9 files changed, 482 insertions, 9 deletions

diff --git a/include/Makefile.am b/include/Makefile.am
index 0385cfb..23c7e0d 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -10,8 +10,10 @@ nobase_include_HEADERS = \
         opkele/sreg.h \
         opkele/extension_chain.h \
         opkele/xconsumer.h \
-        opkele/xserver.h
+        opkele/xserver.h \
+        opkele/curl.h opkele/expat.h \
+        opkele/openid_service_resolver.h \
+        opkele/uris.h
 EXTRA_DIST = \
         opkele/data.h \
-        opkele/util.h \
-        opkele/curl.h opkele/expat.h
+        opkele/util.h
diff --git a/include/opkele/openid_service_resolver.h b/include/opkele/openid_service_resolver.h
new file mode 100644
index 0000000..64edd28
--- a/dev/null
+++ b/include/opkele/openid_service_resolver.h
@@ -0,0 +1,118 @@
+#ifndef __OPKELE_OPENID_SERVICE_RESOLVER_H
+#define __OPKELE_OPENID_SERVICE_RESOLVER_H
+
+#include <climits>
+#include <string>
+#include <list>
+#include <set>
+#include <map>
+#include <opkele/curl.h>
+#include <opkele/expat.h>
+
+namespace opkele {
+    using std::list;
+    using std::string;
+    using std::set;
+    using std::map;
+
+    struct openid_auth_SEP_t {
+            long priority;
+            set<string> xrd_Type;
+            string xrd_URI;
+            string openid_Delegate;
+
+            openid_auth_SEP_t() : priority(LONG_MAX) { }
+    };
+
+    struct openid_auth_info_t {
+        string canonical_id;
+        openid_auth_SEP_t auth_SEP;
+    };
+
+
+    class openid_service_resolver_t : public util::curl_t, public util::expat_t {
+        public:
+            string xri_proxy;
+
+            openid_service_resolver_t(const string& xp="");
+            ~openid_service_resolver_t() throw() { }
+
+            const openid_auth_info_t& resolve(const string& id);
+
+            enum state_t {
+                state_parse = 0,
+                state_stopping_head, state_stopping_body,
+                state_stopping_size
+            };
+            state_t state;
+
+            struct parser_node_t {
+                string element;
+                string content;
+                typedef map<string,string> attrs_t;
+                attrs_t attrs;
+                bool skip_text, skip_tags;
+                openid_auth_info_t auth_info;
+
+                parser_node_t(const XML_Char *n,const XML_Char **a)
+                    : skip_text(true), skip_tags(true)
+                {
+                    element = n;
+                    for(;*a;a+=2)
+                        attrs[a[0]] = a[1];
+                }
+
+            };
+
+            class parser_tree_t : public list<parser_node_t> {
+                public:
+                    const_reference top() const { return back(); }
+                    reference top()  { return back(); }
+
+                    const_reference parent() const {
+                        const_reverse_iterator rv = rbegin();
+                        return *(++rv); }
+                    reference parent() {
+                        reverse_iterator rv = rbegin();
+                        return *(++rv); }
+
+                    inline void pop() { pop_back(); }
+                    inline void push(const_reference e) { push_back(e); }
+
+                    void push(const XML_Char *n,const XML_Char **a) {
+                        parser_node_t nn(n,a);
+                        if(empty())
+                            nn.skip_text = nn.skip_tags = true;
+                        else{
+                            const_reference t = top();
+                            nn.skip_text = t.skip_text; nn.skip_tags = t.skip_tags;
+                        }
+                        push(nn);
+                    }
+            };
+            parser_tree_t tree;
+
+            void start_element(const XML_Char *n,const XML_Char **a);
+            void end_element(const XML_Char *n);
+            void character_data(const XML_Char *s,int l);
+
+            string xrds_location;
+            openid_auth_SEP_t html_SEP;
+            openid_auth_info_t auth_info;
+
+            void pop_tag();
+
+            size_t write(void *p,size_t s,size_t nm);
+
+            string http_content_type;
+
+            size_t header(void *p,size_t s,size_t nm);
+            
+            bool xri_mode;
+
+            void discover_service(const string& url,bool xri=false);
+    };
+
+}
+
+#endif /* __OPKELE_OPENID_SERVICE_RESOLVER_H */
diff --git a/include/opkele/uris.h b/include/opkele/uris.h
new file mode 100644
index 0000000..9a6a3cd
--- a/dev/null
+++ b/include/opkele/uris.h
@@ -0,0 +1,10 @@
+#ifndef __OPKELE_URIS_H
+#define __OPKELE_URIS_H
+
+#define NSURI_XRDS     "xri://$xrds"
+#define NSURI_XRD      "xri://$xrd*($v*2.0)"
+#define NSURI_OPENID10 "http://openid.net/xmlns/1.0"
+
+#define STURI_OPENID10 "http://openid.net/signon/1.0"
+
+#endif /* __OPKELE_URIS_H */
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 7309353..b278faf 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -24,6 +24,7 @@ libopkele_la_SOURCES = \
                        extension.cc \
                        sreg.cc \
                        extension_chain.cc \
-                       curl.cc expat.cc
+                       curl.cc expat.cc \
+                       openid_service_resolver.cc
 libopkele_la_LDFLAGS = \
         -version-info 2:0:0
diff --git a/lib/openid_service_resolver.cc b/lib/openid_service_resolver.cc
new file mode 100644
index 0000000..5f82955
--- a/dev/null
+++ b/lib/openid_service_resolver.cc
@@ -0,0 +1,294 @@
+#include <cctype>
+#include <opkele/exception.h>
+#include <opkele/util.h>
+#include <opkele/openid_service_resolver.h>
+#include <opkele/uris.h>
+
+#define LOCATION_HEADER "X-XRDS-Location"
+
+namespace opkele {
+    static const char *whitespace = " \t\r\n";
+
+    openid_service_resolver_t::openid_service_resolver_t(const string& xp)
+        : util::curl_t(easy_init()),
+        util::expat_t(0),
+        xri_proxy(xp.empty()?"http://beta.xri.net/":xp)
+    {
+        CURLcode r;
+        (r=misc_sets())
+        || (r=set_write())
+        || (r==set_header())
+        ;
+        if(r)
+            throw opkele::exception_curl(OPKELE_CP_ "failed to set curly options",r);
+    }
+
+    static bool is_element(const XML_Char *n,const char *en) {
+        if(!strcasecmp(n,en)) return true;
+        int nl = strlen(n), enl = strlen(en);
+        if( (nl>=(enl+1)) && n[nl-enl-1]=='\t'
+                && !strcasecmp(&n[nl-enl],en) )
+            return true;
+        return false;
+    }
+    static inline bool is_qelement(const XML_Char *n,const char *qen) {
+        return !strcasecmp(n,qen);
+    }
+    static inline bool is_element(
+            const openid_service_resolver_t::parser_node_t& n,
+            const char *en) {
+        return is_element(n.element.c_str(),en);
+    }
+    static inline bool is_qelement(
+            const openid_service_resolver_t::parser_node_t& n,
+            const char *qen) {
+        return is_qelement(n.element.c_str(),qen);
+    }
+
+    void openid_service_resolver_t::start_element(const XML_Char *n,const XML_Char **a) {
+        if(state!=state_parse) return;
+        tree.push(n,a);
+        parser_node_t& t = tree.top();
+        if(is_element(n,"html") || is_element(n,"head")
+                || is_qelement(n,NSURI_XRDS "\tXRDS")
+                || is_qelement(n,NSURI_XRD "\tXRD") )
+            t.skip_tags = false;
+        else if(is_qelement(n,NSURI_XRD "\tService")
+                || is_qelement(n,NSURI_XRD "\tType")
+                || is_qelement(n,NSURI_XRD "\tURI")
+                || is_qelement(n,NSURI_OPENID10 "\tDelegate")
+                || is_qelement(n,NSURI_XRD "\tCanonicalID") )
+            t.skip_tags = t.skip_text = false;
+        else if(is_element(n,"body"))
+            state = state_stopping_body;
+    }
+    void openid_service_resolver_t::end_element(const XML_Char *n) {
+        if(state!=state_parse) return;
+        assert(tree.top().element == n);
+        pop_tag();
+    }
+    void openid_service_resolver_t::character_data(const XML_Char *s,int l) {
+        if(state!=state_parse) return;
+        if( !( tree.empty() || tree.top().skip_text ) )
+            tree.top().content.append(s,l);
+    }
+
+    static void copy_trim_whitespace(string& to,const string& from) {
+        string::size_type ns0 = from.find_first_not_of(whitespace);
+        if(ns0==string::npos) {
+            to.clear(); return;
+        }
+        string::size_type ns1 = from.find_last_not_of(whitespace);
+        assert(ns1!=string::npos);
+        to.assign(from,ns0,ns1-ns0+1);
+    }
+
+    void openid_service_resolver_t::pop_tag() {
+        assert(!tree.empty());
+        parser_node_t& t = tree.top();
+        if( is_element(t,"meta")
+                && !strcasecmp(t.attrs["http-equiv"].c_str(),LOCATION_HEADER) ) {
+            xrds_location = t.attrs["content"];
+        }else if( is_element(t,"link") ) {
+            parser_node_t::attrs_t::const_iterator ir = t.attrs.find("rel");
+            if(ir!=t.attrs.end()) {
+                const string& rels = ir->second;
+                for(string::size_type ns = rels.find_first_not_of(whitespace);
+                        ns!=string::npos;
+                        ns=rels.find_first_not_of(whitespace,ns)) {
+                    string::size_type s = rels.find_first_of(whitespace,ns);
+                    string rel;
+                    if(s==string::npos) {
+                        rel.assign(rels,ns,string::npos);
+                        ns = string::npos;
+                    }else{
+                        rel.assign(rels,ns,s-ns);
+                        ns = s;
+                    }
+                    if(rel=="openid.server")
+                        copy_trim_whitespace(html_SEP.xrd_URI,t.attrs["href"]);
+                    else if(rel=="openid.delegate")
+                        copy_trim_whitespace(html_SEP.openid_Delegate,t.attrs["href"]);
+                }
+            }
+        }else if( is_element(t,"head") )
+            state = state_stopping_head;
+        else if( is_qelement(t,NSURI_XRD "\tXRD")) {
+            if( !(
+                        (
+                         xri_mode
+                         && t.auth_info.canonical_id.empty()
+                        ) ||
+                        t.auth_info.auth_SEP.xrd_Type.empty()
+                 ) )
+                auth_info = t.auth_info;
+        }else if( tree.size()>1 ) {
+            parser_node_t& p = tree.parent();
+            if( is_qelement(p,NSURI_XRD "\tService") ) {
+                if( is_qelement(t,NSURI_XRD "\tType") ) {
+                    if(t.content==STURI_OPENID10) {
+                        string tmp; copy_trim_whitespace(tmp,t.content);
+                        p.auth_info.auth_SEP.xrd_Type.insert(tmp);
+                    }
+                }else if( is_qelement(t,NSURI_XRD "\tURI") )
+                    copy_trim_whitespace(p.auth_info.auth_SEP.xrd_URI,t.content);
+                else if( is_qelement(t,NSURI_OPENID10 "\tDelegate") )
+                    copy_trim_whitespace(p.auth_info.auth_SEP.openid_Delegate,t.content);
+            }else if( is_qelement(p,NSURI_XRD "\tXRD") ) {
+                if(is_qelement(t,NSURI_XRD "\tService") ) {
+                    if( !t.auth_info.auth_SEP.xrd_Type.empty() ) {
+                        parser_node_t::attrs_t::const_iterator ip
+                            = t.attrs.find("priority");
+                        if(ip!=t.attrs.end()) {
+                            const char *nptr = ip->second.c_str();
+                            char *eptr = 0;
+                            t.auth_info.auth_SEP.priority = strtol(nptr,&eptr,10);
+                            if(nptr==eptr)
+                                t.auth_info.auth_SEP.priority = LONG_MAX;
+                        }
+                        if( (t.auth_info.auth_SEP.priority < p.auth_info.auth_SEP.priority)
+                                || p.auth_info.auth_SEP.xrd_Type.empty() )
+                            p.auth_info.auth_SEP = t.auth_info.auth_SEP;
+                    }
+                }else if( is_qelement(t,NSURI_XRD "\tCanonicalID") )
+                    copy_trim_whitespace(p.auth_info.canonical_id,t.content);
+            }
+        }
+        
+        tree.pop();
+    }
+
+    size_t openid_service_resolver_t::write(void *p,size_t s,size_t nm) {
+        if(state != state_parse)
+            return 0;
+        /* TODO: limit total size */
+        size_t bytes = s*nm;
+        parse((const char *)p,bytes,false);
+        return bytes;
+    }
+
+    size_t openid_service_resolver_t::header(void *p,size_t s,size_t nm) {
+        size_t bytes = s*nm;
+        const char *h = (const char *)p;
+        const char *colon = (const char*)memchr(p,':',bytes);
+        const char *space = (const char*)memchr(p,' ',bytes);
+        if(space && ( (!colon) || space<colon ) ) {
+            xrds_location.clear(); http_content_type.clear();
+        }else if(colon) {
+            const char *hv = ++colon;
+            int hnl = colon-h;
+            int rb;
+            for(rb = bytes-hnl-1;
+                    rb>0 && isspace(*hv);
+                    ++hv,--rb );
+            while(rb>0 && isspace(hv[rb-1]))
+                --rb;
+            if(rb) {
+                if( (hnl >= sizeof(LOCATION_HEADER))
+                        && !strncasecmp(h,LOCATION_HEADER ":",
+                            sizeof(LOCATION_HEADER)) ) {
+                    xrds_location.assign(hv,rb);
+                }else if( (hnl >= sizeof("Content-Type"))
+                        && !strncasecmp(h,"Content-Type:",
+                            sizeof("Content-Type")) ) {
+                    const char *sc = (const char*)memchr(
+                            hv,';',rb);
+                    http_content_type.assign(
+                            hv,sc?(sc-hv):rb );
+                }
+            }
+        }
+        return curl_t::header(p,s,nm);
+    }
+
+    void openid_service_resolver_t::discover_service(const string& url,bool xri) {
+        CURLcode r = easy_setopt(CURLOPT_URL,url.c_str());
+        if(r)
+            throw opkele::exception_curl(OPKELE_CP_ "failed to set curly urlie",r);
+
+        (*(expat_t*)this) = parser_create_ns();
+        set_user_data(); set_element_handler();
+        set_character_data_handler();
+        tree.clear();
+        state = state_parse;
+
+        r = easy_perform();
+        if(r && r!=CURLE_WRITE_ERROR)
+            throw exception_curl(OPKELE_CP_ "failed to perform curly request",r);
+
+        parse(0,0,true);
+        while(!tree.empty()) pop_tag();
+    }
+
+    const openid_auth_info_t& openid_service_resolver_t::resolve(const string& id) {
+        auth_info = openid_auth_info_t();
+        html_SEP = openid_auth_SEP_t();
+
+        string::size_type fns = id.find_first_not_of(whitespace);
+        if(fns==string::npos)
+            throw opkele::bad_input(OPKELE_CP_ "whitespace-only identity");
+        string::size_type lns = id.find_last_not_of(whitespace);
+        assert(lns!=string::npos);
+        if(!strncasecmp(
+                    id.c_str()+fns,"xri://",
+                    sizeof("xri://")-1))
+            fns+=sizeof("xri://")-1;
+        string nid(id,fns,lns-fns+1);
+        if(nid.empty())
+            throw opkele::bad_input(OPKELE_CP_ "nothing significant in identity");
+        if(strchr("=@+$!(",*nid.c_str())) {
+            discover_service(
+                    xri_proxy + util::url_encode(nid) +
+                    "?_xrd_t=" STURI_OPENID10 "&_xrd_r=application/xrd+xml;sep=true",
+                    true );
+            if(auth_info.canonical_id.empty()
+                    || auth_info.auth_SEP.xrd_Type.empty() )
+                throw opkele::failed_lookup(OPKELE_CP_ "no OpenID service for XRI found");
+            return auth_info;
+        }else{
+            const char *np = nid.c_str();
+            if( (strncasecmp(np,"http",4) || strncmp(
+                            tolower(*(np+4))=='s'? np+5 : np+4, "://", 3))
+#ifndef NDEBUG
+                    && strncasecmp(np,"file:///",sizeof("file:///")-1)
+        #endif  /* XXX: or how do I let tests work? */
+                    )
+                nid.insert(0,"http://");
+            string::size_type fp = nid.find('#');
+            if(fp!=string::npos) {
+                string::size_type qp = nid.find('?');
+                if(qp==string::npos || qp<fp) {
+                    nid.erase(fp);
+                }else if(qp>fp)
+                    nid.erase(fp,qp-fp);
+            }
+            discover_service(nid);
+            const char *eu = 0;
+            CURLcode r = easy_getinfo(CURLINFO_EFFECTIVE_URL,&eu);
+            if(r)
+                throw exception_curl(OPKELE_CP_ "failed to get CURLINFO_EFFECTIVE_URL",r);
+            string canonicalized_id = util::rfc_3986_normalize_uri(eu);
+            if(xrds_location.empty()) {
+                if(auth_info.auth_SEP.xrd_Type.empty()) {
+                    if(html_SEP.xrd_URI.empty())
+                        throw opkele::failed_lookup(OPKELE_CP_ "no OpenID service discovered");
+                    auth_info.auth_SEP = html_SEP;
+                    auth_info.auth_SEP.xrd_Type.clear(); auth_info.auth_SEP.xrd_Type.insert( STURI_OPENID10 );
+                    auth_info.canonical_id = canonicalized_id;
+                }else{
+                    if(auth_info.canonical_id.empty())
+                        auth_info.canonical_id = canonicalized_id;
+                }
+                return auth_info;
+            }else{
+                discover_service(xrds_location);
+                if(auth_info.auth_SEP.xrd_Type.empty())
+                    throw opkele::failed_lookup(OPKELE_CP_ "no OpenID service found in Yadis document");
+                if(auth_info.canonical_id.empty())
+                    auth_info.canonical_id = canonicalized_id;
+                return auth_info;
+            }
+        }
+    }
+
+}
diff --git a/lib/util.cc b/lib/util.cc
index ac70938..69d37b5 100644
--- a/lib/util.cc
+++ b/lib/util.cc
@@ -173,21 +173,29 @@ namespace opkele {
          * - if there's no path component, add '/'
          */
          string rfc_3986_normalize_uri(const string& uri) {
+             static const char *whitespace = " \t\r\n";
              string rv;
-             string::size_type colon = uri.find(':');
+             string::size_type ns = uri.find_first_not_of(whitespace);
+             if(ns==string::npos)
+                 throw bad_input(OPKELE_CP_ "Can't normalize empty URI");
+             string::size_type colon = uri.find(':',ns);
              if(colon==string::npos)
                  throw bad_input(OPKELE_CP_ "No scheme specified in URI");
              transform(
-                     uri.begin(), uri.begin()+colon+1,
+                     uri.begin()+ns, uri.begin()+colon+1,
                      back_inserter(rv), ::tolower );
              bool s;
              if(rv=="http:")
                  s = false;
              else if(rv=="https:")
                  s = true;
+#ifndef NDEBUG
+             else if(rv=="file:")
+                 s = false;
+#endif /* XXX: or try to make tests work some other way */
              else
                  throw not_implemented(OPKELE_CP_ "Only http(s) URIs can be normalized here");
-             string::size_type ul = uri.length();
+             string::size_type ul = uri.find_last_not_of(whitespace)+1;
              if(ul <= (colon+3))
                  throw bad_input(OPKELE_CP_ "Unexpected end of URI being normalized encountered");
              if(uri[colon+1]!='/' || uri[colon+2]!='/')
@@ -196,7 +204,7 @@ namespace opkele {
              string::size_type interesting = uri.find_first_of(":/#?",colon+3);
              if(interesting==string::npos) {
                  transform(
-                         uri.begin()+colon+3,uri.end(),
+                         uri.begin()+colon+3,uri.begin()+ul,
                          back_inserter(rv), ::tolower );
                  rv += '/'; return rv;
              }
diff --git a/test/.gitignore b/test/.gitignore
index 918b3c9..5ce4dc9 100644
--- a/test/.gitignore
+++ b/test/.gitignore
@@ -2,3 +2,4 @@
 /.libs
 /test
 *.o
+/openid_resolve
diff --git a/test/Makefile.am b/test/Makefile.am
index 4b78087..5aa87b3 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -1,4 +1,4 @@
-noinst_PROGRAMS = test
+noinst_PROGRAMS = test openid_resolve
 
 DEFAULT_INCLUDES = -I${top_builddir}
 INCLUDES = -I${top_srcdir}/include/ ${KONFORKA_CFLAGS}
@@ -10,3 +10,6 @@ EXTRA_DIST=$(addsuffix .html,$(addprefix html/, \
         empty head-in-body hkn-delegate hkn-server hkn in-body \
         unclosed-head spaced-links spaced-link-attrs 2rels \
         ))
+
+openid_resolve_SOURCES = openid_resolve.cc
+openid_resolve_LDADD = ${top_builddir}/lib/libopkele.la
diff --git a/test/openid_resolve.cc b/test/openid_resolve.cc
new file mode 100644
index 0000000..31c7a6a
--- a/dev/null
+++ b/test/openid_resolve.cc
@@ -0,0 +1,36 @@
+#include <iostream>
+#include <stdexcept>
+#include <iterator>
+#include <algorithm>
+using namespace std;
+#include <opkele/exception.h>
+#include <opkele/openid_service_resolver.h>
+
+int main(int argc,char **argv) {
+    try {
+        if(argc<2)
+            throw opkele::exception(OPKELE_CP_ "Please, give me something to resolve");
+        opkele::openid_service_resolver_t resolver;
+        for(int a=1;a<argc;++a) {
+            const opkele::openid_auth_info_t& iai = resolver.resolve(argv[a]);
+            clog
+                << "====================" << endl
+                << "canonical id is " << iai.canonical_id << endl
+                << endl
+                << "service priority is " << iai.auth_SEP.priority << endl
+                << "service types are " ;
+            copy(
+                    iai.auth_SEP.xrd_Type.begin(), iai.auth_SEP.xrd_Type.end(),
+                    ostream_iterator<string>(clog," ") );
+            clog << endl
+                << "service URI is " << iai.auth_SEP.xrd_URI  << endl;
+            if(!iai.auth_SEP.openid_Delegate.empty())
+                clog << "openid:Delegate is " << iai.auth_SEP.openid_Delegate << endl;
+            clog << endl;
+        }
+    }catch(exception& e) {
+        cerr << "oops: " << e.what() << endl;
+        _exit(1);
+    }
+    _exit(0);
+}