Add linux-next specific files for 20110831
[linux-2.6/next.git] / net / core / secure_seq.c
blob45329d7c9dd9bec432a933804c00ee45fc43bbe4
1 #include <linux/kernel.h>
2 #include <linux/init.h>
3 #include <linux/cryptohash.h>
4 #include <linux/module.h>
5 #include <linux/cache.h>
6 #include <linux/random.h>
7 #include <linux/hrtimer.h>
8 #include <linux/ktime.h>
9 #include <linux/string.h>
11 #include <net/secure_seq.h>
13 static u32 net_secret[MD5_MESSAGE_BYTES / 4] ____cacheline_aligned;
15 static int __init net_secret_init(void)
17 get_random_bytes(net_secret, sizeof(net_secret));
18 return 0;
20 late_initcall(net_secret_init);
22 static u32 seq_scale(u32 seq)
25 * As close as possible to RFC 793, which
26 * suggests using a 250 kHz clock.
27 * Further reading shows this assumes 2 Mb/s networks.
28 * For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
29 * For 10 Gb/s Ethernet, a 1 GHz clock should be ok, but
30 * we also need to limit the resolution so that the u32 seq
31 * overlaps less than one time per MSL (2 minutes).
32 * Choosing a clock of 64 ns period is OK. (period of 274 s)
34 return seq + (ktime_to_ns(ktime_get_real()) >> 6);
37 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
38 __u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr,
39 __be16 sport, __be16 dport)
41 u32 secret[MD5_MESSAGE_BYTES / 4];
42 u32 hash[MD5_DIGEST_WORDS];
43 u32 i;
45 memcpy(hash, saddr, 16);
46 for (i = 0; i < 4; i++)
47 secret[i] = net_secret[i] + daddr[i];
48 secret[4] = net_secret[4] +
49 (((__force u16)sport << 16) + (__force u16)dport);
50 for (i = 5; i < MD5_MESSAGE_BYTES / 4; i++)
51 secret[i] = net_secret[i];
53 md5_transform(hash, secret);
55 return seq_scale(hash[0]);
57 EXPORT_SYMBOL(secure_tcpv6_sequence_number);
59 u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,
60 __be16 dport)
62 u32 secret[MD5_MESSAGE_BYTES / 4];
63 u32 hash[MD5_DIGEST_WORDS];
64 u32 i;
66 memcpy(hash, saddr, 16);
67 for (i = 0; i < 4; i++)
68 secret[i] = net_secret[i] + (__force u32) daddr[i];
69 secret[4] = net_secret[4] + (__force u32)dport;
70 for (i = 5; i < MD5_MESSAGE_BYTES / 4; i++)
71 secret[i] = net_secret[i];
73 md5_transform(hash, secret);
75 return hash[0];
77 #endif
79 #ifdef CONFIG_INET
80 __u32 secure_ip_id(__be32 daddr)
82 u32 hash[MD5_DIGEST_WORDS];
84 hash[0] = (__force __u32) daddr;
85 hash[1] = net_secret[13];
86 hash[2] = net_secret[14];
87 hash[3] = net_secret[15];
89 md5_transform(hash, net_secret);
91 return hash[0];
94 __u32 secure_ipv6_id(const __be32 daddr[4])
96 __u32 hash[4];
98 memcpy(hash, daddr, 16);
99 md5_transform(hash, net_secret);
101 return hash[0];
104 __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
105 __be16 sport, __be16 dport)
107 u32 hash[MD5_DIGEST_WORDS];
109 hash[0] = (__force u32)saddr;
110 hash[1] = (__force u32)daddr;
111 hash[2] = ((__force u16)sport << 16) + (__force u16)dport;
112 hash[3] = net_secret[15];
114 md5_transform(hash, net_secret);
116 return seq_scale(hash[0]);
119 u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
121 u32 hash[MD5_DIGEST_WORDS];
123 hash[0] = (__force u32)saddr;
124 hash[1] = (__force u32)daddr;
125 hash[2] = (__force u32)dport ^ net_secret[14];
126 hash[3] = net_secret[15];
128 md5_transform(hash, net_secret);
130 return hash[0];
132 EXPORT_SYMBOL_GPL(secure_ipv4_port_ephemeral);
133 #endif
135 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
136 u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
137 __be16 sport, __be16 dport)
139 u32 hash[MD5_DIGEST_WORDS];
140 u64 seq;
142 hash[0] = (__force u32)saddr;
143 hash[1] = (__force u32)daddr;
144 hash[2] = ((__force u16)sport << 16) + (__force u16)dport;
145 hash[3] = net_secret[15];
147 md5_transform(hash, net_secret);
149 seq = hash[0] | (((u64)hash[1]) << 32);
150 seq += ktime_to_ns(ktime_get_real());
151 seq &= (1ull << 48) - 1;
153 return seq;
155 EXPORT_SYMBOL(secure_dccp_sequence_number);
157 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
158 u64 secure_dccpv6_sequence_number(__be32 *saddr, __be32 *daddr,
159 __be16 sport, __be16 dport)
161 u32 secret[MD5_MESSAGE_BYTES / 4];
162 u32 hash[MD5_DIGEST_WORDS];
163 u64 seq;
164 u32 i;
166 memcpy(hash, saddr, 16);
167 for (i = 0; i < 4; i++)
168 secret[i] = net_secret[i] + daddr[i];
169 secret[4] = net_secret[4] +
170 (((__force u16)sport << 16) + (__force u16)dport);
171 for (i = 5; i < MD5_MESSAGE_BYTES / 4; i++)
172 secret[i] = net_secret[i];
174 md5_transform(hash, secret);
176 seq = hash[0] | (((u64)hash[1]) << 32);
177 seq += ktime_to_ns(ktime_get_real());
178 seq &= (1ull << 48) - 1;
180 return seq;
182 EXPORT_SYMBOL(secure_dccpv6_sequence_number);
183 #endif
184 #endif