From 36f885506299cb08f85cf686153e874d9e737344 Mon Sep 17 00:00:00 2001 From: Rob Austein Date: Wed, 3 Dec 2014 13:35:43 +0100 Subject: Initial HAL for Noven entropy interface. Compiles on MacOSX, not yet tested with real hardware. --- src/cryptech_novena_i2c_entropy.c | 489 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 489 insertions(+) create mode 100644 src/cryptech_novena_i2c_entropy.c diff --git a/src/cryptech_novena_i2c_entropy.c b/src/cryptech_novena_i2c_entropy.c new file mode 100644 index 0000000..226ad1a --- /dev/null +++ b/src/cryptech_novena_i2c_entropy.c @@ -0,0 +1,489 @@ +/* + * cryptech_novena_i2c_entropy.c + * ------------------------------ + * + * This is an early prototype Hardware Adaption Layer (HAL) for using + * Cryptlib with the Cryptech project's FGPA cores over an I2C bus on + * the Novena PVT1 development board using the "coretest" byte stream + * protocol. This is compatible with the test/novena_entropy FPGA build. + * + * The communication channel used here is not suitable for production + * use, this is just a prototype. + * + * Authors: Joachim Strömbergson, Paul Selkirk, Rob Austein + * Copyright (c) 2014, SUNET + * + * 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 COPYRIGHT HOLDERS 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 + * COPYRIGHT OWNER 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. + * + * The HAL framework is taken from the Cryptlib hw_dummy.c template, + * and is Copyright 1998-2009 by Peter Gutmann. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#if defined( INC_ALL ) + #include "crypt.h" + #include "context.h" + #include "hardware.h" +#else + #include "crypt.h" + #include "context/context.h" + #include "device/hardware.h" +#endif /* Compiler-specific includes */ + +/* + * I2C_SLAVE comes from /usr/include/linux/i2c-dev.h, but if we + * include that we won't be able to compile this except on Linux. It + * won't *run* anywhere but on Linux, but it's useful to be able to do + * compilation tests on other platforms, eg, with Clang, so for now we + * take the small risk that this one magic constant might change. + */ + +#define I2C_SLAVE 0x0703 + + +#ifdef USE_HARDWARE + +/* + * I2C-related parameters, copied from hash_tester.c + */ + +/* I2C configuration */ +#define I2C_DEV "/dev/i2c-2" +#define I2C_ADDR 0x0f + +/* command codes */ +#define SOC 0x55 +#define EOC 0xaa +#define READ_CMD 0x10 +#define WRITE_CMD 0x11 +#define RESET_CMD 0x01 + +/* response codes */ +#define SOR 0xaa +#define EOR 0x55 +#define READ_OK 0x7f +#define WRITE_OK 0x7e +#define RESET_OK 0x7d +#define UNKNOWN 0xfe +#define ERROR 0xfd + +/* addresses and codes common to all cores */ +#define ADDR_NAME0 0x00 +#define ADDR_NAME1 0x01 +#define ADDR_VERSION 0x02 +#define ADDR_CTRL 0x08 +#define CTRL_INIT_CMD 1 +#define CTRL_NEXT_CMD 2 +#define ADDR_STATUS 0x09 +#define STATUS_READY_BIT 0 +#define STATUS_VALID_BIT 1 + +/* + * Address for reading 32 bits of entropy from the noise board. + * ENTROPY_VALID is nonzero if there's valid entropy available. + */ + +#define ENTROPY_PREFIX 0x20 +#define ENTROPY_ADDR 0x20 +#define ENTROPY_VALID 0x11 + +static int i2cfd = -1; +static int debug = 0; + +/* + * I2C low-level code + */ + +static int i2c_open(void) +{ + if (i2cfd >= 0) + return 1; + + i2cfd = open(I2C_DEV, O_RDWR); + + if (i2cfd < 0) { + perror("Unable to open " I2C_DEV); + i2cfd = -1; + return 0; + } + + if (ioctl(i2cfd, I2C_SLAVE, I2C_ADDR) < 0) { + perror("Unable to set i2c slave device"); + return 0; + } + + if (debug) + fprintf(stderr, "[ Opened %s, fd %d ]\n", I2C_DEV, i2cfd); + + return 1; +} + +static int i2c_write_bytes(const unsigned char *buf, const size_t len) +{ + if (debug) { + int i; + fprintf(stderr, "write ["); + for (i = 0; i < len; ++i) + fprintf(stderr, " %02x", buf[i]); + fprintf(stderr, " ]\n"); + } + + if (!i2c_open()) + return 0; + + if (write(i2cfd, buf, len) != len) { + perror("i2c write failed"); + return 0; + } + + return 1; +} + + +static int i2c_read_byte(unsigned char *b) +{ + /* + * read() on the i2c device only returns one byte at a time, + * and we need to parse the response one byte at a time anyway. + */ + + if (!i2c_open()) + return 0; + + if (read(i2cfd, b, 1) != 1) { + perror("i2c read failed"); + return 0; + } + + return 1; +} + +static int i2c_send_write_cmd(const unsigned char addr0, const unsigned char addr1, const unsigned char data[]) +{ + unsigned char buf[9]; + + buf[0] = SOC; + buf[1] = WRITE_CMD; + buf[2] = addr0; + buf[3] = addr1; + buf[4] = data[0]; + buf[5] = data[1]; + buf[6] = data[2]; + buf[7] = data[3]; + buf[8] = EOC; + + return i2c_write_bytes(buf, sizeof(buf)); +} + +static int i2c_send_read_cmd(const unsigned char addr0, const unsigned char addr1) +{ + unsigned char buf[5]; + + buf[0] = SOC; + buf[1] = READ_CMD; + buf[2] = addr0; + buf[3] = addr1; + buf[4] = EOC; + + return i2c_write_bytes(buf, sizeof(buf)); +} + +static int i2c_get_resp(unsigned char *buf, const size_t length) +{ + int i, len = length; + + for (i = 0; i < len; ++i) { + assert(len <= length); /* Paranoia */ + + if (!i2c_read_byte(&buf[i])) + return 0; + + switch (i) { /* Special handling for certain positions in response */ + + case 0: + if (buf[i] == SOR) /* Start of record (we hope) */ + continue; + fprintf(stderr, "Lost sync: expected 0x%02x (SOR), got 0x%02x\n", SOR, buf[0]); + return 0; + + case 1: /* Response code */ + switch (buf[i]) { + case READ_OK: + len = 9; + continue; + case WRITE_OK: + len = 5; + continue; + case RESET_OK: + len = 3; + continue; + case ERROR: + case UNKNOWN: + len = 4; + continue; + default: + fprintf(stderr, "Lost sync: unknown response code 0x%02x\n", buf[i]); + return 0; + } + } + } + + if (debug) { + fprintf(stderr, "read ["); + for (i = 0; i < len; ++i) + fprintf(stderr, " %02x", buf[i]); + fprintf(stderr, " ]\n"); + } + + return 1; +} + +static int i2c_check_expected(const unsigned char buf[], const int i, const unsigned char expected) +{ + if (buf[i] == expected) + return 1; + fprintf(stderr, "Response byte %d: expected 0x%02x, got 0x%02x\n", i, expected, buf[i]); + return 0; +} + + +static int i2c_write(const unsigned char addr0, const unsigned char addr1, const unsigned char data[]) +{ + unsigned char buf[5]; + + if (!i2c_send_write_cmd(addr0, addr1, data) || + !i2c_get_resp(buf, sizeof(buf)) || + !i2c_check_expected(buf, 0, SOR) || + !i2c_check_expected(buf, 1, WRITE_OK) || + !i2c_check_expected(buf, 2, addr0) || + !i2c_check_expected(buf, 3, addr1) || + !i2c_check_expected(buf, 4, EOR)) + return 0; + + return 1; +} + +static int i2c_read(const unsigned char addr0, const unsigned char addr1, unsigned char data[]) +{ + unsigned char buf[9]; + + if (!i2c_send_read_cmd(addr0, addr1) || + !i2c_get_resp(buf, sizeof(buf)) || + !i2c_check_expected(buf, 0, SOR) || + !i2c_check_expected(buf, 1, READ_OK) || + !i2c_check_expected(buf, 2, addr0) || + !i2c_check_expected(buf, 3, addr1) || + !i2c_check_expected(buf, 8, EOR)) + return 0; + + data[0] = buf[4]; + data[1] = buf[5]; + data[2] = buf[6]; + data[3] = buf[7]; + return 1; +} + +static int i2c_ctrl(const unsigned char addr0, const unsigned char ctrl_cmd) +{ + unsigned char data[4]; + memset(data, 0, sizeof(data)); + data[3] = ctrl_cmd; + return i2c_write(addr0, ADDR_CTRL, data); +} + +static int i2c_wait(const unsigned char addr0, const unsigned char status) +{ + unsigned char buf[9]; + + do { + if (!i2c_send_read_cmd(addr0, ADDR_STATUS)) + return 0; + if (!i2c_get_resp(buf, sizeof(buf))) + return 0; + if (buf[1] != READ_OK) + return 0; + } while ((buf[7] & status) != status); + + if (debug) + fprintf(stderr, "[ Done waiting ]\n"); + + return 1; +} + +static int i2c_wait_ready(const unsigned char addr0) +{ + if (debug) + fprintf(stderr, "[ Waiting for ready ]\n"); + return i2c_wait(addr0, STATUS_READY_BIT); +} + +static int i2c_wait_valid(const unsigned char addr0) +{ + if (debug) + fprintf(stderr, "[ Waiting for valid ]\n"); + return i2c_wait(addr0, STATUS_VALID_BIT); +} + +/**************************************************************************** + * * + * Random Numbers * + * * + ****************************************************************************/ + +/* + * First attempt at reading random data from the Novena. + * Not sure what we should do if ENTROPY_VALID isn't lit, spin wait? + */ + +static int readRandom(void *buffer, const int length) +{ + unsigned char temp[4], *buf = buffer; + int i, last; + + assert(isWritePtr(buffer, length)); + + REQUIRES_B(length >= 1 && length < MAX_INTLENGTH); + + for (i = 0; i < length; i += 4) { + if (!i2c_wait_valid(ENTROPY_PREFIX)) { + fprintf(stderr, "[ i2c_wait_valid(ENTROPY_PREFIX) failed ]\n"); + return 0; + } + do { + if (!i2c_read(ENTROPY_PREFIX, ENTROPY_VALID, temp)) { + fprintf(stderr, "[ i2c_read(ENTROPY_VALID) failed ]\n"); + return 0; + } + } while (!temp[3]); + if (!i2c_wait_valid(ENTROPY_PREFIX)) { + fprintf(stderr, "[ i2c_wait_valid(ENTROPY_PREFIX) failed ]\n"); + return 0; + } + last = (length - i) < 4; + if (!i2c_read(ENTROPY_PREFIX, ENTROPY_ADDR, last ? temp : buf + i)) { + fprintf(stderr, "[ i2c_read(ENTROPY_ADDR) failed ]\n"); + return 0; + } + if (last) { + for (; i < length; i++) + buf[i] = temp[i & i]; + } + } + + return 1; +} + +/**************************************************************************** + * * + * Hardware External Interface * + * * + ****************************************************************************/ + +/* The capability information for this device */ + +static const CAPABILITY_INFO capabilities[] = { + { CRYPT_ALGO_NONE }, { CRYPT_ALGO_NONE } +}; + +/* Return the hardware capabilities list */ + +int hwGetCapabilities(const CAPABILITY_INFO **capabilityInfo, int *noCapabilities) +{ + assert(isReadPtr(capabilityInfo, sizeof(CAPABILITY_INFO *))); + assert(isWritePtr(noCapabilities, sizeof(int))); + + *capabilityInfo = capabilities; + *noCapabilities = FAILSAFE_ARRAYSIZE(capabilities, CAPABILITY_INFO); + + return CRYPT_OK; +} + +/* Get random data from the hardware. */ + +int hwGetRandom(void *buffer, const int length) +{ + assert(isWritePtr(buffer, length)); + + REQUIRES(length >= 1 && length < MAX_INTLENGTH); + + if (readRandom(buffer, length)) + return CRYPT_OK; + else + return CRYPT_ERROR_RANDOM; +} + +/* + * These "personality" methods are trivial stubs, as we do not yet + * have any cores which do encyrption or signature. When we do, these + * methods will need to be rewritten, and whoever does that rewriting + * will definitely want to look at the detailed comments and template + * code in device/hw_dummy.c. + */ + +/* Look up an item held in the hardware */ + +int hwLookupItem(const void *keyID, const int keyIDlength, int *keyHandle) +{ + assert(keyHandle != NULL); + *keyHandle = CRYPT_ERROR; + return CRYPT_ERROR_NOTFOUND; +} + +/* Delete an item held in the hardware */ + +int hwDeleteItem(const int keyHandle) +{ + return CRYPT_OK; +} + +/* Initialise/zeroise the hardware */ + +int hwInitialise(void) +{ + return CRYPT_OK; +} + +#endif /* USE_HARDWARE */ + +/* + * "Any programmer who fails to comply with the standard naming, formatting, + * or commenting conventions should be shot. If it so happens that it is + * inconvenient to shoot him, then he is to be politely requested to recode + * his program in adherence to the above standard." + * -- Michael Spier, Digital Equipment Corporation + * + * Local variables: + * indent-tabs-mode: nil + * End: + */ -- cgit v1.2.3