3 files changed, 208 insertions, 0 deletions

diff --git a/include/opkele/util.h b/include/opkele/util.h
index edc1859..085c9e6 100644
--- a/include/opkele/util.h
+++ b/include/opkele/util.h
@@ -126,6 +126,16 @@ namespace opkele {
          * @param rv container for decoded binary
          */
         void decode_base64(const string& data,vector<unsigned char>& rv);
+
+        /**
+         * Normalize http(s) URI according to RFC3986, section 6. URI is
+         * expected to have scheme: in front of it.
+         * @param uri URI
+         * @return normalized URI
+         * @throw not_implemented in case of non-httpi(s) URI
+         * @throw bad_input in case of malformed URI
+         */
+        string rfc_3986_normalize_uri(const string& uri);
     }
 
 }
diff --git a/lib/util.cc b/lib/util.cc
index 26be66a..eacf6d7 100644
--- a/lib/util.cc
+++ b/lib/util.cc
@@ -1,8 +1,10 @@
 #include <errno.h>
 #include <cassert>
+#include <cctype>
 #include <cstring>
 #include <vector>
 #include <string>
+#include <stack>
 #include <openssl/bio.h>
 #include <openssl/evp.h>
 #include <curl/curl.h>
@@ -159,6 +161,135 @@ namespace opkele {
             return rv;
         }
 
+        /*
+         * Normalize URL according to the rules, described in rfc 3986, section 6
+         *
+         * - uppercase hext triplets (e.g. %ab -> %AB)
+         * - lowercase scheme and host
+         * - decode %-encoded characters, specified as unreserved in rfc 3986, section 2.3,
+         *   that is - [:alpha:][:digit:]._~-
+         * - remove dot segments
+         * - remove empty and default ports
+         * - if there's no path component, add '/'
+         */
+         string rfc_3986_normalize_uri(const string& uri) {
+             string rv;
+             string::size_type colon = uri.find(':');
+             if(colon==string::npos)
+                 throw bad_input(OPKELE_CP_ "No scheme specified in URI");
+             transform(
+                     uri.begin(), uri.begin()+colon+1,
+                     back_inserter(rv), ::tolower );
+             bool s;
+             if(rv=="http:")
+                 s = false;
+             else if(rv=="https:")
+                 s = true;
+             else
+                 throw not_implemented(OPKELE_CP_ "Only http(s) URIs can be normalized here");
+             string::size_type ul = uri.length();
+             if(ul <= (colon+3))
+                 throw bad_input(OPKELE_CP_ "Unexpected end of URI being normalized encountered");
+             if(uri[colon+1]!='/' || uri[colon+2]!='/')
+                 throw bad_input(OPKELE_CP_ "Unexpected input in URI being normalized after scheme component");
+             rv += "//";
+             string::size_type interesting = uri.find_first_of(":/#?",colon+3);
+             if(interesting==string::npos) {
+                 transform(
+                         uri.begin()+colon+3,uri.end(),
+                         back_inserter(rv), ::tolower );
+                 rv += '/'; return rv;
+             }
+             transform(
+                     uri.begin()+colon+3,uri.begin()+interesting,
+                     back_inserter(rv), ::tolower );
+             bool qf = false;
+             char ic = uri[interesting];
+             if(ic==':') {
+                 string::size_type ni = uri.find_first_of("/#?%",interesting+1);
+                 const char *nptr = uri.data()+interesting+1;
+                 char *eptr = 0;
+                 long port = strtol(nptr,&eptr,10);
+                 if( (port>0) && (port<65535) && port!=(s?443:80) ) {
+                     char tmp[6];
+                     snprintf(tmp,sizeof(tmp),"%d",port);
+                     rv += ':'; rv += tmp;
+                 }
+                 if(ni==string::npos) {
+                     rv += '/'; return rv;
+                 }
+                 interesting = ni;
+             }else if(ic!='/') {
+                 rv += '/'; rv += ic;
+                 qf = true;
+                 ++interesting;
+             }
+             string::size_type n = interesting;
+             char tmp[3] = { 0,0,0 };
+             stack<string::size_type> psegs; psegs.push(rv.length());
+             string pseg;
+             for(;n<ul;) {
+                 string::size_type unsafe = uri.find_first_of(qf?"%":"%/?#",n);
+                 if(unsafe==string::npos) {
+                     pseg.append(uri,n,ul-n-1); n = ul-1;
+                 }else{
+                     pseg.append(uri,n,unsafe-n);
+                     n = unsafe;
+                 }
+                 char c = uri[n++];
+                 if(c=='%') {
+                     if((n+1)>=ul)
+                         throw bad_input(OPKELE_CP_ "Unexpected end of URI encountered while parsing percent-encoded character");
+                     tmp[0] = uri[n++];
+                     tmp[1] = uri[n++];
+                     if(!( isxdigit(tmp[0]) && isxdigit(tmp[1]) ))
+                         throw bad_input(OPKELE_CP_ "Invalid percent-encoded character in URI being normalized");
+                     int cc = strtol(tmp,0,16);
+                     if( isalpha(cc) || isdigit(cc) || strchr("._~-",cc) )
+                         pseg += cc;
+                     else{
+                         pseg += '%';
+                         pseg += toupper(tmp[0]); pseg += toupper(tmp[1]);
+                     }
+                 }else if(qf) {
+                     rv += pseg; rv += c;
+                     pseg.clear();
+                 }else if(n>=ul || strchr("?/#",c)) {
+                     if(pseg.empty() || pseg==".") {
+                     }else if(pseg=="..") {
+                         if(psegs.size()>1) {
+                             rv.resize(psegs.top()); psegs.pop();
+                         }
+                     }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()) {
+                 rv += '/'; rv += pseg;
+             }
+             return rv;
+         }
+
     }
 
 }
diff --git a/test/test.cc b/test/test.cc
index f92284c..1a012b5 100644
--- a/test/test.cc
+++ b/test/test.cc
@@ -3,6 +3,7 @@
 using namespace std;
 #include <opkele/exception.h>
 #include <opkele/consumer.h>
+#include <opkele/util.h>
 
 #include "config.h"
 
@@ -59,8 +60,74 @@ void test_retrieve_links() {
     test_retrieve_links("2rels.html",true,"http://www.klever.net/openid.server","http://www.klever.net/openid.server");
 }
 
+void test_rfc_3986_normalize_uri(const string &ouri,bool success,const string& nuri="") {
+    try {
+        string n = opkele::util::rfc_3986_normalize_uri(ouri);
+        if(!success)
+            throw failed_test(OPKELE_CP_ "Normalized URI when it shouldn't");
+        if(n!=nuri)
+            throw failed_test(OPKELE_CP_ "rfc_3986_test_failed for '"+ouri+"' failed, expected '"+nuri+"', got '"+n+"'");
+    }catch(opkele::bad_input& obi) {
+        if(success)
+            throw failed_test(OPKELE_CP_ "Test '"+ouri+"' failed due to 'bad_input'["+obi.what()+"]");
+    }catch(opkele::not_implemented& oni) {
+        if(success)
+            throw failed_test(OPKELE_CP_ "Test '"+ouri+"' failed due to 'not_implemented'["+oni.what()+"]");
+    }
+}
+
+void test_rfc_3986_normalize_uri() {
+    test_rfc_3986_normalize_uri(
+            "invalid", false );
+    test_rfc_3986_normalize_uri(
+            "ftp://hacker.klever.net/", false );
+    test_rfc_3986_normalize_uri(
+            "http://", false );
+    test_rfc_3986_normalize_uri(
+            "http:/hacker.klever.net/", false );
+    test_rfc_3986_normalize_uri(
+            "hTTp://hacker.klever.net#uh?oh", true, "http://hacker.klever.net/#uh?oh" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net?uh#oh", true, "http://hacker.klever.net/?uh#oh" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net:80/", true, "http://hacker.klever.net/" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net:80?uh", true, "http://hacker.klever.net/?uh" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net:80#uh", true, "http://hacker.klever.net/#uh" );
+    test_rfc_3986_normalize_uri(
+            "https://hacker.klever.net:443", true, "https://hacker.klever.net/" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net:?oh", true, "http://hacker.klever.net/?oh" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah%2E", true, "http://hacker.klever.net/ah." );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%2E/", true, "http://hacker.klever.net/ah/" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%2b/", true, "http://hacker.klever.net/ah/%2B/" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/./oh?eh", true, "http://hacker.klever.net/ah/oh?eh" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/../oh?", true, "http://hacker.klever.net/oh?" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah//oh?", true, "http://hacker.klever.net/ah/oh?" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/?", true, "http://hacker.klever.net/ah/?" );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%", false );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%a", false );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%zx", false );
+    test_rfc_3986_normalize_uri(
+            "http://hacker.klever.net/ah/%5x", false );
+    test_rfc_3986_normalize_uri(
+            "Http://Hacker.Klever.Net:", true, "http://hacker.klever.net/" );
+}
+
 int main() {
     try {
+        test_rfc_3986_normalize_uri();
         test_retrieve_links();
     }catch(failed_test& ft) {
         cerr << "Test failed: " << ft.what() << endl;