+/*
+ * lib/fib_lookup/lookup.c FIB Lookup
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch>
+ */
+
+/**
+ * @defgroup fib_lookup FIB Lookup
+ * @brief
+ * @{
+ */
+
+#include <netlink-local.h>
+#include <netlink/netlink.h>
+#include <netlink/attr.h>
+#include <netlink/utils.h>
+#include <netlink/object.h>
+#include <netlink/route/rtnl.h>
+#include <netlink/route/route.h>
+#include <netlink/fib_lookup/request.h>
+#include <netlink/fib_lookup/lookup.h>
+
+/** @cond SKIP */
+static struct nl_cache_ops fib_lookup_ops;
+
+/* not exported so far */
+struct fib_result_nl {
+ uint32_t fl_addr; /* To be looked up*/
+ uint32_t fl_fwmark;
+ unsigned char fl_tos;
+ unsigned char fl_scope;
+ unsigned char tb_id_in;
+
+ unsigned char tb_id; /* Results */
+ unsigned char prefixlen;
+ unsigned char nh_sel;
+ unsigned char type;
+ unsigned char scope;
+ int err;
+};
+/** @endcond */
+
+static void result_free_data(struct nl_object *obj)
+{
+ struct flnl_result *res = nl_object_priv(obj);
+
+ if (res && res->fr_req)
+ flnl_request_put(res->fr_req);
+}
+
+static int result_msg_parser(struct sockaddr_nl *who, struct nlmsghdr *n,
+ void *arg)
+{
+ struct flnl_result *res;
+ struct fib_result_nl *fr;
+ struct nl_parser_param *pp = arg;
+ struct nl_addr *addr;
+ int err = -EINVAL;
+
+ res = flnl_result_alloc();
+ if (!res)
+ goto errout;
+
+ res->ce_msgtype = n->nlmsg_type;
+
+ res->fr_req = flnl_request_alloc();
+ if (!res->fr_req)
+ goto errout;
+
+ fr = nlmsg_data(n);
+ addr = nl_addr_build(AF_INET, &fr->fl_addr, 4);
+ if (!addr)
+ goto errout;
+ err = flnl_request_set_addr(res->fr_req, addr);
+ nl_addr_put(addr);
+ if (err < 0)
+ goto errout;
+
+ flnl_request_set_fwmark(res->fr_req, fr->fl_fwmark);
+ flnl_request_set_tos(res->fr_req, fr->fl_tos);
+ flnl_request_set_scope(res->fr_req, fr->fl_scope);
+ flnl_request_set_table(res->fr_req, fr->tb_id_in);
+
+ res->fr_table_id = fr->tb_id;
+ res->fr_prefixlen = fr->prefixlen;
+ res->fr_nh_sel = fr->nh_sel;
+ res->fr_type = fr->type;
+ res->fr_scope = fr->scope;
+ res->fr_error = fr->err;
+
+ err = pp->pp_cb((struct nl_object *) res, pp);
+ if (err < 0)
+ goto errout;
+
+ /* REAL HACK, fib_lookup doesn't support ACK nor does it
+ * send a DONE message, enforce end of message stream
+ * after just the first message */
+ return NL_EXIT;
+
+errout:
+ flnl_result_put(res);
+ return err;
+}
+
+static int result_dump_brief(struct nl_object *obj, struct nl_dump_params *p)
+{
+ struct flnl_result *res = (struct flnl_result *) obj;
+ char buf[128];
+ int line = 1;
+
+ dp_dump(p, "table %s prefixlen %u next-hop-selector %u\n",
+ rtnl_route_table2str(res->fr_table_id, buf, sizeof(buf)),
+ res->fr_prefixlen, res->fr_nh_sel);
+ dp_dump_line(p, line++, "type %s ",
+ nl_rtntype2str(res->fr_type, buf, sizeof(buf)));
+ dp_dump(p, "scope %s error %s (%d)\n",
+ rtnl_scope2str(res->fr_scope, buf, sizeof(buf)),
+ strerror(-res->fr_error), res->fr_error);
+
+ return line;
+}
+
+static int result_dump_full(struct nl_object *obj, struct nl_dump_params *p)
+{
+ return result_dump_brief(obj, p);
+}
+
+static int result_filter(struct nl_object *obj, struct nl_object *filter)
+{
+ struct flnl_result *o = (struct flnl_result *) obj;
+ struct flnl_result *f = (struct flnl_result *) filter;
+
+ if (o->fr_req && f->fr_req)
+ return flnl_request_cmp(o->fr_req, f->fr_req);
+
+ return 1;
+}
+
+/**
+ * @name FIB Result Allocation/Freeage
+ * @{
+ */
+
+/**
+ * Allocate and initialize new lookup result object.
+ * @note Free the memory after usage using flnl_result_put() or
+ * flnl_result_free().
+ * @return Newly allocated lookup result object or NULL if an error occured.
+ */
+struct flnl_result *flnl_result_alloc(void)
+{
+ return (struct flnl_result *) nl_object_alloc_from_ops(&fib_lookup_ops);
+}
+
+/**
+ * Allocate lookup result cache.
+ *
+ * Allocates a new lookup result cache and initializes it properly.
+ *
+ * @note Free the memory after usage using nl_cache_destroy_and_free().
+ * @return Newly allocated cache or NULL if an error occured.
+ */
+struct nl_cache *flnl_result_alloc_cache(void)
+{
+ return nl_cache_alloc_from_ops(&fib_lookup_ops);
+}
+
+/**
+ * Give back reference on lookup result object.
+ * @arg res lookup result object to be given back.
+ *
+ * Decrements the reference counter and frees the object if the
+ * last reference has been released.
+ */
+void flnl_result_put(struct flnl_result *res)
+{
+ nl_object_put((struct nl_object *) res);
+}
+
+/**
+ * Free lookup result object.
+ * @arg res lookup result object to be freed.
+ *
+ * @note Always use flnl_result_put() unless you're absolutely sure
+ * that no other user may have a reference on this object.
+ */
+void flnl_result_free(struct flnl_result *res)
+{
+ nl_object_free((struct nl_object *) res);
+}
+
+/** @} */
+
+/**
+ * @name Lookup
+ * @{
+ */
+
+/**
+ * Builds a netlink request message to do a lookup
+ * @arg req Requested match.
+ * @arg flags additional netlink message flags
+ *
+ * Builds a new netlink message requesting a change of link attributes.
+ * The netlink message header isn't fully equipped with all relevant
+ * fields and must be sent out via nl_send_auto_complete() or
+ * supplemented as needed.
+ * \a old must point to a link currently configured in the kernel
+ * and \a tmpl must contain the attributes to be changed set via
+ * \c rtnl_link_set_* functions.
+ *
+ * @return New netlink message
+ * @note Not all attributes can be changed, see
+ * \ref link_changeable "Changeable Attributes" for more details.
+ */
+struct nl_msg *flnl_lookup_build_request(struct flnl_request *req, int flags)
+{
+ struct nl_msg *msg;
+ struct nl_addr *addr;
+ uint64_t fwmark;
+ int tos, scope, table;
+ struct fib_result_nl fr = {0};
+
+ fwmark = flnl_request_get_fwmark(req);
+ tos = flnl_request_get_tos(req);
+ scope = flnl_request_get_scope(req);
+ table = flnl_request_get_table(req);
+
+ fr.fl_fwmark = fwmark != UINT_LEAST64_MAX ? fwmark : 0;
+ fr.fl_tos = tos >= 0 ? tos : 0;
+ fr.fl_scope = scope >= 0 ? scope : RT_SCOPE_UNIVERSE;
+ fr.tb_id_in = table >= 0 ? table : RT_TABLE_UNSPEC;
+
+ addr = flnl_request_get_addr(req);
+ if (!addr) {
+ nl_error(EINVAL, "Request must specify the address");
+ return NULL;
+ }
+
+ fr.fl_addr = *(uint32_t *) nl_addr_get_binary_addr(addr);
+
+ msg = nlmsg_build_simple(0, flags);
+ if (!msg)
+ goto errout;
+
+ if (nlmsg_append(msg, &fr, sizeof(fr), 1) < 0)
+ goto errout;
+
+ return msg;
+
+errout:
+ nlmsg_free(msg);
+ return NULL;
+}
+
+/**
+ * Perform FIB Lookup
+ * @arg handle Netlink handle.
+ * @arg req Lookup request object.
+ * @arg cache Cache for result.
+ *
+ * Builds a netlink message to request a FIB lookup, waits for the
+ * reply and adds the result to the specified cache.
+ *
+ * @return 0 on success or a negative error code.
+ */
+int flnl_lookup(struct nl_handle *handle, struct flnl_request *req,
+ struct nl_cache *cache)
+{
+ struct nl_msg *msg;
+ int err;
+
+ msg = flnl_lookup_build_request(req, 0);
+ if (!msg)
+ return nl_errno(ENOMEM);
+
+ err = nl_send_auto_complete(handle, msg);
+ nlmsg_free(msg);
+ if (err < 0)
+ return err;
+
+ return nl_cache_pickup(handle, cache);
+}
+
+/** @} */
+
+/**
+ * @name Attribute Access
+ * @{
+ */
+
+int flnl_result_get_table_id(struct flnl_result *res)
+{
+ return res->fr_table_id;
+}
+
+int flnl_result_get_prefixlen(struct flnl_result *res)
+{
+ return res->fr_prefixlen;
+}
+
+int flnl_result_get_nexthop_sel(struct flnl_result *res)
+{
+ return res->fr_nh_sel;
+}
+
+int flnl_result_get_type(struct flnl_result *res)
+{
+ return res->fr_type;
+}
+
+int flnl_result_get_scope(struct flnl_result *res)
+{
+ return res->fr_scope;
+}
+
+int flnl_result_get_error(struct flnl_result *res)
+{
+ return res->fr_error;
+}
+
+/** @} */
+
+static struct nl_cache_ops fib_lookup_ops = {
+ .co_name = "fib_lookup/fib_lookup",
+ .co_size = sizeof(struct flnl_result),
+ .co_hdrsize = sizeof(struct fib_result_nl),
+ .co_msgtypes = {
+ { 0, "any" },
+ { -1, NULL },
+ },
+ .co_protocol = NETLINK_FIB_LOOKUP,
+ .co_msg_parser = result_msg_parser,
+ .co_free_data = result_free_data,
+ .co_dump[NL_DUMP_BRIEF] = result_dump_brief,
+ .co_dump[NL_DUMP_FULL] = result_dump_full,
+ .co_filter = result_filter,
+};
+
+static void __init fib_lookup_init(void)
+{
+ nl_cache_mngt_register(&fib_lookup_ops);
+}
+
+static void __exit fib_lookup_exit(void)
+{
+ nl_cache_mngt_unregister(&fib_lookup_ops);
+}
+
+/** @} */
git://git.onelab.eu / libnl.git / blobdiff