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 --- crypto/md4.c | 241 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 241 insertions(+) create mode 100644 crypto/md4.c (limited to 'crypto/md4.c') diff --git a/crypto/md4.c b/crypto/md4.c new file mode 100644 index 000000000..55bf47e23 --- /dev/null +++ b/crypto/md4.c @@ -0,0 +1,241 @@ +/* + * Cryptographic API. + * + * MD4 Message Digest Algorithm (RFC1320). + * + * Implementation derived from Andrew Tridgell and Steve French's + * CIFS MD4 implementation, and the cryptoapi implementation + * originally based on the public domain implementation written + * by Colin Plumb in 1993. + * + * Copyright (c) Andrew Tridgell 1997-1998. + * Modified by Steve French (sfrench@us.ibm.com) 2002 + * Copyright (c) Cryptoapi developers. + * Copyright (c) 2002 David S. Miller (davem@redhat.com) + * Copyright (c) 2002 James Morris + * + * 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. + * + */ +#include +#include +#include +#include +#include +#include +#include + +#define MD4_DIGEST_SIZE 16 +#define MD4_HMAC_BLOCK_SIZE 64 +#define MD4_BLOCK_WORDS 16 +#define MD4_HASH_WORDS 4 + +struct md4_ctx { + u32 hash[MD4_HASH_WORDS]; + u32 block[MD4_BLOCK_WORDS]; + u64 byte_count; +}; + +static inline u32 lshift(u32 x, unsigned int s) +{ + x &= 0xFFFFFFFF; + return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s)); +} + +static inline u32 F(u32 x, u32 y, u32 z) +{ + return (x & y) | ((~x) & z); +} + +static inline u32 G(u32 x, u32 y, u32 z) +{ + return (x & y) | (x & z) | (y & z); +} + +static inline u32 H(u32 x, u32 y, u32 z) +{ + return x ^ y ^ z; +} + +#define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s)) +#define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s)) +#define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s)) + +static void md4_transform(u32 *hash, u32 const *in) +{ + u32 a, b, c, d; + + a = hash[0]; + b = hash[1]; + c = hash[2]; + d = hash[3]; + + ROUND1(a, b, c, d, in[0], 3); + ROUND1(d, a, b, c, in[1], 7); + ROUND1(c, d, a, b, in[2], 11); + ROUND1(b, c, d, a, in[3], 19); + ROUND1(a, b, c, d, in[4], 3); + ROUND1(d, a, b, c, in[5], 7); + ROUND1(c, d, a, b, in[6], 11); + ROUND1(b, c, d, a, in[7], 19); + ROUND1(a, b, c, d, in[8], 3); + ROUND1(d, a, b, c, in[9], 7); + ROUND1(c, d, a, b, in[10], 11); + ROUND1(b, c, d, a, in[11], 19); + ROUND1(a, b, c, d, in[12], 3); + ROUND1(d, a, b, c, in[13], 7); + ROUND1(c, d, a, b, in[14], 11); + ROUND1(b, c, d, a, in[15], 19); + + ROUND2(a, b, c, d,in[ 0], 3); + ROUND2(d, a, b, c, in[4], 5); + ROUND2(c, d, a, b, in[8], 9); + ROUND2(b, c, d, a, in[12], 13); + ROUND2(a, b, c, d, in[1], 3); + ROUND2(d, a, b, c, in[5], 5); + ROUND2(c, d, a, b, in[9], 9); + ROUND2(b, c, d, a, in[13], 13); + ROUND2(a, b, c, d, in[2], 3); + ROUND2(d, a, b, c, in[6], 5); + ROUND2(c, d, a, b, in[10], 9); + ROUND2(b, c, d, a, in[14], 13); + ROUND2(a, b, c, d, in[3], 3); + ROUND2(d, a, b, c, in[7], 5); + ROUND2(c, d, a, b, in[11], 9); + ROUND2(b, c, d, a, in[15], 13); + + ROUND3(a, b, c, d,in[ 0], 3); + ROUND3(d, a, b, c, in[8], 9); + ROUND3(c, d, a, b, in[4], 11); + ROUND3(b, c, d, a, in[12], 15); + ROUND3(a, b, c, d, in[2], 3); + ROUND3(d, a, b, c, in[10], 9); + ROUND3(c, d, a, b, in[6], 11); + ROUND3(b, c, d, a, in[14], 15); + ROUND3(a, b, c, d, in[1], 3); + ROUND3(d, a, b, c, in[9], 9); + ROUND3(c, d, a, b, in[5], 11); + ROUND3(b, c, d, a, in[13], 15); + ROUND3(a, b, c, d, in[3], 3); + ROUND3(d, a, b, c, in[11], 9); + ROUND3(c, d, a, b, in[7], 11); + ROUND3(b, c, d, a, in[15], 15); + + hash[0] += a; + hash[1] += b; + hash[2] += c; + hash[3] += d; +} + +static inline void md4_transform_helper(struct md4_ctx *ctx) +{ + le32_to_cpu_array(ctx->block, ARRAY_SIZE(ctx->block)); + md4_transform(ctx->hash, ctx->block); +} + +static int md4_init(struct shash_desc *desc) +{ + struct md4_ctx *mctx = shash_desc_ctx(desc); + + mctx->hash[0] = 0x67452301; + mctx->hash[1] = 0xefcdab89; + mctx->hash[2] = 0x98badcfe; + mctx->hash[3] = 0x10325476; + mctx->byte_count = 0; + + return 0; +} + +static int md4_update(struct shash_desc *desc, const u8 *data, unsigned int len) +{ + struct md4_ctx *mctx = shash_desc_ctx(desc); + const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); + + mctx->byte_count += len; + + if (avail > len) { + memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), + data, len); + return 0; + } + + memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), + data, avail); + + md4_transform_helper(mctx); + data += avail; + len -= avail; + + while (len >= sizeof(mctx->block)) { + memcpy(mctx->block, data, sizeof(mctx->block)); + md4_transform_helper(mctx); + data += sizeof(mctx->block); + len -= sizeof(mctx->block); + } + + memcpy(mctx->block, data, len); + + return 0; +} + +static int md4_final(struct shash_desc *desc, u8 *out) +{ + struct md4_ctx *mctx = shash_desc_ctx(desc); + const unsigned int offset = mctx->byte_count & 0x3f; + char *p = (char *)mctx->block + offset; + int padding = 56 - (offset + 1); + + *p++ = 0x80; + if (padding < 0) { + memset(p, 0x00, padding + sizeof (u64)); + md4_transform_helper(mctx); + p = (char *)mctx->block; + padding = 56; + } + + memset(p, 0, padding); + mctx->block[14] = mctx->byte_count << 3; + mctx->block[15] = mctx->byte_count >> 29; + le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - + sizeof(u64)) / sizeof(u32)); + md4_transform(mctx->hash, mctx->block); + cpu_to_le32_array(mctx->hash, ARRAY_SIZE(mctx->hash)); + memcpy(out, mctx->hash, sizeof(mctx->hash)); + memset(mctx, 0, sizeof(*mctx)); + + return 0; +} + +static struct shash_alg alg = { + .digestsize = MD4_DIGEST_SIZE, + .init = md4_init, + .update = md4_update, + .final = md4_final, + .descsize = sizeof(struct md4_ctx), + .base = { + .cra_name = "md4", + .cra_driver_name = "md4-generic", + .cra_blocksize = MD4_HMAC_BLOCK_SIZE, + .cra_module = THIS_MODULE, + } +}; + +static int __init md4_mod_init(void) +{ + return crypto_register_shash(&alg); +} + +static void __exit md4_mod_fini(void) +{ + crypto_unregister_shash(&alg); +} + +module_init(md4_mod_init); +module_exit(md4_mod_fini); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("MD4 Message Digest Algorithm"); +MODULE_ALIAS_CRYPTO("md4"); -- cgit v1.3.1