parent
1521baa1b7
commit
38636dfda0
@ -0,0 +1,750 @@
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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Victor Stinner <vstinner@python.org>
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Date: Fri, 15 Dec 2023 16:10:40 +0100
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Subject: [PATCH] 00415: [CVE-2023-27043] gh-102988: Reject malformed addresses
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in email.parseaddr() (#111116)
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Detect email address parsing errors and return empty tuple to
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indicate the parsing error (old API). Add an optional 'strict'
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parameter to getaddresses() and parseaddr() functions. Patch by
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Thomas Dwyer.
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Co-Authored-By: Thomas Dwyer <github@tomd.tel>
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---
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Doc/library/email.utils.rst | 19 +-
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Lib/email/utils.py | 151 ++++++++++++-
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Lib/test/test_email/test_email.py | 204 +++++++++++++++++-
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...-10-20-15-28-08.gh-issue-102988.dStNO7.rst | 8 +
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4 files changed, 361 insertions(+), 21 deletions(-)
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create mode 100644 Misc/NEWS.d/next/Library/2023-10-20-15-28-08.gh-issue-102988.dStNO7.rst
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diff --git a/Doc/library/email.utils.rst b/Doc/library/email.utils.rst
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index 63fae2ab84..d1e1898591 100644
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--- a/Doc/library/email.utils.rst
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+++ b/Doc/library/email.utils.rst
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@@ -60,13 +60,18 @@ of the new API.
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begins with angle brackets, they are stripped off.
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-.. function:: parseaddr(address)
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+.. function:: parseaddr(address, *, strict=True)
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Parse address -- which should be the value of some address-containing field such
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as :mailheader:`To` or :mailheader:`Cc` -- into its constituent *realname* and
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*email address* parts. Returns a tuple of that information, unless the parse
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fails, in which case a 2-tuple of ``('', '')`` is returned.
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+ If *strict* is true, use a strict parser which rejects malformed inputs.
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+
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+ .. versionchanged:: 3.13
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+ Add *strict* optional parameter and reject malformed inputs by default.
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+
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.. function:: formataddr(pair, charset='utf-8')
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@@ -84,12 +89,15 @@ of the new API.
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Added the *charset* option.
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-.. function:: getaddresses(fieldvalues)
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+.. function:: getaddresses(fieldvalues, *, strict=True)
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This method returns a list of 2-tuples of the form returned by ``parseaddr()``.
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*fieldvalues* is a sequence of header field values as might be returned by
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- :meth:`Message.get_all <email.message.Message.get_all>`. Here's a simple
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- example that gets all the recipients of a message::
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+ :meth:`Message.get_all <email.message.Message.get_all>`.
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+
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+ If *strict* is true, use a strict parser which rejects malformed inputs.
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+
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+ Here's a simple example that gets all the recipients of a message::
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from email.utils import getaddresses
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@@ -99,6 +107,9 @@ of the new API.
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resent_ccs = msg.get_all('resent-cc', [])
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all_recipients = getaddresses(tos + ccs + resent_tos + resent_ccs)
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+ .. versionchanged:: 3.13
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+ Add *strict* optional parameter and reject malformed inputs by default.
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+
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.. function:: parsedate(date)
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diff --git a/Lib/email/utils.py b/Lib/email/utils.py
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index 39c2240607..f83b7e5d7e 100644
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--- a/Lib/email/utils.py
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+++ b/Lib/email/utils.py
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@@ -48,6 +48,7 @@ TICK = "'"
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specialsre = re.compile(r'[][\\()<>@,:;".]')
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escapesre = re.compile(r'[\\"]')
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+
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def _has_surrogates(s):
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"""Return True if s contains surrogate-escaped binary data."""
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# This check is based on the fact that unless there are surrogates, utf8
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@@ -106,12 +107,127 @@ def formataddr(pair, charset='utf-8'):
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return address
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+def _iter_escaped_chars(addr):
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+ pos = 0
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+ escape = False
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+ for pos, ch in enumerate(addr):
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+ if escape:
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+ yield (pos, '\\' + ch)
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+ escape = False
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+ elif ch == '\\':
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+ escape = True
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+ else:
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+ yield (pos, ch)
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+ if escape:
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+ yield (pos, '\\')
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-def getaddresses(fieldvalues):
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- """Return a list of (REALNAME, EMAIL) for each fieldvalue."""
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- all = COMMASPACE.join(fieldvalues)
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- a = _AddressList(all)
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- return a.addresslist
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+
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+def _strip_quoted_realnames(addr):
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+ """Strip real names between quotes."""
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+ if '"' not in addr:
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+ # Fast path
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+ return addr
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+
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+ start = 0
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+ open_pos = None
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+ result = []
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+ for pos, ch in _iter_escaped_chars(addr):
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+ if ch == '"':
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+ if open_pos is None:
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+ open_pos = pos
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+ else:
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+ if start != open_pos:
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+ result.append(addr[start:open_pos])
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+ start = pos + 1
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+ open_pos = None
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+
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+ if start < len(addr):
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+ result.append(addr[start:])
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+
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+ return ''.join(result)
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+
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+
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+supports_strict_parsing = True
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+
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+def getaddresses(fieldvalues, *, strict=True):
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+ """Return a list of (REALNAME, EMAIL) or ('','') for each fieldvalue.
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+
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+ When parsing fails for a fieldvalue, a 2-tuple of ('', '') is returned in
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+ its place.
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+
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+ If strict is true, use a strict parser which rejects malformed inputs.
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+ """
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+
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+ # If strict is true, if the resulting list of parsed addresses is greater
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+ # than the number of fieldvalues in the input list, a parsing error has
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+ # occurred and consequently a list containing a single empty 2-tuple [('',
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+ # '')] is returned in its place. This is done to avoid invalid output.
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+ #
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+ # Malformed input: getaddresses(['alice@example.com <bob@example.com>'])
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+ # Invalid output: [('', 'alice@example.com'), ('', 'bob@example.com')]
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+ # Safe output: [('', '')]
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+
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+ if not strict:
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+ all = COMMASPACE.join(str(v) for v in fieldvalues)
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+ a = _AddressList(all)
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+ return a.addresslist
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+
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+ fieldvalues = [str(v) for v in fieldvalues]
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+ fieldvalues = _pre_parse_validation(fieldvalues)
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+ addr = COMMASPACE.join(fieldvalues)
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+ a = _AddressList(addr)
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+ result = _post_parse_validation(a.addresslist)
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+
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+ # Treat output as invalid if the number of addresses is not equal to the
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+ # expected number of addresses.
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+ n = 0
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+ for v in fieldvalues:
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+ # When a comma is used in the Real Name part it is not a deliminator.
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+ # So strip those out before counting the commas.
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+ v = _strip_quoted_realnames(v)
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+ # Expected number of addresses: 1 + number of commas
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+ n += 1 + v.count(',')
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+ if len(result) != n:
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+ return [('', '')]
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+
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+ return result
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+
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+
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+def _check_parenthesis(addr):
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+ # Ignore parenthesis in quoted real names.
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+ addr = _strip_quoted_realnames(addr)
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+
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+ opens = 0
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+ for pos, ch in _iter_escaped_chars(addr):
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+ if ch == '(':
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+ opens += 1
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+ elif ch == ')':
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+ opens -= 1
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+ if opens < 0:
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+ return False
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+ return (opens == 0)
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+
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+
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+def _pre_parse_validation(email_header_fields):
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+ accepted_values = []
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+ for v in email_header_fields:
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+ if not _check_parenthesis(v):
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+ v = "('', '')"
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+ accepted_values.append(v)
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+
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+ return accepted_values
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+
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+
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+def _post_parse_validation(parsed_email_header_tuples):
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+ accepted_values = []
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+ # The parser would have parsed a correctly formatted domain-literal
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+ # The existence of an [ after parsing indicates a parsing failure
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+ for v in parsed_email_header_tuples:
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+ if '[' in v[1]:
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+ v = ('', '')
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+ accepted_values.append(v)
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+
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+ return accepted_values
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@@ -214,16 +330,33 @@ def parsedate_to_datetime(data):
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tzinfo=datetime.timezone(datetime.timedelta(seconds=tz)))
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-def parseaddr(addr):
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+def parseaddr(addr, *, strict=True):
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"""
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Parse addr into its constituent realname and email address parts.
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Return a tuple of realname and email address, unless the parse fails, in
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which case return a 2-tuple of ('', '').
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+
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+ If strict is True, use a strict parser which rejects malformed inputs.
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"""
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- addrs = _AddressList(addr).addresslist
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- if not addrs:
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- return '', ''
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+ if not strict:
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+ addrs = _AddressList(addr).addresslist
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+ if not addrs:
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+ return ('', '')
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+ return addrs[0]
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+
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+ if isinstance(addr, list):
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+ addr = addr[0]
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+
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+ if not isinstance(addr, str):
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+ return ('', '')
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+
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+ addr = _pre_parse_validation([addr])[0]
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+ addrs = _post_parse_validation(_AddressList(addr).addresslist)
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+
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+ if not addrs or len(addrs) > 1:
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+ return ('', '')
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+
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return addrs[0]
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diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py
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index e4e40b612f..ce36efc1b1 100644
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--- a/Lib/test/test_email/test_email.py
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+++ b/Lib/test/test_email/test_email.py
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@@ -19,6 +19,7 @@ except ImportError:
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import email
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import email.policy
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+import email.utils
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from email.charset import Charset
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from email.header import Header, decode_header, make_header
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@@ -3207,15 +3208,154 @@ Foo
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[('Al Person', 'aperson@dom.ain'),
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('Bud Person', 'bperson@dom.ain')])
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+ def test_getaddresses_comma_in_name(self):
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+ """GH-106669 regression test."""
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+ self.assertEqual(
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+ utils.getaddresses(
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+ [
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+ '"Bud, Person" <bperson@dom.ain>',
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+ 'aperson@dom.ain (Al Person)',
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+ '"Mariusz Felisiak" <to@example.com>',
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+ ]
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+ ),
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+ [
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+ ('Bud, Person', 'bperson@dom.ain'),
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+ ('Al Person', 'aperson@dom.ain'),
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+ ('Mariusz Felisiak', 'to@example.com'),
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+ ],
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+ )
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+
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+ def test_parsing_errors(self):
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+ """Test for parsing errors from CVE-2023-27043 and CVE-2019-16056"""
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+ alice = 'alice@example.org'
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+ bob = 'bob@example.com'
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+ empty = ('', '')
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+
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+ # Test utils.getaddresses() and utils.parseaddr() on malformed email
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+ # addresses: default behavior (strict=True) rejects malformed address,
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+ # and strict=False which tolerates malformed address.
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+ for invalid_separator, expected_non_strict in (
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+ ('(', [(f'<{bob}>', alice)]),
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+ (')', [('', alice), empty, ('', bob)]),
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+ ('<', [('', alice), empty, ('', bob), empty]),
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+ ('>', [('', alice), empty, ('', bob)]),
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+ ('[', [('', f'{alice}[<{bob}>]')]),
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+ (']', [('', alice), empty, ('', bob)]),
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+ ('@', [empty, empty, ('', bob)]),
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+ (';', [('', alice), empty, ('', bob)]),
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+ (':', [('', alice), ('', bob)]),
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+ ('.', [('', alice + '.'), ('', bob)]),
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+ ('"', [('', alice), ('', f'<{bob}>')]),
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+ ):
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+ address = f'{alice}{invalid_separator}<{bob}>'
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+ with self.subTest(address=address):
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+ self.assertEqual(utils.getaddresses([address]),
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+ [empty])
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+ self.assertEqual(utils.getaddresses([address], strict=False),
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+ expected_non_strict)
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+
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+ self.assertEqual(utils.parseaddr([address]),
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+ empty)
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+ self.assertEqual(utils.parseaddr([address], strict=False),
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+ ('', address))
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+
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+ # Comma (',') is treated differently depending on strict parameter.
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+ # Comma without quotes.
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+ address = f'{alice},<{bob}>'
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+ self.assertEqual(utils.getaddresses([address]),
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+ [('', alice), ('', bob)])
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+ self.assertEqual(utils.getaddresses([address], strict=False),
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+ [('', alice), ('', bob)])
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+ self.assertEqual(utils.parseaddr([address]),
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+ empty)
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+ self.assertEqual(utils.parseaddr([address], strict=False),
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+ ('', address))
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+
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+ # Real name between quotes containing comma.
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+ address = '"Alice, alice@example.org" <bob@example.com>'
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+ expected_strict = ('Alice, alice@example.org', 'bob@example.com')
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+ self.assertEqual(utils.getaddresses([address]), [expected_strict])
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+ self.assertEqual(utils.getaddresses([address], strict=False), [expected_strict])
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+ self.assertEqual(utils.parseaddr([address]), expected_strict)
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+ self.assertEqual(utils.parseaddr([address], strict=False),
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+ ('', address))
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+
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+ # Valid parenthesis in comments.
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+ address = 'alice@example.org (Alice)'
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+ expected_strict = ('Alice', 'alice@example.org')
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+ self.assertEqual(utils.getaddresses([address]), [expected_strict])
|
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+ self.assertEqual(utils.getaddresses([address], strict=False), [expected_strict])
|
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+ self.assertEqual(utils.parseaddr([address]), expected_strict)
|
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+ self.assertEqual(utils.parseaddr([address], strict=False),
|
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+ ('', address))
|
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+
|
||||
+ # Invalid parenthesis in comments.
|
||||
+ address = 'alice@example.org )Alice('
|
||||
+ self.assertEqual(utils.getaddresses([address]), [empty])
|
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+ self.assertEqual(utils.getaddresses([address], strict=False),
|
||||
+ [('', 'alice@example.org'), ('', ''), ('', 'Alice')])
|
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+ self.assertEqual(utils.parseaddr([address]), empty)
|
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+ self.assertEqual(utils.parseaddr([address], strict=False),
|
||||
+ ('', address))
|
||||
+
|
||||
+ # Two addresses with quotes separated by comma.
|
||||
+ address = '"Jane Doe" <jane@example.net>, "John Doe" <john@example.net>'
|
||||
+ self.assertEqual(utils.getaddresses([address]),
|
||||
+ [('Jane Doe', 'jane@example.net'),
|
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+ ('John Doe', 'john@example.net')])
|
||||
+ self.assertEqual(utils.getaddresses([address], strict=False),
|
||||
+ [('Jane Doe', 'jane@example.net'),
|
||||
+ ('John Doe', 'john@example.net')])
|
||||
+ self.assertEqual(utils.parseaddr([address]), empty)
|
||||
+ self.assertEqual(utils.parseaddr([address], strict=False),
|
||||
+ ('', address))
|
||||
+
|
||||
+ # Test email.utils.supports_strict_parsing attribute
|
||||
+ self.assertEqual(email.utils.supports_strict_parsing, True)
|
||||
+
|
||||
def test_getaddresses_nasty(self):
|
||||
- eq = self.assertEqual
|
||||
- eq(utils.getaddresses(['foo: ;']), [('', '')])
|
||||
- eq(utils.getaddresses(
|
||||
- ['[]*-- =~$']),
|
||||
- [('', ''), ('', ''), ('', '*--')])
|
||||
- eq(utils.getaddresses(
|
||||
- ['foo: ;', '"Jason R. Mastaler" <jason@dom.ain>']),
|
||||
- [('', ''), ('Jason R. Mastaler', 'jason@dom.ain')])
|
||||
+ for addresses, expected in (
|
||||
+ (['"Sürname, Firstname" <to@example.com>'],
|
||||
+ [('Sürname, Firstname', 'to@example.com')]),
|
||||
+
|
||||
+ (['foo: ;'],
|
||||
+ [('', '')]),
|
||||
+
|
||||
+ (['foo: ;', '"Jason R. Mastaler" <jason@dom.ain>'],
|
||||
+ [('', ''), ('Jason R. Mastaler', 'jason@dom.ain')]),
|
||||
+
|
||||
+ ([r'Pete(A nice \) chap) <pete(his account)@silly.test(his host)>'],
|
||||
+ [('Pete (A nice ) chap his account his host)', 'pete@silly.test')]),
|
||||
+
|
||||
+ (['(Empty list)(start)Undisclosed recipients :(nobody(I know))'],
|
||||
+ [('', '')]),
|
||||
+
|
||||
+ (['Mary <@machine.tld:mary@example.net>, , jdoe@test . example'],
|
||||
+ [('Mary', 'mary@example.net'), ('', ''), ('', 'jdoe@test.example')]),
|
||||
+
|
||||
+ (['John Doe <jdoe@machine(comment). example>'],
|
||||
+ [('John Doe (comment)', 'jdoe@machine.example')]),
|
||||
+
|
||||
+ (['"Mary Smith: Personal Account" <smith@home.example>'],
|
||||
+ [('Mary Smith: Personal Account', 'smith@home.example')]),
|
||||
+
|
||||
+ (['Undisclosed recipients:;'],
|
||||
+ [('', '')]),
|
||||
+
|
||||
+ ([r'<boss@nil.test>, "Giant; \"Big\" Box" <bob@example.net>'],
|
||||
+ [('', 'boss@nil.test'), ('Giant; "Big" Box', 'bob@example.net')]),
|
||||
+ ):
|
||||
+ with self.subTest(addresses=addresses):
|
||||
+ self.assertEqual(utils.getaddresses(addresses),
|
||||
+ expected)
|
||||
+ self.assertEqual(utils.getaddresses(addresses, strict=False),
|
||||
+ expected)
|
||||
+
|
||||
+ addresses = ['[]*-- =~$']
|
||||
+ self.assertEqual(utils.getaddresses(addresses),
|
||||
+ [('', '')])
|
||||
+ self.assertEqual(utils.getaddresses(addresses, strict=False),
|
||||
+ [('', ''), ('', ''), ('', '*--')])
|
||||
|
||||
def test_getaddresses_embedded_comment(self):
|
||||
"""Test proper handling of a nested comment"""
|
||||
@@ -3397,6 +3537,54 @@ multipart/report
|
||||
m = cls(*constructor, policy=email.policy.default)
|
||||
self.assertIs(m.policy, email.policy.default)
|
||||
|
||||
+ def test_iter_escaped_chars(self):
|
||||
+ self.assertEqual(list(utils._iter_escaped_chars(r'a\\b\"c\\"d')),
|
||||
+ [(0, 'a'),
|
||||
+ (2, '\\\\'),
|
||||
+ (3, 'b'),
|
||||
+ (5, '\\"'),
|
||||
+ (6, 'c'),
|
||||
+ (8, '\\\\'),
|
||||
+ (9, '"'),
|
||||
+ (10, 'd')])
|
||||
+ self.assertEqual(list(utils._iter_escaped_chars('a\\')),
|
||||
+ [(0, 'a'), (1, '\\')])
|
||||
+
|
||||
+ def test_strip_quoted_realnames(self):
|
||||
+ def check(addr, expected):
|
||||
+ self.assertEqual(utils._strip_quoted_realnames(addr), expected)
|
||||
+
|
||||
+ check('"Jane Doe" <jane@example.net>, "John Doe" <john@example.net>',
|
||||
+ ' <jane@example.net>, <john@example.net>')
|
||||
+ check(r'"Jane \"Doe\"." <jane@example.net>',
|
||||
+ ' <jane@example.net>')
|
||||
+
|
||||
+ # special cases
|
||||
+ check(r'before"name"after', 'beforeafter')
|
||||
+ check(r'before"name"', 'before')
|
||||
+ check(r'b"name"', 'b') # single char
|
||||
+ check(r'"name"after', 'after')
|
||||
+ check(r'"name"a', 'a') # single char
|
||||
+ check(r'"name"', '')
|
||||
+
|
||||
+ # no change
|
||||
+ for addr in (
|
||||
+ 'Jane Doe <jane@example.net>, John Doe <john@example.net>',
|
||||
+ 'lone " quote',
|
||||
+ ):
|
||||
+ self.assertEqual(utils._strip_quoted_realnames(addr), addr)
|
||||
+
|
||||
+
|
||||
+ def test_check_parenthesis(self):
|
||||
+ addr = 'alice@example.net'
|
||||
+ self.assertTrue(utils._check_parenthesis(f'{addr} (Alice)'))
|
||||
+ self.assertFalse(utils._check_parenthesis(f'{addr} )Alice('))
|
||||
+ self.assertFalse(utils._check_parenthesis(f'{addr} (Alice))'))
|
||||
+ self.assertFalse(utils._check_parenthesis(f'{addr} ((Alice)'))
|
||||
+
|
||||
+ # Ignore real name between quotes
|
||||
+ self.assertTrue(utils._check_parenthesis(f'")Alice((" {addr}'))
|
||||
+
|
||||
|
||||
# Test the iterator/generators
|
||||
class TestIterators(TestEmailBase):
|
||||
diff --git a/Misc/NEWS.d/next/Library/2023-10-20-15-28-08.gh-issue-102988.dStNO7.rst b/Misc/NEWS.d/next/Library/2023-10-20-15-28-08.gh-issue-102988.dStNO7.rst
|
||||
new file mode 100644
|
||||
index 0000000000..3d0e9e4078
|
||||
--- /dev/null
|
||||
+++ b/Misc/NEWS.d/next/Library/2023-10-20-15-28-08.gh-issue-102988.dStNO7.rst
|
||||
@@ -0,0 +1,8 @@
|
||||
+:func:`email.utils.getaddresses` and :func:`email.utils.parseaddr` now
|
||||
+return ``('', '')`` 2-tuples in more situations where invalid email
|
||||
+addresses are encountered instead of potentially inaccurate values. Add
|
||||
+optional *strict* parameter to these two functions: use ``strict=False`` to
|
||||
+get the old behavior, accept malformed inputs.
|
||||
+``getattr(email.utils, 'supports_strict_parsing', False)`` can be use to check
|
||||
+if the *strict* paramater is available. Patch by Thomas Dwyer and Victor
|
||||
+Stinner to improve the CVE-2023-27043 fix.
|
||||
|
||||
|
||||
From 4df4fad359c280f2328b98ea9b4414f244624a58 Mon Sep 17 00:00:00 2001
|
||||
From: Lumir Balhar <lbalhar@redhat.com>
|
||||
Date: Mon, 18 Dec 2023 20:15:33 +0100
|
||||
Subject: [PATCH] Make it possible to disable strict parsing in email module
|
||||
|
||||
---
|
||||
Doc/library/email.utils.rst | 26 +++++++++++
|
||||
Lib/email/utils.py | 54 ++++++++++++++++++++++-
|
||||
Lib/test/test_email/test_email.py | 72 ++++++++++++++++++++++++++++++-
|
||||
3 files changed, 149 insertions(+), 3 deletions(-)
|
||||
|
||||
diff --git a/Doc/library/email.utils.rst b/Doc/library/email.utils.rst
|
||||
index d1e1898591..7aef773b5f 100644
|
||||
--- a/Doc/library/email.utils.rst
|
||||
+++ b/Doc/library/email.utils.rst
|
||||
@@ -69,6 +69,19 @@ of the new API.
|
||||
|
||||
If *strict* is true, use a strict parser which rejects malformed inputs.
|
||||
|
||||
+ The default setting for *strict* is set to ``True``, but you can override
|
||||
+ it by setting the environment variable ``PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING``
|
||||
+ to non-empty string.
|
||||
+
|
||||
+ Additionally, you can permanently set the default value for *strict* to
|
||||
+ ``False`` by creating the configuration file ``/etc/python/email.cfg``
|
||||
+ with the following content:
|
||||
+
|
||||
+ .. code-block:: ini
|
||||
+
|
||||
+ [email_addr_parsing]
|
||||
+ PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING = true
|
||||
+
|
||||
.. versionchanged:: 3.13
|
||||
Add *strict* optional parameter and reject malformed inputs by default.
|
||||
|
||||
@@ -97,6 +110,19 @@ of the new API.
|
||||
|
||||
If *strict* is true, use a strict parser which rejects malformed inputs.
|
||||
|
||||
+ The default setting for *strict* is set to ``True``, but you can override
|
||||
+ it by setting the environment variable ``PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING``
|
||||
+ to non-empty string.
|
||||
+
|
||||
+ Additionally, you can permanently set the default value for *strict* to
|
||||
+ ``False`` by creating the configuration file ``/etc/python/email.cfg``
|
||||
+ with the following content:
|
||||
+
|
||||
+ .. code-block:: ini
|
||||
+
|
||||
+ [email_addr_parsing]
|
||||
+ PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING = true
|
||||
+
|
||||
Here's a simple example that gets all the recipients of a message::
|
||||
|
||||
from email.utils import getaddresses
|
||||
diff --git a/Lib/email/utils.py b/Lib/email/utils.py
|
||||
index f83b7e5d7e..b8e90ceb8e 100644
|
||||
--- a/Lib/email/utils.py
|
||||
+++ b/Lib/email/utils.py
|
||||
@@ -48,6 +48,46 @@ TICK = "'"
|
||||
specialsre = re.compile(r'[][\\()<>@,:;".]')
|
||||
escapesre = re.compile(r'[\\"]')
|
||||
|
||||
+_EMAIL_CONFIG_FILE = "/etc/python/email.cfg"
|
||||
+_cached_strict_addr_parsing = None
|
||||
+
|
||||
+
|
||||
+def _use_strict_email_parsing():
|
||||
+ """"Cache implementation for _cached_strict_addr_parsing"""
|
||||
+ global _cached_strict_addr_parsing
|
||||
+ if _cached_strict_addr_parsing is None:
|
||||
+ _cached_strict_addr_parsing = _use_strict_email_parsing_impl()
|
||||
+ return _cached_strict_addr_parsing
|
||||
+
|
||||
+
|
||||
+def _use_strict_email_parsing_impl():
|
||||
+ """Returns True if strict email parsing is not disabled by
|
||||
+ config file or env variable.
|
||||
+ """
|
||||
+ disabled = bool(os.environ.get("PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING"))
|
||||
+ if disabled:
|
||||
+ return False
|
||||
+
|
||||
+ try:
|
||||
+ file = open(_EMAIL_CONFIG_FILE)
|
||||
+ except FileNotFoundError:
|
||||
+ pass
|
||||
+ else:
|
||||
+ with file:
|
||||
+ import configparser
|
||||
+ config = configparser.ConfigParser(
|
||||
+ interpolation=None,
|
||||
+ comment_prefixes=('#', ),
|
||||
+
|
||||
+ )
|
||||
+ config.read_file(file)
|
||||
+ disabled = config.getboolean('email_addr_parsing', "PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING", fallback=None)
|
||||
+
|
||||
+ if disabled:
|
||||
+ return False
|
||||
+
|
||||
+ return True
|
||||
+
|
||||
|
||||
def _has_surrogates(s):
|
||||
"""Return True if s contains surrogate-escaped binary data."""
|
||||
@@ -149,7 +189,7 @@ def _strip_quoted_realnames(addr):
|
||||
|
||||
supports_strict_parsing = True
|
||||
|
||||
-def getaddresses(fieldvalues, *, strict=True):
|
||||
+def getaddresses(fieldvalues, *, strict=None):
|
||||
"""Return a list of (REALNAME, EMAIL) or ('','') for each fieldvalue.
|
||||
|
||||
When parsing fails for a fieldvalue, a 2-tuple of ('', '') is returned in
|
||||
@@ -158,6 +198,11 @@ def getaddresses(fieldvalues, *, strict=True):
|
||||
If strict is true, use a strict parser which rejects malformed inputs.
|
||||
"""
|
||||
|
||||
+ # If default is used, it's True unless disabled
|
||||
+ # by env variable or config file.
|
||||
+ if strict == None:
|
||||
+ strict = _use_strict_email_parsing()
|
||||
+
|
||||
# If strict is true, if the resulting list of parsed addresses is greater
|
||||
# than the number of fieldvalues in the input list, a parsing error has
|
||||
# occurred and consequently a list containing a single empty 2-tuple [('',
|
||||
@@ -330,7 +375,7 @@ def parsedate_to_datetime(data):
|
||||
tzinfo=datetime.timezone(datetime.timedelta(seconds=tz)))
|
||||
|
||||
|
||||
-def parseaddr(addr, *, strict=True):
|
||||
+def parseaddr(addr, *, strict=None):
|
||||
"""
|
||||
Parse addr into its constituent realname and email address parts.
|
||||
|
||||
@@ -339,6 +384,11 @@ def parseaddr(addr, *, strict=True):
|
||||
|
||||
If strict is True, use a strict parser which rejects malformed inputs.
|
||||
"""
|
||||
+ # If default is used, it's True unless disabled
|
||||
+ # by env variable or config file.
|
||||
+ if strict == None:
|
||||
+ strict = _use_strict_email_parsing()
|
||||
+
|
||||
if not strict:
|
||||
addrs = _AddressList(addr).addresslist
|
||||
if not addrs:
|
||||
diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py
|
||||
index ce36efc1b1..05ea201b68 100644
|
||||
--- a/Lib/test/test_email/test_email.py
|
||||
+++ b/Lib/test/test_email/test_email.py
|
||||
@@ -7,6 +7,9 @@ import time
|
||||
import base64
|
||||
import unittest
|
||||
import textwrap
|
||||
+import contextlib
|
||||
+import tempfile
|
||||
+import os
|
||||
|
||||
from io import StringIO, BytesIO
|
||||
from itertools import chain
|
||||
@@ -41,7 +44,7 @@ from email import iterators
|
||||
from email import base64mime
|
||||
from email import quoprimime
|
||||
|
||||
-from test.support import unlink, start_threads
|
||||
+from test.support import unlink, start_threads, EnvironmentVarGuard, swap_attr
|
||||
from test.test_email import openfile, TestEmailBase
|
||||
|
||||
# These imports are documented to work, but we are testing them using a
|
||||
@@ -3313,6 +3316,73 @@ Foo
|
||||
# Test email.utils.supports_strict_parsing attribute
|
||||
self.assertEqual(email.utils.supports_strict_parsing, True)
|
||||
|
||||
+ def test_parsing_errors_strict_set_via_env_var(self):
|
||||
+ address = 'alice@example.org )Alice('
|
||||
+ empty = ('', '')
|
||||
+
|
||||
+ # Reset cached default value to make the function
|
||||
+ # reload the config file provided below.
|
||||
+ utils._cached_strict_addr_parsing = None
|
||||
+
|
||||
+ # Strict disabled via env variable, old behavior expected
|
||||
+ with EnvironmentVarGuard() as environ:
|
||||
+ environ["PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING"] = "1"
|
||||
+
|
||||
+ self.assertEqual(utils.getaddresses([address]),
|
||||
+ [('', 'alice@example.org'), ('', ''), ('', 'Alice')])
|
||||
+ self.assertEqual(utils.parseaddr([address]), ('', address))
|
||||
+
|
||||
+ # Clear cache again
|
||||
+ utils._cached_strict_addr_parsing = None
|
||||
+
|
||||
+ # Default strict=True, empty result expected
|
||||
+ self.assertEqual(utils.getaddresses([address]), [empty])
|
||||
+ self.assertEqual(utils.parseaddr([address]), empty)
|
||||
+
|
||||
+ # Clear cache again
|
||||
+ utils._cached_strict_addr_parsing = None
|
||||
+
|
||||
+ # Empty string in env variable = strict parsing enabled (default)
|
||||
+ with EnvironmentVarGuard() as environ:
|
||||
+ environ["PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING"] = ""
|
||||
+
|
||||
+ # Default strict=True, empty result expected
|
||||
+ self.assertEqual(utils.getaddresses([address]), [empty])
|
||||
+ self.assertEqual(utils.parseaddr([address]), empty)
|
||||
+
|
||||
+ @contextlib.contextmanager
|
||||
+ def _email_strict_parsing_conf(self):
|
||||
+ """Context for the given email strict parsing configured in config file"""
|
||||
+ with tempfile.TemporaryDirectory() as tmpdirname:
|
||||
+ filename = os.path.join(tmpdirname, 'conf.cfg')
|
||||
+ with swap_attr(utils, "_EMAIL_CONFIG_FILE", filename):
|
||||
+ with open(filename, 'w') as file:
|
||||
+ file.write('[email_addr_parsing]\n')
|
||||
+ file.write('PYTHON_EMAIL_DISABLE_STRICT_ADDR_PARSING = true')
|
||||
+ utils._EMAIL_CONFIG_FILE = filename
|
||||
+ yield
|
||||
+
|
||||
+ def test_parsing_errors_strict_disabled_via_config_file(self):
|
||||
+ address = 'alice@example.org )Alice('
|
||||
+ empty = ('', '')
|
||||
+
|
||||
+ # Reset cached default value to make the function
|
||||
+ # reload the config file provided below.
|
||||
+ utils._cached_strict_addr_parsing = None
|
||||
+
|
||||
+ # Strict disabled via config file, old results expected
|
||||
+ with self._email_strict_parsing_conf():
|
||||
+ self.assertEqual(utils.getaddresses([address]),
|
||||
+ [('', 'alice@example.org'), ('', ''), ('', 'Alice')])
|
||||
+ self.assertEqual(utils.parseaddr([address]), ('', address))
|
||||
+
|
||||
+ # Clear cache again
|
||||
+ utils._cached_strict_addr_parsing = None
|
||||
+
|
||||
+ # Default strict=True, empty result expected
|
||||
+ self.assertEqual(utils.getaddresses([address]), [empty])
|
||||
+ self.assertEqual(utils.parseaddr([address]), empty)
|
||||
+
|
||||
def test_getaddresses_nasty(self):
|
||||
for addresses, expected in (
|
||||
(['"Sürname, Firstname" <to@example.com>'],
|
||||
--
|
||||
2.43.0
|
||||
|
Loading…
Reference in new issue