From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- crypto/cast6_generic.c | 280 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 280 insertions(+) create mode 100644 crypto/cast6_generic.c (limited to 'crypto/cast6_generic.c') diff --git a/crypto/cast6_generic.c b/crypto/cast6_generic.c new file mode 100644 index 000000000..4c08c4264 --- /dev/null +++ b/crypto/cast6_generic.c @@ -0,0 +1,280 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Kernel cryptographic api. + * cast6.c - Cast6 cipher algorithm [rfc2612]. + * + * CAST-256 (*cast6*) is a DES like Substitution-Permutation Network (SPN) + * cryptosystem built upon the CAST-128 (*cast5*) [rfc2144] encryption + * algorithm. + * + * Copyright (C) 2003 Kartikey Mahendra Bhatt . + */ + + +#include +#include +#include +#include +#include +#include +#include +#include + +#define s1 cast_s1 +#define s2 cast_s2 +#define s3 cast_s3 +#define s4 cast_s4 + +#define F1(D, r, m) ((I = ((m) + (D))), (I = rol32(I, (r))), \ + (((s1[I >> 24] ^ s2[(I>>16)&0xff]) - s3[(I>>8)&0xff]) + s4[I&0xff])) +#define F2(D, r, m) ((I = ((m) ^ (D))), (I = rol32(I, (r))), \ + (((s1[I >> 24] - s2[(I>>16)&0xff]) + s3[(I>>8)&0xff]) ^ s4[I&0xff])) +#define F3(D, r, m) ((I = ((m) - (D))), (I = rol32(I, (r))), \ + (((s1[I >> 24] + s2[(I>>16)&0xff]) ^ s3[(I>>8)&0xff]) - s4[I&0xff])) + +static const u32 Tm[24][8] = { + { 0x5a827999, 0xc95c653a, 0x383650db, 0xa7103c7c, 0x15ea281d, + 0x84c413be, 0xf39dff5f, 0x6277eb00 } , + { 0xd151d6a1, 0x402bc242, 0xaf05ade3, 0x1ddf9984, 0x8cb98525, + 0xfb9370c6, 0x6a6d5c67, 0xd9474808 } , + { 0x482133a9, 0xb6fb1f4a, 0x25d50aeb, 0x94aef68c, 0x0388e22d, + 0x7262cdce, 0xe13cb96f, 0x5016a510 } , + { 0xbef090b1, 0x2dca7c52, 0x9ca467f3, 0x0b7e5394, 0x7a583f35, + 0xe9322ad6, 0x580c1677, 0xc6e60218 } , + { 0x35bfedb9, 0xa499d95a, 0x1373c4fb, 0x824db09c, 0xf1279c3d, + 0x600187de, 0xcedb737f, 0x3db55f20 } , + { 0xac8f4ac1, 0x1b693662, 0x8a432203, 0xf91d0da4, 0x67f6f945, + 0xd6d0e4e6, 0x45aad087, 0xb484bc28 } , + { 0x235ea7c9, 0x9238936a, 0x01127f0b, 0x6fec6aac, 0xdec6564d, + 0x4da041ee, 0xbc7a2d8f, 0x2b541930 } , + { 0x9a2e04d1, 0x0907f072, 0x77e1dc13, 0xe6bbc7b4, 0x5595b355, + 0xc46f9ef6, 0x33498a97, 0xa2237638 } , + { 0x10fd61d9, 0x7fd74d7a, 0xeeb1391b, 0x5d8b24bc, 0xcc65105d, + 0x3b3efbfe, 0xaa18e79f, 0x18f2d340 } , + { 0x87ccbee1, 0xf6a6aa82, 0x65809623, 0xd45a81c4, 0x43346d65, + 0xb20e5906, 0x20e844a7, 0x8fc23048 } , + { 0xfe9c1be9, 0x6d76078a, 0xdc4ff32b, 0x4b29decc, 0xba03ca6d, + 0x28ddb60e, 0x97b7a1af, 0x06918d50 } , + { 0x756b78f1, 0xe4456492, 0x531f5033, 0xc1f93bd4, 0x30d32775, + 0x9fad1316, 0x0e86feb7, 0x7d60ea58 } , + { 0xec3ad5f9, 0x5b14c19a, 0xc9eead3b, 0x38c898dc, 0xa7a2847d, + 0x167c701e, 0x85565bbf, 0xf4304760 } , + { 0x630a3301, 0xd1e41ea2, 0x40be0a43, 0xaf97f5e4, 0x1e71e185, + 0x8d4bcd26, 0xfc25b8c7, 0x6affa468 } , + { 0xd9d99009, 0x48b37baa, 0xb78d674b, 0x266752ec, 0x95413e8d, + 0x041b2a2e, 0x72f515cf, 0xe1cf0170 } , + { 0x50a8ed11, 0xbf82d8b2, 0x2e5cc453, 0x9d36aff4, 0x0c109b95, + 0x7aea8736, 0xe9c472d7, 0x589e5e78 } , + { 0xc7784a19, 0x365235ba, 0xa52c215b, 0x14060cfc, 0x82dff89d, + 0xf1b9e43e, 0x6093cfdf, 0xcf6dbb80 } , + { 0x3e47a721, 0xad2192c2, 0x1bfb7e63, 0x8ad56a04, 0xf9af55a5, + 0x68894146, 0xd7632ce7, 0x463d1888 } , + { 0xb5170429, 0x23f0efca, 0x92cadb6b, 0x01a4c70c, 0x707eb2ad, + 0xdf589e4e, 0x4e3289ef, 0xbd0c7590 } , + { 0x2be66131, 0x9ac04cd2, 0x099a3873, 0x78742414, 0xe74e0fb5, + 0x5627fb56, 0xc501e6f7, 0x33dbd298 } , + { 0xa2b5be39, 0x118fa9da, 0x8069957b, 0xef43811c, 0x5e1d6cbd, + 0xccf7585e, 0x3bd143ff, 0xaaab2fa0 } , + { 0x19851b41, 0x885f06e2, 0xf738f283, 0x6612de24, 0xd4ecc9c5, + 0x43c6b566, 0xb2a0a107, 0x217a8ca8 } , + { 0x90547849, 0xff2e63ea, 0x6e084f8b, 0xdce23b2c, 0x4bbc26cd, + 0xba96126e, 0x296ffe0f, 0x9849e9b0 } , + { 0x0723d551, 0x75fdc0f2, 0xe4d7ac93, 0x53b19834, 0xc28b83d5, + 0x31656f76, 0xa03f5b17, 0x0f1946b8 } +}; + +static const u8 Tr[4][8] = { + { 0x13, 0x04, 0x15, 0x06, 0x17, 0x08, 0x19, 0x0a } , + { 0x1b, 0x0c, 0x1d, 0x0e, 0x1f, 0x10, 0x01, 0x12 } , + { 0x03, 0x14, 0x05, 0x16, 0x07, 0x18, 0x09, 0x1a } , + { 0x0b, 0x1c, 0x0d, 0x1e, 0x0f, 0x00, 0x11, 0x02 } +}; + +/* forward octave */ +static inline void W(u32 *key, unsigned int i) +{ + u32 I; + key[6] ^= F1(key[7], Tr[i % 4][0], Tm[i][0]); + key[5] ^= F2(key[6], Tr[i % 4][1], Tm[i][1]); + key[4] ^= F3(key[5], Tr[i % 4][2], Tm[i][2]); + key[3] ^= F1(key[4], Tr[i % 4][3], Tm[i][3]); + key[2] ^= F2(key[3], Tr[i % 4][4], Tm[i][4]); + key[1] ^= F3(key[2], Tr[i % 4][5], Tm[i][5]); + key[0] ^= F1(key[1], Tr[i % 4][6], Tm[i][6]); + key[7] ^= F2(key[0], Tr[i % 4][7], Tm[i][7]); +} + +int __cast6_setkey(struct cast6_ctx *c, const u8 *in_key, unsigned int key_len) +{ + int i; + u32 key[8]; + __be32 p_key[8]; /* padded key */ + + if (key_len % 4 != 0) + return -EINVAL; + + memset(p_key, 0, 32); + memcpy(p_key, in_key, key_len); + + key[0] = be32_to_cpu(p_key[0]); /* A */ + key[1] = be32_to_cpu(p_key[1]); /* B */ + key[2] = be32_to_cpu(p_key[2]); /* C */ + key[3] = be32_to_cpu(p_key[3]); /* D */ + key[4] = be32_to_cpu(p_key[4]); /* E */ + key[5] = be32_to_cpu(p_key[5]); /* F */ + key[6] = be32_to_cpu(p_key[6]); /* G */ + key[7] = be32_to_cpu(p_key[7]); /* H */ + + for (i = 0; i < 12; i++) { + W(key, 2 * i); + W(key, 2 * i + 1); + + c->Kr[i][0] = key[0] & 0x1f; + c->Kr[i][1] = key[2] & 0x1f; + c->Kr[i][2] = key[4] & 0x1f; + c->Kr[i][3] = key[6] & 0x1f; + + c->Km[i][0] = key[7]; + c->Km[i][1] = key[5]; + c->Km[i][2] = key[3]; + c->Km[i][3] = key[1]; + } + + return 0; +} +EXPORT_SYMBOL_GPL(__cast6_setkey); + +int cast6_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) +{ + return __cast6_setkey(crypto_tfm_ctx(tfm), key, keylen); +} +EXPORT_SYMBOL_GPL(cast6_setkey); + +/*forward quad round*/ +static inline void Q(u32 *block, const u8 *Kr, const u32 *Km) +{ + u32 I; + block[2] ^= F1(block[3], Kr[0], Km[0]); + block[1] ^= F2(block[2], Kr[1], Km[1]); + block[0] ^= F3(block[1], Kr[2], Km[2]); + block[3] ^= F1(block[0], Kr[3], Km[3]); +} + +/*reverse quad round*/ +static inline void QBAR(u32 *block, const u8 *Kr, const u32 *Km) +{ + u32 I; + block[3] ^= F1(block[0], Kr[3], Km[3]); + block[0] ^= F3(block[1], Kr[2], Km[2]); + block[1] ^= F2(block[2], Kr[1], Km[1]); + block[2] ^= F1(block[3], Kr[0], Km[0]); +} + +void __cast6_encrypt(const void *ctx, u8 *outbuf, const u8 *inbuf) +{ + const struct cast6_ctx *c = ctx; + u32 block[4]; + const u32 *Km; + const u8 *Kr; + + block[0] = get_unaligned_be32(inbuf); + block[1] = get_unaligned_be32(inbuf + 4); + block[2] = get_unaligned_be32(inbuf + 8); + block[3] = get_unaligned_be32(inbuf + 12); + + Km = c->Km[0]; Kr = c->Kr[0]; Q(block, Kr, Km); + Km = c->Km[1]; Kr = c->Kr[1]; Q(block, Kr, Km); + Km = c->Km[2]; Kr = c->Kr[2]; Q(block, Kr, Km); + Km = c->Km[3]; Kr = c->Kr[3]; Q(block, Kr, Km); + Km = c->Km[4]; Kr = c->Kr[4]; Q(block, Kr, Km); + Km = c->Km[5]; Kr = c->Kr[5]; Q(block, Kr, Km); + Km = c->Km[6]; Kr = c->Kr[6]; QBAR(block, Kr, Km); + Km = c->Km[7]; Kr = c->Kr[7]; QBAR(block, Kr, Km); + Km = c->Km[8]; Kr = c->Kr[8]; QBAR(block, Kr, Km); + Km = c->Km[9]; Kr = c->Kr[9]; QBAR(block, Kr, Km); + Km = c->Km[10]; Kr = c->Kr[10]; QBAR(block, Kr, Km); + Km = c->Km[11]; Kr = c->Kr[11]; QBAR(block, Kr, Km); + + put_unaligned_be32(block[0], outbuf); + put_unaligned_be32(block[1], outbuf + 4); + put_unaligned_be32(block[2], outbuf + 8); + put_unaligned_be32(block[3], outbuf + 12); +} +EXPORT_SYMBOL_GPL(__cast6_encrypt); + +static void cast6_encrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf) +{ + __cast6_encrypt(crypto_tfm_ctx(tfm), outbuf, inbuf); +} + +void __cast6_decrypt(const void *ctx, u8 *outbuf, const u8 *inbuf) +{ + const struct cast6_ctx *c = ctx; + u32 block[4]; + const u32 *Km; + const u8 *Kr; + + block[0] = get_unaligned_be32(inbuf); + block[1] = get_unaligned_be32(inbuf + 4); + block[2] = get_unaligned_be32(inbuf + 8); + block[3] = get_unaligned_be32(inbuf + 12); + + Km = c->Km[11]; Kr = c->Kr[11]; Q(block, Kr, Km); + Km = c->Km[10]; Kr = c->Kr[10]; Q(block, Kr, Km); + Km = c->Km[9]; Kr = c->Kr[9]; Q(block, Kr, Km); + Km = c->Km[8]; Kr = c->Kr[8]; Q(block, Kr, Km); + Km = c->Km[7]; Kr = c->Kr[7]; Q(block, Kr, Km); + Km = c->Km[6]; Kr = c->Kr[6]; Q(block, Kr, Km); + Km = c->Km[5]; Kr = c->Kr[5]; QBAR(block, Kr, Km); + Km = c->Km[4]; Kr = c->Kr[4]; QBAR(block, Kr, Km); + Km = c->Km[3]; Kr = c->Kr[3]; QBAR(block, Kr, Km); + Km = c->Km[2]; Kr = c->Kr[2]; QBAR(block, Kr, Km); + Km = c->Km[1]; Kr = c->Kr[1]; QBAR(block, Kr, Km); + Km = c->Km[0]; Kr = c->Kr[0]; QBAR(block, Kr, Km); + + put_unaligned_be32(block[0], outbuf); + put_unaligned_be32(block[1], outbuf + 4); + put_unaligned_be32(block[2], outbuf + 8); + put_unaligned_be32(block[3], outbuf + 12); +} +EXPORT_SYMBOL_GPL(__cast6_decrypt); + +static void cast6_decrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf) +{ + __cast6_decrypt(crypto_tfm_ctx(tfm), outbuf, inbuf); +} + +static struct crypto_alg alg = { + .cra_name = "cast6", + .cra_driver_name = "cast6-generic", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = CAST6_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct cast6_ctx), + .cra_module = THIS_MODULE, + .cra_u = { + .cipher = { + .cia_min_keysize = CAST6_MIN_KEY_SIZE, + .cia_max_keysize = CAST6_MAX_KEY_SIZE, + .cia_setkey = cast6_setkey, + .cia_encrypt = cast6_encrypt, + .cia_decrypt = cast6_decrypt} + } +}; + +static int __init cast6_mod_init(void) +{ + return crypto_register_alg(&alg); +} + +static void __exit cast6_mod_fini(void) +{ + crypto_unregister_alg(&alg); +} + +module_init(cast6_mod_init); +module_exit(cast6_mod_fini); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Cast6 Cipher Algorithm"); +MODULE_ALIAS_CRYPTO("cast6"); +MODULE_ALIAS_CRYPTO("cast6-generic"); -- cgit v1.3.1