4d9a26498e
Paste a secret, get a link, send it. The first person to open it and press
Reveal sees the secret; the link dies at that moment. The recipient needs a
browser and nothing else — no account, no client, no installed tooling.
The server cannot read what it stores. AES-256-GCM happens in the browser and
the key lives in the URL fragment, which browsers never transmit, so hushd
holds ciphertext and no key material. That is a property of where the key sits
rather than a promise about our conduct, which is why there is deliberately no
endpoint accepting a plaintext secret and no server-side-encryption fallback:
two guarantees behind one URL would be worse than one honest guarantee.
Three decisions carry the design:
* GET /s/{id} touches NO storage, not even to check existence. Slack, Teams,
WhatsApp, iMessage and Outlook Safe Links all fetch a URL before a human
sees it, so destroying on GET would destroy most secrets in transit and the
recipient's "already used" would be indistinguishable from interception.
Only POST /reveal consumes. Bot user-agent detection is an arms race;
removing the side effect from GET is not. Pinned by
TestGettingTheRevealPageNeverConsumesTheSecret.
* Destruction is one Redis GETDEL, which is atomic. GET-then-DEL has a window
where two simultaneous readers both win, and for a one-time secret that
window is the product. The store contract demands atomicity and the same
concurrency test runs against both implementations.
* Missing, already-revealed, expired and evicted are ONE indistinguishable
410. Separating them would confirm to a prober that a given link was real.
The secret id IS the capability, so secret.ID is a struct whose every
accidental path — %v, %s, String(), slog, json.Marshal — emits a redacted
handle or refuses, and the raw value needs an explicit Value(). The first
version tried to prevent leaks by implementing no String() at all; its own test
caught that Go's fmt prints unexported fields anyway, so forbidding the method
had removed the control rather than the leak.
Operationally: structured JSON on stdout in the fleet's wire format, which
Vector already collects with no annotation; six hush_* metrics on the chassis
registry with no id, IP or path in any label; five alert rules wired into
vmalert. The public Ingress enumerates /, /s/ and /api/ so /metrics, /healthz
and /readyz share the port but are unreachable from the internet — no
basic-auth middleware to maintain and get wrong.
Dependencies are vendored because go-chassis is private: the Woodpecker test
step and the in-cluster Kaniko build both run -mod=vendor with GOPROXY=off and
hold no git credential.
cmd/hush-mcp is a stdio MCP server doing the same client-side crypto locally,
so using hush from an agent preserves the same guarantee as using it from a
browser.
80 lines
1.7 KiB
Go
80 lines
1.7 KiB
Go
package internal
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"log"
|
|
"os"
|
|
)
|
|
|
|
// TODO (ned): Revisit logging
|
|
// Add more standardized approach with log levels and configurability
|
|
|
|
type Logging interface {
|
|
Printf(ctx context.Context, format string, v ...interface{})
|
|
}
|
|
|
|
type DefaultLogger struct {
|
|
log *log.Logger
|
|
}
|
|
|
|
func (l *DefaultLogger) Printf(ctx context.Context, format string, v ...interface{}) {
|
|
_ = l.log.Output(2, fmt.Sprintf(format, v...))
|
|
}
|
|
|
|
func NewDefaultLogger() Logging {
|
|
return &DefaultLogger{
|
|
log: log.New(os.Stderr, "redis: ", log.LstdFlags|log.Lshortfile),
|
|
}
|
|
}
|
|
|
|
// Logger calls Output to print to the stderr.
|
|
// Arguments are handled in the manner of fmt.Print.
|
|
var Logger Logging = NewDefaultLogger()
|
|
|
|
var LogLevel LogLevelT = LogLevelError
|
|
|
|
// LogLevelT represents the logging level
|
|
type LogLevelT int
|
|
|
|
// Log level constants for the entire go-redis library
|
|
const (
|
|
LogLevelError LogLevelT = iota // 0 - errors only
|
|
LogLevelWarn // 1 - warnings and errors
|
|
LogLevelInfo // 2 - info, warnings, and errors
|
|
LogLevelDebug // 3 - debug, info, warnings, and errors
|
|
)
|
|
|
|
// String returns the string representation of the log level
|
|
func (l LogLevelT) String() string {
|
|
switch l {
|
|
case LogLevelError:
|
|
return "ERROR"
|
|
case LogLevelWarn:
|
|
return "WARN"
|
|
case LogLevelInfo:
|
|
return "INFO"
|
|
case LogLevelDebug:
|
|
return "DEBUG"
|
|
default:
|
|
return "UNKNOWN"
|
|
}
|
|
}
|
|
|
|
// IsValid returns true if the log level is valid
|
|
func (l LogLevelT) IsValid() bool {
|
|
return l >= LogLevelError && l <= LogLevelDebug
|
|
}
|
|
|
|
func (l LogLevelT) WarnOrAbove() bool {
|
|
return l >= LogLevelWarn
|
|
}
|
|
|
|
func (l LogLevelT) InfoOrAbove() bool {
|
|
return l >= LogLevelInfo
|
|
}
|
|
|
|
func (l LogLevelT) DebugOrAbove() bool {
|
|
return l >= LogLevelDebug
|
|
}
|