Skip to content

Commit

Permalink
svcgss: move init code into separate function
Browse files Browse the repository at this point in the history 
We've let svcauth_gss_accept() get much too long and hairy.  The
RPC_GSS_PROC_INIT and RPC_GSS_PROC_CONTINUE_INIT cases share very little
with the other cases, so it's very natural to split them off into a
separate function.

This will also nicely isolate the piece of code we need to parametrize
to authenticating gss-protected NFSv4 callbacks on behalf of the NFS
client.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Neil Brown <neilb@suse.de>
  • Loading branch information
J. Bruce Fields committed Oct 9, 2007
1 parent c175b83 commit 21fcd02
Showing 1 changed file with 77 additions and 67 deletions.
144 changes: 77 additions & 67 deletions net/sunrpc/auth_gss/svcauth_gss.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -631,7 +631,8 @@ svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
return 0;
}

/* Verify the checksum on the header and return SVC_OK on success.
/*
* Verify the checksum on the header and return SVC_OK on success.
* Otherwise, return SVC_DROP (in the case of a bad sequence number)
* or return SVC_DENIED and indicate error in authp.
*/
Expand Down Expand Up @@ -960,6 +961,78 @@ gss_write_init_verf(struct svc_rqst *rqstp, struct rsi *rsip)
return rc;
}

/*
* Having read the cred already and found we're in the context
* initiation case, read the verifier and initiate (or check the results
* of) upcalls to userspace for help with context initiation. If
* the upcall results are available, write the verifier and result.
* Otherwise, drop the request pending an answer to the upcall.
*/
static int svcauth_gss_handle_init(struct svc_rqst *rqstp,
struct rpc_gss_wire_cred *gc, __be32 *authp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
struct xdr_netobj tmpobj;
struct rsi *rsip, rsikey;

/* Read the verifier; should be NULL: */
*authp = rpc_autherr_badverf;
if (argv->iov_len < 2 * 4)
return SVC_DENIED;
if (svc_getnl(argv) != RPC_AUTH_NULL)
return SVC_DENIED;
if (svc_getnl(argv) != 0)
return SVC_DENIED;

/* Martial context handle and token for upcall: */
*authp = rpc_autherr_badcred;
if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
return SVC_DENIED;
memset(&rsikey, 0, sizeof(rsikey));
if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
return SVC_DROP;
*authp = rpc_autherr_badverf;
if (svc_safe_getnetobj(argv, &tmpobj)) {
kfree(rsikey.in_handle.data);
return SVC_DENIED;
}
if (dup_netobj(&rsikey.in_token, &tmpobj)) {
kfree(rsikey.in_handle.data);
return SVC_DROP;
}

/* Perform upcall, or find upcall result: */
rsip = rsi_lookup(&rsikey);
rsi_free(&rsikey);
if (!rsip)
return SVC_DROP;
switch (cache_check(&rsi_cache, &rsip->h, &rqstp->rq_chandle)) {
case -EAGAIN:
case -ETIMEDOUT:
case -ENOENT:
/* No upcall result: */
return SVC_DROP;
case 0:
/* Got an answer to the upcall; use it: */
if (gss_write_init_verf(rqstp, rsip))
return SVC_DROP;
if (resv->iov_len + 4 > PAGE_SIZE)
return SVC_DROP;
svc_putnl(resv, RPC_SUCCESS);
if (svc_safe_putnetobj(resv, &rsip->out_handle))
return SVC_DROP;
if (resv->iov_len + 3 * 4 > PAGE_SIZE)
return SVC_DROP;
svc_putnl(resv, rsip->major_status);
svc_putnl(resv, rsip->minor_status);
svc_putnl(resv, GSS_SEQ_WIN);
if (svc_safe_putnetobj(resv, &rsip->out_token))
return SVC_DROP;
}
return SVC_COMPLETE;
}

/*
* Accept an rpcsec packet.
* If context establishment, punt to user space
Expand All @@ -974,11 +1047,9 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
u32 crlen;
struct xdr_netobj tmpobj;
struct gss_svc_data *svcdata = rqstp->rq_auth_data;
struct rpc_gss_wire_cred *gc;
struct rsc *rsci = NULL;
struct rsi *rsip, rsikey;
__be32 *rpcstart;
__be32 *reject_stat = resv->iov_base + resv->iov_len;
int ret;
Expand Down Expand Up @@ -1023,30 +1094,14 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
goto auth_err;

/*
* We've successfully parsed the credential. Let's check out the
* verifier. An AUTH_NULL verifier is allowed (and required) for
* INIT and CONTINUE_INIT requests. AUTH_RPCSEC_GSS is required for
* PROC_DATA and PROC_DESTROY.
*
* AUTH_NULL verifier is 0 (AUTH_NULL), 0 (length).
* AUTH_RPCSEC_GSS verifier is:
* 6 (AUTH_RPCSEC_GSS), length, checksum.
* checksum is calculated over rpcheader from xid up to here.
*/
*authp = rpc_autherr_badverf;
switch (gc->gc_proc) {
case RPC_GSS_PROC_INIT:
case RPC_GSS_PROC_CONTINUE_INIT:
if (argv->iov_len < 2 * 4)
goto auth_err;
if (svc_getnl(argv) != RPC_AUTH_NULL)
goto auth_err;
if (svc_getnl(argv) != 0)
goto auth_err;
break;
return svcauth_gss_handle_init(rqstp, gc, authp);
case RPC_GSS_PROC_DATA:
case RPC_GSS_PROC_DESTROY:
/* Look up the context, and check the verifier: */
*authp = rpcsec_gsserr_credproblem;
rsci = gss_svc_searchbyctx(&gc->gc_ctx);
if (!rsci)
Expand All @@ -1067,51 +1122,6 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)

/* now act upon the command: */
switch (gc->gc_proc) {
case RPC_GSS_PROC_INIT:
case RPC_GSS_PROC_CONTINUE_INIT:
*authp = rpc_autherr_badcred;
if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0)
goto auth_err;
memset(&rsikey, 0, sizeof(rsikey));
if (dup_netobj(&rsikey.in_handle, &gc->gc_ctx))
goto drop;
*authp = rpc_autherr_badverf;
if (svc_safe_getnetobj(argv, &tmpobj)) {
kfree(rsikey.in_handle.data);
goto auth_err;
}
if (dup_netobj(&rsikey.in_token, &tmpobj)) {
kfree(rsikey.in_handle.data);
goto drop;
}

rsip = rsi_lookup(&rsikey);
rsi_free(&rsikey);
if (!rsip) {
goto drop;
}
switch(cache_check(&rsi_cache, &rsip->h, &rqstp->rq_chandle)) {
case -EAGAIN:
case -ETIMEDOUT:
case -ENOENT:
goto drop;
case 0:
if (gss_write_init_verf(rqstp, rsip))
goto drop;
if (resv->iov_len + 4 > PAGE_SIZE)
goto drop;
svc_putnl(resv, RPC_SUCCESS);
if (svc_safe_putnetobj(resv, &rsip->out_handle))
goto drop;
if (resv->iov_len + 3 * 4 > PAGE_SIZE)
goto drop;
svc_putnl(resv, rsip->major_status);
svc_putnl(resv, rsip->minor_status);
svc_putnl(resv, GSS_SEQ_WIN);
if (svc_safe_putnetobj(resv, &rsip->out_token))
goto drop;
}
goto complete;
case RPC_GSS_PROC_DESTROY:
if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
goto auth_err;
Expand Down Expand Up @@ -1158,7 +1168,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
goto out;
}
auth_err:
/* Restore write pointer to original value: */
/* Restore write pointer to its original value: */
xdr_ressize_check(rqstp, reject_stat);
ret = SVC_DENIED;
goto out;
Expand Down

0 comments on commit 21fcd02

Please sign in to comment.