diff options
| -rw-r--r-- | rfc4251.h | 21 | ||||
| -rw-r--r-- | ssh-agent-filter.C | 67 |
2 files changed, 47 insertions, 41 deletions
@@ -45,6 +45,7 @@ struct rfc4251byte { rfc4251byte () = default; explicit rfc4251byte (uint8_t v) : value(v) {} + inline explicit rfc4251byte (std::istream &); operator uint8_t () const { return value; } }; @@ -57,6 +58,9 @@ inline std::ostream & operator<< (std::ostream & os, rfc4251byte const & x) { return os.write(x.buf, sizeof(x.buf)); } +inline rfc4251byte::rfc4251byte (std::istream & is) { + is >> *this; +} struct rfc4251bool { union { @@ -66,6 +70,7 @@ struct rfc4251bool { rfc4251bool () = default; explicit rfc4251bool (uint8_t v) : value(v) {} + inline explicit rfc4251bool (std::istream &); operator uint8_t () const { return value; } }; @@ -78,6 +83,9 @@ inline std::ostream & operator<< (std::ostream & os, rfc4251bool const & x) { return os.write(x.buf, sizeof(x.buf)); } +inline rfc4251bool::rfc4251bool (std::istream & is) { + is >> *this; +} struct rfc4251uint32 { union { @@ -87,6 +95,7 @@ struct rfc4251uint32 { rfc4251uint32 () = default; explicit rfc4251uint32 (uint32_t v) { value = htonl(v); } + inline explicit rfc4251uint32 (std::istream &); operator uint32_t () const { return ntohl(value); } }; @@ -99,6 +108,9 @@ inline std::ostream & operator<< (std::ostream & os, rfc4251uint32 const & x) { return os.write(x.buf, sizeof(x.buf)); } +inline rfc4251uint32::rfc4251uint32 (std::istream & is) { + is >> *this; +} struct rfc4251uint64 { union { @@ -108,6 +120,7 @@ struct rfc4251uint64 { rfc4251uint64 () = default; inline explicit rfc4251uint64 (uint64_t v); + inline explicit rfc4251uint64 (std::istream &); inline explicit operator uint64_t () const; }; @@ -136,6 +149,9 @@ inline std::ostream & operator<< (std::ostream & os, rfc4251uint64 const & x) { return os.write(x.buf, sizeof(x.buf)); } +inline rfc4251uint64::rfc4251uint64 (std::istream & is) { + is >> *this; +} struct rfc4251string : boost::totally_ordered<rfc4251string> { std::vector<char> value; @@ -147,6 +163,7 @@ struct rfc4251string : boost::totally_ordered<rfc4251string> { explicit rfc4251string (std::vector<std::string> const &); explicit rfc4251string (mpz_srcptr); explicit rfc4251string (mpz_class const & x) : rfc4251string{x.get_mpz_t()} {} + inline explicit rfc4251string (std::istream &); operator std::string () const { return {value.begin(), value.end()}; } operator std::vector<std::string> () const; @@ -213,6 +230,10 @@ inline std::ostream & operator<< (std::ostream & os, rfc4251string const & s) { return os; } +inline rfc4251string::rfc4251string (std::istream & is) { + is >> *this; +} + inline bool operator== (rfc4251string const & l, rfc4251string const & r) { return l.value == r.value; } diff --git a/ssh-agent-filter.C b/ssh-agent-filter.C index 46d9f94..17090e9 100644 --- a/ssh-agent-filter.C +++ b/ssh-agent-filter.C @@ -209,20 +209,15 @@ void setup_filters () { agent.exceptions(std::ios::badbit | std::ios::failbit); agent << rfc4251string{std::string{SSH2_AGENTC_REQUEST_IDENTITIES}}; - rfc4251string answer; - agent >> answer; - std::istringstream answer_iss{answer}; + std::istringstream answer_iss{rfc4251string{agent}}; answer_iss.exceptions(std::ios::badbit | std::ios::failbit); - rfc4251byte resp_code; - answer_iss >> resp_code; + rfc4251byte resp_code{answer_iss}; if (resp_code != SSH2_AGENT_IDENTITIES_ANSWER) throw std::runtime_error{"unexpected answer from ssh-agent"}; - rfc4251uint32 keycount; - answer_iss >> keycount; + rfc4251uint32 keycount{answer_iss}; for (uint32_t i = keycount; i; --i) { - rfc4251string key; - rfc4251string comment; - answer_iss >> key >> comment; + rfc4251string key{answer_iss}; + rfc4251string comment{answer_iss}; auto b64 = base64_encode(key); if (debug) std::clog << b64 << std::endl; @@ -302,14 +297,14 @@ bool dissect_auth_data_ssh (rfc4251string const & data, std::string & request_de datastream.exceptions(std::ios::badbit | std::ios::failbit); // Format specified in RFC 4252 Section 7 - rfc4251string session_identifier; datastream >> session_identifier; - rfc4251byte requesttype; datastream >> requesttype; - rfc4251string username; datastream >> username; - rfc4251string servicename; datastream >> servicename; - rfc4251string publickeystring; datastream >> publickeystring; - rfc4251bool shouldbetrue; datastream >> shouldbetrue; - rfc4251string publickeyalgorithm; datastream >> publickeyalgorithm; - rfc4251string publickey; datastream >> publickey; + rfc4251string session_identifier{datastream}; + rfc4251byte requesttype{datastream}; + rfc4251string username{datastream}; + rfc4251string servicename{datastream}; + rfc4251string publickeystring{datastream}; + rfc4251bool shouldbetrue{datastream}; + rfc4251string publickeyalgorithm{datastream}; + rfc4251string publickey{datastream}; request_description = "The request is for an ssh connection as user '" + std::string{username} + "' with service name '" + std::string{servicename} + "'."; @@ -323,31 +318,26 @@ rfc4251string handle_request (rfc4251string const & r) { std::ostringstream answer; request.exceptions(std::ios::badbit | std::ios::failbit); answer.exceptions(std::ios::badbit | std::ios::failbit); - rfc4251byte request_code; - request >> request_code; + rfc4251byte request_code{request}; switch (request_code) { case SSH2_AGENTC_REQUEST_IDENTITIES: { io::stream_buffer<io::file_descriptor> agent_filebuf{make_upstream_agent_conn(), io::close_handle}; std::iostream agent{&agent_filebuf}; agent.exceptions(std::ios::badbit | std::ios::failbit); - rfc4251string agent_answer; agent << rfc4251string{std::string{SSH2_AGENTC_REQUEST_IDENTITIES}}; - agent >> agent_answer; // temp to test key filtering when signing - //return agent_answer; - std::istringstream agent_answer_iss{agent_answer}; + //return rfc4251string{agent}; + std::istringstream agent_answer_iss{rfc4251string{agent}}; agent_answer_iss.exceptions(std::ios::badbit | std::ios::failbit); - rfc4251byte answer_code; - rfc4251uint32 keycount; - agent_answer_iss >> answer_code >> keycount; + rfc4251byte answer_code{agent_answer_iss}; + rfc4251uint32 keycount{agent_answer_iss}; if (answer_code != SSH2_AGENT_IDENTITIES_ANSWER) throw std::runtime_error{"unexpected answer from ssh-agent"}; std::vector<std::pair<rfc4251string, rfc4251string>> keys; for (uint32_t i = keycount; i; --i) { - rfc4251string key; - rfc4251string comment; - agent_answer_iss >> key >> comment; + rfc4251string key{agent_answer_iss}; + rfc4251string comment{agent_answer_iss}; if (allowed_pubkeys.count(key) or confirmed_pubkeys.count(key)) keys.emplace_back(std::move(key), std::move(comment)); } @@ -358,10 +348,9 @@ rfc4251string handle_request (rfc4251string const & r) { break; case SSH2_AGENTC_SIGN_REQUEST: { - rfc4251string key; - rfc4251string data; - rfc4251uint32 flags; - request >> key >> data >> flags; + rfc4251string key{request}; + rfc4251string data{request}; + rfc4251uint32 flags{request}; bool allow{false}; if (allowed_pubkeys.count(key)) @@ -392,8 +381,7 @@ rfc4251string handle_request (rfc4251string const & r) { rfc4251string agent_answer; agent << r; - agent >> agent_answer; - return agent_answer; + return rfc4251string{agent}; } else answer << rfc4251byte{SSH_AGENT_FAILURE}; } @@ -432,11 +420,8 @@ void handle_client (int const sock) try { std::iostream client{&client_filebuf}; client.exceptions(std::ios::badbit | std::ios::failbit); - for (;;) { - rfc4251string request; - client >> request; - client << handle_request(request) << std::flush; - } + for (;;) + client << handle_request(rfc4251string{client}) << std::flush; } catch (...) { } |