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bashcurltuya

Call to Tuya API via bash

I am having an hard time calling the Tuya API while using curl.

Tuya requires to generate a signature as following: HMAC-SHA256(client_id + t, secret). I built a small script that does exactly what Tuya asks. I have also double checked by trying to generate the signature using the same client_id, t and secret that are in their documentation as example, and the generated signature matches what the documentation says.

client_id is a pre-assigned value t is the timestamp in 13 digits (and here I think is where the error is) secret is a pre-assigned value

Once the signature is built it needs to be used via curl in a POST call, but Tuya keeps refusing the signature with the following error:

{"code":1004,"msg":"sign invalid","success":false,"t":1664314067553}

Now, I think that the issue is the timing. In order for my script to generate the signature few milliseconds are required and when the value of t gets passed to curl it won't match with the execution of curl (of course). Here's my code:

t=($(($(date +%s%N)/1000000))); sign1=$(echo -n "yyr8hxxxxxxxxd4mji$t" | openssl dgst -sha256 -hmac "cc75fd7xxxxxxxxx63d032b" | awk '{print$2}') && sign2=$(echo ${sign1^^}) ; curl --request POST "https://openapi.tuyaeu.com/v1.0/iot-03/devices/717715xxxxxxx520/commands" --header "sign_method: HMAC-SHA256" --header "client_id: yyr8hxxxxxxxxd4mji" --header "t: t" --header "mode: cors" --header "sign: $sign2" --header "access_token: cc75fd7xxxxxxxxx63d032b" --data "{"commands":[{"code":"switch_1","value":true}]}"

I've of course already tried to use && to execute all commands together but there has been no change. Does someone have any idea?

Solution

  • Your sign is invalid.

    Declare your variables:

    ClientID="replace_with_you_client_Id yyr8hxxxxxxxxd4mji"
ClientSecret="replace_with_you_client_secret cc75fd7xxxxxxxxx63d032b"
Device="replace_with_your_device 717715xxxxxxx520"

    First you have to get an access_token:

    AccessToken=$(t=$(date +%s%N |sed "s/......$//g"); curl -sSLkX GET "https://openapi.tuyaeu.com/v1.0/token?grant_type=1" -H "sign_method: HMAC-SHA256" -H "client_id: $ClientID" -H "t: $t" -H "mode: cors" -H "Content-Type: application/json" -H "sign: $(echo -en "${ClientID}${t}GET\ne3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855\n\n/v1.0/token?grant_type=1" | openssl dgst -sha256 -hmac "$ClientSecret"  | tr '[:lower:]' '[:upper:]' |sed "s/.* //g")" -H "access_token: " | sed "s/.*\"access_token\":\"//g"  |sed "s/\".*//g")`

    Then you need to calculate the good "sign". You need you ClientId, the timestamp, the access_token, the method, the encoded_body, the url:

    TimeStamp=$(date +%s%N |sed "s/......$//g")
METHOD='POST'
BODY='{"commands":[{"code":"switch_1","value":true}]}'
encodedBody=$(echo -n "$BODY" | openssl dgst -sha256 | sed "s/.*[ ]//g")
URL="/v1.0/iot-03/devices/$Device/commands"

    Calculate sign:

    SIGN=$(echo -n "$ClientID${AccessToken}${TimeStamp}${METHOD}
$encodedBody

$URL" | openssl dgst -sha256 -hmac "$ClientSecret"  | tr '[:lower:]' '[:upper:]' |sed "s/.* //g")`

    Or in one line:

    SIGN=$(echo -en "$ClientID${AccessToken}${TimeStamp}${METHOD}\n$encodedBody\n\n$URL" | openssl dgst -sha256 -hmac "$ClientSecret"  | tr '[:lower:]' '[:upper:]' |sed "s/.* //g")

    Then send the request:

    curl -sSLkX $METHOD "https://openapi.tuyaeu.com$URL" -H "sign_method: HMAC-SHA256" -H "client_id: $ClientID" -H "t: $TimeStamp" -H "mode: cors" -H "Content-Type: application/json" -H "sign: $SIGN" -H "access_token: $AccessToken" -d "$BODY"