Subject: [PATCH v2 34/35] lib/crypto: aes: Remove old AES en/decryption functions

From: Eric Biggers <[email-masked]>
Date: Mon, 12 Jan 2026 11:20:32 -0800

Now that all callers of the aes_encrypt() and aes_decrypt() type-generic
macros are using the new types, remove the old functions.

Then, replace the macro with direct calls to the new functions, dropping
the "_new" suffix from them.

This completes the change in the type of the key struct that is passed
to aes_encrypt() and aes_decrypt().

Acked-by: Ard Biesheuvel <[email-masked]>
Signed-off-by: Eric Biggers <[email-masked]>
---
 include/crypto/aes.h |  24 ++-------
 lib/crypto/aes.c     | 118 +++----------------------------------------
 2 files changed, 10 insertions(+), 132 deletions(-)

diff --git a/include/crypto/aes.h b/include/crypto/aes.h
index 4cb3c27d1bf5..cbf1cc96db52 100644
--- a/include/crypto/aes.h
+++ b/include/crypto/aes.h
@@ -306,39 +306,23 @@ typedef union {
  * @out: Buffer to store the ciphertext block
  * @in: Buffer containing the plaintext block
  *
  * Context: Any context.
  */
-#define aes_encrypt(key, out, in) \
-	_Generic((key), \
-		 struct crypto_aes_ctx *: aes_encrypt_old((const struct crypto_aes_ctx *)(key), (out), (in)), \
-		 const struct crypto_aes_ctx *: aes_encrypt_old((const struct crypto_aes_ctx *)(key), (out), (in)), \
-		 struct aes_enckey *: aes_encrypt_new((const struct aes_enckey *)(key), (out), (in)), \
-		 const struct aes_enckey *: aes_encrypt_new((const struct aes_enckey *)(key), (out), (in)), \
-		 struct aes_key *: aes_encrypt_new((const struct aes_key *)(key), (out), (in)), \
-		 const struct aes_key *: aes_encrypt_new((const struct aes_key *)(key), (out), (in)))
-void aes_encrypt_old(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
-void aes_encrypt_new(aes_encrypt_arg key, u8 out[at_least AES_BLOCK_SIZE],
-		     const u8 in[at_least AES_BLOCK_SIZE]);
+void aes_encrypt(aes_encrypt_arg key, u8 out[at_least AES_BLOCK_SIZE],
+		 const u8 in[at_least AES_BLOCK_SIZE]);
 
 /**
  * aes_decrypt() - Decrypt a single AES block
  * @key: The AES key, previously initialized by aes_preparekey()
  * @out: Buffer to store the plaintext block
  * @in: Buffer containing the ciphertext block
  *
  * Context: Any context.
  */
-#define aes_decrypt(key, out, in) \
-	_Generic((key), \
-		 struct crypto_aes_ctx *: aes_decrypt_old((const struct crypto_aes_ctx *)(key), (out), (in)), \
-		 const struct crypto_aes_ctx *: aes_decrypt_old((const struct crypto_aes_ctx *)(key), (out), (in)), \
-		 struct aes_key *: aes_decrypt_new((const struct aes_key *)(key), (out), (in)), \
-		 const struct aes_key *: aes_decrypt_new((const struct aes_key *)(key), (out), (in)))
-void aes_decrypt_old(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
-void aes_decrypt_new(const struct aes_key *key, u8 out[at_least AES_BLOCK_SIZE],
-		     const u8 in[at_least AES_BLOCK_SIZE]);
+void aes_decrypt(const struct aes_key *key, u8 out[at_least AES_BLOCK_SIZE],
+		 const u8 in[at_least AES_BLOCK_SIZE]);
 
 extern const u8 crypto_aes_sbox[];
 extern const u8 crypto_aes_inv_sbox[];
 extern const u32 aes_enc_tab[256];
 extern const u32 aes_dec_tab[256];
diff --git a/lib/crypto/aes.c b/lib/crypto/aes.c
index 88da68dcf5a8..b7ab2d0c4e59 100644
--- a/lib/crypto/aes.c
+++ b/lib/crypto/aes.c
@@ -249,26 +249,10 @@ static u32 inv_mix_columns(u32 x)
 	u32 y = mul_by_x2(x);
 
 	return mix_columns(x ^ y ^ ror32(y, 16));
 }
 
-static __always_inline u32 subshift(u32 in[], int pos)
-{
-	return (aes_sbox[in[pos] & 0xff]) ^
-	       (aes_sbox[(in[(pos + 1) % 4] >>  8) & 0xff] <<  8) ^
-	       (aes_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^
-	       (aes_sbox[(in[(pos + 3) % 4] >> 24) & 0xff] << 24);
-}
-
-static __always_inline u32 inv_subshift(u32 in[], int pos)
-{
-	return (aes_inv_sbox[in[pos] & 0xff]) ^
-	       (aes_inv_sbox[(in[(pos + 3) % 4] >>  8) & 0xff] <<  8) ^
-	       (aes_inv_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^
-	       (aes_inv_sbox[(in[(pos + 1) % 4] >> 24) & 0xff] << 24);
-}
-
 static u32 subw(u32 in)
 {
 	return (aes_sbox[in & 0xff]) ^
 	       (aes_sbox[(in >>  8) & 0xff] <<  8) ^
 	       (aes_sbox[(in >> 16) & 0xff] << 16) ^
@@ -343,55 +327,10 @@ int aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
 	aes_expandkey_generic(ctx->key_enc, ctx->key_dec, in_key, key_len);
 	return 0;
 }
 EXPORT_SYMBOL(aes_expandkey);
 
-void aes_encrypt_old(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in)
-{
-	const u32 *rkp = ctx->key_enc + 4;
-	int rounds = 6 + ctx->key_length / 4;
-	u32 st0[4], st1[4];
-	int round;
-
-	st0[0] = ctx->key_enc[0] ^ get_unaligned_le32(in);
-	st0[1] = ctx->key_enc[1] ^ get_unaligned_le32(in + 4);
-	st0[2] = ctx->key_enc[2] ^ get_unaligned_le32(in + 8);
-	st0[3] = ctx->key_enc[3] ^ get_unaligned_le32(in + 12);
-
-	/*
-	 * Force the compiler to emit data independent Sbox references,
-	 * by xoring the input with Sbox values that are known to add up
-	 * to zero. This pulls the entire Sbox into the D-cache before any
-	 * data dependent lookups are done.
-	 */
-	st0[0] ^= aes_sbox[ 0] ^ aes_sbox[ 64] ^ aes_sbox[134] ^ aes_sbox[195];
-	st0[1] ^= aes_sbox[16] ^ aes_sbox[ 82] ^ aes_sbox[158] ^ aes_sbox[221];
-	st0[2] ^= aes_sbox[32] ^ aes_sbox[ 96] ^ aes_sbox[160] ^ aes_sbox[234];
-	st0[3] ^= aes_sbox[48] ^ aes_sbox[112] ^ aes_sbox[186] ^ aes_sbox[241];
-
-	for (round = 0;; round += 2, rkp += 8) {
-		st1[0] = mix_columns(subshift(st0, 0)) ^ rkp[0];
-		st1[1] = mix_columns(subshift(st0, 1)) ^ rkp[1];
-		st1[2] = mix_columns(subshift(st0, 2)) ^ rkp[2];
-		st1[3] = mix_columns(subshift(st0, 3)) ^ rkp[3];
-
-		if (round == rounds - 2)
-			break;
-
-		st0[0] = mix_columns(subshift(st1, 0)) ^ rkp[4];
-		st0[1] = mix_columns(subshift(st1, 1)) ^ rkp[5];
-		st0[2] = mix_columns(subshift(st1, 2)) ^ rkp[6];
-		st0[3] = mix_columns(subshift(st1, 3)) ^ rkp[7];
-	}
-
-	put_unaligned_le32(subshift(st1, 0) ^ rkp[4], out);
-	put_unaligned_le32(subshift(st1, 1) ^ rkp[5], out + 4);
-	put_unaligned_le32(subshift(st1, 2) ^ rkp[6], out + 8);
-	put_unaligned_le32(subshift(st1, 3) ^ rkp[7], out + 12);
-}
-EXPORT_SYMBOL(aes_encrypt_old);
-
 static __always_inline u32 enc_quarterround(const u32 w[4], int i, u32 rk)
 {
 	return rk ^ aes_enc_tab[(u8)w[i]] ^
 	       rol32(aes_enc_tab[(u8)(w[(i + 1) % 4] >> 8)], 8) ^
 	       rol32(aes_enc_tab[(u8)(w[(i + 2) % 4] >> 16)], 16) ^
@@ -496,55 +435,10 @@ static void __maybe_unused aes_decrypt_generic(const u32 inv_rndkeys[],
 	put_unaligned_le32(declast_quarterround(w, 1, *rkp++), &out[4]);
 	put_unaligned_le32(declast_quarterround(w, 2, *rkp++), &out[8]);
 	put_unaligned_le32(declast_quarterround(w, 3, *rkp++), &out[12]);
 }
 
-void aes_decrypt_old(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in)
-{
-	const u32 *rkp = ctx->key_dec + 4;
-	int rounds = 6 + ctx->key_length / 4;
-	u32 st0[4], st1[4];
-	int round;
-
-	st0[0] = ctx->key_dec[0] ^ get_unaligned_le32(in);
-	st0[1] = ctx->key_dec[1] ^ get_unaligned_le32(in + 4);
-	st0[2] = ctx->key_dec[2] ^ get_unaligned_le32(in + 8);
-	st0[3] = ctx->key_dec[3] ^ get_unaligned_le32(in + 12);
-
-	/*
-	 * Force the compiler to emit data independent Sbox references,
-	 * by xoring the input with Sbox values that are known to add up
-	 * to zero. This pulls the entire Sbox into the D-cache before any
-	 * data dependent lookups are done.
-	 */
-	st0[0] ^= aes_inv_sbox[ 0] ^ aes_inv_sbox[ 64] ^ aes_inv_sbox[129] ^ aes_inv_sbox[200];
-	st0[1] ^= aes_inv_sbox[16] ^ aes_inv_sbox[ 83] ^ aes_inv_sbox[150] ^ aes_inv_sbox[212];
-	st0[2] ^= aes_inv_sbox[32] ^ aes_inv_sbox[ 96] ^ aes_inv_sbox[160] ^ aes_inv_sbox[236];
-	st0[3] ^= aes_inv_sbox[48] ^ aes_inv_sbox[112] ^ aes_inv_sbox[187] ^ aes_inv_sbox[247];
-
-	for (round = 0;; round += 2, rkp += 8) {
-		st1[0] = inv_mix_columns(inv_subshift(st0, 0)) ^ rkp[0];
-		st1[1] = inv_mix_columns(inv_subshift(st0, 1)) ^ rkp[1];
-		st1[2] = inv_mix_columns(inv_subshift(st0, 2)) ^ rkp[2];
-		st1[3] = inv_mix_columns(inv_subshift(st0, 3)) ^ rkp[3];
-
-		if (round == rounds - 2)
-			break;
-
-		st0[0] = inv_mix_columns(inv_subshift(st1, 0)) ^ rkp[4];
-		st0[1] = inv_mix_columns(inv_subshift(st1, 1)) ^ rkp[5];
-		st0[2] = inv_mix_columns(inv_subshift(st1, 2)) ^ rkp[6];
-		st0[3] = inv_mix_columns(inv_subshift(st1, 3)) ^ rkp[7];
-	}
-
-	put_unaligned_le32(inv_subshift(st1, 0) ^ rkp[4], out);
-	put_unaligned_le32(inv_subshift(st1, 1) ^ rkp[5], out + 4);
-	put_unaligned_le32(inv_subshift(st1, 2) ^ rkp[6], out + 8);
-	put_unaligned_le32(inv_subshift(st1, 3) ^ rkp[7], out + 12);
-}
-EXPORT_SYMBOL(aes_decrypt_old);
-
 /*
  * Note: the aes_prepare*key_* names reflect the fact that the implementation
  * might not actually expand the key.  (The s390 code for example doesn't.)
  * Where the key is expanded we use the more specific names aes_expandkey_*.
  *
@@ -606,23 +500,23 @@ int aes_prepareenckey(struct aes_enckey *key, const u8 *in_key, size_t key_len)
 {
 	return __aes_preparekey(key, NULL, in_key, key_len);
 }
 EXPORT_SYMBOL(aes_prepareenckey);
 
-void aes_encrypt_new(aes_encrypt_arg key, u8 out[AES_BLOCK_SIZE],
-		     const u8 in[AES_BLOCK_SIZE])
+void aes_encrypt(aes_encrypt_arg key, u8 out[AES_BLOCK_SIZE],
+		 const u8 in[AES_BLOCK_SIZE])
 {
 	aes_encrypt_arch(key.enc_key, out, in);
 }
-EXPORT_SYMBOL(aes_encrypt_new);
+EXPORT_SYMBOL(aes_encrypt);
 
-void aes_decrypt_new(const struct aes_key *key, u8 out[AES_BLOCK_SIZE],
-		     const u8 in[AES_BLOCK_SIZE])
+void aes_decrypt(const struct aes_key *key, u8 out[AES_BLOCK_SIZE],
+		 const u8 in[AES_BLOCK_SIZE])
 {
 	aes_decrypt_arch(key, out, in);
 }
-EXPORT_SYMBOL(aes_decrypt_new);
+EXPORT_SYMBOL(aes_decrypt);
 
 #ifdef aes_mod_init_arch
 static int __init aes_mod_init(void)
 {
 	aes_mod_init_arch();
-- 
2.52.0