From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- net/rxrpc/fcrypt.c | 352 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 352 insertions(+) create mode 100644 net/rxrpc/fcrypt.c (limited to 'net/rxrpc/fcrypt.c') diff --git a/net/rxrpc/fcrypt.c b/net/rxrpc/fcrypt.c new file mode 100644 index 000000000..a919e7598 --- /dev/null +++ b/net/rxrpc/fcrypt.c @@ -0,0 +1,352 @@ +/* FCrypt encryption algorithm + * + * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Based on code: + * + * Copyright (c) 1995 - 2000 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include "ar-internal.h" + +/* + * Sboxes for Feistel network derived from + * /afs/transarc.com/public/afsps/afs.rel31b.export-src/rxkad/sboxes.h + */ +#undef Z +#define Z(x) cpu_to_be32(x << 3) +static const __be32 sbox0[256] = { + Z(0xea), Z(0x7f), Z(0xb2), Z(0x64), Z(0x9d), Z(0xb0), Z(0xd9), Z(0x11), + Z(0xcd), Z(0x86), Z(0x86), Z(0x91), Z(0x0a), Z(0xb2), Z(0x93), Z(0x06), + Z(0x0e), Z(0x06), Z(0xd2), Z(0x65), Z(0x73), Z(0xc5), Z(0x28), Z(0x60), + Z(0xf2), Z(0x20), Z(0xb5), Z(0x38), Z(0x7e), Z(0xda), Z(0x9f), Z(0xe3), + Z(0xd2), Z(0xcf), Z(0xc4), Z(0x3c), Z(0x61), Z(0xff), Z(0x4a), Z(0x4a), + Z(0x35), Z(0xac), Z(0xaa), Z(0x5f), Z(0x2b), Z(0xbb), Z(0xbc), Z(0x53), + Z(0x4e), Z(0x9d), Z(0x78), Z(0xa3), Z(0xdc), Z(0x09), Z(0x32), Z(0x10), + Z(0xc6), Z(0x6f), Z(0x66), Z(0xd6), Z(0xab), Z(0xa9), Z(0xaf), Z(0xfd), + Z(0x3b), Z(0x95), Z(0xe8), Z(0x34), Z(0x9a), Z(0x81), Z(0x72), Z(0x80), + Z(0x9c), Z(0xf3), Z(0xec), Z(0xda), Z(0x9f), Z(0x26), Z(0x76), Z(0x15), + Z(0x3e), Z(0x55), Z(0x4d), Z(0xde), Z(0x84), Z(0xee), Z(0xad), Z(0xc7), + Z(0xf1), Z(0x6b), Z(0x3d), Z(0xd3), Z(0x04), Z(0x49), Z(0xaa), Z(0x24), + Z(0x0b), Z(0x8a), Z(0x83), Z(0xba), Z(0xfa), Z(0x85), Z(0xa0), Z(0xa8), + Z(0xb1), Z(0xd4), Z(0x01), Z(0xd8), Z(0x70), Z(0x64), Z(0xf0), Z(0x51), + Z(0xd2), Z(0xc3), Z(0xa7), Z(0x75), Z(0x8c), Z(0xa5), Z(0x64), Z(0xef), + Z(0x10), Z(0x4e), Z(0xb7), Z(0xc6), Z(0x61), Z(0x03), Z(0xeb), Z(0x44), + Z(0x3d), Z(0xe5), Z(0xb3), Z(0x5b), Z(0xae), Z(0xd5), Z(0xad), Z(0x1d), + Z(0xfa), Z(0x5a), Z(0x1e), Z(0x33), Z(0xab), Z(0x93), Z(0xa2), Z(0xb7), + Z(0xe7), Z(0xa8), Z(0x45), Z(0xa4), Z(0xcd), Z(0x29), Z(0x63), Z(0x44), + Z(0xb6), Z(0x69), Z(0x7e), Z(0x2e), Z(0x62), Z(0x03), Z(0xc8), Z(0xe0), + Z(0x17), Z(0xbb), Z(0xc7), Z(0xf3), Z(0x3f), Z(0x36), Z(0xba), Z(0x71), + Z(0x8e), Z(0x97), Z(0x65), Z(0x60), Z(0x69), Z(0xb6), Z(0xf6), Z(0xe6), + Z(0x6e), Z(0xe0), Z(0x81), Z(0x59), Z(0xe8), Z(0xaf), Z(0xdd), Z(0x95), + Z(0x22), Z(0x99), Z(0xfd), Z(0x63), Z(0x19), Z(0x74), Z(0x61), Z(0xb1), + Z(0xb6), Z(0x5b), Z(0xae), Z(0x54), Z(0xb3), Z(0x70), Z(0xff), Z(0xc6), + Z(0x3b), Z(0x3e), Z(0xc1), Z(0xd7), Z(0xe1), Z(0x0e), Z(0x76), Z(0xe5), + Z(0x36), Z(0x4f), Z(0x59), Z(0xc7), Z(0x08), Z(0x6e), Z(0x82), Z(0xa6), + Z(0x93), Z(0xc4), Z(0xaa), Z(0x26), Z(0x49), Z(0xe0), Z(0x21), Z(0x64), + Z(0x07), Z(0x9f), Z(0x64), Z(0x81), Z(0x9c), Z(0xbf), Z(0xf9), Z(0xd1), + Z(0x43), Z(0xf8), Z(0xb6), Z(0xb9), Z(0xf1), Z(0x24), Z(0x75), Z(0x03), + Z(0xe4), Z(0xb0), Z(0x99), Z(0x46), Z(0x3d), Z(0xf5), Z(0xd1), Z(0x39), + Z(0x72), Z(0x12), Z(0xf6), Z(0xba), Z(0x0c), Z(0x0d), Z(0x42), Z(0x2e) +}; + +#undef Z +#define Z(x) cpu_to_be32(((x & 0x1f) << 27) | (x >> 5)) +static const __be32 sbox1[256] = { + Z(0x77), Z(0x14), Z(0xa6), Z(0xfe), Z(0xb2), Z(0x5e), Z(0x8c), Z(0x3e), + Z(0x67), Z(0x6c), Z(0xa1), Z(0x0d), Z(0xc2), Z(0xa2), Z(0xc1), Z(0x85), + Z(0x6c), Z(0x7b), Z(0x67), Z(0xc6), Z(0x23), Z(0xe3), Z(0xf2), Z(0x89), + Z(0x50), Z(0x9c), Z(0x03), Z(0xb7), Z(0x73), Z(0xe6), Z(0xe1), Z(0x39), + Z(0x31), Z(0x2c), Z(0x27), Z(0x9f), Z(0xa5), Z(0x69), Z(0x44), Z(0xd6), + Z(0x23), Z(0x83), Z(0x98), Z(0x7d), Z(0x3c), Z(0xb4), Z(0x2d), Z(0x99), + Z(0x1c), Z(0x1f), Z(0x8c), Z(0x20), Z(0x03), Z(0x7c), Z(0x5f), Z(0xad), + Z(0xf4), Z(0xfa), Z(0x95), Z(0xca), Z(0x76), Z(0x44), Z(0xcd), Z(0xb6), + Z(0xb8), Z(0xa1), Z(0xa1), Z(0xbe), Z(0x9e), Z(0x54), Z(0x8f), Z(0x0b), + Z(0x16), Z(0x74), Z(0x31), Z(0x8a), Z(0x23), Z(0x17), Z(0x04), Z(0xfa), + Z(0x79), Z(0x84), Z(0xb1), Z(0xf5), Z(0x13), Z(0xab), Z(0xb5), Z(0x2e), + Z(0xaa), Z(0x0c), Z(0x60), Z(0x6b), Z(0x5b), Z(0xc4), Z(0x4b), Z(0xbc), + Z(0xe2), Z(0xaf), Z(0x45), Z(0x73), Z(0xfa), Z(0xc9), Z(0x49), Z(0xcd), + Z(0x00), Z(0x92), Z(0x7d), Z(0x97), Z(0x7a), Z(0x18), Z(0x60), Z(0x3d), + Z(0xcf), Z(0x5b), Z(0xde), Z(0xc6), Z(0xe2), Z(0xe6), Z(0xbb), Z(0x8b), + Z(0x06), Z(0xda), Z(0x08), Z(0x15), Z(0x1b), Z(0x88), Z(0x6a), Z(0x17), + Z(0x89), Z(0xd0), Z(0xa9), Z(0xc1), Z(0xc9), Z(0x70), Z(0x6b), Z(0xe5), + Z(0x43), Z(0xf4), Z(0x68), Z(0xc8), Z(0xd3), Z(0x84), Z(0x28), Z(0x0a), + Z(0x52), Z(0x66), Z(0xa3), Z(0xca), Z(0xf2), Z(0xe3), Z(0x7f), Z(0x7a), + Z(0x31), Z(0xf7), Z(0x88), Z(0x94), Z(0x5e), Z(0x9c), Z(0x63), Z(0xd5), + Z(0x24), Z(0x66), Z(0xfc), Z(0xb3), Z(0x57), Z(0x25), Z(0xbe), Z(0x89), + Z(0x44), Z(0xc4), Z(0xe0), Z(0x8f), Z(0x23), Z(0x3c), Z(0x12), Z(0x52), + Z(0xf5), Z(0x1e), Z(0xf4), Z(0xcb), Z(0x18), Z(0x33), Z(0x1f), Z(0xf8), + Z(0x69), Z(0x10), Z(0x9d), Z(0xd3), Z(0xf7), Z(0x28), Z(0xf8), Z(0x30), + Z(0x05), Z(0x5e), Z(0x32), Z(0xc0), Z(0xd5), Z(0x19), Z(0xbd), Z(0x45), + Z(0x8b), Z(0x5b), Z(0xfd), Z(0xbc), Z(0xe2), Z(0x5c), Z(0xa9), Z(0x96), + Z(0xef), Z(0x70), Z(0xcf), Z(0xc2), Z(0x2a), Z(0xb3), Z(0x61), Z(0xad), + Z(0x80), Z(0x48), Z(0x81), Z(0xb7), Z(0x1d), Z(0x43), Z(0xd9), Z(0xd7), + Z(0x45), Z(0xf0), Z(0xd8), Z(0x8a), Z(0x59), Z(0x7c), Z(0x57), Z(0xc1), + Z(0x79), Z(0xc7), Z(0x34), Z(0xd6), Z(0x43), Z(0xdf), Z(0xe4), Z(0x78), + Z(0x16), Z(0x06), Z(0xda), Z(0x92), Z(0x76), Z(0x51), Z(0xe1), Z(0xd4), + Z(0x70), Z(0x03), Z(0xe0), Z(0x2f), Z(0x96), Z(0x91), Z(0x82), Z(0x80) +}; + +#undef Z +#define Z(x) cpu_to_be32(x << 11) +static const __be32 sbox2[256] = { + Z(0xf0), Z(0x37), Z(0x24), Z(0x53), Z(0x2a), Z(0x03), Z(0x83), Z(0x86), + Z(0xd1), Z(0xec), Z(0x50), Z(0xf0), Z(0x42), Z(0x78), Z(0x2f), Z(0x6d), + Z(0xbf), Z(0x80), Z(0x87), Z(0x27), Z(0x95), Z(0xe2), Z(0xc5), Z(0x5d), + Z(0xf9), Z(0x6f), Z(0xdb), Z(0xb4), Z(0x65), Z(0x6e), Z(0xe7), Z(0x24), + Z(0xc8), Z(0x1a), Z(0xbb), Z(0x49), Z(0xb5), Z(0x0a), Z(0x7d), Z(0xb9), + Z(0xe8), Z(0xdc), Z(0xb7), Z(0xd9), Z(0x45), Z(0x20), Z(0x1b), Z(0xce), + Z(0x59), Z(0x9d), Z(0x6b), Z(0xbd), Z(0x0e), Z(0x8f), Z(0xa3), Z(0xa9), + Z(0xbc), Z(0x74), Z(0xa6), Z(0xf6), Z(0x7f), Z(0x5f), Z(0xb1), Z(0x68), + Z(0x84), Z(0xbc), Z(0xa9), Z(0xfd), Z(0x55), Z(0x50), Z(0xe9), Z(0xb6), + Z(0x13), Z(0x5e), Z(0x07), Z(0xb8), Z(0x95), Z(0x02), Z(0xc0), Z(0xd0), + Z(0x6a), Z(0x1a), Z(0x85), Z(0xbd), Z(0xb6), Z(0xfd), Z(0xfe), Z(0x17), + Z(0x3f), Z(0x09), Z(0xa3), Z(0x8d), Z(0xfb), Z(0xed), Z(0xda), Z(0x1d), + Z(0x6d), Z(0x1c), Z(0x6c), Z(0x01), Z(0x5a), Z(0xe5), Z(0x71), Z(0x3e), + Z(0x8b), Z(0x6b), Z(0xbe), Z(0x29), Z(0xeb), Z(0x12), Z(0x19), Z(0x34), + Z(0xcd), Z(0xb3), Z(0xbd), Z(0x35), Z(0xea), Z(0x4b), Z(0xd5), Z(0xae), + Z(0x2a), Z(0x79), Z(0x5a), Z(0xa5), Z(0x32), Z(0x12), Z(0x7b), Z(0xdc), + Z(0x2c), Z(0xd0), Z(0x22), Z(0x4b), Z(0xb1), Z(0x85), Z(0x59), Z(0x80), + Z(0xc0), Z(0x30), Z(0x9f), Z(0x73), Z(0xd3), Z(0x14), Z(0x48), Z(0x40), + Z(0x07), Z(0x2d), Z(0x8f), Z(0x80), Z(0x0f), Z(0xce), Z(0x0b), Z(0x5e), + Z(0xb7), Z(0x5e), Z(0xac), Z(0x24), Z(0x94), Z(0x4a), Z(0x18), Z(0x15), + Z(0x05), Z(0xe8), Z(0x02), Z(0x77), Z(0xa9), Z(0xc7), Z(0x40), Z(0x45), + Z(0x89), Z(0xd1), Z(0xea), Z(0xde), Z(0x0c), Z(0x79), Z(0x2a), Z(0x99), + Z(0x6c), Z(0x3e), Z(0x95), Z(0xdd), Z(0x8c), Z(0x7d), Z(0xad), Z(0x6f), + Z(0xdc), Z(0xff), Z(0xfd), Z(0x62), Z(0x47), Z(0xb3), Z(0x21), Z(0x8a), + Z(0xec), Z(0x8e), Z(0x19), Z(0x18), Z(0xb4), Z(0x6e), Z(0x3d), Z(0xfd), + Z(0x74), Z(0x54), Z(0x1e), Z(0x04), Z(0x85), Z(0xd8), Z(0xbc), Z(0x1f), + Z(0x56), Z(0xe7), Z(0x3a), Z(0x56), Z(0x67), Z(0xd6), Z(0xc8), Z(0xa5), + Z(0xf3), Z(0x8e), Z(0xde), Z(0xae), Z(0x37), Z(0x49), Z(0xb7), Z(0xfa), + Z(0xc8), Z(0xf4), Z(0x1f), Z(0xe0), Z(0x2a), Z(0x9b), Z(0x15), Z(0xd1), + Z(0x34), Z(0x0e), Z(0xb5), Z(0xe0), Z(0x44), Z(0x78), Z(0x84), Z(0x59), + Z(0x56), Z(0x68), Z(0x77), Z(0xa5), Z(0x14), Z(0x06), Z(0xf5), Z(0x2f), + Z(0x8c), Z(0x8a), Z(0x73), Z(0x80), Z(0x76), Z(0xb4), Z(0x10), Z(0x86) +}; + +#undef Z +#define Z(x) cpu_to_be32(x << 19) +static const __be32 sbox3[256] = { + Z(0xa9), Z(0x2a), Z(0x48), Z(0x51), Z(0x84), Z(0x7e), Z(0x49), Z(0xe2), + Z(0xb5), Z(0xb7), Z(0x42), Z(0x33), Z(0x7d), Z(0x5d), Z(0xa6), Z(0x12), + Z(0x44), Z(0x48), Z(0x6d), Z(0x28), Z(0xaa), Z(0x20), Z(0x6d), Z(0x57), + Z(0xd6), Z(0x6b), Z(0x5d), Z(0x72), Z(0xf0), Z(0x92), Z(0x5a), Z(0x1b), + Z(0x53), Z(0x80), Z(0x24), Z(0x70), Z(0x9a), Z(0xcc), Z(0xa7), Z(0x66), + Z(0xa1), Z(0x01), Z(0xa5), Z(0x41), Z(0x97), Z(0x41), Z(0x31), Z(0x82), + Z(0xf1), Z(0x14), Z(0xcf), Z(0x53), Z(0x0d), Z(0xa0), Z(0x10), Z(0xcc), + Z(0x2a), Z(0x7d), Z(0xd2), Z(0xbf), Z(0x4b), Z(0x1a), Z(0xdb), Z(0x16), + Z(0x47), Z(0xf6), Z(0x51), Z(0x36), Z(0xed), Z(0xf3), Z(0xb9), Z(0x1a), + Z(0xa7), Z(0xdf), Z(0x29), Z(0x43), Z(0x01), Z(0x54), Z(0x70), Z(0xa4), + Z(0xbf), Z(0xd4), Z(0x0b), Z(0x53), Z(0x44), Z(0x60), Z(0x9e), Z(0x23), + Z(0xa1), Z(0x18), Z(0x68), Z(0x4f), Z(0xf0), Z(0x2f), Z(0x82), Z(0xc2), + Z(0x2a), Z(0x41), Z(0xb2), Z(0x42), Z(0x0c), Z(0xed), Z(0x0c), Z(0x1d), + Z(0x13), Z(0x3a), Z(0x3c), Z(0x6e), Z(0x35), Z(0xdc), Z(0x60), Z(0x65), + Z(0x85), Z(0xe9), Z(0x64), Z(0x02), Z(0x9a), Z(0x3f), Z(0x9f), Z(0x87), + Z(0x96), Z(0xdf), Z(0xbe), Z(0xf2), Z(0xcb), Z(0xe5), Z(0x6c), Z(0xd4), + Z(0x5a), Z(0x83), Z(0xbf), Z(0x92), Z(0x1b), Z(0x94), Z(0x00), Z(0x42), + Z(0xcf), Z(0x4b), Z(0x00), Z(0x75), Z(0xba), Z(0x8f), Z(0x76), Z(0x5f), + Z(0x5d), Z(0x3a), Z(0x4d), Z(0x09), Z(0x12), Z(0x08), Z(0x38), Z(0x95), + Z(0x17), Z(0xe4), Z(0x01), Z(0x1d), Z(0x4c), Z(0xa9), Z(0xcc), Z(0x85), + Z(0x82), Z(0x4c), Z(0x9d), Z(0x2f), Z(0x3b), Z(0x66), Z(0xa1), Z(0x34), + Z(0x10), Z(0xcd), Z(0x59), Z(0x89), Z(0xa5), Z(0x31), Z(0xcf), Z(0x05), + Z(0xc8), Z(0x84), Z(0xfa), Z(0xc7), Z(0xba), Z(0x4e), Z(0x8b), Z(0x1a), + Z(0x19), Z(0xf1), Z(0xa1), Z(0x3b), Z(0x18), Z(0x12), Z(0x17), Z(0xb0), + Z(0x98), Z(0x8d), Z(0x0b), Z(0x23), Z(0xc3), Z(0x3a), Z(0x2d), Z(0x20), + Z(0xdf), Z(0x13), Z(0xa0), Z(0xa8), Z(0x4c), Z(0x0d), Z(0x6c), Z(0x2f), + Z(0x47), Z(0x13), Z(0x13), Z(0x52), Z(0x1f), Z(0x2d), Z(0xf5), Z(0x79), + Z(0x3d), Z(0xa2), Z(0x54), Z(0xbd), Z(0x69), Z(0xc8), Z(0x6b), Z(0xf3), + Z(0x05), Z(0x28), Z(0xf1), Z(0x16), Z(0x46), Z(0x40), Z(0xb0), Z(0x11), + Z(0xd3), Z(0xb7), Z(0x95), Z(0x49), Z(0xcf), Z(0xc3), Z(0x1d), Z(0x8f), + Z(0xd8), Z(0xe1), Z(0x73), Z(0xdb), Z(0xad), Z(0xc8), Z(0xc9), Z(0xa9), + Z(0xa1), Z(0xc2), Z(0xc5), Z(0xe3), Z(0xba), Z(0xfc), Z(0x0e), Z(0x25) +}; + +union fcrypt_block { + __be64 a; + struct { + __be32 l, r; + }; +}; + +#define F_ENCRYPT(R, L, sched) \ + do { \ + union lc4 { \ + __be32 l; \ + u8 c[4]; \ + } u; \ + u.l = sched ^ R; \ + L ^= sbox0[u.c[0]] ^ sbox1[u.c[1]] ^ sbox2[u.c[2]] ^ \ + sbox3[u.c[3]]; \ + } while (0) + +/* Encrypt one block using FCrypt. */ +static __be64 fcrypt_encrypt(const struct fcrypt_key *key, __be64 ptext) +{ + union fcrypt_block X = { .a = ptext }; + + /* This is a 16 round Feistel network with permutation F_ENCRYPT. */ + F_ENCRYPT(X.r, X.l, key->sched[0x0]); + F_ENCRYPT(X.l, X.r, key->sched[0x1]); + F_ENCRYPT(X.r, X.l, key->sched[0x2]); + F_ENCRYPT(X.l, X.r, key->sched[0x3]); + F_ENCRYPT(X.r, X.l, key->sched[0x4]); + F_ENCRYPT(X.l, X.r, key->sched[0x5]); + F_ENCRYPT(X.r, X.l, key->sched[0x6]); + F_ENCRYPT(X.l, X.r, key->sched[0x7]); + F_ENCRYPT(X.r, X.l, key->sched[0x8]); + F_ENCRYPT(X.l, X.r, key->sched[0x9]); + F_ENCRYPT(X.r, X.l, key->sched[0xa]); + F_ENCRYPT(X.l, X.r, key->sched[0xb]); + F_ENCRYPT(X.r, X.l, key->sched[0xc]); + F_ENCRYPT(X.l, X.r, key->sched[0xd]); + F_ENCRYPT(X.r, X.l, key->sched[0xe]); + F_ENCRYPT(X.l, X.r, key->sched[0xf]); + return X.a; +} + +/* Decrypt one block using FCrypt. */ +static __be64 fcrypt_decrypt(const struct fcrypt_key *key, __be64 ctext) +{ + union fcrypt_block X = { .a = ctext }; + + /* This is a 16 round Feistel network with permutation F_ENCRYPT. */ + F_ENCRYPT(X.l, X.r, key->sched[0xf]); + F_ENCRYPT(X.r, X.l, key->sched[0xe]); + F_ENCRYPT(X.l, X.r, key->sched[0xd]); + F_ENCRYPT(X.r, X.l, key->sched[0xc]); + F_ENCRYPT(X.l, X.r, key->sched[0xb]); + F_ENCRYPT(X.r, X.l, key->sched[0xa]); + F_ENCRYPT(X.l, X.r, key->sched[0x9]); + F_ENCRYPT(X.r, X.l, key->sched[0x8]); + F_ENCRYPT(X.l, X.r, key->sched[0x7]); + F_ENCRYPT(X.r, X.l, key->sched[0x6]); + F_ENCRYPT(X.l, X.r, key->sched[0x5]); + F_ENCRYPT(X.r, X.l, key->sched[0x4]); + F_ENCRYPT(X.l, X.r, key->sched[0x3]); + F_ENCRYPT(X.r, X.l, key->sched[0x2]); + F_ENCRYPT(X.l, X.r, key->sched[0x1]); + F_ENCRYPT(X.r, X.l, key->sched[0x0]); + return X.a; +} + +/** + * fcrypt_preparekey - Prepare a key for FCrypt encryption and decryption + * @key: (out) The prepared key + * @raw_key: The raw key as an 8-byte array + * + * This computes the FCrypt key schedule. + */ +void fcrypt_preparekey(struct fcrypt_key *key, const u8 raw_key[FCRYPT_BSIZE]) +{ + u64 k = 0; + + /* Load the 56 non-parity bits of the key. Discard the parity bits. */ + for (int i = 0; i < 8; i++) + k = (k << 7) | (raw_key[i] >> 1); + + /* Generate the key schedule word for each round. */ + for (int i = 0; i < FCRYPT_ROUNDS; i++) { + key->sched[i] = cpu_to_be32(k); + /* Rotate the low 56 bits of 'k' right by 11 bits. */ + k = (k >> 11) | ((k & ((1 << 11) - 1)) << (56 - 11)); + } +} +EXPORT_SYMBOL_IF_KUNIT(fcrypt_preparekey); + +/** + * fcrypt_pcbc_encrypt - Encrypt data using FCrypt cipher in PCBC mode + * @key: The key + * @iv: The 8-byte initialization vector + * @src: The source data + * @dst: The destination data. Both in-place and out-of-place are supported. + * @nblocks: The number of 8-byte blocks to encrypt + * + * WARNING: This cipher is insecure. Not only is the 56-bit key easily + * brute-forced, the cipher itself is cryptographically weak and doesn't even + * provide the intended 56-bit security level. It effectively just acts as an + * obfuscation algorithm. It is supported only for backwards compatibility. + */ +void fcrypt_pcbc_encrypt(const struct fcrypt_key *key, + const u8 iv[FCRYPT_BSIZE], const void *src, void *dst, + size_t nblocks) +{ + __be64 prev = get_unaligned((const __be64 *)iv); + const __be64 *src_blocks = src; + __be64 *dst_blocks = dst; + + while (nblocks--) { + __be64 ptext, ctext; + + ptext = get_unaligned(src_blocks++); + ctext = fcrypt_encrypt(key, prev ^ ptext); + put_unaligned(ctext, dst_blocks++); + prev = ptext ^ ctext; + } +} +EXPORT_SYMBOL_IF_KUNIT(fcrypt_pcbc_encrypt); + +/** + * fcrypt_pcbc_decrypt - Decrypt data using FCrypt cipher in PCBC mode + * @key: The key + * @iv: The 8-byte initialization vector + * @src: The source data + * @dst: The destination data. Both in-place and out-of-place are supported. + * @nblocks: The number of 8-byte blocks to decrypt + */ +void fcrypt_pcbc_decrypt(const struct fcrypt_key *key, + const u8 iv[FCRYPT_BSIZE], const void *src, void *dst, + size_t nblocks) +{ + __be64 prev = get_unaligned((const __be64 *)iv); + const __be64 *src_blocks = src; + __be64 *dst_blocks = dst; + + while (nblocks--) { + __be64 ptext, ctext; + + ctext = get_unaligned(src_blocks++); + ptext = prev ^ fcrypt_decrypt(key, ctext); + put_unaligned(ptext, dst_blocks++); + prev = ptext ^ ctext; + } +} +EXPORT_SYMBOL_IF_KUNIT(fcrypt_pcbc_decrypt); -- cgit v1.3.1