From 55a4f1fc869e41aca748c63d3018f0448b1606e0 Mon Sep 17 00:00:00 2001 From: pack Date: Sun, 9 Aug 2026 10:37:07 +0000 Subject: first commit --- .../undici/lib/web/fetch/formdata-parser.js | 474 +++++++++++++++++++++ 1 file changed, 474 insertions(+) create mode 100644 node_modules/undici/lib/web/fetch/formdata-parser.js (limited to 'node_modules/undici/lib/web/fetch/formdata-parser.js') diff --git a/node_modules/undici/lib/web/fetch/formdata-parser.js b/node_modules/undici/lib/web/fetch/formdata-parser.js new file mode 100644 index 0000000..315a462 --- /dev/null +++ b/node_modules/undici/lib/web/fetch/formdata-parser.js @@ -0,0 +1,474 @@ +'use strict' + +const { isUSVString, bufferToLowerCasedHeaderName } = require('../../core/util') +const { utf8DecodeBytes } = require('./util') +const { HTTP_TOKEN_CODEPOINTS, isomorphicDecode } = require('./data-url') +const { isFileLike } = require('./file') +const { makeEntry } = require('./formdata') +const assert = require('node:assert') +const { File: NodeFile } = require('node:buffer') + +const File = globalThis.File ?? NodeFile + +const formDataNameBuffer = Buffer.from('form-data; name="') +const filenameBuffer = Buffer.from('; filename') +const dd = Buffer.from('--') +const ddcrlf = Buffer.from('--\r\n') + +/** + * @param {string} chars + */ +function isAsciiString (chars) { + for (let i = 0; i < chars.length; ++i) { + if ((chars.charCodeAt(i) & ~0x7F) !== 0) { + return false + } + } + return true +} + +/** + * @see https://andreubotella.github.io/multipart-form-data/#multipart-form-data-boundary + * @param {string} boundary + */ +function validateBoundary (boundary) { + const length = boundary.length + + // - its length is greater or equal to 27 and lesser or equal to 70, and + if (length < 27 || length > 70) { + return false + } + + // - it is composed by bytes in the ranges 0x30 to 0x39, 0x41 to 0x5A, or + // 0x61 to 0x7A, inclusive (ASCII alphanumeric), or which are 0x27 ('), + // 0x2D (-) or 0x5F (_). + for (let i = 0; i < length; ++i) { + const cp = boundary.charCodeAt(i) + + if (!( + (cp >= 0x30 && cp <= 0x39) || + (cp >= 0x41 && cp <= 0x5a) || + (cp >= 0x61 && cp <= 0x7a) || + cp === 0x27 || + cp === 0x2d || + cp === 0x5f + )) { + return false + } + } + + return true +} + +/** + * @see https://andreubotella.github.io/multipart-form-data/#multipart-form-data-parser + * @param {Buffer} input + * @param {ReturnType} mimeType + */ +function multipartFormDataParser (input, mimeType) { + // 1. Assert: mimeType’s essence is "multipart/form-data". + assert(mimeType !== 'failure' && mimeType.essence === 'multipart/form-data') + + const boundaryString = mimeType.parameters.get('boundary') + + // 2. If mimeType’s parameters["boundary"] does not exist, return failure. + // Otherwise, let boundary be the result of UTF-8 decoding mimeType’s + // parameters["boundary"]. + if (boundaryString === undefined) { + return 'failure' + } + + const boundary = Buffer.from(`--${boundaryString}`, 'utf8') + + // 3. Let entry list be an empty entry list. + const entryList = [] + + // 4. Let position be a pointer to a byte in input, initially pointing at + // the first byte. + const position = { position: 0 } + + // Note: undici addition, allows leading and trailing CRLFs. + while (input[position.position] === 0x0d && input[position.position + 1] === 0x0a) { + position.position += 2 + } + + let trailing = input.length + + while (input[trailing - 1] === 0x0a && input[trailing - 2] === 0x0d) { + trailing -= 2 + } + + if (trailing !== input.length) { + input = input.subarray(0, trailing) + } + + // 5. While true: + while (true) { + // 5.1. If position points to a sequence of bytes starting with 0x2D 0x2D + // (`--`) followed by boundary, advance position by 2 + the length of + // boundary. Otherwise, return failure. + // Note: boundary is padded with 2 dashes already, no need to add 2. + if (input.subarray(position.position, position.position + boundary.length).equals(boundary)) { + position.position += boundary.length + } else { + return 'failure' + } + + // 5.2. If position points to the sequence of bytes 0x2D 0x2D 0x0D 0x0A + // (`--` followed by CR LF) followed by the end of input, return entry list. + // Note: a body does NOT need to end with CRLF. It can end with --. + if ( + (position.position === input.length - 2 && bufferStartsWith(input, dd, position)) || + (position.position === input.length - 4 && bufferStartsWith(input, ddcrlf, position)) + ) { + return entryList + } + + // 5.3. If position does not point to a sequence of bytes starting with 0x0D + // 0x0A (CR LF), return failure. + if (input[position.position] !== 0x0d || input[position.position + 1] !== 0x0a) { + return 'failure' + } + + // 5.4. Advance position by 2. (This skips past the newline.) + position.position += 2 + + // 5.5. Let name, filename and contentType be the result of parsing + // multipart/form-data headers on input and position, if the result + // is not failure. Otherwise, return failure. + const result = parseMultipartFormDataHeaders(input, position) + + if (result === 'failure') { + return 'failure' + } + + let { name, filename, contentType, encoding } = result + + // 5.6. Advance position by 2. (This skips past the empty line that marks + // the end of the headers.) + position.position += 2 + + // 5.7. Let body be the empty byte sequence. + let body + + // 5.8. Body loop: While position is not past the end of input: + // TODO: the steps here are completely wrong + { + const boundaryIndex = input.indexOf(boundary.subarray(2), position.position) + + if (boundaryIndex === -1) { + return 'failure' + } + + body = input.subarray(position.position, boundaryIndex - 4) + + position.position += body.length + + // Note: position must be advanced by the body's length before being + // decoded, otherwise the parsing will fail. + if (encoding === 'base64') { + body = Buffer.from(body.toString(), 'base64') + } + } + + // 5.9. If position does not point to a sequence of bytes starting with + // 0x0D 0x0A (CR LF), return failure. Otherwise, advance position by 2. + if (input[position.position] !== 0x0d || input[position.position + 1] !== 0x0a) { + return 'failure' + } else { + position.position += 2 + } + + // 5.10. If filename is not null: + let value + + if (filename !== null) { + // 5.10.1. If contentType is null, set contentType to "text/plain". + contentType ??= 'text/plain' + + // 5.10.2. If contentType is not an ASCII string, set contentType to the empty string. + + // Note: `buffer.isAscii` can be used at zero-cost, but converting a string to a buffer is a high overhead. + // Content-Type is a relatively small string, so it is faster to use `String#charCodeAt`. + if (!isAsciiString(contentType)) { + contentType = '' + } + + // 5.10.3. Let value be a new File object with name filename, type contentType, and body body. + value = new File([body], filename, { type: contentType }) + } else { + // 5.11. Otherwise: + + // 5.11.1. Let value be the UTF-8 decoding without BOM of body. + value = utf8DecodeBytes(Buffer.from(body)) + } + + // 5.12. Assert: name is a scalar value string and value is either a scalar value string or a File object. + assert(isUSVString(name)) + assert((typeof value === 'string' && isUSVString(value)) || isFileLike(value)) + + // 5.13. Create an entry with name and value, and append it to entry list. + entryList.push(makeEntry(name, value, filename)) + } +} + +/** + * @see https://andreubotella.github.io/multipart-form-data/#parse-multipart-form-data-headers + * @param {Buffer} input + * @param {{ position: number }} position + */ +function parseMultipartFormDataHeaders (input, position) { + // 1. Let name, filename and contentType be null. + let name = null + let filename = null + let contentType = null + let encoding = null + + // 2. While true: + while (true) { + // 2.1. If position points to a sequence of bytes starting with 0x0D 0x0A (CR LF): + if (input[position.position] === 0x0d && input[position.position + 1] === 0x0a) { + // 2.1.1. If name is null, return failure. + if (name === null) { + return 'failure' + } + + // 2.1.2. Return name, filename and contentType. + return { name, filename, contentType, encoding } + } + + // 2.2. Let header name be the result of collecting a sequence of bytes that are + // not 0x0A (LF), 0x0D (CR) or 0x3A (:), given position. + let headerName = collectASequenceOfBytes( + (char) => char !== 0x0a && char !== 0x0d && char !== 0x3a, + input, + position + ) + + // 2.3. Remove any HTTP tab or space bytes from the start or end of header name. + headerName = removeChars(headerName, true, true, (char) => char === 0x9 || char === 0x20) + + // 2.4. If header name does not match the field-name token production, return failure. + if (!HTTP_TOKEN_CODEPOINTS.test(headerName.toString())) { + return 'failure' + } + + // 2.5. If the byte at position is not 0x3A (:), return failure. + if (input[position.position] !== 0x3a) { + return 'failure' + } + + // 2.6. Advance position by 1. + position.position++ + + // 2.7. Collect a sequence of bytes that are HTTP tab or space bytes given position. + // (Do nothing with those bytes.) + collectASequenceOfBytes( + (char) => char === 0x20 || char === 0x09, + input, + position + ) + + // 2.8. Byte-lowercase header name and switch on the result: + switch (bufferToLowerCasedHeaderName(headerName)) { + case 'content-disposition': { + // 1. Set name and filename to null. + name = filename = null + + // 2. If position does not point to a sequence of bytes starting with + // `form-data; name="`, return failure. + if (!bufferStartsWith(input, formDataNameBuffer, position)) { + return 'failure' + } + + // 3. Advance position so it points at the byte after the next 0x22 (") + // byte (the one in the sequence of bytes matched above). + position.position += 17 + + // 4. Set name to the result of parsing a multipart/form-data name given + // input and position, if the result is not failure. Otherwise, return + // failure. + name = parseMultipartFormDataName(input, position) + + if (name === null) { + return 'failure' + } + + // 5. If position points to a sequence of bytes starting with `; filename="`: + if (bufferStartsWith(input, filenameBuffer, position)) { + // Note: undici also handles filename* + let check = position.position + filenameBuffer.length + + if (input[check] === 0x2a) { + position.position += 1 + check += 1 + } + + if (input[check] !== 0x3d || input[check + 1] !== 0x22) { // =" + return 'failure' + } + + // 1. Advance position so it points at the byte after the next 0x22 (") byte + // (the one in the sequence of bytes matched above). + position.position += 12 + + // 2. Set filename to the result of parsing a multipart/form-data name given + // input and position, if the result is not failure. Otherwise, return failure. + filename = parseMultipartFormDataName(input, position) + + if (filename === null) { + return 'failure' + } + } + + break + } + case 'content-type': { + // 1. Let header value be the result of collecting a sequence of bytes that are + // not 0x0A (LF) or 0x0D (CR), given position. + let headerValue = collectASequenceOfBytes( + (char) => char !== 0x0a && char !== 0x0d, + input, + position + ) + + // 2. Remove any HTTP tab or space bytes from the end of header value. + headerValue = removeChars(headerValue, false, true, (char) => char === 0x9 || char === 0x20) + + // 3. Set contentType to the isomorphic decoding of header value. + contentType = isomorphicDecode(headerValue) + + break + } + case 'content-transfer-encoding': { + let headerValue = collectASequenceOfBytes( + (char) => char !== 0x0a && char !== 0x0d, + input, + position + ) + + headerValue = removeChars(headerValue, false, true, (char) => char === 0x9 || char === 0x20) + + encoding = isomorphicDecode(headerValue) + + break + } + default: { + // Collect a sequence of bytes that are not 0x0A (LF) or 0x0D (CR), given position. + // (Do nothing with those bytes.) + collectASequenceOfBytes( + (char) => char !== 0x0a && char !== 0x0d, + input, + position + ) + } + } + + // 2.9. If position does not point to a sequence of bytes starting with 0x0D 0x0A + // (CR LF), return failure. Otherwise, advance position by 2 (past the newline). + if (input[position.position] !== 0x0d && input[position.position + 1] !== 0x0a) { + return 'failure' + } else { + position.position += 2 + } + } +} + +/** + * @see https://andreubotella.github.io/multipart-form-data/#parse-a-multipart-form-data-name + * @param {Buffer} input + * @param {{ position: number }} position + */ +function parseMultipartFormDataName (input, position) { + // 1. Assert: The byte at (position - 1) is 0x22 ("). + assert(input[position.position - 1] === 0x22) + + // 2. Let name be the result of collecting a sequence of bytes that are not 0x0A (LF), 0x0D (CR) or 0x22 ("), given position. + /** @type {string | Buffer} */ + let name = collectASequenceOfBytes( + (char) => char !== 0x0a && char !== 0x0d && char !== 0x22, + input, + position + ) + + // 3. If the byte at position is not 0x22 ("), return failure. Otherwise, advance position by 1. + if (input[position.position] !== 0x22) { + return null // name could be 'failure' + } else { + position.position++ + } + + // 4. Replace any occurrence of the following subsequences in name with the given byte: + // - `%0A`: 0x0A (LF) + // - `%0D`: 0x0D (CR) + // - `%22`: 0x22 (") + name = new TextDecoder().decode(name) + .replace(/%0A/ig, '\n') + .replace(/%0D/ig, '\r') + .replace(/%22/g, '"') + + // 5. Return the UTF-8 decoding without BOM of name. + return name +} + +/** + * @param {(char: number) => boolean} condition + * @param {Buffer} input + * @param {{ position: number }} position + */ +function collectASequenceOfBytes (condition, input, position) { + let start = position.position + + while (start < input.length && condition(input[start])) { + ++start + } + + return input.subarray(position.position, (position.position = start)) +} + +/** + * @param {Buffer} buf + * @param {boolean} leading + * @param {boolean} trailing + * @param {(charCode: number) => boolean} predicate + * @returns {Buffer} + */ +function removeChars (buf, leading, trailing, predicate) { + let lead = 0 + let trail = buf.length - 1 + + if (leading) { + while (lead < buf.length && predicate(buf[lead])) lead++ + } + + if (trailing) { + while (trail > 0 && predicate(buf[trail])) trail-- + } + + return lead === 0 && trail === buf.length - 1 ? buf : buf.subarray(lead, trail + 1) +} + +/** + * Checks if {@param buffer} starts with {@param start} + * @param {Buffer} buffer + * @param {Buffer} start + * @param {{ position: number }} position + */ +function bufferStartsWith (buffer, start, position) { + if (buffer.length < start.length) { + return false + } + + for (let i = 0; i < start.length; i++) { + if (start[i] !== buffer[position.position + i]) { + return false + } + } + + return true +} + +module.exports = { + multipartFormDataParser, + validateBoundary +} -- cgit v1.2.3