Review at https://gerrit.osmocom.org/4291
tun: Convert tun_ipv6_linklocal_get to be more generic
Add support for IPv4 and IPv6 global IPs. Also return the prefix length
of the IP address by using a in46_prefix.
Change-Id: I277af191dc611b6bbcb83479f4ae338083740322
---
M ggsn/ggsn.c
M lib/tun.c
M lib/tun.h
3 files changed, 55 insertions(+), 14 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-ggsn refs/changes/91/4291/1
diff --git a/ggsn/ggsn.c b/ggsn/ggsn.c
index 29d8473..c04d32e 100644
--- a/ggsn/ggsn.c
+++ b/ggsn/ggsn.c
@@ -149,6 +149,7 @@
/* actually start the APN with its current config */
int apn_start(struct apn_ctx *apn)
{
+ struct in46_prefix ipv6_tun_linklocal_ip;
if (apn->started)
return 0;
@@ -201,12 +202,13 @@
}
if (apn->cfg.apn_type_mask & (APN_TYPE_IPv6|APN_TYPE_IPv4v6)) {
- if (tun_ipv6_linklocal_get(apn->tun.tun,
&apn->v6_lladdr) < 0) {
+ if (tun_ip_local_get(apn->tun.tun,
&ipv6_tun_linklocal_ip, IP_TYPE_IPv6_LINK) < 0) {
LOGPAPN(LOGL_ERROR, apn, "Cannot obtain IPv6
link-local address of "
"interface: %s\n", strerror(errno));
apn_stop(apn, false);
return -1;
}
+ apn->v6_lladdr = ipv6_tun_linklocal_ip.addr.v6;
}
/* set back-pointer from TUN device to APN */
diff --git a/lib/tun.c b/lib/tun.c
index 7662146..e8b55db 100644
--- a/lib/tun.c
+++ b/lib/tun.c
@@ -751,34 +751,63 @@
#include <ifaddrs.h>
-/* obtain the link-local address of the tun device */
-int tun_ipv6_linklocal_get(const struct tun_t *tun, struct in6_addr *ia)
+/*! Obtain the local address of the tun device.
+ * \param[in] tun Target device owning the IP
+ * \param[out] prefix Structure to fill with an IPv4/6 and prefix length
+ * \param[in] flags Specify which kind of IP to look for: IP_TYPE_IPv4,
IP_TYPE_IPv6_LINK, IP_TYPE_IPv6_GLOBAL
+ * \returns 0 if the IP was found and prefix structure was filled
successfully, -1 othwerise
+ */
+int tun_ip_local_get(const struct tun_t *tun, struct in46_prefix *prefix, int
flags)
{
- struct ifaddrs *ifaddr, *ifa;
static const uint8_t ll_prefix[] = { 0xfe,0x80, 0,0, 0,0, 0,0 };
+ struct ifaddrs *ifaddr, *ifa;
+ struct in46_addr netmask;
+ bool is_ipv6_ll;
if (getifaddrs(&ifaddr) == -1) {
return -1;
}
for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
- struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)
ifa->ifa_addr;
if (ifa->ifa_addr == NULL)
- continue;
-
- if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
if (strcmp(ifa->ifa_name, tun->devname))
continue;
- if (memcmp(sin6->sin6_addr.s6_addr, ll_prefix,
sizeof(ll_prefix)))
- continue;
+ if (ifa->ifa_addr->sa_family == AF_INET && (flags &
IP_TYPE_IPv4)) {
+ struct sockaddr_in *sin4 = (struct sockaddr_in *)
ifa->ifa_addr;
+ struct sockaddr_in *netmask4 = (struct sockaddr_in *)
ifa->ifa_netmask;
- *ia = sin6->sin6_addr;
- freeifaddrs(ifaddr);
- return 0;
+ netmask.len = sizeof(netmask4->sin_addr);
+ netmask.v4 = netmask4->sin_addr;
+ prefix->addr.len = sizeof(sin4->sin_addr);
+ prefix->addr.v4 = sin4->sin_addr;
+ prefix->prefixlen = in46a_netmasklen(&netmask);
+ freeifaddrs(ifaddr);
+ return 0;
+ }
+
+ if (ifa->ifa_addr->sa_family == AF_INET6 && (flags &
IP_TYPE_IPv6)) {
+ struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)
ifa->ifa_addr;
+ struct sockaddr_in6 *netmask6 = (struct sockaddr_in6 *)
ifa->ifa_netmask;
+
+ is_ipv6_ll = !memcmp(sin6->sin6_addr.s6_addr,
ll_prefix, sizeof(ll_prefix));
+ if ((flags & IP_TYPE_IPv6_GLOBAL) && is_ipv6_ll)
+ continue;
+ if ((flags & IP_TYPE_IPv6_LINK) && !is_ipv6_ll)
+ continue;
+
+ netmask.len = sizeof(netmask6->sin6_addr);
+ netmask.v6 = netmask6->sin6_addr;
+ prefix->addr.len = sizeof(sin6->sin6_addr);
+ prefix->addr.v6 = sin6->sin6_addr;
+ prefix->prefixlen = in46a_netmasklen(&netmask);
+ freeifaddrs(ifaddr);
+ return 0;
+ }
}
+
freeifaddrs(ifaddr);
return -1;
}
diff --git a/lib/tun.h b/lib/tun.h
index f63be50..c50f907 100644
--- a/lib/tun.h
+++ b/lib/tun.h
@@ -23,6 +23,16 @@
#define TUN_NLBUFSIZE 1024
#include "config.h"
+
+/* ipv6 ip type flags for tun_ipv6_local_get() */
+enum {
+ IP_TYPE_IPv4 = 1,
+ IP_TYPE_IPv6_LINK = 2,
+ IP_TYPE_IPv6_GLOBAL = 4,
+};
+#define IP_TYPE_IPv6 (IP_TYPE_IPv6_LINK | IP_TYPE_IPv6_GLOBAL)
+
+
#ifndef HAVE_IPHDR
struct iphdr
{
@@ -85,6 +95,6 @@
extern int tun_runscript(struct tun_t *tun, char *script);
-int tun_ipv6_linklocal_get(const struct tun_t *tun, struct in6_addr *ia);
+int tun_ip_local_get(const struct tun_t *tun, struct in46_prefix *prefix, int
flags);
#endif /* !_TUN_H */
--
To view, visit https://gerrit.osmocom.org/4291
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Gerrit-MessageType: newchange
Gerrit-Change-Id: I277af191dc611b6bbcb83479f4ae338083740322
Gerrit-PatchSet: 1
Gerrit-Project: osmo-ggsn
Gerrit-Branch: master
Gerrit-Owner: Pau Espin Pedrol <[email protected]>
