moved uri matching into separate procedure

Signed-off-by: Michael Krelin <hacker@klever.net>

2 files changed, 33 insertions, 32 deletions

diff --git a/lib/basic_op.cc b/lib/basic_op.cc
index f7573aa..11ffb48 100644
--- a/lib/basic_op.cc
+++ b/lib/basic_op.cc
@@ -1,62 +1,59 @@
 #include <time.h>
 #include <cassert>
-#include <algorithm>
 #include <openssl/sha.h>
 #include <openssl/hmac.h>
 #include <opkele/data.h>
 #include <opkele/basic_op.h>
 #include <opkele/exception.h>
 #include <opkele/util.h>
 #include <opkele/uris.h>
 
 namespace opkele {
-    using std::pair;
-    using std::mismatch;
 
     void basic_op::reset_vars() {
         assoc.reset();
         return_to.clear(); realm.clear();
         claimed_id.clear(); identity.clear();
         invalidate_handle.clear();
     }
 
     bool basic_op::has_return_to() const {
         return !return_to.empty();
     }
     const string& basic_op::get_return_to() const {
         if(return_to.empty())
             throw no_return_to(OPKELE_CP_ "No return_to URL provided with request");
         return return_to;
     }
 
     const string& basic_op::get_realm() const {
         assert(!realm.empty());
         return realm;
     }
 
     bool basic_op::has_identity() const {
         return !identity.empty();
     }
     const string& basic_op::get_claimed_id() const {
         if(claimed_id.empty())
             throw non_identity(OPKELE_CP_ "attempting to retrieve claimed_id of non-identity related request");
         assert(!identity.empty());
         return claimed_id;
     }
     const string& basic_op::get_identity() const {
         if(identity.empty())
             throw non_identity(OPKELE_CP_ "attempting to retrieve identity of non-identity related request");
         assert(!claimed_id.empty());
         return identity;
     }
 
     bool basic_op::is_id_select() const {
         return identity==IDURI_SELECT20;
     }
 
     void basic_op::select_identity(const string& c,const string& i) {
         claimed_id = c; identity = i;
     }
     void basic_op::set_claimed_id(const string& c) {
         claimed_id = c;
     }
@@ -276,81 +273,55 @@ namespace opkele {
         try {
             o2 = (inm.get_field("ns")==OIURI_OPENID20);
         }catch(failed_lookup&) { o2 = false; }
         string nonce;
         if(o2) {
             try {
                 if(!check_nonce(nonce = inm.get_field("response_nonce")))
                     throw failed_check_authentication(OPKELE_CP_ "Invalid nonce");
             }catch(failed_lookup&) {
                 throw failed_check_authentication(OPKELE_CP_ "No nonce provided with check_authentication request");
             }
         }
         try {
             assoc = retrieve_assoc(inm.get_field("assoc_handle"));
             if(!assoc->stateless())
                 throw failed_check_authentication(OPKELE_CP_ "Will not do check_authentication on a stateful handle");
         }catch(failed_lookup&) {
             throw failed_check_authentication(OPKELE_CP_ "No assoc_handle or invalid assoc_handle specified with check_authentication request");
         }
         static const string idresmode = "id_res";
         try {
             if(util::base64_signature(assoc,util::change_mode_message_proxy(inm,idresmode))!=inm.get_field("sig"))
                 throw failed_check_authentication(OPKELE_CP_ "Signature mismatch");
         }catch(failed_lookup&) {
             throw failed_check_authentication(OPKELE_CP_ "failed to calculate signature");
         }
         oum.set_field("is_valid","true");
         try {
             string h = inm.get_field("invalidate_handle");
             try {
                 assoc_t ih = retrieve_assoc(h);
             }catch(invalid_handle& ih) {
                 oum.set_field("invalidate_handle",h);
             }catch(failed_lookup& ih) {
                 oum.set_field("invalidate_handle",h);
             }
         }catch(failed_lookup&) { }
         if(o2) {
             assert(!nonce.empty());
             invalidate_nonce(nonce);
         }
         return oum;
     }catch(failed_check_authentication& ) {
         oum.set_field("is_valid","false");
         return oum;
     }
 
     void basic_op::verify_return_to() {
-        string nrealm = opkele::util::rfc_3986_normalize_uri(realm);
-        if(nrealm.find('#')!=string::npos)
+        if(realm.find('#')!=string::npos)
             throw opkele::bad_realm(OPKELE_CP_ "authentication realm contains URI fragment");
-        string nrt = opkele::util::rfc_3986_normalize_uri(return_to);
-        string::size_type pr = nrealm.find("://");
-        string::size_type prt = nrt.find("://");
-        assert(!(pr==string::npos || prt==string::npos));
-        pr += sizeof("://")-1;
-        prt += sizeof("://")-1;
-        if(!strncmp(nrealm.c_str()+pr,"*.",2)) {
-            pr = nrealm.find('.',pr);
-            prt = nrt.find('.',prt);
-            assert(pr!=string::npos);
-            if(prt==string::npos)
-                throw bad_return_to(
-                        OPKELE_CP_ "return_to URL doesn't match realm");
-            // TODO: check for overgeneralized realm
-        }
-        string::size_type lr = nrealm.length();
-        string::size_type lrt = nrt.length();
-        if( (lrt-prt) < (lr-pr) )
-            throw bad_return_to(
-                    OPKELE_CP_ "return_to URL doesn't match realm");
-        pair<const char*,const char*> mp = mismatch(
-                nrealm.c_str()+pr,nrealm.c_str()+lr,
-                nrt.c_str()+prt);
-        if( (*(mp.first-1))!='/'
-                && !strchr("/?#",*mp.second) )
-            throw bad_return_to(
-                    OPKELE_CP_ "return_to URL doesn't match realm");
+        if(!util::uri_matches_realm(return_to,realm))
+            throw bad_return_to(OPKELE_CP_ "return_to URL doesn't match realm");
     }
 
 }
diff --git a/lib/util.cc b/lib/util.cc
index b7bc437..b85a377 100644
--- a/lib/util.cc
+++ b/lib/util.cc
@@ -1,55 +1,56 @@
 #include <errno.h>
 #include <cassert>
 #include <cctype>
 #include <cstring>
 #include <vector>
 #include <string>
 #include <stack>
+#include <algorithm>
 #include <openssl/bio.h>
 #include <openssl/evp.h>
 #include <openssl/hmac.h>
 #include <curl/curl.h>
 #include "opkele/util.h"
 #include "opkele/exception.h"
 
 #include <config.h>
 #ifdef HAVE_DEMANGLE
 # include <cxxabi.h>
 #endif
 
 namespace opkele {
     using namespace std;
 
     namespace util {
 
         /*
          * base64
          */
         string encode_base64(const void *data,size_t length) {
             BIO *b64 = 0, *bmem = 0;
             try {
                 b64 = BIO_new(BIO_f_base64());
                 if(!b64)
                     throw exception_openssl(OPKELE_CP_ "failed to BIO_new() base64 encoder");
                 BIO_set_flags(b64,BIO_FLAGS_BASE64_NO_NL);
                 bmem = BIO_new(BIO_s_mem());
                 BIO_set_flags(b64,BIO_CLOSE);
                 if(!bmem)
                     throw exception_openssl(OPKELE_CP_ "failed to BIO_new() memory buffer");
                 BIO_push(b64,bmem);
                 if(((size_t)BIO_write(b64,data,length))!=length)
                     throw exception_openssl(OPKELE_CP_ "failed to BIO_write()");
                 if(BIO_flush(b64)!=1)
                     throw exception_openssl(OPKELE_CP_ "failed to BIO_flush()");
                 char *rvd;
                 long rvl = BIO_get_mem_data(bmem,&rvd);
                 string rv(rvd,rvl);
                 BIO_free_all(b64);
                 return rv;
             }catch(...) {
                 if(b64) BIO_free_all(b64);
                 throw;
             }
         }
 
         void decode_base64(const string& data,vector<unsigned char>& rv) {
@@ -306,96 +307,125 @@ namespace opkele {
                          }
                      }else{
                          psegs.push(rv.length());
                          if(c!='/') {
                              pseg += c;
                              qf = true;
                          }
                          rv += '/'; rv += pseg;
                      }
                      if(c=='/' && (n>=ul || strchr("?#",uri[n])) ) {
                          rv += '/';
                          if(n<ul)
                              qf = true;
                      }else if(strchr("?#",c)) {
                          if(psegs.size()==1 && psegs.top()==rv.length())
                              rv += '/';
                          if(pseg.empty())
                              rv += c;
                          qf = true;
                      }
                      pseg.clear();
                  }else{
                      pseg += c;
                  }
              }
              if(!pseg.empty()) {
                  if(!qf) rv += '/';
                  rv += pseg;
              }
              return rv;
          }
 
         string& strip_uri_fragment_part(string& u) {
             string::size_type q = u.find('?'), f = u.find('#');
             if(q==string::npos) {
                 if(f!=string::npos)
                     u.erase(f);
             }else{
                 if(f!=string::npos) {
                     if(f<q)
                         u.erase(f,q-f);
                     else
                         u.erase(f);
                 }
             }
             return u;
         }
 
+        bool uri_matches_realm(const string& uri,const string& realm) {
+            string nrealm = opkele::util::rfc_3986_normalize_uri(realm);
+            string nu = opkele::util::rfc_3986_normalize_uri(uri);
+            string::size_type pr = nrealm.find("://");
+            string::size_type pu = nu.find("://");
+            assert(!(pr==string::npos || pu==string::npos));
+            pr += sizeof("://")-1;
+            pu += sizeof("://")-1;
+            if(!strncmp(nrealm.c_str()+pr,"*.",2)) {
+                pr = nrealm.find('.',pr);
+                pu = nu.find('.',pu);
+                assert(pr!=string::npos);
+                if(pu==string::npos)
+                    return false;
+                // TODO: check for overgeneralized realm
+            }
+            string::size_type lr = nrealm.length();
+            string::size_type lu = nu.length();
+            if( (lu-pu) < (lr-pr) )
+                return false;
+            pair<const char*,const char*> mp = mismatch(
+                    nrealm.c_str()+pr,nrealm.c_str()+lr,
+                    nu.c_str()+pu);
+            if( (*(mp.first-1))!='/'
+                    && !strchr("/?#",*mp.second) )
+                return false;
+            return true;
+        }
+
         string abi_demangle(const char *mn) {
 #ifndef HAVE_DEMANGLE
             return mn;
 #else /* !HAVE_DEMANGLE */
             int dstat;
             char *demangled = abi::__cxa_demangle(mn,0,0,&dstat);
             if(dstat)
                 return mn;
             string rv = demangled;
             free(demangled);
             return rv;
 #endif /* !HAVE_DEMANGLE */
         }
 
         string base64_signature(const assoc_t& assoc,const basic_openid_message& om) {
             const string& slist = om.get_field("signed");
             string kv;
             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);
                 kv += f;
                 kv += ':';
                 kv += om.get_field(f);
                 kv += '\n';
                 if(co==string::npos) break;
                 p = co+1;
             }
             const secret_t& secret = assoc->secret();
             const EVP_MD *evpmd;
             const string& at = assoc->assoc_type();
             if(at=="HMAC-SHA256")
                 evpmd = EVP_sha256();
             else if(at=="HMAC-SHA1")
                 evpmd = EVP_sha1();
             else
                 throw unsupported(OPKELE_CP_ "unknown association type");
             unsigned int md_len = 0;
             unsigned char *md = HMAC(evpmd,
                     &(secret.front()),secret.size(),
                     (const unsigned char*)kv.data(),kv.length(),
                     0,&md_len);
             return encode_base64(md,md_len);
         }
 
     }