ExternalVendorCode/serval-dna
1
0
Fork 0
mirror of https://github.com/servalproject/serval-dna.git synced 2024-12-22 14:32:25 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

sending MDP Rhizome replies in response to requests now occurs,

Browse Source 
and replies are received, but not yet parsed.
This commit is contained in:
gardners 2012-11-30 21:50:17 +10:30
parent 1be28246e4
commit 1912f24da4
1 changed files with 87 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

93
overlay_mdp_services.c
View File

@ -36,12 +36,92 @@ int overlay_mdp_service_rhizomerequest(overlay_mdp_frame *mdp)
DEBUGF("bundle ID = %s",alloca_tohex_bid(&mdp->out.payload[0]));
DEBUGF("manifest version = 0x%llx",
read_uint64(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES]));
DEBUGF("file offset = 0x%llx",
read_uint64(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8]));
DEBUGF("bitmap = 0x%08x",
read_uint32(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8+8]));
DEBUGF("block length = %d",
read_uint16(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8+8+4]));
uint64_t fileOffset=
read_uint64(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8]);
DEBUGF("file offset = 0x%llx",fileOffset);
uint32_t bitmap=
read_uint32(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8+8]);
DEBUGF("bitmap = 0x%08x",bitmap);
uint16_t blockLength=
read_uint16(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES+8+8+4]);
DEBUGF("block length = %d",blockLength);
if (blockLength>300) RETURN(-1);
/* Find manifest that corresponds to BID and version.
If we don't have this combination, then do nothing.
If we do have the combination, then find the associated file,
and open the blob so that we can send some of it.
TODO: If we have a newer version of the manifest, and the manifest is a
journal, then the newer version is okay to use to service this request.
*/
long long row_id=-1;
if (sqlite_exec_int64(&row_id, "SELECT rowid FROM FILES WHERE id IN (SELECT filehash FROM MANIFESTS WHERE manifests.version=%lld AND manifests.id='%s');",
read_uint64(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES]),
alloca_tohex_bid(&mdp->out.payload[0])) < 1)
{
DEBUGF("Couldn't find stored file.");
RETURN(-1);
}
DEBUGF("manifest file row_id = %lld",row_id);
sqlite3_blob *blob=NULL;
int ret=sqlite3_blob_open(rhizome_db, "main", "files", "data",
row_id, 0 /* read only */, &blob);
if (ret!=SQLITE_OK)
{
DEBUGF("Failed to open blob: %s",sqlite3_errmsg(rhizome_db));
RETURN(-1);
}
int blob_bytes=sqlite3_blob_bytes(blob);
if (blob_bytes<fileOffset) {
sqlite3_blob_close(blob); blob=NULL;
RETURN(-1);
}
overlay_mdp_frame reply;
bzero(&reply,sizeof(reply));
// Reply is broadcast, so we cannot authcrypt, and signing is too time consuming
// for low devices. The result is that an attacker can prevent rhizome transfers
// if they want to by injecting fake blocks. The alternative is to not broadcast
// back replies, and then we can authcrypt.
reply.packetTypeAndFlags=MDP_TX|MDP_NOSIGN|MDP_NOCRYPT;
reply.out.ttl=1;
bcopy(my_subscriber->sid,reply.out.src.sid,SID_SIZE);
// send replies to broadcast so that others can hear blocks and record them
// (not that preemptive listening is implemented yet).
reply.out.src.port=MDP_PORT_RHIZOME_RESPONSE;
memset(reply.out.dst.sid,0xff,SID_SIZE);
reply.out.dst.port=MDP_PORT_RHIZOME_RESPONSE;
reply.out.queue=OQ_ORDINARY;
reply.out.payload[0]='B'; // reply contains blocks
// include 16 bytes of BID prefix for identification
bcopy(&mdp->out.payload[0],&reply.out.payload[0],16);
// and version of manifest
bcopy(&mdp->out.payload[RHIZOME_MANIFEST_ID_BYTES],
&reply.out.payload[16],8);
int i;
for(i=0;i<32;i++)
if (!(bitmap&(1<<(31-i))))
{
// calculate and set offset of block
uint64_t blockOffset=fileOffset+i*blockLength;
write_uint64(&reply.out.payload[16+8],blockOffset);
// work out how many bytes to read
int blockBytes=blob_bytes-blockOffset;
if (blockBytes>blockLength) blockBytes=blockLength;
// read data for block
if (blob_bytes>=blockOffset) {
sqlite3_blob_read(blob,&reply.out.payload[16+8+8],
blockBytes,0);
reply.out.payload_length=16+8+8+blockBytes;
}
// send packet
overlay_mdp_dispatch(&reply,0 /* system generated */, NULL,0);
}
sqlite3_blob_close(blob); blob=NULL;
RETURN(-1);
}
@ -49,6 +129,7 @@ int overlay_mdp_service_rhizomerequest(overlay_mdp_frame *mdp)
int overlay_mdp_service_rhizomeresponse(overlay_mdp_frame *mdp)
{
IN();
DEBUGF("Someone sent me a rhizome REPLY via MDP");
RETURN(-1);
}