#!/bin/bash
# 11 - Timing Oracle Tests
# Methodology: 30-sample mean + stddev per group; signal is real if |diff| > 3*stddev
# Covers HTTP/1.1, HTTP/2, constant-time auth, padding oracle

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "$SCRIPT_DIR/../config.sh"
OUT_FILE="$OUT/11_timing_oracle.txt"

# --local flag: tighten threshold when running inside same datacenter/VPN
# Remote internet jitter is ~20-50ms; local jitter is ~1-5ms
# Default threshold = 3σ with min 15ms floor
# --local threshold = 3σ with min 3ms floor (catches subtle constant-time violations)
LOCAL_MODE="${LOCAL_MODE:-0}"
if [ "$LOCAL_MODE" = "1" ]; then
  TIMING_FLOOR=3
  echo "Mode: LOCAL — timing floor 3ms (tight, for same-datacenter runs)" | tee -a "$OUT_FILE"
else
  TIMING_FLOOR=15
  echo "Mode: REMOTE — timing floor 15ms (guards against internet jitter)" | tee -a "$OUT_FILE"
fi
echo "=== 11. Timing Oracle Tests ===" | tee "$OUT_FILE"
echo "Methodology: 50 samples per group, mean ± stddev, signal threshold = 3σ" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

# ── timing harness ────────────────────────────────────────────────────────────
# Returns space-separated list of ms timings
sample_times() {
  local n="$1"; shift
  local times=""
  for i in $(seq 1 "$n"); do
    T=$(python3 -c "import time; print(int(time.time()*1000))")
    curl -sk -o /dev/null --max-time 15 "$@" 2>/dev/null
    E=$(python3 -c "import time; print(int(time.time()*1000))")
    times="$times $((E - T))"
  done
  echo "$times"
}

# Compute mean and stddev from space-separated ms list
stats() {
  python3 -c "
import sys, math, statistics
vals = [int(x) for x in sys.stdin.read().split() if x]
if not vals: print('N=0 mean=0 stddev=0'); sys.exit()
m = statistics.mean(vals)
s = statistics.pstdev(vals) if len(vals) > 1 else 0
print(f'N={len(vals)} mean={m:.1f}ms stddev={s:.1f}ms min={min(vals)}ms max={max(vals)}ms')
"
}

compare_groups() {
  # compare_groups "label_a" times_a "label_b" times_b
  local la="$1" ta="$2" lb="$3" tb="$4"
  python3 -c "
import sys, math, statistics
la,ta,lb,tb = sys.argv[1], sys.argv[2], sys.argv[3], sys.argv[4]
a = [int(x) for x in ta.split() if x]
b = [int(x) for x in tb.split() if x]
if not a or not b: print('    [SKIP] insufficient data'); sys.exit()
ma, mb = statistics.mean(a), statistics.mean(b)
sa = statistics.pstdev(a) if len(a)>1 else 1
sb = statistics.pstdev(b) if len(b)>1 else 1
diff = abs(ma - mb)
import os
  floor = int(os.environ.get("TIMING_FLOOR", "15"))
  threshold = 3 * max(sa, sb, floor)
verdict = 'TIMING-LEAK' if diff > threshold else 'OK'
print(f'    [{verdict}] {la}: {ma:.1f}ms±{sa:.1f}  vs  {lb}: {mb:.1f}ms±{sb:.1f}  diff={diff:.1f}ms threshold={threshold:.1f}ms')
" "$la" "$ta" "$lb" "$tb"
}

SAMPLES=50

# ── 1. API Key Timing Oracle ──────────────────────────────────────────────────
echo "--- API Key Timing Oracle (HTTP/2, $SAMPLES samples each) ---" | tee -a "$OUT_FILE"
echo "  Sampling invalid key..." | tee -a "$OUT_FILE"
T_INVALID=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Authorization: Bearer INVALID_KEY_XXXXXXXXXXX' \
  -H 'Content-Type: application/json' \
  -d '{"data":"test","algorithm":"classical"}' \
  "$API_TARGET/encrypt")
echo "  Invalid key: $(echo "$T_INVALID" | stats)" | tee -a "$OUT_FILE"

echo "  Sampling no-key (missing header)..." | tee -a "$OUT_FILE"
T_NOKEY=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Content-Type: application/json' \
  -d '{"data":"test","algorithm":"classical"}' \
  "$API_TARGET/encrypt")
echo "  No key:      $(echo "$T_NOKEY" | stats)" | tee -a "$OUT_FILE"

echo "  Sampling malformed key (wrong prefix)..." | tee -a "$OUT_FILE"
T_MALFORMED=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Authorization: Basic INVALID_BASE64==' \
  -H 'Content-Type: application/json' \
  -d '{"data":"test","algorithm":"classical"}' \
  "$API_TARGET/encrypt")
echo "  Malformed:   $(echo "$T_MALFORMED" | stats)" | tee -a "$OUT_FILE"

compare_groups "invalid-key" "$T_INVALID" "no-key" "$T_NOKEY" | tee -a "$OUT_FILE"
compare_groups "invalid-key" "$T_INVALID" "malformed-key" "$T_MALFORMED" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

# ── 2. Admin Login Username Enumeration ───────────────────────────────────────
echo "--- Admin Login Timing Oracle ($SAMPLES samples each) ---" | tee -a "$OUT_FILE"
echo "  Sampling likely-valid username 'admin'..." | tee -a "$OUT_FILE"
T_ADMIN=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Content-Type: application/x-www-form-urlencoded' \
  -d 'username=admin&password=wrongpassword_xyz_pentest' \
  "$TARGET/admin/")
echo "  'admin':       $(echo "$T_ADMIN" | stats)" | tee -a "$OUT_FILE"

echo "  Sampling nonexistent username..." | tee -a "$OUT_FILE"
T_NOUSER=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Content-Type: application/x-www-form-urlencoded' \
  -d 'username=nonexistent_user_xyz_1234&password=wrongpassword_xyz_pentest' \
  "$TARGET/admin/")
echo "  nonexistent:   $(echo "$T_NOUSER" | stats)" | tee -a "$OUT_FILE"

compare_groups "admin" "$T_ADMIN" "nonexistent" "$T_NOUSER" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

# ── 3. Decrypt Padding Oracle ─────────────────────────────────────────────────
echo "--- Decrypt Padding Oracle ($SAMPLES samples each) ---" | tee -a "$OUT_FILE"
SHORT_B64="aGVsbG8="  # "hello" — too short, invalid ciphertext
LONG_B64=$(python3 -c "import base64; print(base64.b64encode(b'X'*512).decode())")

echo "  Sampling short invalid ciphertext..." | tee -a "$OUT_FILE"
T_SHORT=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Content-Type: application/json' \
  -d "{\"data\":\"$SHORT_B64\",\"algorithm\":\"classical\"}" \
  "$API_TARGET/decrypt")
echo "  Short (8b):  $(echo "$T_SHORT" | stats)" | tee -a "$OUT_FILE"

echo "  Sampling long invalid ciphertext..." | tee -a "$OUT_FILE"
T_LONG=$(sample_times $SAMPLES \
  -X POST --http2 \
  -H 'Content-Type: application/json' \
  -d "{\"data\":\"$LONG_B64\",\"algorithm\":\"classical\"}" \
  "$API_TARGET/decrypt")
echo "  Long (512b): $(echo "$T_LONG" | stats)" | tee -a "$OUT_FILE"

compare_groups "short-ciphertext" "$T_SHORT" "long-ciphertext" "$T_LONG" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

# ── 4. HTTP/1.1 vs HTTP/2 Timing Baseline ────────────────────────────────────
echo "--- Protocol Timing Baseline (HTTP/1.1 vs HTTP/2, $SAMPLES samples) ---" | tee -a "$OUT_FILE"
echo "  HTTP/1.1..." | tee -a "$OUT_FILE"
T_H1=$(sample_times $SAMPLES --http1.1 "$TARGET/")
echo "  HTTP/1.1: $(echo "$T_H1" | stats)" | tee -a "$OUT_FILE"

echo "  HTTP/2..." | tee -a "$OUT_FILE"
T_H2=$(sample_times $SAMPLES --http2 "$TARGET/")
echo "  HTTP/2:   $(echo "$T_H2" | stats)" | tee -a "$OUT_FILE"

compare_groups "HTTP/1.1" "$T_H1" "HTTP/2" "$T_H2" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

# ── 5. WAF Timing — blocked vs clean ─────────────────────────────────────────
echo "--- WAF Timing Oracle (blocked vs clean, $SAMPLES samples) ---" | tee -a "$OUT_FILE"
echo "  Clean request..." | tee -a "$OUT_FILE"
T_CLEAN=$(sample_times $SAMPLES --http2 -A "$BROWSER_UA" "$TARGET/")
echo "  Clean:   $(echo "$T_CLEAN" | stats)" | tee -a "$OUT_FILE"

echo "  Blocked (SQLi) request..." | tee -a "$OUT_FILE"
T_BLOCKED=$(sample_times $SAMPLES --http2 -A "$BROWSER_UA" \
  "$TARGET/?q=$(python3 -c "import urllib.parse; print(urllib.parse.quote(\"' OR 1=1--\"))")")
echo "  Blocked: $(echo "$T_BLOCKED" | stats)" | tee -a "$OUT_FILE"

compare_groups "clean" "$T_CLEAN" "waf-blocked" "$T_BLOCKED" | tee -a "$OUT_FILE"
echo "  (significant diff = WAF adds measurable latency — timing side-channel)" | tee -a "$OUT_FILE"
echo "" | tee -a "$OUT_FILE"

echo "=== 11. Timing Oracle COMPLETE ===" | tee -a "$OUT_FILE"