From: Willy Tarreau Date: Wed, 26 Apr 2023 07:40:23 +0000 (+0200) Subject: DEV: h2: add a script "mkhdr" to build h2 frames from scratch X-Git-Tag: v2.8-dev9~38 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=78bb934607b2ed35df1a491faebe5a0d68f5e405;p=thirdparty%2Fhaproxy.git DEV: h2: add a script "mkhdr" to build h2 frames from scratch It's a real pain to try to trigger certain edge cases in h2, so let's write a simple tool aiming at creating frames. --- diff --git a/dev/h2/mkhdr.sh b/dev/h2/mkhdr.sh new file mode 100755 index 0000000000..350514c88c --- /dev/null +++ b/dev/h2/mkhdr.sh @@ -0,0 +1,138 @@ +#!/usr/bin/env bash + +# Usage: mkhdr -l -t -f -sid > hdr.bin +# All fields are optional. 0 assumed when absent. + +USAGE=\ +"Usage: %s [-l ] [-t ] [-f ] [-i ] > hdr.bin + Numbers are decimal or 0xhex. Not set=0. + +Supported symbolic types (case insensitive prefix match): + DATA (0x00) PUSH_PROMISE (0x05) + HEADERS (0x01) PING (0x06) + PRIORITY (0x02) GOAWAY (0x07) + RST_STREAM (0x03) WINDOW_UPDATE (0x08) + SETTINGS (0x04) CONTINUATION (0x09) + +Supported symbolic flags (case insensitive prefix match): + ES (0x01) PAD (0x08) + EH (0x04) PRIO (0x20) + +" + +LEN= +TYPE= +FLAGS= +ID= + +die() { + [ "$#" -eq 0 ] || echo "$*" >&2 + exit 1 +} + +quit() { + [ "$#" -eq 0 ] || echo "$*" + exit 0 +} + +# print usage with $1 as the cmd name +usage() { + printf "$USAGE" "$1"; +} + +# Send frame made of $1 $2 $3 $4 to stdout. +# Usage: mkframe +mkframe() { + local L="${1:-0}" + local T="${2:-0}" + local F="${3:-0}" + local I="${4:-0}" + local t f + + # get the first match in this order + for t in DATA:0x00 HEADERS:0x01 RST_STREAM:0x03 SETTINGS:0x04 PING:0x06 \ + GOAWAY:0x07 WINDOW_UPDATE:0x08 CONTINUATION:0x09 PRIORITY:0x02 \ + PUSH_PROMISE:0x05; do + if [ -z "${t##${T^^*}*}" ]; then + T="${t##*:}" + break + fi + done + + if [ -n "${T##[0-9]*}" ]; then + echo "Unknown type '$T'" >&2 + usage "${0##*}" + die + fi + + # get the first match in this order + for f in ES:0x01 EH:0x04 PAD:0x08 PRIO:0x20; do + if [ -z "${f##${F^^*}*}" ]; then + F="${f##*:}" + fi + done + + if [ -n "${F##[0-9]*}" ]; then + echo "Unknown type '$T'" >&2 + usage "${0##*}" + die + fi + + L=$(( L )); T=$(( T )); F=$(( F )); I=$(( I )) + + L0=$(( (L >> 16) & 255 )); L0=$(printf "%02x" $L0) + L1=$(( (L >> 8) & 255 )); L1=$(printf "%02x" $L1) + L2=$(( (L >> 0) & 255 )); L2=$(printf "%02x" $L2) + + T0=$(( (T >> 0) & 255 )); T0=$(printf "%02x" $T0) + F0=$(( (F >> 0) & 255 )); F0=$(printf "%02x" $F0) + + I0=$(( (I >> 24) & 127 )); I0=$(printf "%02x" $I0) + I1=$(( (I >> 16) & 255 )); I1=$(printf "%02x" $I1) + I2=$(( (I >> 8) & 255 )); I2=$(printf "%02x" $I2) + I3=$(( (I >> 0) & 255 )); I3=$(printf "%02x" $I3) + + printf "\x$L0\x$L1\x$L2\x$T0\x$F0\x$I0\x$I1\x$I2\x$I3" +} + +## main + +if [ $# -le 1 ]; then + usage "${0##*}" + die +fi + +while [ -n "$1" -a -z "${1##-*}" ]; do + case "$1" in + -l) LEN="$2" ; shift 2 ;; + -t) TYPE="$2" ; shift 2 ;; + -f) FLAGS="$2" ; shift 2 ;; + -i) ID="$2" ; shift 2 ;; + -h|--help) usage "${0##*}"; quit;; + *) usage "${0##*}"; die ;; + esac +done + +if [ $# -gt 0 ]; then + usage "${0##*}" + die +fi + +# default values for LEN and ID +LEN=${LEN:-0}; +if [ -n "${LEN##[0-9]*}" ]; then + echo "Unparsable length '$LEN'" >&2 + usage "${0##*}" + die +fi + +ID=${ID:-0}; +if [ -n "${ID##[0-9]*}" ]; then + echo "Unparsable stream ID '$ID'" >&2 + usage "${0##*}" + die +fi + +mkframe "$LEN" "$TYPE" "$FLAGS" "$ID" + +exit 0