kdbus: generare bloom filters properly for messages we send

9 files changed, 615 insertions, 14 deletions

diff --git a/Makefile.am b/Makefile.am
index eee73e5950..5a632a9093 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -680,7 +680,9 @@ libsystemd_shared_la_SOURCES = \
 	src/shared/calendarspec.h \
 	src/shared/fileio.c \
 	src/shared/fileio.h \
-	src/shared/output-mode.h
+	src/shared/output-mode.h \
+	src/shared/MurmurHash3.c \
+	src/shared/MurmurHash3.h
 
 #-------------------------------------------------------------------------------
 noinst_LTLIBRARIES += \
@@ -1711,7 +1713,9 @@ libsystemd_bus_la_SOURCES = \
 	src/libsystemd-bus/bus-type.c \
 	src/libsystemd-bus/bus-type.h \
 	src/libsystemd-bus/bus-match.c \
-	src/libsystemd-bus/bus-match.h
+	src/libsystemd-bus/bus-match.h \
+	src/libsystemd-bus/bus-bloom.c \
+	src/libsystemd-bus/bus-bloom.h
 
 libsystemd_bus_la_LIBADD =  \
 	libsystemd-id128-internal.la \
diff --git a/src/libsystemd-bus/bus-bloom.c b/src/libsystemd-bus/bus-bloom.c
new file mode 100644
index 0000000000..cb65e47b4c
--- /dev/null
+++ b/src/libsystemd-bus/bus-bloom.c
@@ -0,0 +1,93 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "util.h"
+#include "MurmurHash3.h"
+
+#include "bus-bloom.h"
+
+static inline void set_bit(uint64_t filter[], unsigned b) {
+        filter[b >> 6] |= 1ULL << (b & 63);
+}
+
+void bloom_add_data(uint64_t filter[BLOOM_SIZE/8], const void *data, size_t n) {
+        uint16_t hash[8];
+        unsigned k = 0;
+
+        /*
+         * Our bloom filter has the following parameters:
+         *
+         * m=512   (bits in the filter)
+         * k=8     (hash functions)
+         *
+         * We calculate a single 128bit MurmurHash value of which we
+         * use 8 parts of 9 bits as individual hash functions.
+         *
+         */
+
+        MurmurHash3_x64_128(data, n, 0, hash);
+
+        assert_cc(BLOOM_SIZE*8 == 512);
+
+        for (k = 0; k < ELEMENTSOF(hash); k++)
+                set_bit(filter, hash[k] & 511);
+}
+
+void bloom_add_pair(uint64_t filter[BLOOM_SIZE/8], const char *a, const char *b) {
+        size_t n;
+        char *c;
+
+        assert(filter);
+        assert(a);
+        assert(b);
+
+        n = strlen(a) + 1 + strlen(b);
+        c = alloca(n + 1);
+        strcpy(stpcpy(stpcpy(c, a), ":"), b);
+
+        bloom_add_data(filter, c, n);
+}
+
+void bloom_add_prefixes(uint64_t filter[BLOOM_SIZE/8], const char *a, const char *b, char sep) {
+        size_t n;
+        char *c, *p;
+
+        assert(filter);
+        assert(a);
+        assert(b);
+
+        n = strlen(a) + 1 + strlen(b);
+        c = alloca(n + 1);
+
+        p = stpcpy(stpcpy(c, a), ":");
+        strcpy(p, b);
+
+        for (;;) {
+                char *e;
+
+                e = strrchr(p, sep);
+                if (!e || e == p)
+                        break;
+
+                *e = 0;
+                bloom_add_data(filter, c, e - c);
+        }
+}
diff --git a/src/libsystemd-bus/bus-bloom.h b/src/libsystemd-bus/bus-bloom.h
new file mode 100644
index 0000000000..1bf14a3331
--- /dev/null
+++ b/src/libsystemd-bus/bus-bloom.h
@@ -0,0 +1,30 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+
+#define BLOOM_SIZE 64
+
+void bloom_add_data(uint64_t filter[BLOOM_SIZE/8], const void *data, size_t n);
+void bloom_add_pair(uint64_t filter[BLOOM_SIZE/8], const char *a, const char *b);
+void bloom_add_prefixes(uint64_t filter[BLOOM_SIZE/8], const char *a, const char *b, char sep);
diff --git a/src/libsystemd-bus/bus-internal.c b/src/libsystemd-bus/bus-internal.c
index 3271354600..0e66f3d355 100644
--- a/src/libsystemd-bus/bus-internal.c
+++ b/src/libsystemd-bus/bus-internal.c
@@ -241,3 +241,16 @@ int bus_message_type_from_string(const char *s, uint8_t *u) {
 
         return 0;
 }
+
+const char *bus_message_type_to_string(uint8_t u) {
+        if (u == SD_BUS_MESSAGE_TYPE_SIGNAL)
+                return "signal";
+        else if (u == SD_BUS_MESSAGE_TYPE_METHOD_CALL)
+                return "method_call";
+        else if (u == SD_BUS_MESSAGE_TYPE_METHOD_ERROR)
+                return "error";
+        else if (u == SD_BUS_MESSAGE_TYPE_METHOD_RETURN)
+                 return "method_return";
+        else
+                return NULL;
+}
diff --git a/src/libsystemd-bus/bus-internal.h b/src/libsystemd-bus/bus-internal.h
index 9a118f8a21..4babfac86d 100644
--- a/src/libsystemd-bus/bus-internal.h
+++ b/src/libsystemd-bus/bus-internal.h
@@ -150,8 +150,6 @@ struct sd_bus {
 
         uint64_t hello_serial;
         unsigned iteration_counter;
-
-        uint64_t bloom_size;
 };
 
 static inline void bus_unrefp(sd_bus **b) {
@@ -191,6 +189,7 @@ bool namespace_simple_pattern(const char *pattern, const char *value);
 bool path_simple_pattern(const char *pattern, const char *value);
 
 int bus_message_type_from_string(const char *s, uint8_t *u);
+const char *bus_message_type_to_string(uint8_t u);
 
 #define error_name_is_valid interface_name_is_valid
 
diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c
index 264c6994d9..f36f60e496 100644
--- a/src/libsystemd-bus/bus-kernel.c
+++ b/src/libsystemd-bus/bus-kernel.c
@@ -30,6 +30,7 @@
 #include "bus-internal.h"
 #include "bus-message.h"
 #include "bus-kernel.h"
+#include "bus-bloom.h"
 
 #define KDBUS_MSG_FOREACH_DATA(d, k)                                    \
         for ((d) = (k)->data;                                           \
@@ -80,17 +81,83 @@ static void append_destination(struct kdbus_msg_data **d, const char *s, size_t
         *d = (struct kdbus_msg_data*) ((uint8_t*) *d + (*d)->size);
 }
 
-static void append_bloom(struct kdbus_msg_data **d, const void *p, size_t length) {
+static void* append_bloom(struct kdbus_msg_data **d, size_t length) {
+        void *r;
+
         assert(d);
-        assert(p);
 
         *d = ALIGN8_PTR(*d);
 
         (*d)->size = offsetof(struct kdbus_msg_data, data) + length;
         (*d)->type = KDBUS_MSG_BLOOM;
-        memcpy((*d)->data, p, length);
+        r = (*d)->data;
 
         *d = (struct kdbus_msg_data*) ((uint8_t*) *d + (*d)->size);
+
+        return r;
+}
+
+static int bus_message_setup_bloom(sd_bus_message *m, void *bloom) {
+        unsigned i;
+        int r;
+
+        assert(m);
+        assert(bloom);
+
+        memset(bloom, 0, BLOOM_SIZE);
+
+        bloom_add_pair(bloom, "message-type", bus_message_type_to_string(m->header->type));
+
+        if (m->interface)
+                bloom_add_pair(bloom, "interface", m->interface);
+        if (m->member)
+                bloom_add_pair(bloom, "member", m->member);
+        if (m->path) {
+                bloom_add_pair(bloom, "path", m->path);
+                bloom_add_prefixes(bloom, "path-slash-prefix", m->path, '/');
+        }
+
+        r = sd_bus_message_rewind(m, true);
+        if (r < 0)
+                return r;
+
+        for (i = 0; i < 64; i++) {
+                char type;
+                const char *t;
+                char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
+                char *e;
+
+                r = sd_bus_message_peek_type(m, &type, NULL);
+                if (r < 0)
+                        return r;
+
+                if (type != SD_BUS_TYPE_STRING &&
+                    type != SD_BUS_TYPE_OBJECT_PATH &&
+                    type != SD_BUS_TYPE_SIGNATURE)
+                        break;
+
+                r = sd_bus_message_read_basic(m, type, &t);
+                if (r < 0)
+                        return r;
+
+                e = stpcpy(buf, "arg");
+                if (i < 10)
+                        *(e++) = '0' + i;
+                else {
+                        *(e++) = '0' + (i / 10);
+                        *(e++) = '0' + (i % 10);
+                }
+
+                *e = 0;
+                bloom_add_pair(bloom, buf, t);
+
+                strcpy(e, "-dot-prefix");
+                bloom_add_prefixes(bloom, buf, t, '.');
+                strcpy(e, "-slash-prefix");
+                bloom_add_prefixes(bloom, buf, t, '/');
+        }
+
+        return 0;
 }
 
 static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
@@ -122,7 +189,7 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
         sz += 3 * ALIGN8(offsetof(struct kdbus_msg_data, vec) + sizeof(struct kdbus_vec));
 
         /* Add space for bloom filter */
-        sz += ALIGN8(offsetof(struct kdbus_msg_data, data) + b->bloom_size);
+        sz += ALIGN8(offsetof(struct kdbus_msg_data, data) + BLOOM_SIZE);
 
         /* Add in well-known destination header */
         if (well_known) {
@@ -164,9 +231,13 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
                 void *p;
 
                 /* For now, let's add a mask all bloom filter */
-                p = alloca(b->bloom_size);
-                memset(p, 0xFF, b->bloom_size);
-                append_bloom(&d, p, b->bloom_size);
+                p = append_bloom(&d, BLOOM_SIZE);
+                r = bus_message_setup_bloom(m, p);
+                if (r < 0) {
+                        free(m->kdbus);
+                        m->kdbus = NULL;
+                        return -r;
+                }
         }
 
         m->kdbus->size = (uint8_t*) d - (uint8_t*) m->kdbus;
@@ -207,10 +278,12 @@ int bus_kernel_take_fd(sd_bus *b) {
             hello.conn_flags > 0xFFFFFFFFULL)
                 return -ENOTSUP;
 
+        if (hello.bloom_size != BLOOM_SIZE)
+                return -ENOTSUP;
+
         if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello.id) < 0)
                 return -ENOMEM;
 
-        b->bloom_size = hello.bloom_size;
         b->is_kernel = true;
         b->bus_client = true;
 
@@ -479,7 +552,9 @@ int bus_kernel_create(const char *name, char **s) {
         make->size = offsetof(struct kdbus_cmd_bus_make, name) + strlen(make->name) + 1;
         make->flags = KDBUS_ACCESS_WORLD | KDBUS_POLICY_OPEN;
         make->bus_flags = 0;
-        make->bloom_size = 16;
+        make->bloom_size = BLOOM_SIZE;
+
+        assert_cc(BLOOM_SIZE % 8 == 0);
 
         p = strjoin("/dev/kdbus/", make->name, "/bus", NULL);
         if (!p)
diff --git a/src/libsystemd-bus/test-bus-kernel.c b/src/libsystemd-bus/test-bus-kernel.c
index 2164daf690..5a5d9fc252 100644
--- a/src/libsystemd-bus/test-bus-kernel.c
+++ b/src/libsystemd-bus/test-bus-kernel.c
@@ -71,7 +71,7 @@ int main(int argc, char *argv[]) {
 
         printf("unique b: %s\n", ub);
 
-        r = sd_bus_emit_signal(a, "/foo", "waldo.com", "Piep", "s", "I am a string");
+        r = sd_bus_emit_signal(a, "/foo/bar/waldo", "waldo.com", "Piep", "sss", "I am a string", "/this/is/a/path", "and.this.a.domain.name");
         assert_se(r >= 0);
 
         r = sd_bus_process(b, &m);
diff --git a/src/shared/MurmurHash3.c b/src/shared/MurmurHash3.c
new file mode 100644
index 0000000000..dc56f6b0fb
--- /dev/null
+++ b/src/shared/MurmurHash3.c
@@ -0,0 +1,349 @@
+//-----------------------------------------------------------------------------
+// MurmurHash3 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+
+// Note - The x86 and x64 versions do _not_ produce the same results, as the
+// algorithms are optimized for their respective platforms. You can still
+// compile and run any of them on any platform, but your performance with the
+// non-native version will be less than optimal.
+
+#include "MurmurHash3.h"
+
+//-----------------------------------------------------------------------------
+// Platform-specific functions and macros
+
+// Microsoft Visual Studio
+
+#if defined(_MSC_VER)
+
+#define FORCE_INLINE	__forceinline
+
+#include <stdlib.h>
+
+#define ROTL32(x,y)	_rotl(x,y)
+#define ROTL64(x,y)	_rotl64(x,y)
+
+#define BIG_CONSTANT(x) (x)
+
+// Other compilers
+
+#else	// defined(_MSC_VER)
+
+#define	FORCE_INLINE __attribute__((always_inline))
+
+static inline uint32_t rotl32 ( uint32_t x, int8_t r )
+{
+  return (x << r) | (x >> (32 - r));
+}
+
+static inline uint64_t rotl64 ( uint64_t x, int8_t r )
+{
+  return (x << r) | (x >> (64 - r));
+}
+
+#define	ROTL32(x,y)	rotl32(x,y)
+#define ROTL64(x,y)	rotl64(x,y)
+
+#define BIG_CONSTANT(x) (x##LLU)
+
+#endif // !defined(_MSC_VER)
+
+//-----------------------------------------------------------------------------
+// Block read - if your platform needs to do endian-swapping or can only
+// handle aligned reads, do the conversion here
+
+static FORCE_INLINE uint32_t getblock32 ( const uint32_t * p, int i )
+{
+  return p[i];
+}
+
+static FORCE_INLINE uint64_t getblock64 ( const uint64_t * p, int i )
+{
+  return p[i];
+}
+
+//-----------------------------------------------------------------------------
+// Finalization mix - force all bits of a hash block to avalanche
+
+static FORCE_INLINE uint32_t fmix32 ( uint32_t h )
+{
+  h ^= h >> 16;
+  h *= 0x85ebca6b;
+  h ^= h >> 13;
+  h *= 0xc2b2ae35;
+  h ^= h >> 16;
+
+  return h;
+}
+
+//----------
+
+static FORCE_INLINE uint64_t fmix64 ( uint64_t k )
+{
+  k ^= k >> 33;
+  k *= BIG_CONSTANT(0xff51afd7ed558ccd);
+  k ^= k >> 33;
+  k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);
+  k ^= k >> 33;
+
+  return k;
+}
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x86_32 ( const void * key, size_t len,
+                          uint32_t seed, void * out )
+{
+  const uint8_t * data = (const uint8_t*)key;
+  const int nblocks = len / 4;
+
+  uint32_t h1 = seed;
+
+  const uint32_t c1 = 0xcc9e2d51;
+  const uint32_t c2 = 0x1b873593;
+
+  const uint8_t * tail;
+  uint32_t k1;
+
+  //----------
+  // body
+
+  const uint32_t * blocks = (const uint32_t *)(data + nblocks*4);
+
+  for(int i = -nblocks; i; i++)
+  {
+    k1 = getblock32(blocks,i);
+
+    k1 *= c1;
+    k1 = ROTL32(k1,15);
+    k1 *= c2;
+
+    h1 ^= k1;
+    h1 = ROTL32(h1,13);
+    h1 = h1*5+0xe6546b64;
+  }
+
+  //----------
+  // tail
+
+  tail = (const uint8_t*)(data + nblocks*4);
+
+  k1 = 0;
+
+  switch(len & 3)
+  {
+  case 3: k1 ^= tail[2] << 16;
+  case 2: k1 ^= tail[1] << 8;
+  case 1: k1 ^= tail[0];
+          k1 *= c1; k1 = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
+  };
+
+  //----------
+  // finalization
+
+  h1 ^= len;
+
+  h1 = fmix32(h1);
+
+  *(uint32_t*)out = h1;
+}
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x86_128 ( const void * key, const size_t len,
+                           uint32_t seed, void * out )
+{
+  const uint8_t * data = (const uint8_t*)key;
+  const int nblocks = len / 16;
+
+  uint32_t h1 = seed;
+  uint32_t h2 = seed;
+  uint32_t h3 = seed;
+  uint32_t h4 = seed;
+
+  const uint32_t c1 = 0x239b961b;
+  const uint32_t c2 = 0xab0e9789;
+  const uint32_t c3 = 0x38b34ae5;
+  const uint32_t c4 = 0xa1e38b93;
+
+  const uint8_t * tail;
+
+  uint32_t k1;
+  uint32_t k2;
+  uint32_t k3;
+  uint32_t k4;
+
+  //----------
+  // body
+
+  const uint32_t * blocks = (const uint32_t *)(data + nblocks*16);
+
+  for(int i = -nblocks; i; i++)
+  {
+    k1 = getblock32(blocks,i*4+0);
+    k2 = getblock32(blocks,i*4+1);
+    k3 = getblock32(blocks,i*4+2);
+    k4 = getblock32(blocks,i*4+3);
+
+    k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
+
+    h1 = ROTL32(h1,19); h1 += h2; h1 = h1*5+0x561ccd1b;
+
+    k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;
+
+    h2 = ROTL32(h2,17); h2 += h3; h2 = h2*5+0x0bcaa747;
+
+    k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;
+
+    h3 = ROTL32(h3,15); h3 += h4; h3 = h3*5+0x96cd1c35;
+
+    k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;
+
+    h4 = ROTL32(h4,13); h4 += h1; h4 = h4*5+0x32ac3b17;
+  }
+
+  //----------
+  // tail
+
+  tail = (const uint8_t*)(data + nblocks*16);
+
+  k1 = 0;
+  k2 = 0;
+  k3 = 0;
+  k4 = 0;
+
+  switch(len & 15)
+  {
+  case 15: k4 ^= tail[14] << 16;
+  case 14: k4 ^= tail[13] << 8;
+  case 13: k4 ^= tail[12] << 0;
+           k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;
+
+  case 12: k3 ^= tail[11] << 24;
+  case 11: k3 ^= tail[10] << 16;
+  case 10: k3 ^= tail[ 9] << 8;
+  case  9: k3 ^= tail[ 8] << 0;
+           k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;
+
+  case  8: k2 ^= tail[ 7] << 24;
+  case  7: k2 ^= tail[ 6] << 16;
+  case  6: k2 ^= tail[ 5] << 8;
+  case  5: k2 ^= tail[ 4] << 0;
+           k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;
+
+  case  4: k1 ^= tail[ 3] << 24;
+  case  3: k1 ^= tail[ 2] << 16;
+  case  2: k1 ^= tail[ 1] << 8;
+  case  1: k1 ^= tail[ 0] << 0;
+           k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
+  };
+
+  //----------
+  // finalization
+
+  h1 ^= len; h2 ^= len; h3 ^= len; h4 ^= len;
+
+  h1 += h2; h1 += h3; h1 += h4;
+  h2 += h1; h3 += h1; h4 += h1;
+
+  h1 = fmix32(h1);
+  h2 = fmix32(h2);
+  h3 = fmix32(h3);
+  h4 = fmix32(h4);
+
+  h1 += h2; h1 += h3; h1 += h4;
+  h2 += h1; h3 += h1; h4 += h1;
+
+  ((uint32_t*)out)[0] = h1;
+  ((uint32_t*)out)[1] = h2;
+  ((uint32_t*)out)[2] = h3;
+  ((uint32_t*)out)[3] = h4;
+}
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x64_128 ( const void * key, const size_t len,
+                           const uint32_t seed, void * out )
+{
+  const uint8_t * data = (const uint8_t*)key;
+  const int nblocks = len / 16;
+
+  uint64_t h1 = seed;
+  uint64_t h2 = seed;
+
+  const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
+  const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);
+
+  const uint8_t *tail;
+
+  uint64_t k1;
+  uint64_t k2;
+
+  //----------
+  // body
+
+  const uint64_t * blocks = (const uint64_t *)(data);
+
+  for(int i = 0; i < nblocks; i++)
+  {
+    k1 = getblock64(blocks,i*2+0);
+    k2 = getblock64(blocks,i*2+1);
+
+    k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
+
+    h1 = ROTL64(h1,27); h1 += h2; h1 = h1*5+0x52dce729;
+
+    k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;
+
+    h2 = ROTL64(h2,31); h2 += h1; h2 = h2*5+0x38495ab5;
+  }
+
+  //----------
+  // tail
+
+  tail = (const uint8_t*)(data + nblocks*16);
+
+  k1 = 0;
+  k2 = 0;
+
+  switch(len & 15)
+  {
+  case 15: k2 ^= (uint64_t)(tail[14]) << 48;
+  case 14: k2 ^= (uint64_t)(tail[13]) << 40;
+  case 13: k2 ^= (uint64_t)(tail[12]) << 32;
+  case 12: k2 ^= (uint64_t)(tail[11]) << 24;
+  case 11: k2 ^= (uint64_t)(tail[10]) << 16;
+  case 10: k2 ^= (uint64_t)(tail[ 9]) << 8;
+  case  9: k2 ^= (uint64_t)(tail[ 8]) << 0;
+           k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;
+
+  case  8: k1 ^= (uint64_t)(tail[ 7]) << 56;
+  case  7: k1 ^= (uint64_t)(tail[ 6]) << 48;
+  case  6: k1 ^= (uint64_t)(tail[ 5]) << 40;
+  case  5: k1 ^= (uint64_t)(tail[ 4]) << 32;
+  case  4: k1 ^= (uint64_t)(tail[ 3]) << 24;
+  case  3: k1 ^= (uint64_t)(tail[ 2]) << 16;
+  case  2: k1 ^= (uint64_t)(tail[ 1]) << 8;
+  case  1: k1 ^= (uint64_t)(tail[ 0]) << 0;
+           k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
+  };
+
+  //----------
+  // finalization
+
+  h1 ^= len; h2 ^= len;
+
+  h1 += h2;
+  h2 += h1;
+
+  h1 = fmix64(h1);
+  h2 = fmix64(h2);
+
+  h1 += h2;
+  h2 += h1;
+
+  ((uint64_t*)out)[0] = h1;
+  ((uint64_t*)out)[1] = h2;
+}
+
+//-----------------------------------------------------------------------------
diff --git a/src/shared/MurmurHash3.h b/src/shared/MurmurHash3.h
new file mode 100644
index 0000000000..07c474eba4
--- /dev/null
+++ b/src/shared/MurmurHash3.h
@@ -0,0 +1,38 @@
+//-----------------------------------------------------------------------------
+// MurmurHash3 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+
+#ifndef _MURMURHASH3_H_
+#define _MURMURHASH3_H_
+
+//-----------------------------------------------------------------------------
+// Platform-specific functions and macros
+
+// Microsoft Visual Studio
+
+#if defined(_MSC_VER)
+
+typedef unsigned char uint8_t;
+typedef unsigned long uint32_t;
+typedef unsigned __int64 uint64_t;
+
+// Other compilers
+
+#else	// defined(_MSC_VER)
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#endif // !defined(_MSC_VER)
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x86_32  ( const void * key, size_t len, uint32_t seed, void * out );
+
+void MurmurHash3_x86_128 ( const void * key, size_t len, uint32_t seed, void * out );
+
+void MurmurHash3_x64_128 ( const void * key, size_t len, uint32_t seed, void * out );
+
+//-----------------------------------------------------------------------------
+
+#endif // _MURMURHASH3_H_