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-rw-r--r--main/openrc/seedrng.patch619
1 files changed, 619 insertions, 0 deletions
diff --git a/main/openrc/seedrng.patch b/main/openrc/seedrng.patch
new file mode 100644
index 00000000000..4f06f1e8016
--- /dev/null
+++ b/main/openrc/seedrng.patch
@@ -0,0 +1,619 @@
+From 076c2552aeff88a27fe275dfaae61dedf4bb4bd5 Mon Sep 17 00:00:00 2001
+From: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Date: Thu, 24 Mar 2022 22:07:16 -0600
+Subject: [PATCH] Use seedrng for seeding the random number generator
+
+The RNG can't actually be seeded from a shell script, due to the
+reliance on ioctls. For this reason, the seedrng project provides a
+basic script meant to be copy and pasted into projects like OpenRC and
+tweaked as needed: https://git.zx2c4.com/seedrng/about/
+
+This commit imports it into OpenRC and wires up /etc/init.d/urandom to
+call it. It shouldn't be called by other things on the system, so it
+lives in rc_sbindir.
+
+Closes #506.
+Closes #507.
+
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+---
+ AUTHORS | 1 +
+ conf.d/urandom | 9 +-
+ init.d/urandom.in | 41 ++--
+ src/rc/Makefile | 6 +-
+ src/rc/meson.build | 10 +-
+ src/rc/seedrng.c | 453 +++++++++++++++++++++++++++++++++++++++++++++
+ 6 files changed, 499 insertions(+), 21 deletions(-)
+ create mode 100644 src/rc/seedrng.c
+
+diff --git a/AUTHORS b/AUTHORS
+index 0616d5175..ede0f471b 100644
+--- a/AUTHORS
++++ b/AUTHORS
+@@ -43,6 +43,7 @@ Ian Stakenvicius <axs@gentoo.org>
+ Jakob Drexel <jake42@rommel.stw.uni-erlangen.de>
+ James Le Cuirot <chewi@aura-online.co.uk>
+ Jan Psota <jasiu@belsznica.pl>
++Jason A. Donenfeld <Jason@zx2c4.com>
+ Jason Zaman <jason@perfinion.com>
+ Joe Harvell <jharvell@dogpad.net>
+ Joe M <joe9mail@gmail.com>
+diff --git a/conf.d/urandom b/conf.d/urandom
+index f721a2491..744e4f702 100644
+--- a/conf.d/urandom
++++ b/conf.d/urandom
+@@ -2,4 +2,11 @@
+ # (say for crypt swap), so you will need to customize this
+ # behavior. If you have /var on a separate partition, then
+ # make sure this path lives on your root device somewhere.
+-urandom_seed="/var/lib/misc/random-seed"
++seed_dir="/var/lib/seedrng"
++lock_file="/var/run/seedrng.lock"
++
++# Set this to true if you do not want seed files to actually
++# credit the RNG. Set this if you plan to replicate this
++# file system image and do not have the wherewithal to first
++# delete the contents of /var/lib/seedrng.
++skip_credit="false"
+diff --git a/init.d/urandom.in b/init.d/urandom.in
+index 0d6ab66e0..cda431fdb 100644
+--- a/init.d/urandom.in
++++ b/init.d/urandom.in
+@@ -1,5 +1,5 @@
+ #!@SBINDIR@/openrc-run
+-# Copyright (c) 2007-2015 The OpenRC Authors.
++# Copyright (c) 2007-2022 The OpenRC Authors.
+ # See the Authors file at the top-level directory of this distribution and
+ # https://github.com/OpenRC/openrc/blob/HEAD/AUTHORS
+ #
+@@ -9,7 +9,10 @@
+ # This file may not be copied, modified, propagated, or distributed
+ # except according to the terms contained in the LICENSE file.
+
+-: ${urandom_seed:=${URANDOM_SEED:-/var/lib/misc/random-seed}}
++export SEEDRNG_SEED_DIR="${seed_dir:-/var/lib/seedrng}"
++export SEEDRNG_LOCK_FILE="${lock_file:-/var/run/seedrng.lock}"
++export SEEDRNG_SKIP_CREDIT="${skip_credit:-false}"
++: ${urandom_seed:=${SEEDRNG_SEED_DIR}/../misc/random-seed}
+ description="Initializes the random number generator."
+
+ depend()
+@@ -21,33 +24,35 @@ depend()
+
+ save_seed()
+ {
+- local psz=1
+-
+- if [ -e /proc/sys/kernel/random/poolsize ]; then
+- : $(( psz = $(cat /proc/sys/kernel/random/poolsize) / 4096 ))
+- fi
+-
+ ( # sub shell to prevent umask pollution
+ umask 077
+- dd if=/dev/urandom of="$urandom_seed" count=${psz} 2>/dev/null
++ dd if=/dev/urandom of="$urandom_seed" count=1 2>/dev/null
+ )
+ }
+
+ start()
+ {
+- [ -c /dev/urandom ] || return
+- if [ -f "$urandom_seed" ]; then
+- ebegin "Initializing random number generator"
+- cat "$urandom_seed" > /dev/urandom
+- eend $? "Error initializing random number generator"
++ if [ "$RC_UNAME" = Linux ]; then
++ seedrng
++ else
++ [ -c /dev/urandom ] || return
++ if [ -f "$urandom_seed" ]; then
++ ebegin "Initializing random number generator"
++ cat "$urandom_seed" > /dev/urandom
++ eend $? "Error initializing random number generator"
++ fi
++ rm -f "$urandom_seed" && save_seed
+ fi
+- rm -f "$urandom_seed" && save_seed
+ return 0
+ }
+
+ stop()
+ {
+- ebegin "Saving random seed"
+- save_seed
+- eend $? "Failed to save random seed"
++ if [ "$RC_UNAME" = Linux ]; then
++ seedrng
++ else
++ ebegin "Saving random seed"
++ save_seed
++ eend $? "Failed to save random seed"
++ fi
+ }
+diff --git a/src/rc/Makefile b/src/rc/Makefile
+index fd796d920..62539f134 100644
+--- a/src/rc/Makefile
++++ b/src/rc/Makefile
+@@ -15,7 +15,7 @@ endif
+
+ ifeq (${OS},Linux)
+ SRCS+= kill_all.c openrc-init.c openrc-shutdown.c rc-sysvinit.c broadcast.c \
+- rc-wtmp.c
++ rc-wtmp.c seedrng.c
+ endif
+
+ CLEANFILES= version.h rc-selinux.o
+@@ -47,6 +47,7 @@ RC_SBINPROGS= mark_service_starting mark_service_started \
+
+ ifeq (${OS},Linux)
+ RC_BINPROGS+= kill_all
++RC_SBINPROGS+= seedrng
+ SBINPROGS+= openrc-init openrc-shutdown
+ endif
+
+@@ -180,3 +181,6 @@ shell_var: shell_var.o
+
+ swclock: swclock.o _usage.o rc-misc.o
+ ${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
++
++seedrng: seedrng.o
++ ${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
+diff --git a/src/rc/seedrng.c b/src/rc/seedrng.c
+new file mode 100644
+index 000000000..c1f941457
+--- /dev/null
++++ b/src/rc/seedrng.c
+@@ -0,0 +1,453 @@
++/*
++ * seedrng.c
++ * Seed kernel RNG from seed file, based on code from:
++ * https://git.zx2c4.com/seedrng/about/
++ */
++
++/*
++ * Copyright (c) 2022 The OpenRC Authors.
++ * See the Authors file at the top-level directory of this distribution and
++ * https://github.com/OpenRC/openrc/blob/HEAD/AUTHORS
++ *
++ * This file is part of OpenRC. It is subject to the license terms in
++ * the LICENSE file found in the top-level directory of this
++ * distribution and at https://github.com/OpenRC/openrc/blob/HEAD/LICENSE
++ * This file may not be copied, modified, propagated, or distributed
++ * except according to the terms contained in the LICENSE file.
++ */
++
++#include <linux/random.h>
++#include <sys/random.h>
++#include <sys/ioctl.h>
++#include <sys/file.h>
++#include <sys/stat.h>
++#include <sys/types.h>
++#include <fcntl.h>
++#include <poll.h>
++#include <unistd.h>
++#include <time.h>
++#include <errno.h>
++#include <endian.h>
++#include <stdbool.h>
++#include <stdint.h>
++#include <string.h>
++#include <stdio.h>
++#include <stdlib.h>
++
++#include "rc.h"
++#include "einfo.h"
++#include "helpers.h"
++
++#ifndef GRND_INSECURE
++#define GRND_INSECURE 0x0004 /* Apparently some headers don't ship with this yet. */
++#endif
++
++static const char *SEED_DIR;
++static const char *LOCK_FILE;
++static char *CREDITABLE_SEED;
++static char *NON_CREDITABLE_SEED;
++
++enum blake2s_lengths {
++ BLAKE2S_BLOCK_LEN = 64,
++ BLAKE2S_HASH_LEN = 32,
++ BLAKE2S_KEY_LEN = 32
++};
++
++enum seedrng_lengths {
++ MAX_SEED_LEN = 512,
++ MIN_SEED_LEN = BLAKE2S_HASH_LEN
++};
++
++struct blake2s_state {
++ uint32_t h[8];
++ uint32_t t[2];
++ uint32_t f[2];
++ uint8_t buf[BLAKE2S_BLOCK_LEN];
++ unsigned int buflen;
++ unsigned int outlen;
++};
++
++#define le32_to_cpup(a) le32toh(*(a))
++#define cpu_to_le32(a) htole32(a)
++#ifndef ARRAY_SIZE
++#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
++#endif
++#ifndef DIV_ROUND_UP
++#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
++#endif
++
++static inline void cpu_to_le32_array(uint32_t *buf, unsigned int words)
++{
++ while (words--) {
++ *buf = cpu_to_le32(*buf);
++ ++buf;
++ }
++}
++
++static inline void le32_to_cpu_array(uint32_t *buf, unsigned int words)
++{
++ while (words--) {
++ *buf = le32_to_cpup(buf);
++ ++buf;
++ }
++}
++
++static inline uint32_t ror32(uint32_t word, unsigned int shift)
++{
++ return (word >> (shift & 31)) | (word << ((-shift) & 31));
++}
++
++static const uint32_t blake2s_iv[8] = {
++ 0x6A09E667UL, 0xBB67AE85UL, 0x3C6EF372UL, 0xA54FF53AUL,
++ 0x510E527FUL, 0x9B05688CUL, 0x1F83D9ABUL, 0x5BE0CD19UL
++};
++
++static const uint8_t blake2s_sigma[10][16] = {
++ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
++ { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
++ { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
++ { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
++ { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
++ { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
++ { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
++ { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
++ { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
++ { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 },
++};
++
++static void blake2s_set_lastblock(struct blake2s_state *state)
++{
++ state->f[0] = -1;
++}
++
++static void blake2s_increment_counter(struct blake2s_state *state, const uint32_t inc)
++{
++ state->t[0] += inc;
++ state->t[1] += (state->t[0] < inc);
++}
++
++static void blake2s_init_param(struct blake2s_state *state, const uint32_t param)
++{
++ int i;
++
++ memset(state, 0, sizeof(*state));
++ for (i = 0; i < 8; ++i)
++ state->h[i] = blake2s_iv[i];
++ state->h[0] ^= param;
++}
++
++static void blake2s_init(struct blake2s_state *state, const size_t outlen)
++{
++ blake2s_init_param(state, 0x01010000 | outlen);
++ state->outlen = outlen;
++}
++
++static void blake2s_compress(struct blake2s_state *state, const uint8_t *block, size_t nblocks, const uint32_t inc)
++{
++ uint32_t m[16];
++ uint32_t v[16];
++ int i;
++
++ while (nblocks > 0) {
++ blake2s_increment_counter(state, inc);
++ memcpy(m, block, BLAKE2S_BLOCK_LEN);
++ le32_to_cpu_array(m, ARRAY_SIZE(m));
++ memcpy(v, state->h, 32);
++ v[ 8] = blake2s_iv[0];
++ v[ 9] = blake2s_iv[1];
++ v[10] = blake2s_iv[2];
++ v[11] = blake2s_iv[3];
++ v[12] = blake2s_iv[4] ^ state->t[0];
++ v[13] = blake2s_iv[5] ^ state->t[1];
++ v[14] = blake2s_iv[6] ^ state->f[0];
++ v[15] = blake2s_iv[7] ^ state->f[1];
++
++#define G(r, i, a, b, c, d) do { \
++ a += b + m[blake2s_sigma[r][2 * i + 0]]; \
++ d = ror32(d ^ a, 16); \
++ c += d; \
++ b = ror32(b ^ c, 12); \
++ a += b + m[blake2s_sigma[r][2 * i + 1]]; \
++ d = ror32(d ^ a, 8); \
++ c += d; \
++ b = ror32(b ^ c, 7); \
++} while (0)
++
++#define ROUND(r) do { \
++ G(r, 0, v[0], v[ 4], v[ 8], v[12]); \
++ G(r, 1, v[1], v[ 5], v[ 9], v[13]); \
++ G(r, 2, v[2], v[ 6], v[10], v[14]); \
++ G(r, 3, v[3], v[ 7], v[11], v[15]); \
++ G(r, 4, v[0], v[ 5], v[10], v[15]); \
++ G(r, 5, v[1], v[ 6], v[11], v[12]); \
++ G(r, 6, v[2], v[ 7], v[ 8], v[13]); \
++ G(r, 7, v[3], v[ 4], v[ 9], v[14]); \
++} while (0)
++ ROUND(0);
++ ROUND(1);
++ ROUND(2);
++ ROUND(3);
++ ROUND(4);
++ ROUND(5);
++ ROUND(6);
++ ROUND(7);
++ ROUND(8);
++ ROUND(9);
++
++#undef G
++#undef ROUND
++
++ for (i = 0; i < 8; ++i)
++ state->h[i] ^= v[i] ^ v[i + 8];
++
++ block += BLAKE2S_BLOCK_LEN;
++ --nblocks;
++ }
++}
++
++static void blake2s_update(struct blake2s_state *state, const void *inp, size_t inlen)
++{
++ const size_t fill = BLAKE2S_BLOCK_LEN - state->buflen;
++ const uint8_t *in = inp;
++
++ if (!inlen)
++ return;
++ if (inlen > fill) {
++ memcpy(state->buf + state->buflen, in, fill);
++ blake2s_compress(state, state->buf, 1, BLAKE2S_BLOCK_LEN);
++ state->buflen = 0;
++ in += fill;
++ inlen -= fill;
++ }
++ if (inlen > BLAKE2S_BLOCK_LEN) {
++ const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_LEN);
++ blake2s_compress(state, in, nblocks - 1, BLAKE2S_BLOCK_LEN);
++ in += BLAKE2S_BLOCK_LEN * (nblocks - 1);
++ inlen -= BLAKE2S_BLOCK_LEN * (nblocks - 1);
++ }
++ memcpy(state->buf + state->buflen, in, inlen);
++ state->buflen += inlen;
++}
++
++static void blake2s_final(struct blake2s_state *state, uint8_t *out)
++{
++ blake2s_set_lastblock(state);
++ memset(state->buf + state->buflen, 0, BLAKE2S_BLOCK_LEN - state->buflen);
++ blake2s_compress(state, state->buf, 1, state->buflen);
++ cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
++ memcpy(out, state->h, state->outlen);
++}
++
++static size_t determine_optimal_seed_len(void)
++{
++ size_t ret = 0;
++ char poolsize_str[11] = { 0 };
++ int fd = open("/proc/sys/kernel/random/poolsize", O_RDONLY);
++
++ if (fd < 0 || read(fd, poolsize_str, sizeof(poolsize_str) - 1) < 0) {
++ ewarn("Unable to determine pool size, falling back to %u bits: %s", MIN_SEED_LEN * 8, strerror(errno));
++ ret = MIN_SEED_LEN;
++ } else
++ ret = DIV_ROUND_UP(strtoul(poolsize_str, NULL, 10), 8);
++ if (fd >= 0)
++ close(fd);
++ if (ret < MIN_SEED_LEN)
++ ret = MIN_SEED_LEN;
++ else if (ret > MAX_SEED_LEN)
++ ret = MAX_SEED_LEN;
++ return ret;
++}
++
++static int read_new_seed(uint8_t *seed, size_t len, bool *is_creditable)
++{
++ ssize_t ret;
++ int urandom_fd;
++
++ *is_creditable = false;
++ ret = getrandom(seed, len, GRND_NONBLOCK);
++ if (ret == (ssize_t)len) {
++ *is_creditable = true;
++ return 0;
++ }
++ if (ret == -1 && errno == ENOSYS) {
++ struct pollfd random_fd = {
++ .fd = open("/dev/random", O_RDONLY),
++ .events = POLLIN
++ };
++ if (random_fd.fd < 0)
++ return -errno;
++ *is_creditable = poll(&random_fd, 1, 0) == 1;
++ close(random_fd.fd);
++ } else if (getrandom(seed, len, GRND_INSECURE) == (ssize_t)len)
++ return 0;
++ urandom_fd = open("/dev/urandom", O_RDONLY);
++ if (urandom_fd < 0)
++ return -errno;
++ ret = read(urandom_fd, seed, len);
++ if (ret == (ssize_t)len)
++ ret = 0;
++ else
++ ret = -errno ? -errno : -EIO;
++ close(urandom_fd);
++ return ret;
++}
++
++static int seed_rng(uint8_t *seed, size_t len, bool credit)
++{
++ struct {
++ int entropy_count;
++ int buf_size;
++ uint8_t buffer[MAX_SEED_LEN];
++ } req = {
++ .entropy_count = credit ? len * 8 : 0,
++ .buf_size = len
++ };
++ int random_fd, ret;
++
++ if (len > sizeof(req.buffer))
++ return -EFBIG;
++ memcpy(req.buffer, seed, len);
++
++ random_fd = open("/dev/random", O_RDWR);
++ if (random_fd < 0)
++ return -errno;
++ ret = ioctl(random_fd, RNDADDENTROPY, &req);
++ if (ret)
++ ret = -errno ? -errno : -EIO;
++ close(random_fd);
++ return ret;
++}
++
++static int seed_from_file_if_exists(const char *filename, bool credit, struct blake2s_state *hash)
++{
++ uint8_t seed[MAX_SEED_LEN];
++ ssize_t seed_len;
++ int fd, dfd, ret = 0;
++
++ fd = open(filename, O_RDONLY);
++ if (fd < 0 && errno == ENOENT)
++ return 0;
++ else if (fd < 0) {
++ ret = -errno;
++ eerror("Unable to open seed file: %s", strerror(errno));
++ return ret;
++ }
++ dfd = open(SEED_DIR, O_DIRECTORY | O_RDONLY);
++ if (dfd < 0) {
++ ret = -errno;
++ close(fd);
++ eerror("Unable to open seed directory: %s", strerror(errno));
++ return ret;
++ }
++ seed_len = read(fd, seed, sizeof(seed));
++ if (seed_len < 0) {
++ ret = -errno;
++ eerror("Unable to read seed file: %s", strerror(errno));
++ }
++ close(fd);
++ if (ret) {
++ close(dfd);
++ return ret;
++ }
++ if ((unlink(filename) < 0 || fsync(dfd) < 0) && seed_len) {
++ ret = -errno;
++ eerror("Unable to remove seed after reading, so not seeding: %s", strerror(errno));
++ }
++ close(dfd);
++ if (ret)
++ return ret;
++ if (!seed_len)
++ return 0;
++
++ blake2s_update(hash, &seed_len, sizeof(seed_len));
++ blake2s_update(hash, seed, seed_len);
++
++ einfo("Seeding %zd bits %s crediting", seed_len * 8, credit ? "and" : "without");
++ ret = seed_rng(seed, seed_len, credit);
++ if (ret < 0)
++ eerror("Unable to seed: %s", strerror(-ret));
++ return ret;
++}
++
++static void populate_global_paths(void)
++{
++ SEED_DIR = getenv("SEEDRNG_SEED_DIR");
++ if (!SEED_DIR || !*SEED_DIR)
++ SEED_DIR = "/var/lib/seedrng";
++ LOCK_FILE = getenv("SEEDRNG_LOCK_FILE");
++ if (!LOCK_FILE || !*LOCK_FILE)
++ LOCK_FILE = "/var/run/seedrng.lock";
++ xasprintf(&CREDITABLE_SEED, "%s/seed.credit", SEED_DIR);
++ xasprintf(&NON_CREDITABLE_SEED, "%s/seed.no-credit", SEED_DIR);
++}
++
++int main(int argc _unused, char *argv[] _unused)
++{
++ static const char seedrng_prefix[] = "SeedRNG v1 Old+New Prefix";
++ static const char seedrng_failure[] = "SeedRNG v1 No New Seed Failure";
++ int ret, fd, lock, program_ret = 0;
++ uint8_t new_seed[MAX_SEED_LEN];
++ size_t new_seed_len;
++ bool new_seed_creditable;
++ struct timespec realtime = { 0 }, boottime = { 0 };
++ struct blake2s_state hash;
++
++ umask(0077);
++ if (getuid())
++ eerrorx("This rc helper program requires root");
++
++ populate_global_paths();
++ blake2s_init(&hash, BLAKE2S_HASH_LEN);
++ blake2s_update(&hash, seedrng_prefix, strlen(seedrng_prefix));
++ clock_gettime(CLOCK_REALTIME, &realtime);
++ clock_gettime(CLOCK_BOOTTIME, &boottime);
++ blake2s_update(&hash, &realtime, sizeof(realtime));
++ blake2s_update(&hash, &boottime, sizeof(boottime));
++
++ if (mkdir(SEED_DIR, 0700) < 0 && errno != EEXIST)
++ eerrorx("Unable to create \"%s\" directory: %s", SEED_DIR, strerror(errno));
++
++ lock = open(LOCK_FILE, O_WRONLY | O_CREAT, 0000);
++ if (lock < 0 || flock(lock, LOCK_EX) < 0)
++ eerrorx("Unable to open lock file: %s", strerror(errno));
++
++ ret = seed_from_file_if_exists(NON_CREDITABLE_SEED, false, &hash);
++ if (ret < 0)
++ program_ret |= 1 << 1;
++ ret = seed_from_file_if_exists(CREDITABLE_SEED, !rc_yesno(getenv("SEEDRNG_SKIP_CREDIT")), &hash);
++ if (ret < 0)
++ program_ret |= 1 << 2;
++
++ new_seed_len = determine_optimal_seed_len();
++ ret = read_new_seed(new_seed, new_seed_len, &new_seed_creditable);
++ if (ret < 0) {
++ eerror("Unable to read new seed: %s", strerror(-ret));
++ new_seed_len = BLAKE2S_HASH_LEN;
++ strncpy((char *)new_seed, seedrng_failure, new_seed_len);
++ program_ret |= 1 << 3;
++ }
++ blake2s_update(&hash, &new_seed_len, sizeof(new_seed_len));
++ blake2s_update(&hash, new_seed, new_seed_len);
++ blake2s_final(&hash, new_seed + new_seed_len - BLAKE2S_HASH_LEN);
++
++ einfo("Saving %zu bits of %s seed for next boot", new_seed_len * 8, new_seed_creditable ? "creditable" : "non-creditable");
++ fd = open(NON_CREDITABLE_SEED, O_WRONLY | O_CREAT | O_TRUNC, 0400);
++ if (fd < 0) {
++ eerror("Unable to open seed file for writing: %s", strerror(errno));
++ program_ret |= 1 << 4;
++ goto out;
++ }
++ if (write(fd, new_seed, new_seed_len) != (ssize_t)new_seed_len || fsync(fd) < 0) {
++ eerror("Unable to write seed file: %s", strerror(errno));
++ program_ret |= 1 << 5;
++ goto out;
++ }
++ if (new_seed_creditable && rename(NON_CREDITABLE_SEED, CREDITABLE_SEED) < 0) {
++ ewarn("Unable to make new seed creditable: %s", strerror(errno));
++ program_ret |= 1 << 6;
++ }
++out:
++ close(fd);
++ close(lock);
++ return program_ret;
++}