Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 1 | /* |
| 2 | * DPP crypto functionality |
| 3 | * Copyright (c) 2017, Qualcomm Atheros, Inc. |
| 4 | * Copyright (c) 2018-2020, The Linux Foundation |
| 5 | * |
| 6 | * This software may be distributed under the terms of the BSD license. |
| 7 | * See README for more details. |
| 8 | */ |
| 9 | |
| 10 | #include "utils/includes.h" |
| 11 | #include <openssl/opensslv.h> |
| 12 | #include <openssl/err.h> |
| 13 | #include <openssl/asn1.h> |
| 14 | #include <openssl/asn1t.h> |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 15 | #include <openssl/pem.h> |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 16 | |
| 17 | #include "utils/common.h" |
| 18 | #include "utils/base64.h" |
| 19 | #include "utils/json.h" |
| 20 | #include "common/ieee802_11_defs.h" |
| 21 | #include "crypto/crypto.h" |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 22 | #include "crypto/random.h" |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 23 | #include "crypto/sha384.h" |
| 24 | #include "crypto/sha512.h" |
| 25 | #include "dpp.h" |
| 26 | #include "dpp_i.h" |
| 27 | |
| 28 | |
| 29 | #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ |
| 30 | (defined(LIBRESSL_VERSION_NUMBER) && \ |
| 31 | LIBRESSL_VERSION_NUMBER < 0x20700000L) |
| 32 | /* Compatibility wrappers for older versions. */ |
| 33 | |
| 34 | static int ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s) |
| 35 | { |
| 36 | sig->r = r; |
| 37 | sig->s = s; |
| 38 | return 1; |
| 39 | } |
| 40 | |
| 41 | |
| 42 | static void ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **pr, |
| 43 | const BIGNUM **ps) |
| 44 | { |
| 45 | if (pr) |
| 46 | *pr = sig->r; |
| 47 | if (ps) |
| 48 | *ps = sig->s; |
| 49 | } |
| 50 | |
| 51 | |
| 52 | static EC_KEY * EVP_PKEY_get0_EC_KEY(EVP_PKEY *pkey) |
| 53 | { |
| 54 | if (pkey->type != EVP_PKEY_EC) |
| 55 | return NULL; |
| 56 | return pkey->pkey.ec; |
| 57 | } |
| 58 | |
| 59 | #endif |
| 60 | |
| 61 | static const struct dpp_curve_params dpp_curves[] = { |
| 62 | /* The mandatory to support and the default NIST P-256 curve needs to |
| 63 | * be the first entry on this list. */ |
| 64 | { "prime256v1", 32, 32, 16, 32, "P-256", 19, "ES256" }, |
| 65 | { "secp384r1", 48, 48, 24, 48, "P-384", 20, "ES384" }, |
| 66 | { "secp521r1", 64, 64, 32, 66, "P-521", 21, "ES512" }, |
| 67 | { "brainpoolP256r1", 32, 32, 16, 32, "BP-256", 28, "BS256" }, |
| 68 | { "brainpoolP384r1", 48, 48, 24, 48, "BP-384", 29, "BS384" }, |
| 69 | { "brainpoolP512r1", 64, 64, 32, 64, "BP-512", 30, "BS512" }, |
| 70 | { NULL, 0, 0, 0, 0, NULL, 0, NULL } |
| 71 | }; |
| 72 | |
| 73 | |
| 74 | const struct dpp_curve_params * dpp_get_curve_name(const char *name) |
| 75 | { |
| 76 | int i; |
| 77 | |
| 78 | if (!name) |
| 79 | return &dpp_curves[0]; |
| 80 | |
| 81 | for (i = 0; dpp_curves[i].name; i++) { |
| 82 | if (os_strcmp(name, dpp_curves[i].name) == 0 || |
| 83 | (dpp_curves[i].jwk_crv && |
| 84 | os_strcmp(name, dpp_curves[i].jwk_crv) == 0)) |
| 85 | return &dpp_curves[i]; |
| 86 | } |
| 87 | return NULL; |
| 88 | } |
| 89 | |
| 90 | |
| 91 | const struct dpp_curve_params * dpp_get_curve_jwk_crv(const char *name) |
| 92 | { |
| 93 | int i; |
| 94 | |
| 95 | for (i = 0; dpp_curves[i].name; i++) { |
| 96 | if (dpp_curves[i].jwk_crv && |
| 97 | os_strcmp(name, dpp_curves[i].jwk_crv) == 0) |
| 98 | return &dpp_curves[i]; |
| 99 | } |
| 100 | return NULL; |
| 101 | } |
| 102 | |
| 103 | |
| 104 | static const struct dpp_curve_params * |
| 105 | dpp_get_curve_oid(const ASN1_OBJECT *poid) |
| 106 | { |
| 107 | ASN1_OBJECT *oid; |
| 108 | int i; |
| 109 | |
| 110 | for (i = 0; dpp_curves[i].name; i++) { |
| 111 | oid = OBJ_txt2obj(dpp_curves[i].name, 0); |
| 112 | if (oid && OBJ_cmp(poid, oid) == 0) |
| 113 | return &dpp_curves[i]; |
| 114 | } |
| 115 | return NULL; |
| 116 | } |
| 117 | |
| 118 | |
| 119 | const struct dpp_curve_params * dpp_get_curve_nid(int nid) |
| 120 | { |
| 121 | int i, tmp; |
| 122 | |
| 123 | if (!nid) |
| 124 | return NULL; |
| 125 | for (i = 0; dpp_curves[i].name; i++) { |
| 126 | tmp = OBJ_txt2nid(dpp_curves[i].name); |
| 127 | if (tmp == nid) |
| 128 | return &dpp_curves[i]; |
| 129 | } |
| 130 | return NULL; |
| 131 | } |
| 132 | |
| 133 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 134 | const struct dpp_curve_params * dpp_get_curve_ike_group(u16 group) |
| 135 | { |
| 136 | int i; |
| 137 | |
| 138 | for (i = 0; dpp_curves[i].name; i++) { |
| 139 | if (dpp_curves[i].ike_group == group) |
| 140 | return &dpp_curves[i]; |
| 141 | } |
| 142 | return NULL; |
| 143 | } |
| 144 | |
| 145 | |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 146 | void dpp_debug_print_point(const char *title, const EC_GROUP *group, |
| 147 | const EC_POINT *point) |
| 148 | { |
| 149 | BIGNUM *x, *y; |
| 150 | BN_CTX *ctx; |
| 151 | char *x_str = NULL, *y_str = NULL; |
| 152 | |
| 153 | if (!wpa_debug_show_keys) |
| 154 | return; |
| 155 | |
| 156 | ctx = BN_CTX_new(); |
| 157 | x = BN_new(); |
| 158 | y = BN_new(); |
| 159 | if (!ctx || !x || !y || |
| 160 | EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx) != 1) |
| 161 | goto fail; |
| 162 | |
| 163 | x_str = BN_bn2hex(x); |
| 164 | y_str = BN_bn2hex(y); |
| 165 | if (!x_str || !y_str) |
| 166 | goto fail; |
| 167 | |
| 168 | wpa_printf(MSG_DEBUG, "%s (%s,%s)", title, x_str, y_str); |
| 169 | |
| 170 | fail: |
| 171 | OPENSSL_free(x_str); |
| 172 | OPENSSL_free(y_str); |
| 173 | BN_free(x); |
| 174 | BN_free(y); |
| 175 | BN_CTX_free(ctx); |
| 176 | } |
| 177 | |
| 178 | |
| 179 | void dpp_debug_print_key(const char *title, EVP_PKEY *key) |
| 180 | { |
| 181 | EC_KEY *eckey; |
| 182 | BIO *out; |
| 183 | size_t rlen; |
| 184 | char *txt; |
| 185 | int res; |
| 186 | unsigned char *der = NULL; |
| 187 | int der_len; |
| 188 | const EC_GROUP *group; |
| 189 | const EC_POINT *point; |
| 190 | |
| 191 | out = BIO_new(BIO_s_mem()); |
| 192 | if (!out) |
| 193 | return; |
| 194 | |
| 195 | EVP_PKEY_print_private(out, key, 0, NULL); |
| 196 | rlen = BIO_ctrl_pending(out); |
| 197 | txt = os_malloc(rlen + 1); |
| 198 | if (txt) { |
| 199 | res = BIO_read(out, txt, rlen); |
| 200 | if (res > 0) { |
| 201 | txt[res] = '\0'; |
| 202 | wpa_printf(MSG_DEBUG, "%s: %s", title, txt); |
| 203 | } |
| 204 | os_free(txt); |
| 205 | } |
| 206 | BIO_free(out); |
| 207 | |
| 208 | eckey = EVP_PKEY_get1_EC_KEY(key); |
| 209 | if (!eckey) |
| 210 | return; |
| 211 | |
| 212 | group = EC_KEY_get0_group(eckey); |
| 213 | point = EC_KEY_get0_public_key(eckey); |
| 214 | if (group && point) |
| 215 | dpp_debug_print_point(title, group, point); |
| 216 | |
| 217 | der_len = i2d_ECPrivateKey(eckey, &der); |
| 218 | if (der_len > 0) |
| 219 | wpa_hexdump_key(MSG_DEBUG, "DPP: ECPrivateKey", der, der_len); |
| 220 | OPENSSL_free(der); |
| 221 | if (der_len <= 0) { |
| 222 | der = NULL; |
| 223 | der_len = i2d_EC_PUBKEY(eckey, &der); |
| 224 | if (der_len > 0) |
| 225 | wpa_hexdump(MSG_DEBUG, "DPP: EC_PUBKEY", der, der_len); |
| 226 | OPENSSL_free(der); |
| 227 | } |
| 228 | |
| 229 | EC_KEY_free(eckey); |
| 230 | } |
| 231 | |
| 232 | |
| 233 | static int dpp_hash_vector(const struct dpp_curve_params *curve, |
| 234 | size_t num_elem, const u8 *addr[], const size_t *len, |
| 235 | u8 *mac) |
| 236 | { |
| 237 | if (curve->hash_len == 32) |
| 238 | return sha256_vector(num_elem, addr, len, mac); |
| 239 | if (curve->hash_len == 48) |
| 240 | return sha384_vector(num_elem, addr, len, mac); |
| 241 | if (curve->hash_len == 64) |
| 242 | return sha512_vector(num_elem, addr, len, mac); |
| 243 | return -1; |
| 244 | } |
| 245 | |
| 246 | |
| 247 | int dpp_hkdf_expand(size_t hash_len, const u8 *secret, size_t secret_len, |
| 248 | const char *label, u8 *out, size_t outlen) |
| 249 | { |
| 250 | if (hash_len == 32) |
| 251 | return hmac_sha256_kdf(secret, secret_len, NULL, |
| 252 | (const u8 *) label, os_strlen(label), |
| 253 | out, outlen); |
| 254 | if (hash_len == 48) |
| 255 | return hmac_sha384_kdf(secret, secret_len, NULL, |
| 256 | (const u8 *) label, os_strlen(label), |
| 257 | out, outlen); |
| 258 | if (hash_len == 64) |
| 259 | return hmac_sha512_kdf(secret, secret_len, NULL, |
| 260 | (const u8 *) label, os_strlen(label), |
| 261 | out, outlen); |
| 262 | return -1; |
| 263 | } |
| 264 | |
| 265 | |
| 266 | int dpp_hmac_vector(size_t hash_len, const u8 *key, size_t key_len, |
| 267 | size_t num_elem, const u8 *addr[], const size_t *len, |
| 268 | u8 *mac) |
| 269 | { |
| 270 | if (hash_len == 32) |
| 271 | return hmac_sha256_vector(key, key_len, num_elem, addr, len, |
| 272 | mac); |
| 273 | if (hash_len == 48) |
| 274 | return hmac_sha384_vector(key, key_len, num_elem, addr, len, |
| 275 | mac); |
| 276 | if (hash_len == 64) |
| 277 | return hmac_sha512_vector(key, key_len, num_elem, addr, len, |
| 278 | mac); |
| 279 | return -1; |
| 280 | } |
| 281 | |
| 282 | |
| 283 | static int dpp_hmac(size_t hash_len, const u8 *key, size_t key_len, |
| 284 | const u8 *data, size_t data_len, u8 *mac) |
| 285 | { |
| 286 | if (hash_len == 32) |
| 287 | return hmac_sha256(key, key_len, data, data_len, mac); |
| 288 | if (hash_len == 48) |
| 289 | return hmac_sha384(key, key_len, data, data_len, mac); |
| 290 | if (hash_len == 64) |
| 291 | return hmac_sha512(key, key_len, data, data_len, mac); |
| 292 | return -1; |
| 293 | } |
| 294 | |
| 295 | |
| 296 | #ifdef CONFIG_DPP2 |
| 297 | |
| 298 | static int dpp_pbkdf2_f(size_t hash_len, |
| 299 | const u8 *password, size_t password_len, |
| 300 | const u8 *salt, size_t salt_len, |
| 301 | unsigned int iterations, unsigned int count, u8 *digest) |
| 302 | { |
| 303 | unsigned char tmp[DPP_MAX_HASH_LEN], tmp2[DPP_MAX_HASH_LEN]; |
| 304 | unsigned int i; |
| 305 | size_t j; |
| 306 | u8 count_buf[4]; |
| 307 | const u8 *addr[2]; |
| 308 | size_t len[2]; |
| 309 | |
| 310 | addr[0] = salt; |
| 311 | len[0] = salt_len; |
| 312 | addr[1] = count_buf; |
| 313 | len[1] = 4; |
| 314 | |
| 315 | /* F(P, S, c, i) = U1 xor U2 xor ... Uc |
| 316 | * U1 = PRF(P, S || i) |
| 317 | * U2 = PRF(P, U1) |
| 318 | * Uc = PRF(P, Uc-1) |
| 319 | */ |
| 320 | |
| 321 | WPA_PUT_BE32(count_buf, count); |
| 322 | if (dpp_hmac_vector(hash_len, password, password_len, 2, addr, len, |
| 323 | tmp)) |
| 324 | return -1; |
| 325 | os_memcpy(digest, tmp, hash_len); |
| 326 | |
| 327 | for (i = 1; i < iterations; i++) { |
| 328 | if (dpp_hmac(hash_len, password, password_len, tmp, hash_len, |
| 329 | tmp2)) |
| 330 | return -1; |
| 331 | os_memcpy(tmp, tmp2, hash_len); |
| 332 | for (j = 0; j < hash_len; j++) |
| 333 | digest[j] ^= tmp2[j]; |
| 334 | } |
| 335 | |
| 336 | return 0; |
| 337 | } |
| 338 | |
| 339 | |
| 340 | int dpp_pbkdf2(size_t hash_len, const u8 *password, size_t password_len, |
| 341 | const u8 *salt, size_t salt_len, unsigned int iterations, |
| 342 | u8 *buf, size_t buflen) |
| 343 | { |
| 344 | unsigned int count = 0; |
| 345 | unsigned char *pos = buf; |
| 346 | size_t left = buflen, plen; |
| 347 | unsigned char digest[DPP_MAX_HASH_LEN]; |
| 348 | |
| 349 | while (left > 0) { |
| 350 | count++; |
| 351 | if (dpp_pbkdf2_f(hash_len, password, password_len, |
| 352 | salt, salt_len, iterations, count, digest)) |
| 353 | return -1; |
| 354 | plen = left > hash_len ? hash_len : left; |
| 355 | os_memcpy(pos, digest, plen); |
| 356 | pos += plen; |
| 357 | left -= plen; |
| 358 | } |
| 359 | |
| 360 | return 0; |
| 361 | } |
| 362 | |
| 363 | #endif /* CONFIG_DPP2 */ |
| 364 | |
| 365 | |
| 366 | int dpp_bn2bin_pad(const BIGNUM *bn, u8 *pos, size_t len) |
| 367 | { |
| 368 | int num_bytes, offset; |
| 369 | |
| 370 | num_bytes = BN_num_bytes(bn); |
| 371 | if ((size_t) num_bytes > len) |
| 372 | return -1; |
| 373 | offset = len - num_bytes; |
| 374 | os_memset(pos, 0, offset); |
| 375 | BN_bn2bin(bn, pos + offset); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | |
| 380 | struct wpabuf * dpp_get_pubkey_point(EVP_PKEY *pkey, int prefix) |
| 381 | { |
| 382 | int len, res; |
| 383 | EC_KEY *eckey; |
| 384 | struct wpabuf *buf; |
| 385 | unsigned char *pos; |
| 386 | |
| 387 | eckey = EVP_PKEY_get1_EC_KEY(pkey); |
| 388 | if (!eckey) |
| 389 | return NULL; |
| 390 | EC_KEY_set_conv_form(eckey, POINT_CONVERSION_UNCOMPRESSED); |
| 391 | len = i2o_ECPublicKey(eckey, NULL); |
| 392 | if (len <= 0) { |
| 393 | wpa_printf(MSG_ERROR, |
| 394 | "DDP: Failed to determine public key encoding length"); |
| 395 | EC_KEY_free(eckey); |
| 396 | return NULL; |
| 397 | } |
| 398 | |
| 399 | buf = wpabuf_alloc(len); |
| 400 | if (!buf) { |
| 401 | EC_KEY_free(eckey); |
| 402 | return NULL; |
| 403 | } |
| 404 | |
| 405 | pos = wpabuf_put(buf, len); |
| 406 | res = i2o_ECPublicKey(eckey, &pos); |
| 407 | EC_KEY_free(eckey); |
| 408 | if (res != len) { |
| 409 | wpa_printf(MSG_ERROR, |
| 410 | "DDP: Failed to encode public key (res=%d/%d)", |
| 411 | res, len); |
| 412 | wpabuf_free(buf); |
| 413 | return NULL; |
| 414 | } |
| 415 | |
| 416 | if (!prefix) { |
| 417 | /* Remove 0x04 prefix to match DPP definition */ |
| 418 | pos = wpabuf_mhead(buf); |
| 419 | os_memmove(pos, pos + 1, len - 1); |
| 420 | buf->used--; |
| 421 | } |
| 422 | |
| 423 | return buf; |
| 424 | } |
| 425 | |
| 426 | |
| 427 | EVP_PKEY * dpp_set_pubkey_point_group(const EC_GROUP *group, |
| 428 | const u8 *buf_x, const u8 *buf_y, |
| 429 | size_t len) |
| 430 | { |
| 431 | EC_KEY *eckey = NULL; |
| 432 | BN_CTX *ctx; |
| 433 | EC_POINT *point = NULL; |
| 434 | BIGNUM *x = NULL, *y = NULL; |
| 435 | EVP_PKEY *pkey = NULL; |
| 436 | |
| 437 | ctx = BN_CTX_new(); |
| 438 | if (!ctx) { |
| 439 | wpa_printf(MSG_ERROR, "DPP: Out of memory"); |
| 440 | return NULL; |
| 441 | } |
| 442 | |
| 443 | point = EC_POINT_new(group); |
| 444 | x = BN_bin2bn(buf_x, len, NULL); |
| 445 | y = BN_bin2bn(buf_y, len, NULL); |
| 446 | if (!point || !x || !y) { |
| 447 | wpa_printf(MSG_ERROR, "DPP: Out of memory"); |
| 448 | goto fail; |
| 449 | } |
| 450 | |
| 451 | if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) { |
| 452 | wpa_printf(MSG_ERROR, |
| 453 | "DPP: OpenSSL: EC_POINT_set_affine_coordinates_GFp failed: %s", |
| 454 | ERR_error_string(ERR_get_error(), NULL)); |
| 455 | goto fail; |
| 456 | } |
| 457 | |
| 458 | if (!EC_POINT_is_on_curve(group, point, ctx) || |
| 459 | EC_POINT_is_at_infinity(group, point)) { |
| 460 | wpa_printf(MSG_ERROR, "DPP: Invalid point"); |
| 461 | goto fail; |
| 462 | } |
| 463 | dpp_debug_print_point("DPP: dpp_set_pubkey_point_group", group, point); |
| 464 | |
| 465 | eckey = EC_KEY_new(); |
| 466 | if (!eckey || |
| 467 | EC_KEY_set_group(eckey, group) != 1 || |
| 468 | EC_KEY_set_public_key(eckey, point) != 1) { |
| 469 | wpa_printf(MSG_ERROR, |
| 470 | "DPP: Failed to set EC_KEY: %s", |
| 471 | ERR_error_string(ERR_get_error(), NULL)); |
| 472 | goto fail; |
| 473 | } |
| 474 | EC_KEY_set_asn1_flag(eckey, OPENSSL_EC_NAMED_CURVE); |
| 475 | |
| 476 | pkey = EVP_PKEY_new(); |
| 477 | if (!pkey || EVP_PKEY_set1_EC_KEY(pkey, eckey) != 1) { |
| 478 | wpa_printf(MSG_ERROR, "DPP: Could not create EVP_PKEY"); |
| 479 | goto fail; |
| 480 | } |
| 481 | |
| 482 | out: |
| 483 | BN_free(x); |
| 484 | BN_free(y); |
| 485 | EC_KEY_free(eckey); |
| 486 | EC_POINT_free(point); |
| 487 | BN_CTX_free(ctx); |
| 488 | return pkey; |
| 489 | fail: |
| 490 | EVP_PKEY_free(pkey); |
| 491 | pkey = NULL; |
| 492 | goto out; |
| 493 | } |
| 494 | |
| 495 | |
| 496 | EVP_PKEY * dpp_set_pubkey_point(EVP_PKEY *group_key, const u8 *buf, size_t len) |
| 497 | { |
| 498 | const EC_KEY *eckey; |
| 499 | const EC_GROUP *group; |
| 500 | EVP_PKEY *pkey = NULL; |
| 501 | |
| 502 | if (len & 1) |
| 503 | return NULL; |
| 504 | |
| 505 | eckey = EVP_PKEY_get0_EC_KEY(group_key); |
| 506 | if (!eckey) { |
| 507 | wpa_printf(MSG_ERROR, |
| 508 | "DPP: Could not get EC_KEY from group_key"); |
| 509 | return NULL; |
| 510 | } |
| 511 | |
| 512 | group = EC_KEY_get0_group(eckey); |
| 513 | if (group) |
| 514 | pkey = dpp_set_pubkey_point_group(group, buf, buf + len / 2, |
| 515 | len / 2); |
| 516 | else |
| 517 | wpa_printf(MSG_ERROR, "DPP: Could not get EC group"); |
| 518 | |
| 519 | return pkey; |
| 520 | } |
| 521 | |
| 522 | |
| 523 | EVP_PKEY * dpp_gen_keypair(const struct dpp_curve_params *curve) |
| 524 | { |
| 525 | EVP_PKEY_CTX *kctx = NULL; |
| 526 | EC_KEY *ec_params = NULL; |
| 527 | EVP_PKEY *params = NULL, *key = NULL; |
| 528 | int nid; |
| 529 | |
| 530 | wpa_printf(MSG_DEBUG, "DPP: Generating a keypair"); |
| 531 | |
| 532 | nid = OBJ_txt2nid(curve->name); |
| 533 | if (nid == NID_undef) { |
| 534 | wpa_printf(MSG_INFO, "DPP: Unsupported curve %s", curve->name); |
| 535 | return NULL; |
| 536 | } |
| 537 | |
| 538 | ec_params = EC_KEY_new_by_curve_name(nid); |
| 539 | if (!ec_params) { |
| 540 | wpa_printf(MSG_ERROR, |
| 541 | "DPP: Failed to generate EC_KEY parameters"); |
| 542 | goto fail; |
| 543 | } |
| 544 | EC_KEY_set_asn1_flag(ec_params, OPENSSL_EC_NAMED_CURVE); |
| 545 | params = EVP_PKEY_new(); |
| 546 | if (!params || EVP_PKEY_set1_EC_KEY(params, ec_params) != 1) { |
| 547 | wpa_printf(MSG_ERROR, |
| 548 | "DPP: Failed to generate EVP_PKEY parameters"); |
| 549 | goto fail; |
| 550 | } |
| 551 | |
| 552 | kctx = EVP_PKEY_CTX_new(params, NULL); |
| 553 | if (!kctx || |
| 554 | EVP_PKEY_keygen_init(kctx) != 1 || |
| 555 | EVP_PKEY_keygen(kctx, &key) != 1) { |
| 556 | wpa_printf(MSG_ERROR, "DPP: Failed to generate EC key"); |
| 557 | key = NULL; |
| 558 | goto fail; |
| 559 | } |
| 560 | |
| 561 | if (wpa_debug_show_keys) |
| 562 | dpp_debug_print_key("Own generated key", key); |
| 563 | |
| 564 | fail: |
| 565 | EC_KEY_free(ec_params); |
| 566 | EVP_PKEY_free(params); |
| 567 | EVP_PKEY_CTX_free(kctx); |
| 568 | return key; |
| 569 | } |
| 570 | |
| 571 | |
| 572 | EVP_PKEY * dpp_set_keypair(const struct dpp_curve_params **curve, |
| 573 | const u8 *privkey, size_t privkey_len) |
| 574 | { |
| 575 | EVP_PKEY *pkey; |
| 576 | EC_KEY *eckey; |
| 577 | const EC_GROUP *group; |
| 578 | int nid; |
| 579 | |
| 580 | pkey = EVP_PKEY_new(); |
| 581 | if (!pkey) |
| 582 | return NULL; |
| 583 | eckey = d2i_ECPrivateKey(NULL, &privkey, privkey_len); |
| 584 | if (!eckey) { |
| 585 | wpa_printf(MSG_INFO, |
| 586 | "DPP: OpenSSL: d2i_ECPrivateKey() failed: %s", |
| 587 | ERR_error_string(ERR_get_error(), NULL)); |
| 588 | EVP_PKEY_free(pkey); |
| 589 | return NULL; |
| 590 | } |
| 591 | group = EC_KEY_get0_group(eckey); |
| 592 | if (!group) { |
| 593 | EC_KEY_free(eckey); |
| 594 | EVP_PKEY_free(pkey); |
| 595 | return NULL; |
| 596 | } |
| 597 | nid = EC_GROUP_get_curve_name(group); |
| 598 | *curve = dpp_get_curve_nid(nid); |
| 599 | if (!*curve) { |
| 600 | wpa_printf(MSG_INFO, |
| 601 | "DPP: Unsupported curve (nid=%d) in pre-assigned key", |
| 602 | nid); |
| 603 | EC_KEY_free(eckey); |
| 604 | EVP_PKEY_free(pkey); |
| 605 | return NULL; |
| 606 | } |
| 607 | |
| 608 | if (EVP_PKEY_assign_EC_KEY(pkey, eckey) != 1) { |
| 609 | EC_KEY_free(eckey); |
| 610 | EVP_PKEY_free(pkey); |
| 611 | return NULL; |
| 612 | } |
| 613 | return pkey; |
| 614 | } |
| 615 | |
| 616 | |
| 617 | typedef struct { |
| 618 | /* AlgorithmIdentifier ecPublicKey with optional parameters present |
| 619 | * as an OID identifying the curve */ |
| 620 | X509_ALGOR *alg; |
| 621 | /* Compressed format public key per ANSI X9.63 */ |
| 622 | ASN1_BIT_STRING *pub_key; |
| 623 | } DPP_BOOTSTRAPPING_KEY; |
| 624 | |
| 625 | ASN1_SEQUENCE(DPP_BOOTSTRAPPING_KEY) = { |
| 626 | ASN1_SIMPLE(DPP_BOOTSTRAPPING_KEY, alg, X509_ALGOR), |
| 627 | ASN1_SIMPLE(DPP_BOOTSTRAPPING_KEY, pub_key, ASN1_BIT_STRING) |
| 628 | } ASN1_SEQUENCE_END(DPP_BOOTSTRAPPING_KEY); |
| 629 | |
| 630 | IMPLEMENT_ASN1_FUNCTIONS(DPP_BOOTSTRAPPING_KEY); |
| 631 | |
| 632 | |
| 633 | static struct wpabuf * dpp_bootstrap_key_der(EVP_PKEY *key) |
| 634 | { |
| 635 | unsigned char *der = NULL; |
| 636 | int der_len; |
| 637 | const EC_KEY *eckey; |
| 638 | struct wpabuf *ret = NULL; |
| 639 | size_t len; |
| 640 | const EC_GROUP *group; |
| 641 | const EC_POINT *point; |
| 642 | BN_CTX *ctx; |
| 643 | DPP_BOOTSTRAPPING_KEY *bootstrap = NULL; |
| 644 | int nid; |
| 645 | |
| 646 | ctx = BN_CTX_new(); |
| 647 | eckey = EVP_PKEY_get0_EC_KEY(key); |
| 648 | if (!ctx || !eckey) |
| 649 | goto fail; |
| 650 | |
| 651 | group = EC_KEY_get0_group(eckey); |
| 652 | point = EC_KEY_get0_public_key(eckey); |
| 653 | if (!group || !point) |
| 654 | goto fail; |
| 655 | dpp_debug_print_point("DPP: bootstrap public key", group, point); |
| 656 | nid = EC_GROUP_get_curve_name(group); |
| 657 | |
| 658 | bootstrap = DPP_BOOTSTRAPPING_KEY_new(); |
| 659 | if (!bootstrap || |
| 660 | X509_ALGOR_set0(bootstrap->alg, OBJ_nid2obj(EVP_PKEY_EC), |
| 661 | V_ASN1_OBJECT, (void *) OBJ_nid2obj(nid)) != 1) |
| 662 | goto fail; |
| 663 | |
| 664 | len = EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, |
| 665 | NULL, 0, ctx); |
| 666 | if (len == 0) |
| 667 | goto fail; |
| 668 | |
| 669 | der = OPENSSL_malloc(len); |
| 670 | if (!der) |
| 671 | goto fail; |
| 672 | len = EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, |
| 673 | der, len, ctx); |
| 674 | |
| 675 | OPENSSL_free(bootstrap->pub_key->data); |
| 676 | bootstrap->pub_key->data = der; |
| 677 | der = NULL; |
| 678 | bootstrap->pub_key->length = len; |
| 679 | /* No unused bits */ |
| 680 | bootstrap->pub_key->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); |
| 681 | bootstrap->pub_key->flags |= ASN1_STRING_FLAG_BITS_LEFT; |
| 682 | |
| 683 | der_len = i2d_DPP_BOOTSTRAPPING_KEY(bootstrap, &der); |
| 684 | if (der_len <= 0) { |
| 685 | wpa_printf(MSG_ERROR, |
| 686 | "DDP: Failed to build DER encoded public key"); |
| 687 | goto fail; |
| 688 | } |
| 689 | |
| 690 | ret = wpabuf_alloc_copy(der, der_len); |
| 691 | fail: |
| 692 | DPP_BOOTSTRAPPING_KEY_free(bootstrap); |
| 693 | OPENSSL_free(der); |
| 694 | BN_CTX_free(ctx); |
| 695 | return ret; |
| 696 | } |
| 697 | |
| 698 | |
| 699 | int dpp_bootstrap_key_hash(struct dpp_bootstrap_info *bi) |
| 700 | { |
| 701 | struct wpabuf *der; |
| 702 | int res; |
| 703 | |
| 704 | der = dpp_bootstrap_key_der(bi->pubkey); |
| 705 | if (!der) |
| 706 | return -1; |
| 707 | wpa_hexdump_buf(MSG_DEBUG, "DPP: Compressed public key (DER)", |
| 708 | der); |
| 709 | res = dpp_bi_pubkey_hash(bi, wpabuf_head(der), wpabuf_len(der)); |
| 710 | if (res < 0) |
| 711 | wpa_printf(MSG_DEBUG, "DPP: Failed to hash public key"); |
| 712 | wpabuf_free(der); |
| 713 | return res; |
| 714 | } |
| 715 | |
| 716 | |
| 717 | int dpp_keygen(struct dpp_bootstrap_info *bi, const char *curve, |
| 718 | const u8 *privkey, size_t privkey_len) |
| 719 | { |
| 720 | char *base64 = NULL; |
| 721 | char *pos, *end; |
| 722 | size_t len; |
| 723 | struct wpabuf *der = NULL; |
| 724 | |
| 725 | bi->curve = dpp_get_curve_name(curve); |
| 726 | if (!bi->curve) { |
| 727 | wpa_printf(MSG_INFO, "DPP: Unsupported curve: %s", curve); |
| 728 | return -1; |
| 729 | } |
| 730 | |
| 731 | if (privkey) |
| 732 | bi->pubkey = dpp_set_keypair(&bi->curve, privkey, privkey_len); |
| 733 | else |
| 734 | bi->pubkey = dpp_gen_keypair(bi->curve); |
| 735 | if (!bi->pubkey) |
| 736 | goto fail; |
| 737 | bi->own = 1; |
| 738 | |
| 739 | der = dpp_bootstrap_key_der(bi->pubkey); |
| 740 | if (!der) |
| 741 | goto fail; |
| 742 | wpa_hexdump_buf(MSG_DEBUG, "DPP: Compressed public key (DER)", |
| 743 | der); |
| 744 | |
| 745 | if (dpp_bi_pubkey_hash(bi, wpabuf_head(der), wpabuf_len(der)) < 0) { |
| 746 | wpa_printf(MSG_DEBUG, "DPP: Failed to hash public key"); |
| 747 | goto fail; |
| 748 | } |
| 749 | |
| 750 | base64 = base64_encode(wpabuf_head(der), wpabuf_len(der), &len); |
| 751 | wpabuf_free(der); |
| 752 | der = NULL; |
| 753 | if (!base64) |
| 754 | goto fail; |
| 755 | pos = base64; |
| 756 | end = pos + len; |
| 757 | for (;;) { |
| 758 | pos = os_strchr(pos, '\n'); |
| 759 | if (!pos) |
| 760 | break; |
| 761 | os_memmove(pos, pos + 1, end - pos); |
| 762 | } |
| 763 | os_free(bi->pk); |
| 764 | bi->pk = base64; |
| 765 | return 0; |
| 766 | fail: |
| 767 | os_free(base64); |
| 768 | wpabuf_free(der); |
| 769 | return -1; |
| 770 | } |
| 771 | |
| 772 | |
| 773 | int dpp_derive_k1(const u8 *Mx, size_t Mx_len, u8 *k1, unsigned int hash_len) |
| 774 | { |
| 775 | u8 salt[DPP_MAX_HASH_LEN], prk[DPP_MAX_HASH_LEN]; |
| 776 | const char *info = "first intermediate key"; |
| 777 | int res; |
| 778 | |
| 779 | /* k1 = HKDF(<>, "first intermediate key", M.x) */ |
| 780 | |
| 781 | /* HKDF-Extract(<>, M.x) */ |
| 782 | os_memset(salt, 0, hash_len); |
| 783 | if (dpp_hmac(hash_len, salt, hash_len, Mx, Mx_len, prk) < 0) |
| 784 | return -1; |
| 785 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK = HKDF-Extract(<>, IKM=M.x)", |
| 786 | prk, hash_len); |
| 787 | |
| 788 | /* HKDF-Expand(PRK, info, L) */ |
| 789 | res = dpp_hkdf_expand(hash_len, prk, hash_len, info, k1, hash_len); |
| 790 | os_memset(prk, 0, hash_len); |
| 791 | if (res < 0) |
| 792 | return -1; |
| 793 | |
| 794 | wpa_hexdump_key(MSG_DEBUG, "DPP: k1 = HKDF-Expand(PRK, info, L)", |
| 795 | k1, hash_len); |
| 796 | return 0; |
| 797 | } |
| 798 | |
| 799 | |
| 800 | int dpp_derive_k2(const u8 *Nx, size_t Nx_len, u8 *k2, unsigned int hash_len) |
| 801 | { |
| 802 | u8 salt[DPP_MAX_HASH_LEN], prk[DPP_MAX_HASH_LEN]; |
| 803 | const char *info = "second intermediate key"; |
| 804 | int res; |
| 805 | |
| 806 | /* k2 = HKDF(<>, "second intermediate key", N.x) */ |
| 807 | |
| 808 | /* HKDF-Extract(<>, N.x) */ |
| 809 | os_memset(salt, 0, hash_len); |
| 810 | res = dpp_hmac(hash_len, salt, hash_len, Nx, Nx_len, prk); |
| 811 | if (res < 0) |
| 812 | return -1; |
| 813 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK = HKDF-Extract(<>, IKM=N.x)", |
| 814 | prk, hash_len); |
| 815 | |
| 816 | /* HKDF-Expand(PRK, info, L) */ |
| 817 | res = dpp_hkdf_expand(hash_len, prk, hash_len, info, k2, hash_len); |
| 818 | os_memset(prk, 0, hash_len); |
| 819 | if (res < 0) |
| 820 | return -1; |
| 821 | |
| 822 | wpa_hexdump_key(MSG_DEBUG, "DPP: k2 = HKDF-Expand(PRK, info, L)", |
| 823 | k2, hash_len); |
| 824 | return 0; |
| 825 | } |
| 826 | |
| 827 | |
| 828 | int dpp_derive_bk_ke(struct dpp_authentication *auth) |
| 829 | { |
| 830 | unsigned int hash_len = auth->curve->hash_len; |
| 831 | size_t nonce_len = auth->curve->nonce_len; |
| 832 | u8 nonces[2 * DPP_MAX_NONCE_LEN]; |
| 833 | const char *info_ke = "DPP Key"; |
| 834 | int res; |
| 835 | const u8 *addr[3]; |
| 836 | size_t len[3]; |
| 837 | size_t num_elem = 0; |
| 838 | |
| 839 | if (!auth->Mx_len || !auth->Nx_len) { |
| 840 | wpa_printf(MSG_DEBUG, |
| 841 | "DPP: Mx/Nx not available - cannot derive ke"); |
| 842 | return -1; |
| 843 | } |
| 844 | |
| 845 | /* bk = HKDF-Extract(I-nonce | R-nonce, M.x | N.x [| L.x]) */ |
| 846 | os_memcpy(nonces, auth->i_nonce, nonce_len); |
| 847 | os_memcpy(&nonces[nonce_len], auth->r_nonce, nonce_len); |
| 848 | addr[num_elem] = auth->Mx; |
| 849 | len[num_elem] = auth->Mx_len; |
| 850 | num_elem++; |
| 851 | addr[num_elem] = auth->Nx; |
| 852 | len[num_elem] = auth->Nx_len; |
| 853 | num_elem++; |
| 854 | if (auth->peer_bi && auth->own_bi) { |
| 855 | if (!auth->Lx_len) { |
| 856 | wpa_printf(MSG_DEBUG, |
| 857 | "DPP: Lx not available - cannot derive ke"); |
| 858 | return -1; |
| 859 | } |
| 860 | addr[num_elem] = auth->Lx; |
| 861 | len[num_elem] = auth->secret_len; |
| 862 | num_elem++; |
| 863 | } |
| 864 | res = dpp_hmac_vector(hash_len, nonces, 2 * nonce_len, |
| 865 | num_elem, addr, len, auth->bk); |
| 866 | if (res < 0) |
| 867 | return -1; |
| 868 | wpa_hexdump_key(MSG_DEBUG, |
| 869 | "DPP: bk = HKDF-Extract(I-nonce | R-nonce, M.x | N.x [| L.x])", |
| 870 | auth->bk, hash_len); |
| 871 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 872 | /* ke = HKDF-Expand(bk, "DPP Key", length) */ |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 873 | res = dpp_hkdf_expand(hash_len, auth->bk, hash_len, info_ke, auth->ke, |
| 874 | hash_len); |
| 875 | if (res < 0) |
| 876 | return -1; |
| 877 | |
| 878 | wpa_hexdump_key(MSG_DEBUG, |
| 879 | "DPP: ke = HKDF-Expand(bk, \"DPP Key\", length)", |
| 880 | auth->ke, hash_len); |
| 881 | |
| 882 | return 0; |
| 883 | } |
| 884 | |
| 885 | |
| 886 | int dpp_ecdh(EVP_PKEY *own, EVP_PKEY *peer, u8 *secret, size_t *secret_len) |
| 887 | { |
| 888 | EVP_PKEY_CTX *ctx; |
| 889 | int ret = -1; |
| 890 | |
| 891 | ERR_clear_error(); |
| 892 | *secret_len = 0; |
| 893 | |
| 894 | ctx = EVP_PKEY_CTX_new(own, NULL); |
| 895 | if (!ctx) { |
| 896 | wpa_printf(MSG_ERROR, "DPP: EVP_PKEY_CTX_new failed: %s", |
| 897 | ERR_error_string(ERR_get_error(), NULL)); |
| 898 | return -1; |
| 899 | } |
| 900 | |
| 901 | if (EVP_PKEY_derive_init(ctx) != 1) { |
| 902 | wpa_printf(MSG_ERROR, "DPP: EVP_PKEY_derive_init failed: %s", |
| 903 | ERR_error_string(ERR_get_error(), NULL)); |
| 904 | goto fail; |
| 905 | } |
| 906 | |
| 907 | if (EVP_PKEY_derive_set_peer(ctx, peer) != 1) { |
| 908 | wpa_printf(MSG_ERROR, |
| 909 | "DPP: EVP_PKEY_derive_set_peet failed: %s", |
| 910 | ERR_error_string(ERR_get_error(), NULL)); |
| 911 | goto fail; |
| 912 | } |
| 913 | |
| 914 | if (EVP_PKEY_derive(ctx, NULL, secret_len) != 1) { |
| 915 | wpa_printf(MSG_ERROR, "DPP: EVP_PKEY_derive(NULL) failed: %s", |
| 916 | ERR_error_string(ERR_get_error(), NULL)); |
| 917 | goto fail; |
| 918 | } |
| 919 | |
| 920 | if (*secret_len > DPP_MAX_SHARED_SECRET_LEN) { |
| 921 | u8 buf[200]; |
| 922 | int level = *secret_len > 200 ? MSG_ERROR : MSG_DEBUG; |
| 923 | |
| 924 | /* It looks like OpenSSL can return unexpectedly large buffer |
| 925 | * need for shared secret from EVP_PKEY_derive(NULL) in some |
| 926 | * cases. For example, group 19 has shown cases where secret_len |
| 927 | * is set to 72 even though the actual length ends up being |
| 928 | * updated to 32 when EVP_PKEY_derive() is called with a buffer |
| 929 | * for the value. Work around this by trying to fetch the value |
| 930 | * and continue if it is within supported range even when the |
| 931 | * initial buffer need is claimed to be larger. */ |
| 932 | wpa_printf(level, |
| 933 | "DPP: Unexpected secret_len=%d from EVP_PKEY_derive()", |
| 934 | (int) *secret_len); |
| 935 | if (*secret_len > 200) |
| 936 | goto fail; |
| 937 | if (EVP_PKEY_derive(ctx, buf, secret_len) != 1) { |
| 938 | wpa_printf(MSG_ERROR, "DPP: EVP_PKEY_derive failed: %s", |
| 939 | ERR_error_string(ERR_get_error(), NULL)); |
| 940 | goto fail; |
| 941 | } |
| 942 | if (*secret_len > DPP_MAX_SHARED_SECRET_LEN) { |
| 943 | wpa_printf(MSG_ERROR, |
| 944 | "DPP: Unexpected secret_len=%d from EVP_PKEY_derive()", |
| 945 | (int) *secret_len); |
| 946 | goto fail; |
| 947 | } |
| 948 | wpa_hexdump_key(MSG_DEBUG, "DPP: Unexpected secret_len change", |
| 949 | buf, *secret_len); |
| 950 | os_memcpy(secret, buf, *secret_len); |
| 951 | forced_memzero(buf, sizeof(buf)); |
| 952 | goto done; |
| 953 | } |
| 954 | |
| 955 | if (EVP_PKEY_derive(ctx, secret, secret_len) != 1) { |
| 956 | wpa_printf(MSG_ERROR, "DPP: EVP_PKEY_derive failed: %s", |
| 957 | ERR_error_string(ERR_get_error(), NULL)); |
| 958 | goto fail; |
| 959 | } |
| 960 | |
| 961 | done: |
| 962 | ret = 0; |
| 963 | |
| 964 | fail: |
| 965 | EVP_PKEY_CTX_free(ctx); |
| 966 | return ret; |
| 967 | } |
| 968 | |
| 969 | |
| 970 | int dpp_bi_pubkey_hash(struct dpp_bootstrap_info *bi, |
| 971 | const u8 *data, size_t data_len) |
| 972 | { |
| 973 | const u8 *addr[2]; |
| 974 | size_t len[2]; |
| 975 | |
| 976 | addr[0] = data; |
| 977 | len[0] = data_len; |
| 978 | if (sha256_vector(1, addr, len, bi->pubkey_hash) < 0) |
| 979 | return -1; |
| 980 | wpa_hexdump(MSG_DEBUG, "DPP: Public key hash", |
| 981 | bi->pubkey_hash, SHA256_MAC_LEN); |
| 982 | |
| 983 | addr[0] = (const u8 *) "chirp"; |
| 984 | len[0] = 5; |
| 985 | addr[1] = data; |
| 986 | len[1] = data_len; |
| 987 | if (sha256_vector(2, addr, len, bi->pubkey_hash_chirp) < 0) |
| 988 | return -1; |
| 989 | wpa_hexdump(MSG_DEBUG, "DPP: Public key hash (chirp)", |
| 990 | bi->pubkey_hash_chirp, SHA256_MAC_LEN); |
| 991 | |
| 992 | return 0; |
| 993 | } |
| 994 | |
| 995 | |
| 996 | int dpp_get_subject_public_key(struct dpp_bootstrap_info *bi, |
| 997 | const u8 *data, size_t data_len) |
| 998 | { |
| 999 | EVP_PKEY *pkey; |
| 1000 | const unsigned char *p; |
| 1001 | int res; |
| 1002 | X509_PUBKEY *pub = NULL; |
| 1003 | ASN1_OBJECT *ppkalg; |
| 1004 | const unsigned char *pk; |
| 1005 | int ppklen; |
| 1006 | X509_ALGOR *pa; |
| 1007 | #if OPENSSL_VERSION_NUMBER < 0x10100000L || \ |
| 1008 | (defined(LIBRESSL_VERSION_NUMBER) && \ |
| 1009 | LIBRESSL_VERSION_NUMBER < 0x20800000L) |
| 1010 | ASN1_OBJECT *pa_oid; |
| 1011 | #else |
| 1012 | const ASN1_OBJECT *pa_oid; |
| 1013 | #endif |
| 1014 | const void *pval; |
| 1015 | int ptype; |
| 1016 | const ASN1_OBJECT *poid; |
| 1017 | char buf[100]; |
| 1018 | |
| 1019 | if (dpp_bi_pubkey_hash(bi, data, data_len) < 0) { |
| 1020 | wpa_printf(MSG_DEBUG, "DPP: Failed to hash public key"); |
| 1021 | return -1; |
| 1022 | } |
| 1023 | |
| 1024 | /* DER encoded ASN.1 SubjectPublicKeyInfo |
| 1025 | * |
| 1026 | * SubjectPublicKeyInfo ::= SEQUENCE { |
| 1027 | * algorithm AlgorithmIdentifier, |
| 1028 | * subjectPublicKey BIT STRING } |
| 1029 | * |
| 1030 | * AlgorithmIdentifier ::= SEQUENCE { |
| 1031 | * algorithm OBJECT IDENTIFIER, |
| 1032 | * parameters ANY DEFINED BY algorithm OPTIONAL } |
| 1033 | * |
| 1034 | * subjectPublicKey = compressed format public key per ANSI X9.63 |
| 1035 | * algorithm = ecPublicKey (1.2.840.10045.2.1) |
| 1036 | * parameters = shall be present and shall be OBJECT IDENTIFIER; e.g., |
| 1037 | * prime256v1 (1.2.840.10045.3.1.7) |
| 1038 | */ |
| 1039 | |
| 1040 | p = data; |
| 1041 | pkey = d2i_PUBKEY(NULL, &p, data_len); |
| 1042 | |
| 1043 | if (!pkey) { |
| 1044 | wpa_printf(MSG_DEBUG, |
| 1045 | "DPP: Could not parse URI public-key SubjectPublicKeyInfo"); |
| 1046 | return -1; |
| 1047 | } |
| 1048 | |
| 1049 | if (EVP_PKEY_type(EVP_PKEY_id(pkey)) != EVP_PKEY_EC) { |
| 1050 | wpa_printf(MSG_DEBUG, |
| 1051 | "DPP: SubjectPublicKeyInfo does not describe an EC key"); |
| 1052 | EVP_PKEY_free(pkey); |
| 1053 | return -1; |
| 1054 | } |
| 1055 | |
| 1056 | res = X509_PUBKEY_set(&pub, pkey); |
| 1057 | if (res != 1) { |
| 1058 | wpa_printf(MSG_DEBUG, "DPP: Could not set pubkey"); |
| 1059 | goto fail; |
| 1060 | } |
| 1061 | |
| 1062 | res = X509_PUBKEY_get0_param(&ppkalg, &pk, &ppklen, &pa, pub); |
| 1063 | if (res != 1) { |
| 1064 | wpa_printf(MSG_DEBUG, |
| 1065 | "DPP: Could not extract SubjectPublicKeyInfo parameters"); |
| 1066 | goto fail; |
| 1067 | } |
| 1068 | res = OBJ_obj2txt(buf, sizeof(buf), ppkalg, 0); |
| 1069 | if (res < 0 || (size_t) res >= sizeof(buf)) { |
| 1070 | wpa_printf(MSG_DEBUG, |
| 1071 | "DPP: Could not extract SubjectPublicKeyInfo algorithm"); |
| 1072 | goto fail; |
| 1073 | } |
| 1074 | wpa_printf(MSG_DEBUG, "DPP: URI subjectPublicKey algorithm: %s", buf); |
| 1075 | if (os_strcmp(buf, "id-ecPublicKey") != 0) { |
| 1076 | wpa_printf(MSG_DEBUG, |
| 1077 | "DPP: Unsupported SubjectPublicKeyInfo algorithm"); |
| 1078 | goto fail; |
| 1079 | } |
| 1080 | |
| 1081 | X509_ALGOR_get0(&pa_oid, &ptype, (void *) &pval, pa); |
| 1082 | if (ptype != V_ASN1_OBJECT) { |
| 1083 | wpa_printf(MSG_DEBUG, |
| 1084 | "DPP: SubjectPublicKeyInfo parameters did not contain an OID"); |
| 1085 | goto fail; |
| 1086 | } |
| 1087 | poid = pval; |
| 1088 | res = OBJ_obj2txt(buf, sizeof(buf), poid, 0); |
| 1089 | if (res < 0 || (size_t) res >= sizeof(buf)) { |
| 1090 | wpa_printf(MSG_DEBUG, |
| 1091 | "DPP: Could not extract SubjectPublicKeyInfo parameters OID"); |
| 1092 | goto fail; |
| 1093 | } |
| 1094 | wpa_printf(MSG_DEBUG, "DPP: URI subjectPublicKey parameters: %s", buf); |
| 1095 | bi->curve = dpp_get_curve_oid(poid); |
| 1096 | if (!bi->curve) { |
| 1097 | wpa_printf(MSG_DEBUG, |
| 1098 | "DPP: Unsupported SubjectPublicKeyInfo curve: %s", |
| 1099 | buf); |
| 1100 | goto fail; |
| 1101 | } |
| 1102 | |
| 1103 | wpa_hexdump(MSG_DEBUG, "DPP: URI subjectPublicKey", pk, ppklen); |
| 1104 | |
| 1105 | X509_PUBKEY_free(pub); |
| 1106 | bi->pubkey = pkey; |
| 1107 | return 0; |
| 1108 | fail: |
| 1109 | X509_PUBKEY_free(pub); |
| 1110 | EVP_PKEY_free(pkey); |
| 1111 | return -1; |
| 1112 | } |
| 1113 | |
| 1114 | |
| 1115 | static struct wpabuf * |
| 1116 | dpp_parse_jws_prot_hdr(const struct dpp_curve_params *curve, |
| 1117 | const u8 *prot_hdr, u16 prot_hdr_len, |
| 1118 | const EVP_MD **ret_md) |
| 1119 | { |
| 1120 | struct json_token *root, *token; |
| 1121 | struct wpabuf *kid = NULL; |
| 1122 | |
| 1123 | root = json_parse((const char *) prot_hdr, prot_hdr_len); |
| 1124 | if (!root) { |
| 1125 | wpa_printf(MSG_DEBUG, |
| 1126 | "DPP: JSON parsing failed for JWS Protected Header"); |
| 1127 | goto fail; |
| 1128 | } |
| 1129 | |
| 1130 | if (root->type != JSON_OBJECT) { |
| 1131 | wpa_printf(MSG_DEBUG, |
| 1132 | "DPP: JWS Protected Header root is not an object"); |
| 1133 | goto fail; |
| 1134 | } |
| 1135 | |
| 1136 | token = json_get_member(root, "typ"); |
| 1137 | if (!token || token->type != JSON_STRING) { |
| 1138 | wpa_printf(MSG_DEBUG, "DPP: No typ string value found"); |
| 1139 | goto fail; |
| 1140 | } |
| 1141 | wpa_printf(MSG_DEBUG, "DPP: JWS Protected Header typ=%s", |
| 1142 | token->string); |
| 1143 | if (os_strcmp(token->string, "dppCon") != 0) { |
| 1144 | wpa_printf(MSG_DEBUG, |
| 1145 | "DPP: Unsupported JWS Protected Header typ=%s", |
| 1146 | token->string); |
| 1147 | goto fail; |
| 1148 | } |
| 1149 | |
| 1150 | token = json_get_member(root, "alg"); |
| 1151 | if (!token || token->type != JSON_STRING) { |
| 1152 | wpa_printf(MSG_DEBUG, "DPP: No alg string value found"); |
| 1153 | goto fail; |
| 1154 | } |
| 1155 | wpa_printf(MSG_DEBUG, "DPP: JWS Protected Header alg=%s", |
| 1156 | token->string); |
| 1157 | if (os_strcmp(token->string, curve->jws_alg) != 0) { |
| 1158 | wpa_printf(MSG_DEBUG, |
| 1159 | "DPP: Unexpected JWS Protected Header alg=%s (expected %s based on C-sign-key)", |
| 1160 | token->string, curve->jws_alg); |
| 1161 | goto fail; |
| 1162 | } |
| 1163 | if (os_strcmp(token->string, "ES256") == 0 || |
| 1164 | os_strcmp(token->string, "BS256") == 0) |
| 1165 | *ret_md = EVP_sha256(); |
| 1166 | else if (os_strcmp(token->string, "ES384") == 0 || |
| 1167 | os_strcmp(token->string, "BS384") == 0) |
| 1168 | *ret_md = EVP_sha384(); |
| 1169 | else if (os_strcmp(token->string, "ES512") == 0 || |
| 1170 | os_strcmp(token->string, "BS512") == 0) |
| 1171 | *ret_md = EVP_sha512(); |
| 1172 | else |
| 1173 | *ret_md = NULL; |
| 1174 | if (!*ret_md) { |
| 1175 | wpa_printf(MSG_DEBUG, |
| 1176 | "DPP: Unsupported JWS Protected Header alg=%s", |
| 1177 | token->string); |
| 1178 | goto fail; |
| 1179 | } |
| 1180 | |
| 1181 | kid = json_get_member_base64url(root, "kid"); |
| 1182 | if (!kid) { |
| 1183 | wpa_printf(MSG_DEBUG, "DPP: No kid string value found"); |
| 1184 | goto fail; |
| 1185 | } |
| 1186 | wpa_hexdump_buf(MSG_DEBUG, "DPP: JWS Protected Header kid (decoded)", |
| 1187 | kid); |
| 1188 | |
| 1189 | fail: |
| 1190 | json_free(root); |
| 1191 | return kid; |
| 1192 | } |
| 1193 | |
| 1194 | |
| 1195 | static int dpp_check_pubkey_match(EVP_PKEY *pub, struct wpabuf *r_hash) |
| 1196 | { |
| 1197 | struct wpabuf *uncomp; |
| 1198 | int res; |
| 1199 | u8 hash[SHA256_MAC_LEN]; |
| 1200 | const u8 *addr[1]; |
| 1201 | size_t len[1]; |
| 1202 | |
| 1203 | if (wpabuf_len(r_hash) != SHA256_MAC_LEN) |
| 1204 | return -1; |
| 1205 | uncomp = dpp_get_pubkey_point(pub, 1); |
| 1206 | if (!uncomp) |
| 1207 | return -1; |
| 1208 | addr[0] = wpabuf_head(uncomp); |
| 1209 | len[0] = wpabuf_len(uncomp); |
| 1210 | wpa_hexdump(MSG_DEBUG, "DPP: Uncompressed public key", |
| 1211 | addr[0], len[0]); |
| 1212 | res = sha256_vector(1, addr, len, hash); |
| 1213 | wpabuf_free(uncomp); |
| 1214 | if (res < 0) |
| 1215 | return -1; |
| 1216 | if (os_memcmp(hash, wpabuf_head(r_hash), SHA256_MAC_LEN) != 0) { |
| 1217 | wpa_printf(MSG_DEBUG, |
| 1218 | "DPP: Received hash value does not match calculated public key hash value"); |
| 1219 | wpa_hexdump(MSG_DEBUG, "DPP: Calculated hash", |
| 1220 | hash, SHA256_MAC_LEN); |
| 1221 | return -1; |
| 1222 | } |
| 1223 | return 0; |
| 1224 | } |
| 1225 | |
| 1226 | |
| 1227 | enum dpp_status_error |
| 1228 | dpp_process_signed_connector(struct dpp_signed_connector_info *info, |
| 1229 | EVP_PKEY *csign_pub, const char *connector) |
| 1230 | { |
| 1231 | enum dpp_status_error ret = 255; |
| 1232 | const char *pos, *end, *signed_start, *signed_end; |
| 1233 | struct wpabuf *kid = NULL; |
| 1234 | unsigned char *prot_hdr = NULL, *signature = NULL; |
| 1235 | size_t prot_hdr_len = 0, signature_len = 0; |
| 1236 | const EVP_MD *sign_md = NULL; |
| 1237 | unsigned char *der = NULL; |
| 1238 | int der_len; |
| 1239 | int res; |
| 1240 | EVP_MD_CTX *md_ctx = NULL; |
| 1241 | ECDSA_SIG *sig = NULL; |
| 1242 | BIGNUM *r = NULL, *s = NULL; |
| 1243 | const struct dpp_curve_params *curve; |
| 1244 | const EC_KEY *eckey; |
| 1245 | const EC_GROUP *group; |
| 1246 | int nid; |
| 1247 | |
| 1248 | eckey = EVP_PKEY_get0_EC_KEY(csign_pub); |
| 1249 | if (!eckey) |
| 1250 | goto fail; |
| 1251 | group = EC_KEY_get0_group(eckey); |
| 1252 | if (!group) |
| 1253 | goto fail; |
| 1254 | nid = EC_GROUP_get_curve_name(group); |
| 1255 | curve = dpp_get_curve_nid(nid); |
| 1256 | if (!curve) |
| 1257 | goto fail; |
| 1258 | wpa_printf(MSG_DEBUG, "DPP: C-sign-key group: %s", curve->jwk_crv); |
| 1259 | os_memset(info, 0, sizeof(*info)); |
| 1260 | |
| 1261 | signed_start = pos = connector; |
| 1262 | end = os_strchr(pos, '.'); |
| 1263 | if (!end) { |
| 1264 | wpa_printf(MSG_DEBUG, "DPP: Missing dot(1) in signedConnector"); |
| 1265 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1266 | goto fail; |
| 1267 | } |
| 1268 | prot_hdr = base64_url_decode(pos, end - pos, &prot_hdr_len); |
| 1269 | if (!prot_hdr) { |
| 1270 | wpa_printf(MSG_DEBUG, |
| 1271 | "DPP: Failed to base64url decode signedConnector JWS Protected Header"); |
| 1272 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1273 | goto fail; |
| 1274 | } |
| 1275 | wpa_hexdump_ascii(MSG_DEBUG, |
| 1276 | "DPP: signedConnector - JWS Protected Header", |
| 1277 | prot_hdr, prot_hdr_len); |
| 1278 | kid = dpp_parse_jws_prot_hdr(curve, prot_hdr, prot_hdr_len, &sign_md); |
| 1279 | if (!kid) { |
| 1280 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1281 | goto fail; |
| 1282 | } |
| 1283 | if (wpabuf_len(kid) != SHA256_MAC_LEN) { |
| 1284 | wpa_printf(MSG_DEBUG, |
| 1285 | "DPP: Unexpected signedConnector JWS Protected Header kid length: %u (expected %u)", |
| 1286 | (unsigned int) wpabuf_len(kid), SHA256_MAC_LEN); |
| 1287 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1288 | goto fail; |
| 1289 | } |
| 1290 | |
| 1291 | pos = end + 1; |
| 1292 | end = os_strchr(pos, '.'); |
| 1293 | if (!end) { |
| 1294 | wpa_printf(MSG_DEBUG, |
| 1295 | "DPP: Missing dot(2) in signedConnector"); |
| 1296 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1297 | goto fail; |
| 1298 | } |
| 1299 | signed_end = end - 1; |
| 1300 | info->payload = base64_url_decode(pos, end - pos, &info->payload_len); |
| 1301 | if (!info->payload) { |
| 1302 | wpa_printf(MSG_DEBUG, |
| 1303 | "DPP: Failed to base64url decode signedConnector JWS Payload"); |
| 1304 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1305 | goto fail; |
| 1306 | } |
| 1307 | wpa_hexdump_ascii(MSG_DEBUG, |
| 1308 | "DPP: signedConnector - JWS Payload", |
| 1309 | info->payload, info->payload_len); |
| 1310 | pos = end + 1; |
| 1311 | signature = base64_url_decode(pos, os_strlen(pos), &signature_len); |
| 1312 | if (!signature) { |
| 1313 | wpa_printf(MSG_DEBUG, |
| 1314 | "DPP: Failed to base64url decode signedConnector signature"); |
| 1315 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1316 | goto fail; |
| 1317 | } |
| 1318 | wpa_hexdump(MSG_DEBUG, "DPP: signedConnector - signature", |
| 1319 | signature, signature_len); |
| 1320 | |
| 1321 | if (dpp_check_pubkey_match(csign_pub, kid) < 0) { |
| 1322 | ret = DPP_STATUS_NO_MATCH; |
| 1323 | goto fail; |
| 1324 | } |
| 1325 | |
| 1326 | if (signature_len & 0x01) { |
| 1327 | wpa_printf(MSG_DEBUG, |
| 1328 | "DPP: Unexpected signedConnector signature length (%d)", |
| 1329 | (int) signature_len); |
| 1330 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1331 | goto fail; |
| 1332 | } |
| 1333 | |
| 1334 | /* JWS Signature encodes the signature (r,s) as two octet strings. Need |
| 1335 | * to convert that to DER encoded ECDSA_SIG for OpenSSL EVP routines. */ |
| 1336 | r = BN_bin2bn(signature, signature_len / 2, NULL); |
| 1337 | s = BN_bin2bn(signature + signature_len / 2, signature_len / 2, NULL); |
| 1338 | sig = ECDSA_SIG_new(); |
| 1339 | if (!r || !s || !sig || ECDSA_SIG_set0(sig, r, s) != 1) |
| 1340 | goto fail; |
| 1341 | r = NULL; |
| 1342 | s = NULL; |
| 1343 | |
| 1344 | der_len = i2d_ECDSA_SIG(sig, &der); |
| 1345 | if (der_len <= 0) { |
| 1346 | wpa_printf(MSG_DEBUG, "DPP: Could not DER encode signature"); |
| 1347 | goto fail; |
| 1348 | } |
| 1349 | wpa_hexdump(MSG_DEBUG, "DPP: DER encoded signature", der, der_len); |
| 1350 | md_ctx = EVP_MD_CTX_create(); |
| 1351 | if (!md_ctx) |
| 1352 | goto fail; |
| 1353 | |
| 1354 | ERR_clear_error(); |
| 1355 | if (EVP_DigestVerifyInit(md_ctx, NULL, sign_md, NULL, csign_pub) != 1) { |
| 1356 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestVerifyInit failed: %s", |
| 1357 | ERR_error_string(ERR_get_error(), NULL)); |
| 1358 | goto fail; |
| 1359 | } |
| 1360 | if (EVP_DigestVerifyUpdate(md_ctx, signed_start, |
| 1361 | signed_end - signed_start + 1) != 1) { |
| 1362 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestVerifyUpdate failed: %s", |
| 1363 | ERR_error_string(ERR_get_error(), NULL)); |
| 1364 | goto fail; |
| 1365 | } |
| 1366 | res = EVP_DigestVerifyFinal(md_ctx, der, der_len); |
| 1367 | if (res != 1) { |
| 1368 | wpa_printf(MSG_DEBUG, |
| 1369 | "DPP: EVP_DigestVerifyFinal failed (res=%d): %s", |
| 1370 | res, ERR_error_string(ERR_get_error(), NULL)); |
| 1371 | ret = DPP_STATUS_INVALID_CONNECTOR; |
| 1372 | goto fail; |
| 1373 | } |
| 1374 | |
| 1375 | ret = DPP_STATUS_OK; |
| 1376 | fail: |
| 1377 | EVP_MD_CTX_destroy(md_ctx); |
| 1378 | os_free(prot_hdr); |
| 1379 | wpabuf_free(kid); |
| 1380 | os_free(signature); |
| 1381 | ECDSA_SIG_free(sig); |
| 1382 | BN_free(r); |
| 1383 | BN_free(s); |
| 1384 | OPENSSL_free(der); |
| 1385 | return ret; |
| 1386 | } |
| 1387 | |
| 1388 | |
| 1389 | enum dpp_status_error |
| 1390 | dpp_check_signed_connector(struct dpp_signed_connector_info *info, |
| 1391 | const u8 *csign_key, size_t csign_key_len, |
| 1392 | const u8 *peer_connector, size_t peer_connector_len) |
| 1393 | { |
| 1394 | const unsigned char *p; |
| 1395 | EVP_PKEY *csign = NULL; |
| 1396 | char *signed_connector = NULL; |
| 1397 | enum dpp_status_error res = DPP_STATUS_INVALID_CONNECTOR; |
| 1398 | |
| 1399 | p = csign_key; |
| 1400 | csign = d2i_PUBKEY(NULL, &p, csign_key_len); |
| 1401 | if (!csign) { |
| 1402 | wpa_printf(MSG_ERROR, |
| 1403 | "DPP: Failed to parse local C-sign-key information"); |
| 1404 | goto fail; |
| 1405 | } |
| 1406 | |
| 1407 | wpa_hexdump_ascii(MSG_DEBUG, "DPP: Peer signedConnector", |
| 1408 | peer_connector, peer_connector_len); |
| 1409 | signed_connector = os_malloc(peer_connector_len + 1); |
| 1410 | if (!signed_connector) |
| 1411 | goto fail; |
| 1412 | os_memcpy(signed_connector, peer_connector, peer_connector_len); |
| 1413 | signed_connector[peer_connector_len] = '\0'; |
| 1414 | res = dpp_process_signed_connector(info, csign, signed_connector); |
| 1415 | fail: |
| 1416 | os_free(signed_connector); |
| 1417 | EVP_PKEY_free(csign); |
| 1418 | return res; |
| 1419 | } |
| 1420 | |
| 1421 | |
| 1422 | int dpp_gen_r_auth(struct dpp_authentication *auth, u8 *r_auth) |
| 1423 | { |
| 1424 | struct wpabuf *pix, *prx, *bix, *brx; |
| 1425 | const u8 *addr[7]; |
| 1426 | size_t len[7]; |
| 1427 | size_t i, num_elem = 0; |
| 1428 | size_t nonce_len; |
| 1429 | u8 zero = 0; |
| 1430 | int res = -1; |
| 1431 | |
| 1432 | /* R-auth = H(I-nonce | R-nonce | PI.x | PR.x | [BI.x |] BR.x | 0) */ |
| 1433 | nonce_len = auth->curve->nonce_len; |
| 1434 | |
| 1435 | if (auth->initiator) { |
| 1436 | pix = dpp_get_pubkey_point(auth->own_protocol_key, 0); |
| 1437 | prx = dpp_get_pubkey_point(auth->peer_protocol_key, 0); |
| 1438 | if (auth->own_bi) |
| 1439 | bix = dpp_get_pubkey_point(auth->own_bi->pubkey, 0); |
| 1440 | else |
| 1441 | bix = NULL; |
| 1442 | brx = dpp_get_pubkey_point(auth->peer_bi->pubkey, 0); |
| 1443 | } else { |
| 1444 | pix = dpp_get_pubkey_point(auth->peer_protocol_key, 0); |
| 1445 | prx = dpp_get_pubkey_point(auth->own_protocol_key, 0); |
| 1446 | if (auth->peer_bi) |
| 1447 | bix = dpp_get_pubkey_point(auth->peer_bi->pubkey, 0); |
| 1448 | else |
| 1449 | bix = NULL; |
| 1450 | brx = dpp_get_pubkey_point(auth->own_bi->pubkey, 0); |
| 1451 | } |
| 1452 | if (!pix || !prx || !brx) |
| 1453 | goto fail; |
| 1454 | |
| 1455 | addr[num_elem] = auth->i_nonce; |
| 1456 | len[num_elem] = nonce_len; |
| 1457 | num_elem++; |
| 1458 | |
| 1459 | addr[num_elem] = auth->r_nonce; |
| 1460 | len[num_elem] = nonce_len; |
| 1461 | num_elem++; |
| 1462 | |
| 1463 | addr[num_elem] = wpabuf_head(pix); |
| 1464 | len[num_elem] = wpabuf_len(pix) / 2; |
| 1465 | num_elem++; |
| 1466 | |
| 1467 | addr[num_elem] = wpabuf_head(prx); |
| 1468 | len[num_elem] = wpabuf_len(prx) / 2; |
| 1469 | num_elem++; |
| 1470 | |
| 1471 | if (bix) { |
| 1472 | addr[num_elem] = wpabuf_head(bix); |
| 1473 | len[num_elem] = wpabuf_len(bix) / 2; |
| 1474 | num_elem++; |
| 1475 | } |
| 1476 | |
| 1477 | addr[num_elem] = wpabuf_head(brx); |
| 1478 | len[num_elem] = wpabuf_len(brx) / 2; |
| 1479 | num_elem++; |
| 1480 | |
| 1481 | addr[num_elem] = &zero; |
| 1482 | len[num_elem] = 1; |
| 1483 | num_elem++; |
| 1484 | |
| 1485 | wpa_printf(MSG_DEBUG, "DPP: R-auth hash components"); |
| 1486 | for (i = 0; i < num_elem; i++) |
| 1487 | wpa_hexdump(MSG_DEBUG, "DPP: hash component", addr[i], len[i]); |
| 1488 | res = dpp_hash_vector(auth->curve, num_elem, addr, len, r_auth); |
| 1489 | if (res == 0) |
| 1490 | wpa_hexdump(MSG_DEBUG, "DPP: R-auth", r_auth, |
| 1491 | auth->curve->hash_len); |
| 1492 | fail: |
| 1493 | wpabuf_free(pix); |
| 1494 | wpabuf_free(prx); |
| 1495 | wpabuf_free(bix); |
| 1496 | wpabuf_free(brx); |
| 1497 | return res; |
| 1498 | } |
| 1499 | |
| 1500 | |
| 1501 | int dpp_gen_i_auth(struct dpp_authentication *auth, u8 *i_auth) |
| 1502 | { |
| 1503 | struct wpabuf *pix = NULL, *prx = NULL, *bix = NULL, *brx = NULL; |
| 1504 | const u8 *addr[7]; |
| 1505 | size_t len[7]; |
| 1506 | size_t i, num_elem = 0; |
| 1507 | size_t nonce_len; |
| 1508 | u8 one = 1; |
| 1509 | int res = -1; |
| 1510 | |
| 1511 | /* I-auth = H(R-nonce | I-nonce | PR.x | PI.x | BR.x | [BI.x |] 1) */ |
| 1512 | nonce_len = auth->curve->nonce_len; |
| 1513 | |
| 1514 | if (auth->initiator) { |
| 1515 | pix = dpp_get_pubkey_point(auth->own_protocol_key, 0); |
| 1516 | prx = dpp_get_pubkey_point(auth->peer_protocol_key, 0); |
| 1517 | if (auth->own_bi) |
| 1518 | bix = dpp_get_pubkey_point(auth->own_bi->pubkey, 0); |
| 1519 | else |
| 1520 | bix = NULL; |
| 1521 | if (!auth->peer_bi) |
| 1522 | goto fail; |
| 1523 | brx = dpp_get_pubkey_point(auth->peer_bi->pubkey, 0); |
| 1524 | } else { |
| 1525 | pix = dpp_get_pubkey_point(auth->peer_protocol_key, 0); |
| 1526 | prx = dpp_get_pubkey_point(auth->own_protocol_key, 0); |
| 1527 | if (auth->peer_bi) |
| 1528 | bix = dpp_get_pubkey_point(auth->peer_bi->pubkey, 0); |
| 1529 | else |
| 1530 | bix = NULL; |
| 1531 | if (!auth->own_bi) |
| 1532 | goto fail; |
| 1533 | brx = dpp_get_pubkey_point(auth->own_bi->pubkey, 0); |
| 1534 | } |
| 1535 | if (!pix || !prx || !brx) |
| 1536 | goto fail; |
| 1537 | |
| 1538 | addr[num_elem] = auth->r_nonce; |
| 1539 | len[num_elem] = nonce_len; |
| 1540 | num_elem++; |
| 1541 | |
| 1542 | addr[num_elem] = auth->i_nonce; |
| 1543 | len[num_elem] = nonce_len; |
| 1544 | num_elem++; |
| 1545 | |
| 1546 | addr[num_elem] = wpabuf_head(prx); |
| 1547 | len[num_elem] = wpabuf_len(prx) / 2; |
| 1548 | num_elem++; |
| 1549 | |
| 1550 | addr[num_elem] = wpabuf_head(pix); |
| 1551 | len[num_elem] = wpabuf_len(pix) / 2; |
| 1552 | num_elem++; |
| 1553 | |
| 1554 | addr[num_elem] = wpabuf_head(brx); |
| 1555 | len[num_elem] = wpabuf_len(brx) / 2; |
| 1556 | num_elem++; |
| 1557 | |
| 1558 | if (bix) { |
| 1559 | addr[num_elem] = wpabuf_head(bix); |
| 1560 | len[num_elem] = wpabuf_len(bix) / 2; |
| 1561 | num_elem++; |
| 1562 | } |
| 1563 | |
| 1564 | addr[num_elem] = &one; |
| 1565 | len[num_elem] = 1; |
| 1566 | num_elem++; |
| 1567 | |
| 1568 | wpa_printf(MSG_DEBUG, "DPP: I-auth hash components"); |
| 1569 | for (i = 0; i < num_elem; i++) |
| 1570 | wpa_hexdump(MSG_DEBUG, "DPP: hash component", addr[i], len[i]); |
| 1571 | res = dpp_hash_vector(auth->curve, num_elem, addr, len, i_auth); |
| 1572 | if (res == 0) |
| 1573 | wpa_hexdump(MSG_DEBUG, "DPP: I-auth", i_auth, |
| 1574 | auth->curve->hash_len); |
| 1575 | fail: |
| 1576 | wpabuf_free(pix); |
| 1577 | wpabuf_free(prx); |
| 1578 | wpabuf_free(bix); |
| 1579 | wpabuf_free(brx); |
| 1580 | return res; |
| 1581 | } |
| 1582 | |
| 1583 | |
| 1584 | int dpp_auth_derive_l_responder(struct dpp_authentication *auth) |
| 1585 | { |
| 1586 | const EC_GROUP *group; |
| 1587 | EC_POINT *l = NULL; |
| 1588 | const EC_KEY *BI, *bR, *pR; |
| 1589 | const EC_POINT *BI_point; |
| 1590 | BN_CTX *bnctx; |
| 1591 | BIGNUM *lx, *sum, *q; |
| 1592 | const BIGNUM *bR_bn, *pR_bn; |
| 1593 | int ret = -1; |
| 1594 | |
| 1595 | /* L = ((bR + pR) modulo q) * BI */ |
| 1596 | |
| 1597 | bnctx = BN_CTX_new(); |
| 1598 | sum = BN_new(); |
| 1599 | q = BN_new(); |
| 1600 | lx = BN_new(); |
| 1601 | if (!bnctx || !sum || !q || !lx) |
| 1602 | goto fail; |
| 1603 | BI = EVP_PKEY_get0_EC_KEY(auth->peer_bi->pubkey); |
| 1604 | if (!BI) |
| 1605 | goto fail; |
| 1606 | BI_point = EC_KEY_get0_public_key(BI); |
| 1607 | group = EC_KEY_get0_group(BI); |
| 1608 | if (!group) |
| 1609 | goto fail; |
| 1610 | |
| 1611 | bR = EVP_PKEY_get0_EC_KEY(auth->own_bi->pubkey); |
| 1612 | pR = EVP_PKEY_get0_EC_KEY(auth->own_protocol_key); |
| 1613 | if (!bR || !pR) |
| 1614 | goto fail; |
| 1615 | bR_bn = EC_KEY_get0_private_key(bR); |
| 1616 | pR_bn = EC_KEY_get0_private_key(pR); |
| 1617 | if (!bR_bn || !pR_bn) |
| 1618 | goto fail; |
| 1619 | if (EC_GROUP_get_order(group, q, bnctx) != 1 || |
| 1620 | BN_mod_add(sum, bR_bn, pR_bn, q, bnctx) != 1) |
| 1621 | goto fail; |
| 1622 | l = EC_POINT_new(group); |
| 1623 | if (!l || |
| 1624 | EC_POINT_mul(group, l, NULL, BI_point, sum, bnctx) != 1 || |
| 1625 | EC_POINT_get_affine_coordinates_GFp(group, l, lx, NULL, |
| 1626 | bnctx) != 1) { |
| 1627 | wpa_printf(MSG_ERROR, |
| 1628 | "OpenSSL: failed: %s", |
| 1629 | ERR_error_string(ERR_get_error(), NULL)); |
| 1630 | goto fail; |
| 1631 | } |
| 1632 | |
| 1633 | if (dpp_bn2bin_pad(lx, auth->Lx, auth->secret_len) < 0) |
| 1634 | goto fail; |
| 1635 | wpa_hexdump_key(MSG_DEBUG, "DPP: L.x", auth->Lx, auth->secret_len); |
| 1636 | auth->Lx_len = auth->secret_len; |
| 1637 | ret = 0; |
| 1638 | fail: |
| 1639 | EC_POINT_clear_free(l); |
| 1640 | BN_clear_free(lx); |
| 1641 | BN_clear_free(sum); |
| 1642 | BN_free(q); |
| 1643 | BN_CTX_free(bnctx); |
| 1644 | return ret; |
| 1645 | } |
| 1646 | |
| 1647 | |
| 1648 | int dpp_auth_derive_l_initiator(struct dpp_authentication *auth) |
| 1649 | { |
| 1650 | const EC_GROUP *group; |
| 1651 | EC_POINT *l = NULL, *sum = NULL; |
| 1652 | const EC_KEY *bI, *BR, *PR; |
| 1653 | const EC_POINT *BR_point, *PR_point; |
| 1654 | BN_CTX *bnctx; |
| 1655 | BIGNUM *lx; |
| 1656 | const BIGNUM *bI_bn; |
| 1657 | int ret = -1; |
| 1658 | |
| 1659 | /* L = bI * (BR + PR) */ |
| 1660 | |
| 1661 | bnctx = BN_CTX_new(); |
| 1662 | lx = BN_new(); |
| 1663 | if (!bnctx || !lx) |
| 1664 | goto fail; |
| 1665 | BR = EVP_PKEY_get0_EC_KEY(auth->peer_bi->pubkey); |
| 1666 | PR = EVP_PKEY_get0_EC_KEY(auth->peer_protocol_key); |
| 1667 | if (!BR || !PR) |
| 1668 | goto fail; |
| 1669 | BR_point = EC_KEY_get0_public_key(BR); |
| 1670 | PR_point = EC_KEY_get0_public_key(PR); |
| 1671 | |
| 1672 | bI = EVP_PKEY_get0_EC_KEY(auth->own_bi->pubkey); |
| 1673 | if (!bI) |
| 1674 | goto fail; |
| 1675 | group = EC_KEY_get0_group(bI); |
| 1676 | bI_bn = EC_KEY_get0_private_key(bI); |
| 1677 | if (!group || !bI_bn) |
| 1678 | goto fail; |
| 1679 | sum = EC_POINT_new(group); |
| 1680 | l = EC_POINT_new(group); |
| 1681 | if (!sum || !l || |
| 1682 | EC_POINT_add(group, sum, BR_point, PR_point, bnctx) != 1 || |
| 1683 | EC_POINT_mul(group, l, NULL, sum, bI_bn, bnctx) != 1 || |
| 1684 | EC_POINT_get_affine_coordinates_GFp(group, l, lx, NULL, |
| 1685 | bnctx) != 1) { |
| 1686 | wpa_printf(MSG_ERROR, |
| 1687 | "OpenSSL: failed: %s", |
| 1688 | ERR_error_string(ERR_get_error(), NULL)); |
| 1689 | goto fail; |
| 1690 | } |
| 1691 | |
| 1692 | if (dpp_bn2bin_pad(lx, auth->Lx, auth->secret_len) < 0) |
| 1693 | goto fail; |
| 1694 | wpa_hexdump_key(MSG_DEBUG, "DPP: L.x", auth->Lx, auth->secret_len); |
| 1695 | auth->Lx_len = auth->secret_len; |
| 1696 | ret = 0; |
| 1697 | fail: |
| 1698 | EC_POINT_clear_free(l); |
| 1699 | EC_POINT_clear_free(sum); |
| 1700 | BN_clear_free(lx); |
| 1701 | BN_CTX_free(bnctx); |
| 1702 | return ret; |
| 1703 | } |
| 1704 | |
| 1705 | |
| 1706 | int dpp_derive_pmk(const u8 *Nx, size_t Nx_len, u8 *pmk, unsigned int hash_len) |
| 1707 | { |
| 1708 | u8 salt[DPP_MAX_HASH_LEN], prk[DPP_MAX_HASH_LEN]; |
| 1709 | const char *info = "DPP PMK"; |
| 1710 | int res; |
| 1711 | |
| 1712 | /* PMK = HKDF(<>, "DPP PMK", N.x) */ |
| 1713 | |
| 1714 | /* HKDF-Extract(<>, N.x) */ |
| 1715 | os_memset(salt, 0, hash_len); |
| 1716 | if (dpp_hmac(hash_len, salt, hash_len, Nx, Nx_len, prk) < 0) |
| 1717 | return -1; |
| 1718 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK = HKDF-Extract(<>, IKM=N.x)", |
| 1719 | prk, hash_len); |
| 1720 | |
| 1721 | /* HKDF-Expand(PRK, info, L) */ |
| 1722 | res = dpp_hkdf_expand(hash_len, prk, hash_len, info, pmk, hash_len); |
| 1723 | os_memset(prk, 0, hash_len); |
| 1724 | if (res < 0) |
| 1725 | return -1; |
| 1726 | |
| 1727 | wpa_hexdump_key(MSG_DEBUG, "DPP: PMK = HKDF-Expand(PRK, info, L)", |
| 1728 | pmk, hash_len); |
| 1729 | return 0; |
| 1730 | } |
| 1731 | |
| 1732 | |
| 1733 | int dpp_derive_pmkid(const struct dpp_curve_params *curve, |
| 1734 | EVP_PKEY *own_key, EVP_PKEY *peer_key, u8 *pmkid) |
| 1735 | { |
| 1736 | struct wpabuf *nkx, *pkx; |
| 1737 | int ret = -1, res; |
| 1738 | const u8 *addr[2]; |
| 1739 | size_t len[2]; |
| 1740 | u8 hash[SHA256_MAC_LEN]; |
| 1741 | |
| 1742 | /* PMKID = Truncate-128(H(min(NK.x, PK.x) | max(NK.x, PK.x))) */ |
| 1743 | nkx = dpp_get_pubkey_point(own_key, 0); |
| 1744 | pkx = dpp_get_pubkey_point(peer_key, 0); |
| 1745 | if (!nkx || !pkx) |
| 1746 | goto fail; |
| 1747 | addr[0] = wpabuf_head(nkx); |
| 1748 | len[0] = wpabuf_len(nkx) / 2; |
| 1749 | addr[1] = wpabuf_head(pkx); |
| 1750 | len[1] = wpabuf_len(pkx) / 2; |
| 1751 | if (len[0] != len[1]) |
| 1752 | goto fail; |
| 1753 | if (os_memcmp(addr[0], addr[1], len[0]) > 0) { |
| 1754 | addr[0] = wpabuf_head(pkx); |
| 1755 | addr[1] = wpabuf_head(nkx); |
| 1756 | } |
| 1757 | wpa_hexdump(MSG_DEBUG, "DPP: PMKID hash payload 1", addr[0], len[0]); |
| 1758 | wpa_hexdump(MSG_DEBUG, "DPP: PMKID hash payload 2", addr[1], len[1]); |
| 1759 | res = sha256_vector(2, addr, len, hash); |
| 1760 | if (res < 0) |
| 1761 | goto fail; |
| 1762 | wpa_hexdump(MSG_DEBUG, "DPP: PMKID hash output", hash, SHA256_MAC_LEN); |
| 1763 | os_memcpy(pmkid, hash, PMKID_LEN); |
| 1764 | wpa_hexdump(MSG_DEBUG, "DPP: PMKID", pmkid, PMKID_LEN); |
| 1765 | ret = 0; |
| 1766 | fail: |
| 1767 | wpabuf_free(nkx); |
| 1768 | wpabuf_free(pkx); |
| 1769 | return ret; |
| 1770 | } |
| 1771 | |
| 1772 | |
| 1773 | /* Role-specific elements for PKEX */ |
| 1774 | |
| 1775 | /* NIST P-256 */ |
| 1776 | static const u8 pkex_init_x_p256[32] = { |
| 1777 | 0x56, 0x26, 0x12, 0xcf, 0x36, 0x48, 0xfe, 0x0b, |
| 1778 | 0x07, 0x04, 0xbb, 0x12, 0x22, 0x50, 0xb2, 0x54, |
| 1779 | 0xb1, 0x94, 0x64, 0x7e, 0x54, 0xce, 0x08, 0x07, |
| 1780 | 0x2e, 0xec, 0xca, 0x74, 0x5b, 0x61, 0x2d, 0x25 |
| 1781 | }; |
| 1782 | static const u8 pkex_init_y_p256[32] = { |
| 1783 | 0x3e, 0x44, 0xc7, 0xc9, 0x8c, 0x1c, 0xa1, 0x0b, |
| 1784 | 0x20, 0x09, 0x93, 0xb2, 0xfd, 0xe5, 0x69, 0xdc, |
| 1785 | 0x75, 0xbc, 0xad, 0x33, 0xc1, 0xe7, 0xc6, 0x45, |
| 1786 | 0x4d, 0x10, 0x1e, 0x6a, 0x3d, 0x84, 0x3c, 0xa4 |
| 1787 | }; |
| 1788 | static const u8 pkex_resp_x_p256[32] = { |
| 1789 | 0x1e, 0xa4, 0x8a, 0xb1, 0xa4, 0xe8, 0x42, 0x39, |
| 1790 | 0xad, 0x73, 0x07, 0xf2, 0x34, 0xdf, 0x57, 0x4f, |
| 1791 | 0xc0, 0x9d, 0x54, 0xbe, 0x36, 0x1b, 0x31, 0x0f, |
| 1792 | 0x59, 0x91, 0x52, 0x33, 0xac, 0x19, 0x9d, 0x76 |
| 1793 | }; |
| 1794 | static const u8 pkex_resp_y_p256[32] = { |
| 1795 | 0xd9, 0xfb, 0xf6, 0xb9, 0xf5, 0xfa, 0xdf, 0x19, |
| 1796 | 0x58, 0xd8, 0x3e, 0xc9, 0x89, 0x7a, 0x35, 0xc1, |
| 1797 | 0xbd, 0xe9, 0x0b, 0x77, 0x7a, 0xcb, 0x91, 0x2a, |
| 1798 | 0xe8, 0x21, 0x3f, 0x47, 0x52, 0x02, 0x4d, 0x67 |
| 1799 | }; |
| 1800 | |
| 1801 | /* NIST P-384 */ |
| 1802 | static const u8 pkex_init_x_p384[48] = { |
| 1803 | 0x95, 0x3f, 0x42, 0x9e, 0x50, 0x7f, 0xf9, 0xaa, |
| 1804 | 0xac, 0x1a, 0xf2, 0x85, 0x2e, 0x64, 0x91, 0x68, |
| 1805 | 0x64, 0xc4, 0x3c, 0xb7, 0x5c, 0xf8, 0xc9, 0x53, |
| 1806 | 0x6e, 0x58, 0x4c, 0x7f, 0xc4, 0x64, 0x61, 0xac, |
| 1807 | 0x51, 0x8a, 0x6f, 0xfe, 0xab, 0x74, 0xe6, 0x12, |
| 1808 | 0x81, 0xac, 0x38, 0x5d, 0x41, 0xe6, 0xb9, 0xa3 |
| 1809 | }; |
| 1810 | static const u8 pkex_init_y_p384[48] = { |
| 1811 | 0x76, 0x2f, 0x68, 0x84, 0xa6, 0xb0, 0x59, 0x29, |
| 1812 | 0x83, 0xa2, 0x6c, 0xa4, 0x6c, 0x3b, 0xf8, 0x56, |
| 1813 | 0x76, 0x11, 0x2a, 0x32, 0x90, 0xbd, 0x07, 0xc7, |
| 1814 | 0x37, 0x39, 0x9d, 0xdb, 0x96, 0xf3, 0x2b, 0xb6, |
| 1815 | 0x27, 0xbb, 0x29, 0x3c, 0x17, 0x33, 0x9d, 0x94, |
| 1816 | 0xc3, 0xda, 0xac, 0x46, 0xb0, 0x8e, 0x07, 0x18 |
| 1817 | }; |
| 1818 | static const u8 pkex_resp_x_p384[48] = { |
| 1819 | 0xad, 0xbe, 0xd7, 0x1d, 0x3a, 0x71, 0x64, 0x98, |
| 1820 | 0x5f, 0xb4, 0xd6, 0x4b, 0x50, 0xd0, 0x84, 0x97, |
| 1821 | 0x4b, 0x7e, 0x57, 0x70, 0xd2, 0xd9, 0xf4, 0x92, |
| 1822 | 0x2a, 0x3f, 0xce, 0x99, 0xc5, 0x77, 0x33, 0x44, |
| 1823 | 0x14, 0x56, 0x92, 0xcb, 0xae, 0x46, 0x64, 0xdf, |
| 1824 | 0xe0, 0xbb, 0xd7, 0xb1, 0x29, 0x20, 0x72, 0xdf |
| 1825 | }; |
| 1826 | static const u8 pkex_resp_y_p384[48] = { |
| 1827 | 0xab, 0xa7, 0xdf, 0x52, 0xaa, 0xe2, 0x35, 0x0c, |
| 1828 | 0xe3, 0x75, 0x32, 0xe6, 0xbf, 0x06, 0xc8, 0x7c, |
| 1829 | 0x38, 0x29, 0x4c, 0xec, 0x82, 0xac, 0xd7, 0xa3, |
| 1830 | 0x09, 0xd2, 0x0e, 0x22, 0x5a, 0x74, 0x52, 0xa1, |
| 1831 | 0x7e, 0x54, 0x4e, 0xfe, 0xc6, 0x29, 0x33, 0x63, |
| 1832 | 0x15, 0xe1, 0x7b, 0xe3, 0x40, 0x1c, 0xca, 0x06 |
| 1833 | }; |
| 1834 | |
| 1835 | /* NIST P-521 */ |
| 1836 | static const u8 pkex_init_x_p521[66] = { |
| 1837 | 0x00, 0x16, 0x20, 0x45, 0x19, 0x50, 0x95, 0x23, |
| 1838 | 0x0d, 0x24, 0xbe, 0x00, 0x87, 0xdc, 0xfa, 0xf0, |
| 1839 | 0x58, 0x9a, 0x01, 0x60, 0x07, 0x7a, 0xca, 0x76, |
| 1840 | 0x01, 0xab, 0x2d, 0x5a, 0x46, 0xcd, 0x2c, 0xb5, |
| 1841 | 0x11, 0x9a, 0xff, 0xaa, 0x48, 0x04, 0x91, 0x38, |
| 1842 | 0xcf, 0x86, 0xfc, 0xa4, 0xa5, 0x0f, 0x47, 0x01, |
| 1843 | 0x80, 0x1b, 0x30, 0xa3, 0xae, 0xe8, 0x1c, 0x2e, |
| 1844 | 0xea, 0xcc, 0xf0, 0x03, 0x9f, 0x77, 0x4c, 0x8d, |
| 1845 | 0x97, 0x76 |
| 1846 | }; |
| 1847 | static const u8 pkex_init_y_p521[66] = { |
| 1848 | 0x00, 0xb3, 0x8e, 0x02, 0xe4, 0x2a, 0x63, 0x59, |
| 1849 | 0x12, 0xc6, 0x10, 0xba, 0x3a, 0xf9, 0x02, 0x99, |
| 1850 | 0x3f, 0x14, 0xf0, 0x40, 0xde, 0x5c, 0xc9, 0x8b, |
| 1851 | 0x02, 0x55, 0xfa, 0x91, 0xb1, 0xcc, 0x6a, 0xbd, |
| 1852 | 0xe5, 0x62, 0xc0, 0xc5, 0xe3, 0xa1, 0x57, 0x9f, |
| 1853 | 0x08, 0x1a, 0xa6, 0xe2, 0xf8, 0x55, 0x90, 0xbf, |
| 1854 | 0xf5, 0xa6, 0xc3, 0xd8, 0x52, 0x1f, 0xb7, 0x02, |
| 1855 | 0x2e, 0x7c, 0xc8, 0xb3, 0x20, 0x1e, 0x79, 0x8d, |
| 1856 | 0x03, 0xa8 |
| 1857 | }; |
| 1858 | static const u8 pkex_resp_x_p521[66] = { |
| 1859 | 0x00, 0x79, 0xe4, 0x4d, 0x6b, 0x5e, 0x12, 0x0a, |
| 1860 | 0x18, 0x2c, 0xb3, 0x05, 0x77, 0x0f, 0xc3, 0x44, |
| 1861 | 0x1a, 0xcd, 0x78, 0x46, 0x14, 0xee, 0x46, 0x3f, |
| 1862 | 0xab, 0xc9, 0x59, 0x7c, 0x85, 0xa0, 0xc2, 0xfb, |
| 1863 | 0x02, 0x32, 0x99, 0xde, 0x5d, 0xe1, 0x0d, 0x48, |
| 1864 | 0x2d, 0x71, 0x7d, 0x8d, 0x3f, 0x61, 0x67, 0x9e, |
| 1865 | 0x2b, 0x8b, 0x12, 0xde, 0x10, 0x21, 0x55, 0x0a, |
| 1866 | 0x5b, 0x2d, 0xe8, 0x05, 0x09, 0xf6, 0x20, 0x97, |
| 1867 | 0x84, 0xb4 |
| 1868 | }; |
| 1869 | static const u8 pkex_resp_y_p521[66] = { |
| 1870 | 0x00, 0x46, 0x63, 0x39, 0xbe, 0xcd, 0xa4, 0x2d, |
| 1871 | 0xca, 0x27, 0x74, 0xd4, 0x1b, 0x91, 0x33, 0x20, |
| 1872 | 0x83, 0xc7, 0x3b, 0xa4, 0x09, 0x8b, 0x8e, 0xa3, |
| 1873 | 0x88, 0xe9, 0x75, 0x7f, 0x56, 0x7b, 0x38, 0x84, |
| 1874 | 0x62, 0x02, 0x7c, 0x90, 0x51, 0x07, 0xdb, 0xe9, |
| 1875 | 0xd0, 0xde, 0xda, 0x9a, 0x5d, 0xe5, 0x94, 0xd2, |
| 1876 | 0xcf, 0x9d, 0x4c, 0x33, 0x91, 0xa6, 0xc3, 0x80, |
| 1877 | 0xa7, 0x6e, 0x7e, 0x8d, 0xf8, 0x73, 0x6e, 0x53, |
| 1878 | 0xce, 0xe1 |
| 1879 | }; |
| 1880 | |
| 1881 | /* Brainpool P-256r1 */ |
| 1882 | static const u8 pkex_init_x_bp_p256r1[32] = { |
| 1883 | 0x46, 0x98, 0x18, 0x6c, 0x27, 0xcd, 0x4b, 0x10, |
| 1884 | 0x7d, 0x55, 0xa3, 0xdd, 0x89, 0x1f, 0x9f, 0xca, |
| 1885 | 0xc7, 0x42, 0x5b, 0x8a, 0x23, 0xed, 0xf8, 0x75, |
| 1886 | 0xac, 0xc7, 0xe9, 0x8d, 0xc2, 0x6f, 0xec, 0xd8 |
| 1887 | }; |
| 1888 | static const u8 pkex_init_y_bp_p256r1[32] = { |
| 1889 | 0x93, 0xca, 0xef, 0xa9, 0x66, 0x3e, 0x87, 0xcd, |
| 1890 | 0x52, 0x6e, 0x54, 0x13, 0xef, 0x31, 0x67, 0x30, |
| 1891 | 0x15, 0x13, 0x9d, 0x6d, 0xc0, 0x95, 0x32, 0xbe, |
| 1892 | 0x4f, 0xab, 0x5d, 0xf7, 0xbf, 0x5e, 0xaa, 0x0b |
| 1893 | }; |
| 1894 | static const u8 pkex_resp_x_bp_p256r1[32] = { |
| 1895 | 0x90, 0x18, 0x84, 0xc9, 0xdc, 0xcc, 0xb5, 0x2f, |
| 1896 | 0x4a, 0x3f, 0x4f, 0x18, 0x0a, 0x22, 0x56, 0x6a, |
| 1897 | 0xa9, 0xef, 0xd4, 0xe6, 0xc3, 0x53, 0xc2, 0x1a, |
| 1898 | 0x23, 0x54, 0xdd, 0x08, 0x7e, 0x10, 0xd8, 0xe3 |
| 1899 | }; |
| 1900 | static const u8 pkex_resp_y_bp_p256r1[32] = { |
| 1901 | 0x2a, 0xfa, 0x98, 0x9b, 0xe3, 0xda, 0x30, 0xfd, |
| 1902 | 0x32, 0x28, 0xcb, 0x66, 0xfb, 0x40, 0x7f, 0xf2, |
| 1903 | 0xb2, 0x25, 0x80, 0x82, 0x44, 0x85, 0x13, 0x7e, |
| 1904 | 0x4b, 0xb5, 0x06, 0xc0, 0x03, 0x69, 0x23, 0x64 |
| 1905 | }; |
| 1906 | |
| 1907 | /* Brainpool P-384r1 */ |
| 1908 | static const u8 pkex_init_x_bp_p384r1[48] = { |
| 1909 | 0x0a, 0x2c, 0xeb, 0x49, 0x5e, 0xb7, 0x23, 0xbd, |
| 1910 | 0x20, 0x5b, 0xe0, 0x49, 0xdf, 0xcf, 0xcf, 0x19, |
| 1911 | 0x37, 0x36, 0xe1, 0x2f, 0x59, 0xdb, 0x07, 0x06, |
| 1912 | 0xb5, 0xeb, 0x2d, 0xae, 0xc2, 0xb2, 0x38, 0x62, |
| 1913 | 0xa6, 0x73, 0x09, 0xa0, 0x6c, 0x0a, 0xa2, 0x30, |
| 1914 | 0x99, 0xeb, 0xf7, 0x1e, 0x47, 0xb9, 0x5e, 0xbe |
| 1915 | }; |
| 1916 | static const u8 pkex_init_y_bp_p384r1[48] = { |
| 1917 | 0x54, 0x76, 0x61, 0x65, 0x75, 0x5a, 0x2f, 0x99, |
| 1918 | 0x39, 0x73, 0xca, 0x6c, 0xf9, 0xf7, 0x12, 0x86, |
| 1919 | 0x54, 0xd5, 0xd4, 0xad, 0x45, 0x7b, 0xbf, 0x32, |
| 1920 | 0xee, 0x62, 0x8b, 0x9f, 0x52, 0xe8, 0xa0, 0xc9, |
| 1921 | 0xb7, 0x9d, 0xd1, 0x09, 0xb4, 0x79, 0x1c, 0x3e, |
| 1922 | 0x1a, 0xbf, 0x21, 0x45, 0x66, 0x6b, 0x02, 0x52 |
| 1923 | }; |
| 1924 | static const u8 pkex_resp_x_bp_p384r1[48] = { |
| 1925 | 0x03, 0xa2, 0x57, 0xef, 0xe8, 0x51, 0x21, 0xa0, |
| 1926 | 0xc8, 0x9e, 0x21, 0x02, 0xb5, 0x9a, 0x36, 0x25, |
| 1927 | 0x74, 0x22, 0xd1, 0xf2, 0x1b, 0xa8, 0x9a, 0x9b, |
| 1928 | 0x97, 0xbc, 0x5a, 0xeb, 0x26, 0x15, 0x09, 0x71, |
| 1929 | 0x77, 0x59, 0xec, 0x8b, 0xb7, 0xe1, 0xe8, 0xce, |
| 1930 | 0x65, 0xb8, 0xaf, 0xf8, 0x80, 0xae, 0x74, 0x6c |
| 1931 | }; |
| 1932 | static const u8 pkex_resp_y_bp_p384r1[48] = { |
| 1933 | 0x2f, 0xd9, 0x6a, 0xc7, 0x3e, 0xec, 0x76, 0x65, |
| 1934 | 0x2d, 0x38, 0x7f, 0xec, 0x63, 0x26, 0x3f, 0x04, |
| 1935 | 0xd8, 0x4e, 0xff, 0xe1, 0x0a, 0x51, 0x74, 0x70, |
| 1936 | 0xe5, 0x46, 0x63, 0x7f, 0x5c, 0xc0, 0xd1, 0x7c, |
| 1937 | 0xfb, 0x2f, 0xea, 0xe2, 0xd8, 0x0f, 0x84, 0xcb, |
| 1938 | 0xe9, 0x39, 0x5c, 0x64, 0xfe, 0xcb, 0x2f, 0xf1 |
| 1939 | }; |
| 1940 | |
| 1941 | /* Brainpool P-512r1 */ |
| 1942 | static const u8 pkex_init_x_bp_p512r1[64] = { |
| 1943 | 0x4c, 0xe9, 0xb6, 0x1c, 0xe2, 0x00, 0x3c, 0x9c, |
| 1944 | 0xa9, 0xc8, 0x56, 0x52, 0xaf, 0x87, 0x3e, 0x51, |
| 1945 | 0x9c, 0xbb, 0x15, 0x31, 0x1e, 0xc1, 0x05, 0xfc, |
| 1946 | 0x7c, 0x77, 0xd7, 0x37, 0x61, 0x27, 0xd0, 0x95, |
| 1947 | 0x98, 0xee, 0x5d, 0xa4, 0x3d, 0x09, 0xdb, 0x3d, |
| 1948 | 0xfa, 0x89, 0x9e, 0x7f, 0xa6, 0xa6, 0x9c, 0xff, |
| 1949 | 0x83, 0x5c, 0x21, 0x6c, 0x3e, 0xf2, 0xfe, 0xdc, |
| 1950 | 0x63, 0xe4, 0xd1, 0x0e, 0x75, 0x45, 0x69, 0x0f |
| 1951 | }; |
| 1952 | static const u8 pkex_init_y_bp_p512r1[64] = { |
| 1953 | 0x50, 0xb5, 0x9b, 0xfa, 0x45, 0x67, 0x75, 0x94, |
| 1954 | 0x44, 0xe7, 0x68, 0xb0, 0xeb, 0x3e, 0xb3, 0xb8, |
| 1955 | 0xf9, 0x99, 0x05, 0xef, 0xae, 0x6c, 0xbc, 0xe3, |
| 1956 | 0xe1, 0xd2, 0x51, 0x54, 0xdf, 0x59, 0xd4, 0x45, |
| 1957 | 0x41, 0x3a, 0xa8, 0x0b, 0x76, 0x32, 0x44, 0x0e, |
| 1958 | 0x07, 0x60, 0x3a, 0x6e, 0xbe, 0xfe, 0xe0, 0x58, |
| 1959 | 0x52, 0xa0, 0xaa, 0x8b, 0xd8, 0x5b, 0xf2, 0x71, |
| 1960 | 0x11, 0x9a, 0x9e, 0x8f, 0x1a, 0xd1, 0xc9, 0x99 |
| 1961 | }; |
| 1962 | static const u8 pkex_resp_x_bp_p512r1[64] = { |
| 1963 | 0x2a, 0x60, 0x32, 0x27, 0xa1, 0xe6, 0x94, 0x72, |
| 1964 | 0x1c, 0x48, 0xbe, 0xc5, 0x77, 0x14, 0x30, 0x76, |
| 1965 | 0xe4, 0xbf, 0xf7, 0x7b, 0xc5, 0xfd, 0xdf, 0x19, |
| 1966 | 0x1e, 0x0f, 0xdf, 0x1c, 0x40, 0xfa, 0x34, 0x9e, |
| 1967 | 0x1f, 0x42, 0x24, 0xa3, 0x2c, 0xd5, 0xc7, 0xc9, |
| 1968 | 0x7b, 0x47, 0x78, 0x96, 0xf1, 0x37, 0x0e, 0x88, |
| 1969 | 0xcb, 0xa6, 0x52, 0x29, 0xd7, 0xa8, 0x38, 0x29, |
| 1970 | 0x8e, 0x6e, 0x23, 0x47, 0xd4, 0x4b, 0x70, 0x3e |
| 1971 | }; |
| 1972 | static const u8 pkex_resp_y_bp_p512r1[64] = { |
| 1973 | 0x80, 0x1f, 0x43, 0xd2, 0x17, 0x35, 0xec, 0x81, |
| 1974 | 0xd9, 0x4b, 0xdc, 0x81, 0x19, 0xd9, 0x5f, 0x68, |
| 1975 | 0x16, 0x84, 0xfe, 0x63, 0x4b, 0x8d, 0x5d, 0xaa, |
| 1976 | 0x88, 0x4a, 0x47, 0x48, 0xd4, 0xea, 0xab, 0x7d, |
| 1977 | 0x6a, 0xbf, 0xe1, 0x28, 0x99, 0x6a, 0x87, 0x1c, |
| 1978 | 0x30, 0xb4, 0x44, 0x2d, 0x75, 0xac, 0x35, 0x09, |
| 1979 | 0x73, 0x24, 0x3d, 0xb4, 0x43, 0xb1, 0xc1, 0x56, |
| 1980 | 0x56, 0xad, 0x30, 0x87, 0xf4, 0xc3, 0x00, 0xc7 |
| 1981 | }; |
| 1982 | |
| 1983 | |
| 1984 | static EVP_PKEY * dpp_pkex_get_role_elem(const struct dpp_curve_params *curve, |
| 1985 | int init) |
| 1986 | { |
| 1987 | EC_GROUP *group; |
| 1988 | size_t len = curve->prime_len; |
| 1989 | const u8 *x, *y; |
| 1990 | EVP_PKEY *res; |
| 1991 | |
| 1992 | switch (curve->ike_group) { |
| 1993 | case 19: |
| 1994 | x = init ? pkex_init_x_p256 : pkex_resp_x_p256; |
| 1995 | y = init ? pkex_init_y_p256 : pkex_resp_y_p256; |
| 1996 | break; |
| 1997 | case 20: |
| 1998 | x = init ? pkex_init_x_p384 : pkex_resp_x_p384; |
| 1999 | y = init ? pkex_init_y_p384 : pkex_resp_y_p384; |
| 2000 | break; |
| 2001 | case 21: |
| 2002 | x = init ? pkex_init_x_p521 : pkex_resp_x_p521; |
| 2003 | y = init ? pkex_init_y_p521 : pkex_resp_y_p521; |
| 2004 | break; |
| 2005 | case 28: |
| 2006 | x = init ? pkex_init_x_bp_p256r1 : pkex_resp_x_bp_p256r1; |
| 2007 | y = init ? pkex_init_y_bp_p256r1 : pkex_resp_y_bp_p256r1; |
| 2008 | break; |
| 2009 | case 29: |
| 2010 | x = init ? pkex_init_x_bp_p384r1 : pkex_resp_x_bp_p384r1; |
| 2011 | y = init ? pkex_init_y_bp_p384r1 : pkex_resp_y_bp_p384r1; |
| 2012 | break; |
| 2013 | case 30: |
| 2014 | x = init ? pkex_init_x_bp_p512r1 : pkex_resp_x_bp_p512r1; |
| 2015 | y = init ? pkex_init_y_bp_p512r1 : pkex_resp_y_bp_p512r1; |
| 2016 | break; |
| 2017 | default: |
| 2018 | return NULL; |
| 2019 | } |
| 2020 | |
| 2021 | group = EC_GROUP_new_by_curve_name(OBJ_txt2nid(curve->name)); |
| 2022 | if (!group) |
| 2023 | return NULL; |
| 2024 | res = dpp_set_pubkey_point_group(group, x, y, len); |
| 2025 | EC_GROUP_free(group); |
| 2026 | return res; |
| 2027 | } |
| 2028 | |
| 2029 | |
| 2030 | EC_POINT * dpp_pkex_derive_Qi(const struct dpp_curve_params *curve, |
| 2031 | const u8 *mac_init, const char *code, |
| 2032 | const char *identifier, BN_CTX *bnctx, |
| 2033 | EC_GROUP **ret_group) |
| 2034 | { |
| 2035 | u8 hash[DPP_MAX_HASH_LEN]; |
| 2036 | const u8 *addr[3]; |
| 2037 | size_t len[3]; |
| 2038 | unsigned int num_elem = 0; |
| 2039 | EC_POINT *Qi = NULL; |
| 2040 | EVP_PKEY *Pi = NULL; |
| 2041 | const EC_KEY *Pi_ec; |
| 2042 | const EC_POINT *Pi_point; |
| 2043 | BIGNUM *hash_bn = NULL; |
| 2044 | const EC_GROUP *group = NULL; |
| 2045 | EC_GROUP *group2 = NULL; |
| 2046 | |
| 2047 | /* Qi = H(MAC-Initiator | [identifier |] code) * Pi */ |
| 2048 | |
| 2049 | wpa_printf(MSG_DEBUG, "DPP: MAC-Initiator: " MACSTR, MAC2STR(mac_init)); |
| 2050 | addr[num_elem] = mac_init; |
| 2051 | len[num_elem] = ETH_ALEN; |
| 2052 | num_elem++; |
| 2053 | if (identifier) { |
| 2054 | wpa_printf(MSG_DEBUG, "DPP: code identifier: %s", |
| 2055 | identifier); |
| 2056 | addr[num_elem] = (const u8 *) identifier; |
| 2057 | len[num_elem] = os_strlen(identifier); |
| 2058 | num_elem++; |
| 2059 | } |
| 2060 | wpa_hexdump_ascii_key(MSG_DEBUG, "DPP: code", code, os_strlen(code)); |
| 2061 | addr[num_elem] = (const u8 *) code; |
| 2062 | len[num_elem] = os_strlen(code); |
| 2063 | num_elem++; |
| 2064 | if (dpp_hash_vector(curve, num_elem, addr, len, hash) < 0) |
| 2065 | goto fail; |
| 2066 | wpa_hexdump_key(MSG_DEBUG, |
| 2067 | "DPP: H(MAC-Initiator | [identifier |] code)", |
| 2068 | hash, curve->hash_len); |
| 2069 | Pi = dpp_pkex_get_role_elem(curve, 1); |
| 2070 | if (!Pi) |
| 2071 | goto fail; |
| 2072 | dpp_debug_print_key("DPP: Pi", Pi); |
| 2073 | Pi_ec = EVP_PKEY_get0_EC_KEY(Pi); |
| 2074 | if (!Pi_ec) |
| 2075 | goto fail; |
| 2076 | Pi_point = EC_KEY_get0_public_key(Pi_ec); |
| 2077 | |
| 2078 | group = EC_KEY_get0_group(Pi_ec); |
| 2079 | if (!group) |
| 2080 | goto fail; |
| 2081 | group2 = EC_GROUP_dup(group); |
| 2082 | if (!group2) |
| 2083 | goto fail; |
| 2084 | Qi = EC_POINT_new(group2); |
| 2085 | if (!Qi) { |
| 2086 | EC_GROUP_free(group2); |
| 2087 | goto fail; |
| 2088 | } |
| 2089 | hash_bn = BN_bin2bn(hash, curve->hash_len, NULL); |
| 2090 | if (!hash_bn || |
| 2091 | EC_POINT_mul(group2, Qi, NULL, Pi_point, hash_bn, bnctx) != 1) |
| 2092 | goto fail; |
| 2093 | if (EC_POINT_is_at_infinity(group, Qi)) { |
| 2094 | wpa_printf(MSG_INFO, "DPP: Qi is the point-at-infinity"); |
| 2095 | goto fail; |
| 2096 | } |
| 2097 | dpp_debug_print_point("DPP: Qi", group, Qi); |
| 2098 | out: |
| 2099 | EVP_PKEY_free(Pi); |
| 2100 | BN_clear_free(hash_bn); |
| 2101 | if (ret_group && Qi) |
| 2102 | *ret_group = group2; |
| 2103 | else |
| 2104 | EC_GROUP_free(group2); |
| 2105 | return Qi; |
| 2106 | fail: |
| 2107 | EC_POINT_free(Qi); |
| 2108 | Qi = NULL; |
| 2109 | goto out; |
| 2110 | } |
| 2111 | |
| 2112 | |
| 2113 | EC_POINT * dpp_pkex_derive_Qr(const struct dpp_curve_params *curve, |
| 2114 | const u8 *mac_resp, const char *code, |
| 2115 | const char *identifier, BN_CTX *bnctx, |
| 2116 | EC_GROUP **ret_group) |
| 2117 | { |
| 2118 | u8 hash[DPP_MAX_HASH_LEN]; |
| 2119 | const u8 *addr[3]; |
| 2120 | size_t len[3]; |
| 2121 | unsigned int num_elem = 0; |
| 2122 | EC_POINT *Qr = NULL; |
| 2123 | EVP_PKEY *Pr = NULL; |
| 2124 | const EC_KEY *Pr_ec; |
| 2125 | const EC_POINT *Pr_point; |
| 2126 | BIGNUM *hash_bn = NULL; |
| 2127 | const EC_GROUP *group = NULL; |
| 2128 | EC_GROUP *group2 = NULL; |
| 2129 | |
| 2130 | /* Qr = H(MAC-Responder | | [identifier | ] code) * Pr */ |
| 2131 | |
| 2132 | wpa_printf(MSG_DEBUG, "DPP: MAC-Responder: " MACSTR, MAC2STR(mac_resp)); |
| 2133 | addr[num_elem] = mac_resp; |
| 2134 | len[num_elem] = ETH_ALEN; |
| 2135 | num_elem++; |
| 2136 | if (identifier) { |
| 2137 | wpa_printf(MSG_DEBUG, "DPP: code identifier: %s", |
| 2138 | identifier); |
| 2139 | addr[num_elem] = (const u8 *) identifier; |
| 2140 | len[num_elem] = os_strlen(identifier); |
| 2141 | num_elem++; |
| 2142 | } |
| 2143 | wpa_hexdump_ascii_key(MSG_DEBUG, "DPP: code", code, os_strlen(code)); |
| 2144 | addr[num_elem] = (const u8 *) code; |
| 2145 | len[num_elem] = os_strlen(code); |
| 2146 | num_elem++; |
| 2147 | if (dpp_hash_vector(curve, num_elem, addr, len, hash) < 0) |
| 2148 | goto fail; |
| 2149 | wpa_hexdump_key(MSG_DEBUG, |
| 2150 | "DPP: H(MAC-Responder | [identifier |] code)", |
| 2151 | hash, curve->hash_len); |
| 2152 | Pr = dpp_pkex_get_role_elem(curve, 0); |
| 2153 | if (!Pr) |
| 2154 | goto fail; |
| 2155 | dpp_debug_print_key("DPP: Pr", Pr); |
| 2156 | Pr_ec = EVP_PKEY_get0_EC_KEY(Pr); |
| 2157 | if (!Pr_ec) |
| 2158 | goto fail; |
| 2159 | Pr_point = EC_KEY_get0_public_key(Pr_ec); |
| 2160 | |
| 2161 | group = EC_KEY_get0_group(Pr_ec); |
| 2162 | if (!group) |
| 2163 | goto fail; |
| 2164 | group2 = EC_GROUP_dup(group); |
| 2165 | if (!group2) |
| 2166 | goto fail; |
| 2167 | Qr = EC_POINT_new(group2); |
| 2168 | if (!Qr) { |
| 2169 | EC_GROUP_free(group2); |
| 2170 | goto fail; |
| 2171 | } |
| 2172 | hash_bn = BN_bin2bn(hash, curve->hash_len, NULL); |
| 2173 | if (!hash_bn || |
| 2174 | EC_POINT_mul(group2, Qr, NULL, Pr_point, hash_bn, bnctx) != 1) |
| 2175 | goto fail; |
| 2176 | if (EC_POINT_is_at_infinity(group, Qr)) { |
| 2177 | wpa_printf(MSG_INFO, "DPP: Qr is the point-at-infinity"); |
| 2178 | goto fail; |
| 2179 | } |
| 2180 | dpp_debug_print_point("DPP: Qr", group, Qr); |
| 2181 | out: |
| 2182 | EVP_PKEY_free(Pr); |
| 2183 | BN_clear_free(hash_bn); |
| 2184 | if (ret_group && Qr) |
| 2185 | *ret_group = group2; |
| 2186 | else |
| 2187 | EC_GROUP_free(group2); |
| 2188 | return Qr; |
| 2189 | fail: |
| 2190 | EC_POINT_free(Qr); |
| 2191 | Qr = NULL; |
| 2192 | goto out; |
| 2193 | } |
| 2194 | |
| 2195 | |
| 2196 | int dpp_pkex_derive_z(const u8 *mac_init, const u8 *mac_resp, |
| 2197 | const u8 *Mx, size_t Mx_len, |
| 2198 | const u8 *Nx, size_t Nx_len, |
| 2199 | const char *code, |
| 2200 | const u8 *Kx, size_t Kx_len, |
| 2201 | u8 *z, unsigned int hash_len) |
| 2202 | { |
| 2203 | u8 salt[DPP_MAX_HASH_LEN], prk[DPP_MAX_HASH_LEN]; |
| 2204 | int res; |
| 2205 | u8 *info, *pos; |
| 2206 | size_t info_len; |
| 2207 | |
| 2208 | /* z = HKDF(<>, MAC-Initiator | MAC-Responder | M.x | N.x | code, K.x) |
| 2209 | */ |
| 2210 | |
| 2211 | /* HKDF-Extract(<>, IKM=K.x) */ |
| 2212 | os_memset(salt, 0, hash_len); |
| 2213 | if (dpp_hmac(hash_len, salt, hash_len, Kx, Kx_len, prk) < 0) |
| 2214 | return -1; |
| 2215 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK = HKDF-Extract(<>, IKM)", |
| 2216 | prk, hash_len); |
| 2217 | info_len = 2 * ETH_ALEN + Mx_len + Nx_len + os_strlen(code); |
| 2218 | info = os_malloc(info_len); |
| 2219 | if (!info) |
| 2220 | return -1; |
| 2221 | pos = info; |
| 2222 | os_memcpy(pos, mac_init, ETH_ALEN); |
| 2223 | pos += ETH_ALEN; |
| 2224 | os_memcpy(pos, mac_resp, ETH_ALEN); |
| 2225 | pos += ETH_ALEN; |
| 2226 | os_memcpy(pos, Mx, Mx_len); |
| 2227 | pos += Mx_len; |
| 2228 | os_memcpy(pos, Nx, Nx_len); |
| 2229 | pos += Nx_len; |
| 2230 | os_memcpy(pos, code, os_strlen(code)); |
| 2231 | |
| 2232 | /* HKDF-Expand(PRK, info, L) */ |
| 2233 | if (hash_len == 32) |
| 2234 | res = hmac_sha256_kdf(prk, hash_len, NULL, info, info_len, |
| 2235 | z, hash_len); |
| 2236 | else if (hash_len == 48) |
| 2237 | res = hmac_sha384_kdf(prk, hash_len, NULL, info, info_len, |
| 2238 | z, hash_len); |
| 2239 | else if (hash_len == 64) |
| 2240 | res = hmac_sha512_kdf(prk, hash_len, NULL, info, info_len, |
| 2241 | z, hash_len); |
| 2242 | else |
| 2243 | res = -1; |
| 2244 | os_free(info); |
| 2245 | os_memset(prk, 0, hash_len); |
| 2246 | if (res < 0) |
| 2247 | return -1; |
| 2248 | |
| 2249 | wpa_hexdump_key(MSG_DEBUG, "DPP: z = HKDF-Expand(PRK, info, L)", |
| 2250 | z, hash_len); |
| 2251 | return 0; |
| 2252 | } |
| 2253 | |
| 2254 | |
| 2255 | int dpp_reconfig_derive_ke_responder(struct dpp_authentication *auth, |
| 2256 | const u8 *net_access_key, |
| 2257 | size_t net_access_key_len, |
| 2258 | struct json_token *peer_net_access_key) |
| 2259 | { |
| 2260 | BN_CTX *bnctx = NULL; |
| 2261 | EVP_PKEY *own_key = NULL, *peer_key = NULL; |
| 2262 | BIGNUM *sum = NULL, *q = NULL, *mx = NULL; |
| 2263 | EC_POINT *m = NULL; |
| 2264 | const EC_KEY *cR, *pR; |
| 2265 | const EC_GROUP *group; |
| 2266 | const BIGNUM *cR_bn, *pR_bn; |
| 2267 | const EC_POINT *CI_point; |
| 2268 | const EC_KEY *CI; |
| 2269 | u8 Mx[DPP_MAX_SHARED_SECRET_LEN]; |
| 2270 | u8 prk[DPP_MAX_HASH_LEN]; |
| 2271 | const struct dpp_curve_params *curve; |
| 2272 | int res = -1; |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2273 | u8 nonces[2 * DPP_MAX_NONCE_LEN]; |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2274 | |
| 2275 | own_key = dpp_set_keypair(&auth->curve, net_access_key, |
| 2276 | net_access_key_len); |
| 2277 | if (!own_key) { |
| 2278 | dpp_auth_fail(auth, "Failed to parse own netAccessKey"); |
| 2279 | goto fail; |
| 2280 | } |
| 2281 | |
| 2282 | peer_key = dpp_parse_jwk(peer_net_access_key, &curve); |
| 2283 | if (!peer_key) |
| 2284 | goto fail; |
| 2285 | dpp_debug_print_key("DPP: Received netAccessKey", peer_key); |
| 2286 | |
| 2287 | if (auth->curve != curve) { |
| 2288 | wpa_printf(MSG_DEBUG, |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2289 | "DPP: Mismatching netAccessKey curves (own=%s != peer=%s)", |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2290 | auth->curve->name, curve->name); |
| 2291 | goto fail; |
| 2292 | } |
| 2293 | |
| 2294 | auth->own_protocol_key = dpp_gen_keypair(curve); |
| 2295 | if (!auth->own_protocol_key) |
| 2296 | goto fail; |
| 2297 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2298 | if (random_get_bytes(auth->e_nonce, auth->curve->nonce_len)) { |
| 2299 | wpa_printf(MSG_ERROR, "DPP: Failed to generate E-nonce"); |
| 2300 | goto fail; |
| 2301 | } |
| 2302 | wpa_hexdump_key(MSG_DEBUG, "DPP: E-nonce", |
| 2303 | auth->e_nonce, auth->curve->nonce_len); |
| 2304 | |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2305 | /* M = { cR + pR } * CI */ |
| 2306 | cR = EVP_PKEY_get0_EC_KEY(own_key); |
| 2307 | pR = EVP_PKEY_get0_EC_KEY(auth->own_protocol_key); |
Hai Shalom | 6084025 | 2021-02-19 19:02:11 -0800 | [diff] [blame^] | 2308 | if (!pR) |
| 2309 | goto fail; |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2310 | group = EC_KEY_get0_group(pR); |
| 2311 | bnctx = BN_CTX_new(); |
| 2312 | sum = BN_new(); |
| 2313 | mx = BN_new(); |
| 2314 | q = BN_new(); |
| 2315 | m = EC_POINT_new(group); |
Hai Shalom | 6084025 | 2021-02-19 19:02:11 -0800 | [diff] [blame^] | 2316 | if (!cR || !bnctx || !sum || !mx || !q || !m) |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2317 | goto fail; |
| 2318 | cR_bn = EC_KEY_get0_private_key(cR); |
| 2319 | pR_bn = EC_KEY_get0_private_key(pR); |
| 2320 | if (!cR_bn || !pR_bn) |
| 2321 | goto fail; |
| 2322 | CI = EVP_PKEY_get0_EC_KEY(peer_key); |
| 2323 | CI_point = EC_KEY_get0_public_key(CI); |
| 2324 | if (EC_GROUP_get_order(group, q, bnctx) != 1 || |
| 2325 | BN_mod_add(sum, cR_bn, pR_bn, q, bnctx) != 1 || |
| 2326 | EC_POINT_mul(group, m, NULL, CI_point, sum, bnctx) != 1 || |
| 2327 | EC_POINT_get_affine_coordinates_GFp(group, m, mx, NULL, |
| 2328 | bnctx) != 1) { |
| 2329 | wpa_printf(MSG_ERROR, |
| 2330 | "OpenSSL: failed: %s", |
| 2331 | ERR_error_string(ERR_get_error(), NULL)); |
| 2332 | goto fail; |
| 2333 | } |
| 2334 | |
| 2335 | if (dpp_bn2bin_pad(mx, Mx, curve->prime_len) < 0) |
| 2336 | goto fail; |
| 2337 | wpa_hexdump_key(MSG_DEBUG, "DPP: M.x", Mx, curve->prime_len); |
| 2338 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2339 | /* ke = HKDF(C-nonce | E-nonce, "dpp reconfig key", M.x) */ |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2340 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2341 | /* HKDF-Extract(C-nonce | E-nonce, M.x) */ |
| 2342 | os_memcpy(nonces, auth->c_nonce, curve->nonce_len); |
| 2343 | os_memcpy(&nonces[curve->nonce_len], auth->e_nonce, curve->nonce_len); |
| 2344 | if (dpp_hmac(curve->hash_len, nonces, 2 * curve->nonce_len, |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2345 | Mx, curve->prime_len, prk) < 0) |
| 2346 | goto fail; |
| 2347 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK", prk, curve->hash_len); |
| 2348 | |
| 2349 | /* HKDF-Expand(PRK, "dpp reconfig key", L) */ |
| 2350 | if (dpp_hkdf_expand(curve->hash_len, prk, curve->hash_len, |
| 2351 | "dpp reconfig key", auth->ke, curve->hash_len) < 0) |
| 2352 | goto fail; |
| 2353 | wpa_hexdump_key(MSG_DEBUG, |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2354 | "DPP: ke = HKDF(C-nonce | E-nonce, \"dpp reconfig key\", M.x)", |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2355 | auth->ke, curve->hash_len); |
| 2356 | |
| 2357 | res = 0; |
| 2358 | EVP_PKEY_free(auth->reconfig_old_protocol_key); |
| 2359 | auth->reconfig_old_protocol_key = own_key; |
| 2360 | own_key = NULL; |
| 2361 | fail: |
| 2362 | forced_memzero(prk, sizeof(prk)); |
| 2363 | forced_memzero(Mx, sizeof(Mx)); |
| 2364 | EC_POINT_clear_free(m); |
| 2365 | BN_free(q); |
| 2366 | BN_clear_free(mx); |
| 2367 | BN_clear_free(sum); |
| 2368 | EVP_PKEY_free(own_key); |
| 2369 | EVP_PKEY_free(peer_key); |
| 2370 | BN_CTX_free(bnctx); |
| 2371 | return res; |
| 2372 | } |
| 2373 | |
| 2374 | |
| 2375 | int dpp_reconfig_derive_ke_initiator(struct dpp_authentication *auth, |
| 2376 | const u8 *r_proto, u16 r_proto_len, |
| 2377 | struct json_token *net_access_key) |
| 2378 | { |
| 2379 | BN_CTX *bnctx = NULL; |
| 2380 | EVP_PKEY *pr = NULL, *peer_key = NULL; |
| 2381 | EC_POINT *sum = NULL, *m = NULL; |
| 2382 | BIGNUM *mx = NULL; |
| 2383 | const EC_KEY *cI, *CR, *PR; |
| 2384 | const EC_GROUP *group; |
| 2385 | const EC_POINT *CR_point, *PR_point; |
| 2386 | const BIGNUM *cI_bn; |
| 2387 | u8 Mx[DPP_MAX_SHARED_SECRET_LEN]; |
| 2388 | u8 prk[DPP_MAX_HASH_LEN]; |
| 2389 | int res = -1; |
| 2390 | const struct dpp_curve_params *curve; |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2391 | u8 nonces[2 * DPP_MAX_NONCE_LEN]; |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2392 | |
| 2393 | pr = dpp_set_pubkey_point(auth->conf->connector_key, |
| 2394 | r_proto, r_proto_len); |
| 2395 | if (!pr) { |
| 2396 | dpp_auth_fail(auth, "Invalid Responder Protocol Key"); |
| 2397 | goto fail; |
| 2398 | } |
| 2399 | dpp_debug_print_key("Peer (Responder) Protocol Key", pr); |
| 2400 | EVP_PKEY_free(auth->peer_protocol_key); |
| 2401 | auth->peer_protocol_key = pr; |
| 2402 | pr = NULL; |
| 2403 | |
| 2404 | peer_key = dpp_parse_jwk(net_access_key, &curve); |
| 2405 | if (!peer_key) |
| 2406 | goto fail; |
| 2407 | dpp_debug_print_key("DPP: Received netAccessKey", peer_key); |
| 2408 | if (auth->curve != curve) { |
| 2409 | wpa_printf(MSG_DEBUG, |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2410 | "DPP: Mismatching netAccessKey curves (own=%s != peer=%s)", |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2411 | auth->curve->name, curve->name); |
| 2412 | goto fail; |
| 2413 | } |
| 2414 | |
| 2415 | /* M = cI * { CR + PR } */ |
| 2416 | cI = EVP_PKEY_get0_EC_KEY(auth->conf->connector_key); |
| 2417 | cI_bn = EC_KEY_get0_private_key(cI); |
| 2418 | group = EC_KEY_get0_group(cI); |
| 2419 | bnctx = BN_CTX_new(); |
| 2420 | sum = EC_POINT_new(group); |
| 2421 | m = EC_POINT_new(group); |
| 2422 | mx = BN_new(); |
| 2423 | CR = EVP_PKEY_get0_EC_KEY(peer_key); |
| 2424 | PR = EVP_PKEY_get0_EC_KEY(auth->peer_protocol_key); |
| 2425 | CR_point = EC_KEY_get0_public_key(CR); |
| 2426 | PR_point = EC_KEY_get0_public_key(PR); |
| 2427 | if (!bnctx || !sum || !m || !mx || |
| 2428 | EC_POINT_add(group, sum, CR_point, PR_point, bnctx) != 1 || |
| 2429 | EC_POINT_mul(group, m, NULL, sum, cI_bn, bnctx) != 1 || |
| 2430 | EC_POINT_get_affine_coordinates_GFp(group, m, mx, NULL, |
| 2431 | bnctx) != 1 || |
| 2432 | dpp_bn2bin_pad(mx, Mx, curve->prime_len) < 0) |
| 2433 | goto fail; |
| 2434 | |
| 2435 | wpa_hexdump_key(MSG_DEBUG, "DPP: M.x", Mx, curve->prime_len); |
| 2436 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2437 | /* ke = HKDF(C-nonce | E-nonce, "dpp reconfig key", M.x) */ |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2438 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2439 | /* HKDF-Extract(C-nonce | E-nonce, M.x) */ |
| 2440 | os_memcpy(nonces, auth->c_nonce, curve->nonce_len); |
| 2441 | os_memcpy(&nonces[curve->nonce_len], auth->e_nonce, curve->nonce_len); |
| 2442 | if (dpp_hmac(curve->hash_len, nonces, 2 * curve->nonce_len, |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2443 | Mx, curve->prime_len, prk) < 0) |
| 2444 | goto fail; |
| 2445 | wpa_hexdump_key(MSG_DEBUG, "DPP: PRK", prk, curve->hash_len); |
| 2446 | |
| 2447 | /* HKDF-Expand(PRK, "dpp reconfig key", L) */ |
| 2448 | if (dpp_hkdf_expand(curve->hash_len, prk, curve->hash_len, |
| 2449 | "dpp reconfig key", auth->ke, curve->hash_len) < 0) |
| 2450 | goto fail; |
| 2451 | wpa_hexdump_key(MSG_DEBUG, |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2452 | "DPP: ke = HKDF(C-nonce | E-nonce, \"dpp reconfig key\", M.x)", |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 2453 | auth->ke, curve->hash_len); |
| 2454 | |
| 2455 | res = 0; |
| 2456 | fail: |
| 2457 | forced_memzero(prk, sizeof(prk)); |
| 2458 | forced_memzero(Mx, sizeof(Mx)); |
| 2459 | EVP_PKEY_free(pr); |
| 2460 | EVP_PKEY_free(peer_key); |
| 2461 | EC_POINT_clear_free(sum); |
| 2462 | EC_POINT_clear_free(m); |
| 2463 | BN_clear_free(mx); |
| 2464 | BN_CTX_free(bnctx); |
| 2465 | return res; |
| 2466 | } |
| 2467 | |
| 2468 | |
| 2469 | static char * |
| 2470 | dpp_build_jws_prot_hdr(struct dpp_configurator *conf, size_t *signed1_len) |
| 2471 | { |
| 2472 | struct wpabuf *jws_prot_hdr; |
| 2473 | char *signed1; |
| 2474 | |
| 2475 | jws_prot_hdr = wpabuf_alloc(100); |
| 2476 | if (!jws_prot_hdr) |
| 2477 | return NULL; |
| 2478 | json_start_object(jws_prot_hdr, NULL); |
| 2479 | json_add_string(jws_prot_hdr, "typ", "dppCon"); |
| 2480 | json_value_sep(jws_prot_hdr); |
| 2481 | json_add_string(jws_prot_hdr, "kid", conf->kid); |
| 2482 | json_value_sep(jws_prot_hdr); |
| 2483 | json_add_string(jws_prot_hdr, "alg", conf->curve->jws_alg); |
| 2484 | json_end_object(jws_prot_hdr); |
| 2485 | signed1 = base64_url_encode(wpabuf_head(jws_prot_hdr), |
| 2486 | wpabuf_len(jws_prot_hdr), |
| 2487 | signed1_len); |
| 2488 | wpabuf_free(jws_prot_hdr); |
| 2489 | return signed1; |
| 2490 | } |
| 2491 | |
| 2492 | |
| 2493 | static char * |
| 2494 | dpp_build_conn_signature(struct dpp_configurator *conf, |
| 2495 | const char *signed1, size_t signed1_len, |
| 2496 | const char *signed2, size_t signed2_len, |
| 2497 | size_t *signed3_len) |
| 2498 | { |
| 2499 | const struct dpp_curve_params *curve; |
| 2500 | char *signed3 = NULL; |
| 2501 | unsigned char *signature = NULL; |
| 2502 | const unsigned char *p; |
| 2503 | size_t signature_len; |
| 2504 | EVP_MD_CTX *md_ctx = NULL; |
| 2505 | ECDSA_SIG *sig = NULL; |
| 2506 | char *dot = "."; |
| 2507 | const EVP_MD *sign_md; |
| 2508 | const BIGNUM *r, *s; |
| 2509 | |
| 2510 | curve = conf->curve; |
| 2511 | if (curve->hash_len == SHA256_MAC_LEN) { |
| 2512 | sign_md = EVP_sha256(); |
| 2513 | } else if (curve->hash_len == SHA384_MAC_LEN) { |
| 2514 | sign_md = EVP_sha384(); |
| 2515 | } else if (curve->hash_len == SHA512_MAC_LEN) { |
| 2516 | sign_md = EVP_sha512(); |
| 2517 | } else { |
| 2518 | wpa_printf(MSG_DEBUG, "DPP: Unknown signature algorithm"); |
| 2519 | goto fail; |
| 2520 | } |
| 2521 | |
| 2522 | md_ctx = EVP_MD_CTX_create(); |
| 2523 | if (!md_ctx) |
| 2524 | goto fail; |
| 2525 | |
| 2526 | ERR_clear_error(); |
| 2527 | if (EVP_DigestSignInit(md_ctx, NULL, sign_md, NULL, conf->csign) != 1) { |
| 2528 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestSignInit failed: %s", |
| 2529 | ERR_error_string(ERR_get_error(), NULL)); |
| 2530 | goto fail; |
| 2531 | } |
| 2532 | if (EVP_DigestSignUpdate(md_ctx, signed1, signed1_len) != 1 || |
| 2533 | EVP_DigestSignUpdate(md_ctx, dot, 1) != 1 || |
| 2534 | EVP_DigestSignUpdate(md_ctx, signed2, signed2_len) != 1) { |
| 2535 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestSignUpdate failed: %s", |
| 2536 | ERR_error_string(ERR_get_error(), NULL)); |
| 2537 | goto fail; |
| 2538 | } |
| 2539 | if (EVP_DigestSignFinal(md_ctx, NULL, &signature_len) != 1) { |
| 2540 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestSignFinal failed: %s", |
| 2541 | ERR_error_string(ERR_get_error(), NULL)); |
| 2542 | goto fail; |
| 2543 | } |
| 2544 | signature = os_malloc(signature_len); |
| 2545 | if (!signature) |
| 2546 | goto fail; |
| 2547 | if (EVP_DigestSignFinal(md_ctx, signature, &signature_len) != 1) { |
| 2548 | wpa_printf(MSG_DEBUG, "DPP: EVP_DigestSignFinal failed: %s", |
| 2549 | ERR_error_string(ERR_get_error(), NULL)); |
| 2550 | goto fail; |
| 2551 | } |
| 2552 | wpa_hexdump(MSG_DEBUG, "DPP: signedConnector ECDSA signature (DER)", |
| 2553 | signature, signature_len); |
| 2554 | /* Convert to raw coordinates r,s */ |
| 2555 | p = signature; |
| 2556 | sig = d2i_ECDSA_SIG(NULL, &p, signature_len); |
| 2557 | if (!sig) |
| 2558 | goto fail; |
| 2559 | ECDSA_SIG_get0(sig, &r, &s); |
| 2560 | if (dpp_bn2bin_pad(r, signature, curve->prime_len) < 0 || |
| 2561 | dpp_bn2bin_pad(s, signature + curve->prime_len, |
| 2562 | curve->prime_len) < 0) |
| 2563 | goto fail; |
| 2564 | signature_len = 2 * curve->prime_len; |
| 2565 | wpa_hexdump(MSG_DEBUG, "DPP: signedConnector ECDSA signature (raw r,s)", |
| 2566 | signature, signature_len); |
| 2567 | signed3 = base64_url_encode(signature, signature_len, signed3_len); |
| 2568 | fail: |
| 2569 | EVP_MD_CTX_destroy(md_ctx); |
| 2570 | ECDSA_SIG_free(sig); |
| 2571 | os_free(signature); |
| 2572 | return signed3; |
| 2573 | } |
| 2574 | |
| 2575 | char * dpp_sign_connector(struct dpp_configurator *conf, |
| 2576 | const struct wpabuf *dppcon) |
| 2577 | { |
| 2578 | char *signed1 = NULL, *signed2 = NULL, *signed3 = NULL; |
| 2579 | char *signed_conn = NULL, *pos; |
| 2580 | size_t signed1_len, signed2_len, signed3_len; |
| 2581 | |
| 2582 | signed1 = dpp_build_jws_prot_hdr(conf, &signed1_len); |
| 2583 | signed2 = base64_url_encode(wpabuf_head(dppcon), wpabuf_len(dppcon), |
| 2584 | &signed2_len); |
| 2585 | if (!signed1 || !signed2) |
| 2586 | goto fail; |
| 2587 | |
| 2588 | signed3 = dpp_build_conn_signature(conf, signed1, signed1_len, |
| 2589 | signed2, signed2_len, &signed3_len); |
| 2590 | if (!signed3) |
| 2591 | goto fail; |
| 2592 | |
| 2593 | signed_conn = os_malloc(signed1_len + signed2_len + signed3_len + 3); |
| 2594 | if (!signed_conn) |
| 2595 | goto fail; |
| 2596 | pos = signed_conn; |
| 2597 | os_memcpy(pos, signed1, signed1_len); |
| 2598 | pos += signed1_len; |
| 2599 | *pos++ = '.'; |
| 2600 | os_memcpy(pos, signed2, signed2_len); |
| 2601 | pos += signed2_len; |
| 2602 | *pos++ = '.'; |
| 2603 | os_memcpy(pos, signed3, signed3_len); |
| 2604 | pos += signed3_len; |
| 2605 | *pos = '\0'; |
| 2606 | |
| 2607 | fail: |
| 2608 | os_free(signed1); |
| 2609 | os_free(signed2); |
| 2610 | os_free(signed3); |
| 2611 | return signed_conn; |
| 2612 | } |
| 2613 | |
| 2614 | |
| 2615 | #ifdef CONFIG_DPP2 |
| 2616 | |
| 2617 | struct dpp_pfs * dpp_pfs_init(const u8 *net_access_key, |
| 2618 | size_t net_access_key_len) |
| 2619 | { |
| 2620 | struct wpabuf *pub = NULL; |
| 2621 | EVP_PKEY *own_key; |
| 2622 | struct dpp_pfs *pfs; |
| 2623 | |
| 2624 | pfs = os_zalloc(sizeof(*pfs)); |
| 2625 | if (!pfs) |
| 2626 | return NULL; |
| 2627 | |
| 2628 | own_key = dpp_set_keypair(&pfs->curve, net_access_key, |
| 2629 | net_access_key_len); |
| 2630 | if (!own_key) { |
| 2631 | wpa_printf(MSG_ERROR, "DPP: Failed to parse own netAccessKey"); |
| 2632 | goto fail; |
| 2633 | } |
| 2634 | EVP_PKEY_free(own_key); |
| 2635 | |
| 2636 | pfs->ecdh = crypto_ecdh_init(pfs->curve->ike_group); |
| 2637 | if (!pfs->ecdh) |
| 2638 | goto fail; |
| 2639 | |
| 2640 | pub = crypto_ecdh_get_pubkey(pfs->ecdh, 0); |
| 2641 | pub = wpabuf_zeropad(pub, pfs->curve->prime_len); |
| 2642 | if (!pub) |
| 2643 | goto fail; |
| 2644 | |
| 2645 | pfs->ie = wpabuf_alloc(5 + wpabuf_len(pub)); |
| 2646 | if (!pfs->ie) |
| 2647 | goto fail; |
| 2648 | wpabuf_put_u8(pfs->ie, WLAN_EID_EXTENSION); |
| 2649 | wpabuf_put_u8(pfs->ie, 1 + 2 + wpabuf_len(pub)); |
| 2650 | wpabuf_put_u8(pfs->ie, WLAN_EID_EXT_OWE_DH_PARAM); |
| 2651 | wpabuf_put_le16(pfs->ie, pfs->curve->ike_group); |
| 2652 | wpabuf_put_buf(pfs->ie, pub); |
| 2653 | wpabuf_free(pub); |
| 2654 | wpa_hexdump_buf(MSG_DEBUG, "DPP: Diffie-Hellman Parameter element", |
| 2655 | pfs->ie); |
| 2656 | |
| 2657 | return pfs; |
| 2658 | fail: |
| 2659 | wpabuf_free(pub); |
| 2660 | dpp_pfs_free(pfs); |
| 2661 | return NULL; |
| 2662 | } |
| 2663 | |
| 2664 | |
| 2665 | int dpp_pfs_process(struct dpp_pfs *pfs, const u8 *peer_ie, size_t peer_ie_len) |
| 2666 | { |
| 2667 | if (peer_ie_len < 2) |
| 2668 | return -1; |
| 2669 | if (WPA_GET_LE16(peer_ie) != pfs->curve->ike_group) { |
| 2670 | wpa_printf(MSG_DEBUG, "DPP: Peer used different group for PFS"); |
| 2671 | return -1; |
| 2672 | } |
| 2673 | |
| 2674 | pfs->secret = crypto_ecdh_set_peerkey(pfs->ecdh, 0, peer_ie + 2, |
| 2675 | peer_ie_len - 2); |
| 2676 | pfs->secret = wpabuf_zeropad(pfs->secret, pfs->curve->prime_len); |
| 2677 | if (!pfs->secret) { |
| 2678 | wpa_printf(MSG_DEBUG, "DPP: Invalid peer DH public key"); |
| 2679 | return -1; |
| 2680 | } |
| 2681 | wpa_hexdump_buf_key(MSG_DEBUG, "DPP: DH shared secret", pfs->secret); |
| 2682 | return 0; |
| 2683 | } |
| 2684 | |
| 2685 | |
| 2686 | void dpp_pfs_free(struct dpp_pfs *pfs) |
| 2687 | { |
| 2688 | if (!pfs) |
| 2689 | return; |
| 2690 | crypto_ecdh_deinit(pfs->ecdh); |
| 2691 | wpabuf_free(pfs->ie); |
| 2692 | wpabuf_clear_free(pfs->secret); |
| 2693 | os_free(pfs); |
| 2694 | } |
| 2695 | |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2696 | |
| 2697 | struct wpabuf * dpp_build_csr(struct dpp_authentication *auth, const char *name) |
| 2698 | { |
| 2699 | X509_REQ *req = NULL; |
| 2700 | struct wpabuf *buf = NULL; |
| 2701 | unsigned char *der; |
| 2702 | int der_len; |
| 2703 | EVP_PKEY *key; |
| 2704 | const EVP_MD *sign_md; |
| 2705 | unsigned int hash_len = auth->curve->hash_len; |
| 2706 | EC_KEY *eckey; |
| 2707 | BIO *out = NULL; |
| 2708 | u8 cp[DPP_CP_LEN]; |
| 2709 | char *password; |
| 2710 | size_t password_len; |
| 2711 | int res; |
| 2712 | |
| 2713 | /* TODO: use auth->csrattrs */ |
| 2714 | |
| 2715 | /* TODO: support generation of a new private key if csrAttrs requests |
| 2716 | * a specific group to be used */ |
| 2717 | key = auth->own_protocol_key; |
| 2718 | |
| 2719 | eckey = EVP_PKEY_get1_EC_KEY(key); |
| 2720 | if (!eckey) |
| 2721 | goto fail; |
| 2722 | der = NULL; |
| 2723 | der_len = i2d_ECPrivateKey(eckey, &der); |
| 2724 | if (der_len <= 0) |
| 2725 | goto fail; |
| 2726 | wpabuf_free(auth->priv_key); |
| 2727 | auth->priv_key = wpabuf_alloc_copy(der, der_len); |
| 2728 | OPENSSL_free(der); |
| 2729 | if (!auth->priv_key) |
| 2730 | goto fail; |
| 2731 | |
| 2732 | req = X509_REQ_new(); |
| 2733 | if (!req || !X509_REQ_set_pubkey(req, key)) |
| 2734 | goto fail; |
| 2735 | |
| 2736 | if (name) { |
| 2737 | X509_NAME *n; |
| 2738 | |
| 2739 | n = X509_REQ_get_subject_name(req); |
| 2740 | if (!n) |
| 2741 | goto fail; |
| 2742 | |
| 2743 | if (X509_NAME_add_entry_by_txt( |
| 2744 | n, "CN", MBSTRING_UTF8, |
| 2745 | (const unsigned char *) name, -1, -1, 0) != 1) |
| 2746 | goto fail; |
| 2747 | } |
| 2748 | |
| 2749 | /* cp = HKDF-Expand(bk, "CSR challengePassword", 64) */ |
| 2750 | if (dpp_hkdf_expand(hash_len, auth->bk, hash_len, |
| 2751 | "CSR challengePassword", cp, DPP_CP_LEN) < 0) |
| 2752 | goto fail; |
| 2753 | wpa_hexdump_key(MSG_DEBUG, |
| 2754 | "DPP: cp = HKDF-Expand(bk, \"CSR challengePassword\", 64)", |
| 2755 | cp, DPP_CP_LEN); |
| 2756 | password = base64_encode_no_lf(cp, DPP_CP_LEN, &password_len); |
| 2757 | forced_memzero(cp, DPP_CP_LEN); |
| 2758 | if (!password) |
| 2759 | goto fail; |
| 2760 | |
| 2761 | res = X509_REQ_add1_attr_by_NID(req, NID_pkcs9_challengePassword, |
| 2762 | V_ASN1_UTF8STRING, |
| 2763 | (const unsigned char *) password, |
| 2764 | password_len); |
| 2765 | bin_clear_free(password, password_len); |
| 2766 | if (!res) |
| 2767 | goto fail; |
| 2768 | |
| 2769 | /* TODO */ |
| 2770 | |
| 2771 | /* TODO: hash func selection based on csrAttrs */ |
| 2772 | if (hash_len == SHA256_MAC_LEN) { |
| 2773 | sign_md = EVP_sha256(); |
| 2774 | } else if (hash_len == SHA384_MAC_LEN) { |
| 2775 | sign_md = EVP_sha384(); |
| 2776 | } else if (hash_len == SHA512_MAC_LEN) { |
| 2777 | sign_md = EVP_sha512(); |
| 2778 | } else { |
| 2779 | wpa_printf(MSG_DEBUG, "DPP: Unknown signature algorithm"); |
| 2780 | goto fail; |
| 2781 | } |
| 2782 | |
| 2783 | if (!X509_REQ_sign(req, key, sign_md)) |
| 2784 | goto fail; |
| 2785 | |
| 2786 | der = NULL; |
| 2787 | der_len = i2d_X509_REQ(req, &der); |
| 2788 | if (der_len < 0) |
| 2789 | goto fail; |
| 2790 | buf = wpabuf_alloc_copy(der, der_len); |
| 2791 | OPENSSL_free(der); |
| 2792 | |
| 2793 | wpa_hexdump_buf(MSG_DEBUG, "DPP: CSR", buf); |
| 2794 | |
| 2795 | fail: |
| 2796 | BIO_free_all(out); |
| 2797 | X509_REQ_free(req); |
| 2798 | return buf; |
| 2799 | } |
| 2800 | |
| 2801 | |
| 2802 | struct wpabuf * dpp_pkcs7_certs(const struct wpabuf *pkcs7) |
| 2803 | { |
| 2804 | #ifdef OPENSSL_IS_BORINGSSL |
| 2805 | CBS pkcs7_cbs; |
| 2806 | #else /* OPENSSL_IS_BORINGSSL */ |
| 2807 | PKCS7 *p7 = NULL; |
| 2808 | const unsigned char *p = wpabuf_head(pkcs7); |
| 2809 | #endif /* OPENSSL_IS_BORINGSSL */ |
| 2810 | STACK_OF(X509) *certs; |
| 2811 | int i, num; |
| 2812 | BIO *out = NULL; |
| 2813 | size_t rlen; |
| 2814 | struct wpabuf *pem = NULL; |
| 2815 | int res; |
| 2816 | |
| 2817 | #ifdef OPENSSL_IS_BORINGSSL |
| 2818 | certs = sk_X509_new_null(); |
| 2819 | if (!certs) |
| 2820 | goto fail; |
| 2821 | CBS_init(&pkcs7_cbs, wpabuf_head(pkcs7), wpabuf_len(pkcs7)); |
| 2822 | if (!PKCS7_get_certificates(certs, &pkcs7_cbs)) { |
| 2823 | wpa_printf(MSG_INFO, "DPP: Could not parse PKCS#7 object: %s", |
| 2824 | ERR_error_string(ERR_get_error(), NULL)); |
| 2825 | goto fail; |
| 2826 | } |
| 2827 | #else /* OPENSSL_IS_BORINGSSL */ |
| 2828 | p7 = d2i_PKCS7(NULL, &p, wpabuf_len(pkcs7)); |
| 2829 | if (!p7) { |
| 2830 | wpa_printf(MSG_INFO, "DPP: Could not parse PKCS#7 object: %s", |
| 2831 | ERR_error_string(ERR_get_error(), NULL)); |
| 2832 | goto fail; |
| 2833 | } |
| 2834 | |
| 2835 | switch (OBJ_obj2nid(p7->type)) { |
| 2836 | case NID_pkcs7_signed: |
| 2837 | certs = p7->d.sign->cert; |
| 2838 | break; |
| 2839 | case NID_pkcs7_signedAndEnveloped: |
| 2840 | certs = p7->d.signed_and_enveloped->cert; |
| 2841 | break; |
| 2842 | default: |
| 2843 | certs = NULL; |
| 2844 | break; |
| 2845 | } |
| 2846 | #endif /* OPENSSL_IS_BORINGSSL */ |
| 2847 | |
| 2848 | if (!certs || ((num = sk_X509_num(certs)) == 0)) { |
| 2849 | wpa_printf(MSG_INFO, |
| 2850 | "DPP: No certificates found in PKCS#7 object"); |
| 2851 | goto fail; |
| 2852 | } |
| 2853 | |
| 2854 | out = BIO_new(BIO_s_mem()); |
| 2855 | if (!out) |
| 2856 | goto fail; |
| 2857 | |
| 2858 | for (i = 0; i < num; i++) { |
| 2859 | X509 *cert = sk_X509_value(certs, i); |
| 2860 | |
| 2861 | PEM_write_bio_X509(out, cert); |
| 2862 | } |
| 2863 | |
| 2864 | rlen = BIO_ctrl_pending(out); |
| 2865 | pem = wpabuf_alloc(rlen); |
| 2866 | if (!pem) |
| 2867 | goto fail; |
| 2868 | res = BIO_read(out, wpabuf_put(pem, 0), rlen); |
| 2869 | if (res <= 0) { |
| 2870 | wpabuf_free(pem); |
Hai Shalom | 6084025 | 2021-02-19 19:02:11 -0800 | [diff] [blame^] | 2871 | pem = NULL; |
Hai Shalom | 899fcc7 | 2020-10-19 14:38:18 -0700 | [diff] [blame] | 2872 | goto fail; |
| 2873 | } |
| 2874 | wpabuf_put(pem, res); |
| 2875 | |
| 2876 | fail: |
| 2877 | #ifdef OPENSSL_IS_BORINGSSL |
| 2878 | if (certs) |
| 2879 | sk_X509_pop_free(certs, X509_free); |
| 2880 | #else /* OPENSSL_IS_BORINGSSL */ |
| 2881 | PKCS7_free(p7); |
| 2882 | #endif /* OPENSSL_IS_BORINGSSL */ |
| 2883 | if (out) |
| 2884 | BIO_free_all(out); |
| 2885 | |
| 2886 | return pem; |
| 2887 | } |
| 2888 | |
| 2889 | |
| 2890 | int dpp_validate_csr(struct dpp_authentication *auth, const struct wpabuf *csr) |
| 2891 | { |
| 2892 | X509_REQ *req; |
| 2893 | const unsigned char *pos; |
| 2894 | EVP_PKEY *pkey; |
| 2895 | int res, loc, ret = -1; |
| 2896 | X509_ATTRIBUTE *attr; |
| 2897 | ASN1_TYPE *type; |
| 2898 | ASN1_STRING *str; |
| 2899 | unsigned char *utf8 = NULL; |
| 2900 | unsigned char *cp = NULL; |
| 2901 | size_t cp_len; |
| 2902 | u8 exp_cp[DPP_CP_LEN]; |
| 2903 | unsigned int hash_len = auth->curve->hash_len; |
| 2904 | |
| 2905 | pos = wpabuf_head(csr); |
| 2906 | req = d2i_X509_REQ(NULL, &pos, wpabuf_len(csr)); |
| 2907 | if (!req) { |
| 2908 | wpa_printf(MSG_DEBUG, "DPP: Failed to parse CSR"); |
| 2909 | return -1; |
| 2910 | } |
| 2911 | |
| 2912 | pkey = X509_REQ_get_pubkey(req); |
| 2913 | if (!pkey) { |
| 2914 | wpa_printf(MSG_DEBUG, "DPP: Failed to get public key from CSR"); |
| 2915 | goto fail; |
| 2916 | } |
| 2917 | |
| 2918 | res = X509_REQ_verify(req, pkey); |
| 2919 | EVP_PKEY_free(pkey); |
| 2920 | if (res != 1) { |
| 2921 | wpa_printf(MSG_DEBUG, |
| 2922 | "DPP: CSR does not have a valid signature"); |
| 2923 | goto fail; |
| 2924 | } |
| 2925 | |
| 2926 | loc = X509_REQ_get_attr_by_NID(req, NID_pkcs9_challengePassword, -1); |
| 2927 | if (loc < 0) { |
| 2928 | wpa_printf(MSG_DEBUG, |
| 2929 | "DPP: CSR does not include challengePassword"); |
| 2930 | goto fail; |
| 2931 | } |
| 2932 | |
| 2933 | attr = X509_REQ_get_attr(req, loc); |
| 2934 | if (!attr) { |
| 2935 | wpa_printf(MSG_DEBUG, |
| 2936 | "DPP: Could not get challengePassword attribute"); |
| 2937 | goto fail; |
| 2938 | } |
| 2939 | |
| 2940 | type = X509_ATTRIBUTE_get0_type(attr, 0); |
| 2941 | if (!type) { |
| 2942 | wpa_printf(MSG_DEBUG, |
| 2943 | "DPP: Could not get challengePassword attribute type"); |
| 2944 | goto fail; |
| 2945 | } |
| 2946 | |
| 2947 | res = ASN1_TYPE_get(type); |
| 2948 | /* This is supposed to be UTF8String, but allow other strings as well |
| 2949 | * since challengePassword is using ASCII (base64 encoded). */ |
| 2950 | if (res != V_ASN1_UTF8STRING && res != V_ASN1_PRINTABLESTRING && |
| 2951 | res != V_ASN1_IA5STRING) { |
| 2952 | wpa_printf(MSG_DEBUG, |
| 2953 | "DPP: Unexpected challengePassword attribute type %d", |
| 2954 | res); |
| 2955 | goto fail; |
| 2956 | } |
| 2957 | |
| 2958 | str = X509_ATTRIBUTE_get0_data(attr, 0, res, NULL); |
| 2959 | if (!str) { |
| 2960 | wpa_printf(MSG_DEBUG, |
| 2961 | "DPP: Could not get ASN.1 string for challengePassword"); |
| 2962 | goto fail; |
| 2963 | } |
| 2964 | |
| 2965 | res = ASN1_STRING_to_UTF8(&utf8, str); |
| 2966 | if (res < 0) { |
| 2967 | wpa_printf(MSG_DEBUG, |
| 2968 | "DPP: Could not get UTF8 version of challengePassword"); |
| 2969 | goto fail; |
| 2970 | } |
| 2971 | |
| 2972 | cp = base64_decode((const char *) utf8, res, &cp_len); |
| 2973 | OPENSSL_free(utf8); |
| 2974 | if (!cp) { |
| 2975 | wpa_printf(MSG_DEBUG, |
| 2976 | "DPP: Could not base64 decode challengePassword"); |
| 2977 | goto fail; |
| 2978 | } |
| 2979 | if (cp_len != DPP_CP_LEN) { |
| 2980 | wpa_printf(MSG_DEBUG, |
| 2981 | "DPP: Unexpected cp length (%zu) in CSR challengePassword", |
| 2982 | cp_len); |
| 2983 | goto fail; |
| 2984 | } |
| 2985 | wpa_hexdump_key(MSG_DEBUG, "DPP: cp from CSR challengePassword", |
| 2986 | cp, cp_len); |
| 2987 | |
| 2988 | /* cp = HKDF-Expand(bk, "CSR challengePassword", 64) */ |
| 2989 | if (dpp_hkdf_expand(hash_len, auth->bk, hash_len, |
| 2990 | "CSR challengePassword", exp_cp, DPP_CP_LEN) < 0) |
| 2991 | goto fail; |
| 2992 | wpa_hexdump_key(MSG_DEBUG, |
| 2993 | "DPP: cp = HKDF-Expand(bk, \"CSR challengePassword\", 64)", |
| 2994 | exp_cp, DPP_CP_LEN); |
| 2995 | if (os_memcmp_const(cp, exp_cp, DPP_CP_LEN) != 0) { |
| 2996 | wpa_printf(MSG_DEBUG, |
| 2997 | "DPP: CSR challengePassword does not match calculated cp"); |
| 2998 | goto fail; |
| 2999 | } |
| 3000 | |
| 3001 | ret = 0; |
| 3002 | fail: |
| 3003 | os_free(cp); |
| 3004 | X509_REQ_free(req); |
| 3005 | return ret; |
| 3006 | } |
| 3007 | |
| 3008 | |
| 3009 | struct dpp_reconfig_id * dpp_gen_reconfig_id(const u8 *csign_key, |
| 3010 | size_t csign_key_len, |
| 3011 | const u8 *pp_key, |
| 3012 | size_t pp_key_len) |
| 3013 | { |
| 3014 | const unsigned char *p; |
| 3015 | EVP_PKEY *csign = NULL, *ppkey = NULL; |
| 3016 | struct dpp_reconfig_id *id = NULL; |
| 3017 | BN_CTX *ctx = NULL; |
| 3018 | BIGNUM *bn = NULL, *q = NULL; |
| 3019 | const EC_KEY *eckey; |
| 3020 | const EC_GROUP *group; |
| 3021 | EC_POINT *e_id = NULL; |
| 3022 | |
| 3023 | p = csign_key; |
| 3024 | csign = d2i_PUBKEY(NULL, &p, csign_key_len); |
| 3025 | if (!csign) |
| 3026 | goto fail; |
| 3027 | |
| 3028 | if (!pp_key) |
| 3029 | goto fail; |
| 3030 | p = pp_key; |
| 3031 | ppkey = d2i_PUBKEY(NULL, &p, pp_key_len); |
| 3032 | if (!ppkey) |
| 3033 | goto fail; |
| 3034 | |
| 3035 | eckey = EVP_PKEY_get0_EC_KEY(csign); |
| 3036 | if (!eckey) |
| 3037 | goto fail; |
| 3038 | group = EC_KEY_get0_group(eckey); |
| 3039 | if (!group) |
| 3040 | goto fail; |
| 3041 | |
| 3042 | e_id = EC_POINT_new(group); |
| 3043 | ctx = BN_CTX_new(); |
| 3044 | bn = BN_new(); |
| 3045 | q = BN_new(); |
| 3046 | if (!e_id || !ctx || !bn || !q || |
| 3047 | !EC_GROUP_get_order(group, q, ctx) || |
| 3048 | !BN_rand_range(bn, q) || |
| 3049 | !EC_POINT_mul(group, e_id, bn, NULL, NULL, ctx)) |
| 3050 | goto fail; |
| 3051 | |
| 3052 | dpp_debug_print_point("DPP: Generated random point E-id", group, e_id); |
| 3053 | |
| 3054 | id = os_zalloc(sizeof(*id)); |
| 3055 | if (!id) |
| 3056 | goto fail; |
| 3057 | id->group = group; |
| 3058 | id->e_id = e_id; |
| 3059 | e_id = NULL; |
| 3060 | id->csign = csign; |
| 3061 | csign = NULL; |
| 3062 | id->pp_key = ppkey; |
| 3063 | ppkey = NULL; |
| 3064 | fail: |
| 3065 | EC_POINT_free(e_id); |
| 3066 | EVP_PKEY_free(csign); |
| 3067 | EVP_PKEY_free(ppkey); |
| 3068 | BN_clear_free(bn); |
| 3069 | BN_CTX_free(ctx); |
| 3070 | return id; |
| 3071 | } |
| 3072 | |
| 3073 | |
| 3074 | static EVP_PKEY * dpp_pkey_from_point(const EC_GROUP *group, |
| 3075 | const EC_POINT *point) |
| 3076 | { |
| 3077 | EC_KEY *eckey; |
| 3078 | EVP_PKEY *pkey = NULL; |
| 3079 | |
| 3080 | eckey = EC_KEY_new(); |
| 3081 | if (!eckey || |
| 3082 | EC_KEY_set_group(eckey, group) != 1 || |
| 3083 | EC_KEY_set_public_key(eckey, point) != 1) { |
| 3084 | wpa_printf(MSG_ERROR, |
| 3085 | "DPP: Failed to set EC_KEY: %s", |
| 3086 | ERR_error_string(ERR_get_error(), NULL)); |
| 3087 | goto fail; |
| 3088 | } |
| 3089 | EC_KEY_set_asn1_flag(eckey, OPENSSL_EC_NAMED_CURVE); |
| 3090 | |
| 3091 | pkey = EVP_PKEY_new(); |
| 3092 | if (!pkey || EVP_PKEY_set1_EC_KEY(pkey, eckey) != 1) { |
| 3093 | wpa_printf(MSG_ERROR, "DPP: Could not create EVP_PKEY"); |
| 3094 | EVP_PKEY_free(pkey); |
| 3095 | pkey = NULL; |
| 3096 | goto fail; |
| 3097 | } |
| 3098 | |
| 3099 | fail: |
| 3100 | EC_KEY_free(eckey); |
| 3101 | return pkey; |
| 3102 | } |
| 3103 | |
| 3104 | |
| 3105 | int dpp_update_reconfig_id(struct dpp_reconfig_id *id) |
| 3106 | { |
| 3107 | BN_CTX *ctx = NULL; |
| 3108 | BIGNUM *bn = NULL, *q = NULL; |
| 3109 | EC_POINT *e_prime_id = NULL, *a_nonce = NULL; |
| 3110 | int ret = -1; |
| 3111 | const EC_KEY *pp; |
| 3112 | const EC_POINT *pp_point; |
| 3113 | |
| 3114 | pp = EVP_PKEY_get0_EC_KEY(id->pp_key); |
| 3115 | if (!pp) |
| 3116 | goto fail; |
| 3117 | pp_point = EC_KEY_get0_public_key(pp); |
| 3118 | e_prime_id = EC_POINT_new(id->group); |
| 3119 | a_nonce = EC_POINT_new(id->group); |
| 3120 | ctx = BN_CTX_new(); |
| 3121 | bn = BN_new(); |
| 3122 | q = BN_new(); |
| 3123 | /* Generate random 0 <= a-nonce < q |
| 3124 | * A-NONCE = a-nonce * G |
| 3125 | * E'-id = E-id + a-nonce * P_pk */ |
| 3126 | if (!pp_point || !e_prime_id || !a_nonce || !ctx || !bn || !q || |
| 3127 | !EC_GROUP_get_order(id->group, q, ctx) || |
| 3128 | !BN_rand_range(bn, q) || /* bn = a-nonce */ |
| 3129 | !EC_POINT_mul(id->group, a_nonce, bn, NULL, NULL, ctx) || |
| 3130 | !EC_POINT_mul(id->group, e_prime_id, NULL, pp_point, bn, ctx) || |
| 3131 | !EC_POINT_add(id->group, e_prime_id, id->e_id, e_prime_id, ctx)) |
| 3132 | goto fail; |
| 3133 | |
| 3134 | dpp_debug_print_point("DPP: Generated A-NONCE", id->group, a_nonce); |
| 3135 | dpp_debug_print_point("DPP: Encrypted E-id to E'-id", |
| 3136 | id->group, e_prime_id); |
| 3137 | |
| 3138 | EVP_PKEY_free(id->a_nonce); |
| 3139 | EVP_PKEY_free(id->e_prime_id); |
| 3140 | id->a_nonce = dpp_pkey_from_point(id->group, a_nonce); |
| 3141 | id->e_prime_id = dpp_pkey_from_point(id->group, e_prime_id); |
| 3142 | if (!id->a_nonce || !id->e_prime_id) |
| 3143 | goto fail; |
| 3144 | |
| 3145 | ret = 0; |
| 3146 | |
| 3147 | fail: |
| 3148 | EC_POINT_free(e_prime_id); |
| 3149 | EC_POINT_free(a_nonce); |
| 3150 | BN_clear_free(bn); |
| 3151 | BN_CTX_free(ctx); |
| 3152 | return ret; |
| 3153 | } |
| 3154 | |
| 3155 | |
| 3156 | void dpp_free_reconfig_id(struct dpp_reconfig_id *id) |
| 3157 | { |
| 3158 | if (id) { |
| 3159 | EC_POINT_clear_free(id->e_id); |
| 3160 | EVP_PKEY_free(id->csign); |
| 3161 | EVP_PKEY_free(id->a_nonce); |
| 3162 | EVP_PKEY_free(id->e_prime_id); |
| 3163 | EVP_PKEY_free(id->pp_key); |
| 3164 | os_free(id); |
| 3165 | } |
| 3166 | } |
| 3167 | |
| 3168 | |
| 3169 | EC_POINT * dpp_decrypt_e_id(EVP_PKEY *ppkey, EVP_PKEY *a_nonce, |
| 3170 | EVP_PKEY *e_prime_id) |
| 3171 | { |
| 3172 | const EC_KEY *pp_ec, *a_nonce_ec, *e_prime_id_ec; |
| 3173 | const BIGNUM *pp_bn; |
| 3174 | const EC_GROUP *group; |
| 3175 | EC_POINT *e_id = NULL; |
| 3176 | const EC_POINT *a_nonce_point, *e_prime_id_point; |
| 3177 | BN_CTX *ctx = NULL; |
| 3178 | |
| 3179 | if (!ppkey) |
| 3180 | return NULL; |
| 3181 | |
| 3182 | /* E-id = E'-id - s_C * A-NONCE */ |
| 3183 | pp_ec = EVP_PKEY_get0_EC_KEY(ppkey); |
| 3184 | a_nonce_ec = EVP_PKEY_get0_EC_KEY(a_nonce); |
| 3185 | e_prime_id_ec = EVP_PKEY_get0_EC_KEY(e_prime_id); |
| 3186 | if (!pp_ec || !a_nonce_ec || !e_prime_id_ec) |
| 3187 | return NULL; |
| 3188 | pp_bn = EC_KEY_get0_private_key(pp_ec); |
| 3189 | group = EC_KEY_get0_group(pp_ec); |
| 3190 | a_nonce_point = EC_KEY_get0_public_key(a_nonce_ec); |
| 3191 | e_prime_id_point = EC_KEY_get0_public_key(e_prime_id_ec); |
| 3192 | ctx = BN_CTX_new(); |
| 3193 | if (!pp_bn || !group || !a_nonce_point || !e_prime_id_point || !ctx) |
| 3194 | goto fail; |
| 3195 | e_id = EC_POINT_new(group); |
| 3196 | if (!e_id || |
| 3197 | !EC_POINT_mul(group, e_id, NULL, a_nonce_point, pp_bn, ctx) || |
| 3198 | !EC_POINT_invert(group, e_id, ctx) || |
| 3199 | !EC_POINT_add(group, e_id, e_prime_id_point, e_id, ctx)) { |
| 3200 | EC_POINT_clear_free(e_id); |
| 3201 | goto fail; |
| 3202 | } |
| 3203 | |
| 3204 | dpp_debug_print_point("DPP: Decrypted E-id", group, e_id); |
| 3205 | |
| 3206 | fail: |
| 3207 | BN_CTX_free(ctx); |
| 3208 | return e_id; |
| 3209 | } |
| 3210 | |
Hai Shalom | 4fbc08f | 2020-05-18 12:37:00 -0700 | [diff] [blame] | 3211 | #endif /* CONFIG_DPP2 */ |
| 3212 | |
| 3213 | |
| 3214 | #ifdef CONFIG_TESTING_OPTIONS |
| 3215 | |
| 3216 | int dpp_test_gen_invalid_key(struct wpabuf *msg, |
| 3217 | const struct dpp_curve_params *curve) |
| 3218 | { |
| 3219 | BN_CTX *ctx; |
| 3220 | BIGNUM *x, *y; |
| 3221 | int ret = -1; |
| 3222 | EC_GROUP *group; |
| 3223 | EC_POINT *point; |
| 3224 | |
| 3225 | group = EC_GROUP_new_by_curve_name(OBJ_txt2nid(curve->name)); |
| 3226 | if (!group) |
| 3227 | return -1; |
| 3228 | |
| 3229 | ctx = BN_CTX_new(); |
| 3230 | point = EC_POINT_new(group); |
| 3231 | x = BN_new(); |
| 3232 | y = BN_new(); |
| 3233 | if (!ctx || !point || !x || !y) |
| 3234 | goto fail; |
| 3235 | |
| 3236 | if (BN_rand(x, curve->prime_len * 8, 0, 0) != 1) |
| 3237 | goto fail; |
| 3238 | |
| 3239 | /* Generate a random y coordinate that results in a point that is not |
| 3240 | * on the curve. */ |
| 3241 | for (;;) { |
| 3242 | if (BN_rand(y, curve->prime_len * 8, 0, 0) != 1) |
| 3243 | goto fail; |
| 3244 | |
| 3245 | if (EC_POINT_set_affine_coordinates_GFp(group, point, x, y, |
| 3246 | ctx) != 1) { |
| 3247 | #if OPENSSL_VERSION_NUMBER >= 0x10100000L || defined(OPENSSL_IS_BORINGSSL) |
| 3248 | /* Unlike older OpenSSL versions, OpenSSL 1.1.1 and BoringSSL |
| 3249 | * return an error from EC_POINT_set_affine_coordinates_GFp() |
| 3250 | * when the point is not on the curve. */ |
| 3251 | break; |
| 3252 | #else /* >=1.1.0 or OPENSSL_IS_BORINGSSL */ |
| 3253 | goto fail; |
| 3254 | #endif /* >= 1.1.0 or OPENSSL_IS_BORINGSSL */ |
| 3255 | } |
| 3256 | |
| 3257 | if (!EC_POINT_is_on_curve(group, point, ctx)) |
| 3258 | break; |
| 3259 | } |
| 3260 | |
| 3261 | if (dpp_bn2bin_pad(x, wpabuf_put(msg, curve->prime_len), |
| 3262 | curve->prime_len) < 0 || |
| 3263 | dpp_bn2bin_pad(y, wpabuf_put(msg, curve->prime_len), |
| 3264 | curve->prime_len) < 0) |
| 3265 | goto fail; |
| 3266 | |
| 3267 | ret = 0; |
| 3268 | fail: |
| 3269 | if (ret < 0) |
| 3270 | wpa_printf(MSG_INFO, "DPP: Failed to generate invalid key"); |
| 3271 | BN_free(x); |
| 3272 | BN_free(y); |
| 3273 | EC_POINT_free(point); |
| 3274 | BN_CTX_free(ctx); |
| 3275 | EC_GROUP_free(group); |
| 3276 | |
| 3277 | return ret; |
| 3278 | } |
| 3279 | |
| 3280 | |
| 3281 | char * dpp_corrupt_connector_signature(const char *connector) |
| 3282 | { |
| 3283 | char *tmp, *pos, *signed3 = NULL; |
| 3284 | unsigned char *signature = NULL; |
| 3285 | size_t signature_len = 0, signed3_len; |
| 3286 | |
| 3287 | tmp = os_zalloc(os_strlen(connector) + 5); |
| 3288 | if (!tmp) |
| 3289 | goto fail; |
| 3290 | os_memcpy(tmp, connector, os_strlen(connector)); |
| 3291 | |
| 3292 | pos = os_strchr(tmp, '.'); |
| 3293 | if (!pos) |
| 3294 | goto fail; |
| 3295 | |
| 3296 | pos = os_strchr(pos + 1, '.'); |
| 3297 | if (!pos) |
| 3298 | goto fail; |
| 3299 | pos++; |
| 3300 | |
| 3301 | wpa_printf(MSG_DEBUG, "DPP: Original base64url encoded signature: %s", |
| 3302 | pos); |
| 3303 | signature = base64_url_decode(pos, os_strlen(pos), &signature_len); |
| 3304 | if (!signature || signature_len == 0) |
| 3305 | goto fail; |
| 3306 | wpa_hexdump(MSG_DEBUG, "DPP: Original Connector signature", |
| 3307 | signature, signature_len); |
| 3308 | signature[signature_len - 1] ^= 0x01; |
| 3309 | wpa_hexdump(MSG_DEBUG, "DPP: Corrupted Connector signature", |
| 3310 | signature, signature_len); |
| 3311 | signed3 = base64_url_encode(signature, signature_len, &signed3_len); |
| 3312 | if (!signed3) |
| 3313 | goto fail; |
| 3314 | os_memcpy(pos, signed3, signed3_len); |
| 3315 | pos[signed3_len] = '\0'; |
| 3316 | wpa_printf(MSG_DEBUG, "DPP: Corrupted base64url encoded signature: %s", |
| 3317 | pos); |
| 3318 | |
| 3319 | out: |
| 3320 | os_free(signature); |
| 3321 | os_free(signed3); |
| 3322 | return tmp; |
| 3323 | fail: |
| 3324 | os_free(tmp); |
| 3325 | tmp = NULL; |
| 3326 | goto out; |
| 3327 | } |
| 3328 | |
| 3329 | #endif /* CONFIG_TESTING_OPTIONS */ |