src/filter_http_rewrite.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) Index Data
   3
   4 Metaproxy is free software; you can redistribute it and/or modify it under
   5 the terms of the GNU General Public License as published by the Free
   6 Software Foundation; either version 2, or (at your option) any later
   7 version.
   8
   9 Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
  10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19 #include "config.hpp"
  20 #include <metaproxy/filter.hpp>
  21 #include <metaproxy/package.hpp>
  22 #include <metaproxy/util.hpp>
  23 #include "filter_http_rewrite.hpp"
  24 #include "html_parser.hpp"
  25
  26 #include <yaz/zgdu.h>
  27 #include <yaz/log.h>
  28
  29 #include <stack>
  30 #include <boost/regex.hpp>
  31 #include <boost/lexical_cast.hpp>
  32 #include <boost/algorithm/string.hpp>
  33
  34 #include <map>
  35
  36 namespace mp = metaproxy_1;
  37 namespace yf = mp::filter;
  38
  39 namespace metaproxy_1 {
  40     namespace filter {
  41         class HttpRewrite::Replace {
  42         public:
  43             bool start_anchor;
  44             boost::regex re;
  45             std::string recipe;
  46             std::map<int, std::string> group_index;
  47             std::string sub_vars(
  48                 const std::map<std::string, std::string> & vars) const;
  49             void parse_groups(std::string pattern);
  50         };
  51
  52         class HttpRewrite::Rule {
  53         public:
  54             std::list<Replace> replace_list;
  55             bool test_patterns(
  56                 std::map<std::string, std::string> &vars,
  57                 std::string &txt, bool anchor,
  58                 std::list<boost::regex> &skip_list);
  59         };
  60         class HttpRewrite::Within {
  61         public:
  62             boost::regex header;
  63             boost::regex attr;
  64             boost::regex tag;
  65             std::string type;
  66             bool reqline;
  67             RulePtr rule;
  68             bool exec(std::map<std::string, std::string> &vars,
  69                       std::string &txt, bool anchor,
  70                       std::list<boost::regex> &skip_list) const;
  71         };
  72
  73         class HttpRewrite::Content {
  74         public:
  75             std::string type;
  76             boost::regex content_re;
  77             std::list<Within> within_list;
  78             void configure(const xmlNode *ptr,
  79                            std::map<std::string, RulePtr > &rules);
  80             void quoted_literal(std::string &content,
  81                                 std::map<std::string, std::string> &vars,
  82                                 std::list<boost::regex> & skip_list) const;
  83             void parse(int verbose, std::string &content,
  84                        std::map<std::string, std::string> & vars,
  85                        std::list<boost::regex> & skip_list ) const;
  86         };
  87         class HttpRewrite::Phase {
  88         public:
  89             Phase();
  90             int m_verbose;
  91             std::list<Content> content_list;
  92             void read_skip_headers(Z_HTTP_Request *hreq,
  93                                    std::list<boost::regex> &skip_list);
  94             void rewrite_reqline(mp::odr & o, Z_HTTP_Request *hreq,
  95                 std::map<std::string, std::string> & vars) const;
  96             void rewrite_headers(mp::odr & o, Z_HTTP_Header *headers,
  97                 std::map<std::string, std::string> & vars) const;
  98             void rewrite_body(mp::odr & o,
  99                               const char *content_type,
 100                               char **content_buf, int *content_len,
 101                               std::map<std::string, std::string> & vars,
 102                               std::list<boost::regex> & skip_list ) const;
 103         };
 104         class HttpRewrite::Event : public HTMLParserEvent {
 105             void openTagStart(const char *tag, int tag_len);
 106             void anyTagEnd(const char *tag, int tag_len, int close_it);
 107             void attribute(const char *tag, int tag_len,
 108                            const char *attr, int attr_len,
 109                            const char *value, int val_len,
 110                            const char *sep);
 111             void closeTag(const char *tag, int tag_len);
 112             void text(const char *value, int len);
 113             const Content *m_content;
 114             WRBUF m_w;
 115             std::stack<std::list<Within>::const_iterator> s_within;
 116             std::map<std::string, std::string> &m_vars;
 117             std::list<boost::regex> & m_skips;
 118         public:
 119             Event(const Content *p,
 120                   std::map<std::string, std::string> &vars,
 121                   std::list<boost::regex> & skip_list );
 122             ~Event();
 123             const char *result();
 124         };
 125     }
 126 }
 127
 128 yf::HttpRewrite::HttpRewrite() :
 129     req_phase(new Phase), res_phase(new Phase)
 130 {
 131 }
 132
 133 yf::HttpRewrite::~HttpRewrite()
 134 {
 135 }
 136
 137 void yf::HttpRewrite::process(mp::Package & package) const
 138 {
 139     yaz_log(YLOG_LOG, "HttpRewrite begins....");
 140     Z_GDU *gdu = package.request().get();
 141     //map of request/response vars
 142     std::map<std::string, std::string> vars;
 143     //we have an http req
 144
 145     std::list<boost::regex> skip_list;
 146
 147     if (gdu && gdu->which == Z_GDU_HTTP_Request)
 148     {
 149         Z_HTTP_Request *hreq = gdu->u.HTTP_Request;
 150         mp::odr o;
 151         req_phase->rewrite_reqline(o, hreq, vars);
 152         res_phase->read_skip_headers(hreq, skip_list);
 153         yaz_log(YLOG_LOG, ">> Request headers");
 154         req_phase->rewrite_headers(o, hreq->headers, vars);
 155         req_phase->rewrite_body(o,
 156                                 z_HTTP_header_lookup(hreq->headers,
 157                                                      "Content-Type"),
 158                                 &hreq->content_buf, &hreq->content_len,
 159                                 vars, skip_list);
 160         package.request() = gdu;
 161     }
 162     package.move();
 163     gdu = package.response().get();
 164     if (gdu && gdu->which == Z_GDU_HTTP_Response)
 165     {
 166         Z_HTTP_Response *hres = gdu->u.HTTP_Response;
 167         yaz_log(YLOG_LOG, "Response code %d", hres->code);
 168         mp::odr o;
 169         yaz_log(YLOG_LOG, "<< Respose headers");
 170         res_phase->rewrite_headers(o, hres->headers, vars);
 171         res_phase->rewrite_body(o,
 172                                 z_HTTP_header_lookup(hres->headers,
 173                                                      "Content-Type"),
 174                                 &hres->content_buf, &hres->content_len,
 175                                 vars, skip_list);
 176         package.response() = gdu;
 177     }
 178 }
 179
 180 // Read (and remove) the X-Metaproxy-SkipLink headers
 181 void yf::HttpRewrite::Phase::read_skip_headers(Z_HTTP_Request *hreq,
 182                                  std::list<boost::regex> &skip_list )
 183 {
 184     std::string url(hreq->path);
 185     if ( url.substr(0,7) != "http://" )
 186     { // path was relative, as it usually is
 187         const char *host =  z_HTTP_header_lookup(hreq->headers, "Host");
 188         if (host)
 189           url = "http://" + std::string(host) + hreq->path ;
 190     }
 191
 192     while ( const char *hv = z_HTTP_header_remove( &(hreq->headers),
 193         "X-Metaproxy-SkipLink") )
 194     {
 195         yaz_log(YLOG_LOG,"Found SkipLink '%s'", hv );
 196         const char *p = strchr(hv,' ');
 197         if (!p)
 198             continue; // should not happen
 199         std::string page(hv,p);
 200         std::string link(p+1);
 201         boost::regex pagere(page);
 202         if ( boost::regex_search(url, pagere) )
 203         {
 204             yaz_log(YLOG_LOG,"SkipLink '%s' matches URL %s",
 205                     page.c_str(), url.c_str() );
 206             boost::regex linkre(link);
 207             skip_list.push_back(linkre);
 208         }
 209         else
 210         {
 211             yaz_log(YLOG_LOG,"SkipLink ignored, '%s' does not match '%s'",
 212                     url.c_str(), page.c_str() );
 213         }
 214     }
 215 }
 216
 217
 218 void yf::HttpRewrite::Phase::rewrite_reqline (mp::odr & o,
 219         Z_HTTP_Request *hreq,
 220         std::map<std::string, std::string> & vars) const
 221 {
 222     //rewrite the request line
 223     std::string path;
 224     if (strstr(hreq->path, "http://") == hreq->path)
 225     {
 226         yaz_log(YLOG_LOG, "Path in the method line is absolute, "
 227             "possibly a proxy request");
 228         path += hreq->path;
 229     }
 230     else
 231     {
 232         //TODO what about proto
 233         const char *host = z_HTTP_header_lookup(hreq->headers, "Host");
 234         if (!host)
 235             return;
 236
 237         path += "http://";
 238         path += host;
 239         path += hreq->path;
 240     }
 241
 242     std::list<Content>::const_iterator cit = content_list.begin();
 243     for (; cit != content_list.end(); cit++)
 244         if (cit->type == "headers")
 245             break;
 246
 247     if (cit == content_list.end())
 248         return;
 249
 250     std::list<Within>::const_iterator it = cit->within_list.begin();
 251     for (; it != cit->within_list.end(); it++)
 252         if (it->reqline)
 253         {
 254             yaz_log(YLOG_LOG, "Proxy request URL is %s", path.c_str());
 255             std::list<boost::regex> dummy_skip_list; // no skips here!
 256             if (it->exec(vars, path, true, dummy_skip_list))
 257             {
 258                 yaz_log(YLOG_LOG, "Rewritten request URL is %s", path.c_str());
 259                 hreq->path = odr_strdup(o, path.c_str());
 260             }
 261         }
 262 }
 263
 264 void yf::HttpRewrite::Phase::rewrite_headers(mp::odr & o,
 265         Z_HTTP_Header *headers,
 266         std::map<std::string, std::string> & vars ) const
 267 {
 268     std::list<Content>::const_iterator cit = content_list.begin();
 269     for (; cit != content_list.end(); cit++)
 270         if (cit->type == "headers")
 271             break;
 272
 273     if (cit == content_list.end())
 274         return;
 275
 276     for (Z_HTTP_Header *header = headers; header; header = header->next)
 277     {
 278         std::list<Within>::const_iterator it = cit->within_list.begin();
 279         for (; it != cit->within_list.end(); it++)
 280         {
 281             if (!it->header.empty() &&
 282                 regex_match(header->name, it->header))
 283             {
 284                 // Match and replace only the header value
 285                 std::string hval(header->value);
 286                 std::list<boost::regex> dummy_skip_list; // no skips here!
 287                 if (it->exec(vars, hval, true, dummy_skip_list))
 288                 {
 289                     header->value = odr_strdup(o, hval.c_str());
 290                 }
 291             }
 292         }
 293     }
 294 }
 295
 296 void yf::HttpRewrite::Phase::rewrite_body(
 297     mp::odr &o,
 298     const char *content_type,
 299     char **content_buf,
 300     int *content_len,
 301     std::map<std::string, std::string> & vars,
 302     std::list<boost::regex> & skip_list ) const
 303 {
 304     if (*content_len == 0)
 305         return;
 306     if (!content_type) {
 307         yaz_log(YLOG_LOG, "rewrite_body: null content_type, can not rewrite");
 308         return;
 309     }
 310     std::list<Content>::const_iterator cit = content_list.begin();
 311     for (; cit != content_list.end(); cit++)
 312     {
 313         yaz_log(YLOG_LOG, "rewrite_body: content_type=%s type=%s",
 314                 content_type, cit->type.c_str());
 315         if (cit->type != "headers"
 316             && regex_match(content_type, cit->content_re))
 317             break;
 318     }
 319     if (cit == content_list.end()) {
 320         yaz_log(YLOG_LOG,"rewrite_body: No content rule matched %s, not rewriting",
 321                 content_type );
 322         return;
 323     }
 324
 325     int i;
 326     for (i = 0; i < *content_len; i++)
 327         if ((*content_buf)[i] == 0) {
 328             yaz_log(YLOG_LOG,"rewrite_body: Looks like binary stuff, not rewriting");
 329             return;  // binary content. skip
 330         }
 331
 332     std::string content(*content_buf, *content_len);
 333     cit->parse(m_verbose, content, vars, skip_list);
 334     *content_buf = odr_strdup(o, content.c_str());
 335     *content_len = strlen(*content_buf);
 336 }
 337
 338 yf::HttpRewrite::Event::Event(const Content *p,
 339                               std::map<std::string, std::string> & vars,
 340                               std::list<boost::regex> & skip_list
 341     ) : m_content(p), m_vars(vars), m_skips(skip_list)
 342 {
 343     m_w = wrbuf_alloc();
 344 }
 345
 346 yf::HttpRewrite::Event::~Event()
 347 {
 348     wrbuf_destroy(m_w);
 349 }
 350
 351 const char *yf::HttpRewrite::Event::result()
 352 {
 353     return wrbuf_cstr(m_w);
 354 }
 355
 356 void yf::HttpRewrite::Event::openTagStart(const char *tag, int tag_len)
 357 {
 358     wrbuf_putc(m_w, '<');
 359     wrbuf_write(m_w, tag, tag_len);
 360
 361     std::string t(tag, tag_len);
 362     std::list<Within>::const_iterator it = m_content->within_list.begin();
 363     for (; it != m_content->within_list.end(); it++)
 364     {
 365         if (!it->tag.empty() && regex_match(t, it->tag))
 366         {
 367             if (!it->attr.empty() && regex_match("#text", it->attr))
 368             {
 369                 s_within.push(it);
 370                 return;
 371             }
 372         }
 373     }
 374 }
 375
 376 void yf::HttpRewrite::Event::anyTagEnd(const char *tag, int tag_len,
 377                                        int close_it)
 378 {
 379     if (close_it)
 380     {
 381         if (!s_within.empty())
 382         {
 383             std::list<Within>::const_iterator it = s_within.top();
 384             std::string t(tag, tag_len);
 385             if (regex_match(t, it->tag))
 386                 s_within.pop();
 387         }
 388     }
 389     if (close_it)
 390         wrbuf_putc(m_w, '/');
 391     wrbuf_putc(m_w, '>');
 392 }
 393
 394 void yf::HttpRewrite::Event::attribute(const char *tag, int tag_len,
 395                                        const char *attr, int attr_len,
 396                                        const char *value, int val_len,
 397                                        const char *sep)
 398 {
 399     std::list<Within>::const_iterator it = m_content->within_list.begin();
 400     bool subst = false;
 401
 402     for (; it != m_content->within_list.end(); it++)
 403     {
 404         std::string t(tag, tag_len);
 405         if (it->tag.empty() || regex_match(t, it->tag))
 406         {
 407             std::string a(attr, attr_len);
 408             if (!it->attr.empty() && regex_match(a, it->attr))
 409                 subst = true;
 410         }
 411         if (subst)
 412             break;
 413     }
 414
 415     wrbuf_putc(m_w, ' ');
 416     wrbuf_write(m_w, attr, attr_len);
 417     if (value)
 418     {
 419         wrbuf_puts(m_w, "=");
 420         wrbuf_puts(m_w, sep);
 421
 422         std::string output;
 423         if (subst)
 424         {
 425             std::string s(value, val_len);
 426             it->exec(m_vars, s, true, m_skips);
 427             wrbuf_puts(m_w, s.c_str());
 428         }
 429         else
 430             wrbuf_write(m_w, value, val_len);
 431         wrbuf_puts(m_w, sep);
 432     }
 433 }
 434
 435 void yf::HttpRewrite::Event::closeTag(const char *tag, int tag_len)
 436 {
 437     if (!s_within.empty())
 438     {
 439         std::list<Within>::const_iterator it = s_within.top();
 440         std::string t(tag, tag_len);
 441         if (regex_match(t, it->tag))
 442             s_within.pop();
 443     }
 444     wrbuf_puts(m_w, "</");
 445     wrbuf_write(m_w, tag, tag_len);
 446 }
 447
 448 void yf::HttpRewrite::Event::text(const char *value, int len)
 449 {
 450     std::list<Within>::const_iterator it = m_content->within_list.end();
 451     if (!s_within.empty())
 452         it = s_within.top();
 453     if (it != m_content->within_list.end())
 454     {
 455         std::string s(value, len);
 456         it->exec(m_vars, s, false, m_skips);
 457         wrbuf_puts(m_w, s.c_str());
 458     }
 459     else
 460         wrbuf_write(m_w, value, len);
 461 }
 462
 463 static bool embed_quoted_literal(
 464     std::string &content,
 465     std::map<std::string, std::string> &vars,
 466     mp::filter::HttpRewrite::RulePtr ruleptr,
 467     bool html_context,
 468     std::list<boost::regex> &skip_list)
 469 {
 470     bool replace = false;
 471     std::string res;
 472     const char *cp = content.c_str();
 473     const char *cp0 = cp;
 474     while (*cp)
 475     {
 476         if (html_context && !strncmp(cp, "&quot;", 6))
 477         {
 478             cp += 6;
 479             res.append(cp0, cp - cp0);
 480             cp0 = cp;
 481             while (*cp)
 482             {
 483                 if (!strncmp(cp, "&quot;", 6))
 484                     break;
 485                 if (*cp == '\n')
 486                     break;
 487                 cp++;
 488             }
 489             if (!*cp)
 490                 break;
 491             std::string s(cp0, cp - cp0);
 492             if (ruleptr->test_patterns(vars, s, true, skip_list))
 493                 replace = true;
 494             cp0 = cp;
 495             res.append(s);
 496         }
 497         else if (*cp == '"' || *cp == '\'')
 498         {
 499             int m = *cp;
 500             cp++;
 501             res.append(cp0, cp - cp0);
 502             cp0 = cp;
 503             while (*cp)
 504             {
 505                 if (cp[-1] != '\\' && *cp == m)
 506                     break;
 507                 if (*cp == '\n')
 508                     break;
 509                 cp++;
 510             }
 511             if (!*cp)
 512                 break;
 513             std::string s(cp0, cp - cp0);
 514             if (ruleptr->test_patterns(vars, s, true, skip_list))
 515                 replace = true;
 516             cp0 = cp;
 517             res.append(s);
 518         }
 519         else if (*cp == '/' && cp[1] == '/')
 520         {
 521             while (cp[1] && cp[1] != '\n')
 522                 cp++;
 523         }
 524         cp++;
 525     }
 526     res.append(cp0, cp - cp0);
 527     content = res;
 528     return replace;
 529 }
 530
 531 bool yf::HttpRewrite::Within::exec(
 532     std::map<std::string, std::string> & vars,
 533     std::string & txt, bool anchor,
 534     std::list<boost::regex> & skip_list) const
 535 {
 536     if (type == "quoted-literal")
 537     {
 538         return embed_quoted_literal(txt, vars, rule, true, skip_list);
 539     }
 540     else
 541     {
 542         return rule->test_patterns(vars, txt, anchor, skip_list);
 543     }
 544 }
 545
 546 bool yf::HttpRewrite::Rule::test_patterns(
 547     std::map<std::string, std::string> & vars,
 548     std::string & txt, bool anchor,
 549     std::list<boost::regex> & skip_list )
 550 {
 551     bool replaces = false;
 552     bool first = anchor;
 553     std::string out;
 554     std::string::const_iterator start, end;
 555     start = txt.begin();
 556     end = txt.end();
 557     while (1)
 558     {
 559         std::list<Replace>::iterator bit = replace_list.end();
 560         boost::smatch bwhat;
 561         bool match_one = false;
 562         {
 563             std::list<Replace>::iterator it = replace_list.begin();
 564             for (; it != replace_list.end(); it++)
 565             {
 566                 if (it->start_anchor && !first)
 567                     continue;
 568                 boost::smatch what;
 569                 if (regex_search(start, end, what, it->re))
 570                 {
 571                     if (!match_one || what[0].first < bwhat[0].first)
 572                     {
 573                         bwhat = what;
 574                         bit = it;
 575                     }
 576                     match_one = true;
 577                 }
 578             }
 579             if (!match_one)
 580                 break;
 581         }
 582         first = false;
 583         replaces = true;
 584         size_t i;
 585         for (i = 1; i < bwhat.size(); ++i)
 586         {
 587             //check if the group is named
 588             std::map<int, std::string>::const_iterator git
 589                 = bit->group_index.find(i);
 590             if (git != bit->group_index.end())
 591             {   //it is
 592                 vars[git->second] = bwhat[i];
 593             }
 594
 595         }
 596         // Compare against skip_list
 597         bool skipthis = false;
 598         std::list<boost::regex>::iterator si = skip_list.begin();
 599         for ( ; si != skip_list.end(); si++) {
 600             if ( boost::regex_search(bwhat.str(0), *si) )
 601             {
 602                 skipthis = true;
 603                 break;
 604             }
 605         }
 606         //prepare replacement string
 607         std::string rvalue = bit->sub_vars(vars);
 608         out.append(start, bwhat[0].first);
 609         if ( skipthis )
 610         {
 611             yaz_log(YLOG_LOG,"! Not rewriting '%s', skiplist match",
 612                     bwhat.str(0).c_str() );
 613             out.append(bwhat.str(0).c_str());
 614         }
 615         else
 616         {
 617             yaz_log(YLOG_LOG, "! Rewritten '%s' to '%s'",
 618                     bwhat.str(0).c_str(), rvalue.c_str());
 619             out.append(rvalue);
 620         }
 621         start = bwhat[0].second; //move search forward
 622     }
 623     out.append(start, end);
 624     txt = out;
 625     return replaces;
 626 }
 627
 628 void yf::HttpRewrite::Replace::parse_groups(std::string pattern)
 629 {
 630     int gnum = 0;
 631     bool esc = false;
 632     const std::string &str = pattern;
 633     std::string res;
 634     start_anchor = str[0] == '^';
 635     yaz_log(YLOG_LOG, "Parsing groups from '%s'", str.c_str());
 636     for (size_t i = 0; i < str.size(); ++i)
 637     {
 638         res += str[i];
 639         if (!esc && str[i] == '\\')
 640         {
 641             esc = true;
 642             continue;
 643         }
 644         if (!esc && str[i] == '(') //group starts
 645         {
 646             gnum++;
 647             if (i+1 < str.size() && str[i+1] == '?') //group with attrs
 648             {
 649                 i++;
 650                 if (i+1 < str.size() && str[i+1] == ':') //non-capturing
 651                 {
 652                     if (gnum > 0) gnum--;
 653                     res += str[i];
 654                     i++;
 655                     res += str[i];
 656                     continue;
 657                 }
 658                 if (i+1 < str.size() && str[i+1] == 'P') //optional, python
 659                     i++;
 660                 if (i+1 < str.size() && str[i+1] == '<') //named
 661                 {
 662                     i++;
 663                     std::string gname;
 664                     bool term = false;
 665                     while (++i < str.size())
 666                     {
 667                         if (str[i] == '>') { term = true; break; }
 668                         if (!isalnum(str[i]))
 669                             throw mp::filter::FilterException
 670                                 ("Only alphanumeric chars allowed, found "
 671                                  " in '"
 672                                  + str
 673                                  + "' at "
 674                                  + boost::lexical_cast<std::string>(i));
 675                         gname += str[i];
 676                     }
 677                     if (!term)
 678                         throw mp::filter::FilterException
 679                             ("Unterminated group name '" + gname
 680                              + " in '" + str +"'");
 681                     group_index[gnum] = gname;
 682                     yaz_log(YLOG_LOG, "Found named group '%s' at $%d",
 683                             gname.c_str(), gnum);
 684                 }
 685             }
 686         }
 687         esc = false;
 688     }
 689     re = res;
 690 }
 691
 692 std::string yf::HttpRewrite::Replace::sub_vars(
 693     const std::map<std::string, std::string> & vars) const
 694 {
 695     std::string out;
 696     bool esc = false;
 697     const std::string & in = recipe;
 698     for (size_t i = 0; i < in.size(); ++i)
 699     {
 700         if (!esc && in[i] == '\\')
 701         {
 702             esc = true;
 703             continue;
 704         }
 705         if (!esc && in[i] == '$') //var
 706         {
 707             if (i+1 < in.size() && in[i+1] == '{') //ref prefix
 708             {
 709                 ++i;
 710                 std::string name;
 711                 bool term = false;
 712                 while (++i < in.size())
 713                 {
 714                     if (in[i] == '}') { term = true; break; }
 715                     name += in[i];
 716                 }
 717                 if (!term) throw mp::filter::FilterException
 718                     ("Unterminated var ref in '"+in+"' at "
 719                      + boost::lexical_cast<std::string>(i));
 720                 std::map<std::string, std::string>::const_iterator it
 721                     = vars.find(name);
 722                 if (it != vars.end())
 723                 {
 724                     out += it->second;
 725                 }
 726             }
 727             else
 728             {
 729                 throw mp::filter::FilterException
 730                     ("Malformed or trimmed var ref in '"
 731                      +in+"' at "+boost::lexical_cast<std::string>(i));
 732             }
 733             continue;
 734         }
 735         //passthru
 736         out += in[i];
 737         esc = false;
 738     }
 739     return out;
 740 }
 741
 742 yf::HttpRewrite::Phase::Phase() : m_verbose(0)
 743 {
 744 }
 745
 746 void yf::HttpRewrite::Content::parse(
 747     int verbose,
 748     std::string &content,
 749     std::map<std::string, std::string> &vars,
 750     std::list<boost::regex> & skip_list ) const
 751 {
 752     if (type == "html")
 753     {
 754         HTMLParser parser;
 755         Event ev(this, vars, skip_list);
 756
 757         parser.set_verbose(verbose);
 758
 759         parser.parse(ev, content.c_str());
 760         content = ev.result();
 761     }
 762     if (type == "quoted-literal")
 763     {
 764         quoted_literal(content, vars, skip_list);
 765     }
 766 }
 767
 768 void yf::HttpRewrite::Content::quoted_literal(
 769     std::string &content,
 770     std::map<std::string, std::string> &vars,
 771     std::list<boost::regex> & skip_list ) const
 772 {
 773     std::list<Within>::const_iterator it = within_list.begin();
 774     if (it != within_list.end())
 775         embed_quoted_literal(content, vars, it->rule, false, skip_list);
 776 }
 777
 778 void yf::HttpRewrite::Content::configure(
 779     const xmlNode *ptr, std::map<std::string, RulePtr > &rules)
 780 {
 781     for (; ptr; ptr = ptr->next)
 782     {
 783         if (ptr->type != XML_ELEMENT_NODE)
 784             continue;
 785         if (!strcmp((const char *) ptr->name, "within"))
 786         {
 787             static const char *names[7] =
 788                 { "header", "attr", "tag", "rule", "reqline", "type", 0 };
 789             std::string values[6];
 790             mp::xml::parse_attr(ptr, names, values);
 791             Within w;
 792             if (values[0].length() > 0)
 793                 w.header.assign(values[0], boost::regex_constants::icase);
 794             if (values[1].length() > 0)
 795                 w.attr.assign(values[1], boost::regex_constants::icase);
 796             if (values[2].length() > 0)
 797                 w.tag.assign(values[2], boost::regex_constants::icase);
 798
 799             std::vector<std::string> rulenames;
 800             boost::split(rulenames, values[3], boost::is_any_of(","));
 801             if (rulenames.size() == 0)
 802             {
 803                 throw mp::filter::FilterException
 804                     ("Empty rule in '" + values[3] +
 805                      "' in http_rewrite filter");
 806             }
 807             else if (rulenames.size() == 1)
 808             {
 809                 std::map<std::string,RulePtr>::const_iterator it =
 810                     rules.find(rulenames[0]);
 811                 if (it == rules.end())
 812                     throw mp::filter::FilterException
 813                         ("Reference to non-existing rule '" + rulenames[0] +
 814                          "' in http_rewrite filter");
 815                 w.rule = it->second;
 816
 817             }
 818             else
 819             {
 820                 RulePtr rule(new Rule);
 821                 size_t i;
 822                 for (i = 0; i < rulenames.size(); i++)
 823                 {
 824                     std::map<std::string,RulePtr>::const_iterator it =
 825                         rules.find(rulenames[i]);
 826                     if (it == rules.end())
 827                         throw mp::filter::FilterException
 828                             ("Reference to non-existing rule '" + rulenames[i] +
 829                              "' in http_rewrite filter");
 830                     RulePtr subRule = it->second;
 831                     std::list<Replace>::iterator rit =
 832                         subRule->replace_list.begin();
 833                     for (; rit != subRule->replace_list.end(); rit++)
 834                         rule->replace_list.push_back(*rit);
 835                 }
 836                 w.rule = rule;
 837             }
 838             w.reqline = values[4] == "1";
 839             w.type = values[5];
 840             if (w.type.empty() || w.type == "quoted-literal")
 841                 ;
 842             else
 843                 throw mp::filter::FilterException
 844                     ("within type must be quoted-literal or none in "
 845                      " in http_rewrite filter");
 846             within_list.push_back(w);
 847         }
 848     }
 849 }
 850
 851 void yf::HttpRewrite::configure_phase(const xmlNode *ptr, Phase &phase)
 852 {
 853     static const char *names[2] = { "verbose", 0 };
 854     std::string values[1];
 855     values[0] = "0";
 856     mp::xml::parse_attr(ptr, names, values);
 857
 858     phase.m_verbose = atoi(values[0].c_str());
 859
 860     std::map<std::string, RulePtr > rules;
 861     for (ptr = ptr->children; ptr; ptr = ptr->next)
 862     {
 863         if (ptr->type != XML_ELEMENT_NODE)
 864             continue;
 865         else if (!strcmp((const char *) ptr->name, "rule"))
 866         {
 867             static const char *names[2] = { "name", 0 };
 868             std::string values[1];
 869             values[0] = "default";
 870             mp::xml::parse_attr(ptr, names, values);
 871
 872             RulePtr rule(new Rule);
 873             for (xmlNode *p = ptr->children; p; p = p->next)
 874             {
 875                 if (p->type != XML_ELEMENT_NODE)
 876                     continue;
 877                 if (!strcmp((const char *) p->name, "rewrite"))
 878                 {
 879                     Replace replace;
 880                     std::string from;
 881                     const struct _xmlAttr *attr;
 882                     for (attr = p->properties; attr; attr = attr->next)
 883                     {
 884                         if (!strcmp((const char *) attr->name,  "from"))
 885                             from = mp::xml::get_text(attr->children);
 886                         else if (!strcmp((const char *) attr->name,  "to"))
 887                             replace.recipe = mp::xml::get_text(attr->children);
 888                         else
 889                             throw mp::filter::FilterException
 890                                 ("Bad attribute "
 891                                  + std::string((const char *) attr->name)
 892                                  + " in rewrite section of http_rewrite");
 893                     }
 894                     yaz_log(YLOG_LOG, "Found rewrite rule from '%s' to '%s'",
 895                             from.c_str(), replace.recipe.c_str());
 896                     if (!from.empty())
 897                     {
 898                         replace.parse_groups(from);
 899                         rule->replace_list.push_back(replace);
 900                     }
 901                 }
 902                 else
 903                     throw mp::filter::FilterException
 904                         ("Bad element "
 905                          + std::string((const char *) p->name)
 906                          + " in http_rewrite filter");
 907             }
 908             rules[values[0]] = rule;
 909         }
 910         else if (!strcmp((const char *) ptr->name, "content"))
 911         {
 912             static const char *names[3] =
 913                 { "type", "mime", 0 };
 914             std::string values[2];
 915             mp::xml::parse_attr(ptr, names, values);
 916             if (values[0].empty())
 917             {
 918                     throw mp::filter::FilterException
 919                         ("Missing attribute, type for for element "
 920                          + std::string((const char *) ptr->name)
 921                          + " in http_rewrite filter");
 922             }
 923             Content c;
 924
 925             c.type = values[0];
 926             if (!values[1].empty())
 927                 c.content_re.assign(values[1], boost::regex::icase);
 928             c.configure(ptr->children, rules);
 929             phase.content_list.push_back(c);
 930         }
 931         else
 932         {
 933             throw mp::filter::FilterException
 934                 ("Bad element "
 935                  + std::string((const char *) ptr->name)
 936                  + " in http_rewrite filter");
 937         }
 938     }
 939 }
 940
 941 void yf::HttpRewrite::configure(const xmlNode * ptr, bool test_only,
 942         const char *path)
 943 {
 944     for (ptr = ptr->children; ptr; ptr = ptr->next)
 945     {
 946         if (ptr->type != XML_ELEMENT_NODE)
 947             continue;
 948         else if (!strcmp((const char *) ptr->name, "request"))
 949         {
 950             configure_phase(ptr, *req_phase);
 951         }
 952         else if (!strcmp((const char *) ptr->name, "response"))
 953         {
 954             configure_phase(ptr, *res_phase);
 955         }
 956         else
 957         {
 958             throw mp::filter::FilterException
 959                 ("Bad element "
 960                  + std::string((const char *) ptr->name)
 961                  + " in http_rewrite1 filter");
 962         }
 963     }
 964 }
 965
 966 static mp::filter::Base* filter_creator()
 967 {
 968     return new mp::filter::HttpRewrite;
 969 }
 970
 971 extern "C" {
 972     struct metaproxy_1_filter_struct metaproxy_1_filter_http_rewrite = {
 973         0,
 974         "http_rewrite",
 975         filter_creator
 976     };
 977 }
 978
 979
 980 /*
 981  * Local variables:
 982  * c-basic-offset: 4
 983  * c-file-style: "Stroustrup"
 984  * indent-tabs-mode: nil
 985  * End:
 986  * vim: shiftwidth=4 tabstop=8 expandtab
 987  */
 988