nat: Allow to use the prefix lookup to rewrite numbers

* Increase the rewritten rule to five digits (this is the easiest
  for the unit test). This will add another 40kb to the runtime size.

* Create a unit test that tests adding and removing the prefix rules.

* Use the regexp match to replace from one package
This commit is contained in:
Holger Hans Peter Freyther 2013-06-25 11:44:01 +02:00 committed by Holger Hans Peter Freyther
parent 85d3b34ed2
commit ddf191eafc
10 changed files with 203 additions and 9 deletions

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@ -45,6 +45,7 @@ struct nat_sccp_connection;
struct bsc_nat_parsed;
struct bsc_nat;
struct bsc_nat_ussd_con;
struct nat_rewrite_rule;
enum {
NAT_CON_TYPE_NONE,
@ -308,6 +309,10 @@ struct bsc_nat {
char *sms_num_rewr_name;
struct llist_head sms_num_rewr;
/* more rewriting */
char *num_rewr_trie_name;
struct nat_rewrite *num_rewr_trie;
/* USSD messages we want to match */
char *ussd_lst_name;
char *ussd_query;
@ -452,6 +457,7 @@ struct bsc_nat_num_rewr_entry {
regex_t num_reg;
char *replace;
uint8_t is_prefix_lookup;
};
void bsc_nat_num_rewr_entry_adapt(void *ctx, struct llist_head *head, const struct osmo_config_list *);

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@ -22,13 +22,15 @@
#include <osmocom/core/linuxrbtree.h>
struct vty;
struct nat_rewrite_rule {
/* For digits 0-9 and + */
struct nat_rewrite_rule *rules[11];
char empty;
char prefix[14];
char rewrite[4];
char rewrite[6];
};
struct nat_rewrite {
@ -40,5 +42,6 @@ struct nat_rewrite {
struct nat_rewrite *nat_rewrite_parse(void *ctx, const char *filename);
struct nat_rewrite_rule *nat_rewrite_lookup(struct nat_rewrite *, const char *prefix);
void nat_rewrite_dump(struct nat_rewrite *rewr);
void nat_rewrite_dump_vty(struct vty *vty, struct nat_rewrite *rewr);
#endif

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@ -27,6 +27,7 @@
#include <openbsc/gsm_data.h>
#include <openbsc/debug.h>
#include <openbsc/ipaccess.h>
#include <openbsc/nat_rewrite_trie.h>
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/talloc.h>
@ -37,9 +38,30 @@
#include <osmocom/sccp/sccp.h>
static char *trie_lookup(struct nat_rewrite *trie, const char *number,
regoff_t off, void *ctx)
{
struct nat_rewrite_rule *rule;
if (!trie) {
LOGP(DNAT, LOGL_ERROR,
"Asked to do a table lookup but no table.\n");
return NULL;
}
rule = nat_rewrite_lookup(trie, number);
if (!rule) {
LOGP(DNAT, LOGL_DEBUG,
"Couldn't find a prefix rule for %s\n", number);
return NULL;
}
return talloc_asprintf(ctx, "%s%s", rule->rewrite, &number[off]);
}
static char *match_and_rewrite_number(void *ctx, const char *number,
const char *imsi,
struct llist_head *list)
const char *imsi, struct llist_head *list,
struct nat_rewrite *trie)
{
struct bsc_nat_num_rewr_entry *entry;
char *new_number = NULL;
@ -53,11 +75,17 @@ static char *match_and_rewrite_number(void *ctx, const char *number,
continue;
/* this regexp matches... */
if (regexec(&entry->num_reg, number, 2, matches, 0) == 0 &&
matches[1].rm_eo != -1)
new_number = talloc_asprintf(ctx, "%s%s",
if (regexec(&entry->num_reg, number, 2, matches, 0) == 0
&& matches[1].rm_eo != -1) {
if (entry->is_prefix_lookup)
new_number = trie_lookup(trie, number,
matches[1].rm_so, ctx);
else
new_number = talloc_asprintf(ctx, "%s%s",
entry->replace,
&number[matches[1].rm_so]);
}
if (new_number)
break;
}
@ -86,7 +114,7 @@ static char *rewrite_isdn_number(struct bsc_nat *nat, void *ctx, const char *ims
}
return match_and_rewrite_number(ctx, number,
imsi, &nat->num_rewr);
imsi, &nat->num_rewr, nat->num_rewr_trie);
}
@ -261,7 +289,7 @@ static char *sms_new_dest_nr(struct bsc_nat *nat, void *ctx,
const char *imsi, const char *dest_nr)
{
return match_and_rewrite_number(ctx, dest_nr, imsi,
&nat->sms_num_rewr);
&nat->sms_num_rewr, NULL);
}
/**
@ -600,6 +628,9 @@ void bsc_nat_num_rewr_entry_adapt(void *ctx, struct llist_head *head,
continue;
}
if (strcmp("prefix_lookup", entry->replace) == 0)
entry->is_prefix_lookup = 1;
/* we will now build a regexp string */
if (cfg_entry->mcc[0] == '^') {
regexp = talloc_strdup(entry, cfg_entry->mcc);

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@ -21,6 +21,7 @@
#include <openbsc/nat_rewrite_trie.h>
#include <openbsc/debug.h>
#include <openbsc/vty.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/utils.h>
@ -238,3 +239,21 @@ void nat_rewrite_dump(struct nat_rewrite *rewrite)
{
nat_rewrite_dump_rec(&rewrite->rule);
}
static void nat_rewrite_dump_rec_vty(struct vty *vty, struct nat_rewrite_rule *rule)
{
int i;
if (!rule->empty)
vty_out(vty, "%s,%s%s", rule->prefix, rule->rewrite, VTY_NEWLINE);
for (i = 0; i < ARRAY_SIZE(rule->rules); ++i) {
if (!rule->rules[i])
continue;
nat_rewrite_dump_rec_vty(vty, rule->rules[i]);
}
}
void nat_rewrite_dump_vty(struct vty *vty, struct nat_rewrite *rewrite)
{
nat_rewrite_dump_rec_vty(vty, &rewrite->rule);
}

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@ -26,6 +26,7 @@
#include <openbsc/gsm_04_08.h>
#include <openbsc/mgcp.h>
#include <openbsc/vty.h>
#include <openbsc/nat_rewrite_trie.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/rate_ctr.h>
@ -138,6 +139,9 @@ static int config_write_nat(struct vty *vty)
if (_nat->sms_num_rewr_name)
vty_out(vty, " sms-number-rewrite %s%s",
_nat->sms_num_rewr_name, VTY_NEWLINE);
if (_nat->num_rewr_trie_name)
vty_out(vty, " prefix-tree %s%s",
_nat->num_rewr_trie_name, VTY_NEWLINE);
llist_for_each_entry(lst, &_nat->access_lists, list)
write_acc_lst(vty, lst);
@ -633,6 +637,59 @@ DEFUN(cfg_nat_no_sms_number_rewrite,
return CMD_SUCCESS;
}
DEFUN(cfg_nat_prefix_trie,
cfg_nat_prefix_trie_cmd,
"prefix-tree FILENAME",
"Prefix tree for number rewriting\n" "File to load\n")
{
/* give up the old data */
talloc_free(_nat->num_rewr_trie);
_nat->num_rewr_trie = NULL;
/* replace the file name */
bsc_replace_string(_nat, &_nat->num_rewr_trie_name, argv[0]);
if (!_nat->num_rewr_trie_name) {
vty_out(vty, "%% prefix-tree no filename is present.%s", VTY_NEWLINE);
return CMD_WARNING;
}
_nat->num_rewr_trie = nat_rewrite_parse(_nat, _nat->num_rewr_trie_name);
if (!_nat->num_rewr_trie) {
vty_out(vty, "%% prefix-tree parsing has failed.%s", VTY_NEWLINE);
return CMD_WARNING;
}
vty_out(vty, "%% prefix-tree loaded %zu rules.%s",
_nat->num_rewr_trie->prefixes, VTY_NEWLINE);
return CMD_SUCCESS;
}
DEFUN(cfg_nat_no_prefix_trie, cfg_nat_no_prefix_trie_cmd,
"no prefix-tree",
NO_STR "Prefix tree for number rewriting\n")
{
talloc_free(_nat->num_rewr_trie);
_nat->num_rewr_trie = NULL;
talloc_free(_nat->num_rewr_trie_name);
_nat->num_rewr_trie_name = NULL;
return CMD_SUCCESS;
}
DEFUN(show_prefix_tree, show_prefix_tree_cmd,
"show prefix-tree",
SHOW_STR "Prefix tree for number rewriting\n")
{
if (!_nat->num_rewr_trie) {
vty_out(vty, "%% there is now prefix tree loaded.%s",
VTY_NEWLINE);
return CMD_WARNING;
}
nat_rewrite_dump_vty(vty, _nat->num_rewr_trie);
return CMD_SUCCESS;
}
DEFUN(cfg_nat_ussd_lst_name,
cfg_nat_ussd_lst_name_cmd,
"ussd-list-name NAME",
@ -1089,6 +1146,7 @@ int bsc_nat_vty_init(struct bsc_nat *nat)
install_element_ve(&show_bsc_mgcp_cmd);
install_element_ve(&show_acc_lst_cmd);
install_element_ve(&show_bar_lst_cmd);
install_element_ve(&show_prefix_tree_cmd);
install_element(ENABLE_NODE, &set_last_endp_cmd);
install_element(ENABLE_NODE, &block_new_conn_cmd);
@ -1131,6 +1189,8 @@ int bsc_nat_vty_init(struct bsc_nat *nat)
install_element(NAT_NODE, &cfg_nat_no_sms_clear_tpsrr_cmd);
install_element(NAT_NODE, &cfg_nat_sms_number_rewrite_cmd);
install_element(NAT_NODE, &cfg_nat_no_sms_number_rewrite_cmd);
install_element(NAT_NODE, &cfg_nat_prefix_trie_cmd);
install_element(NAT_NODE, &cfg_nat_no_prefix_trie_cmd);
install_element(NAT_NODE, &cfg_nat_pgroup_cmd);
install_element(NAT_NODE, &cfg_nat_no_pgroup_cmd);

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@ -2,7 +2,7 @@ AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include
AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOSCCP_CFLAGS) $(LIBOSMOABIS_CFLAGS) $(COVERAGE_CFLAGS)
AM_LDFLAGS = $(COVERAGE_LDFLAGS)
EXTRA_DIST = bsc_nat_test.ok bsc_data.c barr.cfg barr_dup.cfg
EXTRA_DIST = bsc_nat_test.ok bsc_data.c barr.cfg barr_dup.cfg prefixes.csv
noinst_PROGRAMS = bsc_nat_test
@ -12,6 +12,7 @@ bsc_nat_test_SOURCES = bsc_nat_test.c \
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_utils.c \
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_filter.c \
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_rewrite.c \
$(top_srcdir)/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c \
$(top_srcdir)/src/osmo-bsc_nat/bsc_mgcp_utils.c
bsc_nat_test_LDADD = $(top_builddir)/src/libbsc/libbsc.a \
$(top_srcdir)/src/libctrl/libctrl.a \

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@ -26,6 +26,7 @@
#include <openbsc/gsm_data.h>
#include <openbsc/bsc_nat.h>
#include <openbsc/bsc_nat_sccp.h>
#include <openbsc/nat_rewrite_trie.h>
#include <osmocom/core/application.h>
#include <osmocom/core/backtrace.h>
@ -1041,6 +1042,55 @@ static void test_setup_rewrite()
msgb_free(out);
}
static void test_setup_rewrite_prefix(void)
{
struct msgb *msg = msgb_alloc(4096, "test_dt_filter");
struct msgb *out;
struct bsc_nat_parsed *parsed;
const char *imsi = "27408000001234";
struct bsc_nat *nat = bsc_nat_alloc();
/* a fake list */
struct osmo_config_list entries;
struct osmo_config_entry entry;
INIT_LLIST_HEAD(&entries.entry);
entry.mcc = "274";
entry.mnc = "08";
entry.option = "^0([1-9])";
entry.text = "prefix_lookup";
llist_add_tail(&entry.list, &entries.entry);
bsc_nat_num_rewr_entry_adapt(nat, &nat->num_rewr, &entries);
nat->num_rewr_trie = nat_rewrite_parse(nat, "prefixes.csv");
msgb_reset(msg);
copy_to_msg(msg, cc_setup_national, ARRAY_SIZE(cc_setup_national));
parsed = bsc_nat_parse(msg);
if (!parsed) {
printf("FAIL: Could not parse ID resp\n");
abort();
}
out = bsc_nat_rewrite_msg(nat, msg, parsed, imsi);
if (!out) {
printf("FAIL: A new message should be created.\n");
abort();
}
if (msg == out) {
printf("FAIL: The message should have changed\n");
abort();
}
verify_msg(out, cc_setup_national_patched, ARRAY_SIZE(cc_setup_national_patched));
msgb_free(out);
bsc_nat_num_rewr_entry_adapt(nat, &nat->num_rewr, NULL);
talloc_free(nat);
}
static void test_sms_smsc_rewrite()
{
struct msgb *msg = msgb_alloc(4096, "SMSC rewrite"), *out;
@ -1322,6 +1372,7 @@ int main(int argc, char **argv)
test_cr_filter();
test_dt_filter();
test_setup_rewrite();
test_setup_rewrite_prefix();
test_sms_smsc_rewrite();
test_sms_number_rewrite();
test_mgcp_allocations();

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@ -0,0 +1 @@
0172,0049
1 0172 0049

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@ -34,6 +34,7 @@ AT_CLEANUP
AT_SETUP([bsc-nat])
AT_KEYWORDS([bsc-nat])
AT_CHECK([test "$enable_nat_test" != no || exit 77])
cp $abs_srcdir/bsc-nat/prefixes.csv .
cp $abs_srcdir/bsc-nat/barr.cfg .
cp $abs_srcdir/bsc-nat/barr_dup.cfg .
cat $abs_srcdir/bsc-nat/bsc_nat_test.ok > expout

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@ -103,6 +103,27 @@ class TestVTYNAT(TestVTYBase):
res = self.vty.command("number-rewrite rewrite.cfg")
res = self.vty.command("no number-rewrite")
def testPrefixTreeLoading(self):
cfg = os.path.join(confpath, "tests/bsc-nat-trie/prefixes.csv")
self.vty.enable()
self.vty.command("configure terminal")
self.vty.command("nat")
res = self.vty.command("prefix-tree %s" % cfg)
self.assertEqual(res, "% prefix-tree loaded 17 rules.")
self.vty.command("end")
res = self.vty.command("show prefix-tree")
self.assertEqual(res, '1,1\r\n12,2\r\n123,3\r\n1234,4\r\n12345,5\r\n123456,6\r\n1234567,7\r\n12345678,8\r\n123456789,9\r\n1234567890,10\r\n13,11\r\n14,12\r\n15,13\r\n16,14\r\n82,16\r\n823455,15\r\n+49123,17')
self.vty.command("configure terminal")
self.vty.command("nat")
self.vty.command("no prefix-tree")
self.vty.command("end")
res = self.vty.command("show prefix-tree")
self.assertEqual(res, "% there is now prefix tree loaded.")
def add_nat_test(suite, workdir):
if not os.path.isfile(os.path.join(workdir, "src/osmo-bsc_nat/osmo-bsc_nat")):