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Diffstat (limited to 'net/sunrpc/auth_gss/svcauth_gss.c')
-rw-r--r--net/sunrpc/auth_gss/svcauth_gss.c1080
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 00000000000..5c8fe3bfc49
--- /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);
+}