diff options
| -rw-r--r-- | ssh-agent-filter.C | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/ssh-agent-filter.C b/ssh-agent-filter.C index 3307de8..36677f9 100644 --- a/ssh-agent-filter.C +++ b/ssh-agent-filter.C @@ -112,6 +112,17 @@ string base64_encode (string const & s) { return {reinterpret_cast<char const *>(b64), len}; } +void cloexec (int fd) { + if (fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC)) { + perror("fcntl"); + exit(EX_UNAVAILABLE); + } +} + +void arm(std::ios & stream) { + stream.exceptions(stream.badbit | stream.failbit); +} + int make_upstream_agent_conn () { char const * path; int sock; @@ -126,10 +137,7 @@ int make_upstream_agent_conn () { perror("socket"); exit(EX_UNAVAILABLE); } - if (fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC)) { - perror("fcntl"); - exit(EX_UNAVAILABLE); - } + cloexec(sock); addr.sun_family = AF_UNIX; @@ -156,10 +164,7 @@ int make_listen_sock () { perror("socket"); exit(EX_UNAVAILABLE); } - if (fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC)) { - perror("fcntl"); - exit(EX_UNAVAILABLE); - } + cloexec(sock); addr.sun_family = AF_UNIX; @@ -225,12 +230,12 @@ void parse_cmdline (int const argc, char const * const * const argv) { void setup_filters () { io::stream<io::file_descriptor> agent{make_upstream_agent_conn(), io::close_handle}; - agent.exceptions(std::ios::badbit | std::ios::failbit); + arm(agent); agent << rfc4251string{string{SSH2_AGENTC_REQUEST_IDENTITIES}}; rfc4251string answer{agent}; io::stream<io::array_source> answer_iss{answer.data(), answer.size()}; - answer_iss.exceptions(std::ios::badbit | std::ios::failbit); + arm(answer_iss); rfc4251byte resp_code{answer_iss}; if (resp_code != SSH2_AGENT_IDENTITIES_ANSWER) throw runtime_error{"unexpected answer from ssh-agent"}; @@ -314,7 +319,7 @@ bool confirm (string const & question) { bool dissect_auth_data_ssh (rfc4251string const & data, string & request_description) try { io::stream<io::array_source> datastream{data.data(), data.size()}; - datastream.exceptions(std::ios::badbit | std::ios::failbit); + arm(datastream); // Format specified in RFC 4252 Section 7 rfc4251string session_identifier{datastream}; @@ -337,20 +342,20 @@ rfc4251string handle_request (rfc4251string const & r) { io::stream<io::array_source> request{r.data(), r.size()}; rfc4251string ret; io::stream<io::back_insert_device<vector<char>>> answer{ret.value}; - request.exceptions(std::ios::badbit | std::ios::failbit); - answer.exceptions(std::ios::badbit | std::ios::failbit); + arm(request); + arm(answer); rfc4251byte request_code{request}; switch (request_code) { case SSH2_AGENTC_REQUEST_IDENTITIES: { io::stream<io::file_descriptor> agent{make_upstream_agent_conn(), io::close_handle}; - agent.exceptions(std::ios::badbit | std::ios::failbit); + arm(agent); agent << rfc4251string{string{SSH2_AGENTC_REQUEST_IDENTITIES}}; // temp to test key filtering when signing //return rfc4251string{agent}; rfc4251string agent_answer{agent}; io::stream<io::array_source> agent_answer_iss{agent_answer.data(), agent_answer.size()}; - agent_answer_iss.exceptions(std::ios::badbit | std::ios::failbit); + arm(agent_answer_iss); rfc4251byte answer_code{agent_answer_iss}; rfc4251uint32 keycount{agent_answer_iss}; if (answer_code != SSH2_AGENT_IDENTITIES_ANSWER) @@ -397,7 +402,7 @@ rfc4251string handle_request (rfc4251string const & r) { if (allow) { io::stream<io::file_descriptor> agent{make_upstream_agent_conn(), io::close_handle}; - agent.exceptions(std::ios::badbit | std::ios::failbit); + arm(agent); rfc4251string agent_answer; agent << r; @@ -438,7 +443,7 @@ rfc4251string handle_request (rfc4251string const & r) { void handle_client (int const sock) try { io::stream<io::file_descriptor> client{sock, io::close_handle}; - client.exceptions(std::ios::badbit | std::ios::failbit); + arm(client); for (;;) client << handle_request(rfc4251string{client}) << flush; |