[PATCH 05/14] x86/crypto: aesni: Merge encode and decode to GCM_ENC_DEC macro

From: Dave Watson
Date: Mon Feb 12 2018 - 14:52:03 EST

Make a macro for the main encode/decode routine. Only a small handful
of lines differ for enc and dec. This will also become the main
scatter/gather update routine.

Signed-off-by: Dave Watson <davejwatson@xxxxxx>
---
arch/x86/crypto/aesni-intel_asm.S | 293 +++++++++++++++-----------------------
1 file changed, 114 insertions(+), 179 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index 529c542..8021fd1 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -222,6 +222,118 @@ ALL_F: .octa 0xffffffffffffffffffffffffffffffff
mov %r13, %r12
.endm

+# GCM_ENC_DEC Encodes/Decodes given data. Assumes that the passed gcm_context
+# struct has been initialized by GCM_INIT.
+# Requires the input data be at least 1 byte long because of READ_PARTIAL_BLOCK
+# Clobbers rax, r10-r13, and xmm0-xmm15
+.macro GCM_ENC_DEC operation
+ # Encrypt/Decrypt first few blocks
+
+ and $(3<<4), %r12
+ jz _initial_num_blocks_is_0_\@
+ cmp $(2<<4), %r12
+ jb _initial_num_blocks_is_1_\@
+ je _initial_num_blocks_is_2_\@
+_initial_num_blocks_is_3_\@:
+ INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
+%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 5, 678, \operation
+ sub $48, %r13
+ jmp _initial_blocks_\@
+_initial_num_blocks_is_2_\@:
+ INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
+%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 6, 78, \operation
+ sub $32, %r13
+ jmp _initial_blocks_\@
+_initial_num_blocks_is_1_\@:
+ INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
+%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 7, 8, \operation
+ sub $16, %r13
+ jmp _initial_blocks_\@
+_initial_num_blocks_is_0_\@:
+ INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
+%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 8, 0, \operation
+_initial_blocks_\@:
+
+ # Main loop - Encrypt/Decrypt remaining blocks
+
+ cmp $0, %r13
+ je _zero_cipher_left_\@
+ sub $64, %r13
+ je _four_cipher_left_\@
+_crypt_by_4_\@:
+ GHASH_4_ENCRYPT_4_PARALLEL_\operation %xmm9, %xmm10, %xmm11, %xmm12, \
+ %xmm13, %xmm14, %xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, \
+ %xmm7, %xmm8, enc
+ add $64, %r11
+ sub $64, %r13
+ jne _crypt_by_4_\@
+_four_cipher_left_\@:
+ GHASH_LAST_4 %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, \
+%xmm15, %xmm1, %xmm2, %xmm3, %xmm4, %xmm8
+_zero_cipher_left_\@:
+ mov %arg4, %r13
+ and $15, %r13 # %r13 = arg4 (mod 16)
+ je _multiple_of_16_bytes_\@
+
+ # Handle the last <16 Byte block separately
+ paddd ONE(%rip), %xmm0 # INCR CNT to get Yn
+ movdqa SHUF_MASK(%rip), %xmm10
+ PSHUFB_XMM %xmm10, %xmm0
+
+ ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # Encrypt(K, Yn)
+
+ lea (%arg3,%r11,1), %r10
+ mov %r13, %r12
+ READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1
+
+ lea ALL_F+16(%rip), %r12
+ sub %r13, %r12
+.ifc \operation, dec
+ movdqa %xmm1, %xmm2
+.endif
+ pxor %xmm1, %xmm0 # XOR Encrypt(K, Yn)
+ movdqu (%r12), %xmm1
+ # get the appropriate mask to mask out top 16-r13 bytes of xmm0
+ pand %xmm1, %xmm0 # mask out top 16-r13 bytes of xmm0
+.ifc \operation, dec
+ pand %xmm1, %xmm2
+ movdqa SHUF_MASK(%rip), %xmm10
+ PSHUFB_XMM %xmm10 ,%xmm2
+
+ pxor %xmm2, %xmm8
+.else
+ movdqa SHUF_MASK(%rip), %xmm10
+ PSHUFB_XMM %xmm10,%xmm0
+
+ pxor %xmm0, %xmm8
+.endif
+
+ GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6
+.ifc \operation, enc
+ # GHASH computation for the last <16 byte block
+ movdqa SHUF_MASK(%rip), %xmm10
+ # shuffle xmm0 back to output as ciphertext
+ PSHUFB_XMM %xmm10, %xmm0
+.endif
+
+ # Output %r13 bytes
+ MOVQ_R64_XMM %xmm0, %rax
+ cmp $8, %r13
+ jle _less_than_8_bytes_left_\@
+ mov %rax, (%arg2 , %r11, 1)
+ add $8, %r11
+ psrldq $8, %xmm0
+ MOVQ_R64_XMM %xmm0, %rax
+ sub $8, %r13
+_less_than_8_bytes_left_\@:
+ mov %al, (%arg2, %r11, 1)
+ add $1, %r11
+ shr $8, %rax
+ sub $1, %r13
+ jne _less_than_8_bytes_left_\@
+_multiple_of_16_bytes_\@:
+.endm
+
# GCM_COMPLETE Finishes update of tag of last partial block
# Output: Authorization Tag (AUTH_TAG)
# Clobbers rax, r10-r12, and xmm0, xmm1, xmm5-xmm15
@@ -1245,93 +1357,7 @@ ENTRY(aesni_gcm_dec)
FUNC_SAVE

GCM_INIT
-
- # Decrypt first few blocks
-
- and $(3<<4), %r12
- jz _initial_num_blocks_is_0_decrypt
- cmp $(2<<4), %r12
- jb _initial_num_blocks_is_1_decrypt
- je _initial_num_blocks_is_2_decrypt
-_initial_num_blocks_is_3_decrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 5, 678, dec
- sub $48, %r13
- jmp _initial_blocks_decrypted
-_initial_num_blocks_is_2_decrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 6, 78, dec
- sub $32, %r13
- jmp _initial_blocks_decrypted
-_initial_num_blocks_is_1_decrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 7, 8, dec
- sub $16, %r13
- jmp _initial_blocks_decrypted
-_initial_num_blocks_is_0_decrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 8, 0, dec
-_initial_blocks_decrypted:
- cmp $0, %r13
- je _zero_cipher_left_decrypt
- sub $64, %r13
- je _four_cipher_left_decrypt
-_decrypt_by_4:
- GHASH_4_ENCRYPT_4_PARALLEL_DEC %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, \
-%xmm14, %xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7, %xmm8, dec
- add $64, %r11
- sub $64, %r13
- jne _decrypt_by_4
-_four_cipher_left_decrypt:
- GHASH_LAST_4 %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, \
-%xmm15, %xmm1, %xmm2, %xmm3, %xmm4, %xmm8
-_zero_cipher_left_decrypt:
- mov %arg4, %r13
- and $15, %r13 # %r13 = arg4 (mod 16)
- je _multiple_of_16_bytes_decrypt
-
- # Handle the last <16 byte block separately
-
- paddd ONE(%rip), %xmm0 # increment CNT to get Yn
- movdqa SHUF_MASK(%rip), %xmm10
- PSHUFB_XMM %xmm10, %xmm0
-
- ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # E(K, Yn)
-
- lea (%arg3,%r11,1), %r10
- mov %r13, %r12
- READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1
-
- lea ALL_F+16(%rip), %r12
- sub %r13, %r12
- movdqa %xmm1, %xmm2
- pxor %xmm1, %xmm0 # Ciphertext XOR E(K, Yn)
- movdqu (%r12), %xmm1
- # get the appropriate mask to mask out top 16-%r13 bytes of %xmm0
- pand %xmm1, %xmm0 # mask out top 16-%r13 bytes of %xmm0
- pand %xmm1, %xmm2
- movdqa SHUF_MASK(%rip), %xmm10
- PSHUFB_XMM %xmm10 ,%xmm2
-
- pxor %xmm2, %xmm8
- GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6
-
- # output %r13 bytes
- MOVQ_R64_XMM %xmm0, %rax
- cmp $8, %r13
- jle _less_than_8_bytes_left_decrypt
- mov %rax, (%arg2 , %r11, 1)
- add $8, %r11
- psrldq $8, %xmm0
- MOVQ_R64_XMM %xmm0, %rax
- sub $8, %r13
-_less_than_8_bytes_left_decrypt:
- mov %al, (%arg2, %r11, 1)
- add $1, %r11
- shr $8, %rax
- sub $1, %r13
- jne _less_than_8_bytes_left_decrypt
-_multiple_of_16_bytes_decrypt:
+ GCM_ENC_DEC dec
GCM_COMPLETE
FUNC_RESTORE
ret
@@ -1417,98 +1443,7 @@ ENTRY(aesni_gcm_enc)
FUNC_SAVE

GCM_INIT
- # Encrypt first few blocks
-
- and $(3<<4), %r12
- jz _initial_num_blocks_is_0_encrypt
- cmp $(2<<4), %r12
- jb _initial_num_blocks_is_1_encrypt
- je _initial_num_blocks_is_2_encrypt
-_initial_num_blocks_is_3_encrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 5, 678, enc
- sub $48, %r13
- jmp _initial_blocks_encrypted
-_initial_num_blocks_is_2_encrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 6, 78, enc
- sub $32, %r13
- jmp _initial_blocks_encrypted
-_initial_num_blocks_is_1_encrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 7, 8, enc
- sub $16, %r13
- jmp _initial_blocks_encrypted
-_initial_num_blocks_is_0_encrypt:
- INITIAL_BLOCKS_ENC_DEC %xmm9, %xmm10, %xmm13, %xmm11, %xmm12, %xmm0, \
-%xmm1, %xmm2, %xmm3, %xmm4, %xmm8, %xmm5, %xmm6, 8, 0, enc
-_initial_blocks_encrypted:
-
- # Main loop - Encrypt remaining blocks
-
- cmp $0, %r13
- je _zero_cipher_left_encrypt
- sub $64, %r13
- je _four_cipher_left_encrypt
-_encrypt_by_4_encrypt:
- GHASH_4_ENCRYPT_4_PARALLEL_ENC %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, \
-%xmm14, %xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7, %xmm8, enc
- add $64, %r11
- sub $64, %r13
- jne _encrypt_by_4_encrypt
-_four_cipher_left_encrypt:
- GHASH_LAST_4 %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, \
-%xmm15, %xmm1, %xmm2, %xmm3, %xmm4, %xmm8
-_zero_cipher_left_encrypt:
- mov %arg4, %r13
- and $15, %r13 # %r13 = arg4 (mod 16)
- je _multiple_of_16_bytes_encrypt
-
- # Handle the last <16 Byte block separately
- paddd ONE(%rip), %xmm0 # INCR CNT to get Yn
- movdqa SHUF_MASK(%rip), %xmm10
- PSHUFB_XMM %xmm10, %xmm0
-
- ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # Encrypt(K, Yn)
-
- lea (%arg3,%r11,1), %r10
- mov %r13, %r12
- READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1
-
- lea ALL_F+16(%rip), %r12
- sub %r13, %r12
- pxor %xmm1, %xmm0 # Plaintext XOR Encrypt(K, Yn)
- movdqu (%r12), %xmm1
- # get the appropriate mask to mask out top 16-r13 bytes of xmm0
- pand %xmm1, %xmm0 # mask out top 16-r13 bytes of xmm0
- movdqa SHUF_MASK(%rip), %xmm10
- PSHUFB_XMM %xmm10,%xmm0
-
- pxor %xmm0, %xmm8
- GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6
- # GHASH computation for the last <16 byte block
- movdqa SHUF_MASK(%rip), %xmm10
- PSHUFB_XMM %xmm10, %xmm0
-
- # shuffle xmm0 back to output as ciphertext
-
- # Output %r13 bytes
- MOVQ_R64_XMM %xmm0, %rax
- cmp $8, %r13
- jle _less_than_8_bytes_left_encrypt
- mov %rax, (%arg2 , %r11, 1)
- add $8, %r11
- psrldq $8, %xmm0
- MOVQ_R64_XMM %xmm0, %rax
- sub $8, %r13
-_less_than_8_bytes_left_encrypt:
- mov %al, (%arg2, %r11, 1)
- add $1, %r11
- shr $8, %rax
- sub $1, %r13
- jne _less_than_8_bytes_left_encrypt
-_multiple_of_16_bytes_encrypt:
-_return_T_encrypt:
+ GCM_ENC_DEC enc
GCM_COMPLETE
FUNC_RESTORE
ret
--
2.9.5