| /* |
| * linux/fs/nfs/callback_xdr.c |
| * |
| * Copyright (C) 2004 Trond Myklebust |
| * |
| * NFSv4 callback encode/decode procedures |
| */ |
| #include <linux/kernel.h> |
| #include <linux/sunrpc/svc.h> |
| #include <linux/nfs4.h> |
| #include <linux/nfs_fs.h> |
| #include "nfs4_fs.h" |
| #include "callback.h" |
| |
| #define CB_OP_TAGLEN_MAXSZ (512) |
| #define CB_OP_HDR_RES_MAXSZ (2 + CB_OP_TAGLEN_MAXSZ) |
| #define CB_OP_GETATTR_BITMAP_MAXSZ (4) |
| #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \ |
| CB_OP_GETATTR_BITMAP_MAXSZ + \ |
| 2 + 2 + 3 + 3) |
| #define CB_OP_RECALL_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ) |
| |
| #define NFSDBG_FACILITY NFSDBG_CALLBACK |
| |
| typedef __be32 (*callback_process_op_t)(void *, void *); |
| typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *); |
| typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *); |
| |
| |
| struct callback_op { |
| callback_process_op_t process_op; |
| callback_decode_arg_t decode_args; |
| callback_encode_res_t encode_res; |
| long res_maxsize; |
| }; |
| |
| static struct callback_op callback_ops[]; |
| |
| static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp) |
| { |
| return htonl(NFS4_OK); |
| } |
| |
| static int nfs4_decode_void(struct svc_rqst *rqstp, uint32_t *p, void *dummy) |
| { |
| return xdr_argsize_check(rqstp, p); |
| } |
| |
| static int nfs4_encode_void(struct svc_rqst *rqstp, uint32_t *p, void *dummy) |
| { |
| return xdr_ressize_check(rqstp, p); |
| } |
| |
| static uint32_t *read_buf(struct xdr_stream *xdr, int nbytes) |
| { |
| uint32_t *p; |
| |
| p = xdr_inline_decode(xdr, nbytes); |
| if (unlikely(p == NULL)) |
| printk(KERN_WARNING "NFSv4 callback reply buffer overflowed!\n"); |
| return p; |
| } |
| |
| static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str) |
| { |
| uint32_t *p; |
| |
| p = read_buf(xdr, 4); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *len = ntohl(*p); |
| |
| if (*len != 0) { |
| p = read_buf(xdr, *len); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *str = (const char *)p; |
| } else |
| *str = NULL; |
| |
| return 0; |
| } |
| |
| static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh) |
| { |
| uint32_t *p; |
| |
| p = read_buf(xdr, 4); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| fh->size = ntohl(*p); |
| if (fh->size > NFS4_FHSIZE) |
| return htonl(NFS4ERR_BADHANDLE); |
| p = read_buf(xdr, fh->size); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| memcpy(&fh->data[0], p, fh->size); |
| memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size); |
| return 0; |
| } |
| |
| static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap) |
| { |
| uint32_t *p; |
| unsigned int attrlen; |
| |
| p = read_buf(xdr, 4); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| attrlen = ntohl(*p); |
| p = read_buf(xdr, attrlen << 2); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| if (likely(attrlen > 0)) |
| bitmap[0] = ntohl(*p++); |
| if (attrlen > 1) |
| bitmap[1] = ntohl(*p); |
| return 0; |
| } |
| |
| static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid) |
| { |
| uint32_t *p; |
| |
| p = read_buf(xdr, 16); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| memcpy(stateid->data, p, 16); |
| return 0; |
| } |
| |
| static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr) |
| { |
| uint32_t *p; |
| unsigned int minor_version; |
| __be32 status; |
| |
| status = decode_string(xdr, &hdr->taglen, &hdr->tag); |
| if (unlikely(status != 0)) |
| return status; |
| /* We do not like overly long tags! */ |
| if (hdr->taglen > CB_OP_TAGLEN_MAXSZ-12 || hdr->taglen < 0) { |
| printk("NFSv4 CALLBACK %s: client sent tag of length %u\n", |
| __FUNCTION__, hdr->taglen); |
| return htonl(NFS4ERR_RESOURCE); |
| } |
| p = read_buf(xdr, 12); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| minor_version = ntohl(*p++); |
| /* Check minor version is zero. */ |
| if (minor_version != 0) { |
| printk(KERN_WARNING "%s: NFSv4 server callback with illegal minor version %u!\n", |
| __FUNCTION__, minor_version); |
| return htonl(NFS4ERR_MINOR_VERS_MISMATCH); |
| } |
| hdr->callback_ident = ntohl(*p++); |
| hdr->nops = ntohl(*p); |
| return 0; |
| } |
| |
| static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op) |
| { |
| uint32_t *p; |
| p = read_buf(xdr, 4); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *op = ntohl(*p); |
| return 0; |
| } |
| |
| static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args) |
| { |
| __be32 status; |
| |
| status = decode_fh(xdr, &args->fh); |
| if (unlikely(status != 0)) |
| goto out; |
| args->addr = &rqstp->rq_addr; |
| status = decode_bitmap(xdr, args->bitmap); |
| out: |
| dprintk("%s: exit with status = %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args) |
| { |
| uint32_t *p; |
| __be32 status; |
| |
| args->addr = &rqstp->rq_addr; |
| status = decode_stateid(xdr, &args->stateid); |
| if (unlikely(status != 0)) |
| goto out; |
| p = read_buf(xdr, 4); |
| if (unlikely(p == NULL)) { |
| status = htonl(NFS4ERR_RESOURCE); |
| goto out; |
| } |
| args->truncate = ntohl(*p); |
| status = decode_fh(xdr, &args->fh); |
| out: |
| dprintk("%s: exit with status = %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str) |
| { |
| uint32_t *p; |
| |
| p = xdr_reserve_space(xdr, 4 + len); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| xdr_encode_opaque(p, str, len); |
| return 0; |
| } |
| |
| #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) |
| #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) |
| static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, uint32_t **savep) |
| { |
| uint32_t bm[2]; |
| uint32_t *p; |
| |
| bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0); |
| bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1); |
| if (bm[1] != 0) { |
| p = xdr_reserve_space(xdr, 16); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *p++ = htonl(2); |
| *p++ = bm[0]; |
| *p++ = bm[1]; |
| } else if (bm[0] != 0) { |
| p = xdr_reserve_space(xdr, 12); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *p++ = htonl(1); |
| *p++ = bm[0]; |
| } else { |
| p = xdr_reserve_space(xdr, 8); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *p++ = htonl(0); |
| } |
| *savep = p; |
| return 0; |
| } |
| |
| static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change) |
| { |
| uint32_t *p; |
| |
| if (!(bitmap[0] & FATTR4_WORD0_CHANGE)) |
| return 0; |
| p = xdr_reserve_space(xdr, 8); |
| if (unlikely(p == 0)) |
| return htonl(NFS4ERR_RESOURCE); |
| p = xdr_encode_hyper(p, change); |
| return 0; |
| } |
| |
| static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size) |
| { |
| uint32_t *p; |
| |
| if (!(bitmap[0] & FATTR4_WORD0_SIZE)) |
| return 0; |
| p = xdr_reserve_space(xdr, 8); |
| if (unlikely(p == 0)) |
| return htonl(NFS4ERR_RESOURCE); |
| p = xdr_encode_hyper(p, size); |
| return 0; |
| } |
| |
| static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time) |
| { |
| uint32_t *p; |
| |
| p = xdr_reserve_space(xdr, 12); |
| if (unlikely(p == 0)) |
| return htonl(NFS4ERR_RESOURCE); |
| p = xdr_encode_hyper(p, time->tv_sec); |
| *p = htonl(time->tv_nsec); |
| return 0; |
| } |
| |
| static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time) |
| { |
| if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA)) |
| return 0; |
| return encode_attr_time(xdr,time); |
| } |
| |
| static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time) |
| { |
| if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY)) |
| return 0; |
| return encode_attr_time(xdr,time); |
| } |
| |
| static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr) |
| { |
| __be32 status; |
| |
| hdr->status = xdr_reserve_space(xdr, 4); |
| if (unlikely(hdr->status == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| status = encode_string(xdr, hdr->taglen, hdr->tag); |
| if (unlikely(status != 0)) |
| return status; |
| hdr->nops = xdr_reserve_space(xdr, 4); |
| if (unlikely(hdr->nops == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| return 0; |
| } |
| |
| static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res) |
| { |
| uint32_t *p; |
| |
| p = xdr_reserve_space(xdr, 8); |
| if (unlikely(p == NULL)) |
| return htonl(NFS4ERR_RESOURCE); |
| *p++ = htonl(op); |
| *p = res; |
| return 0; |
| } |
| |
| static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res) |
| { |
| uint32_t *savep = NULL; |
| __be32 status = res->status; |
| |
| if (unlikely(status != 0)) |
| goto out; |
| status = encode_attr_bitmap(xdr, res->bitmap, &savep); |
| if (unlikely(status != 0)) |
| goto out; |
| status = encode_attr_change(xdr, res->bitmap, res->change_attr); |
| if (unlikely(status != 0)) |
| goto out; |
| status = encode_attr_size(xdr, res->bitmap, res->size); |
| if (unlikely(status != 0)) |
| goto out; |
| status = encode_attr_ctime(xdr, res->bitmap, &res->ctime); |
| if (unlikely(status != 0)) |
| goto out; |
| status = encode_attr_mtime(xdr, res->bitmap, &res->mtime); |
| *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1))); |
| out: |
| dprintk("%s: exit with status = %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| static __be32 process_op(struct svc_rqst *rqstp, |
| struct xdr_stream *xdr_in, void *argp, |
| struct xdr_stream *xdr_out, void *resp) |
| { |
| struct callback_op *op = &callback_ops[0]; |
| unsigned int op_nr = OP_CB_ILLEGAL; |
| __be32 status = 0; |
| long maxlen; |
| __be32 res; |
| |
| dprintk("%s: start\n", __FUNCTION__); |
| status = decode_op_hdr(xdr_in, &op_nr); |
| if (likely(status == 0)) { |
| switch (op_nr) { |
| case OP_CB_GETATTR: |
| case OP_CB_RECALL: |
| op = &callback_ops[op_nr]; |
| break; |
| default: |
| op_nr = OP_CB_ILLEGAL; |
| op = &callback_ops[0]; |
| status = htonl(NFS4ERR_OP_ILLEGAL); |
| } |
| } |
| |
| maxlen = xdr_out->end - xdr_out->p; |
| if (maxlen > 0 && maxlen < PAGE_SIZE) { |
| if (likely(status == 0 && op->decode_args != NULL)) |
| status = op->decode_args(rqstp, xdr_in, argp); |
| if (likely(status == 0 && op->process_op != NULL)) |
| status = op->process_op(argp, resp); |
| } else |
| status = htonl(NFS4ERR_RESOURCE); |
| |
| res = encode_op_hdr(xdr_out, op_nr, status); |
| if (status == 0) |
| status = res; |
| if (op->encode_res != NULL && status == 0) |
| status = op->encode_res(rqstp, xdr_out, resp); |
| dprintk("%s: done, status = %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| /* |
| * Decode, process and encode a COMPOUND |
| */ |
| static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp) |
| { |
| struct cb_compound_hdr_arg hdr_arg; |
| struct cb_compound_hdr_res hdr_res; |
| struct xdr_stream xdr_in, xdr_out; |
| uint32_t *p; |
| __be32 status; |
| unsigned int nops = 1; |
| |
| dprintk("%s: start\n", __FUNCTION__); |
| |
| xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base); |
| |
| p = (uint32_t*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len); |
| xdr_init_encode(&xdr_out, &rqstp->rq_res, p); |
| |
| decode_compound_hdr_arg(&xdr_in, &hdr_arg); |
| hdr_res.taglen = hdr_arg.taglen; |
| hdr_res.tag = hdr_arg.tag; |
| hdr_res.nops = NULL; |
| encode_compound_hdr_res(&xdr_out, &hdr_res); |
| |
| for (;;) { |
| status = process_op(rqstp, &xdr_in, argp, &xdr_out, resp); |
| if (status != 0) |
| break; |
| if (nops == hdr_arg.nops) |
| break; |
| nops++; |
| } |
| *hdr_res.status = status; |
| *hdr_res.nops = htonl(nops); |
| dprintk("%s: done, status = %u\n", __FUNCTION__, status); |
| return rpc_success; |
| } |
| |
| /* |
| * Define NFS4 callback COMPOUND ops. |
| */ |
| static struct callback_op callback_ops[] = { |
| [0] = { |
| .res_maxsize = CB_OP_HDR_RES_MAXSZ, |
| }, |
| [OP_CB_GETATTR] = { |
| .process_op = (callback_process_op_t)nfs4_callback_getattr, |
| .decode_args = (callback_decode_arg_t)decode_getattr_args, |
| .encode_res = (callback_encode_res_t)encode_getattr_res, |
| .res_maxsize = CB_OP_GETATTR_RES_MAXSZ, |
| }, |
| [OP_CB_RECALL] = { |
| .process_op = (callback_process_op_t)nfs4_callback_recall, |
| .decode_args = (callback_decode_arg_t)decode_recall_args, |
| .res_maxsize = CB_OP_RECALL_RES_MAXSZ, |
| } |
| }; |
| |
| /* |
| * Define NFS4 callback procedures |
| */ |
| static struct svc_procedure nfs4_callback_procedures1[] = { |
| [CB_NULL] = { |
| .pc_func = nfs4_callback_null, |
| .pc_decode = (kxdrproc_t)nfs4_decode_void, |
| .pc_encode = (kxdrproc_t)nfs4_encode_void, |
| .pc_xdrressize = 1, |
| }, |
| [CB_COMPOUND] = { |
| .pc_func = nfs4_callback_compound, |
| .pc_encode = (kxdrproc_t)nfs4_encode_void, |
| .pc_argsize = 256, |
| .pc_ressize = 256, |
| .pc_xdrressize = NFS4_CALLBACK_BUFSIZE, |
| } |
| }; |
| |
| struct svc_version nfs4_callback_version1 = { |
| .vs_vers = 1, |
| .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1), |
| .vs_proc = nfs4_callback_procedures1, |
| .vs_xdrsize = NFS4_CALLBACK_XDRSIZE, |
| .vs_dispatch = NULL, |
| }; |
| |