/* * linux/net/sunrpc/auth_gss/auth_gss.c * * RPCSEC_GSS client authentication. * * Copyright (c) 2000 The Regents of the University of Michigan. * All rights reserved. * * Dug Song * Andy Adamson * * 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. * * $Id$ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static const struct rpc_authops authgss_ops; static const struct rpc_credops gss_credops; #ifdef RPC_DEBUG # define RPCDBG_FACILITY RPCDBG_AUTH #endif #define NFS_NGROUPS 16 #define GSS_CRED_EXPIRE (60 * HZ) /* XXX: reasonable? */ #define GSS_CRED_SLACK 1024 /* XXX: unused */ /* length of a krb5 verifier (48), plus data added before arguments when * using integrity (two 4-byte integers): */ #define GSS_VERF_SLACK 100 /* XXX this define must match the gssd define * as it is passed to gssd to signal the use of * machine creds should be part of the shared rpc interface */ #define CA_RUN_AS_MACHINE 0x00000200 /* dump the buffer in `emacs-hexl' style */ #define isprint(c) ((c > 0x1f) && (c < 0x7f)) static DEFINE_RWLOCK(gss_ctx_lock); struct gss_auth { struct rpc_auth rpc_auth; struct gss_api_mech *mech; enum rpc_gss_svc service; struct rpc_clnt *client; struct dentry *dentry; }; static void gss_destroy_ctx(struct gss_cl_ctx *); static struct rpc_pipe_ops gss_upcall_ops; static inline struct gss_cl_ctx * gss_get_ctx(struct gss_cl_ctx *ctx) { atomic_inc(&ctx->count); return ctx; } static inline void gss_put_ctx(struct gss_cl_ctx *ctx) { if (atomic_dec_and_test(&ctx->count)) gss_destroy_ctx(ctx); } static void gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) { struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *old; write_lock(&gss_ctx_lock); old = gss_cred->gc_ctx; gss_cred->gc_ctx = ctx; set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); write_unlock(&gss_ctx_lock); if (old) gss_put_ctx(old); } static int gss_cred_is_uptodate_ctx(struct rpc_cred *cred) { struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); int res = 0; read_lock(&gss_ctx_lock); if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) && gss_cred->gc_ctx) res = 1; read_unlock(&gss_ctx_lock); return res; } static const void * simple_get_bytes(const void *p, const void *end, void *res, size_t len) { const void *q = (const void *)((const char *)p + len); if (unlikely(q > end || q < p)) return ERR_PTR(-EFAULT); memcpy(res, p, len); return q; } static inline const void * simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) { const void *q; unsigned int len; p = simple_get_bytes(p, end, &len, sizeof(len)); if (IS_ERR(p)) return p; q = (const void *)((const char *)p + len); if (unlikely(q > end || q < p)) return ERR_PTR(-EFAULT); dest->data = kmemdup(p, len, GFP_KERNEL); if (unlikely(dest->data == NULL)) return ERR_PTR(-ENOMEM); dest->len = len; return q; } static struct gss_cl_ctx * gss_cred_get_ctx(struct rpc_cred *cred) { struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *ctx = NULL; read_lock(&gss_ctx_lock); if (gss_cred->gc_ctx) ctx = gss_get_ctx(gss_cred->gc_ctx); read_unlock(&gss_ctx_lock); return ctx; } static struct gss_cl_ctx * gss_alloc_context(void) { struct gss_cl_ctx *ctx; ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); if (ctx != NULL) { ctx->gc_proc = RPC_GSS_PROC_DATA; ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ spin_lock_init(&ctx->gc_seq_lock); atomic_set(&ctx->count,1); } return ctx; } #define GSSD_MIN_TIMEOUT (60 * 60) static const void * gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) { const void *q; unsigned int seclen; unsigned int timeout; u32 window_size; int ret; /* First unsigned int gives the lifetime (in seconds) of the cred */ p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); if (IS_ERR(p)) goto err; if (timeout == 0) timeout = GSSD_MIN_TIMEOUT; ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; /* Sequence number window. Determines the maximum number of simultaneous requests */ p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); if (IS_ERR(p)) goto err; ctx->gc_win = window_size; /* gssd signals an error by passing ctx->gc_win = 0: */ if (ctx->gc_win == 0) { /* in which case, p points to an error code which we ignore */ p = ERR_PTR(-EACCES); goto err; } /* copy the opaque wire context */ p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); if (IS_ERR(p)) goto err; /* import the opaque security context */ p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); if (IS_ERR(p)) goto err; q = (const void *)((const char *)p + seclen); if (unlikely(q > end || q < p)) { p = ERR_PTR(-EFAULT); goto err; } ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx); if (ret < 0) { p = ERR_PTR(ret); goto err; } return q; err: dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); return p; } struct gss_upcall_msg { atomic_t count; uid_t uid; struct rpc_pipe_msg msg; struct list_head list; struct gss_auth *auth; struct rpc_wait_queue rpc_waitqueue; wait_queue_head_t waitqueue; struct gss_cl_ctx *ctx; }; static void gss_release_msg(struct gss_upcall_msg *gss_msg) { if (!atomic_dec_and_test(&gss_msg->count)) return; BUG_ON(!list_empty(&gss_msg->list)); if (gss_msg->ctx != NULL) gss_put_ctx(gss_msg->ctx); kfree(gss_msg); } static struct gss_upcall_msg * __gss_find_upcall(struct rpc_inode *rpci, uid_t uid) { struct gss_upcall_msg *pos; list_for_each_entry(pos, &rpci->in_downcall, list) { if (pos->uid != uid) continue; atomic_inc(&pos->count); dprintk("RPC: gss_find_upcall found msg %p\n", pos); return pos; } dprintk("RPC: gss_find_upcall found nothing\n"); return NULL; } /* Try to add a upcall to the pipefs queue. * If an upcall owned by our uid already exists, then we return a reference * to that upcall instead of adding the new upcall. */ static inline struct gss_upcall_msg * gss_add_msg(struct gss_auth *gss_auth, struct gss_upcall_msg *gss_msg) { struct inode *inode = gss_auth->dentry->d_inode; struct rpc_inode *rpci = RPC_I(inode); struct gss_upcall_msg *old; spin_lock(&inode->i_lock); old = __gss_find_upcall(rpci, gss_msg->uid); if (old == NULL) { atomic_inc(&gss_msg->count); list_add(&gss_msg->list, &rpci->in_downcall); } else gss_msg = old; spin_unlock(&inode->i_lock); return gss_msg; } static void __gss_unhash_msg(struct gss_upcall_msg *gss_msg) { list_del_init(&gss_msg->list); rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); wake_up_all(&gss_msg->waitqueue); atomic_dec(&gss_msg->count); } static void gss_unhash_msg(struct gss_upcall_msg *gss_msg) { struct gss_auth *gss_auth = gss_msg->auth; struct inode *inode = gss_auth->dentry->d_inode; if (list_empty(&gss_msg->list)) return; spin_lock(&inode->i_lock); if (!list_empty(&gss_msg->list)) __gss_unhash_msg(gss_msg); spin_unlock(&inode->i_lock); } static void gss_upcall_callback(struct rpc_task *task) { struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred, struct gss_cred, gc_base); struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; struct inode *inode = gss_msg->auth->dentry->d_inode; if (gss_msg->ctx) gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_get_ctx(gss_msg->ctx)); else task->tk_status = gss_msg->msg.errno; spin_lock(&inode->i_lock); gss_cred->gc_upcall = NULL; rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); spin_unlock(&inode->i_lock); gss_release_msg(gss_msg); } static inline struct gss_upcall_msg * gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid) { struct gss_upcall_msg *gss_msg; gss_msg = kzalloc(sizeof(*gss_msg), GFP_KERNEL); if (gss_msg != NULL) { INIT_LIST_HEAD(&gss_msg->list); rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); init_waitqueue_head(&gss_msg->waitqueue); atomic_set(&gss_msg->count, 1); gss_msg->msg.data = &gss_msg->uid; gss_msg->msg.len = sizeof(gss_msg->uid); gss_msg->uid = uid; gss_msg->auth = gss_auth; } return gss_msg; } static struct gss_upcall_msg * gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) { struct gss_upcall_msg *gss_new, *gss_msg; gss_new = gss_alloc_msg(gss_auth, cred->cr_uid); if (gss_new == NULL) return ERR_PTR(-ENOMEM); gss_msg = gss_add_msg(gss_auth, gss_new); if (gss_msg == gss_new) { int res = rpc_queue_upcall(gss_auth->dentry->d_inode, &gss_new->msg); if (res) { gss_unhash_msg(gss_new); gss_msg = ERR_PTR(res); } } else gss_release_msg(gss_new); return gss_msg; } static inline int gss_refresh_upcall(struct rpc_task *task) { struct rpc_cred *cred = task->tk_msg.rpc_cred; struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_upcall_msg *gss_msg; struct inode *inode = gss_auth->dentry->d_inode; int err = 0; dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, cred->cr_uid); gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); if (IS_ERR(gss_msg)) { err = PTR_ERR(gss_msg); goto out; } spin_lock(&inode->i_lock); if (gss_cred->gc_upcall != NULL) rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL, NULL); else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { task->tk_timeout = 0; gss_cred->gc_upcall = gss_msg; /* gss_upcall_callback will release the reference to gss_upcall_msg */ atomic_inc(&gss_msg->count); rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback, NULL); } else err = gss_msg->msg.errno; spin_unlock(&inode->i_lock); gss_release_msg(gss_msg); out: dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", task->tk_pid, cred->cr_uid, err); return err; } static inline int gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) { struct inode *inode = gss_auth->dentry->d_inode; struct rpc_cred *cred = &gss_cred->gc_base; struct gss_upcall_msg *gss_msg; DEFINE_WAIT(wait); int err = 0; dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); if (IS_ERR(gss_msg)) { err = PTR_ERR(gss_msg); goto out; } for (;;) { prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); spin_lock(&inode->i_lock); if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { spin_unlock(&inode->i_lock); break; } spin_unlock(&inode->i_lock); if (signalled()) { err = -ERESTARTSYS; goto out_intr; } schedule(); } if (gss_msg->ctx) gss_cred_set_ctx(cred, gss_get_ctx(gss_msg->ctx)); else err = gss_msg->msg.errno; out_intr: finish_wait(&gss_msg->waitqueue, &wait); gss_release_msg(gss_msg); out: dprintk("RPC: gss_create_upcall for uid %u result %d\n", cred->cr_uid, err); return err; } static ssize_t gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, char __user *dst, size_t buflen) { char *data = (char *)msg->data + msg->copied; ssize_t mlen = msg->len; ssize_t left; if (mlen > buflen) mlen = buflen; left = copy_to_user(dst, data, mlen); if (left < 0) { msg->errno = left; return left; } mlen -= left; msg->copied += mlen; msg->errno = 0; return mlen; } #define MSG_BUF_MAXSIZE 1024 static ssize_t gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) { const void *p, *end; void *buf; struct rpc_clnt *clnt; struct gss_upcall_msg *gss_msg; struct inode *inode = filp->f_path.dentry->d_inode; struct gss_cl_ctx *ctx; uid_t uid; ssize_t err = -EFBIG; if (mlen > MSG_BUF_MAXSIZE) goto out; err = -ENOMEM; buf = kmalloc(mlen, GFP_KERNEL); if (!buf) goto out; clnt = RPC_I(inode)->private; err = -EFAULT; if (copy_from_user(buf, src, mlen)) goto err; end = (const void *)((char *)buf + mlen); p = simple_get_bytes(buf, end, &uid, sizeof(uid)); if (IS_ERR(p)) { err = PTR_ERR(p); goto err; } err = -ENOMEM; ctx = gss_alloc_context(); if (ctx == NULL) goto err; err = -ENOENT; /* Find a matching upcall */ spin_lock(&inode->i_lock); gss_msg = __gss_find_upcall(RPC_I(inode), uid); if (gss_msg == NULL) { spin_unlock(&inode->i_lock); goto err_put_ctx; } list_del_init(&gss_msg->list); spin_unlock(&inode->i_lock); p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); if (IS_ERR(p)) { err = PTR_ERR(p); gss_msg->msg.errno = (err == -EACCES) ? -EACCES : -EAGAIN; goto err_release_msg; } gss_msg->ctx = gss_get_ctx(ctx); err = mlen; err_release_msg: spin_lock(&inode->i_lock); __gss_unhash_msg(gss_msg); spin_unlock(&inode->i_lock); gss_release_msg(gss_msg); err_put_ctx: gss_put_ctx(ctx); err: kfree(buf); out: dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); return err; } static void gss_pipe_release(struct inode *inode) { struct rpc_inode *rpci = RPC_I(inode); struct gss_upcall_msg *gss_msg; spin_lock(&inode->i_lock); while (!list_empty(&rpci->in_downcall)) { gss_msg = list_entry(rpci->in_downcall.next, struct gss_upcall_msg, list); gss_msg->msg.errno = -EPIPE; atomic_inc(&gss_msg->count); __gss_unhash_msg(gss_msg); spin_unlock(&inode->i_lock); gss_release_msg(gss_msg); spin_lock(&inode->i_lock); } spin_unlock(&inode->i_lock); } static void gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) { struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); static unsigned long ratelimit; if (msg->errno < 0) { dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", gss_msg); atomic_inc(&gss_msg->count); gss_unhash_msg(gss_msg); if (msg->errno == -ETIMEDOUT) { unsigned long now = jiffies; if (time_after(now, ratelimit)) { printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" "Please check user daemon is running!\n"); ratelimit = now + 15*HZ; } } gss_release_msg(gss_msg); } } /* * NOTE: we have the opportunity to use different * parameters based on the input flavor (which must be a pseudoflavor) */ static struct rpc_auth * gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) { struct gss_auth *gss_auth; struct rpc_auth * auth; int err = -ENOMEM; /* XXX? */ dprintk("RPC: creating GSS authenticator for client %p\n", clnt); if (!try_module_get(THIS_MODULE)) return ERR_PTR(err); if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) goto out_dec; gss_auth->client = clnt; err = -EINVAL; gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); if (!gss_auth->mech) { printk(KERN_WARNING "%s: Pseudoflavor %d not found!", __FUNCTION__, flavor); goto err_free; } gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); if (gss_auth->service == 0) goto err_put_mech; auth = &gss_auth->rpc_auth; auth->au_cslack = GSS_CRED_SLACK >> 2; auth->au_rslack = GSS_VERF_SLACK >> 2; auth->au_ops = &authgss_ops; auth->au_flavor = flavor; atomic_set(&auth->au_count, 1); gss_auth->dentry = rpc_mkpipe(clnt->cl_dentry, gss_auth->mech->gm_name, clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN); if (IS_ERR(gss_auth->dentry)) { err = PTR_ERR(gss_auth->dentry); goto err_put_mech; } err = rpcauth_init_credcache(auth, GSS_CRED_EXPIRE); if (err) goto err_unlink_pipe; return auth; err_unlink_pipe: rpc_unlink(gss_auth->dentry); err_put_mech: gss_mech_put(gss_auth->mech); err_free: kfree(gss_auth); out_dec: module_put(THIS_MODULE); return ERR_PTR(err); } static void gss_destroy(struct rpc_auth *auth) { struct gss_auth *gss_auth; dprintk("RPC: destroying GSS authenticator %p flavor %d\n", auth, auth->au_flavor); rpcauth_destroy_credcache(auth); gss_auth = container_of(auth, struct gss_auth, rpc_auth); rpc_unlink(gss_auth->dentry); gss_auth->dentry = NULL; gss_mech_put(gss_auth->mech); kfree(gss_auth); module_put(THIS_MODULE); } /* gss_destroy_cred (and gss_destroy_ctx) are used to clean up after failure * to create a new cred or context, so they check that things have been * allocated before freeing them. */ static void gss_destroy_ctx(struct gss_cl_ctx *ctx) { dprintk("RPC: gss_destroy_ctx\n"); if (ctx->gc_gss_ctx) gss_delete_sec_context(&ctx->gc_gss_ctx); kfree(ctx->gc_wire_ctx.data); kfree(ctx); } static void gss_free_cred(struct gss_cred *gss_cred) { dprintk("RPC: gss_free_cred %p\n", gss_cred); if (gss_cred->gc_ctx) gss_put_ctx(gss_cred->gc_ctx); kfree(gss_cred); } static void gss_free_cred_callback(struct rcu_head *head) { struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); gss_free_cred(gss_cred); } static void gss_destroy_cred(struct rpc_cred *cred) { call_rcu(&cred->cr_rcu, gss_free_cred_callback); } /* * Lookup RPCSEC_GSS cred for the current process */ static struct rpc_cred * gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) { return rpcauth_lookup_credcache(auth, acred, flags); } static struct rpc_cred * gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) { struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); struct gss_cred *cred = NULL; int err = -ENOMEM; dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", acred->uid, auth->au_flavor); if (!(cred = kzalloc(sizeof(*cred), GFP_KERNEL))) goto out_err; rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); /* * Note: in order to force a call to call_refresh(), we deliberately * fail to flag the credential as RPCAUTH_CRED_UPTODATE. */ cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; cred->gc_service = gss_auth->service; return &cred->gc_base; out_err: dprintk("RPC: gss_create_cred failed with error %d\n", err); return ERR_PTR(err); } static int gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) { struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); int err; do { err = gss_create_upcall(gss_auth, gss_cred); } while (err == -EAGAIN); return err; } static int gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) { struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); /* * If the searchflags have set RPCAUTH_LOOKUP_NEW, then * we don't really care if the credential has expired or not, * since the caller should be prepared to reinitialise it. */ if ((flags & RPCAUTH_LOOKUP_NEW) && test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) goto out; /* Don't match with creds that have expired. */ if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) return 0; out: return (rc->cr_uid == acred->uid); } /* * Marshal credentials. * Maybe we should keep a cached credential for performance reasons. */ static __be32 * gss_marshal(struct rpc_task *task, __be32 *p) { struct rpc_cred *cred = task->tk_msg.rpc_cred; struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); __be32 *cred_len; struct rpc_rqst *req = task->tk_rqstp; u32 maj_stat = 0; struct xdr_netobj mic; struct kvec iov; struct xdr_buf verf_buf; dprintk("RPC: %5u gss_marshal\n", task->tk_pid); *p++ = htonl(RPC_AUTH_GSS); cred_len = p++; spin_lock(&ctx->gc_seq_lock); req->rq_seqno = ctx->gc_seq++; spin_unlock(&ctx->gc_seq_lock); *p++ = htonl((u32) RPC_GSS_VERSION); *p++ = htonl((u32) ctx->gc_proc); *p++ = htonl((u32) req->rq_seqno); *p++ = htonl((u32) gss_cred->gc_service); p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); *cred_len = htonl((p - (cred_len + 1)) << 2); /* We compute the checksum for the verifier over the xdr-encoded bytes * starting with the xid and ending at the end of the credential: */ iov.iov_base = xprt_skip_transport_header(task->tk_xprt, req->rq_snd_buf.head[0].iov_base); iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; xdr_buf_from_iov(&iov, &verf_buf); /* set verifier flavor*/ *p++ = htonl(RPC_AUTH_GSS); mic.data = (u8 *)(p + 1); maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); if (maj_stat == GSS_S_CONTEXT_EXPIRED) { clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); } else if (maj_stat != 0) { printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); goto out_put_ctx; } p = xdr_encode_opaque(p, NULL, mic.len); gss_put_ctx(ctx); return p; out_put_ctx: gss_put_ctx(ctx); return NULL; } /* * Refresh credentials. XXX - finish */ static int gss_refresh(struct rpc_task *task) { if (!gss_cred_is_uptodate_ctx(task->tk_msg.rpc_cred)) return gss_refresh_upcall(task); return 0; } static __be32 * gss_validate(struct rpc_task *task, __be32 *p) { struct rpc_cred *cred = task->tk_msg.rpc_cred; struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); __be32 seq; struct kvec iov; struct xdr_buf verf_buf; struct xdr_netobj mic; u32 flav,len; u32 maj_stat; dprintk("RPC: %5u gss_validate\n", task->tk_pid); flav = ntohl(*p++); if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) goto out_bad; if (flav != RPC_AUTH_GSS) goto out_bad; seq = htonl(task->tk_rqstp->rq_seqno); iov.iov_base = &seq; iov.iov_len = sizeof(seq); xdr_buf_from_iov(&iov, &verf_buf); mic.data = (u8 *)p; mic.len = len; maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); if (maj_stat == GSS_S_CONTEXT_EXPIRED) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); if (maj_stat) goto out_bad; /* We leave it to unwrap to calculate au_rslack. For now we just * calculate the length of the verifier: */ task->tk_auth->au_verfsize = XDR_QUADLEN(len) + 2; gss_put_ctx(ctx); dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", task->tk_pid); return p + XDR_QUADLEN(len); out_bad: gss_put_ctx(ctx); dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); return NULL; } static inline int gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) { struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; struct xdr_buf integ_buf; __be32 *integ_len = NULL; struct xdr_netobj mic; u32 offset; __be32 *q; struct kvec *iov; u32 maj_stat = 0; int status = -EIO; integ_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; if (xdr_buf_subsegment(snd_buf, &integ_buf, offset, snd_buf->len - offset)) return status; *integ_len = htonl(integ_buf.len); /* 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; mic.data = (u8 *)(p + 1); maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); status = -EIO; /* XXX? */ if (maj_stat == GSS_S_CONTEXT_EXPIRED) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); else if (maj_stat) return status; q = xdr_encode_opaque(p, NULL, mic.len); offset = (u8 *)q - (u8 *)p; iov->iov_len += offset; snd_buf->len += offset; 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, __be32 *p, void *obj) { struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; u32 offset; u32 maj_stat; int status; __be32 *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, 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) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 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, __be32 *p, void *obj) { struct rpc_cred *cred = task->tk_msg.rpc_cred; struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); int status = -EIO; dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); if (ctx->gc_proc != RPC_GSS_PROC_DATA) { /* The spec seems a little ambiguous here, but I think that not * wrapping context destruction requests makes the most sense. */ status = encode(rqstp, p, obj); goto out; } switch (gss_cred->gc_service) { case RPC_GSS_SVC_NONE: status = encode(rqstp, p, obj); break; case RPC_GSS_SVC_INTEGRITY: status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj); break; case RPC_GSS_SVC_PRIVACY: status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj); break; } out: gss_put_ctx(ctx); dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); return status; } static inline int gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, struct rpc_rqst *rqstp, __be32 **p) { struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; struct xdr_buf integ_buf; struct xdr_netobj mic; u32 data_offset, mic_offset; u32 integ_len; u32 maj_stat; int status = -EIO; integ_len = ntohl(*(*p)++); if (integ_len & 3) return status; data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; mic_offset = integ_len + data_offset; if (mic_offset > rcv_buf->len) return status; if (ntohl(*(*p)++) != rqstp->rq_seqno) return status; if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, mic_offset - data_offset)) return status; if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) return status; maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); if (maj_stat == GSS_S_CONTEXT_EXPIRED) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); if (maj_stat != GSS_S_COMPLETE) return status; return 0; } static inline int gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, struct rpc_rqst *rqstp, __be32 **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, offset, rcv_buf); if (maj_stat == GSS_S_CONTEXT_EXPIRED) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 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, __be32 *p, void *obj) { struct rpc_cred *cred = task->tk_msg.rpc_cred; struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); __be32 *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) goto out_decode; switch (gss_cred->gc_service) { case RPC_GSS_SVC_NONE: break; case RPC_GSS_SVC_INTEGRITY: status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); if (status) 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) + (savedlen - head->iov_len); out_decode: status = decode(rqstp, p, obj); out: gss_put_ctx(ctx); dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, status); return status; } static const struct rpc_authops authgss_ops = { .owner = THIS_MODULE, .au_flavor = RPC_AUTH_GSS, #ifdef RPC_DEBUG .au_name = "RPCSEC_GSS", #endif .create = gss_create, .destroy = gss_destroy, .lookup_cred = gss_lookup_cred, .crcreate = gss_create_cred }; static const struct rpc_credops gss_credops = { .cr_name = "AUTH_GSS", .crdestroy = gss_destroy_cred, .cr_init = gss_cred_init, .crmatch = gss_match, .crmarshal = gss_marshal, .crrefresh = gss_refresh, .crvalidate = gss_validate, .crwrap_req = gss_wrap_req, .crunwrap_resp = gss_unwrap_resp, }; static struct rpc_pipe_ops gss_upcall_ops = { .upcall = gss_pipe_upcall, .downcall = gss_pipe_downcall, .destroy_msg = gss_pipe_destroy_msg, .release_pipe = gss_pipe_release, }; /* * Initialize RPCSEC_GSS module */ static int __init init_rpcsec_gss(void) { int err = 0; err = rpcauth_register(&authgss_ops); if (err) goto out; err = gss_svc_init(); if (err) goto out_unregister; return 0; out_unregister: rpcauth_unregister(&authgss_ops); out: return err; } static void __exit exit_rpcsec_gss(void) { gss_svc_shutdown(); rpcauth_unregister(&authgss_ops); } MODULE_LICENSE("GPL"); module_init(init_rpcsec_gss) module_exit(exit_rpcsec_gss)