/*
* pcap-septel.c: Packet capture interface for Intel/Septel card.
*
* The functionality of this code attempts to mimic that of pcap-linux as much
* as possible. This code is compiled in several different ways depending on
* whether SEPTEL_ONLY and HAVE_SEPTEL_API are defined. If HAVE_SEPTEL_API is
* not defined it should not get compiled in, otherwise if SEPTEL_ONLY is
* defined then the 'septel_' function calls are renamed to 'pcap_'
* equivalents. If SEPTEL_ONLY is not defined then nothing is altered - the
* septel_ functions will be called as required from their
* pcap-linux/equivalents.
*
* Authors: Gilbert HOYEK (gil_hoyek@hotmail.com), Elias M. KHOURY
* (+961 3 485243)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/param.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "pcap-int.h"
#include <ctype.h>
#include <netinet/in.h>
#include <sys/mman.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include <msg.h>
#include <ss7_inc.h>
#include <sysgct.h>
#include <pack.h>
#include <system.h>
#include "pcap-septel.h"
static int septel_setfilter(pcap_t *p, struct bpf_program *fp);
static int septel_stats(pcap_t *p, struct pcap_stat *ps);
static int septel_setnonblock(pcap_t *p, int nonblock, char *errbuf);
/*
* Private data for capturing on Septel devices.
*/
struct pcap_septel {
struct pcap_stat stat;
}
/*
* Read at most max_packets from the capture queue and call the callback
* for each of them. Returns the number of packets handled, -1 if an
* error occured, or -2 if we were told to break out of the loop.
*/
static int septel_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) {
struct pcap_septel *ps = p->priv;
HDR *h;
MSG *m;
int processed = 0 ;
int t = 0 ;
/* identifier for the message queue of the module(upe) from which we are capturing
* packets.These IDs are defined in system.txt . By default it is set to 0x2d
* so change it to 0xdd for technical reason and therefore the module id for upe becomes:
* LOCAL 0xdd * upe - Example user part task */
unsigned int id = 0xdd;
/* process the packets */
do {
unsigned short packet_len = 0;
int caplen = 0;
int counter = 0;
struct pcap_pkthdr pcap_header;
u_char *dp ;
/*
* Has "pcap_breakloop()" been called?
*/
loop:
if (p->break_loop) {
/*
* Yes - clear the flag that indicates that
* it has, and return -2 to indicate that
* we were told to break out of the loop.
*/
p->break_loop = 0;
return -2;
}
/*repeat until a packet is read
*a NULL message means :
* when no packet is in queue or all packets in queue already read */
do {
/* receive packet in non-blocking mode
* GCT_grab is defined in the septel library software */
h = GCT_grab(id);
m = (MSG*)h;
/* a couter is added here to avoid an infinite loop
* that will cause our capture program GUI to freeze while waiting
* for a packet*/
counter++ ;
}
while ((m == NULL)&& (counter< 100)) ;
if (m != NULL) {
t = h->type ;
/* catch only messages with type = 0xcf00 or 0x8f01 corrsponding to ss7 messages*/
/* XXX = why not use API_MSG_TX_REQ for 0xcf00 and API_MSG_RX_IND
* for 0x8f01? */
if ((t != 0xcf00) && (t != 0x8f01)) {
relm(h);
goto loop ;
}
/* XXX - is API_MSG_RX_IND for an MTP2 or MTP3 message? */
dp = get_param(m);/* get pointer to MSG parameter area (m->param) */
packet_len = m->len;
caplen = p->snapshot ;
if (caplen > packet_len) {
caplen = packet_len;
}
/* Run the packet filter if there is one. */
if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
/* get a time stamp , consisting of :
*
* pcap_header.ts.tv_sec:
* ----------------------
* a UNIX format time-in-seconds when he packet was captured,
* i.e. the number of seconds since Epoch time (January 1,1970, 00:00:00 GMT)
*
* pcap_header.ts.tv_usec :
* ------------------------
* the number of microseconds since that second
* when the packet was captured
*/
(void)gettimeofday(&pcap_header.ts, NULL);
/* Fill in our own header data */
pcap_header.caplen = caplen;
pcap_header.len = packet_len;
/* Count the packet. */
ps->stat.ps_recv++;
/* Call the user supplied callback function */
callback(user, &pcap_header, dp);
processed++ ;
}
/* after being processed the packet must be
*released in order to receive another one */
relm(h);
}else
processed++;
}
while (processed < cnt) ;
return processed ;
}
static int
septel_inject(pcap_t *handle, const void *buf _U_, size_t size _U_)
{
strlcpy(handle->errbuf, "Sending packets isn't supported on Septel cards",
PCAP_ERRBUF_SIZE);
return (-1);
}
/*
* Activate a handle for a live capture from the given Septel device. Always pass a NULL device
* The promisc flag is ignored because Septel cards have built-in tracing.
* The timeout is also ignored as it is not supported in hardware.
*
* See also pcap(3).
*/
static pcap_t *septel_activate(pcap_t* handle) {
/* Initialize some components of the pcap structure. */
handle->linktype = DLT_MTP2;
handle->bufsize = 0;
/*
* "select()" and "poll()" don't work on Septel queues
*/
handle->selectable_fd = -1;
handle->read_op = septel_read;
handle->inject_op = septel_inject;
handle->setfilter_op = septel_setfilter;
handle->set_datalink_op = NULL; /* can't change data link type */
handle->getnonblock_op = pcap_getnonblock_fd;
handle->setnonblock_op = septel_setnonblock;
handle->stats_op = septel_stats;
return 0;
}
pcap_t *septel_create(const char *device, char *ebuf, int *is_ours) {
const char *cp;
pcap_t *p;
/* Does this look like the Septel device? */
cp = strrchr(device, '/');
if (cp == NULL)
cp = device;
if (strcmp(cp, "septel") != 0) {
/* Nope, it's not "septel" */
*is_ours = 0;
return NULL;
}
/* OK, it's probably ours. */
*is_ours = 1;
p = pcap_create_common(device, ebuf, sizeof (struct pcap_septel));
if (p == NULL)
return NULL;
p->activate_op = septel_activate;
return p;
}
static int septel_stats(pcap_t *p, struct pcap_stat *ps) {
struct pcap_septel *handlep = p->priv;
/*handlep->stat.ps_recv = 0;*/
/*handlep->stat.ps_drop = 0;*/
*ps = handlep->stat;
return 0;
}
int
septel_findalldevs(pcap_if_t **devlistp, char *errbuf)
{
return (pcap_add_if(devlistp,"septel",0,
"Intel/Septel device",errbuf));
}
/*
* Installs the given bpf filter program in the given pcap structure. There is
* no attempt to store the filter in kernel memory as that is not supported
* with Septel cards.
*/
static int septel_setfilter(pcap_t *p, struct bpf_program *fp) {
if (!p)
return -1;
if (!fp) {
strncpy(p->errbuf, "setfilter: No filter specified",
sizeof(p->errbuf));
return -1;
}
/* Make our private copy of the filter */
if (install_bpf_program(p, fp) < 0) {
snprintf(p->errbuf, sizeof(p->errbuf),
"malloc: %s", pcap_strerror(errno));
return -1;
}
return (0);
}
static int
septel_setnonblock(pcap_t *p, int nonblock, char *errbuf)
{
fprintf(errbuf, PCAP_ERRBUF_SIZE, "Non-blocking mode not supported on Septel devices");
return (-1);
}