diff options
Diffstat (limited to 'release/src/linux/linux/include/net/checksum.h')
| -rw-r--r-- | release/src/linux/linux/include/net/checksum.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/release/src/linux/linux/include/net/checksum.h b/release/src/linux/linux/include/net/checksum.h new file mode 100644 index 00000000..6a16809c --- /dev/null +++ b/release/src/linux/linux/include/net/checksum.h @@ -0,0 +1,154 @@ +/* + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * Checksumming functions for IP, TCP, UDP and so on + * + * Authors: Jorge Cwik, <jorge@laser.satlink.net> + * Arnt Gulbrandsen, <agulbra@nvg.unit.no> + * Borrows very liberally from tcp.c and ip.c, see those + * files for more names. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +/* + * Fixes: + * + * Ralf Baechle : generic ipv6 checksum + * <ralf@waldorf-gmbh.de> + */ + +#ifndef _CHECKSUM_H +#define _CHECKSUM_H + +#include <asm/types.h> +#include <asm/byteorder.h> +#include <net/ip.h> +#include <asm/uaccess.h> +#include <asm/checksum.h> + +#ifndef _HAVE_ARCH_IPV6_CSUM + +static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, + struct in6_addr *daddr, + __u16 len, + unsigned short proto, + unsigned int csum) +{ + + int carry; + __u32 ulen; + __u32 uproto; + + csum += saddr->s6_addr32[0]; + carry = (csum < saddr->s6_addr32[0]); + csum += carry; + + csum += saddr->s6_addr32[1]; + carry = (csum < saddr->s6_addr32[1]); + csum += carry; + + csum += saddr->s6_addr32[2]; + carry = (csum < saddr->s6_addr32[2]); + csum += carry; + + csum += saddr->s6_addr32[3]; + carry = (csum < saddr->s6_addr32[3]); + csum += carry; + + csum += daddr->s6_addr32[0]; + carry = (csum < daddr->s6_addr32[0]); + csum += carry; + + csum += daddr->s6_addr32[1]; + carry = (csum < daddr->s6_addr32[1]); + csum += carry; + + csum += daddr->s6_addr32[2]; + carry = (csum < daddr->s6_addr32[2]); + csum += carry; + + csum += daddr->s6_addr32[3]; + carry = (csum < daddr->s6_addr32[3]); + csum += carry; + + ulen = htonl((__u32) len); + csum += ulen; + carry = (csum < ulen); + csum += carry; + + uproto = htonl(proto); + csum += uproto; + carry = (csum < uproto); + csum += carry; + + return csum_fold(csum); +} + +#endif + +#ifndef _HAVE_ARCH_COPY_AND_CSUM_FROM_USER +static inline +unsigned int csum_and_copy_from_user (const char *src, char *dst, + int len, int sum, int *err_ptr) +{ + if (verify_area(VERIFY_READ, src, len) == 0) + return csum_partial_copy_from_user(src, dst, len, sum, err_ptr); + + if (len) + *err_ptr = -EFAULT; + + return sum; +} +#endif + +#ifndef HAVE_CSUM_COPY_USER +static __inline__ unsigned int csum_and_copy_to_user +(const char *src, char *dst, int len, unsigned int sum, int *err_ptr) +{ + sum = csum_partial(src, len, sum); + + if (access_ok(VERIFY_WRITE, dst, len)) { + if (copy_to_user(dst, src, len) == 0) + return sum; + } + if (len) + *err_ptr = -EFAULT; + + return -1; /* invalid checksum */ +} +#endif + +static inline unsigned int csum_add(unsigned int csum, unsigned int addend) +{ + csum += addend; + return csum + (csum < addend); +} + +static inline unsigned int csum_sub(unsigned int csum, unsigned int addend) +{ + return csum_add(csum, ~addend); +} + +static inline unsigned int +csum_block_add(unsigned int csum, unsigned int csum2, int offset) +{ + if (offset&1) + csum2 = ((csum2&0xFF00FF)<<8)+((csum2>>8)&0xFF00FF); + return csum_add(csum, csum2); +} + +static inline unsigned int +csum_block_sub(unsigned int csum, unsigned int csum2, int offset) +{ + if (offset&1) + csum2 = ((csum2&0xFF00FF)<<8)+((csum2>>8)&0xFF00FF); + return csum_sub(csum, csum2); +} + +#endif |