From 9d5e303a998e4618d492c9d0befb09e3cd3d746b Mon Sep 17 00:00:00 2001 From: Vadim Kochan Date: Thu, 1 Jun 2017 13:12:28 +0300 Subject: trafgen: l7: Add DNS header generation API Add trafgen_l7.c module with DNS proto header generation with support of filling DNS query/answer/authority/additional sections as sub headers. Introcuded new concept as 'sub header' which is needed to easy handle DNS sections which might be added on-demand, and to simplify using sub-header as regular header with a fields, offset, etc. There is a parent header which contains array of pointers of sub-headers, and the array is ordered as they are located in the parent header. The sub-headers mostly encapsulated by the parent header which 'knows' the semantic of them. The new proto_hdr->push_sub_header(...) callback was added to tell the parent header to push the sub-header's fields, sub-header also may have proto_ops which must be filled by the parent. This sub-header concept might be used in the future if it will be needed to support DHCP, WLAN headers. There are 4 kinds of DNS sub-headers - query, answer, authority, additional. 'id' of each sub-header is used to only differentiate these types of sections. These sections have strict order inside DNS header, and there was added the proto_hdr_move_sub_header(...) to sort them in required order. Actually there are only 2 proto_hdr's which describes 4 DNS sections - query & rrecord, because rrecord covers another 3 - answer, auhority, additional which have the same layout. Signed-off-by: Vadim Kochan Signed-off-by: Tobias Klauser --- trafgen_l7.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 trafgen_l7.h (limited to 'trafgen_l7.h') diff --git a/trafgen_l7.h b/trafgen_l7.h new file mode 100644 index 0000000..cf19fa4 --- /dev/null +++ b/trafgen_l7.h @@ -0,0 +1,45 @@ +#ifndef TRAFGEN_L7_H +#define TRAFGEN_L7_H + +enum dns_field { + DNS_ID, + DNS_QR, + DNS_OPCODE, + DNS_AA, + DNS_TC, + DNS_RD, + DNS_RA, + DNS_ZERO, + DNS_RCODE, + DNS_QD_COUNT, + DNS_AN_COUNT, + DNS_NS_COUNT, + DNS_AR_COUNT, +}; + +enum dns_header { + DNS_UNDEF_HDR, + DNS_QUERY_HDR, + DNS_ANSWER_HDR, + DNS_AUTH_HDR, + DNS_ADD_HDR, +}; + +enum dns_query_field { + DNS_QUERY_NAME, + DNS_QUERY_TYPE, + DNS_QUERY_CLASS, +}; + +enum dns_rrecord_field { + DNS_RRECORD_NAME, + DNS_RRECORD_TYPE, + DNS_RRECORD_CLASS, + DNS_RRECORD_TTL, + DNS_RRECORD_LEN, + DNS_RRECORD_DATA, +}; + +extern void protos_l7_init(void); + +#endif /* TRAFGEN_L7_H */ -- cgit v1.2.3-54-g00ecf