Skip to content

Fix exception that occurs with libc++ regex engine #368

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Feb 28, 2020
Merged

Fix exception that occurs with libc++ regex engine #368

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion httplib.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1764,7 +1764,7 @@ inline bool read_headers(Stream &strm, Headers &headers) {
// the left or right side of the header value:
// - https://stackoverflow.com/questions/50179659/
// - https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html
static const std::regex re(R"((.+?):[\t ]*(.+))");
static const std::regex re(R"(([^:]+):[\t ]*(.+))");

std::cmatch m;
if (std::regex_match(line_reader.ptr(), end, m, re)) {
Expand Down
56 changes: 49 additions & 7 deletions test/test.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2049,7 +2049,8 @@ TEST(ServerRequestParsingTest, TrimWhitespaceFromHeaderValues) {
EXPECT_EQ(header_value, "\v bar \e");
}

TEST(ServerRequestParsingTest, ReadHeadersRegexComplexity) {
// Sends a raw request and verifies that there isn't a crash or exception.
static void test_raw_request(const std::string& req) {
Server svr;
svr.Get("/hi", [&](const Request & /*req*/, Response &res) {
res.set_content("ok", "text/plain");
Expand All @@ -2066,17 +2067,58 @@ TEST(ServerRequestParsingTest, ReadHeadersRegexComplexity) {
std::this_thread::sleep_for(std::chrono::milliseconds(1));
}

ASSERT_TRUE(send_request(client_read_timeout_sec, req));
svr.stop();
t.join();
EXPECT_TRUE(listen_thread_ok);
}

TEST(ServerRequestParsingTest, ReadHeadersRegexComplexity) {
// A certain header line causes an exception if the header property is parsed
// naively with a single regex. This occurs with libc++ but not libstdc++.
const std::string req =
test_raw_request(
"GET /hi HTTP/1.1\r\n"
" : "
" ";
" "
);
}

ASSERT_TRUE(send_request(client_read_timeout_sec, req));
svr.stop();
t.join();
EXPECT_TRUE(listen_thread_ok);
TEST(ServerRequestParsingTest, ReadHeadersRegexComplexity2) {
// A certain header line causes an exception if the header property *name* is
// parsed with a regular expression starting with "(.+?):" - this is a non-
// greedy matcher and requires backtracking when there are a lot of ":"
// characters.
// This occurs with libc++ but not libstdc++.
test_raw_request(
"GET /hi HTTP/1.1\r\n"
":-:::::::::::::::::::::::::::-::::::::::::::::::::::::@-&&&&&&&&&&&"
"--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&"
"&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-:::::"
"::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-::::::::::::::::::::::::"
":::::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-:::::::::::::::::::::"
"::::::::-:::::::::::::::::@-&&&&&&&--:::::::-::::::::::::::::::::::"
":::::::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-:::::::::::::::::::"
"::::::::::-:::::::::::::::::@-&&&&&::::::::::::-:::::::::::::::::@-"
"&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-::::::::::::::::"
":@-&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::"
"::::@-&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-::::::@-&&"
"&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@"
"::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&&&&"
"--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&"
"&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&"
"&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@-&&"
"&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::::@"
"-&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::::"
"::@-&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-::::::::::::"
":::::@-&&&&&&&&&&&::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-::::::"
":::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-:::"
"::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&&&&--:::::::-"
":::::::::::::::::::::::::::::-:::::::::::::::::@-&&&&&&&&&&&---&&:&"
"&&.0------------:-:::::::::::::::::::::::::::::-:::::::::::::::::@-"
"&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-::::::::::::::::"
":@-&&&&&&&&&&&--:::::::-:::::::::::::::::::::::::::::-:::::::::::::"
"::::@-&&&&&&&&&&&---&&:&&&.0------------O--------\rH PUTHTTP/1.1\r\n"
"&&&%%%");
}

TEST(ServerStopTest, StopServerWithChunkedTransmission) {
Expand Down