don't sent Range requests if we know its not accepted

If the server told us in a previous request that it isn't supporting
Ranges with bytes via an Accept-Ranges header missing bytes, we don't
try to formulate requests using Ranges.

methods/http.cc

@@ -906,7 +906,7 @@ void HttpMethod::SendReq(FetchItem *Itm)
 
    // Check for a partial file and send if-queries accordingly
    struct stat SBuf;
-   if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
+   if (Server->RangesAllowed && stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
       Req << "Range: bytes=" << std::to_string(SBuf.st_size) << "-\r\n"
 	 << "If-Range: " << TimeRFC1123(SBuf.st_mtime, false) << "\r\n";
    else if (Itm->LastModified != 0)

methods/https.cc

@@ -382,8 +382,15 @@ bool HttpsMethod::Fetch(FetchItem *Itm)
 	 headers = curl_slist_append(headers, "Accept: text/*");
    }
 
+   // go for it - if the file exists, append on it
+   File = new FileFd(Itm->DestFile, FileFd::WriteAny);
+   if (Server == nullptr || Server->Comp(Itm->Uri) == false)
+      Server = CreateServerState(Itm->Uri);
+   else
+      Server->Reset(false);
+
    // if we have the file send an if-range query with a range header
-   if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
+   if (Server->RangesAllowed && stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
    {
       std::string Buf;
       strprintf(Buf, "Range: bytes=%lli-", (long long) SBuf.st_size);
@@ -397,12 +404,6 @@ bool HttpsMethod::Fetch(FetchItem *Itm)
       curl_easy_setopt(curl, CURLOPT_TIMEVALUE, Itm->LastModified);
    }
 
-   // go for it - if the file exists, append on it
-   File = new FileFd(Itm->DestFile, FileFd::WriteAny);
-   if (Server == nullptr || Server->Comp(Itm->Uri) == false)
-      Server = CreateServerState(Itm->Uri);
-   else
-      Server->Reset(false);
    if (Server->InitHashes(Itm->ExpectedHashes) == false)
       return false;
 

methods/server.cc

@@ -227,6 +227,15 @@ bool ServerState::HeaderLine(string Line)
       return true;
    }
 
+   if (stringcasecmp(Tag, "Accept-Ranges:") == 0)
+   {
+      std::string ranges = ',' + Val + ',';
+      ranges.erase(std::remove(ranges.begin(), ranges.end(), ' '), ranges.end());
+      if (ranges.find(",bytes,") == std::string::npos)
+	 RangesAllowed = false;
+      return true;
+   }
+
    return true;
 }
 									/*}}}*/
@@ -252,6 +261,7 @@ void ServerState::Reset(bool const Everything)				/*{{{*/
    if (Everything)
    {
       Persistent = false; Pipeline = false; PipelineAllowed = true;
+      RangesAllowed = true;
    }
 }
 									/*}}}*/

methods/server.h

@@ -51,6 +51,7 @@ struct ServerState
    enum {Header, Data} State;
    bool Persistent;
    bool PipelineAllowed;
+   bool RangesAllowed;
    std::string Location;
 
    // This is a Persistent attribute of the server itself.

test/integration/test-apt-update-transactions

@@ -82,7 +82,7 @@ testsetup 'file'
 changetowebserver
 webserverconfig 'aptwebserver::support::modified-since' 'false' "$1"
 webserverconfig 'aptwebserver::support::last-modified' 'false' "$1"  # curl is clever and sees hits here also
-webserverconfig 'aptwebserver::support::range' 'false' "$1"
+webserverconfig 'aptwebserver::response-header::Accept-Ranges' 'none' "$1"
 
 testsetup 'http'
 

test/integration/test-bug-lp1445239-download-loop

@@ -12,7 +12,6 @@ setupenvironment
 configarchitecture 'amd64'
 
 changetowebserver
-webserverconfig 'aptwebserver::support::range' 'true'
 
 TESTFILE='aptarchive/testfile'
 dd if=/dev/zero of=$TESTFILE bs=100k count=1 2>/dev/null

test/integration/test-partial-file-support

@@ -96,6 +96,7 @@ followuprequest() {
 
 testrun() {
 	webserverconfig 'aptwebserver::support::range' 'true'
+	webserverconfig 'aptwebserver::response-header::Accept-Ranges' 'bytes'
 	local DOWN='./downloaded/testfile'
 
 	copysource $TESTFILE 0 $DOWN
@@ -125,7 +126,11 @@ testrun() {
 	testdownloadfile 'old data' "${1}/testfile" "$DOWN" '='
 	testwebserverlaststatuscode '200' "$DOWNLOADLOG"
 
-	webserverconfig 'aptwebserver::support::range' 'false'
+	if [ "${1%%:*}" = 'https' ] && expr match "$1" "^.*/redirectme$" >/dev/null; then
+		webserverconfig 'aptwebserver::response-header::Accept-Ranges' 'none'
+	else
+		webserverconfig 'aptwebserver::support::range' 'false'
+	fi
 
 	copysource $TESTFILE 20 $DOWN
 	testdownloadfile 'no server support' "${1}/testfile" "$DOWN" '='
@@ -148,4 +153,5 @@ changetohttpswebserver
 serverconfigs "https://localhost:${APTHTTPSPORT}"
 
 webserverconfig 'aptwebserver::redirect::replace::/redirectme/' "https://localhost:${APTHTTPSPORT}/"
+serverconfigs "https://localhost:${APTHTTPSPORT}/redirectme"
 serverconfigs "http://localhost:${APTHTTPPORT}/redirectme"

test/integration/test-releasefile-verification

@@ -12,8 +12,6 @@ buildaptarchive
 setupflataptarchive
 changetowebserver
 
-webserverconfig 'aptwebserver::support::range' 'false'
-
 prepare() {
 	local DATE="${2:-now}"
 	if [ "$DATE" = 'now' ]; then

test/interactive-helper/aptwebserver.cc

@@ -717,6 +717,15 @@ static void * handleClient(void * voidclient)				/*{{{*/
 	       condition.clear();
 	    if (condition.empty() == false && strncmp(condition.c_str(), "bytes=", 6) == 0)
 	    {
+	       std::string ranges = ',' + _config->Find("aptwebserver::response-header::Accept-Ranges") + ',';
+	       ranges.erase(std::remove(ranges.begin(), ranges.end(), ' '), ranges.end());
+	       if (ranges.find(",bytes,") == std::string::npos)
+	       {
+		  // we handle it as an error here because we are a test server - a real one should just ignore it
+		  sendError(client, 400, *m, sendContent, "Client does range requests we don't support", headers);
+		  continue;
+	       }
+
 	       time_t cache;
 	       std::string ifrange;
 	       if (_config->FindB("aptwebserver::support::if-range", true) == true)