diff options
Diffstat (limited to 'src/lib/libcrypto/ec/ec2_oct.c')
| -rw-r--r-- | src/lib/libcrypto/ec/ec2_oct.c | 311 |
1 files changed, 142 insertions, 169 deletions
diff --git a/src/lib/libcrypto/ec/ec2_oct.c b/src/lib/libcrypto/ec/ec2_oct.c index f1d75e5ddf..a856a5b1a7 100644 --- a/src/lib/libcrypto/ec/ec2_oct.c +++ b/src/lib/libcrypto/ec/ec2_oct.c | |||
| @@ -21,7 +21,7 @@ | |||
| 21 | * are met: | 21 | * are met: |
| 22 | * | 22 | * |
| 23 | * 1. Redistributions of source code must retain the above copyright | 23 | * 1. Redistributions of source code must retain the above copyright |
| 24 | * notice, this list of conditions and the following disclaimer. | 24 | * notice, this list of conditions and the following disclaimer. |
| 25 | * | 25 | * |
| 26 | * 2. Redistributions in binary form must reproduce the above copyright | 26 | * 2. Redistributions in binary form must reproduce the above copyright |
| 27 | * notice, this list of conditions and the following disclaimer in | 27 | * notice, this list of conditions and the following disclaimer in |
| @@ -74,11 +74,11 @@ | |||
| 74 | #ifndef OPENSSL_NO_EC2M | 74 | #ifndef OPENSSL_NO_EC2M |
| 75 | 75 | ||
| 76 | /* Calculates and sets the affine coordinates of an EC_POINT from the given | 76 | /* Calculates and sets the affine coordinates of an EC_POINT from the given |
| 77 | * compressed coordinates. Uses algorithm 2.3.4 of SEC 1. | 77 | * compressed coordinates. Uses algorithm 2.3.4 of SEC 1. |
| 78 | * Note that the simple implementation only uses affine coordinates. | 78 | * Note that the simple implementation only uses affine coordinates. |
| 79 | * | 79 | * |
| 80 | * The method is from the following publication: | 80 | * The method is from the following publication: |
| 81 | * | 81 | * |
| 82 | * Harper, Menezes, Vanstone: | 82 | * Harper, Menezes, Vanstone: |
| 83 | * "Public-Key Cryptosystems with Very Small Key Lengths", | 83 | * "Public-Key Cryptosystems with Very Small Key Lengths", |
| 84 | * EUROCRYPT '92, Springer-Verlag LNCS 658, | 84 | * EUROCRYPT '92, Springer-Verlag LNCS 658, |
| @@ -88,9 +88,10 @@ | |||
| 88 | * the same method, but claim no priority date earlier than July 29, 1994 | 88 | * the same method, but claim no priority date earlier than July 29, 1994 |
| 89 | * (and additionally fail to cite the EUROCRYPT '92 publication as prior art). | 89 | * (and additionally fail to cite the EUROCRYPT '92 publication as prior art). |
| 90 | */ | 90 | */ |
| 91 | int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point, | 91 | int |
| 92 | const BIGNUM *x_, int y_bit, BN_CTX *ctx) | 92 | ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point, |
| 93 | { | 93 | const BIGNUM *x_, int y_bit, BN_CTX *ctx) |
| 94 | { | ||
| 94 | BN_CTX *new_ctx = NULL; | 95 | BN_CTX *new_ctx = NULL; |
| 95 | BIGNUM *tmp, *x, *y, *z; | 96 | BIGNUM *tmp, *x, *y, *z; |
| 96 | int ret = 0, z0; | 97 | int ret = 0, z0; |
| @@ -98,13 +99,11 @@ int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *p | |||
| 98 | /* clear error queue */ | 99 | /* clear error queue */ |
| 99 | ERR_clear_error(); | 100 | ERR_clear_error(); |
| 100 | 101 | ||
| 101 | if (ctx == NULL) | 102 | if (ctx == NULL) { |
| 102 | { | ||
| 103 | ctx = new_ctx = BN_CTX_new(); | 103 | ctx = new_ctx = BN_CTX_new(); |
| 104 | if (ctx == NULL) | 104 | if (ctx == NULL) |
| 105 | return 0; | 105 | return 0; |
| 106 | } | 106 | } |
| 107 | |||
| 108 | y_bit = (y_bit != 0) ? 1 : 0; | 107 | y_bit = (y_bit != 0) ? 1 : 0; |
| 109 | 108 | ||
| 110 | BN_CTX_start(ctx); | 109 | BN_CTX_start(ctx); |
| @@ -112,59 +111,65 @@ int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *p | |||
| 112 | x = BN_CTX_get(ctx); | 111 | x = BN_CTX_get(ctx); |
| 113 | y = BN_CTX_get(ctx); | 112 | y = BN_CTX_get(ctx); |
| 114 | z = BN_CTX_get(ctx); | 113 | z = BN_CTX_get(ctx); |
| 115 | if (z == NULL) goto err; | 114 | if (z == NULL) |
| 115 | goto err; | ||
| 116 | 116 | ||
| 117 | if (!BN_GF2m_mod_arr(x, x_, group->poly)) goto err; | 117 | if (!BN_GF2m_mod_arr(x, x_, group->poly)) |
| 118 | if (BN_is_zero(x)) | 118 | goto err; |
| 119 | { | 119 | if (BN_is_zero(x)) { |
| 120 | if (!BN_GF2m_mod_sqrt_arr(y, &group->b, group->poly, ctx)) goto err; | 120 | if (!BN_GF2m_mod_sqrt_arr(y, &group->b, group->poly, ctx)) |
| 121 | } | 121 | goto err; |
| 122 | else | 122 | } else { |
| 123 | { | 123 | if (!group->meth->field_sqr(group, tmp, x, ctx)) |
| 124 | if (!group->meth->field_sqr(group, tmp, x, ctx)) goto err; | 124 | goto err; |
| 125 | if (!group->meth->field_div(group, tmp, &group->b, tmp, ctx)) goto err; | 125 | if (!group->meth->field_div(group, tmp, &group->b, tmp, ctx)) |
| 126 | if (!BN_GF2m_add(tmp, &group->a, tmp)) goto err; | 126 | goto err; |
| 127 | if (!BN_GF2m_add(tmp, x, tmp)) goto err; | 127 | if (!BN_GF2m_add(tmp, &group->a, tmp)) |
| 128 | if (!BN_GF2m_mod_solve_quad_arr(z, tmp, group->poly, ctx)) | 128 | goto err; |
| 129 | { | 129 | if (!BN_GF2m_add(tmp, x, tmp)) |
| 130 | goto err; | ||
| 131 | if (!BN_GF2m_mod_solve_quad_arr(z, tmp, group->poly, ctx)) { | ||
| 130 | unsigned long err = ERR_peek_last_error(); | 132 | unsigned long err = ERR_peek_last_error(); |
| 131 | 133 | ||
| 132 | if (ERR_GET_LIB(err) == ERR_LIB_BN && ERR_GET_REASON(err) == BN_R_NO_SOLUTION) | 134 | if (ERR_GET_LIB(err) == ERR_LIB_BN && |
| 133 | { | 135 | ERR_GET_REASON(err) == BN_R_NO_SOLUTION) { |
| 134 | ERR_clear_error(); | 136 | ERR_clear_error(); |
| 135 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT); | 137 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT); |
| 136 | } | 138 | } else |
| 137 | else | ||
| 138 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_BN_LIB); | 139 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_BN_LIB); |
| 139 | goto err; | 140 | goto err; |
| 140 | } | 141 | } |
| 141 | z0 = (BN_is_odd(z)) ? 1 : 0; | 142 | z0 = (BN_is_odd(z)) ? 1 : 0; |
| 142 | if (!group->meth->field_mul(group, y, x, z, ctx)) goto err; | 143 | if (!group->meth->field_mul(group, y, x, z, ctx)) |
| 143 | if (z0 != y_bit) | 144 | goto err; |
| 144 | { | 145 | if (z0 != y_bit) { |
| 145 | if (!BN_GF2m_add(y, y, x)) goto err; | 146 | if (!BN_GF2m_add(y, y, x)) |
| 146 | } | 147 | goto err; |
| 147 | } | 148 | } |
| 149 | } | ||
| 148 | 150 | ||
| 149 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; | 151 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) |
| 152 | goto err; | ||
| 150 | 153 | ||
| 151 | ret = 1; | 154 | ret = 1; |
| 152 | 155 | ||
| 153 | err: | 156 | err: |
| 154 | BN_CTX_end(ctx); | 157 | BN_CTX_end(ctx); |
| 155 | if (new_ctx != NULL) | 158 | if (new_ctx != NULL) |
| 156 | BN_CTX_free(new_ctx); | 159 | BN_CTX_free(new_ctx); |
| 157 | return ret; | 160 | return ret; |
| 158 | } | 161 | } |
| 159 | 162 | ||
| 160 | 163 | ||
| 161 | /* Converts an EC_POINT to an octet string. | 164 | /* Converts an EC_POINT to an octet string. |
| 162 | * If buf is NULL, the encoded length will be returned. | 165 | * If buf is NULL, the encoded length will be returned. |
| 163 | * If the length len of buf is smaller than required an error will be returned. | 166 | * If the length len of buf is smaller than required an error will be returned. |
| 164 | */ | 167 | */ |
| 165 | size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, point_conversion_form_t form, | 168 | size_t |
| 166 | unsigned char *buf, size_t len, BN_CTX *ctx) | 169 | ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, |
| 167 | { | 170 | point_conversion_form_t form, |
| 171 | unsigned char *buf, size_t len, BN_CTX * ctx) | ||
| 172 | { | ||
| 168 | size_t ret; | 173 | size_t ret; |
| 169 | BN_CTX *new_ctx = NULL; | 174 | BN_CTX *new_ctx = NULL; |
| 170 | int used_ctx = 0; | 175 | int used_ctx = 0; |
| @@ -172,131 +177,114 @@ size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, po | |||
| 172 | size_t field_len, i, skip; | 177 | size_t field_len, i, skip; |
| 173 | 178 | ||
| 174 | if ((form != POINT_CONVERSION_COMPRESSED) | 179 | if ((form != POINT_CONVERSION_COMPRESSED) |
| 175 | && (form != POINT_CONVERSION_UNCOMPRESSED) | 180 | && (form != POINT_CONVERSION_UNCOMPRESSED) |
| 176 | && (form != POINT_CONVERSION_HYBRID)) | 181 | && (form != POINT_CONVERSION_HYBRID)) { |
| 177 | { | ||
| 178 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_INVALID_FORM); | 182 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_INVALID_FORM); |
| 179 | goto err; | 183 | goto err; |
| 180 | } | 184 | } |
| 181 | 185 | if (EC_POINT_is_at_infinity(group, point)) { | |
| 182 | if (EC_POINT_is_at_infinity(group, point)) | ||
| 183 | { | ||
| 184 | /* encodes to a single 0 octet */ | 186 | /* encodes to a single 0 octet */ |
| 185 | if (buf != NULL) | 187 | if (buf != NULL) { |
| 186 | { | 188 | if (len < 1) { |
| 187 | if (len < 1) | ||
| 188 | { | ||
| 189 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); | 189 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); |
| 190 | return 0; | 190 | return 0; |
| 191 | } | ||
| 192 | buf[0] = 0; | ||
| 193 | } | 191 | } |
| 194 | return 1; | 192 | buf[0] = 0; |
| 195 | } | 193 | } |
| 196 | 194 | return 1; | |
| 197 | 195 | } | |
| 198 | /* ret := required output buffer length */ | 196 | /* ret := required output buffer length */ |
| 199 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; | 197 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; |
| 200 | ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; | 198 | ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : |
| 199 | 1 + 2 * field_len; | ||
| 201 | 200 | ||
| 202 | /* if 'buf' is NULL, just return required length */ | 201 | /* if 'buf' is NULL, just return required length */ |
| 203 | if (buf != NULL) | 202 | if (buf != NULL) { |
| 204 | { | 203 | if (len < ret) { |
| 205 | if (len < ret) | ||
| 206 | { | ||
| 207 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); | 204 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); |
| 208 | goto err; | 205 | goto err; |
| 209 | } | 206 | } |
| 210 | 207 | if (ctx == NULL) { | |
| 211 | if (ctx == NULL) | ||
| 212 | { | ||
| 213 | ctx = new_ctx = BN_CTX_new(); | 208 | ctx = new_ctx = BN_CTX_new(); |
| 214 | if (ctx == NULL) | 209 | if (ctx == NULL) |
| 215 | return 0; | 210 | return 0; |
| 216 | } | 211 | } |
| 217 | |||
| 218 | BN_CTX_start(ctx); | 212 | BN_CTX_start(ctx); |
| 219 | used_ctx = 1; | 213 | used_ctx = 1; |
| 220 | x = BN_CTX_get(ctx); | 214 | x = BN_CTX_get(ctx); |
| 221 | y = BN_CTX_get(ctx); | 215 | y = BN_CTX_get(ctx); |
| 222 | yxi = BN_CTX_get(ctx); | 216 | yxi = BN_CTX_get(ctx); |
| 223 | if (yxi == NULL) goto err; | 217 | if (yxi == NULL) |
| 218 | goto err; | ||
| 224 | 219 | ||
| 225 | if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; | 220 | if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx)) |
| 221 | goto err; | ||
| 226 | 222 | ||
| 227 | buf[0] = form; | 223 | buf[0] = form; |
| 228 | if ((form != POINT_CONVERSION_UNCOMPRESSED) && !BN_is_zero(x)) | 224 | if ((form != POINT_CONVERSION_UNCOMPRESSED) && !BN_is_zero(x)) { |
| 229 | { | 225 | if (!group->meth->field_div(group, yxi, y, x, ctx)) |
| 230 | if (!group->meth->field_div(group, yxi, y, x, ctx)) goto err; | 226 | goto err; |
| 231 | if (BN_is_odd(yxi)) buf[0]++; | 227 | if (BN_is_odd(yxi)) |
| 232 | } | 228 | buf[0]++; |
| 233 | 229 | } | |
| 234 | i = 1; | 230 | i = 1; |
| 235 | 231 | ||
| 236 | skip = field_len - BN_num_bytes(x); | 232 | skip = field_len - BN_num_bytes(x); |
| 237 | if (skip > field_len) | 233 | if (skip > field_len) { |
| 238 | { | ||
| 239 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); | 234 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 240 | goto err; | 235 | goto err; |
| 241 | } | 236 | } |
| 242 | while (skip > 0) | 237 | while (skip > 0) { |
| 243 | { | ||
| 244 | buf[i++] = 0; | 238 | buf[i++] = 0; |
| 245 | skip--; | 239 | skip--; |
| 246 | } | 240 | } |
| 247 | skip = BN_bn2bin(x, buf + i); | 241 | skip = BN_bn2bin(x, buf + i); |
| 248 | i += skip; | 242 | i += skip; |
| 249 | if (i != 1 + field_len) | 243 | if (i != 1 + field_len) { |
| 250 | { | ||
| 251 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); | 244 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 252 | goto err; | 245 | goto err; |
| 253 | } | 246 | } |
| 254 | 247 | if (form == POINT_CONVERSION_UNCOMPRESSED || | |
| 255 | if (form == POINT_CONVERSION_UNCOMPRESSED || form == POINT_CONVERSION_HYBRID) | 248 | form == POINT_CONVERSION_HYBRID) { |
| 256 | { | ||
| 257 | skip = field_len - BN_num_bytes(y); | 249 | skip = field_len - BN_num_bytes(y); |
| 258 | if (skip > field_len) | 250 | if (skip > field_len) { |
| 259 | { | ||
| 260 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); | 251 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 261 | goto err; | 252 | goto err; |
| 262 | } | 253 | } |
| 263 | while (skip > 0) | 254 | while (skip > 0) { |
| 264 | { | ||
| 265 | buf[i++] = 0; | 255 | buf[i++] = 0; |
| 266 | skip--; | 256 | skip--; |
| 267 | } | 257 | } |
| 268 | skip = BN_bn2bin(y, buf + i); | 258 | skip = BN_bn2bin(y, buf + i); |
| 269 | i += skip; | 259 | i += skip; |
| 270 | } | 260 | } |
| 271 | 261 | if (i != ret) { | |
| 272 | if (i != ret) | ||
| 273 | { | ||
| 274 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); | 262 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 275 | goto err; | 263 | goto err; |
| 276 | } | ||
| 277 | } | 264 | } |
| 278 | 265 | } | |
| 279 | if (used_ctx) | 266 | if (used_ctx) |
| 280 | BN_CTX_end(ctx); | 267 | BN_CTX_end(ctx); |
| 281 | if (new_ctx != NULL) | 268 | if (new_ctx != NULL) |
| 282 | BN_CTX_free(new_ctx); | 269 | BN_CTX_free(new_ctx); |
| 283 | return ret; | 270 | return ret; |
| 284 | 271 | ||
| 285 | err: | 272 | err: |
| 286 | if (used_ctx) | 273 | if (used_ctx) |
| 287 | BN_CTX_end(ctx); | 274 | BN_CTX_end(ctx); |
| 288 | if (new_ctx != NULL) | 275 | if (new_ctx != NULL) |
| 289 | BN_CTX_free(new_ctx); | 276 | BN_CTX_free(new_ctx); |
| 290 | return 0; | 277 | return 0; |
| 291 | } | 278 | } |
| 292 | 279 | ||
| 293 | 280 | ||
| 294 | /* Converts an octet string representation to an EC_POINT. | 281 | /* Converts an octet string representation to an EC_POINT. |
| 295 | * Note that the simple implementation only uses affine coordinates. | 282 | * Note that the simple implementation only uses affine coordinates. |
| 296 | */ | 283 | */ |
| 297 | int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, | 284 | int |
| 298 | const unsigned char *buf, size_t len, BN_CTX *ctx) | 285 | ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, |
| 299 | { | 286 | const unsigned char *buf, size_t len, BN_CTX *ctx) |
| 287 | { | ||
| 300 | point_conversion_form_t form; | 288 | point_conversion_form_t form; |
| 301 | int y_bit; | 289 | int y_bit; |
| 302 | BN_CTX *new_ctx = NULL; | 290 | BN_CTX *new_ctx = NULL; |
| @@ -304,104 +292,89 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, | |||
| 304 | size_t field_len, enc_len; | 292 | size_t field_len, enc_len; |
| 305 | int ret = 0; | 293 | int ret = 0; |
| 306 | 294 | ||
| 307 | if (len == 0) | 295 | if (len == 0) { |
| 308 | { | ||
| 309 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL); | 296 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL); |
| 310 | return 0; | 297 | return 0; |
| 311 | } | 298 | } |
| 312 | form = buf[0]; | 299 | form = buf[0]; |
| 313 | y_bit = form & 1; | 300 | y_bit = form & 1; |
| 314 | form = form & ~1U; | 301 | form = form & ~1U; |
| 315 | if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED) | 302 | if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED) && |
| 316 | && (form != POINT_CONVERSION_UNCOMPRESSED) | 303 | (form != POINT_CONVERSION_UNCOMPRESSED) && |
| 317 | && (form != POINT_CONVERSION_HYBRID)) | 304 | (form != POINT_CONVERSION_HYBRID)) { |
| 318 | { | ||
| 319 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 305 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 320 | return 0; | 306 | return 0; |
| 321 | } | 307 | } |
| 322 | if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) | 308 | if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) { |
| 323 | { | ||
| 324 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 309 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 325 | return 0; | 310 | return 0; |
| 326 | } | 311 | } |
| 327 | 312 | if (form == 0) { | |
| 328 | if (form == 0) | 313 | if (len != 1) { |
| 329 | { | ||
| 330 | if (len != 1) | ||
| 331 | { | ||
| 332 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 314 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 333 | return 0; | 315 | return 0; |
| 334 | } | ||
| 335 | |||
| 336 | return EC_POINT_set_to_infinity(group, point); | ||
| 337 | } | 316 | } |
| 338 | 317 | return EC_POINT_set_to_infinity(group, point); | |
| 318 | } | ||
| 339 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; | 319 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; |
| 340 | enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; | 320 | enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : |
| 321 | 1 + 2 * field_len; | ||
| 341 | 322 | ||
| 342 | if (len != enc_len) | 323 | if (len != enc_len) { |
| 343 | { | ||
| 344 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 324 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 345 | return 0; | 325 | return 0; |
| 346 | } | 326 | } |
| 347 | 327 | if (ctx == NULL) { | |
| 348 | if (ctx == NULL) | ||
| 349 | { | ||
| 350 | ctx = new_ctx = BN_CTX_new(); | 328 | ctx = new_ctx = BN_CTX_new(); |
| 351 | if (ctx == NULL) | 329 | if (ctx == NULL) |
| 352 | return 0; | 330 | return 0; |
| 353 | } | 331 | } |
| 354 | |||
| 355 | BN_CTX_start(ctx); | 332 | BN_CTX_start(ctx); |
| 356 | x = BN_CTX_get(ctx); | 333 | x = BN_CTX_get(ctx); |
| 357 | y = BN_CTX_get(ctx); | 334 | y = BN_CTX_get(ctx); |
| 358 | yxi = BN_CTX_get(ctx); | 335 | yxi = BN_CTX_get(ctx); |
| 359 | if (yxi == NULL) goto err; | 336 | if (yxi == NULL) |
| 337 | goto err; | ||
| 360 | 338 | ||
| 361 | if (!BN_bin2bn(buf + 1, field_len, x)) goto err; | 339 | if (!BN_bin2bn(buf + 1, field_len, x)) |
| 362 | if (BN_ucmp(x, &group->field) >= 0) | 340 | goto err; |
| 363 | { | 341 | if (BN_ucmp(x, &group->field) >= 0) { |
| 364 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 342 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 365 | goto err; | 343 | goto err; |
| 366 | } | 344 | } |
| 367 | 345 | if (form == POINT_CONVERSION_COMPRESSED) { | |
| 368 | if (form == POINT_CONVERSION_COMPRESSED) | 346 | if (!EC_POINT_set_compressed_coordinates_GF2m(group, point, x, y_bit, ctx)) |
| 369 | { | 347 | goto err; |
| 370 | if (!EC_POINT_set_compressed_coordinates_GF2m(group, point, x, y_bit, ctx)) goto err; | 348 | } else { |
| 371 | } | 349 | if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) |
| 372 | else | 350 | goto err; |
| 373 | { | 351 | if (BN_ucmp(y, &group->field) >= 0) { |
| 374 | if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) goto err; | ||
| 375 | if (BN_ucmp(y, &group->field) >= 0) | ||
| 376 | { | ||
| 377 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 352 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 378 | goto err; | 353 | goto err; |
| 379 | } | 354 | } |
| 380 | if (form == POINT_CONVERSION_HYBRID) | 355 | if (form == POINT_CONVERSION_HYBRID) { |
| 381 | { | 356 | if (!group->meth->field_div(group, yxi, y, x, ctx)) |
| 382 | if (!group->meth->field_div(group, yxi, y, x, ctx)) goto err; | 357 | goto err; |
| 383 | if (y_bit != BN_is_odd(yxi)) | 358 | if (y_bit != BN_is_odd(yxi)) { |
| 384 | { | ||
| 385 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); | 359 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 386 | goto err; | 360 | goto err; |
| 387 | } | ||
| 388 | } | 361 | } |
| 389 | |||
| 390 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; | ||
| 391 | } | 362 | } |
| 392 | 363 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) | |
| 393 | if (!EC_POINT_is_on_curve(group, point, ctx)) /* test required by X9.62 */ | 364 | goto err; |
| 394 | { | 365 | } |
| 366 | |||
| 367 | if (!EC_POINT_is_on_curve(group, point, ctx)) { | ||
| 368 | /* test required by X9.62 */ | ||
| 395 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE); | 369 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE); |
| 396 | goto err; | 370 | goto err; |
| 397 | } | 371 | } |
| 398 | |||
| 399 | ret = 1; | 372 | ret = 1; |
| 400 | 373 | ||
| 401 | err: | 374 | err: |
| 402 | BN_CTX_end(ctx); | 375 | BN_CTX_end(ctx); |
| 403 | if (new_ctx != NULL) | 376 | if (new_ctx != NULL) |
| 404 | BN_CTX_free(new_ctx); | 377 | BN_CTX_free(new_ctx); |
| 405 | return ret; | 378 | return ret; |
| 406 | } | 379 | } |
| 407 | #endif | 380 | #endif |
