From a7e02fe7984a721ae1240c415ec7d1e73ccc5dbd Mon Sep 17 00:00:00 2001 From: Ahmed Abdelsalam Date: Tue, 27 Feb 2018 11:04:14 +0100 Subject: src: Adding support for segment routing header 'srh' Segment Routing Header "SRH" is new type of IPv6 Routing extension header (type 4). SRH contains a list of segments (each is represented as an IPv6 address) to be visited by packets during the journey from source to destination. The SRH specification are defined in the below IETF SRH draft. https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-07 Signed-off-by: Ahmed Abdelsalam Signed-off-by: Pablo Neira Ayuso --- include/exthdr.h | 9 +++++++++ include/headers.h | 12 ++++++++++++ src/exthdr.c | 23 +++++++++++++++++++++++ src/parser_bison.y | 26 +++++++++++++++++++++++--- src/scanner.l | 4 ++++ 5 files changed, 71 insertions(+), 3 deletions(-) diff --git a/include/exthdr.h b/include/exthdr.h index 06bf6285..32f99c9c 100644 --- a/include/exthdr.h +++ b/include/exthdr.h @@ -57,6 +57,14 @@ enum rt2_hdr_fields { RT2HDR_ADDR, }; +enum rt4_hdr_fields { + RT4HDR_INVALID, + RT4HDR_LASTENT, + RT4HDR_FLAGS, + RT4HDR_TAG, + RT4HDR_SID_1, +}; + enum frag_hdr_fields { FRAGHDR_INVALID, FRAGHDR_NEXTHDR, @@ -87,6 +95,7 @@ extern const struct exthdr_desc exthdr_hbh; extern const struct exthdr_desc exthdr_rt; extern const struct exthdr_desc exthdr_rt0; extern const struct exthdr_desc exthdr_rt2; +extern const struct exthdr_desc exthdr_rt4; extern const struct exthdr_desc exthdr_frag; extern const struct exthdr_desc exthdr_dst; extern const struct exthdr_desc exthdr_mh; diff --git a/include/headers.h b/include/headers.h index 469d6740..3d564deb 100644 --- a/include/headers.h +++ b/include/headers.h @@ -112,6 +112,18 @@ struct ip6_mh { uint8_t data[0]; }; +/* Type 4 Routing header - well known as srh */ +struct ip6_rt4 { + uint8_t ip6r4_nxt; /* next header */ + uint8_t ip6r4_len; /* length in units of 8 octets */ + uint8_t ip6r4_type; /* always zero */ + uint8_t ip6r4_segleft; /* segments left */ + uint8_t ip6r4_last_entry; /* last entry */ + uint8_t ip6r4_flags; /* flags */ + uint16_t ip6r4_tag; /* tag */ + struct in6_addr ip6r4_segments[0]; /* SID list */ +}; + /* RFC 3775 */ #define IP6_MH_TYPE_BRR 0 /* Binding Refresh Request */ #define IP6_MH_TYPE_HOTI 1 /* HOTI Message */ diff --git a/src/exthdr.c b/src/exthdr.c index 3757f335..cbe0da86 100644 --- a/src/exthdr.c +++ b/src/exthdr.c @@ -101,6 +101,9 @@ struct expr *exthdr_expr_alloc(const struct location *loc, case 2: expr->exthdr.op = NFT_EXTHDR_OP_RT2; break; + case 4: + expr->exthdr.op = NFT_EXTHDR_OP_RT4; + break; } } return expr; @@ -165,6 +168,8 @@ void exthdr_init_raw(struct expr *expr, uint8_t type, expr->exthdr.desc = &exthdr_rt0; else if (op == NFT_EXTHDR_OP_RT2) expr->exthdr.desc = &exthdr_rt2; + else if (op == NFT_EXTHDR_OP_RT4) + expr->exthdr.desc = &exthdr_rt4; else if (type < array_size(exthdr_protocols)) expr->exthdr.desc = exthdr_protocols[type]; @@ -274,6 +279,24 @@ const struct exthdr_desc exthdr_rt0 = { }, }; +#define RT4_FIELD(__name, __member, __dtype) \ + HDR_TEMPLATE(__name, __dtype, struct ip6_rt4, __member) + +const struct exthdr_desc exthdr_rt4 = { + .name = "srh", + .type = IPPROTO_ROUTING, + .proto_key = 4, + .templates = { + [RT4HDR_LASTENT] = RT4_FIELD("last-entry", ip6r4_last_entry, &integer_type), + [RT4HDR_FLAGS] = RT4_FIELD("flags", ip6r4_flags, &integer_type), + [RT4HDR_TAG] = RT4_FIELD("tag", ip6r4_tag, &integer_type), + [RT4HDR_SID_1] = RT4_FIELD("sid[1]", ip6r4_segments[0], &ip6addr_type), + [RT4HDR_SID_1 + 1] = RT4_FIELD("sid[1]", ip6r4_segments[0], &ip6addr_type), + // ... + }, +}; + + #define RT_FIELD(__name, __member, __dtype) \ HDR_TEMPLATE(__name, __dtype, struct ip6_rthdr, __member) diff --git a/src/parser_bison.y b/src/parser_bison.y index 2ccaf9ab..5f84d794 100644 --- a/src/parser_bison.y +++ b/src/parser_bison.y @@ -364,8 +364,12 @@ int nft_lex(void *, void *, void *); %token RT "rt" %token RT0 "rt0" %token RT2 "rt2" +%token RT4 "srh" %token SEG_LEFT "seg-left" %token ADDR "addr" +%token LAST_ENT "last-entry" +%token TAG "tag" +%token SID "sid" %token HBH "hbh" @@ -674,9 +678,9 @@ int nft_lex(void *, void *, void *); %type hbh_hdr_expr frag_hdr_expr dst_hdr_expr %destructor { expr_free($$); } hbh_hdr_expr frag_hdr_expr dst_hdr_expr %type hbh_hdr_field frag_hdr_field dst_hdr_field -%type rt_hdr_expr rt0_hdr_expr rt2_hdr_expr -%destructor { expr_free($$); } rt_hdr_expr rt0_hdr_expr rt2_hdr_expr -%type rt_hdr_field rt0_hdr_field rt2_hdr_field +%type rt_hdr_expr rt0_hdr_expr rt2_hdr_expr rt4_hdr_expr +%destructor { expr_free($$); } rt_hdr_expr rt0_hdr_expr rt2_hdr_expr rt4_hdr_expr +%type rt_hdr_field rt0_hdr_field rt2_hdr_field rt4_hdr_field %type mh_hdr_expr %destructor { expr_free($$); } mh_hdr_expr %type mh_hdr_field @@ -3921,6 +3925,7 @@ exthdr_expr : hbh_hdr_expr | rt_hdr_expr | rt0_hdr_expr | rt2_hdr_expr + | rt4_hdr_expr | frag_hdr_expr | dst_hdr_expr | mh_hdr_expr @@ -3969,6 +3974,21 @@ rt2_hdr_expr : RT2 rt2_hdr_field rt2_hdr_field : ADDR { $$ = RT2HDR_ADDR; } ; +rt4_hdr_expr : RT4 rt4_hdr_field + { + $$ = exthdr_expr_alloc(&@$, &exthdr_rt4, $2); + } + ; + +rt4_hdr_field : LAST_ENT { $$ = RT4HDR_LASTENT; } + | FLAGS { $$ = RT4HDR_FLAGS; } + | TAG { $$ = RT4HDR_TAG; } + | SID '[' NUM ']' + { + $$ = RT4HDR_SID_1 + $3 - 1; + } + ; + frag_hdr_expr : FRAG frag_hdr_field { $$ = exthdr_expr_alloc(&@$, &exthdr_frag, $2); diff --git a/src/scanner.l b/src/scanner.l index ab10738b..1d8e8ba0 100644 --- a/src/scanner.l +++ b/src/scanner.l @@ -456,8 +456,12 @@ addrstring ({macaddr}|{ip4addr}|{ip6addr}) "rt" { return RT; } "rt0" { return RT0; } "rt2" { return RT2; } +"srh" { return RT4; } "seg-left" { return SEG_LEFT; } "addr" { return ADDR; } +"last-entry" { return LAST_ENT; } +"tag" { return TAG; } +"sid" { return SID; } "hbh" { return HBH; } -- cgit v1.2.3