src/client_side_reply.h

   1 /*
   2  * Copyright (C) 1996-2022 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 #ifndef SQUID_CLIENTSIDEREPLY_H
  10 #define SQUID_CLIENTSIDEREPLY_H
  11
  12 #include "acl/forward.h"
  13 #include "client_side_request.h"
  14 #include "ip/forward.h"
  15 #include "RequestFlags.h"
  16 #include "StoreClient.h"
  17
  18 class ErrorState;
  19
  20 /* XXX make static method */
  21
  22 class clientReplyContext : public RefCountable, public StoreClient
  23 {
  24     CBDATA_CLASS(clientReplyContext);
  25
  26 public:
  27     static STCB CacheHit;
  28     static STCB HandleIMSReply;
  29     static STCB SendMoreData;
  30
  31     clientReplyContext(ClientHttpRequest *);
  32     ~clientReplyContext();
  33
  34     void saveState();
  35     void restoreState();
  36     void purgeRequest ();
  37     void sendClientUpstreamResponse();
  38     void doGetMoreData();
  39     void identifyStoreObject();
  40     void identifyFoundObject(StoreEntry *entry, const char *detail);
  41     int storeOKTransferDone() const;
  42     int storeNotOKTransferDone() const;
  43     /// replaces current response store entry with the given one
  44     void setReplyToStoreEntry(StoreEntry *e, const char *reason);
  45     /// builds error using clientBuildError() and calls setReplyToError() below
  46     void setReplyToError(err_type, Http::StatusCode, const HttpRequestMethod&, char const *, const ConnStateData *, HttpRequest *, const char *,
  47 #if USE_AUTH
  48                          Auth::UserRequest::Pointer);
  49 #else
  50                          void * unused);
  51 #endif
  52     /// creates a store entry for the reply and appends err to it
  53     void setReplyToError(const HttpRequestMethod& method, ErrorState *err);
  54     /// creates a store entry for the reply and appends error reply to it
  55     void setReplyToReply(HttpReply *reply);
  56     void createStoreEntry(const HttpRequestMethod& m, RequestFlags flags);
  57     void removeStoreReference(store_client ** scp, StoreEntry ** ep);
  58     void removeClientStoreReference(store_client **scp, ClientHttpRequest *http);
  59     void startError(ErrorState * err);
  60     void processExpired();
  61     clientStream_status_t replyStatus();
  62     void processMiss();
  63     void traceReply(clientStreamNode * node);
  64     const char *storeId() const { return (http->store_id.size() > 0 ? http->store_id.termedBuf() : http->uri); }
  65
  66     Http::StatusCode purgeStatus;
  67
  68     /* StoreClient API */
  69     virtual LogTags *loggingTags() const;
  70
  71     ClientHttpRequest *http;
  72     /// Base reply header bytes received from Store.
  73     /// Compatible with ClientHttpRequest::Out::offset.
  74     /// Not to be confused with ClientHttpRequest::Out::headers_sz.
  75     int headers_sz;
  76     store_client *sc;       /* The store_client we're using */
  77     StoreIOBuffer tempBuffer;   /* For use in validating requests via IMS */
  78     int old_reqsize;        /* ... again, for the buffer */
  79     size_t reqsize;
  80     size_t reqofs;
  81     char tempbuf[HTTP_REQBUF_SZ];   ///< a temporary buffer if we need working storage
  82
  83     struct Flags {
  84         Flags() : storelogiccomplete(0), complete(0), headersSent(false) {}
  85
  86         unsigned storelogiccomplete:1;
  87         unsigned complete:1;        ///< we have read all we can from upstream
  88         bool headersSent;
  89     } flags;
  90     clientStreamNode *ourNode;  /* This will go away if/when this file gets refactored some more */
  91
  92 private:
  93     /* StoreClient API */
  94     virtual void fillChecklist(ACLFilledChecklist &) const;
  95
  96     clientStreamNode *getNextNode() const;
  97     void makeThisHead();
  98     bool errorInStream(StoreIOBuffer const &result, size_t const &sizeToProcess)const ;
  99     void sendStreamError(StoreIOBuffer const &result);
 100     void pushStreamData(StoreIOBuffer const &result, char *source);
 101     clientStreamNode * next() const;
 102     StoreIOBuffer holdingBuffer;
 103     HttpReply *reply;
 104     void processReplyAccess();
 105     static ACLCB ProcessReplyAccessResult;
 106     void processReplyAccessResult(const Acl::Answer &accessAllowed);
 107     void cloneReply();
 108     void buildReplyHeader ();
 109     bool alwaysAllowResponse(Http::StatusCode sline) const;
 110     int checkTransferDone();
 111     void processOnlyIfCachedMiss();
 112     bool processConditional();
 113     void cacheHit(StoreIOBuffer result);
 114     void handleIMSReply(StoreIOBuffer result);
 115     void sendMoreData(StoreIOBuffer result);
 116     void triggerInitialStoreRead();
 117     void sendClientOldEntry();
 118     void purgeAllCached();
 119     /// attempts to release the cached entry
 120     /// \returns whether the entry was released
 121     bool purgeEntry(StoreEntry &, const Http::MethodType, const char *descriptionPrefix = "");
 122     /// releases both cached GET and HEAD entries
 123     void purgeDoPurge();
 124     void forgetHit();
 125     bool blockedHit() const;
 126     const char *storeLookupString(bool found) const { return found ? "match" : "mismatch"; }
 127     void detailStoreLookup(const char *detail);
 128
 129     void sendBodyTooLargeError();
 130     void sendPreconditionFailedError();
 131     void sendNotModified();
 132     void sendNotModifiedOrPreconditionFailedError();
 133
 134     /// Classification of the initial Store lookup.
 135     /// This very first lookup happens without the Vary-driven key augmentation.
 136     /// TODO: Exclude internal Store match bans from the "mismatch" category.
 137     const char *firstStoreLookup_ = nullptr;
 138
 139     StoreEntry *old_entry;
 140     /* ... for entry to be validated */
 141     store_client *old_sc;
 142     time_t old_lastmod;
 143     String old_etag;
 144
 145     bool deleting;
 146
 147     typedef enum {
 148         crNone = 0, ///< collapsed revalidation is not allowed for this context
 149         crInitiator, ///< we initiated collapsed revalidation request
 150         crSlave ///< we collapsed on the existing revalidation request
 151     } CollapsedRevalidation;
 152
 153     CollapsedRevalidation collapsedRevalidation;
 154 };
 155
 156 // TODO: move to SideAgent parent, when we have one
 157 void purgeEntriesByUrl(HttpRequest *, const char *);
 158
 159 #endif /* SQUID_CLIENTSIDEREPLY_H */
 160