Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

server:
        verbosity: 3
        edns-tcp-keepalive: yes
        edns-tcp-keepalive-timeout: 30000 # Hardwired to this in fake_event.c
stub-zone:
        name: "."
        stub-addr: 193.0.14.129         # K.ROOT-SERVERS.NET.
CONFIG_END

SCENARIO_BEGIN TCP Keepalive

RANGE_BEGIN 0 100

        ADDRESS 193.0.14.129

        ENTRY_BEGIN
                MATCH opcode qtype qname
                ADJUST copy_id
                REPLY QR NOERROR
                SECTION QUESTION
                        . IN NS
                SECTION ANSWER
                        . IN NS K.ROOT-SERVERS.NET.
                SECTION ADDITIONAL
                        K.ROOT-SERVERS.NET.     IN      A       193.0.14.129
        ENTRY_END

RANGE_END

;; ----------------------------------------

STEP 1 QUERY

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY RD
        SECTION QUESTION
                www.example.com. IN A
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        00 0b           ; Opcode 11
                        00 02           ; Length 2
                        00 ff           ; Timeout
                HEX_EDNSDATA_END
     ENTRY_END

STEP 10 CHECK_ANSWER

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY RD FORMERR
        SECTION QUESTION
                www.example.com. IN A
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        ; Empty
                HEX_EDNSDATA_END
     ENTRY_END

STEP 20 QUERY

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY RD
        SECTION QUESTION
                . IN NS
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        00 0b           ; Opcode 11
                        00 00           ; Length 0
                HEX_EDNSDATA_END
     ENTRY_END

STEP 30 CHECK_ANSWER

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY QR RD RA NOERROR
        SECTION QUESTION
                . IN NS
        SECTION ANSWER
                . IN NS K.ROOT-SERVERS.NET.
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        00 0b           ; Opcode 11
                        00 02           ; Length 2
                        01 2c           ; 30s = 300 10th secs
                HEX_EDNSDATA_END
                K.ROOT-SERVERS.NET.     IN      A       193.0.14.129
     ENTRY_END

; Check that a subsequent query on the connection without keepalive will
; generate a keepalive reply because we've already seen one.

STEP 40 QUERY

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY RD
        SECTION QUESTION
                . IN NS
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        ; Empty
                HEX_EDNSDATA_END
     ENTRY_END

STEP 50 CHECK_ANSWER

     ENTRY_BEGIN
        MATCH TCP ednsdata
        REPLY QR RD RA NOERROR
        SECTION QUESTION
                . IN NS
        SECTION ANSWER
                . IN NS K.ROOT-SERVERS.NET.
        SECTION ADDITIONAL
                HEX_EDNSDATA_BEGIN
                        00 0b           ; Opcode 11
                        00 02           ; Length 2
                        01 2c           ; 30s = 300 10th secs
                HEX_EDNSDATA_END
                K.ROOT-SERVERS.NET.     IN      A       193.0.14.129
     ENTRY_END

SCENARIO_END