From 0e779aa70308462e45f7cd1a54de418dfe101694 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 20 Mar 2018 17:03:05 -0400 Subject: SUNRPC: Add helpers for decoding opaque and string types Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker --- include/linux/sunrpc/xdr.h | 6 ++++ net/sunrpc/xdr.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 88 insertions(+) diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h index d950223c64b1..7e609de34d85 100644 --- a/include/linux/sunrpc/xdr.h +++ b/include/linux/sunrpc/xdr.h @@ -253,6 +253,12 @@ xdr_stream_remaining(const struct xdr_stream *xdr) return xdr->nwords << 2; } +ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, + size_t size); +ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, + size_t maxlen, gfp_t gfp_flags); +ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, + size_t size); ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, size_t maxlen, gfp_t gfp_flags); /** diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index e34f4ee7f2b6..30afbd236656 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -1518,6 +1518,88 @@ out: } EXPORT_SYMBOL_GPL(xdr_process_buf); +/** + * xdr_stream_decode_opaque - Decode variable length opaque + * @xdr: pointer to xdr_stream + * @ptr: location to store opaque data + * @size: size of storage buffer @ptr + * + * Return values: + * On success, returns size of object stored in *@ptr + * %-EBADMSG on XDR buffer overflow + * %-EMSGSIZE on overflow of storage buffer @ptr + */ +ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, size_t size) +{ + ssize_t ret; + void *p; + + ret = xdr_stream_decode_opaque_inline(xdr, &p, size); + if (ret <= 0) + return ret; + memcpy(ptr, p, ret); + return ret; +} +EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque); + +/** + * xdr_stream_decode_opaque_dup - Decode and duplicate variable length opaque + * @xdr: pointer to xdr_stream + * @ptr: location to store pointer to opaque data + * @maxlen: maximum acceptable object size + * @gfp_flags: GFP mask to use + * + * Return values: + * On success, returns size of object stored in *@ptr + * %-EBADMSG on XDR buffer overflow + * %-EMSGSIZE if the size of the object would exceed @maxlen + * %-ENOMEM on memory allocation failure + */ +ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, + size_t maxlen, gfp_t gfp_flags) +{ + ssize_t ret; + void *p; + + ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen); + if (ret > 0) { + *ptr = kmemdup(p, ret, gfp_flags); + if (*ptr != NULL) + return ret; + ret = -ENOMEM; + } + *ptr = NULL; + return ret; +} +EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque_dup); + +/** + * xdr_stream_decode_string - Decode variable length string + * @xdr: pointer to xdr_stream + * @str: location to store string + * @size: size of storage buffer @str + * + * Return values: + * On success, returns length of NUL-terminated string stored in *@str + * %-EBADMSG on XDR buffer overflow + * %-EMSGSIZE on overflow of storage buffer @str + */ +ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, size_t size) +{ + ssize_t ret; + void *p; + + ret = xdr_stream_decode_opaque_inline(xdr, &p, size); + if (ret > 0) { + memcpy(str, p, ret); + str[ret] = '\0'; + return strlen(str); + } + *str = '\0'; + return ret; +} +EXPORT_SYMBOL_GPL(xdr_stream_decode_string); + /** * xdr_stream_decode_string_dup - Decode and duplicate variable length string * @xdr: pointer to xdr_stream -- cgit v1.2.3