Add a special case for passing original calldata with symbolic length

Description

As described in #674, Mythril currently doesn’t support the delegatecall proxy pattern where the original calldata is passed through. This is because we don’t support calldata with a symbolic offset or length.

I suppose that we could add a special case for offset = 0 and length = calldatasize where we provide the original calldata to the callee.

[nbanmp]

We don’t need a special case for this, we could choose to handle it correctly with some modifications to Calldata.

If a Calldata can take another Calldata object as the starting_calldata, as well as the offest and length as keyword arguments, to grab a value from an index, the new calldata can return previousCalldata[index + offset] and the constraint ULT(index, length),

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

---

The funding of 2.5 ETH (285.9 USD @ $114.36/ETH) attached to this issue has been approved & issued to @nbanmp.

• Learn more on the Gitcoin Issue Details page
• Questions? Checkout Gitcoin Help or the Gitcoin Slack
• $34,566.30 more funded OSS Work available on the Gitcoin Issue Explorer