methods/https.cc

   1 //-*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: http.cc,v 1.59 2004/05/08 19:42:35 mdz Exp $
   4 /* ######################################################################
   5
   6    HTTPS Acquire Method - This is the HTTPS acquire method for APT.
   7
   8    It uses libcurl
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #include <config.h>
  14
  15 #include <apt-pkg/fileutl.h>
  16 #include <apt-pkg/acquire-method.h>
  17 #include <apt-pkg/error.h>
  18 #include <apt-pkg/hashes.h>
  19 #include <apt-pkg/netrc.h>
  20 #include <apt-pkg/configuration.h>
  21 #include <apt-pkg/macros.h>
  22 #include <apt-pkg/strutl.h>
  23 #include <apt-pkg/proxy.h>
  24
  25 #include <sys/stat.h>
  26 #include <sys/time.h>
  27 #include <unistd.h>
  28 #include <stdio.h>
  29 #include <iostream>
  30 #include <sstream>
  31 #include <ctype.h>
  32 #include <stdlib.h>
  33
  34 #include "https.h"
  35
  36 #include <apti18n.h>
  37                                                                         /*}}}*/
  38 using namespace std;
  39
  40 size_t
  41 HttpsMethod::parse_header(void *buffer, size_t size, size_t nmemb, void *userp)
  42 {
  43    size_t len = size * nmemb;
  44    HttpsMethod *me = (HttpsMethod *)userp;
  45    std::string line((char*) buffer, len);
  46    for (--len; len > 0; --len)
  47       if (isspace(line[len]) == 0)
  48       {
  49          ++len;
  50          break;
  51       }
  52    line.erase(len);
  53
  54    if (line.empty() == true)
  55    {
  56       if (me->Server->Result != 416 && me->Server->StartPos != 0)
  57          ;
  58       else if (me->Server->Result == 416 && me->Server->Size == me->File->FileSize())
  59       {
  60          me->Server->Result = 200;
  61          me->Server->StartPos = me->Server->Size;
  62       }
  63       else
  64          me->Server->StartPos = 0;
  65
  66       me->File->Truncate(me->Server->StartPos);
  67       me->File->Seek(me->Server->StartPos);
  68    }
  69    else if (me->Server->HeaderLine(line) == false)
  70       return 0;
  71
  72    return size*nmemb;
  73 }
  74
  75 size_t
  76 HttpsMethod::write_data(void *buffer, size_t size, size_t nmemb, void *userp)
  77 {
  78    HttpsMethod *me = (HttpsMethod *)userp;
  79
  80    if (me->Res.Size == 0)
  81       me->URIStart(me->Res);
  82    if(me->File->Write(buffer, size*nmemb) != true)
  83       return false;
  84
  85    if(me->Queue->MaximumSize > 0 && me->File->Tell() > me->Queue->MaximumSize)
  86       return _error->Error("Writing more data than expected (%llu > %llu)",
  87                            me->TotalWritten, me->Queue->MaximumSize);
  88
  89    return size*nmemb;
  90 }
  91
  92 int
  93 HttpsMethod::progress_callback(void *clientp, double dltotal, double /*dlnow*/,
  94                               double /*ultotal*/, double /*ulnow*/)
  95 {
  96    HttpsMethod *me = (HttpsMethod *)clientp;
  97    if(dltotal > 0 && me->Res.Size == 0) {
  98       me->Res.Size = (unsigned long long)dltotal;
  99    }
 100    return 0;
 101 }
 102
 103 // HttpsServerState::HttpsServerState - Constructor                     /*{{{*/
 104 HttpsServerState::HttpsServerState(URI Srv,HttpsMethod * /*Owner*/) : ServerState(Srv, NULL)
 105 {
 106    TimeOut = _config->FindI("Acquire::https::Timeout",TimeOut);
 107    Reset();
 108 }
 109                                                                         /*}}}*/
 110
 111 void HttpsMethod::SetupProxy()                                          /*{{{*/
 112 {
 113    URI ServerName = Queue->Uri;
 114
 115    // Determine the proxy setting
 116    AutoDetectProxy(ServerName);
 117
 118    // Curl should never read proxy settings from the environment, as
 119    // we determine which proxy to use.  Do this for consistency among
 120    // methods and prevent an environment variable overriding a
 121    // no-proxy ("DIRECT") setting in apt.conf.
 122    curl_easy_setopt(curl, CURLOPT_PROXY, "");
 123
 124    // Determine the proxy setting - try https first, fallback to http and use env at last
 125    string UseProxy = _config->Find("Acquire::https::Proxy::" + ServerName.Host,
 126                                    _config->Find("Acquire::http::Proxy::" + ServerName.Host).c_str());
 127
 128    if (UseProxy.empty() == true)
 129       UseProxy = _config->Find("Acquire::https::Proxy", _config->Find("Acquire::http::Proxy").c_str());
 130
 131    // User want to use NO proxy, so nothing to setup
 132    if (UseProxy == "DIRECT")
 133       return;
 134
 135    if (UseProxy.empty() == false)
 136    {
 137       // Parse no_proxy, a comma (,) separated list of domains we don't want to use
 138       // a proxy for so we stop right here if it is in the list
 139       if (getenv("no_proxy") != 0 && CheckDomainList(ServerName.Host,getenv("no_proxy")) == true)
 140          return;
 141    } else {
 142       const char* result = getenv("https_proxy");
 143       // FIXME: Fall back to http_proxy is to remain compatible with
 144       // existing setups and behaviour of apt.conf.  This should be
 145       // deprecated in the future (including apt.conf).  Most other
 146       // programs do not fall back to http proxy settings and neither
 147       // should Apt.
 148       if (result == NULL)
 149          result = getenv("http_proxy");
 150       UseProxy = result == NULL ? "" : result;
 151    }
 152
 153    // Determine what host and port to use based on the proxy settings
 154    if (UseProxy.empty() == false)
 155    {
 156       Proxy = UseProxy;
 157       if (Proxy.Port != 1)
 158          curl_easy_setopt(curl, CURLOPT_PROXYPORT, Proxy.Port);
 159       curl_easy_setopt(curl, CURLOPT_PROXY, Proxy.Host.c_str());
 160       if (Proxy.User.empty() == false || Proxy.Password.empty() == false)
 161       {
 162          curl_easy_setopt(curl, CURLOPT_PROXYUSERNAME, Proxy.User.c_str());
 163          curl_easy_setopt(curl, CURLOPT_PROXYPASSWORD, Proxy.Password.c_str());
 164       }
 165    }
 166 }                                                                       /*}}}*/
 167 // HttpsMethod::Fetch - Fetch an item                                   /*{{{*/
 168 // ---------------------------------------------------------------------
 169 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 170    depth. */
 171 bool HttpsMethod::Fetch(FetchItem *Itm)
 172 {
 173    struct stat SBuf;
 174    struct curl_slist *headers=NULL;
 175    char curl_errorstr[CURL_ERROR_SIZE];
 176    URI Uri = Itm->Uri;
 177    string remotehost = Uri.Host;
 178
 179    // TODO:
 180    //       - http::Pipeline-Depth
 181    //       - error checking/reporting
 182    //       - more debug options? (CURLOPT_DEBUGFUNCTION?)
 183
 184    curl_easy_reset(curl);
 185    SetupProxy();
 186
 187    maybe_add_auth (Uri, _config->FindFile("Dir::Etc::netrc"));
 188
 189    // callbacks
 190    curl_easy_setopt(curl, CURLOPT_URL, static_cast<string>(Uri).c_str());
 191    curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, parse_header);
 192    curl_easy_setopt(curl, CURLOPT_WRITEHEADER, this);
 193    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
 194    curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);
 195    curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progress_callback);
 196    curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, this);
 197    // options
 198    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, false);
 199    curl_easy_setopt(curl, CURLOPT_FILETIME, true);
 200    // only allow curl to handle https, not the other stuff it supports
 201    curl_easy_setopt(curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTPS);
 202    curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTPS);
 203
 204    // SSL parameters are set by default to the common (non mirror-specific) value
 205    // if available (or a default one) and gets overload by mirror-specific ones.
 206
 207    // File containing the list of trusted CA.
 208    string cainfo = _config->Find("Acquire::https::CaInfo","");
 209    string knob = "Acquire::https::"+remotehost+"::CaInfo";
 210    cainfo = _config->Find(knob.c_str(),cainfo.c_str());
 211    if(cainfo.empty() == false)
 212       curl_easy_setopt(curl, CURLOPT_CAINFO,cainfo.c_str());
 213
 214    // Check server certificate against previous CA list ...
 215    bool peer_verify = _config->FindB("Acquire::https::Verify-Peer",true);
 216    knob = "Acquire::https::" + remotehost + "::Verify-Peer";
 217    peer_verify = _config->FindB(knob.c_str(), peer_verify);
 218    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, peer_verify);
 219
 220    // ... and hostname against cert CN or subjectAltName
 221    bool verify = _config->FindB("Acquire::https::Verify-Host",true);
 222    knob = "Acquire::https::"+remotehost+"::Verify-Host";
 223    verify = _config->FindB(knob.c_str(),verify);
 224    int const default_verify = (verify == true) ? 2 : 0;
 225    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, default_verify);
 226
 227    // Also enforce issuer of server certificate using its cert
 228    string issuercert = _config->Find("Acquire::https::IssuerCert","");
 229    knob = "Acquire::https::"+remotehost+"::IssuerCert";
 230    issuercert = _config->Find(knob.c_str(),issuercert.c_str());
 231    if(issuercert.empty() == false)
 232       curl_easy_setopt(curl, CURLOPT_ISSUERCERT,issuercert.c_str());
 233
 234    // For client authentication, certificate file ...
 235    string pem = _config->Find("Acquire::https::SslCert","");
 236    knob = "Acquire::https::"+remotehost+"::SslCert";
 237    pem = _config->Find(knob.c_str(),pem.c_str());
 238    if(pem.empty() == false)
 239       curl_easy_setopt(curl, CURLOPT_SSLCERT, pem.c_str());
 240
 241    // ... and associated key.
 242    string key = _config->Find("Acquire::https::SslKey","");
 243    knob = "Acquire::https::"+remotehost+"::SslKey";
 244    key = _config->Find(knob.c_str(),key.c_str());
 245    if(key.empty() == false)
 246       curl_easy_setopt(curl, CURLOPT_SSLKEY, key.c_str());
 247
 248    // Allow forcing SSL version to SSLv3 or TLSv1 (SSLv2 is not
 249    // supported by GnuTLS).
 250    long final_version = CURL_SSLVERSION_DEFAULT;
 251    string sslversion = _config->Find("Acquire::https::SslForceVersion","");
 252    knob = "Acquire::https::"+remotehost+"::SslForceVersion";
 253    sslversion = _config->Find(knob.c_str(),sslversion.c_str());
 254    if(sslversion == "TLSv1")
 255      final_version = CURL_SSLVERSION_TLSv1;
 256    else if(sslversion == "SSLv3")
 257      final_version = CURL_SSLVERSION_SSLv3;
 258    curl_easy_setopt(curl, CURLOPT_SSLVERSION, final_version);
 259
 260    // CRL file
 261    string crlfile = _config->Find("Acquire::https::CrlFile","");
 262    knob = "Acquire::https::"+remotehost+"::CrlFile";
 263    crlfile = _config->Find(knob.c_str(),crlfile.c_str());
 264    if(crlfile.empty() == false)
 265       curl_easy_setopt(curl, CURLOPT_CRLFILE, crlfile.c_str());
 266
 267    // cache-control
 268    if(_config->FindB("Acquire::https::No-Cache",
 269         _config->FindB("Acquire::http::No-Cache",false)) == false)
 270    {
 271       // cache enabled
 272       if (_config->FindB("Acquire::https::No-Store",
 273                 _config->FindB("Acquire::http::No-Store",false)) == true)
 274          headers = curl_slist_append(headers,"Cache-Control: no-store");
 275       stringstream ss;
 276       ioprintf(ss, "Cache-Control: max-age=%u", _config->FindI("Acquire::https::Max-Age",
 277                 _config->FindI("Acquire::http::Max-Age",0)));
 278       headers = curl_slist_append(headers, ss.str().c_str());
 279    } else {
 280       // cache disabled by user
 281       headers = curl_slist_append(headers, "Cache-Control: no-cache");
 282       headers = curl_slist_append(headers, "Pragma: no-cache");
 283    }
 284    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
 285
 286    // speed limit
 287    int const dlLimit = _config->FindI("Acquire::https::Dl-Limit",
 288                 _config->FindI("Acquire::http::Dl-Limit",0))*1024;
 289    if (dlLimit > 0)
 290       curl_easy_setopt(curl, CURLOPT_MAX_RECV_SPEED_LARGE, dlLimit);
 291
 292    // set header
 293    curl_easy_setopt(curl, CURLOPT_USERAGENT,
 294         _config->Find("Acquire::https::User-Agent",
 295                 _config->Find("Acquire::http::User-Agent",
 296                         "Debian APT-CURL/1.0 (" PACKAGE_VERSION ")").c_str()).c_str());
 297
 298    // set timeout
 299    int const timeout = _config->FindI("Acquire::https::Timeout",
 300                 _config->FindI("Acquire::http::Timeout",120));
 301    curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, timeout);
 302    //set really low lowspeed timeout (see #497983)
 303    curl_easy_setopt(curl, CURLOPT_LOW_SPEED_LIMIT, DL_MIN_SPEED);
 304    curl_easy_setopt(curl, CURLOPT_LOW_SPEED_TIME, timeout);
 305
 306    // set redirect options and default to 10 redirects
 307    bool const AllowRedirect = _config->FindB("Acquire::https::AllowRedirect",
 308         _config->FindB("Acquire::http::AllowRedirect",true));
 309    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, AllowRedirect);
 310    curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 10);
 311
 312    // debug
 313    if(_config->FindB("Debug::Acquire::https", false))
 314       curl_easy_setopt(curl, CURLOPT_VERBOSE, true);
 315
 316    // error handling
 317    curl_errorstr[0] = '\0';
 318    curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 319
 320    // If we ask for uncompressed files servers might respond with content-
 321    // negotiation which lets us end up with compressed files we do not support,
 322    // see 657029, 657560 and co, so if we have no extension on the request
 323    // ask for text only. As a sidenote: If there is nothing to negotate servers
 324    // seem to be nice and ignore it.
 325    if (_config->FindB("Acquire::https::SendAccept", _config->FindB("Acquire::http::SendAccept", true)) == true)
 326    {
 327       size_t const filepos = Itm->Uri.find_last_of('/');
 328       string const file = Itm->Uri.substr(filepos + 1);
 329       if (flExtension(file) == file)
 330          headers = curl_slist_append(headers, "Accept: text/*");
 331    }
 332
 333    // if we have the file send an if-range query with a range header
 334    if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
 335    {
 336       std::string Buf;
 337       strprintf(Buf, "Range: bytes=%lli-", (long long) SBuf.st_size);
 338       headers = curl_slist_append(headers, Buf.c_str());
 339       strprintf(Buf, "If-Range: %s", TimeRFC1123(SBuf.st_mtime).c_str());
 340       headers = curl_slist_append(headers, Buf.c_str());
 341    }
 342    else if(Itm->LastModified > 0)
 343    {
 344       curl_easy_setopt(curl, CURLOPT_TIMECONDITION, CURL_TIMECOND_IFMODSINCE);
 345       curl_easy_setopt(curl, CURLOPT_TIMEVALUE, Itm->LastModified);
 346    }
 347
 348    // go for it - if the file exists, append on it
 349    File = new FileFd(Itm->DestFile, FileFd::WriteAny);
 350    Server = new HttpsServerState(Itm->Uri, this);
 351
 352    // keep apt updated
 353    Res.Filename = Itm->DestFile;
 354
 355    // get it!
 356    CURLcode success = curl_easy_perform(curl);
 357
 358    // If the server returns 200 OK but the If-Modified-Since condition is not
 359    // met, CURLINFO_CONDITION_UNMET will be set to 1
 360    long curl_condition_unmet = 0;
 361    curl_easy_getinfo(curl, CURLINFO_CONDITION_UNMET, &curl_condition_unmet);
 362
 363    File->Close();
 364    curl_slist_free_all(headers);
 365
 366    // cleanup
 367    if (success != 0)
 368    {
 369       _error->Error("%s", curl_errorstr);
 370       unlink(File->Name().c_str());
 371       return false;
 372    }
 373
 374    // server says file not modified
 375    if (Server->Result == 304 || curl_condition_unmet == 1)
 376    {
 377       unlink(File->Name().c_str());
 378       Res.IMSHit = true;
 379       Res.LastModified = Itm->LastModified;
 380       Res.Size = 0;
 381       URIDone(Res);
 382       return true;
 383    }
 384    Res.IMSHit = false;
 385
 386    if (Server->Result != 200 && // OK
 387          Server->Result != 206 && // Partial
 388          Server->Result != 416) // invalid Range
 389    {
 390       char err[255];
 391       snprintf(err, sizeof(err) - 1, "HttpError%i", Server->Result);
 392       SetFailReason(err);
 393       _error->Error("%s", err);
 394       // unlink, no need keep 401/404 page content in partial/
 395       unlink(File->Name().c_str());
 396       return false;
 397    }
 398
 399    struct stat resultStat;
 400    if (unlikely(stat(File->Name().c_str(), &resultStat) != 0))
 401    {
 402       _error->Errno("stat", "Unable to access file %s", File->Name().c_str());
 403       return false;
 404    }
 405    Res.Size = resultStat.st_size;
 406
 407    // invalid range-request
 408    if (Server->Result == 416)
 409    {
 410       unlink(File->Name().c_str());
 411       Res.Size = 0;
 412       delete File;
 413       Redirect(Itm->Uri);
 414       return true;
 415    }
 416
 417    // Timestamp
 418    curl_easy_getinfo(curl, CURLINFO_FILETIME, &Res.LastModified);
 419    if (Res.LastModified != -1)
 420    {
 421       struct timeval times[2];
 422       times[0].tv_sec = Res.LastModified;
 423       times[1].tv_sec = Res.LastModified;
 424       times[0].tv_usec = times[1].tv_usec = 0;
 425       utimes(File->Name().c_str(), times);
 426    }
 427    else
 428       Res.LastModified = resultStat.st_mtime;
 429
 430    // take hashes
 431    Hashes Hash;
 432    FileFd Fd(Res.Filename, FileFd::ReadOnly);
 433    Hash.AddFD(Fd);
 434    Res.TakeHashes(Hash);
 435
 436    // keep apt updated
 437    URIDone(Res);
 438
 439    // cleanup
 440    Res.Size = 0;
 441    delete File;
 442
 443    return true;
 444 }
 445
 446 int main()
 447 {
 448    setlocale(LC_ALL, "");
 449
 450    HttpsMethod Mth;
 451    curl_global_init(CURL_GLOBAL_SSL) ;
 452
 453    Mth.DropPrivsOrDie();
 454
 455    return Mth.Run();
 456 }
 457