/src/frr/zebra/tc_netlink.c

Source
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Zebra Traffic Control (TC) interaction with the kernel using netlink.
 *
 * Copyright (C) 2022 Shichu Yang
 */

#include <zebra.h>

#ifdef HAVE_NETLINK

#include <linux/pkt_cls.h>
#include <linux/pkt_sched.h>
#include <netinet/if_ether.h>
#include <sys/socket.h>

#include "if.h"
#include "prefix.h"
#include "vrf.h"

#include "zebra/zserv.h"
#include "zebra/zebra_ns.h"
#include "zebra/rt.h"
#include "zebra/interface.h"
#include "zebra/debug.h"
#include "zebra/kernel_netlink.h"
#include "zebra/tc_netlink.h"
#include "zebra/zebra_errors.h"
#include "zebra/zebra_dplane.h"
#include "zebra/zebra_tc.h"
#include "zebra/zebra_trace.h"

#define TC_FREQ_DEFAULT (100)

/* some magic number */
#define TC_QDISC_MAJOR_ZEBRA (0xbeef0000u)
#define TC_MINOR_NOCLASS (0xffffu)

#define TIME_UNITS_PER_SEC (1000000)
#define xmittime(r, s) (TIME_UNITS_PER_SEC * ((double)(s) / (double)(r)))

static uint32_t tc_get_freq(void)
{
  int freq = 0;
  FILE *fp = fopen("/proc/net/psched", "r");

  if (fp) {
    uint32_t nom, denom;

    if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2) {
      if (nom == 1000000)
        freq = denom;
    }
    fclose(fp);
  }

  return freq == 0 ? TC_FREQ_DEFAULT : freq;
}

static void tc_calc_rate_table(struct tc_ratespec *ratespec, uint32_t *table,
             uint32_t mtu)
{
  if (mtu == 0)
    mtu = 2047;

  int cell_log = -1;

  if (cell_log < 0) {
    cell_log = 0;
    while ((mtu >> cell_log) > 255)
      cell_log++;
  }

  for (int i = 0; i < 256; i++)
    table[i] = xmittime(ratespec->rate, (i + 1) << cell_log);

  ratespec->cell_align = -1;
  ratespec->cell_log = cell_log;
  ratespec->linklayer = TC_LINKLAYER_ETHERNET;
}

static int tc_flower_get_inet_prefix(const struct prefix *prefix,
             struct inet_prefix *addr)
{
  addr->family = prefix->family;

  if (addr->family == AF_INET) {
    addr->bytelen = 4;
    addr->bitlen = prefix->prefixlen;
    addr->flags = 0;
    addr->flags |= PREFIXLEN_SPECIFIED;
    addr->flags |= ADDRTYPE_INET;
    memcpy(addr->data, prefix->u.val32, sizeof(prefix->u.val32));
  } else if (addr->family == AF_INET6) {
    addr->bytelen = 16;
    addr->bitlen = prefix->prefixlen;
    addr->flags = 0;
    addr->flags |= PREFIXLEN_SPECIFIED;
    addr->flags |= ADDRTYPE_INET;
    memcpy(addr->data, prefix->u.val, sizeof(prefix->u.val));
  } else {
    return -1;
  }

  return 0;
}

static int tc_flower_get_inet_mask(const struct prefix *prefix,
           struct inet_prefix *addr)
{
  addr->family = prefix->family;

  if (addr->family == AF_INET) {
    addr->bytelen = 4;
    addr->bitlen = prefix->prefixlen;
    addr->flags = 0;
    addr->flags |= PREFIXLEN_SPECIFIED;
    addr->flags |= ADDRTYPE_INET;
  } else if (addr->family == AF_INET6) {
    addr->bytelen = 16;
    addr->bitlen = prefix->prefixlen;
    addr->flags = 0;
    addr->flags |= PREFIXLEN_SPECIFIED;
    addr->flags |= ADDRTYPE_INET;
  } else {
    return -1;
  }

  memset(addr->data, 0xff, addr->bytelen);

  int rest = prefix->prefixlen;

  for (int i = 0; i < addr->bytelen / 4; i++) {
    if (!rest) {
      addr->data[i] = 0;
    } else if (rest / 32 >= 1) {
      rest -= 32;
    } else {
      addr->data[i] <<= 32 - rest;
      addr->data[i] = htonl(addr->data[i]);
      rest = 0;
    }
  }

  return 0;
}

/*
 * Traffic control queue discipline encoding (only "htb" supported)
 */
static ssize_t netlink_qdisc_msg_encode(int cmd, struct zebra_dplane_ctx *ctx,
          void *data, size_t datalen)
{
  struct nlsock *nl;
  const char *kind_str = NULL;

  struct rtattr *nest;

  struct {
    struct nlmsghdr n;
    struct tcmsg t;
    char buf[0];
  } *req = (void *)data;

  if (datalen < sizeof(*req))
    return 0;

  nl = kernel_netlink_nlsock_lookup(dplane_ctx_get_ns_sock(ctx));

  memset(req, 0, sizeof(*req));

  req->n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  req->n.nlmsg_flags = NLM_F_CREATE | NLM_F_REQUEST;

  req->n.nlmsg_flags |= NLM_F_REPLACE;

  req->n.nlmsg_type = cmd;

  req->n.nlmsg_pid = nl->snl.nl_pid;

  req->t.tcm_family = AF_UNSPEC;
  req->t.tcm_ifindex = dplane_ctx_get_ifindex(ctx);
  req->t.tcm_info = 0;
  req->t.tcm_handle = 0;
  req->t.tcm_parent = TC_H_ROOT;

  if (cmd == RTM_NEWQDISC) {
    req->t.tcm_handle = TC_H_MAKE(TC_QDISC_MAJOR_ZEBRA, 0);

    kind_str = dplane_ctx_tc_qdisc_get_kind_str(ctx);

    nl_attr_put(&req->n, datalen, TCA_KIND, kind_str,
          strlen(kind_str) + 1);

    nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS);

    switch (dplane_ctx_tc_qdisc_get_kind(ctx)) {
    case TC_QDISC_HTB: {
      struct tc_htb_glob htb_glob = {
        .rate2quantum = 10,
        .version = 3,
        .defcls = TC_MINOR_NOCLASS};
      nl_attr_put(&req->n, datalen, TCA_HTB_INIT, &htb_glob,
            sizeof(htb_glob));
      break;
    }
    case TC_QDISC_NOQUEUE:
      break;
    default:
      break;
      /* not implemented */
    }

    nl_attr_nest_end(&req->n, nest);
  } else {
    /* ifindex are enough for del/get qdisc */
  }

  return NLMSG_ALIGN(req->n.nlmsg_len);
}

/*
 * Traffic control class encoding
 */
static ssize_t netlink_tclass_msg_encode(int cmd, struct zebra_dplane_ctx *ctx,
           void *data, size_t datalen)
{
  enum dplane_op_e op = dplane_ctx_get_op(ctx);

  struct nlsock *nl;
  const char *kind_str = NULL;

  struct rtattr *nest;

  struct {
    struct nlmsghdr n;
    struct tcmsg t;
    char buf[0];
  } *req = (void *)data;

  if (datalen < sizeof(*req))
    return 0;

  nl = kernel_netlink_nlsock_lookup(dplane_ctx_get_ns_sock(ctx));

  memset(req, 0, sizeof(*req));

  req->n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  req->n.nlmsg_flags = NLM_F_CREATE | NLM_F_REQUEST;

  if (op == DPLANE_OP_TC_CLASS_UPDATE)
    req->n.nlmsg_flags |= NLM_F_REPLACE;

  req->n.nlmsg_type = cmd;

  req->n.nlmsg_pid = nl->snl.nl_pid;

  req->t.tcm_family = AF_UNSPEC;
  req->t.tcm_ifindex = dplane_ctx_get_ifindex(ctx);

  req->t.tcm_handle = TC_H_MAKE(TC_QDISC_MAJOR_ZEBRA,
              dplane_ctx_tc_class_get_handle(ctx));
  req->t.tcm_parent = TC_H_MAKE(TC_QDISC_MAJOR_ZEBRA, 0);
  req->t.tcm_info = 0;

  kind_str = dplane_ctx_tc_class_get_kind_str(ctx);

  if (op == DPLANE_OP_TC_CLASS_ADD || op == DPLANE_OP_TC_CLASS_UPDATE) {
    zlog_debug("netlink tclass encoder: op: %s kind: %s handle: %u",
         op == DPLANE_OP_TC_CLASS_UPDATE ? "update" : "add",
         kind_str, dplane_ctx_tc_class_get_handle(ctx));

    nl_attr_put(&req->n, datalen, TCA_KIND, kind_str,
          strlen(kind_str) + 1);

    nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS);

    switch (dplane_ctx_tc_class_get_kind(ctx)) {
    case TC_QDISC_HTB: {
      struct tc_htb_opt htb_opt = {};

      uint64_t rate = dplane_ctx_tc_class_get_rate(ctx),
         ceil = dplane_ctx_tc_class_get_ceil(ctx);

      uint64_t buffer, cbuffer;

      /* TODO: fetch mtu from interface */
      uint32_t mtu = 1500;

      uint32_t rtab[256];
      uint32_t ctab[256];

      ceil = MAX(rate, ceil);

      htb_opt.rate.rate = (rate >> 32 != 0) ? ~0U : rate;
      htb_opt.ceil.rate = (ceil >> 32 != 0) ? ~0U : ceil;

      buffer = rate / tc_get_freq() + mtu;
      cbuffer = ceil / tc_get_freq() + mtu;

      htb_opt.buffer = buffer;
      htb_opt.cbuffer = cbuffer;

      tc_calc_rate_table(&htb_opt.rate, rtab, mtu);
      tc_calc_rate_table(&htb_opt.ceil, ctab, mtu);

      htb_opt.ceil.mpu = htb_opt.rate.mpu = 0;
      htb_opt.ceil.overhead = htb_opt.rate.overhead = 0;

      if (rate >> 32 != 0) {
        nl_attr_put(&req->n, datalen, TCA_HTB_RATE64,
              &rate, sizeof(rate));
      }

      if (ceil >> 32 != 0) {
        nl_attr_put(&req->n, datalen, TCA_HTB_CEIL64,
              &ceil, sizeof(ceil));
      }

      nl_attr_put(&req->n, datalen, TCA_HTB_PARMS, &htb_opt,
            sizeof(htb_opt));

      nl_attr_put(&req->n, datalen, TCA_HTB_RTAB, rtab,
            sizeof(rtab));
      nl_attr_put(&req->n, datalen, TCA_HTB_CTAB, ctab,
            sizeof(ctab));
      break;
    }
    default:
      break;
    }

    nl_attr_nest_end(&req->n, nest);
  }

  return NLMSG_ALIGN(req->n.nlmsg_len);
}

static int netlink_tfilter_flower_port_type(uint8_t ip_proto, bool src)
{
  if (ip_proto == IPPROTO_TCP)
    return src ? TCA_FLOWER_KEY_TCP_SRC : TCA_FLOWER_KEY_TCP_DST;
  else if (ip_proto == IPPROTO_UDP)
    return src ? TCA_FLOWER_KEY_UDP_SRC : TCA_FLOWER_KEY_UDP_DST;
  else if (ip_proto == IPPROTO_SCTP)
    return src ? TCA_FLOWER_KEY_SCTP_SRC : TCA_FLOWER_KEY_SCTP_DST;
  else
    return -1;
}

static void netlink_tfilter_flower_put_options(struct nlmsghdr *n,
                 size_t datalen,
                 struct zebra_dplane_ctx *ctx)
{
  struct inet_prefix addr;
  uint32_t flags = 0, classid;
  uint8_t protocol = htons(dplane_ctx_tc_filter_get_eth_proto(ctx));
  uint32_t filter_bm = dplane_ctx_tc_filter_get_filter_bm(ctx);

  if (filter_bm & TC_FLOWER_SRC_IP) {
    const struct prefix *src_p =
      dplane_ctx_tc_filter_get_src_ip(ctx);

    if (tc_flower_get_inet_prefix(src_p, &addr) != 0)
      return;

    nl_attr_put(n, datalen,
          (addr.family == AF_INET) ? TCA_FLOWER_KEY_IPV4_SRC
                 : TCA_FLOWER_KEY_IPV6_SRC,
          addr.data, addr.bytelen);

    if (tc_flower_get_inet_mask(src_p, &addr) != 0)
      return;

    nl_attr_put(n, datalen,
          (addr.family == AF_INET)
            ? TCA_FLOWER_KEY_IPV4_SRC_MASK
            : TCA_FLOWER_KEY_IPV6_SRC_MASK,
          addr.data, addr.bytelen);
  }

  if (filter_bm & TC_FLOWER_DST_IP) {
    const struct prefix *dst_p =
      dplane_ctx_tc_filter_get_dst_ip(ctx);

    if (tc_flower_get_inet_prefix(dst_p, &addr) != 0)
      return;

    nl_attr_put(n, datalen,
          (addr.family == AF_INET) ? TCA_FLOWER_KEY_IPV4_DST
                 : TCA_FLOWER_KEY_IPV6_DST,
          addr.data, addr.bytelen);

    if (tc_flower_get_inet_mask(dst_p, &addr) != 0)
      return;

    nl_attr_put(n, datalen,
          (addr.family == AF_INET)
            ? TCA_FLOWER_KEY_IPV4_DST_MASK
            : TCA_FLOWER_KEY_IPV6_DST_MASK,
          addr.data, addr.bytelen);
  }

  if (filter_bm & TC_FLOWER_IP_PROTOCOL) {
    nl_attr_put8(n, datalen, TCA_FLOWER_KEY_IP_PROTO,
           dplane_ctx_tc_filter_get_ip_proto(ctx));
  }

  if (filter_bm & TC_FLOWER_SRC_PORT) {
    uint16_t min, max;

    min = dplane_ctx_tc_filter_get_src_port_min(ctx);
    max = dplane_ctx_tc_filter_get_src_port_max(ctx);

    if (max > min) {
      nl_attr_put16(n, datalen, TCA_FLOWER_KEY_PORT_SRC_MIN,
              htons(min));

      nl_attr_put16(n, datalen, TCA_FLOWER_KEY_PORT_SRC_MAX,
              htons(max));
    } else {
      int type = netlink_tfilter_flower_port_type(
        dplane_ctx_tc_filter_get_ip_proto(ctx), true);

      if (type < 0)
        return;

      nl_attr_put16(n, datalen, type, htons(min));
    }
  }

  if (filter_bm & TC_FLOWER_DST_PORT) {
    uint16_t min = dplane_ctx_tc_filter_get_dst_port_min(ctx),
       max = dplane_ctx_tc_filter_get_dst_port_max(ctx);

    if (max > min) {
      nl_attr_put16(n, datalen, TCA_FLOWER_KEY_PORT_DST_MIN,
              htons(min));

      nl_attr_put16(n, datalen, TCA_FLOWER_KEY_PORT_DST_MAX,
              htons(max));
    } else {
      int type = netlink_tfilter_flower_port_type(
        dplane_ctx_tc_filter_get_ip_proto(ctx), false);

      if (type < 0)
        return;

      nl_attr_put16(n, datalen, type, htons(min));
    }
  }

  if (filter_bm & TC_FLOWER_DSFIELD) {
    nl_attr_put8(n, datalen, TCA_FLOWER_KEY_IP_TOS,
           dplane_ctx_tc_filter_get_dsfield(ctx));
    nl_attr_put8(n, datalen, TCA_FLOWER_KEY_IP_TOS_MASK,
           dplane_ctx_tc_filter_get_dsfield_mask(ctx));
  }

  classid = TC_H_MAKE(TC_QDISC_MAJOR_ZEBRA,
          dplane_ctx_tc_filter_get_classid(ctx));
  nl_attr_put32(n, datalen, TCA_FLOWER_CLASSID, classid);

  nl_attr_put32(n, datalen, TCA_FLOWER_FLAGS, flags);

  nl_attr_put16(n, datalen, TCA_FLOWER_KEY_ETH_TYPE, protocol);
}

/*
 * Traffic control filter encoding
 */
static ssize_t netlink_tfilter_msg_encode(int cmd, struct zebra_dplane_ctx *ctx,
            void *data, size_t datalen)
{
  enum dplane_op_e op = dplane_ctx_get_op(ctx);

  struct nlsock *nl;
  const char *kind_str = NULL;

  struct rtattr *nest;

  uint16_t priority;
  uint16_t protocol;

  struct {
    struct nlmsghdr n;
    struct tcmsg t;
    char buf[0];
  } *req = (void *)data;

  if (datalen < sizeof(*req))
    return 0;

  nl = kernel_netlink_nlsock_lookup(dplane_ctx_get_ns_sock(ctx));

  memset(req, 0, sizeof(*req));

  req->n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  req->n.nlmsg_flags = NLM_F_CREATE | NLM_F_REQUEST;

  if (op == DPLANE_OP_TC_FILTER_UPDATE)
    req->n.nlmsg_flags |= NLM_F_REPLACE;

  req->n.nlmsg_type = cmd;

  req->n.nlmsg_pid = nl->snl.nl_pid;

  req->t.tcm_family = AF_UNSPEC;
  req->t.tcm_ifindex = dplane_ctx_get_ifindex(ctx);

  priority = dplane_ctx_tc_filter_get_priority(ctx);
  protocol = htons(dplane_ctx_tc_filter_get_eth_proto(ctx));

  req->t.tcm_info = TC_H_MAKE(priority << 16, protocol);
  req->t.tcm_handle = dplane_ctx_tc_filter_get_handle(ctx);
  req->t.tcm_parent = TC_H_MAKE(TC_QDISC_MAJOR_ZEBRA, 0);

  kind_str = dplane_ctx_tc_filter_get_kind_str(ctx);

  if (op == DPLANE_OP_TC_FILTER_ADD || op == DPLANE_OP_TC_FILTER_UPDATE) {
    nl_attr_put(&req->n, datalen, TCA_KIND, kind_str,
          strlen(kind_str) + 1);

    zlog_debug(
      "netlink tfilter encoder: op: %s priority: %u protocol: %u kind: %s handle: %u filter_bm: %u ip_proto: %u",
      op == DPLANE_OP_TC_FILTER_UPDATE ? "update" : "add",
      priority, protocol, kind_str,
      dplane_ctx_tc_filter_get_handle(ctx),
      dplane_ctx_tc_filter_get_filter_bm(ctx),
      dplane_ctx_tc_filter_get_ip_proto(ctx));

    nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS);
    switch (dplane_ctx_tc_filter_get_kind(ctx)) {
    case TC_FILTER_FLOWER: {
      netlink_tfilter_flower_put_options(&req->n, datalen,
                 ctx);
      break;
    }
    default:
      break;
    }
    nl_attr_nest_end(&req->n, nest);
  }

  return NLMSG_ALIGN(req->n.nlmsg_len);
}

static ssize_t netlink_newqdisc_msg_encoder(struct zebra_dplane_ctx *ctx,
              void *buf, size_t buflen)
{
  return netlink_qdisc_msg_encode(RTM_NEWQDISC, ctx, buf, buflen);
}

static ssize_t netlink_delqdisc_msg_encoder(struct zebra_dplane_ctx *ctx,
              void *buf, size_t buflen)
{
  return netlink_qdisc_msg_encode(RTM_DELQDISC, ctx, buf, buflen);
}

static ssize_t netlink_newtclass_msg_encoder(struct zebra_dplane_ctx *ctx,
               void *buf, size_t buflen)
{
  return netlink_tclass_msg_encode(RTM_NEWTCLASS, ctx, buf, buflen);
}

static ssize_t netlink_deltclass_msg_encoder(struct zebra_dplane_ctx *ctx,
               void *buf, size_t buflen)
{
  return netlink_tclass_msg_encode(RTM_DELTCLASS, ctx, buf, buflen);
}

static ssize_t netlink_newtfilter_msg_encoder(struct zebra_dplane_ctx *ctx,
                void *buf, size_t buflen)
{
  return netlink_tfilter_msg_encode(RTM_NEWTFILTER, ctx, buf, buflen);
}

static ssize_t netlink_deltfilter_msg_encoder(struct zebra_dplane_ctx *ctx,
                void *buf, size_t buflen)
{
  return netlink_tfilter_msg_encode(RTM_DELTFILTER, ctx, buf, buflen);
}

enum netlink_msg_status
netlink_put_tc_qdisc_update_msg(struct nl_batch *bth,
        struct zebra_dplane_ctx *ctx)
{
  enum dplane_op_e op;
  enum netlink_msg_status ret;

  op = dplane_ctx_get_op(ctx);

  if (op == DPLANE_OP_TC_QDISC_INSTALL) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_newqdisc_msg_encoder, false);
  } else if (op == DPLANE_OP_TC_QDISC_UNINSTALL) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_delqdisc_msg_encoder, false);
  } else {
    return FRR_NETLINK_ERROR;
  }

  return ret;
}

enum netlink_msg_status
netlink_put_tc_class_update_msg(struct nl_batch *bth,
        struct zebra_dplane_ctx *ctx)
{
  enum dplane_op_e op;
  enum netlink_msg_status ret;

  op = dplane_ctx_get_op(ctx);

  if (op == DPLANE_OP_TC_CLASS_ADD || op == DPLANE_OP_TC_CLASS_UPDATE) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_newtclass_msg_encoder, false);
  } else if (op == DPLANE_OP_TC_CLASS_DELETE) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_deltclass_msg_encoder, false);
  } else {
    return FRR_NETLINK_ERROR;
  }

  return ret;
}

enum netlink_msg_status
netlink_put_tc_filter_update_msg(struct nl_batch *bth,
         struct zebra_dplane_ctx *ctx)
{
  enum dplane_op_e op;
  enum netlink_msg_status ret;

  op = dplane_ctx_get_op(ctx);

  if (op == DPLANE_OP_TC_FILTER_ADD) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_newtfilter_msg_encoder, false);
  } else if (op == DPLANE_OP_TC_FILTER_UPDATE) {
    /*
     * Replace will fail if either filter type or the number of
     * filter options is changed, so DEL then NEW
     *
     * TFILTER may have refs to TCLASS.
     */

    (void)netlink_batch_add_msg(
      bth, ctx, netlink_deltfilter_msg_encoder, false);
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_newtfilter_msg_encoder, false);
  } else if (op == DPLANE_OP_TC_FILTER_DELETE) {
    ret = netlink_batch_add_msg(
      bth, ctx, netlink_deltfilter_msg_encoder, false);
  } else {
    return FRR_NETLINK_ERROR;
  }

  return ret;
}

/*
 * Request filters from the kernel
 */
static int netlink_request_filters(struct zebra_ns *zns, int family, int type,
           ifindex_t ifindex)
{
  struct {
    struct nlmsghdr n;
    struct tcmsg tc;
  } req;

  memset(&req, 0, sizeof(req));
  req.n.nlmsg_type = type;
  req.n.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST;
  req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  req.tc.tcm_family = family;
  req.tc.tcm_ifindex = ifindex;

  return netlink_request(&zns->netlink_cmd, &req);
}

/*
 * Request queue discipline from the kernel
 */
static int netlink_request_qdiscs(struct zebra_ns *zns, int family, int type)
{
  struct {
    struct nlmsghdr n;
    struct tcmsg tc;
  } req;

  memset(&req, 0, sizeof(req));
  req.n.nlmsg_type = type;
  req.n.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST;
  req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  req.tc.tcm_family = family;

  return netlink_request(&zns->netlink_cmd, &req);
}

int netlink_qdisc_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
{
  struct tcmsg *tcm;
  struct zebra_tc_qdisc qdisc = {};
  enum tc_qdisc_kind kind = TC_QDISC_UNSPEC;
  const char *kind_str = "Unknown";

  int len;
  struct rtattr *tb[TCA_MAX + 1];

  frrtrace(3, frr_zebra, netlink_tc_qdisc_change, h, ns_id, startup);

  len = h->nlmsg_len - NLMSG_LENGTH(sizeof(struct tcmsg));

  if (len < 0) {
    zlog_err(
      "%s: Message received from netlink is of a broken size %d %zu",
      __func__, h->nlmsg_len,
      (size_t)NLMSG_LENGTH(sizeof(struct tcmsg)));
    return -1;
  }

  tcm = NLMSG_DATA(h);
  netlink_parse_rtattr(tb, TCA_MAX, TCA_RTA(tcm), len);

  if (RTA_DATA(tb[TCA_KIND])) {
    kind_str = (const char *)RTA_DATA(tb[TCA_KIND]);

    kind = tc_qdisc_str2kind(kind_str);
  }

  qdisc.qdisc.ifindex = tcm->tcm_ifindex;

  switch (kind) {
  case TC_QDISC_NOQUEUE:
    /* "noqueue" is the default qdisc */
    break;
  case TC_QDISC_HTB:
  case TC_QDISC_UNSPEC:
    break;
  }

  if (tb[TCA_OPTIONS] != NULL) {
    struct rtattr *options[TCA_HTB_MAX + 1];

    netlink_parse_rtattr_nested(options, TCA_HTB_MAX,
              tb[TCA_OPTIONS]);

    /* TODO: more details */
    /* struct tc_htb_glob *glob = RTA_DATA(options[TCA_HTB_INIT]);
     */
  }

  if (h->nlmsg_type == RTM_NEWQDISC) {
    if (startup &&
        TC_H_MAJ(tcm->tcm_handle) == TC_QDISC_MAJOR_ZEBRA) {
      enum zebra_dplane_result ret;

      ret = dplane_tc_qdisc_uninstall(&qdisc);

      zlog_debug("%s: %s leftover qdisc: ifindex %d kind %s",
           __func__,
           ((ret == ZEBRA_DPLANE_REQUEST_FAILURE)
              ? "Failed to remove"
              : "Removed"),
           qdisc.qdisc.ifindex, kind_str);
    }
  }

  return 0;
}

int netlink_tclass_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
{
  struct tcmsg *tcm;

  int len;
  struct rtattr *tb[TCA_MAX + 1];

  frrtrace(3, frr_zebra, netlink_tc_class_change, h, ns_id, startup);

  len = h->nlmsg_len - NLMSG_LENGTH(sizeof(struct tcmsg));

  if (len < 0) {
    zlog_err(
      "%s: Message received from netlink is of a broken size %d %zu",
      __func__, h->nlmsg_len,
      (size_t)NLMSG_LENGTH(sizeof(struct tcmsg)));
    return -1;
  }

  tcm = NLMSG_DATA(h);
  netlink_parse_rtattr(tb, TCA_MAX, TCA_RTA(tcm), len);


  if (tb[TCA_OPTIONS] != NULL) {
    struct rtattr *options[TCA_HTB_MAX + 1];

    netlink_parse_rtattr_nested(options, TCA_HTB_MAX,
              tb[TCA_OPTIONS]);

    /* TODO: more details */
    /* struct tc_htb_opt *opt = RTA_DATA(options[TCA_HTB_PARMS]); */
  }

  return 0;
}

int netlink_tfilter_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
{
  struct tcmsg *tcm;

  int len;
  struct rtattr *tb[TCA_MAX + 1];

  frrtrace(3, frr_zebra, netlink_tc_filter_change, h, ns_id, startup);

  len = h->nlmsg_len - NLMSG_LENGTH(sizeof(struct tcmsg));

  if (len < 0) {
    zlog_err(
      "%s: Message received from netlink is of a broken size %d %zu",
      __func__, h->nlmsg_len,
      (size_t)NLMSG_LENGTH(sizeof(struct tcmsg)));
    return -1;
  }

  tcm = NLMSG_DATA(h);
  netlink_parse_rtattr(tb, TCA_MAX, TCA_RTA(tcm), len);

  return 0;
}

int netlink_qdisc_read(struct zebra_ns *zns)
{
  int ret;
  struct zebra_dplane_info dp_info;

  zebra_dplane_info_from_zns(&dp_info, zns, true);

  ret = netlink_request_qdiscs(zns, AF_UNSPEC, RTM_GETQDISC);
  if (ret < 0)
    return ret;

  ret = netlink_parse_info(netlink_qdisc_change, &zns->netlink_cmd,
         &dp_info, 0, true);
  if (ret < 0)
    return ret;

  return 0;
}

int netlink_tfilter_read_for_interface(struct zebra_ns *zns, ifindex_t ifindex)
{
  int ret;
  struct zebra_dplane_info dp_info;

  zebra_dplane_info_from_zns(&dp_info, zns, true);

  ret = netlink_request_filters(zns, AF_UNSPEC, RTM_GETTFILTER, ifindex);
  if (ret < 0)
    return ret;

  ret = netlink_parse_info(netlink_tfilter_change, &zns->netlink_cmd,
         &dp_info, 0, true);
  if (ret < 0)
    return ret;

  return 0;
}

#endif /* HAVE_NETLINK */

Coverage Report

Created: 2025-12-12 06:43