make canonicalize follow redirects

 - renamed old consumer_t::canonicalize to consumer_t::normalize
 - made the real canonicalize virtual to allow caching layer

2 files changed, 34 insertions, 3 deletions

diff --git a/include/opkele/consumer.h b/include/opkele/consumer.h
index fdb6119..042e2d1 100644
--- a/include/opkele/consumer.h
+++ b/include/opkele/consumer.h
@@ -1,142 +1,149 @@
 #ifndef __OPKELE_CONSUMER_H
 #define __OPKELE_CONSUMER_H
 
 #include <opkele/types.h>
 #include <opkele/extension.h>
 
 /**
  * @file
  * @brief OpenID consumer-side functionality
  */
 
 namespace opkele {
 
     /**
      * implementation of basic consumer functionality
      */
     class consumer_t {
 	public:
 
 	    /**
 	     * store association. The function should be overridden in the real
 	     * implementation to provide persistent associations store.
 	     * @param server the OpenID server
 	     * @param handle association handle
 	     * @param secret the secret associated with the server and handle
 	     * @param expires_in the number of seconds until the handle is expired
 	     * @return the auto_ptr<> for the newly allocated association_t object
 	     */
 	    virtual assoc_t store_assoc(const string& server,const string& handle,const secret_t& secret,int expires_in) = 0;
 	    /**
 	     * retrieve stored association. The function should be overridden
 	     * in the real implementation to provide persistent assocations
 	     * store.
 	     * @param server the OpenID server
 	     * @param handle association handle
 	     * @return the autho_ptr<> for the newly allocated association_t object
 	     * @throw failed_lookup in case of error
 	     */
 	    virtual assoc_t retrieve_assoc(const string& server,const string& handle) = 0;
 	    /**
 	     * invalidate stored association. The function should be overridden
 	     * in the real implementation of the consumer.
 	     * @param server the OpenID server
 	     * @param handle association handle
 	     */
 	    virtual void invalidate_assoc(const string& server,const string& handle) = 0;
 	    /**
 	     * retrieve any unexpired association for the server. If the
 	     * function is not overridden in the real implementation, the new
 	     * association will be established for each request.
 	     * @param server the OpenID server
 	     * @return the auto_ptr<> for the newly allocated association_t object
 	     * @throw failed_lookup in case of absence of the handle
 	     */
 	    virtual assoc_t find_assoc(const string& server);
 
 	    /**
 	     * retrieve the metainformation contained in link tags from the
 	     * page pointed by url. the function may implement caching of the
 	     * information.
 	     * @param url url to harvest for link tags
 	     * @param server reference to the string object where to put
 	     * openid.server value
 	     * @param delegate reference to the string object where to put the
 	     * openid.delegate value (if any)
 	     */
 	    virtual void retrieve_links(const string& url,string& server,string& delegate);
 
 	    /**
 	     * perform the associate request to OpenID server.
 	     * @param server the OpenID server
 	     * @return the auto_ptr<> for the newly allocated association_t
 	     * object, representing established association
 	     * @throw exception in case of error
 	     */
 	    assoc_t associate(const string& server);
 	    /**
 	     * prepare the parameters for the checkid_immediate
 	     * request.
 	     * @param identity the identity to verify
 	     * @param return_to the return_to url to pass with the request
 	     * @param trust_root the trust root to advertise with the request
 	     * @param ext pointer to an extension(s) hooks object
 	     * @return the location string
 	     * @throw exception in case of error
 	     */
 	    virtual string checkid_immediate(const string& identity,const string& return_to,const string& trust_root="",extension_t *ext=0);
 	    /**
 	     * prepare the parameters for the checkid_setup
 	     * request.
 	     * @param identity the identity to verify
 	     * @param return_to the return_to url to pass with the request
 	     * @param trust_root the trust root to advertise with the request
 	     * @param ext pointer to an extension(s) hooks object
 	     * @return the location string
 	     * @throw exception in case of error
 	     */
 	    virtual string checkid_setup(const string& identity,const string& return_to,const string& trust_root="",extension_t *ext=0);
 	    /**
 	     * the actual implementation behind checkid_immediate() and
 	     * checkid_setup() functions.
 	     * @param mode checkid_* mode - either mode_checkid_immediate or mode_checkid_setup
 	     * @param identity the identity to verify
 	     * @param return_to the return_to url to pass with the request
 	     * @param trust_root the trust root to advertise with the request
 	     * @param ext pointer to an extension(s) hooks object
 	     * @return the location string
 	     * @throw exception in case of error
 	     */
 	    virtual string checkid_(mode_t mode,const string& identity,const string& return_to,const string& trust_root="",extension_t *ext=0);
 	    /**
 	     * verify the id_res response
 	     * @param pin the response parameters
 	     * @param identity the identity being checked (if not specified,
 	     * @param ext pointer to an extension(s) hooks object
 	     * extracted from the openid.identity parameter
 	     * @throw id_res_mismatch in case of signature mismatch
 	     * @throw id_res_setup in case of openid.user_setup_url failure
 	     * (supposedly checkid_immediate only)
 	     * @throw id_res_failed in case of failure
 	     * @throw exception in case of other failures
 	     */
 	    virtual void id_res(const params_t& pin,const string& identity="",extension_t *ext=0);
 	    /**
 	     * perform a check_authentication request.
 	     * @param server the OpenID server
 	     * @param p request parameters
 	     */
 	    void check_authentication(const string& server,const params_t& p);
 
 	    /**
-	     * make URL canonical, by adding http:// and trailing slash, if needed.
+	     * normalize URL by adding http:// and trailing slash if needed.
+	     * @param url
+	     * @return normalized url
+	     */
+	    static string normalize(const string& url);
+
+	    /**
+	     * Canonicalize URL, by normalizing its appearance and following redirects.
 	     * @param url
 	     * @return canonicalized url
 	     */
-	    static string canonicalize(const string& url);
+	    virtual string canonicalize(const string& url);
 
     };
 
 }
 
 #endif /* __OPKELE_CONSUMER_H */
diff --git a/lib/consumer.cc b/lib/consumer.cc
index 282f0cc..dd8e150 100644
--- a/lib/consumer.cc
+++ b/lib/consumer.cc
@@ -1,345 +1,369 @@
 #include <algorithm>
 #include <cassert>
 #include <opkele/util.h>
 #include <opkele/exception.h>
 #include <opkele/data.h>
 #include <opkele/consumer.h>
 #include <openssl/sha.h>
 #include <openssl/hmac.h>
 #include <curl/curl.h>
 #include <pcre++.h>
 
 #include <iostream>
 
 #include "config.h"
 
 namespace opkele {
     using namespace std;
 
     class curl_t {
 	public:
 	    CURL *_c;
 
 	    curl_t() : _c(0) { }
 	    curl_t(CURL *c) : _c(c) { }
 	    ~curl_t() throw() { if(_c) curl_easy_cleanup(_c); }
 
 	    curl_t& operator=(CURL *c) { if(_c) curl_easy_cleanup(_c); _c=c; return *this; }
 
 	    operator const CURL*(void) const { return _c; }
 	    operator CURL*(void) { return _c; }
     };
 
     static CURLcode curl_misc_sets(CURL* c) {
 	CURLcode r;
 	(r=curl_easy_setopt(c,CURLOPT_FOLLOWLOCATION,1))
 	|| (r=curl_easy_setopt(c,CURLOPT_MAXREDIRS,5))
 	|| (r=curl_easy_setopt(c,CURLOPT_DNS_CACHE_TIMEOUT,120))
 	|| (r=curl_easy_setopt(c,CURLOPT_DNS_USE_GLOBAL_CACHE,1))
 	|| (r=curl_easy_setopt(c,CURLOPT_USERAGENT,PACKAGE_NAME"/"PACKAGE_VERSION))
 	|| (r=curl_easy_setopt(c,CURLOPT_TIMEOUT,20))
 #ifdef	DISABLE_CURL_SSL_VERIFYHOST
 	|| (r=curl_easy_setopt(c,CURLOPT_SSL_VERIFYHOST,0))
 #endif
 #ifdef	DISABLE_CURL_SSL_VERIFYPEER
 	|| (r=curl_easy_setopt(c,CURLOPT_SSL_VERIFYPEER,0))
 #endif
 	;
 	return r;
     }
 
     static size_t _curl_tostring(void *ptr,size_t size,size_t nmemb,void *stream) {
 	string *str = (string*)stream;
 	size_t bytes = size*nmemb;
 	size_t get = min(16384-str->length(),bytes);
 	str->append((const char*)ptr,get);
 	return get;
     }
 
     assoc_t consumer_t::associate(const string& server) {
 	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()");
 	string request = 
 	    "openid.mode=associate"
 	    "&openid.assoc_type=HMAC-SHA1"
 	    "&openid.session_type=DH-SHA1"
 	    "&openid.dh_consumer_public=";
 	request += util::url_encode(util::bignum_to_base64(dh->pub_key));
 	curl_t curl = curl_easy_init();
 	if(!curl)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_init()");
 	string response;
 	CURLcode r;
 	(r=curl_misc_sets(curl))
 	|| (r=curl_easy_setopt(curl,CURLOPT_URL,server.c_str()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POST,1))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POSTFIELDS,request.data()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POSTFIELDSIZE,request.length()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,_curl_tostring))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEDATA,&response))
 	;
 	if(r)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_setopt()",r);
 	if(r=curl_easy_perform(curl))
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_perform()",r);
 	params_t p; p.parse_keyvalues(response);
 	if(p.has_param("assoc_type") && p.get_param("assoc_type")!="HMAC-SHA1")
 	    throw bad_input(OPKELE_CP_ "unsupported assoc_type");
 	string st;
 	if(p.has_param("session_type")) st = p.get_param("session_type");
 	if((!st.empty()) && st!="DH-SHA1")
 	    throw bad_input(OPKELE_CP_ "unsupported session_type");
 	secret_t secret;
 	if(st.empty()) {
 	    secret.from_base64(p.get_param("mac_key"));
 	}else{
 	    util::bignum_t s_pub = util::base64_to_bignum(p.get_param("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_sha1[SHA_DIGEST_LENGTH];
 	    SHA1(ckptr,cklen,key_sha1);
 	    secret.enxor_from_base64(key_sha1,p.get_param("enc_mac_key"));
 	}
 	int expires_in = 0;
 	if(p.has_param("expires_in")) {
 	    expires_in = util::string_to_long(p.get_param("expires_in"));
 	}else if(p.has_param("issued") && p.has_param("expiry")) {
 	    expires_in = util::w3c_to_time(p.get_param("expiry"))-util::w3c_to_time(p.get_param("issued"));
 	}else
 	    throw bad_input(OPKELE_CP_ "no expiration information");
 	return store_assoc(server,p.get_param("assoc_handle"),secret,expires_in);
     }
 
     string consumer_t::checkid_immediate(const string& identity,const string& return_to,const string& trust_root,extension_t *ext) {
 	return checkid_(mode_checkid_immediate,identity,return_to,trust_root,ext);
     }
     string consumer_t::checkid_setup(const string& identity,const string& return_to,const string& trust_root,extension_t *ext) {
 	return checkid_(mode_checkid_setup,identity,return_to,trust_root,ext);
     }
     string consumer_t::checkid_(mode_t mode,const string& identity,const string& return_to,const string& trust_root,extension_t *ext) {
 	params_t p;
 	if(mode==mode_checkid_immediate)
 	    p["mode"]="checkid_immediate";
 	else if(mode==mode_checkid_setup)
 	    p["mode"]="checkid_setup";
 	else
 	    throw bad_input(OPKELE_CP_ "unknown checkid_* mode");
 	string iurl = canonicalize(identity);
 	string server, delegate;
 	retrieve_links(iurl,server,delegate);
 	p["identity"] = delegate.empty()?iurl:delegate;
 	if(!trust_root.empty())
 	    p["trust_root"] = trust_root;
 	p["return_to"] = return_to;
 	try {
 	    string ah = find_assoc(server)->handle();
 	    p["assoc_handle"] = ah;
 	}catch(failed_lookup& fl) {
 	    string ah = associate(server)->handle();
 	    p["assoc_handle"] = ah;
 	}
 	if(ext) ext->checkid_hook(p,identity);
 	return p.append_query(server);
     }
 
     void consumer_t::id_res(const params_t& pin,const string& identity,extension_t *ext) {
 	if(pin.has_param("openid.user_setup_url"))
 	    throw id_res_setup(OPKELE_CP_ "assertion failed, setup url provided",pin.get_param("openid.user_setup_url"));
 	string server,delegate;
 	retrieve_links(identity.empty()?pin.get_param("openid.identity"):canonicalize(identity),server,delegate);
 	params_t ps;
 	try {
 	    assoc_t assoc = retrieve_assoc(server,pin.get_param("openid.assoc_handle"));
 	    const string& sigenc = pin.get_param("openid.sig");
 	    vector<unsigned char> sig;
 	    util::decode_base64(sigenc,sig);
 	    const string& slist = pin.get_param("openid.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 += ':';
 		f.insert(0,"openid.");
 		kv += pin.get_param(f);
 		kv += '\n';
 		if(ext) ps[f.substr(sizeof("openid.")-1)] = pin.get_param(f);
 		if(co==string::npos)
 		    break;
 		p = co+1;
 	    }
 	    secret_t secret = assoc->secret();
 	    unsigned int md_len = 0;
 	    unsigned char *md = HMAC(
 		    EVP_sha1(),
 		    &(secret.front()),secret.size(),
 		    (const unsigned char *)kv.data(),kv.length(),
 		    0,&md_len);
 	    if(sig.size()!=md_len || memcmp(&(sig.front()),md,md_len))
 		throw id_res_mismatch(OPKELE_CP_ "signature mismatch");
 	}catch(failed_lookup& e) { /* XXX: more specific? */
 	    const string& slist = pin.get_param("openid.signed");
 	    string::size_type pp = 0;
 	    params_t p;
 	    while(true) {
 		string::size_type co = slist.find(',',pp);
 		string f = "openid.";
 		f += (co==string::npos)?slist.substr(pp):slist.substr(pp,co-pp);
 		p[f] = pin.get_param(f);
 		if(co==string::npos)
 		    break;
 		pp = co+1;
 	    }
 	    p["openid.assoc_handle"] = pin.get_param("openid.assoc_handle");
 	    p["openid.sig"] = pin.get_param("openid.sig");
 	    p["openid.signed"] = pin.get_param("openid.signed");
 	    try {
 		string ih = pin.get_param("openid.invalidate_handle");
 		p["openid.invalidate_handle"] = ih;
 	    }catch(failed_lookup& fl) { }
 	    try {
 		check_authentication(server,p);
 	    }catch(failed_check_authentication& fca) {
 		throw id_res_failed(OPKELE_CP_ "failed to check_authentication()");
 	    }
 	}
 	if(ext) ext->id_res_hook(pin,ps,identity);
     }
 
     void consumer_t::check_authentication(const string& server,const params_t& p) {
 	string request = "openid.mode=check_authentication";
 	for(params_t::const_iterator i=p.begin();i!=p.end();++i) {
 	    if(i->first!="openid.mode") {
 		request += '&';
 		request += i->first;
 		request += '=';
 		request += util::url_encode(i->second);
 	    }
 	}
 	curl_t curl = curl_easy_init();
 	if(!curl)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_init()");
 	string response;
 	CURLcode r;
 	(r=curl_misc_sets(curl))
 	|| (r=curl_easy_setopt(curl,CURLOPT_URL,server.c_str()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POST,1))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POSTFIELDS,request.data()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_POSTFIELDSIZE,request.length()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,_curl_tostring))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEDATA,&response))
 	;
 	if(r)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_setopt()",r);
 	if(r=curl_easy_perform(curl))
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_perform()",r);
 	params_t pp; pp.parse_keyvalues(response);
 	if(pp.has_param("invalidate_handle"))
 	    invalidate_assoc(server,pp.get_param("invalidate_handle"));
 	if(pp.has_param("is_valid")) {
 	    if(pp.get_param("is_valid")=="true")
 		return;
 	}else if(pp.has_param("lifetime")) {
 	    if(util::string_to_long(pp.get_param("lifetime")))
 		return;
 	}
 	throw failed_check_authentication(OPKELE_CP_ "failed to verify response");
     }
 
     void consumer_t::retrieve_links(const string& url,string& server,string& delegate) {
 	server.erase();
 	delegate.erase();
 	curl_t curl = curl_easy_init();
 	if(!curl)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_init()");
 	string html;
 	CURLcode r;
 	(r=curl_misc_sets(curl))
 	|| (r=curl_easy_setopt(curl,CURLOPT_URL,url.c_str()))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,_curl_tostring))
 	|| (r=curl_easy_setopt(curl,CURLOPT_WRITEDATA,&html))
 	;
 	if(r)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_setopt()",r);
 	r = curl_easy_perform(curl);
 	if(r && r!=CURLE_WRITE_ERROR)
 	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_perform()",r);
 	pcrepp::Pcre bre("<body\\b",PCRE_CASELESS);
 	// strip out everything past body
 	if(bre.search(html))
 	    html.erase(bre.get_match_start());
 	pcrepp::Pcre hdre("<head[^>]*>",PCRE_CASELESS);
 	if(!hdre.search(html))
 	    throw bad_input(OPKELE_CP_ "failed to find head");
 	html.erase(0,hdre.get_match_end()+1);
 	pcrepp::Pcre lre("<link\\b([^>]+)>",PCRE_CASELESS),
 	    rre("\\brel=['\"]([^'\"]+)['\"]",PCRE_CASELESS),
 	    hre("\\bhref=['\"]([^'\"]+)['\"]",PCRE_CASELESS);
 	while(lre.search(html)) {
 	    string attrs = lre[0];
 	    html.erase(0,lre.get_match_end()+1);
 	    if(!(rre.search(attrs)&&hre.search(attrs)))
 		continue;
 	    if(rre[0]=="openid.server") {
 		server = hre[0];
 		if(!delegate.empty())
 		    break;
 	    }else if(rre[0]=="openid.delegate") {
 		delegate = hre[0];
 		if(!server.empty())
 		    break;
 	    }
 	}
 	if(server.empty())
 	    throw failed_assertion(OPKELE_CP_ "The location has no openid.server declaration");
     }
 
     assoc_t consumer_t::find_assoc(const string& server) {
 	throw failed_lookup(OPKELE_CP_ "no find_assoc() provided");
     }
 
-    string consumer_t::canonicalize(const string& url) {
+    string consumer_t::normalize(const string& url) {
 	string rv = url;
 	// strip leading and trailing spaces
 	string::size_type i = rv.find_first_not_of(" \t\r\n");
 	if(i==string::npos)
 	    throw bad_input(OPKELE_CP_ "empty URL");
 	if(i)
 	    rv.erase(0,i);
 	i = rv.find_last_not_of(" \t\r\n");
 	assert(i!=string::npos);
 	if(i<(rv.length()-1))
 	    rv.erase(i+1);
 	// add missing http://
 	i = rv.find("://");
 	if(i==string::npos) { // primitive. but do we need more?
 	    rv.insert(0,"http://");
 	    i = sizeof("http://")-1;
 	}else{
 	    i += sizeof("://")-1;
 	}
 	string::size_type qm = rv.find('?',i);
 	string::size_type sl = rv.find('/',i);
 	if(qm!=string::npos) {
 	    if(sl==string::npos || sl>qm)
 		rv.insert(qm,1,'/');
 	}else{
 	    if(sl==string::npos)
 		rv += '/';
 	}
 	return rv;
     }
 
+    string consumer_t::canonicalize(const string& url) {
+	string rv = normalize(url);
+	curl_t curl = curl_easy_init();
+	if(!curl)
+	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_init()");
+	string html;
+	CURLcode r;
+	(r=curl_misc_sets(curl))
+	|| (r=curl_easy_setopt(curl,CURLOPT_URL,rv.c_str()))
+	|| (r=curl_easy_setopt(curl,CURLOPT_NOBODY,1))
+	;
+	if(r)
+	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_setopt()",r);
+	r = curl_easy_perform(curl);
+	if(r)
+	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_perform()",r);
+	const char *eu = 0;
+	r = curl_easy_getinfo(curl,CURLINFO_EFFECTIVE_URL,&eu);
+	if(r)
+	    throw exception_curl(OPKELE_CP_ "failed to curl_easy_getinfo(..CURLINFO_EFFECTIVE_URL..)",r);
+	rv = eu;
+	return normalize(rv);
+    }
+
 }