When signing a transaction will result in the sighash single bug being
exploitable we should return the 'one array' (equivalent to 1 as a
uint256) as the signature hash.
Add a unit test to verify we return uint256 1 value when use of
SIGHASH_SINGLE is invalid.
When signing a transaction will result in the sighash single bug being
exploitable we should return the 1 array (equivalent to 1 as a uint256)
as the signature hash.
Currently we are using the correct array value but are re-hashing it,
instead we should directly return it.
f4886afa66 Add full stops to docs (Tobin Harding)
f01f047b21 Remove unnecessary newlines (Tobin Harding)
8a1cc2ca77 Improve docs on ClassifyContext (Tobin Harding)
Pull request description:
Do some clean ups to the `blockdata::opcodes` module. Patch 3 is big but it should be quick to review because I made all the boring 'add full stops' changes in a single commit.
ACKs for top commit:
Kixunil:
ACK f4886afa66
apoelstra:
ACK f4886afa66
dr-orlovsky:
ACK f4886afa66
Tree-SHA512: b30f36bd06a028b6bbc24a64849c0788a9223760907bdcb3765af1742a228f630cc7666ed66fa2afd8fb6c96e3cf416e9bd9d2a3b6c72c6e47a16399a856fca1
146d5e83d1 Improve docs for blockdata::block (Tobin Harding)
f03092c380 Fix erroneous function rustdoc (Tobin Harding)
5464848f45 Refactor check_witness_commitment (Tobin Harding)
Pull request description:
Do some clean ups to the `blockdata::block` module.
- Patch 1: Change predicate names (API breaking, could be seen as unnecessarily changing the API), can remove if NACK'd
- Patch 2: Refactor to assist code clarity
- Patch 3 and 4: are docs improvements, shouldn't be too controversial
ACKs for top commit:
apoelstra:
ACK 146d5e83d1
dr-orlovsky:
ACK 146d5e83d1
Tree-SHA512: 65cc414857c4569a389638b53eb99ed629bf67ae1d8ebdc9023e5974bb26902d4de41ec311bef3b5c895229d7d0df78d469a84c1e94fc0b7be7435338f0d510a
e503f14331 Improve docs: blockdata::transaction (Tobin Harding)
f02b3a8472 Add code comment for emtpy input (Tobin Harding)
6a0ec1ac47 Remove redundant _eq (Tobin Harding)
3bcc146a44 Improve docs: encode_signing_data_to/signature_hash (Tobin Harding)
Pull request description:
Do some cleanups to the docs in `blockdata::transaction`. Patch 1 needs the most careful review please. The rest should not be too controversial.
ACKs for top commit:
apoelstra:
ACK e503f14331
dr-orlovsky:
ACK e503f14331
Tree-SHA512: 3953226e1b7f0db0371b1902888407a48531688bf8ed08539a0090f369b491b130d70b2fae859878ef178a397cefe0ee2a15f3358afc990a2776194cc2b3882b
4dcbef6ddd Improve docs: script module (Tobin Harding)
Pull request description:
Improve the docs in the `blockdata::script` module by doing:
- Use full sentences (use capitals and full stops)
- Improve grammar/wording if necessary
- Remove incorrect/unneeded comments
- Fix layout of rustdoc i.e., use brief and description sections
- Use 100 line character width if it makes the comment look better
- Use third person instead of imperative tense
## Note to reviewers
Sorry to be a bore and request review on all these docs fixes, this one is all in a single patch which makes it a bit harder to review. It is very similar in content to all the others that are open right now so I'm going to be a bit rude and leave it like this. Please say if this is even slightly putting too much demand on you review time.
ACKs for top commit:
apoelstra:
ACK 4dcbef6ddd
dr-orlovsky:
ACK 4dcbef6ddd
Tree-SHA512: 49fa1d88c4b97decbc563747ba166fe95698da6a634801ccf5f99fd67a4a907067dbf0a4d64e7773d5d5b04aef404167b6cc911382363247d15a61cef5d8965c
Improve the docs in the `blockdata::script` module by doing:
- Use full sentences (use capitals and full stops)
- Improve grammar/wording if necessary
- Remove incorrect/unneeded comments
- Fix layout of rustdoc i.e., use brief and description sections
- Use 100 line character width if it makes the comment look better
- Use third person instead of imperative tense
Improve the rustdocs for the `blockdata::transaction` module:
- Use full sentences (capitalisation and full stop)
- Use third person tense instead of imperative
- Improve wording/grammar
- Use backticks in links
- Use 100 character column width if it improves readability
Nothing too controversial here :)
The line of code `let mut have_witness = self.input.is_empty();` is
puzzling if one does not know _why_ we serialize in BIP141 style when
there are no inputs.
Add a code comment to save devs spending time trying to work out _why_
this is correct.
The two methods `encode_signing_data_to` and `signature_hash` use the
same docs (one is a public helper for the other). The docs have gotten a
bit stale (refer to deprecated types).
Instead of duplicating all the text, add a statement pointing readers
from the docs of `signature_hash` to the docs on
`encode_signing_data_to`.
Improve the rustdocs for the `blockdata::block` module:
- Use full sentences (capitalisation and full stop)
- Use third person tense instead of imperative
- Improve wording if needed
Currently function contains nested `if` clauses that arguably obfuscate
the code. We can make the code easier to read by pulling out the error
paths and returning them higher up in the function.
Refactor only, no logic changes.
Simplify `read_scriptbool` by doing:
- Use `split_last` to get at the last element
- Mask the last byte against ^0x80 instead of using two equality
statements
This commit tries to achieve separation of signature- and key-related types, previously mixed in a single ECDSA module.
Rationale: bitcoin key types are not specific for signature algorithm.
This is achieved through
- Remove key mod with its content moved to ecdsa mod
- Re-export keys under key module in util mod - to make git generate diff for the rename of ecdsa mod in the next commit correctly.
7405836411 Fix warning about deprecated method use (Dr Maxim Orlovsky)
f39b1300fa CI: do not fail fast (Dr Maxim Orlovsky)
f77c57195a Making Script method new_* names more consistent (Dr Maxim Orlovsky)
91b68a468d Taproot-related methods for Script type (Dr Maxim Orlovsky)
599c5f9488 Generalizing taproot key tweaking for KeyPairs (Dr Maxim Orlovsky)
Pull request description:
* Adds taproot-related methods to `Script`
* Fixes API for existing taproot methods
* Generalizes `TapTweak` trait to work with both public keys and key pairs
~~UPD: PR is pending https://github.com/rust-bitcoin/rust-secp256k1/pull/342~~
ACKs for top commit:
sanket1729:
ACK 7405836411
apoelstra:
ACK 7405836411
Tree-SHA512: 4a76dfffa1452baadc15e19812831ef9d2e66794c090a8fc123388d7119b2c8a1f0420ce723ad22e01683c8198711fe62e0cdf00c9ad2d2974606383baaf1cb0
I think it is more natural to write Wintess::new() followed by Witness::push()
then Witness::default(). In any case, there is no harm in having additional constructors.
Fourth step in implementation of Schnorr key support after #588.
While PSBT BIP174 does not specify whether uncompressed keys are supported in BIP32-related fields, from BIP32 it follows that it is impossible to use uncompressed keys within the extended keys. This PR fixes this situation and is a companion to BIP174 PR clarifying key serialization: https://github.com/bitcoin/bips/pull/1100
247a14f4c3 Use test big block for bench_stream_reader instead of making one (Riccardo Casatta)
b92dfbb63f exclude test_data when publishing the crate (Riccardo Casatta)
f5a9681a2a include a big block in test_data, use it for ser/de benchmark (Riccardo Casatta)
09dada55d6 Move bip158 test vectors to test_data (Riccardo Casatta)
06d1a820c3 Remove testnet block hex from tests, use test_data with include_bytes! (Riccardo Casatta)
Pull request description:
In the first two commits I moved some data from source files to the newly introduced `test_data` dir, including it with `include_[str|bytes]!` macro.
The second-to-last commit introduces a big block in test_data which is very handy in ser/de benchmark (I used it for #672) because with smaller blocks you may not notice performance improvements.
Since I don't want to pollute the package the last commit excludes the `test_data` dir from the published package. I think it's fine to do it because dependent packages don't run dependencies tests.
ACKs for top commit:
apoelstra:
ACK 247a14f4c3
Kixunil:
tACK 247a14f4c3
Tree-SHA512: a2beb635b0a358737d0b57d3e7205b1ddf87652b9a8c889ce63e2867659a8eaf7e43a5b87a453345d56d953745913f40b58596f449e5fbc87340e0dd2aef0727
533120899e Put rustdocs above attributes (Tobin Harding)
Pull request description:
(Trivial / Very low priority PR)
Rust idiomatic style is to put the rustdoc _above_ any attributes on types, functions, etc.
Audit the codebase and move comments/attributes to the correct place. Add a trailing full stop at times to neaten things up a little extra.
Done after discussion [here](https://github.com/rust-bitcoin/rust-secp256k1/pull/353#discussion_r778393138)
ACKs for top commit:
Kixunil:
ACK 533120899e
RCasatta:
ACK 533120899e
Tree-SHA512: 7cd00dc46de813cbe3f96417bb4b13980064e10110b421224496c8b64bbe87b61b6c757cc621fde1d05754be6ecdc08acdb51fd8978e3f820d2d93f7104062d1
e860333bf3 Fix typos (Riccardo Casatta)
9189539715 Use BufReader internally in StreamReader to avoid performance regression on existing callers (Riccardo Casatta)
5dfb93df71 Deprecate StreamReader (Riccardo Casatta)
9ca6c75b18 Bench StreamReader (Riccardo Casatta)
Pull request description:
`StreamReader` performance is extremely poor in case the object decoded is "big enough" for example a full Block.
In the common case, the buffer is 64k, so to successfully parse a 1MB block 16 decode attempts are made.
Even if a user increases the buffer size, `read` is not going to necessarily fill the buffer, as stated in the doc https://doc.rust-lang.org/stable/std/io/trait.Read.html#tymethod.read. In my tests, the reads are 64kB even with a 1MB buffer.
I think this is the root issue of the performance issue found in electrs in https://github.com/romanz/electrs/issues/547 and they now have decided to decode the TCP stream with their own code in cd0531b8b7 and 05e0221b8e.
Using directly `consensus_encode` seems to make more sense (taking care of using `BufRead` if necessary) so the `StreamReader` is deprecated
ACKs for top commit:
Kixunil:
ACK e860333bf3
apoelstra:
ACK e860333bf3
Tree-SHA512: a15a14f3f087be36271da5008d8dfb63866c9ddeb5ceb0e328b4a6d870131132a8b05103f7a3fed231f5bca099865efd07856b4766834d56ce2384b1bcdb889b
Rust idiomatic style is to put the rustdoc _above_ any attributes on
types, functions, etc.
Audit the codebase and move comments/attributes to the correct place.
Add a trailing full stop at times to neaten things up a little extra.
106acdc3ac Add fuzzing for Witness struct (Riccardo Casatta)
2fd0125bfa Introduce Witness struct mainly to improve ser/de performance while keeping most usability. (Riccardo Casatta)
Pull request description:
At the moment the Witness struct is `Vec<Vec<u8>>`, the vec inside a vec cause a lot of allocations, specifically:
- empty witness -> 1 allocation, while an empty vec doesn't allocate, the outer vec is not empty
- witness with n elements -> n+1 allocations
The proposed Witness struct contains the serialized format of the witness. This reduces the allocations to:
- empty witness -> 0 allocations
- witness with n elements -> 1 allocation for most common cases (you don't know how many bytes is long the entire witness beforehand, thus you need to estimate a good value, not too big to avoid wasting space and not too low to avoid vector reallocation, I used 128 since it covers about 80% of cases on mainnet)
The inconvenience is having slightly less comfortable access to the witness, but the iterator is efficient (no allocations) and you can always collect the iteration to have a Vec of slices. If you collect the iteration you end up doing allocation anyway, but the rationale is that it is an operation you need to do rarely while ser/de is done much more often.
I had to add a bigger block to better see the improvement (ae860247e191e2136d7c87382f78c96e0908d700), these are the results of the benches on my machine:
```
RCasatta/master_with_block
test blockdata::block::benches::bench_block_deserialize ... bench: 5,496,821 ns/iter (+/- 298,859)
test blockdata::block::benches::bench_block_serialize ... bench: 437,389 ns/iter (+/- 31,576)
test blockdata::block::benches::bench_block_serialize_logic ... bench: 108,759 ns/iter (+/- 5,807)
test blockdata::transaction::benches::bench_transaction_deserialize ... bench: 670 ns/iter (+/- 49)
test blockdata::transaction::benches::bench_transaction_get_size ... bench: 7 ns/iter (+/- 0)
test blockdata::transaction::benches::bench_transaction_serialize ... bench: 51 ns/iter (+/- 5)
test blockdata::transaction::benches::bench_transaction_serialize_logic ... bench: 13 ns/iter (+/- 0)
branch witness_with_block (this one)
test blockdata::block::benches::bench_block_deserialize ... bench: 4,302,788 ns/iter (+/- 424,806)
test blockdata::block::benches::bench_block_serialize ... bench: 366,493 ns/iter (+/- 42,216)
test blockdata::block::benches::bench_block_serialize_logic ... bench: 84,646 ns/iter (+/- 7,366)
test blockdata::transaction::benches::bench_transaction_deserialize ... bench: 648 ns/iter (+/- 77)
test blockdata::transaction::benches::bench_transaction_get_size ... bench: 7 ns/iter (+/- 0)
test blockdata::transaction::benches::bench_transaction_serialize ... bench: 50 ns/iter (+/- 5)
test blockdata::transaction::benches::bench_transaction_serialize_logic ... bench: 14 ns/iter (+/- 0)
```
With an increased performance to deserialize a block of about 21% and to serialize a block of about 16% (seems even higher than expected, need to do more tests to confirm, I'll appreciate tests results from reviewers)
ACKs for top commit:
apoelstra:
ACK 106acdc3ac
sanket1729:
ACK 106acdc3ac
dr-orlovsky:
utACK 106acdc3ac
Tree-SHA512: e4f23bdd55075c7ea788bc55846fd9e30f9cb76d5847cb259bddbf72523857715b0d4dbac505be3dfb9d4b1bcae289384ab39885b4887e188f8f1c06caf4049a
Witness struct is in place of the Vec<Vec<u8>> we have before this commit.
from_vec() and to_vec() methods are provided to switch between this type and Vec<Vec<u8>>
Moreover, implementation of Default, Iterator and others allows to have similar behaviour but
using a single Vec prevent many allocations during deserialization which in turns results in
better performance, even 20% better perfomance on recent block.
last() and second_to_last() allows to access respective element without going through costly Vec
transformation
826fed53f2 transactions: add a note about `get_vsize` and standardness rules (Antoine Poinsot)
Pull request description:
If they ever hit a discrepancy they must really be doing something dodgy but hey :)
ACKs for top commit:
dr-orlovsky:
ACK 826fed53f2
Tree-SHA512: c618a80b047797625a233939d2c1146e8b4ce44215648841813f78178577afc844f5e561e4e60b4084e315735894ecb354af8d81f4702f5354e5d5cd05b52ac4
This is the initial step towards using and maybe enforcing clippy.
It does not fix all lints as some are not applicable. They may be
explicitly ignored later.
b454cf8e15 Return None from merkle_root functions (Tobin Harding)
7a8b017ea3 Use correct spelling of merkle (Tobin Harding)
Pull request description:
~Do two minor refactorings to the `bitcoin_merkle_root[_inline] functions.~
This PR has grown, is no longer a refactoring because the two functions have been changed to return an `Option`.
First patch is cleanup. Here is the commit message for the second patch
```
The merkle_root of an empty tree is undefined, this is the only error
case we have for the two `bitcoin_merkle_root*` functions. We can fully
describe this error case by returning an `Option` if args are found to
be empty.
While we are at it, refactor out a recursive helper function to make
reading the code between the two functions easier.
```
ACKs for top commit:
Kixunil:
ACK b454cf8e15
dr-orlovsky:
ACK b454cf8e15
Tree-SHA512: 961714a8b0eb0dad493a1548317d875d64ca22d2d584c905c502369b5f6e5a9f8be1edd7345136b44964dc0bde7a4c43bfaff4287d1dbf7fd736da79818074e3
The merkle_root of an empty tree is undefined, this is the only error
case we have for the two `bitcoin_merkle_root*` functions. We can fully
describe this error case by returning an `Option` if args are found to
be empty. We can do the same for the wrapper functions in `block`
module.
While we are at it, refactor out a recursive helper function to make
reading the code between the two functions easier.
`Instructions` guarantee to return `None` from empty iterator so we
should signal this in type system so that the code can be optimized
better. This also adds a test to make sure this property holds.
Calls to `unwrap` outside of tests are typically unfavourable.
Sink writers do not error. We can use `expect` with a descriptive
message string to indicate this.
Calls to `unwrap` outside of tests are typically unfavourable.
Hash engines do not error when calling `consensus_encode`. Instead of
the current usage of `unwrap` we can use `expect` with a descriptive
string as is done in other parts of the codebase.
Docs can always do with a bit of love.
Clean up the module level (`//!`) rustdocs for all public modules.
I claim uniform is better than any specific method/style. I tried to fit
in with what ever was either most sane of most prevalent, therefore
attaining uniformity without unnecessary code churn (one exception being
the changes to headings described below).
Notes:
* Headings - use heading as a regular sentence for all modules e.g.,
```
//! Bitcoin network messages.
```
as opposed to
```
//! # Bitcoin Network Messages
```
It was not clear which style to use so I picked a 'random' mature
project and copied their style.
* Added 'This module' in _most_ places as the start of the module
description, however I was not religious about this one.
* Fixed line length if necessary since most of our code seems to follow
short (80 char) line lengths for comments anyways.
* Added periods and fixed obvious (and sometimes not so obvious)
grammatically errors.
* Added a trailing `//!` to every block since this was almost universal
already. I don't really like this one but I'm guessing it is Andrew's
preferred style since its on the copyright notices as well.
This refactors `Script::bytes_to_asm_fmt`` function to use an iterator
instead of index. Such change makes it easier to reason about overflows
or out-of-bounds accesses. As a result this also fixes three unlikely
overflows and happens to improve formatting to not output space at the
beginning in some weird cases.
To improve robustness even better it also moves `read_uint`
implementation to internal function which returns a more specific error
type which can be exhaustively matched on to guarantee correct error
handling. Probably because of lack of this the code was previously
checking the same condition twice, the second time being unreachable and
attempting to behave differently than the first one.
Finally this uses macro to deduplicate code which differs only in single
number, ensuring the code stays in sync across all branches.
76cf74fa9b Added test for the overflow bug and few others (Martin Habovstiak)
a0e1d2e706 Check for overflow in Script::bytes_to_asm_fmt() (Martin Habovstiak)
Pull request description:
This adds an overflow check in `Script::bytes_to_asm_fmt()` motivated by
`electrs` issue. While it was not tested yet, I'm very confident that
overflow is the cause of panic there and even if not it can cause panic
becuase the public function takes unvalidated byte array and reads
`data_len` from it.
The `electrs` issue: https://github.com/romanz/electrs/issues/490
~~Strangely, this breaks a test case and I can't see why. I'm publishing in case someone wants to help.~~
Edit: One damn character. :D Should be OK now.
ACKs for top commit:
apoelstra:
ACK 76cf74fa9b
Tree-SHA512: 4ffeca442a71b10c132f055f056128ae64e66cbdc1891662c3a4e743b82fa5d27075a44513e844be37888b33068eef3bbf6bcced5def70c17c9c5bd5b9d870cc
This adds a test case for script formatting which caused overflow in the
past and a few others from the same "interesting" transaction. Note that
to trigger the bug one has to run the test on 32 bit architecture.
This adds an overflow check in `Script::bytes_to_asm_fmt()` motivated by
`electrs` issue. While it was not tested yet, I'm very confident that
overflow is the cause of panic there and even if not it can cause panic
becuase the public function takes unvalidated byte array and reads
`data_len` from it.
The `electrs` issue: https://github.com/romanz/electrs/issues/490
c704ee7ffe [docs-only] Use backtick in addition to square parentheses for types references, clarify legacy, non_exhaustive comment, remove std:: (Riccardo Casatta)
f223be618f Rename access_witness to witness_mut and return Option (Riccardo Casatta)
c9bc0b928a [fmt-only] autoformatting with `rustfmt src/util/sighash.rs` (Riccardo Casatta)
07774917c2 Use get_or_insert_with in segwit_cache (Martin Habovstiak)
497dbfb7c3 Use get_or_insert_with in common_cache() (Martin Habovstiak)
ca80a5a030 Use get_or_insert_with in taproot_cache (Martin Habovstiak)
6e06a32ccc Wrap ErrorKind in Io enum variant, fix doc comment for the IO variant (Riccardo Casatta)
1a2b54ff23 introduce constant KEY_VERSION_0 (Riccardo Casatta)
417cfe31e3 Derive common traits for structs and enum, make internal struct not pub (Riccardo Casatta)
55ce3dd6ae Fix validation error if SINGLE with missing corresponding output, remove check_index and check with get().ok_or(), more details in errors (Riccardo Casatta)
2b3b22f559 impl Encodable for Annex to avoid allocation (Riccardo Casatta)
1a7afed068 Add Reserved variant to SigHashType for future use (ie SIGHASH_ANYPREVOUT) (Riccardo Casatta)
53d0e176d3 Deprecate bip143::SigHashCache in favor of sighash::SigHashCache (Riccardo Casatta)
15e3caf62d [test] Test also sighash legacy API with legacy tests (Riccardo Casatta)
24acfe3672 Implement Bip341 signature hash, create unified SigHashCache for taproot, segwit and legacy inputs (Riccardo Casatta)
683b9c14ff add [En|De]codable trait for sha256::Hash (Riccardo Casatta)
Pull request description:
Adds https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki message signature algorithm
The base is taken from `bip143::SigHashCache`, some code results duplicated but I think it's more clear to keep things separated
Would mark some bullet point on https://github.com/rust-bitcoin/rust-bitcoin/issues/503
Test vectors are taken by running d1e4c56309/test/functional/feature_taproot.py with a modified `TaprootSignatureHash` function to print intermediate values that I cannot found in the bip341 [test vector json](https://raw.githubusercontent.com/bitcoin-core/qa-assets/main/unit_test_data/script_assets_test.json)
UPDATE: Latest version includes the suggestion from @sanket1729 to create a unified tool for signature message hash for legacy, segwit, and taproot inputs. In particular, makes sense for mixed segwit v0 and taproot v1 inputs because cached values could be shared
ACKs for top commit:
sanket1729:
ACK c704ee7ffe. Reviewed the diff from a37de1ade475e0c31c932121abaa7aec701b9987 which I previously ACKed
dr-orlovsky:
utACK c704ee7ffe by diffing it to 6e06a32ccc having my ACK before.
apoelstra:
ACK c704ee7ffe
Tree-SHA512: 35530995fe9d078acd0178cfca654ca980109f4502c91d578c1a0d5c6cafacab7db1ffd6216288eac99f6a763776cbc0298cfbdff00b5a83e98ec4b15aa764e8
This documents cargo features in two ways: explictly in text and in code
using `#[doc(cfg(...))]` attribute where possible. Notably, this is
impossible for `serde` derives. The attribute is contitional and only
activated for docs.rs or explicit local builds.
This change also adds `package.metadata.docs.rs` field to `Cargo.toml`
which instructs docs.rs to build with relevant features and with
`docsrs` config activated enabling `#[doc(cfg(...))] attributes.
I also took the opportunity to fix a few missing spaces in nearby code.
Instead of using magic numbers we can define constants for the address
prefix bytes. This makes it easier for future readers of the code to see
what these values are if they don't know them and/or see that they are
correct if they do know them.
Based on the original work by Justin Moon.
*MSRV unchanged from 1.29.0.*
When `std` is off, `no-std` must be on, and we use the [`alloc`](https://doc.rust-lang.org/alloc/) and core2 crates. The `alloc` crate requires the user define a global allocator.
* Import from `core` and `alloc` instead of `std`
* `alloc` only used if `no-std` is on
* Create `std` feature
* Create `no-std` feature which adds a core2 dependency to polyfill `std::io` features. This is an experimental feature and should be
used with caution.
* CI runs tests `no-std`
* MSRV for `no-std` is 1.51 or so
This introduces some constants defined by Bitcoin Core which as a
consequence define some network rules in a new 'policy' module.
Only some were picked, which are very unlikely to change. Nonetheless a
Warning has been put in the module documentation.
Script-level constants are left into rust-miniscript where they are
already defined (src/miniscript/limits.rs).
Tobin Harding
Dr Maxim Orlovsky
Casey Rodarmor
sanket1729
Andrew Poelstra
Nils Loewen
Riccardo Casatta
Martin Habovstiak
Antoine Poinsot
Vikas S Shetty
Devrandom
Vis Virial
Sebastian
Sebastian Geisler