package stupidgcm import ( "runtime" "golang.org/x/sys/cpu" ) // PreferOpenSSL tells us if OpenSSL is faster than Go GCM on this machine. // // Go GCM is only faster if the CPU either: // // 1) Is X86_64 && has AES instructions && Go is v1.6 or higher // 2) Is ARM64 && has AES instructions && Go is v1.11 or higher // (commit https://github.com/golang/go/commit/4f1f503373cda7160392be94e3849b0c9b9ebbda) // // See https://github.com/rfjakob/gocryptfs/wiki/CPU-Benchmarks // for benchmarks. func PreferOpenSSL() bool { if BuiltWithoutOpenssl { return false } // Safe to call on other architectures - will just read false. if cpu.X86.HasAES || cpu.ARM64.HasAES { // Go stdlib is probably faster return false } // On the Apple M1, Go stdlib is faster than OpenSSL, despite cpu.ARM64.HasAES // reading false: https://github.com/rfjakob/gocryptfs/issues/556#issuecomment-848079309 if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" { return false } // OpenSSL is probably faster return true }