diff options
| author | Marc Mutz <marc.mutz@qt.io> | 2024-04-18 16:14:46 +0200 |
|---|---|---|
| committer | Marc Mutz <marc.mutz@qt.io> | 2024-05-03 01:05:07 +0200 |
| commit | 834e7d60a9cb67a1d445151a4f7c34d4288db01b (patch) | |
| tree | d92cf48cc907ec638113aab6b3e8924cbf88239e /src/network/access/qrestreply.cpp | |
| parent | e53df7a0218ff2d88668a33a0d9cf8bbe40e4933 (diff) | |
QRestReply: allow comments where white-space is allowed
This is RFC2822 grammar (except that line folding is not
allowed).
RFC9110 doesn't allow it anymore, but it might make sense to accept it
nonetheless (Postel's Law).
Pick-to: 6.7
Task-number: QTBUG-123544
Change-Id: Ie990cd332c7603dbdae29c19b2804bd33a058ca0
Reviewed-by: Juha Vuolle <juha.vuolle@qt.io>
Diffstat (limited to 'src/network/access/qrestreply.cpp')
| -rw-r--r-- | src/network/access/qrestreply.cpp | 64 |
1 files changed, 56 insertions, 8 deletions
diff --git a/src/network/access/qrestreply.cpp b/src/network/access/qrestreply.cpp index 155e5877fdc..cdd264ba6eb 100644 --- a/src/network/access/qrestreply.cpp +++ b/src/network/access/qrestreply.cpp @@ -420,6 +420,54 @@ static constexpr bool is_tchar(char ch) noexcept } } +static constexpr auto parse_comment(QByteArrayView data) noexcept +{ + struct R { + QByteArrayView comment, tail; + constexpr explicit operator bool() const noexcept { return !comment.isEmpty(); } + }; + + const auto invalid = R{{}, data}; // preserves original `data` + + // comment = "(" *( ctext / quoted-pair / comment ) ")" + // ctext = HTAB / SP / %x21-27 / %x2A-5B / %x5D-7E / obs-text + + if (!data.startsWith('(')) + return invalid; + + qsizetype i = 1; + qsizetype level = 1; + while (i < data.size()) { + switch (data[i++]) { + case '(': // nested comment + ++level; + break; + case ')': // end of comment + if (--level == 0) + return R{data.first(i), data.sliced(i)}; + break; + case '\\': // quoted-pair + if (i == data.size()) + return invalid; // premature end + ++i; // eat escaped character + break; + default: + ; // don't validate ctext - accept everything (Postel's Law) + } + } + + return invalid; // premature end / unbalanced nesting levels +} + +static constexpr void eat_CWS(QByteArrayView &data) noexcept +{ + eat_OWS(data); + while (const auto comment = parse_comment(data)) { + data = comment.tail; + eat_OWS(data); + } +} + static constexpr auto parse_token(QByteArrayView data) noexcept { struct R { @@ -452,13 +500,13 @@ static constexpr auto parse_parameter(QByteArrayView data, qxp::function_ref<voi return invalid; data = name.tail; - eat_OWS(data); // not in the grammar, but accepted under Postel's Law + eat_CWS(data); // not in the grammar, but accepted under Postel's Law if (!data.startsWith('=')) return invalid; data = data.sliced(1); - eat_OWS(data); // not in the grammar, but accepted under Postel's Law + eat_CWS(data); // not in the grammar, but accepted under Postel's Law if (Q_UNLIKELY(data.startsWith('"'))) { // value is a quoted-string @@ -488,27 +536,27 @@ static auto parse_content_type(QByteArrayView data) constexpr explicit operator bool() const noexcept { return !type.isEmpty(); } }; - eat_OWS(data); // not in the grammar, but accepted under Postel's Law + eat_CWS(data); // not in the grammar, but accepted under Postel's Law const auto type = parse_token(data); if (!type) return R{}; data = type.tail; - eat_OWS(data); // not in the grammar, but accepted under Postel's Law + eat_CWS(data); // not in the grammar, but accepted under Postel's Law if (!data.startsWith('/')) return R{}; data = data.sliced(1); - eat_OWS(data); // not in the grammar, but accepted under Postel's Law + eat_CWS(data); // not in the grammar, but accepted under Postel's Law const auto subtype = parse_token(data); if (!subtype) return R{}; data = subtype.tail; - eat_OWS(data); + eat_CWS(data); auto r = R{QLatin1StringView{type.token}, QLatin1StringView{subtype.token}, {}}; @@ -516,7 +564,7 @@ static auto parse_content_type(QByteArrayView data) data = data.sliced(1); // eat ';' - eat_OWS(data); + eat_CWS(data); const auto param = parse_parameter(data, [&](char ch) { r.charset.append(1, ch); }); if (param.name.compare("charset"_L1, Qt::CaseInsensitive) == 0) { @@ -530,7 +578,7 @@ static auto parse_content_type(QByteArrayView data) // otherwise, continue (accepting e.g. `;;`) data = param.tail; - eat_OWS(data); + eat_CWS(data); } return r; // no charset found |