/*
 * utils.c
 *
 *              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.
 *
 * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <unistd.h>
#include <fcntl.h>
#include <limits.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <ctype.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <asm/types.h>
#include <linux/pkt_sched.h>
#include <linux/param.h>
#include <linux/if_arp.h>
#include <linux/mpls.h>
#include <linux/snmp.h>
#include <time.h>
#include <sys/time.h>
#include <errno.h>
#ifdef HAVE_LIBCAP
#include <sys/capability.h>
#endif

#include "rt_names.h"
#include "utils.h"
#include "ll_map.h"
#include "namespace.h"

int resolve_hosts;
int timestamp_short;
int pretty;
const char *_SL_ = "\n";

static int af_byte_len(int af);
static void print_time(char *buf, int len, __u32 time);
static void print_time64(char *buf, int len, __s64 time);

int read_prop(const char *dev, char *prop, long *value)
{
        char fname[128], buf[80], *endp, *nl;
        FILE *fp;
        long result;
        int ret;

        ret = snprintf(fname, sizeof(fname), "/sys/class/net/%s/%s",
                        dev, prop);

        if (ret <= 0 || ret >= sizeof(fname)) {
                fprintf(stderr, "could not build pathname for property\n");
                return -1;
        }

        fp = fopen(fname, "r");
        if (fp == NULL) {
                fprintf(stderr, "fopen %s: %s\n", fname, strerror(errno));
                return -1;
        }

        if (!fgets(buf, sizeof(buf), fp)) {
                fprintf(stderr, "property \"%s\" in file %s is currently unknown\n", prop, fname);
                fclose(fp);
                goto out;
        }

        nl = strchr(buf, '\n');
        if (nl)
                *nl = '\0';

        fclose(fp);
        result = strtol(buf, &endp, 0);

        if (*endp || buf == endp) {
                fprintf(stderr, "value \"%s\" in file %s is not a number\n",
                        buf, fname);
                goto out;
        }

        if ((result == LONG_MAX || result == LONG_MIN) && errno == ERANGE) {
                fprintf(stderr, "strtol %s: %s", fname, strerror(errno));
                goto out;
        }

        *value = result;
        return 0;
out:
        fprintf(stderr, "Failed to parse %s\n", fname);
        return -1;
}

int get_hex(char c)
{
        if (c >= 'A' && c <= 'F')
                return c - 'A' + 10;
        if (c >= 'a' && c <= 'f')
                return c - 'a' + 10;
        if (c >= '0' && c <= '9')
                return c - '0';

        return -1;
}

int get_integer(int *val, const char *arg, int base)
{
        long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;

        res = strtol(arg, &ptr, base);

        /* If there were no digits at all, strtol()  stores
         * the original value of nptr in *endptr (and returns 0).
         * In particular, if *nptr is not '\0' but **endptr is '\0' on return,
         * the entire string is valid.
         */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* If an underflow occurs, strtol() returns LONG_MIN.
         * If an overflow occurs,  strtol() returns LONG_MAX.
         * In both cases, errno is set to ERANGE.
         */
        if ((res == LONG_MAX || res == LONG_MIN) && errno == ERANGE)
                return -1;

        /* Outside range of int */
        if (res < INT_MIN || res > INT_MAX)
                return -1;

        *val = res;
        return 0;
}

int mask2bits(__u32 netmask)
{
        unsigned int bits = 0;
        __u32 mask = ntohl(netmask);
        __u32 host = ~mask;

        /* a valid netmask must be 2^n - 1 */
        if ((host & (host + 1)) != 0)
                return -1;

        for (; mask; mask <<= 1)
                ++bits;
        return bits;
}

static int get_netmask(unsigned int *val, const char *arg, int base)
{
        inet_prefix addr;

        if (!get_unsigned(val, arg, base))
                return 0;

        /* try converting dotted quad to CIDR */
        if (!get_addr_1(&addr, arg, AF_INET) && addr.family == AF_INET) {
                int b = mask2bits(addr.data[0]);

                if (b >= 0) {
                        *val = b;
                        return 0;
                }
        }

        return -1;
}

int get_unsigned(unsigned int *val, const char *arg, int base)
{
        unsigned long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;

        res = strtoul(arg, &ptr, base);

        /* empty string or trailing non-digits */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* overflow */
        if (res == ULONG_MAX && errno == ERANGE)
                return -1;

        /* out side range of unsigned */
        if (res > UINT_MAX)
                return -1;

        *val = res;
        return 0;
}

/*
 * get_time_rtt is "translated" from a similar routine "get_time" in
 * tc_util.c.  We don't use the exact same routine because tc passes
 * microseconds to the kernel and the callers of get_time_rtt want to
 * pass milliseconds (standard unit for rtt values since 2.6.27), and
 * have a different assumption for the units of a "raw" number.
 */
int get_time_rtt(unsigned int *val, const char *arg, int *raw)
{
        double t;
        unsigned long res;
        char *p;

        if (strchr(arg, '.') != NULL) {
                t = strtod(arg, &p);
                if (t < 0.0)
                        return -1;

                /* no digits? */
                if (!p || p == arg)
                        return -1;

                /* over/underflow */
                if ((t == HUGE_VALF || t == HUGE_VALL) && errno == ERANGE)
                        return -1;
        } else {
                res = strtoul(arg, &p, 0);

                /* empty string? */
                if (!p || p == arg)
                        return -1;

                /* overflow */
                if (res == ULONG_MAX && errno == ERANGE)
                        return -1;

                t = (double)res;
        }

        if (p == arg)
                return -1;
        *raw = 1;

        if (*p) {
                *raw = 0;
                if (strcasecmp(p, "s") == 0 ||
                    strcasecmp(p, "sec") == 0 ||
                    strcasecmp(p, "secs") == 0)
                        t *= 1000;
                else if (strcasecmp(p, "ms") == 0 ||
                         strcasecmp(p, "msec") == 0 ||
                         strcasecmp(p, "msecs") == 0)
                        t *= 1.0; /* allow suffix, do nothing */
                else
                        return -1;
        }

        /* emulate ceil() without having to bring-in -lm and always be >= 1 */
        *val = t;
        if (*val < t)
                *val += 1;

        return 0;

}

int get_u64(__u64 *val, const char *arg, int base)
{
        unsigned long long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;

        res = strtoull(arg, &ptr, base);

        /* empty string or trailing non-digits */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* overflow */
        if (res == ULLONG_MAX && errno == ERANGE)
                return -1;

        /* in case ULL is 128 bits */
        if (res > 0xFFFFFFFFFFFFFFFFULL)
                return -1;

        *val = res;
        return 0;
}

int get_u32(__u32 *val, const char *arg, int base)
{
        unsigned long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;
        res = strtoul(arg, &ptr, base);

        /* empty string or trailing non-digits */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* overflow */
        if (res == ULONG_MAX && errno == ERANGE)
                return -1;

        /* in case UL > 32 bits */
        if (res > 0xFFFFFFFFUL)
                return -1;

        *val = res;
        return 0;
}

int get_u16(__u16 *val, const char *arg, int base)
{
        unsigned long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;
        res = strtoul(arg, &ptr, base);

        /* empty string or trailing non-digits */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* overflow */
        if (res == ULONG_MAX && errno == ERANGE)
                return -1;

        if (res > 0xFFFFUL)
                return -1;

        *val = res;
        return 0;
}

int get_u8(__u8 *val, const char *arg, int base)
{
        unsigned long res;
        char *ptr;

        if (!arg || !*arg)
                return -1;

        res = strtoul(arg, &ptr, base);
        /* empty string or trailing non-digits */
        if (!ptr || ptr == arg || *ptr)
                return -1;

        /* overflow */
        if (res == ULONG_MAX && errno == ERANGE)
                return -1;

        if (res > 0xFFUL)
                return -1;

        *val = res;
        return 0;
}

int get_s64(__s64 *val, const char *arg, int base)
{
        long long res;
        char *ptr;

        errno = 0;

        if (!arg || !*arg)
                return -1;
        res = strtoll(arg, &ptr, base);
        if (!ptr || ptr == arg || *ptr)
                return -1;
        if ((res == LLONG_MIN || res == LLONG_MAX) && errno == ERANGE)
                return -1;
        if (res > INT64_MAX || res < INT64_MIN)
                return -1;

        *val = res;
        return 0;
}

int get_s32(__s32 *val, const char *arg, int base)
{
        long res;
        char *ptr;

        errno = 0;

        if (!arg || !*arg)
                return -1;
        res = strtol(arg, &ptr, base);
        if (!ptr || ptr == arg || *ptr)
                return -1;
        if ((res == LONG_MIN || res == LONG_MAX) && errno == ERANGE)
                return -1;
        if (res > INT32_MAX || res < INT32_MIN)
                return -1;

        *val = res;
        return 0;
}

int get_be64(__be64 *val, const char *arg, int base)
{
        __u64 v;
        int ret = get_u64(&v, arg, base);

        if (!ret)
                *val = htonll(v);

        return ret;
}

int get_be32(__be32 *val, const char *arg, int base)
{
        __u32 v;
        int ret = get_u32(&v, arg, base);

        if (!ret)
                *val = htonl(v);

        return ret;
}

int get_be16(__be16 *val, const char *arg, int base)
{
        __u16 v;
        int ret = get_u16(&v, arg, base);

        if (!ret)
                *val = htons(v);

        return ret;
}

/* This uses a non-standard parsing (ie not inet_aton, or inet_pton)
 * because of legacy choice to parse 10.8 as 10.8.0.0 not 10.0.0.8
 */
static int get_addr_ipv4(__u8 *ap, const char *cp)
{
        int i;

        for (i = 0; i < 4; i++) {
                unsigned long n;
                char *endp;

                n = strtoul(cp, &endp, 0);
                if (n > 255)
                        return -1;      /* bogus network value */

                if (endp == cp) /* no digits */
                        return -1;

                ap[i] = n;

                if (*endp == '\0')
                        break;

                if (i == 3 || *endp != '.')
                        return -1;      /* extra characters */
                cp = endp + 1;
        }

        return 1;
}

int get_addr64(__u64 *ap, const char *cp)
{
        int i;

        union {
                __u16 v16[4];
                __u64 v64;
        } val;

        for (i = 0; i < 4; i++) {
                unsigned long n;
                char *endp;

                n = strtoul(cp, &endp, 16);
                if (n > 0xffff)
                        return -1;      /* bogus network value */

                if (endp == cp) /* no digits */
                        return -1;

                val.v16[i] = htons(n);

                if (*endp == '\0')
                        break;

                if (i == 3 || *endp != ':')
                        return -1;      /* extra characters */
                cp = endp + 1;
        }

        *ap = val.v64;

        return 1;
}

static void set_address_type(inet_prefix *addr)
{
        switch (addr->family) {
        case AF_INET:
                if (!addr->data[0])
                        addr->flags |= ADDRTYPE_INET_UNSPEC;
                else if (IN_MULTICAST(ntohl(addr->data[0])))
                        addr->flags |= ADDRTYPE_INET_MULTI;
                else
                        addr->flags |= ADDRTYPE_INET;
                break;
        case AF_INET6:
                if (IN6_IS_ADDR_UNSPECIFIED(addr->data))
                        addr->flags |= ADDRTYPE_INET_UNSPEC;
                else if (IN6_IS_ADDR_MULTICAST(addr->data))
                        addr->flags |= ADDRTYPE_INET_MULTI;
                else
                        addr->flags |= ADDRTYPE_INET;
                break;
        }
}

static int __get_addr_1(inet_prefix *addr, const char *name, int family)
{
        memset(addr, 0, sizeof(*addr));

        if (strcmp(name, "default") == 0) {
                if (family == AF_MPLS)
                        return -1;
                addr->family = family;
                addr->bytelen = af_byte_len(addr->family);
                addr->bitlen = -2;
                addr->flags |= PREFIXLEN_SPECIFIED;
                return 0;
        }

        if (strcmp(name, "all") == 0 ||
            strcmp(name, "any") == 0) {
                if (family == AF_MPLS)
                        return -1;
                addr->family = family;
                addr->bytelen = 0;
                addr->bitlen = -2;
                return 0;
        }

        if (family == AF_PACKET) {
                int len;

                len = ll_addr_a2n((char *) &addr->data, sizeof(addr->data),
                                  name);
                if (len < 0)
                        return -1;

                addr->family = AF_PACKET;
                addr->bytelen = len;
                addr->bitlen = len * 8;
                return 0;
        }

        if (strchr(name, ':')) {
                addr->family = AF_INET6;
                if (family != AF_UNSPEC && family != AF_INET6)
                        return -1;
                if (inet_pton(AF_INET6, name, addr->data) <= 0)
                        return -1;
                addr->bytelen = 16;
                addr->bitlen = -1;
                return 0;
        }

        if (family == AF_MPLS) {
                unsigned int maxlabels;
                int i;

                addr->family = AF_MPLS;
                if (mpls_pton(AF_MPLS, name, addr->data,
                              sizeof(addr->data)) <= 0)
                        return -1;
                addr->bytelen = 4;
                addr->bitlen = 20;
                /* How many bytes do I need? */
                maxlabels = sizeof(addr->data) / sizeof(struct mpls_label);
                for (i = 0; i < maxlabels; i++) {
                        if (ntohl(addr->data[i]) & MPLS_LS_S_MASK) {
                                addr->bytelen = (i + 1)*4;
                                break;
                        }
                }
                return 0;
        }

        addr->family = AF_INET;
        if (family != AF_UNSPEC && family != AF_INET)
                return -1;

        if (get_addr_ipv4((__u8 *)addr->data, name) <= 0)
                return -1;

        addr->bytelen = 4;
        addr->bitlen = -1;
        return 0;
}

int get_addr_1(inet_prefix *addr, const char *name, int family)
{
        int ret;

        ret = __get_addr_1(addr, name, family);
        if (ret)
                return ret;

        set_address_type(addr);
        return 0;
}

int af_bit_len(int af)
{
        switch (af) {
        case AF_INET6:
                return 128;
        case AF_INET:
                return 32;
        case AF_MPLS:
                return 20;
        }

        return 0;
}

static int af_byte_len(int af)
{
        return af_bit_len(af) / 8;
}

int get_prefix_1(inet_prefix *dst, char *arg, int family)
{
        char *slash;
        int err, bitlen, flags;

        slash = strchr(arg, '/');
        if (slash)
                *slash = 0;

        err = get_addr_1(dst, arg, family);

        if (slash)
                *slash = '/';

        if (err)
                return err;

        bitlen = af_bit_len(dst->family);

        flags = 0;
        if (slash) {
                unsigned int plen;

                if (dst->bitlen == -2)
                        return -1;
                if (get_netmask(&plen, slash + 1, 0))
                        return -1;
                if (plen > bitlen)
                        return -1;

                flags |= PREFIXLEN_SPECIFIED;
                bitlen = plen;
        } else {
                if (dst->bitlen == -2)
                        bitlen = 0;
        }

        dst->flags |= flags;
        dst->bitlen = bitlen;

        return 0;
}

static const char *family_name_verbose(int family)
{
        if (family == AF_UNSPEC)
                return "any valid";
        return family_name(family);
}

int get_addr(inet_prefix *dst, const char *arg, int family)
{
        if (get_addr_1(dst, arg, family)) {
                fprintf(stderr,
                        "Error: %s address is expected rather than \"%s\".\n",
                        family_name_verbose(family), arg);
                exit(1);
        }
        return 0;
}

int get_addr_rta(inet_prefix *dst, const struct rtattr *rta, int family)
{
        const int len = RTA_PAYLOAD(rta);
        const void *data = RTA_DATA(rta);

        switch (len) {
        case 4:
                dst->family = AF_INET;
                dst->bytelen = 4;
                memcpy(dst->data, data, 4);
                break;
        case 16:
                dst->family = AF_INET6;
                dst->bytelen = 16;
                memcpy(dst->data, data, 16);
                break;
        default:
                return -1;
        }

        if (family != AF_UNSPEC && family != dst->family)
                return -2;

        dst->bitlen = -1;
        dst->flags = 0;

        set_address_type(dst);
        return 0;
}

int get_prefix(inet_prefix *dst, char *arg, int family)
{
        if (family == AF_PACKET) {
                fprintf(stderr,
                        "Error: \"%s\" may be inet prefix, but it is not allowed in this context.\n",
                        arg);
                exit(1);
        }

        if (get_prefix_1(dst, arg, family)) {
                fprintf(stderr,
                        "Error: %s prefix is expected rather than \"%s\".\n",
                        family_name_verbose(family), arg);
                exit(1);
        }
        return 0;
}

__u32 get_addr32(const char *name)
{
        inet_prefix addr;

        if (get_addr_1(&addr, name, AF_INET)) {
                fprintf(stderr,
                        "Error: an IP address is expected rather than \"%s\"\n",
                        name);
                exit(1);
        }
        return addr.data[0];
}

void incomplete_command(void)
{
        fprintf(stderr, "Command line is not complete. Try option \"help\"\n");
        exit(-1);
}

void missarg(const char *key)
{
        fprintf(stderr, "Error: argument \"%s\" is required\n", key);
        exit(-1);
}

void invarg(const char *msg, const char *arg)
{
        fprintf(stderr, "Error: argument \"%s\" is wrong: %s\n", arg, msg);
        exit(-1);
}

void duparg(const char *key, const char *arg)
{
        fprintf(stderr,
                "Error: duplicate \"%s\": \"%s\" is the second value.\n",
                key, arg);
        exit(-1);
}

void duparg2(const char *key, const char *arg)
{
        fprintf(stderr,
                "Error: either \"%s\" is duplicate, or \"%s\" is a garbage.\n",
                key, arg);
        exit(-1);
}

int nodev(const char *dev)
{
        fprintf(stderr, "Cannot find device \"%s\"\n", dev);
        return -1;
}

static int __check_ifname(const char *name)
{
        if (*name == '\0')
                return -1;
        while (*name) {
                if (*name == '/' || isspace(*name))
                        return -1;
                ++name;
        }
        return 0;
}

int check_ifname(const char *name)
{
        /* These checks mimic kernel checks in dev_valid_name */
        if (strlen(name) >= IFNAMSIZ)
                return -1;
        return __check_ifname(name);
}

int check_altifname(const char *name)
{
        return __check_ifname(name);
}

/* buf is assumed to be IFNAMSIZ */
int get_ifname(char *buf, const char *name)
{
        int ret;

        ret = check_ifname(name);
        if (ret == 0)
                strncpy(buf, name, IFNAMSIZ);

        return ret;
}

const char *get_ifname_rta(int ifindex, const struct rtattr *rta)
{
        const char *name;

        if (rta) {
                name = rta_getattr_str(rta);
        } else {
                fprintf(stderr,
                        "BUG: device with ifindex %d has nil ifname\n",
                        ifindex);
                name = ll_idx_n2a(ifindex);
        }

        if (check_ifname(name))
                return NULL;

        return name;
}

/* Returns false if 'prefix' is a not empty prefix of 'string'.
 */
bool matches(const char *prefix, const char *string)
{
        if (!*prefix)
                return true;
        while (*string && *prefix == *string) {
                prefix++;
                string++;
        }

        return !!*prefix;
}

int inet_addr_match(const inet_prefix *a, const inet_prefix *b, int bits)
{
        const __u32 *a1 = a->data;
        const __u32 *a2 = b->data;
        int words = bits >> 0x05;

        bits &= 0x1f;

        if (words)
                if (memcmp(a1, a2, words << 2))
                        return -1;

        if (bits) {
                __u32 w1, w2;
                __u32 mask;

                w1 = a1[words];
                w2 = a2[words];

                mask = htonl((0xffffffff) << (0x20 - bits));

                if ((w1 ^ w2) & mask)
                        return 1;
        }

        return 0;
}

int inet_addr_match_rta(const inet_prefix *m, const struct rtattr *rta)
{
        inet_prefix dst;

        if (!rta || m->family == AF_UNSPEC || m->bitlen <= 0)
                return 0;

        if (get_addr_rta(&dst, rta, m->family))
                return -1;

        return inet_addr_match(&dst, m, m->bitlen);
}

int __iproute2_hz_internal;

int __get_hz(void)
{
        char name[1024];
        int hz = 0;
        FILE *fp;

        if (getenv("HZ"))
                return atoi(getenv("HZ")) ? : HZ;

        if (getenv("PROC_NET_PSCHED"))
                snprintf(name, sizeof(name)-1,
                         "%s", getenv("PROC_NET_PSCHED"));
        else if (getenv("PROC_ROOT"))
                snprintf(name, sizeof(name)-1,
                         "%s/net/psched", getenv("PROC_ROOT"));
        else
                strcpy(name, "/proc/net/psched");

        fp = fopen(name, "r");

        if (fp) {
                unsigned int nom, denom;

                if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2)
                        if (nom == 1000000)
                                hz = denom;
                fclose(fp);
        }
        if (hz)
                return hz;
        return HZ;
}

int __iproute2_user_hz_internal;

int __get_user_hz(void)
{
        return sysconf(_SC_CLK_TCK);
}

const char *rt_addr_n2a_r(int af, int len,
                          const void *addr, char *buf, int buflen)
{
        switch (af) {
        case AF_INET:
        case AF_INET6:
                return inet_ntop(af, addr, buf, buflen);
        case AF_MPLS:
                return mpls_ntop(af, addr, buf, buflen);
        case AF_PACKET:
                return ll_addr_n2a(addr, len, ARPHRD_VOID, buf, buflen);
        case AF_BRIDGE:
        {
                const union {
                        struct sockaddr sa;
                        struct sockaddr_in sin;
                        struct sockaddr_in6 sin6;
                } *sa = addr;

                switch (sa->sa.sa_family) {
                case AF_INET:
                        return inet_ntop(AF_INET, &sa->sin.sin_addr,
                                         buf, buflen);
                case AF_INET6:
                        return inet_ntop(AF_INET6, &sa->sin6.sin6_addr,
                                         buf, buflen);
                }

                /* fallthrough */
        }
        default:
                return "???";
        }
}

const char *rt_addr_n2a(int af, int len, const void *addr)
{
        static char buf[256];

        return rt_addr_n2a_r(af, len, addr, buf, 256);
}

int read_family(const char *name)
{
        int family = AF_UNSPEC;

        if (strcmp(name, "inet") == 0)
                family = AF_INET;
        else if (strcmp(name, "inet6") == 0)
                family = AF_INET6;
        else if (strcmp(name, "link") == 0)
                family = AF_PACKET;
        else if (strcmp(name, "mpls") == 0)
                family = AF_MPLS;
        else if (strcmp(name, "bridge") == 0)
                family = AF_BRIDGE;
        return family;
}

const char *family_name(int family)
{
        if (family == AF_INET)
                return "inet";
        if (family == AF_INET6)
                return "inet6";
        if (family == AF_PACKET)
                return "link";
        if (family == AF_MPLS)
                return "mpls";
        if (family == AF_BRIDGE)
                return "bridge";
        return "???";
}

#ifdef RESOLVE_HOSTNAMES
struct namerec {
        struct namerec *next;
        const char *name;
        inet_prefix addr;
};

#define NHASH 257
static struct namerec *nht[NHASH];

static const char *resolve_address(const void *addr, int len, int af)
{
        struct namerec *n;
        struct hostent *h_ent;
        unsigned int hash;
        static int notfirst;


        if (af == AF_INET6 && ((__u32 *)addr)[0] == 0 &&
            ((__u32 *)addr)[1] == 0 && ((__u32 *)addr)[2] == htonl(0xffff)) {
                af = AF_INET;
                addr += 12;
                len = 4;
        }

        hash = *(__u32 *)(addr + len - 4) % NHASH;

        for (n = nht[hash]; n; n = n->next) {
                if (n->addr.family == af &&
                    n->addr.bytelen == len &&
                    memcmp(n->addr.data, addr, len) == 0)
                        return n->name;
        }
        n = malloc(sizeof(*n));
        if (n == NULL)
                return NULL;
        n->addr.family = af;
        n->addr.bytelen = len;
        n->name = NULL;
        memcpy(n->addr.data, addr, len);
        n->next = nht[hash];
        nht[hash] = n;
        if (++notfirst == 1)
                sethostent(1);
        fflush(stdout);

        h_ent = gethostbyaddr(addr, len, af);
        if (h_ent != NULL)
                n->name = strdup(h_ent->h_name);

        /* Even if we fail, "negative" entry is remembered. */
        return n->name;
}
#endif

const char *format_host_r(int af, int len, const void *addr,
                        char *buf, int buflen)
{
#ifdef RESOLVE_HOSTNAMES
        if (resolve_hosts) {
                const char *n;

                len = len <= 0 ? af_byte_len(af) : len;

                if (len > 0 &&
                    (n = resolve_address(addr, len, af)) != NULL)
                        return n;
        }
#endif
        return rt_addr_n2a_r(af, len, addr, buf, buflen);
}

const char *format_host(int af, int len, const void *addr)
{
        static char buf[256];

        return format_host_r(af, len, addr, buf, 256);
}


char *hexstring_n2a(const __u8 *str, int len, char *buf, int blen)
{
        char *ptr = buf;
        int i;

        for (i = 0; i < len; i++) {
                if (blen < 3)
                        break;
                sprintf(ptr, "%02x", str[i]);
                ptr += 2;
                blen -= 2;
        }
        return buf;
}

__u8 *hexstring_a2n(const char *str, __u8 *buf, int blen, unsigned int *len)
{
        unsigned int cnt = 0;
        char *endptr;

        if (strlen(str) % 2)
                return NULL;
        while (cnt < blen && strlen(str) > 1) {
                unsigned int tmp;
                char tmpstr[3];

                strncpy(tmpstr, str, 2);
                tmpstr[2] = '\0';
                errno = 0;
                tmp = strtoul(tmpstr, &endptr, 16);
                if (errno != 0 || tmp > 0xFF || *endptr != '\0')
                        return NULL;
                buf[cnt++] = tmp;
                str += 2;
        }

        if (len)
                *len = cnt;

        return buf;
}

int hex2mem(const char *buf, uint8_t *mem, int count)
{
        int i, j;
        int c;

        for (i = 0, j = 0; i < count; i++, j += 2) {
                c = get_hex(buf[j]);
                if (c < 0)
                        return -1;

                mem[i] = c << 4;

                c = get_hex(buf[j + 1]);
                if (c < 0)
                        return -1;

                mem[i] |= c;
        }

        return 0;
}

int addr64_n2a(__u64 addr, char *buff, size_t len)
{
        __u16 *words = (__u16 *)&addr;
        __u16 v;
        int i, ret;
        size_t written = 0;
        char *sep = ":";

        for (i = 0; i < 4; i++) {
                v = ntohs(words[i]);

                if (i == 3)
                        sep = "";

                ret = snprintf(&buff[written], len - written, "%x%s", v, sep);
                if (ret < 0)
                        return ret;

                written += ret;
        }

        return written;
}

/* Print buffer and escape bytes that are !isprint or among 'escape' */
void print_escape_buf(const __u8 *buf, size_t len, const char *escape)
{
        size_t i;

        for (i = 0; i < len; ++i) {
                if (isprint(buf[i]) && buf[i] != '\\' &&
                    !strchr(escape, buf[i]))
                        printf("%c", buf[i]);
                else
                        printf("\\%03o", buf[i]);
        }
}

int print_timestamp(FILE *fp)
{
        struct timeval tv;
        struct tm *tm;

        gettimeofday(&tv, NULL);
        tm = localtime(&tv.tv_sec);

        if (timestamp_short) {
                char tshort[40];

                strftime(tshort, sizeof(tshort), "%Y-%m-%dT%H:%M:%S", tm);
                fprintf(fp, "[%s.%06ld] ", tshort, tv.tv_usec);
        } else {
                char *tstr = asctime(tm);

                tstr[strlen(tstr)-1] = 0;
                fprintf(fp, "Timestamp: %s %ld usec\n",
                        tstr, tv.tv_usec);
        }

        return 0;
}

unsigned int print_name_and_link(const char *fmt,
                                 const char *name, struct rtattr *tb[])
{
        const char *link = NULL;
        unsigned int m_flag = 0;
        SPRINT_BUF(b1);

        if (tb[IFLA_LINK]) {
                int iflink = rta_getattr_u32(tb[IFLA_LINK]);

                if (iflink) {
                        if (tb[IFLA_LINK_NETNSID]) {
                                if (is_json_context()) {
                                        print_int(PRINT_JSON,
                                                  "link_index", NULL, iflink);
                                } else {
                                        link = ll_idx_n2a(iflink);
                                }
                        } else {
                                link = ll_index_to_name(iflink);

                                if (is_json_context()) {
                                        print_string(PRINT_JSON,
                                                     "link", NULL, link);
                                        link = NULL;
                                }

                                m_flag = ll_index_to_flags(iflink);
                                m_flag = !(m_flag & IFF_UP);
                        }
                } else {
                        if (is_json_context())
                                print_null(PRINT_JSON, "link", NULL, NULL);
                        else
                                link = "NONE";
                }

                if (link) {
                        snprintf(b1, sizeof(b1), "%s@%s", name, link);
                        name = b1;
                }
        }

        print_color_string(PRINT_ANY, COLOR_IFNAME, "ifname", fmt, name);

        return m_flag;
}

int cmdlineno;

/* Like glibc getline but handle continuation lines and comments */
ssize_t getcmdline(char **linep, size_t *lenp, FILE *in)
{
        ssize_t cc;
        char *cp;

        cc = getline(linep, lenp, in);
        if (cc < 0)
                return cc;      /* eof or error */
        ++cmdlineno;

        cp = strchr(*linep, '#');
        if (cp)
                *cp = '\0';

        while ((cp = strstr(*linep, "\\\n")) != NULL) {
                char *line1 = NULL;
                size_t len1 = 0;
                ssize_t cc1;

                cc1 = getline(&line1, &len1, in);
                if (cc1 < 0) {
                        fprintf(stderr, "Missing continuation line\n");
                        return cc1;
                }

                ++cmdlineno;
                *cp = 0;

                cp = strchr(line1, '#');
                if (cp)
                        *cp = '\0';

                *lenp = strlen(*linep) + strlen(line1) + 1;
                *linep = realloc(*linep, *lenp);
                if (!*linep) {
                        fprintf(stderr, "Out of memory\n");
                        *lenp = 0;
                        return -1;
                }
                cc += cc1 - 2;
                strcat(*linep, line1);
                free(line1);
        }
        return cc;
}

/* split command line into argument vector */
int makeargs(char *line, char *argv[], int maxargs)
{
        static const char ws[] = " \t\r\n";
        char *cp = line;
        int argc = 0;

        while (*cp) {
                /* skip leading whitespace */
                cp += strspn(cp, ws);

                if (*cp == '\0')
                        break;

                if (argc >= (maxargs - 1)) {
                        fprintf(stderr, "Too many arguments to command\n");
                        exit(1);
                }

                /* word begins with quote */
                if (*cp == '\'' || *cp == '"') {
                        char quote = *cp++;

                        argv[argc++] = cp;
                        /* find ending quote */
                        cp = strchr(cp, quote);
                        if (cp == NULL) {
                                fprintf(stderr, "Unterminated quoted string\n");
                                exit(1);
                        }
                } else {
                        argv[argc++] = cp;

                        /* find end of word */
                        cp += strcspn(cp, ws);
                        if (*cp == '\0')
                                break;
                }

                /* separate words */
                *cp++ = 0;
        }
        argv[argc] = NULL;

        return argc;
}

void print_nlmsg_timestamp(FILE *fp, const struct nlmsghdr *n)
{
        char *tstr;
        time_t secs = ((__u32 *)NLMSG_DATA(n))[0];
        long usecs = ((__u32 *)NLMSG_DATA(n))[1];

        tstr = asctime(localtime(&secs));
        tstr[strlen(tstr)-1] = 0;
        fprintf(fp, "Timestamp: %s %lu us\n", tstr, usecs);
}

char *int_to_str(int val, char *buf)
{
        sprintf(buf, "%d", val);
        return buf;
}

int get_guid(__u64 *guid, const char *arg)
{
        unsigned long tmp;
        char *endptr;
        int i;

#define GUID_STR_LEN 23
        /* Verify strict format: format string must be
         * xx:xx:xx:xx:xx:xx:xx:xx where xx can be an arbitrary
         * hex digit
         */

        if (strlen(arg) != GUID_STR_LEN)
                return -1;

        /* make sure columns are in place */
        for (i = 0; i < 7; i++)
                if (arg[2 + i * 3] != ':')
                        return -1;

        *guid = 0;
        for (i = 0; i < 8; i++) {
                tmp = strtoul(arg + i * 3, &endptr, 16);
                if (endptr != arg + i * 3 + 2)
                        return -1;

                if (tmp > 255)
                        return -1;

                *guid |= tmp << (56 - 8 * i);
        }

        return 0;
}

/* This is a necessary workaround for multicast route dumps */
int get_real_family(int rtm_type, int rtm_family)
{
        if (rtm_type != RTN_MULTICAST)
                return rtm_family;

        if (rtm_family == RTNL_FAMILY_IPMR)
                return AF_INET;

        if (rtm_family == RTNL_FAMILY_IP6MR)
                return AF_INET6;

        return rtm_family;
}

/* Based on copy_rtnl_link_stats() from kernel at net/core/rtnetlink.c */
static void copy_rtnl_link_stats64(struct rtnl_link_stats64 *stats64,
                                   const struct rtnl_link_stats *stats)
{
        __u64 *a = (__u64 *)stats64;
        const __u32 *b = (const __u32 *)stats;
        const __u32 *e = b + sizeof(*stats) / sizeof(*b);

        while (b < e)
                *a++ = *b++;
}

#define IPSTATS_MIB_MAX_LEN     (__IPSTATS_MIB_MAX * sizeof(__u64))
static void get_snmp_counters(struct rtnl_link_stats64 *stats64,
                              struct rtattr *s)
{
        __u64 *mib = (__u64 *)RTA_DATA(s);

        memset(stats64, 0, sizeof(*stats64));

        stats64->rx_packets = mib[IPSTATS_MIB_INPKTS];
        stats64->rx_bytes = mib[IPSTATS_MIB_INOCTETS];
        stats64->tx_packets = mib[IPSTATS_MIB_OUTPKTS];
        stats64->tx_bytes = mib[IPSTATS_MIB_OUTOCTETS];
        stats64->rx_errors = mib[IPSTATS_MIB_INDISCARDS];
        stats64->tx_errors = mib[IPSTATS_MIB_OUTDISCARDS];
        stats64->multicast = mib[IPSTATS_MIB_INMCASTPKTS];
        stats64->rx_frame_errors = mib[IPSTATS_MIB_CSUMERRORS];
}

int get_rtnl_link_stats_rta(struct rtnl_link_stats64 *stats64,
                            struct rtattr *tb[])
{
        struct rtnl_link_stats stats;
        void *s;
        struct rtattr *rta;
        int size, len;

        if (tb[IFLA_STATS64]) {
                rta = tb[IFLA_STATS64];
                size = sizeof(struct rtnl_link_stats64);
                s = stats64;
        } else if (tb[IFLA_STATS]) {
                rta = tb[IFLA_STATS];
                size = sizeof(struct rtnl_link_stats);
                s = &stats;
        } else if (tb[IFLA_PROTINFO]) {
                struct rtattr *ptb[IPSTATS_MIB_MAX_LEN + 1];

                parse_rtattr_nested(ptb, IPSTATS_MIB_MAX_LEN,
                                    tb[IFLA_PROTINFO]);
                if (ptb[IFLA_INET6_STATS])
                        get_snmp_counters(stats64, ptb[IFLA_INET6_STATS]);
                return sizeof(*stats64);
        } else {
                return -1;
        }

        len = RTA_PAYLOAD(rta);
        if (len < size)
                memset(s + len, 0, size - len);
        else
                len = size;

        memcpy(s, RTA_DATA(rta), len);

        if (s != stats64)
                copy_rtnl_link_stats64(stats64, s);
        return size;
}

#ifdef NEED_STRLCPY
size_t strlcpy(char *dst, const char *src, size_t size)
{
        size_t srclen = strlen(src);

        if (size) {
                size_t minlen = min(srclen, size - 1);

                memcpy(dst, src, minlen);
                dst[minlen] = '\0';
        }
        return srclen;
}

size_t strlcat(char *dst, const char *src, size_t size)
{
        size_t dlen = strlen(dst);

        if (dlen >= size)
                return dlen + strlen(src);

        return dlen + strlcpy(dst + dlen, src, size - dlen);
}
#endif

void drop_cap(void)
{
#ifdef HAVE_LIBCAP
        /* don't harmstring root/sudo */
        if (getuid() != 0 && geteuid() != 0) {
                cap_t capabilities;
                cap_value_t net_admin = CAP_NET_ADMIN;
                cap_flag_t inheritable = CAP_INHERITABLE;
                cap_flag_value_t is_set;

                capabilities = cap_get_proc();
                if (!capabilities)
                        exit(EXIT_FAILURE);
                if (cap_get_flag(capabilities, net_admin, inheritable,
                    &is_set) != 0)
                        exit(EXIT_FAILURE);
                /* apps with ambient caps can fork and call ip */
                if (is_set == CAP_CLEAR) {
                        if (cap_clear(capabilities) != 0)
                                exit(EXIT_FAILURE);
                        if (cap_set_proc(capabilities) != 0)
                                exit(EXIT_FAILURE);
                }
                cap_free(capabilities);
        }
#endif
}

int get_time(unsigned int *time, const char *str)
{
        double t;
        char *p;

        t = strtod(str, &p);
        if (p == str)
                return -1;

        if (*p) {
                if (strcasecmp(p, "s") == 0 || strcasecmp(p, "sec") == 0 ||
                    strcasecmp(p, "secs") == 0)
                        t *= TIME_UNITS_PER_SEC;
                else if (strcasecmp(p, "ms") == 0 || strcasecmp(p, "msec") == 0 ||
                         strcasecmp(p, "msecs") == 0)
                        t *= TIME_UNITS_PER_SEC/1000;
                else if (strcasecmp(p, "us") == 0 || strcasecmp(p, "usec") == 0 ||
                         strcasecmp(p, "usecs") == 0)
                        t *= TIME_UNITS_PER_SEC/1000000;
                else
                        return -1;
        }

        *time = t;
        return 0;
}

static void print_time(char *buf, int len, __u32 time)
{
        double tmp = time;

        if (tmp >= TIME_UNITS_PER_SEC)
                snprintf(buf, len, "%.3gs", tmp/TIME_UNITS_PER_SEC);
        else if (tmp >= TIME_UNITS_PER_SEC/1000)
                snprintf(buf, len, "%.3gms", tmp/(TIME_UNITS_PER_SEC/1000));
        else
                snprintf(buf, len, "%uus", time);
}

char *sprint_time(__u32 time, char *buf)
{
        print_time(buf, SPRINT_BSIZE-1, time);
        return buf;
}

/* 64 bit times are represented internally in nanoseconds */
int get_time64(__s64 *time, const char *str)
{
        double nsec;
        char *p;

        nsec = strtod(str, &p);
        if (p == str)
                return -1;

        if (*p) {
                if (strcasecmp(p, "s") == 0 ||
                    strcasecmp(p, "sec") == 0 ||
                    strcasecmp(p, "secs") == 0)
                        nsec *= NSEC_PER_SEC;
                else if (strcasecmp(p, "ms") == 0 ||
                         strcasecmp(p, "msec") == 0 ||
                         strcasecmp(p, "msecs") == 0)
                        nsec *= NSEC_PER_MSEC;
                else if (strcasecmp(p, "us") == 0 ||
                         strcasecmp(p, "usec") == 0 ||
                         strcasecmp(p, "usecs") == 0)
                        nsec *= NSEC_PER_USEC;
                else if (strcasecmp(p, "ns") == 0 ||
                         strcasecmp(p, "nsec") == 0 ||
                         strcasecmp(p, "nsecs") == 0)
                        nsec *= 1;
                else
                        return -1;
        }

        *time = nsec;
        return 0;
}

static void print_time64(char *buf, int len, __s64 time)
{
        double nsec = time;

        if (time >= NSEC_PER_SEC)
                snprintf(buf, len, "%.3gs", nsec/NSEC_PER_SEC);
        else if (time >= NSEC_PER_MSEC)
                snprintf(buf, len, "%.3gms", nsec/NSEC_PER_MSEC);
        else if (time >= NSEC_PER_USEC)
                snprintf(buf, len, "%.3gus", nsec/NSEC_PER_USEC);
        else
                snprintf(buf, len, "%lldns", time);
}

char *sprint_time64(__s64 time, char *buf)
{
        print_time64(buf, SPRINT_BSIZE-1, time);
        return buf;
}

int do_batch(const char *name, bool force,
             int (*cmd)(int argc, char *argv[], void *data), void *data)
{
        char *line = NULL;
        size_t len = 0;
        int ret = EXIT_SUCCESS;

        if (name && strcmp(name, "-") != 0) {
                if (freopen(name, "r", stdin) == NULL) {
                        fprintf(stderr,
                                "Cannot open file \"%s\" for reading: %s\n",
                                name, strerror(errno));
                        return EXIT_FAILURE;
                }
        }

        cmdlineno = 0;
        while (getcmdline(&line, &len, stdin) != -1) {
                char *largv[MAX_ARGS];
                int largc;

                largc = makeargs(line, largv, MAX_ARGS);
                if (!largc)
                        continue;       /* blank line */

                if (cmd(largc, largv, data)) {
                        fprintf(stderr, "Command failed %s:%d\n",
                                name, cmdlineno);
                        ret = EXIT_FAILURE;
                        if (!force)
                                break;
                }
        }

        if (line)
                free(line);

        return ret;
}

int parse_one_of(const char *msg, const char *realval, const char * const *list,
                 size_t len, int *p_err)
{
        int i;

        for (i = 0; i < len; i++) {
                if (list[i] && matches(realval, list[i]) == 0) {
                        *p_err = 0;
                        return i;
                }
        }

        fprintf(stderr, "Error: argument of \"%s\" must be one of ", msg);
        for (i = 0; i < len; i++)
                if (list[i])
                        fprintf(stderr, "\"%s\", ", list[i]);
        fprintf(stderr, "not \"%s\"\n", realval);
        *p_err = -EINVAL;
        return 0;
}

bool parse_on_off(const char *msg, const char *realval, int *p_err)
{
        static const char * const values_on_off[] = { "off", "on" };

        return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
}

int parse_mapping_gen(int *argcp, char ***argvp,
                      int (*key_cb)(__u32 *keyp, const char *key),
                      int (*mapping_cb)(__u32 key, char *value, void *data),
                      void *mapping_cb_data)
{
        int argc = *argcp;
        char **argv = *argvp;
        int ret = 0;

        while (argc > 0) {
                char *colon = strchr(*argv, ':');
                __u32 key;

                if (!colon)
                        break;
                *colon = '\0';

                if (key_cb(&key, *argv)) {
                        ret = 1;
                        break;
                }
                if (mapping_cb(key, colon + 1, mapping_cb_data)) {
                        ret = 1;
                        break;
                }

                argc--, argv++;
        }

        *argcp = argc;
        *argvp = argv;
        return ret;
}

static int parse_mapping_num(__u32 *keyp, const char *key)
{
        return get_u32(keyp, key, 0);
}

int parse_mapping_num_all(__u32 *keyp, const char *key)
{
        if (matches(key, "all") == 0) {
                *keyp = (__u32) -1;
                return 0;
        }
        return parse_mapping_num(keyp, key);
}

int parse_mapping(int *argcp, char ***argvp, bool allow_all,
                  int (*mapping_cb)(__u32 key, char *value, void *data),
                  void *mapping_cb_data)
{
        if (allow_all)
                return parse_mapping_gen(argcp, argvp, parse_mapping_num_all,
                                         mapping_cb, mapping_cb_data);
        else
                return parse_mapping_gen(argcp, argvp, parse_mapping_num,
                                         mapping_cb, mapping_cb_data);
}

int str_map_lookup_str(const struct str_num_map *map, const char *needle)
{
        if (!needle)
                return -EINVAL;

        /* Process array which is NULL terminated by the string. */
        while (map && map->str) {
                if (strcmp(map->str, needle) == 0)
                        return map->num;

                map++;
        }
        return -EINVAL;
}

const char *str_map_lookup_uint(const struct str_num_map *map, unsigned int val)
{
        unsigned int num = val;

        while (map && map->str) {
                if (num == map->num)
                        return map->str;

                map++;
        }
        return NULL;
}

const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val)
{
        unsigned int num = val;

        while (map && map->str) {
                if (num == map->num)
                        return map->str;

                map++;
        }
        return NULL;
}

const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val)
{
        unsigned int num = val;

        while (map && map->str) {
                if (num == map->num)
                        return map->str;

                map++;
        }
        return NULL;
}

unsigned int get_str_char_count(const char *str, int match)
{
        unsigned int count = 0;
        const char *pos = str;

        while ((pos = strchr(pos, match))) {
                count++;
                pos++;
        }
        return count;
}

int str_split_by_char(char *str, char **before, char **after, int match)
{
        char *slash;

        slash = strrchr(str, match);
        if (!slash)
                return -EINVAL;
        *slash = '\0';
        *before = str;
        *after = slash + 1;
        return 0;
}

struct indent_mem *alloc_indent_mem(void)
{
        struct indent_mem *mem = malloc(sizeof(*mem));

        if (!mem)
                return NULL;
        strcpy(mem->indent_str, "");
        mem->indent_level = 0;
        return mem;
}

void free_indent_mem(struct indent_mem *mem)
{
        free(mem);
}

#define INDENT_STR_STEP 2

void inc_indent(struct indent_mem *mem)
{
        if (mem->indent_level + INDENT_STR_STEP > INDENT_STR_MAXLEN)
                return;
        mem->indent_level += INDENT_STR_STEP;
        memset(mem->indent_str, ' ', sizeof(mem->indent_str));
        mem->indent_str[mem->indent_level] = '\0';
}

void dec_indent(struct indent_mem *mem)
{
        if (mem->indent_level - INDENT_STR_STEP < 0)
                return;
        mem->indent_level -= INDENT_STR_STEP;
        mem->indent_str[mem->indent_level] = '\0';
}

void print_indent(struct indent_mem *mem)
{
        if (mem->indent_level)
                printf("%s", mem->indent_str);
}