mirror of
https://github.com/servalproject/serval-dna.git
synced 2024-12-19 13:17:56 +00:00
305 lines
9.2 KiB
C
305 lines
9.2 KiB
C
/*
|
|
Serval Distributed Numbering Architecture (DNA)
|
|
Copyright (C) 2010 Paul Gardner-Stephen
|
|
|
|
This program is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU General Public License
|
|
as published by the Free Software Foundation; either version 2
|
|
of the License, or (at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include "serval.h"
|
|
|
|
struct reachable_peer {
|
|
unsigned char addr_len;
|
|
unsigned char addr[32];
|
|
unsigned char tq_avg;
|
|
};
|
|
|
|
#ifndef RTF_UP
|
|
/* Keep this in sync with /usr/src/linux/include/linux/route.h */
|
|
#define RTF_UP 0x0001 /* route usable */
|
|
#define RTF_GATEWAY 0x0002 /* destination is a gateway */
|
|
#define RTF_HOST 0x0004 /* host entry (net otherwise) */
|
|
#define RTF_REINSTATE 0x0008 /* reinstate route after tmout */
|
|
#define RTF_DYNAMIC 0x0010 /* created dyn. (by redirect) */
|
|
#define RTF_MODIFIED 0x0020 /* modified dyn. (by redirect) */
|
|
#define RTF_MTU 0x0040 /* specific MTU for this route */
|
|
#ifndef RTF_MSS
|
|
#define RTF_MSS RTF_MTU /* Compatibility :-( */
|
|
#endif
|
|
#define RTF_WINDOW 0x0080 /* per route window clamping */
|
|
#define RTF_IRTT 0x0100 /* Initial round trip time */
|
|
#define RTF_REJECT 0x0200 /* Reject route */
|
|
#endif
|
|
|
|
int readRoutingTable(struct in_addr peers[],int *peer_count,int peer_max){
|
|
char devname[64];
|
|
unsigned long d, g, m;
|
|
int flgs, ref, use, metric, mtu, win, ir;
|
|
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Reading routing table\n");
|
|
|
|
FILE *fp = fopen("/proc/net/route","r");
|
|
if (!fp) return -1;
|
|
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Skipping line\n");
|
|
if (fscanf(fp, "%*[^\n]\n") < 0)
|
|
goto ERROR;
|
|
|
|
while(1){
|
|
int r;
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Reading next route\n");
|
|
r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
|
|
devname, &d, &g, &flgs, &ref, &use, &metric, &m,
|
|
&mtu, &win, &ir);
|
|
|
|
if (r != 11) {
|
|
if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"eof\n");
|
|
break;
|
|
}
|
|
ERROR:
|
|
fclose(fp);
|
|
return setReason("Unable to parse routing table");
|
|
}
|
|
|
|
if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Skipping down interface %s\n",devname);
|
|
continue;
|
|
}
|
|
|
|
if (m!=0xFFFFFFFF){
|
|
/* Netmask indicates a network, so calculate broadcast address */
|
|
d=(d&m)|(0xffffffff^m);
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Adding broadcast address %08lx\n",d);
|
|
}
|
|
|
|
if (*peer_count<peer_max) peers[(*peer_count)++].s_addr=d;
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Found peer %08lx from routing table\n",d);
|
|
}
|
|
fclose(fp);
|
|
return 0;
|
|
}
|
|
|
|
int readArpTable(struct in_addr peers[],int *peer_count,int peer_max){
|
|
unsigned long d;
|
|
int q1,q2,q3,q4;
|
|
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Reading ARP table\n");
|
|
|
|
FILE *fp = fopen("/proc/net/arp","r");
|
|
if (!fp) return -1;
|
|
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Skipping line\n");
|
|
if (fscanf(fp, "%*[^\n]\n") < 0)
|
|
goto ERROR;
|
|
|
|
while(1){
|
|
int r;
|
|
r = fscanf(fp, "%d.%d.%d.%d%*[^\n]\n",
|
|
&q1,&q2,&q3,&q4);
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Reading next arp entry (r=%d, %d.%d.%d.%d)\n",r,q1,q2,q3,q4);
|
|
|
|
d = (q1&0xff)
|
|
+((q2&0xff)<<8)
|
|
+((q3&0xff)<<16)
|
|
+((q4&0xff)<<24);
|
|
|
|
if (r != 4) {
|
|
if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"eof\n");
|
|
break;
|
|
}
|
|
ERROR:
|
|
fclose(fp);
|
|
return setReason("Unable to parse arp table");
|
|
}
|
|
|
|
if (*peer_count<peer_max) peers[(*peer_count)++].s_addr=d;
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Found peer %08lx from ARP table\n",d);
|
|
}
|
|
fclose(fp);
|
|
return 0;
|
|
}
|
|
|
|
int readBatmanPeerFile(char *file_path,struct in_addr peers[],int *peer_count,int peer_max)
|
|
{
|
|
/* Shiny new code to read the flat file containing peer list */
|
|
FILE *f;
|
|
unsigned int offset=0;
|
|
unsigned int timestamp=0;
|
|
struct reachable_peer p;
|
|
|
|
f=fopen(file_path,"r");
|
|
if (!f) {
|
|
fprintf(stderr,"Failed to open peer list file `%s'\n",file_path);
|
|
return -1;
|
|
}
|
|
|
|
if (fread(&offset,sizeof(offset),1,f)!=1) {
|
|
fprintf(stderr,"Failed to read peer list offset from `%s'\n",file_path);
|
|
fclose(f); return -1; }
|
|
offset=ntohl(offset);
|
|
|
|
if (fseek(f,offset,SEEK_SET)) {
|
|
fprintf(stderr,"Failed to seek to peer list offset 0x%x in `%s'\n",offset,file_path);
|
|
fclose(f); return -1; }
|
|
|
|
if (fread(×tamp,sizeof(timestamp),1,f)!=1) {
|
|
fprintf(stderr,"Failed to read peer list timestamp from `%s'\n",file_path);
|
|
fclose(f); return -1; }
|
|
timestamp=ntohl(timestamp);
|
|
|
|
if (timestamp<(time(0)-3)) {
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Ignoring stale BATMAN peer list (%d seconds old)\n",(int)(time(0)-timestamp));
|
|
fclose(f);
|
|
return -1;
|
|
}
|
|
|
|
while(fread(&p,sizeof(p),1,f)==1)
|
|
{
|
|
struct in_addr i;
|
|
if (!p.addr_len) break;
|
|
i.s_addr=*(unsigned int *)&p.addr[0];
|
|
if (*peer_count<peer_max) peers[(*peer_count)++]=i;
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Found BATMAN peer '%s'\n",inet_ntoa(i));
|
|
}
|
|
|
|
fclose(f);
|
|
return 0;
|
|
}
|
|
|
|
int getBatmanPeerList(char *socket_path,struct in_addr peers[],int *peer_count,int peer_max)
|
|
{
|
|
#ifdef WIN32
|
|
return -1;
|
|
#else
|
|
int sock;
|
|
struct sockaddr_un socket_address;
|
|
unsigned char buf[16384]; /* big enough for a gigabit jumbo frame or loopback godzilla-gram */
|
|
int ofs=0;
|
|
int bytes=0;
|
|
struct pollfd fds;
|
|
char cmd[30];
|
|
int notDone=1;
|
|
int res;
|
|
int tries=0;
|
|
|
|
askagain:
|
|
|
|
/* Make socket */
|
|
sock=socket(AF_LOCAL,SOCK_STREAM,0);
|
|
memset(&socket_address,0,sizeof(struct sockaddr_un));
|
|
socket_address.sun_family=AF_LOCAL;
|
|
if (strlen(socket_path)>256) return setReason("BATMAN socket path too long");
|
|
strcpy(socket_address.sun_path,socket_path);
|
|
|
|
/* Connect the socket */
|
|
if (connect(sock,(struct sockaddr*)&socket_address,sizeof(socket_address))<0)
|
|
return setReason("connect() to BATMAN socket failed.");
|
|
|
|
memset(&cmd[0],0,30);
|
|
snprintf(cmd,30,"d:%c",1);
|
|
if (write(sock,cmd,30)!=30)
|
|
{ close(sock); return setReason("write() command failed to BATMAN socket."); }
|
|
|
|
fds.fd=sock;
|
|
fds.events=POLLIN;
|
|
|
|
getmore:
|
|
|
|
while(notDone)
|
|
{
|
|
switch (poll(&fds,1,1500)) {
|
|
case 1: /* Excellent - we have a response */ break;
|
|
case 0: if (debug&DEBUG_PEERS) fprintf(stderr,"BATMAN did not respond to peer enquiry.\n");
|
|
close(sock);
|
|
if (tries++<=3) goto askagain;
|
|
return setReason("No response from BATMAN.");
|
|
default: /* some sort of error, e.g., lost connection */
|
|
close(sock);
|
|
return setReason("poll() of BATMAN socket failed.");
|
|
}
|
|
|
|
res=read(sock,&buf[bytes],16383-bytes); close(sock);
|
|
ofs=0;
|
|
if (res<1) {
|
|
if (bytes)
|
|
{
|
|
/* Got a partial response, then a dead line.
|
|
Should probably ask again unless we have tried too many times.
|
|
*/
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Trying again after cold drop.\n");
|
|
close(sock);
|
|
bytes=0;
|
|
if (tries++<=3) goto askagain;
|
|
else return setReason("failed to read() from BATMAN socket (too many tries).");
|
|
}
|
|
return setReason("failed to read() from BATMAN socket.");
|
|
}
|
|
if (!res) return 0;
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"BATMAN has responded with %d bytes.\n",res);
|
|
|
|
if (debug&DEBUG_PEERS) dump("BATMAN says",&buf[bytes],res);
|
|
|
|
if (res<80 /*||buf[bytes]!='B' -- turns out we can't rely on this, either */
|
|
||buf[bytes+res-1]!=0x0a||buf[bytes+res-4]!='E')
|
|
{
|
|
/* Jolly BATMAN on Android sometimes sends us bung packets from time to
|
|
time. Sometimes it is fragmenting, other times it is just plain
|
|
odd.
|
|
If this happens, we should just ask again.
|
|
We should also try to reassemble fragments.
|
|
|
|
Sometimes we get cold-drops and resumes, too. Yay.
|
|
*/
|
|
if (buf[bytes+res-4]!='E') {
|
|
/* no end marker, so try adding record to the end. */
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Data has no end marker, accumulating.\n");
|
|
bytes+=res;
|
|
goto getmore;
|
|
}
|
|
close(sock);
|
|
goto askagain;
|
|
}
|
|
bytes+=res;
|
|
|
|
while(ofs<bytes)
|
|
{
|
|
if(debug&DEBUG_PEERS) fprintf(stderr,"New line @ %d\n",ofs);
|
|
/* Check for IP address of peers */
|
|
if (isdigit(buf[ofs]))
|
|
{
|
|
int i;
|
|
for(i=0;ofs+i<bytes;i++)
|
|
if (buf[i+ofs]==' ') {
|
|
buf[i+ofs]=0;
|
|
if (*peer_count<peer_max) peers[(*peer_count)++].s_addr=inet_addr((char *)&buf[ofs]);
|
|
if (debug&DEBUG_PEERS) fprintf(stderr,"Found BATMAN peer '%s'\n",&buf[ofs]);
|
|
buf[ofs+i]=' ';
|
|
break;
|
|
}
|
|
}
|
|
/* Check for end of transmission */
|
|
if (buf[ofs]=='E') { notDone=0; }
|
|
|
|
/* Skip to next line */
|
|
while(buf[ofs]>=' '&&(ofs<bytes)) ofs++;
|
|
while(buf[ofs]<' '&&(ofs<bytes)) ofs++;
|
|
}
|
|
bytes=0;
|
|
}
|
|
return 0;
|
|
#endif
|
|
}
|