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Diffstat (limited to 'networking/libiproute/libnetlink.c')
-rw-r--r--networking/libiproute/libnetlink.c521
1 files changed, 521 insertions, 0 deletions
diff --git a/networking/libiproute/libnetlink.c b/networking/libiproute/libnetlink.c
new file mode 100644
index 0000000..a1f39d4
--- /dev/null
+++ b/networking/libiproute/libnetlink.c
@@ -0,0 +1,521 @@
+/*
+ * libnetlink.c RTnetlink service routines.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <fcntl.h>
+#include <net/if_arp.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <errno.h>
+#include <time.h>
+#include <sys/uio.h>
+
+#include "libnetlink.h"
+
+void rtnl_close(struct rtnl_handle *rth)
+{
+ close(rth->fd);
+}
+
+int rtnl_open(struct rtnl_handle *rth, unsigned subscriptions)
+{
+ int addr_len;
+
+ memset(rth, 0, sizeof(rth));
+
+ rth->fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (rth->fd < 0) {
+ perror("Cannot open netlink socket");
+ return -1;
+ }
+
+ memset(&rth->local, 0, sizeof(rth->local));
+ rth->local.nl_family = AF_NETLINK;
+ rth->local.nl_groups = subscriptions;
+
+ if (bind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local)) < 0) {
+ perror("Cannot bind netlink socket");
+ return -1;
+ }
+ addr_len = sizeof(rth->local);
+ if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0) {
+ perror("Cannot getsockname");
+ return -1;
+ }
+ if (addr_len != sizeof(rth->local)) {
+ fprintf(stderr, "Wrong address length %d\n", addr_len);
+ return -1;
+ }
+ if (rth->local.nl_family != AF_NETLINK) {
+ fprintf(stderr, "Wrong address family %d\n", rth->local.nl_family);
+ return -1;
+ }
+ rth->seq = time(NULL);
+ return 0;
+}
+
+int rtnl_wilddump_request(struct rtnl_handle *rth, int family, int type)
+{
+ struct {
+ struct nlmsghdr nlh;
+ struct rtgenmsg g;
+ } req;
+ struct sockaddr_nl nladdr;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+
+ req.nlh.nlmsg_len = sizeof(req);
+ req.nlh.nlmsg_type = type;
+ req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
+ req.nlh.nlmsg_pid = 0;
+ req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
+ req.g.rtgen_family = family;
+
+ return sendto(rth->fd, (void*)&req, sizeof(req), 0, (struct sockaddr*)&nladdr, sizeof(nladdr));
+}
+
+int rtnl_send(struct rtnl_handle *rth, char *buf, int len)
+{
+ struct sockaddr_nl nladdr;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+
+ return sendto(rth->fd, buf, len, 0, (struct sockaddr*)&nladdr, sizeof(nladdr));
+}
+
+int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
+{
+ struct nlmsghdr nlh;
+ struct sockaddr_nl nladdr;
+ struct iovec iov[2] = { { &nlh, sizeof(nlh) }, { req, len } };
+ struct msghdr msg = {
+ (void*)&nladdr, sizeof(nladdr),
+ iov, 2,
+ NULL, 0,
+ 0
+ };
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+
+ nlh.nlmsg_len = NLMSG_LENGTH(len);
+ nlh.nlmsg_type = type;
+ nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
+ nlh.nlmsg_pid = 0;
+ nlh.nlmsg_seq = rth->dump = ++rth->seq;
+
+ return sendmsg(rth->fd, &msg, 0);
+}
+
+int rtnl_dump_filter(struct rtnl_handle *rth,
+ int (*filter)(struct sockaddr_nl *, struct nlmsghdr *n, void *),
+ void *arg1,
+ int (*junk)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
+ void *arg2)
+{
+ char buf[8192];
+ struct sockaddr_nl nladdr;
+ struct iovec iov = { buf, sizeof(buf) };
+
+ while (1) {
+ int status;
+ struct nlmsghdr *h;
+
+ struct msghdr msg = {
+ (void*)&nladdr, sizeof(nladdr),
+ &iov, 1,
+ NULL, 0,
+ 0
+ };
+
+ status = recvmsg(rth->fd, &msg, 0);
+
+ if (status < 0) {
+ if (errno == EINTR)
+ continue;
+ perror("OVERRUN");
+ continue;
+ }
+ if (status == 0) {
+ fprintf(stderr, "EOF on netlink\n");
+ return -1;
+ }
+ if (msg.msg_namelen != sizeof(nladdr)) {
+ fprintf(stderr, "sender address length == %d\n", msg.msg_namelen);
+ exit(1);
+ }
+
+ h = (struct nlmsghdr*)buf;
+ while (NLMSG_OK(h, status)) {
+ int err;
+
+ if (h->nlmsg_pid != rth->local.nl_pid ||
+ h->nlmsg_seq != rth->dump) {
+ if (junk) {
+ err = junk(&nladdr, h, arg2);
+ if (err < 0)
+ return err;
+ }
+ goto skip_it;
+ }
+
+ if (h->nlmsg_type == NLMSG_DONE)
+ return 0;
+ if (h->nlmsg_type == NLMSG_ERROR) {
+ struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
+ if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
+ fprintf(stderr, "ERROR truncated\n");
+ } else {
+ errno = -err->error;
+ perror("RTNETLINK answers");
+ }
+ return -1;
+ }
+ err = filter(&nladdr, h, arg1);
+ if (err < 0)
+ return err;
+
+skip_it:
+ h = NLMSG_NEXT(h, status);
+ }
+ if (msg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "Message truncated\n");
+ continue;
+ }
+ if (status) {
+ fprintf(stderr, "!!!Remnant of size %d\n", status);
+ exit(1);
+ }
+ }
+}
+
+int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,
+ unsigned groups, struct nlmsghdr *answer,
+ int (*junk)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
+ void *jarg)
+{
+ int status;
+ unsigned seq;
+ struct nlmsghdr *h;
+ struct sockaddr_nl nladdr;
+ struct iovec iov = { (void*)n, n->nlmsg_len };
+ char buf[8192];
+ struct msghdr msg = {
+ (void*)&nladdr, sizeof(nladdr),
+ &iov, 1,
+ NULL, 0,
+ 0
+ };
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = peer;
+ nladdr.nl_groups = groups;
+
+ n->nlmsg_seq = seq = ++rtnl->seq;
+ if (answer == NULL)
+ n->nlmsg_flags |= NLM_F_ACK;
+
+ status = sendmsg(rtnl->fd, &msg, 0);
+
+ if (status < 0) {
+ perror("Cannot talk to rtnetlink");
+ return -1;
+ }
+
+ iov.iov_base = buf;
+
+ while (1) {
+ iov.iov_len = sizeof(buf);
+ status = recvmsg(rtnl->fd, &msg, 0);
+
+ if (status < 0) {
+ if (errno == EINTR)
+ continue;
+ perror("OVERRUN");
+ continue;
+ }
+ if (status == 0) {
+ fprintf(stderr, "EOF on netlink\n");
+ return -1;
+ }
+ if (msg.msg_namelen != sizeof(nladdr)) {
+ fprintf(stderr, "sender address length == %d\n", msg.msg_namelen);
+ exit(1);
+ }
+ for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
+ int err;
+ int len = h->nlmsg_len;
+ int l = len - sizeof(*h);
+
+ if (l<0 || len>status) {
+ if (msg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "Truncated message\n");
+ return -1;
+ }
+ fprintf(stderr, "!!!malformed message: len=%d\n", len);
+ exit(1);
+ }
+
+ if (h->nlmsg_pid != rtnl->local.nl_pid ||
+ h->nlmsg_seq != seq) {
+ if (junk) {
+ err = junk(&nladdr, h, jarg);
+ if (err < 0)
+ return err;
+ }
+ continue;
+ }
+
+ if (h->nlmsg_type == NLMSG_ERROR) {
+ struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
+ if (l < sizeof(struct nlmsgerr)) {
+ fprintf(stderr, "ERROR truncated\n");
+ } else {
+ errno = -err->error;
+ if (errno == 0) {
+ if (answer)
+ memcpy(answer, h, h->nlmsg_len);
+ return 0;
+ }
+ perror("RTNETLINK answers");
+ }
+ return -1;
+ }
+ if (answer) {
+ memcpy(answer, h, h->nlmsg_len);
+ return 0;
+ }
+
+ fprintf(stderr, "Unexpected reply!!!\n");
+
+ status -= NLMSG_ALIGN(len);
+ h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
+ }
+ if (msg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "Message truncated\n");
+ continue;
+ }
+ if (status) {
+ fprintf(stderr, "!!!Remnant of size %d\n", status);
+ exit(1);
+ }
+ }
+}
+
+int rtnl_listen(struct rtnl_handle *rtnl,
+ int (*handler)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
+ void *jarg)
+{
+ int status;
+ struct nlmsghdr *h;
+ struct sockaddr_nl nladdr;
+ struct iovec iov;
+ char buf[8192];
+ struct msghdr msg = {
+ (void*)&nladdr, sizeof(nladdr),
+ &iov, 1,
+ NULL, 0,
+ 0
+ };
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = 0;
+ nladdr.nl_groups = 0;
+
+
+ iov.iov_base = buf;
+
+ while (1) {
+ iov.iov_len = sizeof(buf);
+ status = recvmsg(rtnl->fd, &msg, 0);
+
+ if (status < 0) {
+ if (errno == EINTR)
+ continue;
+ perror("OVERRUN");
+ continue;
+ }
+ if (status == 0) {
+ fprintf(stderr, "EOF on netlink\n");
+ return -1;
+ }
+ if (msg.msg_namelen != sizeof(nladdr)) {
+ fprintf(stderr, "Sender address length == %d\n", msg.msg_namelen);
+ exit(1);
+ }
+ for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
+ int err;
+ int len = h->nlmsg_len;
+ int l = len - sizeof(*h);
+
+ if (l<0 || len>status) {
+ if (msg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "Truncated message\n");
+ return -1;
+ }
+ fprintf(stderr, "!!!malformed message: len=%d\n", len);
+ exit(1);
+ }
+
+ err = handler(&nladdr, h, jarg);
+ if (err < 0)
+ return err;
+
+ status -= NLMSG_ALIGN(len);
+ h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
+ }
+ if (msg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "Message truncated\n");
+ continue;
+ }
+ if (status) {
+ fprintf(stderr, "!!!Remnant of size %d\n", status);
+ exit(1);
+ }
+ }
+}
+
+int rtnl_from_file(FILE *rtnl,
+ int (*handler)(struct sockaddr_nl *,struct nlmsghdr *n, void *),
+ void *jarg)
+{
+ int status;
+ struct sockaddr_nl nladdr;
+ char buf[8192];
+ struct nlmsghdr *h = (void*)buf;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = 0;
+ nladdr.nl_groups = 0;
+
+ while (1) {
+ int err, len, type;
+ int l;
+
+ status = fread(&buf, 1, sizeof(*h), rtnl);
+
+ if (status < 0) {
+ if (errno == EINTR)
+ continue;
+ perror("rtnl_from_file: fread");
+ return -1;
+ }
+ if (status == 0)
+ return 0;
+
+ len = h->nlmsg_len;
+ type= h->nlmsg_type;
+ l = len - sizeof(*h);
+
+ if (l<0 || len>sizeof(buf)) {
+ fprintf(stderr, "!!!malformed message: len=%d @%lu\n",
+ len, ftell(rtnl));
+ return -1;
+ }
+
+ status = fread(NLMSG_DATA(h), 1, NLMSG_ALIGN(l), rtnl);
+
+ if (status < 0) {
+ perror("rtnl_from_file: fread");
+ return -1;
+ }
+ if (status < l) {
+ fprintf(stderr, "rtnl-from_file: truncated message\n");
+ return -1;
+ }
+
+ err = handler(&nladdr, h, jarg);
+ if (err < 0)
+ return err;
+ }
+}
+
+int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
+{
+ int len = RTA_LENGTH(4);
+ struct rtattr *rta;
+ if (NLMSG_ALIGN(n->nlmsg_len) + len > maxlen)
+ return -1;
+ rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len));
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy(RTA_DATA(rta), &data, 4);
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
+ return 0;
+}
+
+int addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen)
+{
+ int len = RTA_LENGTH(alen);
+ struct rtattr *rta;
+
+ if (NLMSG_ALIGN(n->nlmsg_len) + len > maxlen)
+ return -1;
+ rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len));
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy(RTA_DATA(rta), data, alen);
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
+ return 0;
+}
+
+int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data)
+{
+ int len = RTA_LENGTH(4);
+ struct rtattr *subrta;
+
+ if (RTA_ALIGN(rta->rta_len) + len > maxlen)
+ return -1;
+ subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
+ subrta->rta_type = type;
+ subrta->rta_len = len;
+ memcpy(RTA_DATA(subrta), &data, 4);
+ rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
+ return 0;
+}
+
+int rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data, int alen)
+{
+ struct rtattr *subrta;
+ int len = RTA_LENGTH(alen);
+
+ if (RTA_ALIGN(rta->rta_len) + len > maxlen)
+ return -1;
+ subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
+ subrta->rta_type = type;
+ subrta->rta_len = len;
+ memcpy(RTA_DATA(subrta), data, alen);
+ rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
+ return 0;
+}
+
+
+int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
+{
+ while (RTA_OK(rta, len)) {
+ if (rta->rta_type <= max)
+ tb[rta->rta_type] = rta;
+ rta = RTA_NEXT(rta,len);
+ }
+ if (len)
+ fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
+ return 0;
+}