Re: [Bitcoin-development] OpenSSL 1.0.0p / 1.0.1k incompatible, causes blockchain rejection.
On Sat, Jan 10, 2015 at 12:18 PM, Ivan Jelincic wrote: > Is openssl1.0.1j unaffected? Yes. It concerns CVE-2014-8275. Which in https://www.openssl.org/news/openssl-1.0.1-notes.html is under: Major changes between OpenSSL 1.0.1j and OpenSSL 1.0.1k [8 Jan 2015] Wladimir -- New Year. New Location. New Benefits. New Data Center in Ashburn, VA. GigeNET is offering a free month of service with a new server in Ashburn. Choose from 2 high performing configs, both with 100TB of bandwidth. Higher redundancy.Lower latency.Increased capacity.Completely compliant. vanity: www.gigenet.com ___ Bitcoin-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] OpenSSL 1.0.0p / 1.0.1k incompatible, causes blockchain rejection.
Is openssl1.0.1j unaffected? On 01/10/2015 09:35 AM, Wladimir wrote: > On Sat, Jan 10, 2015 at 4:26 AM, Gregory Maxwell wrote: >> https://github.com/bitcoin/bitcoin/commit/488ed32f2ada1d1dd108fc245d025c4d5f252783 >> (versions of this will be backported to other stable branches soon) > For those that build from source, patches to cope with the new OpenSSL > versions are now available on stable branches 0.8, 0.9 and rc branch > 0.10: > > 0.8 branch (on top of 0.8.6) > > https://github.com/bitcoin/bitcoin/tree/0.8 > https://github.com/bitcoin/bitcoin/commits/0.8 > > To fetch, build, and test: > ``` > git clone -b 0.8 https://github.com/bitcoin/bitcoin.git bitcoin-0.8 > cd bitcoin-0.8/src > make -f makefile.unix > make -f makefile.unix check > ``` > > 0.9 branch (on top of 0.9.3+) > > https://github.com/bitcoin/bitcoin/tree/0.9 > https://github.com/bitcoin/bitcoin/commits/0.9 > > To fetch, build, and test: > ``` > git clone -b 0.9 https://github.com/bitcoin/bitcoin.git bitcoin-0.9 > cd bitcoin-0.9/src > ./autogen.sh > ./configure > make > make check > ``` > > 0.10 branch (on top of 0.10.0rc1+) > > https://github.com/bitcoin/bitcoin/tree/0.10 > https://github.com/bitcoin/bitcoin/commits/0.10 > > ``` > git clone -b 0.10 https://github.com/bitcoin/bitcoin.git bitcoin-0.10 > cd bitcoin-0.10/src > ./autogen.sh > ./configure > make > make check > ``` > > Wladimir > > -- > Dive into the World of Parallel Programming! The Go Parallel Website, > sponsored by Intel and developed in partnership with Slashdot Media, is your > hub for all things parallel software development, from weekly thought > leadership blogs to news, videos, case studies, tutorials and more. Take a > look and join the conversation now. http://goparallel.sourceforge.net > ___ > Bitcoin-development mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Bitcoin-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] OpenSSL 1.0.0p / 1.0.1k incompatible, causes blockchain rejection.
On Sat, Jan 10, 2015 at 4:26 AM, Gregory Maxwell wrote: > https://github.com/bitcoin/bitcoin/commit/488ed32f2ada1d1dd108fc245d025c4d5f252783 > (versions of this will be backported to other stable branches soon) For those that build from source, patches to cope with the new OpenSSL versions are now available on stable branches 0.8, 0.9 and rc branch 0.10: 0.8 branch (on top of 0.8.6) https://github.com/bitcoin/bitcoin/tree/0.8 https://github.com/bitcoin/bitcoin/commits/0.8 To fetch, build, and test: ``` git clone -b 0.8 https://github.com/bitcoin/bitcoin.git bitcoin-0.8 cd bitcoin-0.8/src make -f makefile.unix make -f makefile.unix check ``` 0.9 branch (on top of 0.9.3+) https://github.com/bitcoin/bitcoin/tree/0.9 https://github.com/bitcoin/bitcoin/commits/0.9 To fetch, build, and test: ``` git clone -b 0.9 https://github.com/bitcoin/bitcoin.git bitcoin-0.9 cd bitcoin-0.9/src ./autogen.sh ./configure make make check ``` 0.10 branch (on top of 0.10.0rc1+) https://github.com/bitcoin/bitcoin/tree/0.10 https://github.com/bitcoin/bitcoin/commits/0.10 ``` git clone -b 0.10 https://github.com/bitcoin/bitcoin.git bitcoin-0.10 cd bitcoin-0.10/src ./autogen.sh ./configure make make check ``` Wladimir -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Bitcoin-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] OpenSSL 1.0.0p / 1.0.1k incompatible, causes blockchain rejection.
On Sat, Jan 10, 2015 at 04:26:23AM +, Gregory Maxwell wrote: > The incompatibility is due to the OpenSSL update changing the > behavior of ECDSA validation to reject any signature which is > not encoded in a very rigid manner. This was a result of > OpenSSL's change for CVE-2014-8275 "Certificate fingerprints > can be modified". > > While for most applications it is generally acceptable to eagerly > reject some signatures, Bitcoin is a consensus system where all > participants must generally agree on the exact validity or > invalidity of the input data. In a sense, consistency is more > important than "correctness". As an aside, it's interesting to note that this issue is not entirely unique to miners. For example in micropayment channel protocols the receiver must validate signatures from the sender to ensure that they will be able to broadcast transactions containing those signatures in the near-future. If they accept a signature as valid that the majority of hashing power rejects as invalid the sender can simply wait until the micropayment channel timeout expires to recover 100% of their funds, ripping off the receiver. There's many other advanced Bitcoin protocols with similar vulnerabilities; I'd be interested to hear if anyone can come up with a similar vulnerability in a non-Bitcoin protocol, and wouldn't be that surprised if they did. While I have often cautioned people before to avoid using libsecp256k1 for verification on the grounds that consensus trumps correctness, the above incompatibility does strongly suggest that OpenSSL may not itself have very good consensus-critical design. Along with Maxwell and Wuille's recent findings¹ CVE-2014-3570 - strong evidence of the excellent testing the library has undergone - I personally am now of the opinion that migrating Bitcoin Core to libsecp256k1 in the near future is a good idea on the grounds that it provides us with a well-written, and well-understood library designed with consensus in mind that'll probably give us fewer consensus problems than our existing OpenSSL dependency. It'll also help advanced protocol implementations by giving them a clear dependency to use when they need consensus-critical signature evaluation. 1) https://www.reddit.com/r/Bitcoin/comments/2rrxq7/on_why_010s_release_notes_say_we_have_reason_to/ -- 'peter'[:-1]@petertodd.org 003b82d8644b56c846e7497118b04a6ec68d3e0a23d33323b82e signature.asc Description: Digital signature -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net___ Bitcoin-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bitcoin-development
[Bitcoin-development] OpenSSL 1.0.0p / 1.0.1k incompatible, causes blockchain rejection.
OpenSSL 1.0.0p / 1.0.1k was recently released and is being pushed out by various operating system maintainers. My review determined that this update is incompatible with the Bitcoin system and could lead to consensus forks. Bitcoin Core released binaries from Bitcoin.org are unaffected, as are any built with the gitian deterministic build system. If you are running third-party or self-compiled Bitcoin Core or an alternative implementation using OpenSSL you must not update OpenSSL or must run a Bitcoin software containing a workaround: https://github.com/bitcoin/bitcoin/commit/488ed32f2ada1d1dd108fc245d025c4d5f252783 (versions of this will be backported to other stable branches soon) The tests included with Bitcoin Core in the test_bitcoin utility already detect this condition and fail. (_Do not ignore or disable the tests in order to run or distribute software which fails_) The incompatibility is due to the OpenSSL update changing the behavior of ECDSA validation to reject any signature which is not encoded in a very rigid manner. This was a result of OpenSSL's change for CVE-2014-8275 "Certificate fingerprints can be modified". While for most applications it is generally acceptable to eagerly reject some signatures, Bitcoin is a consensus system where all participants must generally agree on the exact validity or invalidity of the input data. In a sense, consistency is more important than "correctness". As a result, an uncontrolled 'fix' can constitute a security vulnerability for the Bitcoin system. The Bitcoin Core developers have been aware of this class of risk for a long time and have taken measures to mitigate it generally; e.g., shipping static binaries, internalizing the Leveldb library... etc. It was somewhat surprising, however, to see this kind of change show up as a "low" priority fix in a security update and pushed out live onto large numbers of systems within hours. We were specifically aware of potential hard-forks due to signature encoding handling and had been hoping to close them via BIP62 in 0.10. BIP62's purpose is to improve transaction malleability handling and as a side effect rigidly defines the encoding for signatures, but the overall scope of BIP62 has made it take longer than we'd like to deploy. (Coincidentally, I wrote about this concern and our unique demands on cryptographic software as part of a comment on Reddit shortly before discovering that part of this OpenSSL update was actually incompatible with Bitcoin: https://www.reddit.com/r/Bitcoin/comments/2rrxq7/on_why_010s_release_notes_say_we_have_reason_to/cnitbz3 ) The patches above, however, only fix one symptom of the general problem: relying on software not designed or distributed for consensus use (in particular OpenSSL) for consensus-normative behavior. Therefore, as an incremental improvement, I propose a targeted soft-fork to enforce strict DER compliance soon, utilizing a subset of BIP62. Adding a blockchain rule for strict DER will reduce the risk of consensus inconsistencies from alternative implementations of signature parsing or signature verification, simplify BIP62, and better isolate the cryptographic validation code from the consensus algorithm. A failure to do so will likely leave us in this situation, or possibly worse, again in the future. The relevant incompatible transactions are already non-standard on the network since 0.8.0's release in February 2013, although there was seemingly a single miner still mining incompatible transactions. That miner has been contacted and has fixed their software, so a soft-fork with no chain forking should be possible. -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Bitcoin-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bitcoin-development
