diff options
Diffstat (limited to 'examples/rtnl/rtnl-route-dump.c')
-rw-r--r-- | examples/rtnl/rtnl-route-dump.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/examples/rtnl/rtnl-route-dump.c b/examples/rtnl/rtnl-route-dump.c new file mode 100644 index 0000000..34c95cf --- /dev/null +++ b/examples/rtnl/rtnl-route-dump.c @@ -0,0 +1,247 @@ +/* + * (C) 2009-2010 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * This software may be used and distributed according to the terms + * of the GNU General Public License, incorporated herein by reference. + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <time.h> +#include <arpa/inet.h> + +#include <libmnl/libmnl.h> +#include <linux/if.h> +#include <linux/if_link.h> +#include <linux/rtnetlink.h> + +static int data_attr_cb2(const struct nlattr *attr, void *data) +{ + /* skip unsupported attribute in user-space */ + if (mnl_attr_type_valid(attr, RTAX_MAX) < 0) + return MNL_CB_OK; + + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + return MNL_CB_OK; +} + +static void attributes_show_ipv4(struct nlattr *tb[]) +{ + if (tb[RTA_TABLE]) { + printf("table=%u ", mnl_attr_get_u32(tb[RTA_TABLE])); + } + if (tb[RTA_DST]) { + struct in_addr *addr = mnl_attr_get_payload(tb[RTA_DST]); + printf("dst=%s ", inet_ntoa(*addr)); + } + if (tb[RTA_SRC]) { + struct in_addr *addr = mnl_attr_get_payload(tb[RTA_SRC]); + printf("src=%s ", inet_ntoa(*addr)); + } + if (tb[RTA_OIF]) { + printf("oif=%u ", mnl_attr_get_u32(tb[RTA_OIF])); + } + if (tb[RTA_FLOW]) { + printf("flow=%u ", mnl_attr_get_u32(tb[RTA_FLOW])); + } + if (tb[RTA_PREFSRC]) { + struct in_addr *addr = mnl_attr_get_payload(tb[RTA_PREFSRC]); + printf("prefsrc=%s ", inet_ntoa(*addr)); + } + if (tb[RTA_GATEWAY]) { + struct in_addr *addr = mnl_attr_get_payload(tb[RTA_GATEWAY]); + printf("gw=%s ", inet_ntoa(*addr)); + } + if (tb[RTA_METRICS]) { + int i; + struct nlattr *tbx[RTAX_MAX+1] = {}; + + mnl_attr_parse_nested(tb[RTA_METRICS], data_attr_cb2, tbx); + + for (i=0; i<RTAX_MAX; i++) { + if (tbx[i]) { + printf("metrics[%d]=%u ", + i, mnl_attr_get_u32(tbx[i])); + } + } + } + printf("\n"); +} + +static int data_attr_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = (const struct nlattr **)data; + int type = mnl_attr_get_type(attr); + + /* skip unsupported attribute in user-space */ + if (mnl_attr_type_valid(attr, RTA_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case RTA_TABLE: + case RTA_DST: + case RTA_SRC: + case RTA_OIF: + case RTA_FLOW: + case RTA_PREFSRC: + case RTA_GATEWAY: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + case RTA_METRICS: + if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + tb[type] = attr; + return MNL_CB_OK; +} + +static int data_cb(const struct nlmsghdr *nlh, void *data) +{ + struct nlattr *tb[RTA_MAX+1] = {}; + struct rtmsg *rm = mnl_nlmsg_get_payload(nlh); + + /* protocol family = AF_INET | AF_INET6 */ + printf("family=%u ", rm->rtm_family); + + /* destination CIDR, eg. 24 or 32 for IPv4 */ + printf("dst_len=%u ", rm->rtm_dst_len); + + /* source CIDR */ + printf("src_len=%u ", rm->rtm_src_len); + + /* type of service (TOS), eg. 0 */ + printf("tos=%u ", rm->rtm_tos); + + /* table id: + * RT_TABLE_UNSPEC = 0 + * + * ... user defined values ... + * + * RT_TABLE_COMPAT = 252 + * RT_TABLE_DEFAULT = 253 + * RT_TABLE_MAIN = 254 + * RT_TABLE_LOCAL = 255 + * RT_TABLE_MAX = 0xFFFFFFFF + * + * Synonimous attribute: RTA_TABLE. + */ + printf("table=%u ", rm->rtm_table); + + /* type: + * RTN_UNSPEC = 0 + * RTN_UNICAST = 1 + * RTN_LOCAL = 2 + * RTN_BROADCAST = 3 + * RTN_ANYCAST = 4 + * RTN_MULTICAST = 5 + * RTN_BLACKHOLE = 6 + * RTN_UNREACHABLE = 7 + * RTN_PROHIBIT = 8 + * RTN_THROW = 9 + * RTN_NAT = 10 + * RTN_XRESOLVE = 11 + * __RTN_MAX = 12 + */ + printf("type=%u ", rm->rtm_type); + + /* scope: + * RT_SCOPE_UNIVERSE = 0 : everywhere in the universe + * + * ... user defined values ... + * + * RT_SCOPE_SITE = 200 + * RT_SCOPE_LINK = 253 : destination attached to link + * RT_SCOPE_HOST = 254 : local address + * RT_SCOPE_NOWHERE = 255 : not existing destination + */ + printf("scope=%u ", rm->rtm_scope); + + /* protocol: + * RTPROT_UNSPEC = 0 + * RTPROT_REDIRECT = 1 + * RTPROT_KERNEL = 2 : route installed by kernel + * RTPROT_BOOT = 3 : route installed during boot + * RTPROT_STATIC = 4 : route installed by administrator + * + * Values >= RTPROT_STATIC are not interpreted by kernel, they are + * just user-defined. + */ + printf("proto=%u ", rm->rtm_protocol); + + /* flags: + * RTM_F_NOTIFY = 0x100: notify user of route change + * RTM_F_CLONED = 0x200: this route is cloned + * RTM_F_EQUALIZE = 0x400: Multipath equalizer: NI + * RTM_F_PREFIX = 0x800: Prefix addresses + */ + printf("flags=%x\n", rm->rtm_flags); + + mnl_attr_parse(nlh, sizeof(*rm), data_attr_cb, tb); + + switch(rm->rtm_family) { + case AF_INET: + attributes_show_ipv4(tb); + break; + } + + return MNL_CB_OK; +} + +int main() +{ + struct mnl_socket *nl; + char buf[getpagesize()]; + struct nlmsghdr *nlh; + struct rtmsg *rtm; + int ret; + unsigned int seq, portid; + + nlh = mnl_nlmsg_put_header(buf); + nlh->nlmsg_type = RTM_GETROUTE; + nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; + nlh->nlmsg_seq = seq = time(NULL); + rtm = mnl_nlmsg_put_extra_header(nlh, sizeof(struct rtmsg)); + rtm->rtm_family = AF_INET; + + nl = mnl_socket_open(NETLINK_ROUTE); + if (nl == NULL) { + perror("mnl_socket_open"); + exit(EXIT_FAILURE); + } + + if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { + perror("mnl_socket_bind"); + exit(EXIT_FAILURE); + } + portid = mnl_socket_get_portid(nl); + + if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { + perror("mnl_socket_send"); + exit(EXIT_FAILURE); + } + + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + while (ret > 0) { + ret = mnl_cb_run(buf, ret, seq, portid, data_cb, NULL); + if (ret <= MNL_CB_STOP) + break; + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + } + if (ret == -1) { + perror("error"); + exit(EXIT_FAILURE); + } + + mnl_socket_close(nl); + + return 0; +} |