xmltooling/soap/impl/CURLSOAPTransport.cpp

   1 /*
   2  *  Copyright 2001-2010 Internet2
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 /**
  18  * CURLSOAPTransport.cpp
  19  *
  20  * libcurl-based SOAPTransport implementation.
  21  */
  22
  23 #include "internal.h"
  24 #include "exceptions.h"
  25 #include "logging.h"
  26 #include "security/CredentialCriteria.h"
  27 #include "security/OpenSSLTrustEngine.h"
  28 #include "security/OpenSSLCredential.h"
  29 #include "soap/HTTPSOAPTransport.h"
  30 #include "soap/OpenSSLSOAPTransport.h"
  31 #include "util/NDC.h"
  32 #include "util/Threads.h"
  33
  34 #include <list>
  35 #include <curl/curl.h>
  36 #include <openssl/x509_vfy.h>
  37
  38 using namespace xmltooling::logging;
  39 using namespace xmltooling;
  40 using namespace std;
  41
  42 namespace xmltooling {
  43
  44     // Manages cache of socket connections via CURL handles.
  45     class XMLTOOL_DLLLOCAL CURLPool
  46     {
  47     public:
  48         CURLPool() : m_size(0), m_lock(Mutex::create()),
  49             m_log(Category::getInstance(XMLTOOLING_LOGCAT".SOAPTransport.CURL")) {}
  50         ~CURLPool();
  51
  52         CURL* get(const SOAPTransport::Address& addr);
  53         void put(const char* from, const char* to, const char* endpoint, CURL* handle);
  54
  55     private:
  56         typedef map<string,vector<CURL*> > poolmap_t;
  57         poolmap_t m_bindingMap;
  58         list< vector<CURL*>* > m_pools;
  59         long m_size;
  60         Mutex* m_lock;
  61         Category& m_log;
  62     };
  63
  64     static XMLTOOL_DLLLOCAL CURLPool* g_CURLPool = nullptr;
  65
  66     class XMLTOOL_DLLLOCAL CURLSOAPTransport : public HTTPSOAPTransport, public OpenSSLSOAPTransport
  67     {
  68     public:
  69         CURLSOAPTransport(const Address& addr)
  70             : m_sender(addr.m_from ? addr.m_from : ""), m_peerName(addr.m_to ? addr.m_to : ""), m_endpoint(addr.m_endpoint),
  71                 m_handle(nullptr), m_headers(nullptr),
  72 #ifndef XMLTOOLING_NO_XMLSEC
  73                     m_cred(nullptr), m_trustEngine(nullptr), m_peerResolver(nullptr), m_mandatory(false),
  74 #endif
  75                     m_openssl_ops(SSL_OP_ALL|SSL_OP_NO_SSLv2), m_ssl_callback(nullptr), m_ssl_userptr(nullptr),
  76                     m_chunked(true), m_authenticated(false), m_cacheTag(nullptr) {
  77             m_handle = g_CURLPool->get(addr);
  78             curl_easy_setopt(m_handle,CURLOPT_URL,addr.m_endpoint);
  79             curl_easy_setopt(m_handle,CURLOPT_CONNECTTIMEOUT,15);
  80             curl_easy_setopt(m_handle,CURLOPT_TIMEOUT,30);
  81             curl_easy_setopt(m_handle,CURLOPT_HTTPAUTH,0);
  82             curl_easy_setopt(m_handle,CURLOPT_USERPWD,nullptr);
  83             curl_easy_setopt(m_handle,CURLOPT_SSL_VERIFYHOST,2);
  84             curl_easy_setopt(m_handle,CURLOPT_HEADERDATA,this);
  85             m_headers=curl_slist_append(m_headers,"Content-Type: text/xml");
  86         }
  87
  88         virtual ~CURLSOAPTransport() {
  89             curl_slist_free_all(m_headers);
  90             curl_easy_setopt(m_handle,CURLOPT_ERRORBUFFER,nullptr);
  91             curl_easy_setopt(m_handle,CURLOPT_PRIVATE,m_authenticated ? "secure" : nullptr); // Save off security "state".
  92             g_CURLPool->put(m_sender.c_str(), m_peerName.c_str(), m_endpoint.c_str(), m_handle);
  93         }
  94
  95         bool isConfidential() const {
  96             return m_endpoint.find("https")==0;
  97         }
  98
  99         bool setConnectTimeout(long timeout) {
 100             return (curl_easy_setopt(m_handle,CURLOPT_CONNECTTIMEOUT,timeout)==CURLE_OK);
 101         }
 102
 103         bool setTimeout(long timeout) {
 104             return (curl_easy_setopt(m_handle,CURLOPT_TIMEOUT,timeout)==CURLE_OK);
 105         }
 106
 107         bool setAuth(transport_auth_t authType, const char* username=nullptr, const char* password=nullptr);
 108
 109         bool setVerifyHost(bool verify) {
 110             return (curl_easy_setopt(m_handle,CURLOPT_SSL_VERIFYHOST,verify ? 2 : 0)==CURLE_OK);
 111         }
 112
 113 #ifndef XMLTOOLING_NO_XMLSEC
 114         bool setCredential(const Credential* cred=nullptr) {
 115             const OpenSSLCredential* down = dynamic_cast<const OpenSSLCredential*>(cred);
 116             if (!down) {
 117                 m_cred = nullptr;
 118                 return (cred==nullptr);
 119             }
 120             m_cred = down;
 121             return true;
 122         }
 123
 124         bool setTrustEngine(
 125             const X509TrustEngine* trustEngine=nullptr,
 126             const CredentialResolver* peerResolver=nullptr,
 127             CredentialCriteria* criteria=nullptr,
 128             bool mandatory=true
 129             ) {
 130             const OpenSSLTrustEngine* down = dynamic_cast<const OpenSSLTrustEngine*>(trustEngine);
 131             if (!down) {
 132                 m_trustEngine = nullptr;
 133                 m_peerResolver = nullptr;
 134                 m_criteria = nullptr;
 135                 return (trustEngine==nullptr);
 136             }
 137             m_trustEngine = down;
 138             m_peerResolver = peerResolver;
 139             m_criteria = criteria;
 140             m_mandatory = mandatory;
 141             return true;
 142         }
 143
 144 #endif
 145
 146         bool useChunkedEncoding(bool chunked=true) {
 147             m_chunked = chunked;
 148             return true;
 149         }
 150
 151         bool setCacheTag(string* cacheTag) {
 152             m_cacheTag = cacheTag;
 153             return true;
 154         }
 155
 156         bool setProviderOption(const char* provider, const char* option, const char* value);
 157
 158         void send(istream& in) {
 159             send(&in);
 160         }
 161
 162         void send(istream* in=nullptr);
 163
 164         istream& receive() {
 165             return m_stream;
 166         }
 167
 168         bool isAuthenticated() const {
 169             return m_authenticated;
 170         }
 171
 172         void setAuthenticated(bool auth) {
 173             m_authenticated = auth;
 174         }
 175
 176         string getContentType() const;
 177         long getStatusCode() const;
 178
 179         bool setRequestHeader(const char* name, const char* val) {
 180             string temp(name);
 181             temp=temp + ": " + val;
 182             m_headers=curl_slist_append(m_headers,temp.c_str());
 183             return true;
 184         }
 185
 186         const vector<string>& getResponseHeader(const char* val) const;
 187
 188         bool setSSLCallback(ssl_ctx_callback_fn fn, void* userptr=nullptr) {
 189             m_ssl_callback=fn;
 190             m_ssl_userptr=userptr;
 191             return true;
 192         }
 193
 194     private:
 195         // per-call state
 196         string m_sender,m_peerName,m_endpoint,m_simplecreds;
 197         CURL* m_handle;
 198         stringstream m_stream;
 199         struct curl_slist* m_headers;
 200         map<string,vector<string> > m_response_headers;
 201         vector<string> m_saved_options;
 202 #ifndef XMLTOOLING_NO_XMLSEC
 203         const OpenSSLCredential* m_cred;
 204         const OpenSSLTrustEngine* m_trustEngine;
 205         const CredentialResolver* m_peerResolver;
 206         CredentialCriteria* m_criteria;
 207         bool m_mandatory;
 208 #endif
 209         int m_openssl_ops;
 210         ssl_ctx_callback_fn m_ssl_callback;
 211         void* m_ssl_userptr;
 212         bool m_chunked;
 213         bool m_authenticated;
 214         string* m_cacheTag;
 215
 216         friend size_t XMLTOOL_DLLLOCAL curl_header_hook(void* ptr, size_t size, size_t nmemb, void* stream);
 217         friend CURLcode XMLTOOL_DLLLOCAL xml_ssl_ctx_callback(CURL* curl, SSL_CTX* ssl_ctx, void* userptr);
 218         friend int XMLTOOL_DLLLOCAL verify_callback(X509_STORE_CTX* x509_ctx, void* arg);
 219     };
 220
 221     // libcurl callback functions
 222     size_t XMLTOOL_DLLLOCAL curl_header_hook(void* ptr, size_t size, size_t nmemb, void* stream);
 223     size_t XMLTOOL_DLLLOCAL curl_write_hook(void* ptr, size_t size, size_t nmemb, void* stream);
 224     size_t XMLTOOL_DLLLOCAL curl_read_hook( void *ptr, size_t size, size_t nmemb, void *stream);
 225     int XMLTOOL_DLLLOCAL curl_debug_hook(CURL* handle, curl_infotype type, char* data, size_t len, void* ptr);
 226     CURLcode XMLTOOL_DLLLOCAL xml_ssl_ctx_callback(CURL* curl, SSL_CTX* ssl_ctx, void* userptr);
 227 #ifndef XMLTOOLING_NO_XMLSEC
 228     int XMLTOOL_DLLLOCAL verify_callback(X509_STORE_CTX* x509_ctx, void* arg);
 229 #endif
 230
 231     SOAPTransport* CURLSOAPTransportFactory(const SOAPTransport::Address& addr)
 232     {
 233         return new CURLSOAPTransport(addr);
 234     }
 235 };
 236
 237 void xmltooling::registerSOAPTransports()
 238 {
 239     XMLToolingConfig& conf=XMLToolingConfig::getConfig();
 240     conf.SOAPTransportManager.registerFactory("http", CURLSOAPTransportFactory);
 241     conf.SOAPTransportManager.registerFactory("https", CURLSOAPTransportFactory);
 242 }
 243
 244 void xmltooling::initSOAPTransports()
 245 {
 246     g_CURLPool=new CURLPool();
 247 }
 248
 249 void xmltooling::termSOAPTransports()
 250 {
 251     delete g_CURLPool;
 252     g_CURLPool = nullptr;
 253 }
 254
 255 OpenSSLSOAPTransport::OpenSSLSOAPTransport()
 256 {
 257 }
 258
 259 OpenSSLSOAPTransport::~OpenSSLSOAPTransport()
 260 {
 261 }
 262
 263 CURLPool::~CURLPool()
 264 {
 265     for (poolmap_t::iterator i=m_bindingMap.begin(); i!=m_bindingMap.end(); i++) {
 266         for (vector<CURL*>::iterator j=i->second.begin(); j!=i->second.end(); j++)
 267             curl_easy_cleanup(*j);
 268     }
 269     delete m_lock;
 270 }
 271
 272 CURL* CURLPool::get(const SOAPTransport::Address& addr)
 273 {
 274 #ifdef _DEBUG
 275     xmltooling::NDC("get");
 276 #endif
 277     m_log.debug("getting connection handle to %s", addr.m_endpoint);
 278     string key(addr.m_endpoint);
 279     if (addr.m_from)
 280         key = key + '|' + addr.m_from;
 281     if (addr.m_to)
 282         key = key + '|' + addr.m_to;
 283     m_lock->lock();
 284     poolmap_t::iterator i=m_bindingMap.find(key);
 285
 286     if (i!=m_bindingMap.end()) {
 287         // Move this pool to the front of the list.
 288         m_pools.remove(&(i->second));
 289         m_pools.push_front(&(i->second));
 290
 291         // If a free connection exists, return it.
 292         if (!(i->second.empty())) {
 293             CURL* handle=i->second.back();
 294             i->second.pop_back();
 295             m_size--;
 296             m_lock->unlock();
 297             m_log.debug("returning existing connection handle from pool");
 298             return handle;
 299         }
 300     }
 301
 302     m_lock->unlock();
 303     m_log.debug("nothing free in pool, returning new connection handle");
 304
 305     // Create a new connection and set non-varying options.
 306     CURL* handle=curl_easy_init();
 307     if (!handle)
 308         return nullptr;
 309     curl_easy_setopt(handle,CURLOPT_NOPROGRESS,1);
 310     curl_easy_setopt(handle,CURLOPT_NOSIGNAL,1);
 311     curl_easy_setopt(handle,CURLOPT_FAILONERROR,1);
 312     curl_easy_setopt(handle,CURLOPT_SSL_CIPHER_LIST,"ALL:!aNULL:!LOW:!EXPORT:!SSLv2");
 313     // Verification of the peer is via TrustEngine only.
 314     curl_easy_setopt(handle,CURLOPT_SSL_VERIFYPEER,0);
 315     curl_easy_setopt(handle,CURLOPT_CAINFO,nullptr);
 316     curl_easy_setopt(handle,CURLOPT_HEADERFUNCTION,&curl_header_hook);
 317     curl_easy_setopt(handle,CURLOPT_WRITEFUNCTION,&curl_write_hook);
 318     curl_easy_setopt(handle,CURLOPT_DEBUGFUNCTION,&curl_debug_hook);
 319
 320     return handle;
 321 }
 322
 323 void CURLPool::put(const char* from, const char* to, const char* endpoint, CURL* handle)
 324 {
 325     string key(endpoint);
 326     if (from)
 327         key = key + '|' + from;
 328     if (to)
 329         key = key + '|' + to;
 330     m_lock->lock();
 331     poolmap_t::iterator i=m_bindingMap.find(key);
 332     if (i==m_bindingMap.end())
 333         m_pools.push_front(&(m_bindingMap.insert(poolmap_t::value_type(key,vector<CURL*>(1,handle))).first->second));
 334     else
 335         i->second.push_back(handle);
 336
 337     CURL* killit=nullptr;
 338     if (++m_size > 256) {
 339         // Kick a handle out from the back of the bus.
 340         while (true) {
 341             vector<CURL*>* corpse=m_pools.back();
 342             if (!corpse->empty()) {
 343                 killit=corpse->back();
 344                 corpse->pop_back();
 345                 m_size--;
 346                 break;
 347             }
 348
 349             // Move an empty pool up to the front so we don't keep hitting it.
 350             m_pools.pop_back();
 351             m_pools.push_front(corpse);
 352         }
 353     }
 354     m_lock->unlock();
 355     if (killit) {
 356         curl_easy_cleanup(killit);
 357 #ifdef _DEBUG
 358         xmltooling::NDC("put");
 359 #endif
 360         m_log.info("conn_pool_max limit reached, dropping an old connection");
 361     }
 362 }
 363
 364 bool CURLSOAPTransport::setAuth(transport_auth_t authType, const char* username, const char* password)
 365 {
 366     if (authType==transport_auth_none) {
 367         if (curl_easy_setopt(m_handle,CURLOPT_HTTPAUTH,0)!=CURLE_OK)
 368             return false;
 369         return (curl_easy_setopt(m_handle,CURLOPT_USERPWD,nullptr)==CURLE_OK);
 370     }
 371     long flag=0;
 372     switch (authType) {
 373         case transport_auth_basic:    flag = CURLAUTH_BASIC; break;
 374         case transport_auth_digest:   flag = CURLAUTH_DIGEST; break;
 375         case transport_auth_ntlm:     flag = CURLAUTH_NTLM; break;
 376         case transport_auth_gss:      flag = CURLAUTH_GSSNEGOTIATE; break;
 377         default:            return false;
 378     }
 379     if (curl_easy_setopt(m_handle,CURLOPT_HTTPAUTH,flag)!=CURLE_OK)
 380         return false;
 381     m_simplecreds = string(username ? username : "") + ':' + (password ? password : "");
 382     return (curl_easy_setopt(m_handle,CURLOPT_USERPWD,m_simplecreds.c_str())==CURLE_OK);
 383 }
 384
 385 bool CURLSOAPTransport::setProviderOption(const char* provider, const char* option, const char* value)
 386 {
 387     if (!provider || !option || !value) {
 388         return false;
 389     }
 390     else if (!strcmp(provider, "OpenSSL")) {
 391         if (!strcmp(option, "SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION") && (*value=='1' || *value=='t')) {
 392             // If the new option to enable buggy rengotiation is available, set it.
 393             // Otherwise, signal false if this is newer than 0.9.8k, because that
 394             // means it's 0.9.8l, which blocks renegotiation, and therefore will
 395             // not honor this request. Older versions are buggy, so behave as though
 396             // the flag was set anyway, so we signal true.
 397 #if defined(SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
 398             m_openssl_ops |= SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION;
 399             return true;
 400 #elif (OPENSSL_VERSION_NUMBER > 0x009080bfL)
 401             return false;
 402 #else
 403             return true;
 404 #endif
 405         }
 406         return false;
 407     }
 408     else if (strcmp(provider, "CURL")) {
 409         return false;
 410     }
 411
 412     // For libcurl, the option is an enum and the value type depends on the option.
 413     CURLoption opt = static_cast<CURLoption>(strtol(option, nullptr, 10));
 414     if (opt < CURLOPTTYPE_OBJECTPOINT)
 415         return (curl_easy_setopt(m_handle, opt, strtol(value, nullptr, 10)) == CURLE_OK);
 416 #ifdef CURLOPTTYPE_OFF_T
 417     else if (opt < CURLOPTTYPE_OFF_T) {
 418         if (value)
 419             m_saved_options.push_back(value);
 420         return (curl_easy_setopt(m_handle, opt, value ? m_saved_options.back().c_str() : nullptr) == CURLE_OK);
 421     }
 422 # ifdef HAVE_CURL_OFF_T
 423     else if (sizeof(curl_off_t) == sizeof(long))
 424         return (curl_easy_setopt(m_handle, opt, strtol(value, nullptr, 10)) == CURLE_OK);
 425 # else
 426     else if (sizeof(off_t) == sizeof(long))
 427         return (curl_easy_setopt(m_handle, opt, strtol(value, nullptr, 10)) == CURLE_OK);
 428 # endif
 429     return false;
 430 #else
 431     else {
 432         if (value)
 433             m_saved_options.push_back(value);
 434         return (curl_easy_setopt(m_handle, opt, value ? m_saved_options.back().c_str() : nullptr) == CURLE_OK);
 435     }
 436 #endif
 437 }
 438
 439 const vector<string>& CURLSOAPTransport::getResponseHeader(const char* name) const
 440 {
 441     static vector<string> emptyVector;
 442
 443     map<string,vector<string> >::const_iterator i=m_response_headers.find(name);
 444     if (i!=m_response_headers.end())
 445         return i->second;
 446
 447     for (map<string,vector<string> >::const_iterator j=m_response_headers.begin(); j!=m_response_headers.end(); j++) {
 448 #ifdef HAVE_STRCASECMP
 449         if (!strcasecmp(j->first.c_str(), name))
 450 #else
 451         if (!stricmp(j->first.c_str(), name))
 452 #endif
 453             return j->second;
 454     }
 455
 456     return emptyVector;
 457 }
 458
 459 string CURLSOAPTransport::getContentType() const
 460 {
 461     char* content_type=nullptr;
 462     curl_easy_getinfo(m_handle,CURLINFO_CONTENT_TYPE,&content_type);
 463     return content_type ? content_type : "";
 464 }
 465
 466 long CURLSOAPTransport::getStatusCode() const
 467 {
 468     long code=200;
 469     if (curl_easy_getinfo(m_handle, CURLINFO_RESPONSE_CODE, &code) != CURLE_OK)
 470         code = 200;
 471     return code;
 472 }
 473
 474 void CURLSOAPTransport::send(istream* in)
 475 {
 476 #ifdef _DEBUG
 477     xmltooling::NDC ndc("send");
 478 #endif
 479     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".SOAPTransport.CURL");
 480     Category& log_curl=Category::getInstance(XMLTOOLING_LOGCAT".libcurl");
 481
 482     // For this implementation, it's sufficient to check for https as a sign of transport security.
 483     if (m_mandatory && !isConfidential())
 484         throw IOException("Blocking unprotected HTTP request, transport authentication by server required.");
 485
 486     string msg;
 487
 488     // By this time, the handle has been prepared with the URL to use and the
 489     // caller should have executed any set functions to manipulate it.
 490
 491     // Setup standard per-call curl properties.
 492     curl_easy_setopt(m_handle,CURLOPT_DEBUGDATA,&log_curl);
 493     curl_easy_setopt(m_handle,CURLOPT_FILE,&m_stream);
 494     if (m_chunked && in) {
 495         curl_easy_setopt(m_handle,CURLOPT_POST,1);
 496         m_headers=curl_slist_append(m_headers,"Transfer-Encoding: chunked");
 497         curl_easy_setopt(m_handle,CURLOPT_READFUNCTION,&curl_read_hook);
 498         curl_easy_setopt(m_handle,CURLOPT_READDATA,in);
 499     }
 500     else if (in) {
 501         char buf[1024];
 502         while (*in) {
 503             in->read(buf,1024);
 504             msg.append(buf,in->gcount());
 505         }
 506         curl_easy_setopt(m_handle,CURLOPT_POST,1);
 507         curl_easy_setopt(m_handle,CURLOPT_READFUNCTION,nullptr);
 508         curl_easy_setopt(m_handle,CURLOPT_POSTFIELDS,msg.c_str());
 509         curl_easy_setopt(m_handle,CURLOPT_POSTFIELDSIZE,msg.length());
 510     }
 511     else {
 512         curl_easy_setopt(m_handle,CURLOPT_HTTPGET,1);
 513         curl_easy_setopt(m_handle,CURLOPT_FOLLOWLOCATION,1);
 514         curl_easy_setopt(m_handle,CURLOPT_MAXREDIRS,6);
 515     }
 516
 517     char curl_errorbuf[CURL_ERROR_SIZE];
 518     curl_errorbuf[0]=0;
 519     curl_easy_setopt(m_handle,CURLOPT_ERRORBUFFER,curl_errorbuf);
 520     if (log_curl.isDebugEnabled())
 521         curl_easy_setopt(m_handle,CURLOPT_VERBOSE,1);
 522
 523     // Check for cache tag.
 524     if (m_cacheTag && !m_cacheTag->empty()) {
 525         string hdr("If-None-Match: ");
 526         hdr += *m_cacheTag;
 527         m_headers = curl_slist_append(m_headers, hdr.c_str());
 528     }
 529
 530     // Set request headers.
 531     curl_easy_setopt(m_handle,CURLOPT_HTTPHEADER,m_headers);
 532
 533 #ifndef XMLTOOLING_NO_XMLSEC
 534     if (m_ssl_callback || m_cred || m_trustEngine) {
 535 #else
 536     if (m_ssl_callback) {
 537 #endif
 538         curl_easy_setopt(m_handle,CURLOPT_SSL_CTX_FUNCTION,xml_ssl_ctx_callback);
 539         curl_easy_setopt(m_handle,CURLOPT_SSL_CTX_DATA,this);
 540
 541         // Restore security "state". Necessary because the callback only runs
 542         // when handshakes occur. Even new TCP connections won't execute it.
 543         char* priv=nullptr;
 544         curl_easy_getinfo(m_handle,CURLINFO_PRIVATE,&priv);
 545         if (priv)
 546             m_authenticated=true;
 547     }
 548     else {
 549         curl_easy_setopt(m_handle,CURLOPT_SSL_CTX_FUNCTION,nullptr);
 550         curl_easy_setopt(m_handle,CURLOPT_SSL_CTX_DATA,nullptr);
 551     }
 552
 553     // Make the call.
 554     log.debug("sending SOAP message to %s", m_endpoint.c_str());
 555     if (curl_easy_perform(m_handle) != CURLE_OK) {
 556         throw IOException(
 557             string("CURLSOAPTransport failed while contacting SOAP endpoint (") + m_endpoint + "): " +
 558                 (curl_errorbuf[0] ? curl_errorbuf : "no further information available"));
 559     }
 560
 561     // Check for outgoing cache tag.
 562     if (m_cacheTag) {
 563         const vector<string>& tags = getResponseHeader("ETag");
 564         if (!tags.empty())
 565             *m_cacheTag = tags.front();
 566     }
 567 }
 568
 569 // callback to buffer headers from server
 570 size_t xmltooling::curl_header_hook(void* ptr, size_t size, size_t nmemb, void* stream)
 571 {
 572     // only handle single-byte data
 573     if (size!=1)
 574         return 0;
 575     CURLSOAPTransport* ctx = reinterpret_cast<CURLSOAPTransport*>(stream);
 576     char* buf = (char*)malloc(nmemb + 1);
 577     if (buf) {
 578         memset(buf,0,nmemb + 1);
 579         memcpy(buf,ptr,nmemb);
 580         char* sep=(char*)strchr(buf,':');
 581         if (sep) {
 582             *(sep++)=0;
 583             while (*sep==' ')
 584                 *(sep++)=0;
 585             char* white=buf+nmemb-1;
 586             while (isspace(*white))
 587                 *(white--)=0;
 588             ctx->m_response_headers[buf].push_back(sep);
 589         }
 590         free(buf);
 591         return nmemb;
 592     }
 593     return 0;
 594 }
 595
 596 // callback to send data to server
 597 size_t xmltooling::curl_read_hook(void* ptr, size_t size, size_t nmemb, void* stream)
 598 {
 599     // stream is actually an istream pointer
 600     istream* buf=reinterpret_cast<istream*>(stream);
 601     buf->read(reinterpret_cast<char*>(ptr),size*nmemb);
 602     return buf->gcount();
 603 }
 604
 605 // callback to buffer data from server
 606 size_t xmltooling::curl_write_hook(void* ptr, size_t size, size_t nmemb, void* stream)
 607 {
 608     size_t len = size*nmemb;
 609     reinterpret_cast<stringstream*>(stream)->write(reinterpret_cast<const char*>(ptr),len);
 610     return len;
 611 }
 612
 613 // callback for curl debug data
 614 int xmltooling::curl_debug_hook(CURL* handle, curl_infotype type, char* data, size_t len, void* ptr)
 615 {
 616     // *ptr is actually a logging object
 617     if (!ptr) return 0;
 618     CategoryStream log=reinterpret_cast<Category*>(ptr)->debugStream();
 619     for (unsigned char* ch=(unsigned char*)data; len && (isprint(*ch) || isspace(*ch)); len--)
 620         log << *ch++;
 621     return 0;
 622 }
 623
 624 #ifndef XMLTOOLING_NO_XMLSEC
 625 int xmltooling::verify_callback(X509_STORE_CTX* x509_ctx, void* arg)
 626 {
 627     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".SOAPTransport.CURL");
 628     log.debug("invoking custom X.509 verify callback");
 629 #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
 630     CURLSOAPTransport* ctx = reinterpret_cast<CURLSOAPTransport*>(arg);
 631 #else
 632     // Yes, this sucks. I'd use TLS, but there's no really obvious spot to put the thread key
 633     // and global variables suck too. We can't access the X509_STORE_CTX depth directly because
 634     // OpenSSL only copies it into the context if it's >=0, and the unsigned pointer may be
 635     // negative in the SSL structure's int member.
 636     CURLSOAPTransport* ctx = reinterpret_cast<CURLSOAPTransport*>(
 637         SSL_get_verify_depth(
 638             reinterpret_cast<SSL*>(X509_STORE_CTX_get_ex_data(x509_ctx,SSL_get_ex_data_X509_STORE_CTX_idx()))
 639             )
 640         );
 641 #endif
 642
 643     bool success=false;
 644     if (ctx->m_criteria) {
 645         ctx->m_criteria->setUsage(Credential::TLS_CREDENTIAL);
 646         // Bypass name check (handled for us by curl).
 647         ctx->m_criteria->setPeerName(nullptr);
 648         success = ctx->m_trustEngine->validate(x509_ctx->cert,x509_ctx->untrusted,*(ctx->m_peerResolver),ctx->m_criteria);
 649     }
 650     else {
 651         // Bypass name check (handled for us by curl).
 652         CredentialCriteria cc;
 653         cc.setUsage(Credential::TLS_CREDENTIAL);
 654         success = ctx->m_trustEngine->validate(x509_ctx->cert,x509_ctx->untrusted,*(ctx->m_peerResolver),&cc);
 655     }
 656
 657     if (!success) {
 658         log.error("supplied TrustEngine failed to validate SSL/TLS server certificate");
 659         x509_ctx->error=X509_V_ERR_APPLICATION_VERIFICATION;     // generic error, check log for plugin specifics
 660         ctx->setAuthenticated(false);
 661         return ctx->m_mandatory ? 0 : 1;
 662     }
 663
 664     // Signal success. Hopefully it doesn't matter what's actually in the structure now.
 665     ctx->setAuthenticated(true);
 666     return 1;
 667 }
 668 #endif
 669
 670 // callback to invoke a caller-defined SSL callback
 671 CURLcode xmltooling::xml_ssl_ctx_callback(CURL* curl, SSL_CTX* ssl_ctx, void* userptr)
 672 {
 673     CURLSOAPTransport* conf = reinterpret_cast<CURLSOAPTransport*>(userptr);
 674
 675     // Default flags manually disable SSLv2 so we're not dependent on libcurl to do it.
 676     // Also disable the ticket option where implemented, since this breaks a variety
 677     // of servers. Newer libcurl also does this for us.
 678 #ifdef SSL_OP_NO_TICKET
 679     SSL_CTX_set_options(ssl_ctx, conf->m_openssl_ops|SSL_OP_NO_TICKET);
 680 #else
 681     SSL_CTX_set_options(ssl_ctx, conf->m_openssl_ops);
 682 #endif
 683
 684 #ifndef XMLTOOLING_NO_XMLSEC
 685     if (conf->m_cred)
 686         conf->m_cred->attach(ssl_ctx);
 687
 688     if (conf->m_trustEngine) {
 689         SSL_CTX_set_verify(ssl_ctx,SSL_VERIFY_PEER,nullptr);
 690 #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
 691         // With 0.9.7, we can pass a callback argument directly.
 692         SSL_CTX_set_cert_verify_callback(ssl_ctx,verify_callback,userptr);
 693 #else
 694         // With 0.9.6, there's no argument, so we're going to use a really embarrassing hack and
 695         // stuff the argument in the depth property where it will get copied to the context object
 696         // that's handed to the callback.
 697         SSL_CTX_set_cert_verify_callback(ssl_ctx,reinterpret_cast<int (*)()>(verify_callback),nullptr);
 698         SSL_CTX_set_verify_depth(ssl_ctx,reinterpret_cast<int>(userptr));
 699 #endif
 700     }
 701 #endif
 702
 703     if (conf->m_ssl_callback && !conf->m_ssl_callback(conf, ssl_ctx, conf->m_ssl_userptr))
 704         return CURLE_SSL_CERTPROBLEM;
 705
 706     return CURLE_OK;
 707 }