[src/trunk]: src/sys/net/npf Add nbuf_advfetch() and simplify some code sligh...

[rmind <rmind%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a5ce42be0e77
branches:  trunk
changeset: 757818:a5ce42be0e77
user:      rmind <rmind%NetBSD.org@localhost>
date:      Sat Sep 25 00:25:31 2010 +0000

description:
Add nbuf_advfetch() and simplify some code slightly.

diffstat:

 sys/net/npf/npf.h          |   3 +-
 sys/net/npf/npf_alg_icmp.c |  28 +++++++----------------
 sys/net/npf/npf_inet.c     |  54 ++++++++++++++++-----------------------------
 sys/net/npf/npf_instr.c    |   9 ++-----
 sys/net/npf/npf_mbuf.c     |  19 ++++++++++++++-
 sys/net/npf/npf_sendpkt.c  |  16 ++++---------
 6 files changed, 55 insertions(+), 74 deletions(-)

diffs (truncated from 344 to 300 lines):

diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf.h
--- a/sys/net/npf/npf.h Fri Sep 24 22:51:50 2010 +0000
+++ b/sys/net/npf/npf.h Sat Sep 25 00:25:31 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf.h,v 1.2 2010/09/16 04:53:27 rmind Exp $    */
+/*     $NetBSD: npf.h,v 1.3 2010/09/25 00:25:31 rmind Exp $    */
 
 /*-
  * Copyright (c) 2009-2010 The NetBSD Foundation, Inc.
@@ -110,6 +110,7 @@
 /* Network buffer interface. */
 void *         nbuf_dataptr(void *);
 void *         nbuf_advance(nbuf_t **, void *, u_int);
+int            nbuf_advfetch(nbuf_t **, void **, u_int, size_t, void *);
 int            nbuf_fetch_datum(nbuf_t *, void *, size_t, void *);
 int            nbuf_store_datum(nbuf_t *, void *, size_t, void *);
 
diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf_alg_icmp.c
--- a/sys/net/npf/npf_alg_icmp.c        Fri Sep 24 22:51:50 2010 +0000
+++ b/sys/net/npf/npf_alg_icmp.c        Sat Sep 25 00:25:31 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf_alg_icmp.c,v 1.2 2010/09/16 04:53:27 rmind Exp $   */
+/*     $NetBSD: npf_alg_icmp.c,v 1.3 2010/09/25 00:25:31 rmind Exp $   */
 
 /*-
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
 
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npf_alg_icmp.c,v 1.2 2010/09/16 04:53:27 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npf_alg_icmp.c,v 1.3 2010/09/25 00:25:31 rmind Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -119,6 +119,8 @@
 {
        const int proto = npc->npc_proto;
        void *n_ptr = nbuf_dataptr(nbuf);
+       u_int offby;
+       uint8_t ttl;
 
        /* Handle TCP/UDP traceroute - check for port range. */
        if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) {
@@ -131,17 +133,11 @@
        }
 
        /* Check for low TTL. */
-       const u_int offby = offsetof(struct ip, ip_ttl);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL) {
+       offby = offsetof(struct ip, ip_ttl);
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), &ttl))
                return false;
-       }
-       uint8_t ttl;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &ttl)) {
+       if (ttl > TR_MAX_TTL)
                return false;
-       }
-       if (ttl > TR_MAX_TTL) {
-               return false;
-       }
 
        /* Associate ALG with translation entry. */
        npf_nat_t *nt = ntptr;
@@ -194,10 +190,7 @@
        case ICMP_IREQREPLY:
                /* Should contain ICMP query ID. */
                offby = offsetof(struct icmp, icmp_id);
-               if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL) {
-                       return false;
-               }
-               if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint16_t),
+               if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint16_t),
                    &npc->npc_icmp_id)) {
                        return false;
                }
@@ -286,10 +279,7 @@
 
        /* Advance to ICMP checksum and fetch it. */
        offby = npc->npc_hlen + offsetof(struct icmp, icmp_cksum);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL) {
-               return false;
-       }
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint16_t), &cksum)) {
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint16_t), &cksum)) {
                return false;
        }
 
diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf_inet.c
--- a/sys/net/npf/npf_inet.c    Fri Sep 24 22:51:50 2010 +0000
+++ b/sys/net/npf/npf_inet.c    Sat Sep 25 00:25:31 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf_inet.c,v 1.2 2010/09/16 04:53:27 rmind Exp $       */
+/*     $NetBSD: npf_inet.c,v 1.3 2010/09/25 00:25:31 rmind Exp $       */
 
 /*-
  * Copyright (c) 2009-2010 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
 
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npf_inet.c,v 1.2 2010/09/16 04:53:27 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npf_inet.c,v 1.3 2010/09/25 00:25:31 rmind Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -106,28 +106,23 @@
        hlen = (val8 & 0xf) << 2;
        if (hlen < sizeof(struct ip))
                return false;
-       offby = offsetof(struct ip, ip_off);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
 
        /* IPv4 header: check fragment offset. */
-       error = nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &val8);
+       offby = offsetof(struct ip, ip_off);
+       error = nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), &val8);
        if (error || (val8 & ~htons(IP_DF | IP_RF)))
                return false;
 
        /* Get and match protocol. */
        KASSERT(offsetof(struct ip, ip_p) > offby);
        offby = offsetof(struct ip, ip_p) - offby;
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &val8))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), &val8))
                return false;
 
        /* IP checksum. */
        offby = offsetof(struct ip, ip_sum) - offsetof(struct ip, ip_p);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint16_t), &npc->npc_ipsum))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby,
+           sizeof(uint16_t), &npc->npc_ipsum))
                return false;
 
        /* Cache: IPv4, protocol, header length. */
@@ -145,20 +140,17 @@
 bool
 npf_fetch_ip4addrs(npf_cache_t *npc, nbuf_t *nbuf, void *n_ptr)
 {
+       in_addr_t *src = &npc->npc_srcip, *dst = &npc->npc_dstip;
        u_int offby;
 
        /* Source address. */
        offby = offsetof(struct ip, ip_src);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(in_addr_t), &npc->npc_srcip))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(in_addr_t), src))
                return false;
 
        /* Destination address. */
        offby = offsetof(struct ip, ip_dst) - offby;
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(in_addr_t), &npc->npc_dstip))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(in_addr_t), dst))
                return false;
 
        /* Both addresses are cached. */
@@ -216,28 +208,23 @@
 bool
 npf_fetch_icmp(npf_cache_t *npc, nbuf_t *nbuf, void *n_ptr)
 {
+       uint8_t *type = &npc->npc_icmp_type, *code = &npc->npc_icmp_code;
        u_int offby;
-       uint8_t type;
 
        KASSERT(npf_iscached(npc, NPC_IP46));
 
        /* ICMP type. */
        offby = npc->npc_hlen;
        CTASSERT(offsetof(struct icmp, icmp_type) == 0);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &type))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), type))
                return false;
 
        /* ICMP code. */
        offby = offsetof(struct icmp, icmp_code);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
-               return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &npc->npc_icmp_code))
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), code))
                return false;
 
        /* Mark as cached. */
-       npc->npc_icmp_type = type;
        npc->npc_info |= NPC_ICMP;
        return true;
 }
@@ -248,14 +235,12 @@
 bool
 npf_fetch_tcpfl(npf_cache_t *npc, nbuf_t *nbuf, void *n_ptr)
 {
-       u_int offby;
+       const u_int offby = npc->npc_hlen + offsetof(struct tcphdr, th_flags);
+       uint8_t *tcpfl = &npc->npc_tcp_flags;
 
-       /* Get TCP flags. */
-       offby = npc->npc_hlen + offsetof(struct tcphdr, th_flags);
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL)
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint8_t), tcpfl)) {
                return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint8_t), &npc->npc_tcp_flags))
-               return false;
+       }
        return true;
 }
 
@@ -346,10 +331,9 @@
                return false;
 
        /* Advance and update TCP/UDP checksum. */
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, toff)) == NULL)
+       if (nbuf_advfetch(&nbuf, &n_ptr, toff, sizeof(uint16_t), &cksum)) {
                return false;
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint16_t), &cksum))
-               return false;
+       }
        if (__predict_true(cksum || proto == IPPROTO_TCP)) {
                cksum = npf_fixup32_cksum(cksum, oaddr, naddr);
                cksum = npf_fixup16_cksum(cksum, oport, port);
diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf_instr.c
--- a/sys/net/npf/npf_instr.c   Fri Sep 24 22:51:50 2010 +0000
+++ b/sys/net/npf/npf_instr.c   Sat Sep 25 00:25:31 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf_instr.c,v 1.2 2010/09/16 04:53:27 rmind Exp $      */
+/*     $NetBSD: npf_instr.c,v 1.3 2010/09/25 00:25:31 rmind Exp $      */
 
 /*-
  * Copyright (c) 2009-2010 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
 
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npf_instr.c,v 1.2 2010/09/16 04:53:27 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npf_instr.c,v 1.3 2010/09/25 00:25:31 rmind Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -71,10 +71,7 @@
        /* Ethernet header: check EtherType. */
        offby = offsetof(struct ether_header, ether_type);
 again:
-       if ((n_ptr = nbuf_advance(&nbuf, n_ptr, offby)) == NULL) {
-               return -1;
-       }
-       if (nbuf_fetch_datum(nbuf, n_ptr, sizeof(uint16_t), &val16)) {
+       if (nbuf_advfetch(&nbuf, &n_ptr, offby, sizeof(uint16_t), &val16)) {
                return -1;
        }
        val16 = ntohs(val16);
diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf_mbuf.c
--- a/sys/net/npf/npf_mbuf.c    Fri Sep 24 22:51:50 2010 +0000
+++ b/sys/net/npf/npf_mbuf.c    Sat Sep 25 00:25:31 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf_mbuf.c,v 1.2 2010/09/16 04:53:27 rmind Exp $       */
+/*     $NetBSD: npf_mbuf.c,v 1.3 2010/09/25 00:25:31 rmind Exp $       */
 
 /*-
  * Copyright (c) 2009-2010 The NetBSD Foundation, Inc.
@@ -38,7 +38,7 @@
 
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npf_mbuf.c,v 1.2 2010/09/16 04:53:27 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npf_mbuf.c,v 1.3 2010/09/25 00:25:31 rmind Exp $");
 #endif
 
 #include <sys/param.h>
@@ -188,6 +188,21 @@
 }
 
 /*
+ * nbuf_advfetch: advance and fetch the datum.
+ * WARNING: Values of nbuf and n_ptr are undefined on error.
+ */
+int
+nbuf_advfetch(nbuf_t **nbuf, void **n_ptr, u_int n, size_t len, void *buf)
+{
+
+       *n_ptr = nbuf_advance(nbuf, *n_ptr, n);
+       if (__predict_false(*n_ptr == NULL)) {
+               return EINVAL;
+       }
+       return nbuf_fetch_datum(*nbuf, n_ptr, len, buf);
+}
+
+/*
  * nbuf_add_tag: add a tag to specified network buffer.
  *
  * => Returns 0 on success, or errno on failure.
diff -r 6f9c716d8d3a -r a5ce42be0e77 sys/net/npf/npf_sendpkt.c