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authorLinus Torvalds <torvalds@linux-foundation.org>2014-08-06 09:38:14 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-08-06 09:38:14 -0700
commitae045e2455429c418a418a3376301a9e5753a0a8 (patch)
treeb445bdeecd3f38aa0d0a29c9585cee49e4ccb0f1 /lib/random32.c
parentf4f142ed4ef835709c7e6d12eaca10d190bcebed (diff)
parentd247b6ab3ce6dd43665780865ec5fa145d9ab6bd (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: "Highlights: 1) Steady transitioning of the BPF instructure to a generic spot so all kernel subsystems can make use of it, from Alexei Starovoitov. 2) SFC driver supports busy polling, from Alexandre Rames. 3) Take advantage of hash table in UDP multicast delivery, from David Held. 4) Lighten locking, in particular by getting rid of the LRU lists, in inet frag handling. From Florian Westphal. 5) Add support for various RFC6458 control messages in SCTP, from Geir Ola Vaagland. 6) Allow to filter bridge forwarding database dumps by device, from Jamal Hadi Salim. 7) virtio-net also now supports busy polling, from Jason Wang. 8) Some low level optimization tweaks in pktgen from Jesper Dangaard Brouer. 9) Add support for ipv6 address generation modes, so that userland can have some input into the process. From Jiri Pirko. 10) Consolidate common TCP connection request code in ipv4 and ipv6, from Octavian Purdila. 11) New ARP packet logger in netfilter, from Pablo Neira Ayuso. 12) Generic resizable RCU hash table, with intial users in netlink and nftables. From Thomas Graf. 13) Maintain a name assignment type so that userspace can see where a network device name came from (enumerated by kernel, assigned explicitly by userspace, etc.) From Tom Gundersen. 14) Automatic flow label generation on transmit in ipv6, from Tom Herbert. 15) New packet timestamping facilities from Willem de Bruijn, meant to assist in measuring latencies going into/out-of the packet scheduler, latency from TCP data transmission to ACK, etc" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits) cxgb4 : Disable recursive mailbox commands when enabling vi net: reduce USB network driver config options. tg3: Modify tg3_tso_bug() to handle multiple TX rings amd-xgbe: Perform phy connect/disconnect at dev open/stop amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask net: sun4i-emac: fix memory leak on bad packet sctp: fix possible seqlock seadlock in sctp_packet_transmit() Revert "net: phy: Set the driver when registering an MDIO bus device" cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine team: Simplify return path of team_newlink bridge: Update outdated comment on promiscuous mode net-timestamp: ACK timestamp for bytestreams net-timestamp: TCP timestamping net-timestamp: SCHED timestamp on entering packet scheduler net-timestamp: add key to disambiguate concurrent datagrams net-timestamp: move timestamp flags out of sk_flags net-timestamp: extend SCM_TIMESTAMPING ancillary data struct cxgb4i : Move stray CPL definitions to cxgb4 driver tcp: reduce spurious retransmits due to transient SACK reneging qlcnic: Initialize dcbnl_ops before register_netdev ...
Diffstat (limited to 'lib/random32.c')
-rw-r--r--lib/random32.c49
1 files changed, 28 insertions, 21 deletions
diff --git a/lib/random32.c b/lib/random32.c
index fa5da61ce7ad..c9b6bf3afe0c 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -40,6 +40,10 @@
#ifdef CONFIG_RANDOM32_SELFTEST
static void __init prandom_state_selftest(void);
+#else
+static inline void prandom_state_selftest(void)
+{
+}
#endif
static DEFINE_PER_CPU(struct rnd_state, net_rand_state);
@@ -53,8 +57,7 @@ static DEFINE_PER_CPU(struct rnd_state, net_rand_state);
*/
u32 prandom_u32_state(struct rnd_state *state)
{
-#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
-
+#define TAUSWORTHE(s, a, b, c, d) ((s & c) << d) ^ (((s << a) ^ s) >> b)
state->s1 = TAUSWORTHE(state->s1, 6U, 13U, 4294967294U, 18U);
state->s2 = TAUSWORTHE(state->s2, 2U, 27U, 4294967288U, 2U);
state->s3 = TAUSWORTHE(state->s3, 13U, 21U, 4294967280U, 7U);
@@ -147,21 +150,25 @@ static void prandom_warmup(struct rnd_state *state)
prandom_u32_state(state);
}
-static void prandom_seed_very_weak(struct rnd_state *state, u32 seed)
+static u32 __extract_hwseed(void)
{
- /* Note: This sort of seeding is ONLY used in test cases and
- * during boot at the time from core_initcall until late_initcall
- * as we don't have a stronger entropy source available yet.
- * After late_initcall, we reseed entire state, we have to (!),
- * otherwise an attacker just needs to search 32 bit space to
- * probe for our internal 128 bit state if he knows a couple
- * of prandom32 outputs!
- */
-#define LCG(x) ((x) * 69069U) /* super-duper LCG */
- state->s1 = __seed(LCG(seed), 2U);
- state->s2 = __seed(LCG(state->s1), 8U);
- state->s3 = __seed(LCG(state->s2), 16U);
- state->s4 = __seed(LCG(state->s3), 128U);
+ u32 val = 0;
+
+ (void)(arch_get_random_seed_int(&val) ||
+ arch_get_random_int(&val));
+
+ return val;
+}
+
+static void prandom_seed_early(struct rnd_state *state, u32 seed,
+ bool mix_with_hwseed)
+{
+#define LCG(x) ((x) * 69069U) /* super-duper LCG */
+#define HWSEED() (mix_with_hwseed ? __extract_hwseed() : 0)
+ state->s1 = __seed(HWSEED() ^ LCG(seed), 2U);
+ state->s2 = __seed(HWSEED() ^ LCG(state->s1), 8U);
+ state->s3 = __seed(HWSEED() ^ LCG(state->s2), 16U);
+ state->s4 = __seed(HWSEED() ^ LCG(state->s3), 128U);
}
/**
@@ -194,14 +201,13 @@ static int __init prandom_init(void)
{
int i;
-#ifdef CONFIG_RANDOM32_SELFTEST
prandom_state_selftest();
-#endif
for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state,i);
+ u32 weak_seed = (i + jiffies) ^ random_get_entropy();
- prandom_seed_very_weak(state, (i + jiffies) ^ random_get_entropy());
+ prandom_seed_early(state, weak_seed, true);
prandom_warmup(state);
}
@@ -210,6 +216,7 @@ static int __init prandom_init(void)
core_initcall(prandom_init);
static void __prandom_timer(unsigned long dontcare);
+
static DEFINE_TIMER(seed_timer, __prandom_timer, 0, 0);
static void __prandom_timer(unsigned long dontcare)
@@ -419,7 +426,7 @@ static void __init prandom_state_selftest(void)
for (i = 0; i < ARRAY_SIZE(test1); i++) {
struct rnd_state state;
- prandom_seed_very_weak(&state, test1[i].seed);
+ prandom_seed_early(&state, test1[i].seed, false);
prandom_warmup(&state);
if (test1[i].result != prandom_u32_state(&state))
@@ -434,7 +441,7 @@ static void __init prandom_state_selftest(void)
for (i = 0; i < ARRAY_SIZE(test2); i++) {
struct rnd_state state;
- prandom_seed_very_weak(&state, test2[i].seed);
+ prandom_seed_early(&state, test2[i].seed, false);
prandom_warmup(&state);
for (j = 0; j < test2[i].iteration - 1; j++)