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crypto.getDiffieHellman() much slower after OpenSSL 1.1.1c update #28404
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Fwiw, the commit that changed behaviour seems to be openssl/openssl@2500c09.
And assuming that this is intentional – as that commit message hints at – it might make sense to provide an asynchronous function that offloads to the threadpool for creating these objects.
Reacted by Rich Trott and Yahor SiarheyenkaAnd assuming that this is intentional – as that commit message hints at – it might make sense to provide an asynchronous function that offloads to the threadpool for creating these objects.
Yeah, it does seem as though that commit message indicates that a lot more work is now done to create DH objects and that this is by design. Close this as "not a bug"?
Yes, the commit that Anna linked to is the culprit. Before, it did 3-5 primality checks, depending on the key size; now it always does 64. That's a lot of big integer arithmetic and reading from /dev/urandom.
A new asynchronous API seems like the best way forward.
I think it is causing now my CPU to go crazy 100% on node 12.8.0
[Summary]: ticks total nonlib name 16 0.0% 0.0% JavaScript 95718 99.9% 100.0% C++ 143 0.1% 0.1% GC 63 0.1% Shared libraries 4 0.0% Unaccountedticks parent name 92138 96.2% T node::crypto::DiffieHellman::New(v8::FunctionCallbackInfo<v8::Value> const&) 92138 100.0% t __ZN2v88internal12_GLOBAL__N_125SimpleInstallGetterSetterEPNS0_7IsolateENS0_6HandleINS0_8JSObjectEEENS4_INS0_6StringEEENS0_8Builtins4NameESA_ 92138 100.0% LazyCompile: ~DiffieHellman internal/crypto/diffiehellman.js:32:23 92138 100.0% LazyCompile: ~createDiffieHellman crypto.js:126:29An application responsible for SFTP connections was timing out on new connections for us after we updated to Node 10.16.2.
While the connection is being created the event loop is blocked for 200ms on my laptop.
To isolate the issue I created a small script that opened the connection and immediatly closed it again. Here are my results for different Nodejs Versions (Node 10 and Node 12, each directly before and after the update to OpenSSL 1.1.1c):
Node 10
Node 10.16.0
[Summary]: ticks total nonlib name 32 5.9% 23.9% JavaScript 99 18.1% 73.9% C++ 7 1.3% 5.2% GC 412 75.5% Shared libraries 3 0.5% Unaccounted ticks parent name 347 63.6% /usr/local/bin/node 339 97.7% node::IsolateData::IsolateData(v8::Isolate*, uv_loop_s*, node::MultiIsolatePlatform*, unsigned int*) 160 47.2% LazyCompile: ~DiffieHellman internal/crypto/diffiehellman.js:29:23 160 100.0% LazyCompile: ~createDiffieHellman crypto.js:120:29 160 100.0% LazyCompile: ~onKEXDH_GEX_GROUP /app/node_modules/ssh2-streams/lib/ssh.js:2567:27 160 100.0% LazyCompile: ~<anonymous> /app/node_modules/ssh2-streams/lib/ssh.js:217:2110.16.1
[Summary]: ticks total nonlib name 28 0.9% 24.1% JavaScript 85 2.8% 73.3% C++ 7 0.2% 6.0% GC 2912 96.2% Shared libraries 3 0.1% Unaccounted ticks parent name 2854 94.3% /usr/local/bin/node 2842 99.6% node::IsolateData::IsolateData(v8::Isolate*, uv_loop_s*, node::MultiIsolatePlatform*, unsigned int*) 2703 95.1% LazyCompile: ~DiffieHellman internal/crypto/diffiehellman.js:29:23 2703 100.0% LazyCompile: ~createDiffieHellman crypto.js:120:29 2703 100.0% LazyCompile: ~onKEXDH_GEX_GROUP /app/node_modules/ssh2-streams/lib/ssh.js:2567:27 2703 100.0% LazyCompile: ~<anonymous> /app/node_modules/ssh2-streams/lib/ssh.js:217:21Node 12
12.4.0
[Summary]: ticks total nonlib name 0 0.0% 0.0% JavaScript 127 24.5% 100.0% C++ 4 0.8% 3.1% GC 392 75.5% Shared libraries ticks parent name 353 68.0% /usr/local/bin/node 340 96.3% node::Environment::PrintSyncTrace() const 179 52.6% LazyCompile: ~DiffieHellman internal/crypto/diffiehellman.js:32:23 179 100.0% LazyCompile: ~createDiffieHellman crypto.js:126:29 179 100.0% LazyCompile: ~onKEXDH_GEX_GROUP /app/node_modules/ssh2-streams/lib/ssh.js:2567:27 179 100.0% LazyCompile: ~<anonymous> /app/node_modules/ssh2-streams/lib/ssh.js:217:2112.5.0
[Summary]: ticks total nonlib name 0 0.0% 0.0% JavaScript 125 3.6% 100.0% C++ 5 0.1% 4.0% GC 3331 96.4% Shared libraries ticks parent name 3290 95.2% /usr/local/bin/node 3281 99.7% node::cares_wrap::(anonymous namespace)::Initialize(v8::Local<v8::Object>, v8::Local<v8::Value>, v8::Local<v8::Context>) 3135 95.6% LazyCompile: ~DiffieHellman internal/crypto/diffiehellman.js:32:23 3135 100.0% LazyCompile: ~createDiffieHellman crypto.js:126:29 3135 100.0% LazyCompile: ~onKEXDH_GEX_GROUP /app/node_modules/ssh2-streams/lib/ssh.js:2567:27 3135 100.0% LazyCompile: ~<anonymous> /app/node_modules/ssh2-streams/lib/ssh.js:217:21Reacted by Alexey TemnikovAny update on this?
I open 200 parallel ssh connections in my application. Unfortunately the devices in my network only use DiffieHellman for ssh key exchange.
With node 12.18.3 and Ubuntu 20.04 my application works properly. But with node 12.18.3 and CentOS 8.2, all the ssh connections get timed out with CPU at 100% all the time (more details here).
Any idea why my application works properly on Ubnuntu but not on CentOS with same version of node?
We can likely close this now. The Web Crypto
NODE-DHalternative uses the threadpool effectively here.import { webcrypto } from 'crypto'; const { publicKey: publicKey1, privateKey: privateKey1, } = await webcrypto.subtle.generateKey( { name: 'NODE-DH', group: 'modp18', }, true, ['deriveBits'] ); const { publicKey: publicKey2, privateKey: privateKey2, } = await webcrypto.subtle.generateKey( { name: 'NODE-DH', group: 'modp18' }, true, ['deriveKey'] ); const secret = await webcrypto.subtle.deriveBits( { name: 'NODE-DH', public: publicKey2 }, privateKey1, 256 );
This does not appear to be an issue in OpenSSL 3 / node 17 and newer. Perhaps because of this paper by @JBeatz?
$ nvm i 16; node -p process.versions.openssl; time node -e 'crypto.getDiffieHellman("modp18")' v16.16.0 is already installed. Now using node v16.16.0 (npm v8.11.0) 1.1.1q+quic real 0m16.937s user 0m16.933s sys 0m0.004s $ nvm i 17.0.0; node -p process.versions.openssl; time node -e 'crypto.getDiffieHellman("modp18")' v17.0.0 is already installed. Now using node v17.0.0 (npm v8.1.0) 3.0.0+quic real 0m0.037s user 0m0.025s sys 0m0.013s
nodecompiled from the master branch takes 24 seconds while Node.js 12.4.0 takes less than 2 seconds.@bnoordhuis notes that the default key size in 1.1.1c was increased from 1024 bits to 2048 bits, but IIUC, specifying
modp18sets the key size for both to a large value.Bug? Ot maybe it's not-a-bug because it's using a more reliable source of randomness so things are slower or something like that?
@nodejs/crypto