diff options
| -rw-r--r-- | net/sunrpc/auth_gss/auth_gss.c | 116 |
1 files changed, 96 insertions, 20 deletions
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index fe06acd6029b..153b3e11e61a 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -72,7 +72,13 @@ struct gss_auth { struct gss_api_mech *mech; enum rpc_gss_svc service; struct rpc_clnt *client; - struct dentry *dentry; + /* + * There are two upcall pipes; dentry[1], named "gssd", is used + * for the new text-based upcall; dentry[0] is named after the + * mechanism (for example, "krb5") and exists for + * backwards-compatibility with older gssd's. + */ + struct dentry *dentry[2]; }; /* pipe_version >= 0 if and only if someone has a pipe open. */ @@ -83,7 +89,8 @@ static struct rpc_wait_queue pipe_version_rpc_waitqueue; static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue); static void gss_free_ctx(struct gss_cl_ctx *); -static struct rpc_pipe_ops gss_upcall_ops; +static struct rpc_pipe_ops gss_upcall_ops_v0; +static struct rpc_pipe_ops gss_upcall_ops_v1; static inline struct gss_cl_ctx * gss_get_ctx(struct gss_cl_ctx *ctx) @@ -227,6 +234,7 @@ err: return p; } +#define UPCALL_BUF_LEN 128 struct gss_upcall_msg { atomic_t count; @@ -238,6 +246,7 @@ struct gss_upcall_msg { struct rpc_wait_queue rpc_waitqueue; wait_queue_head_t waitqueue; struct gss_cl_ctx *ctx; + char databuf[UPCALL_BUF_LEN]; }; static int get_pipe_version(void) @@ -247,7 +256,7 @@ static int get_pipe_version(void) spin_lock(&pipe_version_lock); if (pipe_version >= 0) { atomic_inc(&pipe_users); - ret = 0; + ret = pipe_version; } else ret = -EAGAIN; spin_unlock(&pipe_version_lock); @@ -353,6 +362,29 @@ gss_upcall_callback(struct rpc_task *task) gss_release_msg(gss_msg); } +static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) +{ + gss_msg->msg.data = &gss_msg->uid; + gss_msg->msg.len = sizeof(gss_msg->uid); +} + +static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg) +{ + gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d\n", + gss_msg->auth->mech->gm_name, + gss_msg->uid); + gss_msg->msg.data = gss_msg->databuf; + BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); +} + +static void gss_encode_msg(struct gss_upcall_msg *gss_msg) +{ + if (pipe_version == 0) + gss_encode_v0_msg(gss_msg); + else /* pipe_version == 1 */ + gss_encode_v1_msg(gss_msg); +} + static inline struct gss_upcall_msg * gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid) { @@ -367,15 +399,14 @@ gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid) kfree(gss_msg); return ERR_PTR(vers); } - gss_msg->inode = RPC_I(gss_auth->dentry->d_inode); + gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode); 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; + gss_encode_msg(gss_msg); return gss_msg; } @@ -613,18 +644,36 @@ out: return err; } -static int -gss_pipe_open(struct inode *inode) +static int gss_pipe_open(struct inode *inode, int new_version) { + int ret = 0; + spin_lock(&pipe_version_lock); if (pipe_version < 0) { - pipe_version = 0; + /* First open of any gss pipe determines the version: */ + pipe_version = new_version; rpc_wake_up(&pipe_version_rpc_waitqueue); wake_up(&pipe_version_waitqueue); + } else if (pipe_version != new_version) { + /* Trying to open a pipe of a different version */ + ret = -EBUSY; + goto out; } atomic_inc(&pipe_users); +out: spin_unlock(&pipe_version_lock); - return 0; + return ret; + +} + +static int gss_pipe_open_v0(struct inode *inode) +{ + return gss_pipe_open(inode, 0); +} + +static int gss_pipe_open_v1(struct inode *inode) +{ + return gss_pipe_open(inode, 1); } static void @@ -702,20 +751,38 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) atomic_set(&auth->au_count, 1); kref_init(&gss_auth->kref); - 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); + /* + * Note: if we created the old pipe first, then someone who + * examined the directory at the right moment might conclude + * that we supported only the old pipe. So we instead create + * the new pipe first. + */ + gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_dentry, + "gssd", + clnt, &gss_upcall_ops_v1, + RPC_PIPE_WAIT_FOR_OPEN); + if (IS_ERR(gss_auth->dentry[1])) { + err = PTR_ERR(gss_auth->dentry[1]); goto err_put_mech; } + gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_dentry, + gss_auth->mech->gm_name, + clnt, &gss_upcall_ops_v0, + RPC_PIPE_WAIT_FOR_OPEN); + if (IS_ERR(gss_auth->dentry[0])) { + err = PTR_ERR(gss_auth->dentry[0]); + goto err_unlink_pipe_1; + } err = rpcauth_init_credcache(auth); if (err) - goto err_unlink_pipe; + goto err_unlink_pipe_0; return auth; -err_unlink_pipe: - rpc_unlink(gss_auth->dentry); +err_unlink_pipe_0: + rpc_unlink(gss_auth->dentry[0]); +err_unlink_pipe_1: + rpc_unlink(gss_auth->dentry[1]); err_put_mech: gss_mech_put(gss_auth->mech); err_free: @@ -728,7 +795,8 @@ out_dec: static void gss_free(struct gss_auth *gss_auth) { - rpc_unlink(gss_auth->dentry); + rpc_unlink(gss_auth->dentry[1]); + rpc_unlink(gss_auth->dentry[0]); gss_mech_put(gss_auth->mech); kfree(gss_auth); @@ -1419,11 +1487,19 @@ static const struct rpc_credops gss_nullops = { .crunwrap_resp = gss_unwrap_resp, }; -static struct rpc_pipe_ops gss_upcall_ops = { +static struct rpc_pipe_ops gss_upcall_ops_v0 = { + .upcall = gss_pipe_upcall, + .downcall = gss_pipe_downcall, + .destroy_msg = gss_pipe_destroy_msg, + .open_pipe = gss_pipe_open_v0, + .release_pipe = gss_pipe_release, +}; + +static struct rpc_pipe_ops gss_upcall_ops_v1 = { .upcall = gss_pipe_upcall, .downcall = gss_pipe_downcall, .destroy_msg = gss_pipe_destroy_msg, - .open_pipe = gss_pipe_open, + .open_pipe = gss_pipe_open_v1, .release_pipe = gss_pipe_release, }; |