X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/7bb9d33e2c2dccd700db53468d58e7b6f5b796c6..refs/pull/304/head:/common/iso15693tools.c?ds=sidebyside diff --git a/common/iso15693tools.c b/common/iso15693tools.c index add0ba69..26e636ca 100644 --- a/common/iso15693tools.c +++ b/common/iso15693tools.c @@ -12,6 +12,9 @@ #include //#include "iso15693tools.h" +#define POLY 0x8408 + + // The CRC as described in ISO 15693-Part 3-Annex C // v buffer with data // n length @@ -63,5 +66,31 @@ char* Iso15693sprintUID(char *target,uint8_t *uid) { return target; } +uint16_t iclass_crc16(char *data_p, unsigned short length) +{ + unsigned char i; + unsigned int data; + uint16_t crc = 0xffff; + + if (length == 0) + return (~crc); + + do + { + for (i=0, data=(unsigned int)0xff & *data_p++; + i < 8; + i++, data >>= 1) + { + if ((crc & 0x0001) ^ (data & 0x0001)) + crc = (crc >> 1) ^ POLY; + else crc >>= 1; + } + } while (--length); + crc = ~crc; + data = crc; + crc = (crc << 8) | (data >> 8 & 0xff); + crc = crc ^ 0xBC3; + return (crc); +}