diff options
Diffstat (limited to 'net/core/secure_seq.c')
| -rw-r--r-- | net/core/secure_seq.c | 44 |
1 files changed, 35 insertions, 9 deletions
diff --git a/net/core/secure_seq.c b/net/core/secure_seq.c index 758f140b6bed..6bd2f8fb0476 100644 --- a/net/core/secure_seq.c +++ b/net/core/secure_seq.c @@ -20,9 +20,11 @@ #include <net/tcp.h> static siphash_key_t net_secret __read_mostly; +static siphash_key_t ts_secret __read_mostly; static __always_inline void net_secret_init(void) { + net_get_random_once(&ts_secret, sizeof(ts_secret)); net_get_random_once(&net_secret, sizeof(net_secret)); } #endif @@ -45,8 +47,25 @@ static u32 seq_scale(u32 seq) #endif #if IS_ENABLED(CONFIG_IPV6) -u32 secure_tcpv6_sequence_number(const __be32 *saddr, const __be32 *daddr, - __be16 sport, __be16 dport, u32 *tsoff) +static u32 secure_tcpv6_ts_off(const __be32 *saddr, const __be32 *daddr) +{ + const struct { + struct in6_addr saddr; + struct in6_addr daddr; + } __aligned(SIPHASH_ALIGNMENT) combined = { + .saddr = *(struct in6_addr *)saddr, + .daddr = *(struct in6_addr *)daddr, + }; + + if (sysctl_tcp_timestamps != 1) + return 0; + + return siphash(&combined, offsetofend(typeof(combined), daddr), + &ts_secret); +} + +u32 secure_tcpv6_seq_and_tsoff(const __be32 *saddr, const __be32 *daddr, + __be16 sport, __be16 dport, u32 *tsoff) { const struct { struct in6_addr saddr; @@ -63,10 +82,10 @@ u32 secure_tcpv6_sequence_number(const __be32 *saddr, const __be32 *daddr, net_secret_init(); hash = siphash(&combined, offsetofend(typeof(combined), dport), &net_secret); - *tsoff = sysctl_tcp_timestamps == 1 ? (hash >> 32) : 0; + *tsoff = secure_tcpv6_ts_off(saddr, daddr); return seq_scale(hash); } -EXPORT_SYMBOL(secure_tcpv6_sequence_number); +EXPORT_SYMBOL(secure_tcpv6_seq_and_tsoff); u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, __be16 dport) @@ -88,22 +107,29 @@ EXPORT_SYMBOL(secure_ipv6_port_ephemeral); #endif #ifdef CONFIG_INET +static u32 secure_tcp_ts_off(__be32 saddr, __be32 daddr) +{ + if (sysctl_tcp_timestamps != 1) + return 0; -/* secure_tcp_sequence_number(a, b, 0, d) == secure_ipv4_port_ephemeral(a, b, d), + return siphash_2u32((__force u32)saddr, (__force u32)daddr, + &ts_secret); +} + +/* secure_tcp_seq_and_tsoff(a, b, 0, d) == secure_ipv4_port_ephemeral(a, b, d), * but fortunately, `sport' cannot be 0 in any circumstances. If this changes, * it would be easy enough to have the former function use siphash_4u32, passing * the arguments as separate u32. */ - -u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr, - __be16 sport, __be16 dport, u32 *tsoff) +u32 secure_tcp_seq_and_tsoff(__be32 saddr, __be32 daddr, + __be16 sport, __be16 dport, u32 *tsoff) { u64 hash; net_secret_init(); hash = siphash_3u32((__force u32)saddr, (__force u32)daddr, (__force u32)sport << 16 | (__force u32)dport, &net_secret); - *tsoff = sysctl_tcp_timestamps == 1 ? (hash >> 32) : 0; + *tsoff = secure_tcp_ts_off(saddr, daddr); return seq_scale(hash); } |