int main()
{
LOG_VAR_HEX(crc32("123456789", 9));
LOG_VAR_HEX(crc16("123456789", 9));
LOG_VAR_HEX(crc24("123456789", 9));
return 0;
}
/*!
* @brief Calculates and reports the Information Block Checksum.
* @return #mxt_rc
*/
static int calculate_crc(struct mxt_device *mxt, uint32_t read_crc,
uint8_t *base_addr, size_t size)
{
uint32_t calc_crc = 0; /* Checksum calculated by the driver code */
uint16_t crc_byte_index = 0;
/* Call the CRC function crc24() iteratively to calculate the CRC,
* passing it two characters at a time. */
while (crc_byte_index < ((size % 2) ? (size - 1) : size))
{
calc_crc = crc24(calc_crc, *(base_addr + crc_byte_index),
*(base_addr + crc_byte_index + 1));
crc_byte_index += 2;
}
/* Call crc24() for the final byte, plus an extra
* 0 value byte to make the sequence even if it's odd */
if (size % 2)
{
calc_crc = crc24(calc_crc, *(base_addr + crc_byte_index), 0);
}
/* Mask 32-bit calculated checksum to 24-bit */
calc_crc &= calc_crc & 0x00FFFFFF;
/* A zero CRC indicates a communications error */
if (calc_crc == 0)
{
mxt_err(mxt->ctx, "Information Block Checksum zero");
return MXT_ERROR_IO;
}
/* Compare the read checksum with calculated checksum */
if (read_crc != calc_crc)
{
mxt_err(mxt->ctx, "Information Block Checksum error calc=%06X read=%06X",
calc_crc, read_crc);
return MXT_ERROR_INFO_CHECKSUM_MISMATCH;
}
mxt_dbg(mxt->ctx, "Information Block Checksum verified %06X", calc_crc);
return MXT_SUCCESS;
}
static unsigned char *
unarmor(char *pubkey, int *pktlp)
{
char *p;
int l, eof;
unsigned char *buf, *bp;
unsigned int v;
*pktlp = 0;
while (strncmp(pubkey, "-----BEGIN PGP PUBLIC KEY BLOCK-----", 36) != 0)
{
pubkey = strchr(pubkey, '\n');
if (!pubkey)
return 0;
pubkey++;
}
pubkey = strchr(pubkey, '\n');
if (!pubkey++)
return 0;
/* skip header lines */
for (;;)
{
while (*pubkey == ' ' || *pubkey == '\t')
pubkey++;
if (*pubkey == '\n')
break;
pubkey = strchr(pubkey, '\n');
if (!pubkey++)
return 0;
}
pubkey++;
p = strchr(pubkey, '=');
if (!p)
return 0;
l = p - pubkey;
bp = buf = solv_malloc(l * 3 / 4 + 4);
eof = 0;
while (!eof)
{
pubkey = r64dec1(pubkey, &v, &eof);
if (!pubkey)
{
solv_free(buf);
return 0;
}
*bp++ = v >> 16;
*bp++ = v >> 8;
*bp++ = v;
}
while (*pubkey == ' ' || *pubkey == '\t' || *pubkey == '\n' || *pubkey == '\r')
pubkey++;
bp -= eof;
if (*pubkey != '=' || (pubkey = r64dec1(pubkey + 1, &v, &eof)) == 0)
{
solv_free(buf);
return 0;
}
if (v != crc24(buf, bp - buf))
{
solv_free(buf);
return 0;
}
while (*pubkey == ' ' || *pubkey == '\t' || *pubkey == '\n' || *pubkey == '\r')
pubkey++;
if (strncmp(pubkey, "-----END PGP PUBLIC KEY BLOCK-----", 34) != 0)
{
solv_free(buf);
return 0;
}
*pktlp = bp - buf;
return buf;
}
