diff options
Diffstat (limited to 'isisd/iso_checksum.c')
| -rw-r--r-- | isisd/iso_checksum.c | 37 |
1 files changed, 9 insertions, 28 deletions
diff --git a/isisd/iso_checksum.c b/isisd/iso_checksum.c index 16f18e50..abd101b9 100644 --- a/isisd/iso_checksum.c +++ b/isisd/iso_checksum.c @@ -23,6 +23,7 @@ #include <zebra.h> #include "iso_checksum.h" +#include "checksum.h" /* * Calculations of the OSI checksum. @@ -47,14 +48,10 @@ int iso_csum_verify (u_char * buffer, int len, uint16_t * csum) { - u_int8_t *p; + u_int16_t checksum; u_int32_t c0; u_int32_t c1; - u_int16_t checksum; - int i, partial_len; - p = buffer; - checksum = 0; c0 = *csum & 0xff00; c1 = *csum & 0x00ff; @@ -70,33 +67,15 @@ iso_csum_verify (u_char * buffer, int len, uint16_t * csum) if (c0 == 0 || c1 == 0) return 1; - /* - * Otherwise initialize to zero and calculate... - */ - c0 = 0; - c1 = 0; - - while (len) - { - partial_len = MIN(len, 5803); - - for (i = 0; i < partial_len; i++) - { - c0 = c0 + *(p++); - c1 += c0; - } + /* Offset of checksum from the start of the buffer */ + int offset = (u_char *) csum - buffer; - c0 = c0 % 255; - c1 = c1 % 255; - - len -= partial_len; - } - - if (c0 == 0 && c1 == 0) + checksum = fletcher_checksum(buffer, len, offset); + if (checksum == *csum) return 0; - return 1; } +<<<<<<< HEAD:isisd/iso_checksum.c /* * Creates the checksum. *csum points to the position of the checksum in the @@ -191,3 +170,5 @@ iso_csum_create (u_char * buffer, int len, u_int16_t n) /* return the checksum for user usage */ return checksum; } +======= +>>>>>>> 41dc3488cf127a1e23333459a0c316ded67f7ff3:isisd/iso_checksum.c |