tcptable.c

Snmp（简单网管协议）软件包。

#else /*  defined(freebsd2) || defined(netbsd1) || defined(openbsd2) */
	while (inpcb.INP_NEXT_SYMBOL != (struct inpcb *) auto_nlist_value(TCP_SYMBOL))
#endif /*  defined(freebsd2) || defined(netbsd1) */
	{
		next = inpcb.INP_NEXT_SYMBOL;

		if((klookup((unsigned long)next, (char *)&inpcb, sizeof (inpcb)) == 0)) {
		    snmp_log_perror("TCP_Count_Connections - inpcb");
		    break;
		}
#if !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2))
		if (inpcb.INP_PREV_SYMBOL != prev) {	    /* ??? */
			sleep(1);
			goto Again;
		}
#endif /*  !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2)) */
		if (inet_lnaof(inpcb.inp_laddr) == INADDR_ANY) {
#if !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2))
			prev = next;
#endif /*  !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2)) */
			continue;
		}
		if(klookup((unsigned long)inpcb.inp_ppcb, (char *)&tcpcb, sizeof (tcpcb)) == 0) {
		    snmp_log_perror("TCP_Count_Connections - tcpcb");
		    break;
		}

		if ((tcpcb.t_state == TCPS_ESTABLISHED) ||
		    (tcpcb.t_state == TCPS_CLOSE_WAIT))
		    Established++;
#if !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2))
		prev = next;
#endif /*  !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2)) */
	}
	return(Established);
}
#endif

static struct inpcb tcp_inpcb, *tcp_prev;
#ifdef PCB_TABLE
static struct inpcb *tcp_next, *tcp_head;
#endif
#ifdef linux
static struct inpcb *inpcb_list;
#endif

#if defined(CAN_USE_SYSCTL) && defined(TCPCTL_PCBLIST)
static char *tcpcb_buf = NULL;
static struct xinpgen *xig = NULL;
#endif /* !defined(CAN_USE_SYSCTL) || !define(TCPCTL_PCBLIST) */

void TCP_Scan_Init (void)
{
#if !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST)
#ifdef PCB_TABLE
    struct inpcbtable table;
#endif
#ifndef linux
#ifdef PCB_TABLE
    auto_nlist(TCP_SYMBOL, (char *)&table, sizeof(table));
    tcp_head = tcp_prev = (struct inpcb *)&((struct inpcbtable *)auto_nlist_value(TCP_SYMBOL))->inpt_queue.cqh_first;
    tcp_next = table.inpt_queue.cqh_first;
#else	/* PCB_TABLE */
    auto_nlist(TCP_SYMBOL, (char *)&tcp_inpcb, sizeof(tcp_inpcb));
#if !(defined(freebsd2) || defined(netbsd1) || defined(openbsd2))
    tcp_prev = (struct inpcb *) auto_nlist_value(TCP_SYMBOL);
#endif
#endif	/* PCB_TABLE */
#else	/* linux */
    FILE *in;
    char line [256];
    struct inpcb **pp;
    struct timeval now;
    static unsigned long Time_Of_Last_Reload = 0;

    /*
     * save some cpu-cycles, and reload after 5 secs...
     */
    gettimeofday (&now, (struct timezone *) 0);
    if (Time_Of_Last_Reload + 5 > now.tv_sec)
      {
	tcp_prev = inpcb_list;
	return;
      }
    Time_Of_Last_Reload = now.tv_sec;


    if (! (in = fopen ("/proc/net/tcp", "r")))
      {
 snmp_log(LOG_ERR, "snmpd: cannot open /proc/net/tcp ...\n");
	tcp_prev = NULL;
	return;
      }

    /* free old chain: */
    while (inpcb_list)
      {
	struct inpcb *p = inpcb_list;
	inpcb_list = inpcb_list->INP_NEXT_SYMBOL;
	free (p);
      }

    /* scan proc-file and append: */

    pp = &inpcb_list;
    
    while (line == fgets (line, sizeof(line), in))
      {
	struct inpcb pcb, *nnew;
	static int linux_states [12] = { 0, 4, 2, 3, 6, 9, 10, 0, 5, 8, 1, 7 };
	int state, lp, fp, uid;

	if (6 != sscanf (line,
			 "%*d: %x:%x %x:%x %x %*X:%*X %*X:%*X %*X %d",
			 &pcb.inp_laddr.s_addr, &lp,
			 &pcb.inp_faddr.s_addr, &fp,
			 &state, &uid))
	  continue;

	pcb.inp_lport = htons ((unsigned short) lp);
	pcb.inp_fport = htons ((unsigned short) fp);

	pcb.inp_state = (state & 0xf) < 12 ? linux_states [state & 0xf] : 1;
	pcb.uid = uid;
    
	nnew = (struct inpcb *) malloc (sizeof (struct inpcb));
	if (nnew == NULL) break;
	*nnew = pcb;
	nnew->INP_NEXT_SYMBOL = 0;

	*pp = nnew;
	pp = & nnew->INP_NEXT_SYMBOL;
      }

    fclose (in);

    /* first entry to go: */
    tcp_prev = inpcb_list;

#endif /* linux */
#else /*  !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST) */
    {
	size_t len;
	int sname[] = { CTL_NET, PF_INET, IPPROTO_TCP, TCPCTL_PCBLIST };

	if (tcpcb_buf) {
	    free(tcpcb_buf);
	    tcpcb_buf = NULL;
	}
	xig = NULL;

	len = 0;
	if (sysctl(sname, 4, 0, &len, 0, 0) < 0) {
	    return;
	}
	if ((tcpcb_buf = malloc(len)) == NULL) {
	    return;
	}
	if (sysctl(sname, 4, tcpcb_buf, &len, 0, 0) < 0) {
	    free(tcpcb_buf);
	    tcpcb_buf = NULL;
	    return;
	}

	xig = (struct xinpgen *)tcpcb_buf;
	xig = (struct xinpgen *)((char *)xig + xig->xig_len);
	return;
    }
#endif /*  !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST) */
}

int TCP_Scan_Next(int *State,
		  struct inpcb *RetInPcb)
{
#if !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST)
	register struct inpcb *next;
#ifndef linux
	struct tcpcb tcpcb;

#ifdef PCB_TABLE
	if (tcp_next == tcp_head)
#elif defined(freebsd2) || defined(netbsd1) || defined(openbsd2)
	if (tcp_inpcb.INP_NEXT_SYMBOL == NULL ||
	    tcp_inpcb.INP_NEXT_SYMBOL == (struct inpcb *) auto_nlist_value(TCP_SYMBOL))
#else
	if (tcp_inpcb.INP_NEXT_SYMBOL == (struct inpcb *) auto_nlist_value(TCP_SYMBOL))
#endif
	{
	    return(0);	    /* "EOF" */
	}

#ifdef PCB_TABLE
	klookup((unsigned long)tcp_next, (char *)&tcp_inpcb, sizeof(tcp_inpcb));
	tcp_next = tcp_inpcb.inp_queue.cqe_next;
#else
	next = tcp_inpcb.INP_NEXT_SYMBOL;
	klookup((unsigned long)next, (char *)&tcp_inpcb, sizeof (tcp_inpcb));
#if !(defined(netbsd1) || defined(freebsd2)) || defined(openbsd2)
	if (tcp_inpcb.INP_PREV_SYMBOL != tcp_prev)	   /* ??? */
          return(-1); /* "FAILURE" */
#endif /*  !(defined(netbsd1) || defined(freebsd2) || defined(openbsd2)) */
#endif	/* PCB_TABLE */
	klookup ( (int)tcp_inpcb.inp_ppcb, (char *)&tcpcb, sizeof (tcpcb));
	*State = tcpcb.t_state;
#else /* linux */
	if (! tcp_prev)
	  return 0;

	tcp_inpcb = *tcp_prev;
	*State = tcp_inpcb.inp_state;
	next = tcp_inpcb.INP_NEXT_SYMBOL;
#endif

	*RetInPcb = tcp_inpcb;
#if !(defined(netbsd1) || defined(freebsd2) || defined(openbsd2))
	tcp_prev = next;
#endif
#else /*  !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST) */
	/* Are we done? */
	if ((xig == NULL) ||
	    (xig->xig_len <= sizeof(struct xinpgen)))
	    return(0);  
	
	*State = ((struct xtcpcb *)xig)->xt_tp.t_state;
	*RetInPcb = ((struct xtcpcb *)xig)->xt_inp;
	
	/* Prepare for Next read */
	xig = (struct xinpgen *)((char *)xig + xig->xig_len);
#endif /*  !defined(CAN_USE_SYSCTL) || !defined(TCPCTL_PCBLIST) */
	return(1);	/* "OK" */
}
#endif /* solaris2 */

#else /* WIN32 */
#include <iphlpapi.h>
WriteMethod writeTcpEntry;
MIB_TCPROW tcp_row;
u_char *
var_tcpEntry(struct variable *vp,
	     oid *name,
	     size_t *length,
	     int exact,
	     size_t *var_len,
	     WriteMethod **write_method)
{
    oid newname[MAX_OID_LEN], lowest[MAX_OID_LEN], *op;
    u_char *cp;
    int LowState = -1;
    static PMIB_TCPTABLE pTcpTable = NULL;
    DWORD status = NO_ERROR;
    DWORD dwActualSize = 0;
    UINT i;
    struct timeval now;
    static long Time_Of_Last_Reload = 0;

    memcpy( (char *)newname,(char *)vp->name, (int)vp->namelen * sizeof(oid));    

    /*
     * save some cpu-cycles, and reload after 5 secs...
     */
    gettimeofday (&now, (struct timezone *) 0);
    if ((Time_Of_Last_Reload + 5 <= now.tv_sec) || (pTcpTable == NULL) )
    {
        if(pTcpTable != NULL)
            free(pTcpTable);
        Time_Of_Last_Reload = now.tv_sec;
        /* query for buffer size needed */
        status = GetTcpTable(pTcpTable, &dwActualSize, TRUE);
        if (status == ERROR_INSUFFICIENT_BUFFER)
        {
            pTcpTable = (PMIB_TCPTABLE) malloc(dwActualSize);
            if(pTcpTable != NULL){  
                /* Get the sorted TCP table */
                status = GetTcpTable(pTcpTable, &dwActualSize, TRUE);
            }
        }
    }
   
    if(status == NO_ERROR)
    {
        for (i = 0; i < pTcpTable->dwNumEntries; ++i)
        {
	   
            cp = (u_char *)&pTcpTable->table[i].dwLocalAddr;
            op = newname + 10;
            *op++ = *cp++;
            *op++ = *cp++;
            *op++ = *cp++;
            *op++ = *cp++;
    
            newname[14] = ntohs((unsigned short)(0x0000FFFF & pTcpTable->table[i].dwLocalPort));

            cp = (u_char *)&pTcpTable->table[i].dwRemoteAddr;
            op = newname + 15;
            *op++ = *cp++;
            *op++ = *cp++;
            *op++ = *cp++;
            *op++ = *cp++;
        
            newname[19] = ntohs((unsigned short)(0x0000FFFF & pTcpTable->table[i].dwRemotePort));

            if (exact){
                if (snmp_oid_compare(newname, 20, name, *length) == 0){
                    memcpy( (char *)lowest,(char *)newname, 20 * sizeof(oid));
                    LowState = i;
                    break;  /* no need to search further */
                }
            } else {
                if (snmp_oid_compare(newname, 20, name, *length) > 0)
                 {
                    memcpy( (char *)lowest,(char *)newname, 20 * sizeof(oid));
                    LowState = i;
                    break; /* As the table is sorted, no need to search further */
                }
            }
        }
    }
    if ((LowState < 0) || (status != NO_ERROR))
      return(NULL);
    memcpy( (char *)name,(char *)lowest, (vp->namelen + 10) * sizeof(oid));
    *length = vp->namelen + 10;
    *write_method = 0;
    *var_len = sizeof(long);
    switch (vp->magic) {
        case TCPCONNSTATE:
            *write_method = writeTcpEntry;
            tcp_row = pTcpTable->table[i];
             return (u_char *) &pTcpTable->table[i].dwState;

        case TCPCONNLOCALADDRESS:
            return (u_char *) &pTcpTable->table[i].dwLocalAddr;
        case TCPCONNLOCALPORT:
            long_return = ntohs((unsigned short)(0x0000FFFF & pTcpTable->table[i].dwLocalPort));
            return (u_char *) &long_return;
        case TCPCONNREMADDRESS:
            return (u_char *) &pTcpTable->table[i].dwRemoteAddr;
        case TCPCONNREMPORT:
            long_return = ntohs((unsigned short)(0x0000FFFF & pTcpTable->table[i].dwRemotePort));
            return (u_char *) &long_return;
        default:
            DEBUGMSGTL(("snmpd", "unknown sub-id %d in var_tcpEntry\n", vp->magic));
    }
    return NULL;
}

int
writeTcpEntry(int action,	     
	    u_char *var_val,
	    u_char var_val_type,
	    size_t var_val_len,
	    u_char *statP,
	    oid *name,
	    size_t name_len)
{
   static int oldbuf;
   DWORD status = NO_ERROR;
   /* Only tcpConnState is writable */
   if((char)name[9] != 1)
     return SNMP_ERR_NOTWRITABLE;

    switch ( action ) {
	case RESERVE1:		/* Check values for acceptability */
	    if (var_val_type != ASN_INTEGER){
                snmp_log(LOG_ERR, "not integer\n");
		     return SNMP_ERR_WRONGTYPE;
	    }
	    if (var_val_len > sizeof(int)){
                snmp_log(LOG_ERR, "bad length\n");
		     return SNMP_ERR_WRONGLENGTH;
	    }	      
      if((int)(*var_val) != MIB_TCP_STATE_DELETE_TCB){
        snmp_log(LOG_ERR, "not supported admin state\n");
		    return SNMP_ERR_WRONGVALUE;
		}
	    break;

	case RESERVE2:		/* Allocate memory and similar resources */
		/* Using static strings, so nothing needs to be done */
    
	    break;

	case ACTION:		
    /* Save the old value, in case of UNDO */    
      oldbuf   = tcp_row.dwState;
      tcp_row.dwState = (int)*var_val;
	    break;

	case UNDO:		/* Reverse the SET action and free resources */
   	  tcp_row.dwState = oldbuf;
	    break;

	case COMMIT:		/* Confirm the SET, performing any irreversible actions,
					and free resources */    
    if((status = SetTcpEntry(&tcp_row)) != NO_ERROR){
            snmp_log(LOG_ERR,  "Error while trying to write connState %d, status = %d \n", 
                               tcp_row.dwState, status);
            return SNMP_ERR_COMMITFAILED;
    }    
	case FREE:		/* Free any resources allocated */    
	    break;
    }
    return SNMP_ERR_NOERROR;
} /* end of writeTcpEntry */
#endif /* WIN32 */