src/adaptation/ecap/Host.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 93    eCAP Interface */
  10
  11 #include "squid.h"
  12 #include <libecap/adapter/service.h>
  13 #include <libecap/common/names.h>
  14 #include <libecap/common/registry.h>
  15 #include "adaptation/ecap/Host.h"
  16 #include "adaptation/ecap/MessageRep.h"
  17 #include "adaptation/ecap/ServiceRep.h"
  18 #include "base/TextException.h"
  19 #include "HttpReply.h"
  20 #include "HttpRequest.h"
  21
  22 const libecap::Name Adaptation::Ecap::protocolInternal("internal", libecap::Name::NextId());
  23 const libecap::Name Adaptation::Ecap::protocolCacheObj("cache_object", libecap::Name::NextId());
  24 const libecap::Name Adaptation::Ecap::protocolIcp("ICP", libecap::Name::NextId());
  25 #if USE_HTCP
  26 const libecap::Name Adaptation::Ecap::protocolHtcp("Htcp", libecap::Name::NextId());
  27 #endif
  28 const libecap::Name Adaptation::Ecap::protocolIcy("ICY", libecap::Name::NextId());
  29 const libecap::Name Adaptation::Ecap::protocolUnknown("_unknown_", libecap::Name::NextId());
  30
  31 const libecap::Name Adaptation::Ecap::metaBypassable("bypassable", libecap::Name::NextId());
  32
  33 /// the host application (i.e., Squid) wrapper registered with libecap
  34 static libecap::shared_ptr<Adaptation::Ecap::Host> TheHost;
  35
  36 Adaptation::Ecap::Host::Host()
  37 {
  38     // assign our host-specific IDs to well-known names
  39     // this code can run only once
  40
  41     libecap::headerTransferEncoding.assignHostId(HDR_TRANSFER_ENCODING);
  42     libecap::headerReferer.assignHostId(HDR_REFERER);
  43     libecap::headerContentLength.assignHostId(HDR_CONTENT_LENGTH);
  44     libecap::headerVia.assignHostId(HDR_VIA);
  45     // TODO: libecap::headerXClientIp.assignHostId(HDR_X_CLIENT_IP);
  46     // TODO: libecap::headerXServerIp.assignHostId(HDR_X_SERVER_IP);
  47
  48     libecap::protocolHttp.assignHostId(AnyP::PROTO_HTTP);
  49     libecap::protocolHttps.assignHostId(AnyP::PROTO_HTTPS);
  50     libecap::protocolFtp.assignHostId(AnyP::PROTO_FTP);
  51     libecap::protocolGopher.assignHostId(AnyP::PROTO_GOPHER);
  52     libecap::protocolWais.assignHostId(AnyP::PROTO_WAIS);
  53     libecap::protocolUrn.assignHostId(AnyP::PROTO_URN);
  54     libecap::protocolWhois.assignHostId(AnyP::PROTO_WHOIS);
  55     protocolCacheObj.assignHostId(AnyP::PROTO_CACHE_OBJECT);
  56     protocolIcp.assignHostId(AnyP::PROTO_ICP);
  57 #if USE_HTCP
  58     protocolHtcp.assignHostId(AnyP::PROTO_HTCP);
  59 #endif
  60     protocolIcy.assignHostId(AnyP::PROTO_ICY);
  61     protocolUnknown.assignHostId(AnyP::PROTO_UNKNOWN);
  62
  63     // allows adapter to safely ignore this in adapter::Service::configure()
  64     metaBypassable.assignHostId(1);
  65 }
  66
  67 std::string
  68 Adaptation::Ecap::Host::uri() const
  69 {
  70     return "ecap://squid-cache.org/ecap/hosts/squid";
  71 }
  72
  73 void
  74 Adaptation::Ecap::Host::describe(std::ostream &os) const
  75 {
  76     os << PACKAGE_NAME << " v" << PACKAGE_VERSION;
  77 }
  78
  79 /// Strips libecap version components not affecting compatibility decisions.
  80 static SBuf
  81 EssentialVersion(const SBuf &raw)
  82 {
  83     // all libecap x.y.* releases are supposed to be compatible so we strip
  84     // everything after the second period
  85     const SBuf::size_type minorPos = raw.find('.');
  86     const SBuf::size_type microPos = minorPos == SBuf::npos ?
  87                                      SBuf::npos : raw.find('.', minorPos+1);
  88     return raw.substr(0, microPos); // becomes raw if microPos is npos
  89 }
  90
  91 /// If "their" libecap version is not compatible with what Squid has been built
  92 /// with, then complain and return false.
  93 static bool
  94 SupportedVersion(const char *vTheir, const char *them)
  95 {
  96     if (!vTheir || !*vTheir) {
  97         debugs(93, DBG_CRITICAL, "ERROR: Cannot use " << them <<
  98                " with libecap prior to v1.0.");
  99         return false;
 100     }
 101
 102     // we support what we are built with
 103     const SBuf vSupported(LIBECAP_VERSION);
 104     debugs(93, 2, them << " with libecap v" << vTheir << "; us: v" << vSupported);
 105
 106     if (EssentialVersion(SBuf(vTheir)) == EssentialVersion(vSupported))
 107         return true; // their version is supported
 108
 109     debugs(93, DBG_CRITICAL, "ERROR: Cannot use " << them <<
 110            " with libecap v" << vTheir <<
 111            ": incompatible with supported libecap v" << vSupported);
 112     return false;
 113 }
 114
 115 void
 116 Adaptation::Ecap::Host::noteVersionedService(const char *vGiven, const libecap::weak_ptr<libecap::adapter::Service> &weak)
 117 {
 118     /*
 119      * Check that libecap used to build the service is compatible with ours.
 120      * This has to be done using vGiven string and not Service object itself
 121      * because dereferencing a Service pointer coming from an unsupported
 122      * version is unsafe.
 123      */
 124     if (SupportedVersion(vGiven, "eCAP service built")) {
 125         Must(!weak.expired());
 126         RegisterAdapterService(weak.lock());
 127     }
 128 }
 129
 130 static int
 131 SquidLogLevel(libecap::LogVerbosity lv)
 132 {
 133     if (lv.critical())
 134         return DBG_CRITICAL; // is it a good idea to ignore other flags?
 135
 136     if (lv.large())
 137         return DBG_DATA; // is it a good idea to ignore other flags?
 138
 139     if (lv.application())
 140         return DBG_IMPORTANT; // is it a good idea to ignore other flags?
 141
 142     return 2 + 2*lv.debugging() + 3*lv.operation() + 2*lv.xaction();
 143 }
 144
 145 std::ostream *
 146 Adaptation::Ecap::Host::openDebug(libecap::LogVerbosity lv)
 147 {
 148     const int squidLevel = SquidLogLevel(lv);
 149     const int squidSection = 93; // XXX: this should be a global constant
 150     // XXX: Debug.h should provide this to us
 151     if ((Debug::level = squidLevel) <= Debug::Levels[squidSection])
 152         return &Debug::getDebugOut();
 153     else
 154         return NULL;
 155 }
 156
 157 void
 158 Adaptation::Ecap::Host::closeDebug(std::ostream *debug)
 159 {
 160     if (debug)
 161         Debug::finishDebug();
 162 }
 163
 164 Adaptation::Ecap::Host::MessagePtr
 165 Adaptation::Ecap::Host::newRequest() const
 166 {
 167     return MessagePtr(new Adaptation::Ecap::MessageRep(new HttpRequest));
 168 }
 169
 170 Adaptation::Ecap::Host::MessagePtr
 171 Adaptation::Ecap::Host::newResponse() const
 172 {
 173     return MessagePtr(new Adaptation::Ecap::MessageRep(new HttpReply));
 174 }
 175
 176 void
 177 Adaptation::Ecap::Host::Register()
 178 {
 179     if (!TheHost && SupportedVersion(libecap::VersionString(),
 180                                      "Squid executable dynamically linked")) {
 181         TheHost.reset(new Adaptation::Ecap::Host);
 182         libecap::RegisterHost(TheHost);
 183     }
 184 }
 185