.fpu            neon
        .align          5
 
-ENTRY(chacha20_block_xor_neon)
-       // r0: Input state matrix, s
-       // r1: 1 data block output, o
-       // r2: 1 data block input, i
-
-       //
-       // This function encrypts one ChaCha20 block by loading the state matrix
-       // in four NEON registers. It performs matrix operation on four words in
-       // parallel, but requireds shuffling to rearrange the words after each
-       // round.
-       //
-
-       // x0..3 = s0..3
-       add             ip, r0, #0x20
-       vld1.32         {q0-q1}, [r0]
-       vld1.32         {q2-q3}, [ip]
-
-       vmov            q8, q0
-       vmov            q9, q1
-       vmov            q10, q2
-       vmov            q11, q3
+/*
+ * chacha20_permute - permute one block
+ *
+ * Permute one 64-byte block where the state matrix is stored in the four NEON
+ * registers q0-q3.  It performs matrix operations on four words in parallel,
+ * but requires shuffling to rearrange the words after each round.
+ *
+ * Clobbers: r3, ip, q4-q5
+ */
+chacha20_permute:
 
        adr             ip, .Lrol8_table
        mov             r3, #10
        subs            r3, r3, #1
        bne             .Ldoubleround
 
+       bx              lr
+ENDPROC(chacha20_permute)
+
+ENTRY(chacha20_block_xor_neon)
+       // r0: Input state matrix, s
+       // r1: 1 data block output, o
+       // r2: 1 data block input, i
+       push            {lr}
+
+       // x0..3 = s0..3
+       add             ip, r0, #0x20
+       vld1.32         {q0-q1}, [r0]
+       vld1.32         {q2-q3}, [ip]
+
+       vmov            q8, q0
+       vmov            q9, q1
+       vmov            q10, q2
+       vmov            q11, q3
+
+       bl              chacha20_permute
+
        add             ip, r2, #0x20
        vld1.8          {q4-q5}, [r2]
        vld1.8          {q6-q7}, [ip]
        vst1.8          {q0-q1}, [r1]
        vst1.8          {q2-q3}, [ip]
 
-       bx              lr
+       pop             {pc}
 ENDPROC(chacha20_block_xor_neon)
 
+ENTRY(hchacha20_block_neon)
+       // r0: Input state matrix, s
+       // r1: output (8 32-bit words)
+       push            {lr}
+
+       vld1.32         {q0-q1}, [r0]!
+       vld1.32         {q2-q3}, [r0]
+
+       bl              chacha20_permute
+
+       vst1.32         {q0}, [r1]!
+       vst1.32         {q3}, [r1]
+
+       pop             {pc}
+ENDPROC(hchacha20_block_neon)
+
        .align          4
 .Lctrinc:      .word   0, 1, 2, 3
 .Lrol8_table:  .byte   3, 0, 1, 2, 7, 4, 5, 6
 
 /*
- * ChaCha20 256-bit cipher algorithm, RFC7539, ARM NEON functions
+ * ChaCha20 (RFC7539) and XChaCha20 stream ciphers, NEON accelerated
  *
  * Copyright (C) 2016 Linaro, Ltd. <ard.biesheuvel@linaro.org>
  *
 
 asmlinkage void chacha20_block_xor_neon(u32 *state, u8 *dst, const u8 *src);
 asmlinkage void chacha20_4block_xor_neon(u32 *state, u8 *dst, const u8 *src);
+asmlinkage void hchacha20_block_neon(const u32 *state, u32 *out);
 
 static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src,
                            unsigned int bytes)
        }
 }
 
-static int chacha20_neon(struct skcipher_request *req)
+static int chacha20_neon_stream_xor(struct skcipher_request *req,
+                                   struct chacha_ctx *ctx, u8 *iv)
 {
-       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
-       struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_walk walk;
        u32 state[16];
        int err;
 
-       if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd())
-               return crypto_chacha_crypt(req);
-
        err = skcipher_walk_virt(&walk, req, false);
 
-       crypto_chacha_init(state, ctx, walk.iv);
+       crypto_chacha_init(state, ctx, iv);
 
        while (walk.nbytes > 0) {
                unsigned int nbytes = walk.nbytes;
        return err;
 }
 
-static struct skcipher_alg alg = {
-       .base.cra_name          = "chacha20",
-       .base.cra_driver_name   = "chacha20-neon",
-       .base.cra_priority      = 300,
-       .base.cra_blocksize     = 1,
-       .base.cra_ctxsize       = sizeof(struct chacha_ctx),
-       .base.cra_module        = THIS_MODULE,
-
-       .min_keysize            = CHACHA_KEY_SIZE,
-       .max_keysize            = CHACHA_KEY_SIZE,
-       .ivsize                 = CHACHA_IV_SIZE,
-       .chunksize              = CHACHA_BLOCK_SIZE,
-       .walksize               = 4 * CHACHA_BLOCK_SIZE,
-       .setkey                 = crypto_chacha20_setkey,
-       .encrypt                = chacha20_neon,
-       .decrypt                = chacha20_neon,
+static int chacha20_neon(struct skcipher_request *req)
+{
+       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+       struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+       if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd())
+               return crypto_chacha_crypt(req);
+
+       return chacha20_neon_stream_xor(req, ctx, req->iv);
+}
+
+static int xchacha20_neon(struct skcipher_request *req)
+{
+       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+       struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
+       struct chacha_ctx subctx;
+       u32 state[16];
+       u8 real_iv[16];
+
+       if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd())
+               return crypto_xchacha_crypt(req);
+
+       crypto_chacha_init(state, ctx, req->iv);
+
+       kernel_neon_begin();
+       hchacha20_block_neon(state, subctx.key);
+       kernel_neon_end();
+
+       memcpy(&real_iv[0], req->iv + 24, 8);
+       memcpy(&real_iv[8], req->iv + 16, 8);
+       return chacha20_neon_stream_xor(req, &subctx, real_iv);
+}
+
+static struct skcipher_alg algs[] = {
+       {
+               .base.cra_name          = "chacha20",
+               .base.cra_driver_name   = "chacha20-neon",
+               .base.cra_priority      = 300,
+               .base.cra_blocksize     = 1,
+               .base.cra_ctxsize       = sizeof(struct chacha_ctx),
+               .base.cra_module        = THIS_MODULE,
+
+               .min_keysize            = CHACHA_KEY_SIZE,
+               .max_keysize            = CHACHA_KEY_SIZE,
+               .ivsize                 = CHACHA_IV_SIZE,
+               .chunksize              = CHACHA_BLOCK_SIZE,
+               .walksize               = 4 * CHACHA_BLOCK_SIZE,
+               .setkey                 = crypto_chacha20_setkey,
+               .encrypt                = chacha20_neon,
+               .decrypt                = chacha20_neon,
+       }, {
+               .base.cra_name          = "xchacha20",
+               .base.cra_driver_name   = "xchacha20-neon",
+               .base.cra_priority      = 300,
+               .base.cra_blocksize     = 1,
+               .base.cra_ctxsize       = sizeof(struct chacha_ctx),
+               .base.cra_module        = THIS_MODULE,
+
+               .min_keysize            = CHACHA_KEY_SIZE,
+               .max_keysize            = CHACHA_KEY_SIZE,
+               .ivsize                 = XCHACHA_IV_SIZE,
+               .chunksize              = CHACHA_BLOCK_SIZE,
+               .walksize               = 4 * CHACHA_BLOCK_SIZE,
+               .setkey                 = crypto_chacha20_setkey,
+               .encrypt                = xchacha20_neon,
+               .decrypt                = xchacha20_neon,
+       }
 };
 
 static int __init chacha20_simd_mod_init(void)
        if (!(elf_hwcap & HWCAP_NEON))
                return -ENODEV;
 
-       return crypto_register_skcipher(&alg);
+       return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
 }
 
 static void __exit chacha20_simd_mod_fini(void)
 {
-       crypto_unregister_skcipher(&alg);
+       crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
 }
 
 module_init(chacha20_simd_mod_init);
 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
 MODULE_LICENSE("GPL v2");
 MODULE_ALIAS_CRYPTO("chacha20");
+MODULE_ALIAS_CRYPTO("chacha20-neon");
+MODULE_ALIAS_CRYPTO("xchacha20");
+MODULE_ALIAS_CRYPTO("xchacha20-neon");