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.
81 lines
2.3 KiB
Go
81 lines
2.3 KiB
Go
// Copyright The Prometheus Authors
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package procfs
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"strconv"
|
|
|
|
fsi "github.com/prometheus/procfs/internal/fs"
|
|
)
|
|
|
|
// Provide access to /proc/PID/task/TID files, for thread specific values. Since
|
|
// such files have the same structure as /proc/PID/ ones, the data structures
|
|
// and the parsers for the latter may be reused.
|
|
|
|
// AllThreads returns a list of all currently available threads under /proc/PID.
|
|
func AllThreads(pid int) (Procs, error) {
|
|
fs, err := NewFS(DefaultMountPoint)
|
|
if err != nil {
|
|
return Procs{}, err
|
|
}
|
|
return fs.AllThreads(pid)
|
|
}
|
|
|
|
// AllThreads returns a list of all currently available threads for PID.
|
|
func (fs FS) AllThreads(pid int) (Procs, error) {
|
|
taskPath := fs.proc.Path(strconv.Itoa(pid), "task")
|
|
d, err := os.Open(taskPath)
|
|
if err != nil {
|
|
return Procs{}, err
|
|
}
|
|
defer d.Close()
|
|
|
|
names, err := d.Readdirnames(-1)
|
|
if err != nil {
|
|
return Procs{}, fmt.Errorf("%w: could not read %q: %w", ErrFileRead, d.Name(), err)
|
|
}
|
|
|
|
t := Procs{}
|
|
for _, n := range names {
|
|
tid, err := strconv.ParseInt(n, 10, 64)
|
|
if err != nil {
|
|
continue
|
|
}
|
|
|
|
t = append(t, Proc{PID: int(tid), fs: FS{fsi.FS(taskPath), fs.isReal}})
|
|
}
|
|
|
|
return t, nil
|
|
}
|
|
|
|
// Thread returns a process for a given PID, TID.
|
|
func (fs FS) Thread(pid, tid int) (Proc, error) {
|
|
taskPath := fs.proc.Path(strconv.Itoa(pid), "task")
|
|
if _, err := os.Stat(taskPath); err != nil {
|
|
return Proc{}, err
|
|
}
|
|
return Proc{PID: tid, fs: FS{fsi.FS(taskPath), fs.isReal}}, nil
|
|
}
|
|
|
|
// Thread returns a process for a given TID of Proc.
|
|
func (proc Proc) Thread(tid int) (Proc, error) {
|
|
tfs := FS{fsi.FS(proc.path("task")), proc.fs.isReal}
|
|
if _, err := os.Stat(tfs.proc.Path(strconv.Itoa(tid))); err != nil {
|
|
return Proc{}, err
|
|
}
|
|
return Proc{PID: tid, fs: tfs}, nil
|
|
}
|