mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-05 11:00:15 +00:00
185f812c41
Sphinx expects Return: and not @return to indicate a return value. find . -name '*.c' -exec \ sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \; find . -name '*.h' -exec \ sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \; Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
361 lines
9.1 KiB
C
361 lines
9.1 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Copyright (c) 2013, Google Inc.
|
|
*/
|
|
|
|
#ifndef USE_HOSTCC
|
|
#include <common.h>
|
|
#include <fdtdec.h>
|
|
#include <log.h>
|
|
#include <asm/types.h>
|
|
#include <asm/byteorder.h>
|
|
#include <linux/errno.h>
|
|
#include <asm/types.h>
|
|
#include <asm/unaligned.h>
|
|
#else
|
|
#include "fdt_host.h"
|
|
#include "mkimage.h"
|
|
#include <fdt_support.h>
|
|
#endif
|
|
#include <u-boot/rsa.h>
|
|
#include <u-boot/rsa-mod-exp.h>
|
|
|
|
#define UINT64_MULT32(v, multby) (((uint64_t)(v)) * ((uint32_t)(multby)))
|
|
|
|
#define get_unaligned_be32(a) fdt32_to_cpu(*(uint32_t *)a)
|
|
#define put_unaligned_be32(a, b) (*(uint32_t *)(b) = cpu_to_fdt32(a))
|
|
|
|
static inline uint64_t fdt64_to_cpup(const void *p)
|
|
{
|
|
fdt64_t w;
|
|
|
|
memcpy(&w, p, sizeof(w));
|
|
return fdt64_to_cpu(w);
|
|
}
|
|
|
|
/* Default public exponent for backward compatibility */
|
|
#define RSA_DEFAULT_PUBEXP 65537
|
|
|
|
/**
|
|
* subtract_modulus() - subtract modulus from the given value
|
|
*
|
|
* @key: Key containing modulus to subtract
|
|
* @num: Number to subtract modulus from, as little endian word array
|
|
*/
|
|
static void subtract_modulus(const struct rsa_public_key *key, uint32_t num[])
|
|
{
|
|
int64_t acc = 0;
|
|
uint i;
|
|
|
|
for (i = 0; i < key->len; i++) {
|
|
acc += (uint64_t)num[i] - key->modulus[i];
|
|
num[i] = (uint32_t)acc;
|
|
acc >>= 32;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* greater_equal_modulus() - check if a value is >= modulus
|
|
*
|
|
* @key: Key containing modulus to check
|
|
* @num: Number to check against modulus, as little endian word array
|
|
* Return: 0 if num < modulus, 1 if num >= modulus
|
|
*/
|
|
static int greater_equal_modulus(const struct rsa_public_key *key,
|
|
uint32_t num[])
|
|
{
|
|
int i;
|
|
|
|
for (i = (int)key->len - 1; i >= 0; i--) {
|
|
if (num[i] < key->modulus[i])
|
|
return 0;
|
|
if (num[i] > key->modulus[i])
|
|
return 1;
|
|
}
|
|
|
|
return 1; /* equal */
|
|
}
|
|
|
|
/**
|
|
* montgomery_mul_add_step() - Perform montgomery multiply-add step
|
|
*
|
|
* Operation: montgomery result[] += a * b[] / n0inv % modulus
|
|
*
|
|
* @key: RSA key
|
|
* @result: Place to put result, as little endian word array
|
|
* @a: Multiplier
|
|
* @b: Multiplicand, as little endian word array
|
|
*/
|
|
static void montgomery_mul_add_step(const struct rsa_public_key *key,
|
|
uint32_t result[], const uint32_t a, const uint32_t b[])
|
|
{
|
|
uint64_t acc_a, acc_b;
|
|
uint32_t d0;
|
|
uint i;
|
|
|
|
acc_a = (uint64_t)a * b[0] + result[0];
|
|
d0 = (uint32_t)acc_a * key->n0inv;
|
|
acc_b = (uint64_t)d0 * key->modulus[0] + (uint32_t)acc_a;
|
|
for (i = 1; i < key->len; i++) {
|
|
acc_a = (acc_a >> 32) + (uint64_t)a * b[i] + result[i];
|
|
acc_b = (acc_b >> 32) + (uint64_t)d0 * key->modulus[i] +
|
|
(uint32_t)acc_a;
|
|
result[i - 1] = (uint32_t)acc_b;
|
|
}
|
|
|
|
acc_a = (acc_a >> 32) + (acc_b >> 32);
|
|
|
|
result[i - 1] = (uint32_t)acc_a;
|
|
|
|
if (acc_a >> 32)
|
|
subtract_modulus(key, result);
|
|
}
|
|
|
|
/**
|
|
* montgomery_mul() - Perform montgomery mutitply
|
|
*
|
|
* Operation: montgomery result[] = a[] * b[] / n0inv % modulus
|
|
*
|
|
* @key: RSA key
|
|
* @result: Place to put result, as little endian word array
|
|
* @a: Multiplier, as little endian word array
|
|
* @b: Multiplicand, as little endian word array
|
|
*/
|
|
static void montgomery_mul(const struct rsa_public_key *key,
|
|
uint32_t result[], uint32_t a[], const uint32_t b[])
|
|
{
|
|
uint i;
|
|
|
|
for (i = 0; i < key->len; ++i)
|
|
result[i] = 0;
|
|
for (i = 0; i < key->len; ++i)
|
|
montgomery_mul_add_step(key, result, a[i], b);
|
|
}
|
|
|
|
/**
|
|
* num_pub_exponent_bits() - Number of bits in the public exponent
|
|
*
|
|
* @key: RSA key
|
|
* @num_bits: Storage for the number of public exponent bits
|
|
*/
|
|
static int num_public_exponent_bits(const struct rsa_public_key *key,
|
|
int *num_bits)
|
|
{
|
|
uint64_t exponent;
|
|
int exponent_bits;
|
|
const uint max_bits = (sizeof(exponent) * 8);
|
|
|
|
exponent = key->exponent;
|
|
exponent_bits = 0;
|
|
|
|
if (!exponent) {
|
|
*num_bits = exponent_bits;
|
|
return 0;
|
|
}
|
|
|
|
for (exponent_bits = 1; exponent_bits < max_bits + 1; ++exponent_bits)
|
|
if (!(exponent >>= 1)) {
|
|
*num_bits = exponent_bits;
|
|
return 0;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* is_public_exponent_bit_set() - Check if a bit in the public exponent is set
|
|
*
|
|
* @key: RSA key
|
|
* @pos: The bit position to check
|
|
*/
|
|
static int is_public_exponent_bit_set(const struct rsa_public_key *key,
|
|
int pos)
|
|
{
|
|
return key->exponent & (1ULL << pos);
|
|
}
|
|
|
|
/**
|
|
* pow_mod() - in-place public exponentiation
|
|
*
|
|
* @key: RSA key
|
|
* @inout: Big-endian word array containing value and result
|
|
*/
|
|
static int pow_mod(const struct rsa_public_key *key, uint32_t *inout)
|
|
{
|
|
uint32_t *result, *ptr;
|
|
uint i;
|
|
int j, k;
|
|
|
|
/* Sanity check for stack size - key->len is in 32-bit words */
|
|
if (key->len > RSA_MAX_KEY_BITS / 32) {
|
|
debug("RSA key words %u exceeds maximum %d\n", key->len,
|
|
RSA_MAX_KEY_BITS / 32);
|
|
return -EINVAL;
|
|
}
|
|
|
|
uint32_t val[key->len], acc[key->len], tmp[key->len];
|
|
uint32_t a_scaled[key->len];
|
|
result = tmp; /* Re-use location. */
|
|
|
|
/* Convert from big endian byte array to little endian word array. */
|
|
for (i = 0, ptr = inout + key->len - 1; i < key->len; i++, ptr--)
|
|
val[i] = get_unaligned_be32(ptr);
|
|
|
|
if (0 != num_public_exponent_bits(key, &k))
|
|
return -EINVAL;
|
|
|
|
if (k < 2) {
|
|
debug("Public exponent is too short (%d bits, minimum 2)\n",
|
|
k);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!is_public_exponent_bit_set(key, 0)) {
|
|
debug("LSB of RSA public exponent must be set.\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* the bit at e[k-1] is 1 by definition, so start with: C := M */
|
|
montgomery_mul(key, acc, val, key->rr); /* acc = a * RR / R mod n */
|
|
/* retain scaled version for intermediate use */
|
|
memcpy(a_scaled, acc, key->len * sizeof(a_scaled[0]));
|
|
|
|
for (j = k - 2; j > 0; --j) {
|
|
montgomery_mul(key, tmp, acc, acc); /* tmp = acc^2 / R mod n */
|
|
|
|
if (is_public_exponent_bit_set(key, j)) {
|
|
/* acc = tmp * val / R mod n */
|
|
montgomery_mul(key, acc, tmp, a_scaled);
|
|
} else {
|
|
/* e[j] == 0, copy tmp back to acc for next operation */
|
|
memcpy(acc, tmp, key->len * sizeof(acc[0]));
|
|
}
|
|
}
|
|
|
|
/* the bit at e[0] is always 1 */
|
|
montgomery_mul(key, tmp, acc, acc); /* tmp = acc^2 / R mod n */
|
|
montgomery_mul(key, acc, tmp, val); /* acc = tmp * a / R mod M */
|
|
memcpy(result, acc, key->len * sizeof(result[0]));
|
|
|
|
/* Make sure result < mod; result is at most 1x mod too large. */
|
|
if (greater_equal_modulus(key, result))
|
|
subtract_modulus(key, result);
|
|
|
|
/* Convert to bigendian byte array */
|
|
for (i = key->len - 1, ptr = inout; (int)i >= 0; i--, ptr++)
|
|
put_unaligned_be32(result[i], ptr);
|
|
return 0;
|
|
}
|
|
|
|
static void rsa_convert_big_endian(uint32_t *dst, const uint32_t *src, int len)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < len; i++)
|
|
dst[i] = fdt32_to_cpu(src[len - 1 - i]);
|
|
}
|
|
|
|
int rsa_mod_exp_sw(const uint8_t *sig, uint32_t sig_len,
|
|
struct key_prop *prop, uint8_t *out)
|
|
{
|
|
struct rsa_public_key key;
|
|
int ret;
|
|
|
|
if (!prop) {
|
|
debug("%s: Skipping invalid prop", __func__);
|
|
return -EBADF;
|
|
}
|
|
key.n0inv = prop->n0inv;
|
|
key.len = prop->num_bits;
|
|
|
|
if (!prop->public_exponent)
|
|
key.exponent = RSA_DEFAULT_PUBEXP;
|
|
else
|
|
key.exponent = fdt64_to_cpup(prop->public_exponent);
|
|
|
|
if (!key.len || !prop->modulus || !prop->rr) {
|
|
debug("%s: Missing RSA key info", __func__);
|
|
return -EFAULT;
|
|
}
|
|
|
|
/* Sanity check for stack size */
|
|
if (key.len > RSA_MAX_KEY_BITS || key.len < RSA_MIN_KEY_BITS) {
|
|
debug("RSA key bits %u outside allowed range %d..%d\n",
|
|
key.len, RSA_MIN_KEY_BITS, RSA_MAX_KEY_BITS);
|
|
return -EFAULT;
|
|
}
|
|
key.len /= sizeof(uint32_t) * 8;
|
|
uint32_t key1[key.len], key2[key.len];
|
|
|
|
key.modulus = key1;
|
|
key.rr = key2;
|
|
rsa_convert_big_endian(key.modulus, (uint32_t *)prop->modulus, key.len);
|
|
rsa_convert_big_endian(key.rr, (uint32_t *)prop->rr, key.len);
|
|
if (!key.modulus || !key.rr) {
|
|
debug("%s: Out of memory", __func__);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
uint32_t buf[sig_len / sizeof(uint32_t)];
|
|
|
|
memcpy(buf, sig, sig_len);
|
|
|
|
ret = pow_mod(&key, buf);
|
|
if (ret)
|
|
return ret;
|
|
|
|
memcpy(out, buf, sig_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#if defined(CONFIG_CMD_ZYNQ_RSA)
|
|
/**
|
|
* zynq_pow_mod - in-place public exponentiation
|
|
*
|
|
* @keyptr: RSA key
|
|
* @inout: Big-endian word array containing value and result
|
|
* Return: 0 on successful calculation, otherwise failure error code
|
|
*
|
|
* FIXME: Use pow_mod() instead of zynq_pow_mod()
|
|
* pow_mod calculation required for zynq is bit different from
|
|
* pw_mod above here, hence defined zynq specific routine.
|
|
*/
|
|
int zynq_pow_mod(uint32_t *keyptr, uint32_t *inout)
|
|
{
|
|
u32 *result, *ptr;
|
|
uint i;
|
|
struct rsa_public_key *key;
|
|
u32 val[RSA2048_BYTES], acc[RSA2048_BYTES], tmp[RSA2048_BYTES];
|
|
|
|
key = (struct rsa_public_key *)keyptr;
|
|
|
|
/* Sanity check for stack size - key->len is in 32-bit words */
|
|
if (key->len > RSA_MAX_KEY_BITS / 32) {
|
|
debug("RSA key words %u exceeds maximum %d\n", key->len,
|
|
RSA_MAX_KEY_BITS / 32);
|
|
return -EINVAL;
|
|
}
|
|
|
|
result = tmp; /* Re-use location. */
|
|
|
|
for (i = 0, ptr = inout; i < key->len; i++, ptr++)
|
|
val[i] = *(ptr);
|
|
|
|
montgomery_mul(key, acc, val, key->rr); /* axx = a * RR / R mod M */
|
|
for (i = 0; i < 16; i += 2) {
|
|
montgomery_mul(key, tmp, acc, acc); /* tmp = acc^2 / R mod M */
|
|
montgomery_mul(key, acc, tmp, tmp); /* acc = tmp^2 / R mod M */
|
|
}
|
|
montgomery_mul(key, result, acc, val); /* result = XX * a / R mod M */
|
|
|
|
/* Make sure result < mod; result is at most 1x mod too large. */
|
|
if (greater_equal_modulus(key, result))
|
|
subtract_modulus(key, result);
|
|
|
|
for (i = 0, ptr = inout; i < key->len; i++, ptr++)
|
|
*ptr = result[i];
|
|
|
|
return 0;
|
|
}
|
|
#endif
|