/* * Copyright (C) 2016 Jason A. Donenfeld . All Rights Reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #if IS_ENABLED(CONFIG_IPV6) || IS_ENABLED(CONFIG_INET) #include #include static siphash_key_t net_secret __read_mostly; static __always_inline void net_secret_init(void) { net_get_random_once(&net_secret, sizeof(net_secret)); } #endif #ifdef CONFIG_INET static u32 seq_scale(u32 seq) { /* * As close as possible to RFC 793, which * suggests using a 250 kHz clock. * Further reading shows this assumes 2 Mb/s networks. * For 10 Mb/s Ethernet, a 1 MHz clock is appropriate. * For 10 Gb/s Ethernet, a 1 GHz clock should be ok, but * we also need to limit the resolution so that the u32 seq * overlaps less than one time per MSL (2 minutes). * Choosing a clock of 64 ns period is OK. (period of 274 s) */ return seq + (ktime_get_real_ns() >> 6); } #endif #if IS_ENABLED(CONFIG_IPV6) u32 secure_tcpv6_sequence_number(const __be32 *saddr, const __be32 *daddr, __be16 sport, __be16 dport, u32 *tsoff) { const struct { struct in6_addr saddr; struct in6_addr daddr; __be16 sport; __be16 dport; } __aligned(SIPHASH_ALIGNMENT) combined = { .saddr = *(struct in6_addr *)saddr, .daddr = *(struct in6_addr *)daddr, .sport = sport, .dport = dport }; u64 hash; net_secret_init(); hash = siphash(&combined, offsetofend(typeof(combined), dport), &net_secret); *tsoff = sysctl_tcp_timestamps == 1 ? (hash >> 32) : 0; return seq_scale(hash); } EXPORT_SYMBOL(secure_tcpv6_sequence_number); u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, __be16 dport) { const struct { struct in6_addr saddr; struct in6_addr daddr; __be16 dport; } __aligned(SIPHASH_ALIGNMENT) combined = { .saddr = *(struct in6_addr *)saddr, .daddr = *(struct in6_addr *)daddr, .dport = dport }; net_secret_init(); return siphash(&combined, offsetofend(typeof(combined), dport), &net_secret); } EXPORT_SYMBOL(secure_ipv6_port_ephemeral); #endif #ifdef CONFIG_INET /* secure_tcp_sequence_number(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) { 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; return seq_scale(hash); } u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport) { net_secret_init(); return siphash_3u32((__force u32)saddr, (__force u32)daddr, (__force u16)dport, &net_secret); } EXPORT_SYMBOL_GPL(secure_ipv4_port_ephemeral); #endif #if IS_ENABLED(CONFIG_IP_DCCP) u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport) { u64 seq; net_secret_init(); seq = siphash_3u32((__force u32)saddr, (__force u32)daddr, (__force u32)sport << 16 | (__force u32)dport, &net_secret); seq += ktime_get_real_ns(); seq &= (1ull << 48) - 1; return seq; } EXPORT_SYMBOL(secure_dccp_sequence_number); #if IS_ENABLED(CONFIG_IPV6) u64 secure_dccpv6_sequence_number(__be32 *saddr, __be32 *daddr, __be16 sport, __be16 dport) { const struct { struct in6_addr saddr; struct in6_addr daddr; __be16 sport; __be16 dport; } __aligned(SIPHASH_ALIGNMENT) combined = { .saddr = *(struct in6_addr *)saddr, .daddr = *(struct in6_addr *)daddr, .sport = sport, .dport = dport }; u64 seq; net_secret_init(); seq = siphash(&combined, offsetofend(typeof(combined), dport), &net_secret); seq += ktime_get_real_ns(); seq &= (1ull << 48) - 1; return seq; } EXPORT_SYMBOL(secure_dccpv6_sequence_number); #endif #endif s='ctrl'>mode:
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /net/ipv4/ah4.c
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/ipv4/ah4.c')