Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Disregard route if update is a subnet of tun's address #676

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
Open

Disregard route if update is a subnet of tun's address #676

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
62 changes: 57 additions & 5 deletions programs/ziti-edge-tunnel/netif_driver/linux/tun.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -126,6 +126,36 @@ static void route_updates_done(uv_work_t *wr, int status) {
free(wr);
}

static int ipv6_equal_prefix(const struct in6_addr *addr1, const struct in6_addr *addr2, unsigned int prefixlen)
{
const uint32_t *a1 = addr1->s6_addr32;
const uint32_t *a2 = addr2->s6_addr32;
unsigned int nw = prefixlen / 32;
unsigned int nb = prefixlen % 32;

if (memcmp(a1, a2, 4*nw))
return 0;

return !(nb && ((a1[nw] ^ a2[nw]) & htonl(0xffffffffUL << (32 - nb))));
}

static int tun_check_prefix(netif_handle tun, const char *cidr)
{
ziti_address *ifa = &tun->addr;
ziti_address range;

if (parse_ziti_address_str(&range, cidr) < 0 || range.type != ziti_address_cidr)
return -1;

if (range.addr.cidr.af != ifa->addr.cidr.af)
return -1;

if (range.addr.cidr.bits < ifa->addr.cidr.bits)
return 0;

return ipv6_equal_prefix(&range.addr.cidr.ip, &ifa->addr.cidr.ip, ifa->addr.cidr.bits);
}

static void process_routes_updates(uv_work_t *wr) {
struct rt_process_cmd *cmd = wr->data;

Expand Down Expand Up @@ -153,6 +183,12 @@ static void process_routes_updates(uv_work_t *wr) {
// action == 1: add
unsigned action = (uintptr_t) value;
if (action == i) {
/*
* Ignore update if the prefix is a subnetwork of the tun's network
*/
if (tun_check_prefix(cmd->tun, prefix) > 0)
continue;

int len = snprintf(buf, sizeof(buf), "route %s %s dev %s\n", verb, prefix, cmd->tun->name);
if (len < 0 || (size_t) len >= sizeof buf) {
if (len > 0) errno = ENOMEM;
Expand Down Expand Up @@ -450,16 +486,32 @@ netif_driver tun_open(uv_loop_t *loop, uint32_t tun_ip, uint32_t dns_ip, const c
driver->exclude_rt = tun_exclude_rt;
driver->commit_routes = tun_commit_routes;

ziti_address range;
unsigned int prefixlen;
if (!dns_block ||
parse_ziti_address_str(&range, dns_block) < 0 ||
range.type != ziti_address_cidr ||
range.addr.cidr.bits > 32) {
prefixlen = 32;
} else {
prefixlen = range.addr.cidr.bits;
}
tun->addr = (ziti_address) {
.type = ziti_address_cidr,
.addr.cidr.af = AF_INET,
.addr.cidr.bits = prefixlen,
.addr.cidr.ip = { .s6_addr32 = { tun_ip } }
};

run_command("ip link set %s up", tun->name);
run_command("ip addr add %s dev %s", inet_ntoa(*(struct in_addr*)&tun_ip), tun->name);
run_command("ip addr add %s/%d dev %s",
inet_ntoa((struct in_addr){ .s_addr = tun->addr.addr.cidr.ip.s6_addr32[0] }),
tun->addr.addr.cidr.bits,
tun->name);

if (dns_ip) {
init_dns_maintainer(loop, tun->name, dns_ip);
}

if (dns_block) {
run_command("ip route add %s dev %s", dns_block, tun->name);
}

return driver;
}
1 change: 1 addition & 0 deletions programs/ziti-edge-tunnel/netif_driver/linux/tun.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@
struct netif_handle_s {
int fd;
char name[IFNAMSIZ];
ziti_address addr;

model_map *route_updates;
};
Expand Down