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1 files changed, 311 insertions, 0 deletions
diff --git a/lib/basic_rp.cc b/lib/basic_rp.cc
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--- a/dev/null
+++ b/lib/basic_rp.cc
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+#include <openssl/sha.h>
+#include <openssl/hmac.h>
+#include <opkele/basic_rp.h>
+#include <opkele/exception.h>
+#include <opkele/uris.h>
+#include <opkele/data.h>
+#include <opkele/util.h>
+#include <opkele/curl.h>
+
+namespace opkele {
+
+ static void dh_get_secret(
+ secret_t& secret, const basic_openid_message& om,
+ const char *exp_assoc, const char *exp_sess,
+ util::dh_t& dh,
+ size_t d_len, unsigned char *(*d_fun)(const unsigned char*,size_t,unsigned char*) ) try {
+ if(om.get_field("assoc_type")!=exp_assoc || om.get_field("session_type")!=exp_sess)
+ throw bad_input(OPKELE_CP_ "Unexpected associate response");
+ util::bignum_t s_pub = util::base64_to_bignum(om.get_field("dh_server_public"));
+ vector<unsigned char> ck(DH_size(dh)+1);
+ unsigned char *ckptr = &(ck.front())+1;
+ int cklen = DH_compute_key(ckptr,s_pub,dh);
+ if(cklen<0)
+ throw exception_openssl(OPKELE_CP_ "failed to DH_compute_key()");
+ if(cklen && (*ckptr)&0x80) {
+ (*(--ckptr))=0; ++cklen; }
+ unsigned char key_digest[d_len];
+ secret.enxor_from_base64((*d_fun)(ckptr,cklen,key_digest),om.get_field("enc_mac_key"));
+ }catch(opkele::failed_lookup& ofl) {
+ throw bad_input(OPKELE_CP_ "Incoherent response from OP");
+ } OPKELE_RETHROW
+
+ static void direct_request(basic_openid_message& oum,const basic_openid_message& inm,const string& OP) {
+ util::curl_pick_t curl = util::curl_pick_t::easy_init();
+ if(!curl)
+ throw exception_curl(OPKELE_CP_ "failed to initialize curl");
+ string request = inm.query_string();
+ CURLcode r;
+ (r=curl.misc_sets())
+ || (r=curl.easy_setopt(CURLOPT_URL,OP.c_str()))
+ || (r=curl.easy_setopt(CURLOPT_POST,1))
+ || (r=curl.easy_setopt(CURLOPT_POSTFIELDS,request.data()))
+ || (r=curl.easy_setopt(CURLOPT_POSTFIELDSIZE,request.length()))
+ || (r=curl.set_write());
+ if(r)
+ throw exception_curl(OPKELE_CP_ "failed to set curly options",r);
+ if( (r=curl.easy_perform()) )
+ throw exception_curl(OPKELE_CP_ "failed to perform curly request",r);
+ oum.from_keyvalues(curl.response);
+ }
+
+
+ assoc_t basic_RP::associate(const string& OP) {
+ util::dh_t dh = DH_new();
+ if(!dh)
+ throw exception_openssl(OPKELE_CP_ "failed to DH_new()");
+ dh->p = util::dec_to_bignum(data::_default_p);
+ dh->g = util::dec_to_bignum(data::_default_g);
+ if(!DH_generate_key(dh))
+ throw exception_openssl(OPKELE_CP_ "failed to DH_generate_key()");
+ openid_message_t req;
+ req.set_field("ns",OIURI_OPENID20);
+ req.set_field("mode","associate");
+ req.set_field("dh_modulus",util::bignum_to_base64(dh->p));
+ req.set_field("dh_gen",util::bignum_to_base64(dh->g));
+ req.set_field("dh_consumer_public",util::bignum_to_base64(dh->pub_key));
+ openid_message_t res;
+ req.set_field("assoc_type","HMAC-SHA256");
+ req.set_field("session_type","DH-SHA256");
+ secret_t secret;
+ int expires_in;
+ try {
+ direct_request(res,req,OP);
+ dh_get_secret( secret, res,
+ "HMAC-SHA256", "DH-SHA256",
+ dh, SHA256_DIGEST_LENGTH, SHA256 );
+ expires_in = util::string_to_long(res.get_field("expires_in"));
+ }catch(exception& e) {
+ try {
+ req.set_field("assoc_type","HMAC-SHA1");
+ req.set_field("session_type","DH-SHA1");
+ direct_request(res,req,OP);
+ dh_get_secret( secret, res,
+ "HMAC-SHA1", "DH-SHA1",
+ dh, SHA_DIGEST_LENGTH, SHA1 );
+ expires_in = util::string_to_long(res.get_field("expires_in"));
+ }catch(bad_input& e) {
+ throw dumb_RP(OPKELE_CP_ "OP failed to supply an association");
+ }
+ }
+ return store_assoc(
+ OP, res.get_field("assoc_handle"),
+ res.get_field("assoc_type"), secret,
+ expires_in );
+ }
+
+ basic_openid_message& basic_RP::checkid_(
+ basic_openid_message& rv,
+ mode_t mode,
+ const string& return_to,const string& realm,
+ extension_t *ext) {
+ rv.reset_fields();
+ rv.set_field("ns",OIURI_OPENID20);
+ if(mode==mode_checkid_immediate)
+ rv.set_field("mode","checkid_immediate");
+ else if(mode==mode_checkid_setup)
+ rv.set_field("mode","checkid_setup");
+ else
+ throw bad_input(OPKELE_CP_ "unknown checkid_* mode");
+ if(realm.empty() && return_to.empty())
+ throw bad_input(OPKELE_CP_ "At least one of realm and return_to must be non-empty");
+ if(!realm.empty()) {
+ rv.set_field("realm",realm);
+ rv.set_field("trust_root",realm);
+ }
+ if(!return_to.empty())
+ rv.set_field("return_to",return_to);
+ const openid_endpoint_t& ep = get_endpoint();
+ rv.set_field("claimed_id",ep.claimed_id);
+ rv.set_field("identity",ep.local_id);
+ try {
+ rv.set_field("assoc_handle",find_assoc(ep.uri)->handle());
+ }catch(dumb_RP& drp) {
+ }catch(failed_lookup& fl) {
+ try {
+ rv.set_field("assoc_handle",associate(ep.uri)->handle());
+ }catch(dumb_RP& drp) { }
+ } OPKELE_RETHROW
+ if(ext) ext->checkid_hook(rv);
+ return rv;
+ }
+
+ class signed_part_message_proxy : public basic_openid_message {
+ public:
+ const basic_openid_message& x;
+ set<string> signeds;
+
+ signed_part_message_proxy(const basic_openid_message& xx) : x(xx) {
+ const string& slist = x.get_field("signed");
+ string::size_type p = 0;
+ while(true) {
+ string::size_type co = slist.find(',',p);
+ string f = (co==string::npos)
+ ?slist.substr(p):slist.substr(p,co-p);
+ signeds.insert(f);
+ if(co==string::npos) break;
+ p = co+1;
+ }
+ }
+
+ bool has_field(const string& n) const {
+ return signeds.find(n)!=signeds.end() && x.has_field(n); }
+ const string& get_field(const string& n) const {
+ if(signeds.find(n)==signeds.end())
+ throw failed_lookup(OPKELE_CP_ "The field isn't known to be signed");
+ return x.get_field(n); }
+
+ fields_iterator fields_begin() const {
+ return signeds.begin(); }
+ fields_iterator fields_end() const {
+ return signeds.end(); }
+ };
+
+ static void parse_query(const string& u,string::size_type q,
+ map<string,string>& p) {
+ if(q==string::npos)
+ return;
+ assert(u[q]=='?');
+ ++q;
+ string::size_type l = u.size();
+ while(q<l) {
+ string::size_type eq = u.find('=',q);
+ string::size_type am = u.find('&',q);
+ if(am==string::npos) {
+ if(eq==string::npos) {
+ p[""] = u.substr(q);
+ }else{
+ p[u.substr(q,eq-q)] = u.substr(eq+1);
+ }
+ break;
+ }else{
+ if(eq==string::npos || eq>am) {
+ p[""] = u.substr(q,eq-q);
+ }else{
+ p[u.substr(q,eq-q)] = u.substr(eq+1,am-eq-1);
+ }
+ q = ++am;
+ }
+ }
+ }
+
+ void basic_RP::id_res(const basic_openid_message& om,extension_t *ext) {
+ bool o2 = om.has_field("ns")
+ && om.get_field("ns")==OIURI_OPENID20;
+ if( (!o2) && om.has_field("user_setup_url"))
+ throw id_res_setup(OPKELE_CP_ "assertion failed, setup url provided",
+ om.get_field("user_setup_url"));
+ string m = om.get_field("mode");
+ if(o2 && m=="setup_needed")
+ throw id_res_setup(OPKELE_CP_ "setup needed, no setup url provided");
+ if(m=="cancel")
+ throw id_res_cancel(OPKELE_CP_ "authentication cancelled");
+ bool go_dumb=false;
+ try {
+ string OP = o2
+ ?om.get_field("op_endpoint")
+ :get_endpoint().uri;
+ assoc_t assoc = retrieve_assoc(
+ OP,om.get_field("assoc_handle"));
+ if(om.get_field("sig")!=util::base64_signature(assoc,om))
+ throw id_res_mismatch(OPKELE_CP_ "signature mismatch");
+ }catch(dumb_RP& drp) {
+ go_dumb=true;
+ }catch(failed_lookup& e) {
+ go_dumb=true;
+ } OPKELE_RETHROW
+ if(go_dumb) {
+ try {
+ string OP = o2
+ ?om.get_field("op_endpoint")
+ :get_endpoint().uri;
+ check_authentication(OP,om);
+ }catch(failed_check_authentication& fca) {
+ throw id_res_failed(OPKELE_CP_ "failed to check_authentication()");
+ } OPKELE_RETHROW
+ }
+ signed_part_message_proxy signeds(om);
+ if(o2) {
+ check_nonce(om.get_field("op_endpoint"),
+ om.get_field("response_nonce"));
+ static const char *mustsign[] = {
+ "op_endpoint", "return_to", "response_nonce", "assoc_handle",
+ "claimed_id", "identity" };
+ for(int ms=0;ms<(sizeof(mustsign)/sizeof(*mustsign));++ms) {
+ if(om.has_field(mustsign[ms]) && !signeds.has_field(mustsign[ms]))
+ throw bad_input(OPKELE_CP_ string("Field '")+mustsign[ms]+"' is not signed against the specs");
+ }
+ if( (
+ (om.has_field("claimed_id")?1:0)
+ ^
+ (om.has_field("identity")?1:0)
+ )&1 )
+ throw bad_input(OPKELE_CP_ "claimed_id and identity must be either both present or both absent");
+
+ string turl = util::rfc_3986_normalize_uri(get_this_url());
+ util::strip_uri_fragment_part(turl);
+ string rurl = util::rfc_3986_normalize_uri(om.get_field("return_to"));
+ util::strip_uri_fragment_part(rurl);
+ string::size_type
+ tq = turl.find('?'), rq = rurl.find('?');
+ if(
+ ((tq==string::npos)?turl:turl.substr(0,tq))
+ !=
+ ((rq==string::npos)?rurl:rurl.substr(0,rq))
+ )
+ throw id_res_bad_return_to(OPKELE_CP_ "return_to url doesn't match request url");
+ map<string,string> tp; parse_query(turl,tq,tp);
+ map<string,string> rp; parse_query(rurl,rq,rp);
+ for(map<string,string>::const_iterator rpi=rp.begin();rpi!=rp.end();++rpi) {
+ map<string,string>::const_iterator tpi = tp.find(rpi->first);
+ if(tpi==tp.end())
+ throw id_res_bad_return_to(OPKELE_CP_ string("Parameter '")+rpi->first+"' from return_to is missing from the request");
+ if(tpi->second!=rpi->second)
+ throw id_res_bad_return_to(OPKELE_CP_ string("Parameter '")+rpi->first+"' from return_to doesn't matche the request");
+ }
+
+ if(om.has_field("claimed_id")) {
+ verify_OP(
+ om.get_field("op_endpoint"),
+ om.get_field("claimed_id"),
+ om.get_field("identity") );
+ }
+
+ }
+ if(ext) ext->id_res_hook(om,signeds);
+ }
+
+ class check_auth_message_proxy : public basic_openid_message {
+ public:
+ const basic_openid_message& x;
+
+ check_auth_message_proxy(const basic_openid_message& xx) : x(xx) { }
+
+ bool has_field(const string& n) const { return x.has_field(n); }
+ const string& get_field(const string& n) const {
+ static const string checkauthmode="check_authentication";
+ return (n=="mode")?checkauthmode:x.get_field(n); }
+ bool has_ns(const string& uri) const {return x.has_ns(uri); }
+ string get_ns(const string& uri) const { return x.get_ns(uri); }
+ fields_iterator fields_begin() const {
+ return x.fields_begin(); }
+ fields_iterator fields_end() const {
+ return x.fields_end(); }
+ };
+
+ void basic_RP::check_authentication(const string& OP,
+ const basic_openid_message& om){
+ openid_message_t res;
+ direct_request(res,check_auth_message_proxy(om),OP);
+ if(res.has_field("is_valid")) {
+ if(res.get_field("is_valid")=="true") {
+ if(res.has_field("invalidate_handle"))
+ invalidate_assoc(OP,res.get_field("invalidate_handle"));
+ return;
+ }
+ }
+ throw failed_check_authentication(
+ OPKELE_CP_ "failed to verify response");
+ }
+
+}