Signed-off-by: Petr Vorel <pvorel@xxxxxxx>
---
Hi,
a patch to save searching for people using libmnl for manipulating IP
addresses.
Kind regards,
Petr
---
examples/rtnl/.gitignore | 1 +
examples/rtnl/Makefile.am | 6 +-
examples/rtnl/rtnl-addr-add.c | 119 ++++++++++++++++++++++++++++++++++
3 files changed, 125 insertions(+), 1 deletion(-)
create mode 100644 examples/rtnl/rtnl-addr-add.c
diff --git a/examples/rtnl/.gitignore b/examples/rtnl/.gitignore
index b03a27d..24ac633 100644
--- a/examples/rtnl/.gitignore
+++ b/examples/rtnl/.gitignore
@@ -1,3 +1,4 @@
+/rtnl-addr-add
/rtnl-link-dump
/rtnl-link-dump2
/rtnl-link-dump3
diff --git a/examples/rtnl/Makefile.am b/examples/rtnl/Makefile.am
index 174a4fb..dd8a77d 100644
--- a/examples/rtnl/Makefile.am
+++ b/examples/rtnl/Makefile.am
@@ -1,6 +1,7 @@
include $(top_srcdir)/Make_global.am
-check_PROGRAMS = rtnl-addr-dump \
+check_PROGRAMS = rtnl-addr-add \
+ rtnl-addr-dump \
rtnl-link-dump rtnl-link-dump2 rtnl-link-dump3 \
rtnl-link-event \
rtnl-link-set \
@@ -9,6 +10,9 @@ check_PROGRAMS = rtnl-addr-dump \
rtnl-route-event \
rtnl-neigh-dump
+rtnl_addr_add_SOURCES = rtnl-addr-add.c
+rtnl_addr_add_LDADD = ../../src/libmnl.la
+
rtnl_addr_dump_SOURCES = rtnl-addr-dump.c
rtnl_addr_dump_LDADD = ../../src/libmnl.la
diff --git a/examples/rtnl/rtnl-addr-add.c b/examples/rtnl/rtnl-addr-add.c
new file mode 100644
index 0000000..f0c2fda
--- /dev/null
+++ b/examples/rtnl/rtnl-addr-add.c
@@ -0,0 +1,119 @@
+/* This example is placed in the public domain. */
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <strings.h>
+#include <net/if.h>
+
+#include <libmnl/libmnl.h>
+#include <linux/if_link.h>
+#include <linux/rtnetlink.h>
+
+int main(int argc, char *argv[])
+{
+ struct mnl_socket *nl;
+ char buf[MNL_SOCKET_BUFFER_SIZE];
+ struct nlmsghdr *nlh;
+ struct ifaddrmsg *ifm;
+ uint32_t seq, portid;
+ union {
+ in_addr_t ip;
+ struct in6_addr ip6;
+ } addr;
+ int ret, family = AF_INET;
+
+ uint32_t prefix;
+ int iface;
+
+
+ if (argc <= 3) {
+ printf("Usage: %s iface destination cidr\n", argv[0]);
+ printf("Example: %s eth0 10.0.1.12 32\n", argv[0]);
+ printf(" %s eth0 ffff::10.0.1.12 128\n", argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
+ iface = if_nametoindex(argv[1]);
+ if (iface == 0) {
+ perror("if_nametoindex");
+ exit(EXIT_FAILURE);
+ }
+
+ if (!inet_pton(AF_INET, argv[2], &addr)) {
+ if (!inet_pton(AF_INET6, argv[2], &addr)) {
+ perror("inet_pton");
+ exit(EXIT_FAILURE);
+ }
+ family = AF_INET6;
+ }
+
+ if (sscanf(argv[3], "%u", &prefix) == 0) {
+ perror("sscanf");
+ exit(EXIT_FAILURE);
+ }
+
+ nlh = mnl_nlmsg_put_header(buf);
+ nlh->nlmsg_type = RTM_NEWADDR;
+
+ nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_ACK;
+ nlh->nlmsg_seq = seq = time(NULL);
+
+ ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(struct ifaddrmsg));
+
+ ifm->ifa_family = family;
+ ifm->ifa_prefixlen = prefix;
+ ifm->ifa_flags = IFA_F_PERMANENT;
+
+ ifm->ifa_scope = RT_SCOPE_UNIVERSE;
+ ifm->ifa_index = iface;
+
+ /*
+ * The exact meaning of IFA_LOCAL and IFA_ADDRESS depend
+ * on the address family being used and the device type.
+ * For broadcast devices (like the interfaces we use),
+ * for IPv4 we specify both and they are used interchangeably.
+ * For IPv6, only IFA_ADDRESS needs to be set.
+ */
+ if (family == AF_INET) {
+ mnl_attr_put_u32(nlh, IFA_LOCAL, addr.ip);
+ mnl_attr_put_u32(nlh, IFA_ADDRESS, addr.ip);
+ }
+ else
+ mnl_attr_put(nlh, IFA_ADDRESS, sizeof(struct in6_addr), &addr);
+
+ 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_sendto");
+ exit(EXIT_FAILURE);
+ }
+
+ ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
+ if (ret < 0) {
+ perror("mnl_socket_recvfrom");
+ exit(EXIT_FAILURE);
+ }
+
+ ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL);
+ if (ret < 0) {
+ perror("mnl_cb_run");
+ exit(EXIT_FAILURE);
+ }
+
+ mnl_socket_close(nl);
+
+ return 0;
+}
--
2.21.0
