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-rw-r--r--crypto/blowfish_generic.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/crypto/blowfish_generic.c b/crypto/blowfish_generic.c
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+++ b/crypto/blowfish_generic.c
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Cryptographic API.
+ *
+ * Blowfish Cipher Algorithm, by Bruce Schneier.
+ * http://www.counterpane.com/blowfish.html
+ *
+ * Adapted from Kerneli implementation.
+ *
+ * Copyright (c) Herbert Valerio Riedel <hvr@hvrlab.org>
+ * Copyright (c) Kyle McMartin <kyle@debian.org>
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ */
+
+#include <crypto/algapi.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <asm/unaligned.h>
+#include <linux/types.h>
+#include <crypto/blowfish.h>
+
+/*
+ * Round loop unrolling macros, S is a pointer to a S-Box array
+ * organized in 4 unsigned longs at a row.
+ */
+#define GET32_3(x) (((x) & 0xff))
+#define GET32_2(x) (((x) >> (8)) & (0xff))
+#define GET32_1(x) (((x) >> (16)) & (0xff))
+#define GET32_0(x) (((x) >> (24)) & (0xff))
+
+#define bf_F(x) (((S[GET32_0(x)] + S[256 + GET32_1(x)]) ^ \
+ S[512 + GET32_2(x)]) + S[768 + GET32_3(x)])
+
+#define ROUND(a, b, n) ({ b ^= P[n]; a ^= bf_F(b); })
+
+static void bf_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+ struct bf_ctx *ctx = crypto_tfm_ctx(tfm);
+ const u32 *P = ctx->p;
+ const u32 *S = ctx->s;
+ u32 yl = get_unaligned_be32(src);
+ u32 yr = get_unaligned_be32(src + 4);
+
+ ROUND(yr, yl, 0);
+ ROUND(yl, yr, 1);
+ ROUND(yr, yl, 2);
+ ROUND(yl, yr, 3);
+ ROUND(yr, yl, 4);
+ ROUND(yl, yr, 5);
+ ROUND(yr, yl, 6);
+ ROUND(yl, yr, 7);
+ ROUND(yr, yl, 8);
+ ROUND(yl, yr, 9);
+ ROUND(yr, yl, 10);
+ ROUND(yl, yr, 11);
+ ROUND(yr, yl, 12);
+ ROUND(yl, yr, 13);
+ ROUND(yr, yl, 14);
+ ROUND(yl, yr, 15);
+
+ yl ^= P[16];
+ yr ^= P[17];
+
+ put_unaligned_be32(yr, dst);
+ put_unaligned_be32(yl, dst + 4);
+}
+
+static void bf_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+ struct bf_ctx *ctx = crypto_tfm_ctx(tfm);
+ const u32 *P = ctx->p;
+ const u32 *S = ctx->s;
+ u32 yl = get_unaligned_be32(src);
+ u32 yr = get_unaligned_be32(src + 4);
+
+ ROUND(yr, yl, 17);
+ ROUND(yl, yr, 16);
+ ROUND(yr, yl, 15);
+ ROUND(yl, yr, 14);
+ ROUND(yr, yl, 13);
+ ROUND(yl, yr, 12);
+ ROUND(yr, yl, 11);
+ ROUND(yl, yr, 10);
+ ROUND(yr, yl, 9);
+ ROUND(yl, yr, 8);
+ ROUND(yr, yl, 7);
+ ROUND(yl, yr, 6);
+ ROUND(yr, yl, 5);
+ ROUND(yl, yr, 4);
+ ROUND(yr, yl, 3);
+ ROUND(yl, yr, 2);
+
+ yl ^= P[1];
+ yr ^= P[0];
+
+ put_unaligned_be32(yr, dst);
+ put_unaligned_be32(yl, dst + 4);
+}
+
+static struct crypto_alg alg = {
+ .cra_name = "blowfish",
+ .cra_driver_name = "blowfish-generic",
+ .cra_priority = 100,
+ .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
+ .cra_blocksize = BF_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct bf_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_u = { .cipher = {
+ .cia_min_keysize = BF_MIN_KEY_SIZE,
+ .cia_max_keysize = BF_MAX_KEY_SIZE,
+ .cia_setkey = blowfish_setkey,
+ .cia_encrypt = bf_encrypt,
+ .cia_decrypt = bf_decrypt } }
+};
+
+static int __init blowfish_mod_init(void)
+{
+ return crypto_register_alg(&alg);
+}
+
+static void __exit blowfish_mod_fini(void)
+{
+ crypto_unregister_alg(&alg);
+}
+
+subsys_initcall(blowfish_mod_init);
+module_exit(blowfish_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Blowfish Cipher Algorithm");
+MODULE_ALIAS_CRYPTO("blowfish");
+MODULE_ALIAS_CRYPTO("blowfish-generic");