void TEE_BigIntComputeExtendedGcd(TEE_BigInt *gcd, TEE_BigInt *u,
TEE_BigInt *v, const TEE_BigInt *op1,
const TEE_BigInt *op2)
{
mbedtls_mpi mpi_gcd_res;
mbedtls_mpi mpi_op1;
mbedtls_mpi mpi_op2;
mbedtls_mpi *pop2 = &mpi_op2;
get_mpi(&mpi_gcd_res, gcd);
get_mpi(&mpi_op1, op1);
if (op2 == op1)
pop2 = &mpi_op1;
else
get_mpi(&mpi_op2, op2);
if (!u && !v) {
if (gcd)
MPI_CHECK(mbedtls_mpi_gcd(&mpi_gcd_res, &mpi_op1,
pop2));
} else {
mbedtls_mpi mpi_u;
mbedtls_mpi mpi_v;
int8_t s1 = mpi_op1.s;
int8_t s2 = pop2->s;
int cmp;
mpi_op1.s = 1;
pop2->s = 1;
get_mpi(&mpi_u, u);
get_mpi(&mpi_v, v);
cmp = mbedtls_mpi_cmp_abs(&mpi_op1, pop2);
if (cmp == 0) {
MPI_CHECK(mbedtls_mpi_copy(&mpi_gcd_res, &mpi_op1));
MPI_CHECK(mbedtls_mpi_lset(&mpi_u, 1));
MPI_CHECK(mbedtls_mpi_lset(&mpi_v, 0));
} else if (cmp > 0) {
mpi_egcd(&mpi_gcd_res, &mpi_u, &mpi_v, &mpi_op1, pop2);
} else {
mpi_egcd(&mpi_gcd_res, &mpi_v, &mpi_u, pop2, &mpi_op1);
}
mpi_u.s *= s1;
mpi_v.s *= s2;
MPI_CHECK(copy_mpi_to_bigint(&mpi_u, u));
MPI_CHECK(copy_mpi_to_bigint(&mpi_v, v));
mbedtls_mpi_free(&mpi_u);
mbedtls_mpi_free(&mpi_v);
}
MPI_CHECK(copy_mpi_to_bigint(&mpi_gcd_res, gcd));
mbedtls_mpi_free(&mpi_gcd_res);
mbedtls_mpi_free(&mpi_op1);
if (pop2 == &mpi_op2)
mbedtls_mpi_free(&mpi_op2);
}
bool TEE_BigIntRelativePrime(const TEE_BigInt *op1, const TEE_BigInt *op2)
{
bool rc;
mbedtls_mpi mpi_op1;
mbedtls_mpi mpi_op2;
mbedtls_mpi *pop2 = &mpi_op2;
mbedtls_mpi gcd;
get_mpi(&mpi_op1, op1);
if (op2 == op1)
pop2 = &mpi_op1;
else
get_mpi(&mpi_op2, op2);
get_mpi(&gcd, NULL);
MPI_CHECK(mbedtls_mpi_gcd(&gcd, &mpi_op1, &mpi_op2));
rc = !mbedtls_mpi_cmp_int(&gcd, 1);
mbedtls_mpi_free(&gcd);
mbedtls_mpi_free(&mpi_op1);
if (pop2 == &mpi_op2)
mbedtls_mpi_free(&mpi_op2);
return rc;
}
/*
* Compute and write signature
*/
int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hlen,
unsigned char *sig, size_t *slen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
mbedtls_mpi r, s;
mbedtls_mpi_init( &r );
mbedtls_mpi_init( &s );
#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
(void) f_rng;
(void) p_rng;
MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign_det( &ctx->grp, &r, &s, &ctx->d,
hash, hlen, md_alg ) );
#else
(void) md_alg;
MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign( &ctx->grp, &r, &s, &ctx->d,
hash, hlen, f_rng, p_rng ) );
#endif
MBEDTLS_MPI_CHK( ecdsa_signature_to_asn1( &r, &s, sig, slen ) );
cleanup:
mbedtls_mpi_free( &r );
mbedtls_mpi_free( &s );
return( ret );
}
/* modi */
static int modi(void *a, unsigned long b, unsigned long *c)
{
mbedtls_mpi bn_b;
mbedtls_mpi bn_c;
int res = 0;
mbedtls_mpi_init_mempool(&bn_b);
mbedtls_mpi_init_mempool(&bn_c);
res = set_int(&bn_b, b);
if (res)
return res;
res = mbedtls_mpi_mod_mpi(&bn_c, &bn_b, a);
if (!res)
*c = get_int(&bn_c);
mbedtls_mpi_free(&bn_b);
mbedtls_mpi_free(&bn_c);
if (res)
return CRYPT_MEM;
return CRYPT_OK;
}
static void bigint_binary(TEE_BigInt *dest, const TEE_BigInt *op1,
const TEE_BigInt *op2,
int (*func)(mbedtls_mpi *X, const mbedtls_mpi *A,
const mbedtls_mpi *B))
{
mbedtls_mpi mpi_dest;
mbedtls_mpi mpi_op1;
mbedtls_mpi mpi_op2;
mbedtls_mpi *pop1 = &mpi_op1;
mbedtls_mpi *pop2 = &mpi_op2;
get_mpi(&mpi_dest, dest);
if (op1 == dest)
pop1 = &mpi_dest;
else
get_mpi(&mpi_op1, op1);
if (op2 == dest)
pop2 = &mpi_dest;
else if (op2 == op1)
pop2 = pop1;
else
get_mpi(&mpi_op2, op2);
MPI_CHECK(func(&mpi_dest, pop1, pop2));
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest, dest));
mbedtls_mpi_free(&mpi_dest);
if (pop1 == &mpi_op1)
mbedtls_mpi_free(&mpi_op1);
if (pop2 == &mpi_op2)
mbedtls_mpi_free(&mpi_op2);
}
void TEE_BigIntInvMod(TEE_BigInt *dest, const TEE_BigInt *op,
const TEE_BigInt *n)
{
if (TEE_BigIntCmpS32(n, 2) < 0 || TEE_BigIntCmpS32(op, 0) == 0)
API_PANIC("too small modulus or trying to invert zero");
mbedtls_mpi mpi_dest;
mbedtls_mpi mpi_op;
mbedtls_mpi mpi_n;
mbedtls_mpi *pop = &mpi_op;
get_mpi(&mpi_dest, dest);
get_mpi(&mpi_n, n);
if (op == dest)
pop = &mpi_dest;
else
get_mpi(&mpi_op, op);
MPI_CHECK(mbedtls_mpi_inv_mod(&mpi_dest, pop, &mpi_n));
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest, dest));
mbedtls_mpi_free(&mpi_dest);
mbedtls_mpi_free(&mpi_n);
if (pop == &mpi_op)
mbedtls_mpi_free(&mpi_op);
}
/*
* Free the components of a sign restart sub-context
*/
static void ecdsa_restart_sig_free( mbedtls_ecdsa_restart_sig_ctx *ctx )
{
if( ctx == NULL )
return;
mbedtls_mpi_free( &ctx->k );
mbedtls_mpi_free( &ctx->r );
}
/*
* Free the components of a DHM key
*/
void mbedtls_dhm_free( mbedtls_dhm_context *ctx )
{
mbedtls_mpi_free( &ctx->pX); mbedtls_mpi_free( &ctx->Vf ); mbedtls_mpi_free( &ctx->Vi );
mbedtls_mpi_free( &ctx->RP ); mbedtls_mpi_free( &ctx->K ); mbedtls_mpi_free( &ctx->GY );
mbedtls_mpi_free( &ctx->GX ); mbedtls_mpi_free( &ctx->X ); mbedtls_mpi_free( &ctx->G );
mbedtls_mpi_free( &ctx->P );
mbedtls_zeroize( ctx, sizeof( mbedtls_dhm_context ) );
}
/*
* Restartable read and check signature
*/
int mbedtls_ecdsa_read_signature_restartable( mbedtls_ecdsa_context *ctx,
const unsigned char *hash, size_t hlen,
const unsigned char *sig, size_t slen,
mbedtls_ecdsa_restart_ctx *rs_ctx )
{
int ret;
unsigned char *p = (unsigned char *) sig;
const unsigned char *end = sig + slen;
size_t len;
mbedtls_mpi r, s;
mbedtls_mpi_init( &r );
mbedtls_mpi_init( &s );
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
{
ret += MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
if( p + len != end )
{
ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
goto cleanup;
}
if( ( ret = mbedtls_asn1_get_mpi( &p, end, &r ) ) != 0 ||
( ret = mbedtls_asn1_get_mpi( &p, end, &s ) ) != 0 )
{
ret += MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
#if defined(MBEDTLS_ECDSA_VERIFY_ALT)
if( ( ret = mbedtls_ecdsa_verify( &ctx->grp, hash, hlen,
&ctx->Q, &r, &s ) ) != 0 )
goto cleanup;
#else
if( ( ret = ecdsa_verify_restartable( &ctx->grp, hash, hlen,
&ctx->Q, &r, &s, rs_ctx ) ) != 0 )
goto cleanup;
#endif /* MBEDTLS_ECDSA_VERIFY_ALT */
/* At this point we know that the buffer starts with a valid signature.
* Return 0 if the buffer just contains the signature, and a specific
* error code if the valid signature is followed by more data. */
if( p != end )
ret = MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH;
cleanup:
mbedtls_mpi_free( &r );
mbedtls_mpi_free( &s );
return( ret );
}
/*
* Free the components of a verify restart sub-context
*/
static void ecdsa_restart_ver_free( mbedtls_ecdsa_restart_ver_ctx *ctx )
{
if( ctx == NULL )
return;
mbedtls_mpi_free( &ctx->u1 );
mbedtls_mpi_free( &ctx->u2 );
ecdsa_restart_ver_init( ctx );
}
bool ECDSA_Verify(COSE * pSigner, int index, const cn_cbor * pKey, int cbitDigest, const byte * rgbToSign, size_t cbToSign, cose_errback * perr)
{
mbedtls_ecp_keypair keypair;
mbedtls_mpi r;
mbedtls_mpi s;
mbedtls_md_type_t mdType;
const mbedtls_md_info_t *pmdInfo;
byte rgbDigest[MBEDTLS_MD_MAX_SIZE];
cn_cbor * pSig;
bool result = false;
mbedtls_ecp_keypair_init(&keypair);
mbedtls_mpi_init(&r);
mbedtls_mpi_init(&s);
if(!ECKey_From(pKey, &keypair, perr)) goto errorReturn;
switch(cbitDigest)
{
case 256:
mdType = MBEDTLS_MD_SHA256;
break;
case 384:
mdType = MBEDTLS_MD_SHA384;
break;
case 512:
mdType = MBEDTLS_MD_SHA512;
break;
default:
FAIL_CONDITION(COSE_ERR_INVALID_PARAMETER);
}
pmdInfo = mbedtls_md_info_from_type(mdType);
CHECK_CONDITION(pmdInfo != NULL, COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_md(pmdInfo, rgbToSign, cbToSign, rgbDigest) == 0, COSE_ERR_INVALID_PARAMETER);
pSig = _COSE_arrayget_int(pSigner, index);
CHECK_CONDITION((pSig != NULL) && (pSig->type == CN_CBOR_BYTES), COSE_ERR_INVALID_PARAMETER);
CHECK_CONDITION(mbedtls_mpi_read_binary( &r, pSig->v.bytes, pSig->length / 2 ) == 0, COSE_ERR_OUT_OF_MEMORY);
CHECK_CONDITION(mbedtls_mpi_read_binary( &s, pSig->v.bytes + pSig->length / 2, pSig->length / 2 ) == 0, COSE_ERR_OUT_OF_MEMORY);
CHECK_CONDITION(mbedtls_ecdsa_verify(&keypair.grp, rgbDigest, mbedtls_md_get_size(pmdInfo), &keypair.Q, &r, &s) == 0, COSE_ERR_CRYPTO_FAIL);
result = true;
errorReturn:
mbedtls_mpi_free(&r);
mbedtls_mpi_free(&s);
mbedtls_ecp_keypair_free(&keypair);
return result;
}
/*
* Free context
*/
void mbedtls_ecdh_free( mbedtls_ecdh_context *ctx )
{
if( ctx == NULL )
return;
mbedtls_ecp_group_free( &ctx->grp );
mbedtls_ecp_point_free( &ctx->Q );
mbedtls_ecp_point_free( &ctx->Qp );
mbedtls_ecp_point_free( &ctx->Vi );
mbedtls_ecp_point_free( &ctx->Vf );
mbedtls_mpi_free( &ctx->d );
mbedtls_mpi_free( &ctx->z );
mbedtls_mpi_free( &ctx->_d );
}
/*
* Deterministic signature wrapper
*/
int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
mbedtls_md_type_t md_alg )
{
int ret;
mbedtls_hmac_drbg_context rng_ctx;
unsigned char data[2 * MBEDTLS_ECP_MAX_BYTES];
size_t grp_len = ( grp->nbits + 7 ) / 8;
const mbedtls_md_info_t *md_info;
mbedtls_mpi h;
if( ( md_info = mbedtls_md_info_from_type( md_alg ) ) == NULL )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
mbedtls_mpi_init( &h );
mbedtls_hmac_drbg_init( &rng_ctx );
/* Use private key and message hash (reduced) to initialize HMAC_DRBG */
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( d, data, grp_len ) );
MBEDTLS_MPI_CHK( derive_mpi( grp, &h, buf, blen ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &h, data + grp_len, grp_len ) );
mbedtls_hmac_drbg_seed_buf( &rng_ctx, md_info, data, 2 * grp_len );
ret = mbedtls_ecdsa_sign( grp, r, s, d, buf, blen,
mbedtls_hmac_drbg_random, &rng_ctx );
cleanup:
mbedtls_hmac_drbg_free( &rng_ctx );
mbedtls_mpi_free( &h );
return( ret );
}
TEE_Result TEE_BigIntConvertToS32(int32_t *dest, const TEE_BigInt *src)
{
TEE_Result res = TEE_SUCCESS;
mbedtls_mpi mpi;
uint32_t v;
get_mpi(&mpi, src);
if (mbedtls_mpi_write_binary(&mpi, (void *)&v, sizeof(v))) {
res = TEE_ERROR_OVERFLOW;
goto out;
}
if (mpi.s > 0) {
if (ADD_OVERFLOW(0, TEE_U32_FROM_BIG_ENDIAN(v), dest))
res = TEE_ERROR_OVERFLOW;
} else {
if (SUB_OVERFLOW(0, TEE_U32_FROM_BIG_ENDIAN(v), dest))
res = TEE_ERROR_OVERFLOW;
}
out:
mbedtls_mpi_free(&mpi);
return res;
}
int32_t TEE_BigIntCmp(const TEE_BigInt *op1, const TEE_BigInt *op2)
{
mbedtls_mpi mpi1;
mbedtls_mpi mpi2;
int32_t rc;
get_mpi(&mpi1, op1);
get_mpi(&mpi2, op2);
rc = mbedtls_mpi_cmp_mpi(&mpi1, &mpi2);
mbedtls_mpi_free(&mpi1);
mbedtls_mpi_free(&mpi2);
return rc;
}
result_t X509Cert::get_serial(exlib::string &retVal)
{
mbedtls_x509_crt *crt = get_crt();
if (!crt)
return CHECK_ERROR(CALL_E_INVALID_CALL);
int32_t ret;
mbedtls_mpi serial;
mbedtls_mpi_init(&serial);
ret = mbedtls_mpi_read_binary(&serial, crt->serial.p, crt->serial.len);
if (ret != 0)
return CHECK_ERROR(_ssl::setError(ret));
retVal.resize(8192);
size_t sz = retVal.length();
ret = mbedtls_mpi_write_string(&serial, 10, &retVal[0], sz, &sz);
mbedtls_mpi_free(&serial);
if (ret != 0)
return CHECK_ERROR(_ssl::setError(ret));
retVal.resize(sz - 1);
return 0;
}
/* Z = (X * Y) mod M
Not an mbedTLS function
*/
int esp_mpi_mul_mpi_mod(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M)
{
int ret;
size_t num_words = hardware_words_needed(M);
mbedtls_mpi Rinv;
mbedtls_mpi_uint Mprime;
/* Calculate and load the first stage montgomery multiplication */
mbedtls_mpi_init(&Rinv);
MBEDTLS_MPI_CHK(calculate_rinv(&Rinv, M, num_words));
Mprime = modular_inverse(M);
esp_mpi_acquire_hardware();
/* Load M, X, Rinv, Mprime (Mprime is mod 2^32) */
mpi_to_mem_block(RSA_MEM_M_BLOCK_BASE, M, num_words);
mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, num_words);
mpi_to_mem_block(RSA_MEM_RB_BLOCK_BASE, &Rinv, num_words);
REG_WRITE(RSA_M_DASH_REG, (uint32_t)Mprime);
/* "mode" register loaded with number of 512-bit blocks, minus 1 */
REG_WRITE(RSA_MULT_MODE_REG, (num_words / 16) - 1);
/* Execute first stage montgomery multiplication */
execute_op(RSA_MULT_START_REG);
/* execute second stage */
MBEDTLS_MPI_CHK( modular_multiply_finish(Z, X, Y, num_words) );
esp_mpi_release_hardware();
cleanup:
mbedtls_mpi_free(&Rinv);
return ret;
}
/*
* Read and check signature
*/
int mbedtls_ecdsa_read_signature( mbedtls_ecdsa_context *ctx,
const unsigned char *hash, size_t hlen,
const unsigned char *sig, size_t slen )
{
int ret;
unsigned char *p = (unsigned char *) sig;
const unsigned char *end = sig + slen;
size_t len;
mbedtls_mpi r, s;
mbedtls_mpi_init( &r );
mbedtls_mpi_init( &s );
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
{
ret += MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
if( p + len != end )
{
ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
goto cleanup;
}
if( ( ret = mbedtls_asn1_get_mpi( &p, end, &r ) ) != 0 ||
( ret = mbedtls_asn1_get_mpi( &p, end, &s ) ) != 0 )
{
ret += MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
if( ( ret = mbedtls_ecdsa_verify( &ctx->grp, hash, hlen,
&ctx->Q, &r, &s ) ) != 0 )
goto cleanup;
if( p != end )
ret = MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH;
cleanup:
mbedtls_mpi_free( &r );
mbedtls_mpi_free( &s );
return( ret );
}
static void bigint_binary_mod(TEE_BigInt *dest, const TEE_BigInt *op1,
const TEE_BigInt *op2, const TEE_BigInt *n,
int (*func)(mbedtls_mpi *X, const mbedtls_mpi *A,
const mbedtls_mpi *B))
{
if (TEE_BigIntCmpS32(n, 2) < 0)
API_PANIC("Modulus is too short");
mbedtls_mpi mpi_dest;
mbedtls_mpi mpi_op1;
mbedtls_mpi mpi_op2;
mbedtls_mpi mpi_n;
mbedtls_mpi *pop1 = &mpi_op1;
mbedtls_mpi *pop2 = &mpi_op2;
mbedtls_mpi mpi_t;
get_mpi(&mpi_dest, dest);
get_mpi(&mpi_n, n);
if (op1 == dest)
pop1 = &mpi_dest;
else
get_mpi(&mpi_op1, op1);
if (op2 == dest)
pop2 = &mpi_dest;
else if (op2 == op1)
pop2 = pop1;
else
get_mpi(&mpi_op2, op2);
get_mpi(&mpi_t, NULL);
MPI_CHECK(func(&mpi_t, pop1, pop2));
MPI_CHECK(mbedtls_mpi_mod_mpi(&mpi_dest, &mpi_t, &mpi_n));
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest, dest));
mbedtls_mpi_free(&mpi_dest);
if (pop1 == &mpi_op1)
mbedtls_mpi_free(&mpi_op1);
if (pop2 == &mpi_op2)
mbedtls_mpi_free(&mpi_op2);
mbedtls_mpi_free(&mpi_t);
}
void mbedtls_x509write_crt_free( mbedtls_x509write_cert *ctx )
{
mbedtls_mpi_free( &ctx->serial );
mbedtls_asn1_free_named_data_list( &ctx->subject );
mbedtls_asn1_free_named_data_list( &ctx->issuer );
mbedtls_asn1_free_named_data_list( &ctx->extensions );
mbedtls_zeroize( ctx, sizeof(mbedtls_x509write_cert) );
}
void TEE_BigIntConvertFromS32(TEE_BigInt *dest, int32_t shortVal)
{
mbedtls_mpi mpi;
get_mpi(&mpi, dest);
MPI_CHECK(mbedtls_mpi_lset(&mpi, shortVal));
MPI_CHECK(copy_mpi_to_bigint(&mpi, dest));
mbedtls_mpi_free(&mpi);
}
/*
* Uninitialize a MPI.
*
* If the MPI is linked to a bigint the final changes (size and sign) will
* be copied back.
*
* If the MPI isn't linked to bigint it's only freed.
*/
static void put_mpi(mbedtls_mpi *mpi)
{
if (mpi->alloc_type == MBEDTLS_MPI_ALLOC_TYPE_STATIC) {
struct bigint_hdr *hdr = ((struct bigint_hdr *)mpi->p) - 1;
hdr->sign = mpi->s;
hdr->nblimbs = mpi->n;
} else {
mbedtls_mpi_free(mpi);
}
}
/*
* Verify sanity of parameter with regards to P
*
* Parameter should be: 2 <= public_param <= P - 2
*
* For more information on the attack, see:
* http://www.cl.cam.ac.uk/~rja14/Papers/psandqs.pdf
* http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2005-2643
*/
static int dhm_check_range( const mbedtls_mpi *param, const mbedtls_mpi *P )
{
mbedtls_mpi L, U;
int ret = MBEDTLS_ERR_DHM_BAD_INPUT_DATA;
mbedtls_mpi_init( &L ); mbedtls_mpi_init( &U );
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &L, 2 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &U, P, 2 ) );
if( mbedtls_mpi_cmp_mpi( param, &L ) >= 0 &&
mbedtls_mpi_cmp_mpi( param, &U ) <= 0 )
{
ret = 0;
}
cleanup:
mbedtls_mpi_free( &L ); mbedtls_mpi_free( &U );
return( ret );
}
void TEE_BigIntNeg(TEE_BigInt *dest, const TEE_BigInt *src)
{
mbedtls_mpi mpi_dest;
get_mpi(&mpi_dest, dest);
if (dest != src) {
mbedtls_mpi mpi_src;
get_mpi(&mpi_src, src);
MPI_CHECK(mbedtls_mpi_copy(&mpi_dest, &mpi_src));
mbedtls_mpi_free(&mpi_src);
}
mpi_dest.s *= -1;
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest, dest));
mbedtls_mpi_free(&mpi_dest);
}
void TEE_BigIntShiftRight(TEE_BigInt *dest, const TEE_BigInt *op, size_t bits)
{
mbedtls_mpi mpi_dest;
mbedtls_mpi mpi_op;
get_mpi(&mpi_dest, dest);
if (dest == op) {
MPI_CHECK(mbedtls_mpi_shift_r(&mpi_dest, bits));
goto out;
}
get_mpi(&mpi_op, op);
if (mbedtls_mpi_size(&mpi_dest) >= mbedtls_mpi_size(&mpi_op)) {
MPI_CHECK(mbedtls_mpi_copy(&mpi_dest, &mpi_op));
MPI_CHECK(mbedtls_mpi_shift_r(&mpi_dest, bits));
} else {
mbedtls_mpi mpi_t;
get_mpi(&mpi_t, NULL);
/*
* We're using a temporary buffer to avoid the corner case
* where destination is unexpectedly overflowed by up to
* @bits number of bits.
*/
MPI_CHECK(mbedtls_mpi_copy(&mpi_t, &mpi_op));
MPI_CHECK(mbedtls_mpi_shift_r(&mpi_t, bits));
MPI_CHECK(mbedtls_mpi_copy(&mpi_dest, &mpi_t));
mbedtls_mpi_free(&mpi_t);
}
mbedtls_mpi_free(&mpi_op);
out:
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest, dest));
mbedtls_mpi_free(&mpi_dest);
}
void TEE_BigIntDiv(TEE_BigInt *dest_q, TEE_BigInt *dest_r,
const TEE_BigInt *op1, const TEE_BigInt *op2)
{
mbedtls_mpi mpi_dest_q;
mbedtls_mpi mpi_dest_r;
mbedtls_mpi mpi_op1;
mbedtls_mpi mpi_op2;
mbedtls_mpi *pop1 = &mpi_op1;
mbedtls_mpi *pop2 = &mpi_op2;
get_mpi(&mpi_dest_q, dest_q);
get_mpi(&mpi_dest_r, dest_r);
if (op1 == dest_q)
pop1 = &mpi_dest_q;
else if (op1 == dest_r)
pop1 = &mpi_dest_r;
else
get_mpi(&mpi_op1, op1);
if (op2 == dest_q)
pop2 = &mpi_dest_q;
else if (op2 == dest_r)
pop2 = &mpi_dest_r;
else if (op2 == op1)
pop2 = pop1;
else
get_mpi(&mpi_op2, op2);
MPI_CHECK(mbedtls_mpi_div_mpi(&mpi_dest_q, &mpi_dest_r, pop1, pop2));
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest_q, dest_q));
MPI_CHECK(copy_mpi_to_bigint(&mpi_dest_r, dest_r));
mbedtls_mpi_free(&mpi_dest_q);
mbedtls_mpi_free(&mpi_dest_r);
if (pop1 == &mpi_op1)
mbedtls_mpi_free(&mpi_op1);
if (pop2 == &mpi_op2)
mbedtls_mpi_free(&mpi_op2);
}
uint32_t TEE_BigIntGetBitCount(const TEE_BigInt *src)
{
uint32_t rc;
mbedtls_mpi mpi;
get_mpi(&mpi, src);
rc = mbedtls_mpi_bitlen(&mpi);
mbedtls_mpi_free(&mpi);
return rc;
}
int32_t TEE_BigIntCmpS32(const TEE_BigInt *op, int32_t shortVal)
{
mbedtls_mpi mpi;
int32_t rc;
get_mpi(&mpi, op);
rc = mbedtls_mpi_cmp_int(&mpi, shortVal);
mbedtls_mpi_free(&mpi);
return rc;
}
/* Calculate Rinv = RR^2 mod M, where:
*
* R = b^n where b = 2^32, n=num_words,
* R = 2^N (where N=num_bits)
* RR = R^2 = 2^(2*N) (where N=num_bits=num_words*32)
*
* This calculation is computationally expensive (mbedtls_mpi_mod_mpi)
* so caller should cache the result where possible.
*
* DO NOT call this function while holding esp_mpi_acquire_hardware().
*
*/
static int calculate_rinv(mbedtls_mpi *Rinv, const mbedtls_mpi *M, int num_words)
{
int ret;
size_t num_bits = num_words * 32;
mbedtls_mpi RR;
mbedtls_mpi_init(&RR);
MBEDTLS_MPI_CHK(mbedtls_mpi_set_bit(&RR, num_bits * 2, 1));
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(Rinv, &RR, M));
cleanup:
mbedtls_mpi_free(&RR);
return ret;
}
bool TEE_BigIntGetBit(const TEE_BigInt *src, uint32_t bitIndex)
{
bool rc;
mbedtls_mpi mpi;
get_mpi(&mpi, src);
rc = mbedtls_mpi_get_bit(&mpi, bitIndex);
mbedtls_mpi_free(&mpi);
return rc;
}