mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-28 07:31:15 +00:00
8479333ce7
Fixes problem for unaligned 32bit big-endian access in lib/rsa/rsa-keyprop.c. Exchanges br_i32_decode() with get_unaligned_be32(). This will keep the unaligned access for architectures capable and will do some byte-shift magic for the not so capable ones. Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-by: Robert Reither <robert.reither@external.thalesgroup.com> Remove unused include. Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
728 lines
17 KiB
C
728 lines
17 KiB
C
// SPDX-License-Identifier: GPL-2.0+ and MIT
|
|
/*
|
|
* RSA library - generate parameters for a public key
|
|
*
|
|
* Copyright (c) 2019 Linaro Limited
|
|
* Author: AKASHI Takahiro
|
|
*
|
|
* Big number routines in this file come from BearSSL:
|
|
* Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <image.h>
|
|
#include <malloc.h>
|
|
#include <crypto/internal/rsa.h>
|
|
#include <u-boot/rsa-mod-exp.h>
|
|
#include <asm/unaligned.h>
|
|
|
|
/**
|
|
* br_dec16be() - Convert 16-bit big-endian integer to native
|
|
* @src: Pointer to data
|
|
* Return: Native-endian integer
|
|
*/
|
|
static unsigned br_dec16be(const void *src)
|
|
{
|
|
return get_unaligned_be16(src);
|
|
}
|
|
|
|
/**
|
|
* br_dec32be() - Convert 32-bit big-endian integer to native
|
|
* @src: Pointer to data
|
|
* Return: Native-endian integer
|
|
*/
|
|
static uint32_t br_dec32be(const void *src)
|
|
{
|
|
return get_unaligned_be32(src);
|
|
}
|
|
|
|
/**
|
|
* br_enc32be() - Convert native 32-bit integer to big-endian
|
|
* @dst: Pointer to buffer to store big-endian integer in
|
|
* @x: Native 32-bit integer
|
|
*/
|
|
static void br_enc32be(void *dst, uint32_t x)
|
|
{
|
|
__be32 tmp;
|
|
|
|
tmp = cpu_to_be32(x);
|
|
memcpy(dst, &tmp, sizeof(tmp));
|
|
}
|
|
|
|
/* from BearSSL's src/inner.h */
|
|
|
|
/*
|
|
* Negate a boolean.
|
|
*/
|
|
static uint32_t NOT(uint32_t ctl)
|
|
{
|
|
return ctl ^ 1;
|
|
}
|
|
|
|
/*
|
|
* Multiplexer: returns x if ctl == 1, y if ctl == 0.
|
|
*/
|
|
static uint32_t MUX(uint32_t ctl, uint32_t x, uint32_t y)
|
|
{
|
|
return y ^ (-ctl & (x ^ y));
|
|
}
|
|
|
|
/*
|
|
* Equality check: returns 1 if x == y, 0 otherwise.
|
|
*/
|
|
static uint32_t EQ(uint32_t x, uint32_t y)
|
|
{
|
|
uint32_t q;
|
|
|
|
q = x ^ y;
|
|
return NOT((q | -q) >> 31);
|
|
}
|
|
|
|
/*
|
|
* Inequality check: returns 1 if x != y, 0 otherwise.
|
|
*/
|
|
static uint32_t NEQ(uint32_t x, uint32_t y)
|
|
{
|
|
uint32_t q;
|
|
|
|
q = x ^ y;
|
|
return (q | -q) >> 31;
|
|
}
|
|
|
|
/*
|
|
* Comparison: returns 1 if x > y, 0 otherwise.
|
|
*/
|
|
static uint32_t GT(uint32_t x, uint32_t y)
|
|
{
|
|
/*
|
|
* If both x < 2^31 and y < 2^31, then y-x will have its high
|
|
* bit set if x > y, cleared otherwise.
|
|
*
|
|
* If either x >= 2^31 or y >= 2^31 (but not both), then the
|
|
* result is the high bit of x.
|
|
*
|
|
* If both x >= 2^31 and y >= 2^31, then we can virtually
|
|
* subtract 2^31 from both, and we are back to the first case.
|
|
* Since (y-2^31)-(x-2^31) = y-x, the subtraction is already
|
|
* fine.
|
|
*/
|
|
uint32_t z;
|
|
|
|
z = y - x;
|
|
return (z ^ ((x ^ y) & (x ^ z))) >> 31;
|
|
}
|
|
|
|
/*
|
|
* Compute the bit length of a 32-bit integer. Returned value is between 0
|
|
* and 32 (inclusive).
|
|
*/
|
|
static uint32_t BIT_LENGTH(uint32_t x)
|
|
{
|
|
uint32_t k, c;
|
|
|
|
k = NEQ(x, 0);
|
|
c = GT(x, 0xFFFF); x = MUX(c, x >> 16, x); k += c << 4;
|
|
c = GT(x, 0x00FF); x = MUX(c, x >> 8, x); k += c << 3;
|
|
c = GT(x, 0x000F); x = MUX(c, x >> 4, x); k += c << 2;
|
|
c = GT(x, 0x0003); x = MUX(c, x >> 2, x); k += c << 1;
|
|
k += GT(x, 0x0001);
|
|
return k;
|
|
}
|
|
|
|
#define GE(x, y) NOT(GT(y, x))
|
|
#define LT(x, y) GT(y, x)
|
|
#define MUL(x, y) ((uint64_t)(x) * (uint64_t)(y))
|
|
|
|
/*
|
|
* Integers 'i32'
|
|
* --------------
|
|
*
|
|
* The 'i32' functions implement computations on big integers using
|
|
* an internal representation as an array of 32-bit integers. For
|
|
* an array x[]:
|
|
* -- x[0] contains the "announced bit length" of the integer
|
|
* -- x[1], x[2]... contain the value in little-endian order (x[1]
|
|
* contains the least significant 32 bits)
|
|
*
|
|
* Multiplications rely on the elementary 32x32->64 multiplication.
|
|
*
|
|
* The announced bit length specifies the number of bits that are
|
|
* significant in the subsequent 32-bit words. Unused bits in the
|
|
* last (most significant) word are set to 0; subsequent words are
|
|
* uninitialized and need not exist at all.
|
|
*
|
|
* The execution time and memory access patterns of all computations
|
|
* depend on the announced bit length, but not on the actual word
|
|
* values. For modular integers, the announced bit length of any integer
|
|
* modulo n is equal to the actual bit length of n; thus, computations
|
|
* on modular integers are "constant-time" (only the modulus length may
|
|
* leak).
|
|
*/
|
|
|
|
/*
|
|
* Extract one word from an integer. The offset is counted in bits.
|
|
* The word MUST entirely fit within the word elements corresponding
|
|
* to the announced bit length of a[].
|
|
*/
|
|
static uint32_t br_i32_word(const uint32_t *a, uint32_t off)
|
|
{
|
|
size_t u;
|
|
unsigned j;
|
|
|
|
u = (size_t)(off >> 5) + 1;
|
|
j = (unsigned)off & 31;
|
|
if (j == 0) {
|
|
return a[u];
|
|
} else {
|
|
return (a[u] >> j) | (a[u + 1] << (32 - j));
|
|
}
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_bitlen.c */
|
|
|
|
/*
|
|
* Compute the actual bit length of an integer. The argument x should
|
|
* point to the first (least significant) value word of the integer.
|
|
* The len 'xlen' contains the number of 32-bit words to access.
|
|
*
|
|
* CT: value or length of x does not leak.
|
|
*/
|
|
static uint32_t br_i32_bit_length(uint32_t *x, size_t xlen)
|
|
{
|
|
uint32_t tw, twk;
|
|
|
|
tw = 0;
|
|
twk = 0;
|
|
while (xlen -- > 0) {
|
|
uint32_t w, c;
|
|
|
|
c = EQ(tw, 0);
|
|
w = x[xlen];
|
|
tw = MUX(c, w, tw);
|
|
twk = MUX(c, (uint32_t)xlen, twk);
|
|
}
|
|
return (twk << 5) + BIT_LENGTH(tw);
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_decode.c */
|
|
|
|
/*
|
|
* Decode an integer from its big-endian unsigned representation. The
|
|
* "true" bit length of the integer is computed, but all words of x[]
|
|
* corresponding to the full 'len' bytes of the source are set.
|
|
*
|
|
* CT: value or length of x does not leak.
|
|
*/
|
|
static void br_i32_decode(uint32_t *x, const void *src, size_t len)
|
|
{
|
|
const unsigned char *buf;
|
|
size_t u, v;
|
|
|
|
buf = src;
|
|
u = len;
|
|
v = 1;
|
|
for (;;) {
|
|
if (u < 4) {
|
|
uint32_t w;
|
|
|
|
if (u < 2) {
|
|
if (u == 0) {
|
|
break;
|
|
} else {
|
|
w = buf[0];
|
|
}
|
|
} else {
|
|
if (u == 2) {
|
|
w = br_dec16be(buf);
|
|
} else {
|
|
w = ((uint32_t)buf[0] << 16)
|
|
| br_dec16be(buf + 1);
|
|
}
|
|
}
|
|
x[v ++] = w;
|
|
break;
|
|
} else {
|
|
u -= 4;
|
|
x[v ++] = br_dec32be(buf + u);
|
|
}
|
|
}
|
|
x[0] = br_i32_bit_length(x + 1, v - 1);
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_encode.c */
|
|
|
|
/*
|
|
* Encode an integer into its big-endian unsigned representation. The
|
|
* output length in bytes is provided (parameter 'len'); if the length
|
|
* is too short then the integer is appropriately truncated; if it is
|
|
* too long then the extra bytes are set to 0.
|
|
*/
|
|
static void br_i32_encode(void *dst, size_t len, const uint32_t *x)
|
|
{
|
|
unsigned char *buf;
|
|
size_t k;
|
|
|
|
buf = dst;
|
|
|
|
/*
|
|
* Compute the announced size of x in bytes; extra bytes are
|
|
* filled with zeros.
|
|
*/
|
|
k = (x[0] + 7) >> 3;
|
|
while (len > k) {
|
|
*buf ++ = 0;
|
|
len --;
|
|
}
|
|
|
|
/*
|
|
* Now we use k as index within x[]. That index starts at 1;
|
|
* we initialize it to the topmost complete word, and process
|
|
* any remaining incomplete word.
|
|
*/
|
|
k = (len + 3) >> 2;
|
|
switch (len & 3) {
|
|
case 3:
|
|
*buf ++ = x[k] >> 16;
|
|
/* fall through */
|
|
case 2:
|
|
*buf ++ = x[k] >> 8;
|
|
/* fall through */
|
|
case 1:
|
|
*buf ++ = x[k];
|
|
k --;
|
|
}
|
|
|
|
/*
|
|
* Encode all complete words.
|
|
*/
|
|
while (k > 0) {
|
|
br_enc32be(buf, x[k]);
|
|
k --;
|
|
buf += 4;
|
|
}
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_ninv32.c */
|
|
|
|
/*
|
|
* Compute -(1/x) mod 2^32. If x is even, then this function returns 0.
|
|
*/
|
|
static uint32_t br_i32_ninv32(uint32_t x)
|
|
{
|
|
uint32_t y;
|
|
|
|
y = 2 - x;
|
|
y *= 2 - y * x;
|
|
y *= 2 - y * x;
|
|
y *= 2 - y * x;
|
|
y *= 2 - y * x;
|
|
return MUX(x & 1, -y, 0);
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_add.c */
|
|
|
|
/*
|
|
* Add b[] to a[] and return the carry (0 or 1). If ctl is 0, then a[]
|
|
* is unmodified, but the carry is still computed and returned. The
|
|
* arrays a[] and b[] MUST have the same announced bit length.
|
|
*
|
|
* a[] and b[] MAY be the same array, but partial overlap is not allowed.
|
|
*/
|
|
static uint32_t br_i32_add(uint32_t *a, const uint32_t *b, uint32_t ctl)
|
|
{
|
|
uint32_t cc;
|
|
size_t u, m;
|
|
|
|
cc = 0;
|
|
m = (a[0] + 63) >> 5;
|
|
for (u = 1; u < m; u ++) {
|
|
uint32_t aw, bw, naw;
|
|
|
|
aw = a[u];
|
|
bw = b[u];
|
|
naw = aw + bw + cc;
|
|
|
|
/*
|
|
* Carry is 1 if naw < aw. Carry is also 1 if naw == aw
|
|
* AND the carry was already 1.
|
|
*/
|
|
cc = (cc & EQ(naw, aw)) | LT(naw, aw);
|
|
a[u] = MUX(ctl, naw, aw);
|
|
}
|
|
return cc;
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_sub.c */
|
|
|
|
/*
|
|
* Subtract b[] from a[] and return the carry (0 or 1). If ctl is 0,
|
|
* then a[] is unmodified, but the carry is still computed and returned.
|
|
* The arrays a[] and b[] MUST have the same announced bit length.
|
|
*
|
|
* a[] and b[] MAY be the same array, but partial overlap is not allowed.
|
|
*/
|
|
static uint32_t br_i32_sub(uint32_t *a, const uint32_t *b, uint32_t ctl)
|
|
{
|
|
uint32_t cc;
|
|
size_t u, m;
|
|
|
|
cc = 0;
|
|
m = (a[0] + 63) >> 5;
|
|
for (u = 1; u < m; u ++) {
|
|
uint32_t aw, bw, naw;
|
|
|
|
aw = a[u];
|
|
bw = b[u];
|
|
naw = aw - bw - cc;
|
|
|
|
/*
|
|
* Carry is 1 if naw > aw. Carry is 1 also if naw == aw
|
|
* AND the carry was already 1.
|
|
*/
|
|
cc = (cc & EQ(naw, aw)) | GT(naw, aw);
|
|
a[u] = MUX(ctl, naw, aw);
|
|
}
|
|
return cc;
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_div32.c */
|
|
|
|
/*
|
|
* Constant-time division. The dividend hi:lo is divided by the
|
|
* divisor d; the quotient is returned and the remainder is written
|
|
* in *r. If hi == d, then the quotient does not fit on 32 bits;
|
|
* returned value is thus truncated. If hi > d, returned values are
|
|
* indeterminate.
|
|
*/
|
|
static uint32_t br_divrem(uint32_t hi, uint32_t lo, uint32_t d, uint32_t *r)
|
|
{
|
|
/* TODO: optimize this */
|
|
uint32_t q;
|
|
uint32_t ch, cf;
|
|
int k;
|
|
|
|
q = 0;
|
|
ch = EQ(hi, d);
|
|
hi = MUX(ch, 0, hi);
|
|
for (k = 31; k > 0; k --) {
|
|
int j;
|
|
uint32_t w, ctl, hi2, lo2;
|
|
|
|
j = 32 - k;
|
|
w = (hi << j) | (lo >> k);
|
|
ctl = GE(w, d) | (hi >> k);
|
|
hi2 = (w - d) >> j;
|
|
lo2 = lo - (d << k);
|
|
hi = MUX(ctl, hi2, hi);
|
|
lo = MUX(ctl, lo2, lo);
|
|
q |= ctl << k;
|
|
}
|
|
cf = GE(lo, d) | hi;
|
|
q |= cf;
|
|
*r = MUX(cf, lo - d, lo);
|
|
return q;
|
|
}
|
|
|
|
/*
|
|
* Wrapper for br_divrem(); the remainder is returned, and the quotient
|
|
* is discarded.
|
|
*/
|
|
static uint32_t br_rem(uint32_t hi, uint32_t lo, uint32_t d)
|
|
{
|
|
uint32_t r;
|
|
|
|
br_divrem(hi, lo, d, &r);
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* Wrapper for br_divrem(); the quotient is returned, and the remainder
|
|
* is discarded.
|
|
*/
|
|
static uint32_t br_div(uint32_t hi, uint32_t lo, uint32_t d)
|
|
{
|
|
uint32_t r;
|
|
|
|
return br_divrem(hi, lo, d, &r);
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_muladd.c */
|
|
|
|
/*
|
|
* Multiply x[] by 2^32 and then add integer z, modulo m[]. This
|
|
* function assumes that x[] and m[] have the same announced bit
|
|
* length, and the announced bit length of m[] matches its true
|
|
* bit length.
|
|
*
|
|
* x[] and m[] MUST be distinct arrays.
|
|
*
|
|
* CT: only the common announced bit length of x and m leaks, not
|
|
* the values of x, z or m.
|
|
*/
|
|
static void br_i32_muladd_small(uint32_t *x, uint32_t z, const uint32_t *m)
|
|
{
|
|
uint32_t m_bitlen;
|
|
size_t u, mlen;
|
|
uint32_t a0, a1, b0, hi, g, q, tb;
|
|
uint32_t chf, clow, under, over;
|
|
uint64_t cc;
|
|
|
|
/*
|
|
* We can test on the modulus bit length since we accept to
|
|
* leak that length.
|
|
*/
|
|
m_bitlen = m[0];
|
|
if (m_bitlen == 0) {
|
|
return;
|
|
}
|
|
if (m_bitlen <= 32) {
|
|
x[1] = br_rem(x[1], z, m[1]);
|
|
return;
|
|
}
|
|
mlen = (m_bitlen + 31) >> 5;
|
|
|
|
/*
|
|
* Principle: we estimate the quotient (x*2^32+z)/m by
|
|
* doing a 64/32 division with the high words.
|
|
*
|
|
* Let:
|
|
* w = 2^32
|
|
* a = (w*a0 + a1) * w^N + a2
|
|
* b = b0 * w^N + b2
|
|
* such that:
|
|
* 0 <= a0 < w
|
|
* 0 <= a1 < w
|
|
* 0 <= a2 < w^N
|
|
* w/2 <= b0 < w
|
|
* 0 <= b2 < w^N
|
|
* a < w*b
|
|
* I.e. the two top words of a are a0:a1, the top word of b is
|
|
* b0, we ensured that b0 is "full" (high bit set), and a is
|
|
* such that the quotient q = a/b fits on one word (0 <= q < w).
|
|
*
|
|
* If a = b*q + r (with 0 <= r < q), we can estimate q by
|
|
* doing an Euclidean division on the top words:
|
|
* a0*w+a1 = b0*u + v (with 0 <= v < w)
|
|
* Then the following holds:
|
|
* 0 <= u <= w
|
|
* u-2 <= q <= u
|
|
*/
|
|
a0 = br_i32_word(x, m_bitlen - 32);
|
|
hi = x[mlen];
|
|
memmove(x + 2, x + 1, (mlen - 1) * sizeof *x);
|
|
x[1] = z;
|
|
a1 = br_i32_word(x, m_bitlen - 32);
|
|
b0 = br_i32_word(m, m_bitlen - 32);
|
|
|
|
/*
|
|
* We estimate a divisor q. If the quotient returned by br_div()
|
|
* is g:
|
|
* -- If a0 == b0 then g == 0; we want q = 0xFFFFFFFF.
|
|
* -- Otherwise:
|
|
* -- if g == 0 then we set q = 0;
|
|
* -- otherwise, we set q = g - 1.
|
|
* The properties described above then ensure that the true
|
|
* quotient is q-1, q or q+1.
|
|
*/
|
|
g = br_div(a0, a1, b0);
|
|
q = MUX(EQ(a0, b0), 0xFFFFFFFF, MUX(EQ(g, 0), 0, g - 1));
|
|
|
|
/*
|
|
* We subtract q*m from x (with the extra high word of value 'hi').
|
|
* Since q may be off by 1 (in either direction), we may have to
|
|
* add or subtract m afterwards.
|
|
*
|
|
* The 'tb' flag will be true (1) at the end of the loop if the
|
|
* result is greater than or equal to the modulus (not counting
|
|
* 'hi' or the carry).
|
|
*/
|
|
cc = 0;
|
|
tb = 1;
|
|
for (u = 1; u <= mlen; u ++) {
|
|
uint32_t mw, zw, xw, nxw;
|
|
uint64_t zl;
|
|
|
|
mw = m[u];
|
|
zl = MUL(mw, q) + cc;
|
|
cc = (uint32_t)(zl >> 32);
|
|
zw = (uint32_t)zl;
|
|
xw = x[u];
|
|
nxw = xw - zw;
|
|
cc += (uint64_t)GT(nxw, xw);
|
|
x[u] = nxw;
|
|
tb = MUX(EQ(nxw, mw), tb, GT(nxw, mw));
|
|
}
|
|
|
|
/*
|
|
* If we underestimated q, then either cc < hi (one extra bit
|
|
* beyond the top array word), or cc == hi and tb is true (no
|
|
* extra bit, but the result is not lower than the modulus). In
|
|
* these cases we must subtract m once.
|
|
*
|
|
* Otherwise, we may have overestimated, which will show as
|
|
* cc > hi (thus a negative result). Correction is adding m once.
|
|
*/
|
|
chf = (uint32_t)(cc >> 32);
|
|
clow = (uint32_t)cc;
|
|
over = chf | GT(clow, hi);
|
|
under = ~over & (tb | (~chf & LT(clow, hi)));
|
|
br_i32_add(x, m, over);
|
|
br_i32_sub(x, m, under);
|
|
}
|
|
|
|
/* from BearSSL's src/int/i32_reduce.c */
|
|
|
|
/*
|
|
* Reduce an integer (a[]) modulo another (m[]). The result is written
|
|
* in x[] and its announced bit length is set to be equal to that of m[].
|
|
*
|
|
* x[] MUST be distinct from a[] and m[].
|
|
*
|
|
* CT: only announced bit lengths leak, not values of x, a or m.
|
|
*/
|
|
static void br_i32_reduce(uint32_t *x, const uint32_t *a, const uint32_t *m)
|
|
{
|
|
uint32_t m_bitlen, a_bitlen;
|
|
size_t mlen, alen, u;
|
|
|
|
m_bitlen = m[0];
|
|
mlen = (m_bitlen + 31) >> 5;
|
|
|
|
x[0] = m_bitlen;
|
|
if (m_bitlen == 0) {
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the source is shorter, then simply copy all words from a[]
|
|
* and zero out the upper words.
|
|
*/
|
|
a_bitlen = a[0];
|
|
alen = (a_bitlen + 31) >> 5;
|
|
if (a_bitlen < m_bitlen) {
|
|
memcpy(x + 1, a + 1, alen * sizeof *a);
|
|
for (u = alen; u < mlen; u ++) {
|
|
x[u + 1] = 0;
|
|
}
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* The source length is at least equal to that of the modulus.
|
|
* We must thus copy N-1 words, and input the remaining words
|
|
* one by one.
|
|
*/
|
|
memcpy(x + 1, a + 2 + (alen - mlen), (mlen - 1) * sizeof *a);
|
|
x[mlen] = 0;
|
|
for (u = 1 + alen - mlen; u > 0; u --) {
|
|
br_i32_muladd_small(x, a[u], m);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* rsa_free_key_prop() - Free key properties
|
|
* @prop: Pointer to struct key_prop
|
|
*
|
|
* This function frees all the memories allocated by rsa_gen_key_prop().
|
|
*/
|
|
void rsa_free_key_prop(struct key_prop *prop)
|
|
{
|
|
if (!prop)
|
|
return;
|
|
|
|
free((void *)prop->modulus);
|
|
free((void *)prop->public_exponent);
|
|
free((void *)prop->rr);
|
|
|
|
free(prop);
|
|
}
|
|
|
|
/**
|
|
* rsa_gen_key_prop() - Generate key properties of RSA public key
|
|
* @key: Specifies key data in DER format
|
|
* @keylen: Length of @key
|
|
* @prop: Generated key property
|
|
*
|
|
* This function takes a blob of encoded RSA public key data in DER
|
|
* format, parse it and generate all the relevant properties
|
|
* in key_prop structure.
|
|
* Return a pointer to struct key_prop in @prop on success.
|
|
*
|
|
* Return: 0 on success, negative on error
|
|
*/
|
|
int rsa_gen_key_prop(const void *key, uint32_t keylen, struct key_prop **prop)
|
|
{
|
|
struct rsa_key rsa_key;
|
|
uint32_t *n = NULL, *rr = NULL, *rrtmp = NULL;
|
|
int rlen, i, ret = 0;
|
|
|
|
*prop = calloc(sizeof(**prop), 1);
|
|
if (!(*prop)) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
ret = rsa_parse_pub_key(&rsa_key, key, keylen);
|
|
if (ret)
|
|
goto out;
|
|
|
|
/* modulus */
|
|
/* removing leading 0's */
|
|
for (i = 0; i < rsa_key.n_sz && !rsa_key.n[i]; i++)
|
|
;
|
|
(*prop)->num_bits = (rsa_key.n_sz - i) * 8;
|
|
(*prop)->modulus = malloc(rsa_key.n_sz - i);
|
|
if (!(*prop)->modulus) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
memcpy((void *)(*prop)->modulus, &rsa_key.n[i], rsa_key.n_sz - i);
|
|
|
|
n = calloc(sizeof(uint32_t), 1 + ((*prop)->num_bits >> 5));
|
|
rr = calloc(sizeof(uint32_t), 1 + (((*prop)->num_bits * 2) >> 5));
|
|
rrtmp = calloc(sizeof(uint32_t), 2 + (((*prop)->num_bits * 2) >> 5));
|
|
if (!n || !rr || !rrtmp) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
/* exponent */
|
|
(*prop)->public_exponent = calloc(1, sizeof(uint64_t));
|
|
if (!(*prop)->public_exponent) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
memcpy((void *)(*prop)->public_exponent + sizeof(uint64_t)
|
|
- rsa_key.e_sz,
|
|
rsa_key.e, rsa_key.e_sz);
|
|
(*prop)->exp_len = sizeof(uint64_t);
|
|
|
|
/* n0 inverse */
|
|
br_i32_decode(n, &rsa_key.n[i], rsa_key.n_sz - i);
|
|
(*prop)->n0inv = br_i32_ninv32(n[1]);
|
|
|
|
/* R^2 mod n; R = 2^(num_bits) */
|
|
rlen = (*prop)->num_bits * 2; /* #bits of R^2 = (2^num_bits)^2 */
|
|
rr[0] = 0;
|
|
*(uint8_t *)&rr[0] = (1 << (rlen % 8));
|
|
for (i = 1; i < (((rlen + 31) >> 5) + 1); i++)
|
|
rr[i] = 0;
|
|
br_i32_decode(rrtmp, rr, ((rlen + 7) >> 3) + 1);
|
|
br_i32_reduce(rr, rrtmp, n);
|
|
|
|
rlen = ((*prop)->num_bits + 7) >> 3; /* #bytes of R^2 mod n */
|
|
(*prop)->rr = malloc(rlen);
|
|
if (!(*prop)->rr) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
br_i32_encode((void *)(*prop)->rr, rlen, rr);
|
|
|
|
out:
|
|
free(n);
|
|
free(rr);
|
|
free(rrtmp);
|
|
if (ret < 0)
|
|
rsa_free_key_prop(*prop);
|
|
return ret;
|
|
}
|