ip.c

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/* -*- C -*- */
/*
 * Copyright (c) 2021 Seagate Technology LLC and/or its Affiliates
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * For any questions about this software or licensing,
 * please email opensource@seagate.com or cortx-questions@seagate.com.
 *
 */

#define M0_TRACE_SUBSYSTEM M0_TRACE_SUBSYS_NET
#include "lib/trace.h"

#ifndef __KERNEL__

#include "net/net_internal.h"
#include "lib/assert.h"
#include "lib/errno.h"
#include "lib/string.h"
#include <arpa/inet.h>          /* inet_pton, htons */
#include <netdb.h>              /* hostent */
#include <stdlib.h>             /* atoi */

static const char *ip_family[M0_NET_IP_AF_NR] = {
                                                [M0_NET_IP_AF_INET]  = "inet",
                                                [M0_NET_IP_AF_INET6] = "inet6",
                                                [M0_NET_IP_AF_UNIX]  = "unix" };

static const char *ip_protocol[M0_NET_IP_PROTO_NR] = {
                                            [M0_NET_IP_PROTO_TCP]    = "tcp",
                                            [M0_NET_IP_PROTO_UDP]    = "udp",
                                            [M0_NET_IP_PROTO_VERBS]  = "verbs",
                                            [M0_NET_IP_PROTO_O2IB]   = "o2ib" };

/* This is the max strlen of members of ip_family and ip_protocol */
#define MAX_PREFIX_STRLEN    10

static uint8_t ip_autotm[1024] = {};

enum { IP_AUTOTM_NR = ARRAY_SIZE(ip_autotm) };

static struct m0_mutex autotm_lock = {};

static int m0_net_ip_to_hostname(const char *ip, char *hostname)
{
        struct hostent *he;
        struct in_addr  addr;
        int             rc;

        inet_aton(ip, &addr);
        he = gethostbyaddr(&addr, sizeof(addr), AF_INET);
        if (he == NULL) {
                M0_LOG(M0_ERROR, "gethostbyaddr err=%d for %s",
                       h_errno, (char*)ip);
                /* Return error code for gethostbyaddr failure */
                return M0_ERR(-h_errno);
        }
        M0_LOG(M0_DEBUG, "ip: %s to hostname: %s\n",ip, he->h_name);
        rc = snprintf(hostname, M0_NET_IP_STRLEN_MAX, "%s", he->h_name);

        if (rc <= 0 || rc >= M0_NET_IP_STRLEN_MAX)
                return M0_ERR(-EINVAL);

        return M0_RC(0);
}


static int parse_prefix(const char *ep_name, const char **prefixes,
                         int nr_prefixes, int *index, int *shift)
{
        int i;

        for (i = 0; i < nr_prefixes; ++i) {
                if (prefixes[i] != NULL) {
                        *shift = strnlen(prefixes[i], MAX_PREFIX_STRLEN);
                        if (strncmp(ep_name, prefixes[i], *shift) == 0) {
                                *index = i;
                                break;
                        }
                }
        }

        if (i >= nr_prefixes)
                return M0_ERR(-EINVAL);

        return 0;

}

static int m0_net_ip_inet_parse(const char *name, struct m0_net_ip_addr *addr)
{
        long int     portnum;
        int          shift = 0;
        int          family = 0;
        int          type = 0;
        int          rc;
        char         ip[M0_NET_IP_STRLEN_MAX] = {};
        char         port[M0_NET_IP_PORTLEN_MAX] = {};
        char        *at;
        const char  *ep_name = name;
        char        *end;

        rc = parse_prefix(ep_name, ip_family, ARRAY_SIZE(ip_family), &family,
                          &shift);
        if (rc != 0 || ep_name[shift] != ':')
                return M0_ERR(-EINVAL);
        ep_name += shift + 1;

        rc = parse_prefix(ep_name, ip_protocol, ARRAY_SIZE(ip_protocol), &type,
                     &shift);
        if (rc != 0 || ep_name[shift] != ':')
                return M0_ERR(-EINVAL);
        ep_name += shift + 1;

        at = strchr(ep_name, '@');
        if (at == NULL)
                return M0_ERR(-EINVAL);
        else {
                at++;
                if (at == NULL || !isdigit(at[0]))
                        return M0_ERR(-EINVAL);
                strcpy(port, at);
                portnum = strtol(port, &end, 10);
                if (portnum > M0_NET_IP_PORT_MAX)
                        return M0_ERR(-EINVAL);
                addr->nia_n.nip_port = (uint16_t)portnum;
        }

        rc = m0_net_hostname_to_ip((char *)ep_name, ip,
                                   &addr->nia_n.nip_format);
        if (rc == 0)
                inet_pton(family == M0_NET_IP_AF_INET ? AF_INET : AF_INET6,
                          ip, &addr->nia_n.nip_ip_n.sn[0]);

        /*
         * To fix codacy warning for strlen, check only if the strnlen exceeds
         * the array size of addr->nia_p.
         */
        M0_ASSERT(strnlen(name, ARRAY_SIZE(addr->nia_p) + 1 ) <
                  ARRAY_SIZE(addr->nia_p));
        strcpy(addr->nia_p, name);
        addr->nia_n.nip_fmt_pvt.ia.nia_family = family;
        addr->nia_n.nip_fmt_pvt.ia.nia_type = type;

        /* Ignore the error due to gethostbyname() as it will be retried. */
        return rc >= 0 ? M0_RC(0) : M0_ERR(rc);
}

static int m0_net_ip_lnet_parse(const char *name, struct m0_net_ip_addr *addr)
{
        char            *at = NULL;
        int              nr;
        int              i;
        int              pid;
        int              portal;
        int              portnum;
        int              tmid;
        char             node[M0_NET_IP_STRLEN_MAX] = {};
        char             port[M0_NET_IP_PORTLEN_MAX] = {};
        const char      *ep_name = name;
        uint32_t         nia_n;
        int              shift;
        int              type = 0;
        int              rc;
        bool             is_localhost = false;


        at = strchr(ep_name, '@');
        if (strncmp(ep_name, "0@lo", 4) == 0) {
                nia_n = htonl(INADDR_LOOPBACK);
                inet_ntop(AF_INET, &nia_n, node, ARRAY_SIZE(node));
                is_localhost = true;
        } else {
                if (at == NULL || at - ep_name >= sizeof node)
                        return M0_ERR(-EPROTO);

                M0_PRE(sizeof node >= (at-ep_name)+1);
                memcpy(node, ep_name, at - ep_name);
                at++;
                rc = parse_prefix(at, ip_protocol, ARRAY_SIZE(ip_protocol),
                                  &type, &shift);
                if (rc != 0)
                        return M0_ERR(rc);
        }

        if (at == NULL || (at = strchr(at, ':')) == NULL)
                return M0_ERR(-EPROTO);

        nr = sscanf(at + 1, "%d:%d:%d", &pid, &portal, &tmid);
        if (nr != 3) {
                nr = sscanf(at + 1, "%d:%d:*", &pid, &portal);
                if (nr != 2)
                        return M0_ERR(-EPROTO);
                m0_mutex_lock(&autotm_lock);
                for (i = 0; i < IP_AUTOTM_NR; ++i) {
                        /*
                         * Start assigning auto-tm indices from the middle of
                         * the bitmap to avoid clashes within UT-s.
                         */
                        int probe = (i + IP_AUTOTM_NR / 2) % IP_AUTOTM_NR;
                        if (ip_autotm[probe] == 0) {
                                tmid = probe;
                                /* To handle '*' wildchar as tmid*/
                                addr->nia_n.nip_fmt_pvt.la.nla_autotm = true;
                                ip_autotm[tmid] = 1;
                                break;
                        }
                }
                m0_mutex_unlock(&autotm_lock);
                if (i == ARRAY_SIZE(ip_autotm))
                        return M0_ERR(-EADDRNOTAVAIL);
        } else
                addr->nia_n.nip_fmt_pvt.la.nla_autotm = false;

        if (pid != 12345)
                return M0_ERR(-EPROTO);
        /*
        * Deterministically combine portal and tmid into a unique 16-bit port
        * number (greater than 1024). Tricky.
        *
        * Port number is, in binary: tttttttttt1ppppp, that is, 10 bits of tmid
        * (which must be less than 1024), followed by a set bit (guaranteeing
        * that the port is not reserved), followed by 5 bits of (portal - 30),
        * so that portal must be in the range 30..61.
        *
        if (tmid >= 1024 || (portal - 30) >= 32)
                return M0_ERR_INFO(-EPROTO,
                        "portal: %u, tmid: %u", portal, tmid);
        */

        addr->nia_n.nip_fmt_pvt.la.nla_portal =  (uint16_t)portal;
        if (portal < 30)
                portal = 30 + portal;

        portnum  = tmid | (1 << 10) | ((portal - 30) << 11);
        if (portnum > M0_NET_IP_PORT_MAX)
                return M0_ERR(-EINVAL);
        snprintf(port, ARRAY_SIZE(port), "%d", (uint32_t)portnum);
        addr->nia_n.nip_format = M0_NET_IP_LNET_FORMAT;
        inet_pton(AF_INET, node, &addr->nia_n.nip_ip_n.sn[0]);
        addr->nia_n.nip_fmt_pvt.la.nla_tmid = (uint16_t)tmid;
        addr->nia_n.nip_port = (uint16_t)portnum;
        addr->nia_n.nip_fmt_pvt.la.nla_type = is_localhost ? 0xFF : type;
        /*
         * To fix codacy warning for strlen, check only if the strnlen exceeds
         * the array size of addr->nia_p.
         */
        M0_ASSERT(strnlen(name, ARRAY_SIZE(addr->nia_p) + 1 ) <
                  ARRAY_SIZE(addr->nia_p));
        strcpy(addr->nia_p, name);

        return M0_RC(0);
}

static bool m0_net_ip_v4_eq(const uint32_t *a1, const uint32_t *a2)
{
        return (a1[0] == a2[0]);
}

static bool m0_net_ip_v6_eq(const uint64_t *a1, const uint64_t *a2)
{
        return (a1[0] == a2[0] && a1[1] == a2[1]);
}

static bool m0_net_ip_la_eq(const struct m0_net_ip_addr *a1,
                            const struct m0_net_ip_addr *a2)
{
        const struct m0_net_ip_lnet_addr *la1 = &a1->nia_n.nip_fmt_pvt.la;
        const struct m0_net_ip_lnet_addr *la2 = &a2->nia_n.nip_fmt_pvt.la;

        M0_PRE(a1 != NULL && a2 != NULL);

        return (la1->nla_type   == la2->nla_type   &&
                la1->nla_portal == la2->nla_portal &&
                la1->nla_tmid   == la2->nla_tmid   &&
                la1->nla_autotm == la2->nla_autotm &&
                m0_net_ip_v4_eq(&a1->nia_n.nip_ip_n.sn[0],
                                &a2->nia_n.nip_ip_n.sn[0]));
}

static bool m0_net_ip_ia_eq(const struct m0_net_ip_addr *a1,
                            const struct m0_net_ip_addr *a2)
{
        const struct m0_net_ip_inet_addr *ia1 = &a1->nia_n.nip_fmt_pvt.ia;
        const struct m0_net_ip_inet_addr *ia2 = &a2->nia_n.nip_fmt_pvt.ia;

        M0_PRE(a1 != NULL && a2 != NULL);

        return (ia1->nia_family == ia2->nia_family &&
                ia1->nia_type   == ia2->nia_type &&
                ia1->nia_family == M0_NET_IP_AF_INET ?
                m0_net_ip_v4_eq(&a1->nia_n.nip_ip_n.sn[0],
                                &a2->nia_n.nip_ip_n.sn[0]) :
                m0_net_ip_v6_eq(&a1->nia_n.nip_ip_n.ln[0],
                                &a2->nia_n.nip_ip_n.ln[0]));
}

M0_INTERNAL int m0_net_ip_parse(const char *name, struct m0_net_ip_addr *addr)
{
        return isdigit(name[0]) ? m0_net_ip_lnet_parse(name, addr) :
               m0_net_ip_inet_parse(name, addr);
}

M0_INTERNAL int m0_net_ip_print(const struct m0_net_ip_addr *nia)
{
        char  ip_p[INET6_ADDRSTRLEN] = {};
        char  hostname[M0_NET_IP_STRLEN_MAX] = {};
        char  tmid[6] = {};
        char *buf = (char *)nia->nia_p;
        const struct m0_net_ip_params *na = &nia->nia_n;
        int   rc = 0;

        M0_ENTRY("frmt=%d nip_ip_n=[0x%" PRIx64 ",0x%" PRIx64 "] port=%d",
                 (int)na->nip_format, na->nip_ip_n.ln[0], na->nip_ip_n.ln[1],
                 (int)na->nip_port);

        if (na->nip_format == M0_NET_IP_LNET_FORMAT)
                M0_LOG(M0_DEBUG, "type=%d portal=%d tmid=%d autotm=%s",
                       (int)na->nip_fmt_pvt.la.nla_type,
                       (int)na->nip_fmt_pvt.la.nla_portal,
                       (int)na->nip_fmt_pvt.la.nla_tmid,
                       na->nip_fmt_pvt.la.nla_autotm ? "true" : "false");
        else
                M0_LOG(M0_DEBUG, "family=%d type=%d",
                       (int)na->nip_fmt_pvt.ia.nia_family,
                       (int)na->nip_fmt_pvt.ia.nia_type);

        if (na->nip_format == M0_NET_IP_LNET_FORMAT) {
                rc = na->nip_fmt_pvt.la.nla_autotm ?
                     snprintf(tmid, ARRAY_SIZE(tmid), "*") :
                     snprintf(tmid, ARRAY_SIZE(tmid), "%d",
                              na->nip_fmt_pvt.la.nla_tmid);
                M0_ASSERT(rc < ARRAY_SIZE(tmid));
                inet_ntop(AF_INET, &na->nip_ip_n.sn[0], ip_p, ARRAY_SIZE(ip_p));
                rc = snprintf(buf, M0_NET_IP_STRLEN_MAX,
                              "%s@%s:12345:%d:%s",
                              na->nip_fmt_pvt.la.nla_type == 0xFF ? "0" : ip_p,
                              na->nip_fmt_pvt.la.nla_type == 0xFF ? "lo" :
                              ((na->nip_fmt_pvt.la.nla_type ==
                              M0_NET_IP_PROTO_TCP) ? "tcp": "o2ib"),
                              na->nip_fmt_pvt.la.nla_portal, tmid);
        } else if (na->nip_format == M0_NET_IP_INET_IP_FORMAT) {
                if (na->nip_fmt_pvt.ia.nia_family != M0_NET_IP_AF_UNIX) {
                        inet_ntop(na->nip_fmt_pvt.ia.nia_family ==
                                  M0_NET_IP_AF_INET ? AF_INET : AF_INET6,
                                  &na->nip_ip_n.sn[0], ip_p, ARRAY_SIZE(ip_p));
                        rc = snprintf(buf, M0_NET_IP_STRLEN_MAX, "%s:%s:%s@%d",
                                      na->nip_fmt_pvt.ia.nia_family ==
                                      M0_NET_IP_AF_INET ? "inet" : "inet6",
                                      ip_protocol[na->nip_fmt_pvt.ia.nia_type],
                                      ip_p, na->nip_port);
                } else
                        M0_LOG(M0_ERROR, "Format is currently not supported");
        } else if (na->nip_format == M0_NET_IP_INET_HOSTNAME_FORMAT) {
                inet_ntop(AF_INET, &na->nip_ip_n.sn[0], ip_p, ARRAY_SIZE(ip_p));
                rc = m0_net_ip_to_hostname(ip_p, hostname);
                if (rc != 0 )
                        return M0_ERR(rc);
                rc = snprintf(buf, M0_NET_IP_STRLEN_MAX, "inet:%s:%s@%d",
                              ip_protocol[na->nip_fmt_pvt.ia.nia_type],
                              hostname, na->nip_port);
        }
        if (rc <= 0 || rc >= M0_NET_IP_STRLEN_MAX)
                return M0_ERR(-EINVAL);
        M0_LOG(M0_DEBUG, "Address constructed: %s", buf);

        return 0;
}

M0_INTERNAL int m0_net_hostname_to_ip(const char *hostname, char *ip,
                                      enum m0_net_ip_format *fmt)
{
        struct hostent  *hname;
        struct in_addr **addr;
        uint32_t         ip_n[4];
        int              i;
        int              n;
        char            *cp;
        char             name[M0_NET_IP_STRLEN_MAX] = {};

        M0_ENTRY("Hostname=%s", (char*)hostname);
        cp = strchr(hostname, '@');
        if (cp == NULL)
                return M0_ERR(-EINVAL);

        n = cp - hostname;
        name[n] = '\0';
        strncat(name, hostname, n);

        if (inet_pton(AF_INET, name, &ip_n[0]) == 1 ||
            inet_pton(AF_INET6, name, &ip_n[0]) == 1) {
                /* Copy ip address as it is. */
                *fmt = M0_NET_IP_INET_IP_FORMAT;
                strcpy(ip, name);
        } else {
                *fmt = M0_NET_IP_INET_HOSTNAME_FORMAT;
                hname = gethostbyname(name);
                if (hname == NULL) {
                        M0_LOG(M0_ERROR, "gethostbyname err=%d for %s",
                               h_errno, (char*)name);
                        /* Return positive rc for gethostbyname failure */
                        return M0_ERR(h_errno);
                }
                addr = (struct in_addr **)hname->h_addr_list;
                for (i = 0; addr[i] != NULL; i++) {
                        /* Return the first one. */
                        strcpy(ip, inet_ntoa(*addr[i]));
                        M0_LOG(M0_DEBUG, "fqdn=%s to ip=%s", (char*)name, ip);
                        return M0_RC(0);
                }

                /* If no valid addr structure found, then return error */
                return M0_ERR(-errno);
        }

        return M0_RC(0);
}

M0_INTERNAL bool m0_net_ip_addr_eq(const struct m0_net_ip_addr *addr1,
                                   const struct m0_net_ip_addr *addr2,
                                   bool is_ncmp)
{
        M0_PRE(addr1 != NULL && addr2 != NULL);
        if (!is_ncmp)
                return (strcmp(addr1->nia_p, addr2->nia_p) == 0);
        else
                return (addr1->nia_n.nip_format == addr2->nia_n.nip_format &&
                        addr1->nia_n.nip_port == addr2->nia_n.nip_port     &&
                        /* For lnet address compare using m0_net_ip_la_eq(). */
                        ((addr1->nia_n.nip_format == M0_NET_IP_LNET_FORMAT &&
                        m0_net_ip_la_eq(addr1, addr2))                    ||
                        /* For inet address compare using m0_net_ip_ia_eq(). */
                        (addr1->nia_n.nip_format != M0_NET_IP_LNET_FORMAT  &&
                        m0_net_ip_ia_eq(addr1, addr2))));
}

M0_INTERNAL int m0_net_ip_init(void)
{
        m0_mutex_init(&autotm_lock);
        M0_SET_ARR0(ip_autotm);
        return 0;
}

M0_INTERNAL void m0_net_ip_fini(void)
{
        m0_mutex_fini(&autotm_lock);
}

#endif /* __KERNEL__ */

#undef M0_TRACE_SUBSYSTEM

/*
 *  Local variables:
 *  c-indentation-style: "K&R"
 *  c-basic-offset: 8
 *  tab-width: 8
 *  fill-column: 80
 *  scroll-step: 1
 *  End:
 */