ev2 auth 1st and 2nd works

This commit is contained in:
merlokk 2021-07-30 16:38:00 +03:00
commit e2f0d62458
3 changed files with 17 additions and 26 deletions

View file

@ -1084,7 +1084,7 @@ static int DesfireAuthenticateEV2(DesfireContext *dctx, DesfireSecureChannel sec
uint8_t both[CRYPTO_AES_BLOCK_SIZE * 2 + 1] = {0}; // ek/dk_keyNo(RndA+RndB')
uint8_t subcommand = firstauth ? MFDES_AUTHENTICATE_EV2F : MFDES_AUTHENTICATE_EV2NF;
uint8_t *key = firstauth ? dctx->key : dctx->sessionKeyEnc;
uint8_t *key = dctx->key;
size_t recv_len = 0;
uint8_t respcode = 0;
@ -1123,8 +1123,6 @@ static int DesfireAuthenticateEV2(DesfireContext *dctx, DesfireSecureChannel sec
PrintAndLogEx(DEBUG, "encRndB: %s", sprint_hex(encRndB, CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(DEBUG, "RndB: %s", sprint_hex(RndB, CRYPTO_AES_BLOCK_SIZE));
}
PrintAndLogEx(INFO, "encRndB: %s", sprint_hex(encRndB, 16));
PrintAndLogEx(INFO, "RndB: %s", sprint_hex(RndB, 16));
// - Rotate RndB by 8 bits
memcpy(rotRndB, RndB, CRYPTO_AES_BLOCK_SIZE);
@ -1141,18 +1139,12 @@ PrintAndLogEx(INFO, "RndB: %s", sprint_hex(RndB, 16));
PrintAndLogEx(DEBUG, "Both: %s", sprint_hex(tmp, CRYPTO_AES_BLOCK_SIZE * 2));
}
PrintAndLogEx(INFO, "rotRndB: %s", sprint_hex(rotRndB, CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(INFO, "Both: %s", sprint_hex(tmp, CRYPTO_AES_BLOCK_SIZE * 2));
if (aes_encode(IV, key, tmp, both, CRYPTO_AES_BLOCK_SIZE * 2))
return 6;
if (g_debugMode > 1) {
PrintAndLogEx(DEBUG, "EncBoth: %s", sprint_hex(both, CRYPTO_AES_BLOCK_SIZE * 2));
}
PrintAndLogEx(INFO, "EncBoth: %s", sprint_hex(both, CRYPTO_AES_BLOCK_SIZE * 2));
res = DesfireExchangeEx(false, dctx, MFDES_ADDITIONAL_FRAME, both, CRYPTO_AES_BLOCK_SIZE * 2, &respcode, recv_data, &recv_len, false, 0);
if (res != PM3_SUCCESS) {
return 7;
@ -1169,45 +1161,39 @@ PrintAndLogEx(INFO, "EncBoth: %s", sprint_hex(both, CRYPTO_AES_BLOCK_SIZE * 2));
// Part 4
memcpy(encRndA, recv_data, CRYPTO_AES_BLOCK_SIZE);
PrintAndLogEx(INFO, "encRndA : %s", sprint_hex(encRndA, CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(INFO, "IV : %s", sprint_hex(IV, CRYPTO_AES_BLOCK_SIZE));
uint8_t data[32] = {0};
if (aes_decode(IV, key, recv_data, data, recv_len))
return 10;
PrintAndLogEx(INFO, "data : %s", sprint_hex(data, CRYPTO_AES_BLOCK_SIZE * 2));
rol(RndA, CRYPTO_AES_BLOCK_SIZE);
PrintAndLogEx(INFO, "Expected_RndA : %s", sprint_hex(RndA, CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(INFO, "Generated_RndA : %s", sprint_hex(&data[4], CRYPTO_AES_BLOCK_SIZE));
uint8_t *recRndA = (firstauth) ? &data[4] : data;
if (memcmp(RndA, &data[4], CRYPTO_AES_BLOCK_SIZE) != 0) {
if (memcmp(RndA, recRndA, CRYPTO_AES_BLOCK_SIZE) != 0) {
if (g_debugMode > 1) {
PrintAndLogEx(DEBUG, "Expected_RndA : %s", sprint_hex(RndA, CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(DEBUG, "Generated_RndA : %s", sprint_hex(&data[4], CRYPTO_AES_BLOCK_SIZE));
PrintAndLogEx(DEBUG, "Generated_RndA : %s", sprint_hex(recRndA, CRYPTO_AES_BLOCK_SIZE));
}
return 11;
}
if (verbose) {
PrintAndLogEx(INFO, "TI : %s", sprint_hex(data, 4));
PrintAndLogEx(INFO, "pic : %s", sprint_hex(&data[20], 6));
PrintAndLogEx(INFO, "pcd : %s", sprint_hex(&data[26], 6));
}
if (firstauth) {
dctx->cmdCntr = 0;
memcpy(dctx->TI, data, 4);
}
memset(dctx->IV, 0, DESFIRE_MAX_KEY_SIZE);
DesfireClearIV(dctx);
DesfireGenSessionKeyEV2(dctx->key, RndA, RndB, true, dctx->sessionKeyEnc);
DesfireGenSessionKeyEV2(dctx->key, RndA, RndB, false, dctx->sessionKeyMAC);
dctx->secureChannel = secureChannel;
if (verbose) {
if (firstauth) {
PrintAndLogEx(INFO, "TI : %s", sprint_hex(data, 4));
PrintAndLogEx(INFO, "pic : %s", sprint_hex(&data[20], 6));
PrintAndLogEx(INFO, "pcd : %s", sprint_hex(&data[26], 6));
} else {
PrintAndLogEx(INFO, "TI : %s", sprint_hex(dctx->TI, 4));
}
PrintAndLogEx(INFO, "session key ENC: %s", sprint_hex(dctx->sessionKeyEnc, 16));
PrintAndLogEx(INFO, "session key MAC: %s", sprint_hex(dctx->sessionKeyMAC, 16));
}

View file

@ -62,6 +62,10 @@ void DesfireClearSession(DesfireContext *ctx) {
memset(ctx->TI, 0, sizeof(ctx->TI));
}
void DesfireClearIV(DesfireContext *ctx) {
memset(ctx->IV, 0, sizeof(ctx->IV));
}
void DesfireSetKey(DesfireContext *ctx, uint8_t keyNum, enum DESFIRE_CRYPTOALGO keyType, uint8_t *key) {
DesfireClearContext(ctx);

View file

@ -88,6 +88,7 @@ typedef struct DesfireContextS {
void DesfireClearContext(DesfireContext *ctx);
void DesfireClearSession(DesfireContext *ctx);
void DesfireClearIV(DesfireContext *ctx);
void DesfireSetKey(DesfireContext *ctx, uint8_t keyNum, enum DESFIRE_CRYPTOALGO keyType, uint8_t *key);
void DesfireSetCommandSet(DesfireContext *ctx, DesfireCommandSet cmdSet);
void DesfireSetCommMode(DesfireContext *ctx, DesfireCommunicationMode commMode);