| 122 | |
| 123 | |
| 124 | def _read_chunked_body(rfile: _Readable, max_bytes: int) -> bytes: |
| 125 | chunks: list[bytes] = [] |
| 126 | total = 0 |
| 127 | while True: |
| 128 | size_line = rfile.readline(_MAX_CHUNK_SIZE_LINE) |
| 129 | if not size_line: |
| 130 | raise ValueError( |
| 131 | "could not read chunk size: unexpected end of stream" |
| 132 | ) |
| 133 | size_token = size_line.split(b";", 1)[0].strip() |
| 134 | try: |
| 135 | chunk_size = int(size_token, 16) |
| 136 | except ValueError as exc: |
| 137 | raise ValueError(f"invalid chunk size: {size_token!r}") from exc |
| 138 | if chunk_size == 0: |
| 139 | # Drain trailer headers up to the terminating blank line. Bounded |
| 140 | # so a hostile peer cannot pin the connection with endless lines. |
| 141 | trailer_total = 0 |
| 142 | while True: |
| 143 | trailer = rfile.readline(_MAX_CHUNK_SIZE_LINE) |
| 144 | if trailer in (b"\r\n", b"\n", b""): |
| 145 | break |
| 146 | trailer_total += len(trailer) |
| 147 | if trailer_total > _MAX_TRAILER_BYTES: |
| 148 | raise ValueError( |
| 149 | "chunked request trailer exceeds maximum size" |
| 150 | ) |
| 151 | break |
| 152 | total += chunk_size |
| 153 | if total > max_bytes: |
| 154 | raise ValueError("chunked request body exceeds maximum size") |
| 155 | data = rfile.read(chunk_size) |
| 156 | if len(data) != chunk_size: |
| 157 | raise ValueError( |
| 158 | "could not read full chunk: unexpected end of stream" |
| 159 | ) |
| 160 | chunks.append(data) |
| 161 | rfile.readline(_MAX_CHUNK_SIZE_LINE) |
| 162 | return b"".join(chunks) |