update

httplib/parser.py

@@ -0,0 +1,160 @@
+import logging
+import re
+from urllib.parse import urlparse
+
+from httplib.exceptions import InvalidStatusLine, InvalidResponse, BadRequest
+from httplib.httpsocket import HTTPSocket
+
+
+def _get_start_line(client: HTTPSocket):
+    line = client.read_line()
+    split = list(filter(None, line.split(" ")))
+    if len(split) < 3:
+        raise InvalidStatusLine(line)  # TODO fix exception
+
+    return line, split
+
+
+def _is_valid_http_version(http_version: str):
+    if len(http_version) < 8 or http_version[4] != "/":
+        return False
+
+    (name, version) = http_version[:4], http_version[5:]
+    if name != "HTTP" or not re.match(r"1\.[0|1]", version):
+        return False
+
+
+def get_status_line(client: HTTPSocket):
+    line, (http_version, status, reason) = _get_start_line(client)
+
+    if not _is_valid_http_version(http_version):
+        raise InvalidStatusLine(line)
+    version = http_version[:4]
+
+    if not re.match(r"\d{3}", status):
+        raise InvalidStatusLine(line)
+    status = int(status)
+    if status < 100 or status > 999:
+        raise InvalidStatusLine(line)
+
+    return version, status, reason
+
+
+def parse_request_line(client: HTTPSocket):
+    line, (method, target, version) = _get_start_line(client)
+
+    if method not in ("CONNECT", "DELETE", "GET", "HEAD", "OPTIONS", "POST", "PUT", "TRACE"):
+        raise BadRequest()
+
+    if not _is_valid_http_version(version):
+        raise BadRequest()
+
+    if len(target) == "":
+        raise BadRequest()
+    parsed_target = urlparse(target)
+
+    return method, parsed_target, version
+
+
+def retrieve_headers(client: HTTPSocket):
+    raw_headers = []
+    # first header after the status-line may not contain a space
+    while True:
+        line = client.read_line()
+        if line[0].isspace():
+            continue
+        else:
+            break
+
+    while True:
+        if line in ("\r\n", "\n", " "):
+            break
+
+        if line[0].isspace():
+            raw_headers[-1] = raw_headers[-1].rstrip("\r\n")
+
+        raw_headers.append(line.lstrip())
+        line = client.read_line()
+
+    result = []
+    header_str = "".join(raw_headers)
+    for line in header_str.splitlines():
+        pos = line.find(":")
+
+        if pos <= 0 or pos >= len(line) - 1:
+            continue
+
+        (header, value) = line.split(":", 1)
+        result.append((header.lower(), value.lower()))
+
+    return result
+
+
+def parse_request_headers(client: HTTPSocket):
+    raw_headers = retrieve_headers(client)
+    headers = {}
+
+    key: str
+    for (key, value) in raw_headers:
+        if any((c.isspace()) for c in key):
+            raise BadRequest()
+
+        if key == "content-length":
+            if key in headers:
+                logging.error("Multiple content-length headers specified")
+                raise BadRequest()
+            if not value.isnumeric() or int(value) <= 0:
+                logging.error("Invalid content-length value: %r", value)
+                raise BadRequest()
+        elif key == "host":
+            if value != client.host or key in headers:
+                raise BadRequest()
+
+        headers[key] = value
+    
+    return headers
+
+
+def get_headers(client: HTTPSocket):
+    headers = []
+    # first header after the status-line may not contain a space
+    while True:
+        line = client.read_line()
+        if line[0].isspace():
+            continue
+        else:
+            break
+
+    while True:
+        if line in ("\r\n", "\n", " "):
+            break
+
+        if line[0].isspace():
+            headers[-1] = headers[-1].rstrip("\r\n")
+
+        headers.append(line.lstrip())
+        line = client.read_line()
+
+    result = {}
+    header_str = "".join(headers)
+    for line in header_str.splitlines():
+        pos = line.find(":")
+
+        if pos <= 0 or pos >= len(line) - 1:
+            continue
+
+        (header, value) = map(str.strip, line.split(":", 1))
+        check_next_header(result, header, value)
+        result[header.lower()] = value.lower()
+
+    return result
+
+
+def check_next_header(headers, next_header: str, next_value: str):
+    if next_header == "content-length":
+        if "content-length" in headers:
+            logging.error("Multiple content-length headers specified")
+            raise InvalidResponse()
+        if not next_value.isnumeric() or int(next_value) <= 0:
+            logging.error("Invalid content-length value: %r", next_value)
+            raise InvalidResponse()