RPCSEC_GSS: client-side privacy support
Add the code to the client side to handle privacy. This is dead code until
we actually add privacy support to krb5.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index dc95b79..5e48720 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -43,6 +43,7 @@
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/pagemap.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/auth_gss.h>
@@ -975,6 +976,114 @@
return 0;
}
+static void
+priv_release_snd_buf(struct rpc_rqst *rqstp)
+{
+ int i;
+
+ for (i=0; i < rqstp->rq_enc_pages_num; i++)
+ __free_page(rqstp->rq_enc_pages[i]);
+ kfree(rqstp->rq_enc_pages);
+}
+
+static int
+alloc_enc_pages(struct rpc_rqst *rqstp)
+{
+ struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
+ int first, last, i;
+
+ if (snd_buf->page_len == 0) {
+ rqstp->rq_enc_pages_num = 0;
+ return 0;
+ }
+
+ first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
+ last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
+ rqstp->rq_enc_pages_num = last - first + 1 + 1;
+ rqstp->rq_enc_pages
+ = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
+ GFP_NOFS);
+ if (!rqstp->rq_enc_pages)
+ goto out;
+ for (i=0; i < rqstp->rq_enc_pages_num; i++) {
+ rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS);
+ if (rqstp->rq_enc_pages[i] == NULL)
+ goto out_free;
+ }
+ rqstp->rq_release_snd_buf = priv_release_snd_buf;
+ return 0;
+out_free:
+ for (i--; i >= 0; i--) {
+ __free_page(rqstp->rq_enc_pages[i]);
+ }
+out:
+ return -EAGAIN;
+}
+
+static inline int
+gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
+ kxdrproc_t encode, struct rpc_rqst *rqstp, u32 *p, void *obj)
+{
+ struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
+ u32 offset;
+ u32 maj_stat;
+ int status;
+ u32 *opaque_len;
+ struct page **inpages;
+ int first;
+ int pad;
+ struct kvec *iov;
+ char *tmp;
+
+ opaque_len = p++;
+ offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
+ *p++ = htonl(rqstp->rq_seqno);
+
+ status = encode(rqstp, p, obj);
+ if (status)
+ return status;
+
+ status = alloc_enc_pages(rqstp);
+ if (status)
+ return status;
+ first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
+ inpages = snd_buf->pages + first;
+ snd_buf->pages = rqstp->rq_enc_pages;
+ snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
+ /* Give the tail its own page, in case we need extra space in the
+ * head when wrapping: */
+ if (snd_buf->page_len || snd_buf->tail[0].iov_len) {
+ tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
+ memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len);
+ snd_buf->tail[0].iov_base = tmp;
+ }
+ maj_stat = gss_wrap(ctx->gc_gss_ctx, GSS_C_QOP_DEFAULT, offset,
+ snd_buf, inpages);
+ /* RPC_SLACK_SPACE should prevent this ever happening: */
+ BUG_ON(snd_buf->len > snd_buf->buflen);
+ status = -EIO;
+ /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
+ * done anyway, so it's safe to put the request on the wire: */
+ if (maj_stat == GSS_S_CONTEXT_EXPIRED)
+ cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+ else if (maj_stat)
+ return status;
+
+ *opaque_len = htonl(snd_buf->len - offset);
+ /* guess whether we're in the head or the tail: */
+ if (snd_buf->page_len || snd_buf->tail[0].iov_len)
+ iov = snd_buf->tail;
+ else
+ iov = snd_buf->head;
+ p = iov->iov_base + iov->iov_len;
+ pad = 3 - ((snd_buf->len - offset - 1) & 3);
+ memset(p, 0, pad);
+ iov->iov_len += pad;
+ snd_buf->len += pad;
+
+ return 0;
+}
+
static int
gss_wrap_req(struct rpc_task *task,
kxdrproc_t encode, void *rqstp, u32 *p, void *obj)
@@ -1002,6 +1111,8 @@
rqstp, p, obj);
break;
case RPC_GSS_SVC_PRIVACY:
+ status = gss_wrap_req_priv(cred, ctx, encode,
+ rqstp, p, obj);
break;
}
out:
@@ -1048,6 +1159,36 @@
return 0;
}
+static inline int
+gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
+ struct rpc_rqst *rqstp, u32 **p)
+{
+ struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
+ u32 offset;
+ u32 opaque_len;
+ u32 maj_stat;
+ int status = -EIO;
+
+ opaque_len = ntohl(*(*p)++);
+ offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
+ if (offset + opaque_len > rcv_buf->len)
+ return status;
+ /* remove padding: */
+ rcv_buf->len = offset + opaque_len;
+
+ maj_stat = gss_unwrap(ctx->gc_gss_ctx, NULL,
+ offset, rcv_buf);
+ if (maj_stat == GSS_S_CONTEXT_EXPIRED)
+ cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+ if (maj_stat != GSS_S_COMPLETE)
+ return status;
+ if (ntohl(*(*p)++) != rqstp->rq_seqno)
+ return status;
+
+ return 0;
+}
+
+
static int
gss_unwrap_resp(struct rpc_task *task,
kxdrproc_t decode, void *rqstp, u32 *p, void *obj)
@@ -1057,6 +1198,8 @@
gc_base);
struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
u32 *savedp = p;
+ struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head;
+ int savedlen = head->iov_len;
int status = -EIO;
if (ctx->gc_proc != RPC_GSS_PROC_DATA)
@@ -1070,10 +1213,14 @@
goto out;
break;
case RPC_GSS_SVC_PRIVACY:
+ status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p);
+ if (status)
+ goto out;
break;
}
/* take into account extra slack for integrity and privacy cases: */
- task->tk_auth->au_rslack = task->tk_auth->au_verfsize + (p - savedp);
+ task->tk_auth->au_rslack = task->tk_auth->au_verfsize + (p - savedp)
+ + (savedlen - head->iov_len);
out_decode:
status = decode(rqstp, p, obj);
out: