From patchwork Sat Jun 11 10:47:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Mayer X-Patchwork-Id: 12878438 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 523A2C433EF for ; Sat, 11 Jun 2022 10:48:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232333AbiFKKsi (ORCPT ); Sat, 11 Jun 2022 06:48:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58166 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229609AbiFKKsg (ORCPT ); Sat, 11 Jun 2022 06:48:36 -0400 Received: from smtp.uniroma2.it (smtp.uniroma2.it [160.80.6.16]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E8069FF0; Sat, 11 Jun 2022 03:48:33 -0700 (PDT) Received: from localhost.localdomain ([160.80.103.126]) by smtp-2015.uniroma2.it (8.14.4/8.14.4/Debian-8) with ESMTP id 25BAm7gL007213 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Sat, 11 Jun 2022 12:48:09 +0200 From: Andrea Mayer To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Stefano Salsano , Paolo Lungaroni , Ahmed Abdelsalam , Andrea Mayer Subject: [net-next v1 1/2] seg6: add netlink_ext_ack support in parsing SRv6 behavior attributes Date: Sat, 11 Jun 2022 12:47:49 +0200 Message-Id: <20220611104750.2724-2-andrea.mayer@uniroma2.it> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220611104750.2724-1-andrea.mayer@uniroma2.it> References: <20220611104750.2724-1-andrea.mayer@uniroma2.it> MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 0.100.0 at smtp-2015 X-Virus-Status: Clean Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org An SRv6 behavior instance can be set up using mandatory and/or optional attributes. In the setup phase, each supplied attribute is parsed and processed. If the parsing operation fails, the creation of the behavior instance stops and an error number/code is reported to the user. In many cases, it is challenging for the user to figure out exactly what happened by relying only on the error code. For this reason, we add the support for netlink_ext_ack in parsing SRv6 behavior attributes. In this way, when an SRv6 behavior attribute is parsed and an error occurs, the kernel can send a message to the userspace describing the error through a meaningful text message in addition to the classic error code. Signed-off-by: Andrea Mayer --- net/ipv6/seg6_local.c | 44 +++++++++++++++++++++++++++---------------- 1 file changed, 28 insertions(+), 16 deletions(-) diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 9fbe243a0e81..5ea51ee2ef71 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -1135,7 +1135,8 @@ static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = { [SEG6_LOCAL_COUNTERS] = { .type = NLA_NESTED }, }; -static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct ipv6_sr_hdr *srh; int len; @@ -1192,7 +1193,8 @@ static void destroy_attr_srh(struct seg6_local_lwt *slwt) kfree(slwt->srh); } -static int parse_nla_table(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_table(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { slwt->table = nla_get_u32(attrs[SEG6_LOCAL_TABLE]); @@ -1226,7 +1228,8 @@ seg6_end_dt_info *seg6_possible_end_dt_info(struct seg6_local_lwt *slwt) } static int parse_nla_vrftable(struct nlattr **attrs, - struct seg6_local_lwt *slwt) + struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct seg6_end_dt_info *info = seg6_possible_end_dt_info(slwt); @@ -1262,7 +1265,8 @@ static int cmp_nla_vrftable(struct seg6_local_lwt *a, struct seg6_local_lwt *b) return 0; } -static int parse_nla_nh4(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_nh4(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { memcpy(&slwt->nh4, nla_data(attrs[SEG6_LOCAL_NH4]), sizeof(struct in_addr)); @@ -1288,7 +1292,8 @@ static int cmp_nla_nh4(struct seg6_local_lwt *a, struct seg6_local_lwt *b) return memcmp(&a->nh4, &b->nh4, sizeof(struct in_addr)); } -static int parse_nla_nh6(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_nh6(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { memcpy(&slwt->nh6, nla_data(attrs[SEG6_LOCAL_NH6]), sizeof(struct in6_addr)); @@ -1314,7 +1319,8 @@ static int cmp_nla_nh6(struct seg6_local_lwt *a, struct seg6_local_lwt *b) return memcmp(&a->nh6, &b->nh6, sizeof(struct in6_addr)); } -static int parse_nla_iif(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_iif(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { slwt->iif = nla_get_u32(attrs[SEG6_LOCAL_IIF]); @@ -1337,7 +1343,8 @@ static int cmp_nla_iif(struct seg6_local_lwt *a, struct seg6_local_lwt *b) return 0; } -static int parse_nla_oif(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_oif(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { slwt->oif = nla_get_u32(attrs[SEG6_LOCAL_OIF]); @@ -1367,7 +1374,8 @@ static const struct nla_policy bpf_prog_policy[SEG6_LOCAL_BPF_PROG_MAX + 1] = { .len = MAX_PROG_NAME }, }; -static int parse_nla_bpf(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_bpf(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct nlattr *tb[SEG6_LOCAL_BPF_PROG_MAX + 1]; struct bpf_prog *p; @@ -1445,7 +1453,8 @@ nla_policy seg6_local_counters_policy[SEG6_LOCAL_CNT_MAX + 1] = { }; static int parse_nla_counters(struct nlattr **attrs, - struct seg6_local_lwt *slwt) + struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct pcpu_seg6_local_counters __percpu *pcounters; struct nlattr *tb[SEG6_LOCAL_CNT_MAX + 1]; @@ -1544,7 +1553,8 @@ static void destroy_attr_counters(struct seg6_local_lwt *slwt) } struct seg6_action_param { - int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt); + int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack); int (*put)(struct sk_buff *skb, struct seg6_local_lwt *slwt); int (*cmp)(struct seg6_local_lwt *a, struct seg6_local_lwt *b); @@ -1637,7 +1647,8 @@ static void destroy_attrs(struct seg6_local_lwt *slwt) } static int parse_nla_optional_attrs(struct nlattr **attrs, - struct seg6_local_lwt *slwt) + struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct seg6_action_desc *desc = slwt->desc; unsigned long parsed_optattrs = 0; @@ -1653,7 +1664,7 @@ static int parse_nla_optional_attrs(struct nlattr **attrs, */ param = &seg6_action_params[i]; - err = param->parse(attrs, slwt); + err = param->parse(attrs, slwt, extack); if (err < 0) goto parse_optattrs_err; @@ -1706,7 +1717,8 @@ static void seg6_local_lwtunnel_destroy_state(struct seg6_local_lwt *slwt) ops->destroy_state(slwt); } -static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt) +static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) { struct seg6_action_param *param; struct seg6_action_desc *desc; @@ -1750,14 +1762,14 @@ static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt) param = &seg6_action_params[i]; - err = param->parse(attrs, slwt); + err = param->parse(attrs, slwt, extack); if (err < 0) goto parse_attrs_err; } } /* parse the optional attributes, if any */ - err = parse_nla_optional_attrs(attrs, slwt); + err = parse_nla_optional_attrs(attrs, slwt, extack); if (err < 0) goto parse_attrs_err; @@ -1801,7 +1813,7 @@ static int seg6_local_build_state(struct net *net, struct nlattr *nla, slwt = seg6_local_lwtunnel(newts); slwt->action = nla_get_u32(tb[SEG6_LOCAL_ACTION]); - err = parse_nla_action(tb, slwt); + err = parse_nla_action(tb, slwt, extack); if (err < 0) goto out_free; From patchwork Sat Jun 11 10:47:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Mayer X-Patchwork-Id: 12878439 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C569C43334 for ; Sat, 11 Jun 2022 10:48:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232550AbiFKKsk (ORCPT ); Sat, 11 Jun 2022 06:48:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230410AbiFKKsg (ORCPT ); Sat, 11 Jun 2022 06:48:36 -0400 Received: from smtp.uniroma2.it (smtp.uniroma2.it [160.80.6.16]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6479330561; Sat, 11 Jun 2022 03:48:33 -0700 (PDT) Received: from localhost.localdomain ([160.80.103.126]) by smtp-2015.uniroma2.it (8.14.4/8.14.4/Debian-8) with ESMTP id 25BAm7gM007213 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Sat, 11 Jun 2022 12:48:09 +0200 From: Andrea Mayer To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Stefano Salsano , Paolo Lungaroni , Ahmed Abdelsalam , Andrea Mayer Subject: [net-next v1 2/2] seg6: add NEXT-C-SID support for SRv6 End behavior Date: Sat, 11 Jun 2022 12:47:50 +0200 Message-Id: <20220611104750.2724-3-andrea.mayer@uniroma2.it> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220611104750.2724-1-andrea.mayer@uniroma2.it> References: <20220611104750.2724-1-andrea.mayer@uniroma2.it> MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 0.100.0 at smtp-2015 X-Virus-Status: Clean Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The NEXT-C-SID mechanism described in [1] offers the possibility of encoding several SRv6 segments within a single 128 bit SID address. Such a SID address is called a Compressed SID (C-SID) container. In this way, the length of the SID List can be drastically reduced. A SID instantiated with the NEXT-C-SID flavor considers an IPv6 address logically structured in three main blocks: i) Locator-Block; ii) Locator-Node Function; iii) Argument. C-SID container +------------------------------------------------------------------+ | Locator-Block |Loc-Node| Argument | | |Function| | +------------------------------------------------------------------+ <--------- B -----------> <- NF -> <------------- A ---------------> (i) The Locator-Block can be any IPv6 prefix available to the provider; (ii) The Locator-Node Function represents the node and the function to be triggered when a packet is received on the node; (iii) The Argument carries the remaining C-SIDs in the current C-SID container. The NEXT-C-SID mechanism relies on the "flavors" framework defined in [2]. The flavors represent additional operations that can modify or extend a subset of the existing behaviors. This patch introduces the support for flavors in SRv6 End behavior implementing the NEXT-C-SID one. An SRv6 End behavior with NEXT-C-SID flavor works as an End behavior but it is capable of processing the compressed SID List encoded in C-SID containers. An SRv6 End behavior with NEXT-C-SID flavor can be configured to support user-provided Locator-Block and Locator-Node Function lengths. In this implementation, such lengths must be evenly divisible by 8 (i.e. must be byte-aligned), otherwise the kernel informs the user about invalid values with a meaningful error code and message through netlink_ext_ack. If Locator-Block and/or Locator-Node Function lengths are not provided by the user during configuration of an SRv6 End behavior instance with NEXT-C-SID flavor, the kernel will choose their default values i.e., 32-bit Locator-Block and 16-bit Locator-Node Function. [1] - https://datatracker.ietf.org/doc/html/draft-ietf-spring-srv6-srh-compression [2] - https://datatracker.ietf.org/doc/html/rfc8986 Signed-off-by: Andrea Mayer Reported-by: kernel test robot --- include/uapi/linux/seg6_local.h | 24 +++ net/ipv6/seg6_local.c | 311 +++++++++++++++++++++++++++++++- 2 files changed, 332 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/seg6_local.h b/include/uapi/linux/seg6_local.h index 332b18f318f8..7919940c84d0 100644 --- a/include/uapi/linux/seg6_local.h +++ b/include/uapi/linux/seg6_local.h @@ -28,6 +28,7 @@ enum { SEG6_LOCAL_BPF, SEG6_LOCAL_VRFTABLE, SEG6_LOCAL_COUNTERS, + SEG6_LOCAL_FLAVORS, __SEG6_LOCAL_MAX, }; #define SEG6_LOCAL_MAX (__SEG6_LOCAL_MAX - 1) @@ -110,4 +111,27 @@ enum { #define SEG6_LOCAL_CNT_MAX (__SEG6_LOCAL_CNT_MAX - 1) +/* SRv6 End* Flavor attributes */ +enum { + SEG6_LOCAL_FLV_UNSPEC, + SEG6_LOCAL_FLV_OPERATION, + SEG6_LOCAL_FLV_LCBLOCK_LEN, + SEG6_LOCAL_FLV_LCNODE_FN_LEN, + __SEG6_LOCAL_FLV_MAX, +}; + +#define SEG6_LOCAL_FLV_MAX (__SEG6_LOCAL_FLV_MAX - 1) + +/* Designed flavor operations for SRv6 End* Behavior */ +enum { + SEG6_LOCAL_FLV_OP_UNSPEC, + SEG6_LOCAL_FLV_OP_PSP, + SEG6_LOCAL_FLV_OP_USP, + SEG6_LOCAL_FLV_OP_USD, + SEG6_LOCAL_FLV_OP_NEXT_CSID, + __SEG6_LOCAL_FLV_OP_MAX +}; + +#define SEG6_LOCAL_FLV_OP_MAX (__SEG6_LOCAL_FLV_OP_MAX - 1) + #endif diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 5ea51ee2ef71..eb31c6c838e3 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -73,6 +73,39 @@ struct bpf_lwt_prog { char *name; }; +/* default length values (expressed in bits) for both Locator-Block and + * Locator-Node Function. + * + * Both SEG6_LOCAL_LCBLOCK_DLEN and SEG6_LOCAL_LCNODE_FN_DLEN *must* be: + * i) greater than 0; + * ii) evenly divisible by 8. In other terms, the lengths of the + * Locator-Block and Locator-Node Function must be byte-aligned (we can + * relax this constraint in the future if really needed). + * + * Moreover, a third condition must hold: + * iii) SEG6_LOCAL_LCBLOCK_DLEN + SEG6_LOCAL_LCNODE_FN_DLEN <= 128. + * + * The correctness of SEG6_LOCAL_LCBLOCK_DLEN and SEG6_LOCAL_LCNODE_FN_DLEN + * values are checked during the kernel compilation. If the compilation stops, + * check the value of these parameters to see if they meet conditions (i), (ii) + * and (iii). + */ +#define SEG6_LOCAL_LCBLOCK_DLEN 32 +#define SEG6_LOCAL_LCNODE_FN_DLEN 16 + +/* Supported Flavor operations are reported in this bitmask */ +#define SEG6_LOCAL_FLV_SUPP_OPS (BIT(SEG6_LOCAL_FLV_OP_NEXT_CSID)) + +struct seg6_flavors_info { + /* Flavor operations */ + __u32 flv_ops; + + /* Locator-Block length, expressed in bits */ + __u8 lcblock_len; + /* Locator-Node Function length, expressed in bits*/ + __u8 lcnode_func_len; +}; + enum seg6_end_dt_mode { DT_INVALID_MODE = -EINVAL, DT_LEGACY_MODE = 0, @@ -136,6 +169,8 @@ struct seg6_local_lwt { #ifdef CONFIG_NET_L3_MASTER_DEV struct seg6_end_dt_info dt_info; #endif + struct seg6_flavors_info flv_info; + struct pcpu_seg6_local_counters __percpu *pcpu_counters; int headroom; @@ -270,8 +305,50 @@ int seg6_lookup_nexthop(struct sk_buff *skb, return seg6_lookup_any_nexthop(skb, nhaddr, tbl_id, false); } -/* regular endpoint function */ -static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt) +static __u8 seg6_flv_lcblock_octects(const struct seg6_flavors_info *finfo) +{ + return finfo->lcblock_len >> 3; +} + +static __u8 seg6_flv_lcnode_func_octects(const struct seg6_flavors_info *finfo) +{ + return finfo->lcnode_func_len >> 3; +} + +static bool seg6_next_csid_is_arg_zero(const struct in6_addr *addr, + const struct seg6_flavors_info *finfo) +{ + __u8 fnc_octects = seg6_flv_lcnode_func_octects(finfo); + __u8 blk_octects = seg6_flv_lcblock_octects(finfo); + __u8 arg_octects; + int i; + + arg_octects = 16 - blk_octects - fnc_octects; + for (i = 0; i < arg_octects; ++i) { + if (addr->s6_addr[blk_octects + fnc_octects + i] != 0x00) + return false; + } + + return true; +} + +/* assume that DA.Argument length > 0 */ +static void seg6_next_csid_advance_arg(struct in6_addr *addr, + const struct seg6_flavors_info *finfo) +{ + __u8 fnc_octects = seg6_flv_lcnode_func_octects(finfo); + __u8 blk_octects = seg6_flv_lcblock_octects(finfo); + + /* advance DA.Argument */ + memmove((void *)&addr->s6_addr[blk_octects], + (const void *)&addr->s6_addr[blk_octects + fnc_octects], + 16 - blk_octects - fnc_octects); + + memset((void *)&addr->s6_addr[16 - fnc_octects], 0x00, fnc_octects); +} + +static int input_action_end_core(struct sk_buff *skb, + struct seg6_local_lwt *slwt) { struct ipv6_sr_hdr *srh; @@ -290,6 +367,38 @@ static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt) return -EINVAL; } +static int end_next_csid_core(struct sk_buff *skb, struct seg6_local_lwt *slwt) +{ + const struct seg6_flavors_info *finfo = &slwt->flv_info; + struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; + + if (seg6_next_csid_is_arg_zero(daddr, finfo)) + return input_action_end_core(skb, slwt); + + /* update DA */ + seg6_next_csid_advance_arg(daddr, finfo); + + seg6_lookup_nexthop(skb, NULL, 0); + + return dst_input(skb); +} + +static bool seg6_next_csid_enabled(__u32 fops) +{ + return fops & BIT(SEG6_LOCAL_FLV_OP_NEXT_CSID); +} + +/* regular endpoint function */ +static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt) +{ + const struct seg6_flavors_info *finfo = &slwt->flv_info; + + if (seg6_next_csid_enabled(finfo->flv_ops)) + return end_next_csid_core(skb, slwt); + + return input_action_end_core(skb, slwt); +} + /* regular endpoint, and forward to specified nexthop */ static int input_action_end_x(struct sk_buff *skb, struct seg6_local_lwt *slwt) { @@ -952,7 +1061,8 @@ static struct seg6_action_desc seg6_action_table[] = { { .action = SEG6_LOCAL_ACTION_END, .attrs = 0, - .optattrs = SEG6_F_LOCAL_COUNTERS, + .optattrs = SEG6_F_LOCAL_COUNTERS | + SEG6_F_ATTR(SEG6_LOCAL_FLAVORS), .input = input_action_end, }, { @@ -1133,6 +1243,7 @@ static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = { [SEG6_LOCAL_OIF] = { .type = NLA_U32 }, [SEG6_LOCAL_BPF] = { .type = NLA_NESTED }, [SEG6_LOCAL_COUNTERS] = { .type = NLA_NESTED }, + [SEG6_LOCAL_FLAVORS] = { .type = NLA_NESTED }, }; static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt, @@ -1552,6 +1663,190 @@ static void destroy_attr_counters(struct seg6_local_lwt *slwt) free_percpu(slwt->pcpu_counters); } +static const +struct nla_policy seg6_local_flavors_policy[SEG6_LOCAL_FLV_MAX + 1] = { + [SEG6_LOCAL_FLV_OPERATION] = { .type = NLA_U32 }, + [SEG6_LOCAL_FLV_LCBLOCK_LEN] = { .type = NLA_U8 }, + [SEG6_LOCAL_FLV_LCNODE_FN_LEN] = { .type = NLA_U8 }, +}; + +/* check whether the lengths of the Locator-Block and Locator-Node Function + * are compatible with the dimension of a C-SID container. + */ +static int seg6_chk_next_csid_cfg(__u8 block_len, __u8 func_len) +{ + /* Locator-Block and Locator-Node Function cannot exceed 128 bits */ + if (block_len + func_len > 128) + return -EINVAL; + + /* Locator-Block length must be greater than zero and evenly divisible + * by 8. There must be room for a Locator-Node Function, at least. + */ + if (block_len < 8 || block_len > 120 || (block_len & 0x07)) + return -EINVAL; + + /* Locator-Node Function length must be greater than zero and evenly + * divisible by 8. There must be room for the Locator-Block. + */ + if (func_len < 8 || func_len > 120 || (func_len & 0x07)) + return -EINVAL; + + return 0; +} + +static int seg6_parse_nla_next_csid_cfg(struct nlattr **tb, + struct seg6_flavors_info *finfo, + struct netlink_ext_ack *extack) +{ + __u8 func_len = SEG6_LOCAL_LCNODE_FN_DLEN; + __u8 block_len = SEG6_LOCAL_LCBLOCK_DLEN; + int rc; + + if (tb[SEG6_LOCAL_FLV_LCBLOCK_LEN]) + block_len = nla_get_u8(tb[SEG6_LOCAL_FLV_LCBLOCK_LEN]); + + if (tb[SEG6_LOCAL_FLV_LCNODE_FN_LEN]) + func_len = nla_get_u8(tb[SEG6_LOCAL_FLV_LCNODE_FN_LEN]); + + rc = seg6_chk_next_csid_cfg(block_len, func_len); + if (rc < 0) { + NL_SET_ERR_MSG(extack, + "Invalid Locator Block/Node Function lengths"); + return rc; + } + + finfo->lcblock_len = block_len; + finfo->lcnode_func_len = func_len; + + return 0; +} + +static int parse_nla_flavors(struct nlattr **attrs, struct seg6_local_lwt *slwt, + struct netlink_ext_ack *extack) +{ + struct seg6_flavors_info *finfo = &slwt->flv_info; + struct nlattr *tb[SEG6_LOCAL_FLV_MAX + 1]; + unsigned long fops; + int rc; + + rc = nla_parse_nested_deprecated(tb, SEG6_LOCAL_FLV_MAX, + attrs[SEG6_LOCAL_FLAVORS], + seg6_local_flavors_policy, NULL); + if (rc < 0) + return rc; + + /* this attribute MUST always be present since it represents the Flavor + * operation(s) to carry out. + */ + if (!tb[SEG6_LOCAL_FLV_OPERATION]) + return -EINVAL; + + fops = nla_get_u32(tb[SEG6_LOCAL_FLV_OPERATION]); + if (~SEG6_LOCAL_FLV_SUPP_OPS & fops) { + NL_SET_ERR_MSG(extack, "Unsupported Flavor operation(s)"); + return -EOPNOTSUPP; + } + + finfo->flv_ops = fops; + + if (seg6_next_csid_enabled(fops)) { + /* Locator-Block and Locator-Node Function lengths can be + * provided by the user space. If not, default values are going + * to be applied. + */ + rc = seg6_parse_nla_next_csid_cfg(tb, finfo, extack); + if (rc < 0) + return rc; + } + + return 0; +} + +static int seg6_fill_nla_next_csid_cfg(struct sk_buff *skb, + struct seg6_flavors_info *finfo) +{ + if (nla_put_u8(skb, SEG6_LOCAL_FLV_LCBLOCK_LEN, finfo->lcblock_len)) + return -EMSGSIZE; + + if (nla_put_u8(skb, SEG6_LOCAL_FLV_LCNODE_FN_LEN, + finfo->lcnode_func_len)) + return -EMSGSIZE; + + return 0; +} + +static int put_nla_flavors(struct sk_buff *skb, struct seg6_local_lwt *slwt) +{ + struct seg6_flavors_info *finfo = &slwt->flv_info; + __u32 fops = finfo->flv_ops; + struct nlattr *nest; + int rc; + + nest = nla_nest_start(skb, SEG6_LOCAL_FLAVORS); + if (!nest) + return -EMSGSIZE; + + if (nla_put_u32(skb, SEG6_LOCAL_FLV_OPERATION, fops)) { + rc = -EMSGSIZE; + goto err; + } + + if (seg6_next_csid_enabled(fops)) { + rc = seg6_fill_nla_next_csid_cfg(skb, finfo); + if (rc < 0) + goto err; + } + + return nla_nest_end(skb, nest); + +err: + nla_nest_cancel(skb, nest); + return rc; +} + +static int seg6_cmp_nla_next_csid_cfg(struct seg6_flavors_info *finfo_a, + struct seg6_flavors_info *finfo_b) +{ + if (finfo_a->lcblock_len != finfo_b->lcblock_len) + return 1; + + if (finfo_a->lcnode_func_len != finfo_b->lcnode_func_len) + return 1; + + return 0; +} + +static int cmp_nla_flavors(struct seg6_local_lwt *a, struct seg6_local_lwt *b) +{ + struct seg6_flavors_info *finfo_a = &a->flv_info; + struct seg6_flavors_info *finfo_b = &b->flv_info; + + if (finfo_a->flv_ops != finfo_b->flv_ops) + return 1; + + if (seg6_next_csid_enabled(finfo_a->flv_ops)) { + if (seg6_cmp_nla_next_csid_cfg(finfo_a, finfo_b)) + return 1; + } + + return 0; +} + +static int encap_size_flavors(struct seg6_local_lwt *slwt) +{ + struct seg6_flavors_info *finfo = &slwt->flv_info; + int nlsize; + + nlsize = nla_total_size(0) + /* nest SEG6_LOCAL_FLAVORS */ + nla_total_size(4); /* SEG6_LOCAL_FLV_OPERATION */ + + if (seg6_next_csid_enabled(finfo->flv_ops)) + nlsize += nla_total_size(1) + /* SEG6_LOCAL_FLV_LCBLOCK_LEN */ + nla_total_size(1); /* SEG6_LOCAL_FLV_LCNODE_FN_LEN */ + + return nlsize; +} + struct seg6_action_param { int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt, struct netlink_ext_ack *extack); @@ -1604,6 +1899,10 @@ static struct seg6_action_param seg6_action_params[SEG6_LOCAL_MAX + 1] = { .put = put_nla_counters, .cmp = cmp_nla_counters, .destroy = destroy_attr_counters }, + + [SEG6_LOCAL_FLAVORS] = { .parse = parse_nla_flavors, + .put = put_nla_flavors, + .cmp = cmp_nla_flavors }, }; /* call the destroy() callback (if available) for each set attribute in @@ -1917,6 +2216,9 @@ static int seg6_local_get_encap_size(struct lwtunnel_state *lwt) /* SEG6_LOCAL_CNT_ERRORS */ nla_total_size_64bit(sizeof(__u64)); + if (attrs & SEG6_F_ATTR(SEG6_LOCAL_FLAVORS)) + nlsize += encap_size_flavors(slwt); + return nlsize; } @@ -1972,6 +2274,9 @@ int __init seg6_local_init(void) */ BUILD_BUG_ON(SEG6_LOCAL_MAX + 1 > BITS_PER_TYPE(unsigned long)); + BUILD_BUG_ON(seg6_chk_next_csid_cfg(SEG6_LOCAL_LCBLOCK_DLEN, + SEG6_LOCAL_LCNODE_FN_DLEN) != 0); + return lwtunnel_encap_add_ops(&seg6_local_ops, LWTUNNEL_ENCAP_SEG6_LOCAL); }