Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 316 insertions, 0 deletions

diff --git a/lib/imsg.c b/lib/imsg.c
new file mode 100644
index 0000000..057e4b3
--- /dev/null
+++ b/lib/imsg.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: ISC
+/*	$OpenBSD$	*/
+
+/*
+ * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
+ */
+
+#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);
+}