[IPV4]: Always use Jenkins hash in ipvs conn table, use get_random_bytes() to init...

diff --git a/net/ipv4/ipvs/Kconfig b/net/ipv4/ipvs/Kconfig
index 53f2473502d889ac1d8b108a119b70a4754e9000..a6487f20a50b06d4e5d9b3561a27d9084c204ac2 100644 (file)
--- a/net/ipv4/ipvs/Kconfig
+++ b/net/ipv4/ipvs/Kconfig
@@ -62,58 +62,6 @@ config       IP_VS_TAB_BITS
          each hash entry uses 8 bytes, so you can estimate how much memory is
          needed for your box.
 
-choice
-       prompt "IPVS connection hash function"
-       default IP_VS_HASH_JENKINS
-       ---help---
-         IPVS connection hash function is used to hash IPVS connection
-         entries. It takes the protocol, client address and port number
-         <proto, addr, port> (in network order) to compute hash key. 
-         Here you need to choose a hash function to compute hash key.
-         The Jenkins hash is recommended by default.
-
-config IP_VS_HASH_SHIFTXOR
-       bool "SHIFTXOR"
-       ---help---
-         The SHIFTXOR hash function is to compute key in the following way:
-                 key = ntohl(addr) + ip_vs_conn_rnd;
-                 key ^= (key >> IP_VS_CONN_TAB_BITS);
-                 key ^= (key >> 23);
-                 key = proto ^ key ^ ntohs(port)) & IP_VS_CONN_TAB_MASK;
-
-         The random value ip_vs_conn_rnd is introduced to prevent from
-         hash attack.
-
-config IP_VS_HASH_GOLDENRATIO
-       bool "GOLDENRATIO"
-       ---help---
-         In Knuth's "The Art of Computer Programming", section 6.4, a
-         multiplicative hashing scheme is introduced as a way to write hash
-         function. The key is multiplied by the golden ratio of 2^32
-         (2654435761) to produce a hash result. Note that 2654435761 is
-         also a prime number.
-
-         The GOLDENRATIO hash function is to compute connection hash key
-         in the following way:
-                 key = ip_vs_conn_rnd ^ (proto + addr + port);
-                 key = ((key * 2654435761) >> (31 - IP_VS_CONN_TAB_BITS))
-                       & IP_VS_CONN_TAB_MASK;
-
-config IP_VS_HASH_JENKINS
-       bool "JENKINS"
-       ---help---
-         The Jenkins hash support is included in the Linux kernel, the
-         header file is at linux/include/jhash.h. You can read the
-         http://burtleburtle.net/bob/hash/index.html for more information
-         about the Jenkins hash.
-
-         The Jenkins hash function is used to compute connection hash key
-         in the following way:
-                 key = jhash_3words(addr, port, proto, ip_vs_conn_rnd)
-                       & IP_VS_CONN_TAB_MASK;
-
-endchoice
-
 comment "IPVS transport protocol load balancing support"
         depends on IP_VS
 

diff --git a/net/ipv4/ipvs/ip_vs_conn.c b/net/ipv4/ipvs/ip_vs_conn.c
index d200a9b9e62ab52d26939415dc72af4f194ed717..6b8806205f5e01d1e9a532dad138541b77a10b4f 100644 (file)
--- a/net/ipv4/ipvs/ip_vs_conn.c
+++ b/net/ipv4/ipvs/ip_vs_conn.c
@@ -31,6 +31,7 @@
 #include <linux/vmalloc.h>
 #include <linux/proc_fs.h>             /* for proc_net_* */
 #include <linux/jhash.h>
+#include <linux/random.h>
 
 #include <net/ip_vs.h>
 
@@ -112,24 +113,10 @@ static inline void ct_write_unlock_bh(unsigned key)
 /*
  *     Returns hash value for IPVS connection entry
  */
-static inline unsigned
-ip_vs_conn_hashkey(unsigned proto, __u32 addr, __u16 port)
+static unsigned int ip_vs_conn_hashkey(unsigned proto, __u32 addr, __u16 port)
 {
-#ifdef CONFIG_IP_VS_HASH_SHIFTXOR
-       unsigned key = ntohl(addr) + ip_vs_conn_rnd;
-
-       key ^= (key >> IP_VS_CONN_TAB_BITS);
-       key ^= (key >> 23);
-       return (proto ^ key ^ ntohs(port)) & IP_VS_CONN_TAB_MASK;
-#endif
-#ifdef CONFIG_IP_VS_HASH_GOLDENRATIO
-       return (((ip_vs_conn_rnd ^ (proto + addr + port)) * 2654435761UL)
-               >> (31 - IP_VS_CONN_TAB_BITS)) & IP_VS_CONN_TAB_MASK;
-#endif
-#ifdef CONFIG_IP_VS_HASH_JENKINS
        return jhash_3words(addr, port, proto, ip_vs_conn_rnd)
                & IP_VS_CONN_TAB_MASK;
-#endif
 }
 
 
@@ -865,9 +852,7 @@ int ip_vs_conn_init(void)
        proc_net_create("ip_vs_conn", 0, ip_vs_conn_getinfo);
 
        /* calculate the random value for connection hash */
-       ip_vs_conn_rnd =
-               jhash_3words((u32) jiffies, (u32) ip_vs_conn_tab,
-                            net_random(), IP_VS_CONN_TAB_SIZE);
+       get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
 
        return 0;
 }