Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1080 insertions, 0 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
new file mode 100644
index 0000000..5c8fe3b
--- /dev/null
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -0,0 +1,1080 @@
+/*
+ * Neil Brown <neilb@cse.unsw.edu.au>
+ * J. Bruce Fields <bfields@umich.edu>
+ * Andy Adamson <andros@umich.edu>
+ * Dug Song <dugsong@monkey.org>
+ *
+ * RPCSEC_GSS server authentication.
+ * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078
+ * (gssapi)
+ *
+ * The RPCSEC_GSS involves three stages:
+ *  1/ context creation
+ *  2/ data exchange
+ *  3/ context destruction
+ *
+ * Context creation is handled largely by upcalls to user-space.
+ *  In particular, GSS_Accept_sec_context is handled by an upcall
+ * Data exchange is handled entirely within the kernel
+ *  In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel.
+ * Context destruction is handled in-kernel
+ *  GSS_Delete_sec_context is in-kernel
+ *
+ * Context creation is initiated by a RPCSEC_GSS_INIT request arriving.
+ * The context handle and gss_token are used as a key into the rpcsec_init cache.
+ * The content of this cache includes some of the outputs of GSS_Accept_sec_context,
+ * being major_status, minor_status, context_handle, reply_token.
+ * These are sent back to the client.
+ * Sequence window management is handled by the kernel.  The window size if currently
+ * a compile time constant.
+ *
+ * When user-space is happy that a context is established, it places an entry
+ * in the rpcsec_context cache. The key for this cache is the context_handle.
+ * The content includes:
+ *   uid/gidlist - for determining access rights
+ *   mechanism type
+ *   mechanism specific information, such as a key
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+
+#include <linux/sunrpc/auth_gss.h>
+#include <linux/sunrpc/svcauth.h>
+#include <linux/sunrpc/gss_err.h>
+#include <linux/sunrpc/svcauth.h>
+#include <linux/sunrpc/svcauth_gss.h>
+#include <linux/sunrpc/cache.h>
+
+#ifdef RPC_DEBUG
+# define RPCDBG_FACILITY	RPCDBG_AUTH
+#endif
+
+/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests
+ * into replies.
+ *
+ * Key is context handle (\x if empty) and gss_token.
+ * Content is major_status minor_status (integers) context_handle, reply_token.
+ *
+ */
+
+static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b)
+{
+	return a->len == b->len && 0 == memcmp(a->data, b->data, a->len);
+}
+
+#define	RSI_HASHBITS	6
+#define	RSI_HASHMAX	(1<<RSI_HASHBITS)
+#define	RSI_HASHMASK	(RSI_HASHMAX-1)
+
+struct rsi {
+	struct cache_head	h;
+	struct xdr_netobj	in_handle, in_token;
+	struct xdr_netobj	out_handle, out_token;
+	int			major_status, minor_status;
+};
+
+static struct cache_head *rsi_table[RSI_HASHMAX];
+static struct cache_detail rsi_cache;
+static struct rsi *rsi_lookup(struct rsi *item, int set);
+
+static void rsi_free(struct rsi *rsii)
+{
+	kfree(rsii->in_handle.data);
+	kfree(rsii->in_token.data);
+	kfree(rsii->out_handle.data);
+	kfree(rsii->out_token.data);
+}
+
+static void rsi_put(struct cache_head *item, struct cache_detail *cd)
+{
+	struct rsi *rsii = container_of(item, struct rsi, h);
+	if (cache_put(item, cd)) {
+		rsi_free(rsii);
+		kfree(rsii);
+	}
+}
+
+static inline int rsi_hash(struct rsi *item)
+{
+	return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS)
+	     ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS);
+}
+
+static inline int rsi_match(struct rsi *item, struct rsi *tmp)
+{
+	return netobj_equal(&item->in_handle, &tmp->in_handle)
+		&& netobj_equal(&item->in_token, &tmp->in_token);
+}
+
+static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len)
+{
+	dst->len = len;
+	dst->data = (len ? kmalloc(len, GFP_KERNEL) : NULL);
+	if (dst->data)
+		memcpy(dst->data, src, len);
+	if (len && !dst->data)
+		return -ENOMEM;
+	return 0;
+}
+
+static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src)
+{
+	return dup_to_netobj(dst, src->data, src->len);
+}
+
+static inline void rsi_init(struct rsi *new, struct rsi *item)
+{
+	new->out_handle.data = NULL;
+	new->out_handle.len = 0;
+	new->out_token.data = NULL;
+	new->out_token.len = 0;
+	new->in_handle.len = item->in_handle.len;
+	item->in_handle.len = 0;
+	new->in_token.len = item->in_token.len;
+	item->in_token.len = 0;
+	new->in_handle.data = item->in_handle.data;
+	item->in_handle.data = NULL;
+	new->in_token.data = item->in_token.data;
+	item->in_token.data = NULL;
+}
+
+static inline void rsi_update(struct rsi *new, struct rsi *item)
+{
+	BUG_ON(new->out_handle.data || new->out_token.data);
+	new->out_handle.len = item->out_handle.len;
+	item->out_handle.len = 0;
+	new->out_token.len = item->out_token.len;
+	item->out_token.len = 0;
+	new->out_handle.data = item->out_handle.data;
+	item->out_handle.data = NULL;
+	new->out_token.data = item->out_token.data;
+	item->out_token.data = NULL;
+
+	new->major_status = item->major_status;
+	new->minor_status = item->minor_status;
+}
+
+static void rsi_request(struct cache_detail *cd,
+                       struct cache_head *h,
+                       char **bpp, int *blen)
+{
+	struct rsi *rsii = container_of(h, struct rsi, h);
+
+	qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len);
+	qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len);
+	(*bpp)[-1] = '\n';
+}
+
+
+static int rsi_parse(struct cache_detail *cd,
+                    char *mesg, int mlen)
+{
+	/* context token expiry major minor context token */
+	char *buf = mesg;
+	char *ep;
+	int len;
+	struct rsi rsii, *rsip = NULL;
+	time_t expiry;
+	int status = -EINVAL;
+
+	memset(&rsii, 0, sizeof(rsii));
+	/* handle */
+	len = qword_get(&mesg, buf, mlen);
+	if (len < 0)
+		goto out;
+	status = -ENOMEM;
+	if (dup_to_netobj(&rsii.in_handle, buf, len))
+		goto out;
+
+	/* token */
+	len = qword_get(&mesg, buf, mlen);
+	status = -EINVAL;
+	if (len < 0)
+		goto out;
+	status = -ENOMEM;
+	if (dup_to_netobj(&rsii.in_token, buf, len))
+		goto out;
+
+	rsii.h.flags = 0;
+	/* expiry */
+	expiry = get_expiry(&mesg);
+	status = -EINVAL;
+	if (expiry == 0)
+		goto out;
+
+	/* major/minor */
+	len = qword_get(&mesg, buf, mlen);
+	if (len < 0)
+		goto out;
+	if (len == 0) {
+		goto out;
+	} else {
+		rsii.major_status = simple_strtoul(buf, &ep, 10);
+		if (*ep)
+			goto out;
+		len = qword_get(&mesg, buf, mlen);
+		if (len <= 0)
+			goto out;
+		rsii.minor_status = simple_strtoul(buf, &ep, 10);
+		if (*ep)
+			goto out;
+
+		/* out_handle */
+		len = qword_get(&mesg, buf, mlen);
+		if (len < 0)
+			goto out;
+		status = -ENOMEM;
+		if (dup_to_netobj(&rsii.out_handle, buf, len))
+			goto out;
+
+		/* out_token */
+		len = qword_get(&mesg, buf, mlen);
+		status = -EINVAL;
+		if (len < 0)
+			goto out;
+		status = -ENOMEM;
+		if (dup_to_netobj(&rsii.out_token, buf, len))
+			goto out;
+	}
+	rsii.h.expiry_time = expiry;
+	rsip = rsi_lookup(&rsii, 1);
+	status = 0;
+out:
+	rsi_free(&rsii);
+	if (rsip)
+		rsi_put(&rsip->h, &rsi_cache);
+	return status;
+}
+
+static struct cache_detail rsi_cache = {
+	.hash_size	= RSI_HASHMAX,
+	.hash_table     = rsi_table,
+	.name           = "auth.rpcsec.init",
+	.cache_put      = rsi_put,
+	.cache_request  = rsi_request,
+	.cache_parse    = rsi_parse,
+};
+
+static DefineSimpleCacheLookup(rsi, 0)
+
+/*
+ * The rpcsec_context cache is used to store a context that is
+ * used in data exchange.
+ * The key is a context handle. The content is:
+ *  uid, gidlist, mechanism, service-set, mech-specific-data
+ */
+
+#define	RSC_HASHBITS	10
+#define	RSC_HASHMAX	(1<<RSC_HASHBITS)
+#define	RSC_HASHMASK	(RSC_HASHMAX-1)
+
+#define GSS_SEQ_WIN	128
+
+struct gss_svc_seq_data {
+	/* highest seq number seen so far: */
+	int			sd_max;
+	/* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of
+	 * sd_win is nonzero iff sequence number i has been seen already: */
+	unsigned long		sd_win[GSS_SEQ_WIN/BITS_PER_LONG];
+	spinlock_t		sd_lock;
+};
+
+struct rsc {
+	struct cache_head	h;
+	struct xdr_netobj	handle;
+	struct svc_cred		cred;
+	struct gss_svc_seq_data	seqdata;
+	struct gss_ctx		*mechctx;
+};
+
+static struct cache_head *rsc_table[RSC_HASHMAX];
+static struct cache_detail rsc_cache;
+static struct rsc *rsc_lookup(struct rsc *item, int set);
+
+static void rsc_free(struct rsc *rsci)
+{
+	kfree(rsci->handle.data);
+	if (rsci->mechctx)
+		gss_delete_sec_context(&rsci->mechctx);
+	if (rsci->cred.cr_group_info)
+		put_group_info(rsci->cred.cr_group_info);
+}
+
+static void rsc_put(struct cache_head *item, struct cache_detail *cd)
+{
+	struct rsc *rsci = container_of(item, struct rsc, h);
+
+	if (cache_put(item, cd)) {
+		rsc_free(rsci);
+		kfree(rsci);
+	}
+}
+
+static inline int
+rsc_hash(struct rsc *rsci)
+{
+	return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS);
+}
+
+static inline int
+rsc_match(struct rsc *new, struct rsc *tmp)
+{
+	return netobj_equal(&new->handle, &tmp->handle);
+}
+
+static inline void
+rsc_init(struct rsc *new, struct rsc *tmp)
+{
+	new->handle.len = tmp->handle.len;
+	tmp->handle.len = 0;
+	new->handle.data = tmp->handle.data;
+	tmp->handle.data = NULL;
+	new->mechctx = NULL;
+	new->cred.cr_group_info = NULL;
+}
+
+static inline void
+rsc_update(struct rsc *new, struct rsc *tmp)
+{
+	new->mechctx = tmp->mechctx;
+	tmp->mechctx = NULL;
+	memset(&new->seqdata, 0, sizeof(new->seqdata));
+	spin_lock_init(&new->seqdata.sd_lock);
+	new->cred = tmp->cred;
+	tmp->cred.cr_group_info = NULL;
+}
+
+static int rsc_parse(struct cache_detail *cd,
+		     char *mesg, int mlen)
+{
+	/* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */
+	char *buf = mesg;
+	int len, rv;
+	struct rsc rsci, *rscp = NULL;
+	time_t expiry;
+	int status = -EINVAL;
+
+	memset(&rsci, 0, sizeof(rsci));
+	/* context handle */
+	len = qword_get(&mesg, buf, mlen);
+	if (len < 0) goto out;
+	status = -ENOMEM;
+	if (dup_to_netobj(&rsci.handle, buf, len))
+		goto out;
+
+	rsci.h.flags = 0;
+	/* expiry */
+	expiry = get_expiry(&mesg);
+	status = -EINVAL;
+	if (expiry == 0)
+		goto out;
+
+	/* uid, or NEGATIVE */
+	rv = get_int(&mesg, &rsci.cred.cr_uid);
+	if (rv == -EINVAL)
+		goto out;
+	if (rv == -ENOENT)
+		set_bit(CACHE_NEGATIVE, &rsci.h.flags);
+	else {
+		int N, i;
+		struct gss_api_mech *gm;
+
+		/* gid */
+		if (get_int(&mesg, &rsci.cred.cr_gid))
+			goto out;
+
+		/* number of additional gid's */
+		if (get_int(&mesg, &N))
+			goto out;
+		status = -ENOMEM;
+		rsci.cred.cr_group_info = groups_alloc(N);
+		if (rsci.cred.cr_group_info == NULL)
+			goto out;
+
+		/* gid's */
+		status = -EINVAL;
+		for (i=0; i<N; i++) {
+			gid_t gid;
+			if (get_int(&mesg, &gid))
+				goto out;
+			GROUP_AT(rsci.cred.cr_group_info, i) = gid;
+		}
+
+		/* mech name */
+		len = qword_get(&mesg, buf, mlen);
+		if (len < 0)
+			goto out;
+		gm = gss_mech_get_by_name(buf);
+		status = -EOPNOTSUPP;
+		if (!gm)
+			goto out;
+
+		status = -EINVAL;
+		/* mech-specific data: */
+		len = qword_get(&mesg, buf, mlen);
+		if (len < 0) {
+			gss_mech_put(gm);
+			goto out;
+		}
+		if (gss_import_sec_context(buf, len, gm, &rsci.mechctx)) {
+			gss_mech_put(gm);
+			goto out;
+		}
+		gss_mech_put(gm);
+	}
+	rsci.h.expiry_time = expiry;
+	rscp = rsc_lookup(&rsci, 1);
+	status = 0;
+out:
+	rsc_free(&rsci);
+	if (rscp)
+		rsc_put(&rscp->h, &rsc_cache);
+	return status;
+}
+
+static struct cache_detail rsc_cache = {
+	.hash_size	= RSC_HASHMAX,
+	.hash_table	= rsc_table,
+	.name		= "auth.rpcsec.context",
+	.cache_put	= rsc_put,
+	.cache_parse	= rsc_parse,
+};
+
+static DefineSimpleCacheLookup(rsc, 0);
+
+static struct rsc *
+gss_svc_searchbyctx(struct xdr_netobj *handle)
+{
+	struct rsc rsci;
+	struct rsc *found;
+
+	memset(&rsci, 0, sizeof(rsci));
+	if (dup_to_netobj(&rsci.handle, handle->data, handle->len))
+		return NULL;
+	found = rsc_lookup(&rsci, 0);
+	rsc_free(&rsci);
+	if (!found)
+		return NULL;
+	if (cache_check(&rsc_cache, &found->h, NULL))
+		return NULL;
+	return found;
+}
+
+/* Implements sequence number algorithm as specified in RFC 2203. */
+static int
+gss_check_seq_num(struct rsc *rsci, int seq_num)
+{
+	struct gss_svc_seq_data *sd = &rsci->seqdata;
+
+	spin_lock(&sd->sd_lock);
+	if (seq_num > sd->sd_max) {
+		if (seq_num >= sd->sd_max + GSS_SEQ_WIN) {
+			memset(sd->sd_win,0,sizeof(sd->sd_win));
+			sd->sd_max = seq_num;
+		} else while (sd->sd_max < seq_num) {
+			sd->sd_max++;
+			__clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win);
+		}
+		__set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win);
+		goto ok;
+	} else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) {
+		goto drop;
+	}
+	/* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */
+	if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win))
+		goto drop;
+ok:
+	spin_unlock(&sd->sd_lock);
+	return 1;
+drop:
+	spin_unlock(&sd->sd_lock);
+	return 0;
+}
+
+static inline u32 round_up_to_quad(u32 i)
+{
+	return (i + 3 ) & ~3;
+}
+
+static inline int
+svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o)
+{
+	int l;
+
+	if (argv->iov_len < 4)
+		return -1;
+	o->len = ntohl(svc_getu32(argv));
+	l = round_up_to_quad(o->len);
+	if (argv->iov_len < l)
+		return -1;
+	o->data = argv->iov_base;
+	argv->iov_base += l;
+	argv->iov_len -= l;
+	return 0;
+}
+
+static inline int
+svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
+{
+	u32 *p;
+
+	if (resv->iov_len + 4 > PAGE_SIZE)
+		return -1;
+	svc_putu32(resv, htonl(o->len));
+	p = resv->iov_base + resv->iov_len;
+	resv->iov_len += round_up_to_quad(o->len);
+	if (resv->iov_len > PAGE_SIZE)
+		return -1;
+	memcpy(p, o->data, o->len);
+	memset((u8 *)p + o->len, 0, round_up_to_quad(o->len) - o->len);
+	return 0;
+}
+
+/* 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.
+ */
+static int
+gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
+		  u32 *rpcstart, struct rpc_gss_wire_cred *gc, u32 *authp)
+{
+	struct gss_ctx		*ctx_id = rsci->mechctx;
+	struct xdr_buf		rpchdr;
+	struct xdr_netobj	checksum;
+	u32			flavor = 0;
+	struct kvec		*argv = &rqstp->rq_arg.head[0];
+	struct kvec		iov;
+
+	/* data to compute the checksum over: */
+	iov.iov_base = rpcstart;
+	iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart;
+	xdr_buf_from_iov(&iov, &rpchdr);
+
+	*authp = rpc_autherr_badverf;
+	if (argv->iov_len < 4)
+		return SVC_DENIED;
+	flavor = ntohl(svc_getu32(argv));
+	if (flavor != RPC_AUTH_GSS)
+		return SVC_DENIED;
+	if (svc_safe_getnetobj(argv, &checksum))
+		return SVC_DENIED;
+
+	if (rqstp->rq_deferred) /* skip verification of revisited request */
+		return SVC_OK;
+	if (gss_verify_mic(ctx_id, &rpchdr, &checksum, NULL)
+							!= GSS_S_COMPLETE) {
+		*authp = rpcsec_gsserr_credproblem;
+		return SVC_DENIED;
+	}
+
+	if (gc->gc_seq > MAXSEQ) {
+		dprintk("RPC:      svcauth_gss: discarding request with large sequence number %d\n",
+				gc->gc_seq);
+		*authp = rpcsec_gsserr_ctxproblem;
+		return SVC_DENIED;
+	}
+	if (!gss_check_seq_num(rsci, gc->gc_seq)) {
+		dprintk("RPC:      svcauth_gss: discarding request with old sequence number %d\n",
+				gc->gc_seq);
+		return SVC_DROP;
+	}
+	return SVC_OK;
+}
+
+static int
+gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
+{
+	u32			xdr_seq;
+	u32			maj_stat;
+	struct xdr_buf		verf_data;
+	struct xdr_netobj	mic;
+	u32			*p;
+	struct kvec		iov;
+
+	svc_putu32(rqstp->rq_res.head, htonl(RPC_AUTH_GSS));
+	xdr_seq = htonl(seq);
+
+	iov.iov_base = &xdr_seq;
+	iov.iov_len = sizeof(xdr_seq);
+	xdr_buf_from_iov(&iov, &verf_data);
+	p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
+	mic.data = (u8 *)(p + 1);
+	maj_stat = gss_get_mic(ctx_id, 0, &verf_data, &mic);
+	if (maj_stat != GSS_S_COMPLETE)
+		return -1;
+	*p++ = htonl(mic.len);
+	memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
+	p += XDR_QUADLEN(mic.len);
+	if (!xdr_ressize_check(rqstp, p))
+		return -1;
+	return 0;
+}
+
+struct gss_domain {
+	struct auth_domain	h;
+	u32			pseudoflavor;
+};
+
+static struct auth_domain *
+find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
+{
+	char *name;
+
+	name = gss_service_to_auth_domain_name(ctx->mech_type, svc);
+	if (!name)
+		return NULL;
+	return auth_domain_find(name);
+}
+
+int
+svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
+{
+	struct gss_domain	*new;
+	struct auth_domain	*test;
+	int			stat = -ENOMEM;
+
+	new = kmalloc(sizeof(*new), GFP_KERNEL);
+	if (!new)
+		goto out;
+	cache_init(&new->h.h);
+	new->h.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
+	if (!new->h.name)
+		goto out_free_dom;
+	strcpy(new->h.name, name);
+	new->h.flavour = RPC_AUTH_GSS;
+	new->pseudoflavor = pseudoflavor;
+	new->h.h.expiry_time = NEVER;
+
+	test = auth_domain_lookup(&new->h, 1);
+	if (test == &new->h) {
+		BUG_ON(atomic_dec_and_test(&new->h.h.refcnt));
+	} else { /* XXX Duplicate registration? */
+		auth_domain_put(&new->h);
+		goto out;
+	}
+	return 0;
+
+out_free_dom:
+	kfree(new);
+out:
+	return stat;
+}
+
+EXPORT_SYMBOL(svcauth_gss_register_pseudoflavor);
+
+static inline int
+read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj)
+{
+	u32     raw;
+	int     status;
+
+	status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
+	if (status)
+		return status;
+	*obj = ntohl(raw);
+	return 0;
+}
+
+/* It would be nice if this bit of code could be shared with the client.
+ * Obstacles:
+ *	The client shouldn't malloc(), would have to pass in own memory.
+ *	The server uses base of head iovec as read pointer, while the
+ *	client uses separate pointer. */
+static int
+unwrap_integ_data(struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
+{
+	int stat = -EINVAL;
+	u32 integ_len, maj_stat;
+	struct xdr_netobj mic;
+	struct xdr_buf integ_buf;
+
+	integ_len = ntohl(svc_getu32(&buf->head[0]));
+	if (integ_len & 3)
+		goto out;
+	if (integ_len > buf->len)
+		goto out;
+	if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len))
+		BUG();
+	/* copy out mic... */
+	if (read_u32_from_xdr_buf(buf, integ_len, &mic.len))
+		BUG();
+	if (mic.len > RPC_MAX_AUTH_SIZE)
+		goto out;
+	mic.data = kmalloc(mic.len, GFP_KERNEL);
+	if (!mic.data)
+		goto out;
+	if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len))
+		goto out;
+	maj_stat = gss_verify_mic(ctx, &integ_buf, &mic, NULL);
+	if (maj_stat != GSS_S_COMPLETE)
+		goto out;
+	if (ntohl(svc_getu32(&buf->head[0])) != seq)
+		goto out;
+	stat = 0;
+out:
+	return stat;
+}
+
+struct gss_svc_data {
+	/* decoded gss client cred: */
+	struct rpc_gss_wire_cred	clcred;
+	/* pointer to the beginning of the procedure-specific results,
+	 * which may be encrypted/checksummed in svcauth_gss_release: */
+	u32				*body_start;
+	struct rsc			*rsci;
+};
+
+static int
+svcauth_gss_set_client(struct svc_rqst *rqstp)
+{
+	struct gss_svc_data *svcdata = rqstp->rq_auth_data;
+	struct rsc *rsci = svcdata->rsci;
+	struct rpc_gss_wire_cred *gc = &svcdata->clcred;
+
+	rqstp->rq_client = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
+	if (rqstp->rq_client == NULL)
+		return SVC_DENIED;
+	return SVC_OK;
+}
+
+/*
+ * Accept an rpcsec packet.
+ * If context establishment, punt to user space
+ * If data exchange, verify/decrypt
+ * If context destruction, handle here
+ * In the context establishment and destruction case we encode
+ * response here and return SVC_COMPLETE.
+ */
+static int
+svcauth_gss_accept(struct svc_rqst *rqstp, u32 *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;
+	u32		*rpcstart;
+	u32		*reject_stat = resv->iov_base + resv->iov_len;
+	int		ret;
+
+	dprintk("RPC:      svcauth_gss: argv->iov_len = %zd\n",argv->iov_len);
+
+	*authp = rpc_autherr_badcred;
+	if (!svcdata)
+		svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
+	if (!svcdata)
+		goto auth_err;
+	rqstp->rq_auth_data = svcdata;
+	svcdata->body_start = NULL;
+	svcdata->rsci = NULL;
+	gc = &svcdata->clcred;
+
+	/* start of rpc packet is 7 u32's back from here:
+	 * xid direction rpcversion prog vers proc flavour
+	 */
+	rpcstart = argv->iov_base;
+	rpcstart -= 7;
+
+	/* credential is:
+	 *   version(==1), proc(0,1,2,3), seq, service (1,2,3), handle
+	 * at least 5 u32s, and is preceeded by length, so that makes 6.
+	 */
+
+	if (argv->iov_len < 5 * 4)
+		goto auth_err;
+	crlen = ntohl(svc_getu32(argv));
+	if (ntohl(svc_getu32(argv)) != RPC_GSS_VERSION)
+		goto auth_err;
+	gc->gc_proc = ntohl(svc_getu32(argv));
+	gc->gc_seq = ntohl(svc_getu32(argv));
+	gc->gc_svc = ntohl(svc_getu32(argv));
+	if (svc_safe_getnetobj(argv, &gc->gc_ctx))
+		goto auth_err;
+	if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
+		goto auth_err;
+
+	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 (ntohl(svc_getu32(argv)) != RPC_AUTH_NULL)
+			goto auth_err;
+		if (ntohl(svc_getu32(argv)) != 0)
+			goto auth_err;
+		break;
+	case RPC_GSS_PROC_DATA:
+	case RPC_GSS_PROC_DESTROY:
+		*authp = rpcsec_gsserr_credproblem;
+		rsci = gss_svc_searchbyctx(&gc->gc_ctx);
+		if (!rsci)
+			goto auth_err;
+		switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) {
+		case SVC_OK:
+			break;
+		case SVC_DENIED:
+			goto auth_err;
+		case SVC_DROP:
+			goto drop;
+		}
+		break;
+	default:
+		*authp = rpc_autherr_rejectedcred;
+		goto auth_err;
+	}
+
+	/* 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, 0);
+		rsi_free(&rsikey);
+		if (!rsip) {
+			goto drop;
+		}
+		switch(cache_check(&rsi_cache, &rsip->h, &rqstp->rq_chandle)) {
+		case -EAGAIN:
+			goto drop;
+		case -ENOENT:
+			goto drop;
+		case 0:
+			rsci = gss_svc_searchbyctx(&rsip->out_handle);
+			if (!rsci) {
+				goto drop;
+			}
+			if (gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN))
+				goto drop;
+			if (resv->iov_len + 4 > PAGE_SIZE)
+				goto drop;
+			svc_putu32(resv, rpc_success);
+			if (svc_safe_putnetobj(resv, &rsip->out_handle))
+				goto drop;
+			if (resv->iov_len + 3 * 4 > PAGE_SIZE)
+				goto drop;
+			svc_putu32(resv, htonl(rsip->major_status));
+			svc_putu32(resv, htonl(rsip->minor_status));
+			svc_putu32(resv, htonl(GSS_SEQ_WIN));
+			if (svc_safe_putnetobj(resv, &rsip->out_token))
+				goto drop;
+			rqstp->rq_client = NULL;
+		}
+		goto complete;
+	case RPC_GSS_PROC_DESTROY:
+		set_bit(CACHE_NEGATIVE, &rsci->h.flags);
+		if (resv->iov_len + 4 > PAGE_SIZE)
+			goto drop;
+		svc_putu32(resv, rpc_success);
+		goto complete;
+	case RPC_GSS_PROC_DATA:
+		*authp = rpcsec_gsserr_ctxproblem;
+		if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
+			goto auth_err;
+		rqstp->rq_cred = rsci->cred;
+		get_group_info(rsci->cred.cr_group_info);
+		*authp = rpc_autherr_badcred;
+		switch (gc->gc_svc) {
+		case RPC_GSS_SVC_NONE:
+			break;
+		case RPC_GSS_SVC_INTEGRITY:
+			if (unwrap_integ_data(&rqstp->rq_arg,
+					gc->gc_seq, rsci->mechctx))
+				goto auth_err;
+			/* placeholders for length and seq. number: */
+			svcdata->body_start = resv->iov_base + resv->iov_len;
+			svc_putu32(resv, 0);
+			svc_putu32(resv, 0);
+			break;
+		case RPC_GSS_SVC_PRIVACY:
+			/* currently unsupported */
+		default:
+			goto auth_err;
+		}
+		svcdata->rsci = rsci;
+		cache_get(&rsci->h);
+		ret = SVC_OK;
+		goto out;
+	}
+auth_err:
+	/* Restore write pointer to original value: */
+	xdr_ressize_check(rqstp, reject_stat);
+	ret = SVC_DENIED;
+	goto out;
+complete:
+	ret = SVC_COMPLETE;
+	goto out;
+drop:
+	ret = SVC_DROP;
+out:
+	if (rsci)
+		rsc_put(&rsci->h, &rsc_cache);
+	return ret;
+}
+
+static int
+svcauth_gss_release(struct svc_rqst *rqstp)
+{
+	struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data;
+	struct rpc_gss_wire_cred *gc = &gsd->clcred;
+	struct xdr_buf *resbuf = &rqstp->rq_res;
+	struct xdr_buf integ_buf;
+	struct xdr_netobj mic;
+	struct kvec *resv;
+	u32 *p;
+	int integ_offset, integ_len;
+	int stat = -EINVAL;
+
+	if (gc->gc_proc != RPC_GSS_PROC_DATA)
+		goto out;
+	/* Release can be called twice, but we only wrap once. */
+	if (gsd->body_start == NULL)
+		goto out;
+	/* normally not set till svc_send, but we need it here: */
+	resbuf->len = resbuf->head[0].iov_len
+		+ resbuf->page_len + resbuf->tail[0].iov_len;
+	switch (gc->gc_svc) {
+	case RPC_GSS_SVC_NONE:
+		break;
+	case RPC_GSS_SVC_INTEGRITY:
+		p = gsd->body_start;
+		gsd->body_start = NULL;
+		/* move accept_stat to right place: */
+		memcpy(p, p + 2, 4);
+		/* don't wrap in failure case: */
+		/* Note: counting on not getting here if call was not even
+		 * accepted! */
+		if (*p != rpc_success) {
+			resbuf->head[0].iov_len -= 2 * 4;
+			goto out;
+		}
+		p++;
+		integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base;
+		integ_len = resbuf->len - integ_offset;
+		BUG_ON(integ_len % 4);
+		*p++ = htonl(integ_len);
+		*p++ = htonl(gc->gc_seq);
+		if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset,
+					integ_len))
+			BUG();
+		if (resbuf->page_len == 0
+			&& resbuf->tail[0].iov_len + RPC_MAX_AUTH_SIZE
+				< PAGE_SIZE) {
+			BUG_ON(resbuf->tail[0].iov_len);
+			/* Use head for everything */
+			resv = &resbuf->head[0];
+		} else if (resbuf->tail[0].iov_base == NULL) {
+			/* copied from nfsd4_encode_read */
+			svc_take_page(rqstp);
+			resbuf->tail[0].iov_base = page_address(rqstp
+					->rq_respages[rqstp->rq_resused-1]);
+			rqstp->rq_restailpage = rqstp->rq_resused-1;
+			resbuf->tail[0].iov_len = 0;
+			resv = &resbuf->tail[0];
+		} else {
+			resv = &resbuf->tail[0];
+		}
+		mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
+		if (gss_get_mic(gsd->rsci->mechctx, 0, &integ_buf, &mic))
+			goto out_err;
+		svc_putu32(resv, htonl(mic.len));
+		memset(mic.data + mic.len, 0,
+				round_up_to_quad(mic.len) - mic.len);
+		resv->iov_len += XDR_QUADLEN(mic.len) << 2;
+		/* not strictly required: */
+		resbuf->len += XDR_QUADLEN(mic.len) << 2;
+		BUG_ON(resv->iov_len > PAGE_SIZE);
+		break;
+	case RPC_GSS_SVC_PRIVACY:
+	default:
+		goto out_err;
+	}
+
+out:
+	stat = 0;
+out_err:
+	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;
+	if (gsd->rsci)
+		rsc_put(&gsd->rsci->h, &rsc_cache);
+	gsd->rsci = NULL;
+
+	return stat;
+}
+
+static void
+svcauth_gss_domain_release(struct auth_domain *dom)
+{
+	struct gss_domain *gd = container_of(dom, struct gss_domain, h);
+
+	kfree(dom->name);
+	kfree(gd);
+}
+
+static struct auth_ops svcauthops_gss = {
+	.name		= "rpcsec_gss",
+	.owner		= THIS_MODULE,
+	.flavour	= RPC_AUTH_GSS,
+	.accept		= svcauth_gss_accept,
+	.release	= svcauth_gss_release,
+	.domain_release = svcauth_gss_domain_release,
+	.set_client	= svcauth_gss_set_client,
+};
+
+int
+gss_svc_init(void)
+{
+	int rv = svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss);
+	if (rv == 0) {
+		cache_register(&rsc_cache);
+		cache_register(&rsi_cache);
+	}
+	return rv;
+}
+
+void
+gss_svc_shutdown(void)
+{
+	cache_unregister(&rsc_cache);
+	cache_unregister(&rsi_cache);
+	svc_auth_unregister(RPC_AUTH_GSS);
+}