--- /dev/null
+/*
+ * net/sched/em_meta.c Metadata ematch
+ *
+ * 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: Thomas Graf <tgraf@suug.ch>
+ *
+ * ==========================================================================
+ *
+ * The metadata ematch compares two meta objects where each object
+ * represents either a meta value stored in the kernel or a static
+ * value provided by userspace. The objects are not provided by
+ * userspace itself but rather a definition providing the information
+ * to build them. Every object is of a certain type which must be
+ * equal to the object it is being compared to.
+ *
+ * The definition of a objects conists of the type (meta type), a
+ * identifier (meta id) and additional type specific information.
+ * The meta id is either TCF_META_TYPE_VALUE for values provided by
+ * userspace or a index to the meta operations table consisting of
+ * function pointers to type specific meta data collectors returning
+ * the value of the requested meta value.
+ *
+ * lvalue rvalue
+ * +-----------+ +-----------+
+ * | type: INT | | type: INT |
+ * def | id: INDEV | | id: VALUE |
+ * | data: | | data: 3 |
+ * +-----------+ +-----------+
+ * | |
+ * ---> meta_ops[INT][INDEV](...) |
+ * | |
+ * ----------- |
+ * V V
+ * +-----------+ +-----------+
+ * | type: INT | | type: INT |
+ * obj | id: INDEV | | id: VALUE |
+ * | data: 2 |<--data got filled out | data: 3 |
+ * +-----------+ +-----------+
+ * | |
+ * --------------> 2 equals 3 <--------------
+ *
+ * This is a simplified schema, the complexity varies depending
+ * on the meta type. Obviously, the length of the data must also
+ * be provided for non-numeric types.
+ *
+ * Additionaly, type dependant modifiers such as shift operators
+ * or mask may be applied to extend the functionaliy. As of now,
+ * the variable length type supports shifting the byte string to
+ * the right, eating up any number of octets and thus supporting
+ * wildcard interface name comparisons such as "ppp%" matching
+ * ppp0..9.
+ *
+ * NOTE: Certain meta values depend on other subsystems and are
+ * only available if that subsytem is enabled in the kernel.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/random.h>
+#include <linux/tc_ematch/tc_em_meta.h>
+#include <net/dst.h>
+#include <net/route.h>
+#include <net/pkt_cls.h>
+#include <net/sock.h>
+
+struct meta_obj
+{
+ unsigned long value;
+ unsigned int len;
+};
+
+struct meta_value
+{
+ struct tcf_meta_val hdr;
+ unsigned long val;
+ unsigned int len;
+};
+
+struct meta_match
+{
+ struct meta_value lvalue;
+ struct meta_value rvalue;
+};
+
+static inline int meta_id(struct meta_value *v)
+{
+ return TCF_META_ID(v->hdr.kind);
+}
+
+static inline int meta_type(struct meta_value *v)
+{
+ return TCF_META_TYPE(v->hdr.kind);
+}
+
+#define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
+ struct tcf_pkt_info *info, struct meta_value *v, \
+ struct meta_obj *dst, int *err)
+
+/**************************************************************************
+ * System status & misc
+ **************************************************************************/
+
+META_COLLECTOR(int_random)
+{
+ get_random_bytes(&dst->value, sizeof(dst->value));
+}
+
+static inline unsigned long fixed_loadavg(int load)
+{
+ int rnd_load = load + (FIXED_1/200);
+ int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
+
+ return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
+}
+
+META_COLLECTOR(int_loadavg_0)
+{
+ dst->value = fixed_loadavg(avenrun[0]);
+}
+
+META_COLLECTOR(int_loadavg_1)
+{
+ dst->value = fixed_loadavg(avenrun[1]);
+}
+
+META_COLLECTOR(int_loadavg_2)
+{
+ dst->value = fixed_loadavg(avenrun[2]);
+}
+
+/**************************************************************************
+ * Device names & indices
+ **************************************************************************/
+
+static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
+{
+ if (unlikely(dev == NULL))
+ return -1;
+
+ dst->value = dev->ifindex;
+ return 0;
+}
+
+static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
+{
+ if (unlikely(dev == NULL))
+ return -1;
+
+ dst->value = (unsigned long) dev->name;
+ dst->len = strlen(dev->name);
+ return 0;
+}
+
+META_COLLECTOR(int_dev)
+{
+ *err = int_dev(skb->dev, dst);
+}
+
+META_COLLECTOR(var_dev)
+{
+ *err = var_dev(skb->dev, dst);
+}
+
+META_COLLECTOR(int_indev)
+{
+ *err = int_dev(skb->input_dev, dst);
+}
+
+META_COLLECTOR(var_indev)
+{
+ *err = var_dev(skb->input_dev, dst);
+}
+
+META_COLLECTOR(int_realdev)
+{
+ *err = int_dev(skb->real_dev, dst);
+}
+
+META_COLLECTOR(var_realdev)
+{
+ *err = var_dev(skb->real_dev, dst);
+}
+
+/**************************************************************************
+ * skb attributes
+ **************************************************************************/
+
+META_COLLECTOR(int_priority)
+{
+ dst->value = skb->priority;
+}
+
+META_COLLECTOR(int_protocol)
+{
+ /* Let userspace take care of the byte ordering */
+ dst->value = skb->protocol;
+}
+
+META_COLLECTOR(int_security)
+{
+ dst->value = skb->security;
+}
+
+META_COLLECTOR(int_pkttype)
+{
+ dst->value = skb->pkt_type;
+}
+
+META_COLLECTOR(int_pktlen)
+{
+ dst->value = skb->len;
+}
+
+META_COLLECTOR(int_datalen)
+{
+ dst->value = skb->data_len;
+}
+
+META_COLLECTOR(int_maclen)
+{
+ dst->value = skb->mac_len;
+}
+
+/**************************************************************************
+ * Netfilter
+ **************************************************************************/
+
+#ifdef CONFIG_NETFILTER
+META_COLLECTOR(int_nfmark)
+{
+ dst->value = skb->nfmark;
+}
+#endif
+
+/**************************************************************************
+ * Traffic Control
+ **************************************************************************/
+
+META_COLLECTOR(int_tcindex)
+{
+ dst->value = skb->tc_index;
+}
+
+#ifdef CONFIG_NET_CLS_ACT
+META_COLLECTOR(int_tcverd)
+{
+ dst->value = skb->tc_verd;
+}
+
+META_COLLECTOR(int_tcclassid)
+{
+ dst->value = skb->tc_classid;
+}
+#endif
+
+/**************************************************************************
+ * Routing
+ **************************************************************************/
+
+#ifdef CONFIG_NET_CLS_ROUTE
+META_COLLECTOR(int_rtclassid)
+{
+ if (unlikely(skb->dst == NULL))
+ *err = -1;
+ else
+ dst->value = skb->dst->tclassid;
+}
+#endif
+
+META_COLLECTOR(int_rtiif)
+{
+ if (unlikely(skb->dst == NULL))
+ *err = -1;
+ else
+ dst->value = ((struct rtable*) skb->dst)->fl.iif;
+}
+
+/**************************************************************************
+ * Socket Attributes
+ **************************************************************************/
+
+#define SKIP_NONLOCAL(skb) \
+ if (unlikely(skb->sk == NULL)) { \
+ *err = -1; \
+ return; \
+ }
+
+META_COLLECTOR(int_sk_family)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_family;
+}
+
+META_COLLECTOR(int_sk_state)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_state;
+}
+
+META_COLLECTOR(int_sk_reuse)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_reuse;
+}
+
+META_COLLECTOR(int_sk_bound_if)
+{
+ SKIP_NONLOCAL(skb);
+ /* No error if bound_dev_if is 0, legal userspace check */
+ dst->value = skb->sk->sk_bound_dev_if;
+}
+
+META_COLLECTOR(var_sk_bound_if)
+{
+ SKIP_NONLOCAL(skb);
+
+ if (skb->sk->sk_bound_dev_if == 0) {
+ dst->value = (unsigned long) "any";
+ dst->len = 3;
+ } else {
+ struct net_device *dev;
+
+ dev = dev_get_by_index(skb->sk->sk_bound_dev_if);
+ *err = var_dev(dev, dst);
+ if (dev)
+ dev_put(dev);
+ }
+}
+
+META_COLLECTOR(int_sk_refcnt)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = atomic_read(&skb->sk->sk_refcnt);
+}
+
+META_COLLECTOR(int_sk_rcvbuf)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_rcvbuf;
+}
+
+META_COLLECTOR(int_sk_shutdown)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_shutdown;
+}
+
+META_COLLECTOR(int_sk_proto)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_protocol;
+}
+
+META_COLLECTOR(int_sk_type)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_type;
+}
+
+META_COLLECTOR(int_sk_rmem_alloc)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = atomic_read(&skb->sk->sk_rmem_alloc);
+}
+
+META_COLLECTOR(int_sk_wmem_alloc)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = atomic_read(&skb->sk->sk_wmem_alloc);
+}
+
+META_COLLECTOR(int_sk_omem_alloc)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = atomic_read(&skb->sk->sk_omem_alloc);
+}
+
+META_COLLECTOR(int_sk_rcv_qlen)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_receive_queue.qlen;
+}
+
+META_COLLECTOR(int_sk_snd_qlen)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_write_queue.qlen;
+}
+
+META_COLLECTOR(int_sk_wmem_queued)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_wmem_queued;
+}
+
+META_COLLECTOR(int_sk_fwd_alloc)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_forward_alloc;
+}
+
+META_COLLECTOR(int_sk_sndbuf)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_sndbuf;
+}
+
+META_COLLECTOR(int_sk_alloc)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_allocation;
+}
+
+META_COLLECTOR(int_sk_route_caps)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_route_caps;
+}
+
+META_COLLECTOR(int_sk_hashent)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_hashent;
+}
+
+META_COLLECTOR(int_sk_lingertime)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_lingertime / HZ;
+}
+
+META_COLLECTOR(int_sk_err_qlen)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_error_queue.qlen;
+}
+
+META_COLLECTOR(int_sk_ack_bl)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_ack_backlog;
+}
+
+META_COLLECTOR(int_sk_max_ack_bl)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_max_ack_backlog;
+}
+
+META_COLLECTOR(int_sk_prio)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_priority;
+}
+
+META_COLLECTOR(int_sk_rcvlowat)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_rcvlowat;
+}
+
+META_COLLECTOR(int_sk_rcvtimeo)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_rcvtimeo / HZ;
+}
+
+META_COLLECTOR(int_sk_sndtimeo)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_sndtimeo / HZ;
+}
+
+META_COLLECTOR(int_sk_sendmsg_off)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_sndmsg_off;
+}
+
+META_COLLECTOR(int_sk_write_pend)
+{
+ SKIP_NONLOCAL(skb);
+ dst->value = skb->sk->sk_write_pending;
+}
+
+/**************************************************************************
+ * Meta value collectors assignment table
+ **************************************************************************/
+
+struct meta_ops
+{
+ void (*get)(struct sk_buff *, struct tcf_pkt_info *,
+ struct meta_value *, struct meta_obj *, int *);
+};
+
+#define META_ID(name) TCF_META_ID_##name
+#define META_FUNC(name) { .get = meta_##name }
+
+/* Meta value operations table listing all meta value collectors and
+ * assigns them to a type and meta id. */
+static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = {
+ [TCF_META_TYPE_VAR] = {
+ [META_ID(DEV)] = META_FUNC(var_dev),
+ [META_ID(INDEV)] = META_FUNC(var_indev),
+ [META_ID(REALDEV)] = META_FUNC(var_realdev),
+ [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if),
+ },
+ [TCF_META_TYPE_INT] = {
+ [META_ID(RANDOM)] = META_FUNC(int_random),
+ [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0),
+ [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1),
+ [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2),
+ [META_ID(DEV)] = META_FUNC(int_dev),
+ [META_ID(INDEV)] = META_FUNC(int_indev),
+ [META_ID(REALDEV)] = META_FUNC(int_realdev),
+ [META_ID(PRIORITY)] = META_FUNC(int_priority),
+ [META_ID(PROTOCOL)] = META_FUNC(int_protocol),
+ [META_ID(SECURITY)] = META_FUNC(int_security),
+ [META_ID(PKTTYPE)] = META_FUNC(int_pkttype),
+ [META_ID(PKTLEN)] = META_FUNC(int_pktlen),
+ [META_ID(DATALEN)] = META_FUNC(int_datalen),
+ [META_ID(MACLEN)] = META_FUNC(int_maclen),
+#ifdef CONFIG_NETFILTER
+ [META_ID(NFMARK)] = META_FUNC(int_nfmark),
+#endif
+ [META_ID(TCINDEX)] = META_FUNC(int_tcindex),
+#ifdef CONFIG_NET_CLS_ACT
+ [META_ID(TCVERDICT)] = META_FUNC(int_tcverd),
+ [META_ID(TCCLASSID)] = META_FUNC(int_tcclassid),
+#endif
+#ifdef CONFIG_NET_CLS_ROUTE
+ [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid),
+#endif
+ [META_ID(RTIIF)] = META_FUNC(int_rtiif),
+ [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family),
+ [META_ID(SK_STATE)] = META_FUNC(int_sk_state),
+ [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse),
+ [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if),
+ [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt),
+ [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf),
+ [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf),
+ [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown),
+ [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto),
+ [META_ID(SK_TYPE)] = META_FUNC(int_sk_type),
+ [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc),
+ [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc),
+ [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc),
+ [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued),
+ [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen),
+ [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen),
+ [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen),
+ [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc),
+ [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc),
+ [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps),
+ [META_ID(SK_HASHENT)] = META_FUNC(int_sk_hashent),
+ [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime),
+ [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl),
+ [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl),
+ [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio),
+ [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat),
+ [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo),
+ [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo),
+ [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off),
+ [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend),
+ }
+};
+
+static inline struct meta_ops * meta_ops(struct meta_value *val)
+{
+ return &__meta_ops[meta_type(val)][meta_id(val)];
+}
+
+/**************************************************************************
+ * Type specific operations for TCF_META_TYPE_VAR
+ **************************************************************************/
+
+static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
+{
+ int r = a->len - b->len;
+
+ if (r == 0)
+ r = memcmp((void *) a->value, (void *) b->value, a->len);
+
+ return r;
+}
+
+static int meta_var_change(struct meta_value *dst, struct rtattr *rta)
+{
+ int len = RTA_PAYLOAD(rta);
+
+ dst->val = (unsigned long) kmalloc(len, GFP_KERNEL);
+ if (dst->val == 0UL)
+ return -ENOMEM;
+ memcpy((void *) dst->val, RTA_DATA(rta), len);
+ dst->len = len;
+ return 0;
+}
+
+static void meta_var_destroy(struct meta_value *v)
+{
+ if (v->val)
+ kfree((void *) v->val);
+}
+
+static void meta_var_apply_extras(struct meta_value *v,
+ struct meta_obj *dst)
+{
+ int shift = v->hdr.shift;
+
+ if (shift && shift < dst->len)
+ dst->len -= shift;
+}
+
+static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
+{
+ if (v->val && v->len)
+ RTA_PUT(skb, tlv, v->len, (void *) v->val);
+ return 0;
+
+rtattr_failure:
+ return -1;
+}
+
+/**************************************************************************
+ * Type specific operations for TCF_META_TYPE_INT
+ **************************************************************************/
+
+static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
+{
+ /* Let gcc optimize it, the unlikely is not really based on
+ * some numbers but jump free code for mismatches seems
+ * more logical. */
+ if (unlikely(a->value == b->value))
+ return 0;
+ else if (a->value < b->value)
+ return -1;
+ else
+ return 1;
+}
+
+static int meta_int_change(struct meta_value *dst, struct rtattr *rta)
+{
+ if (RTA_PAYLOAD(rta) >= sizeof(unsigned long)) {
+ dst->val = *(unsigned long *) RTA_DATA(rta);
+ dst->len = sizeof(unsigned long);
+ } else if (RTA_PAYLOAD(rta) == sizeof(u32)) {
+ dst->val = *(u32 *) RTA_DATA(rta);
+ dst->len = sizeof(u32);
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+
+static void meta_int_apply_extras(struct meta_value *v,
+ struct meta_obj *dst)
+{
+ if (v->hdr.shift)
+ dst->value >>= v->hdr.shift;
+
+ if (v->val)
+ dst->value &= v->val;
+}
+
+static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
+{
+ if (v->len == sizeof(unsigned long))
+ RTA_PUT(skb, tlv, sizeof(unsigned long), &v->val);
+ else if (v->len == sizeof(u32)) {
+ u32 d = v->val;
+ RTA_PUT(skb, tlv, sizeof(d), &d);
+ }
+
+ return 0;
+
+rtattr_failure:
+ return -1;
+}
+
+/**************************************************************************
+ * Type specific operations table
+ **************************************************************************/
+
+struct meta_type_ops
+{
+ void (*destroy)(struct meta_value *);
+ int (*compare)(struct meta_obj *, struct meta_obj *);
+ int (*change)(struct meta_value *, struct rtattr *);
+ void (*apply_extras)(struct meta_value *, struct meta_obj *);
+ int (*dump)(struct sk_buff *, struct meta_value *, int);
+};
+
+static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = {
+ [TCF_META_TYPE_VAR] = {
+ .destroy = meta_var_destroy,
+ .compare = meta_var_compare,
+ .change = meta_var_change,
+ .apply_extras = meta_var_apply_extras,
+ .dump = meta_var_dump
+ },
+ [TCF_META_TYPE_INT] = {
+ .compare = meta_int_compare,
+ .change = meta_int_change,
+ .apply_extras = meta_int_apply_extras,
+ .dump = meta_int_dump
+ }
+};
+
+static inline struct meta_type_ops * meta_type_ops(struct meta_value *v)
+{
+ return &__meta_type_ops[meta_type(v)];
+}
+
+/**************************************************************************
+ * Core
+ **************************************************************************/
+
+static inline int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
+ struct meta_value *v, struct meta_obj *dst)
+{
+ int err = 0;
+
+ if (meta_id(v) == TCF_META_ID_VALUE) {
+ dst->value = v->val;
+ dst->len = v->len;
+ return 0;
+ }
+
+ meta_ops(v)->get(skb, info, v, dst, &err);
+ if (err < 0)
+ return err;
+
+ if (meta_type_ops(v)->apply_extras)
+ meta_type_ops(v)->apply_extras(v, dst);
+
+ return 0;
+}
+
+static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
+ struct tcf_pkt_info *info)
+{
+ int r;
+ struct meta_match *meta = (struct meta_match *) m->data;
+ struct meta_obj l_value, r_value;
+
+ if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
+ meta_get(skb, info, &meta->rvalue, &r_value) < 0)
+ return 0;
+
+ r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
+
+ switch (meta->lvalue.hdr.op) {
+ case TCF_EM_OPND_EQ:
+ return !r;
+ case TCF_EM_OPND_LT:
+ return r < 0;
+ case TCF_EM_OPND_GT:
+ return r > 0;
+ }
+
+ return 0;
+}
+
+static inline void meta_delete(struct meta_match *meta)
+{
+ struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
+
+ if (ops && ops->destroy) {
+ ops->destroy(&meta->lvalue);
+ ops->destroy(&meta->rvalue);
+ }
+
+ kfree(meta);
+}
+
+static inline int meta_change_data(struct meta_value *dst, struct rtattr *rta)
+{
+ if (rta) {
+ if (RTA_PAYLOAD(rta) == 0)
+ return -EINVAL;
+
+ return meta_type_ops(dst)->change(dst, rta);
+ }
+
+ return 0;
+}
+
+static inline int meta_is_supported(struct meta_value *val)
+{
+ return (!meta_id(val) || meta_ops(val)->get);
+}
+
+static int em_meta_change(struct tcf_proto *tp, void *data, int len,
+ struct tcf_ematch *m)
+{
+ int err = -EINVAL;
+ struct rtattr *tb[TCA_EM_META_MAX];
+ struct tcf_meta_hdr *hdr;
+ struct meta_match *meta = NULL;
+
+ if (rtattr_parse(tb, TCA_EM_META_MAX, data, len) < 0)
+ goto errout;
+
+ if (tb[TCA_EM_META_HDR-1] == NULL ||
+ RTA_PAYLOAD(tb[TCA_EM_META_HDR-1]) < sizeof(*hdr))
+ goto errout;
+ hdr = RTA_DATA(tb[TCA_EM_META_HDR-1]);
+
+ if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
+ TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
+ TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
+ TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
+ goto errout;
+
+ meta = kmalloc(sizeof(*meta), GFP_KERNEL);
+ if (meta == NULL)
+ goto errout;
+ memset(meta, 0, sizeof(*meta));
+
+ memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
+ memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
+
+ if (!meta_is_supported(&meta->lvalue) ||
+ !meta_is_supported(&meta->rvalue)) {
+ err = -EOPNOTSUPP;
+ goto errout;
+ }
+
+ if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE-1]) < 0 ||
+ meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE-1]) < 0)
+ goto errout;
+
+ m->datalen = sizeof(*meta);
+ m->data = (unsigned long) meta;
+
+ err = 0;
+errout:
+ if (err && meta)
+ meta_delete(meta);
+ return err;
+}
+
+static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
+{
+ if (m)
+ meta_delete((struct meta_match *) m->data);
+}
+
+static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
+{
+ struct meta_match *meta = (struct meta_match *) em->data;
+ struct tcf_meta_hdr hdr;
+ struct meta_type_ops *ops;
+
+ memset(&hdr, 0, sizeof(hdr));
+ memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
+ memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
+
+ RTA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr);
+
+ ops = meta_type_ops(&meta->lvalue);
+ if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
+ ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
+ goto rtattr_failure;
+
+ return 0;
+
+rtattr_failure:
+ return -1;
+}
+
+static struct tcf_ematch_ops em_meta_ops = {
+ .kind = TCF_EM_META,
+ .change = em_meta_change,
+ .match = em_meta_match,
+ .destroy = em_meta_destroy,
+ .dump = em_meta_dump,
+ .owner = THIS_MODULE,
+ .link = LIST_HEAD_INIT(em_meta_ops.link)
+};
+
+static int __init init_em_meta(void)
+{
+ return tcf_em_register(&em_meta_ops);
+}
+
+static void __exit exit_em_meta(void)
+{
+ tcf_em_unregister(&em_meta_ops);
+}
+
+MODULE_LICENSE("GPL");
+
+module_init(init_em_meta);
+module_exit(exit_em_meta);
git://git.onelab.eu / linux-2.6.git / blobdiff