unsigned char *overlay_get_my_sid()
{
/* Make sure we can find our SID */
int zero=0;
if (!findHlr(hlr,&zero,NULL,NULL)) { WHY("Could not find first entry in HLR"); return NULL; }
return &hlr[zero+4];
}
int createHlr(char *did,char *sid) {
int i;
int record_offset=0;
/* Generate random SID */
for(i=0;i<64;i++) sid[i]=hexdigit[random()&0xf]; sid[64]=0;
if (debug>1) fprintf(stderr,"Creating new HLR entry with sid %s\n",sid);
/* Find first free byte of HLR */
findHlr(hlr,&record_offset,NULL,NULL);
if (record_offset>=hlr_size)
{
/* No space */
return setReason("No space in HLR for a new record");
}
else
{
/* We have found space, but is it enough? */
int bytes=hlr_size-record_offset;
if (bytes<1024) return setReason("<1KB space in HLR");
/* Write shiny fresh new record.
32bit - record length
32 bytes - SID
Total length = 4+32=36 bytes.
*/
if (stowSid(hlr,record_offset+4,sid)) return setReason("Could not store SID in new HLR entry");
/* Write length last of all to make entry valid */
hlr[record_offset]=0;
hlr[record_offset+1]=0;
hlr[record_offset+2]=0;
hlr[record_offset+3]=36;
/* Store the DID */
{
unsigned char packeddid[DID_MAXSIZE];
int pdidlen=0;
stowDid(packeddid,&pdidlen,did);
/* Work out reduced length of DID */
for(pdidlen=1;pdidlen<DID_MAXSIZE;pdidlen++) if (packeddid[pdidlen-1]==0xff) break;
hlrSetVariable(hlr,record_offset,VAR_DIDS,0x00,packeddid,pdidlen);
}
if (debug) fprintf(stderr,"Created new 36 byte HLR record for DID=[%s] @ 0x%x with SID=[%s]\n",
did,record_offset,sid);
if (debug>2) dump("after HLR create",&hlr[0],256);
return 0;
}
return setReason("Unreachable code turned out not to be");
}
int processRequest(unsigned char *packet,int len,
struct sockaddr *sender,int sender_len,
unsigned char *transaction_id,char *did,char *sid)
{
/* Find HLR entry by DID or SID, unless creating */
int ofs,rofs=0;
int records_searched=0;
int prev_pofs=0;
int pofs=OFS_PAYLOAD;
while(pofs<len)
{
if (debug>1) fprintf(stderr," processRequest: len=%d, pofs=%d, pofs_prev=%d\n",len,pofs,prev_pofs);
/* Avoid infinite loops */
if (pofs<=prev_pofs) break;
prev_pofs=pofs;
if (packet[pofs]==ACTION_CREATEHLR)
{
/* Creating an HLR requires an initial DID number and definately no SID -
you can't choose a SID. */
if (debug>1) fprintf(stderr,"Creating a new HLR record. did='%s', sid='%s'\n",did,sid);
if (!did[0]) return respondSimple(NULL,ACTION_DECLINED,NULL,0,transaction_id);
if (sid[0]) return respondSimple(sid,ACTION_DECLINED,NULL,0,transaction_id);
if (debug>1) fprintf(stderr,"Verified that create request supplies DID but not SID\n");
{
char sid[128];
/* make HLR with new random SID and initial DID */
if (!createHlr(did,sid))
return respondSimple(sid,ACTION_OKAY,NULL,0,transaction_id);
else
return respondSimple(NULL,ACTION_DECLINED,NULL,0,transaction_id);
}
pofs+=1;
pofs+=1+SID_SIZE;
}
else
{
switch(packet[pofs])
{
case ACTION_PAD: /* Skip padding */
pofs++;
pofs+=1+packet[pofs];
break;
case ACTION_EOT: /* EOT */
pofs=len;
break;
case ACTION_STATS:
/* short16 variable id,
int32 value */
{
pofs++;
short field=packet[pofs+1]+(packet[pofs]<<8);
int value=packet[pofs+5]+(packet[pofs+4]<<8)+(packet[pofs+3]<<16)+(packet[pofs+2]<<24);
pofs+=6;
if (instrumentation_file)
{
if (!i_f) { if (strcmp(instrumentation_file,"-")) i_f=fopen(instrumentation_file,"a"); else i_f=stdout; }
if (i_f) fprintf(i_f,"%ld:%08x:%d:%d\n",time(0),*(unsigned int *)&sender->sa_data[0],field,value);
if (i_f) fflush(i_f);
}
}
break;
case ACTION_DIGITALTELEGRAM:
// Unpack SMS message.
{
char emitterPhoneNumber[256];
char message[256];
pofs++;
char messageType = packet[pofs];
pofs++;
char emitterPhoneNumberLen = packet[pofs];
pofs++;
char messageLen = packet[pofs];
pofs++;
strncpy(emitterPhoneNumber, (const char*)packet+pofs, emitterPhoneNumberLen);
pofs+=emitterPhoneNumberLen;
strncpy(message, (const char*)packet+pofs, messageLen);
pofs+=messageLen;
// Check if I'm the recipient
// Send SMS to android
char amCommand[576]; // 64 char + 2*256(max) char = 576
sprintf(amCommand, "am broadcast -a org.servalproject.DT -e number \"%s\" -e content \"%s\"", emitterPhoneNumber, message);
int exitcode = printf(amCommand);
//int exitcode = system(amCommand);
}
break;
case ACTION_SET:
ofs=0;
if (debug>1) fprintf(stderr,"Looking for hlr entries with sid='%s' / did='%s'\n",sid,did);
if ((!sid)||(!sid[0])) {
setReason("You can only set variables by SID");
return respondSimple(NULL,ACTION_ERROR,(unsigned char *)"SET requires authentication by SID",0,transaction_id);
}
while(findHlr(hlr,&ofs,sid,did))
{
int itemId,instance,start_offset,bytes,flags;
unsigned char value[9000],oldvalue[65536];
int oldr,oldl;
if (debug>1) fprintf(stderr,"findHlr found a match for writing at 0x%x\n",ofs);
if (debug>2) hlrDump(hlr,ofs);
/* XXX consider taking action on this HLR
(check PIN first depending on the action requested) */
/* XXX Doesn't verify PIN authentication */
/* Get write request */
pofs++; rofs=pofs;
if (extractRequest(packet,&pofs,len,
&itemId,&instance,value,
&start_offset,&bytes,&flags))
{
setReason("Could not extract ACTION_SET request");
return
respondSimple(NULL,ACTION_ERROR,(unsigned char *)"Mal-formed SET request",0,transaction_id);
}
/* Get the stored value */
oldl=65536;
oldr=hlrGetVariable(hlr,ofs,itemId,instance,oldvalue,&oldl);
if (oldr) {
if (flags==SET_NOREPLACE) {
oldl=0;
} else {
setReason("Tried to SET_NOCREATE/SET_REPLACE a non-existing value");
return
respondSimple(NULL,ACTION_ERROR,
(unsigned char *)"Cannot SET NOCREATE/REPLACE a value that does not exist",
0,transaction_id);
}
} else {
if (flags==SET_NOREPLACE) {
setReason("Tried to SET_NOREPLACE an existing value");
if (debug>1) dump("Existing value",oldvalue,oldl);
return
respondSimple(NULL,ACTION_ERROR,
(unsigned char *)"Cannot SET NOREPLACE; a value exists",
0,transaction_id);
}
}
/* Replace the changed portion of the stored value */
if ((start_offset+bytes)>oldl) {
bzero(&oldvalue[oldl],start_offset+bytes-oldl);
oldl=start_offset+bytes;
}
bcopy(&value[0],&oldvalue[start_offset],bytes);
/* Write new value back */
if (hlrSetVariable(hlr,ofs,itemId,instance,oldvalue,oldl))
{
setReason("Failed to write variable");
return
respondSimple(NULL,ACTION_ERROR,(unsigned char *)"Failed to SET variable",0,transaction_id);
}
if (debug>2) { fprintf(stderr,"HLR after writing:\n"); hlrDump(hlr,ofs); }
/* Reply that we wrote the fragment */
respondSimple(sid,ACTION_WROTE,&packet[rofs],6,
transaction_id);
/* Advance to next record and keep searching */
if (nextHlr(hlr,&ofs)) break;
}
break;
case ACTION_GET:
{
/* Limit transfer size to MAX_DATA_BYTES, plus an allowance for variable packing. */
unsigned char data[MAX_DATA_BYTES+16];
int dlen=0;
int sendDone=0;
int var_id=packet[pofs+1];
int instance=packet[pofs+2];
int offset=(packet[pofs+3]<<8)+packet[pofs+4];
char *hlr_sid=NULL;
pofs+=7;
if (debug>2) dump("Request bytes",&packet[pofs],8);
if (debug>1) fprintf(stderr,"Processing ACTION_GET (var_id=%02x, instance=%02x, pofs=0x%x, len=%d)\n",var_id,instance,pofs,len);
ofs=0;
if (debug>1) fprintf(stderr,"Looking for hlr entries with sid='%s' / did='%s'\n",sid?sid:"null",did?did:"null");
while(1)
{
struct hlrentry_handle *h;
// if an empty did was passed in, get results from all hlr records
if (*sid || *did){
if (!findHlr(hlr,&ofs,sid,did)) break;
if (debug>1) fprintf(stderr,"findHlr found a match @ 0x%x\n",ofs);
}
if (debug>2) hlrDump(hlr,ofs);
/* XXX consider taking action on this HLR
(check PIN first depending on the action requested) */
/* Form a reply packet containing the requested data */
if (instance==0xff) instance=-1;
/* Step through HLR to find any matching instances of the requested variable */
h=openhlrentry(hlr,ofs);
if (debug>1) fprintf(stderr,"openhlrentry(hlr,%d) returned %p\n",ofs,h);
while(h)
{
/* Is this the variable? */
if (debug>2) fprintf(stderr," considering var_id=%02x, instance=%02x\n",
h->var_id,h->var_instance);
if (h->var_id==var_id)
{
if (h->var_instance==instance||instance==-1)
{
if (debug>1) fprintf(stderr,"Sending matching variable value instance (instance #%d), value offset %d.\n",
h->var_instance,offset);
// only send each value when the *next* record is found, that way we can easily stamp the last response with DONE
if (sendDone>0)
respondSimple(hlr_sid,ACTION_DATA,data,dlen,transaction_id);
dlen=0;
if (packageVariableSegment(data,&dlen,h,offset,MAX_DATA_BYTES+16))
return setReason("packageVariableSegment() failed.");
hlr_sid=hlrSid(hlr,ofs);
sendDone++;
}
else
if (debug>2) fprintf(stderr,"Ignoring variable instance %d (not %d)\n",
h->var_instance,instance);
}
else
if (debug>2) fprintf(stderr,"Ignoring variable ID %d (not %d)\n",
h->var_id,var_id);
h=hlrentrygetent(h);
}
/* Advance to next record and keep searching */
if (nextHlr(hlr,&ofs)) break;
}
if (sendDone)
{
data[dlen++]=ACTION_DONE;
data[dlen++]=sendDone&0xff;
respondSimple(hlr_sid,ACTION_DATA,data,dlen,transaction_id);
}
if (gatewayuri&&(var_id==VAR_LOCATIONS)&&did&&strlen(did))
{
/* We are a gateway, so offer connection via the gateway as well */
unsigned char data[MAX_DATA_BYTES+16];
int dlen=0;
struct hlrentry_handle fake;
unsigned char uri[1024];
/* Turn gateway into full URI including extension */
snprintf((char *)uri,1024,"4101*%s@%s",did,gatewayuri);
fake.value_len=strlen((char *)uri);
fake.var_id=var_id;
fake.value=uri;
if (packageVariableSegment(data,&dlen,&fake,offset,MAX_DATA_BYTES+16))
return setReason("packageVariableSegment() of gateway URI failed.");
respondSimple(hlrSid(hlr,0),ACTION_DATA,data,dlen,transaction_id);
}
}
break;
default:
setReason("Asked to perform unsupported action");
if (debug) fprintf(stderr,"Packet offset = 0x%x\n",pofs);
if (debug) dump("Packet",packet,len);
return -1;
}
}
}
if (debug>1) fprintf(stderr,"Searched %d HLR entries.\n",records_searched);
return 0;
}
