abinary.c

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/*
 *   This program 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 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/** Routines to encode / decode Ascend's filter attributes
 *
 * @file src/protocols/radius/abinary.c
 *
 * @copyright 2003,2006 The FreeRADIUS server project
 */
RCSID("$Id: 8e951a2aade5c236b163533aa837beeed4c30a17 $")
 
#include <freeradius-devel/util/base16.h>
#include <freeradius-devel/util/misc.h>
#include <freeradius-devel/util/pair.h>
 
#include "radius.h"
 
/*
 * Two types of filters are supported, GENERIC and IP.  The identifiers
 * are:
 */
 
typedef enum : uint8_t {
        ASCEND_FILTER_GENERIC = 0,
        ASCEND_FILTER_IP = 1,
        ASCEND_FILTER_IPX = 2,
        ASCEND_FILTER_IPV6 = 3
} ascend_filter_type_t;
 
/*
 * Generic filters mask and match up to RAD_MAX_FILTER_LEN bytes
 * starting at some offset.  The length is:
 */
#define RAD_MAX_FILTER_LEN      6
 
/*
 * ASCEND extensions for ABINARY filters
 */
 
#define IPX_NODE_ADDR_LEN               6
 
/*
 *      ascend_ip_filter_t
 *
 *      The binary format of an IP filter.  ALL fields are stored in
 *      network byte order.
 *
 *      srcip:          The source IP address.
 *
 *      dstip:          The destination IP address.
 *
 *      srcmask:        The number of leading one bits in the source address
 *                      mask.  Specifies the bits of interest.
 *
 *      dstmask:        The number of leading one bits in the destination
 *                      address mask. Specifies the bits of interest.
 *
 *      proto:          The IP protocol number
 *
 *      established:    A boolean value.  true when we care about the
 *                      established state of a TCP connection.  false when
 *                      we dont care.
 *
 *      srcport:        TCP or UDP source port number.
 *
 *      dstport:        TCP or UDP destination port number.
 *
 *      srcPortCmp:     One of the values of the RadFilterComparison
 *                      enumeration, specifying how to compare the
 *                      srcport value.
 *
 *      dstPortCmp:     One of the values of the RadFilterComparison
 *                      enumeration, specifying how to compare the
 *                      dstport value.
 *
 *      fill:           Round things out to a int16_t boundary.
 */
typedef struct {
        uint32_t        srcip;
        uint32_t        dstip;
        uint8_t         srcmask;
        uint8_t         dstmask;
        uint8_t         proto;
        uint8_t         established;
        uint16_t        srcport;
        uint16_t        dstport;
        uint8_t         srcPortComp;
        uint8_t         dstPortComp;
 
        // @todo - extra juniper stuff
} ascend_ip_filter_t;
 
 
/*
 *      ascend_ip_filter_t
 *
 *      The binary format of an IP filter.  ALL fields are stored in
 *      network byte order.
 *
 *      srcip:          The source IP address.
 *
 *      dstip:          The destination IP address.
 *
 *      srcmask:        The number of leading one bits in the source address
 *                      mask.  Specifies the bits of interest.
 *
 *      dstmask:        The number of leading one bits in the destination
 *                      address mask. Specifies the bits of interest.
 *
 *      proto:          The IP protocol number
 *
 *      established:    A boolean value.  true when we care about the
 *                      established state of a TCP connection.  false when
 *                      we dont care.
 *
 *      srcport:        TCP or UDP source port number.
 *
 *      dstport:        TCP or UDP destination port number.
 *
 *      srcPortCmp:     One of the values of the RadFilterComparison
 *                      enumeration, specifying how to compare the
 *                      srcport value.
 *
 *      dstPortCmp:     One of the values of the RadFilterComparison
 *                      enumeration, specifying how to compare the
 *                      dstport value.
 *
 *      fill:           Round things out to a int16_t boundary.
 */
typedef struct {
        uint8_t         srcip[16];
        uint8_t         dstip[16];
        uint8_t         srcmask;
        uint8_t         dstmask;
        uint8_t         proto;
        uint8_t         established;
        uint16_t        srcport;
        uint16_t        dstport;
        uint8_t         srcPortComp;
        uint8_t         dstPortComp;
 
        // @todo - extra juniper stuff
} ascend_ipv6_filter_t;
 
 
/*
 *      ascend_ipx_net_t
 *
 *      net:      IPX Net address
 *
 *      node:     IPX Node address
 *
 *      socket:      IPX socket address
 */
typedef struct {
        uint32_t        net;
        uint8_t         node[IPX_NODE_ADDR_LEN];
        uint16_t        socket;
} ascend_ipx_net_t;
 
/*
 *      ascend_ipx_filter_t
 *
 *      The binary format of an IPX filter.  ALL fields are stored in
 *      network byte order.
 *
 *      src:            Source net, node, and socket.
 *
 *      dst:            Destination net, node, and socket.
 *
 *      srcSocComp:     Source socket compare value
 *
 *      dstSocComp:     Destination socket compare value
 */
typedef struct {
        ascend_ipx_net_t src;
        ascend_ipx_net_t dst;
        uint8_t         srcSocComp;
        uint8_t         dstSocComp;
} ascend_ipx_filter_t;
 
 
/*
 *      ascend_generic_filter_t
 *
 *      The binary format of a GENERIC filter.  ALL fields are stored in
 *      network byte order.
 *
 *      offset:         Number of bytes into packet to start comparison.
 *
 *      len:            Number of bytes to mask and compare.  May not
 *                      exceed RAD_MAX_FILTER_LEN.
 *
 *      more:           Boolean.  If non-zero the next filter entry is
 *                      also to be applied to a packet.
 *
 *      mask:           A bit mask specifying the bits to compare.
 *
 *      value:          A value to compare against the masked bits at
 *                      offset in a users packet.
 *
 *      compNeq:        Defines type of comparison (Equal or Notequal)
 *                      default is Equal.
 *
 *      fill:           Round things out to a dword boundary
 */
typedef struct {
        uint16_t        offset;
        uint16_t        len;
        uint16_t        more;
        uint8_t         mask[ RAD_MAX_FILTER_LEN ];
        uint8_t         value[ RAD_MAX_FILTER_LEN ];
        uint8_t         compNeq;
} ascend_generic_filter_t;
 
/*
 *      ascend_filter_t
 *
 *      A binary filter element.  Contains one of ascend_ip_filter_t,
 *      ascend_ipx_filter_t, or ascend_generic_filter_t.
 *
 *      All fields are stored in network byte order.
 *
 *      type:           Either ASCEND_FILTER_GENERIC or ASCEND_FILTER_IP.
 *
 *      forward:        true if we should forward packets that match this
 *                      filter, false if we should drop packets that match
 *                      this filter.
 *
 *      direction:      true if this is an input filter, false if this is
 *                      an output filter.
 *
 *      fill:           Round things out to a dword boundary.
 *
 *      u:              A union of
 *                      ip:             An ip filter entry
 *                      generic:        A generic filter entry
 */
typedef struct {
        uint8_t         type;
        uint8_t         forward;
        uint8_t         direction;
        uint8_t         fill;
        union {
                ascend_ip_filter_t      ip;
                ascend_ipx_filter_t     ipx;
                ascend_ipv6_filter_t    ipv6;
                ascend_generic_filter_t generic;
        };
} ascend_filter_t;
 
/*
 * FilterPortType:
 *
 * Ascii names of some well known tcp/udp services.
 * Used for filtering on a port type.
 *
 * ??? What the heck is wrong with getservbyname?
 */
static fr_table_num_sorted_t const filterPortType[] = {
        { L("cmd"),     514 },
        { L("domain"),  53 },
        { L("exec"),    512 },
        { L("finger"),  79 },
        { L("ftp"),     21 },
        { L("ftp-data"),   20 },
        { L("gopher"),  70 },
        { L("hostname"),        101 },
        { L("kerberos"),        88 },
        { L("login"),   513 },
        { L("nameserver"), 42 },
        { L("nntp"),    119 },
        { L("ntp"),     123 },
        { L("smtp"),    25 },
        { L("talk"),    517 },
        { L("telnet"),  23 },
        { L("tftp"),    69 },
        { L("www"),     80 }
};
static size_t filterPortType_len = NUM_ELEMENTS(filterPortType);
 
static fr_table_num_sorted_t const filterType[] = {
        { L("generic"), ASCEND_FILTER_GENERIC},
        { L("ip"),      ASCEND_FILTER_IP},
        { L("ipv6"),    ASCEND_FILTER_IPV6},
        { L("ipx"),     ASCEND_FILTER_IPX},
};
static size_t filterType_len = NUM_ELEMENTS(filterType);
 
typedef enum : uint8_t {
        FILTER_IN,
        FILTER_OUT,
        FILTER_FORWARD,
        FILTER_DROP,
        FILTER_GENERIC_COMPNEQ,
        FILTER_GENERIC_COMPEQ,
        FILTER_MORE,
        FILTER_IP_DST,
        FILTER_IP_SRC,
        FILTER_IP_PROTO,
        FILTER_IP_DST_PORT,
        FILTER_IP_SRC_PORT,
        FILTER_EST,
        FILTER_IPX_DST_IPXNET,
        FILTER_IPX_DST_IPXNODE,
        FILTER_IPX_DST_IPXSOCK,
        FILTER_IPX_SRC_IPXNET,
        FILTER_IPX_SRC_IPXNODE,
        FILTER_IPX_SRC_IPXSOCK
} FilterTokens;
 
 
static fr_table_num_sorted_t const filterKeywords[] = {
        { L("!="),              FILTER_GENERIC_COMPNEQ },
        { L("=="),              FILTER_GENERIC_COMPEQ  },
        { L("drop"),            FILTER_DROP },
        { L("dstip"),           FILTER_IP_DST },
        { L("dstipxnet"),       FILTER_IPX_DST_IPXNET  },
        { L("dstipxnode"),      FILTER_IPX_DST_IPXNODE  },
        { L("dstipxsock"),      FILTER_IPX_DST_IPXSOCK  },
        { L("dstport"),         FILTER_IP_DST_PORT },
        { L("est"),             FILTER_EST },
        { L("forward"),         FILTER_FORWARD },
        { L("in"),              FILTER_IN },
        { L("more"),            FILTER_MORE },
        { L("out"),             FILTER_OUT },
        { L("srcip"),           FILTER_IP_SRC },
        { L("srcipxnet"),       FILTER_IPX_SRC_IPXNET  },
        { L("srcipxnode"),      FILTER_IPX_SRC_IPXNODE  },
        { L("srcipxsock"),      FILTER_IPX_SRC_IPXSOCK  },
        { L("srcport"), FILTER_IP_SRC_PORT }
};
static size_t filterKeywords_len = NUM_ELEMENTS(filterKeywords);
 
/*
 * FilterProtoName:
 *
 * Ascii name of protocols used for filtering.
 *
 *  ??? What the heck is wrong with getprotobyname?
 */
static fr_table_num_sorted_t const filterProtoName[] = {
        { L("0"),         0 },
        { L("icmp"), 1 },
        { L("ospf"), 89 },
        { L("tcp"),  6 },
        { L("udp"),  17 }
};
static size_t filterProtoName_len = NUM_ELEMENTS(filterProtoName);
 
 
/*
 * RadFilterComparison:
 *
 * An enumerated values for the IP filter port comparisons.
 */
typedef enum : uint8_t {
        RAD_NO_COMPARE = 0,
        RAD_COMPARE_LESS,
        RAD_COMPARE_EQUAL,
        RAD_COMPARE_GREATER,
        RAD_COMPARE_NOT_EQUAL
} RadFilterComparison;
 
static fr_table_num_sorted_t const filterCompare[] = {
        { L("!="), RAD_COMPARE_NOT_EQUAL        },
        { L("<"),       RAD_COMPARE_LESS        },
        { L("="),       RAD_COMPARE_EQUAL       },
        { L(">"),       RAD_COMPARE_GREATER     }
};
static size_t filterCompare_len = NUM_ELEMENTS(filterCompare);
 
/*
 *      ascend_parse_ipx_net
 *
 *      srcipxnet nnnn srcipxnode mmmmm [srcipxsoc cmd value ]
 */
static int ascend_parse_ipx_net(int argc, char **argv,
                                ascend_ipx_net_t *net, uint8_t *comp)
{
        int             token;
        fr_slen_t       slen;
        unsigned long   socket_num;
        char const      *p;
 
        if (argc < 3) {
                fr_strerror_const("Insufficient arguments to parse 'abinary' IPX network type");
                return -1;
        }
 
        /*
         *      Parse the net, which is a hex number.
         */
        net->net = htonl(strtol(argv[0], NULL, 16));
 
        /*
         *      Parse the node.
         */
        token = fr_table_value_by_str(filterKeywords, argv[1], -1);
        switch (token) {
        case FILTER_IPX_SRC_IPXNODE:
        case FILTER_IPX_DST_IPXNODE:
                break;
 
        default:
                fr_strerror_printf("Unknown keyword '%s' for IPX network filter", argv[1]);
                return -1;
        }
 
        /*
         *      Can have a leading "0x" or "0X"
         */
        p = argv[2];
        if ((memcmp(p, "0X", 2) == 0) ||
            (memcmp(p, "0x", 2) == 0)) p += 2;
 
        /*
         *      Node must be 6 octets long.
         */
        slen = fr_base16_decode(NULL,
                           &FR_DBUFF_TMP(net->node, IPX_NODE_ADDR_LEN),
                           &FR_SBUFF_IN_STR(p), false);
        if (slen != IPX_NODE_ADDR_LEN) {
                fr_strerror_printf("IPX network node name '%s' is the wrong size", argv[2]);
                return -1;
        }
 
        /*
         *      Nothing more, die.
         */
        if (argc == 3) return 3;
 
        /*
         *      Can't be too little or too much.
         */
        if (argc != 6) {
                fr_strerror_const("Insufficient arguments to parse 'abinary' IPX network type");
                return -1;
        }
 
        /*
         *      Parse the socket.
         */
        token = fr_table_value_by_str(filterKeywords, argv[3], -1);
        switch (token) {
        case FILTER_IPX_SRC_IPXSOCK:
        case FILTER_IPX_DST_IPXSOCK:
                break;
 
        default:
                fr_strerror_printf("Unknown keyword '%s' for IPX network filter", argv[3]);
                return -1;
        }
 
        /*
         *      Parse the command "<", ">", "=" or "!="
         */
        token = fr_table_value_by_str(filterCompare, argv[4], -1);
        switch (token) {
        case RAD_COMPARE_LESS:
        case RAD_COMPARE_EQUAL:
        case RAD_COMPARE_GREATER:
        case RAD_COMPARE_NOT_EQUAL:
                *comp = token;
                break;
 
        default:
                fr_strerror_printf("Unknown keyword '%s' for IPX network filter", argv[4]);
                return -1;
        }
 
        /*
         *      Parse the value.
         */
        socket_num = strtoul(argv[5], NULL, 16);
        if (socket_num > 65535) {
                fr_strerror_printf("Socket value '%s' is too large for IPX network filter", argv[5]);
                return -1;
        }
 
        net->socket = socket_num;
        net->socket = htons(net->socket);
 
 
        /*
         *      Everything's OK, we parsed 6 entries.
         */
        return 6;
}
 
/*
 *      ascend_parse_ipx_filter
 *
 *      This routine parses an IPX filter string from a string.
 *      The format of the string is:
 *
 *      [ srcipxnet nnnn srcipxnode mmmmm [srcipxsoc cmd value ]]
 *      [ dstipxnet nnnn dstipxnode mmmmm [dstipxsoc cmd value ]]
 *
 * Fields in [...] are optional.
 *      where:
 *
 *  srcipxnet:      Keyword for source IPX address.
 *                nnnn = IPX Node address.
 *
 *  srcipxnode:     Keyword for source IPX Node address.
 *                mmmmm = IPX Node Address, could be FFFFFF.
 *                A vlid ipx node number should accompany ipx net number.
 *
 *      srcipxsoc:      Keyword for source IPX socket address.
 *
 *      cmd:        One of ">" or "<" or "=" or "!=".
 *
 *      value:    Socket value to be compared against, in hex.
 *
 *      dstipxnet:      Keyword for destination IPX address.
 *                      nnnn = IPX Node address.
 *
 *      dstipxnode:     Keyword for destination IPX Node address.
 *              mmmmm = IPX Node Address, could be FFFFFF.
 *                     A valid ipx node number should accompany ipx net number.
 *
 *      dstipxsoc:      Keyword for destination IPX socket address.
 *
 *      cmd:            One of ">" or "<" or "=" or "!=".
 *
 *      value:          Socket value to be compared against, in hex.
 */
static int ascend_parse_ipx(int argc, char **argv, ascend_ipx_filter_t *filter)
{
        int slen;
        int token;
        int flags = 0;
 
        /*
         *      We may have nothing, in which case we simply return.
         */
        if (argc == 0) return 0;
 
        /*
         *      Must have "net N node M"
         */
        if (argc < 4) {
                fr_strerror_const("Insufficient arguments to parse 'abinary' IPX type");
                return -1;
        }
 
        while ((argc > 0) && (flags != 0x03)) {
                token = fr_table_value_by_str(filterKeywords, argv[0], -1);
                switch (token) {
                case FILTER_IPX_SRC_IPXNET:
                        if (flags & 0x01) {
duplicate:
                                fr_strerror_const("Duplicate field when parsing 'abinary' IPX type");
                                return -1;
                        }
                        slen = ascend_parse_ipx_net(argc - 1, argv + 1,
                                                     &(filter->src),
                                                     &(filter->srcSocComp));
                        if (slen < 0) return -1;
                        argc -= (slen + 1);
                        argv += slen + 1;
                        flags |= 0x01;
                        break;
 
                case FILTER_IPX_DST_IPXNET:
                        if (flags & 0x02) goto duplicate;
                        slen = ascend_parse_ipx_net(argc - 1, argv + 1,
                                                     &(filter->dst),
                                                     &(filter->dstSocComp));
                        if (slen < 0) return -1;
                        argc -= (slen + 1);
                        argv += slen + 1;
                        flags |= 0x02;
                        break;
 
                default:
                        fr_strerror_printf("Unknown string \"%s\" in IPX data filter",
                                   argv[0]);
                        return -1;
                }
        }
 
        /*
         *      Arguments left over: die.
         */
        if (argc != 0) {
                fr_strerror_const("Too many arguments to 'abinary' IPX filter");
                return -1;
        }
 
        /*
         *      Everything's OK.
         */
        return 0;
}
 
 
/*
 *      Parse an IP address and optionally a netmask, to a uint32_t.
 *
 *      ipaddr should already be initialized to zero.
 *      ipaddr is in network byte order.
 *
 *      Returns -1 on failure, or the number of bits in the netmask, otherwise.
 */
static int ascend_parse_ipaddr(uint32_t *ipaddr, char *str)
{
        int             count = 0;
        int             ip[4];
        int             masklen;
        bool            have_netmask = false;
        uint32_t        netmask = 0;
 
        /*
         *      Look for IP's.
         */
        count = 0;
        while (*str && (count < 4) && (netmask == 0)) {
        next:
                ip[count] = 0;
 
                while (*str) {
                        switch (*str) {
                        case '0': case '1': case '2': case '3':
                        case '4': case '5': case '6': case '7':
                        case '8': case '9':
                                ip[count] *= 10;
                                ip[count] += (*str) - '0';
                                str++;
                                break;
 
 
                        case '.': /* dot between IP numbers. */
                                str++;
                                if (ip[count] > 255) {
                                        fr_strerror_printf("Invalid IP address in '%s'", str);
                                        return -1;
                                }
 
                                /*
                                 *      24, 16, 8, 0, done.
                                 */
                                *ipaddr |= (ip[count] << (8 * (3 - count)));
                                count++;
                                goto next;
 
                        case '/': /* netmask  */
                                str++;
                                have_netmask = true;
                                masklen = atoi(str);
                                if ((masklen < 0) || (masklen > 32)) {
                                        fr_strerror_printf("Invalid mask in '%s'", str);
                                        return -1;
                                }
                                str += strspn(str, "0123456789");
                                netmask = masklen;
                                goto finalize;
 
                        default:
                                fr_strerror_const("Invalid character in IP address");
                                return -1;
                        }
                } /* loop over one character */
        } /* loop until the count hits 4 */
 
        if (count == 3) {
        finalize:
                /*
                 *      Do the last one, too.
                 */
                if (ip[count] > 255) {
                        fr_strerror_printf("Invalid mask in '%s'", str);
                        return -1;
                }
 
                /*
                 *      24, 16, 8, 0, done.
                 */
                *ipaddr |= (ip[count] << (8 * (3 - count)));
        }
 
        /*
         *      We've hit the end of the IP address, and there's something
         *      else left over: die.
         */
        if (*str) return -1;
 
        /*
         *      Set the default netmask.
         */
        if (!have_netmask) {
                if (!*ipaddr) {
                        netmask = 0;
                } else if ((*ipaddr & 0x80000000) == 0) {
                        netmask = 8;
                } else if ((*ipaddr & 0xc0000000) == 0x80000000) {
                        netmask = 16;
                } else if ((*ipaddr & 0xe0000000) == 0xc0000000) {
                        netmask = 24;
                } else {
                        netmask = 32;
                }
        }
 
        *ipaddr = htonl(*ipaddr);
        return netmask;
}
 
/*
 *      ascend_parse_port:  Parse a comparator and port.
 *
 *      Returns -1 on failure, or the comparator.
 */
static int ascend_parse_port(uint16_t *port, char *compare, char *str)
{
        int slen, token;
 
        /*
         *      There MUST be a comparison string.
         */
        slen = fr_table_value_by_str(filterCompare, compare, -1);
        if (slen < 0) {
                fr_strerror_printf("Unknown comparison operator '%s'", compare);
                return slen;
        }
 
        if (strspn(str, "0123456789") == strlen(str)) {
                token = atoi(str);
        } else {
                token = fr_table_value_by_str(filterPortType, str, -1);
        }
 
        if ((token < 0) || (token > 65535)) {
                fr_strerror_printf("Unknown port name '%s'", str);
                return -1;
        }
 
        *port = token;
        *port = htons(*port);
 
        return slen;
}
 
 
#define IP_SRC_ADDR_FLAG    (1 << 0)
#define IP_DEST_ADDR_FLAG   (1 << 1)
#define IP_SRC_PORT_FLAG    (1 << 2)
#define IP_DEST_PORT_FLAG   (1 << 3)
#define IP_PROTO_FLAG       (1 << 4)
#define IP_EST_FLAG      (1 << 5)
 
#define DONE_FLAGS      (IP_SRC_ADDR_FLAG | IP_DEST_ADDR_FLAG | \
                        IP_SRC_PORT_FLAG | IP_DEST_PORT_FLAG | \
                        IP_PROTO_FLAG | IP_EST_FLAG)
 
/*
 *      ascend_parse_ip:
 *
 *      This routine parses an IP filter string from a RADIUS
 *      reply. The format of the string is:
 *
 *      ip dir action [ dstip n.n.n.n/nn ] [ srcip n.n.n.n/nn ]
 *          [ proto [ dstport cmp value ] [ srcport cmd value ] [ est ] ]
 *
 *      Fields in [...] are optional.
 *
 *      dstip:          Keyword for destination IP address.
 *                      n.n.n.n = IP address. /nn - netmask.
 *
 *      srcip:          Keyword for source IP address.
 *                      n.n.n.n = IP address. /nn - netmask.
 *
 *      proto:          Optional protocol field. Either a name or
 *                      number. Known names are in FilterProtoName[].
 *
 *      dstport:        Keyword for destination port. Only valid with tcp
 *                      or udp. 'cmp' are in FilterPortType[]. 'value' can be
 *                      a name or number.
 *
 *      srcport:        Keyword for source port. Only valid with tcp
 *                      or udp. 'cmp' are in FilterPortType[]. 'value' can be
 *                      a name or number.
 *
 *      est:            Keyword for TCP established. Valid only for tcp.
 *
 */
static int ascend_parse_ip(int argc, char **argv, ascend_ip_filter_t *filter)
{
        int slen;
        int token;
        int flags;
 
        /*
         *      We may have nothing, in which case we simply return.
         */
        if (argc == 0) return 0;
 
        /*
         *      There may, or may not, be src & dst IP's in the string.
         */
        flags = 0;
        while ((argc > 0) && (flags != DONE_FLAGS)) {
                token = fr_table_value_by_str(filterKeywords, argv[0], -1);
                switch (token) {
                case FILTER_IP_SRC:
                        if (flags & IP_SRC_ADDR_FLAG) {
                        duplicate:
                                fr_strerror_printf("Duplicate field '%s' when parsing 'abinary' IP type", argv[0]);
                                return -1;
                        }
                        if (argc < 2) {
                        insufficient:
                                fr_strerror_printf("Insufficient arguments for '%s' when parsing 'abinary' IP type", argv[0]);
                                return -1;
                        }
 
                        slen = ascend_parse_ipaddr(&filter->srcip, argv[1]);
                        if (slen < 0) return slen;
 
                        filter->srcmask = slen;
                        flags |= IP_SRC_ADDR_FLAG;
                        argv += 2;
                        argc -= 2;
                        break;
 
                case FILTER_IP_DST:
                        if (flags & IP_DEST_ADDR_FLAG) goto duplicate;
                        if (argc < 2) goto insufficient;
 
                        slen = ascend_parse_ipaddr(&filter->dstip, argv[1]);
                        if (slen < 0) return slen;
 
                        filter->dstmask = slen;
                        flags |= IP_DEST_ADDR_FLAG;
                        argv += 2;
                        argc -= 2;
                        break;
 
                case FILTER_IP_SRC_PORT:
                        if (flags & IP_SRC_PORT_FLAG) goto duplicate;
                        if (argc < 3) goto insufficient;
 
                        slen = ascend_parse_port(&filter->srcport,
                                                  argv[1], argv[2]);
                        if (slen < 0) return slen;
                        filter->srcPortComp = slen;
 
                        flags |= IP_SRC_PORT_FLAG;
                        argv += 3;
                        argc -= 3;
                        break;
 
                case FILTER_IP_DST_PORT:
                        if (flags & IP_DEST_PORT_FLAG) goto duplicate;
                        if (argc < 3) goto insufficient;
 
                        slen = ascend_parse_port(&filter->dstport,
                                                  argv[1], argv[2]);
                        if (slen < 0) return slen;
                        filter->dstPortComp = slen;
 
                        flags |= IP_DEST_PORT_FLAG;
                        argv += 3;
                        argc -= 3;
                        break;
 
                case FILTER_EST:
                        if (flags & IP_EST_FLAG) goto duplicate;
                        filter->established = 1;
                        argv++;
                        argc--;
                        flags |= IP_EST_FLAG;
                        break;
 
                default:
                        if (flags & IP_PROTO_FLAG) goto duplicate;
                        if (strspn(argv[0], "0123456789") == strlen(argv[0])) {
                                token = atoi(argv[0]);
                        } else {
                                token = fr_table_value_by_str(filterProtoName, argv[0], -1);
                                if (token == -1) {
                                        fr_strerror_printf("Unknown IP protocol \"%s\" in IP data filter",
                                                   argv[0]);
                                        return -1;
                                }
                        }
                        if (token > UINT8_MAX) {
                                fr_strerror_printf("IP protocol \"%s\" is too large in IP data filter", argv[0]);
                                return -1;
                        }
                        filter->proto = token;
                        flags |= IP_PROTO_FLAG;
 
                        argv++;
                        argc--;
                        break;
                }
        }
 
        /*
         *      We should have parsed everything by now.
         */
        if (argc != 0) {
                fr_strerror_printf("Unknown extra string \"%s\" in IP data filter",
                           argv[0]);
                return -1;
        }
 
        return 0;
}
 
/*
 *      ascend_parse_ipv6:
 *
 *      Exactly like ascend_parse_ip(), but allows for IPv6 addresses.
 *
 *      From https://www.juniper.net/documentation/en_US/junos/topics/reference/general/ascend-data-filter-fields.html
 */
static int ascend_parse_ipv6(int argc, char **argv, ascend_ipv6_filter_t *filter)
{
        int slen;
        int token;
        int flags;
 
        /*
         *      We may have nothing, in which case we simply return.
         */
        if (argc == 0) return 0;
 
        /*
         *      There may, or may not, be src & dst IP's in the string.
         */
        flags = 0;
        while ((argc > 0) && (flags != DONE_FLAGS)) {
                fr_ipaddr_t ipaddr;
 
                token = fr_table_value_by_str(filterKeywords, argv[0], -1);
                switch (token) {
                case FILTER_IP_SRC:
                        if (flags & IP_SRC_ADDR_FLAG) {
                        duplicate:
                                fr_strerror_printf("Duplicate field '%s' when parsing 'abinary' IPv6 type", argv[0]);
                                return -1;
                        }
                        if (argc < 2) {
                        insufficient:
                                fr_strerror_printf("Insufficient arguments for '%s' when parsing 'abinary' IPv6 type", argv[0]);
                                return -1;
                        }
 
                        if (fr_inet_pton6(&ipaddr, argv[1], strlen(argv[1]), false, false, true) < 0) return -1;
                        memcpy(&filter->srcip, ipaddr.addr.v6.s6_addr, 16);
                        filter->srcmask = ipaddr.prefix;
 
                        flags |= IP_SRC_ADDR_FLAG;
                        argv += 2;
                        argc -= 2;
                        break;
 
                case FILTER_IP_DST:
                        if (flags & IP_DEST_ADDR_FLAG) goto duplicate;
                        if (argc < 2) goto insufficient;
 
                        if (fr_inet_pton6(&ipaddr, argv[1], strlen(argv[1]), false, false, true) < 0) return -1;
                        memcpy(&filter->dstip, ipaddr.addr.v6.s6_addr, 16);
                        filter->dstmask = ipaddr.prefix;
 
                        flags |= IP_DEST_ADDR_FLAG;
                        argv += 2;
                        argc -= 2;
                        break;
 
                case FILTER_IP_SRC_PORT:
                        if (flags & IP_SRC_PORT_FLAG) goto duplicate;
                        if (argc < 3) goto insufficient;
 
                        slen = ascend_parse_port(&filter->srcport,
                                                  argv[1], argv[2]);
                        if (slen < 0) return slen;
                        filter->srcPortComp = slen;
 
                        flags |= IP_SRC_PORT_FLAG;
                        argv += 3;
                        argc -= 3;
                        break;
 
                case FILTER_IP_DST_PORT:
                        if (flags & IP_DEST_PORT_FLAG) goto duplicate;
                        if (argc < 3) goto insufficient;
 
                        slen = ascend_parse_port(&filter->dstport,
                                                  argv[1], argv[2]);
                        if (slen < 0) return slen;
                        filter->dstPortComp = slen;
 
                        flags |= IP_DEST_PORT_FLAG;
                        argv += 3;
                        argc -= 3;
                        break;
 
                case FILTER_EST:
                        if (flags & IP_EST_FLAG) goto duplicate;
                        filter->established = 1;
                        argv++;
                        argc--;
                        flags |= IP_EST_FLAG;
                        break;
 
                default:
                        if (flags & IP_PROTO_FLAG) goto duplicate;
                        if (strspn(argv[0], "0123456789") == strlen(argv[0])) {
                                token = atoi(argv[0]);
                        } else {
                                token = fr_table_value_by_str(filterProtoName, argv[0], -1);
                                if (token == -1) {
                                        fr_strerror_printf("Unknown IPv6 protocol \"%s\" in IP data filter",
                                                   argv[0]);
                                        return -1;
                                }
                        }
                        if (token > UINT8_MAX) {
                                fr_strerror_printf("IPv6 protocol \"%s\" is too large in IP data filter", argv[0]);
                                return -1;
                        }
                        filter->proto = token;
                        flags |= IP_PROTO_FLAG;
 
                        argv++;
                        argc--;
                        break;
                }
        }
 
        /*
         *      We should have parsed everything by now.
         */
        if (argc != 0) {
                fr_strerror_printf("Unknown extra string \"%s\" in IPv6 data filter",
                           argv[0]);
                return -1;
        }
 
        return 0;
}
 
 
/*
 *      ascend_parse_generic
 *
 *      This routine parses a Generic filter string from a RADIUS
 *      reply. The format of the string is:
 *
 *      generic dir action offset mask value [== or != ] [more]
 *
 *      Fields in [...] are optional.
 *
 *      offset:         A Number. Specifies an offset into a frame
 *                      to start comparing.
 *
 *      mask:           A hexadecimal mask of bits to compare.
 *
 *      value:          A value to compare with the masked data.
 *
 *      compNeq:        Defines type of comparison. ( "==" or "!=")
 *                      Default is "==".
 *
 *      more:           Optional keyword MORE, to represent the attachment
 *                      to the next entry.
 */
static int ascend_parse_generic(int argc, char **argv,
                                ascend_generic_filter_t *filter)
{
        unsigned long offset;
        fr_slen_t slen;
        fr_slen_t value_slen;
        int token;
        int flags;
 
        /*
         *      We may have nothing, in which case we simply return.
         */
        if (argc == 0) return 0;
 
        /*
         *      We need at least "offset mask value"
         */
        if (argc < 3) {
                fr_strerror_const("Insufficient arguments to parse 'abinary' generic type");
                return -1;
        }
 
        /*
         *      No more than optional comparison and "more"
         */
        if (argc > 5) {
                fr_strerror_const("Too many arguments to parse 'abinary' generic type");
                return -1;
        }
 
        /*
         *      Offset is a uint16_t number.
         */
        if (strspn(argv[0], "0123456789") != strlen(argv[0])) {
        invalid:
                fr_strerror_printf("Invalid offset '%s'", argv[0]);
                return -1;
        }
 
        offset = strtoul(argv[0], NULL, 10);
        if (offset > UINT16_MAX) goto invalid;
 
        filter->offset = offset;
        filter->offset = htons(filter->offset);
 
        slen = fr_base16_decode(NULL,
                           &FR_DBUFF_TMP(filter->mask, sizeof(filter->mask)),
                           &FR_SBUFF_IN_STR(argv[1]), false);
        if (slen != sizeof(filter->mask)) {
                fr_strerror_printf("Invalid filter mask '%s'", argv[1]);
                return -1;
        }
 
        value_slen = fr_base16_decode(NULL,
                           &FR_DBUFF_TMP(filter->value, sizeof(filter->value)),
                           &FR_SBUFF_IN_STR(argv[2]), false);
        if (value_slen != sizeof(filter->value)) {
                fr_strerror_printf("Invalid filter mask '%s'", argv[1]);
                return -1;
        }
 
        filter->len = slen;
        filter->len = htons(filter->len);
 
        /*
         *      Nothing more.  Exit.
         */
        if (argc == 3) return 0;
 
        argc -= 3;
        argv += 3;
        flags = 0;
 
        while (argc >= 1) {
                token = fr_table_value_by_str(filterKeywords, argv[0], -1);
                switch (token) {
                case FILTER_GENERIC_COMPNEQ:
                        if (flags & 0x01) {
                        duplicate:
                                fr_strerror_printf("Duplicate field '%s' when parsing 'abinary' generic type", argv[0]);
                                return -1;
                        }
                        filter->compNeq = true;
                        flags |= 0x01;
                        break;
                case FILTER_GENERIC_COMPEQ:
                        if (flags & 0x01) goto duplicate;
                        filter->compNeq = false;
                        flags |= 0x01;
                        break;
 
                case FILTER_MORE:
                        if (flags & 0x02) goto duplicate;
                        filter->more = htons( 1 );
                        flags |= 0x02;
                        break;
 
                default:
                        fr_strerror_printf("Invalid string \"%s\" in generic data filter",
                                   argv[0]);
                        return -1;
                }
 
                argc--;
                argv++;
        }
 
        return 0;
}
 
 
/** Encode a string to abinary.
 *
 * This routine will call routines to parse entries from an ASCII format
 * to a binary format recognized by the Ascend boxes.
 *
 * @param vp    VP to encode
 * @param dbuff where to write the VP data
 * @return
 *      - >0 on success == size of the data encoded
 *      - <=0 on failure, which is the size needed to encode the data
 */
ssize_t fr_radius_encode_abinary(fr_pair_t const *vp, fr_dbuff_t *dbuff)
{
        int             token, type;
        int             slen = 0;
        int             argc;
        char            *argv[32];
        ascend_filter_t filter;
        char            *p;
        size_t          size = 0;
 
        /*
         *      Tokenize the input string in the VP.
         *
         *      Once the filter is *completely* parsed, then we will
         *      over-write it with the final binary filter.
         */
        p = talloc_bstrndup(NULL, vp->vp_strvalue, vp->vp_length);
 
        argc = fr_dict_str_to_argv(p, argv, 32);
        if (argc < 3) {
                fr_strerror_const("Insufficient arguments to parse 'abinary' type");
        fail:
                talloc_free(p);
                return 0;
        }
 
        /*
         *      Decide which filter type it is: ip, ipx, or generic
         */
        type = fr_table_value_by_str(filterType, argv[0], -1);
        memset(&filter, 0, sizeof(filter));
 
        /*
         *      Validate the filter type.
         */
        switch (type) {
        case ASCEND_FILTER_GENERIC:
        case ASCEND_FILTER_IP:
        case ASCEND_FILTER_IPX:
        case ASCEND_FILTER_IPV6:
                filter.type = type;
                break;
 
        default:
                fr_strerror_printf("Unknown Ascend filter type \"%s\"", argv[0]);
                goto fail;
        }
 
        /*
         *      Parse direction
         */
        token = fr_table_value_by_str(filterKeywords, argv[1], -1);
        switch (token) {
        case FILTER_IN:
                filter.direction = 1;
                break;
 
        case FILTER_OUT:
                filter.direction = 0;
                break;
 
        default:
                fr_strerror_printf("Unknown Ascend filter direction \"%s\"", argv[1]);
                goto fail;
        }
 
        /*
         *      Parse action
         */
        token = fr_table_value_by_str(filterKeywords, argv[2], -1);
        switch (token) {
        case FILTER_FORWARD:
                filter.forward = 1;
                break;
 
        case FILTER_DROP:
                filter.forward = 0;
                break;
 
        default:
                fr_strerror_printf("Unknown Ascend filter action \"%s\"", argv[2]);
                goto fail;
        }
 
        switch (type) {
        case ASCEND_FILTER_GENERIC:
                slen = ascend_parse_generic(argc - 3, &argv[3], &filter.generic);
                size = 32;
                break;
 
        case ASCEND_FILTER_IP:
                slen = ascend_parse_ip(argc - 3, &argv[3], &filter.ip);
                size = 32;
                break;
 
        case ASCEND_FILTER_IPX:
                slen = ascend_parse_ipx(argc - 3, &argv[3], &filter.ipx);
                size = 32;
                break;
 
        case ASCEND_FILTER_IPV6:
                slen = ascend_parse_ipv6(argc - 3, &argv[3], &filter.ipv6);
                size = sizeof(filter);
                break;
        }
 
        if (slen < 0) goto fail;
 
        talloc_free(p);
 
        return fr_dbuff_in_memcpy(dbuff, (uint8_t *)&filter, size);
}
 
/** Print an Ascend binary filter attribute to a string,
 *
 * Grrr... Ascend makes the server do this work, instead of doing it on the NAS.
 *
 * @param[in,out] vp    Where the decoded string will be stored.
 * @param[in] data      binary data to decodee
 * @param[in] data_len  length of the binary data to decodee
 * @return
 *      - 0 OK
 *      - <0 on error.  VP is untouched.
 */
ssize_t fr_radius_decode_abinary(fr_pair_t *vp, uint8_t const *data, size_t data_len)
{
        ascend_filter_t const   *filter;
        size_t                  size;
        fr_ipaddr_t             ipaddr;
        char                    buffer[FR_IPADDR_PREFIX_STRLEN];
        char                    string[256];
        fr_sbuff_t              sbuff = FR_SBUFF_OUT(string, sizeof(string));
        uint64_t                aligned[256 / sizeof(uint64_t)];
 
        static char const *action[] = {"drop", "forward"};
        static char const *direction[] = {"out", "in"};
 
        /*
         *  Just for paranoia: wrong size filters get printed as octets
         */
        if (data_len < 4) return -1;
 
        /*
         *      ascend data filters aren't concatenated across
         *      multiple RADIUS attributes.
         */
        if (data_len > RADIUS_MAX_STRING_LENGTH) return -1;
 
        memcpy(aligned, data, data_len);
 
        filter = (ascend_filter_t const *) aligned;
 
        switch ((ascend_filter_type_t)filter->type) {
        case ASCEND_FILTER_IP:
                size = sizeof(filter->ip);
                break;
 
        case ASCEND_FILTER_IPX:
                size = sizeof(filter->ipx);
                break;
 
        case ASCEND_FILTER_GENERIC:
                size = sizeof(filter->generic);
                break;
 
        case ASCEND_FILTER_IPV6:
                size = sizeof(filter->ipv6);
                break;
 
        default:
                return -1;
        }
 
        /*
         *      Account for the 4 octet header, too.
         */
        if (data_len < (4 + size)) return -size;
 
        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, "%s %s %s", fr_table_str_by_value(filterType, filter->type, "??"),
                                   direction[filter->direction & 0x01], action[filter->forward & 0x01]);
 
        switch ((ascend_filter_type_t)filter->type) {
 
        /*
         *      Handle IP filters
         */
        case ASCEND_FILTER_IP:
                if (filter->ip.srcip) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " srcip %d.%d.%d.%d/%d",
                                                   ((uint8_t const *) &filter->ip.srcip)[0],
                                                   ((uint8_t const *) &filter->ip.srcip)[1],
                                                   ((uint8_t const *) &filter->ip.srcip)[2],
                                                   ((uint8_t const *) &filter->ip.srcip)[3],
                                                   filter->ip.srcmask);
                }
 
                if (filter->ip.dstip) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " dstip %d.%d.%d.%d/%d",
                                                   ((uint8_t const *) &filter->ip.dstip)[0],
                                                   ((uint8_t const *) &filter->ip.dstip)[1],
                                                   ((uint8_t const *) &filter->ip.dstip)[2],
                                                   ((uint8_t const *) &filter->ip.dstip)[3],
                                                   filter->ip.dstmask);
                }
 
                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " %s", fr_table_str_by_value(filterProtoName, filter->ip.proto, "??"));
 
                if (filter->ip.srcPortComp > RAD_NO_COMPARE) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " srcport %s %d",
                                                   fr_table_str_by_value(filterCompare, filter->ip.srcPortComp, "??"),
                                                   ntohs(filter->ip.srcport));
                }
 
                if (filter->ip.dstPortComp > RAD_NO_COMPARE) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " dstport %s %d",
                                                   fr_table_str_by_value(filterCompare, filter->ip.dstPortComp, "??"),
                                                   ntohs(filter->ip.dstport));
                }
 
                if (filter->ip.established) {
                        FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " est");
                }
                break;
 
        /*
         *      Handle IPX filters
         */
        case ASCEND_FILTER_IPX:
                /* print for source */
                if (filter->ipx.src.net) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " srcipxnet 0x%04x srcipxnode 0x%02x%02x%02x%02x%02x%02x",
                                                   (unsigned int)ntohl(filter->ipx.src.net),
                                                   filter->ipx.src.node[0], filter->ipx.src.node[1],
                                                   filter->ipx.src.node[2], filter->ipx.src.node[3],
                                                   filter->ipx.src.node[4], filter->ipx.src.node[5]);
 
                        if (filter->ipx.srcSocComp > RAD_NO_COMPARE) {
                                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " srcipxsock %s 0x%04x",
                                                           fr_table_str_by_value(filterCompare, filter->ipx.srcSocComp, "??"),
                                                           ntohs(filter->ipx.src.socket));
                        }
                }
 
                /* same for destination */
                if (filter->ipx.dst.net) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " dstipxnet 0x%04x dstipxnode 0x%02x%02x%02x%02x%02x%02x",
                                                   (unsigned int)ntohl(filter->ipx.dst.net),
                                                   filter->ipx.dst.node[0], filter->ipx.dst.node[1],
                                                   filter->ipx.dst.node[2], filter->ipx.dst.node[3],
                                                   filter->ipx.dst.node[4], filter->ipx.dst.node[5]);
 
                        if (filter->ipx.dstSocComp > RAD_NO_COMPARE) {
                                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " dstipxsock %s 0x%04x",
                                                           fr_table_str_by_value(filterCompare, filter->ipx.dstSocComp, "??"),
                                                           ntohs(filter->ipx.dst.socket));
                        }
                }
                break;
 
        case ASCEND_FILTER_GENERIC:
        {
                size_t i, len;
 
                /*
                 *      Why is len 16 bits, when the masks are only 6 bytes?
                 */
                len = ntohs(filter->generic.len);
                if (len > sizeof(filter->generic.mask)) {
                        return -size;
                }
 
                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " %u ", (unsigned int) ntohs(filter->generic.offset));
 
                /* show the mask */
                for (i = 0; i < len; i++) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, "%02x", filter->generic.mask[i]);
                }
 
                FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " ");
 
                /* show the value */
                for (i = 0; i < len; i++) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, "%02x", filter->generic.value[i]);
                }
 
                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " %s", (filter->generic.compNeq) ? "!=" : "==");
 
                if (filter->generic.more != 0) {
                        FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " more");
                }
        }
                break;
 
        /*
         *      Handle IPv6 filters
         */
        case ASCEND_FILTER_IPV6:
                /*
                 *      srcip
                 */
                memset(&ipaddr, 0, sizeof(ipaddr));
                ipaddr.af = AF_INET6;
                memcpy(&ipaddr.addr.v6.s6_addr, filter->ipv6.srcip, sizeof(filter->ipv6.srcip));
                ipaddr.prefix = filter->ipv6.srcmask;
 
                FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " srcip ");
 
                (void) fr_inet_ntop_prefix(buffer, sizeof(buffer), &ipaddr);
                FR_SBUFF_IN_STRCPY_RETURN(&sbuff, buffer);
 
                /*
                 *      dstip
                 */
                memset(&ipaddr, 0, sizeof(ipaddr));
                ipaddr.af = AF_INET6;
                memcpy(&ipaddr.addr.v6.s6_addr, filter->ipv6.dstip, sizeof(filter->ipv6.dstip));
                ipaddr.prefix = filter->ipv6.dstmask;
 
                FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " dstip ");
 
                (void) fr_inet_ntop_prefix(buffer, sizeof(buffer), &ipaddr);
                FR_SBUFF_IN_STRCPY_RETURN(&sbuff, buffer);
 
                FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " %s", fr_table_str_by_value(filterProtoName, filter->ipv6.proto, "??"));
 
                if (filter->ipv6.srcPortComp > RAD_NO_COMPARE) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " srcport %s %d",
                                                   fr_table_str_by_value(filterCompare, filter->ipv6.srcPortComp, "??"),
                                                   ntohs(filter->ipv6.srcport));
                }
 
                if (filter->ipv6.dstPortComp > RAD_NO_COMPARE) {
                        FR_SBUFF_IN_SPRINTF_RETURN(&sbuff, " dstport %s %d",
                                                   fr_table_str_by_value(filterCompare, filter->ipv6.dstPortComp, "??"),
                                                   ntohs(filter->ipv6.dstport));
                }
 
                if (filter->ipv6.established) {
                        FR_SBUFF_IN_STRCPY_RETURN(&sbuff, " est");
                }
                break;
 
        default:
                break;
        }
 
        /*
         *      Copy the finished string to the output VP.
         */
        if (fr_pair_value_strdup(vp, string, true) < 0) return -1;
 
        return 0;
}