[funini.com] -> [kei@sodan] -> Kernel Reading

root/net/sunrpc/svcauth_unix.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. unix_domain_find
  2. svcauth_unix_domain_release
  3. ip_map_put
  4. hash_ip
  5. hash_ip6
  6. ip_map_match
  7. ip_map_init
  8. update
  9. ip_map_alloc
  10. ip_map_request
  11. ip_map_parse
  12. ip_map_show
  13. ip_map_lookup
  14. ip_map_update
  15. auth_unix_add_addr
  16. auth_unix_forget_old
  17. auth_unix_lookup
  18. svcauth_unix_purge
  19. ip_map_cached_get
  20. ip_map_cached_put
  21. svcauth_unix_info_release
  22. unix_gid_put
  23. unix_gid_match
  24. unix_gid_init
  25. unix_gid_update
  26. unix_gid_alloc
  27. unix_gid_request
  28. unix_gid_parse
  29. unix_gid_show
  30. unix_gid_lookup
  31. unix_gid_find
  32. svcauth_unix_set_client
  33. svcauth_null_accept
  34. svcauth_null_release
  35. svcauth_unix_accept
  36. svcauth_unix_release

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/svcauth.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/err.h>
#include <linux/seq_file.h>
#include <linux/hash.h>
#include <linux/string.h>
#include <net/sock.h>
#include <net/ipv6.h>
#include <linux/kernel.h>
#define RPCDBG_FACILITY RPCDBG_AUTH


/*
 * AUTHUNIX and AUTHNULL credentials are both handled here.
 * AUTHNULL is treated just like AUTHUNIX except that the uid/gid
 * are always nobody (-2).  i.e. we do the same IP address checks for
 * AUTHNULL as for AUTHUNIX, and that is done here.
 */


struct unix_domain {
        struct auth_domain      h;
        int     addr_changes;
        /* other stuff later */
};

extern struct auth_ops svcauth_unix;

struct auth_domain *unix_domain_find(char *name)
{
        struct auth_domain *rv;
        struct unix_domain *new = NULL;

        rv = auth_domain_lookup(name, NULL);
        while(1) {
                if (rv) {
                        if (new && rv != &new->h)
                                auth_domain_put(&new->h);

                        if (rv->flavour != &svcauth_unix) {
                                auth_domain_put(rv);
                                return NULL;
                        }
                        return rv;
                }

                new = kmalloc(sizeof(*new), GFP_KERNEL);
                if (new == NULL)
                        return NULL;
                kref_init(&new->h.ref);
                new->h.name = kstrdup(name, GFP_KERNEL);
                if (new->h.name == NULL) {
                        kfree(new);
                        return NULL;
                }
                new->h.flavour = &svcauth_unix;
                new->addr_changes = 0;
                rv = auth_domain_lookup(name, &new->h);
        }
}
EXPORT_SYMBOL(unix_domain_find);

static void svcauth_unix_domain_release(struct auth_domain *dom)
{
        struct unix_domain *ud = container_of(dom, struct unix_domain, h);

        kfree(dom->name);
        kfree(ud);
}


/**************************************************
 * cache for IP address to unix_domain
 * as needed by AUTH_UNIX
 */
#define IP_HASHBITS     8
#define IP_HASHMAX      (1<<IP_HASHBITS)
#define IP_HASHMASK     (IP_HASHMAX-1)

struct ip_map {
        struct cache_head       h;
        char                    m_class[8]; /* e.g. "nfsd" */
        struct in6_addr         m_addr;
        struct unix_domain      *m_client;
        int                     m_add_change;
};
static struct cache_head        *ip_table[IP_HASHMAX];

static void ip_map_put(struct kref *kref)
{
        struct cache_head *item = container_of(kref, struct cache_head, ref);
        struct ip_map *im = container_of(item, struct ip_map,h);

        if (test_bit(CACHE_VALID, &item->flags) &&
            !test_bit(CACHE_NEGATIVE, &item->flags))
                auth_domain_put(&im->m_client->h);
        kfree(im);
}

#if IP_HASHBITS == 8
/* hash_long on a 64 bit machine is currently REALLY BAD for
 * IP addresses in reverse-endian (i.e. on a little-endian machine).
 * So use a trivial but reliable hash instead
 */
static inline int hash_ip(__be32 ip)
{
        int hash = (__force u32)ip ^ ((__force u32)ip>>16);
        return (hash ^ (hash>>8)) & 0xff;
}
#endif
static inline int hash_ip6(struct in6_addr ip)
{
        return (hash_ip(ip.s6_addr32[0]) ^
                hash_ip(ip.s6_addr32[1]) ^
                hash_ip(ip.s6_addr32[2]) ^
                hash_ip(ip.s6_addr32[3]));
}
static int ip_map_match(struct cache_head *corig, struct cache_head *cnew)
{
        struct ip_map *orig = container_of(corig, struct ip_map, h);
        struct ip_map *new = container_of(cnew, struct ip_map, h);
        return strcmp(orig->m_class, new->m_class) == 0
                && ipv6_addr_equal(&orig->m_addr, &new->m_addr);
}
static void ip_map_init(struct cache_head *cnew, struct cache_head *citem)
{
        struct ip_map *new = container_of(cnew, struct ip_map, h);
        struct ip_map *item = container_of(citem, struct ip_map, h);

        strcpy(new->m_class, item->m_class);
        ipv6_addr_copy(&new->m_addr, &item->m_addr);
}
static void update(struct cache_head *cnew, struct cache_head *citem)
{
        struct ip_map *new = container_of(cnew, struct ip_map, h);
        struct ip_map *item = container_of(citem, struct ip_map, h);

        kref_get(&item->m_client->h.ref);
        new->m_client = item->m_client;
        new->m_add_change = item->m_add_change;
}
static struct cache_head *ip_map_alloc(void)
{
        struct ip_map *i = kmalloc(sizeof(*i), GFP_KERNEL);
        if (i)
                return &i->h;
        else
                return NULL;
}

static void ip_map_request(struct cache_detail *cd,
                                  struct cache_head *h,
                                  char **bpp, int *blen)
{
        char text_addr[40];
        struct ip_map *im = container_of(h, struct ip_map, h);

        if (ipv6_addr_v4mapped(&(im->m_addr))) {
                snprintf(text_addr, 20, NIPQUAD_FMT,
                                ntohl(im->m_addr.s6_addr32[3]) >> 24 & 0xff,
                                ntohl(im->m_addr.s6_addr32[3]) >> 16 & 0xff,
                                ntohl(im->m_addr.s6_addr32[3]) >>  8 & 0xff,
                                ntohl(im->m_addr.s6_addr32[3]) >>  0 & 0xff);
        } else {
                snprintf(text_addr, 40, NIP6_FMT, NIP6(im->m_addr));
        }
        qword_add(bpp, blen, im->m_class);
        qword_add(bpp, blen, text_addr);
        (*bpp)[-1] = '\n';
}

static struct ip_map *ip_map_lookup(char *class, struct in6_addr *addr);
static int ip_map_update(struct ip_map *ipm, struct unix_domain *udom, time_t expiry);

static int ip_map_parse(struct cache_detail *cd,
                          char *mesg, int mlen)
{
        /* class ipaddress [domainname] */
        /* should be safe just to use the start of the input buffer
         * for scratch: */
        char *buf = mesg;
        int len;
        int b1, b2, b3, b4, b5, b6, b7, b8;
        char c;
        char class[8];
        struct in6_addr addr;
        int err;

        struct ip_map *ipmp;
        struct auth_domain *dom;
        time_t expiry;

        if (mesg[mlen-1] != '\n')
                return -EINVAL;
        mesg[mlen-1] = 0;

        /* class */
        len = qword_get(&mesg, class, sizeof(class));
        if (len <= 0) return -EINVAL;

        /* ip address */
        len = qword_get(&mesg, buf, mlen);
        if (len <= 0) return -EINVAL;

        if (sscanf(buf, NIPQUAD_FMT "%c", &b1, &b2, &b3, &b4, &c) == 4) {
                addr.s6_addr32[0] = 0;
                addr.s6_addr32[1] = 0;
                addr.s6_addr32[2] = htonl(0xffff);
                addr.s6_addr32[3] =
                        htonl((((((b1<<8)|b2)<<8)|b3)<<8)|b4);
       } else if (sscanf(buf, NIP6_FMT "%c",
                        &b1, &b2, &b3, &b4, &b5, &b6, &b7, &b8, &c) == 8) {
                addr.s6_addr16[0] = htons(b1);
                addr.s6_addr16[1] = htons(b2);
                addr.s6_addr16[2] = htons(b3);
                addr.s6_addr16[3] = htons(b4);
                addr.s6_addr16[4] = htons(b5);
                addr.s6_addr16[5] = htons(b6);
                addr.s6_addr16[6] = htons(b7);
                addr.s6_addr16[7] = htons(b8);
       } else
                return -EINVAL;

        expiry = get_expiry(&mesg);
        if (expiry ==0)
                return -EINVAL;

        /* domainname, or empty for NEGATIVE */
        len = qword_get(&mesg, buf, mlen);
        if (len < 0) return -EINVAL;

        if (len) {
                dom = unix_domain_find(buf);
                if (dom == NULL)
                        return -ENOENT;
        } else
                dom = NULL;

        ipmp = ip_map_lookup(class, &addr);
        if (ipmp) {
                err = ip_map_update(ipmp,
                             container_of(dom, struct unix_domain, h),
                             expiry);
        } else
                err = -ENOMEM;

        if (dom)
                auth_domain_put(dom);

        cache_flush();
        return err;
}

static int ip_map_show(struct seq_file *m,
                       struct cache_detail *cd,
                       struct cache_head *h)
{
        struct ip_map *im;
        struct in6_addr addr;
        char *dom = "-no-domain-";

        if (h == NULL) {
                seq_puts(m, "#class IP domain\n");
                return 0;
        }
        im = container_of(h, struct ip_map, h);
        /* class addr domain */
        ipv6_addr_copy(&addr, &im->m_addr);

        if (test_bit(CACHE_VALID, &h->flags) &&
            !test_bit(CACHE_NEGATIVE, &h->flags))
                dom = im->m_client->h.name;

        if (ipv6_addr_v4mapped(&addr)) {
                seq_printf(m, "%s " NIPQUAD_FMT " %s\n",
                        im->m_class,
                        ntohl(addr.s6_addr32[3]) >> 24 & 0xff,
                        ntohl(addr.s6_addr32[3]) >> 16 & 0xff,
                        ntohl(addr.s6_addr32[3]) >>  8 & 0xff,
                        ntohl(addr.s6_addr32[3]) >>  0 & 0xff,
                        dom);
        } else {
                seq_printf(m, "%s " NIP6_FMT " %s\n",
                        im->m_class, NIP6(addr), dom);
        }
        return 0;
}


struct cache_detail ip_map_cache = {
        .owner          = THIS_MODULE,
        .hash_size      = IP_HASHMAX,
        .hash_table     = ip_table,
        .name           = "auth.unix.ip",
        .cache_put      = ip_map_put,
        .cache_request  = ip_map_request,
        .cache_parse    = ip_map_parse,
        .cache_show     = ip_map_show,
        .match          = ip_map_match,
        .init           = ip_map_init,
        .update         = update,
        .alloc          = ip_map_alloc,
};

static struct ip_map *ip_map_lookup(char *class, struct in6_addr *addr)
{
        struct ip_map ip;
        struct cache_head *ch;

        strcpy(ip.m_class, class);
        ipv6_addr_copy(&ip.m_addr, addr);
        ch = sunrpc_cache_lookup(&ip_map_cache, &ip.h,
                                 hash_str(class, IP_HASHBITS) ^
                                 hash_ip6(*addr));

        if (ch)
                return container_of(ch, struct ip_map, h);
        else
                return NULL;
}

static int ip_map_update(struct ip_map *ipm, struct unix_domain *udom, time_t expiry)
{
        struct ip_map ip;
        struct cache_head *ch;

        ip.m_client = udom;
        ip.h.flags = 0;
        if (!udom)
                set_bit(CACHE_NEGATIVE, &ip.h.flags);
        else {
                ip.m_add_change = udom->addr_changes;
                /* if this is from the legacy set_client system call,
                 * we need m_add_change to be one higher
                 */
                if (expiry == NEVER)
                        ip.m_add_change++;
        }
        ip.h.expiry_time = expiry;
        ch = sunrpc_cache_update(&ip_map_cache,
                                 &ip.h, &ipm->h,
                                 hash_str(ipm->m_class, IP_HASHBITS) ^
                                 hash_ip6(ipm->m_addr));
        if (!ch)
                return -ENOMEM;
        cache_put(ch, &ip_map_cache);
        return 0;
}

int auth_unix_add_addr(struct in6_addr *addr, struct auth_domain *dom)
{
        struct unix_domain *udom;
        struct ip_map *ipmp;

        if (dom->flavour != &svcauth_unix)
                return -EINVAL;
        udom = container_of(dom, struct unix_domain, h);
        ipmp = ip_map_lookup("nfsd", addr);

        if (ipmp)
                return ip_map_update(ipmp, udom, NEVER);
        else
                return -ENOMEM;
}
EXPORT_SYMBOL(auth_unix_add_addr);

int auth_unix_forget_old(struct auth_domain *dom)
{
        struct unix_domain *udom;

        if (dom->flavour != &svcauth_unix)
                return -EINVAL;
        udom = container_of(dom, struct unix_domain, h);
        udom->addr_changes++;
        return 0;
}
EXPORT_SYMBOL(auth_unix_forget_old);

struct auth_domain *auth_unix_lookup(struct in6_addr *addr)
{
        struct ip_map *ipm;
        struct auth_domain *rv;

        ipm = ip_map_lookup("nfsd", addr);

        if (!ipm)
                return NULL;
        if (cache_check(&ip_map_cache, &ipm->h, NULL))
                return NULL;

        if ((ipm->m_client->addr_changes - ipm->m_add_change) >0) {
                if (test_and_set_bit(CACHE_NEGATIVE, &ipm->h.flags) == 0)
                        auth_domain_put(&ipm->m_client->h);
                rv = NULL;
        } else {
                rv = &ipm->m_client->h;
                kref_get(&rv->ref);
        }
        cache_put(&ipm->h, &ip_map_cache);
        return rv;
}
EXPORT_SYMBOL(auth_unix_lookup);

void svcauth_unix_purge(void)
{
        cache_purge(&ip_map_cache);
}
EXPORT_SYMBOL(svcauth_unix_purge);

static inline struct ip_map *
ip_map_cached_get(struct svc_rqst *rqstp)
{
        struct ip_map *ipm = NULL;
        struct svc_xprt *xprt = rqstp->rq_xprt;

        if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
                spin_lock(&xprt->xpt_lock);
                ipm = xprt->xpt_auth_cache;
                if (ipm != NULL) {
                        if (!cache_valid(&ipm->h)) {
                                /*
                                 * The entry has been invalidated since it was
                                 * remembered, e.g. by a second mount from the
                                 * same IP address.
                                 */
                                xprt->xpt_auth_cache = NULL;
                                spin_unlock(&xprt->xpt_lock);
                                cache_put(&ipm->h, &ip_map_cache);
                                return NULL;
                        }
                        cache_get(&ipm->h);
                }
                spin_unlock(&xprt->xpt_lock);
        }
        return ipm;
}

static inline void
ip_map_cached_put(struct svc_rqst *rqstp, struct ip_map *ipm)
{
        struct svc_xprt *xprt = rqstp->rq_xprt;

        if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) {
                spin_lock(&xprt->xpt_lock);
                if (xprt->xpt_auth_cache == NULL) {
                        /* newly cached, keep the reference */
                        xprt->xpt_auth_cache = ipm;
                        ipm = NULL;
                }
                spin_unlock(&xprt->xpt_lock);
        }
        if (ipm)
                cache_put(&ipm->h, &ip_map_cache);
}

void
svcauth_unix_info_release(void *info)
{
        struct ip_map *ipm = info;
        cache_put(&ipm->h, &ip_map_cache);
}

/****************************************************************************
 * auth.unix.gid cache
 * simple cache to map a UID to a list of GIDs
 * because AUTH_UNIX aka AUTH_SYS has a max of 16
 */
#define GID_HASHBITS    8
#define GID_HASHMAX     (1<<GID_HASHBITS)
#define GID_HASHMASK    (GID_HASHMAX - 1)

struct unix_gid {
        struct cache_head       h;
        uid_t                   uid;
        struct group_info       *gi;
};
static struct cache_head        *gid_table[GID_HASHMAX];

static void unix_gid_put(struct kref *kref)
{
        struct cache_head *item = container_of(kref, struct cache_head, ref);
        struct unix_gid *ug = container_of(item, struct unix_gid, h);
        if (test_bit(CACHE_VALID, &item->flags) &&
            !test_bit(CACHE_NEGATIVE, &item->flags))
                put_group_info(ug->gi);
        kfree(ug);
}

static int unix_gid_match(struct cache_head *corig, struct cache_head *cnew)
{
        struct unix_gid *orig = container_of(corig, struct unix_gid, h);
        struct unix_gid *new = container_of(cnew, struct unix_gid, h);
        return orig->uid == new->uid;
}
static void unix_gid_init(struct cache_head *cnew, struct cache_head *citem)
{
        struct unix_gid *new = container_of(cnew, struct unix_gid, h);
        struct unix_gid *item = container_of(citem, struct unix_gid, h);
        new->uid = item->uid;
}
static void unix_gid_update(struct cache_head *cnew, struct cache_head *citem)
{
        struct unix_gid *new = container_of(cnew, struct unix_gid, h);
        struct unix_gid *item = container_of(citem, struct unix_gid, h);

        get_group_info(item->gi);
        new->gi = item->gi;
}
static struct cache_head *unix_gid_alloc(void)
{
        struct unix_gid *g = kmalloc(sizeof(*g), GFP_KERNEL);
        if (g)
                return &g->h;
        else
                return NULL;
}

static void unix_gid_request(struct cache_detail *cd,
                             struct cache_head *h,
                             char **bpp, int *blen)
{
        char tuid[20];
        struct unix_gid *ug = container_of(h, struct unix_gid, h);

        snprintf(tuid, 20, "%u", ug->uid);
        qword_add(bpp, blen, tuid);
        (*bpp)[-1] = '\n';
}

static struct unix_gid *unix_gid_lookup(uid_t uid);
extern struct cache_detail unix_gid_cache;

static int unix_gid_parse(struct cache_detail *cd,
                        char *mesg, int mlen)
{
        /* uid expiry Ngid gid0 gid1 ... gidN-1 */
        int uid;
        int gids;
        int rv;
        int i;
        int err;
        time_t expiry;
        struct unix_gid ug, *ugp;

        if (mlen <= 0 || mesg[mlen-1] != '\n')
                return -EINVAL;
        mesg[mlen-1] = 0;

        rv = get_int(&mesg, &uid);
        if (rv)
                return -EINVAL;
        ug.uid = uid;

        expiry = get_expiry(&mesg);
        if (expiry == 0)
                return -EINVAL;

        rv = get_int(&mesg, &gids);
        if (rv || gids < 0 || gids > 8192)
                return -EINVAL;

        ug.gi = groups_alloc(gids);
        if (!ug.gi)
                return -ENOMEM;

        for (i = 0 ; i < gids ; i++) {
                int gid;
                rv = get_int(&mesg, &gid);
                err = -EINVAL;
                if (rv)
                        goto out;
                GROUP_AT(ug.gi, i) = gid;
        }

        ugp = unix_gid_lookup(uid);
        if (ugp) {
                struct cache_head *ch;
                ug.h.flags = 0;
                ug.h.expiry_time = expiry;
                ch = sunrpc_cache_update(&unix_gid_cache,
                                         &ug.h, &ugp->h,
                                         hash_long(uid, GID_HASHBITS));
                if (!ch)
                        err = -ENOMEM;
                else {
                        err = 0;
                        cache_put(ch, &unix_gid_cache);
                }
        } else
                err = -ENOMEM;
 out:
        if (ug.gi)
                put_group_info(ug.gi);
        return err;
}

static int unix_gid_show(struct seq_file *m,
                         struct cache_detail *cd,
                         struct cache_head *h)
{
        struct unix_gid *ug;
        int i;
        int glen;

        if (h == NULL) {
                seq_puts(m, "#uid cnt: gids...\n");
                return 0;
        }
        ug = container_of(h, struct unix_gid, h);
        if (test_bit(CACHE_VALID, &h->flags) &&
            !test_bit(CACHE_NEGATIVE, &h->flags))
                glen = ug->gi->ngroups;
        else
                glen = 0;

        seq_printf(m, "%d %d:", ug->uid, glen);
        for (i = 0; i < glen; i++)
                seq_printf(m, " %d", GROUP_AT(ug->gi, i));
        seq_printf(m, "\n");
        return 0;
}

struct cache_detail unix_gid_cache = {
        .owner          = THIS_MODULE,
        .hash_size      = GID_HASHMAX,
        .hash_table     = gid_table,
        .name           = "auth.unix.gid",
        .cache_put      = unix_gid_put,
        .cache_request  = unix_gid_request,
        .cache_parse    = unix_gid_parse,
        .cache_show     = unix_gid_show,
        .match          = unix_gid_match,
        .init           = unix_gid_init,
        .update         = unix_gid_update,
        .alloc          = unix_gid_alloc,
};

static struct unix_gid *unix_gid_lookup(uid_t uid)
{
        struct unix_gid ug;
        struct cache_head *ch;

        ug.uid = uid;
        ch = sunrpc_cache_lookup(&unix_gid_cache, &ug.h,
                                 hash_long(uid, GID_HASHBITS));
        if (ch)
                return container_of(ch, struct unix_gid, h);
        else
                return NULL;
}

static int unix_gid_find(uid_t uid, struct group_info **gip,
                         struct svc_rqst *rqstp)
{
        struct unix_gid *ug = unix_gid_lookup(uid);
        if (!ug)
                return -EAGAIN;
        switch (cache_check(&unix_gid_cache, &ug->h, &rqstp->rq_chandle)) {
        case -ENOENT:
                *gip = NULL;
                return 0;
        case 0:
                *gip = ug->gi;
                get_group_info(*gip);
                return 0;
        default:
                return -EAGAIN;
        }
}

int
svcauth_unix_set_client(struct svc_rqst *rqstp)
{
        struct sockaddr_in *sin;
        struct sockaddr_in6 *sin6, sin6_storage;
        struct ip_map *ipm;

        switch (rqstp->rq_addr.ss_family) {
        case AF_INET:
                sin = svc_addr_in(rqstp);
                sin6 = &sin6_storage;
                ipv6_addr_set(&sin6->sin6_addr, 0, 0,
                                htonl(0x0000FFFF), sin->sin_addr.s_addr);
                break;
        case AF_INET6:
                sin6 = svc_addr_in6(rqstp);
                break;
        default:
                BUG();
        }

        rqstp->rq_client = NULL;
        if (rqstp->rq_proc == 0)
                return SVC_OK;

        ipm = ip_map_cached_get(rqstp);
        if (ipm == NULL)
                ipm = ip_map_lookup(rqstp->rq_server->sv_program->pg_class,
                                    &sin6->sin6_addr);

        if (ipm == NULL)
                return SVC_DENIED;

        switch (cache_check(&ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
                default:
                        BUG();
                case -EAGAIN:
                case -ETIMEDOUT:
                        return SVC_DROP;
                case -ENOENT:
                        return SVC_DENIED;
                case 0:
                        rqstp->rq_client = &ipm->m_client->h;
                        kref_get(&rqstp->rq_client->ref);
                        ip_map_cached_put(rqstp, ipm);
                        break;
        }
        return SVC_OK;
}

EXPORT_SYMBOL(svcauth_unix_set_client);

static int
svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
{
        struct kvec     *argv = &rqstp->rq_arg.head[0];
        struct kvec     *resv = &rqstp->rq_res.head[0];
        struct svc_cred *cred = &rqstp->rq_cred;

        cred->cr_group_info = NULL;
        rqstp->rq_client = NULL;

        if (argv->iov_len < 3*4)
                return SVC_GARBAGE;

        if (svc_getu32(argv) != 0) {
                dprintk("svc: bad null cred\n");
                *authp = rpc_autherr_badcred;
                return SVC_DENIED;
        }
        if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
                dprintk("svc: bad null verf\n");
                *authp = rpc_autherr_badverf;
                return SVC_DENIED;
        }

        /* Signal that mapping to nobody uid/gid is required */
        cred->cr_uid = (uid_t) -1;
        cred->cr_gid = (gid_t) -1;
        cred->cr_group_info = groups_alloc(0);
        if (cred->cr_group_info == NULL)
                return SVC_DROP; /* kmalloc failure - client must retry */

        /* Put NULL verifier */
        svc_putnl(resv, RPC_AUTH_NULL);
        svc_putnl(resv, 0);

        rqstp->rq_flavor = RPC_AUTH_NULL;
        return SVC_OK;
}

static int
svcauth_null_release(struct svc_rqst *rqstp)
{
        if (rqstp->rq_client)
                auth_domain_put(rqstp->rq_client);
        rqstp->rq_client = NULL;
        if (rqstp->rq_cred.cr_group_info)
                put_group_info(rqstp->rq_cred.cr_group_info);
        rqstp->rq_cred.cr_group_info = NULL;

        return 0; /* don't drop */
}


struct auth_ops svcauth_null = {
        .name           = "null",
        .owner          = THIS_MODULE,
        .flavour        = RPC_AUTH_NULL,
        .accept         = svcauth_null_accept,
        .release        = svcauth_null_release,
        .set_client     = svcauth_unix_set_client,
};


static int
svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
{
        struct kvec     *argv = &rqstp->rq_arg.head[0];
        struct kvec     *resv = &rqstp->rq_res.head[0];
        struct svc_cred *cred = &rqstp->rq_cred;
        u32             slen, i;
        int             len   = argv->iov_len;

        cred->cr_group_info = NULL;
        rqstp->rq_client = NULL;

        if ((len -= 3*4) < 0)
                return SVC_GARBAGE;

        svc_getu32(argv);                       /* length */
        svc_getu32(argv);                       /* time stamp */
        slen = XDR_QUADLEN(svc_getnl(argv));    /* machname length */
        if (slen > 64 || (len -= (slen + 3)*4) < 0)
                goto badcred;
        argv->iov_base = (void*)((__be32*)argv->iov_base + slen);       /* skip machname */
        argv->iov_len -= slen*4;

        cred->cr_uid = svc_getnl(argv);         /* uid */
        cred->cr_gid = svc_getnl(argv);         /* gid */
        slen = svc_getnl(argv);                 /* gids length */
        if (slen > 16 || (len -= (slen + 2)*4) < 0)
                goto badcred;
        if (unix_gid_find(cred->cr_uid, &cred->cr_group_info, rqstp)
            == -EAGAIN)
                return SVC_DROP;
        if (cred->cr_group_info == NULL) {
                cred->cr_group_info = groups_alloc(slen);
                if (cred->cr_group_info == NULL)
                        return SVC_DROP;
                for (i = 0; i < slen; i++)
                        GROUP_AT(cred->cr_group_info, i) = svc_getnl(argv);
        } else {
                for (i = 0; i < slen ; i++)
                        svc_getnl(argv);
        }
        if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
                *authp = rpc_autherr_badverf;
                return SVC_DENIED;
        }

        /* Put NULL verifier */
        svc_putnl(resv, RPC_AUTH_NULL);
        svc_putnl(resv, 0);

        rqstp->rq_flavor = RPC_AUTH_UNIX;
        return SVC_OK;

badcred:
        *authp = rpc_autherr_badcred;
        return SVC_DENIED;
}

static int
svcauth_unix_release(struct svc_rqst *rqstp)
{
        /* Verifier (such as it is) is already in place.
         */
        if (rqstp->rq_client)
                auth_domain_put(rqstp->rq_client);
        rqstp->rq_client = NULL;
        if (rqstp->rq_cred.cr_group_info)
                put_group_info(rqstp->rq_cred.cr_group_info);
        rqstp->rq_cred.cr_group_info = NULL;

        return 0;
}


struct auth_ops svcauth_unix = {
        .name           = "unix",
        .owner          = THIS_MODULE,
        .flavour        = RPC_AUTH_UNIX,
        .accept         = svcauth_unix_accept,
        .release        = svcauth_unix_release,
        .domain_release = svcauth_unix_domain_release,
        .set_client     = svcauth_unix_set_client,
};


/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading