iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted

isl29501_register_write() was returning a u32 instead of an int.
Since the function returns negative error codes (such as -ERANGE or
return values from i2c_smbus_write_byte_data()), returning an unsigned
integer type prevents callers from correctly checking for negative error
conditions.

Fix this by changing the function return type from u32 to int.

This was found through manual code review.

Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 208 insertions, 0 deletions

diff --git a/crypto/xcbc.c b/crypto/xcbc.c
new file mode 100644
index 000000000..6c5f6766f
--- /dev/null
+++ b/crypto/xcbc.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C)2006 USAGI/WIDE Project
+ *
+ * Author:
+ * 	Kazunori Miyazawa <miyazawa@linux-ipv6.org>
+ */
+
+#include <crypto/internal/cipher.h>
+#include <crypto/internal/hash.h>
+#include <crypto/utils.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101,
+			   0x02020202, 0x02020202, 0x02020202, 0x02020202,
+			   0x03030303, 0x03030303, 0x03030303, 0x03030303};
+
+/*
+ * +------------------------
+ * | <parent tfm>
+ * +------------------------
+ * | xcbc_tfm_ctx
+ * +------------------------
+ * | consts (block size * 2)
+ * +------------------------
+ */
+struct xcbc_tfm_ctx {
+	struct crypto_cipher *child;
+	u8 consts[];
+};
+
+#define XCBC_BLOCKSIZE	16
+
+static int crypto_xcbc_digest_setkey(struct crypto_shash *parent,
+				     const u8 *inkey, unsigned int keylen)
+{
+	struct xcbc_tfm_ctx *ctx = crypto_shash_ctx(parent);
+	u8 *consts = ctx->consts;
+	int err = 0;
+	u8 key1[XCBC_BLOCKSIZE];
+	int bs = sizeof(key1);
+
+	if ((err = crypto_cipher_setkey(ctx->child, inkey, keylen)))
+		return err;
+
+	crypto_cipher_encrypt_one(ctx->child, consts, (u8 *)ks + bs);
+	crypto_cipher_encrypt_one(ctx->child, consts + bs, (u8 *)ks + bs * 2);
+	crypto_cipher_encrypt_one(ctx->child, key1, (u8 *)ks);
+
+	return crypto_cipher_setkey(ctx->child, key1, bs);
+
+}
+
+static int crypto_xcbc_digest_init(struct shash_desc *pdesc)
+{
+	int bs = crypto_shash_blocksize(pdesc->tfm);
+	u8 *prev = shash_desc_ctx(pdesc);
+
+	memset(prev, 0, bs);
+	return 0;
+}
+
+static int crypto_xcbc_digest_update(struct shash_desc *pdesc, const u8 *p,
+				     unsigned int len)
+{
+	struct crypto_shash *parent = pdesc->tfm;
+	struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent);
+	struct crypto_cipher *tfm = tctx->child;
+	int bs = crypto_shash_blocksize(parent);
+	u8 *prev = shash_desc_ctx(pdesc);
+
+	do {
+		crypto_xor(prev, p, bs);
+		crypto_cipher_encrypt_one(tfm, prev, prev);
+		p += bs;
+		len -= bs;
+	} while (len >= bs);
+	return len;
+}
+
+static int crypto_xcbc_digest_finup(struct shash_desc *pdesc, const u8 *src,
+				    unsigned int len, u8 *out)
+{
+	struct crypto_shash *parent = pdesc->tfm;
+	struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent);
+	struct crypto_cipher *tfm = tctx->child;
+	int bs = crypto_shash_blocksize(parent);
+	u8 *prev = shash_desc_ctx(pdesc);
+	unsigned int offset = 0;
+
+	crypto_xor(prev, src, len);
+	if (len != bs) {
+		prev[len] ^= 0x80;
+		offset += bs;
+	}
+	crypto_xor(prev, &tctx->consts[offset], bs);
+	crypto_cipher_encrypt_one(tfm, out, prev);
+	return 0;
+}
+
+static int xcbc_init_tfm(struct crypto_tfm *tfm)
+{
+	struct crypto_cipher *cipher;
+	struct crypto_instance *inst = (void *)tfm->__crt_alg;
+	struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst);
+	struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	cipher = crypto_spawn_cipher(spawn);
+	if (IS_ERR(cipher))
+		return PTR_ERR(cipher);
+
+	ctx->child = cipher;
+
+	return 0;
+};
+
+static void xcbc_exit_tfm(struct crypto_tfm *tfm)
+{
+	struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
+	crypto_free_cipher(ctx->child);
+}
+
+static int xcbc_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+	struct shash_instance *inst;
+	struct crypto_cipher_spawn *spawn;
+	struct crypto_alg *alg;
+	u32 mask;
+	int err;
+
+	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask);
+	if (err)
+		return err;
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+	spawn = shash_instance_ctx(inst);
+
+	err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),
+				 crypto_attr_alg_name(tb[1]), 0, mask);
+	if (err)
+		goto err_free_inst;
+	alg = crypto_spawn_cipher_alg(spawn);
+
+	err = -EINVAL;
+	if (alg->cra_blocksize != XCBC_BLOCKSIZE)
+		goto err_free_inst;
+
+	err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);
+	if (err)
+		goto err_free_inst;
+
+	inst->alg.base.cra_priority = alg->cra_priority;
+	inst->alg.base.cra_blocksize = alg->cra_blocksize;
+	inst->alg.base.cra_ctxsize = sizeof(struct xcbc_tfm_ctx) +
+				     alg->cra_blocksize * 2;
+	inst->alg.base.cra_flags = CRYPTO_AHASH_ALG_BLOCK_ONLY |
+				   CRYPTO_AHASH_ALG_FINAL_NONZERO;
+
+	inst->alg.digestsize = alg->cra_blocksize;
+	inst->alg.descsize = alg->cra_blocksize;
+
+	inst->alg.base.cra_init = xcbc_init_tfm;
+	inst->alg.base.cra_exit = xcbc_exit_tfm;
+
+	inst->alg.init = crypto_xcbc_digest_init;
+	inst->alg.update = crypto_xcbc_digest_update;
+	inst->alg.finup = crypto_xcbc_digest_finup;
+	inst->alg.setkey = crypto_xcbc_digest_setkey;
+
+	inst->free = shash_free_singlespawn_instance;
+
+	err = shash_register_instance(tmpl, inst);
+	if (err) {
+err_free_inst:
+		shash_free_singlespawn_instance(inst);
+	}
+	return err;
+}
+
+static struct crypto_template crypto_xcbc_tmpl = {
+	.name = "xcbc",
+	.create = xcbc_create,
+	.module = THIS_MODULE,
+};
+
+static int __init crypto_xcbc_module_init(void)
+{
+	return crypto_register_template(&crypto_xcbc_tmpl);
+}
+
+static void __exit crypto_xcbc_module_exit(void)
+{
+	crypto_unregister_template(&crypto_xcbc_tmpl);
+}
+
+module_init(crypto_xcbc_module_init);
+module_exit(crypto_xcbc_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("XCBC keyed hash algorithm");
+MODULE_ALIAS_CRYPTO("xcbc");
+MODULE_IMPORT_NS("CRYPTO_INTERNAL");