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jagath_311361's avatar
jagath_311361
Icon for Nimbostratus rankNimbostratus
Jul 26, 2018

HMAC Authentication using F5

We are trying to use the below iRule, as mentioned in the link https://devcentral.f5.com/codeshare/akamai-g20-header-authentication, which apparently is not working as the CRYTO::sign returns a hash ...
application delivery
iRules
iRulesLX
Niels_van_Sluis's avatar
Niels_van_Sluis
Icon for MVP rankMVP
Jul 27, 2018

Like you mentioned, the 

CRYPTO:sign
returns a binary. You need to convert this to a hexidecimal string. The iRule below works for me.

when HTTP_REQUEST {

if {[HTTP::header exists "X-Akamai-G2O-Auth-Data"] && [HTTP::header exists "X-Akamai-G2O-Auth-Sign"]} {

set shared secret here
set secret_key "pass" 
set data "[HTTP::header value "X-Akamai-G2O-Auth-Data"][HTTP::path]"
set signature "[HTTP::header value "X-Akamai-G2O-Auth-Sign"]"
set signed_data_binary [CRYPTO::sign -alg hmac-sha256 -key $secret_key $data]

binary scan $signed_data_binary H* signed_data_hex

if { $signed_data_hex eq $signature } {
log local0. "Signatures match"
}
}
}