fix memmove if len=0

This commit is contained in:
merlokk 2019-02-05 18:39:03 +02:00
parent 0e5d896893
commit 69f3e65dd0

View file

@ -2266,32 +2266,34 @@ int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, bool send_chaining, void *data, u
iso14a_set_timeout(save_iso14a_timeout);
}
// if we received an I- or R(ACK)-Block with a block number equal to the
// current block number, toggle the current block number
// if we received an I- or R(ACK)-Block with a block number equal to the
// current block number, toggle the current block number
if (len >= 3 // PCB+CRC = 3 bytes
&& ((data_bytes[0] & 0xC0) == 0 // I-Block
|| (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
&& (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
{
iso14_pcb_blocknum ^= 1;
}
{
iso14_pcb_blocknum ^= 1;
}
// if we received I-block with chaining we need to send ACK and receive another block of data
if (res)
*res = data_bytes[0];
// crc check
if (len >=3 && !check_crc(CRC_14443_A, data_bytes, len)) {
if (len >= 3 && !check_crc(CRC_14443_A, data_bytes, len)) {
return -1;
}
}
// cut frame byte
len -= 1;
// memmove(data_bytes, data_bytes + 1, len);
for (int i = 0; i < len; i++)
data_bytes[i] = data_bytes[i + 1];
if (len) {
// cut frame byte
len -= 1;
// memmove(data_bytes, data_bytes + 1, len);
for (int i = 0; i < len; i++)
data_bytes[i] = data_bytes[i + 1];
}
return len;
}