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diff --git a/src/backends/shss/shss.c b/src/backends/shss/shss.c
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+++ b/src/backends/shss/shss.c
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+/*
+ * Copyright(c) 2015 NTT corp. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * 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.  THIS SOFTWARE IS PROVIDED BY
+ * THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER 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.
+ *
+ * liberasurecode shss backend
+ *
+ * Please contact us if you are insterested in the NTT backend (welcome!):
+ * Kota Tsuyuzaki <tsuyuzaki.kota@lab.ntt.co.jp>
+ *
+ * vi: set noai tw=79 ts=4 sw=4:
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <alloca.h>
+
+#include "erasurecode.h"
+#include "erasurecode_helpers.h"
+#include "erasurecode_backend.h"
+
+/* Forward declarations */
+struct ec_backend shss;
+struct ec_backend_op_stubs shss_ops;
+
+typedef int (*shss_encode_func)(char **, size_t, int, int, int, int, long long *);
+typedef int (*shss_decode_func)(char **, size_t, int *, int, int, int, int, int, long long *);
+typedef int (*shss_reconstruct_func)(char **, size_t, int *, int, int *, int, int, int, int, int, long long *);
+
+struct shss_descriptor {
+    /* calls required for init */
+    shss_encode_func ssencode;
+    shss_decode_func ssdecode;
+    shss_reconstruct_func ssreconst;
+
+    /* fields needed to hold state */
+    int k;
+    int m;
+    int n;
+    int w;
+    int aes_bit_length;
+};
+
+#define SHSS_LIB_VER_STR "1.0"
+#define SHSS_LIB_NAME "shss"
+#if defined(__MACOS__) || defined(__MACOSX__) || defined(__OSX__) || defined(__APPLE__)
+#define SHSS_SO_NAME "libshss.dylib"
+#else
+#define SHSS_SO_NAME "libshss.so"
+#endif
+#define DEFAULT_W 128
+
+/* TODO:
+   metadata_adder is still in discussion. shss needs to a fixed value to allocate extra bytes
+   for *each* fragment. However, current liberasurecode calculates the extra bytes as
+   "(alined_data_size + metadata_adder) / k" so that shss has to define the METADATA as a big value
+   to alloc enough memory for the maximum number of k even if k is smaller than the maximum value.
+
+   i.e. (shss specification is)
+   Enough Extra Bytes (for *each* fragment): 32
+   The Maximum Number: 20 (k=20)
+*/
+#define METADATA 32 * 20
+
+static int shss_encode(void *desc, char **data, char **parity,
+        int blocksize)
+{
+    int i;
+    int ret = 0;
+    int priv_bitnum = 128; // privacy bit number 0 or 128(default) or 256
+    int chksum = 0; // chksum 0 or 64
+    char **encoded;
+    long long einfo;
+    struct shss_descriptor *xdesc =
+        (struct shss_descriptor *) desc;
+
+    if (xdesc->aes_bit_length != -1) {
+        priv_bitnum = xdesc->aes_bit_length;
+    }
+
+    encoded = alloca(sizeof(char*)*xdesc->n);
+
+    for (i = 0; i<xdesc->k; i++) encoded[i] = (char*)data[i];
+    for (i = 0; i<xdesc->m; i++) encoded[i+xdesc->k] = (char*)parity[i];
+
+    ret = xdesc->ssencode((char**)encoded, (size_t)blocksize,
+                        xdesc->k, xdesc->m, priv_bitnum, chksum, &einfo);
+
+    if (ret > 0) {
+        return -ret;
+    }
+
+    return 0;
+}
+
+static int shss_decode(void *desc, char **data, char **parity,
+        int *missing_idxs, int blocksize)
+{
+    int i;
+    int missing_size = 0;
+    int ret = 0;
+    int priv_bitnum = 128; // privacy bit number 0 or 128(default) or 256
+    int chksum = 0; // chksum 0 or 64
+    char **decoded;
+    long long einfo;
+    struct shss_descriptor *xdesc =
+        (struct shss_descriptor *) desc;
+
+    if (xdesc->aes_bit_length != -1) {
+        priv_bitnum = xdesc->aes_bit_length;
+    }
+
+    decoded = alloca(sizeof(char*)*xdesc->n);
+
+    for (i = 0; i<xdesc->k; i++) decoded[i] = (char*)data[i];
+    for (i = 0; i<xdesc->m; i++) decoded[i+xdesc->k] = (char*)parity[i];
+    for (i = 0; i<xdesc->n; i++) {
+        if (i == missing_idxs[missing_size]) {
+            missing_size++;
+        }
+    }
+
+    ret = xdesc->ssdecode((char**)decoded, (size_t)blocksize, missing_idxs, missing_size,
+                         xdesc->k, xdesc->m, priv_bitnum, chksum, &einfo);
+
+    if (ret > 0) {
+        return -ret;
+    }
+
+    return 0;
+}
+
+static int shss_reconstruct(void *desc, char **data, char **parity,
+        int *missing_idxs, int destination_idx, int blocksize)
+{
+    int i;
+    int missing_size = 0;
+    int ret = 0;
+    int priv_bitnum = 128; // privacy bit number 0 or 128(default) or 256
+    int chksum = 0; // chksum 0 or 64
+    int dst_size = 1;
+    char **reconstructed;
+    long long einfo;
+    struct shss_descriptor *xdesc =
+        (struct shss_descriptor *) desc;
+
+    if (xdesc->aes_bit_length != -1) {
+        priv_bitnum = xdesc->aes_bit_length;
+    }
+
+    reconstructed = alloca(sizeof(char*)*xdesc->n);
+
+    for (i = 0; i<xdesc->k; i++) reconstructed[i] = (char*)data[i];
+    for (i = 0; i<xdesc->m; i++) reconstructed[i+xdesc->k] = (char*)parity[i];
+    for (i = 0; i<xdesc->n; i++) {
+        if (i == missing_idxs[missing_size]) {
+            missing_size++;
+        }
+    }
+
+    ret = xdesc->ssreconst((char**)reconstructed, (size_t)blocksize,
+                          &destination_idx, dst_size, missing_idxs, missing_size, xdesc->k,
+                          xdesc->m, priv_bitnum, chksum, &einfo);
+
+    if (ret > 0) {
+        return -ret;
+    }
+
+    return 0;
+}
+
+static int shss_fragments_needed(void *desc, int *missing_idxs,
+        int *fragments_to_exclude, int *fragments_needed)
+{
+    struct shss_descriptor *xdesc =
+        (struct shss_descriptor *) desc;
+    uint64_t exclude_bm = convert_list_to_bitmap(fragments_to_exclude);
+    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs) | exclude_bm;
+    int i;
+    int j = 0;
+    int ret = -101;
+
+    for (i = 0; i < xdesc->n; i++) {
+        if (!(missing_bm & (1 << i))) {
+            fragments_needed[j] = i;
+            j++;
+        }
+        if (j == xdesc->k) {
+            ret = 0;
+            fragments_needed[j] = -1;
+            break;
+        }
+    }
+
+    return ret;
+}
+
+/**
+ * Return the element-size, which is the number of bits stored
+ * on a given device, per codeword.  This is usually just 'w'.
+ */
+static int shss_element_size(void* desc)
+{
+    return DEFAULT_W;
+}
+
+static void * shss_init(struct ec_backend_args *args, void *backend_sohandle)
+{
+    static struct shss_descriptor xdesc;
+
+    xdesc.k = args->uargs.k;
+    xdesc.m = args->uargs.m;
+    xdesc.n = args->uargs.k + args->uargs.m;
+    xdesc.w = DEFAULT_W;
+    args->uargs.w = DEFAULT_W;
+
+    /* Sample on how to pass extra args to the backend */
+    // TODO: Need discussion how to pass extra args.
+    int *priv = (int *)args->uargs.priv_args2;
+    xdesc.aes_bit_length = priv[0]; // AES bit number
+
+    union {
+        shss_encode_func encodep;
+        shss_decode_func decodep;
+        shss_reconstruct_func reconp;
+        void *vptr;
+    } func_handle;
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "ssencode");
+    xdesc.ssencode = func_handle.encodep;
+    if (NULL == xdesc.ssencode) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "ssdecode");
+    xdesc.ssdecode = func_handle.decodep;
+    if (NULL == xdesc.ssdecode) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "ssreconst");
+    xdesc.ssreconst = func_handle.reconp;
+    if (NULL == xdesc.ssreconst) {
+        goto error;
+    }
+
+    return (void *)&xdesc;
+
+error:
+    return NULL;
+}
+
+static int shss_exit(void *desc)
+{
+    return 0;
+}
+
+struct ec_backend_op_stubs shss_op_stubs = {
+    .INIT                       = shss_init,
+    .EXIT                       = shss_exit,
+    .ENCODE                     = shss_encode,
+    .DECODE                     = shss_decode,
+    .FRAGSNEEDED                = shss_fragments_needed,
+    .RECONSTRUCT                = shss_reconstruct,
+    .ELEMENTSIZE                = shss_element_size,
+};
+
+struct ec_backend_common backend_shss = {
+    .id                         = EC_BACKEND_SHSS,
+    .name                       = SHSS_LIB_NAME,
+    .soname                     = SHSS_SO_NAME,
+    .soversion                  = SHSS_LIB_VER_STR,
+    .ops                        = &shss_op_stubs,
+    .metadata_adder             = METADATA,
+};