// SPDX-License-Identifier: GPL-2.0
/*
 * Process version 2 NFSACL requests.
 *
 * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
 */

#include "nfsd.h"
/* FIXME: nfsacl.h is a broken header */
#include <linux/nfsacl.h>
#include <linux/gfp.h>
#include "cache.h"
#include "xdr3.h"
#include "vfs.h"

#define NFSDDBG_FACILITY                NFSDDBG_PROC

/*
 * NULL call.
 */
static __be32
nfsacld_proc_null(struct svc_rqst *rqstp)
{
        return rpc_success;
}

/*
 * Get the Access and/or Default ACL of a file.
 */
static __be32 nfsacld_proc_getacl(struct svc_rqst *rqstp)
{
        struct nfsd3_getaclargs *argp = rqstp->rq_argp;
        struct nfsd3_getaclres *resp = rqstp->rq_resp;
        struct posix_acl *acl;
        struct inode *inode;
        svc_fh *fh;

        dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));

        fh = fh_copy(&resp->fh, &argp->fh);
        resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
        if (resp->status != nfs_ok)
                goto out;

        inode = d_inode(fh->fh_dentry);

        if (argp->mask & ~NFS_ACL_MASK) {
                resp->status = nfserr_io;
                goto out;
        }
        resp->mask = argp->mask;

        resp->status = fh_getattr(fh, &resp->stat);
        if (resp->status != nfs_ok)
                goto out;

        if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
                acl = get_inode_acl(inode, ACL_TYPE_ACCESS);
                if (acl == NULL) {
                        /* Solaris returns the inode's minimum ACL. */
                        acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
                }
                if (IS_ERR(acl)) {
                        resp->status = nfserrno(PTR_ERR(acl));
                        goto fail;
                }
                resp->acl_access = acl;
        }
        if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
                /* Check how Solaris handles requests for the Default ACL
                   of a non-directory! */
                acl = get_inode_acl(inode, ACL_TYPE_DEFAULT);
                if (IS_ERR(acl)) {
                        resp->status = nfserrno(PTR_ERR(acl));
                        goto fail;
                }
                resp->acl_default = acl;
        }

        /* resp->acl_{access,default} are released in nfssvc_release_getacl. */
out:
        return rpc_success;

fail:
        posix_acl_release(resp->acl_access);
        posix_acl_release(resp->acl_default);
        resp->acl_access = NULL;
        resp->acl_default = NULL;
        goto out;
}

/*
 * Set the Access and/or Default ACL of a file.
 */
static __be32 nfsacld_proc_setacl(struct svc_rqst *rqstp)
{
        struct nfsd3_setaclargs *argp = rqstp->rq_argp;
        struct nfsd_attrstat *resp = rqstp->rq_resp;
        struct inode *inode;
        svc_fh *fh;
        int error;

        dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));

        fh = fh_copy(&resp->fh, &argp->fh);
        resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
        if (resp->status != nfs_ok)
                goto out;

        inode = d_inode(fh->fh_dentry);

        error = fh_want_write(fh);
        if (error)
                goto out_errno;

        inode_lock(inode);

        error = set_posix_acl(&nop_mnt_idmap, fh->fh_dentry, ACL_TYPE_ACCESS,
                              argp->acl_access);
        if (error)
                goto out_drop_lock;
        error = set_posix_acl(&nop_mnt_idmap, fh->fh_dentry, ACL_TYPE_DEFAULT,
                              argp->acl_default);
        if (error)
                goto out_drop_lock;

        inode_unlock(inode);

        fh_drop_write(fh);

        resp->status = fh_getattr(fh, &resp->stat);

out:
        /* argp->acl_{access,default} may have been allocated in
           nfssvc_decode_setaclargs. */
        posix_acl_release(argp->acl_access);
        posix_acl_release(argp->acl_default);
        return rpc_success;

out_drop_lock:
        inode_unlock(inode);
        fh_drop_write(fh);
out_errno:
        resp->status = nfserrno(error);
        goto out;
}

/*
 * Check file attributes
 */
static __be32 nfsacld_proc_getattr(struct svc_rqst *rqstp)
{
        struct nfsd_fhandle *argp = rqstp->rq_argp;
        struct nfsd_attrstat *resp = rqstp->rq_resp;

        dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));

        fh_copy(&resp->fh, &argp->fh);
        resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
        if (resp->status != nfs_ok)
                goto out;
        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/*
 * Check file access
 */
static __be32 nfsacld_proc_access(struct svc_rqst *rqstp)
{
        struct nfsd3_accessargs *argp = rqstp->rq_argp;
        struct nfsd3_accessres *resp = rqstp->rq_resp;

        dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
                        SVCFH_fmt(&argp->fh),
                        argp->access);

        fh_copy(&resp->fh, &argp->fh);
        resp->access = argp->access;
        resp->status = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
        if (resp->status != nfs_ok)
                goto out;
        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/*
 * XDR decode functions
 */

static bool
nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
        struct nfsd3_getaclargs *argp = rqstp->rq_argp;

        if (!svcxdr_decode_fhandle(xdr, &argp->fh))
                return false;
        if (xdr_stream_decode_u32(xdr, &argp->mask) < 0)
                return false;

        return true;
}

static bool
nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
        struct nfsd3_setaclargs *argp = rqstp->rq_argp;

        if (!svcxdr_decode_fhandle(xdr, &argp->fh))
                return false;
        if (xdr_stream_decode_u32(xdr, &argp->mask) < 0)
                return false;
        if (argp->mask & ~NFS_ACL_MASK)
                return false;
        if (!nfs_stream_decode_acl(xdr, NULL, (argp->mask & NFS_ACL) ?
                                   &argp->acl_access : NULL))
                return false;
        if (!nfs_stream_decode_acl(xdr, NULL, (argp->mask & NFS_DFACL) ?
                                   &argp->acl_default : NULL))
                return false;

        return true;
}

static bool
nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
        struct nfsd3_accessargs *args = rqstp->rq_argp;

        if (!svcxdr_decode_fhandle(xdr, &args->fh))
                return false;
        if (xdr_stream_decode_u32(xdr, &args->access) < 0)
                return false;

        return true;
}

/*
 * XDR encode functions
 */

/* GETACL */
static bool
nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
        struct nfsd3_getaclres *resp = rqstp->rq_resp;
        struct dentry *dentry = resp->fh.fh_dentry;
        struct inode *inode;

        if (!svcxdr_encode_stat(xdr, resp->status))
                return false;

        if (dentry == NULL || d_really_is_negative(dentry))
                return true;
        inode = d_inode(dentry);

        if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
                return false;
        if (xdr_stream_encode_u32(xdr, resp->mask) < 0)
                return false;

        if (!nfs_stream_encode_acl(xdr, inode, resp->acl_access,
                                   resp->mask & NFS_ACL, 0))
                return false;
        if (!nfs_stream_encode_acl(xdr, inode, resp->acl_default,
                                   resp->mask & NFS_DFACL, NFS_ACL_DEFAULT))
                return false;

        return true;
}

/* ACCESS */
static bool
nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
        struct nfsd3_accessres *resp = rqstp->rq_resp;

        if (!svcxdr_encode_stat(xdr, resp->status))
                return false;
        switch (resp->status) {
        case nfs_ok:
                if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
                        return false;
                if (xdr_stream_encode_u32(xdr, resp->access) < 0)
                        return false;
                break;
        }

        return true;
}

/*
 * XDR release functions
 */
static void nfsaclsvc_release_getacl(struct svc_rqst *rqstp)
{
        struct nfsd3_getaclres *resp = rqstp->rq_resp;

        fh_put(&resp->fh);
        posix_acl_release(resp->acl_access);
        posix_acl_release(resp->acl_default);
}

static void nfsaclsvc_release_access(struct svc_rqst *rqstp)
{
        struct nfsd3_accessres *resp = rqstp->rq_resp;

        fh_put(&resp->fh);
}

#define ST 1            /* status*/
#define AT 21           /* attributes */
#define pAT (1+AT)      /* post attributes - conditional */
#define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */

static const struct svc_procedure nfsd_acl_procedures2[5] = {
        [ACLPROC2_NULL] = {
                .pc_func = nfsacld_proc_null,
                .pc_decode = nfssvc_decode_voidarg,
                .pc_encode = nfssvc_encode_voidres,
                .pc_argsize = sizeof(struct nfsd_voidargs),
                .pc_argzero = sizeof(struct nfsd_voidargs),
                .pc_ressize = sizeof(struct nfsd_voidres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST,
                .pc_name = "NULL",
        },
        [ACLPROC2_GETACL] = {
                .pc_func = nfsacld_proc_getacl,
                .pc_decode = nfsaclsvc_decode_getaclargs,
                .pc_encode = nfsaclsvc_encode_getaclres,
                .pc_release = nfsaclsvc_release_getacl,
                .pc_argsize = sizeof(struct nfsd3_getaclargs),
                .pc_argzero = sizeof(struct nfsd3_getaclargs),
                .pc_ressize = sizeof(struct nfsd3_getaclres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+1+2*(1+ACL),
                .pc_name = "GETACL",
        },
        [ACLPROC2_SETACL] = {
                .pc_func = nfsacld_proc_setacl,
                .pc_decode = nfsaclsvc_decode_setaclargs,
                .pc_encode = nfssvc_encode_attrstatres,
                .pc_release = nfssvc_release_attrstat,
                .pc_argsize = sizeof(struct nfsd3_setaclargs),
                .pc_argzero = sizeof(struct nfsd3_setaclargs),
                .pc_ressize = sizeof(struct nfsd_attrstat),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+AT,
                .pc_name = "SETACL",
        },
        [ACLPROC2_GETATTR] = {
                .pc_func = nfsacld_proc_getattr,
                .pc_decode = nfssvc_decode_fhandleargs,
                .pc_encode = nfssvc_encode_attrstatres,
                .pc_release = nfssvc_release_attrstat,
                .pc_argsize = sizeof(struct nfsd_fhandle),
                .pc_argzero = sizeof(struct nfsd_fhandle),
                .pc_ressize = sizeof(struct nfsd_attrstat),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+AT,
                .pc_name = "GETATTR",
        },
        [ACLPROC2_ACCESS] = {
                .pc_func = nfsacld_proc_access,
                .pc_decode = nfsaclsvc_decode_accessargs,
                .pc_encode = nfsaclsvc_encode_accessres,
                .pc_release = nfsaclsvc_release_access,
                .pc_argsize = sizeof(struct nfsd3_accessargs),
                .pc_argzero = sizeof(struct nfsd3_accessargs),
                .pc_ressize = sizeof(struct nfsd3_accessres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+AT+1,
                .pc_name = "SETATTR",
        },
};

static DEFINE_PER_CPU_ALIGNED(unsigned long,
                              nfsd_acl_count2[ARRAY_SIZE(nfsd_acl_procedures2)]);
const struct svc_version nfsd_acl_version2 = {
        .vs_vers        = 2,
        .vs_nproc       = ARRAY_SIZE(nfsd_acl_procedures2),
        .vs_proc        = nfsd_acl_procedures2,
        .vs_count       = nfsd_acl_count2,
        .vs_dispatch    = nfsd_dispatch,
        .vs_xdrsize     = NFS3_SVC_XDRSIZE,
};