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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:18:53 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:18:53 +0000
commita0e0018c9a7ef5ce7f6d2c3ae16aecbbd16a8f67 (patch)
tree8feaf1a1932871b139b3b30be4c09c66489918be /lib/ll_map.c
parentInitial commit. (diff)
downloadiproute2-upstream.tar.xz
iproute2-upstream.zip
Adding upstream version 6.1.0.upstream/6.1.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/ll_map.c')
-rw-r--r--lib/ll_map.c410
1 files changed, 410 insertions, 0 deletions
diff --git a/lib/ll_map.c b/lib/ll_map.c
new file mode 100644
index 0000000..70ea3d4
--- /dev/null
+++ b/lib/ll_map.c
@@ -0,0 +1,410 @@
+/*
+ * ll_map.c
+ *
+ * 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 <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <net/if.h>
+
+#include "libnetlink.h"
+#include "ll_map.h"
+#include "list.h"
+#include "utils.h"
+
+struct ll_cache {
+ struct hlist_node idx_hash;
+ struct hlist_node name_hash;
+ unsigned flags;
+ unsigned index;
+ unsigned short type;
+ struct list_head altnames_list;
+ char name[];
+};
+
+#define IDXMAP_SIZE 1024
+static struct hlist_head idx_head[IDXMAP_SIZE];
+static struct hlist_head name_head[IDXMAP_SIZE];
+
+static struct ll_cache *ll_get_by_index(unsigned index)
+{
+ struct hlist_node *n;
+ unsigned h = index & (IDXMAP_SIZE - 1);
+
+ hlist_for_each(n, &idx_head[h]) {
+ struct ll_cache *im
+ = container_of(n, struct ll_cache, idx_hash);
+ if (im->index == index)
+ return im;
+ }
+
+ return NULL;
+}
+
+unsigned namehash(const char *str)
+{
+ unsigned hash = 5381;
+
+ while (*str)
+ hash = ((hash << 5) + hash) + *str++; /* hash * 33 + c */
+
+ return hash;
+}
+
+static struct ll_cache *ll_get_by_name(const char *name)
+{
+ struct hlist_node *n;
+ unsigned h = namehash(name) & (IDXMAP_SIZE - 1);
+
+ hlist_for_each(n, &name_head[h]) {
+ struct ll_cache *im
+ = container_of(n, struct ll_cache, name_hash);
+
+ if (strcmp(im->name, name) == 0)
+ return im;
+ }
+
+ return NULL;
+}
+
+static struct ll_cache *ll_entry_create(struct ifinfomsg *ifi,
+ const char *ifname,
+ struct ll_cache *parent_im)
+{
+ struct ll_cache *im;
+ unsigned int h;
+
+ im = malloc(sizeof(*im) + strlen(ifname) + 1);
+ if (!im)
+ return NULL;
+ im->index = ifi->ifi_index;
+ strcpy(im->name, ifname);
+ im->type = ifi->ifi_type;
+ im->flags = ifi->ifi_flags;
+
+ if (parent_im) {
+ list_add_tail(&im->altnames_list, &parent_im->altnames_list);
+ } else {
+ /* This is parent, insert to index hash. */
+ h = ifi->ifi_index & (IDXMAP_SIZE - 1);
+ hlist_add_head(&im->idx_hash, &idx_head[h]);
+ INIT_LIST_HEAD(&im->altnames_list);
+ }
+
+ h = namehash(ifname) & (IDXMAP_SIZE - 1);
+ hlist_add_head(&im->name_hash, &name_head[h]);
+ return im;
+}
+
+static void ll_entry_destroy(struct ll_cache *im, bool im_is_parent)
+{
+ hlist_del(&im->name_hash);
+ if (im_is_parent)
+ hlist_del(&im->idx_hash);
+ else
+ list_del(&im->altnames_list);
+ free(im);
+}
+
+static void ll_entry_update(struct ll_cache *im, struct ifinfomsg *ifi,
+ const char *ifname)
+{
+ unsigned int h;
+
+ im->flags = ifi->ifi_flags;
+ if (!strcmp(im->name, ifname))
+ return;
+ hlist_del(&im->name_hash);
+ h = namehash(ifname) & (IDXMAP_SIZE - 1);
+ hlist_add_head(&im->name_hash, &name_head[h]);
+}
+
+static void ll_altname_entries_create(struct ll_cache *parent_im,
+ struct ifinfomsg *ifi, struct rtattr **tb)
+{
+ struct rtattr *i, *proplist = tb[IFLA_PROP_LIST];
+ int rem;
+
+ if (!proplist)
+ return;
+ rem = RTA_PAYLOAD(proplist);
+ for (i = RTA_DATA(proplist); RTA_OK(i, rem);
+ i = RTA_NEXT(i, rem)) {
+ if (i->rta_type != IFLA_ALT_IFNAME)
+ continue;
+ ll_entry_create(ifi, rta_getattr_str(i), parent_im);
+ }
+}
+
+static void ll_altname_entries_destroy(struct ll_cache *parent_im)
+{
+ struct ll_cache *im, *tmp;
+
+ list_for_each_entry_safe(im, tmp, &parent_im->altnames_list,
+ altnames_list)
+ ll_entry_destroy(im, false);
+}
+
+static void ll_altname_entries_update(struct ll_cache *parent_im,
+ struct ifinfomsg *ifi, struct rtattr **tb)
+{
+ struct rtattr *i, *proplist = tb[IFLA_PROP_LIST];
+ struct ll_cache *im;
+ int rem;
+
+ if (!proplist) {
+ ll_altname_entries_destroy(parent_im);
+ return;
+ }
+
+ /* Simply compare the altname list with the cached one
+ * and if it does not fit 1:1, recreate the cached list
+ * from scratch.
+ */
+ im = list_first_entry(&parent_im->altnames_list, typeof(*im),
+ altnames_list);
+ rem = RTA_PAYLOAD(proplist);
+ for (i = RTA_DATA(proplist); RTA_OK(i, rem);
+ i = RTA_NEXT(i, rem)) {
+ if (i->rta_type != IFLA_ALT_IFNAME)
+ continue;
+ if (!im || strcmp(rta_getattr_str(i), im->name))
+ goto recreate_altname_entries;
+ im = list_next_entry(im, altnames_list);
+ }
+ if (list_next_entry(im, altnames_list))
+ goto recreate_altname_entries;
+ return;
+
+recreate_altname_entries:
+ ll_altname_entries_destroy(parent_im);
+ ll_altname_entries_create(parent_im, ifi, tb);
+}
+
+static void ll_entries_create(struct ifinfomsg *ifi, struct rtattr **tb)
+{
+ struct ll_cache *parent_im;
+
+ if (!tb[IFLA_IFNAME])
+ return;
+ parent_im = ll_entry_create(ifi, rta_getattr_str(tb[IFLA_IFNAME]),
+ NULL);
+ if (!parent_im)
+ return;
+ ll_altname_entries_create(parent_im, ifi, tb);
+}
+
+static void ll_entries_destroy(struct ll_cache *parent_im)
+{
+ ll_altname_entries_destroy(parent_im);
+ ll_entry_destroy(parent_im, true);
+}
+
+static void ll_entries_update(struct ll_cache *parent_im,
+ struct ifinfomsg *ifi, struct rtattr **tb)
+{
+ if (tb[IFLA_IFNAME])
+ ll_entry_update(parent_im, ifi,
+ rta_getattr_str(tb[IFLA_IFNAME]));
+ ll_altname_entries_update(parent_im, ifi, tb);
+}
+
+int ll_remember_index(struct nlmsghdr *n, void *arg)
+{
+ struct ifinfomsg *ifi = NLMSG_DATA(n);
+ struct ll_cache *im;
+ struct rtattr *tb[IFLA_MAX+1];
+
+ if (n->nlmsg_type != RTM_NEWLINK && n->nlmsg_type != RTM_DELLINK)
+ return 0;
+
+ if (n->nlmsg_len < NLMSG_LENGTH(sizeof(*ifi)))
+ return -1;
+
+ im = ll_get_by_index(ifi->ifi_index);
+ if (n->nlmsg_type == RTM_DELLINK) {
+ if (im)
+ ll_entries_destroy(im);
+ return 0;
+ }
+
+ parse_rtattr_flags(tb, IFLA_MAX, IFLA_RTA(ifi),
+ IFLA_PAYLOAD(n), NLA_F_NESTED);
+ if (im)
+ ll_entries_update(im, ifi, tb);
+ else
+ ll_entries_create(ifi, tb);
+ return 0;
+}
+
+const char *ll_idx_n2a(unsigned int idx)
+{
+ static char buf[IFNAMSIZ];
+
+ snprintf(buf, sizeof(buf), "if%u", idx);
+ return buf;
+}
+
+static unsigned int ll_idx_a2n(const char *name)
+{
+ unsigned int idx;
+
+ if (sscanf(name, "if%u", &idx) != 1)
+ return 0;
+ return idx;
+}
+
+static int ll_link_get(const char *name, int index)
+{
+ struct {
+ struct nlmsghdr n;
+ struct ifinfomsg ifm;
+ char buf[1024];
+ } req = {
+ .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+ .n.nlmsg_flags = NLM_F_REQUEST,
+ .n.nlmsg_type = RTM_GETLINK,
+ .ifm.ifi_index = index,
+ };
+ __u32 filt_mask = RTEXT_FILTER_VF | RTEXT_FILTER_SKIP_STATS;
+ struct rtnl_handle rth = {};
+ struct nlmsghdr *answer;
+ int rc = 0;
+
+ if (rtnl_open(&rth, 0) < 0)
+ return 0;
+
+ addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask);
+ if (name)
+ addattr_l(&req.n, sizeof(req),
+ !check_ifname(name) ? IFLA_IFNAME : IFLA_ALT_IFNAME,
+ name, strlen(name) + 1);
+
+ if (rtnl_talk_suppress_rtnl_errmsg(&rth, &req.n, &answer) < 0)
+ goto out;
+
+ /* add entry to cache */
+ rc = ll_remember_index(answer, NULL);
+ if (!rc) {
+ struct ifinfomsg *ifm = NLMSG_DATA(answer);
+
+ rc = ifm->ifi_index;
+ }
+
+ free(answer);
+out:
+ rtnl_close(&rth);
+ return rc;
+}
+
+const char *ll_index_to_name(unsigned int idx)
+{
+ static char buf[IFNAMSIZ];
+ const struct ll_cache *im;
+
+ if (idx == 0)
+ return "*";
+
+ im = ll_get_by_index(idx);
+ if (im)
+ return im->name;
+
+ if (ll_link_get(NULL, idx) == idx) {
+ im = ll_get_by_index(idx);
+ if (im)
+ return im->name;
+ }
+
+ if (if_indextoname(idx, buf) == NULL)
+ snprintf(buf, IFNAMSIZ, "if%u", idx);
+
+ return buf;
+}
+
+int ll_index_to_type(unsigned idx)
+{
+ const struct ll_cache *im;
+
+ if (idx == 0)
+ return -1;
+
+ im = ll_get_by_index(idx);
+ return im ? im->type : -1;
+}
+
+int ll_index_to_flags(unsigned idx)
+{
+ const struct ll_cache *im;
+
+ if (idx == 0)
+ return 0;
+
+ im = ll_get_by_index(idx);
+ return im ? im->flags : -1;
+}
+
+unsigned ll_name_to_index(const char *name)
+{
+ const struct ll_cache *im;
+ unsigned idx;
+
+ if (name == NULL)
+ return 0;
+
+ im = ll_get_by_name(name);
+ if (im)
+ return im->index;
+
+ idx = ll_link_get(name, 0);
+ if (idx == 0)
+ idx = if_nametoindex(name);
+ if (idx == 0)
+ idx = ll_idx_a2n(name);
+ return idx;
+}
+
+void ll_drop_by_index(unsigned index)
+{
+ struct ll_cache *im;
+
+ im = ll_get_by_index(index);
+ if (!im)
+ return;
+
+ hlist_del(&im->idx_hash);
+ hlist_del(&im->name_hash);
+
+ free(im);
+}
+
+void ll_init_map(struct rtnl_handle *rth)
+{
+ static int initialized;
+
+ if (initialized)
+ return;
+
+ if (rtnl_linkdump_req(rth, AF_UNSPEC) < 0) {
+ perror("Cannot send dump request");
+ exit(1);
+ }
+
+ if (rtnl_dump_filter(rth, ll_remember_index, NULL) < 0) {
+ fprintf(stderr, "Dump terminated\n");
+ exit(1);
+ }
+
+ initialized = 1;
+}