ci(security): add prompt injection, base64, and secret scanning

Add CI security pipeline to catch prompt injection attacks, base64-obfuscated
payloads, leaked secrets, and .planning/ directory commits in PRs.

This is critical for get-shit-done because the entire codebase is markdown
prompts — a prompt injection in a workflow file IS the attack surface.

New files:
- scripts/prompt-injection-scan.sh: scans for instruction override, role
  manipulation, system boundary injection, DAN/jailbreak, and tool call
  injection patterns in changed files
- scripts/base64-scan.sh: extracts base64 blobs >= 40 chars, decodes them,
  and checks decoded content against injection patterns (skips data URIs
  and binary content)
- scripts/secret-scan.sh: detects AWS keys, OpenAI/Anthropic keys, GitHub
  PATs, Stripe keys, private key headers, and generic credential patterns
- .github/workflows/security-scan.yml: runs all three scans plus a
  .planning/ directory check on every PR
- .base64scanignore / .secretscanignore: per-repo false positive allowlists
- tests/security-scan.test.cjs: 51 tests covering script existence,
  pattern matching, false positive avoidance, and workflow structure

All scripts support --diff (CI), --file, and --dir modes. Cross-platform
(macOS + Linux). SHA-pinned actions. Environment variables used for
github context in run blocks (no direct interpolation).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/base64-scan.sh

@@ -0,0 +1,262 @@
+#!/usr/bin/env bash
+# base64-scan.sh — Detect base64-obfuscated prompt injection in source files
+#
+# Extracts base64 blobs >= 40 chars, decodes them, and checks decoded content
+# against the same injection patterns used by prompt-injection-scan.sh.
+#
+# Usage:
+#   scripts/base64-scan.sh --diff origin/main   # CI mode: scan changed files
+#   scripts/base64-scan.sh --file path/to/file   # Scan a single file
+#   scripts/base64-scan.sh --dir agents/          # Scan all files in a directory
+#
+# Exit codes:
+#   0 = clean
+#   1 = findings detected
+#   2 = usage error
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+MIN_BLOB_LENGTH=40
+
+# ─── Injection Patterns (decoded content) ────────────────────────────────────
+# Subset of patterns — if someone base64-encoded something, check for the
+# most common injection indicators.
+DECODED_PATTERNS=(
+  'ignore[[:space:]]+(all[[:space:]]+)?previous[[:space:]]+instructions'
+  'you[[:space:]]+are[[:space:]]+now[[:space:]]+'
+  'system[[:space:]]+prompt'
+  '</?system>'
+  '</?assistant>'
+  '\[SYSTEM\]'
+  '\[INST\]'
+  '<<SYS>>'
+  'override[[:space:]]+(system|safety|security)'
+  'pretend[[:space:]]+(you|to)[[:space:]]'
+  'act[[:space:]]+as[[:space:]]+(a|an|if)'
+  'jailbreak'
+  'bypass[[:space:]]+(safety|content|security)'
+  'eval[[:space:]]*\('
+  'exec[[:space:]]*\('
+  'rm[[:space:]]+-rf'
+  'curl[[:space:]].*\|[[:space:]]*sh'
+  'wget[[:space:]].*\|[[:space:]]*sh'
+)
+
+# ─── Ignorelist ──────────────────────────────────────────────────────────────
+
+IGNOREFILE=".base64scanignore"
+IGNORED_PATTERNS=()
+
+load_ignorelist() {
+  if [[ -f "$IGNOREFILE" ]]; then
+    while IFS= read -r line; do
+      # Skip comments and empty lines
+      [[ "$line" =~ ^[[:space:]]*# ]] && continue
+      [[ -z "${line// }" ]] && continue
+      IGNORED_PATTERNS+=("$line")
+    done < "$IGNOREFILE"
+  fi
+}
+
+is_ignored() {
+  local blob="$1"
+  if [[ ${#IGNORED_PATTERNS[@]} -eq 0 ]]; then
+    return 1
+  fi
+  for pattern in "${IGNORED_PATTERNS[@]}"; do
+    if [[ "$blob" == "$pattern" ]]; then
+      return 0
+    fi
+  done
+  return 1
+}
+
+# ─── Skip Rules ──────────────────────────────────────────────────────────────
+
+should_skip_file() {
+  local file="$1"
+  # Skip binary files
+  case "$file" in
+    *.png|*.jpg|*.jpeg|*.gif|*.ico|*.woff|*.woff2|*.ttf|*.eot|*.otf) return 0 ;;
+    *.zip|*.tar|*.gz|*.bz2|*.xz|*.7z) return 0 ;;
+    *.pdf|*.doc|*.docx|*.xls|*.xlsx) return 0 ;;
+  esac
+  # Skip lockfiles and node_modules
+  case "$file" in
+    */node_modules/*) return 0 ;;
+    */package-lock.json) return 0 ;;
+    */yarn.lock) return 0 ;;
+    */pnpm-lock.yaml) return 0 ;;
+  esac
+  # Skip the scan scripts themselves and test files
+  case "$file" in
+    */base64-scan.sh) return 0 ;;
+    */security-scan.test.cjs) return 0 ;;
+  esac
+  return 1
+}
+
+is_data_uri() {
+  local context="$1"
+  # data:image/png;base64,... or data:application/font-woff;base64,...
+  echo "$context" | grep -qE 'data:[a-zA-Z]+/[a-zA-Z0-9.+-]+;base64,' 2>/dev/null
+}
+
+# ─── File Collection ─────────────────────────────────────────────────────────
+
+collect_files() {
+  local mode="$1"
+  shift
+
+  case "$mode" in
+    --diff)
+      local base="${1:-origin/main}"
+      git diff --name-only --diff-filter=ACMR "$base"...HEAD 2>/dev/null \
+        | grep -vE '\.(png|jpg|jpeg|gif|ico|woff|woff2|ttf|eot|otf|zip|tar|gz|pdf)$' || true
+      ;;
+    --file)
+      if [[ -f "$1" ]]; then
+        echo "$1"
+      else
+        echo "Error: file not found: $1" >&2
+        exit 2
+      fi
+      ;;
+    --dir)
+      local dir="$1"
+      if [[ ! -d "$dir" ]]; then
+        echo "Error: directory not found: $dir" >&2
+        exit 2
+      fi
+      find "$dir" -type f ! -path '*/node_modules/*' ! -path '*/.git/*' ! -path '*/dist/*' \
+        ! -name '*.png' ! -name '*.jpg' ! -name '*.gif' ! -name '*.woff*' 2>/dev/null || true
+      ;;
+    --stdin)
+      cat
+      ;;
+    *)
+      echo "Usage: $0 --diff [base] | --file <path> | --dir <path> | --stdin" >&2
+      exit 2
+      ;;
+  esac
+}
+
+# ─── Scanner ─────────────────────────────────────────────────────────────────
+
+extract_and_check_blobs() {
+  local file="$1"
+  local found=0
+  local line_num=0
+
+  while IFS= read -r line; do
+    line_num=$((line_num + 1))
+
+    # Skip data URIs — legitimate base64 usage
+    if is_data_uri "$line"; then
+      continue
+    fi
+
+    # Extract base64-like blobs (alphanumeric + / + = padding, >= MIN_BLOB_LENGTH)
+    local blobs
+    blobs=$(echo "$line" | grep -oE '[A-Za-z0-9+/]{'"$MIN_BLOB_LENGTH"',}={0,3}' 2>/dev/null || true)
+
+    if [[ -z "$blobs" ]]; then
+      continue
+    fi
+
+    while IFS= read -r blob; do
+      [[ -z "$blob" ]] && continue
+
+      # Check ignorelist
+      if [[ ${#IGNORED_PATTERNS[@]} -gt 0 ]] && is_ignored "$blob"; then
+        continue
+      fi
+
+      # Try to decode — if it fails, not valid base64
+      local decoded
+      decoded=$(echo "$blob" | base64 -d 2>/dev/null || echo "")
+
+      if [[ -z "$decoded" ]]; then
+        continue
+      fi
+
+      # Check if decoded content is mostly printable text (not random binary)
+      local printable_ratio
+      local total_chars=${#decoded}
+      if [[ $total_chars -eq 0 ]]; then
+        continue
+      fi
+
+      # Count printable ASCII characters
+      local printable_count
+      printable_count=$(echo -n "$decoded" | tr -cd '[:print:]' | wc -c | tr -d ' ')
+      # Skip if less than 70% printable (likely binary data, not obfuscated text)
+      if [[ $((printable_count * 100 / total_chars)) -lt 70 ]]; then
+        continue
+      fi
+
+      # Scan decoded content against injection patterns
+      for pattern in "${DECODED_PATTERNS[@]}"; do
+        if echo "$decoded" | grep -iqE "$pattern" 2>/dev/null; then
+          if [[ $found -eq 0 ]]; then
+            echo "FAIL: $file"
+            found=1
+          fi
+          echo "  line $line_num: base64 blob decodes to suspicious content"
+          echo "    blob: ${blob:0:60}..."
+          echo "    decoded: ${decoded:0:120}"
+          echo "    matched: $pattern"
+          break
+        fi
+      done
+    done <<< "$blobs"
+  done < "$file"
+
+  return $found
+}
+
+# ─── Main ────────────────────────────────────────────────────────────────────
+
+main() {
+  if [[ $# -eq 0 ]]; then
+    echo "Usage: $0 --diff [base] | --file <path> | --dir <path>" >&2
+    exit 2
+  fi
+
+  load_ignorelist
+
+  local mode="$1"
+  shift
+
+  local files
+  files=$(collect_files "$mode" "$@")
+
+  if [[ -z "$files" ]]; then
+    echo "base64-scan: no files to scan"
+    exit 0
+  fi
+
+  local total=0
+  local failed=0
+
+  while IFS= read -r file; do
+    [[ -z "$file" ]] && continue
+    if should_skip_file "$file"; then
+      continue
+    fi
+    total=$((total + 1))
+    if ! extract_and_check_blobs "$file"; then
+      failed=$((failed + 1))
+    fi
+  done <<< "$files"
+
+  echo ""
+  echo "base64-scan: scanned $total files, $failed with findings"
+
+  if [[ $failed -gt 0 ]]; then
+    exit 1
+  fi
+  exit 0
+}
+
+main "$@"

scripts/prompt-injection-scan.sh

@@ -0,0 +1,196 @@
+#!/usr/bin/env bash
+# prompt-injection-scan.sh — Scan files for prompt injection patterns
+#
+# Usage:
+#   scripts/prompt-injection-scan.sh --diff origin/main   # CI mode: scan changed .md files
+#   scripts/prompt-injection-scan.sh --file path/to/file   # Scan a single file
+#   scripts/prompt-injection-scan.sh --dir agents/          # Scan all files in a directory
+#
+# Exit codes:
+#   0 = clean
+#   1 = findings detected
+#   2 = usage error
+set -euo pipefail
+
+# ─── Patterns ────────────────────────────────────────────────────────────────
+# Each pattern is a POSIX extended regex. Keep alphabetized by category.
+
+PATTERNS=(
+  # Instruction override
+  'ignore[[:space:]]+(all[[:space:]]+)?(previous|prior|above|earlier|preceding)[[:space:]]+(instructions|prompts|rules|directives|context)'
+  'disregard[[:space:]]+(all[[:space:]]+)?(previous|prior|above)[[:space:]]+(instructions|prompts|rules)'
+  'forget[[:space:]]+(all[[:space:]]+)?(previous|prior|above)[[:space:]]+(instructions|prompts|rules|context)'
+  'override[[:space:]]+(all[[:space:]]+)?(system|previous|safety)[[:space:]]+(instructions|prompts|rules|checks|filters|guards)'
+  'override[[:space:]]+(system|safety|security)[[:space:]]'
+
+  # Role manipulation
+  'you[[:space:]]+are[[:space:]]+now[[:space:]]+(a|an|my)[[:space:]]'
+  'from[[:space:]]+now[[:space:]]+on[[:space:]]+(you|pretend|act|behave)'
+  'pretend[[:space:]]+(you[[:space:]]+are|to[[:space:]]+be)[[:space:]]'
+  'act[[:space:]]+as[[:space:]]+(a|an|if|my)[[:space:]]'
+  'roleplay[[:space:]]+as[[:space:]]'
+  'assume[[:space:]]+the[[:space:]]+role[[:space:]]+of[[:space:]]'
+
+  # System prompt extraction
+  'output[[:space:]]+(your|the)[[:space:]]+(system[[:space:]]+)?(prompt|instructions)'
+  'reveal[[:space:]]+(your|the)[[:space:]]+(system[[:space:]]+)?(prompt|instructions)'
+  'show[[:space:]]+me[[:space:]]+(your|the)[[:space:]]+(system[[:space:]]+)?(prompt|instructions)'
+  'print[[:space:]]+(your|the)[[:space:]]+(system[[:space:]]+)?(prompt|instructions)'
+  'what[[:space:]]+(is|are)[[:space:]]+(your|the)[[:space:]]+(system[[:space:]]+)?(prompt|instructions)'
+  'repeat[[:space:]]+(your|the|all)[[:space:]]+(system[[:space:]]+)?(prompt|instructions|rules)'
+
+  # Fake message boundaries
+  '</?system>'
+  '</?assistant>'
+  '</?human>'
+  '\[SYSTEM\]'
+  '\[/SYSTEM\]'
+  '\[INST\]'
+  '\[/INST\]'
+  '<<SYS>>'
+  '<</SYS>>'
+
+  # Tool call injection / code execution in markdown
+  'eval[[:space:]]*\([[:space:]]*["\x27]'
+  'exec[[:space:]]*\([[:space:]]*["\x27]'
+  'Function[[:space:]]*\([[:space:]]*["\x27].*return'
+
+  # Jailbreak / DAN patterns
+  'do[[:space:]]+anything[[:space:]]+now'
+  'DAN[[:space:]]+mode'
+  'developer[[:space:]]+mode[[:space:]]+(enabled|output|activated)'
+  'jailbreak'
+  'bypass[[:space:]]+(safety|content|security)[[:space:]]+(filter|check|rule|guard)'
+)
+
+# ─── Allowlist ───────────────────────────────────────────────────────────────
+# Files that legitimately discuss injection patterns (security docs, tests, this script)
+ALLOWLIST=(
+  'scripts/prompt-injection-scan.sh'
+  'tests/security-scan.test.cjs'
+  'tests/security.test.cjs'
+  'tests/prompt-injection-scan.test.cjs'
+  'get-shit-done/bin/lib/security.cjs'
+  'hooks/gsd-prompt-guard.js'
+  'SECURITY.md'
+)
+
+is_allowlisted() {
+  local file="$1"
+  for allowed in "${ALLOWLIST[@]}"; do
+    if [[ "$file" == *"$allowed" ]]; then
+      return 0
+    fi
+  done
+  return 1
+}
+
+# ─── File Collection ─────────────────────────────────────────────────────────
+
+collect_files() {
+  local mode="$1"
+  shift
+
+  case "$mode" in
+    --diff)
+      local base="${1:-origin/main}"
+      # Get changed files in the diff, filter to scannable extensions
+      git diff --name-only --diff-filter=ACMR "$base"...HEAD 2>/dev/null \
+        | grep -E '\.(md|cjs|js|json|yml|yaml|sh)$' || true
+      ;;
+    --file)
+      if [[ -f "$1" ]]; then
+        echo "$1"
+      else
+        echo "Error: file not found: $1" >&2
+        exit 2
+      fi
+      ;;
+    --dir)
+      local dir="$1"
+      if [[ ! -d "$dir" ]]; then
+        echo "Error: directory not found: $dir" >&2
+        exit 2
+      fi
+      find "$dir" -type f \( -name '*.md' -o -name '*.cjs' -o -name '*.js' -o -name '*.json' -o -name '*.yml' -o -name '*.yaml' -o -name '*.sh' \) \
+        ! -path '*/node_modules/*' ! -path '*/.git/*' ! -path '*/dist/*' 2>/dev/null || true
+      ;;
+    --stdin)
+      cat
+      ;;
+    *)
+      echo "Usage: $0 --diff [base] | --file <path> | --dir <path> | --stdin" >&2
+      exit 2
+      ;;
+  esac
+}
+
+# ─── Scanner ─────────────────────────────────────────────────────────────────
+
+scan_file() {
+  local file="$1"
+  local found=0
+
+  if is_allowlisted "$file"; then
+    return 0
+  fi
+
+  for pattern in "${PATTERNS[@]}"; do
+    # Use grep -iE for case-insensitive extended regex
+    # -n for line numbers, -c for count mode first to check
+    local matches
+    matches=$(grep -inE -e "$pattern" "$file" 2>/dev/null || true)
+    if [[ -n "$matches" ]]; then
+      if [[ $found -eq 0 ]]; then
+        echo "FAIL: $file"
+        found=1
+      fi
+      echo "$matches" | while IFS= read -r line; do
+        echo "  $line"
+      done
+    fi
+  done
+
+  return $found
+}
+
+# ─── Main ────────────────────────────────────────────────────────────────────
+
+main() {
+  if [[ $# -eq 0 ]]; then
+    echo "Usage: $0 --diff [base] | --file <path> | --dir <path>" >&2
+    exit 2
+  fi
+
+  local mode="$1"
+  shift
+
+  local files
+  files=$(collect_files "$mode" "$@")
+
+  if [[ -z "$files" ]]; then
+    echo "prompt-injection-scan: no files to scan"
+    exit 0
+  fi
+
+  local total=0
+  local failed=0
+
+  while IFS= read -r file; do
+    [[ -z "$file" ]] && continue
+    total=$((total + 1))
+    if ! scan_file "$file"; then
+      failed=$((failed + 1))
+    fi
+  done <<< "$files"
+
+  echo ""
+  echo "prompt-injection-scan: scanned $total files, $failed with findings"
+
+  if [[ $failed -gt 0 ]]; then
+    exit 1
+  fi
+  exit 0
+}
+
+main "$@"

scripts/secret-scan.sh

@@ -0,0 +1,227 @@
+#!/usr/bin/env bash
+# secret-scan.sh — Check files for accidentally committed secrets/credentials
+#
+# Usage:
+#   scripts/secret-scan.sh --diff origin/main   # CI mode: scan changed files
+#   scripts/secret-scan.sh --file path/to/file   # Scan a single file
+#   scripts/secret-scan.sh --dir agents/          # Scan all files in a directory
+#
+# Exit codes:
+#   0 = clean
+#   1 = findings detected
+#   2 = usage error
+set -euo pipefail
+
+# ─── Secret Patterns ─────────────────────────────────────────────────────────
+# Format: "LABEL:::REGEX"
+# Each entry is a human label paired with a POSIX extended regex.
+
+SECRET_PATTERNS=(
+  # AWS
+  "AWS Access Key:::AKIA[0-9A-Z]{16}"
+  "AWS Secret Key:::aws_secret_access_key[[:space:]]*=[[:space:]]*[A-Za-z0-9/+=]{40}"
+
+  # OpenAI / Anthropic / AI providers
+  "OpenAI API Key:::sk-[A-Za-z0-9]{20,}"
+  "Anthropic API Key:::sk-ant-[A-Za-z0-9_-]{20,}"
+
+  # GitHub
+  "GitHub PAT:::ghp_[A-Za-z0-9]{36}"
+  "GitHub OAuth:::gho_[A-Za-z0-9]{36}"
+  "GitHub App Token:::ghs_[A-Za-z0-9]{36}"
+  "GitHub Fine-grained PAT:::github_pat_[A-Za-z0-9_]{20,}"
+
+  # Stripe
+  "Stripe Secret Key:::sk_live_[A-Za-z0-9]{24,}"
+  "Stripe Publishable Key:::pk_live_[A-Za-z0-9]{24,}"
+
+  # Generic patterns
+  "Private Key Header:::-----BEGIN[[:space:]]+(RSA|EC|DSA|OPENSSH)?[[:space:]]*PRIVATE[[:space:]]+KEY-----"
+  "Generic API Key Assignment:::api[_-]?key[[:space:]]*[:=][[:space:]]*['\"][A-Za-z0-9_-]{20,}['\"]"
+  "Generic Secret Assignment:::secret[[:space:]]*[:=][[:space:]]*['\"][A-Za-z0-9_-]{20,}['\"]"
+  "Generic Token Assignment:::token[[:space:]]*[:=][[:space:]]*['\"][A-Za-z0-9_-]{20,}['\"]"
+  "Generic Password Assignment:::password[[:space:]]*[:=][[:space:]]*['\"][^'\"]{8,}['\"]"
+
+  # Slack
+  "Slack Bot Token:::xoxb-[0-9]{10,}-[A-Za-z0-9]{20,}"
+  "Slack Webhook:::hooks\.slack\.com/services/T[A-Z0-9]{8,}/B[A-Z0-9]{8,}/[A-Za-z0-9]{24}"
+
+  # Google
+  "Google API Key:::AIza[A-Za-z0-9_-]{35}"
+
+  # NPM
+  "NPM Token:::npm_[A-Za-z0-9]{36}"
+
+  # .env file content (key=value with sensitive-looking keys)
+  "Env Variable Leak:::(DATABASE_URL|DB_PASSWORD|REDIS_URL|MONGO_URI|JWT_SECRET|SESSION_SECRET|ENCRYPTION_KEY)[[:space:]]*=[[:space:]]*[^[:space:]]{8,}"
+)
+
+# ─── Ignorelist ──────────────────────────────────────────────────────────────
+
+IGNOREFILE=".secretscanignore"
+IGNORED_FILES=()
+
+load_ignorelist() {
+  if [[ -f "$IGNOREFILE" ]]; then
+    while IFS= read -r line; do
+      [[ "$line" =~ ^[[:space:]]*# ]] && continue
+      [[ -z "${line// }" ]] && continue
+      IGNORED_FILES+=("$line")
+    done < "$IGNOREFILE"
+  fi
+}
+
+is_ignored() {
+  local file="$1"
+  if [[ ${#IGNORED_FILES[@]} -eq 0 ]]; then
+    return 1
+  fi
+  for pattern in "${IGNORED_FILES[@]}"; do
+    # Support glob-style matching
+    # shellcheck disable=SC2254
+    case "$file" in
+      $pattern) return 0 ;;
+    esac
+  done
+  return 1
+}
+
+# ─── Skip Rules ──────────────────────────────────────────────────────────────
+
+should_skip_file() {
+  local file="$1"
+  # Skip binary files
+  case "$file" in
+    *.png|*.jpg|*.jpeg|*.gif|*.ico|*.woff|*.woff2|*.ttf|*.eot|*.otf) return 0 ;;
+    *.zip|*.tar|*.gz|*.bz2|*.xz|*.7z) return 0 ;;
+    *.pdf|*.doc|*.docx|*.xls|*.xlsx) return 0 ;;
+  esac
+  # Skip lockfiles and node_modules
+  case "$file" in
+    */node_modules/*) return 0 ;;
+    */package-lock.json) return 0 ;;
+    */yarn.lock) return 0 ;;
+    */pnpm-lock.yaml) return 0 ;;
+  esac
+  # Skip the scan scripts themselves and test files
+  case "$file" in
+    */secret-scan.sh) return 0 ;;
+    */security-scan.test.cjs) return 0 ;;
+  esac
+  return 1
+}
+
+# ─── File Collection ─────────────────────────────────────────────────────────
+
+collect_files() {
+  local mode="$1"
+  shift
+
+  case "$mode" in
+    --diff)
+      local base="${1:-origin/main}"
+      git diff --name-only --diff-filter=ACMR "$base"...HEAD 2>/dev/null \
+        | grep -vE '\.(png|jpg|jpeg|gif|ico|woff|woff2|ttf|eot|otf|zip|tar|gz|pdf)$' || true
+      ;;
+    --file)
+      if [[ -f "$1" ]]; then
+        echo "$1"
+      else
+        echo "Error: file not found: $1" >&2
+        exit 2
+      fi
+      ;;
+    --dir)
+      local dir="$1"
+      if [[ ! -d "$dir" ]]; then
+        echo "Error: directory not found: $dir" >&2
+        exit 2
+      fi
+      find "$dir" -type f ! -path '*/node_modules/*' ! -path '*/.git/*' ! -path '*/dist/*' \
+        ! -name '*.png' ! -name '*.jpg' ! -name '*.gif' ! -name '*.woff*' 2>/dev/null || true
+      ;;
+    --stdin)
+      cat
+      ;;
+    *)
+      echo "Usage: $0 --diff [base] | --file <path> | --dir <path> | --stdin" >&2
+      exit 2
+      ;;
+  esac
+}
+
+# ─── Scanner ─────────────────────────────────────────────────────────────────
+
+scan_file() {
+  local file="$1"
+  local found=0
+
+  if is_ignored "$file"; then
+    return 0
+  fi
+
+  for entry in "${SECRET_PATTERNS[@]}"; do
+    local label="${entry%%:::*}"
+    local pattern="${entry#*:::}"
+
+    local matches
+    matches=$(grep -nE -e "$pattern" "$file" 2>/dev/null || true)
+    if [[ -n "$matches" ]]; then
+      if [[ $found -eq 0 ]]; then
+        echo "FAIL: $file"
+        found=1
+      fi
+      echo "$matches" | while IFS= read -r line; do
+        echo "  [$label] $line"
+      done
+    fi
+  done
+
+  return $found
+}
+
+# ─── Main ────────────────────────────────────────────────────────────────────
+
+main() {
+  if [[ $# -eq 0 ]]; then
+    echo "Usage: $0 --diff [base] | --file <path> | --dir <path>" >&2
+    exit 2
+  fi
+
+  load_ignorelist
+
+  local mode="$1"
+  shift
+
+  local files
+  files=$(collect_files "$mode" "$@")
+
+  if [[ -z "$files" ]]; then
+    echo "secret-scan: no files to scan"
+    exit 0
+  fi
+
+  local total=0
+  local failed=0
+
+  while IFS= read -r file; do
+    [[ -z "$file" ]] && continue
+    if should_skip_file "$file"; then
+      continue
+    fi
+    total=$((total + 1))
+    if ! scan_file "$file"; then
+      failed=$((failed + 1))
+    fi
+  done <<< "$files"
+
+  echo ""
+  echo "secret-scan: scanned $total files, $failed with findings"
+
+  if [[ $failed -gt 0 ]]; then
+    exit 1
+  fi
+  exit 0
+}
+
+main "$@"