Suppose I sent a signed transaction using the web3.js library. But, I might be using some third party API like an Infura node or others. So there are chances of attacks and data manipulation. So, is there any way to verify if the all transaction data entered in the blockchain is same as the one entered by me or if it has been manipulated by someone?
You can look at the receipt of the transaction to verify the data yourself. The web3.js library's
sendSignedTransaction will return a receipt that you can check to verify the data.
Edit based on goodvibration's comments
My original answer was as follows:
A signed transaction cannot be altered, as the data within the transaction has already been signed. If any data is manipulated, then the signature would be invalid and the transaction would never be broadcasted.
However, this is not entirely true in the case where a user's private key is shared among other parties. Because of this, the original answer does not apply.