[src/trunk]: src/usr.sbin/npf/npfctl - better printing of type/code flags/mask

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

details:   https://anonhg.NetBSD.org/src/rev/fb5aa9fb3a5a
branches:  trunk
changeset: 777951:fb5aa9fb3a5a
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Mar 10 22:55:28 2012 +0000

description:
- better printing of type/code flags/mask
- pass the instruction start pointer, instead of subtracting 1 to account for it

diffstat:

 usr.sbin/npf/npfctl/npf_disassemble.c |  31 ++++++++++++++++++++++---------
 1 files changed, 22 insertions(+), 9 deletions(-)

diffs (91 lines):

diff -r 602d947b1bcc -r fb5aa9fb3a5a usr.sbin/npf/npfctl/npf_disassemble.c
--- a/usr.sbin/npf/npfctl/npf_disassemble.c     Sat Mar 10 22:22:38 2012 +0000
+++ b/usr.sbin/npf/npfctl/npf_disassemble.c     Sat Mar 10 22:55:28 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npf_disassemble.c,v 1.1 2012/03/10 22:21:50 christos Exp $     */
+/*     $NetBSD: npf_disassemble.c,v 1.2 2012/03/10 22:55:28 christos Exp $     */
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: npf_disassemble.c,v 1.1 2012/03/10 22:21:50 christos Exp $");
+__RCSID("$NetBSD: npf_disassemble.c,v 1.2 2012/03/10 22:55:28 christos Exp $");
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -86,8 +86,8 @@
 
 static const char *
 npfctl_ncode_operand(char *buf, size_t bufsiz, uint8_t op, const uint32_t *st,
-    const uint32_t **pcv, size_t *lenv, const uint32_t ***t, size_t *l,
-    size_t *m)
+    const uint32_t *ipc, const uint32_t **pcv, size_t *lenv,
+    const uint32_t ***t, size_t *l, size_t *m)
 {
        const uint32_t *pc = *pcv;
        size_t len = *lenv;
@@ -130,7 +130,7 @@
 
        case NPF_OPERAND_REL_ADDRESS:
                snprintf(buf, bufsiz, "+%zu",
-                   npfctl_ncode_add_target(pc + *pc - 1, t, l, m));
+                   npfctl_ncode_add_target(ipc + *pc, t, l, m));
                ADVANCE(1, NULL);
                break;
 
@@ -177,12 +177,24 @@
                break;
 
        case NPF_OPERAND_ICMP4_TYPE_CODE:
-               snprintf(buf, bufsiz, "icmp=0x%x", *pc);
+               if (*pc & ~0xffff) {
+                       warnx("Bad icmp/type operand 0x%x at offset %td",
+                           *pc, pc - st);
+                       return NULL;
+               }
+               snprintf(buf, bufsiz, "type=%d, code=%d", *pc >> 8,
+                   *pc & 0xff);
                ADVANCE(1, NULL);
                break;
 
        case NPF_OPERAND_TCP_FLAGS_MASK:
-               snprintf(buf, bufsiz, "flmask=0x%x", *pc);
+               if (*pc & ~0xffff) {
+                       warnx("Bad flags/mask operand 0x%x at offset %td",
+                           *pc, pc - st);
+                       return NULL;
+               }
+               snprintf(buf, bufsiz, "type=%d, code=%d", *pc >> 8,
+                   *pc & 0xff);
                ADVANCE(1, NULL);
                break;
 
@@ -203,7 +215,7 @@
 int
 npfctl_ncode_disassemble(FILE *fp, const void *v, size_t len)
 {
-       const uint32_t *pc = v;
+       const uint32_t *ipc, *pc = v;
        const uint32_t *st = v;
        const struct npf_instruction *ni;
        char buf[256];
@@ -225,6 +237,7 @@
                            pc - st);
                        return -1;
                }
+               ipc = pc;
                target = npfctl_ncode_get_target(pc, targ, tlen);
                if (target != (size_t)~0)
                        printf("%zu:", target);
@@ -235,7 +248,7 @@
                        if (ni->op[i] == NPF_OPERAND_NONE)
                                break;
                        op = npfctl_ncode_operand(buf, sizeof(buf), ni->op[i],
-                           st, &pc, &len, &targ, &tlen, &mlen);
+                           st, ipc, &pc, &len, &targ, &tlen, &mlen);
                        if (op == NULL)
                                return -1;
                        fprintf(fp, "%s%s", i == 0 ? " " : ", ", op);