mirror of
https://github.com/hanzoai/visor.git
synced 2026-09-24 17:04:14 +00:00
Etienne Perot
82e00f030e
This function reads a few binary pages from the binary during startup as a seed. Non-load-bearing, this is only used to make textproto output nondeterministic (lol, yes really). Shaves 1ms off gVisor cold start.
56 lines
1.3 KiB
Diff
56 lines
1.3 KiB
Diff
diff --git a/internal/detrand/rand.go b/internal/detrand/rand.go
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index 49c8676..d62c007 100644
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--- a/internal/detrand/rand.go
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+++ b/internal/detrand/rand.go
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@@ -9,12 +9,6 @@
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// while ensuring that the output is unstable across different builds.
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package detrand
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-import (
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- "encoding/binary"
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- "hash/fnv"
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- "os"
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-)
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-
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// Disable disables detrand such that all functions returns the zero value.
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// This function is not concurrent-safe and must be called during program init.
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func Disable() {
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@@ -34,36 +28,4 @@ func Intn(n int) int {
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return int(randSeed % uint64(n))
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}
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-// randSeed is a best-effort at an approximate hash of the Go binary.
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-var randSeed = binaryHash()
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-
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-func binaryHash() uint64 {
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- // Open the Go binary.
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- s, err := os.Executable()
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- if err != nil {
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- return 0
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- }
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- f, err := os.Open(s)
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- if err != nil {
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- return 0
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- }
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- defer f.Close()
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-
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- // Hash the size and several samples of the Go binary.
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- const numSamples = 8
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- var buf [64]byte
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- h := fnv.New64()
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- fi, err := f.Stat()
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- if err != nil {
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- return 0
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- }
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- binary.LittleEndian.PutUint64(buf[:8], uint64(fi.Size()))
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- h.Write(buf[:8])
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- for i := int64(0); i < numSamples; i++ {
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- if _, err := f.ReadAt(buf[:], i*fi.Size()/numSamples); err != nil {
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- return 0
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- }
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- h.Write(buf[:])
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- }
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- return h.Sum64()
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-}
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+var randSeed uint64
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