diff options
Diffstat (limited to 'sys/contrib/pf/netinet/in4_cksum.c')
| -rw-r--r-- | sys/contrib/pf/netinet/in4_cksum.c | 127 |
1 files changed, 14 insertions, 113 deletions
diff --git a/sys/contrib/pf/netinet/in4_cksum.c b/sys/contrib/pf/netinet/in4_cksum.c index 1c40f2e..24a04d0 100644 --- a/sys/contrib/pf/netinet/in4_cksum.c +++ b/sys/contrib/pf/netinet/in4_cksum.c @@ -1,3 +1,4 @@ +/* $FreeBSD$ */ /* $OpenBSD: in4_cksum.c,v 1.7 2003/06/02 23:28:13 millert Exp $ */ /* $KAME: in4_cksum.c,v 1.10 2001/11/30 10:06:15 itojun Exp $ */ /* $NetBSD: in_cksum.c,v 1.13 1996/10/13 02:03:03 christos Exp $ */ @@ -63,52 +64,37 @@ */ #include <sys/param.h> -#include <sys/mbuf.h> #include <sys/systm.h> -#include <sys/socket.h> -#include <net/route.h> +#include <sys/mbuf.h> + #include <netinet/in.h> #include <netinet/in_systm.h> #include <netinet/ip.h> #include <netinet/ip_var.h> -/* - * Checksum routine for Internet Protocol family headers (Portable Version). - * This is only for IPv4 pseudo header checksum. - * No need to clear non-pseudo-header fields in IPv4 header. - * len is for actual payload size, and does not include IPv4 header and - * skipped header chain (off + len should be equal to the whole packet). - * - * This routine is very heavily used in the network - * code and should be modified for each CPU to be as fast as possible. - */ +#include <machine/in_cksum.h> #define ADDCARRY(x) (x > 65535 ? x -= 65535 : x) #define REDUCE {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);} +int in4_cksum(struct mbuf *, u_int8_t, int, int); + int -in4_cksum(m, nxt, off, len) - struct mbuf *m; - u_int8_t nxt; - int off, len; +in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len) { - u_int16_t *w; - int sum = 0; - int mlen = 0; - int byte_swapped = 0; union { struct ipovly ipov; u_int16_t w[10]; } u; union { - u_int8_t c[2]; - u_int16_t s; - } s_util; - union { u_int16_t s[2]; u_int32_t l; } l_util; + u_int16_t *w; + int psum; + int sum = 0; + if (nxt != 0) { /* pseudo header */ if (off < sizeof(struct ipovly)) @@ -126,94 +112,9 @@ in4_cksum(m, nxt, off, len) sum += w[5]; sum += w[6]; sum += w[7]; sum += w[8]; sum += w[9]; } - /* skip unnecessary part */ - while (m && off > 0) { - if (m->m_len > off) - break; - off -= m->m_len; - m = m->m_next; - } - - for (;m && len; m = m->m_next) { - if (m->m_len == 0) - continue; - w = (u_int16_t *)(mtod(m, caddr_t) + off); - if (mlen == -1) { - /* - * The first byte of this mbuf is the continuation - * of a word spanning between this mbuf and the - * last mbuf. - * - * s_util.c[0] is already saved when scanning previous - * mbuf. - */ - s_util.c[1] = *(u_int8_t *)w; - sum += s_util.s; - w = (u_int16_t *)((u_int8_t *)w + 1); - mlen = m->m_len - off - 1; - len--; - } else - mlen = m->m_len - off; - off = 0; - if (len < mlen) - mlen = len; - len -= mlen; - /* - * Force to even boundary. - */ - if ((1 & (long) w) && (mlen > 0)) { - REDUCE; - sum <<= 8; - s_util.c[0] = *(u_int8_t *)w; - w = (u_int16_t *)((int8_t *)w + 1); - mlen--; - byte_swapped = 1; - } - /* - * Unroll the loop to make overhead from - * branches &c small. - */ - while ((mlen -= 32) >= 0) { - sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; - sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7]; - sum += w[8]; sum += w[9]; sum += w[10]; sum += w[11]; - sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15]; - w += 16; - } - mlen += 32; - while ((mlen -= 8) >= 0) { - sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; - w += 4; - } - mlen += 8; - if (mlen == 0 && byte_swapped == 0) - continue; - REDUCE; - while ((mlen -= 2) >= 0) { - sum += *w++; - } - if (byte_swapped) { - REDUCE; - sum <<= 8; - byte_swapped = 0; - if (mlen == -1) { - s_util.c[1] = *(u_int8_t *)w; - sum += s_util.s; - mlen = 0; - } else - mlen = -1; - } else if (mlen == -1) - s_util.c[0] = *(u_int8_t *)w; - } - if (len) - printf("cksum4: out of data\n"); - if (mlen == -1) { - /* The last mbuf has odd # of bytes. Follow the - standard (the odd byte may be shifted left by 8 bits - or not as determined by endian-ness of the machine) */ - s_util.c[1] = 0; - sum += s_util.s; - } + psum = in_cksum_skip(m, len + off, off); + psum = ~psum & 0xffff; + sum += psum; REDUCE; return (~sum & 0xffff); } |
