proto: add protocol header fields filter and ordering for packet decoding

The next patch introduces packet decoding for tracing messages based on
the proto definitions. In order to provide a readable output, add a filter
to surpress uninteresting header fields and allow to specify and explicit
output order.

Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/include/proto.h b/include/proto.h
index c252a67d6ccdb81f5a58976b48ee7cd7e272d168..2a662a1a597a2e8dac05b57aacac867b760a7748 100644 (file)
--- a/include/proto.h
+++ b/include/proto.h
@@ -85,6 +85,11 @@ struct proto_desc {
                const struct proto_desc         *desc;
        }                               protocols[PROTO_UPPER_MAX];
        struct proto_hdr_template       templates[PROTO_HDRS_MAX];
+       struct {
+               uint8_t                         order[PROTO_HDRS_MAX];
+               uint32_t                        filter;
+       }                               format;
+
 };
 
 #define PROTO_LINK(__num, __desc)      { .num = (__num), .desc = (__desc), }

diff --git a/src/proto.c b/src/proto.c
index 329d9919fadcdbd559de2198da302a9c21d2de60..cecde0f4e6f23a37d7cb0eb4c7ae23bcd0676aaf 100644 (file)
--- a/src/proto.c
+++ b/src/proto.c
@@ -244,6 +244,12 @@ const struct proto_desc proto_ah = {
                [AHHDR_SPI]             = AHHDR_FIELD("spi", spi),
                [AHHDR_SEQUENCE]        = AHHDR_FIELD("sequence", seq_no),
        },
+       .format         = {
+               .order  = {
+                       AHHDR_SPI, AHHDR_HDRLENGTH, AHHDR_NEXTHDR,
+               },
+               .filter = (1 << AHHDR_RESERVED) | (1 << AHHDR_SEQUENCE)
+       },
 };
 
 /*
@@ -431,6 +437,11 @@ const struct proto_desc proto_tcp = {
                [TCPHDR_CHECKSUM]       = TCPHDR_FIELD("checksum", check),
                [TCPHDR_URGPTR]         = TCPHDR_FIELD("urgptr", urg_ptr),
        },
+       .format         = {
+               .filter = (1 << TCPHDR_SEQ) | (1 << TCPHDR_ACKSEQ) |
+                         (1 << TCPHDR_DOFF) | (1 << TCPHDR_RESERVED) |
+                         (1 << TCPHDR_URGPTR),
+       },
 };
 
 /*
@@ -535,6 +546,14 @@ const struct proto_desc proto_ip = {
                [IPHDR_SADDR]           = IPHDR_ADDR("saddr",           saddr),
                [IPHDR_DADDR]           = IPHDR_ADDR("daddr",           daddr),
        },
+       .format         = {
+               .order  = {
+                       IPHDR_SADDR, IPHDR_DADDR, IPHDR_TOS, IPHDR_TTL,
+                       IPHDR_ID, IPHDR_PROTOCOL, IPHDR_LENGTH,
+               },
+               .filter = (1 << IPHDR_VERSION)  | (1 << IPHDR_HDRLENGTH) |
+                         (1 << IPHDR_FRAG_OFF),
+       },
 };
 
 /*
@@ -631,6 +650,14 @@ const struct proto_desc proto_ip6 = {
                [IP6HDR_SADDR]          = IP6HDR_ADDR("saddr",          saddr),
                [IP6HDR_DADDR]          = IP6HDR_ADDR("daddr",          daddr),
        },
+       .format         = {
+               .order  = {
+                       IP6HDR_SADDR, IP6HDR_DADDR, IP6HDR_PRIORITY,
+                       IP6HDR_HOPLIMIT, IP6HDR_FLOWLABEL, IP6HDR_NEXTHDR,
+                       IP6HDR_LENGTH,
+               },
+               .filter = (1 << IP6HDR_VERSION),
+       },
 };
 
 /*
@@ -719,6 +746,10 @@ const struct proto_desc proto_arp = {
                [ARPHDR_PLN]            = ARPHDR_FIELD("plen", ar_pln),
                [ARPHDR_OP]             = ARPHDR_TYPE("operation", &arpop_type, ar_op),
        },
+       .format         = {
+               .filter = (1 << ARPHDR_HRD) | (1 << ARPHDR_PRO) |
+                         (1 << ARPHDR_HLN) | (1 << ARPHDR_PLN),
+       },
 };
 
 /*
@@ -818,6 +849,12 @@ const struct proto_desc proto_eth = {
                [ETHHDR_SADDR]          = ETHHDR_ADDR("saddr", ether_shost),
                [ETHHDR_TYPE]           = ETHHDR_TYPE("type", ether_type),
        },
+       .format         = {
+               .order  = {
+                       ETHHDR_SADDR, ETHHDR_DADDR, ETHHDR_TYPE,
+               },
+       },
+
 };
 
 /*