From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- crypto/blkcipher.c | 559 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 559 insertions(+) create mode 100644 crypto/blkcipher.c (limited to 'crypto/blkcipher.c') diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c new file mode 100644 index 000000000..f93abf13b --- /dev/null +++ b/crypto/blkcipher.c @@ -0,0 +1,559 @@ +/* + * Block chaining cipher operations. + * + * Generic encrypt/decrypt wrapper for ciphers, handles operations across + * multiple page boundaries by using temporary blocks. In user context, + * the kernel is given a chance to schedule us once per page. + * + * Copyright (c) 2006 Herbert Xu + * + * 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 +#include +#include +#include +#include +#include + +#include "internal.h" + +enum { + BLKCIPHER_WALK_PHYS = 1 << 0, + BLKCIPHER_WALK_SLOW = 1 << 1, + BLKCIPHER_WALK_COPY = 1 << 2, + BLKCIPHER_WALK_DIFF = 1 << 3, +}; + +static int blkcipher_walk_next(struct blkcipher_desc *desc, + struct blkcipher_walk *walk); +static int blkcipher_walk_first(struct blkcipher_desc *desc, + struct blkcipher_walk *walk); + +static inline void blkcipher_map_src(struct blkcipher_walk *walk) +{ + walk->src.virt.addr = scatterwalk_map(&walk->in); +} + +static inline void blkcipher_map_dst(struct blkcipher_walk *walk) +{ + walk->dst.virt.addr = scatterwalk_map(&walk->out); +} + +static inline void blkcipher_unmap_src(struct blkcipher_walk *walk) +{ + scatterwalk_unmap(walk->src.virt.addr); +} + +static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk) +{ + scatterwalk_unmap(walk->dst.virt.addr); +} + +/* Get a spot of the specified length that does not straddle a page. + * The caller needs to ensure that there is enough space for this operation. + */ +static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len) +{ + u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); + return max(start, end_page); +} + +static inline void blkcipher_done_slow(struct blkcipher_walk *walk, + unsigned int bsize) +{ + u8 *addr; + + addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1); + addr = blkcipher_get_spot(addr, bsize); + scatterwalk_copychunks(addr, &walk->out, bsize, 1); +} + +static inline void blkcipher_done_fast(struct blkcipher_walk *walk, + unsigned int n) +{ + if (walk->flags & BLKCIPHER_WALK_COPY) { + blkcipher_map_dst(walk); + memcpy(walk->dst.virt.addr, walk->page, n); + blkcipher_unmap_dst(walk); + } else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) { + if (walk->flags & BLKCIPHER_WALK_DIFF) + blkcipher_unmap_dst(walk); + blkcipher_unmap_src(walk); + } + + scatterwalk_advance(&walk->in, n); + scatterwalk_advance(&walk->out, n); +} + +int blkcipher_walk_done(struct blkcipher_desc *desc, + struct blkcipher_walk *walk, int err) +{ + unsigned int n; /* bytes processed */ + bool more; + + if (unlikely(err < 0)) + goto finish; + + n = walk->nbytes - err; + walk->total -= n; + more = (walk->total != 0); + + if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW))) { + blkcipher_done_fast(walk, n); + } else { + if (WARN_ON(err)) { + /* unexpected case; didn't process all bytes */ + err = -EINVAL; + goto finish; + } + blkcipher_done_slow(walk, n); + } + + scatterwalk_done(&walk->in, 0, more); + scatterwalk_done(&walk->out, 1, more); + + if (more) { + crypto_yield(desc->flags); + return blkcipher_walk_next(desc, walk); + } + err = 0; +finish: + walk->nbytes = 0; + if (walk->iv != desc->info) + memcpy(desc->info, walk->iv, walk->ivsize); + if (walk->buffer != walk->page) + kfree(walk->buffer); + if (walk->page) + free_page((unsigned long)walk->page); + return err; +} +EXPORT_SYMBOL_GPL(blkcipher_walk_done); + +static inline int blkcipher_next_slow(struct blkcipher_desc *desc, + struct blkcipher_walk *walk, + unsigned int bsize, + unsigned int alignmask) +{ + unsigned int n; + unsigned aligned_bsize = ALIGN(bsize, alignmask + 1); + + if (walk->buffer) + goto ok; + + walk->buffer = walk->page; + if (walk->buffer) + goto ok; + + n = aligned_bsize * 3 - (alignmask + 1) + + (alignmask & ~(crypto_tfm_ctx_alignment() - 1)); + walk->buffer = kmalloc(n, GFP_ATOMIC); + if (!walk->buffer) + return blkcipher_walk_done(desc, walk, -ENOMEM); + +ok: + walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer, + alignmask + 1); + walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize); + walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr + + aligned_bsize, bsize); + + scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0); + + walk->nbytes = bsize; + walk->flags |= BLKCIPHER_WALK_SLOW; + + return 0; +} + +static inline int blkcipher_next_copy(struct blkcipher_walk *walk) +{ + u8 *tmp = walk->page; + + blkcipher_map_src(walk); + memcpy(tmp, walk->src.virt.addr, walk->nbytes); + blkcipher_unmap_src(walk); + + walk->src.virt.addr = tmp; + walk->dst.virt.addr = tmp; + + return 0; +} + +static inline int blkcipher_next_fast(struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + unsigned long diff; + + walk->src.phys.page = scatterwalk_page(&walk->in); + walk->src.phys.offset = offset_in_page(walk->in.offset); + walk->dst.phys.page = scatterwalk_page(&walk->out); + walk->dst.phys.offset = offset_in_page(walk->out.offset); + + if (walk->flags & BLKCIPHER_WALK_PHYS) + return 0; + + diff = walk->src.phys.offset - walk->dst.phys.offset; + diff |= walk->src.virt.page - walk->dst.virt.page; + + blkcipher_map_src(walk); + walk->dst.virt.addr = walk->src.virt.addr; + + if (diff) { + walk->flags |= BLKCIPHER_WALK_DIFF; + blkcipher_map_dst(walk); + } + + return 0; +} + +static int blkcipher_walk_next(struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + unsigned int bsize; + unsigned int n; + int err; + + n = walk->total; + if (unlikely(n < walk->cipher_blocksize)) { + desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; + return blkcipher_walk_done(desc, walk, -EINVAL); + } + + bsize = min(walk->walk_blocksize, n); + + walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY | + BLKCIPHER_WALK_DIFF); + if (!scatterwalk_aligned(&walk->in, walk->alignmask) || + !scatterwalk_aligned(&walk->out, walk->alignmask)) { + walk->flags |= BLKCIPHER_WALK_COPY; + if (!walk->page) { + walk->page = (void *)__get_free_page(GFP_ATOMIC); + if (!walk->page) + n = 0; + } + } + + n = scatterwalk_clamp(&walk->in, n); + n = scatterwalk_clamp(&walk->out, n); + + if (unlikely(n < bsize)) { + err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask); + goto set_phys_lowmem; + } + + walk->nbytes = n; + if (walk->flags & BLKCIPHER_WALK_COPY) { + err = blkcipher_next_copy(walk); + goto set_phys_lowmem; + } + + return blkcipher_next_fast(desc, walk); + +set_phys_lowmem: + if (walk->flags & BLKCIPHER_WALK_PHYS) { + walk->src.phys.page = virt_to_page(walk->src.virt.addr); + walk->dst.phys.page = virt_to_page(walk->dst.virt.addr); + walk->src.phys.offset &= PAGE_SIZE - 1; + walk->dst.phys.offset &= PAGE_SIZE - 1; + } + return err; +} + +static inline int blkcipher_copy_iv(struct blkcipher_walk *walk) +{ + unsigned bs = walk->walk_blocksize; + unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1); + unsigned int size = aligned_bs * 2 + + walk->ivsize + max(aligned_bs, walk->ivsize) - + (walk->alignmask + 1); + u8 *iv; + + size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1); + walk->buffer = kmalloc(size, GFP_ATOMIC); + if (!walk->buffer) + return -ENOMEM; + + iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1); + iv = blkcipher_get_spot(iv, bs) + aligned_bs; + iv = blkcipher_get_spot(iv, bs) + aligned_bs; + iv = blkcipher_get_spot(iv, walk->ivsize); + + walk->iv = memcpy(iv, walk->iv, walk->ivsize); + return 0; +} + +int blkcipher_walk_virt(struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + walk->flags &= ~BLKCIPHER_WALK_PHYS; + walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm); + walk->cipher_blocksize = walk->walk_blocksize; + walk->ivsize = crypto_blkcipher_ivsize(desc->tfm); + walk->alignmask = crypto_blkcipher_alignmask(desc->tfm); + return blkcipher_walk_first(desc, walk); +} +EXPORT_SYMBOL_GPL(blkcipher_walk_virt); + +int blkcipher_walk_phys(struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + walk->flags |= BLKCIPHER_WALK_PHYS; + walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm); + walk->cipher_blocksize = walk->walk_blocksize; + walk->ivsize = crypto_blkcipher_ivsize(desc->tfm); + walk->alignmask = crypto_blkcipher_alignmask(desc->tfm); + return blkcipher_walk_first(desc, walk); +} +EXPORT_SYMBOL_GPL(blkcipher_walk_phys); + +static int blkcipher_walk_first(struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + if (WARN_ON_ONCE(in_irq())) + return -EDEADLK; + + walk->iv = desc->info; + walk->nbytes = walk->total; + if (unlikely(!walk->total)) + return 0; + + walk->buffer = NULL; + if (unlikely(((unsigned long)walk->iv & walk->alignmask))) { + int err = blkcipher_copy_iv(walk); + if (err) + return err; + } + + scatterwalk_start(&walk->in, walk->in.sg); + scatterwalk_start(&walk->out, walk->out.sg); + walk->page = NULL; + + return blkcipher_walk_next(desc, walk); +} + +int blkcipher_walk_virt_block(struct blkcipher_desc *desc, + struct blkcipher_walk *walk, + unsigned int blocksize) +{ + walk->flags &= ~BLKCIPHER_WALK_PHYS; + walk->walk_blocksize = blocksize; + walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm); + walk->ivsize = crypto_blkcipher_ivsize(desc->tfm); + walk->alignmask = crypto_blkcipher_alignmask(desc->tfm); + return blkcipher_walk_first(desc, walk); +} +EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block); + +int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc, + struct blkcipher_walk *walk, + struct crypto_aead *tfm, + unsigned int blocksize) +{ + walk->flags &= ~BLKCIPHER_WALK_PHYS; + walk->walk_blocksize = blocksize; + walk->cipher_blocksize = crypto_aead_blocksize(tfm); + walk->ivsize = crypto_aead_ivsize(tfm); + walk->alignmask = crypto_aead_alignmask(tfm); + return blkcipher_walk_first(desc, walk); +} +EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block); + +static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key, + unsigned int keylen) +{ + struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher; + unsigned long alignmask = crypto_tfm_alg_alignmask(tfm); + int ret; + u8 *buffer, *alignbuffer; + unsigned long absize; + + absize = keylen + alignmask; + buffer = kmalloc(absize, GFP_ATOMIC); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + ret = cipher->setkey(tfm, alignbuffer, keylen); + memset(alignbuffer, 0, keylen); + kfree(buffer); + return ret; +} + +static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) +{ + struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher; + unsigned long alignmask = crypto_tfm_alg_alignmask(tfm); + + if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) { + tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; + return -EINVAL; + } + + if ((unsigned long)key & alignmask) + return setkey_unaligned(tfm, key, keylen); + + return cipher->setkey(tfm, key, keylen); +} + +static int async_setkey(struct crypto_ablkcipher *tfm, const u8 *key, + unsigned int keylen) +{ + return setkey(crypto_ablkcipher_tfm(tfm), key, keylen); +} + +static int async_encrypt(struct ablkcipher_request *req) +{ + struct crypto_tfm *tfm = req->base.tfm; + struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; + struct blkcipher_desc desc = { + .tfm = __crypto_blkcipher_cast(tfm), + .info = req->info, + .flags = req->base.flags, + }; + + + return alg->encrypt(&desc, req->dst, req->src, req->nbytes); +} + +static int async_decrypt(struct ablkcipher_request *req) +{ + struct crypto_tfm *tfm = req->base.tfm; + struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; + struct blkcipher_desc desc = { + .tfm = __crypto_blkcipher_cast(tfm), + .info = req->info, + .flags = req->base.flags, + }; + + return alg->decrypt(&desc, req->dst, req->src, req->nbytes); +} + +static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type, + u32 mask) +{ + struct blkcipher_alg *cipher = &alg->cra_blkcipher; + unsigned int len = alg->cra_ctxsize; + + if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK && + cipher->ivsize) { + len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1); + len += cipher->ivsize; + } + + return len; +} + +static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm) +{ + struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher; + struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; + + crt->setkey = async_setkey; + crt->encrypt = async_encrypt; + crt->decrypt = async_decrypt; + crt->base = __crypto_ablkcipher_cast(tfm); + crt->ivsize = alg->ivsize; + + return 0; +} + +static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm) +{ + struct blkcipher_tfm *crt = &tfm->crt_blkcipher; + struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; + unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1; + unsigned long addr; + + crt->setkey = setkey; + crt->encrypt = alg->encrypt; + crt->decrypt = alg->decrypt; + + addr = (unsigned long)crypto_tfm_ctx(tfm); + addr = ALIGN(addr, align); + addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align); + crt->iv = (void *)addr; + + return 0; +} + +static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask) +{ + struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; + + if (alg->ivsize > PAGE_SIZE / 8) + return -EINVAL; + + if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK) + return crypto_init_blkcipher_ops_sync(tfm); + else + return crypto_init_blkcipher_ops_async(tfm); +} + +#ifdef CONFIG_NET +static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + struct crypto_report_blkcipher rblkcipher; + + strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type)); + strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "", + sizeof(rblkcipher.geniv)); + rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; + + rblkcipher.blocksize = alg->cra_blocksize; + rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize; + rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize; + rblkcipher.ivsize = alg->cra_blkcipher.ivsize; + + if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, + sizeof(struct crypto_report_blkcipher), &rblkcipher)) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -EMSGSIZE; +} +#else +static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + return -ENOSYS; +} +#endif + +static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg) + __maybe_unused; +static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg) +{ + seq_printf(m, "type : blkcipher\n"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize); + seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize); + seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize); + seq_printf(m, "geniv : %s\n", alg->cra_blkcipher.geniv ?: + ""); +} + +const struct crypto_type crypto_blkcipher_type = { + .ctxsize = crypto_blkcipher_ctxsize, + .init = crypto_init_blkcipher_ops, +#ifdef CONFIG_PROC_FS + .show = crypto_blkcipher_show, +#endif + .report = crypto_blkcipher_report, +}; +EXPORT_SYMBOL_GPL(crypto_blkcipher_type); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Generic block chaining cipher type"); -- cgit v1.2.3