Files
Panama/tests/quickshell/secrets-contract.sh
T
Gabriel Brown 8e93f08977 Show what the keyring holds, without showing what it holds
Managing a stored credential meant installing Seahorse. The keyring
rows on Privacy could say whether it was locked and nothing about what
was in it.

Four rules, each pinned by a contract, because each is a way this could
leak the thing it exists to protect:

Listing never reads values. Enumerating reports labels and attributes;
it does not ask the keyring to hand over what it is protecting.

A secret never reaches a command line. /proc makes argv readable by
every process on this machine, so a password passed as an argument is
published to all of them. The helper reads the value in process and
writes it to wl-copy on stdin.

A secret never reaches an error message, a log, or a QML property. An
exception raised while holding a password does not get to choose what
text is printed, so the clipboard tool's stderr is discarded rather
than echoed.

Forgetting one is irreversible, so the first press asks and the second
does it, and the confirming button is the only one wearing danger.

The list is collapsed until asked for: opening Privacy should not
enumerate someone's passwords as a side effect. A copied value clears
itself about a minute later, but only if the clipboard still holds it --
the guard compares a SHA-256, so the waiting process never has the
password.

Claude-Session: https://claude.ai/code/session_01BRvzt4H8XXLPVH5MyYdk9L
2026-08-19 11:14:32 -04:00

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#!/usr/bin/env bash
# A stored password must never leave the keyring except onto the clipboard,
# on purpose, one at a time.
#
# Four rules, each a way this feature could leak what it exists to protect:
#
# 1. Listing secrets must not read them. Enumerating the keyring reports
# labels and attributes; it never asks the keyring for a value.
# 2. A secret must never reach a command line. /proc makes argv readable by
# every process on the machine, so a password passed as an argument is
# published to all of them. It goes on stdin or not at all.
# 3. A secret must never reach an error message, a log, or the settings page.
# An exception raised while holding a password does not get to choose what
# text is printed.
# 4. Forgetting one is irreversible, so the page confirms first.
#
# Read-only. It lists the real keyring -- which is safe, because listing is the
# thing being verified as safe -- and never copies, deletes, or unlocks.
set -uo pipefail
repo_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
helper="$repo_dir/config/dot/quickshell/scripts/panama-keyring"
service="$repo_dir/config/dot/quickshell/services/Keyring.qml"
page="$repo_dir/config/dot/quickshell/modules/settings/PrivacyPage.qml"
fail() {
printf 'secrets contract: %s\n' "$1" >&2
exit 1
}
for path in "$helper" "$service" "$page"; do
[[ -r "$path" ]] || fail "missing $path"
done
[[ -x "$helper" ]] || fail 'panama-keyring is not executable'
# ── 1. Listing does not read values ──────────────────────────────────────────
summary_body="$(sed -n '/^def item_summary/,/^def /p' "$helper")"
[[ -n "$summary_body" ]] || fail 'item_summary is missing'
grep -qE 'load_secret|get_secret|get_text' <<<"$summary_body" \
&& fail 'the item summary reads secret values; enumerating must never require the value'
report_body="$(sed -n '/^def items_report/,/^def /p' "$helper")"
grep -qE 'load_secret|get_secret' <<<"$report_body" \
&& fail 'the item report reads secret values'
# ── 2. No secret on a command line ───────────────────────────────────────────
copy_body="$(sed -n '/^def copy_secret/,/^def /p' "$helper")"
[[ -n "$copy_body" ]] || fail 'copy_secret is missing'
grep -q 'input=encoded' <<<"$copy_body" \
|| fail 'the secret does not reach the clipboard tool on stdin'
# The value must not appear inside any argument list.
grep -qE '\[.*(secret|encoded).*\]' <<<"$copy_body" \
&& fail 'the secret appears inside a command argument list, which publishes it through /proc'
grep -q 'digest = hashlib.sha256' <<<"$copy_body" \
|| fail 'the clipboard is cleared without comparing a hash, so it either holds the secret or clears the wrong thing'
grep -qE 'Popen\(.*secret|Popen\(.*encoded' <<<"$copy_body" \
&& fail 'the clipboard-clearing process is handed the secret'
# ── 3. No secret in output ───────────────────────────────────────────────────
grep -qE '^\s*print\((secret|value|encoded)' <<<"$copy_body" \
&& fail 'the secret is printed'
grep -q 'completed.stderr' <<<"$copy_body" \
&& fail "the clipboard tool's stderr is echoed while a secret is in hand"
# The service must not hold one either.
grep -qiE 'property (string|var) (secret|password|value)\b' "$service" \
&& fail 'the Keyring service declares a property that would hold a secret value'
# ── 4. Forgetting is confirmed ───────────────────────────────────────────────
grep -q 'confirmingPath' "$page" \
|| fail 'the page deletes a stored secret without a confirmation step'
grep -q 'Keyring.forget(' "$page" \
|| fail 'the page cannot forget a secret at all'
# The guard itself, not merely the word "confirming" somewhere nearby: the
# button's own label and tone both mention it, so proximity proves nothing.
# What must exist is the early return that turns the FIRST press into a request
# for confirmation rather than a deletion.
grep -q 'if (!secretRow.confirming)' "$page" \
|| fail 'the first press on Forget is not turned into a confirmation step'
grep -q 'root.confirmingPath = secretRow.itemPath;' "$page" \
|| fail 'nothing records which item is awaiting confirmation'
# Opening the page must not enumerate anyone's passwords as a side effect.
grep -qE 'Component.onCompleted:.*Keyring.list\(\)' "$page" \
&& fail 'the page lists stored secrets when it opens rather than when asked'
# ── The list itself, on the real keyring ─────────────────────────────────────
command -v jq >/dev/null 2>&1 || { printf 'secrets contract: SKIP (no jq)\n'; exit 0; }
listing="$("$helper" items 2>/dev/null)" || fail 'listing stored secrets failed'
jq -e '.collections | type == "array"' <<<"$listing" >/dev/null \
|| fail 'the listing has no collections'
# No field anywhere in the payload may be named like a value.
offenders="$(jq -r '[paths | map(tostring) | join(".")] | map(select(test("(secret|password|value|token)$";"i"))) | join(", ")' <<<"$listing")"
[[ -z "$offenders" ]] || fail "the listing carries value-shaped fields: $offenders"
# Every item reports where it came from, so a row can be identified without it.
jq -e '[.collections[].items[] | (.path | startswith("/org/freedesktop/secrets/")) and (.label | length > 0)] | all' \
<<<"$listing" >/dev/null || fail 'an item is missing its path or label'
# ── Refusals ─────────────────────────────────────────────────────────────────
# A refused path must not reach the clipboard at all, which is checked by
# stubbing the clipboard tool rather than inferred from an exit code -- the
# helper answers with the item list plus an error field, so its exit status is
# deliberately 0 even when it refuses.
work="$(mktemp -d /tmp/panama-secrets.XXXXXX)"
trap 'rm -rf "$work"' EXIT
mkdir -p "$work/bin"
cat >"$work/bin/wl-copy" <<'STUB'
#!/usr/bin/env bash
printf 'called: %s\n' "$*" >>"$PANAMA_SECRETS_CALL_LOG"
cat >>"$PANAMA_SECRETS_CALL_LOG"
STUB
chmod +x "$work/bin/wl-copy"
export PANAMA_SECRETS_CALL_LOG="$work/calls"
: >"$PANAMA_SECRETS_CALL_LOG"
refusal() {
PATH="$work/bin:$PATH" "$helper" "$@" 2>/dev/null | jq -r '.error // ""'
}
[[ -n "$(refusal copy /etc/passwd)" ]] \
|| fail 'copy accepted a path that is not a stored secret'
[[ -n "$(refusal copy ../../etc/passwd)" ]] \
|| fail 'copy accepted a relative path'
[[ -n "$(refusal copy /org/freedesktop/secrets/collection/login)" ]] \
|| fail 'copy accepted a collection path rather than an item'
[[ -n "$(refusal forget /org/freedesktop/secrets/collection/login)" ]] \
|| fail 'forget accepted a collection path, which would delete a whole keyring'
[[ -n "$(refusal copy /org/freedesktop/secrets/collection/login/999999)" ]] \
|| fail 'copy accepted an item that does not exist'
[[ ! -s "$PANAMA_SECRETS_CALL_LOG" ]] \
|| fail 'a refused request still reached the clipboard'
PATH="$work/bin:$PATH" "$helper" copy >/dev/null 2>&1 \
&& fail 'copy with no argument was accepted'
[[ ! -s "$PANAMA_SECRETS_CALL_LOG" ]] \
|| fail 'a malformed request still reached the clipboard'
printf 'secrets contract: PASS (%d items listed, none readable from the listing)\n' \
"$(jq '[.collections[].items[]] | length' <<<"$listing")"