Initial commit v1.0.0
authorPetr Štetiar <ynezz@true.cz>
Mon, 20 May 2019 09:24:49 +0000 (11:24 +0200)
committerPetr Štetiar <ynezz@true.cz>
Mon, 20 May 2019 12:18:36 +0000 (14:18 +0200)
Signed-off-by: Petr Štetiar <ynezz@true.cz>
.gitignore [new file with mode: 0644]
.gitmodules [new file with mode: 0644]
3rdparty/jitterentropy-rngd [new submodule]
CMakeLists.txt [new file with mode: 0644]
Makefile [new file with mode: 0644]
README.md [new file with mode: 0644]
cmake/openwrt-toolchain-ath79.cmake [new file with mode: 0644]
cmake/openwrt-toolchain-imx6.cmake [new file with mode: 0644]
log.h [new file with mode: 0644]
urngd.c [new file with mode: 0644]

diff --git a/.gitignore b/.gitignore
new file mode 100644 (file)
index 0000000..df20789
--- /dev/null
@@ -0,0 +1,2 @@
+local.mk
+build*
diff --git a/.gitmodules b/.gitmodules
new file mode 100644 (file)
index 0000000..c892b92
--- /dev/null
@@ -0,0 +1,3 @@
+[submodule "3rdparty/jitterentropy-rngd"]
+       path = 3rdparty/jitterentropy-rngd
+       url = https://github.com/smuellerDD/jitterentropy-rngd.git
diff --git a/3rdparty/jitterentropy-rngd b/3rdparty/jitterentropy-rngd
new file mode 160000 (submodule)
index 0000000..ad4d636
--- /dev/null
@@ -0,0 +1 @@
+Subproject commit ad4d6364279fa437a433bbc49d851e35b8dc467d
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644 (file)
index 0000000..bc9a2f6
--- /dev/null
@@ -0,0 +1,33 @@
+cmake_minimum_required(VERSION 2.6)
+
+PROJECT(urngd)
+INCLUDE(GNUInstallDirs)
+INCLUDE (FindPkgConfig)
+
+SET(URNGD_VERSION 1.0.0)
+SET(JTEN_DIR 3rdparty/jitterentropy-rngd)
+
+FIND_PATH(ubox_include_dir NAMES libubox/usock.h)
+FIND_LIBRARY(ubox NAMES ubox)
+INCLUDE_DIRECTORIES(${ubox_include_dir} ${JTEN_DIR})
+
+SET(CMAKE_C_FLAGS_DEBUG -DURNGD_DEBUG)
+
+ADD_DEFINITIONS(-Wall -Werror -Wextra --std=gnu99  -DURNGD_VERSION="${URNGD_VERSION}")
+ADD_DEFINITIONS(-Wno-unused-parameter)
+
+ADD_EXECUTABLE(urngd
+       urngd.c
+       ${JTEN_DIR}/jitterentropy-base.c
+)
+TARGET_LINK_LIBRARIES(urngd ${ubox})
+
+# jitter RNG must not be compiled with optimizations
+SET_SOURCE_FILES_PROPERTIES(${JTEN_DIR}/jitterentropy-base.c PROPERTIES COMPILE_FLAGS -O0)
+
+INSTALL(TARGETS urngd RUNTIME DESTINATION ${CMAKE_INSTALL_SBINDIR})
+
+SET(REMOTE_ADDR 192.168.1.20)
+ADD_CUSTOM_TARGET(upload
+       COMMAND scp ${CMAKE_BINARY_DIR}/urngd root@${REMOTE_ADDR}:/usr/sbin
+)
diff --git a/Makefile b/Makefile
new file mode 100644 (file)
index 0000000..86ffae7
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,36 @@
+CC ?= gcc
+CXX ?= g++
+CMAKE ?= cmake
+CMAKE_BUILD_TYPE ?= Release
+
+define build_cross
+       -rm -fr build-$(2)
+       mkdir build-$(2)
+       cd build-$(2) && \
+               $(CMAKE) \
+                       -D CMAKE_BUILD_TYPE=$(CMAKE_BUILD_TYPE) \
+                       -D CMAKE_TOOLCHAIN_FILE=cmake/$(1)-$(2).cmake \
+                       ..
+       make -j$$((nproc+1)) VERBOSE=$(VERBOSE) -C build-$(2)
+endef
+
+.PHONY: imx6 ath79
+
+all:
+       -rm -fr build
+       mkdir build
+       cd build && CC=$(CC) CXX=$(CXX) $(CMAKE) \
+               -D CMAKE_BUILD_TYPE=$(CMAKE_BUILD_TYPE) \
+               ..
+       make -j$$((nproc+1)) VERBOSE=$(VERBOSE) -C build
+
+imx6:
+       $(call build_cross,openwrt-toolchain,$@)
+
+ath79:
+       $(call build_cross,openwrt-toolchain,$@)
+
+clean:
+       @-rm -fr build*
+
+-include local.mk
diff --git a/README.md b/README.md
new file mode 100644 (file)
index 0000000..c7cf2d1
--- /dev/null
+++ b/README.md
@@ -0,0 +1,13 @@
+μrngd
+=====
+
+μrngd is OpenWrt's micro non-physical true random number generator based on
+timing jitter.
+
+Using the Jitter RNG core, the rngd provides an entropy source that feeds into
+the Linux /dev/random device if its entropy runs low. It updates the /dev/random
+entropy estimator such that the newly provided entropy unblocks /dev/random.
+
+The seeding of /dev/random also ensures that /dev/urandom benefits from entropy.
+Especially during boot time, when the entropy of Linux is low, the Jitter RNGd
+provides a source of sufficient entropy.
diff --git a/cmake/openwrt-toolchain-ath79.cmake b/cmake/openwrt-toolchain-ath79.cmake
new file mode 100644 (file)
index 0000000..411ffd3
--- /dev/null
@@ -0,0 +1,20 @@
+SET(CMAKE_SYSTEM_NAME Linux)
+
+SET(OWRT_STAGING_DIR /opt/devel/openwrt/openwrt.git/staging_dir)
+SET(OWRT_TARGET target-mips_24kc_musl)
+SET(OWRT_TOOLCHAIN toolchain-mips_24kc_gcc-7.4.0_musl)
+SET(OWRT_CROSS ${OWRT_STAGING_DIR}/${OWRT_TOOLCHAIN}/bin/mips-openwrt-linux-)
+
+SET(CMAKE_C_COMPILER ${OWRT_CROSS}gcc)
+SET(CMAKE_CXX_COMPILER ${OWRT_CROSS}g++)
+
+SET(CMAKE_FIND_ROOT_PATH ${OWRT_STAGING_DIR}/${OWRT_TARGET})
+
+SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+
+ADD_DEFINITIONS(
+       -Os -pipe -mno-branch-likely -mips32r2 -mtune=24kc -fno-caller-saves -fno-plt
+       -fhonour-copts -msoft-float -mips16 -minterlink-mips16
+)
diff --git a/cmake/openwrt-toolchain-imx6.cmake b/cmake/openwrt-toolchain-imx6.cmake
new file mode 100644 (file)
index 0000000..32ce656
--- /dev/null
@@ -0,0 +1,17 @@
+SET(CMAKE_SYSTEM_NAME Linux)
+
+SET(OWRT_STAGING_DIR /opt/devel/openwrt/openwrt.git/staging_dir)
+SET(OWRT_TARGET target-arm_cortex-a9+neon_musl_eabi)
+SET(OWRT_TOOLCHAIN toolchain-arm_cortex-a9+neon_gcc-7.4.0_musl_eabi)
+SET(OWRT_CROSS ${OWRT_STAGING_DIR}/${OWRT_TOOLCHAIN}/bin/arm-openwrt-linux-)
+
+SET(CMAKE_C_COMPILER ${OWRT_CROSS}gcc)
+SET(CMAKE_CXX_COMPILER ${OWRT_CROSS}g++)
+
+SET(CMAKE_FIND_ROOT_PATH ${OWRT_STAGING_DIR}/${OWRT_TARGET})
+
+SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+
+ADD_DEFINITIONS(-mcpu=cortex-a9 -mfpu=neon -g3 -fno-caller-saves -fhonour-copts -mfloat-abi=hard)
diff --git a/log.h b/log.h
new file mode 100644 (file)
index 0000000..b434001
--- /dev/null
+++ b/log.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program 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 General Public License for more details.
+ */
+
+#ifndef __LOG_H
+#define __LOG_H
+
+#include <libubox/ulog.h>
+
+#ifdef URNGD_DEBUG
+#define DEBUG(level, fmt, ...) do { \
+       if (debug >= level) { \
+               ulog(LOG_DEBUG, fmt, ## __VA_ARGS__); \
+       } } while (0)
+#else
+#define DEBUG(level, fmt, ...)
+#endif
+
+#define LOG   ULOG_INFO
+#define ERROR ULOG_ERR
+
+extern unsigned int debug;
+
+#endif
diff --git a/urngd.c b/urngd.c
new file mode 100644 (file)
index 0000000..8b9a762
--- /dev/null
+++ b/urngd.c
@@ -0,0 +1,243 @@
+/*
+ * Non-physical true random number generator based on timing jitter.
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ * Copyright Petr Štetiar <ynezz@true.cz>, 2019
+ *
+ * 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, and the entire permission notice in its entirety,
+ *    including the disclaimer of warranties.
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions.  (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR 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 NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+#include <linux/random.h>
+
+#include <libubox/uloop.h>
+
+#include "log.h"
+#include "jitterentropy.h"
+
+#define ENTROPYBYTES 32
+#define ENTROPYTHRESH 1024
+#define OVERSAMPLINGFACTOR 2
+#define DEV_RANDOM "/dev/random"
+#define ENTROPYAVAIL "/proc/sys/kernel/random/entropy_avail"
+#define ENTROPYPOOLBYTES (sizeof(struct rand_pool_info) + \
+               (ENTROPYBYTES * OVERSAMPLINGFACTOR * sizeof(char)))
+
+#ifdef URNGD_DEBUG
+unsigned int debug;
+#endif
+
+struct urngd {
+       struct uloop_fd rnd_fd;
+       struct rand_data *ec;
+       struct rand_pool_info *rpi;
+};
+
+static struct urngd urngd_service;
+
+static inline void memset_secure(void *s, int c, size_t n)
+{
+       memset(s, c, n);
+       __asm__ __volatile__("" : : "r" (s) : "memory");
+}
+
+static size_t write_entropy(struct urngd *u, char *buf, size_t len,
+                           size_t entropy_bytes)
+{
+       int ret;
+       size_t written = 0;
+
+       /* value is in bits */
+       u->rpi->entropy_count = (entropy_bytes * 8);
+       u->rpi->buf_size = len;
+       memcpy(u->rpi->buf, buf, len);
+       memset(buf, 0, len);
+
+       ret =  ioctl(u->rnd_fd.fd, RNDADDENTROPY, u->rpi);
+       if (0 > ret) {
+               ERROR("error injecting entropy: %s\n", strerror(errno));
+       } else {
+               DEBUG(1, "injected %ub (%ub of entropy)\n", len, entropy_bytes);
+               written = len;
+       }
+
+       u->rpi->entropy_count = 0;
+       u->rpi->buf_size = 0;
+       memset(u->rpi->buf, 0, len);
+
+       return written;
+}
+
+static size_t gather_entropy(struct urngd *u)
+{
+       size_t ret = 0;
+       char buf[(ENTROPYBYTES * OVERSAMPLINGFACTOR)];
+
+       if (jent_read_entropy(u->ec, buf, sizeof(buf)) < 0) {
+               ERROR("cannot read entropy\n");
+               return 0;
+       }
+
+       ret = write_entropy(u, buf, sizeof(buf), ENTROPYBYTES);
+       if (sizeof(buf) != ret) {
+               ERROR("injected %lub of entropy, less then %db expected\n",
+                     ret, sizeof(buf));
+       } else {
+               ret = sizeof(buf);
+       }
+
+       memset_secure(buf, 0, sizeof(buf));
+       DEBUG(2, DEV_RANDOM " fed with %lub of entropy\n", ret);
+
+       return ret;
+}
+
+static void low_entropy_cb(struct uloop_fd *ufd, unsigned int events)
+{
+       struct urngd *u = container_of(ufd, struct urngd, rnd_fd);
+
+       DEBUG(2, DEV_RANDOM " signals low entropy\n");
+       gather_entropy(u);
+}
+
+static void urngd_done(struct urngd *u)
+{
+       if (u->ec) {
+               jent_entropy_collector_free(u->ec);
+               u->ec = NULL;
+       }
+
+       if (u->rpi) {
+               memset(u->rpi, 0, ENTROPYPOOLBYTES);
+               free(u->rpi);
+               u->rpi = NULL;
+       }
+
+       if (u->rnd_fd.fd) {
+               close(u->rnd_fd.fd);
+               u->rnd_fd.fd = 0;
+       }
+}
+
+static bool urngd_init(struct urngd *u)
+{
+       int ret = jent_entropy_init();
+       if (ret) {
+               ERROR("jent-rng init failed, err: %d\n", ret);
+               return false;
+       }
+
+       u->ec = jent_entropy_collector_alloc(1, 0);
+       if (!u->ec) {
+               ERROR("jent-rng alloc failed\n");
+               return false;
+       }
+
+       u->rpi = malloc(ENTROPYPOOLBYTES);
+       if (!u->rpi) {
+               ERROR("rand pool alloc failed\n");
+               return false;
+       }
+
+       u->rnd_fd.cb = low_entropy_cb;
+       u->rnd_fd.fd = open(DEV_RANDOM, O_WRONLY);
+       if (u->rnd_fd.fd < 1) {
+               ERROR(DEV_RANDOM " open failed: %s", strerror(errno));
+               return false;
+       }
+
+       uloop_fd_add(&u->rnd_fd, ULOOP_READ);
+
+       return true;
+}
+
+static int usage(const char *prog)
+{
+       fprintf(stderr, "Usage: %s [options]\n"
+               "Options:\n"
+#ifdef URNGD_DEBUG
+               "       -d <level>      Enable debug messages\n"
+#endif
+               "       -S              Print messages to stdout\n"
+               "\n", prog);
+       return 1;
+}
+
+int main(int argc, char **argv)
+{
+       int ch;
+       int ulog_channels = ULOG_KMSG;
+#ifdef URNGD_DEBUG
+       char *dbglvl = getenv("DBGLVL");
+
+       if (dbglvl) {
+               debug = atoi(dbglvl);
+               unsetenv("DBGLVL");
+       }
+#endif
+
+       while ((ch = getopt(argc, argv, "d:S")) != -1) {
+               switch (ch) {
+#ifdef URNGD_DEBUG
+               case 'd':
+                       debug = atoi(optarg);
+                       break;
+#endif
+               case 'S':
+                       ulog_channels = ULOG_STDIO;
+                       break;
+               default:
+                       return usage(argv[0]);
+               }
+       }
+
+       if (!urngd_init(&urngd_service))
+               return -1;
+
+       ulog_open(ulog_channels, LOG_DAEMON, "urngd");
+       LOG("v%s started.\n", URNGD_VERSION);
+
+       gather_entropy(&urngd_service);
+
+       uloop_init();
+       uloop_run();
+       uloop_done();
+
+       urngd_done(&urngd_service);
+
+       return 0;
+}