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crypto: aesni - Introduce partial block macro

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Before this diff, multiple calls to GCM_ENC_DEC will
succeed, but only if all calls are a multiple of 16 bytes.

Handle partial blocks at the start of GCM_ENC_DEC, and update
aadhash as appropriate.

The data offset %r11 is also updated after the partial block.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Dave Watson 2018-02-14 09:40:19 -08:00 committed by Herbert Xu
parent 1476db2d12
commit ae952c5ec6
1 changed files with 150 additions and 1 deletions
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151
arch/x86/crypto/aesni-intel_asm.S
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@ -285,7 +285,13 @@ ALL_F: .octa 0xffffffffffffffffffffffffffffffff
movdqu AadHash(%arg2), %xmm8
movdqu HashKey(%arg2), %xmm13
add %arg5, InLen(%arg2)
xor %r11, %r11 # initialise the data pointer offset as zero
PARTIAL_BLOCK %arg3 %arg4 %arg5 %r11 %xmm8 \operation
sub %r11, %arg5 # sub partial block data used
mov %arg5, %r13 # save the number of bytes
and $-16, %r13 # %r13 = %r13 - (%r13 mod 16)
mov %r13, %r12
# Encrypt/Decrypt first few blocks
@ -606,6 +612,150 @@ _get_AAD_done\@:
movdqu \TMP6, AadHash(%arg2)
.endm
# PARTIAL_BLOCK: Handles encryption/decryption and the tag partial blocks
# between update calls.
# Requires the input data be at least 1 byte long due to READ_PARTIAL_BLOCK
# Outputs encrypted bytes, and updates hash and partial info in gcm_data_context
# Clobbers rax, r10, r12, r13, xmm0-6, xmm9-13
.macro PARTIAL_BLOCK CYPH_PLAIN_OUT PLAIN_CYPH_IN PLAIN_CYPH_LEN DATA_OFFSET \
AAD_HASH operation
mov PBlockLen(%arg2), %r13
cmp $0, %r13
je _partial_block_done_\@ # Leave Macro if no partial blocks
# Read in input data without over reading
cmp $16, \PLAIN_CYPH_LEN
jl _fewer_than_16_bytes_\@
movups (\PLAIN_CYPH_IN), %xmm1 # If more than 16 bytes, just fill xmm
jmp _data_read_\@
_fewer_than_16_bytes_\@:
lea (\PLAIN_CYPH_IN, \DATA_OFFSET, 1), %r10
mov \PLAIN_CYPH_LEN, %r12
READ_PARTIAL_BLOCK %r10 %r12 %xmm0 %xmm1
mov PBlockLen(%arg2), %r13
_data_read_\@: # Finished reading in data
movdqu PBlockEncKey(%arg2), %xmm9
movdqu HashKey(%arg2), %xmm13
lea SHIFT_MASK(%rip), %r12
# adjust the shuffle mask pointer to be able to shift r13 bytes
# r16-r13 is the number of bytes in plaintext mod 16)
add %r13, %r12
movdqu (%r12), %xmm2 # get the appropriate shuffle mask
PSHUFB_XMM %xmm2, %xmm9 # shift right r13 bytes
.ifc \operation, dec
movdqa %xmm1, %xmm3
pxor %xmm1, %xmm9 # Cyphertext XOR E(K, Yn)
mov \PLAIN_CYPH_LEN, %r10
add %r13, %r10
# Set r10 to be the amount of data left in CYPH_PLAIN_IN after filling
sub $16, %r10
# Determine if if partial block is not being filled and
# shift mask accordingly
jge _no_extra_mask_1_\@
sub %r10, %r12
_no_extra_mask_1_\@:
movdqu ALL_F-SHIFT_MASK(%r12), %xmm1
# get the appropriate mask to mask out bottom r13 bytes of xmm9
pand %xmm1, %xmm9 # mask out bottom r13 bytes of xmm9
pand %xmm1, %xmm3
movdqa SHUF_MASK(%rip), %xmm10
PSHUFB_XMM %xmm10, %xmm3
PSHUFB_XMM %xmm2, %xmm3
pxor %xmm3, \AAD_HASH
cmp $0, %r10
jl _partial_incomplete_1_\@
# GHASH computation for the last <16 Byte block
GHASH_MUL \AAD_HASH, %xmm13, %xmm0, %xmm10, %xmm11, %xmm5, %xmm6
xor %rax,%rax
mov %rax, PBlockLen(%arg2)
jmp _dec_done_\@
_partial_incomplete_1_\@:
add \PLAIN_CYPH_LEN, PBlockLen(%arg2)
_dec_done_\@:
movdqu \AAD_HASH, AadHash(%arg2)
.else
pxor %xmm1, %xmm9 # Plaintext XOR E(K, Yn)
mov \PLAIN_CYPH_LEN, %r10
add %r13, %r10
# Set r10 to be the amount of data left in CYPH_PLAIN_IN after filling
sub $16, %r10
# Determine if if partial block is not being filled and
# shift mask accordingly
jge _no_extra_mask_2_\@
sub %r10, %r12
_no_extra_mask_2_\@:
movdqu ALL_F-SHIFT_MASK(%r12), %xmm1
# get the appropriate mask to mask out bottom r13 bytes of xmm9
pand %xmm1, %xmm9
movdqa SHUF_MASK(%rip), %xmm1
PSHUFB_XMM %xmm1, %xmm9
PSHUFB_XMM %xmm2, %xmm9
pxor %xmm9, \AAD_HASH
cmp $0, %r10
jl _partial_incomplete_2_\@
# GHASH computation for the last <16 Byte block
GHASH_MUL \AAD_HASH, %xmm13, %xmm0, %xmm10, %xmm11, %xmm5, %xmm6
xor %rax,%rax
mov %rax, PBlockLen(%arg2)
jmp _encode_done_\@
_partial_incomplete_2_\@:
add \PLAIN_CYPH_LEN, PBlockLen(%arg2)
_encode_done_\@:
movdqu \AAD_HASH, AadHash(%arg2)
movdqa SHUF_MASK(%rip), %xmm10
# shuffle xmm9 back to output as ciphertext
PSHUFB_XMM %xmm10, %xmm9
PSHUFB_XMM %xmm2, %xmm9
.endif
# output encrypted Bytes
cmp $0, %r10
jl _partial_fill_\@
mov %r13, %r12
mov $16, %r13
# Set r13 to be the number of bytes to write out
sub %r12, %r13
jmp _count_set_\@
_partial_fill_\@:
mov \PLAIN_CYPH_LEN, %r13
_count_set_\@:
movdqa %xmm9, %xmm0
MOVQ_R64_XMM %xmm0, %rax
cmp $8, %r13
jle _less_than_8_bytes_left_\@
mov %rax, (\CYPH_PLAIN_OUT, \DATA_OFFSET, 1)
add $8, \DATA_OFFSET
psrldq $8, %xmm0
MOVQ_R64_XMM %xmm0, %rax
sub $8, %r13
_less_than_8_bytes_left_\@:
movb %al, (\CYPH_PLAIN_OUT, \DATA_OFFSET, 1)
add $1, \DATA_OFFSET
shr $8, %rax
sub $1, %r13
jne _less_than_8_bytes_left_\@
_partial_block_done_\@:
.endm # PARTIAL_BLOCK
/*
* if a = number of total plaintext bytes
* b = floor(a/16)
@ -624,7 +774,6 @@ _get_AAD_done\@:
movdqu AadHash(%arg2), %xmm\i # XMM0 = Y0
xor %r11, %r11 # initialise the data pointer offset as zero
# start AES for num_initial_blocks blocks
movdqu CurCount(%arg2), \XMM0 # XMM0 = Y0