1 files changed, 357 insertions, 0 deletions
diff --git a/lib/libcasper/libcasper/libcasper.c b/lib/libcasper/libcasper/libcasper.c
new file mode 100644
index 000000000000..9cc008cdb7bc
--- /dev/null
+++ b/lib/libcasper/libcasper/libcasper.c
@@ -0,0 +1,357 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2012-2013 The FreeBSD Foundation
+ * Copyright (c) 2015 Mariusz Zaborski <oshogbo@FreeBSD.org>
+ * All rights reserved.
+ *
+ * This software was developed by Pawel Jakub Dawidek under sponsorship from
+ * the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/nv.h>
+#include <sys/procdesc.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "libcasper.h"
+#include "libcasper_impl.h"
+
+#define	CASPER_VALID_FLAGS	(CASPER_NO_UNIQ)
+
+/*
+ * Structure describing communication channel between two separated processes.
+ */
+#define	CAP_CHANNEL_MAGIC	0xcac8a31
+struct cap_channel {
+	/*
+	 * Magic value helps to ensure that a pointer to the right structure is
+	 * passed to our functions.
+	 */
+	int	cch_magic;
+	/* Socket descriptor for IPC. */
+	int	cch_sock;
+	/* Process descriptor for casper. */
+	int	cch_pd;
+	/* Flags to communicate with casper. */
+	int	cch_flags;
+};
+
+static bool
+cap_add_pd(cap_channel_t *chan, int pd)
+{
+
+	if (!fd_is_valid(pd))
+		return (false);
+	chan->cch_pd = pd;
+	return (true);
+}
+
+int
+cap_channel_flags(const cap_channel_t *chan)
+{
+
+	return (chan->cch_flags);
+}
+
+cap_channel_t *
+cap_init(void)
+{
+	pid_t pid;
+	int sock[2], serrno, pfd;
+	bool ret;
+	cap_channel_t *chan;
+
+	if (socketpair(PF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0,
+	    sock) == -1) {
+		return (NULL);
+	}
+
+	pid = pdfork(&pfd, 0);
+	if (pid == 0) {
+		/* Child. */
+		close(sock[0]);
+		casper_main_loop(sock[1]);
+		/* NOTREACHED. */
+	} else if (pid > 0) {
+		/* Parent. */
+		close(sock[1]);
+		chan = cap_wrap(sock[0], 0);
+		if (chan == NULL) {
+			serrno = errno;
+			close(sock[0]);
+			close(pfd);
+			errno = serrno;
+			return (NULL);
+		}
+		ret = cap_add_pd(chan, pfd);
+		assert(ret);
+		return (chan);
+	}
+
+	/* Error. */
+	serrno = errno;
+	close(sock[0]);
+	close(sock[1]);
+	errno = serrno;
+	return (NULL);
+}
+
+cap_channel_t *
+cap_wrap(int sock, int flags)
+{
+	cap_channel_t *chan;
+
+	if (!fd_is_valid(sock))
+		return (NULL);
+
+	if ((flags & CASPER_VALID_FLAGS) != flags)
+		return (NULL);
+
+	chan = malloc(sizeof(*chan));
+	if (chan != NULL) {
+		chan->cch_sock = sock;
+		chan->cch_pd = -1;
+		chan->cch_flags = flags;
+		chan->cch_magic = CAP_CHANNEL_MAGIC;
+	}
+
+	return (chan);
+}
+
+int
+cap_unwrap(cap_channel_t *chan, int *flags)
+{
+	int sock;
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	sock = chan->cch_sock;
+	if (chan->cch_pd != -1)
+		close(chan->cch_pd);
+	if (flags != NULL)
+		*flags = chan->cch_flags;
+	chan->cch_magic = 0;
+	free(chan);
+
+	return (sock);
+}
+
+cap_channel_t *
+cap_clone(const cap_channel_t *chan)
+{
+	cap_channel_t *newchan;
+	nvlist_t *nvl;
+	int newsock;
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	nvl = nvlist_create(channel_nvlist_flags(chan));
+	nvlist_add_string(nvl, "cmd", "clone");
+	nvl = cap_xfer_nvlist(chan, nvl);
+	if (nvl == NULL)
+		return (NULL);
+	if (nvlist_get_number(nvl, "error") != 0) {
+		errno = (int)nvlist_get_number(nvl, "error");
+		nvlist_destroy(nvl);
+		return (NULL);
+	}
+	newsock = nvlist_take_descriptor(nvl, "sock");
+	nvlist_destroy(nvl);
+	newchan = cap_wrap(newsock, chan->cch_flags);
+	if (newchan == NULL) {
+		int serrno;
+
+		serrno = errno;
+		close(newsock);
+		errno = serrno;
+	}
+
+	return (newchan);
+}
+
+void
+cap_close(cap_channel_t *chan)
+{
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	chan->cch_magic = 0;
+	if (chan->cch_pd != -1)
+		close(chan->cch_pd);
+	close(chan->cch_sock);
+	free(chan);
+}
+
+int
+cap_sock(const cap_channel_t *chan)
+{
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	return (chan->cch_sock);
+}
+
+int
+cap_limit_set(const cap_channel_t *chan, nvlist_t *limits)
+{
+	nvlist_t *nvlmsg;
+	int error;
+
+	nvlmsg = nvlist_create(channel_nvlist_flags(chan));
+	nvlist_add_string(nvlmsg, "cmd", "limit_set");
+	nvlist_add_nvlist(nvlmsg, "limits", limits);
+	nvlmsg = cap_xfer_nvlist(chan, nvlmsg);
+	if (nvlmsg == NULL) {
+		nvlist_destroy(limits);
+		return (-1);
+	}
+	error = (int)nvlist_get_number(nvlmsg, "error");
+	nvlist_destroy(nvlmsg);
+	nvlist_destroy(limits);
+	if (error != 0) {
+		errno = error;
+		return (-1);
+	}
+	return (0);
+}
+
+int
+cap_limit_get(const cap_channel_t *chan, nvlist_t **limitsp)
+{
+	nvlist_t *nvlmsg;
+	int error;
+
+	nvlmsg = nvlist_create(channel_nvlist_flags(chan));
+	nvlist_add_string(nvlmsg, "cmd", "limit_get");
+	nvlmsg = cap_xfer_nvlist(chan, nvlmsg);
+	if (nvlmsg == NULL)
+		return (-1);
+	error = (int)nvlist_get_number(nvlmsg, "error");
+	if (error != 0) {
+		nvlist_destroy(nvlmsg);
+		errno = error;
+		return (-1);
+	}
+	if (nvlist_exists_null(nvlmsg, "limits"))
+		*limitsp = NULL;
+	else
+		*limitsp = nvlist_take_nvlist(nvlmsg, "limits");
+	nvlist_destroy(nvlmsg);
+	return (0);
+}
+
+int
+cap_send_nvlist(const cap_channel_t *chan, const nvlist_t *nvl)
+{
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	return (nvlist_send(chan->cch_sock, nvl));
+}
+
+nvlist_t *
+cap_recv_nvlist(const cap_channel_t *chan)
+{
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	return (nvlist_recv(chan->cch_sock,
+	    channel_nvlist_flags(chan)));
+}
+
+nvlist_t *
+cap_xfer_nvlist(const cap_channel_t *chan, nvlist_t *nvl)
+{
+
+	assert(chan != NULL);
+	assert(chan->cch_magic == CAP_CHANNEL_MAGIC);
+
+	return (nvlist_xfer(chan->cch_sock, nvl,
+	    channel_nvlist_flags(chan)));
+}
+
+cap_channel_t *
+cap_service_open(const cap_channel_t *chan, const char *name)
+{
+	cap_channel_t *newchan;
+	nvlist_t *nvl;
+	int sock, error;
+	int flags;
+
+	sock = -1;
+
+	nvl = nvlist_create(channel_nvlist_flags(chan));
+	nvlist_add_string(nvl, "cmd", "open");
+	nvlist_add_string(nvl, "service", name);
+	nvl = cap_xfer_nvlist(chan, nvl);
+	if (nvl == NULL)
+		return (NULL);
+	error = (int)nvlist_get_number(nvl, "error");
+	if (error != 0) {
+		nvlist_destroy(nvl);
+		errno = error;
+		return (NULL);
+	}
+	sock = nvlist_take_descriptor(nvl, "chanfd");
+	flags = nvlist_take_number(nvl, "chanflags");
+	assert(sock >= 0);
+	nvlist_destroy(nvl);
+	nvl = NULL;
+	newchan = cap_wrap(sock, flags);
+	if (newchan == NULL)
+		goto fail;
+	return (newchan);
+fail:
+	error = errno;
+	close(sock);
+	errno = error;
+	return (NULL);
+}
+
+int
+cap_service_limit(const cap_channel_t *chan, const char * const *names,
+    size_t nnames)
+{
+	nvlist_t *limits;
+	unsigned int i;
+
+	limits = nvlist_create(channel_nvlist_flags(chan));
+	for (i = 0; i < nnames; i++)
+		nvlist_add_null(limits, names[i]);
+	return (cap_limit_set(chan, limits));
+}