WSL2-Linux-Kernel/net/sunrpc/svcauth_unix.c

550 строки
12 KiB
C

#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/err.h>
#include <linux/seq_file.h>
#include <linux/hash.h>
#include <linux/string.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);
new->h.flavour = &svcauth_unix;
new->addr_changes = 0;
rv = auth_domain_lookup(name, &new->h);
}
}
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 in_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(unsigned long ip)
{
int hash = ip ^ (ip>>16);
return (hash ^ (hash>>8)) & 0xff;
}
#endif
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
&& orig->m_addr.s_addr == new->m_addr.s_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);
new->m_addr.s_addr = item->m_addr.s_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[20];
struct ip_map *im = container_of(h, struct ip_map, h);
__u32 addr = im->m_addr.s_addr;
snprintf(text_addr, 20, "%u.%u.%u.%u",
ntohl(addr) >> 24 & 0xff,
ntohl(addr) >> 16 & 0xff,
ntohl(addr) >> 8 & 0xff,
ntohl(addr) >> 0 & 0xff);
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 in_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;
char c;
char class[8];
struct in_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, "%u.%u.%u.%u%c", &b1, &b2, &b3, &b4, &c) != 4)
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;
addr.s_addr =
htonl((((((b1<<8)|b2)<<8)|b3)<<8)|b4);
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 in_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 */
addr = im->m_addr;
if (test_bit(CACHE_VALID, &h->flags) &&
!test_bit(CACHE_NEGATIVE, &h->flags))
dom = im->m_client->h.name;
seq_printf(m, "%s %d.%d.%d.%d %s\n",
im->m_class,
htonl(addr.s_addr) >> 24 & 0xff,
htonl(addr.s_addr) >> 16 & 0xff,
htonl(addr.s_addr) >> 8 & 0xff,
htonl(addr.s_addr) >> 0 & 0xff,
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 in_addr addr)
{
struct ip_map ip;
struct cache_head *ch;
strcpy(ip.m_class, class);
ip.m_addr = addr;
ch = sunrpc_cache_lookup(&ip_map_cache, &ip.h,
hash_str(class, IP_HASHBITS) ^
hash_ip((unsigned long)addr.s_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_ip((unsigned long)ipm->m_addr.s_addr));
if (!ch)
return -ENOMEM;
cache_put(ch, &ip_map_cache);
return 0;
}
int auth_unix_add_addr(struct in_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;
}
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;
}
struct auth_domain *auth_unix_lookup(struct in_addr addr)
{
struct ip_map key, *ipm;
struct auth_domain *rv;
strcpy(key.m_class, "nfsd");
key.m_addr = addr;
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;
}
void svcauth_unix_purge(void)
{
cache_purge(&ip_map_cache);
}
static int
svcauth_unix_set_client(struct svc_rqst *rqstp)
{
struct ip_map *ipm;
rqstp->rq_client = NULL;
if (rqstp->rq_proc == 0)
return SVC_OK;
ipm = ip_map_lookup(rqstp->rq_server->sv_program->pg_class,
rqstp->rq_addr.sin_addr);
if (ipm == NULL)
return SVC_DENIED;
switch (cache_check(&ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
default:
BUG();
case -EAGAIN:
return SVC_DROP;
case -ENOENT:
return SVC_DENIED;
case 0:
rqstp->rq_client = &ipm->m_client->h;
kref_get(&rqstp->rq_client->ref);
cache_put(&ipm->h, &ip_map_cache);
break;
}
return SVC_OK;
}
static int
svcauth_null_accept(struct svc_rqst *rqstp, u32 *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) != 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_putu32(resv, RPC_AUTH_NULL);
svc_putu32(resv, 0);
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, u32 *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(ntohl(svc_getu32(argv))); /* machname length */
if (slen > 64 || (len -= (slen + 3)*4) < 0)
goto badcred;
argv->iov_base = (void*)((u32*)argv->iov_base + slen); /* skip machname */
argv->iov_len -= slen*4;
cred->cr_uid = ntohl(svc_getu32(argv)); /* uid */
cred->cr_gid = ntohl(svc_getu32(argv)); /* gid */
slen = ntohl(svc_getu32(argv)); /* gids length */
if (slen > 16 || (len -= (slen + 2)*4) < 0)
goto badcred;
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) = ntohl(svc_getu32(argv));
if (svc_getu32(argv) != RPC_AUTH_NULL || svc_getu32(argv) != 0) {
*authp = rpc_autherr_badverf;
return SVC_DENIED;
}
/* Put NULL verifier */
svc_putu32(resv, RPC_AUTH_NULL);
svc_putu32(resv, 0);
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,
};