ip_dummynet.h

Go to the documentation of this file.

/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 1998-2010 Luigi Rizzo, Universita` di Pisa
 * Portions Copyright (c) 2000 Akamba Corp.
 * All rights reserved
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */
 
#ifndef _IP_DUMMYNET_H
#define _IP_DUMMYNET_H
#define NEW_AQM
/*
 * Definition of the kernel-userland API for dummynet.
 *
 * Setsockopt() and getsockopt() pass a batch of objects, each
 * of them starting with a "struct dn_id" which should fully identify
 * the object and its relation with others in the sequence.
 * The first object in each request should have
 *       type= DN_CMD_*, id = DN_API_VERSION.
 * For other objects, type and subtype specify the object, len indicates
 * the total length including the header, and 'id' identifies the specific
 * object.
 *
 * Most objects are numbered with an identifier in the range 1..65535.
 * DN_MAX_ID indicates the first value outside the range.
 */
 
#define DN_API_VERSION  12500000
#define DN_MAX_ID       0x10000
 
struct dn_id {
        uint16_t        len;    /* total obj len including this header */
        uint8_t         type;
        uint8_t         subtype;
        uint32_t        id;     /* generic id */
};
 
/*
 * These values are in the type field of struct dn_id.
 * To preserve the ABI, never rearrange the list or delete
 * entries with the exception of DN_LAST
 */
enum {
        DN_NONE = 0,
        DN_LINK = 1,
        DN_FS,
        DN_SCH,
        DN_SCH_I,
        DN_QUEUE,
        DN_DELAY_LINE,
        DN_PROFILE,
        DN_FLOW,                /* struct dn_flow */
        DN_TEXT,                /* opaque text is the object */
 
        DN_CMD_CONFIG = 0x80,   /* objects follow */
        DN_CMD_DELETE,          /* subtype + list of entries */
        DN_CMD_GET,             /* subtype + list of entries */
        DN_CMD_FLUSH,
        /* for compatibility with FreeBSD 7.2/8 */
        DN_COMPAT_PIPE,
        DN_COMPAT_QUEUE,
        DN_GET_COMPAT,
 
        /* special commands for emulation of sysctl variables */
        DN_SYSCTL_GET,
        DN_SYSCTL_SET,
#ifdef NEW_AQM
        /* subtypes used for setting/getting extra parameters.
         * these subtypes used with IP_DUMMYNET3 command (get)
         * and DN_TEXT (set). */
        DN_AQM_PARAMS, /* AQM extra params */
        DN_SCH_PARAMS, /* scheduler extra params */
#endif
        DN_LAST,
};
 
enum { /* subtype for schedulers, flowset and the like */
        DN_SCHED_UNKNOWN = 0,
        DN_SCHED_FIFO = 1,
        DN_SCHED_WF2QP = 2,
        /* others are in individual modules */
};
 
enum {  /* user flags */
        DN_HAVE_MASK    = 0x0001,       /* fs or sched has a mask */
        DN_NOERROR      = 0x0002,       /* do not report errors */
        DN_QHT_HASH     = 0x0004,       /* qht is a hash table */
        DN_QSIZE_BYTES  = 0x0008,       /* queue size is in bytes */
        DN_HAS_PROFILE  = 0x0010,       /* a link has a profile */
        DN_IS_RED       = 0x0020,
        DN_IS_GENTLE_RED= 0x0040,
        DN_IS_ECN       = 0x0080,
        #ifdef NEW_AQM
        DN_IS_AQM = 0x0100,     /* AQMs: e.g Codel & PIE */
        #endif
        DN_PIPE_CMD     = 0x1000,       /* pipe config... */
};
 
/*
 * link template.
 */
struct dn_link {
        struct dn_id oid;
 
        /*
         * Userland sets bw and delay in bits/s and milliseconds.
         * The kernel converts this back and forth to bits/tick and ticks.
         * XXX what about burst ?
         */
        int32_t         link_nr;
        uint32_t        bandwidth;      /* bit/s or bits/tick.   */
        int             delay;          /* ms and ticks */
        uint64_t        burst;          /* scaled. bits*Hz  XXX */
};
 
/*
 * A flowset, which is a template for flows. Contains parameters
 * from the command line: id, target scheduler, queue sizes, plr,
 * flow masks, buckets for the flow hash, and possibly scheduler-
 * specific parameters (weight, quantum and so on).
 */
struct dn_fs {
        struct dn_id oid;
        uint32_t fs_nr;         /* the flowset number */
        uint32_t flags;         /* userland flags */
        int qsize;              /* queue size in slots or bytes */
        int32_t plr;            /* PLR, pkt loss rate (2^31-1 means 100%) */
        uint32_t buckets;       /* buckets used for the queue hash table */
 
        struct ipfw_flow_id flow_mask;
        uint32_t sched_nr;      /* the scheduler we attach to */
        /* generic scheduler parameters. Leave them at -1 if unset.
         * Now we use 0: weight, 1: lmax, 2: priority
         */
        int par[4];
 
        /* RED/GRED parameters.
         * weight and probabilities are in the range 0..1 represented
         * in fixed point arithmetic with SCALE_RED decimal bits.
         */
#define SCALE_RED       16
#define SCALE(x)        ( (x) << SCALE_RED )
#define SCALE_VAL(x)    ( (x) >> SCALE_RED )
#define SCALE_MUL(x,y)  ( ( (x) * (y) ) >> SCALE_RED )
        int w_q ;               /* queue weight (scaled) */
        int max_th ;            /* maximum threshold for queue (scaled) */
        int min_th ;            /* minimum threshold for queue (scaled) */
        int max_p ;             /* maximum value for p_b (scaled) */
 
};
 
/*
 * dn_flow collects flow_id and stats for queues and scheduler
 * instances, and is used to pass these info to userland.
 * oid.type/oid.subtype describe the object, oid.id is number
 * of the parent object.
 */
struct dn_flow {
        struct dn_id    oid;
        struct ipfw_flow_id fid;
        uint64_t        tot_pkts; /* statistics counters  */
        uint64_t        tot_bytes;
        uint32_t        length; /* Queue length, in packets */
        uint32_t        len_bytes; /* Queue length, in bytes */
        uint32_t        drops;
};
 
/*
 * Scheduler template, mostly indicating the name, number,
 * sched_mask and buckets.
 */
struct dn_sch {
        struct dn_id    oid;
        uint32_t        sched_nr; /* N, scheduler number */
        uint32_t        buckets; /* number of buckets for the instances */
        uint32_t        flags;  /* have_mask, ... */
 
        char name[16];  /* null terminated */
        /* mask to select the appropriate scheduler instance */
        struct ipfw_flow_id sched_mask; /* M */
};
 
/* A delay profile is attached to a link.
 * Note that a profile, as any other object, cannot be longer than 2^16
 */
#define ED_MAX_SAMPLES_NO       1024
struct dn_profile {
        struct dn_id    oid;
        /* fields to simulate a delay profile */
#define ED_MAX_NAME_LEN         32
        char    name[ED_MAX_NAME_LEN];
        int     link_nr;
        int     loss_level;
        uint32_t        bandwidth;                      // XXX use link bandwidth?
        int     samples_no;                     /* actual len of samples[] */
        int     samples[ED_MAX_SAMPLES_NO];     /* may be shorter */
};
 
#ifdef NEW_AQM
/* Extra parameters for AQM and scheduler.
 * This struct is used to pass and retrieve parameters (configurations)
 * to/from AQM and Scheduler.
 */
struct dn_extra_parms {
        struct dn_id oid;
        char name[16];
        uint32_t nr;
#define DN_MAX_EXTRA_PARM       10
        int64_t par[DN_MAX_EXTRA_PARM];
};
#endif
 
/*
 * Overall structure of dummynet
 
In dummynet, packets are selected with the firewall rules, and passed
to two different objects: PIPE or QUEUE (bad name).
 
A QUEUE defines a classifier, which groups packets into flows
according to a 'mask', puts them into independent queues (one
per flow) with configurable size and queue management policy,
and passes flows to a scheduler:
 
                 (flow_mask|sched_mask)  sched_mask
         +---------+   weight Wx  +-------------+
         |         |->-[flow]-->--|             |-+
    -->--| QUEUE x |   ...        |             | |
         |         |->-[flow]-->--| SCHEDuler N | |
         +---------+              |             | |
             ...                  |             +--[LINK N]-->--
         +---------+   weight Wy  |             | +--[LINK N]-->--
         |         |->-[flow]-->--|             | |
    -->--| QUEUE y |   ...        |             | |
         |         |->-[flow]-->--|             | |
         +---------+              +-------------+ |
                                    +-------------+
 
Many QUEUE objects can connect to the same scheduler, each
QUEUE object can have its own set of parameters.
 
In turn, the SCHEDuler 'forks' multiple instances according
to a 'sched_mask', each instance manages its own set of queues
and transmits on a private instance of a configurable LINK.
 
A PIPE is a simplified version of the above, where there
is no flow_mask, and each scheduler instance handles a single queue.
 
The following data structures (visible from userland) describe
the objects used by dummynet:
 
 + dn_link, contains the main configuration parameters related
   to delay and bandwidth;
 + dn_profile describes a delay profile;
 + dn_flow describes the flow status (flow id, statistics)
 
 + dn_sch describes a scheduler
 + dn_fs describes a flowset (msk, weight, queue parameters)
 
 *
 */
 
#endif /* _IP_DUMMYNET_H */