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#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#include "rnd.h"
#include "die.h"
#include "ioexact.h"
#include "ioops.h"

static int fdw = -1;

static void randombytes_weak(unsigned char *x, unsigned long long xlen)
{
	int ret;

	if (fdw == -1) {
		for (;;) {
			fdw = open(LOW_ENTROPY_SOURCE, O_RDONLY);
			if (fdw != -1)
				break;
			sleep(1);
		}
	}

	while (xlen > 0) {
		if (xlen < 1048576)
			ret = xlen;
		else
			ret = 1048576;

		ret = read(fdw, x, ret);
		if (ret < 1) {
			sleep(1);
			continue;
		}

		x += ret;
		xlen -= ret;
	}
}

static void randombytes_strong(unsigned char *x, unsigned long long xlen)
{
	int fds, ret;

	fds = open_or_die(HIG_ENTROPY_SOURCE, O_RDONLY);

	ret = read_exact(fds, x, xlen, 0);
	if (ret != xlen)
		panic("Error reading from entropy source!\n");

	close(fds);
}

int secrand(void)
{
	int ret;

	randombytes_weak((void *) &ret, sizeof(ret));

	return ret;
}

void gen_key_bytes(unsigned char *area, size_t len)
{
	randombytes_strong(area, len);
}
dates" * tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits) dma-buf: Extract dma-buf.rst Update Documentation/00-INDEX docs: 00-INDEX: document directories/files with no docs docs: 00-INDEX: remove non-existing entries docs: 00-INDEX: add missing entries for documentation files/dirs docs: 00-INDEX: consolidate process/ and admin-guide/ description scripts: add a script to check if Documentation/00-INDEX is sane Docs: change sh -> awk in REPORTING-BUGS Documentation/core-api/device_link: Add initial documentation core-api: remove an unexpected unident ppc/idle: Add documentation for powersave=off Doc: Correct typo, "Introdution" => "Introduction" Documentation/atomic_ops.txt: convert to ReST markup Documentation/local_ops.txt: convert to ReST markup Documentation/assoc_array.txt: convert to ReST markup docs-rst: parse-headers.pl: cleanup the documentation docs-rst: fix media cleandocs target docs-rst: media/Makefile: reorganize the rules docs-rst: media: build SVG from graphviz files docs-rst: replace bayer.png by a SVG image ...
Diffstat (limited to 'Documentation/security')