path: root/nss/lib/freebl/ecdecode.c

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef NSS_DISABLE_ECC

#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif

#include "blapi.h"
#include "secoid.h"
#include "secitem.h"
#include "secerr.h"
#include "ec.h"
#include "ecl-curve.h"

#define CHECK_OK(func) if (func == NULL) goto cleanup
#define CHECK_SEC_OK(func) if (SECSuccess != (rv = func)) goto cleanup

/*
 * Initializes a SECItem from a hexadecimal string
 *
 * Warning: This function ignores leading 00's, so any leading 00's
 * in the hexadecimal string must be optional.
 */
static SECItem *
hexString2SECItem(PLArenaPool *arena, SECItem *item, const char *str)
{
    int i = 0;
    int byteval = 0;
    int tmp = PORT_Strlen(str);

    if ((tmp % 2) != 0) return NULL;
    
    /* skip leading 00's unless the hex string is "00" */
    while ((tmp > 2) && (str[0] == '0') && (str[1] == '0')) {
        str += 2;
        tmp -= 2;
    }

    item->data = (unsigned char *) PORT_ArenaAlloc(arena, tmp/2);
    if (item->data == NULL) return NULL;
    item->len = tmp/2;

    while (str[i]) {
        if ((str[i] >= '0') && (str[i] <= '9'))
	    tmp = str[i] - '0';
	else if ((str[i] >= 'a') && (str[i] <= 'f'))
	    tmp = str[i] - 'a' + 10;
	else if ((str[i] >= 'A') && (str[i] <= 'F'))
	    tmp = str[i] - 'A' + 10;
	else
	    return NULL;

	byteval = byteval * 16 + tmp;
	if ((i % 2) != 0) {
	    item->data[i/2] = byteval;
	    byteval = 0;
	}
	i++;
    }

    return item;
}

/* Copy all of the fields from srcParams into dstParams
 */
SECStatus
EC_CopyParams(PLArenaPool *arena, ECParams *dstParams,
	      const ECParams *srcParams)
{
    SECStatus rv = SECFailure;

    dstParams->arena = arena;
    dstParams->type = srcParams->type;
    dstParams->fieldID.size = srcParams->fieldID.size;
    dstParams->fieldID.type = srcParams->fieldID.type;
    if (srcParams->fieldID.type == ec_field_GFp) {
	CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->fieldID.u.prime,
	    &srcParams->fieldID.u.prime));
    } else {
	CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->fieldID.u.poly,
	    &srcParams->fieldID.u.poly));
    }
    dstParams->fieldID.k1 = srcParams->fieldID.k1;
    dstParams->fieldID.k2 = srcParams->fieldID.k2;
    dstParams->fieldID.k3 = srcParams->fieldID.k3;
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->curve.a,
	&srcParams->curve.a));
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->curve.b,
	&srcParams->curve.b));
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->curve.seed,
	&srcParams->curve.seed));
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->base,
	&srcParams->base));
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->order,
	&srcParams->order));
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->DEREncoding,
	&srcParams->DEREncoding));
	dstParams->name = srcParams->name;
    CHECK_SEC_OK(SECITEM_CopyItem(arena, &dstParams->curveOID,
 	&srcParams->curveOID));
    dstParams->cofactor = srcParams->cofactor;

    return SECSuccess;

cleanup:
    return SECFailure;
}

static SECStatus
gf_populate_params(ECCurveName name, ECFieldType field_type, ECParams *params)
{
    SECStatus rv = SECFailure;
    const ECCurveParams *curveParams;
    /* 2 ['0'+'4'] + MAX_ECKEY_LEN * 2 [x,y] * 2 [hex string] + 1 ['\0'] */
    char genenc[3 + 2 * 2 * MAX_ECKEY_LEN];

    if ((name < ECCurve_noName) || (name > ECCurve_pastLastCurve)) goto cleanup;
    params->name = name;
    curveParams = ecCurve_map[params->name];
    CHECK_OK(curveParams);
    params->fieldID.size = curveParams->size;
    params->fieldID.type = field_type;
    if (field_type == ec_field_GFp) {
	CHECK_OK(hexString2SECItem(params->arena, &params->fieldID.u.prime, 
	    curveParams->irr));
    } else {
	CHECK_OK(hexString2SECItem(params->arena, &params->fieldID.u.poly, 
	    curveParams->irr));
    }
    CHECK_OK(hexString2SECItem(params->arena, &params->curve.a, 
	curveParams->curvea));
    CHECK_OK(hexString2SECItem(params->arena, &params->curve.b, 
	curveParams->curveb));
    genenc[0] = '0';
    genenc[1] = '4';
    genenc[2] = '\0';
    strcat(genenc, curveParams->genx);
    strcat(genenc, curveParams->geny);
    CHECK_OK(hexString2SECItem(params->arena, &params->base, genenc));
    CHECK_OK(hexString2SECItem(params->arena, &params->order, 
    	curveParams->order));
    params->cofactor = curveParams->cofactor;

    rv = SECSuccess;

cleanup:
    return rv;
}

SECStatus
EC_FillParams(PLArenaPool *arena, const SECItem *encodedParams,
    ECParams *params)
{
    SECStatus rv = SECFailure;
    SECOidTag tag;
    SECItem oid = { siBuffer, NULL, 0};

#if EC_DEBUG
    int i;

    printf("Encoded params in EC_DecodeParams: ");
    for (i = 0; i < encodedParams->len; i++) {
	    printf("%02x:", encodedParams->data[i]);
    }
    printf("\n");
#endif

    if ((encodedParams->len != ANSI_X962_CURVE_OID_TOTAL_LEN) &&
	(encodedParams->len != SECG_CURVE_OID_TOTAL_LEN)) {
	    PORT_SetError(SEC_ERROR_UNSUPPORTED_ELLIPTIC_CURVE);
	    return SECFailure;
    };

    oid.len = encodedParams->len - 2;
    oid.data = encodedParams->data + 2;
    if ((encodedParams->data[0] != SEC_ASN1_OBJECT_ID) ||
	((tag = SECOID_FindOIDTag(&oid)) == SEC_OID_UNKNOWN)) { 
	    PORT_SetError(SEC_ERROR_UNSUPPORTED_ELLIPTIC_CURVE);
	    return SECFailure;
    }

    params->arena = arena;
    params->cofactor = 0;
    params->type = ec_params_named;
    params->name = ECCurve_noName;

    /* For named curves, fill out curveOID */
    params->curveOID.len = oid.len;
    params->curveOID.data = (unsigned char *) PORT_ArenaAlloc(arena, oid.len);
    if (params->curveOID.data == NULL) goto cleanup;
    memcpy(params->curveOID.data, oid.data, oid.len);

#if EC_DEBUG
    printf("Curve: %s\n", SECOID_FindOIDTagDescription(tag));
#endif

    switch (tag) {

    /* Binary curves */

    case SEC_OID_ANSIX962_EC_C2PNB163V1:
	/* Populate params for c2pnb163v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB163V1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB163V2:
	/* Populate params for c2pnb163v2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB163V2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB163V3:
	/* Populate params for c2pnb163v3 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB163V3, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB176V1:
	/* Populate params for c2pnb176v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB176V1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB191V1:
	/* Populate params for c2tnb191v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB191V1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB191V2:
	/* Populate params for c2tnb191v2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB191V2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB191V3:
	/* Populate params for c2tnb191v3 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB191V3, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB208W1:
	/* Populate params for c2pnb208w1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB208W1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB239V1:
	/* Populate params for c2tnb239v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB239V1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB239V2:
	/* Populate params for c2tnb239v2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB239V2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB239V3:
	/* Populate params for c2tnb239v3 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB239V3, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB272W1:
	/* Populate params for c2pnb272w1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB272W1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB304W1:
	/* Populate params for c2pnb304w1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB304W1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB359V1:
	/* Populate params for c2tnb359v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB359V1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2PNB368W1:
	/* Populate params for c2pnb368w1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_PNB368W1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_C2TNB431R1:
	/* Populate params for c2tnb431r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_CHAR2_TNB431R1, ec_field_GF2m,
	    params) );
	break;
	
    case SEC_OID_SECG_EC_SECT113R1:
	/* Populate params for sect113r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_113R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT113R2:
	/* Populate params for sect113r2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_113R2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT131R1:
	/* Populate params for sect131r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_131R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT131R2:
	/* Populate params for sect131r2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_131R2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT163K1:
	/* Populate params for sect163k1
	 * (the NIST K-163 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_163K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT163R1:
	/* Populate params for sect163r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_163R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT163R2:
	/* Populate params for sect163r2
	 * (the NIST B-163 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_163R2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT193R1:
	/* Populate params for sect193r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_193R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT193R2:
	/* Populate params for sect193r2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_193R2, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT233K1:
	/* Populate params for sect233k1
	 * (the NIST K-233 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_233K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT233R1:
	/* Populate params for sect233r1
	 * (the NIST B-233 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_233R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT239K1:
	/* Populate params for sect239k1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_239K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT283K1:
        /* Populate params for sect283k1
	 * (the NIST K-283 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_283K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT283R1:
	/* Populate params for sect283r1
	 * (the NIST B-283 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_283R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT409K1:
	/* Populate params for sect409k1
	 * (the NIST K-409 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_409K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT409R1:
	/* Populate params for sect409r1
	 * (the NIST B-409 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_409R1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT571K1:
	/* Populate params for sect571k1
	 * (the NIST K-571 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_571K1, ec_field_GF2m,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECT571R1:
	/* Populate params for sect571r1
	 * (the NIST B-571 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_CHAR2_571R1, ec_field_GF2m,
	    params) );
	break;

    /* Prime curves */

    case SEC_OID_ANSIX962_EC_PRIME192V1:
	/* Populate params for prime192v1 aka secp192r1 
	 * (the NIST P-192 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_192V1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_PRIME192V2:
	/* Populate params for prime192v2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_192V2, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_PRIME192V3:
	/* Populate params for prime192v3 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_192V3, ec_field_GFp,
	    params) );
	break;
	
    case SEC_OID_ANSIX962_EC_PRIME239V1:
	/* Populate params for prime239v1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_239V1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_PRIME239V2:
	/* Populate params for prime239v2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_239V2, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_PRIME239V3:
	/* Populate params for prime239v3 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_239V3, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_ANSIX962_EC_PRIME256V1:
	/* Populate params for prime256v1 aka secp256r1
	 * (the NIST P-256 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_X9_62_PRIME_256V1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP112R1:
        /* Populate params for secp112r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_112R1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP112R2:
        /* Populate params for secp112r2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_112R2, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP128R1:
        /* Populate params for secp128r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_128R1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP128R2:
        /* Populate params for secp128r2 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_128R2, ec_field_GFp,
	    params) );
	break;
	
    case SEC_OID_SECG_EC_SECP160K1:
        /* Populate params for secp160k1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_160K1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP160R1:
        /* Populate params for secp160r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_160R1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP160R2:
	/* Populate params for secp160r1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_160R2, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP192K1:
	/* Populate params for secp192k1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_192K1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP224K1:
	/* Populate params for secp224k1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_224K1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP224R1:
	/* Populate params for secp224r1 
	 * (the NIST P-224 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_224R1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP256K1:
	/* Populate params for secp256k1 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_256K1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP384R1:
	/* Populate params for secp384r1
	 * (the NIST P-384 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_384R1, ec_field_GFp,
	    params) );
	break;

    case SEC_OID_SECG_EC_SECP521R1:
	/* Populate params for secp521r1 
	 * (the NIST P-521 curve)
	 */
	CHECK_SEC_OK( gf_populate_params(ECCurve_SECG_PRIME_521R1, ec_field_GFp,
	    params) );
	break;

    default:
	break;
    };

cleanup:
    if (!params->cofactor) {
	PORT_SetError(SEC_ERROR_UNSUPPORTED_ELLIPTIC_CURVE);
#if EC_DEBUG
	printf("Unrecognized curve, returning NULL params\n");
#endif
    }

    return rv;
}

SECStatus
EC_DecodeParams(const SECItem *encodedParams, ECParams **ecparams)
{
    PLArenaPool *arena;
    ECParams *params;
    SECStatus rv = SECFailure;

    /* Initialize an arena for the ECParams structure */
    if (!(arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE)))
	return SECFailure;

    params = (ECParams *)PORT_ArenaZAlloc(arena, sizeof(ECParams));
    if (!params) {
	PORT_FreeArena(arena, PR_TRUE);
	return SECFailure;
    }

    /* Copy the encoded params */
    SECITEM_AllocItem(arena, &(params->DEREncoding),
	encodedParams->len);
    memcpy(params->DEREncoding.data, encodedParams->data, encodedParams->len);

    /* Fill out the rest of the ECParams structure based on 
     * the encoded params 
     */
    rv = EC_FillParams(arena, encodedParams, params);
    if (rv == SECFailure) {
	PORT_FreeArena(arena, PR_TRUE);	
	return SECFailure;
    } else {
	*ecparams = params;;
	return SECSuccess;
    }
}

#endif /* NSS_DISABLE_ECC */