src/url.cc

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 23    URL Parsing */
  10
  11 #include "squid.h"
  12 #include "globals.h"
  13 #include "HttpRequest.h"
  14 #include "rfc1738.h"
  15 #include "SquidConfig.h"
  16 #include "SquidString.h"
  17 #include "URL.h"
  18
  19 static HttpRequest *urlParseFinish(const HttpRequestMethod& method,
  20                                    const AnyP::ProtocolType protocol,
  21                                    const char *const urlpath,
  22                                    const char *const host,
  23                                    const SBuf &login,
  24                                    const int port,
  25                                    HttpRequest *request);
  26 static HttpRequest *urnParse(const HttpRequestMethod& method, char *urn, HttpRequest *request);
  27 static const char valid_hostname_chars_u[] =
  28     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  29     "abcdefghijklmnopqrstuvwxyz"
  30     "0123456789-._"
  31     "[:]"
  32     ;
  33 static const char valid_hostname_chars[] =
  34     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  35     "abcdefghijklmnopqrstuvwxyz"
  36     "0123456789-."
  37     "[:]"
  38     ;
  39
  40 const SBuf &
  41 URL::Asterisk()
  42 {
  43     static SBuf star("*");
  44     return star;
  45 }
  46
  47 const SBuf &
  48 URL::SlashPath()
  49 {
  50     static SBuf slash("/");
  51     return slash;
  52 }
  53
  54 void
  55 URL::host(const char *src)
  56 {
  57     hostAddr_.setEmpty();
  58     hostAddr_ = src;
  59     if (hostAddr_.isAnyAddr()) {
  60         xstrncpy(host_, src, sizeof(host_));
  61         hostIsNumeric_ = false;
  62     } else {
  63         hostAddr_.toHostStr(host_, sizeof(host_));
  64         debugs(23, 3, "given IP: " << hostAddr_);
  65         hostIsNumeric_ = 1;
  66     }
  67     touch();
  68 }
  69
  70 const SBuf &
  71 URL::path() const
  72 {
  73     // RFC 3986 section 3.3 says path can be empty (path-abempty).
  74     // RFC 7230 sections 2.7.3, 5.3.1, 5.7.2 - says path cannot be empty, default to "/"
  75     // at least when sending and using. We must still accept path-abempty as input.
  76     if (path_.isEmpty() && (scheme_ == AnyP::PROTO_HTTP || scheme_ == AnyP::PROTO_HTTPS))
  77         return SlashPath();
  78
  79     return path_;
  80 }
  81
  82 void
  83 urlInitialize(void)
  84 {
  85     debugs(23, 5, "urlInitialize: Initializing...");
  86     /* this ensures that the number of protocol strings is the same as
  87      * the enum slots allocated because the last enum is always 'MAX'.
  88      */
  89     assert(strcmp(AnyP::ProtocolType_str[AnyP::PROTO_MAX], "MAX") == 0);
  90     /*
  91      * These test that our matchDomainName() function works the
  92      * way we expect it to.
  93      */
  94     assert(0 == matchDomainName("foo.com", "foo.com"));
  95     assert(0 == matchDomainName(".foo.com", "foo.com"));
  96     assert(0 == matchDomainName("foo.com", ".foo.com"));
  97     assert(0 == matchDomainName(".foo.com", ".foo.com"));
  98     assert(0 == matchDomainName("x.foo.com", ".foo.com"));
  99     assert(0 != matchDomainName("x.foo.com", "foo.com"));
 100     assert(0 != matchDomainName("foo.com", "x.foo.com"));
 101     assert(0 != matchDomainName("bar.com", "foo.com"));
 102     assert(0 != matchDomainName(".bar.com", "foo.com"));
 103     assert(0 != matchDomainName(".bar.com", ".foo.com"));
 104     assert(0 != matchDomainName("bar.com", ".foo.com"));
 105     assert(0 < matchDomainName("zzz.com", "foo.com"));
 106     assert(0 > matchDomainName("aaa.com", "foo.com"));
 107     assert(0 == matchDomainName("FOO.com", "foo.COM"));
 108     assert(0 < matchDomainName("bfoo.com", "afoo.com"));
 109     assert(0 > matchDomainName("afoo.com", "bfoo.com"));
 110     assert(0 < matchDomainName("x-foo.com", ".foo.com"));
 111     /* more cases? */
 112 }
 113
 114 /**
 115  * urlParseProtocol() takes begin (b) and end (e) pointers, but for
 116  * backwards compatibility, e defaults to NULL, in which case we
 117  * assume b is NULL-terminated.
 118  */
 119 AnyP::ProtocolType
 120 urlParseProtocol(const char *b, const char *e)
 121 {
 122     /*
 123      * if e is NULL, b must be NULL terminated and we
 124      * make e point to the first whitespace character
 125      * after b.
 126      */
 127
 128     if (NULL == e)
 129         e = b + strcspn(b, ":");
 130
 131     int len = e - b;
 132
 133     /* test common stuff first */
 134
 135     if (strncasecmp(b, "http", len) == 0)
 136         return AnyP::PROTO_HTTP;
 137
 138     if (strncasecmp(b, "ftp", len) == 0)
 139         return AnyP::PROTO_FTP;
 140
 141     if (strncasecmp(b, "https", len) == 0)
 142         return AnyP::PROTO_HTTPS;
 143
 144     if (strncasecmp(b, "file", len) == 0)
 145         return AnyP::PROTO_FTP;
 146
 147     if (strncasecmp(b, "coap", len) == 0)
 148         return AnyP::PROTO_COAP;
 149
 150     if (strncasecmp(b, "coaps", len) == 0)
 151         return AnyP::PROTO_COAPS;
 152
 153     if (strncasecmp(b, "gopher", len) == 0)
 154         return AnyP::PROTO_GOPHER;
 155
 156     if (strncasecmp(b, "wais", len) == 0)
 157         return AnyP::PROTO_WAIS;
 158
 159     if (strncasecmp(b, "cache_object", len) == 0)
 160         return AnyP::PROTO_CACHE_OBJECT;
 161
 162     if (strncasecmp(b, "urn", len) == 0)
 163         return AnyP::PROTO_URN;
 164
 165     if (strncasecmp(b, "whois", len) == 0)
 166         return AnyP::PROTO_WHOIS;
 167
 168     return AnyP::PROTO_NONE;
 169 }
 170
 171 /*
 172  * Parse a URI/URL.
 173  *
 174  * If the 'request' arg is non-NULL, put parsed values there instead
 175  * of allocating a new HttpRequest.
 176  *
 177  * This abuses HttpRequest as a way of representing the parsed url
 178  * and its components.
 179  * method is used to switch parsers and to init the HttpRequest.
 180  * If method is Http::METHOD_CONNECT, then rather than a URL a hostname:port is
 181  * looked for.
 182  * The url is non const so that if its too long we can NULL-terminate it in place.
 183  */
 184
 185 /*
 186  * This routine parses a URL. Its assumed that the URL is complete -
 187  * ie, the end of the string is the end of the URL. Don't pass a partial
 188  * URL here as this routine doesn't have any way of knowing whether
 189  * its partial or not (ie, it handles the case of no trailing slash as
 190  * being "end of host with implied path of /".
 191  */
 192 HttpRequest *
 193 urlParse(const HttpRequestMethod& method, char *url, HttpRequest *request)
 194 {
 195     LOCAL_ARRAY(char, proto, MAX_URL);
 196     LOCAL_ARRAY(char, login, MAX_URL);
 197     LOCAL_ARRAY(char, host, MAX_URL);
 198     LOCAL_ARRAY(char, urlpath, MAX_URL);
 199     char *t = NULL;
 200     char *q = NULL;
 201     int port;
 202     AnyP::ProtocolType protocol = AnyP::PROTO_NONE;
 203     int l;
 204     int i;
 205     const char *src;
 206     char *dst;
 207     proto[0] = host[0] = urlpath[0] = login[0] = '\0';
 208
 209     if ((l = strlen(url)) + Config.appendDomainLen > (MAX_URL - 1)) {
 210         /* terminate so it doesn't overflow other buffers */
 211         *(url + (MAX_URL >> 1)) = '\0';
 212         debugs(23, DBG_IMPORTANT, "urlParse: URL too large (" << l << " bytes)");
 213         return NULL;
 214     }
 215     if (method == Http::METHOD_CONNECT) {
 216         port = CONNECT_PORT;
 217
 218         if (sscanf(url, "[%[^]]]:%d", host, &port) < 1)
 219             if (sscanf(url, "%[^:]:%d", host, &port) < 1)
 220                 return NULL;
 221
 222     } else if ((method == Http::METHOD_OPTIONS || method == Http::METHOD_TRACE) &&
 223                URL::Asterisk().cmp(url) == 0) {
 224         protocol = AnyP::PROTO_HTTP;
 225         port = AnyP::UriScheme(protocol).defaultPort();
 226         return urlParseFinish(method, protocol, url, host, SBuf(), port, request);
 227     } else if (!strncmp(url, "urn:", 4)) {
 228         return urnParse(method, url, request);
 229     } else {
 230         /* Parse the URL: */
 231         src = url;
 232         i = 0;
 233         /* Find first : - everything before is protocol */
 234         for (i = 0, dst = proto; i < l && *src != ':'; ++i, ++src, ++dst) {
 235             *dst = *src;
 236         }
 237         if (i >= l)
 238             return NULL;
 239         *dst = '\0';
 240
 241         /* Then its :// */
 242         if ((i+3) > l || *src != ':' || *(src + 1) != '/' || *(src + 2) != '/')
 243             return NULL;
 244         i += 3;
 245         src += 3;
 246
 247         /* Then everything until first /; thats host (and port; which we'll look for here later) */
 248         // bug 1881: If we don't get a "/" then we imply it was there
 249         // bug 3074: We could just be given a "?" or "#". These also imply "/"
 250         // bug 3233: whitespace is also a hostname delimiter.
 251         for (dst = host; i < l && *src != '/' && *src != '?' && *src != '#' && *src != '\0' && !xisspace(*src); ++i, ++src, ++dst) {
 252             *dst = *src;
 253         }
 254
 255         /*
 256          * We can't check for "i >= l" here because we could be at the end of the line
 257          * and have a perfectly valid URL w/ no trailing '/'. In this case we assume we've
 258          * been -given- a valid URL and the path is just '/'.
 259          */
 260         if (i > l)
 261             return NULL;
 262         *dst = '\0';
 263
 264         // bug 3074: received 'path' starting with '?', '#', or '\0' implies '/'
 265         if (*src == '?' || *src == '#' || *src == '\0') {
 266             urlpath[0] = '/';
 267             dst = &urlpath[1];
 268         } else {
 269             dst = urlpath;
 270         }
 271         /* Then everything from / (inclusive) until \r\n or \0 - thats urlpath */
 272         for (; i < l && *src != '\r' && *src != '\n' && *src != '\0'; ++i, ++src, ++dst) {
 273             *dst = *src;
 274         }
 275
 276         /* We -could- be at the end of the buffer here */
 277         if (i > l)
 278             return NULL;
 279         /* If the URL path is empty we set it to be "/" */
 280         if (dst == urlpath) {
 281             *dst = '/';
 282             ++dst;
 283         }
 284         *dst = '\0';
 285
 286         protocol = urlParseProtocol(proto);
 287         port = AnyP::UriScheme(protocol).defaultPort();
 288
 289         /* Is there any login information? (we should eventually parse it above) */
 290         t = strrchr(host, '@');
 291         if (t != NULL) {
 292             strncpy((char *) login, (char *) host, sizeof(login)-1);
 293             login[sizeof(login)-1] = '\0';
 294             t = strrchr(login, '@');
 295             *t = 0;
 296             strncpy((char *) host, t + 1, sizeof(host)-1);
 297             host[sizeof(host)-1] = '\0';
 298         }
 299
 300         /* Is there any host information? (we should eventually parse it above) */
 301         if (*host == '[') {
 302             /* strip any IPA brackets. valid under IPv6. */
 303             dst = host;
 304             /* only for IPv6 sadly, pre-IPv6/URL code can't handle the clean result properly anyway. */
 305             src = host;
 306             ++src;
 307             l = strlen(host);
 308             i = 1;
 309             for (; i < l && *src != ']' && *src != '\0'; ++i, ++src, ++dst) {
 310                 *dst = *src;
 311             }
 312
 313             /* we moved in-place, so truncate the actual hostname found */
 314             *dst = '\0';
 315             ++dst;
 316
 317             /* skip ahead to either start of port, or original EOS */
 318             while (*dst != '\0' && *dst != ':')
 319                 ++dst;
 320             t = dst;
 321         } else {
 322             t = strrchr(host, ':');
 323
 324             if (t != strchr(host,':') ) {
 325                 /* RFC 2732 states IPv6 "SHOULD" be bracketed. allowing for times when its not. */
 326                 /* RFC 3986 'update' simply modifies this to an "is" with no emphasis at all! */
 327                 /* therefore we MUST accept the case where they are not bracketed at all. */
 328                 t = NULL;
 329             }
 330         }
 331
 332         // Bug 3183 sanity check: If scheme is present, host must be too.
 333         if (protocol != AnyP::PROTO_NONE && host[0] == '\0') {
 334             debugs(23, DBG_IMPORTANT, "SECURITY ALERT: Missing hostname in URL '" << url << "'. see access.log for details.");
 335             return NULL;
 336         }
 337
 338         if (t && *t == ':') {
 339             *t = '\0';
 340             ++t;
 341             port = atoi(t);
 342         }
 343     }
 344
 345     for (t = host; *t; ++t)
 346         *t = xtolower(*t);
 347
 348     if (stringHasWhitespace(host)) {
 349         if (URI_WHITESPACE_STRIP == Config.uri_whitespace) {
 350             t = q = host;
 351             while (*t) {
 352                 if (!xisspace(*t)) {
 353                     *q = *t;
 354                     ++q;
 355                 }
 356                 ++t;
 357             }
 358             *q = '\0';
 359         }
 360     }
 361
 362     debugs(23, 3, "urlParse: Split URL '" << url << "' into proto='" << proto << "', host='" << host << "', port='" << port << "', path='" << urlpath << "'");
 363
 364     if (Config.onoff.check_hostnames && strspn(host, Config.onoff.allow_underscore ? valid_hostname_chars_u : valid_hostname_chars) != strlen(host)) {
 365         debugs(23, DBG_IMPORTANT, "urlParse: Illegal character in hostname '" << host << "'");
 366         return NULL;
 367     }
 368
 369     /* For IPV6 addresses also check for a colon */
 370     if (Config.appendDomain && !strchr(host, '.') && !strchr(host, ':'))
 371         strncat(host, Config.appendDomain, SQUIDHOSTNAMELEN - strlen(host) - 1);
 372
 373     /* remove trailing dots from hostnames */
 374     while ((l = strlen(host)) > 0 && host[--l] == '.')
 375         host[l] = '\0';
 376
 377     /* reject duplicate or leading dots */
 378     if (strstr(host, "..") || *host == '.') {
 379         debugs(23, DBG_IMPORTANT, "urlParse: Illegal hostname '" << host << "'");
 380         return NULL;
 381     }
 382
 383     if (port < 1 || port > 65535) {
 384         debugs(23, 3, "urlParse: Invalid port '" << port << "'");
 385         return NULL;
 386     }
 387
 388 #if HARDCODE_DENY_PORTS
 389     /* These ports are filtered in the default squid.conf, but
 390      * maybe someone wants them hardcoded... */
 391     if (port == 7 || port == 9 || port == 19) {
 392         debugs(23, DBG_CRITICAL, "urlParse: Deny access to port " << port);
 393         return NULL;
 394     }
 395 #endif
 396
 397     if (stringHasWhitespace(urlpath)) {
 398         debugs(23, 2, "urlParse: URI has whitespace: {" << url << "}");
 399
 400         switch (Config.uri_whitespace) {
 401
 402         case URI_WHITESPACE_DENY:
 403             return NULL;
 404
 405         case URI_WHITESPACE_ALLOW:
 406             break;
 407
 408         case URI_WHITESPACE_ENCODE:
 409             t = rfc1738_escape_unescaped(urlpath);
 410             xstrncpy(urlpath, t, MAX_URL);
 411             break;
 412
 413         case URI_WHITESPACE_CHOP:
 414             *(urlpath + strcspn(urlpath, w_space)) = '\0';
 415             break;
 416
 417         case URI_WHITESPACE_STRIP:
 418         default:
 419             t = q = urlpath;
 420             while (*t) {
 421                 if (!xisspace(*t)) {
 422                     *q = *t;
 423                     ++q;
 424                 }
 425                 ++t;
 426             }
 427             *q = '\0';
 428         }
 429     }
 430
 431     return urlParseFinish(method, protocol, urlpath, host, SBuf(login), port, request);
 432 }
 433
 434 /**
 435  * Update request with parsed URI data.  If the request arg is
 436  * non-NULL, put parsed values there instead of allocating a new
 437  * HttpRequest.
 438  */
 439 static HttpRequest *
 440 urlParseFinish(const HttpRequestMethod& method,
 441                const AnyP::ProtocolType protocol,
 442                const char *const urlpath,
 443                const char *const host,
 444                const SBuf &login,
 445                const int port,
 446                HttpRequest *request)
 447 {
 448     if (NULL == request)
 449         request = new HttpRequest(method, protocol, urlpath);
 450     else {
 451         request->initHTTP(method, protocol, urlpath);
 452     }
 453
 454     request->url.host(host);
 455     request->url.userInfo(login);
 456     request->url.port(port);
 457     return request;
 458 }
 459
 460 static HttpRequest *
 461 urnParse(const HttpRequestMethod& method, char *urn, HttpRequest *request)
 462 {
 463     debugs(50, 5, "urnParse: " << urn);
 464     if (request) {
 465         request->initHTTP(method, AnyP::PROTO_URN, urn + 4);
 466         return request;
 467     }
 468
 469     return new HttpRequest(method, AnyP::PROTO_URN, urn + 4);
 470 }
 471
 472 void
 473 URL::touch()
 474 {
 475     absolute_.clear();
 476     authorityHttp_.clear();
 477     authorityWithPort_.clear();
 478 }
 479
 480 SBuf &
 481 URL::authority(bool requirePort) const
 482 {
 483     if (authorityHttp_.isEmpty()) {
 484
 485         // both formats contain Host/IP
 486         authorityWithPort_.append(host());
 487         authorityHttp_ = authorityWithPort_;
 488
 489         // authorityForm_ only has :port if it is non-default
 490         authorityWithPort_.appendf(":%u",port());
 491         if (port() != getScheme().defaultPort())
 492             authorityHttp_ = authorityWithPort_;
 493     }
 494
 495     return requirePort ? authorityWithPort_ : authorityHttp_;
 496 }
 497
 498 SBuf &
 499 URL::absolute() const
 500 {
 501     if (absolute_.isEmpty()) {
 502         // TODO: most URL will be much shorter, avoid allocating this much
 503         absolute_.reserveCapacity(MAX_URL);
 504
 505         absolute_.appendf("%s:", getScheme().c_str());
 506         if (getScheme() != AnyP::PROTO_URN) {
 507             absolute_.append("//", 2);
 508             const bool omitUserInfo = getScheme() == AnyP::PROTO_HTTP ||
 509                                       getScheme() != AnyP::PROTO_HTTPS ||
 510                                       userInfo().isEmpty();
 511             if (!omitUserInfo) {
 512                 absolute_.append(userInfo());
 513                 absolute_.append("@", 1);
 514             }
 515             absolute_.append(authority());
 516         }
 517         absolute_.append(path());
 518     }
 519
 520     return absolute_;
 521 }
 522
 523 /** \todo AYJ: Performance: This is an *almost* duplicate of HttpRequest::effectiveRequestUri(). But elides the query-string.
 524  *        After copying it on in the first place! Would be less code to merge the two with a flag parameter.
 525  *        and never copy the query-string part in the first place
 526  */
 527 char *
 528 urlCanonicalClean(const HttpRequest * request)
 529 {
 530     LOCAL_ARRAY(char, buf, MAX_URL);
 531
 532     snprintf(buf, sizeof(buf), SQUIDSBUFPH, SQUIDSBUFPRINT(request->effectiveRequestUri()));
 533     buf[sizeof(buf)-1] = '\0';
 534
 535     // URN, CONNECT method, and non-stripped URIs can go straight out
 536     if (Config.onoff.strip_query_terms && !(request->method == Http::METHOD_CONNECT || request->url.getScheme() == AnyP::PROTO_URN)) {
 537         // strip anything AFTER a question-mark
 538         // leaving the '?' in place
 539         if (auto t = strchr(buf, '?')) {
 540             *(++t) = '\0';
 541         }
 542     }
 543
 544     if (stringHasCntl(buf))
 545         xstrncpy(buf, rfc1738_escape_unescaped(buf), MAX_URL);
 546
 547     return buf;
 548 }
 549
 550 /**
 551  * Yet another alternative to urlCanonical.
 552  * This one adds the https:// parts to Http::METHOD_CONNECT URL
 553  * for use in error page outputs.
 554  * Luckily we can leverage the others instead of duplicating.
 555  */
 556 const char *
 557 urlCanonicalFakeHttps(const HttpRequest * request)
 558 {
 559     LOCAL_ARRAY(char, buf, MAX_URL);
 560
 561     // method CONNECT and port HTTPS
 562     if (request->method == Http::METHOD_CONNECT && request->url.port() == 443) {
 563         snprintf(buf, MAX_URL, "https://%s/*", request->url.host());
 564         return buf;
 565     }
 566
 567     // else do the normal complete canonical thing.
 568     return urlCanonicalClean(request);
 569 }
 570
 571 /*
 572  * Test if a URL is relative.
 573  *
 574  * RFC 2396, Section 5 (Page 17) implies that in a relative URL, a '/' will
 575  * appear before a ':'.
 576  */
 577 bool
 578 urlIsRelative(const char *url)
 579 {
 580     const char *p;
 581
 582     if (url == NULL) {
 583         return (false);
 584     }
 585     if (*url == '\0') {
 586         return (false);
 587     }
 588
 589     for (p = url; *p != '\0' && *p != ':' && *p != '/'; ++p);
 590
 591     if (*p == ':') {
 592         return (false);
 593     }
 594     return (true);
 595 }
 596
 597 /*
 598  * Convert a relative URL to an absolute URL using the context of a given
 599  * request.
 600  *
 601  * It is assumed that you have already ensured that the URL is relative.
 602  *
 603  * If NULL is returned it is an indication that the method in use in the
 604  * request does not distinguish between relative and absolute and you should
 605  * use the url unchanged.
 606  *
 607  * If non-NULL is returned, it is up to the caller to free the resulting
 608  * memory using safe_free().
 609  */
 610 char *
 611 urlMakeAbsolute(const HttpRequest * req, const char *relUrl)
 612 {
 613
 614     if (req->method.id() == Http::METHOD_CONNECT) {
 615         return (NULL);
 616     }
 617
 618     char *urlbuf = (char *)xmalloc(MAX_URL * sizeof(char));
 619
 620     if (req->url.getScheme() == AnyP::PROTO_URN) {
 621         // XXX: this is what the original code did, but it seems to break the
 622         // intended behaviour of this function. It returns the stored URN path,
 623         // not converting the given one into a URN...
 624         snprintf(urlbuf, MAX_URL, SQUIDSBUFPH, SQUIDSBUFPRINT(req->url.absolute()));
 625         return (urlbuf);
 626     }
 627
 628     SBuf authorityForm = req->url.authority(); // host[:port]
 629     size_t urllen = snprintf(urlbuf, MAX_URL, "%s://" SQUIDSBUFPH "%s" SQUIDSBUFPH,
 630                              req->url.getScheme().c_str(),
 631                              SQUIDSBUFPRINT(req->url.userInfo()),
 632                              !req->url.userInfo().isEmpty() ? "@" : "",
 633                              SQUIDSBUFPRINT(authorityForm));
 634
 635     // if the first char is '/' assume its a relative path
 636     // XXX: this breaks on scheme-relative URLs,
 637     // but we should not see those outside ESI, and rarely there.
 638     // XXX: also breaks on any URL containing a '/' in the query-string portion
 639     if (relUrl[0] == '/') {
 640         xstrncpy(&urlbuf[urllen], relUrl, MAX_URL - urllen - 1);
 641     } else {
 642         SBuf path = req->url.path();
 643         SBuf::size_type lastSlashPos = path.rfind('/');
 644
 645         if (lastSlashPos == SBuf::npos) {
 646             // replace the whole path with the given bit(s)
 647             urlbuf[urllen] = '/';
 648             ++urllen;
 649             xstrncpy(&urlbuf[urllen], relUrl, MAX_URL - urllen - 1);
 650         } else {
 651             // replace only the last (file?) segment with the given bit(s)
 652             ++lastSlashPos;
 653             if (lastSlashPos > MAX_URL - urllen - 1) {
 654                 // XXX: crops bits in the middle of the combined URL.
 655                 lastSlashPos = MAX_URL - urllen - 1;
 656             }
 657             xstrncpy(&urlbuf[urllen], path.rawContent(), lastSlashPos);
 658             urllen += lastSlashPos;
 659             if (urllen + 1 < MAX_URL) {
 660                 xstrncpy(&urlbuf[urllen], relUrl, MAX_URL - urllen - 1);
 661             }
 662         }
 663     }
 664
 665     return (urlbuf);
 666 }
 667
 668 int
 669 matchDomainName(const char *h, const char *d, bool honorWildcards)
 670 {
 671     int dl;
 672     int hl;
 673
 674     while ('.' == *h)
 675         ++h;
 676
 677     hl = strlen(h);
 678
 679     dl = strlen(d);
 680
 681     /*
 682      * Start at the ends of the two strings and work towards the
 683      * beginning.
 684      */
 685     while (xtolower(h[--hl]) == xtolower(d[--dl])) {
 686         if (hl == 0 && dl == 0) {
 687             /*
 688              * We made it all the way to the beginning of both
 689              * strings without finding any difference.
 690              */
 691             return 0;
 692         }
 693
 694         if (0 == hl) {
 695             /*
 696              * The host string is shorter than the domain string.
 697              * There is only one case when this can be a match.
 698              * If the domain is just one character longer, and if
 699              * that character is a leading '.' then we call it a
 700              * match.
 701              */
 702
 703             if (1 == dl && '.' == d[0])
 704                 return 0;
 705             else
 706                 return -1;
 707         }
 708
 709         if (0 == dl) {
 710             /*
 711              * The domain string is shorter than the host string.
 712              * This is a match only if the first domain character
 713              * is a leading '.'.
 714              */
 715
 716             if ('.' == d[0])
 717                 return 0;
 718             else
 719                 return 1;
 720         }
 721     }
 722
 723     /*
 724      * We found different characters in the same position (from the end).
 725      */
 726
 727     // If the h has a form of "*.foo.com" and d has a form of "x.foo.com"
 728     // then the h[hl] points to '*', h[hl+1] to '.' and d[dl] to 'x'
 729     // The following checks are safe, the "h[hl + 1]" in the worst case is '\0'.
 730     if (honorWildcards && h[hl] == '*' && h[hl + 1] == '.')
 731         return 0;
 732
 733     /*
 734      * If one of those character is '.' then its special.  In order
 735      * for splay tree sorting to work properly, "x-foo.com" must
 736      * be greater than ".foo.com" even though '-' is less than '.'.
 737      */
 738     if ('.' == d[dl])
 739         return 1;
 740
 741     if ('.' == h[hl])
 742         return -1;
 743
 744     return (xtolower(h[hl]) - xtolower(d[dl]));
 745 }
 746
 747 /*
 748  * return true if we can serve requests for this method.
 749  */
 750 int
 751 urlCheckRequest(const HttpRequest * r)
 752 {
 753     int rc = 0;
 754     /* protocol "independent" methods
 755      *
 756      * actually these methods are specific to HTTP:
 757      * they are methods we recieve on our HTTP port,
 758      * and if we had a FTP listener would not be relevant
 759      * there.
 760      *
 761      * So, we should delegate them to HTTP. The problem is that we
 762      * do not have a default protocol from the client side of HTTP.
 763      */
 764
 765     if (r->method == Http::METHOD_CONNECT)
 766         return 1;
 767
 768     // we support OPTIONS and TRACE directed at us (with a 501 reply, for now)
 769     // we also support forwarding OPTIONS and TRACE, except for the *-URI ones
 770     if (r->method == Http::METHOD_OPTIONS || r->method == Http::METHOD_TRACE)
 771         return (r->header.getInt64(HDR_MAX_FORWARDS) == 0 || r->url.path() != URL::Asterisk());
 772
 773     if (r->method == Http::METHOD_PURGE)
 774         return 1;
 775
 776     /* does method match the protocol? */
 777     switch (r->url.getScheme()) {
 778
 779     case AnyP::PROTO_URN:
 780
 781     case AnyP::PROTO_HTTP:
 782
 783     case AnyP::PROTO_CACHE_OBJECT:
 784         rc = 1;
 785         break;
 786
 787     case AnyP::PROTO_FTP:
 788
 789         if (r->method == Http::METHOD_PUT)
 790             rc = 1;
 791
 792     case AnyP::PROTO_GOPHER:
 793
 794     case AnyP::PROTO_WAIS:
 795
 796     case AnyP::PROTO_WHOIS:
 797         if (r->method == Http::METHOD_GET)
 798             rc = 1;
 799         else if (r->method == Http::METHOD_HEAD)
 800             rc = 1;
 801
 802         break;
 803
 804     case AnyP::PROTO_HTTPS:
 805 #if USE_OPENSSL
 806
 807         rc = 1;
 808
 809         break;
 810
 811 #else
 812         /*
 813         * Squid can't originate an SSL connection, so it should
 814         * never receive an "https:" URL.  It should always be
 815         * CONNECT instead.
 816         */
 817         rc = 0;
 818
 819 #endif
 820
 821     default:
 822         break;
 823     }
 824
 825     return rc;
 826 }
 827
 828 /*
 829  * Quick-n-dirty host extraction from a URL.  Steps:
 830  *      Look for a colon
 831  *      Skip any '/' after the colon
 832  *      Copy the next SQUID_MAXHOSTNAMELEN bytes to host[]
 833  *      Look for an ending '/' or ':' and terminate
 834  *      Look for login info preceeded by '@'
 835  */
 836
 837 class URLHostName
 838 {
 839
 840 public:
 841     char * extract(char const *url);
 842
 843 private:
 844     static char Host [SQUIDHOSTNAMELEN];
 845     void init(char const *);
 846     void findHostStart();
 847     void trimTrailingChars();
 848     void trimAuth();
 849     char const *hostStart;
 850     char const *url;
 851 };
 852
 853 char *
 854 urlHostname(const char *url)
 855 {
 856     return URLHostName().extract(url);
 857 }
 858
 859 char URLHostName::Host[SQUIDHOSTNAMELEN];
 860
 861 void
 862 URLHostName::init(char const *aUrl)
 863 {
 864     Host[0] = '\0';
 865     url = aUrl;
 866 }
 867
 868 void
 869 URLHostName::findHostStart()
 870 {
 871     if (NULL == (hostStart = strchr(url, ':')))
 872         return;
 873
 874     ++hostStart;
 875
 876     while (*hostStart != '\0' && *hostStart == '/')
 877         ++hostStart;
 878
 879     if (*hostStart == ']')
 880         ++hostStart;
 881 }
 882
 883 void
 884 URLHostName::trimTrailingChars()
 885 {
 886     char *t;
 887
 888     if ((t = strchr(Host, '/')))
 889         *t = '\0';
 890
 891     if ((t = strrchr(Host, ':')))
 892         *t = '\0';
 893
 894     if ((t = strchr(Host, ']')))
 895         *t = '\0';
 896 }
 897
 898 void
 899 URLHostName::trimAuth()
 900 {
 901     char *t;
 902
 903     if ((t = strrchr(Host, '@'))) {
 904         ++t;
 905         memmove(Host, t, strlen(t) + 1);
 906     }
 907 }
 908
 909 char *
 910 URLHostName::extract(char const *aUrl)
 911 {
 912     init(aUrl);
 913     findHostStart();
 914
 915     if (hostStart == NULL)
 916         return NULL;
 917
 918     xstrncpy(Host, hostStart, SQUIDHOSTNAMELEN);
 919
 920     trimTrailingChars();
 921
 922     trimAuth();
 923
 924     return Host;
 925 }
 926