Commit Graph

2478 Commits

Author SHA1 Message Date
Mao Wenan 9060cb719e net: crypto set sk to NULL when af_alg_release.
KASAN has found use-after-free in sockfs_setattr.
The existed commit 6d8c50dcb0 ("socket: close race condition between sock_close()
and sockfs_setattr()") is to fix this simillar issue, but it seems to ignore
that crypto module forgets to set the sk to NULL after af_alg_release.

KASAN report details as below:
BUG: KASAN: use-after-free in sockfs_setattr+0x120/0x150
Write of size 4 at addr ffff88837b956128 by task syz-executor0/4186

CPU: 2 PID: 4186 Comm: syz-executor0 Not tainted xxx + #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.10.2-1ubuntu1 04/01/2014
Call Trace:
 dump_stack+0xca/0x13e
 print_address_description+0x79/0x330
 ? vprintk_func+0x5e/0xf0
 kasan_report+0x18a/0x2e0
 ? sockfs_setattr+0x120/0x150
 sockfs_setattr+0x120/0x150
 ? sock_register+0x2d0/0x2d0
 notify_change+0x90c/0xd40
 ? chown_common+0x2ef/0x510
 chown_common+0x2ef/0x510
 ? chmod_common+0x3b0/0x3b0
 ? __lock_is_held+0xbc/0x160
 ? __sb_start_write+0x13d/0x2b0
 ? __mnt_want_write+0x19a/0x250
 do_fchownat+0x15c/0x190
 ? __ia32_sys_chmod+0x80/0x80
 ? trace_hardirqs_on_thunk+0x1a/0x1c
 __x64_sys_fchownat+0xbf/0x160
 ? lockdep_hardirqs_on+0x39a/0x5e0
 do_syscall_64+0xc8/0x580
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462589
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89
f7 48 89 d6 48 89
ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3
48 c7 c1 bc ff ff
ff f7 d8 64 89 01 48
RSP: 002b:00007fb4b2c83c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000104
RAX: ffffffffffffffda RBX: 000000000072bfa0 RCX: 0000000000462589
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000007
RBP: 0000000000000005 R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb4b2c846bc
R13: 00000000004bc733 R14: 00000000006f5138 R15: 00000000ffffffff

Allocated by task 4185:
 kasan_kmalloc+0xa0/0xd0
 __kmalloc+0x14a/0x350
 sk_prot_alloc+0xf6/0x290
 sk_alloc+0x3d/0xc00
 af_alg_accept+0x9e/0x670
 hash_accept+0x4a3/0x650
 __sys_accept4+0x306/0x5c0
 __x64_sys_accept4+0x98/0x100
 do_syscall_64+0xc8/0x580
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4184:
 __kasan_slab_free+0x12e/0x180
 kfree+0xeb/0x2f0
 __sk_destruct+0x4e6/0x6a0
 sk_destruct+0x48/0x70
 __sk_free+0xa9/0x270
 sk_free+0x2a/0x30
 af_alg_release+0x5c/0x70
 __sock_release+0xd3/0x280
 sock_close+0x1a/0x20
 __fput+0x27f/0x7f0
 task_work_run+0x136/0x1b0
 exit_to_usermode_loop+0x1a7/0x1d0
 do_syscall_64+0x461/0x580
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Syzkaller reproducer:
r0 = perf_event_open(&(0x7f0000000000)={0x0, 0x70, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @perf_config_ext}, 0x0, 0x0,
0xffffffffffffffff, 0x0)
r1 = socket$alg(0x26, 0x5, 0x0)
getrusage(0x0, 0x0)
bind(r1, &(0x7f00000001c0)=@alg={0x26, 'hash\x00', 0x0, 0x0,
'sha256-ssse3\x00'}, 0x80)
r2 = accept(r1, 0x0, 0x0)
r3 = accept4$unix(r2, 0x0, 0x0, 0x0)
r4 = dup3(r3, r0, 0x0)
fchownat(r4, &(0x7f00000000c0)='\x00', 0x0, 0x0, 0x1000)

Fixes: 6d8c50dcb0 ("socket: close race condition between sock_close() and sockfs_setattr()")
Signed-off-by: Mao Wenan <maowenan@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-18 12:01:24 -08:00
Eric Biggers d45a90cb5d crypto: sm3 - fix undefined shift by >= width of value
sm3_compress() calls rol32() with shift >= 32, which causes undefined
behavior.  This is easily detected by enabling CONFIG_UBSAN.

Explicitly AND with 31 to make the behavior well defined.

Fixes: 4f0fc1600e ("crypto: sm3 - add OSCCA SM3 secure hash")
Cc: <stable@vger.kernel.org> # v4.15+
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-10 21:37:32 +08:00
Eric Biggers 6db4341017 crypto: adiantum - initialize crypto_spawn::inst
crypto_grab_*() doesn't set crypto_spawn::inst, so templates must set it
beforehand.  Otherwise it will be left NULL, which causes a crash in
certain cases where algorithms are dynamically loaded/unloaded.  E.g.
with CONFIG_CRYPTO_CHACHA20_X86_64=m, the following caused a crash:

    insmod chacha-x86_64.ko
    python -c 'import socket; socket.socket(socket.AF_ALG, 5, 0).bind(("skcipher", "adiantum(xchacha12,aes)"))'
    rmmod chacha-x86_64.ko
    python -c 'import socket; socket.socket(socket.AF_ALG, 5, 0).bind(("skcipher", "adiantum(xchacha12,aes)"))'

Fixes: 059c2a4d8e ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-10 21:37:31 +08:00
Harsh Jain a777336362 crypto: authencesn - Avoid twice completion call in decrypt path
Authencesn template in decrypt path unconditionally calls aead_request_complete
after ahash_verify which leads to following kernel panic in after decryption.

[  338.539800] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
[  338.548372] PGD 0 P4D 0
[  338.551157] Oops: 0000 [#1] SMP PTI
[  338.554919] CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Tainted: G        W I       4.19.7+ #13
[  338.564431] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0        07/29/10
[  338.572212] RIP: 0010:esp_input_done2+0x350/0x410 [esp4]
[  338.578030] Code: ff 0f b6 68 10 48 8b 83 c8 00 00 00 e9 8e fe ff ff 8b 04 25 04 00 00 00 83 e8 01 48 98 48 8b 3c c5 10 00 00 00 e9 f7 fd ff ff <8b> 04 25 04 00 00 00 83 e8 01 48 98 4c 8b 24 c5 10 00 00 00 e9 3b
[  338.598547] RSP: 0018:ffff911c97803c00 EFLAGS: 00010246
[  338.604268] RAX: 0000000000000002 RBX: ffff911c4469ee00 RCX: 0000000000000000
[  338.612090] RDX: 0000000000000000 RSI: 0000000000000130 RDI: ffff911b87c20400
[  338.619874] RBP: 0000000000000000 R08: ffff911b87c20498 R09: 000000000000000a
[  338.627610] R10: 0000000000000001 R11: 0000000000000004 R12: 0000000000000000
[  338.635402] R13: ffff911c89590000 R14: ffff911c91730000 R15: 0000000000000000
[  338.643234] FS:  0000000000000000(0000) GS:ffff911c97800000(0000) knlGS:0000000000000000
[  338.652047] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  338.658299] CR2: 0000000000000004 CR3: 00000001ec20a000 CR4: 00000000000006f0
[  338.666382] Call Trace:
[  338.669051]  <IRQ>
[  338.671254]  esp_input_done+0x12/0x20 [esp4]
[  338.675922]  chcr_handle_resp+0x3b5/0x790 [chcr]
[  338.680949]  cpl_fw6_pld_handler+0x37/0x60 [chcr]
[  338.686080]  chcr_uld_rx_handler+0x22/0x50 [chcr]
[  338.691233]  uldrx_handler+0x8c/0xc0 [cxgb4]
[  338.695923]  process_responses+0x2f0/0x5d0 [cxgb4]
[  338.701177]  ? bitmap_find_next_zero_area_off+0x3a/0x90
[  338.706882]  ? matrix_alloc_area.constprop.7+0x60/0x90
[  338.712517]  ? apic_update_irq_cfg+0x82/0xf0
[  338.717177]  napi_rx_handler+0x14/0xe0 [cxgb4]
[  338.722015]  net_rx_action+0x2aa/0x3e0
[  338.726136]  __do_softirq+0xcb/0x280
[  338.730054]  irq_exit+0xde/0xf0
[  338.733504]  do_IRQ+0x54/0xd0
[  338.736745]  common_interrupt+0xf/0xf

Fixes: 104880a6b4 ("crypto: authencesn - Convert to new AEAD...")
Signed-off-by: Harsh Jain <harsh@chelsio.com>
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-10 21:37:31 +08:00
Eric Biggers 8f9c469348 crypto: authenc - fix parsing key with misaligned rta_len
Keys for "authenc" AEADs are formatted as an rtattr containing a 4-byte
'enckeylen', followed by an authentication key and an encryption key.
crypto_authenc_extractkeys() parses the key to find the inner keys.

However, it fails to consider the case where the rtattr's payload is
longer than 4 bytes but not 4-byte aligned, and where the key ends
before the next 4-byte aligned boundary.  In this case, 'keylen -=
RTA_ALIGN(rta->rta_len);' underflows to a value near UINT_MAX.  This
causes a buffer overread and crash during crypto_ahash_setkey().

Fix it by restricting the rtattr payload to the expected size.

Reproducer using AF_ALG:

	#include <linux/if_alg.h>
	#include <linux/rtnetlink.h>
	#include <sys/socket.h>

	int main()
	{
		int fd;
		struct sockaddr_alg addr = {
			.salg_type = "aead",
			.salg_name = "authenc(hmac(sha256),cbc(aes))",
		};
		struct {
			struct rtattr attr;
			__be32 enckeylen;
			char keys[1];
		} __attribute__((packed)) key = {
			.attr.rta_len = sizeof(key),
			.attr.rta_type = 1 /* CRYPTO_AUTHENC_KEYA_PARAM */,
		};

		fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
		bind(fd, (void *)&addr, sizeof(addr));
		setsockopt(fd, SOL_ALG, ALG_SET_KEY, &key, sizeof(key));
	}

It caused:

	BUG: unable to handle kernel paging request at ffff88007ffdc000
	PGD 2e01067 P4D 2e01067 PUD 2e04067 PMD 2e05067 PTE 0
	Oops: 0000 [#1] SMP
	CPU: 0 PID: 883 Comm: authenc Not tainted 4.20.0-rc1-00108-g00c9fe37a7f27 #13
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014
	RIP: 0010:sha256_ni_transform+0xb3/0x330 arch/x86/crypto/sha256_ni_asm.S:155
	[...]
	Call Trace:
	 sha256_ni_finup+0x10/0x20 arch/x86/crypto/sha256_ssse3_glue.c:321
	 crypto_shash_finup+0x1a/0x30 crypto/shash.c:178
	 shash_digest_unaligned+0x45/0x60 crypto/shash.c:186
	 crypto_shash_digest+0x24/0x40 crypto/shash.c:202
	 hmac_setkey+0x135/0x1e0 crypto/hmac.c:66
	 crypto_shash_setkey+0x2b/0xb0 crypto/shash.c:66
	 shash_async_setkey+0x10/0x20 crypto/shash.c:223
	 crypto_ahash_setkey+0x2d/0xa0 crypto/ahash.c:202
	 crypto_authenc_setkey+0x68/0x100 crypto/authenc.c:96
	 crypto_aead_setkey+0x2a/0xc0 crypto/aead.c:62
	 aead_setkey+0xc/0x10 crypto/algif_aead.c:526
	 alg_setkey crypto/af_alg.c:223 [inline]
	 alg_setsockopt+0xfe/0x130 crypto/af_alg.c:256
	 __sys_setsockopt+0x6d/0xd0 net/socket.c:1902
	 __do_sys_setsockopt net/socket.c:1913 [inline]
	 __se_sys_setsockopt net/socket.c:1910 [inline]
	 __x64_sys_setsockopt+0x1f/0x30 net/socket.c:1910
	 do_syscall_64+0x4a/0x180 arch/x86/entry/common.c:290
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: e236d4a89a ("[CRYPTO] authenc: Move enckeylen into key itself")
Cc: <stable@vger.kernel.org> # v2.6.25+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-10 21:37:31 +08:00
Linus Torvalds 769e47094d Kconfig updates for v4.21
- support -y option for merge_config.sh to avoid downgrading =y to =m
 
  - remove S_OTHER symbol type, and touch include/config/*.h files correctly
 
  - fix file name and line number in lexer warnings
 
  - fix memory leak when EOF is encountered in quotation
 
  - resolve all shift/reduce conflicts of the parser
 
  - warn no new line at end of file
 
  - make 'source' statement more strict to take only string literal
 
  - rewrite the lexer and remove the keyword lookup table
 
  - convert to SPDX License Identifier
 
  - compile C files independently instead of including them from zconf.y
 
  - fix various warnings of gconfig
 
  - misc cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcJieuAAoJED2LAQed4NsGHlIP/1s0fQ86XD9dIMyHzAO0gh2f
 7rylfe2kEXJgIzJ0DyZdLu4iZtwbkEUqTQrRS1abriNGVemPkfBAnZdM5d92lOQX
 3iREa700AJ2xo7V7gYZ6AbhZoG3p0S9U9Q2qE5S+tFTe8c2Gy4xtjnODF+Vel85r
 S0P8tF5sE1/d00lm+yfMI/CJVfDjyNaMm+aVEnL0kZTPiRkaktjWgo6Fc2p4z1L5
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 rcESVsIFpgqHWmTsdBk6dZk0q8yFZNkMlkaP/aYukVZpUn/N6oAXgTFckYl8dmQL
 fQBkQi6DTfr9EBPVbj18BKm7xI3Y4DdQ2fzTfYkJ2XwNRGFA5r9N3sjd7ZTVGjxC
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 ETFzd4Xu2/lZcL7gQRH8WU3L2S5iedmDG6RnZgJMXI0/9V4qAA+nlsWaCgnl1TgA
 mpxYlLUMrd6AUJevE34FlnyFdk8IMn9iKRFsvF0f3doO5C7QzTVGqFdJu5a0CuWO
 4NBJvZjFT8/4amoWLfnDlfApWXzTfwLbKG+r6V2F30fLuXpYg5LxWhBoGRPYLZSq
 oi4xN1Mpx3TvXz6WcKVZ
 =r3Fl
 -----END PGP SIGNATURE-----

Merge tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - support -y option for merge_config.sh to avoid downgrading =y to =m

 - remove S_OTHER symbol type, and touch include/config/*.h files correctly

 - fix file name and line number in lexer warnings

 - fix memory leak when EOF is encountered in quotation

 - resolve all shift/reduce conflicts of the parser

 - warn no new line at end of file

 - make 'source' statement more strict to take only string literal

 - rewrite the lexer and remove the keyword lookup table

 - convert to SPDX License Identifier

 - compile C files independently instead of including them from zconf.y

 - fix various warnings of gconfig

 - misc cleanups

* tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
  kconfig: surround dbg_sym_flags with #ifdef DEBUG to fix gconf warning
  kconfig: split images.c out of qconf.cc/gconf.c to fix gconf warnings
  kconfig: add static qualifiers to fix gconf warnings
  kconfig: split the lexer out of zconf.y
  kconfig: split some C files out of zconf.y
  kconfig: convert to SPDX License Identifier
  kconfig: remove keyword lookup table entirely
  kconfig: update current_pos in the second lexer
  kconfig: switch to ASSIGN_VAL state in the second lexer
  kconfig: stop associating kconf_id with yylval
  kconfig: refactor end token rules
  kconfig: stop supporting '.' and '/' in unquoted words
  treewide: surround Kconfig file paths with double quotes
  microblaze: surround string default in Kconfig with double quotes
  kconfig: use T_WORD instead of T_VARIABLE for variables
  kconfig: use specific tokens instead of T_ASSIGN for assignments
  kconfig: refactor scanning and parsing "option" properties
  kconfig: use distinct tokens for type and default properties
  kconfig: remove redundant token defines
  kconfig: rename depends_list to comment_option_list
  ...
2018-12-29 13:03:29 -08:00
Linus Torvalds b71acb0e37 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Add 1472-byte test to tcrypt for IPsec
   - Reintroduced crypto stats interface with numerous changes
   - Support incremental algorithm dumps

  Algorithms:
   - Add xchacha12/20
   - Add nhpoly1305
   - Add adiantum
   - Add streebog hash
   - Mark cts(cbc(aes)) as FIPS allowed

  Drivers:
   - Improve performance of arm64/chacha20
   - Improve performance of x86/chacha20
   - Add NEON-accelerated nhpoly1305
   - Add SSE2 accelerated nhpoly1305
   - Add AVX2 accelerated nhpoly1305
   - Add support for 192/256-bit keys in gcmaes AVX
   - Add SG support in gcmaes AVX
   - ESN for inline IPsec tx in chcr
   - Add support for CryptoCell 703 in ccree
   - Add support for CryptoCell 713 in ccree
   - Add SM4 support in ccree
   - Add SM3 support in ccree
   - Add support for chacha20 in caam/qi2
   - Add support for chacha20 + poly1305 in caam/jr
   - Add support for chacha20 + poly1305 in caam/qi2
   - Add AEAD cipher support in cavium/nitrox"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (130 commits)
  crypto: skcipher - remove remnants of internal IV generators
  crypto: cavium/nitrox - Fix build with !CONFIG_DEBUG_FS
  crypto: salsa20-generic - don't unnecessarily use atomic walk
  crypto: skcipher - add might_sleep() to skcipher_walk_virt()
  crypto: x86/chacha - avoid sleeping under kernel_fpu_begin()
  crypto: cavium/nitrox - Added AEAD cipher support
  crypto: mxc-scc - fix build warnings on ARM64
  crypto: api - document missing stats member
  crypto: user - remove unused dump functions
  crypto: chelsio - Fix wrong error counter increments
  crypto: chelsio - Reset counters on cxgb4 Detach
  crypto: chelsio - Handle PCI shutdown event
  crypto: chelsio - cleanup:send addr as value in function argument
  crypto: chelsio - Use same value for both channel in single WR
  crypto: chelsio - Swap location of AAD and IV sent in WR
  crypto: chelsio - remove set but not used variable 'kctx_len'
  crypto: ux500 - Use proper enum in hash_set_dma_transfer
  crypto: ux500 - Use proper enum in cryp_set_dma_transfer
  crypto: aesni - Add scatter/gather avx stubs, and use them in C
  crypto: aesni - Introduce partial block macro
  ..
2018-12-27 13:53:32 -08:00
Linus Torvalds 792bf4d871 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The biggest RCU changes in this cycle were:

   - Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

   - Replace calls of RCU-bh and RCU-sched update-side functions to
     their vanilla RCU counterparts. This series is a step towards
     complete removal of the RCU-bh and RCU-sched update-side functions.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - Documentation updates, including a number of flavor-consolidation
     updates from Joel Fernandes.

   - Miscellaneous fixes.

   - Automate generation of the initrd filesystem used for rcutorture
     testing.

   - Convert spin_is_locked() assertions to instead use lockdep.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - SRCU updates, especially including a fix from Dennis Krein for a
     bag-on-head-class bug.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
  rcutorture: Don't do busted forward-progress testing
  rcutorture: Use 100ms buckets for forward-progress callback histograms
  rcutorture: Recover from OOM during forward-progress tests
  rcutorture: Print forward-progress test age upon failure
  rcutorture: Print time since GP end upon forward-progress failure
  rcutorture: Print histogram of CB invocation at OOM time
  rcutorture: Print GP age upon forward-progress failure
  rcu: Print per-CPU callback counts for forward-progress failures
  rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings
  rcutorture: Dump grace-period diagnostics upon forward-progress OOM
  rcutorture: Prepare for asynchronous access to rcu_fwd_startat
  torture: Remove unnecessary "ret" variables
  rcutorture: Affinity forward-progress test to avoid housekeeping CPUs
  rcutorture: Break up too-long rcu_torture_fwd_prog() function
  rcutorture: Remove cbflood facility
  torture: Bring any extra CPUs online during kernel startup
  rcutorture: Add call_rcu() flooding forward-progress tests
  rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
  tools/kernel.h: Replace synchronize_sched() with synchronize_rcu()
  net/decnet: Replace rcu_barrier_bh() with rcu_barrier()
  ...
2018-12-26 13:07:19 -08:00
Eric Biggers c79b411eaa crypto: skcipher - remove remnants of internal IV generators
Remove dead code related to internal IV generators, which are no longer
used since they've been replaced with the "seqiv" and "echainiv"
templates.  The removed code includes:

- The "givcipher" (GIVCIPHER) algorithm type.  No algorithms are
  registered with this type anymore, so it's unneeded.

- The "const char *geniv" member of aead_alg, ablkcipher_alg, and
  blkcipher_alg.  A few algorithms still set this, but it isn't used
  anymore except to show via /proc/crypto and CRYPTO_MSG_GETALG.
  Just hardcode "<default>" or "<none>" in those cases.

- The 'skcipher_givcrypt_request' structure, which is never used.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23 11:52:45 +08:00
Eric Biggers 101b53d91d crypto: salsa20-generic - don't unnecessarily use atomic walk
salsa20-generic doesn't use SIMD instructions or otherwise disable
preemption, so passing atomic=true to skcipher_walk_virt() is
unnecessary.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23 11:52:44 +08:00
Eric Biggers bb648291fc crypto: skcipher - add might_sleep() to skcipher_walk_virt()
skcipher_walk_virt() can still sleep even with atomic=true, since that
only affects the later calls to skcipher_walk_done().  But,
skcipher_walk_virt() only has to allocate memory for some input data
layouts, so incorrectly calling it with preemption disabled can go
undetected.  Use might_sleep() so that it's detected reliably.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23 11:52:44 +08:00
Corentin Labbe 0c99c2a087 crypto: user - remove unused dump functions
This patch removes unused dump functions for crypto_user_stats.
There are remains of the copy/paste of crypto_user_base to
crypto_user_stat and I forgot to remove them.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23 11:52:44 +08:00
Masahiro Yamada 8636a1f967 treewide: surround Kconfig file paths with double quotes
The Kconfig lexer supports special characters such as '.' and '/' in
the parameter context. In my understanding, the reason is just to
support bare file paths in the source statement.

I do not see a good reason to complicate Kconfig for the room of
ambiguity.

The majority of code already surrounds file paths with double quotes,
and it makes sense since file paths are constant string literals.

Make it treewide consistent now.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
2018-12-22 00:25:54 +09:00
Eric Biggers 00c9fe37a7 crypto: adiantum - fix leaking reference to hash algorithm
crypto_alg_mod_lookup() takes a reference to the hash algorithm but
crypto_init_shash_spawn() doesn't take ownership of it, hence the
reference needs to be dropped in adiantum_create().

Fixes: 059c2a4d8e ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:59 +08:00
Eric Biggers 0ac6b8fb23 crypto: user - support incremental algorithm dumps
CRYPTO_MSG_GETALG in NLM_F_DUMP mode sometimes doesn't return all
registered crypto algorithms, because it doesn't support incremental
dumps.  crypto_dump_report() only permits itself to be called once, yet
the netlink subsystem allocates at most ~64 KiB for the skb being dumped
to.  Thus only the first recvmsg() returns data, and it may only include
a subset of the crypto algorithms even if the user buffer passed to
recvmsg() is large enough to hold all of them.

Fix this by using one of the arguments in the netlink_callback structure
to keep track of the current position in the algorithm list.  Then
userspace can do multiple recvmsg() on the socket after sending the dump
request.  This is the way netlink dumps work elsewhere in the kernel;
it's unclear why this was different (probably just an oversight).

Also fix an integer overflow when calculating the dump buffer size hint.

Fixes: a38f7907b9 ("crypto: Add userspace configuration API")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:59 +08:00
Eric Biggers c6018e1a00 crypto: adiantum - adjust some comments to match latest paper
The 2018-11-28 revision of the Adiantum paper has revised some notation:

- 'M' was replaced with 'L' (meaning "Left", for the left-hand part of
  the message) in the definition of Adiantum hashing, to avoid confusion
  with the full message
- ε-almost-∆-universal is now abbreviated as ε-∆U instead of εA∆U
- "block" is now used only to mean block cipher and Poly1305 blocks

Also, Adiantum hashing was moved from the appendix to the main paper.

To avoid confusion, update relevant comments in the code to match.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:59 +08:00
Eric Biggers 282c14852d crypto: xchacha20 - fix comments for test vectors
The kernel's ChaCha20 uses the RFC7539 convention of the nonce being 12
bytes rather than 8, so actually I only appended 12 random bytes (not
16) to its test vectors to form 24-byte nonces for the XChaCha20 test
vectors.  The other 4 bytes were just from zero-padding the stream
position to 8 bytes.  Fix the comments above the test vectors.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:59 +08:00
Eric Biggers 5569e8c074 crypto: xchacha - add test vector from XChaCha20 draft RFC
There is a draft specification for XChaCha20 being worked on.  Add the
XChaCha20 test vector from the appendix so that we can be extra sure the
kernel's implementation is compatible.

I also recomputed the ciphertext with XChaCha12 and added it there too,
to keep the tests for XChaCha20 and XChaCha12 in sync.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:58 +08:00
Eric Biggers 7a507d6225 crypto: x86/chacha - add XChaCha12 support
Now that the x86_64 SIMD implementations of ChaCha20 and XChaCha20 have
been refactored to support varying the number of rounds, add support for
XChaCha12.  This is identical to XChaCha20 except for the number of
rounds, which is 12 instead of 20.  This can be used by Adiantum.

Reviewed-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:58 +08:00
Eric Biggers 4af7826187 crypto: x86/chacha20 - add XChaCha20 support
Add an XChaCha20 implementation that is hooked up to the x86_64 SIMD
implementations of ChaCha20.  This can be used by Adiantum.

An SSSE3 implementation of single-block HChaCha20 is also added so that
XChaCha20 can use it rather than the generic implementation.  This
required refactoring the ChaCha permutation into its own function.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:57 +08:00
Eric Biggers 0f961f9f67 crypto: x86/nhpoly1305 - add AVX2 accelerated NHPoly1305
Add a 64-bit AVX2 implementation of NHPoly1305, an ε-almost-∆-universal
hash function used in the Adiantum encryption mode.  For now, only the
NH portion is actually AVX2-accelerated; the Poly1305 part is less
performance-critical so is just implemented in C.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:57 +08:00
Eric Biggers 012c82388c crypto: x86/nhpoly1305 - add SSE2 accelerated NHPoly1305
Add a 64-bit SSE2 implementation of NHPoly1305, an ε-almost-∆-universal
hash function used in the Adiantum encryption mode.  For now, only the
NH portion is actually SSE2-accelerated; the Poly1305 part is less
performance-critical so is just implemented in C.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:57 +08:00
Eric Biggers b299362ee4 crypto: adiantum - propagate CRYPTO_ALG_ASYNC flag to instance
If the stream cipher implementation is asynchronous, then the Adiantum
instance must be flagged as asynchronous as well.  Otherwise someone
asking for a synchronous algorithm can get an asynchronous algorithm.

There are no asynchronous xchacha12 or xchacha20 implementations yet
which makes this largely a theoretical issue, but it should be fixed.

Fixes: 059c2a4d8e ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:56 +08:00
Ard Biesheuvel ee5bbc9fd3 crypto: tcrypt - add block size of 1472 to skcipher template
In order to have better coverage of algorithms operating on block
sizes that are in the ballpark of a VPN  packet, add 1472 to the
block_sizes array.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-13 18:24:40 +08:00
Corentin Labbe 1f6669b971 crypto: user - Add crypto_stats_init
This patch add the crypto_stats_init() function.
This will permit to remove some ifdef from __crypto_register_alg().

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 44f13133cb crypto: user - rename err_cnt parameter
Since now all crypto stats are on their own structures, it is now
useless to have the algorithm name in the err_cnt member.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 17c18f9e33 crypto: user - Split stats in multiple structures
Like for userspace, this patch splits stats into multiple structures,
one for each algorithm class.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 5fff81729f crypto: user - remove intermediate variable
The use of the v64 intermediate variable is useless, and removing it
bring to much readable code.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe b0af91c141 crypto: user - Fix invalid stat reporting
Some error count use the wrong name for getting this data.
But this had not caused any reporting problem, since all error count are shared in the same
union.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe f7d76e05d0 crypto: user - fix use_after_free of struct xxx_request
All crypto_stats functions use the struct xxx_request for feeding stats,
but in some case this structure could already be freed.

For fixing this, the needed parameters (len and alg) will be stored
before the request being executed.
Fixes: cac5818c25 ("crypto: user - Implement a generic crypto statistics")
Reported-by: syzbot <syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com>

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 7f0a9d5c9d crypto: user - split user space crypto stat structures
It is cleaner to have each stat in their own structures.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 6e8e72cd20 crypto: user - convert all stats from u32 to u64
All the 32-bit fields need to be 64-bit.  In some cases, UINT32_MAX crypto
operations can be done in seconds.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe a6a3138536 crypto: user - CRYPTO_STATS should depend on CRYPTO_USER
CRYPTO_STATS is using CRYPTO_USER stuff, so it should depends on it.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Corentin Labbe 2ced26078f crypto: user - made crypto_user_stat optional
Even if CRYPTO_STATS is set to n, some part of CRYPTO_STATS are
compiled.
This patch made all part of crypto_user_stat uncompiled in that case.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Herbert Xu 946dca8fe4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Merge crypto tree to pick up crypto stats API revert.
2018-12-07 13:59:10 +08:00
Herbert Xu e61efff4ae crypto: user - Disable statistics interface
Since this user-space API is still undergoing significant changes,
this patch disables it for the current merge window.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 13:56:08 +08:00
Ingo Molnar 4bbfd7467c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

- Replace calls of RCU-bh and RCU-sched update-side functions
  to their vanilla RCU counterparts.  This series is a step
  towards complete removal of the RCU-bh and RCU-sched update-side
  functions.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- Documentation updates, including a number of flavor-consolidation
  updates from Joel Fernandes.

- Miscellaneous fixes.

- Automate generation of the initrd filesystem used for
  rcutorture testing.

- Convert spin_is_locked() assertions to instead use lockdep.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- SRCU updates, especially including a fix from Dennis Krein
  for a bag-on-head-class bug.

- RCU torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-04 07:52:30 +01:00
Pan Bian e5bde04ccc crypto: do not free algorithm before using
In multiple functions, the algorithm fields are read after its reference
is dropped through crypto_mod_put. In this case, the algorithm memory
may be freed, resulting in use-after-free bugs. This patch delays the
put operation until the algorithm is never used.

Fixes: 79c65d179a ("crypto: cbc - Convert to skcipher")
Fixes: a7d85e06ed ("crypto: cfb - add support for Cipher FeedBack mode")
Fixes: 043a44001b ("crypto: pcbc - Convert to skcipher")
Cc: <stable@vger.kernel.org>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-29 14:53:59 +08:00
Paul E. McKenney a0076e1778 crypto/pcrypt: Replace synchronize_rcu_bh() with synchronize_rcu()
Now that synchronize_rcu() waits for bh-disable regions of code as
well as RCU read-side critical sections, the synchronize_rcu_bh() in
pcrypt_cpumask_change_notify() can be replaced by synchronize_rcu().
This commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: <linux-crypto@vger.kernel.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-27 09:18:59 -08:00
Eric Biggers 059c2a4d8e crypto: adiantum - add Adiantum support
Add support for the Adiantum encryption mode.  Adiantum was designed by
Paul Crowley and is specified by our paper:

    Adiantum: length-preserving encryption for entry-level processors
    (https://eprint.iacr.org/2018/720.pdf)

See our paper for full details; this patch only provides an overview.

Adiantum is a tweakable, length-preserving encryption mode designed for
fast and secure disk encryption, especially on CPUs without dedicated
crypto instructions.  Adiantum encrypts each sector using the XChaCha12
stream cipher, two passes of an ε-almost-∆-universal (εA∆U) hash
function, and an invocation of the AES-256 block cipher on a single
16-byte block.  On CPUs without AES instructions, Adiantum is much
faster than AES-XTS; for example, on ARM Cortex-A7, on 4096-byte sectors
Adiantum encryption is about 4 times faster than AES-256-XTS encryption,
and decryption about 5 times faster.

Adiantum is a specialization of the more general HBSH construction.  Our
earlier proposal, HPolyC, was also a HBSH specialization, but it used a
different εA∆U hash function, one based on Poly1305 only.  Adiantum's
εA∆U hash function, which is based primarily on the "NH" hash function
like that used in UMAC (RFC4418), is about twice as fast as HPolyC's;
consequently, Adiantum is about 20% faster than HPolyC.

This speed comes with no loss of security: Adiantum is provably just as
secure as HPolyC, in fact slightly *more* secure.  Like HPolyC,
Adiantum's security is reducible to that of XChaCha12 and AES-256,
subject to a security bound.  XChaCha12 itself has a security reduction
to ChaCha12.  Therefore, one need not "trust" Adiantum; one need only
trust ChaCha12 and AES-256.  Note that the εA∆U hash function is only
used for its proven combinatorical properties so cannot be "broken".

Adiantum is also a true wide-block encryption mode, so flipping any
plaintext bit in the sector scrambles the entire ciphertext, and vice
versa.  No other such mode is available in the kernel currently; doing
the same with XTS scrambles only 16 bytes.  Adiantum also supports
arbitrary-length tweaks and naturally supports any length input >= 16
bytes without needing "ciphertext stealing".

For the stream cipher, Adiantum uses XChaCha12 rather than XChaCha20 in
order to make encryption feasible on the widest range of devices.
Although the 20-round variant is quite popular, the best known attacks
on ChaCha are on only 7 rounds, so ChaCha12 still has a substantial
security margin; in fact, larger than AES-256's.  12-round Salsa20 is
also the eSTREAM recommendation.  For the block cipher, Adiantum uses
AES-256, despite it having a lower security margin than XChaCha12 and
needing table lookups, due to AES's extensive adoption and analysis
making it the obvious first choice.  Nevertheless, for flexibility this
patch also permits the "adiantum" template to be instantiated with
XChaCha20 and/or with an alternate block cipher.

We need Adiantum support in the kernel for use in dm-crypt and fscrypt,
where currently the only other suitable options are block cipher modes
such as AES-XTS.  A big problem with this is that many low-end mobile
devices (e.g. Android Go phones sold primarily in developing countries,
as well as some smartwatches) still have CPUs that lack AES
instructions, e.g. ARM Cortex-A7.  Sadly, AES-XTS encryption is much too
slow to be viable on these devices.  We did find that some "lightweight"
block ciphers are fast enough, but these suffer from problems such as
not having much cryptanalysis or being too controversial.

The ChaCha stream cipher has excellent performance but is insecure to
use directly for disk encryption, since each sector's IV is reused each
time it is overwritten.  Even restricting the threat model to offline
attacks only isn't enough, since modern flash storage devices don't
guarantee that "overwrites" are really overwrites, due to wear-leveling.
Adiantum avoids this problem by constructing a
"tweakable super-pseudorandom permutation"; this is the strongest
possible security model for length-preserving encryption.

Of course, storing random nonces along with the ciphertext would be the
ideal solution.  But doing that with existing hardware and filesystems
runs into major practical problems; in most cases it would require data
journaling (like dm-integrity) which severely degrades performance.
Thus, for now length-preserving encryption is still needed.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:56 +08:00
Eric Biggers 26609a21a9 crypto: nhpoly1305 - add NHPoly1305 support
Add a generic implementation of NHPoly1305, an ε-almost-∆-universal hash
function used in the Adiantum encryption mode.

CONFIG_NHPOLY1305 is not selectable by itself since there won't be any
real reason to enable it without also enabling Adiantum support.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:56 +08:00
Eric Biggers 1b6fd3d5d1 crypto: poly1305 - add Poly1305 core API
Expose a low-level Poly1305 API which implements the
ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305 MAC
and supports block-aligned inputs only.

This is needed for Adiantum hashing, which builds an εA∆U hash function
from NH and a polynomial evaluation in GF(2^{130}-5); this polynomial
evaluation is identical to the one the Poly1305 MAC does.  However, the
crypto_shash Poly1305 API isn't very appropriate for this because its
calling convention assumes it is used as a MAC, with a 32-byte "one-time
key" provided for every digest.

But by design, in Adiantum hashing the performance of the polynomial
evaluation isn't nearly as critical as NH.  So it suffices to just have
some C helper functions.  Thus, this patch adds such functions.

Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:56 +08:00
Eric Biggers 878afc35cd crypto: poly1305 - use structures for key and accumulator
In preparation for exposing a low-level Poly1305 API which implements
the ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305
MAC and supports block-aligned inputs only, create structures
poly1305_key and poly1305_state which hold the limbs of the Poly1305
"r" key and accumulator, respectively.

These structures could actually have the same type (e.g. poly1305_val),
but different types are preferable, to prevent misuse.

Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:56 +08:00
Eric Biggers aa7624093c crypto: chacha - add XChaCha12 support
Now that the generic implementation of ChaCha20 has been refactored to
allow varying the number of rounds, add support for XChaCha12, which is
the XSalsa construction applied to ChaCha12.  ChaCha12 is one of the
three ciphers specified by the original ChaCha paper
(https://cr.yp.to/chacha/chacha-20080128.pdf: "ChaCha, a variant of
Salsa20"), alongside ChaCha8 and ChaCha20.  ChaCha12 is faster than
ChaCha20 but has a lower, but still large, security margin.

We need XChaCha12 support so that it can be used in the Adiantum
encryption mode, which enables disk/file encryption on low-end mobile
devices where AES-XTS is too slow as the CPUs lack AES instructions.

We'd prefer XChaCha20 (the more popular variant), but it's too slow on
some of our target devices, so at least in some cases we do need the
XChaCha12-based version.  In more detail, the problem is that Adiantum
is still much slower than we're happy with, and encryption still has a
quite noticeable effect on the feel of low-end devices.  Users and
vendors push back hard against encryption that degrades the user
experience, which always risks encryption being disabled entirely.  So
we need to choose the fastest option that gives us a solid margin of
security, and here that's XChaCha12.  The best known attack on ChaCha
breaks only 7 rounds and has 2^235 time complexity, so ChaCha12's
security margin is still better than AES-256's.  Much has been learned
about cryptanalysis of ARX ciphers since Salsa20 was originally designed
in 2005, and it now seems we can be comfortable with a smaller number of
rounds.  The eSTREAM project also suggests the 12-round version of
Salsa20 as providing the best balance among the different variants:
combining very good performance with a "comfortable margin of security".

Note that it would be trivial to add vanilla ChaCha12 in addition to
XChaCha12.  However, it's unneeded for now and therefore is omitted.

As discussed in the patch that introduced XChaCha20 support, I
considered splitting the code into separate chacha-common, chacha20,
xchacha20, and xchacha12 modules, so that these algorithms could be
enabled/disabled independently.  However, since nearly all the code is
shared anyway, I ultimately decided there would have been little benefit
to the added complexity.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Eric Biggers 1ca1b91794 crypto: chacha20-generic - refactor to allow varying number of rounds
In preparation for adding XChaCha12 support, rename/refactor
chacha20-generic to support different numbers of rounds.  The
justification for needing XChaCha12 support is explained in more detail
in the patch "crypto: chacha - add XChaCha12 support".

The only difference between ChaCha{8,12,20} are the number of rounds
itself; all other parts of the algorithm are the same.  Therefore,
remove the "20" from all definitions, structures, functions, files, etc.
that will be shared by all ChaCha versions.

Also make ->setkey() store the round count in the chacha_ctx (previously
chacha20_ctx).  The generic code then passes the round count through to
chacha_block().  There will be a ->setkey() function for each explicitly
allowed round count; the encrypt/decrypt functions will be the same.  I
decided not to do it the opposite way (same ->setkey() function for all
round counts, with different encrypt/decrypt functions) because that
would have required more boilerplate code in architecture-specific
implementations of ChaCha and XChaCha.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Eric Biggers de61d7ae5d crypto: chacha20-generic - add XChaCha20 support
Add support for the XChaCha20 stream cipher.  XChaCha20 is the
application of the XSalsa20 construction
(https://cr.yp.to/snuffle/xsalsa-20081128.pdf) to ChaCha20 rather than
to Salsa20.  XChaCha20 extends ChaCha20's nonce length from 64 bits (or
96 bits, depending on convention) to 192 bits, while provably retaining
ChaCha20's security.  XChaCha20 uses the ChaCha20 permutation to map the
key and first 128 nonce bits to a 256-bit subkey.  Then, it does the
ChaCha20 stream cipher with the subkey and remaining 64 bits of nonce.

We need XChaCha support in order to add support for the Adiantum
encryption mode.  Note that to meet our performance requirements, we
actually plan to primarily use the variant XChaCha12.  But we believe
it's wise to first add XChaCha20 as a baseline with a higher security
margin, in case there are any situations where it can be used.
Supporting both variants is straightforward.

Since XChaCha20's subkey differs for each request, XChaCha20 can't be a
template that wraps ChaCha20; that would require re-keying the
underlying ChaCha20 for every request, which wouldn't be thread-safe.
Instead, we make XChaCha20 its own top-level algorithm which calls the
ChaCha20 streaming implementation internally.

Similar to the existing ChaCha20 implementation, we define the IV to be
the nonce and stream position concatenated together.  This allows users
to seek to any position in the stream.

I considered splitting the code into separate chacha20-common, chacha20,
and xchacha20 modules, so that chacha20 and xchacha20 could be
enabled/disabled independently.  However, since nearly all the code is
shared anyway, I ultimately decided there would have been little benefit
to the added complexity of separate modules.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Eric Biggers 5e04542a0e crypto: chacha20-generic - don't unnecessarily use atomic walk
chacha20-generic doesn't use SIMD instructions or otherwise disable
preemption, so passing atomic=true to skcipher_walk_virt() is
unnecessary.

Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Eric Biggers d41655909e crypto: remove useless initializations of cra_list
Some algorithms initialize their .cra_list prior to registration.
But this is unnecessary since crypto_register_alg() will overwrite
.cra_list when adding the algorithm to the 'crypto_alg_list'.
Apparently the useless assignment has just been copy+pasted around.

So, remove the useless assignments.

Exception: paes_s390.c uses cra_list to check whether the algorithm is
registered or not, so I left that as-is for now.

This patch shouldn't change any actual behavior.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Vitaly Chikunov 3da2c1dfdb crypto: ecc - regularize scalar for scalar multiplication
ecc_point_mult is supposed to be used with a regularized scalar,
otherwise, it's possible to deduce the position of the top bit of the
scalar with timing attack. This is important when the scalar is a
private key.

ecc_point_mult is already using a regular algorithm (i.e. having an
operation flow independent of the input scalar) but regularization step
is not implemented.

Arrange scalar to always have fixed top bit by adding a multiple of the
curve order (n).

References:
The constant time regularization step is based on micro-ecc by Kenneth
MacKay and also referenced in the literature (Bernstein, D. J., & Lange,
T. (2017). Montgomery curves and the Montgomery ladder. (Cryptology
ePrint Archive; Vol. 2017/293). s.l.: IACR. Chapter 4.6.2.)

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Cc: kernel-hardening@lists.openwall.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-16 14:11:04 +08:00
Cristian Stoica 193188e551 crypto: chacha20poly1305 - export CHACHAPOLY_IV_SIZE
Move CHACHAPOLY_IV_SIZE to header file, so it can be reused.

Signed-off-by: Cristian Stoica <cristian.stoica@nxp.com>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-16 14:11:03 +08:00