* doc: clarify abigen alias flag usage

update the `abigen --alias` flag help info, give an example to make it more clear

related issue: https://github.com/ethereum/go-ethereum/issues/21846



* Update cmd/abigen/main.go

Co-authored-by: ligi <ligi@ligi.de>

Co-authored-by: Martin Holst Swende <martin@swende.se>
Co-authored-by: ligi <ligi@ligi.de>

Fixes the template used when generating code, which in some scenarios would lead to panic instead of returning an error.

This PR implements unclean shutdown marker. Every time geth boots, it adds a timestamp to a list of timestamps in the database. This list is capped at 10. At a clean shutdown, the timestamp is removed again. 
Thus, when geth exits unclean, the marker remains, and at boot up we show the most recent unclean shutdowns to the user, which makes it easier to diagnose root-causes to certain problems. 

Co-authored-by: Nagy Salem <me@muhnagy.com>

This PR adds re-written difficulty calculators, which are based on uint256. It also adds a fuzzer + oss-fuzz integration for the new fuzzer. It does differential fuzzing between the new and old calculators.

Note: this PR does not actually enable the new calculators.

* core: separate the local notion from the pricedHeap

* core: add benchmarks

* core: improve tests

* core: address comments

* core: degrade the panic to error message

* core: fix typo

* core: address comments

* core: address comment

* core: use PEAK instead of POP

* core: address comments

This PR adds support for using Twitter API to query the tweet and author details. There are two reasons behind this change:

- Twitter will be deprecating the legacy website on 15th December. The current method is expected to stop working then.
- More importantly, the current system uses Twitter handle for spam protection but the Twitter handle can be changed via automated calls. This allows bots to use the same tweet to withdraw funds infinite times as long as they keep changing their handle between every request. The Rinkeby as well as the Goerli faucet are being actively drained via this method. This PR changes the spam protection to be based on Twitter IDs instead of usernames. A user can not change their Twitter ID.

In miner/worker.go, there are two goroutine using channel w.newWorkCh: newWorkerLoop() sends to this channel, and mainLoop() receives from this channel. Only the receive operation is in a select.

However, w.exitCh may be closed by another goroutine. This is fine for the receive since receive is in select, but if the send operation is blocking, then it will block forever. This commit puts the send in a select, so it won't block even if w.exitCh is closed.

Similarly, there are two goroutines using channel errc: the parent that runs the test receives from it, and the child created at line 573 sends to it. If the parent goroutine exits too early by calling t.Fatalf() at line 614, then the child goroutine will be blocked at line 574 forever. This commit adds 1 buffer to errc. Now send will not block, and receive is not influenced because receive still needs to wait for the send.

The previous fix #21960 converted the float to an intermediate signed int, before attempting the uint conversion. Although this works, this doesn't guarantee that other architectures will work the same.

* les: introduce forkID

* les: address comment

This commit fixes a flaw in two testcases, and brings down the exec-time from ~40s to ~8s for trie/TestIncompleteSync.

The checkConsistency was performed over and over again on the complete set of nodes, not just the recently added, turning it into a quadratic runtime.

* les, light: remove untrusted header retrieval in ODR

* les: polish

* light: check the hash equality in odr

The database panicked for invalid IPs. This is usually no problem
because all code paths leading to node DB access verify the IP, but it's
dangerous because improper validation can turn this panic into a DoS
vulnerability. The quick fix here is to just turn database accesses
using invalid IP into a noop. This isn't great, but I'm planning to
remove the node DB for discv5 long-term, so it should be fine to have
this quick fix for half a year.

Fixes #21849

This fixes some issues in crypto/signify and makes release signing work.

The archive signing step in ci.go used getenvBase64, which decodes the key data.
This is incorrect here because crypto/signify already base64-decodes the key.

* core: add test for headerchain inserts

* core, light: write headerchains in batches

* core: change to one callback per batch of inserted headers + review concerns

* core: error-check on batch write

* core: unexport writeHeaders

* core: remove callback parameter in InsertHeaderChain

The semantics of InsertHeaderChain are now much simpler: it is now an
all-or-nothing operation. The new WriteStatus return value allows
callers to check for the canonicality of the insertion. This change
simplifies use of HeaderChain in package les, where the callback was
previously used to post chain events.

* core: skip some hashing when writing headers

* core: less hashing in header validation

* core: fix headerchain flaw regarding blacklisted hashes

Co-authored-by: Felix Lange <fjl@twurst.com>

Both Hash and Address have a String method, which returns the value as
hex with 0x prefix. They also had a Format method which tried to print
the value using printf of []byte. The way Format worked was at odds with
String though, leading to a situation where fmt.Sprintf("%v", hash)
returned the decimal notation and hash.String() returned a hex string.

This commit makes it consistent again. Both types now support the %v,
%s, %q format verbs for 0x-prefixed hex output. %x, %X creates
unprefixed hex output. %d is also supported and returns the decimal
notation "[1 2 3...]".

For Address, the case of hex characters in %v, %s, %q output is
determined using the EIP-55 checksum. Using %x, %X with Address
disables checksumming.

Co-authored-by: Felix Lange <fjl@twurst.com>

This commit enables users to specify which signer they want to use while creating their transactOpts.
Previously all contract interactions used the homestead signer. Now a user can specify whether they
want to sign with homestead or EIP155 and specify the chainID which adds another layer of security.

Closes #16484

Go won't vendor C files if there are no Go files present in the directory.
Workaround is to add dummy Go files.

Fixes: #20232

* les: revert arm float bug workaround to check go 1.15

* add traces to reproduce outside travis

* simpler workaround

* cmd/geth: implement vulnerability check

* cmd/geth: use minisign to verify vulnerability feed

* cmd/geth: add the test too

* cmd/geth: more minisig/signify testing

* cmd/geth: support multiple pubfiles for signing

* cmd/geth: add @holiman minisig pubkey

* cmd/geth: polishes on vulnerability check

* cmd/geth: fix ineffassign linter nit

* cmd/geth: add CVE to version check struct

* cmd/geth/testdata: add missing testfile

* cmd/geth: add more keys to versionchecker

* cmd/geth: support file:// URLs in version check

* cmd/geth: improve key ID printing when signature check fails

Co-authored-by: Felix Lange <fjl@twurst.com>

A lot of times when we hit 'core' errors, example: invalid tx, the information provided is
insufficient. We miss several pieces of information: what account has nonce too high,
and what transaction in that block was offending?

This PR adds that information, using the new type of wrapped errors.
It also adds a testcase which (partly) verifies the output from the errors.

The first commit changes all usage of direct equality-checks on core errors, into
using errors.Is. The second commit adds contextual information. This wraps most
of the core errors with more information, and also wraps it one more time in
stateprocessor, to further provide tx index and tx hash, if such a tx is encoutered in
a block. The third commit uses the chainmaker to try to generate chains with such
errors in them, thus triggering the errors and checking that the generated string meets
expectations.

This line is duplicated, though it doesn't cause any issues. 

This updates the snappy library depency to include a fix for
a Go 1.16 incompatibility issue. 

* eth: fix error in tracing if reexec is set

* eth: change pointer embedding to value-embedding

This PR fixes a deadlock reported here: #21925

The cause is that many operations may be pending, but if the close happens, only one of them gets awoken and exits, the others remain waiting for a signal that never comes.

Co-authored-by: Pascal Dierich <pascal@pascaldierich.com>

* signer/core/api: fix derivation of ledger live accounts

For ledger hardware wallets, change account iteration as follows:

- ledger legacy: m/44'/60'/0'/X; for 0<=X<5
- ledger live: m/44'/60'/0'/0/X; for 0<=X<5

- ledger legacy: m/44'/60'/0'/X; for 0<=X<10
- ledger live: m/44'/60'/X'/0/0; for 0<=X<10

Non-ledger derivation is unchanged and remains as:
- non-ledger: m/44'/60'/0'/0/X; for 0<=X<10

* signer/core/api: derive ten default paths for all hardware wallets, plus ten legacy and ten live paths for ledger wallets

* signer/core/api: as .../0'/0/0 already included by default paths, do not include it again with ledger live paths

* accounts, signer: implement path iterators for hd wallets

Co-authored-by: Martin Holst Swende <martin@swende.se>

* internal/build: implement signify's signing func
* Add signify to the ci utility
* fix output file format
* Add unit test for signify
* holiman's + travis' feedback
* internal/build: verify signify's output
* crypto: move signify to common dir
* use go-minisign to verify binaries
* more holiman feedback
* crypto, ci: support minisign output
* only accept one-line trusted comments
* configurable untrusted comments
* code cleanup in tests
* revert to use ed25519 from the stdlib
* bug: fix for empty untrusted comments
* write timestamp as comment if trusted comment isn't present
* rename line checker to commentHasManyLines
* crypto: added signify fuzzer (#6)
* crypto: added signify fuzzer
* stuff
* crypto: updated signify fuzzer to fuzz comments
* crypto: repro signify crashes
* rebased fuzzer on build-signify branch
* hide fuzzer behind gofuzz build flag
* extract key data inside a single function
* don't treat \r as a newline
* travis: fix signing command line
* do not use an external binary in tests
* crypto: move signify to crypto/signify
* travis: fix formatting issue
* ci: fix linter build after package move

Co-authored-by: Marius van der Wijden <m.vanderwijden@live.de>

This fixes a deadlock that could occur when a response packet arrived
after a call had already received enough responses and was about to
signal completion to the dispatch loop.

Co-authored-by: Felix Lange <fjl@twurst.com>

* Make sure to return 400 when errors are present in the response

* graphql: use less memory in chainconfig for tests

Co-authored-by: Martin Holst Swende <martin@swende.se>