freebsd-dev/lib/libcapsicum/libcapsicum_random.c
Pawel Jakub Dawidek 42a8595256 Please welcome casperd daemon. It (and its services) will be responsible for
giving access to functionality that is not available in capability mode
sandbox. The functionality can be precisely restricted.

Start with the following services:
- system.dns - provides API compatible to:
	- gethostbyname(3),
	- gethostbyname2(3),
	- gethostbyaddr(3),
	- getaddrinfo(3),
	- getnameinfo(3),
- system.grp - provides getgrent(3)-compatible API,
- system.pwd - provides getpwent(3)-compatible API,
- system.random - allows to obtain entropy from /dev/random,
- system.sysctl - provides sysctlbyname(3-compatible API.

Sponsored by:	The FreeBSD Foundation
2013-12-02 08:21:28 +00:00

81 lines
2.4 KiB
C

/*-
* Copyright (c) 2013 The FreeBSD Foundation
* 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <nv.h>
#include "libcapsicum.h"
#include "libcapsicum_random.h"
#define MAXSIZE (1024 * 1024)
int
cap_random_buf(cap_channel_t *chan, void *buf, size_t nbytes)
{
nvlist_t *nvl;
const void *randbuf;
uint8_t *ptr;
size_t left, randbufsize;
left = nbytes;
ptr = buf;
while (left > 0) {
nvl = nvlist_create(0);
nvlist_add_string(nvl, "cmd", "generate");
nvlist_add_number(nvl, "size",
(uint64_t)(left > MAXSIZE ? MAXSIZE : left));
nvl = cap_xfer_nvlist(chan, nvl);
if (nvl == NULL)
return (-1);
if (nvlist_get_number(nvl, "error") != 0) {
errno = (int)nvlist_get_number(nvl, "error");
nvlist_destroy(nvl);
return (-1);
}
randbuf = nvlist_get_binary(nvl, "data", &randbufsize);
memcpy(ptr, randbuf, randbufsize);
nvlist_destroy(nvl);
ptr += randbufsize;
assert(left >= randbufsize);
left -= randbufsize;
}
return (0);
}