/*
 * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef ODP_UTIL_H
#define ODP_UTIL_H 1

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include "flow.h"
#include "hash.h"
#include "openvswitch/hmap.h"
#include "openvswitch/ofp-actions.h"
#include "openvswitch/uuid.h"
#include "odp-netlink.h"
#include "openflow/openflow.h"
#include "util.h"

struct ds;
struct nlattr;
struct ofpbuf;
struct simap;
struct pkt_metadata;

#define SLOW_PATH_REASONS                                               \
    SPR(SLOW_CFM,        "cfm",        "Consists of CFM packets")       \
    SPR(SLOW_BFD,        "bfd",        "Consists of BFD packets")       \
    SPR(SLOW_LACP,       "lacp",       "Consists of LACP packets")      \
    SPR(SLOW_STP,        "stp",        "Consists of STP packets")       \
    SPR(SLOW_LLDP,       "lldp",       "Consists of LLDP packets")      \
    SPR(SLOW_ACTION,     "action",                                      \
        "Uses action(s) not supported by datapath")                     \
    SPR(SLOW_MATCH,      "match",                                       \
        "Datapath can't match specifically enough")

/* Indexes for slow-path reasons.  Client code uses "enum slow_path_reason"
 * values instead of these, these are just a way to construct those. */
enum {
#define SPR(ENUM, STRING, EXPLANATION) ENUM##_INDEX,
    SLOW_PATH_REASONS
#undef SPR
};

/* Reasons why a flow might not be fast-pathable.
 *
 * Each reason is a separate bit to allow reasons to be combined. */
enum slow_path_reason {
#define SPR(ENUM, STRING, EXPLANATION) ENUM = 1 << ENUM##_INDEX,
    SLOW_PATH_REASONS
#undef SPR
};

/* Mask of all slow_path_reasons. */
enum {
    SLOW_PATH_REASON_MASK = 0
#define SPR(ENUM, STRING, EXPLANATION) | 1 << ENUM##_INDEX 
    SLOW_PATH_REASONS
#undef SPR
};

const char *slow_path_reason_to_explanation(enum slow_path_reason);

#define ODPP_LOCAL ODP_PORT_C(OVSP_LOCAL)
#define ODPP_NONE  ODP_PORT_C(UINT32_MAX)

void format_odp_actions(struct ds *, const struct nlattr *odp_actions,
                        size_t actions_len, const struct hmap *portno_names);
int odp_actions_from_string(const char *, const struct simap *port_names,
                            struct ofpbuf *odp_actions);

/* A map from odp port number to its name. */
struct odp_portno_names {
    struct hmap_node hmap_node; /* A node in a port number to name hmap. */
    odp_port_t port_no;         /* Port number in the datapath. */
    char *name;                 /* Name associated with the above 'port_no'. */
};

void odp_portno_names_set(struct hmap *portno_names, odp_port_t port_no,
                          char *port_name);
void odp_portno_names_destroy(struct hmap *portno_names);
void odp_portno_name_format(const struct hmap *portno_names,
                            odp_port_t, struct ds *);

/* The maximum number of bytes that odp_flow_key_from_flow() appends to a
 * buffer.  This is the upper bound on the length of a nlattr-formatted flow
 * key that ovs-vswitchd fully understands.
 *
 * OVS doesn't insist that ovs-vswitchd and the datapath have exactly the same
 * idea of a flow, so therefore this value isn't necessarily an upper bound on
 * the length of a flow key that the datapath can pass to ovs-vswitchd.
 *
 * The longest nlattr-formatted flow key appended by odp_flow_key_from_flow()
 * would be:
 *
 *                                     struct  pad  nl hdr  total
 *                                     ------  ---  ------  -----
 *  OVS_KEY_ATTR_PRIORITY                4    --     4      8
 *  OVS_KEY_ATTR_TUNNEL                  0    --     4      4
 *  - OVS_TUNNEL_KEY_ATTR_ID             8    --     4     12
 *  - OVS_TUNNEL_KEY_ATTR_IPV4_SRC       4    --     4      8
 *  - OVS_TUNNEL_KEY_ATTR_IPV4_DST       4    --     4      8
 *  - OVS_TUNNEL_KEY_ATTR_IPV6_SRC       16   --     4     20
 *  - OVS_TUNNEL_KEY_ATTR_IPV6_DST       16   --     4     20
 *  - OVS_TUNNEL_KEY_ATTR_TOS            1    3      4      8
 *  - OVS_TUNNEL_KEY_ATTR_TTL            1    3      4      8
 *  - OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT  0    --     4      4
 *  - OVS_TUNNEL_KEY_ATTR_CSUM           0    --     4      4
 *  - OVS_TUNNEL_KEY_ATTR_OAM            0    --     4      4
 *  - OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS    256  --     4      260
 *  - OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS     -    --     -      - (shared with _GENEVE_OPTS)
 *  OVS_KEY_ATTR_IN_PORT                 4    --     4      8
 *  OVS_KEY_ATTR_SKB_MARK                4    --     4      8
 *  OVS_KEY_ATTR_DP_HASH                 4    --     4      8
 *  OVS_KEY_ATTR_RECIRC_ID               4    --     4      8
 *  OVS_KEY_ATTR_CT_STATE                4    --     4      8
 *  OVS_KEY_ATTR_CT_ZONE                 2     2     4      8
 *  OVS_KEY_ATTR_CT_MARK                 4    --     4      8
 *  OVS_KEY_ATTR_CT_LABEL               16    --     4     20
 *  OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6     40    --     4     44
 *  OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4      -    --     -      - (exclusive of_CT_ORIG_TUPLE_IPV6)
 *  OVS_KEY_ATTR_ETHERNET               12    --     4     16
 *  OVS_KEY_ATTR_ETHERTYPE               2     2     4      8  (outer VLAN ethertype)
 *  OVS_KEY_ATTR_VLAN                    2     2     4      8
 *  OVS_KEY_ATTR_ENCAP                   0    --     4      4  (VLAN encapsulation)
 *  OVS_KEY_ATTR_ETHERTYPE               2     2     4      8  (inner VLAN ethertype)
 *  OVS_KEY_ATTR_IPV6                   40    --     4     44
 *  OVS_KEY_ATTR_ICMPV6                  2     2     4      8
 *  OVS_KEY_ATTR_ND                     28    --     4     32
 *  ----------------------------------------------------------
 *  total                                                 616
 *
 * We include some slack space in case the calculation isn't quite right or we
 * add another field and forget to adjust this value.
 */
#define ODPUTIL_FLOW_KEY_BYTES 640
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 42);

/* A buffer with sufficient size and alignment to hold an nlattr-formatted flow
 * key.  An array of "struct nlattr" might not, in theory, be sufficiently
 * aligned because it only contains 16-bit types. */
struct odputil_keybuf {
    uint32_t keybuf[DIV_ROUND_UP(ODPUTIL_FLOW_KEY_BYTES, 4)];
};

enum odp_key_fitness odp_tun_key_from_attr(const struct nlattr *,
                                           struct flow_tnl *, char **errorp);
enum odp_key_fitness odp_nsh_key_from_attr(const struct nlattr *,
                                           struct ovs_key_nsh *,
                                           struct ovs_key_nsh *,
                                           char **errorp);
enum odp_key_fitness odp_nsh_hdr_from_attr(const struct nlattr *,
                                           struct nsh_hdr *, size_t);

int odp_ufid_from_string(const char *s_, ovs_u128 *ufid);
void odp_format_ufid(const ovs_u128 *ufid, struct ds *);

void odp_flow_format(const struct nlattr *key, size_t key_len,
                     const struct nlattr *mask, size_t mask_len,
                     const struct hmap *portno_names, struct ds *,
                     bool verbose);
void odp_flow_key_format(const struct nlattr *, size_t, struct ds *);
int odp_flow_from_string(const char *s, const struct simap *port_names,
                         struct ofpbuf *, struct ofpbuf *, char **errorp);

/* ODP_SUPPORT_FIELD(TYPE, FIELD_NAME, FIELD_DESCRIPTION)
 *
 * Each 'ODP_SUPPORT_FIELD' defines a member in 'struct odp_support',
 * and represents support for related OVS_KEY_ATTR_* fields.
 * They are defined as macros to keep 'dpif_show_support()' in sync
 * as new fields are added.   */
#define ODP_SUPPORT_FIELDS                                                   \
    /* Maximum number of 802.1q VLAN headers to serialize in a mask. */      \
    ODP_SUPPORT_FIELD(size_t, max_vlan_headers, "Max VLAN headers")          \
    /* Maximum number of MPLS label stack entries to serialise in a mask. */ \
    ODP_SUPPORT_FIELD(size_t, max_mpls_depth, "Max MPLS depth")              \
    /* If this is true, then recirculation fields will always be             \
     * serialised. */                                                        \
    ODP_SUPPORT_FIELD(bool, recirc, "Recirc")                                \
    /* If true, serialise the corresponding OVS_KEY_ATTR_CONN_* field. */    \
    ODP_SUPPORT_FIELD(bool, ct_state, "CT state")                            \
    ODP_SUPPORT_FIELD(bool, ct_zone, "CT zone")                              \
    ODP_SUPPORT_FIELD(bool, ct_mark, "CT mark")                              \
    ODP_SUPPORT_FIELD(bool, ct_label, "CT label")                            \
                                                                             \
    /* If true, it means that the datapath supports the NAT bits in          \
     * 'ct_state'.  The above 'ct_state' member must be true for this        \
     * to make sense */                                                      \
    ODP_SUPPORT_FIELD(bool, ct_state_nat, "CT state NAT")                    \
                                                                             \
    /* Conntrack original direction tuple matching * supported. */           \
    ODP_SUPPORT_FIELD(bool, ct_orig_tuple, "CT orig tuple")                  \
    ODP_SUPPORT_FIELD(bool, ct_orig_tuple6, "CT orig tuple for IPv6")        \
                                                                             \
    /* If true, it means that the datapath supports the IPv6 Neigh           \
     * Discovery Extension bits. */                                          \
    ODP_SUPPORT_FIELD(bool, nd_ext, "IPv6 ND Extension")

/* Indicates support for various fields. This defines how flows will be
 * serialised. */
struct odp_support {
#define ODP_SUPPORT_FIELD(TYPE, NAME, TITLE) TYPE NAME;
    ODP_SUPPORT_FIELDS
#undef ODP_SUPPORT_FIELD
};

struct odp_flow_key_parms {
    /* The flow and mask to be serialized. In the case of masks, 'flow'
     * is used as a template to determine how to interpret 'mask'.  For
     * example, the 'dl_type' of 'mask' describes the mask, but it doesn't
     * indicate whether the other fields should be interpreted as ARP, IPv4,
     * IPv6, etc. */
    const struct flow *flow;
    const struct flow *mask;

    /* Indicates support for various fields. If the datapath supports a field,
     * then it will always be serialised. */
    struct odp_support support;

    /* Indicates if we are probing datapath capability. If true, ignore the
     * configured flow limits. */
    bool probe;

    /* The netlink formatted version of the flow. It is used in cases where
     * the mask cannot be constructed from the OVS internal representation
     * and needs to see the original form. */
    const struct ofpbuf *key_buf;
};

void odp_flow_key_from_flow(const struct odp_flow_key_parms *, struct ofpbuf *);
void odp_flow_key_from_mask(const struct odp_flow_key_parms *, struct ofpbuf *);

void odp_flow_key_hash(const void *key, size_t key_len, ovs_u128 *hash);

/* Estimated space needed for metadata. */
enum { ODP_KEY_METADATA_SIZE = 9 * 8 };
void odp_key_from_dp_packet(struct ofpbuf *, const struct dp_packet *);
void odp_key_to_dp_packet(const struct nlattr *key, size_t key_len,
                          struct dp_packet *md);

/* How well a kernel-provided flow key (a sequence of OVS_KEY_ATTR_*
 * attributes) matches OVS userspace expectations.
 *
 * These values are arranged so that greater values are "more important" than
 * lesser ones.  In particular, a single flow key can fit the descriptions for
 * both ODP_FIT_TOO_LITTLE and ODP_FIT_TOO_MUCH.  Such a key is treated as
 * ODP_FIT_TOO_LITTLE. */
enum odp_key_fitness {
    ODP_FIT_PERFECT,            /* The key had exactly the fields we expect. */
    ODP_FIT_TOO_MUCH,           /* The key had fields we don't understand. */
    ODP_FIT_TOO_LITTLE,         /* The key lacked fields we expected to see. */
    ODP_FIT_ERROR,              /* The key was invalid. */
};
enum odp_key_fitness odp_flow_key_to_flow(const struct nlattr *, size_t,
                                          struct flow *, char **errorp);
enum odp_key_fitness odp_flow_key_to_mask(const struct nlattr *mask_key,
                                          size_t mask_key_len,
                                          struct flow_wildcards *mask,
                                          const struct flow *flow,
                                          char **errorp);
int parse_key_and_mask_to_match(const struct nlattr *key, size_t key_len,
                                const struct nlattr *mask, size_t mask_len,
                                struct match *match);

const char *odp_key_fitness_to_string(enum odp_key_fitness);

void commit_odp_tunnel_action(const struct flow *, struct flow *base,
                              struct ofpbuf *odp_actions,
                              const char *tnl_type);
void commit_masked_set_action(struct ofpbuf *odp_actions,
                              enum ovs_key_attr key_type, const void *key,
                              const void *mask, size_t key_size);
enum slow_path_reason commit_odp_actions(const struct flow *,
                                         struct flow *base,
                                         struct ofpbuf *odp_actions,
                                         struct flow_wildcards *wc,
                                         bool use_masked,
                                         bool pending_encap,
                                         bool pending_decap,
                                         struct ofpbuf *encap_data);

/* ofproto-dpif interface.
 *
 * The following types and functions are logically part of ofproto-dpif.
 * ofproto-dpif puts values of these types into the flows that it installs in
 * the kernel datapath, though, so ovs-dpctl needs to interpret them so that
 * it can print flows in a more human-readable manner. */

enum user_action_cookie_type {
    USER_ACTION_COOKIE_UNSPEC,
    USER_ACTION_COOKIE_SFLOW,        /* Packet for per-bridge sFlow sampling. */
    USER_ACTION_COOKIE_SLOW_PATH,    /* Userspace must process this flow. */
    USER_ACTION_COOKIE_FLOW_SAMPLE,  /* Packet for per-flow sampling. */
    USER_ACTION_COOKIE_IPFIX,        /* Packet for per-bridge IPFIX sampling. */
    USER_ACTION_COOKIE_CONTROLLER,   /* Forward packet to controller. */
};

/* user_action_cookie is passed as argument to OVS_ACTION_ATTR_USERSPACE. */
struct user_action_cookie {
    uint16_t type;              /* enum user_action_cookie_type. */
    ofp_port_t ofp_in_port;     /* OpenFlow in port, or OFPP_NONE. */
    struct uuid ofproto_uuid;   /* UUID of ofproto-dpif. */

    union {
        struct {
            /* USER_ACTION_COOKIE_SFLOW. */
            ovs_be16 vlan_tci;      /* Destination VLAN TCI. */
            uint32_t output;        /* SFL_FLOW_SAMPLE_TYPE 'output' value. */
        } sflow;

        struct {
            /* USER_ACTION_COOKIE_SLOW_PATH. */
            uint16_t unused;
            uint32_t reason;        /* enum slow_path_reason. */
        } slow_path;

        struct {
            /* USER_ACTION_COOKIE_FLOW_SAMPLE. */
            uint16_t probability;   /* Sampling probability. */
            uint32_t collector_set_id; /* ID of IPFIX collector set. */
            uint32_t obs_domain_id; /* Observation Domain ID. */
            uint32_t obs_point_id;  /* Observation Point ID. */
            odp_port_t output_odp_port; /* The output odp port. */
            enum nx_action_sample_direction direction;
        } flow_sample;

        struct {
            /* USER_ACTION_COOKIE_IPFIX. */
            odp_port_t output_odp_port; /* The output odp port. */
        } ipfix;

        struct {
            /* USER_ACTION_COOKIE_CONTROLLER. */
            uint8_t dont_send;      /* Don't send the packet to controller. */
            uint8_t continuation;   /* Send packet-in as a continuation. */
            uint16_t reason;
            uint32_t recirc_id;
            ovs_32aligned_be64 rule_cookie;
            uint16_t controller_id;
            uint16_t max_len;
        } controller;
    };
};
BUILD_ASSERT_DECL(sizeof(struct user_action_cookie) == 48);

int odp_put_userspace_action(uint32_t pid,
                             const void *userdata, size_t userdata_size,
                             odp_port_t tunnel_out_port,
                             bool include_actions,
                             struct ofpbuf *odp_actions,
                             size_t *odp_actions_ofs);
void odp_put_tunnel_action(const struct flow_tnl *tunnel,
                           struct ofpbuf *odp_actions,
                           const char *tnl_type);

void odp_put_tnl_push_action(struct ofpbuf *odp_actions,
                             struct ovs_action_push_tnl *data);

void odp_put_pop_eth_action(struct ofpbuf *odp_actions);
void odp_put_push_eth_action(struct ofpbuf *odp_actions,
                             const struct eth_addr *eth_src,
                             const struct eth_addr *eth_dst);

struct attr_len_tbl {
    int len;
    const struct attr_len_tbl *next;
    int next_max;
};

#define ATTR_LEN_INVALID  -1
#define ATTR_LEN_VARIABLE -2
#define ATTR_LEN_NESTED   -3

extern const struct attr_len_tbl ovs_flow_key_attr_lens[OVS_KEY_ATTR_MAX + 1];
#endif /* odp-util.h */
