*/
#ifndef lint
static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/libpcap/optimize.c,v 1.83 2004-11-14 03:10:33 guy Exp $ (LBL)";
+ "@(#) $Header: /tcpdump/master/libpcap/optimize.c,v 1.91 2008-01-02 04:16:46 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include <stdio.h>
#include <stdlib.h>
#include <memory.h>
+#include <string.h>
#include <errno.h>
extern int dflag;
#endif
+#if defined(MSDOS) && !defined(__DJGPP__)
+extern int _w32_ffs (int mask);
+#define ffs _w32_ffs
+#endif
+
+#if defined(WIN32) && defined (_MSC_VER)
+int ffs(int mask);
+#endif
+
/*
* Represents a deleted instruction.
*/
* Compute the sets of registers used, defined, and killed by 'b'.
*
* "Used" means that a statement in 'b' uses the register before any
- * statement in 'b' defines it.
+ * statement in 'b' defines it, i.e. it uses the value left in
+ * that register by a predecessor block of this block.
* "Defined" means that a statement in 'b' defines it.
* "Killed" means that a statement in 'b' defines it before any
- * statement in 'b' uses it.
+ * statement in 'b' uses it, i.e. it kills the value left in that
+ * register by a predecessor block of this block.
*/
static void
compute_local_ud(b)
struct stmt *s;
int v0, v1;
{
- bpf_int32 a, b;
+ bpf_u_int32 a, b;
a = vmap[v0].const_val;
b = vmap[v1].const_val;
if (b->s.k == 0xffffffff)
JF(b) = JT(b);
}
+ /*
+ * If we're comparing against the index register, and the index
+ * register is a known constant, we can just compare against that
+ * constant.
+ */
+ val = b->val[X_ATOM];
+ if (vmap[val].is_const && BPF_SRC(b->s.code) == BPF_X) {
+ bpf_int32 v = vmap[val].const_val;
+ b->s.code &= ~BPF_X;
+ b->s.k = v;
+ }
/*
* If the accumulator is a known constant, we can compute the
* comparison result.
{
struct block *p;
int i, j;
- int done;
+ int done1; /* don't shadow global */
top:
- done = 1;
+ done1 = 1;
for (i = 0; i < n_blocks; ++i)
blocks[i]->link = 0;
if (JT(p) == 0)
continue;
if (JT(p)->link) {
- done = 0;
+ done1 = 0;
JT(p) = JT(p)->link;
}
if (JF(p)->link) {
- done = 0;
+ done1 = 0;
JF(p) = JF(p)->link;
}
}
- if (!done)
+ if (!done1)
goto top;
}
*/
unMarkAll();
n = count_blocks(root);
- blocks = (struct block **)malloc(n * sizeof(*blocks));
+ blocks = (struct block **)calloc(n, sizeof(*blocks));
if (blocks == NULL)
bpf_error("malloc");
unMarkAll();
number_blks_r(root);
n_edges = 2 * n_blocks;
- edges = (struct edge **)malloc(n_edges * sizeof(*edges));
+ edges = (struct edge **)calloc(n_edges, sizeof(*edges));
if (edges == NULL)
bpf_error("malloc");
/*
* The number of levels is bounded by the number of nodes.
*/
- levels = (struct block **)malloc(n_blocks * sizeof(*levels));
+ levels = (struct block **)calloc(n_blocks, sizeof(*levels));
if (levels == NULL)
bpf_error("malloc");
* we'll need.
*/
maxval = 3 * max_stmts;
- vmap = (struct vmapinfo *)malloc(maxval * sizeof(*vmap));
- vnode_base = (struct valnode *)malloc(maxval * sizeof(*vnode_base));
+ vmap = (struct vmapinfo *)calloc(maxval, sizeof(*vmap));
+ vnode_base = (struct valnode *)calloc(maxval, sizeof(*vnode_base));
if (vmap == NULL || vnode_base == NULL)
bpf_error("malloc");
}
{
int i;
int jt, jf;
- char *ljerr = "%s for block-local relative jump: off=%d";
+ const char *ljerr = "%s for block-local relative jump: off=%d";
#if 0
printf("code=%x off=%d %x %x\n", src->s.code,
/*
* Convert flowgraph intermediate representation to the
* BPF array representation. Set *lenp to the number of instructions.
+ *
+ * This routine does *NOT* leak the memory pointed to by fp. It *must
+ * not* do free(fp) before returning fp; doing so would make no sense,
+ * as the BPF array pointed to by the return value of icode_to_fcode()
+ * must be valid - it's being returned for use in a bpf_program structure.
+ *
+ * If it appears that icode_to_fcode() is leaking, the problem is that
+ * the program using pcap_compile() is failing to free the memory in
+ * the BPF program when it's done - the leak is in the program, not in
+ * the routine that happens to be allocating the memory. (By analogy, if
+ * a program calls fopen() without ever calling fclose() on the FILE *,
+ * it will leak the FILE structure; the leak is not in fopen(), it's in
+ * the program.) Change the program to use pcap_freecode() when it's
+ * done with the filter program. See the pcap man page.
*/
struct bpf_insn *
icode_to_fcode(root, lenp)
{
size_t prog_size;
+ /*
+ * Validate the program.
+ */
+ if (!bpf_validate(fp->bf_insns, fp->bf_len)) {
+ snprintf(p->errbuf, sizeof(p->errbuf),
+ "BPF program is not valid");
+ return (-1);
+ }
+
/*
* Free up any already installed program.
*/
projects / libpcap / blobdiff