also made sure that all old dns binaries work (SLES 11, FreeBSD 9)

This commit is contained in:
Dirk 2017-02-11 14:01:51 +01:00
parent 386aa92448
commit 8dabc28280

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@ -11492,41 +11492,64 @@ get_aaaa_record() {
# RFC6844: DNS Certification Authority Authorization (CAA) Resource Record
# arg1: domain to check for
get_caa_rr_record() {
local caa=""
local raw_caa=""
local caa_flag
local -i len_caa_property
local caa_property_name
local caa_property_value
local saved_openssl_conf="$OPENSSL_CONF"
# if there's a type257 record there are two output formats here, mostly depending on age of distribution
# rougly that's the difference between text and binary format
# 1) 'google.com has CAA record 0 issue "symantec.com"'
# 2) 'google.com has TYPE257 record \# 19 0005697373756573796D616E7465632E636F6D'
# for dig +short the output always starts with '0 issue [..]' or '\# 19 [..]' so we normalize thereto to keep caa_flag, caa_property
# caa_property then has key/value pairs, see https://tools.ietf.org/html/rfc6844#section-3
OPENSSL_CONF=""
if which dig &> /dev/null; then
caa="$(dig $1 type257 +short | awk '{ print $3 }')"
raw_caa="$(dig $1 type257 +short)"
# empty if no CAA record
elif which host &> /dev/null; then
caa="$(host -t type257 $1)"
if grep -wq issue <<< "$caa" && grep -wvq "has no CAA" <<< "$caa"; then
caa="$(awk '/issue/ { print $NF }' <<< "$caa")"
raw_caa="$(host -t type257 $1)"
if egrep -wvq "has no CAA|has no TYPE257" <<< "$raw_caa"; then
raw_caa="$(sed -e 's/^.*has CAA record //' -e 's/^.*has TYPE257 record //' <<< "$raw_caa")"
fi
elif which nslookup &> /dev/null; then
caa="$(nslookup -type=type257 $1)"
if grep -wq issue <<< "$caa" && grep -wvq "No answer" <<< "$caa"; then
caa="$(awk '/issue/ { print $NF }' <<< "$caa")"
raw_caa="$(nslookup -type=type257 $1 | grep -w rdata_257)"
if [[ -n "$raw_caa" ]]; then
raw_caa="$(sed 's/^.*rdata_257 = //' <<< "$raw_caa")"
fi
else
return 1
# No dig, host, or nslookup --> complaint was elsewhere already and except for one which has drill only we don't get here
fi
OPENSSL_CONF="$saved_openssl_conf" # see https://github.com/drwetter/testssl.sh/issues/134
debugme echo $raw_caa
# try to convert old return values
if [[ "$caa" =~ ^[A-F0-9]+$ ]]; then
caa=${caa:4:100} # ignore the first 4 bytes
caa=$(hex2ascii "$caa" | sed 's/^issue//g')
# '# 19' for google.com is the tag length probably --> we use this also to identify the binary format
if [[ "$raw_caa" =~ \#\ [0-9][0-9]\ [A-F0-9]+$ ]]; then
raw_caa=$(awk '{ print $NF }' <<< $raw_caa) # caa_length would be awk '{ print $(NF-1) }' but we don't need it
if [[ "${raw_caa:0:2}" == "00" ]]; then # probably the flag
caa_flag="0"
len_caa_property=${raw_caa:2:2} # implicit type casting, for google we have 05 here as a string
len_caa_property=$((len_caa_property*2)) # =>word! Now get name from 4th and value from 4th+len position...
caa_property_name=$(hex2ascii ${raw_caa:4:$len_caa_property})
caa_property_value=$(hex2ascii ${raw_caa:$((4+len_caa_property)):100})
else
outln "please report unknown CAA flag $caa_flag @ $NODE"
fi
elif grep -q '"' <<< $raw_caa; then
raw_caa=${raw_caa//\"/} # strip " first. Now we should have flag, name, value
caa_flag=$(awk '{ print $1 }' <<< $raw_caa)
caa_property_name=$(awk '{ print $2 }' <<< $raw_caa)
caa_property_value=$(awk '{ print $3 }' <<< $raw_caa)
else
caa=${caa//\"/} # strip "
# no caa record
return 1
fi
echo "$caa"
echo "$caa_property_name: $caa_property_value"
# to do:
# 1: check old binaries whether they support this record at all
# done (2: check whether hexstring is returned and deal with it)
# 3: check more than domainname, see https://tools.ietf.org/html/rfc6844#section-3
# 4: check whether $1 is a CNAME and take this
# 5: query with drill
return 0