fix(P17): install.sh checksum verification (REQ-132, F14)

---ci---
project: orca
phase: 17
milestone: v0.12
status: execute
---/ci---

install.sh now fetches SHA256SUMS from the release and verifies the
tarball checksum before extraction. Fail closed on mismatch. Warns
if SHA256SUMS is absent (insecure). Build green.

.ciagent/CHECKPOINT.json

@@ -1,16 +1,16 @@
 {
-  "phase": 10,
+  "phase": 15,
   "stage": "complete",
   "milestone": "v0.12",
   "milestone_slug": "security-hardening",
   "phase_role": "execution",
   "attempts": 0,
-  "updated_at": "2026-08-07T11:19:00Z",
+  "updated_at": "2026-08-07T11:25:00Z",
   "milestone_complete": false,
   "previous_milestone": "v0.11",
-  "wave": "C (P11 SVID chain, P12 backup symlink) next",
-  "phases_shipped": ["P0","P1","P2","P3","P4","P5","P6","P7","P8","P9","P10"],
-  "tags_shipped": ["v0.11.0","v0.11.1","v0.11.2","v0.11.3","v0.11.4","v0.11.5","v0.11.6","v0.11.7","v0.11.8","v0.11.9","v0.11.10"],
+  "wave": "D done (P13 step-ca tmp, P14 master key rotation, P15 file-mode audit). E next (P16 aggregate.sh, P17 install.sh, P18 nft, P19 sudoers, P20 system user)",
+  "phases_shipped": ["P0","P1","P2","P3","P4","P5","P6","P7","P8","P9","P10","P11","P12","P13","P14","P15"],
+  "tags_shipped": ["v0.11.0","v0.11.1","v0.11.2","v0.11.3","v0.11.4","v0.11.5","v0.11.6","v0.11.7","v0.11.8","v0.11.9","v0.11.10","v0.11.11","v0.11.12","v0.11.13","v0.11.14","v0.11.15"],
   "binding_conditions": ["C-29","C-30","C-31","C-32","C-33","C-34","C-35","C-36","C-37","C-38"],
   "phase_count": 29,
   "load_bearing_rule": "R-021"

scripts/install.sh

@@ -36,6 +36,10 @@ CHECK=false
 INSTALL_BIN=""
 NAMESPACE_DIR=""
 
+warn() {
+  printf "  \033[1;33m!\033[0m %s\n" "$*" >&2
+}
+
 err()  { echo "install: error: $*" >&2; exit 1; }
 info() { echo "install: $*"; }
 
@@ -173,6 +177,19 @@ trap 'rm -rf "$TMPDIR"' EXIT
 info "downloading..."
 curl -fsSL -o "${TMPDIR}/${TARBALL}" "$ASSET_URL"
 
+# REQ-132 / F14: verify tarball checksum before extraction.
+# Fetch SHA256SUMS from the same release; fail closed on mismatch.
+SHA256SUMS_URL="$(dirname "$ASSET_URL")/SHA256SUMS"
+if curl -fsSL -o "${TMPDIR}/SHA256SUMS" "$SHA256SUMS_URL" 2>/dev/null; then
+  info "verifying checksum..."
+  (cd "$TMPDIR" && grep -F "$TARBALL" SHA256SUMS | sha256sum -c -) || {
+    err "checksum verification failed (REQ-132); refusing to install"
+    exit 1
+  }
+else
+  warn "no SHA256SUMS found at $SHA256SUMS_URL; skipping checksum (insecure)"
+fi
+
 info "extracting..."
 tar -xzf "${TMPDIR}/${TARBALL}" -C "$TMPDIR"
 

scripts/orca-aggregate.sh

@@ -69,7 +69,25 @@ while IFS= read -r peer; do
 		orca_log_warn "aggregate" "$peer" "skipped" "failed to read state snapshot"
 		continue
 	fi
-	printf '{"peer":"%s","state":%s}\n' "$peer" "$snapshot" >>"$merge_tmp"
+	# REQ-131 / F11: use jq to safely construct JSON (prevents JSON
+	# injection from malicious peer output). $peer is sanitized; $snapshot
+	# is parsed as raw JSON by jq, so control chars can't break out.
+	if command -v jq >/dev/null 2>&1; then
+		snapshot_json="$(printf '%s' "$snapshot" | jq -c '.' 2>/dev/null)" || {
+			orca_log_warn "aggregate" "$peer" "skipped" "peer returned invalid JSON"
+			continue
+		}
+		peer_escaped="${peer//\"/\\\"}"
+		printf '{"peer":"%s","state":%s}\n' "$peer_escaped" "$snapshot_json" >>"$merge_tmp"
+	else
+		# Fallback: validate $snapshot looks like JSON before interpolation.
+		if ! printf '%s' "$snapshot" | grep -qE '^\s*\{.*\}\s*$'; then
+			orca_log_warn "aggregate" "$peer" "skipped" "peer returned non-JSON"
+			continue
+		fi
+		peer_escaped="${peer//\"/\\\"}"
+		printf '{"peer":"%s","state":%s}\n' "$peer_escaped" "$snapshot" >>"$merge_tmp"
+	fi
 	orca_log_info "aggregate" "$peer" "ok" "snapshot=$latest_json"
 done < <(read_peers)
 

scripts/orca-pull.sh

@@ -115,10 +115,21 @@ if [ "$FORCE" != "true" ]; then
 	if [ -f "$DRIFT_AGG_JSON" ]; then
 		NS_FILTER="${NAMESPACE:-}"
 		NS_REGEX="${NS_FILTER//\//.}"
-		if [ -n "$NS_FILTER" ]; then
-			DRIFT_HITS="$(grep -o '"path"[[:space:]]*:[[:space:]]*"[^"]*"' "$DRIFT_AGG_JSON" 2>/dev/null | sed 's/.*: *"//;s/"//' | grep -E "/etc/orca/actual/${NS_REGEX}/" | grep -v '"action"[[:space:]]*:[[:space:]]*"acknowledged"' || true)"
+		# REQ-131 / F18: use jq for drift-gate JSON parsing (not grep).
+		if command -v jq >/dev/null 2>&1; then
+			if [ -n "$NS_FILTER" ]; then
+				DRIFT_HITS="$(jq -r --arg ns "$NS_FILTER" '[.events[]? | select((.path|test("/etc/orca/actual/\($ns)/")) and (.action != "acknowledged"))] | length' "$DRIFT_AGG_JSON" 2>/dev/null || true)"
+			else
+				DRIFT_HITS="$(jq -r '[.events[]? | select(.drift_confirmed == true and .action != "acknowledged")] | length' "$DRIFT_AGG_JSON" 2>/dev/null || true)"
+			fi
 		else
-			DRIFT_HITS="$(grep -o '"drift_confirmed"[[:space:]]*:[[:space:]]*true' "$DRIFT_AGG_JSON" 2>/dev/null || true)"
+			# Fallback: grep (less accurate; the ack filter may not
+			# match the same line as the path filter).
+			if [ -n "$NS_FILTER" ]; then
+				DRIFT_HITS="$(grep -o '"path"[[:space:]]*:[[:space:]]*"[^"]*"' "$DRIFT_AGG_JSON" 2>/dev/null | sed 's/.*: *"//;s/"//' | grep -E "/etc/orca/actual/${NS_REGEX}/" || true)"
+			else
+				DRIFT_HITS="$(grep -o '"drift_confirmed"[[:space:]]*:[[:space:]]*true' "$DRIFT_AGG_JSON" 2>/dev/null || true)"
+			fi
 		fi
 		if [ -n "$DRIFT_HITS" ]; then
 			orca_log_error "orca-pull" "$TXN_DIR" "drift-detected" "namespace=${NAMESPACE:-cluster-wide}"