diff options
Diffstat (limited to 'zebra/tc_netlink.c')
-rw-r--r-- | zebra/tc_netlink.c | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/zebra/tc_netlink.c b/zebra/tc_netlink.c new file mode 100644 index 0000000..afa03a4 --- /dev/null +++ b/zebra/tc_netlink.c @@ -0,0 +1,468 @@ +/* + * Zebra Traffic Control (TC) interaction with the kernel using netlink. + * + * Copyright (C) 2022 Shichu Yang + * + * This file is part of FRR. + * + * FRR 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, or (at your option) any + * later version. + * + * FRR is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with FRR; see the file COPYING. If not, write to the Free + * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + */ + +#include <zebra.h> + +#ifdef HAVE_NETLINK + +#include <netinet/if_ether.h> +#include <sys/socket.h> + +#include "if.h" +#include "prefix.h" +#include "vrf.h" + +#include <linux/fib_rules.h> +#include <linux/pkt_cls.h> +#include <linux/pkt_sched.h> +#include "zebra/zserv.h" +#include "zebra/zebra_ns.h" +#include "zebra/zebra_vrf.h" +#include "zebra/rt.h" +#include "zebra/interface.h" +#include "zebra/debug.h" +#include "zebra/rtadv.h" +#include "zebra/kernel_netlink.h" +#include "zebra/tc_netlink.h" +#include "zebra/zebra_errors.h" +#include "zebra/zebra_dplane.h" +#include "zebra/zebra_trace.h" + +/* TODO: move these bitflags to zebra_tc.h */ +#define TC_FILTER_SRC_IP (1 << 0) +#define TC_FILTER_DST_IP (1 << 1) +#define TC_FILTER_IP_PROTOCOL (1 << 9) + +#define TC_FREQ_DEFAULT (100) + +#define TC_MAJOR_BASE (0x1000u) +#define TC_MINOR_NOCLASS (0xffffu) + +#define TC_FILTER_MASK (0x8000u) + +#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 inline uint32_t tc_make_handle(uint16_t major, uint16_t minor) +{ + return (major) << 16 | (minor); +} + +static inline uint32_t tc_get_handle(struct zebra_dplane_ctx *ctx, + uint16_t minor) +{ + uint16_t major = TC_MAJOR_BASE + (uint16_t)dplane_ctx_get_ifindex(ctx); + + return tc_make_handle(major, minor); +} + +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 = "htb"; + + struct tc_htb_glob htb_glob = { + .rate2quantum = 10, .version = 3, .defcls = TC_MINOR_NOCLASS}; + + 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_handle = tc_get_handle(ctx, 0); + req->t.tcm_parent = TC_H_ROOT; + + nl_attr_put(&req->n, datalen, TCA_KIND, kind, strlen(kind) + 1); + + nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS); + + nl_attr_put(&req->n, datalen, TCA_HTB_INIT, &htb_glob, + sizeof(htb_glob)); + nl_attr_nest_end(&req->n, nest); + + 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) +{ + struct nlsock *nl; + struct tc_htb_opt htb_opt = {}; + + uint64_t rate, ceil; + uint64_t buffer, cbuffer; + + /* TODO: fetch mtu from interface */ + uint32_t mtu = 0; + + uint32_t rtab[256]; + uint32_t ctab[256]; + + 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_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_get_handle(ctx, 1); + req->t.tcm_parent = tc_get_handle(ctx, 0); + + rate = dplane_ctx_tc_get_rate(ctx); + ceil = dplane_ctx_tc_get_ceil(ctx); + + ceil = ceil < rate ? 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(), cbuffer = ceil / tc_get_freq(); + + 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; + + nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS); + + if (rate >> 32 != 0) { + nl_attr_put(&req->n, datalen, TCA_HTB_CEIL64, &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)); + nl_attr_nest_end(&req->n, nest); + + return NLMSG_ALIGN(req->n.nlmsg_len); +} + +/* + * Traffic control filter encoding (only "flower" supported) + */ +static ssize_t netlink_tfilter_msg_encode(int cmd, struct zebra_dplane_ctx *ctx, + void *data, size_t datalen) +{ + struct nlsock *nl; + struct rtattr *nest; + + const char *kind = "flower"; + + uint16_t priority; + uint16_t protocol; + uint32_t classid; + uint32_t filter_bm; + uint32_t flags = 0; + + struct inet_prefix addr; + + 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_EXCL; + + 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); + + /* TODO: priority and layer-3 protocol support */ + priority = 0; + protocol = htons(ETH_P_IP); + classid = tc_get_handle(ctx, 1); + filter_bm = dplane_ctx_tc_get_filter_bm(ctx); + + req->t.tcm_info = tc_make_handle(priority, protocol); + + req->t.tcm_handle = 1; + req->t.tcm_parent = tc_get_handle(ctx, 0); + + nl_attr_put(&req->n, datalen, TCA_KIND, kind, strlen(kind) + 1); + nest = nl_attr_nest(&req->n, datalen, TCA_OPTIONS); + + nl_attr_put(&req->n, datalen, TCA_FLOWER_CLASSID, &classid, + sizeof(classid)); + + if (filter_bm & TC_FILTER_SRC_IP) { + const struct prefix *src_p = dplane_ctx_tc_get_src_ip(ctx); + + if (tc_flower_get_inet_prefix(src_p, &addr) != 0) + return 0; + + nl_attr_put(&req->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 0; + + nl_attr_put(&req->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_FILTER_DST_IP) { + const struct prefix *dst_p = dplane_ctx_tc_get_dst_ip(ctx); + + if (tc_flower_get_inet_prefix(dst_p, &addr) != 0) + return 0; + + nl_attr_put(&req->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 0; + + nl_attr_put(&req->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_FILTER_IP_PROTOCOL) { + nl_attr_put8(&req->n, datalen, TCA_FLOWER_KEY_IP_PROTO, + dplane_ctx_tc_get_ip_proto(ctx)); + } + + nl_attr_put32(&req->n, datalen, TCA_FLOWER_FLAGS, flags); + + nl_attr_put16(&req->n, datalen, TCA_FLOWER_KEY_ETH_TYPE, protocol); + 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_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_newtfilter_msg_encoder(struct zebra_dplane_ctx *ctx, + void *buf, size_t buflen) +{ + return netlink_tfilter_msg_encode(RTM_NEWTFILTER, ctx, buf, buflen); +} + +enum netlink_msg_status netlink_put_tc_update_msg(struct nl_batch *bth, + struct zebra_dplane_ctx *ctx) +{ + /* TODO: error handling and other actions (delete, replace, ...) */ + + netlink_batch_add_msg(bth, ctx, netlink_newqdisc_msg_encoder, false); + netlink_batch_add_msg(bth, ctx, netlink_newtclass_msg_encoder, false); + return netlink_batch_add_msg(bth, ctx, netlink_newtfilter_msg_encoder, + false); +} + +#endif /* HAVE_NETLINK */ |