From 610d801297fe7e46c319e6da4e6571aaded630dd Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Wed, 17 Aug 2016 01:33:02 -0400 Subject: more --- src/grp-initprogs/systemd-random-seed/Makefile | 50 ++++++ .../systemd-random-seed/random-seed.c | 176 +++++++++++++++++++++ .../systemd-random-seed.service.in | 22 +++ 3 files changed, 248 insertions(+) create mode 100644 src/grp-initprogs/systemd-random-seed/Makefile create mode 100644 src/grp-initprogs/systemd-random-seed/random-seed.c create mode 100644 src/grp-initprogs/systemd-random-seed/systemd-random-seed.service.in (limited to 'src/grp-initprogs/systemd-random-seed') diff --git a/src/grp-initprogs/systemd-random-seed/Makefile b/src/grp-initprogs/systemd-random-seed/Makefile new file mode 100644 index 0000000000..489a8ab007 --- /dev/null +++ b/src/grp-initprogs/systemd-random-seed/Makefile @@ -0,0 +1,50 @@ +# -*- Mode: makefile; indent-tabs-mode: t -*- +# +# This file is part of systemd. +# +# Copyright 2010-2012 Lennart Poettering +# Copyright 2010-2012 Kay Sievers +# Copyright 2013 Zbigniew Jędrzejewski-Szmek +# Copyright 2013 David Strauss +# Copyright 2016 Luke Shumaker +# +# systemd is free software; you can redistribute it and/or modify it +# under the terms of the GNU Lesser General Public License as published by +# the Free Software Foundation; either version 2.1 of the License, or +# (at your option) any later version. +# +# systemd is distributed in the hope that it will be useful, but +# WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with systemd; If not, see . +include $(dir $(lastword $(MAKEFILE_LIST)))/../../../config.mk +include $(topsrcdir)/build-aux/Makefile.head.mk + +ifneq ($(ENABLE_RANDOMSEED),) +rootlibexec_PROGRAMS += \ + systemd-random-seed + +nodist_systemunit_DATA += \ + units/systemd-random-seed.service + +systemd_random_seed_SOURCES = \ + src/random-seed/random-seed.c + +systemd_random_seed_LDADD = \ + libshared.la + +SYSINIT_TARGET_WANTS += \ + systemd-random-seed.service + +endif # ENABLE_RANDOMSEED + +EXTRA_DIST += \ + units/systemd-random-seed.service.in + +sd.CPPFLAGS += -DRANDOM_SEED_DIR=\"$(localstatedir)/lib/systemd/\" +sd.CPPFLAGS += -DRANDOM_SEED=\"$(localstatedir)/lib/systemd/random-seed\" + +include $(topsrcdir)/build-aux/Makefile.tail.mk diff --git a/src/grp-initprogs/systemd-random-seed/random-seed.c b/src/grp-initprogs/systemd-random-seed/random-seed.c new file mode 100644 index 0000000000..7fea6069f3 --- /dev/null +++ b/src/grp-initprogs/systemd-random-seed/random-seed.c @@ -0,0 +1,176 @@ +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include +#include +#include +#include + +#include "basic/alloc-util.h" +#include "basic/fd-util.h" +#include "basic/io-util.h" +#include "basic/log.h" +#include "basic/mkdir.h" +#include "basic/string-util.h" +#include "basic/util.h" + +#define POOL_SIZE_MIN 512 + +int main(int argc, char *argv[]) { + _cleanup_close_ int seed_fd = -1, random_fd = -1; + _cleanup_free_ void* buf = NULL; + size_t buf_size = 0; + ssize_t k; + int r, open_rw_error; + FILE *f; + bool refresh_seed_file = true; + + if (argc != 2) { + log_error("This program requires one argument."); + return EXIT_FAILURE; + } + + log_set_target(LOG_TARGET_AUTO); + log_parse_environment(); + log_open(); + + umask(0022); + + /* Read pool size, if possible */ + f = fopen("/proc/sys/kernel/random/poolsize", "re"); + if (f) { + if (fscanf(f, "%zu", &buf_size) > 0) + /* poolsize is in bits on 2.6, but we want bytes */ + buf_size /= 8; + + fclose(f); + } + + if (buf_size <= POOL_SIZE_MIN) + buf_size = POOL_SIZE_MIN; + + buf = malloc(buf_size); + if (!buf) { + r = log_oom(); + goto finish; + } + + r = mkdir_parents_label(RANDOM_SEED, 0755); + if (r < 0) { + log_error_errno(r, "Failed to create directory " RANDOM_SEED_DIR ": %m"); + goto finish; + } + + /* When we load the seed we read it and write it to the device + * and then immediately update the saved seed with new data, + * to make sure the next boot gets seeded differently. */ + + if (streq(argv[1], "load")) { + + seed_fd = open(RANDOM_SEED, O_RDWR|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600); + open_rw_error = -errno; + if (seed_fd < 0) { + refresh_seed_file = false; + + seed_fd = open(RANDOM_SEED, O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (seed_fd < 0) { + bool missing = errno == ENOENT; + + log_full_errno(missing ? LOG_DEBUG : LOG_ERR, + open_rw_error, "Failed to open " RANDOM_SEED " for writing: %m"); + r = log_full_errno(missing ? LOG_DEBUG : LOG_ERR, + errno, "Failed to open " RANDOM_SEED " for reading: %m"); + if (missing) + r = 0; + + goto finish; + } + } + + random_fd = open("/dev/urandom", O_RDWR|O_CLOEXEC|O_NOCTTY, 0600); + if (random_fd < 0) { + random_fd = open("/dev/urandom", O_WRONLY|O_CLOEXEC|O_NOCTTY, 0600); + if (random_fd < 0) { + r = log_error_errno(errno, "Failed to open /dev/urandom: %m"); + goto finish; + } + } + + k = loop_read(seed_fd, buf, buf_size, false); + if (k < 0) + r = log_error_errno(k, "Failed to read seed from " RANDOM_SEED ": %m"); + else if (k == 0) { + r = 0; + log_debug("Seed file " RANDOM_SEED " not yet initialized, proceeding."); + } else { + (void) lseek(seed_fd, 0, SEEK_SET); + + r = loop_write(random_fd, buf, (size_t) k, false); + if (r < 0) + log_error_errno(r, "Failed to write seed to /dev/urandom: %m"); + } + + } else if (streq(argv[1], "save")) { + + seed_fd = open(RANDOM_SEED, O_WRONLY|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600); + if (seed_fd < 0) { + r = log_error_errno(errno, "Failed to open " RANDOM_SEED ": %m"); + goto finish; + } + + random_fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (random_fd < 0) { + r = log_error_errno(errno, "Failed to open /dev/urandom: %m"); + goto finish; + } + + } else { + log_error("Unknown verb '%s'.", argv[1]); + r = -EINVAL; + goto finish; + } + + if (refresh_seed_file) { + + /* This is just a safety measure. Given that we are root and + * most likely created the file ourselves the mode and owner + * should be correct anyway. */ + (void) fchmod(seed_fd, 0600); + (void) fchown(seed_fd, 0, 0); + + k = loop_read(random_fd, buf, buf_size, false); + if (k < 0) { + r = log_error_errno(k, "Failed to read new seed from /dev/urandom: %m"); + goto finish; + } + if (k == 0) { + log_error("Got EOF while reading from /dev/urandom."); + r = -EIO; + goto finish; + } + + r = loop_write(seed_fd, buf, (size_t) k, false); + if (r < 0) + log_error_errno(r, "Failed to write new random seed file: %m"); + } + +finish: + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} diff --git a/src/grp-initprogs/systemd-random-seed/systemd-random-seed.service.in b/src/grp-initprogs/systemd-random-seed/systemd-random-seed.service.in new file mode 100644 index 0000000000..115233268d --- /dev/null +++ b/src/grp-initprogs/systemd-random-seed/systemd-random-seed.service.in @@ -0,0 +1,22 @@ +# This file is part of systemd. +# +# systemd is free software; you can redistribute it and/or modify it +# under the terms of the GNU Lesser General Public License as published by +# the Free Software Foundation; either version 2.1 of the License, or +# (at your option) any later version. + +[Unit] +Description=Load/Save Random Seed +Documentation=man:systemd-random-seed.service(8) man:random(4) +DefaultDependencies=no +RequiresMountsFor=@RANDOM_SEED@ +Conflicts=shutdown.target +After=systemd-remount-fs.service +Before=sysinit.target shutdown.target + +[Service] +Type=oneshot +RemainAfterExit=yes +ExecStart=@rootlibexecdir@/systemd-random-seed load +ExecStop=@rootlibexecdir@/systemd-random-seed save +TimeoutSec=30s -- cgit v1.2.3-54-g00ecf