diff options
author | Pau Espin Pedrol <pespin@sysmocom.de> | 2017-10-16 14:41:37 +0200 |
---|---|---|
committer | Pau Espin Pedrol <pespin@sysmocom.de> | 2017-10-16 17:45:48 +0200 |
commit | a037e5908a84e8f438f8faef662f6bfcec305b16 (patch) | |
tree | 1d32b511c1e24bed412bc1350e2167537f38bc53 /lib | |
parent | 2e7b9ff891a0d4c84a4be3fffbac1b9502fe267c (diff) |
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
Diffstat (limited to 'lib')
-rw-r--r-- | lib/tun.c | 65 | ||||
-rw-r--r-- | lib/tun.h | 13 |
2 files changed, 64 insertions, 14 deletions
@@ -751,34 +751,73 @@ int tun_runscript(struct tun_t *tun, char *script) #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_list List of prefix structures to fill with each IPv4/6 and prefix length found. + * \param[in] prefix_size Amount of elements allowed to be fill in the prefix_list array. + * \param[in] flags Specify which kind of IP to look for: IP_TYPE_IPv4, IP_TYPE_IPv6_LINK, IP_TYPE_IPv6_NONLINK + * \returns The number of ips found following the criteria specified by flags, -1 on error. + * + * This function will fill prefix_list with up to prefix_size IPs following the + * criteria specified by flags parameter. It returns the number of IPs matching + * the criteria. As a result, the number returned can be bigger than + * prefix_size. It can be used with prefix_size=0 to get an estimate of the size + * needed for prefix_list. + */ +int tun_ip_local_get(const struct tun_t *tun, struct in46_prefix *prefix_list, size_t prefix_size, 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; + size_t count = 0; + 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; + if (count < prefix_size) { + netmask.len = sizeof(netmask4->sin_addr); + netmask.v4 = netmask4->sin_addr; + prefix_list[count].addr.len = sizeof(sin4->sin_addr); + prefix_list[count].addr.v4 = sin4->sin_addr; + prefix_list[count].prefixlen = in46a_netmasklen(&netmask); + } + count++; + } + + 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_NONLINK) && is_ipv6_ll) + continue; + if ((flags & IP_TYPE_IPv6_LINK) && !is_ipv6_ll) + continue; + + if (count < prefix_size) { + netmask.len = sizeof(netmask6->sin6_addr); + netmask.v6 = netmask6->sin6_addr; + prefix_list[count].addr.len = sizeof(sin6->sin6_addr); + prefix_list[count].addr.v6 = sin6->sin6_addr; + prefix_list[count].prefixlen = in46a_netmasklen(&netmask); + } + count++; + } } + freeifaddrs(ifaddr); - return -1; + return count; } @@ -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_NONLINK = 4, +}; +#define IP_TYPE_IPv6 (IP_TYPE_IPv6_LINK | IP_TYPE_IPv6_NONLINK) + + #ifndef HAVE_IPHDR struct iphdr { @@ -85,6 +95,7 @@ extern int tun_set_cb_ind(struct tun_t *this, 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_list, + size_t prefix_size, int flags); #endif /* !_TUN_H */ |