X-Git-Url: https://git.openssl.org/gitweb/?a=blobdiff_plain;f=crypto%2Fec%2Fecp_oct.c;h=14f62522cb5d0e9a162e40af1d1e3ee0a2cd196c;hb=9ff9bccc41c385ec2aa8ee2123f083b52b56b7b4;hp=374a0ee731ae0ccd7a7e7d22bd5535f889809445;hpb=84b08eee4b37c6594e43568f637d3aacbfd6105a;p=openssl.git diff --git a/crypto/ec/ecp_oct.c b/crypto/ec/ecp_oct.c index 374a0ee731..14f62522cb 100644 --- a/crypto/ec/ecp_oct.c +++ b/crypto/ec/ecp_oct.c @@ -1,8 +1,8 @@ -/* crypto/ec/ecp_oct.c */ -/* Includes code written by Lenka Fibikova - * for the OpenSSL project. - * Includes code written by Bodo Moeller for the OpenSSL project. -*/ +/* + * Includes code written by Lenka Fibikova + * for the OpenSSL project. Includes code written by Bodo Moeller for the + * OpenSSL project. + */ /* ==================================================================== * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. * @@ -11,7 +11,7 @@ * are met: * * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. + * 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 @@ -67,367 +67,357 @@ #include "ec_lcl.h" -int ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point, - const BIGNUM *x_, int y_bit, BN_CTX *ctx) - { - BN_CTX *new_ctx = NULL; - BIGNUM *tmp1, *tmp2, *x, *y; - int ret = 0; - - /* clear error queue*/ - ERR_clear_error(); - - if (ctx == NULL) - { - ctx = new_ctx = BN_CTX_new(); - if (ctx == NULL) - return 0; - } - - y_bit = (y_bit != 0); - - BN_CTX_start(ctx); - tmp1 = BN_CTX_get(ctx); - tmp2 = BN_CTX_get(ctx); - x = BN_CTX_get(ctx); - y = BN_CTX_get(ctx); - if (y == NULL) goto err; - - /* Recover y. We have a Weierstrass equation - * y^2 = x^3 + a*x + b, - * so y is one of the square roots of x^3 + a*x + b. - */ - - /* tmp1 := x^3 */ - if (!BN_nnmod(x, x_, &group->field,ctx)) goto err; - if (group->meth->field_decode == 0) - { - /* field_{sqr,mul} work on standard representation */ - if (!group->meth->field_sqr(group, tmp2, x_, ctx)) goto err; - if (!group->meth->field_mul(group, tmp1, tmp2, x_, ctx)) goto err; - } - else - { - if (!BN_mod_sqr(tmp2, x_, &group->field, ctx)) goto err; - if (!BN_mod_mul(tmp1, tmp2, x_, &group->field, ctx)) goto err; - } - - /* tmp1 := tmp1 + a*x */ - if (group->a_is_minus3) - { - if (!BN_mod_lshift1_quick(tmp2, x, &group->field)) goto err; - if (!BN_mod_add_quick(tmp2, tmp2, x, &group->field)) goto err; - if (!BN_mod_sub_quick(tmp1, tmp1, tmp2, &group->field)) goto err; - } - else - { - if (group->meth->field_decode) - { - if (!group->meth->field_decode(group, tmp2, &group->a, ctx)) goto err; - if (!BN_mod_mul(tmp2, tmp2, x, &group->field, ctx)) goto err; - } - else - { - /* field_mul works on standard representation */ - if (!group->meth->field_mul(group, tmp2, &group->a, x, ctx)) goto err; - } - - if (!BN_mod_add_quick(tmp1, tmp1, tmp2, &group->field)) goto err; - } - - /* tmp1 := tmp1 + b */ - if (group->meth->field_decode) - { - if (!group->meth->field_decode(group, tmp2, &group->b, ctx)) goto err; - if (!BN_mod_add_quick(tmp1, tmp1, tmp2, &group->field)) goto err; - } - else - { - if (!BN_mod_add_quick(tmp1, tmp1, &group->b, &group->field)) goto err; - } - - if (!BN_mod_sqrt(y, tmp1, &group->field, ctx)) - { - unsigned long err = ERR_peek_last_error(); - - if (ERR_GET_LIB(err) == ERR_LIB_BN && ERR_GET_REASON(err) == BN_R_NOT_A_SQUARE) - { - ERR_clear_error(); - ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT); - } - else - ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_BN_LIB); - goto err; - } - - if (y_bit != BN_is_odd(y)) - { - if (BN_is_zero(y)) - { - int kron; - - kron = BN_kronecker(x, &group->field, ctx); - if (kron == -2) goto err; - - if (kron == 1) - ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSION_BIT); - else - /* BN_mod_sqrt() should have cought this error (not a square) */ - ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT); - goto err; - } - if (!BN_usub(y, &group->field, y)) goto err; - } - if (y_bit != BN_is_odd(y)) - { - ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_INTERNAL_ERROR); - goto err; - } - - if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) goto err; - - ret = 1; +int ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *group, + EC_POINT *point, + const BIGNUM *x_, int y_bit, + BN_CTX *ctx) +{ + BN_CTX *new_ctx = NULL; + BIGNUM *tmp1, *tmp2, *x, *y; + int ret = 0; + + /* clear error queue */ + ERR_clear_error(); + + if (ctx == NULL) { + ctx = new_ctx = BN_CTX_new(); + if (ctx == NULL) + return 0; + } + + y_bit = (y_bit != 0); + + BN_CTX_start(ctx); + tmp1 = BN_CTX_get(ctx); + tmp2 = BN_CTX_get(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + /*- + * Recover y. We have a Weierstrass equation + * y^2 = x^3 + a*x + b, + * so y is one of the square roots of x^3 + a*x + b. + */ + + /* tmp1 := x^3 */ + if (!BN_nnmod(x, x_, group->field, ctx)) + goto err; + if (group->meth->field_decode == 0) { + /* field_{sqr,mul} work on standard representation */ + if (!group->meth->field_sqr(group, tmp2, x_, ctx)) + goto err; + if (!group->meth->field_mul(group, tmp1, tmp2, x_, ctx)) + goto err; + } else { + if (!BN_mod_sqr(tmp2, x_, group->field, ctx)) + goto err; + if (!BN_mod_mul(tmp1, tmp2, x_, group->field, ctx)) + goto err; + } + + /* tmp1 := tmp1 + a*x */ + if (group->a_is_minus3) { + if (!BN_mod_lshift1_quick(tmp2, x, group->field)) + goto err; + if (!BN_mod_add_quick(tmp2, tmp2, x, group->field)) + goto err; + if (!BN_mod_sub_quick(tmp1, tmp1, tmp2, group->field)) + goto err; + } else { + if (group->meth->field_decode) { + if (!group->meth->field_decode(group, tmp2, group->a, ctx)) + goto err; + if (!BN_mod_mul(tmp2, tmp2, x, group->field, ctx)) + goto err; + } else { + /* field_mul works on standard representation */ + if (!group->meth->field_mul(group, tmp2, group->a, x, ctx)) + goto err; + } + + if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field)) + goto err; + } + + /* tmp1 := tmp1 + b */ + if (group->meth->field_decode) { + if (!group->meth->field_decode(group, tmp2, group->b, ctx)) + goto err; + if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field)) + goto err; + } else { + if (!BN_mod_add_quick(tmp1, tmp1, group->b, group->field)) + goto err; + } + + if (!BN_mod_sqrt(y, tmp1, group->field, ctx)) { + unsigned long err = ERR_peek_last_error(); + + if (ERR_GET_LIB(err) == ERR_LIB_BN + && ERR_GET_REASON(err) == BN_R_NOT_A_SQUARE) { + ERR_clear_error(); + ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, + EC_R_INVALID_COMPRESSED_POINT); + } else + ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, + ERR_R_BN_LIB); + goto err; + } + + if (y_bit != BN_is_odd(y)) { + if (BN_is_zero(y)) { + int kron; + + kron = BN_kronecker(x, group->field, ctx); + if (kron == -2) + goto err; + + if (kron == 1) + ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, + EC_R_INVALID_COMPRESSION_BIT); + else + /* + * BN_mod_sqrt() should have cought this error (not a square) + */ + ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, + EC_R_INVALID_COMPRESSED_POINT); + goto err; + } + if (!BN_usub(y, group->field, y)) + goto err; + } + if (y_bit != BN_is_odd(y)) { + ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES, + ERR_R_INTERNAL_ERROR); + goto err; + } + + if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) + goto err; + + ret = 1; err: - BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); - return ret; - } - - -size_t ec_GFp_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, point_conversion_form_t form, - unsigned char *buf, size_t len, BN_CTX *ctx) - { - size_t ret; - BN_CTX *new_ctx = NULL; - int used_ctx = 0; - BIGNUM *x, *y; - size_t field_len, i, skip; - - if ((form != POINT_CONVERSION_COMPRESSED) - && (form != POINT_CONVERSION_UNCOMPRESSED) - && (form != POINT_CONVERSION_HYBRID)) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_INVALID_FORM); - goto err; - } - - if (EC_POINT_is_at_infinity(group, point)) - { - /* encodes to a single 0 octet */ - if (buf != NULL) - { - if (len < 1) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); - return 0; - } - buf[0] = 0; - } - return 1; - } - - - /* ret := required output buffer length */ - field_len = BN_num_bytes(&group->field); - ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; - - /* if 'buf' is NULL, just return required length */ - if (buf != NULL) - { - if (len < ret) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); - goto err; - } - - if (ctx == NULL) - { - ctx = new_ctx = BN_CTX_new(); - if (ctx == NULL) - return 0; - } - - BN_CTX_start(ctx); - used_ctx = 1; - x = BN_CTX_get(ctx); - y = BN_CTX_get(ctx); - if (y == NULL) goto err; - - if (!EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx)) goto err; - - if ((form == POINT_CONVERSION_COMPRESSED || form == POINT_CONVERSION_HYBRID) && BN_is_odd(y)) - buf[0] = form + 1; - else - buf[0] = form; - - i = 1; - - skip = field_len - BN_num_bytes(x); - if (skip > field_len) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); - goto err; - } - while (skip > 0) - { - buf[i++] = 0; - skip--; - } - skip = BN_bn2bin(x, buf + i); - i += skip; - if (i != 1 + field_len) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); - goto err; - } - - if (form == POINT_CONVERSION_UNCOMPRESSED || form == POINT_CONVERSION_HYBRID) - { - skip = field_len - BN_num_bytes(y); - if (skip > field_len) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); - goto err; - } - while (skip > 0) - { - buf[i++] = 0; - skip--; - } - skip = BN_bn2bin(y, buf + i); - i += skip; - } - - if (i != ret) - { - ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); - goto err; - } - } - - if (used_ctx) - BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); - return ret; + BN_CTX_end(ctx); + BN_CTX_free(new_ctx); + return ret; +} + +size_t ec_GFp_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, + point_conversion_form_t form, + unsigned char *buf, size_t len, BN_CTX *ctx) +{ + size_t ret; + BN_CTX *new_ctx = NULL; + int used_ctx = 0; + BIGNUM *x, *y; + size_t field_len, i, skip; + + if ((form != POINT_CONVERSION_COMPRESSED) + && (form != POINT_CONVERSION_UNCOMPRESSED) + && (form != POINT_CONVERSION_HYBRID)) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_INVALID_FORM); + goto err; + } + + if (EC_POINT_is_at_infinity(group, point)) { + /* encodes to a single 0 octet */ + if (buf != NULL) { + if (len < 1) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); + return 0; + } + buf[0] = 0; + } + return 1; + } + + /* ret := required output buffer length */ + field_len = BN_num_bytes(group->field); + ret = + (form == + POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len; + + /* if 'buf' is NULL, just return required length */ + if (buf != NULL) { + if (len < ret) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); + goto err; + } + + if (ctx == NULL) { + ctx = new_ctx = BN_CTX_new(); + if (ctx == NULL) + return 0; + } + + BN_CTX_start(ctx); + used_ctx = 1; + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + if (!EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx)) + goto err; + + if ((form == POINT_CONVERSION_COMPRESSED + || form == POINT_CONVERSION_HYBRID) && BN_is_odd(y)) + buf[0] = form + 1; + else + buf[0] = form; + + i = 1; + + skip = field_len - BN_num_bytes(x); + if (skip > field_len) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); + goto err; + } + while (skip > 0) { + buf[i++] = 0; + skip--; + } + skip = BN_bn2bin(x, buf + i); + i += skip; + if (i != 1 + field_len) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); + goto err; + } + + if (form == POINT_CONVERSION_UNCOMPRESSED + || form == POINT_CONVERSION_HYBRID) { + skip = field_len - BN_num_bytes(y); + if (skip > field_len) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); + goto err; + } + while (skip > 0) { + buf[i++] = 0; + skip--; + } + skip = BN_bn2bin(y, buf + i); + i += skip; + } + + if (i != ret) { + ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); + goto err; + } + } + + if (used_ctx) + BN_CTX_end(ctx); + BN_CTX_free(new_ctx); + return ret; err: - if (used_ctx) - BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); - return 0; - } - + if (used_ctx) + BN_CTX_end(ctx); + BN_CTX_free(new_ctx); + return 0; +} int ec_GFp_simple_oct2point(const EC_GROUP *group, EC_POINT *point, - const unsigned char *buf, size_t len, BN_CTX *ctx) - { - point_conversion_form_t form; - int y_bit; - BN_CTX *new_ctx = NULL; - BIGNUM *x, *y; - size_t field_len, enc_len; - int ret = 0; - - if (len == 0) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL); - return 0; - } - form = buf[0]; - y_bit = form & 1; - form = form & ~1U; - if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED) - && (form != POINT_CONVERSION_UNCOMPRESSED) - && (form != POINT_CONVERSION_HYBRID)) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - return 0; - } - if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - return 0; - } - - if (form == 0) - { - if (len != 1) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - return 0; - } - - return EC_POINT_set_to_infinity(group, point); - } - - field_len = BN_num_bytes(&group->field); - enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; - - if (len != enc_len) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - return 0; - } - - if (ctx == NULL) - { - ctx = new_ctx = BN_CTX_new(); - if (ctx == NULL) - return 0; - } - - BN_CTX_start(ctx); - x = BN_CTX_get(ctx); - y = BN_CTX_get(ctx); - if (y == NULL) goto err; - - if (!BN_bin2bn(buf + 1, field_len, x)) goto err; - if (BN_ucmp(x, &group->field) >= 0) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - goto err; - } - - if (form == POINT_CONVERSION_COMPRESSED) - { - if (!EC_POINT_set_compressed_coordinates_GFp(group, point, x, y_bit, ctx)) goto err; - } - else - { - if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) goto err; - if (BN_ucmp(y, &group->field) >= 0) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - goto err; - } - if (form == POINT_CONVERSION_HYBRID) - { - if (y_bit != BN_is_odd(y)) - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); - goto err; - } - } - - if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) goto err; - } - - if (!EC_POINT_is_on_curve(group, point, ctx)) /* test required by X9.62 */ - { - ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE); - goto err; - } - - ret = 1; - - err: - BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); - return ret; - } + const unsigned char *buf, size_t len, BN_CTX *ctx) +{ + point_conversion_form_t form; + int y_bit; + BN_CTX *new_ctx = NULL; + BIGNUM *x, *y; + size_t field_len, enc_len; + int ret = 0; + + if (len == 0) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL); + return 0; + } + form = buf[0]; + y_bit = form & 1; + form = form & ~1U; + if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED) + && (form != POINT_CONVERSION_UNCOMPRESSED) + && (form != POINT_CONVERSION_HYBRID)) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + return 0; + } + if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + return 0; + } + + if (form == 0) { + if (len != 1) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + return 0; + } + + return EC_POINT_set_to_infinity(group, point); + } + + field_len = BN_num_bytes(group->field); + enc_len = + (form == + POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len; + + if (len != enc_len) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + return 0; + } + + if (ctx == NULL) { + ctx = new_ctx = BN_CTX_new(); + if (ctx == NULL) + return 0; + } + + BN_CTX_start(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + if (!BN_bin2bn(buf + 1, field_len, x)) + goto err; + if (BN_ucmp(x, group->field) >= 0) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + goto err; + } + + if (form == POINT_CONVERSION_COMPRESSED) { + if (!EC_POINT_set_compressed_coordinates_GFp + (group, point, x, y_bit, ctx)) + goto err; + } else { + if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) + goto err; + if (BN_ucmp(y, group->field) >= 0) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + goto err; + } + if (form == POINT_CONVERSION_HYBRID) { + if (y_bit != BN_is_odd(y)) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); + goto err; + } + } + + if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) + goto err; + } + + /* test required by X9.62 */ + if (EC_POINT_is_on_curve(group, point, ctx) <= 0) { + ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE); + goto err; + } + + ret = 1; + err: + BN_CTX_end(ctx); + BN_CTX_free(new_ctx); + return ret; +}