From 58cff782cc55eb755826c649976aea9f5f8b3086 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Tue, 26 May 2020 14:29:00 +0200 Subject: [PATCH] flow_dissector: Parse multiple MPLS Label Stack Entries The current MPLS dissector only parses the first MPLS Label Stack Entry (second LSE can be parsed too, but only to set a key_id). This patch adds the possibility to parse several LSEs by making __skb_flow_dissect_mpls() return FLOW_DISSECT_RET_PROTO_AGAIN as long as the Bottom Of Stack bit hasn't been seen, up to a maximum of FLOW_DIS_MPLS_MAX entries. FLOW_DIS_MPLS_MAX is arbitrarily set to 7. This should be enough for many practical purposes, without wasting too much space. To record the parsed values, flow_dissector_key_mpls is modified to store an array of stack entries, instead of just the values of the first one. A bit field, "used_lses", is also added to keep track of the LSEs that have been set. The objective is to avoid defining a new FLOW_DISSECTOR_KEY_MPLS_XX for each level of the MPLS stack. TC flower is adapted for the new struct flow_dissector_key_mpls layout. Matching on several MPLS Label Stack Entries will be added in the next patch. The NFP and MLX5 drivers are also adapted: nfp_flower_compile_mac() and mlx5's parse_tunnel() now verify that the rule only uses the first LSE and fail if it doesn't. Finally, the behaviour of the FLOW_DISSECTOR_KEY_MPLS_ENTROPY key is slightly modified. Instead of recording the first Entropy Label, it now records the last one. This shouldn't have any consequences since there doesn't seem to have any user of FLOW_DISSECTOR_KEY_MPLS_ENTROPY in the tree. We'd probably better do a hash of all parsed MPLS labels instead (excluding reserved labels) anyway. That'd give better entropy and would probably also simplify the code. But that's not the purpose of this patch, so I'm keeping that as a future possible improvement. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller --- .../mellanox/mlx5/core/en/tc_tun_mplsoudp.c | 31 +++++++---- .../net/ethernet/netronome/nfp/flower/match.c | 42 +++++++++++---- include/net/flow_dissector.h | 14 ++++- net/core/flow_dissector.c | 49 +++++++++++------ net/sched/cls_flower.c | 52 +++++++++++++------ 5 files changed, 134 insertions(+), 54 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_mplsoudp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_mplsoudp.c index 98ee62e427d2..b4a3c96d34fd 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_mplsoudp.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_mplsoudp.c @@ -101,25 +101,36 @@ static int parse_tunnel(struct mlx5e_priv *priv, flow_rule_match_mpls(rule, &match); - MLX5_SET(fte_match_set_misc2, misc2_c, - outer_first_mpls_over_udp.mpls_label, match.mask->mpls_label); - MLX5_SET(fte_match_set_misc2, misc2_v, - outer_first_mpls_over_udp.mpls_label, match.key->mpls_label); + /* Only support matching the first LSE */ + if (match.mask->used_lses != 1) + return -EOPNOTSUPP; MLX5_SET(fte_match_set_misc2, misc2_c, - outer_first_mpls_over_udp.mpls_exp, match.mask->mpls_tc); + outer_first_mpls_over_udp.mpls_label, + match.mask->ls[0].mpls_label); MLX5_SET(fte_match_set_misc2, misc2_v, - outer_first_mpls_over_udp.mpls_exp, match.key->mpls_tc); + outer_first_mpls_over_udp.mpls_label, + match.key->ls[0].mpls_label); MLX5_SET(fte_match_set_misc2, misc2_c, - outer_first_mpls_over_udp.mpls_s_bos, match.mask->mpls_bos); + outer_first_mpls_over_udp.mpls_exp, + match.mask->ls[0].mpls_tc); MLX5_SET(fte_match_set_misc2, misc2_v, - outer_first_mpls_over_udp.mpls_s_bos, match.key->mpls_bos); + outer_first_mpls_over_udp.mpls_exp, match.key->ls[0].mpls_tc); MLX5_SET(fte_match_set_misc2, misc2_c, - outer_first_mpls_over_udp.mpls_ttl, match.mask->mpls_ttl); + outer_first_mpls_over_udp.mpls_s_bos, + match.mask->ls[0].mpls_bos); MLX5_SET(fte_match_set_misc2, misc2_v, - outer_first_mpls_over_udp.mpls_ttl, match.key->mpls_ttl); + outer_first_mpls_over_udp.mpls_s_bos, + match.key->ls[0].mpls_bos); + + MLX5_SET(fte_match_set_misc2, misc2_c, + outer_first_mpls_over_udp.mpls_ttl, + match.mask->ls[0].mpls_ttl); + MLX5_SET(fte_match_set_misc2, misc2_v, + outer_first_mpls_over_udp.mpls_ttl, + match.key->ls[0].mpls_ttl); spec->match_criteria_enable |= MLX5_MATCH_MISC_PARAMETERS_2; return 0; diff --git a/drivers/net/ethernet/netronome/nfp/flower/match.c b/drivers/net/ethernet/netronome/nfp/flower/match.c index 546bc01d507d..f7f01e2e3dce 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/match.c +++ b/drivers/net/ethernet/netronome/nfp/flower/match.c @@ -74,9 +74,10 @@ nfp_flower_compile_port(struct nfp_flower_in_port *frame, u32 cmsg_port, return 0; } -static void +static int nfp_flower_compile_mac(struct nfp_flower_mac_mpls *ext, - struct nfp_flower_mac_mpls *msk, struct flow_rule *rule) + struct nfp_flower_mac_mpls *msk, struct flow_rule *rule, + struct netlink_ext_ack *extack) { memset(ext, 0, sizeof(struct nfp_flower_mac_mpls)); memset(msk, 0, sizeof(struct nfp_flower_mac_mpls)); @@ -97,14 +98,28 @@ nfp_flower_compile_mac(struct nfp_flower_mac_mpls *ext, u32 t_mpls; flow_rule_match_mpls(rule, &match); - t_mpls = FIELD_PREP(NFP_FLOWER_MASK_MPLS_LB, match.key->mpls_label) | - FIELD_PREP(NFP_FLOWER_MASK_MPLS_TC, match.key->mpls_tc) | - FIELD_PREP(NFP_FLOWER_MASK_MPLS_BOS, match.key->mpls_bos) | + + /* Only support matching the first LSE */ + if (match.mask->used_lses != 1) { + NL_SET_ERR_MSG_MOD(extack, + "unsupported offload: invalid LSE depth for MPLS match offload"); + return -EOPNOTSUPP; + } + + t_mpls = FIELD_PREP(NFP_FLOWER_MASK_MPLS_LB, + match.key->ls[0].mpls_label) | + FIELD_PREP(NFP_FLOWER_MASK_MPLS_TC, + match.key->ls[0].mpls_tc) | + FIELD_PREP(NFP_FLOWER_MASK_MPLS_BOS, + match.key->ls[0].mpls_bos) | NFP_FLOWER_MASK_MPLS_Q; ext->mpls_lse = cpu_to_be32(t_mpls); - t_mpls = FIELD_PREP(NFP_FLOWER_MASK_MPLS_LB, match.mask->mpls_label) | - FIELD_PREP(NFP_FLOWER_MASK_MPLS_TC, match.mask->mpls_tc) | - FIELD_PREP(NFP_FLOWER_MASK_MPLS_BOS, match.mask->mpls_bos) | + t_mpls = FIELD_PREP(NFP_FLOWER_MASK_MPLS_LB, + match.mask->ls[0].mpls_label) | + FIELD_PREP(NFP_FLOWER_MASK_MPLS_TC, + match.mask->ls[0].mpls_tc) | + FIELD_PREP(NFP_FLOWER_MASK_MPLS_BOS, + match.mask->ls[0].mpls_bos) | NFP_FLOWER_MASK_MPLS_Q; msk->mpls_lse = cpu_to_be32(t_mpls); } else if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) { @@ -121,6 +136,8 @@ nfp_flower_compile_mac(struct nfp_flower_mac_mpls *ext, msk->mpls_lse = cpu_to_be32(NFP_FLOWER_MASK_MPLS_Q); } } + + return 0; } static void @@ -461,9 +478,12 @@ int nfp_flower_compile_flow_match(struct nfp_app *app, msk += sizeof(struct nfp_flower_in_port); if (NFP_FLOWER_LAYER_MAC & key_ls->key_layer) { - nfp_flower_compile_mac((struct nfp_flower_mac_mpls *)ext, - (struct nfp_flower_mac_mpls *)msk, - rule); + err = nfp_flower_compile_mac((struct nfp_flower_mac_mpls *)ext, + (struct nfp_flower_mac_mpls *)msk, + rule, extack); + if (err) + return err; + ext += sizeof(struct nfp_flower_mac_mpls); msk += sizeof(struct nfp_flower_mac_mpls); } diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index 628383915827..4fb1a69c6ecf 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -59,13 +59,25 @@ struct flow_dissector_key_vlan { __be16 vlan_tpid; }; -struct flow_dissector_key_mpls { +struct flow_dissector_mpls_lse { u32 mpls_ttl:8, mpls_bos:1, mpls_tc:3, mpls_label:20; }; +#define FLOW_DIS_MPLS_MAX 7 +struct flow_dissector_key_mpls { + struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */ + u8 used_lses; /* One bit set for each Label Stack Entry in use */ +}; + +static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls, + int lse_index) +{ + mpls->used_lses |= 1 << lse_index; +} + #define FLOW_DIS_TUN_OPTS_MAX 255 /** * struct flow_dissector_key_enc_opts: diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 5dceed467f64..0aeb33572feb 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -480,47 +480,59 @@ EXPORT_SYMBOL(skb_flow_dissect_tunnel_info); static enum flow_dissect_ret __skb_flow_dissect_mpls(const struct sk_buff *skb, struct flow_dissector *flow_dissector, - void *target_container, void *data, int nhoff, int hlen) + void *target_container, void *data, int nhoff, int hlen, + int lse_index, bool *entropy_label) { - struct flow_dissector_key_keyid *key_keyid; - struct mpls_label *hdr, _hdr[2]; - u32 entry, label; + struct mpls_label *hdr, _hdr; + u32 entry, label, bos; if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS_ENTROPY) && !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) return FLOW_DISSECT_RET_OUT_GOOD; + if (lse_index >= FLOW_DIS_MPLS_MAX) + return FLOW_DISSECT_RET_OUT_GOOD; + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); if (!hdr) return FLOW_DISSECT_RET_OUT_BAD; - entry = ntohl(hdr[0].entry); + entry = ntohl(hdr->entry); label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT; + bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT; if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) { struct flow_dissector_key_mpls *key_mpls; + struct flow_dissector_mpls_lse *lse; key_mpls = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_MPLS, target_container); - key_mpls->mpls_label = label; - key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK) - >> MPLS_LS_TTL_SHIFT; - key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK) - >> MPLS_LS_TC_SHIFT; - key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK) - >> MPLS_LS_S_SHIFT; + lse = &key_mpls->ls[lse_index]; + + lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT; + lse->mpls_bos = bos; + lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT; + lse->mpls_label = label; + dissector_set_mpls_lse(key_mpls, lse_index); } - if (label == MPLS_LABEL_ENTROPY) { + if (*entropy_label && + dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) { + struct flow_dissector_key_keyid *key_keyid; + key_keyid = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_MPLS_ENTROPY, target_container); - key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK); + key_keyid->keyid = cpu_to_be32(label); } - return FLOW_DISSECT_RET_OUT_GOOD; + + *entropy_label = label == MPLS_LABEL_ENTROPY; + + return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN; } static enum flow_dissect_ret @@ -979,6 +991,8 @@ bool __skb_flow_dissect(const struct net *net, struct bpf_prog *attached = NULL; enum flow_dissect_ret fdret; enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX; + bool mpls_el = false; + int mpls_lse = 0; int num_hdrs = 0; u8 ip_proto = 0; bool ret; @@ -1278,7 +1292,10 @@ proto_again: case htons(ETH_P_MPLS_MC): fdret = __skb_flow_dissect_mpls(skb, flow_dissector, target_container, data, - nhoff, hlen); + nhoff, hlen, mpls_lse, + &mpls_el); + nhoff += sizeof(struct mpls_label); + mpls_lse++; break; case htons(ETH_P_FCOE): if ((hlen - nhoff) < FCOE_HEADER_LEN) { diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 0c574700da75..f524afe0b7f5 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -781,9 +781,17 @@ static int fl_set_key_mpls(struct nlattr **tb, struct flow_dissector_key_mpls *key_mask, struct netlink_ext_ack *extack) { + struct flow_dissector_mpls_lse *lse_mask; + struct flow_dissector_mpls_lse *lse_val; + + lse_val = &key_val->ls[0]; + lse_mask = &key_mask->ls[0]; + if (tb[TCA_FLOWER_KEY_MPLS_TTL]) { - key_val->mpls_ttl = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TTL]); - key_mask->mpls_ttl = MPLS_TTL_MASK; + lse_val->mpls_ttl = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TTL]); + lse_mask->mpls_ttl = MPLS_TTL_MASK; + dissector_set_mpls_lse(key_val, 0); + dissector_set_mpls_lse(key_mask, 0); } if (tb[TCA_FLOWER_KEY_MPLS_BOS]) { u8 bos = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_BOS]); @@ -794,8 +802,10 @@ static int fl_set_key_mpls(struct nlattr **tb, "Bottom Of Stack (BOS) must be 0 or 1"); return -EINVAL; } - key_val->mpls_bos = bos; - key_mask->mpls_bos = MPLS_BOS_MASK; + lse_val->mpls_bos = bos; + lse_mask->mpls_bos = MPLS_BOS_MASK; + dissector_set_mpls_lse(key_val, 0); + dissector_set_mpls_lse(key_mask, 0); } if (tb[TCA_FLOWER_KEY_MPLS_TC]) { u8 tc = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TC]); @@ -806,8 +816,10 @@ static int fl_set_key_mpls(struct nlattr **tb, "Traffic Class (TC) must be between 0 and 7"); return -EINVAL; } - key_val->mpls_tc = tc; - key_mask->mpls_tc = MPLS_TC_MASK; + lse_val->mpls_tc = tc; + lse_mask->mpls_tc = MPLS_TC_MASK; + dissector_set_mpls_lse(key_val, 0); + dissector_set_mpls_lse(key_mask, 0); } if (tb[TCA_FLOWER_KEY_MPLS_LABEL]) { u32 label = nla_get_u32(tb[TCA_FLOWER_KEY_MPLS_LABEL]); @@ -818,8 +830,10 @@ static int fl_set_key_mpls(struct nlattr **tb, "Label must be between 0 and 1048575"); return -EINVAL; } - key_val->mpls_label = label; - key_mask->mpls_label = MPLS_LABEL_MASK; + lse_val->mpls_label = label; + lse_mask->mpls_label = MPLS_LABEL_MASK; + dissector_set_mpls_lse(key_val, 0); + dissector_set_mpls_lse(key_mask, 0); } return 0; } @@ -2222,31 +2236,37 @@ static int fl_dump_key_mpls(struct sk_buff *skb, struct flow_dissector_key_mpls *mpls_key, struct flow_dissector_key_mpls *mpls_mask) { + struct flow_dissector_mpls_lse *lse_mask; + struct flow_dissector_mpls_lse *lse_key; int err; if (!memchr_inv(mpls_mask, 0, sizeof(*mpls_mask))) return 0; - if (mpls_mask->mpls_ttl) { + + lse_mask = &mpls_mask->ls[0]; + lse_key = &mpls_key->ls[0]; + + if (lse_mask->mpls_ttl) { err = nla_put_u8(skb, TCA_FLOWER_KEY_MPLS_TTL, - mpls_key->mpls_ttl); + lse_key->mpls_ttl); if (err) return err; } - if (mpls_mask->mpls_tc) { + if (lse_mask->mpls_tc) { err = nla_put_u8(skb, TCA_FLOWER_KEY_MPLS_TC, - mpls_key->mpls_tc); + lse_key->mpls_tc); if (err) return err; } - if (mpls_mask->mpls_label) { + if (lse_mask->mpls_label) { err = nla_put_u32(skb, TCA_FLOWER_KEY_MPLS_LABEL, - mpls_key->mpls_label); + lse_key->mpls_label); if (err) return err; } - if (mpls_mask->mpls_bos) { + if (lse_mask->mpls_bos) { err = nla_put_u8(skb, TCA_FLOWER_KEY_MPLS_BOS, - mpls_key->mpls_bos); + lse_key->mpls_bos); if (err) return err; }