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/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
#ifdef DEBUG
#include <linux/jiffies.h>
static const struct { bool result; unsigned int msec_to_sleep_before; } expected_results[] __initconst = {
[0 ... PACKETS_BURSTABLE - 1] = { true, 0 },
[PACKETS_BURSTABLE] = { false, 0 },
[PACKETS_BURSTABLE + 1] = { true, MSEC_PER_SEC / PACKETS_PER_SECOND },
[PACKETS_BURSTABLE + 2] = { false, 0 },
[PACKETS_BURSTABLE + 3] = { true, (MSEC_PER_SEC / PACKETS_PER_SECOND) * 2 },
[PACKETS_BURSTABLE + 4] = { true, 0 },
[PACKETS_BURSTABLE + 5] = { false, 0 }
};
static __init unsigned int maximum_jiffies_at_index(int index)
{
unsigned int total_msecs = 2 * MSEC_PER_SEC / PACKETS_PER_SECOND / 3;
int i;
for (i = 0; i <= index; ++i)
total_msecs += expected_results[i].msec_to_sleep_before;
return msecs_to_jiffies(total_msecs);
}
bool __init ratelimiter_selftest(void)
{
struct sk_buff *skb4;
struct iphdr *hdr4;
#if IS_ENABLED(CONFIG_IPV6)
struct sk_buff *skb6;
struct ipv6hdr *hdr6;
#endif
int i, test = 0, tries = 0, ret = false;
unsigned long loop_start_time;
BUILD_BUG_ON(MSEC_PER_SEC % PACKETS_PER_SECOND != 0);
if (ratelimiter_init())
goto out;
++test;
if (ratelimiter_init()) {
ratelimiter_uninit();
goto out;
}
++test;
if (ratelimiter_init()) {
ratelimiter_uninit();
ratelimiter_uninit();
goto out;
}
++test;
skb4 = alloc_skb(sizeof(struct iphdr), GFP_KERNEL);
if (!skb4)
goto err_nofree;
skb4->protocol = htons(ETH_P_IP);
hdr4 = (struct iphdr *)skb_put(skb4, sizeof(struct iphdr));
hdr4->saddr = htonl(8182);
skb_reset_network_header(skb4);
++test;
#if IS_ENABLED(CONFIG_IPV6)
skb6 = alloc_skb(sizeof(struct ipv6hdr), GFP_KERNEL);
if (!skb6) {
kfree_skb(skb4);
goto err_nofree;
}
skb6->protocol = htons(ETH_P_IPV6);
hdr6 = (struct ipv6hdr *)skb_put(skb6, sizeof(struct ipv6hdr));
hdr6->saddr.in6_u.u6_addr32[0] = htonl(1212);
hdr6->saddr.in6_u.u6_addr32[1] = htonl(289188);
skb_reset_network_header(skb6);
++test;
#endif
restart:
loop_start_time = jiffies;
for (i = 0; i < ARRAY_SIZE(expected_results); ++i) {
#define ensure_time do {\
if (time_is_before_jiffies(loop_start_time + maximum_jiffies_at_index(i))) { \
if (++tries >= 5000) \
goto err; \
gc_entries(NULL); \
rcu_barrier(); \
msleep(500); \
goto restart; \
}} while (0)
if (expected_results[i].msec_to_sleep_before)
msleep(expected_results[i].msec_to_sleep_before);
ensure_time;
if (ratelimiter_allow(skb4, &init_net) != expected_results[i].result)
goto err;
++test;
hdr4->saddr = htonl(ntohl(hdr4->saddr) + i + 1);
ensure_time;
if (!ratelimiter_allow(skb4, &init_net))
goto err;
++test;
hdr4->saddr = htonl(ntohl(hdr4->saddr) - i - 1);
#if IS_ENABLED(CONFIG_IPV6)
hdr6->saddr.in6_u.u6_addr32[2] = hdr6->saddr.in6_u.u6_addr32[3] = htonl(i);
ensure_time;
if (ratelimiter_allow(skb6, &init_net) != expected_results[i].result)
goto err;
++test;
hdr6->saddr.in6_u.u6_addr32[0] = htonl(ntohl(hdr6->saddr.in6_u.u6_addr32[0]) + i + 1);
ensure_time;
if (!ratelimiter_allow(skb6, &init_net))
goto err;
++test;
hdr6->saddr.in6_u.u6_addr32[0] = htonl(ntohl(hdr6->saddr.in6_u.u6_addr32[0]) - i - 1);
ensure_time;
#endif
}
gc_entries(NULL);
rcu_barrier();
if (atomic_read(&total_entries))
goto err;
++test;
for (i = 0; i <= max_entries; ++i) {
hdr4->saddr = htonl(i);
if (ratelimiter_allow(skb4, &init_net) != (i != max_entries))
goto err;
++test;
}
ret = true;
err:
kfree_skb(skb4);
#if IS_ENABLED(CONFIG_IPV6)
kfree_skb(skb6);
#endif
err_nofree:
ratelimiter_uninit();
ratelimiter_uninit();
ratelimiter_uninit();
out:
if (ret)
pr_info("ratelimiter self-tests: pass\n");
else
pr_info("ratelimiter self-test %d: fail\n", test);
return ret;
}
#endif
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