diff options
Diffstat (limited to 'src/DefaultBtContext.cc')
| -rw-r--r-- | src/DefaultBtContext.cc | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/src/DefaultBtContext.cc b/src/DefaultBtContext.cc index b5f3ad28..29c748ce 100644 --- a/src/DefaultBtContext.cc +++ b/src/DefaultBtContext.cc @@ -40,6 +40,8 @@ #include "DlAbortEx.h" #include "ShaVisitor.h" #include "Util.h" +#include "MessageDigestHelper.h" +#include "a2netcompat.h" #include <libgen.h> DefaultBtContext::DefaultBtContext():_peerIdPrefix("-aria2-") {} @@ -245,3 +247,39 @@ int32_t DefaultBtContext::getPieceLength() const { int32_t DefaultBtContext::getNumPieces() const { return numPieces; } + +Integers DefaultBtContext::computeFastSet(const string& ipaddr, int32_t fastSetSize) +{ + Integers fastSet; + struct in_addr saddr; + if(inet_aton(ipaddr.c_str(), &saddr) == 0) { + abort(); + } + unsigned char tx[24]; + memcpy(tx, (void*)&saddr.s_addr, 4); + if((tx[0] & 0x80) == 0 || (tx[0] & 0x40) == 0) { + tx[2] = 0x00; + tx[3] = 0x00; + } else { + tx[3] = 0x00; + } + memcpy(tx+4, infoHash, 20); + unsigned char x[20]; + MessageDigestHelper::digest(x, sizeof(x), "sha1", tx, 24); + while((int32_t)fastSet.size() < fastSetSize) { + for(int32_t i = 0; i < 5 && (int32_t)fastSet.size() < fastSetSize; i++) { + int32_t j = i*4; + uint32_t ny; + memcpy(&ny, x+j, 4); + uint32_t y = ntohl(ny); + int32_t index = y%numPieces; + if(find(fastSet.begin(), fastSet.end(), index) == fastSet.end()) { + fastSet.push_back(index); + } + } + unsigned char temp[20]; + MessageDigestHelper::digest(temp, sizeof(temp), "sha1", x, sizeof(x)); + memcpy(x, temp, sizeof(x)); + } + return fastSet; +} |