ua1zbe
/
aprsc
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Drop incoming packets with -0 SSIDs in callsigns. Speedup in callsign 

checking (array reference instead of pointer math and referencing) and
stricter callsign syntax checks.
This commit is contained in:
Heikki Hannikainen 2013-04-09 18:33:12 +03:00
parent dd9b6c92c6
commit fca8f208e9
2 changed files with 70 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

104
src/incoming.c
View File

@ -510,20 +510,41 @@ static int digi_path_drop(char *via_start, char *path_end)
int check_invalid_src_dst(const char *call, int len)
{
const char *p = call;
const char *e = call + len;
//hlog(LOG_DEBUG, "check_invalid_src_dst: '%.*s'", len, call);
if (len < 1 || len > CALLSIGNLEN_MAX)
return -1;
while (p < e) {
/* alphanumeric and - */
if ((!isalnum(*p)) && *p != '-')
int i = 0;
/* go through callsign body */
while (i < len && call[i] != '-') {
/* alphanumeric */
if (!isalnum(call[i]))
return -1;
p++;
i++;
}
/* we're at end? */
if (i == len)
return 0;
/* We have an SSID. */
i++;
/* Check SSID length to be between 1 and 2 */
if (len - i > 2 || len == i)
return -1;
/* SSID of 0? */
if (call[i] == '0')
return -1;
while (i < len) {
if (!isalnum(call[i]))
return -1;
i++;
}
return 0;
@ -536,43 +557,48 @@ int check_invalid_src_dst(const char *call, int len)
static int check_invalid_path_callsign(const char *call, int len, int after_q)
{
const char *p = call;
const char *e = call + len;
//hlog(LOG_DEBUG, "check_invalid_src_dst: '%.*s'", len, call);
//hlog_packet(LOG_DEBUG, call, len, "check_invalid_path_callsign: ");
/* allow a '*' in the end, and don't check for it */
if (len > 1 && call[len-1] == '*')
len--;
/* only check for minimum length first - max length depends on
* if there's a * in the end
*/
if (len < 1)
return -1;
while (p < e) {
/* alphanumeric and - */
/* AND '*' is allowed in the end */
if ((!isalnum(*p)) && *p != '-' && !(*p == '*' && p == e-1)) {
//hlog(LOG_DEBUG, "check_invalid_path_callsign: invalid char '%c'", *p);
return -1;
}
p++;
}
if (*(p-1) == '*' && len <= CALLSIGNLEN_MAX+1) {
//hlog(LOG_DEBUG, "check_invalid_path_callsign: allowing len %d due to last *", len);
return 0;
}
/* too long? */
if (len > CALLSIGNLEN_MAX) {
// TODO: more specific test for IPv6 trace address
if (after_q && len == 32) {
//hlog_packet(LOG_DEBUG, call, len, "check_invalid_path_callsign: ipv6 address: ");
return 0;
}
hlog(LOG_DEBUG, "check_invalid_path_callsign: too long len %d", len);
if (len > CALLSIGNLEN_MAX && !(len == 32 && after_q))
return -1;
int i = 0;
/* go through callsign body */
while (i < len && call[i] != '-') {
/* alphanumeric */
if (!isalnum(call[i]))
return -1;
i++;
}
/* we're at end? */
if (i == len)
return 0;
/* We have an SSID. */
i++;
/* Check SSID length to be between 1 and 2 */
if (len - i > 2 || len == i)
return -1;
/* SSID of 0? */
if (call[i] == '0')
return -1;
while (i < len) {
if (!isalnum(call[i]))
return -1;
i++;
}
return 0;

5
tests/t/11misc-drops.t
View File

@ -77,6 +77,11 @@ my @pkts = (
"SRC2>DST,DIGI,qAX,$login:>Packet from unverified login according to qAX",
"SRC2>DST,DIGI,TCPXX,qAR,$login:>Packet from unverified login according to TCPXX in path",
"SRC2>DST,DIGI,TCPXX*,qAR,$login:>Packet from unverified login according to TCPXX* in path",
"SRC-0>DST,DIGI,qAR,$login:>should drop, -0 SSID in srccall",
"SRC->DST,DIGI-0,qAR,$login:>should drop, too short SSID in srccall",
"SRC-111>DST,DIGI-0,qAR,$login:>should drop, too long SSID in srccall",
"SRC>DST-0,DIGI,qAR,$login:>should drop, -0 SSID in dstcall",
"SRC>DST,DIGI-0,qAR,$login:>should drop, -0 SSID in viacall",
);
# send the packets