src/filter_http_rewrite.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2013 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         };
  59         class HttpRewrite::Within {
  60         public:
  61             boost::regex header;
  62             boost::regex attr;
  63             boost::regex tag;
  64             std::string type;
  65             bool reqline;
  66             RulePtr rule;
  67             bool exec(std::map<std::string, std::string> &vars,
  68                       std::string &txt, bool anchor) const;
  69         };
  70
  71         class HttpRewrite::Content {
  72         public:
  73             std::string type;
  74             boost::regex content_re;
  75             std::list<Within> within_list;
  76             void configure(const xmlNode *ptr,
  77                            std::map<std::string, RulePtr > &rules);
  78             void quoted_literal(std::string &content,
  79                                 std::map<std::string, std::string> &vars) const;
  80             void parse(int verbose, std::string &content,
  81                        std::map<std::string, std::string> & vars) const;
  82         };
  83         class HttpRewrite::Phase {
  84         public:
  85             Phase();
  86             int m_verbose;
  87             std::list<Content> content_list;
  88             void rewrite_reqline(mp::odr & o, Z_HTTP_Request *hreq,
  89                 std::map<std::string, std::string> & vars) const;
  90             void rewrite_headers(mp::odr & o, Z_HTTP_Header *headers,
  91                 std::map<std::string, std::string> & vars) const;
  92             void rewrite_body(mp::odr & o,
  93                               const char *content_type,
  94                               char **content_buf, int *content_len,
  95                               std::map<std::string, std::string> & vars) const;
  96         };
  97         class HttpRewrite::Event : public HTMLParserEvent {
  98             void openTagStart(const char *tag, int tag_len);
  99             void anyTagEnd(const char *tag, int tag_len, int close_it);
 100             void attribute(const char *tag, int tag_len,
 101                            const char *attr, int attr_len,
 102                            const char *value, int val_len,
 103                            const char *sep);
 104             void closeTag(const char *tag, int tag_len);
 105             void text(const char *value, int len);
 106             const Content *m_content;
 107             WRBUF m_w;
 108             std::stack<std::list<Within>::const_iterator> s_within;
 109             std::map<std::string, std::string> &m_vars;
 110         public:
 111             Event(const Content *p, std::map<std::string, std::string> &vars);
 112             ~Event();
 113             const char *result();
 114         };
 115     }
 116 }
 117
 118 yf::HttpRewrite::HttpRewrite() :
 119     req_phase(new Phase), res_phase(new Phase)
 120 {
 121 }
 122
 123 yf::HttpRewrite::~HttpRewrite()
 124 {
 125 }
 126
 127 void yf::HttpRewrite::process(mp::Package & package) const
 128 {
 129     yaz_log(YLOG_LOG, "HttpRewrite begins....");
 130     Z_GDU *gdu = package.request().get();
 131     //map of request/response vars
 132     std::map<std::string, std::string> vars;
 133     //we have an http req
 134     if (gdu && gdu->which == Z_GDU_HTTP_Request)
 135     {
 136         Z_HTTP_Request *hreq = gdu->u.HTTP_Request;
 137         mp::odr o;
 138         req_phase->rewrite_reqline(o, hreq, vars);
 139         yaz_log(YLOG_LOG, ">> Request headers");
 140         req_phase->rewrite_headers(o, hreq->headers, vars);
 141         req_phase->rewrite_body(o,
 142                                 z_HTTP_header_lookup(hreq->headers,
 143                                                      "Content-Type"),
 144                                 &hreq->content_buf, &hreq->content_len,
 145                                 vars);
 146         package.request() = gdu;
 147     }
 148     package.move();
 149     gdu = package.response().get();
 150     if (gdu && gdu->which == Z_GDU_HTTP_Response)
 151     {
 152         Z_HTTP_Response *hres = gdu->u.HTTP_Response;
 153         yaz_log(YLOG_LOG, "Response code %d", hres->code);
 154         mp::odr o;
 155         yaz_log(YLOG_LOG, "<< Respose headers");
 156         res_phase->rewrite_headers(o, hres->headers, vars);
 157         res_phase->rewrite_body(o,
 158                                 z_HTTP_header_lookup(hres->headers,
 159                                                      "Content-Type"),
 160                                 &hres->content_buf, &hres->content_len,
 161                                 vars);
 162         package.response() = gdu;
 163     }
 164 }
 165
 166 void yf::HttpRewrite::Phase::rewrite_reqline (mp::odr & o,
 167         Z_HTTP_Request *hreq,
 168         std::map<std::string, std::string> & vars) const
 169 {
 170     //rewrite the request line
 171     std::string path;
 172     if (strstr(hreq->path, "http://") == hreq->path)
 173     {
 174         yaz_log(YLOG_LOG, "Path in the method line is absolute, "
 175             "possibly a proxy request");
 176         path += hreq->path;
 177     }
 178     else
 179     {
 180         //TODO what about proto
 181         const char *host = z_HTTP_header_lookup(hreq->headers, "Host");
 182         if (!host)
 183             return;
 184
 185         path += "http://";
 186         path += host;
 187         path += hreq->path;
 188     }
 189
 190     std::list<Content>::const_iterator cit = content_list.begin();
 191     for (; cit != content_list.end(); cit++)
 192         if (cit->type == "headers")
 193             break;
 194
 195     if (cit == content_list.end())
 196         return;
 197
 198     std::list<Within>::const_iterator it = cit->within_list.begin();
 199     for (; it != cit->within_list.end(); it++)
 200         if (it->reqline)
 201         {
 202             yaz_log(YLOG_LOG, "Proxy request URL is %s", path.c_str());
 203             if (it->exec(vars, path, true))
 204             {
 205                 yaz_log(YLOG_LOG, "Rewritten request URL is %s", path.c_str());
 206                 hreq->path = odr_strdup(o, path.c_str());
 207             }
 208         }
 209 }
 210
 211 void yf::HttpRewrite::Phase::rewrite_headers(mp::odr & o,
 212         Z_HTTP_Header *headers,
 213         std::map<std::string, std::string> & vars) const
 214 {
 215     std::list<Content>::const_iterator cit = content_list.begin();
 216     for (; cit != content_list.end(); cit++)
 217         if (cit->type == "headers")
 218             break;
 219
 220     if (cit == content_list.end())
 221         return;
 222
 223     for (Z_HTTP_Header *header = headers; header; header = header->next)
 224     {
 225         std::list<Within>::const_iterator it = cit->within_list.begin();
 226         for (; it != cit->within_list.end(); it++)
 227         {
 228             if (!it->header.empty() &&
 229                 regex_match(header->name, it->header))
 230             {
 231                 // Match and replace only the header value
 232                 std::string hval(header->value);
 233                 if (it->exec(vars, hval, true))
 234                 {
 235                     header->value = odr_strdup(o, hval.c_str());
 236                 }
 237             }
 238         }
 239     }
 240 }
 241
 242 void yf::HttpRewrite::Phase::rewrite_body(
 243     mp::odr &o,
 244     const char *content_type,
 245     char **content_buf,
 246     int *content_len,
 247     std::map<std::string, std::string> & vars) const
 248 {
 249     if (*content_len == 0)
 250         return;
 251     if (!content_type) {
 252         yaz_log(YLOG_LOG, "rewrite_body: null content_type, can not rewrite");
 253         return;
 254     }
 255     std::list<Content>::const_iterator cit = content_list.begin();
 256     for (; cit != content_list.end(); cit++)
 257     {
 258         yaz_log(YLOG_LOG, "rewrite_body: content_type=%s type=%s",
 259                 content_type, cit->type.c_str());
 260         if (cit->type != "headers"
 261             && regex_match(content_type, cit->content_re))
 262             break;
 263     }
 264     if (cit == content_list.end()) {
 265         yaz_log(YLOG_LOG,"rewrite_body: No content rule matched %s, not rewriting",
 266                 content_type );
 267         return;
 268     }
 269
 270     int i;
 271     for (i = 0; i < *content_len; i++)
 272         if ((*content_buf)[i] == 0) {
 273             yaz_log(YLOG_LOG,"rewrite_body: Looks like binary stuff, not rewriting");
 274             return;  // binary content. skip
 275         }
 276
 277     std::string content(*content_buf, *content_len);
 278     cit->parse(m_verbose, content, vars);
 279     *content_buf = odr_strdup(o, content.c_str());
 280     *content_len = strlen(*content_buf);
 281 }
 282
 283 yf::HttpRewrite::Event::Event(const Content *p,
 284                               std::map<std::string, std::string> & vars
 285     ) : m_content(p), m_vars(vars)
 286 {
 287     m_w = wrbuf_alloc();
 288 }
 289
 290 yf::HttpRewrite::Event::~Event()
 291 {
 292     wrbuf_destroy(m_w);
 293 }
 294
 295 const char *yf::HttpRewrite::Event::result()
 296 {
 297     return wrbuf_cstr(m_w);
 298 }
 299
 300 void yf::HttpRewrite::Event::openTagStart(const char *tag, int tag_len)
 301 {
 302     wrbuf_putc(m_w, '<');
 303     wrbuf_write(m_w, tag, tag_len);
 304
 305     std::string t(tag, tag_len);
 306     std::list<Within>::const_iterator it = m_content->within_list.begin();
 307     for (; it != m_content->within_list.end(); it++)
 308     {
 309         if (!it->tag.empty() && regex_match(t, it->tag))
 310         {
 311             if (!it->attr.empty() && regex_match("#text", it->attr))
 312             {
 313                 s_within.push(it);
 314                 return;
 315             }
 316         }
 317     }
 318 }
 319
 320 void yf::HttpRewrite::Event::anyTagEnd(const char *tag, int tag_len,
 321                                        int close_it)
 322 {
 323     if (close_it)
 324     {
 325         if (!s_within.empty())
 326         {
 327             std::list<Within>::const_iterator it = s_within.top();
 328             std::string t(tag, tag_len);
 329             if (regex_match(t, it->tag))
 330                 s_within.pop();
 331         }
 332     }
 333     if (close_it)
 334         wrbuf_putc(m_w, '/');
 335     wrbuf_putc(m_w, '>');
 336 }
 337
 338 void yf::HttpRewrite::Event::attribute(const char *tag, int tag_len,
 339                                        const char *attr, int attr_len,
 340                                        const char *value, int val_len,
 341                                        const char *sep)
 342 {
 343     std::list<Within>::const_iterator it = m_content->within_list.begin();
 344     bool subst = false;
 345
 346     for (; it != m_content->within_list.end(); it++)
 347     {
 348         std::string t(tag, tag_len);
 349         if (it->tag.empty() || regex_match(t, it->tag))
 350         {
 351             std::string a(attr, attr_len);
 352             if (!it->attr.empty() && regex_match(a, it->attr))
 353                 subst = true;
 354         }
 355         if (subst)
 356             break;
 357     }
 358
 359     wrbuf_putc(m_w, ' ');
 360     wrbuf_write(m_w, attr, attr_len);
 361     if (value)
 362     {
 363         wrbuf_puts(m_w, "=");
 364         wrbuf_puts(m_w, sep);
 365
 366         std::string output;
 367         if (subst)
 368         {
 369             std::string s(value, val_len);
 370             it->exec(m_vars, s, true);
 371             wrbuf_puts(m_w, s.c_str());
 372         }
 373         else
 374             wrbuf_write(m_w, value, val_len);
 375         wrbuf_puts(m_w, sep);
 376     }
 377 }
 378
 379 void yf::HttpRewrite::Event::closeTag(const char *tag, int tag_len)
 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     wrbuf_puts(m_w, "</");
 389     wrbuf_write(m_w, tag, tag_len);
 390 }
 391
 392 void yf::HttpRewrite::Event::text(const char *value, int len)
 393 {
 394     std::list<Within>::const_iterator it = m_content->within_list.end();
 395     if (!s_within.empty())
 396         it = s_within.top();
 397     if (it != m_content->within_list.end())
 398     {
 399         std::string s(value, len);
 400         it->exec(m_vars, s, false);
 401         wrbuf_puts(m_w, s.c_str());
 402     }
 403     else
 404         wrbuf_write(m_w, value, len);
 405 }
 406
 407 static bool embed_quoted_literal(
 408     std::string &content,
 409     std::map<std::string, std::string> &vars,
 410     mp::filter::HttpRewrite::RulePtr ruleptr,
 411     bool html_context)
 412 {
 413     bool replace = false;
 414     std::string res;
 415     const char *cp = content.c_str();
 416     const char *cp0 = cp;
 417     while (*cp)
 418     {
 419         if (html_context && !strncmp(cp, "&quot;", 6))
 420         {
 421             cp += 6;
 422             res.append(cp0, cp - cp0);
 423             cp0 = cp;
 424             while (*cp)
 425             {
 426                 if (!strncmp(cp, "&quot;", 6))
 427                     break;
 428                 if (*cp == '\n')
 429                     break;
 430                 cp++;
 431             }
 432             if (!*cp)
 433                 break;
 434             std::string s(cp0, cp - cp0);
 435             if (ruleptr->test_patterns(vars, s, true))
 436                 replace = true;
 437             cp0 = cp;
 438             res.append(s);
 439         }
 440         else if (*cp == '"' || *cp == '\'')
 441         {
 442             int m = *cp;
 443             cp++;
 444             res.append(cp0, cp - cp0);
 445             cp0 = cp;
 446             while (*cp)
 447             {
 448                 if (cp[-1] != '\\' && *cp == m)
 449                     break;
 450                 if (*cp == '\n')
 451                     break;
 452                 cp++;
 453             }
 454             if (!*cp)
 455                 break;
 456             std::string s(cp0, cp - cp0);
 457             if (ruleptr->test_patterns(vars, s, true))
 458                 replace = true;
 459             cp0 = cp;
 460             res.append(s);
 461         }
 462         else if (*cp == '/' && cp[1] == '/')
 463         {
 464             while (cp[1] && cp[1] != '\n')
 465                 cp++;
 466         }
 467         cp++;
 468     }
 469     res.append(cp0, cp - cp0);
 470     content = res;
 471     return replace;
 472 }
 473
 474 bool yf::HttpRewrite::Within::exec(
 475     std::map<std::string, std::string> & vars,
 476     std::string & txt, bool anchor) const
 477 {
 478     if (type == "quoted-literal")
 479     {
 480         return embed_quoted_literal(txt, vars, rule, true);
 481     }
 482     else
 483     {
 484         return rule->test_patterns(vars, txt, anchor);
 485     }
 486 }
 487
 488 bool yf::HttpRewrite::Rule::test_patterns(
 489     std::map<std::string, std::string> & vars,
 490     std::string & txt, bool anchor)
 491 {
 492     bool replaces = false;
 493     bool first = anchor;
 494     std::string out;
 495     std::string::const_iterator start, end;
 496     start = txt.begin();
 497     end = txt.end();
 498     while (1)
 499     {
 500         std::list<Replace>::iterator bit = replace_list.end();
 501         boost::smatch bwhat;
 502         bool match_one = false;
 503         {
 504             std::list<Replace>::iterator it = replace_list.begin();
 505             for (; it != replace_list.end(); it++)
 506             {
 507                 if (it->start_anchor && !first)
 508                     continue;
 509                 boost::smatch what;
 510                 if (regex_search(start, end, what, it->re))
 511                 {
 512                     if (!match_one || what[0].first < bwhat[0].first)
 513                     {
 514                         bwhat = what;
 515                         bit = it;
 516                     }
 517                     match_one = true;
 518                 }
 519             }
 520             if (!match_one)
 521                 break;
 522         }
 523         first = false;
 524         replaces = true;
 525         size_t i;
 526         for (i = 1; i < bwhat.size(); ++i)
 527         {
 528             //check if the group is named
 529             std::map<int, std::string>::const_iterator git
 530                 = bit->group_index.find(i);
 531             if (git != bit->group_index.end())
 532             {   //it is
 533                 vars[git->second] = bwhat[i];
 534             }
 535
 536         }
 537         //prepare replacement string
 538         std::string rvalue = bit->sub_vars(vars);
 539         yaz_log(YLOG_LOG, "! Rewritten '%s' to '%s'",
 540                 bwhat.str(0).c_str(), rvalue.c_str());
 541         out.append(start, bwhat[0].first);
 542         out.append(rvalue);
 543         start = bwhat[0].second; //move search forward
 544     }
 545     out.append(start, end);
 546     txt = out;
 547     return replaces;
 548 }
 549
 550 void yf::HttpRewrite::Replace::parse_groups(std::string pattern)
 551 {
 552     int gnum = 0;
 553     bool esc = false;
 554     const std::string &str = pattern;
 555     std::string res;
 556     start_anchor = str[0] == '^';
 557     yaz_log(YLOG_LOG, "Parsing groups from '%s'", str.c_str());
 558     for (size_t i = 0; i < str.size(); ++i)
 559     {
 560         res += str[i];
 561         if (!esc && str[i] == '\\')
 562         {
 563             esc = true;
 564             continue;
 565         }
 566         if (!esc && str[i] == '(') //group starts
 567         {
 568             gnum++;
 569             if (i+1 < str.size() && str[i+1] == '?') //group with attrs
 570             {
 571                 i++;
 572                 if (i+1 < str.size() && str[i+1] == ':') //non-capturing
 573                 {
 574                     if (gnum > 0) gnum--;
 575                     res += str[i];
 576                     i++;
 577                     res += str[i];
 578                     continue;
 579                 }
 580                 if (i+1 < str.size() && str[i+1] == 'P') //optional, python
 581                     i++;
 582                 if (i+1 < str.size() && str[i+1] == '<') //named
 583                 {
 584                     i++;
 585                     std::string gname;
 586                     bool term = false;
 587                     while (++i < str.size())
 588                     {
 589                         if (str[i] == '>') { term = true; break; }
 590                         if (!isalnum(str[i]))
 591                             throw mp::filter::FilterException
 592                                 ("Only alphanumeric chars allowed, found "
 593                                  " in '"
 594                                  + str
 595                                  + "' at "
 596                                  + boost::lexical_cast<std::string>(i));
 597                         gname += str[i];
 598                     }
 599                     if (!term)
 600                         throw mp::filter::FilterException
 601                             ("Unterminated group name '" + gname
 602                              + " in '" + str +"'");
 603                     group_index[gnum] = gname;
 604                     yaz_log(YLOG_LOG, "Found named group '%s' at $%d",
 605                             gname.c_str(), gnum);
 606                 }
 607             }
 608         }
 609         esc = false;
 610     }
 611     re = res;
 612 }
 613
 614 std::string yf::HttpRewrite::Replace::sub_vars(
 615     const std::map<std::string, std::string> & vars) const
 616 {
 617     std::string out;
 618     bool esc = false;
 619     const std::string & in = recipe;
 620     for (size_t i = 0; i < in.size(); ++i)
 621     {
 622         if (!esc && in[i] == '\\')
 623         {
 624             esc = true;
 625             continue;
 626         }
 627         if (!esc && in[i] == '$') //var
 628         {
 629             if (i+1 < in.size() && in[i+1] == '{') //ref prefix
 630             {
 631                 ++i;
 632                 std::string name;
 633                 bool term = false;
 634                 while (++i < in.size())
 635                 {
 636                     if (in[i] == '}') { term = true; break; }
 637                     name += in[i];
 638                 }
 639                 if (!term) throw mp::filter::FilterException
 640                     ("Unterminated var ref in '"+in+"' at "
 641                      + boost::lexical_cast<std::string>(i));
 642                 std::map<std::string, std::string>::const_iterator it
 643                     = vars.find(name);
 644                 if (it != vars.end())
 645                 {
 646                     out += it->second;
 647                 }
 648             }
 649             else
 650             {
 651                 throw mp::filter::FilterException
 652                     ("Malformed or trimmed var ref in '"
 653                      +in+"' at "+boost::lexical_cast<std::string>(i));
 654             }
 655             continue;
 656         }
 657         //passthru
 658         out += in[i];
 659         esc = false;
 660     }
 661     return out;
 662 }
 663
 664 yf::HttpRewrite::Phase::Phase() : m_verbose(0)
 665 {
 666 }
 667
 668 void yf::HttpRewrite::Content::parse(
 669     int verbose,
 670     std::string &content,
 671     std::map<std::string, std::string> &vars) const
 672 {
 673     if (type == "html")
 674     {
 675         HTMLParser parser;
 676         Event ev(this, vars);
 677
 678         parser.set_verbose(verbose);
 679
 680         parser.parse(ev, content.c_str());
 681         content = ev.result();
 682     }
 683     if (type == "quoted-literal")
 684     {
 685         quoted_literal(content, vars);
 686     }
 687 }
 688
 689 void yf::HttpRewrite::Content::quoted_literal(
 690     std::string &content,
 691     std::map<std::string, std::string> &vars) const
 692 {
 693     std::list<Within>::const_iterator it = within_list.begin();
 694     if (it != within_list.end())
 695         embed_quoted_literal(content, vars, it->rule, false);
 696 }
 697
 698 void yf::HttpRewrite::Content::configure(
 699     const xmlNode *ptr, std::map<std::string, RulePtr > &rules)
 700 {
 701     for (; ptr; ptr = ptr->next)
 702     {
 703         if (ptr->type != XML_ELEMENT_NODE)
 704             continue;
 705         if (!strcmp((const char *) ptr->name, "within"))
 706         {
 707             static const char *names[7] =
 708                 { "header", "attr", "tag", "rule", "reqline", "type", 0 };
 709             std::string values[6];
 710             mp::xml::parse_attr(ptr, names, values);
 711             Within w;
 712             if (values[0].length() > 0)
 713                 w.header.assign(values[0], boost::regex_constants::icase);
 714             if (values[1].length() > 0)
 715                 w.attr.assign(values[1], boost::regex_constants::icase);
 716             if (values[2].length() > 0)
 717                 w.tag.assign(values[2], boost::regex_constants::icase);
 718
 719             std::vector<std::string> rulenames;
 720             boost::split(rulenames, values[3], boost::is_any_of(","));
 721             if (rulenames.size() == 0)
 722             {
 723                 throw mp::filter::FilterException
 724                     ("Empty rule in '" + values[3] +
 725                      "' in http_rewrite filter");
 726             }
 727             else if (rulenames.size() == 1)
 728             {
 729                 std::map<std::string,RulePtr>::const_iterator it =
 730                     rules.find(rulenames[0]);
 731                 if (it == rules.end())
 732                     throw mp::filter::FilterException
 733                         ("Reference to non-existing rule '" + rulenames[0] +
 734                          "' in http_rewrite filter");
 735                 w.rule = it->second;
 736
 737             }
 738             else
 739             {
 740                 RulePtr rule(new Rule);
 741                 size_t i;
 742                 for (i = 0; i < rulenames.size(); i++)
 743                 {
 744                     std::map<std::string,RulePtr>::const_iterator it =
 745                         rules.find(rulenames[i]);
 746                     if (it == rules.end())
 747                         throw mp::filter::FilterException
 748                             ("Reference to non-existing rule '" + rulenames[i] +
 749                              "' in http_rewrite filter");
 750                     RulePtr subRule = it->second;
 751                     std::list<Replace>::iterator rit =
 752                         subRule->replace_list.begin();
 753                     for (; rit != subRule->replace_list.end(); rit++)
 754                         rule->replace_list.push_back(*rit);
 755                 }
 756                 w.rule = rule;
 757             }
 758             w.reqline = values[4] == "1";
 759             w.type = values[5];
 760             if (w.type.empty() || w.type == "quoted-literal")
 761                 ;
 762             else
 763                 throw mp::filter::FilterException
 764                     ("within type must be quoted-literal or none in "
 765                      " in http_rewrite filter");
 766             within_list.push_back(w);
 767         }
 768     }
 769 }
 770
 771 void yf::HttpRewrite::configure_phase(const xmlNode *ptr, Phase &phase)
 772 {
 773     static const char *names[2] = { "verbose", 0 };
 774     std::string values[1];
 775     values[0] = "0";
 776     mp::xml::parse_attr(ptr, names, values);
 777
 778     phase.m_verbose = atoi(values[0].c_str());
 779
 780     std::map<std::string, RulePtr > rules;
 781     for (ptr = ptr->children; ptr; ptr = ptr->next)
 782     {
 783         if (ptr->type != XML_ELEMENT_NODE)
 784             continue;
 785         else if (!strcmp((const char *) ptr->name, "rule"))
 786         {
 787             static const char *names[2] = { "name", 0 };
 788             std::string values[1];
 789             values[0] = "default";
 790             mp::xml::parse_attr(ptr, names, values);
 791
 792             RulePtr rule(new Rule);
 793             for (xmlNode *p = ptr->children; p; p = p->next)
 794             {
 795                 if (p->type != XML_ELEMENT_NODE)
 796                     continue;
 797                 if (!strcmp((const char *) p->name, "rewrite"))
 798                 {
 799                     Replace replace;
 800                     std::string from;
 801                     const struct _xmlAttr *attr;
 802                     for (attr = p->properties; attr; attr = attr->next)
 803                     {
 804                         if (!strcmp((const char *) attr->name,  "from"))
 805                             from = mp::xml::get_text(attr->children);
 806                         else if (!strcmp((const char *) attr->name,  "to"))
 807                             replace.recipe = mp::xml::get_text(attr->children);
 808                         else
 809                             throw mp::filter::FilterException
 810                                 ("Bad attribute "
 811                                  + std::string((const char *) attr->name)
 812                                  + " in rewrite section of http_rewrite");
 813                     }
 814                     yaz_log(YLOG_LOG, "Found rewrite rule from '%s' to '%s'",
 815                             from.c_str(), replace.recipe.c_str());
 816                     if (!from.empty())
 817                     {
 818                         replace.parse_groups(from);
 819                         rule->replace_list.push_back(replace);
 820                     }
 821                 }
 822                 else
 823                     throw mp::filter::FilterException
 824                         ("Bad element "
 825                          + std::string((const char *) p->name)
 826                          + " in http_rewrite filter");
 827             }
 828             rules[values[0]] = rule;
 829         }
 830         else if (!strcmp((const char *) ptr->name, "content"))
 831         {
 832             static const char *names[3] =
 833                 { "type", "mime", 0 };
 834             std::string values[2];
 835             mp::xml::parse_attr(ptr, names, values);
 836             if (values[0].empty())
 837             {
 838                     throw mp::filter::FilterException
 839                         ("Missing attribute, type for for element "
 840                          + std::string((const char *) ptr->name)
 841                          + " in http_rewrite filter");
 842             }
 843             Content c;
 844
 845             c.type = values[0];
 846             if (!values[1].empty())
 847                 c.content_re.assign(values[1], boost::regex::icase);
 848             c.configure(ptr->children, rules);
 849             phase.content_list.push_back(c);
 850         }
 851         else
 852         {
 853             throw mp::filter::FilterException
 854                 ("Bad element "
 855                  + std::string((const char *) ptr->name)
 856                  + " in http_rewrite filter");
 857         }
 858     }
 859 }
 860
 861 void yf::HttpRewrite::configure(const xmlNode * ptr, bool test_only,
 862         const char *path)
 863 {
 864     for (ptr = ptr->children; ptr; ptr = ptr->next)
 865     {
 866         if (ptr->type != XML_ELEMENT_NODE)
 867             continue;
 868         else if (!strcmp((const char *) ptr->name, "request"))
 869         {
 870             configure_phase(ptr, *req_phase);
 871         }
 872         else if (!strcmp((const char *) ptr->name, "response"))
 873         {
 874             configure_phase(ptr, *res_phase);
 875         }
 876         else
 877         {
 878             throw mp::filter::FilterException
 879                 ("Bad element "
 880                  + std::string((const char *) ptr->name)
 881                  + " in http_rewrite1 filter");
 882         }
 883     }
 884 }
 885
 886 static mp::filter::Base* filter_creator()
 887 {
 888     return new mp::filter::HttpRewrite;
 889 }
 890
 891 extern "C" {
 892     struct metaproxy_1_filter_struct metaproxy_1_filter_http_rewrite = {
 893         0,
 894         "http_rewrite",
 895         filter_creator
 896     };
 897 }
 898
 899
 900 /*
 901  * Local variables:
 902  * c-basic-offset: 4
 903  * c-file-style: "Stroustrup"
 904  * indent-tabs-mode: nil
 905  * End:
 906  * vim: shiftwidth=4 tabstop=8 expandtab
 907  */
 908