cidr_get.c

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/*
 * cidr_get - Get and return various semi-raw bits of info
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <errno.h>
#include <stdlib.h>
#include <string.h>

#include "cidr.h"
#include "abstract_mem.h"



/* Get the prefix length */
int
cidr_get_pflen(const CIDR *block)
{
        int i, j;
        int foundnmh;
        int pflen;

        if(block==NULL)
        {
                errno = EFAULT;
                return(-1);
        }

        /* Where do we start? */
        if(block->proto==CIDR_IPV4)
                i=12;
        else if(block->proto==CIDR_IPV6)
                i=0;
        else
        {
                errno = ENOENT; /* Bad errno */
                return(-1); /* Unknown */
        }
        
        /*
         * We're intentionally not supporting non-contiguous netmasks.  So,
         * if we find one, bomb out.
         */
        foundnmh=0;
        pflen=0;
        for(/* i */ ; i<=15 ; i++)
        {
                for(j=7 ; j>=0 ; j--)
                {
                        if((block->mask)[i] & (1<<j))
                        {
                                /*
                                 * This is a network bit (1).  If we've already seen a
                                 * host bit (0), we need to bomb.
                                 */
                                if(foundnmh==1)
                                {
                                        errno = EINVAL;
                                        return(-1);
                                }

                                pflen++;
                        }
                        else
                                foundnmh=1; /* A host bit */
                }
        }
        
        /* If we get here, return the length */
        return(pflen);
}


/* Get the address bits */
uint8_t *
cidr_get_addr(const CIDR *addr)
{
        uint8_t *toret;

        if(addr==NULL)
        {
                errno = EFAULT;
                return(NULL);
        }

        toret = gsh_calloc(16, sizeof(uint8_t));
        if(toret==NULL)
        {
                errno = ENOMEM;
                return(NULL);
        }

        /* Copy 'em in */
        memcpy(toret, addr->addr, sizeof(addr->addr));

        return(toret);
}


/* Get the netmask bits */
uint8_t *
cidr_get_mask(const CIDR *addr)
{
        uint8_t *toret;

        if(addr==NULL)
        {
                errno = EFAULT;
                return(NULL);
        }

        toret = gsh_calloc(16, sizeof(uint8_t));
        if(toret==NULL)
        {
                errno = ENOMEM;
                return(NULL);
        }

        /* Copy 'em in */
        memcpy(toret, addr->mask, sizeof(addr->mask));

        return(toret);
}


/* Get the protocol */
int
cidr_get_proto(const CIDR *addr)
{

        if(addr==NULL)
        {
                errno = EFAULT;
                return(-1);
        }

        return(addr->proto);
}