+ hdr->len = (uint16_t)msg->wpos;
+
+ ibuf_close(&ibuf->w, msg);
+}
+
+void imsg_free(struct imsg *imsg)
+{
+ free(imsg->data);
+}
+
+int imsg_get_fd(struct imsgbuf *ibuf)
+{
+ int fd;
+ struct imsg_fd *ifd;
+
+ if ((ifd = TAILQ_POP_FIRST(&ibuf->fds, entry)) == NULL)
+ return -1;
+
+ fd = ifd->fd;
+ free(ifd);
+
+ return (fd);
+}
+
+int imsg_flush(struct imsgbuf *ibuf)
+{
+ while (ibuf->w.queued)
+ if (msgbuf_write(&ibuf->w) <= 0)
+ return -1;
+ return 0;
+}
+
+void imsg_clear(struct imsgbuf *ibuf)
+{
+ int fd;
+
+ msgbuf_clear(&ibuf->w);
+ while ((fd = imsg_get_fd(ibuf)) != -1)
+ close(fd);
+}