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/*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 2001 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <string.h>
#include <ftypes-int.h>
#include <epan/ipv4.h>
#include <epan/addr_and_mask.h>
#include <epan/addr_resolv.h>
static void
set_uinteger(fvalue_t *fv, guint32 value)
{
fv->value.ipv4.addr = g_ntohl(value);
fv->value.ipv4.nmask = ip_get_subnet_mask(32);
}
static guint32
value_get(fvalue_t *fv)
{
return g_htonl(fv->value.ipv4.addr);
}
static gboolean
val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_, gchar **err_msg)
{
guint32 addr;
unsigned int nmask_bits;
const char *slash, *net_str;
const char *addr_str;
char *addr_str_to_free = NULL;
fvalue_t *nmask_fvalue;
/* Look for CIDR: Is there a single slash in the string? */
slash = strchr(s, '/');
if (slash) {
/* Make a copy of the string up to but not including the
* slash; that's the address portion. */
addr_str_to_free = wmem_strndup(NULL, s, slash - s);
addr_str = addr_str_to_free;
}
else {
addr_str = s;
}
if (!get_host_ipaddr(addr_str, &addr)) {
if (err_msg != NULL) {
*err_msg = g_strdup_printf("\"%s\" is not a valid hostname or IPv4 address.",
addr_str);
}
if (addr_str_to_free)
wmem_free(NULL, addr_str_to_free);
return FALSE;
}
if (addr_str_to_free)
wmem_free(NULL, addr_str_to_free);
fv->value.ipv4.addr = g_ntohl(addr);
/* If CIDR, get netmask bits. */
if (slash) {
/* Skip past the slash */
net_str = slash + 1;
/* XXX - this is inefficient */
nmask_fvalue = fvalue_from_unparsed(FT_UINT32, net_str, FALSE, err_msg);
if (!nmask_fvalue) {
return FALSE;
}
nmask_bits = fvalue_get_uinteger(nmask_fvalue);
FVALUE_FREE(nmask_fvalue);
if (nmask_bits > 32) {
if (err_msg != NULL) {
*err_msg = g_strdup_printf("Netmask bits in a CIDR IPv4 address should be <= 32, not %u",
nmask_bits);
}
return FALSE;
}
fv->value.ipv4.nmask = ip_get_subnet_mask(nmask_bits);
}
else {
/* Not CIDR; mask covers entire address. */
fv->value.ipv4.nmask = ip_get_subnet_mask(32);
}
return TRUE;
}
static char *
val_to_repr(wmem_allocator_t *scope, const fvalue_t *fv, ftrepr_t rtype _U_, int field_display _U_)
{
guint32 ipv4_net_order = g_htonl(fv->value.ipv4.addr);
return ip_to_str(scope, (guint8*)&ipv4_net_order);
}
/* Compares two ipv4_addr_and_masks, taking into account the less restrictive of the
* two netmasks, applying that netmask to both addrs.
*
* So, for example, w.x.y.z/32 eq w.x.y.0/24 is TRUE.
*/
static int
cmp_order(const fvalue_t *fv_a, const fvalue_t *fv_b)
{
guint32 addr_a, addr_b, nmask;
nmask = MIN(fv_a->value.ipv4.nmask, fv_b->value.ipv4.nmask);
addr_a = fv_a->value.ipv4.addr & nmask;
addr_b = fv_b->value.ipv4.addr & nmask;
if (addr_a == addr_b)
return 0;
return addr_a < addr_b ? -1 : 1;
}
static gboolean
cmp_bitwise_and(const fvalue_t *fv_a, const fvalue_t *fv_b)
{
guint32 addr_a;
guint32 addr_b;
addr_a = fv_a->value.ipv4.addr & fv_a->value.ipv4.nmask;
addr_b = fv_b->value.ipv4.addr & fv_b->value.ipv4.nmask;
return ((addr_a & addr_b) != 0);
}
static void
slice(fvalue_t *fv, GByteArray *bytes, guint offset, guint length)
{
guint8* data;
guint32 addr = g_htonl(fv->value.ipv4.addr);
data = ((guint8*)&addr)+offset;
g_byte_array_append(bytes, data, length);
}
void
ftype_register_ipv4(void)
{
static ftype_t ipv4_type = {
FT_IPv4, /* ftype */
"FT_IPv4", /* name */
"IPv4 address", /* pretty_name */
4, /* wire_size */
NULL, /* new_value */
NULL, /* free_value */
val_from_unparsed, /* val_from_unparsed */
NULL, /* val_from_string */
val_to_repr, /* val_to_string_repr */
{ .set_value_uinteger = set_uinteger }, /* union set_value */
{ .get_value_uinteger = value_get }, /* union get_value */
cmp_order,
cmp_bitwise_and,
NULL, /* cmp_contains */
NULL, /* cmp_matches */
NULL,
slice,
};
ftype_register(FT_IPv4, &ipv4_type);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/
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