linux/net/sunrpc/auth_gss/gss_mech_switch.c
Chuck Lever 65b80179f9 xprtrdma: No direct data placement with krb5i and krb5p
Direct data placement is not allowed when using flavors that
guarantee integrity or privacy. When such security flavors are in
effect, don't allow the use of Read and Write chunks for moving
individual data items. All messages larger than the inline threshold
are sent via Long Call or Long Reply.

On my systems (CX-3 Pro on FDR), for small I/O operations, the use
of Long messages adds only around 5 usecs of latency in each
direction.

Note that when integrity or encryption is used, the host CPU touches
every byte in these messages. Even if it could be used, data
movement offload doesn't buy much in this case.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-07-11 15:50:43 -04:00

494 lines
12 KiB
C

/*
* linux/net/sunrpc/gss_mech_switch.c
*
* Copyright (c) 2001 The Regents of the University of Michigan.
* All rights reserved.
*
* J. Bruce Fields <bfields@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/oid_registry.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/gss_asn1.h>
#include <linux/sunrpc/auth_gss.h>
#include <linux/sunrpc/svcauth_gss.h>
#include <linux/sunrpc/gss_err.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/sunrpc/clnt.h>
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
static LIST_HEAD(registered_mechs);
static DEFINE_SPINLOCK(registered_mechs_lock);
static void
gss_mech_free(struct gss_api_mech *gm)
{
struct pf_desc *pf;
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
pf = &gm->gm_pfs[i];
kfree(pf->auth_domain_name);
pf->auth_domain_name = NULL;
}
}
static inline char *
make_auth_domain_name(char *name)
{
static char *prefix = "gss/";
char *new;
new = kmalloc(strlen(name) + strlen(prefix) + 1, GFP_KERNEL);
if (new) {
strcpy(new, prefix);
strcat(new, name);
}
return new;
}
static int
gss_mech_svc_setup(struct gss_api_mech *gm)
{
struct pf_desc *pf;
int i, status;
for (i = 0; i < gm->gm_pf_num; i++) {
pf = &gm->gm_pfs[i];
pf->auth_domain_name = make_auth_domain_name(pf->name);
status = -ENOMEM;
if (pf->auth_domain_name == NULL)
goto out;
status = svcauth_gss_register_pseudoflavor(pf->pseudoflavor,
pf->auth_domain_name);
if (status)
goto out;
}
return 0;
out:
gss_mech_free(gm);
return status;
}
/**
* gss_mech_register - register a GSS mechanism
* @gm: GSS mechanism handle
*
* Returns zero if successful, or a negative errno.
*/
int gss_mech_register(struct gss_api_mech *gm)
{
int status;
status = gss_mech_svc_setup(gm);
if (status)
return status;
spin_lock(&registered_mechs_lock);
list_add(&gm->gm_list, &registered_mechs);
spin_unlock(&registered_mechs_lock);
dprintk("RPC: registered gss mechanism %s\n", gm->gm_name);
return 0;
}
EXPORT_SYMBOL_GPL(gss_mech_register);
/**
* gss_mech_unregister - release a GSS mechanism
* @gm: GSS mechanism handle
*
*/
void gss_mech_unregister(struct gss_api_mech *gm)
{
spin_lock(&registered_mechs_lock);
list_del(&gm->gm_list);
spin_unlock(&registered_mechs_lock);
dprintk("RPC: unregistered gss mechanism %s\n", gm->gm_name);
gss_mech_free(gm);
}
EXPORT_SYMBOL_GPL(gss_mech_unregister);
struct gss_api_mech *gss_mech_get(struct gss_api_mech *gm)
{
__module_get(gm->gm_owner);
return gm;
}
EXPORT_SYMBOL(gss_mech_get);
static struct gss_api_mech *
_gss_mech_get_by_name(const char *name)
{
struct gss_api_mech *pos, *gm = NULL;
spin_lock(&registered_mechs_lock);
list_for_each_entry(pos, &registered_mechs, gm_list) {
if (0 == strcmp(name, pos->gm_name)) {
if (try_module_get(pos->gm_owner))
gm = pos;
break;
}
}
spin_unlock(&registered_mechs_lock);
return gm;
}
struct gss_api_mech * gss_mech_get_by_name(const char *name)
{
struct gss_api_mech *gm = NULL;
gm = _gss_mech_get_by_name(name);
if (!gm) {
request_module("rpc-auth-gss-%s", name);
gm = _gss_mech_get_by_name(name);
}
return gm;
}
struct gss_api_mech *gss_mech_get_by_OID(struct rpcsec_gss_oid *obj)
{
struct gss_api_mech *pos, *gm = NULL;
char buf[32];
if (sprint_oid(obj->data, obj->len, buf, sizeof(buf)) < 0)
return NULL;
dprintk("RPC: %s(%s)\n", __func__, buf);
request_module("rpc-auth-gss-%s", buf);
spin_lock(&registered_mechs_lock);
list_for_each_entry(pos, &registered_mechs, gm_list) {
if (obj->len == pos->gm_oid.len) {
if (0 == memcmp(obj->data, pos->gm_oid.data, obj->len)) {
if (try_module_get(pos->gm_owner))
gm = pos;
break;
}
}
}
spin_unlock(&registered_mechs_lock);
return gm;
}
static inline int
mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
{
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
return 1;
}
return 0;
}
static struct gss_api_mech *_gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
{
struct gss_api_mech *gm = NULL, *pos;
spin_lock(&registered_mechs_lock);
list_for_each_entry(pos, &registered_mechs, gm_list) {
if (!mech_supports_pseudoflavor(pos, pseudoflavor))
continue;
if (try_module_get(pos->gm_owner))
gm = pos;
break;
}
spin_unlock(&registered_mechs_lock);
return gm;
}
struct gss_api_mech *
gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
{
struct gss_api_mech *gm;
gm = _gss_mech_get_by_pseudoflavor(pseudoflavor);
if (!gm) {
request_module("rpc-auth-gss-%u", pseudoflavor);
gm = _gss_mech_get_by_pseudoflavor(pseudoflavor);
}
return gm;
}
/**
* gss_mech_list_pseudoflavors - Discover registered GSS pseudoflavors
* @array: array to fill in
* @size: size of "array"
*
* Returns the number of array items filled in, or a negative errno.
*
* The returned array is not sorted by any policy. Callers should not
* rely on the order of the items in the returned array.
*/
int gss_mech_list_pseudoflavors(rpc_authflavor_t *array_ptr, int size)
{
struct gss_api_mech *pos = NULL;
int j, i = 0;
spin_lock(&registered_mechs_lock);
list_for_each_entry(pos, &registered_mechs, gm_list) {
for (j = 0; j < pos->gm_pf_num; j++) {
if (i >= size) {
spin_unlock(&registered_mechs_lock);
return -ENOMEM;
}
array_ptr[i++] = pos->gm_pfs[j].pseudoflavor;
}
}
spin_unlock(&registered_mechs_lock);
return i;
}
/**
* gss_svc_to_pseudoflavor - map a GSS service number to a pseudoflavor
* @gm: GSS mechanism handle
* @qop: GSS quality-of-protection value
* @service: GSS service value
*
* Returns a matching security flavor, or RPC_AUTH_MAXFLAVOR if none is found.
*/
rpc_authflavor_t gss_svc_to_pseudoflavor(struct gss_api_mech *gm, u32 qop,
u32 service)
{
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].qop == qop &&
gm->gm_pfs[i].service == service) {
return gm->gm_pfs[i].pseudoflavor;
}
}
return RPC_AUTH_MAXFLAVOR;
}
/**
* gss_mech_info2flavor - look up a pseudoflavor given a GSS tuple
* @info: a GSS mech OID, quality of protection, and service value
*
* Returns a matching pseudoflavor, or RPC_AUTH_MAXFLAVOR if the tuple is
* not supported.
*/
rpc_authflavor_t gss_mech_info2flavor(struct rpcsec_gss_info *info)
{
rpc_authflavor_t pseudoflavor;
struct gss_api_mech *gm;
gm = gss_mech_get_by_OID(&info->oid);
if (gm == NULL)
return RPC_AUTH_MAXFLAVOR;
pseudoflavor = gss_svc_to_pseudoflavor(gm, info->qop, info->service);
gss_mech_put(gm);
return pseudoflavor;
}
/**
* gss_mech_flavor2info - look up a GSS tuple for a given pseudoflavor
* @pseudoflavor: GSS pseudoflavor to match
* @info: rpcsec_gss_info structure to fill in
*
* Returns zero and fills in "info" if pseudoflavor matches a
* supported mechanism. Otherwise a negative errno is returned.
*/
int gss_mech_flavor2info(rpc_authflavor_t pseudoflavor,
struct rpcsec_gss_info *info)
{
struct gss_api_mech *gm;
int i;
gm = gss_mech_get_by_pseudoflavor(pseudoflavor);
if (gm == NULL)
return -ENOENT;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].pseudoflavor == pseudoflavor) {
memcpy(info->oid.data, gm->gm_oid.data, gm->gm_oid.len);
info->oid.len = gm->gm_oid.len;
info->qop = gm->gm_pfs[i].qop;
info->service = gm->gm_pfs[i].service;
gss_mech_put(gm);
return 0;
}
}
gss_mech_put(gm);
return -ENOENT;
}
u32
gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
{
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
return gm->gm_pfs[i].service;
}
return 0;
}
EXPORT_SYMBOL(gss_pseudoflavor_to_service);
bool
gss_pseudoflavor_to_datatouch(struct gss_api_mech *gm, u32 pseudoflavor)
{
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
return gm->gm_pfs[i].datatouch;
}
return false;
}
char *
gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
{
int i;
for (i = 0; i < gm->gm_pf_num; i++) {
if (gm->gm_pfs[i].service == service)
return gm->gm_pfs[i].auth_domain_name;
}
return NULL;
}
void
gss_mech_put(struct gss_api_mech * gm)
{
if (gm)
module_put(gm->gm_owner);
}
EXPORT_SYMBOL(gss_mech_put);
/* The mech could probably be determined from the token instead, but it's just
* as easy for now to pass it in. */
int
gss_import_sec_context(const void *input_token, size_t bufsize,
struct gss_api_mech *mech,
struct gss_ctx **ctx_id,
time_t *endtime,
gfp_t gfp_mask)
{
if (!(*ctx_id = kzalloc(sizeof(**ctx_id), gfp_mask)))
return -ENOMEM;
(*ctx_id)->mech_type = gss_mech_get(mech);
return mech->gm_ops->gss_import_sec_context(input_token, bufsize,
*ctx_id, endtime, gfp_mask);
}
/* gss_get_mic: compute a mic over message and return mic_token. */
u32
gss_get_mic(struct gss_ctx *context_handle,
struct xdr_buf *message,
struct xdr_netobj *mic_token)
{
return context_handle->mech_type->gm_ops
->gss_get_mic(context_handle,
message,
mic_token);
}
/* gss_verify_mic: check whether the provided mic_token verifies message. */
u32
gss_verify_mic(struct gss_ctx *context_handle,
struct xdr_buf *message,
struct xdr_netobj *mic_token)
{
return context_handle->mech_type->gm_ops
->gss_verify_mic(context_handle,
message,
mic_token);
}
/*
* This function is called from both the client and server code.
* Each makes guarantees about how much "slack" space is available
* for the underlying function in "buf"'s head and tail while
* performing the wrap.
*
* The client and server code allocate RPC_MAX_AUTH_SIZE extra
* space in both the head and tail which is available for use by
* the wrap function.
*
* Underlying functions should verify they do not use more than
* RPC_MAX_AUTH_SIZE of extra space in either the head or tail
* when performing the wrap.
*/
u32
gss_wrap(struct gss_ctx *ctx_id,
int offset,
struct xdr_buf *buf,
struct page **inpages)
{
return ctx_id->mech_type->gm_ops
->gss_wrap(ctx_id, offset, buf, inpages);
}
u32
gss_unwrap(struct gss_ctx *ctx_id,
int offset,
struct xdr_buf *buf)
{
return ctx_id->mech_type->gm_ops
->gss_unwrap(ctx_id, offset, buf);
}
/* gss_delete_sec_context: free all resources associated with context_handle.
* Note this differs from the RFC 2744-specified prototype in that we don't
* bother returning an output token, since it would never be used anyway. */
u32
gss_delete_sec_context(struct gss_ctx **context_handle)
{
dprintk("RPC: gss_delete_sec_context deleting %p\n",
*context_handle);
if (!*context_handle)
return GSS_S_NO_CONTEXT;
if ((*context_handle)->internal_ctx_id)
(*context_handle)->mech_type->gm_ops
->gss_delete_sec_context((*context_handle)
->internal_ctx_id);
gss_mech_put((*context_handle)->mech_type);
kfree(*context_handle);
*context_handle=NULL;
return GSS_S_COMPLETE;
}