Merge pull request #5778 from ton31337/fix/add_doc_for_ebgp_connected_route_check

[mirror_frr.git] / lib / prefix.c

/*
 * Prefix related functions.
 * Copyright (C) 1997, 98, 99 Kunihiro Ishiguro
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra 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, or (at your option) any
 * later version.
 *
 * GNU Zebra 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; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <zebra.h>

#include "prefix.h"
#include "vty.h"
#include "sockunion.h"
#include "memory.h"
#include "log.h"
#include "jhash.h"
#include "lib_errors.h"
#include "printfrr.h"

DEFINE_MTYPE_STATIC(LIB, PREFIX, "Prefix")
DEFINE_MTYPE_STATIC(LIB, PREFIX_FLOWSPEC, "Prefix Flowspec")

/* Maskbit. */
static const uint8_t maskbit[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0,
                                  0xf8, 0xfc, 0xfe, 0xff};

/* Number of bits in prefix type. */
#ifndef PNBBY
#define PNBBY 8
#endif /* PNBBY */

#define MASKBIT(offset)  ((0xff << (PNBBY - (offset))) & 0xff)

int is_zero_mac(const struct ethaddr *mac)
{
        int i = 0;

        for (i = 0; i < ETH_ALEN; i++) {
                if (mac->octet[i])
                        return 0;
        }

        return 1;
}

unsigned int prefix_bit(const uint8_t *prefix, const uint16_t prefixlen)
{
        unsigned int offset = prefixlen / 8;
        unsigned int shift = 7 - (prefixlen % 8);

        return (prefix[offset] >> shift) & 1;
}

int str2family(const char *string)
{
        if (!strcmp("ipv4", string))
                return AF_INET;
        else if (!strcmp("ipv6", string))
                return AF_INET6;
        else if (!strcmp("ethernet", string))
                return AF_ETHERNET;
        else if (!strcmp("evpn", string))
                return AF_EVPN;
        return -1;
}

const char *family2str(int family)
{
        switch (family) {
        case AF_INET:
                return "IPv4";
        case AF_INET6:
                return "IPv6";
        case AF_ETHERNET:
                return "Ethernet";
        case AF_EVPN:
                return "Evpn";
        }
        return "?";
}

/* Address Famiy Identifier to Address Family converter. */
int afi2family(afi_t afi)
{
        if (afi == AFI_IP)
                return AF_INET;
        else if (afi == AFI_IP6)
                return AF_INET6;
        else if (afi == AFI_L2VPN)
                return AF_ETHERNET;
        /* NOTE: EVPN code should NOT use this interface. */
        return 0;
}

afi_t family2afi(int family)
{
        if (family == AF_INET)
                return AFI_IP;
        else if (family == AF_INET6)
                return AFI_IP6;
        else if (family == AF_ETHERNET || family == AF_EVPN)
                return AFI_L2VPN;
        return 0;
}

const char *afi2str(afi_t afi)
{
        switch (afi) {
        case AFI_IP:
                return "IPv4";
        case AFI_IP6:
                return "IPv6";
        case AFI_L2VPN:
                return "l2vpn";
        case AFI_MAX:
                return "bad-value";
        default:
                break;
        }
        return NULL;
}

const char *safi2str(safi_t safi)
{
        switch (safi) {
        case SAFI_UNICAST:
                return "unicast";
        case SAFI_MULTICAST:
                return "multicast";
        case SAFI_MPLS_VPN:
                return "vpn";
        case SAFI_ENCAP:
                return "encap";
        case SAFI_EVPN:
                return "evpn";
        case SAFI_LABELED_UNICAST:
                return "labeled-unicast";
        case SAFI_FLOWSPEC:
                return "flowspec";
        default:
                return "unknown";
        }
}

/* If n includes p prefix then return 1 else return 0. */
int prefix_match(const struct prefix *n, const struct prefix *p)
{
        int offset;
        int shift;
        const uint8_t *np, *pp;

        /* If n's prefix is longer than p's one return 0. */
        if (n->prefixlen > p->prefixlen)
                return 0;

        if (n->family == AF_FLOWSPEC) {
                /* prefixlen is unused. look at fs prefix len */
                if (n->u.prefix_flowspec.prefixlen >
                    p->u.prefix_flowspec.prefixlen)
                        return 0;

                /* Set both prefix's head pointer. */
                np = (const uint8_t *)&n->u.prefix_flowspec.ptr;
                pp = (const uint8_t *)&p->u.prefix_flowspec.ptr;

                offset = n->u.prefix_flowspec.prefixlen;

                while (offset--)
                        if (np[offset] != pp[offset])
                                return 0;
                return 1;
        }

        /* Set both prefix's head pointer. */
        np = n->u.val;
        pp = p->u.val;

        offset = n->prefixlen / PNBBY;
        shift = n->prefixlen % PNBBY;

        if (shift)
                if (maskbit[shift] & (np[offset] ^ pp[offset]))
                        return 0;

        while (offset--)
                if (np[offset] != pp[offset])
                        return 0;
        return 1;

}

/*
 * n is a type5 evpn prefix. This function tries to see if there is an
 * ip-prefix within n which matches prefix p
 * If n includes p prefix then return 1 else return 0.
 */
int evpn_type5_prefix_match(const struct prefix *n, const struct prefix *p)
{
        int offset;
        int shift;
        int prefixlen;
        const uint8_t *np, *pp;
        struct prefix_evpn *evp;

        if (n->family != AF_EVPN)
                return 0;

        evp = (struct prefix_evpn *)n;
        pp = p->u.val;

        if ((evp->prefix.route_type != 5) ||
            (p->family == AF_INET6 && !is_evpn_prefix_ipaddr_v6(evp)) ||
            (p->family == AF_INET && !is_evpn_prefix_ipaddr_v4(evp)) ||
            (is_evpn_prefix_ipaddr_none(evp)))
                return 0;

        prefixlen = evp->prefix.prefix_addr.ip_prefix_length;
        np = &evp->prefix.prefix_addr.ip.ip.addr;

        /* If n's prefix is longer than p's one return 0. */
        if (prefixlen > p->prefixlen)
                return 0;

        offset = prefixlen / PNBBY;
        shift = prefixlen % PNBBY;

        if (shift)
                if (maskbit[shift] & (np[offset] ^ pp[offset]))
                        return 0;

        while (offset--)
                if (np[offset] != pp[offset])
                        return 0;
        return 1;

}

/* If n includes p then return 1 else return 0. Prefix mask is not considered */
int prefix_match_network_statement(const struct prefix *n,
                                   const struct prefix *p)
{
        int offset;
        int shift;
        const uint8_t *np, *pp;

        /* Set both prefix's head pointer. */
        np = n->u.val;
        pp = p->u.val;

        offset = n->prefixlen / PNBBY;
        shift = n->prefixlen % PNBBY;

        if (shift)
                if (maskbit[shift] & (np[offset] ^ pp[offset]))
                        return 0;

        while (offset--)
                if (np[offset] != pp[offset])
                        return 0;
        return 1;
}

#ifdef __clang_analyzer__
#undef prefix_copy      /* cf. prefix.h */
#endif

void prefix_copy(union prefixptr udest, union prefixconstptr usrc)
{
        struct prefix *dest = udest.p;
        const struct prefix *src = usrc.p;

        dest->family = src->family;
        dest->prefixlen = src->prefixlen;

        if (src->family == AF_INET)
                dest->u.prefix4 = src->u.prefix4;
        else if (src->family == AF_INET6)
                dest->u.prefix6 = src->u.prefix6;
        else if (src->family == AF_ETHERNET) {
                memcpy(&dest->u.prefix_eth, &src->u.prefix_eth,
                       sizeof(struct ethaddr));
        } else if (src->family == AF_EVPN) {
                memcpy(&dest->u.prefix_evpn, &src->u.prefix_evpn,
                       sizeof(struct evpn_addr));
        } else if (src->family == AF_UNSPEC) {
                dest->u.lp.id = src->u.lp.id;
                dest->u.lp.adv_router = src->u.lp.adv_router;
        } else if (src->family == AF_FLOWSPEC) {
                void *temp;
                int len;

                len = src->u.prefix_flowspec.prefixlen;
                dest->u.prefix_flowspec.prefixlen =
                        src->u.prefix_flowspec.prefixlen;
                dest->family = src->family;
                temp = XCALLOC(MTYPE_PREFIX_FLOWSPEC, len);
                dest->u.prefix_flowspec.ptr = (uintptr_t)temp;
                memcpy((void *)dest->u.prefix_flowspec.ptr,
                       (void *)src->u.prefix_flowspec.ptr, len);
        } else {
                flog_err(EC_LIB_DEVELOPMENT,
                         "prefix_copy(): Unknown address family %d",
                         src->family);
                assert(0);
        }
}

/*
 * Return 1 if the address/netmask contained in the prefix structure
 * is the same, and else return 0.  For this routine, 'same' requires
 * that not only the prefix length and the network part be the same,
 * but also the host part.  Thus, 10.0.0.1/8 and 10.0.0.2/8 are not
 * the same.  Note that this routine has the same return value sense
 * as '==' (which is different from prefix_cmp).
 */
int prefix_same(union prefixconstptr up1, union prefixconstptr up2)
{
        const struct prefix *p1 = up1.p;
        const struct prefix *p2 = up2.p;

        if ((p1 && !p2) || (!p1 && p2))
                return 0;

        if (!p1 && !p2)
                return 1;

        if (p1->family == p2->family && p1->prefixlen == p2->prefixlen) {
                if (p1->family == AF_INET)
                        if (IPV4_ADDR_SAME(&p1->u.prefix4, &p2->u.prefix4))
                                return 1;
                if (p1->family == AF_INET6)
                        if (IPV6_ADDR_SAME(&p1->u.prefix6.s6_addr,
                                           &p2->u.prefix6.s6_addr))
                                return 1;
                if (p1->family == AF_ETHERNET)
                        if (!memcmp(&p1->u.prefix_eth, &p2->u.prefix_eth,
                                    sizeof(struct ethaddr)))
                                return 1;
                if (p1->family == AF_EVPN)
                        if (!memcmp(&p1->u.prefix_evpn, &p2->u.prefix_evpn,
                                    sizeof(struct evpn_addr)))
                                return 1;
                if (p1->family == AF_FLOWSPEC) {
                        if (p1->u.prefix_flowspec.prefixlen !=
                            p2->u.prefix_flowspec.prefixlen)
                                return 0;
                        if (!memcmp(&p1->u.prefix_flowspec.ptr,
                                    &p2->u.prefix_flowspec.ptr,
                                    p2->u.prefix_flowspec.prefixlen))
                                return 1;
                }
        }
        return 0;
}

/*
 * Return -1/0/1 comparing the prefixes in a way that gives a full/linear
 * order.
 *
 * Network prefixes are considered the same if the prefix lengths are equal
 * and the network parts are the same.  Host bits (which are considered masked
 * by the prefix length) are not significant.  Thus, 10.0.0.1/8 and
 * 10.0.0.2/8 are considered equivalent by this routine.  Note that
 * this routine has the same return sense as strcmp (which is different
 * from prefix_same).
 */
int prefix_cmp(union prefixconstptr up1, union prefixconstptr up2)
{
        const struct prefix *p1 = up1.p;
        const struct prefix *p2 = up2.p;
        int offset;
        int shift;
        int i;

        /* Set both prefix's head pointer. */
        const uint8_t *pp1;
        const uint8_t *pp2;

        if (p1->family != p2->family)
                return numcmp(p1->family, p2->family);
        if (p1->family == AF_FLOWSPEC) {
                pp1 = (const uint8_t *)p1->u.prefix_flowspec.ptr;
                pp2 = (const uint8_t *)p2->u.prefix_flowspec.ptr;

                if (p1->u.prefix_flowspec.prefixlen !=
                    p2->u.prefix_flowspec.prefixlen)
                        return numcmp(p1->u.prefix_flowspec.prefixlen,
                                      p2->u.prefix_flowspec.prefixlen);

                offset = p1->u.prefix_flowspec.prefixlen;
                while (offset--)
                        if (pp1[offset] != pp2[offset])
                                return numcmp(pp1[offset], pp2[offset]);
                return 0;
        }
        pp1 = p1->u.val;
        pp2 = p2->u.val;

        if (p1->prefixlen != p2->prefixlen)
                return numcmp(p1->prefixlen, p2->prefixlen);
        offset = p1->prefixlen / PNBBY;
        shift = p1->prefixlen % PNBBY;

        i = memcmp(pp1, pp2, offset);
        if (i)
                return i;

        /*
         * At this point offset was the same, if we have shift
         * that means we still have data to compare, if shift is
         * 0 then we are at the end of the data structure
         * and should just return, as that we will be accessing
         * memory beyond the end of the party zone
         */
        if (shift)
                return numcmp(pp1[offset] & maskbit[shift],
                              pp2[offset] & maskbit[shift]);

        return 0;
}

/*
 * Count the number of common bits in 2 prefixes. The prefix length is
 * ignored for this function; the whole prefix is compared. If the prefix
 * address families don't match, return -1; otherwise the return value is
 * in range 0 ... maximum prefix length for the address family.
 */
int prefix_common_bits(const struct prefix *p1, const struct prefix *p2)
{
        int pos, bit;
        int length = 0;
        uint8_t xor ;

        /* Set both prefix's head pointer. */
        const uint8_t *pp1 = p1->u.val;
        const uint8_t *pp2 = p2->u.val;

        if (p1->family == AF_INET)
                length = IPV4_MAX_BYTELEN;
        if (p1->family == AF_INET6)
                length = IPV6_MAX_BYTELEN;
        if (p1->family == AF_ETHERNET)
                length = ETH_ALEN;
        if (p1->family == AF_EVPN)
                length = 8 * sizeof(struct evpn_addr);

        if (p1->family != p2->family || !length)
                return -1;

        for (pos = 0; pos < length; pos++)
                if (pp1[pos] != pp2[pos])
                        break;
        if (pos == length)
                return pos * 8;

        xor = pp1[pos] ^ pp2[pos];
        for (bit = 0; bit < 8; bit++)
                if (xor&(1 << (7 - bit)))
                        break;

        return pos * 8 + bit;
}

/* Return prefix family type string. */
const char *prefix_family_str(const struct prefix *p)
{
        if (p->family == AF_INET)
                return "inet";
        if (p->family == AF_INET6)
                return "inet6";
        if (p->family == AF_ETHERNET)
                return "ether";
        if (p->family == AF_EVPN)
                return "evpn";
        return "unspec";
}

/* Allocate new prefix_ipv4 structure. */
struct prefix_ipv4 *prefix_ipv4_new(void)
{
        struct prefix_ipv4 *p;

        /* Call prefix_new to allocate a full-size struct prefix to avoid
           problems
           where the struct prefix_ipv4 is cast to struct prefix and unallocated
           bytes were being referenced (e.g. in structure assignments). */
        p = (struct prefix_ipv4 *)prefix_new();
        p->family = AF_INET;
        return p;
}

/* Free prefix_ipv4 structure. */
void prefix_ipv4_free(struct prefix_ipv4 **p)
{
        prefix_free((struct prefix **)p);
}

/* If given string is valid return 1 else return 0 */
int str2prefix_ipv4(const char *str, struct prefix_ipv4 *p)
{
        int ret;
        int plen;
        char *pnt;
        char *cp;

        /* Find slash inside string. */
        pnt = strchr(str, '/');

        /* String doesn't contail slash. */
        if (pnt == NULL) {
                /* Convert string to prefix. */
                ret = inet_pton(AF_INET, str, &p->prefix);
                if (ret == 0)
                        return 0;

                /* If address doesn't contain slash we assume it host address.
                 */
                p->family = AF_INET;
                p->prefixlen = IPV4_MAX_BITLEN;

                return ret;
        } else {
                cp = XMALLOC(MTYPE_TMP, (pnt - str) + 1);
                memcpy(cp, str, pnt - str);
                *(cp + (pnt - str)) = '\0';
                ret = inet_pton(AF_INET, cp, &p->prefix);
                XFREE(MTYPE_TMP, cp);
                if (ret == 0)
                        return 0;

                /* Get prefix length. */
                plen = (uint8_t)atoi(++pnt);
                if (plen > IPV4_MAX_PREFIXLEN)
                        return 0;

                p->family = AF_INET;
                p->prefixlen = plen;
        }

        return ret;
}

/* When string format is invalid return 0. */
int str2prefix_eth(const char *str, struct prefix_eth *p)
{
        int ret = 0;
        int plen = 48;
        char *pnt;
        char *cp = NULL;
        const char *str_addr = str;
        unsigned int a[6];
        int i;
        bool slash = false;

        if (!strcmp(str, "any")) {
                memset(p, 0, sizeof(*p));
                p->family = AF_ETHERNET;
                return 1;
        }

        /* Find slash inside string. */
        pnt = strchr(str, '/');

        if (pnt) {
                /* Get prefix length. */
                plen = (uint8_t)atoi(++pnt);
                if (plen > 48) {
                        ret = 0;
                        goto done;
                }

                cp = XMALLOC(MTYPE_TMP, (pnt - str) + 1);
                memcpy(cp, str, pnt - str);
                *(cp + (pnt - str)) = '\0';

                str_addr = cp;
                slash = true;
        }

        /* Convert string to prefix. */
        if (sscanf(str_addr, "%2x:%2x:%2x:%2x:%2x:%2x", a + 0, a + 1, a + 2,
                   a + 3, a + 4, a + 5)
            != 6) {
                ret = 0;
                goto done;
        }
        for (i = 0; i < 6; ++i) {
                p->eth_addr.octet[i] = a[i] & 0xff;
        }
        p->prefixlen = plen;
        p->family = AF_ETHERNET;

        /*
         * special case to allow old configurations to work
         * Since all zero's is implicitly meant to allow
         * a comparison to zero, let's assume
         */
        if (!slash && is_zero_mac(&(p->eth_addr)))
                p->prefixlen = 0;

        ret = 1;

done:
        XFREE(MTYPE_TMP, cp);

        return ret;
}

/* Convert masklen into IP address's netmask (network byte order). */
void masklen2ip(const int masklen, struct in_addr *netmask)
{
        assert(masklen >= 0 && masklen <= IPV4_MAX_BITLEN);

        /* left shift is only defined for less than the size of the type.
         * we unconditionally use long long in case the target platform
         * has defined behaviour for << 32 (or has a 64-bit left shift) */

        if (sizeof(unsigned long long) > 4)
                netmask->s_addr = htonl(0xffffffffULL << (32 - masklen));
        else
                netmask->s_addr =
                        htonl(masklen ? 0xffffffffU << (32 - masklen) : 0);
}

/* Convert IP address's netmask into integer. We assume netmask is
 * sequential one. Argument netmask should be network byte order. */
uint8_t ip_masklen(struct in_addr netmask)
{
        uint32_t tmp = ~ntohl(netmask.s_addr);

        /*
         * clz: count leading zeroes. sadly, the behaviour of this builtin is
         * undefined for a 0 argument, even though most CPUs give 32
         */
        return tmp ? __builtin_clz(tmp) : 32;
}

/* Apply mask to IPv4 prefix (network byte order). */
void apply_mask_ipv4(struct prefix_ipv4 *p)
{
        struct in_addr mask;
        masklen2ip(p->prefixlen, &mask);
        p->prefix.s_addr &= mask.s_addr;
}

/* If prefix is 0.0.0.0/0 then return 1 else return 0. */
int prefix_ipv4_any(const struct prefix_ipv4 *p)
{
        return (p->prefix.s_addr == INADDR_ANY && p->prefixlen == 0);
}

/* Allocate a new ip version 6 route */
struct prefix_ipv6 *prefix_ipv6_new(void)
{
        struct prefix_ipv6 *p;

        /* Allocate a full-size struct prefix to avoid problems with structure
           size mismatches. */
        p = (struct prefix_ipv6 *)prefix_new();
        p->family = AF_INET6;
        return p;
}

/* Free prefix for IPv6. */
void prefix_ipv6_free(struct prefix_ipv6 **p)
{
        prefix_free((struct prefix **)p);
}

/* If given string is valid return 1 else return 0 */
int str2prefix_ipv6(const char *str, struct prefix_ipv6 *p)
{
        char *pnt;
        char *cp;
        int ret;

        pnt = strchr(str, '/');

        /* If string doesn't contain `/' treat it as host route. */
        if (pnt == NULL) {
                ret = inet_pton(AF_INET6, str, &p->prefix);
                if (ret == 0)
                        return 0;
                p->prefixlen = IPV6_MAX_BITLEN;
        } else {
                int plen;

                cp = XMALLOC(MTYPE_TMP, (pnt - str) + 1);
                memcpy(cp, str, pnt - str);
                *(cp + (pnt - str)) = '\0';
                ret = inet_pton(AF_INET6, cp, &p->prefix);
                XFREE(MTYPE_TMP, cp);
                if (ret == 0)
                        return 0;
                plen = (uint8_t)atoi(++pnt);
                if (plen > IPV6_MAX_BITLEN)
                        return 0;
                p->prefixlen = plen;
        }
        p->family = AF_INET6;

        return ret;
}

/* Convert struct in6_addr netmask into integer.
 * FIXME return uint8_t as ip_maskleni() does. */
int ip6_masklen(struct in6_addr netmask)
{
        if (netmask.s6_addr32[0] != 0xffffffffU)
                return __builtin_clz(~ntohl(netmask.s6_addr32[0]));
        if (netmask.s6_addr32[1] != 0xffffffffU)
                return __builtin_clz(~ntohl(netmask.s6_addr32[1])) + 32;
        if (netmask.s6_addr32[2] != 0xffffffffU)
                return __builtin_clz(~ntohl(netmask.s6_addr32[2])) + 64;
        if (netmask.s6_addr32[3] != 0xffffffffU)
                return __builtin_clz(~ntohl(netmask.s6_addr32[3])) + 96;
        /* note __builtin_clz(0) is undefined */
        return 128;
}

void masklen2ip6(const int masklen, struct in6_addr *netmask)
{
        assert(masklen >= 0 && masklen <= IPV6_MAX_BITLEN);

        if (masklen == 0) {
                /* note << 32 is undefined */
                memset(netmask, 0, sizeof(*netmask));
        } else if (masklen <= 32) {
                netmask->s6_addr32[0] = htonl(0xffffffffU << (32 - masklen));
                netmask->s6_addr32[1] = 0;
                netmask->s6_addr32[2] = 0;
                netmask->s6_addr32[3] = 0;
        } else if (masklen <= 64) {
                netmask->s6_addr32[0] = 0xffffffffU;
                netmask->s6_addr32[1] = htonl(0xffffffffU << (64 - masklen));
                netmask->s6_addr32[2] = 0;
                netmask->s6_addr32[3] = 0;
        } else if (masklen <= 96) {
                netmask->s6_addr32[0] = 0xffffffffU;
                netmask->s6_addr32[1] = 0xffffffffU;
                netmask->s6_addr32[2] = htonl(0xffffffffU << (96 - masklen));
                netmask->s6_addr32[3] = 0;
        } else {
                netmask->s6_addr32[0] = 0xffffffffU;
                netmask->s6_addr32[1] = 0xffffffffU;
                netmask->s6_addr32[2] = 0xffffffffU;
                netmask->s6_addr32[3] = htonl(0xffffffffU << (128 - masklen));
        }
}

void apply_mask_ipv6(struct prefix_ipv6 *p)
{
        uint8_t *pnt;
        int index;
        int offset;

        index = p->prefixlen / 8;

        if (index < 16) {
                pnt = (uint8_t *)&p->prefix;
                offset = p->prefixlen % 8;

                pnt[index] &= maskbit[offset];
                index++;

                while (index < 16)
                        pnt[index++] = 0;
        }
}

void apply_mask(struct prefix *p)
{
        switch (p->family) {
        case AF_INET:
                apply_mask_ipv4((struct prefix_ipv4 *)p);
                break;
        case AF_INET6:
                apply_mask_ipv6((struct prefix_ipv6 *)p);
                break;
        default:
                break;
        }
        return;
}

/* Utility function of convert between struct prefix <=> union sockunion. */
struct prefix *sockunion2hostprefix(const union sockunion *su,
                                    struct prefix *prefix)
{
        if (su->sa.sa_family == AF_INET) {
                struct prefix_ipv4 *p;

                p = prefix ? (struct prefix_ipv4 *)prefix : prefix_ipv4_new();
                p->family = AF_INET;
                p->prefix = su->sin.sin_addr;
                p->prefixlen = IPV4_MAX_BITLEN;
                return (struct prefix *)p;
        }
        if (su->sa.sa_family == AF_INET6) {
                struct prefix_ipv6 *p;

                p = prefix ? (struct prefix_ipv6 *)prefix : prefix_ipv6_new();
                p->family = AF_INET6;
                p->prefixlen = IPV6_MAX_BITLEN;
                memcpy(&p->prefix, &su->sin6.sin6_addr,
                       sizeof(struct in6_addr));
                return (struct prefix *)p;
        }
        return NULL;
}

void prefix2sockunion(const struct prefix *p, union sockunion *su)
{
        memset(su, 0, sizeof(*su));

        su->sa.sa_family = p->family;
        if (p->family == AF_INET)
                su->sin.sin_addr = p->u.prefix4;
        if (p->family == AF_INET6)
                memcpy(&su->sin6.sin6_addr, &p->u.prefix6,
                       sizeof(struct in6_addr));
}

int prefix_blen(const struct prefix *p)
{
        switch (p->family) {
        case AF_INET:
                return IPV4_MAX_BYTELEN;
                break;
        case AF_INET6:
                return IPV6_MAX_BYTELEN;
                break;
        case AF_ETHERNET:
                return ETH_ALEN;
                break;
        }
        return 0;
}

/* Generic function for conversion string to struct prefix. */
int str2prefix(const char *str, struct prefix *p)
{
        int ret;

        if (!str || !p)
                return 0;

        /* First we try to convert string to struct prefix_ipv4. */
        ret = str2prefix_ipv4(str, (struct prefix_ipv4 *)p);
        if (ret)
                return ret;

        /* Next we try to convert string to struct prefix_ipv6. */
        ret = str2prefix_ipv6(str, (struct prefix_ipv6 *)p);
        if (ret)
                return ret;

        /* Next we try to convert string to struct prefix_eth. */
        ret = str2prefix_eth(str, (struct prefix_eth *)p);
        if (ret)
                return ret;

        return 0;
}

static const char *prefixevpn_ead2str(const struct prefix_evpn *p, char *str,
                                      int size)
{
        snprintf(str, size, "Unsupported EVPN prefix");
        return str;
}

static const char *prefixevpn_macip2str(const struct prefix_evpn *p, char *str,
                                        int size)
{
        uint8_t family;
        char buf[PREFIX2STR_BUFFER];
        char buf2[ETHER_ADDR_STRLEN];

        if (is_evpn_prefix_ipaddr_none(p))
                snprintf(str, size, "[%d]:[%s]/%d",
                         p->prefix.route_type,
                         prefix_mac2str(&p->prefix.macip_addr.mac,
                                        buf2, sizeof(buf2)),
                         p->prefixlen);
        else {
                family = is_evpn_prefix_ipaddr_v4(p)
                                 ? AF_INET
                                 : AF_INET6;
                snprintf(str, size, "[%d]:[%s]:[%s]/%d",
                         p->prefix.route_type,
                         prefix_mac2str(&p->prefix.macip_addr.mac,
                                        buf2, sizeof(buf2)),
                         inet_ntop(family,
                                   &p->prefix.macip_addr.ip.ip.addr,
                                   buf, PREFIX2STR_BUFFER),
                         p->prefixlen);
        }
        return str;
}

static const char *prefixevpn_imet2str(const struct prefix_evpn *p, char *str,
                                       int size)
{
        uint8_t family;
        char buf[PREFIX2STR_BUFFER];

        family = is_evpn_prefix_ipaddr_v4(p)
                         ? AF_INET
                         : AF_INET6;
        snprintf(str, size, "[%d]:[%s]/%d", p->prefix.route_type,
                 inet_ntop(family,
                           &p->prefix.imet_addr.ip.ip.addr, buf,
                           PREFIX2STR_BUFFER),
                 p->prefixlen);
        return str;
}

static const char *prefixevpn_es2str(const struct prefix_evpn *p, char *str,
                                     int size)
{
        char buf[ESI_STR_LEN];

        snprintf(str, size, "[%d]:[%s]:[%s]/%d", p->prefix.route_type,
                 esi_to_str(&p->prefix.es_addr.esi, buf, sizeof(buf)),
                 inet_ntoa(p->prefix.es_addr.ip.ipaddr_v4),
                 p->prefixlen);
        return str;
}

static const char *prefixevpn_prefix2str(const struct prefix_evpn *p, char *str,
                                         int size)
{
        uint8_t family;
        char buf[PREFIX2STR_BUFFER];

        family = is_evpn_prefix_ipaddr_v4(p)
                         ? AF_INET
                         : AF_INET6;
        snprintf(str, size, "[%d]:[%u][%s/%d]/%d",
                 p->prefix.route_type,
                 p->prefix.prefix_addr.eth_tag,
                 inet_ntop(family,
                           &p->prefix.prefix_addr.ip.ip.addr, buf,
                           PREFIX2STR_BUFFER),
                 p->prefix.prefix_addr.ip_prefix_length,
                 p->prefixlen);
        return str;
}

static const char *prefixevpn2str(const struct prefix_evpn *p, char *str,
                                  int size)
{
        switch (p->prefix.route_type) {
        case 1:
                return prefixevpn_ead2str(p, str, size);
        case 2:
                return prefixevpn_macip2str(p, str, size);
        case 3:
                return prefixevpn_imet2str(p, str, size);
        case 4:
                return prefixevpn_es2str(p, str, size);
        case 5:
                return prefixevpn_prefix2str(p, str, size);
        default:
                snprintf(str, size, "Unsupported EVPN prefix");
                break;
        }
        return str;
}

const char *prefix2str(union prefixconstptr pu, char *str, int size)
{
        const struct prefix *p = pu.p;
        char buf[PREFIX2STR_BUFFER];
        int byte, tmp, a, b;
        bool z = false;
        size_t l;

        switch (p->family) {
        case AF_INET:
        case AF_INET6:
                inet_ntop(p->family, &p->u.prefix, buf, sizeof(buf));
                l = strlen(buf);
                buf[l++] = '/';
                byte = p->prefixlen;
                if ((tmp = p->prefixlen - 100) >= 0) {
                        buf[l++] = '1';
                        z = true;
                        byte = tmp;
                }
                b = byte % 10;
                a = byte / 10;
                if (a || z)
                        buf[l++] = '0' + a;
                buf[l++] = '0' + b;
                buf[l] = '\0';
                strlcpy(str, buf, size);
                break;

        case AF_ETHERNET:
                snprintf(str, size, "%s/%d",
                         prefix_mac2str(&p->u.prefix_eth, buf, sizeof(buf)),
                         p->prefixlen);
                break;

        case AF_EVPN:
                prefixevpn2str((const struct prefix_evpn *)p, str, size);
                break;

        case AF_FLOWSPEC:
                strlcpy(str, "FS prefix", size);
                break;

        default:
                strlcpy(str, "UNK prefix", size);
                break;
        }

        return str;
}

void prefix_mcast_inet4_dump(const char *onfail, struct in_addr addr,
                char *buf, int buf_size)
{
        int save_errno = errno;

        if (addr.s_addr == INADDR_ANY)
                strlcpy(buf, "*", buf_size);
        else {
                if (!inet_ntop(AF_INET, &addr, buf, buf_size)) {
                        if (onfail)
                                snprintf(buf, buf_size, "%s", onfail);
                }
        }

        errno = save_errno;
}

const char *prefix_sg2str(const struct prefix_sg *sg, char *sg_str)
{
        char src_str[INET_ADDRSTRLEN];
        char grp_str[INET_ADDRSTRLEN];

        prefix_mcast_inet4_dump("<src?>", sg->src, src_str, sizeof(src_str));
        prefix_mcast_inet4_dump("<grp?>", sg->grp, grp_str, sizeof(grp_str));
        snprintf(sg_str, PREFIX_SG_STR_LEN, "(%s,%s)", src_str, grp_str);

        return sg_str;
}

struct prefix *prefix_new(void)
{
        struct prefix *p;

        p = XCALLOC(MTYPE_PREFIX, sizeof *p);
        return p;
}

void prefix_free_lists(void *arg)
{
        struct prefix *p = arg;

        prefix_free(&p);
}

/* Free prefix structure. */
void prefix_free(struct prefix **p)
{
        XFREE(MTYPE_PREFIX, *p);
}

/* Utility function to convert ipv4 prefixes to Classful prefixes */
void apply_classful_mask_ipv4(struct prefix_ipv4 *p)
{

        uint32_t destination;

        destination = ntohl(p->prefix.s_addr);

        if (p->prefixlen == IPV4_MAX_PREFIXLEN)
                ;
        /* do nothing for host routes */
        else if (IN_CLASSC(destination)) {
                p->prefixlen = 24;
                apply_mask_ipv4(p);
        } else if (IN_CLASSB(destination)) {
                p->prefixlen = 16;
                apply_mask_ipv4(p);
        } else {
                p->prefixlen = 8;
                apply_mask_ipv4(p);
        }
}

in_addr_t ipv4_broadcast_addr(in_addr_t hostaddr, int masklen)
{
        struct in_addr mask;

        masklen2ip(masklen, &mask);
        return (masklen != IPV4_MAX_PREFIXLEN - 1) ?
                /* normal case */
                (hostaddr | ~mask.s_addr)
                   :
                /* For prefix 31 return 255.255.255.255 (RFC3021) */
                htonl(0xFFFFFFFF);
}

/* Utility function to convert ipv4 netmask to prefixes
   ex.) "1.1.0.0" "255.255.0.0" => "1.1.0.0/16"
   ex.) "1.0.0.0" NULL => "1.0.0.0/8"                   */
int netmask_str2prefix_str(const char *net_str, const char *mask_str,
                           char *prefix_str)
{
        struct in_addr network;
        struct in_addr mask;
        uint8_t prefixlen;
        uint32_t destination;
        int ret;

        ret = inet_aton(net_str, &network);
        if (!ret)
                return 0;

        if (mask_str) {
                ret = inet_aton(mask_str, &mask);
                if (!ret)
                        return 0;

                prefixlen = ip_masklen(mask);
        } else {
                destination = ntohl(network.s_addr);

                if (network.s_addr == INADDR_ANY)
                        prefixlen = 0;
                else if (IN_CLASSC(destination))
                        prefixlen = 24;
                else if (IN_CLASSB(destination))
                        prefixlen = 16;
                else if (IN_CLASSA(destination))
                        prefixlen = 8;
                else
                        return 0;
        }

        sprintf(prefix_str, "%s/%d", net_str, prefixlen);

        return 1;
}

/* Utility function for making IPv6 address string. */
const char *inet6_ntoa(struct in6_addr addr)
{
        static char buf[INET6_ADDRSTRLEN];

        inet_ntop(AF_INET6, &addr, buf, INET6_ADDRSTRLEN);
        return buf;
}

/* converts to internal representation of mac address
 * returns 1 on success, 0 otherwise
 * format accepted: AA:BB:CC:DD:EE:FF
 * if mac parameter is null, then check only
 */
int prefix_str2mac(const char *str, struct ethaddr *mac)
{
        unsigned int a[6];
        int i;

        if (!str)
                return 0;

        if (sscanf(str, "%2x:%2x:%2x:%2x:%2x:%2x", a + 0, a + 1, a + 2, a + 3,
                   a + 4, a + 5)
            != 6) {
                /* error in incoming str length */
                return 0;
        }
        /* valid mac address */
        if (!mac)
                return 1;
        for (i = 0; i < 6; ++i)
                mac->octet[i] = a[i] & 0xff;
        return 1;
}

char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size)
{
        char *ptr;

        if (!mac)
                return NULL;
        if (!buf)
                ptr = XMALLOC(MTYPE_TMP, ETHER_ADDR_STRLEN * sizeof(char));
        else {
                assert(size >= ETHER_ADDR_STRLEN);
                ptr = buf;
        }
        snprintf(ptr, (ETHER_ADDR_STRLEN), "%02x:%02x:%02x:%02x:%02x:%02x",
                 (uint8_t)mac->octet[0], (uint8_t)mac->octet[1],
                 (uint8_t)mac->octet[2], (uint8_t)mac->octet[3],
                 (uint8_t)mac->octet[4], (uint8_t)mac->octet[5]);
        return ptr;
}

unsigned prefix_hash_key(const void *pp)
{
        struct prefix copy;

        if (((struct prefix *)pp)->family == AF_FLOWSPEC) {
                uint32_t len;
                void *temp;

                /* make sure *all* unused bits are zero,
                 * particularly including alignment /
                 * padding and unused prefix bytes.
                 */
                memset(&copy, 0, sizeof(copy));
                prefix_copy(&copy, (struct prefix *)pp);
                len = jhash((void *)copy.u.prefix_flowspec.ptr,
                            copy.u.prefix_flowspec.prefixlen,
                            0x55aa5a5a);
                temp = (void *)copy.u.prefix_flowspec.ptr;
                XFREE(MTYPE_PREFIX_FLOWSPEC, temp);
                copy.u.prefix_flowspec.ptr = (uintptr_t)NULL;
                return len;
        }
        /* make sure *all* unused bits are zero, particularly including
         * alignment /
         * padding and unused prefix bytes. */
        memset(&copy, 0, sizeof(copy));
        prefix_copy(&copy, (struct prefix *)pp);
        return jhash(&copy,
                     offsetof(struct prefix, u.prefix) + PSIZE(copy.prefixlen),
                     0x55aa5a5a);
}

/* converts to internal representation of esi
 * returns 1 on success, 0 otherwise
 * format accepted: aa:aa:aa:aa:aa:aa:aa:aa:aa:aa
 * if esi parameter is null, then check only
 */
int str_to_esi(const char *str, esi_t *esi)
{
        int i;
        unsigned int a[ESI_BYTES];

        if (!str)
                return 0;

        if (sscanf(str, "%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x",
                   a + 0, a + 1, a + 2, a + 3,
                   a + 4, a + 5, a + 6, a + 7,
                   a + 8, a + 9)
            != ESI_BYTES) {
                /* error in incoming str length */
                return 0;
        }

        /* valid ESI */
        if (!esi)
                return 1;
        for (i = 0; i < ESI_BYTES; ++i)
                esi->val[i] = a[i] & 0xff;
        return 1;
}

char *esi_to_str(const esi_t *esi, char *buf, int size)
{
        char *ptr;

        if (!esi)
                return NULL;
        if (!buf)
                ptr = XMALLOC(MTYPE_TMP, ESI_STR_LEN * sizeof(char));
        else {
                assert(size >= ESI_STR_LEN);
                ptr = buf;
        }

        snprintf(ptr, ESI_STR_LEN,
                 "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
                 esi->val[0], esi->val[1], esi->val[2],
                 esi->val[3], esi->val[4], esi->val[5],
                 esi->val[6], esi->val[7], esi->val[8],
                 esi->val[9]);
        return ptr;
}

printfrr_ext_autoreg_p("I4", printfrr_i4)
static ssize_t printfrr_i4(char *buf, size_t bsz, const char *fmt,
                           int prec, const void *ptr)
{
        inet_ntop(AF_INET, ptr, buf, bsz);
        return 2;
}

printfrr_ext_autoreg_p("I6", printfrr_i6)
static ssize_t printfrr_i6(char *buf, size_t bsz, const char *fmt,
                           int prec, const void *ptr)
{
        inet_ntop(AF_INET6, ptr, buf, bsz);
        return 2;
}

printfrr_ext_autoreg_p("FX", printfrr_pfx)
static ssize_t printfrr_pfx(char *buf, size_t bsz, const char *fmt,
                            int prec, const void *ptr)
{
        prefix2str(ptr, buf, bsz);
        return 2;
}

printfrr_ext_autoreg_p("SG4", printfrr_psg)
static ssize_t printfrr_psg(char *buf, size_t bsz, const char *fmt,
                            int prec, const void *ptr)
{
        const struct prefix_sg *sg = ptr;
        struct fbuf fb = { .buf = buf, .pos = buf, .len = bsz - 1 };

        if (sg->src.s_addr == INADDR_ANY)
                bprintfrr(&fb, "(*,");
        else
                bprintfrr(&fb, "(%pI4,", &sg->src);

        if (sg->grp.s_addr == INADDR_ANY)
                bprintfrr(&fb, "*)");
        else
                bprintfrr(&fb, "%pI4)", &sg->grp);

        fb.pos[0] = '\0';
        return 3;
}