// SPDX-License-Identifier: GPL-2.0-or-later /* * Symmetric key 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) 2015 Herbert Xu <herbert@gondor.apana.org.au> */ #include <crypto/internal/aead.h> #include <crypto/internal/skcipher.h> #include <crypto/scatterwalk.h> #include <linux/bug.h> #include <linux/cryptouser.h> #include <linux/compiler.h> #include <linux/list.h> #include <linux/module.h> #include <linux/rtnetlink.h> #include <linux/seq_file.h> #include <net/netlink.h> #include "internal.h" enum { SKCIPHER_WALK_PHYS = 1 << 0, SKCIPHER_WALK_SLOW = 1 << 1, SKCIPHER_WALK_COPY = 1 << 2, SKCIPHER_WALK_DIFF = 1 << 3, SKCIPHER_WALK_SLEEP = 1 << 4, }; struct skcipher_walk_buffer { struct list_head entry; struct scatter_walk dst; unsigned int len; u8 *data; u8 buffer[]; }; static int skcipher_walk_next(struct skcipher_walk *walk); static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr) { if (PageHighMem(scatterwalk_page(walk))) kunmap_atomic(vaddr); } static inline void *skcipher_map(struct scatter_walk *walk) { struct page *page = scatterwalk_page(walk); return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) + offset_in_page(walk->offset); } static inline void skcipher_map_src(struct skcipher_walk *walk) { walk->src.virt.addr = skcipher_map(&walk->in); } static inline void skcipher_map_dst(struct skcipher_walk *walk) { walk->dst.virt.addr = skcipher_map(&walk->out); } static inline void skcipher_unmap_src(struct skcipher_walk *walk) { skcipher_unmap(&walk->in, walk->src.virt.addr); } static inline void skcipher_unmap_dst(struct skcipher_walk *walk) { skcipher_unmap(&walk->out, walk->dst.virt.addr); } static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk) { return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC; } /* 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 *skcipher_get_spot(u8 *start, unsigned int len) { u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); return max(start, end_page); } static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize) { u8 *addr; addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1); addr = skcipher_get_spot(addr, bsize); scatterwalk_copychunks(addr, &walk->out, bsize, (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1); return 0; } int skcipher_walk_done(struct skcipher_walk *walk, int err) { unsigned int n = walk->nbytes; unsigned int nbytes = 0; if (!n) goto finish; if (likely(err >= 0)) { n -= err; nbytes = walk->total - n; } if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS | SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY | SKCIPHER_WALK_DIFF)))) { unmap_src: skcipher_unmap_src(walk); } else if (walk->flags & SKCIPHER_WALK_DIFF) { skcipher_unmap_dst(walk); goto unmap_src; } else if (walk->flags & SKCIPHER_WALK_COPY) { skcipher_map_dst(walk); memcpy(walk->dst.virt.addr, walk->page, n); skcipher_unmap_dst(walk); } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) { if (err > 0) { /* * Didn't process all bytes. Either the algorithm is * broken, or this was the last step and it turned out * the message wasn't evenly divisible into blocks but * the algorithm requires it. */ err = -EINVAL; nbytes = 0; } else n = skcipher_done_slow(walk, n); } if (err > 0) err = 0; walk->total = nbytes; walk->nbytes = 0; scatterwalk_advance(&walk->in, n); scatterwalk_advance(&walk->out, n); scatterwalk_done(&walk->in, 0, nbytes); scatterwalk_done(&walk->out, 1, nbytes); if (nbytes) { crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ? CRYPTO_TFM_REQ_MAY_SLEEP : 0); return skcipher_walk_next(walk); } finish: /* Short-circuit for the common/fast path. */ if (!((unsigned long)walk->buffer | (unsigned long)walk->page)) goto out; if (walk->flags & SKCIPHER_WALK_PHYS) goto out; if (walk->iv != walk->oiv) memcpy(walk->oiv, walk->iv, walk->ivsize); if (walk->buffer != walk->page) kfree(walk->buffer); if (walk->page) free_page((unsigned long)walk->page); out: return err; } EXPORT_SYMBOL_GPL(skcipher_walk_done); void skcipher_walk_complete(struct skcipher_walk *walk, int err) { struct skcipher_walk_buffer *p, *tmp; list_for_each_entry_safe(p, tmp, &walk->buffers, entry) { u8 *data; if (err) goto done; data = p->data; if (!data) { data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1); data = skcipher_get_spot(data, walk->stride); } scatterwalk_copychunks(data, &p->dst, p->len, 1); if (offset_in_page(p->data) + p->len + walk->stride > PAGE_SIZE) free_page((unsigned long)p->data); done: list_del(&p->entry); kfree(p); } if (!err && walk->iv != walk->oiv) memcpy(walk->oiv, walk->iv, walk->ivsize); if (walk->buffer != walk->page) kfree(walk->buffer); if (walk->page) free_page((unsigned long)walk->page); } EXPORT_SYMBOL_GPL(skcipher_walk_complete); static void skcipher_queue_write(struct skcipher_walk *walk, struct skcipher_walk_buffer *p) { p->dst = walk->out; list_add_tail(&p->entry, &walk->buffers); } static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize) { bool phys = walk->flags & SKCIPHER_WALK_PHYS; unsigned alignmask = walk->alignmask; struct skcipher_walk_buffer *p; unsigned a; unsigned n; u8 *buffer; void *v; if (!phys) { if (!walk->buffer) walk->buffer = walk->page; buffer = walk->buffer; if (buffer) goto ok; } /* Start with the minimum alignment of kmalloc. */ a = crypto_tfm_ctx_alignment() - 1; n = bsize; if (phys) { /* Calculate the minimum alignment of p->buffer. */ a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1; n += sizeof(*p); } /* Minimum size to align p->buffer by alignmask. */ n += alignmask & ~a; /* Minimum size to ensure p->buffer does not straddle a page. */ n += (bsize - 1) & ~(alignmask | a); v = kzalloc(n, skcipher_walk_gfp(walk)); if (!v) return skcipher_walk_done(walk, -ENOMEM); if (phys) { p = v; p->len = bsize; skcipher_queue_write(walk, p); buffer = p->buffer; } else { walk->buffer = v; buffer = v; } ok: walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1); walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize); walk->src.virt.addr = walk->dst.virt.addr; scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0); walk->nbytes = bsize; walk->flags |= SKCIPHER_WALK_SLOW; return 0; } static int skcipher_next_copy(struct skcipher_walk *walk) { struct skcipher_walk_buffer *p; u8 *tmp = walk->page; skcipher_map_src(walk); memcpy(tmp, walk->src.virt.addr, walk->nbytes); skcipher_unmap_src(walk); walk->src.virt.addr = tmp; walk->dst.virt.addr = tmp; if (!(walk->flags & SKCIPHER_WALK_PHYS)) return 0; p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk)); if (!p) return -ENOMEM; p->data = walk->page; p->len = walk->nbytes; skcipher_queue_write(walk, p); if (offset_in_page(walk->page) + walk->nbytes + walk->stride > PAGE_SIZE) walk->page = NULL; else walk->page += walk->nbytes; return 0; } static int skcipher_next_fast(struct skcipher_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 & SKCIPHER_WALK_PHYS) return 0; diff = walk->src.phys.offset - walk->dst.phys.offset; diff |= walk->src.virt.page - walk->dst.virt.page; skcipher_map_src(walk); walk->dst.virt.addr = walk->src.virt.addr; if (diff) { walk->flags |= SKCIPHER_WALK_DIFF; skcipher_map_dst(walk); } return 0; } static int skcipher_walk_next(struct skcipher_walk *walk) { unsigned int bsize; unsigned int n; int err; walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY | SKCIPHER_WALK_DIFF); n = walk->total; bsize = min(walk->stride, max(n, walk->blocksize)); n = scatterwalk_clamp(&walk->in, n); n = scatterwalk_clamp(&walk->out, n); if (unlikely(n < bsize)) { if (unlikely(walk->total < walk->blocksize)) return skcipher_walk_done(walk, -EINVAL); slow_path: err = skcipher_next_slow(walk, bsize); goto set_phys_lowmem; } if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) { if (!walk->page) { gfp_t gfp = skcipher_walk_gfp(walk); walk->page = (void *)__get_free_page(gfp); if (!walk->page) goto slow_path; } walk->nbytes = min_t(unsigned, n, PAGE_SIZE - offset_in_page(walk->page)); walk->flags |= SKCIPHER_WALK_COPY; err = skcipher_next_copy(walk); goto set_phys_lowmem; } walk->nbytes = n; return skcipher_next_fast(walk); set_phys_lowmem: if (!err && (walk->flags & SKCIPHER_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 int skcipher_copy_iv(struct skcipher_walk *walk) { unsigned a = crypto_tfm_ctx_alignment() - 1; unsigned alignmask = walk->alignmask; unsigned ivsize = walk->ivsize; unsigned bs = walk->stride; unsigned aligned_bs; unsigned size; u8 *iv; aligned_bs = ALIGN(bs, alignmask + 1); /* Minimum size to align buffer by alignmask. */ size = alignmask & ~a; if (walk->flags & SKCIPHER_WALK_PHYS) size += ivsize; else { size += aligned_bs + ivsize; /* Minimum size to ensure buffer does not straddle a page. */ size += (bs - 1) & ~(alignmask | a); } walk->buffer = kmalloc(size, skcipher_walk_gfp(walk)); if (!walk->buffer) return -ENOMEM; iv = PTR_ALIGN(walk->buffer, alignmask + 1); iv = skcipher_get_spot(iv, bs) + aligned_bs; walk->iv = memcpy(iv, walk->iv, walk->ivsize); return 0; } static int skcipher_walk_first(struct skcipher_walk *walk) { if (WARN_ON_ONCE(in_irq())) return -EDEADLK; walk->buffer = NULL; if (unlikely(((unsigned long)walk->iv & walk->alignmask))) { int err = skcipher_copy_iv(walk); if (err) return err; } walk->page = NULL; return skcipher_walk_next(walk); } static int skcipher_walk_skcipher(struct skcipher_walk *walk, struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); walk->total = req->cryptlen; walk->nbytes = 0; walk->iv = req->iv; walk->oiv = req->iv; if (unlikely(!walk->total)) return 0; scatterwalk_start(&walk->in, req->src); scatterwalk_start(&walk->out, req->dst); walk->flags &= ~SKCIPHER_WALK_SLEEP; walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? SKCIPHER_WALK_SLEEP : 0; walk->blocksize = crypto_skcipher_blocksize(tfm); walk->stride = crypto_skcipher_walksize(tfm); walk->ivsize = crypto_skcipher_ivsize(tfm); walk->alignmask = crypto_skcipher_alignmask(tfm); return skcipher_walk_first(walk); } int skcipher_walk_virt(struct skcipher_walk *walk, struct skcipher_request *req, bool atomic) { int err; might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); walk->flags &= ~SKCIPHER_WALK_PHYS; err = skcipher_walk_skcipher(walk, req); walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0; return err; } EXPORT_SYMBOL_GPL(skcipher_walk_virt); void skcipher_walk_atomise(struct skcipher_walk *walk) { walk->flags &= ~SKCIPHER_WALK_SLEEP; } EXPORT_SYMBOL_GPL(skcipher_walk_atomise); int skcipher_walk_async(struct skcipher_walk *walk, struct skcipher_request *req) { walk->flags |= SKCIPHER_WALK_PHYS; INIT_LIST_HEAD(&walk->buffers); return skcipher_walk_skcipher(walk, req); } EXPORT_SYMBOL_GPL(skcipher_walk_async); static int skcipher_walk_aead_common(struct skcipher_walk *walk, struct aead_request *req, bool atomic) { struct crypto_aead *tfm = crypto_aead_reqtfm(req); int err; walk->nbytes = 0; walk->iv = req->iv; walk->oiv = req->iv; if (unlikely(!walk->total)) return 0; walk->flags &= ~SKCIPHER_WALK_PHYS; scatterwalk_start(&walk->in, req->src); scatterwalk_start(&walk->out, req->dst); scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2); scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2); scatterwalk_done(&walk->in, 0, walk->total); scatterwalk_done(&walk->out, 0, walk->total); if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) walk->flags |= SKCIPHER_WALK_SLEEP; else walk->flags &= ~SKCIPHER_WALK_SLEEP; walk->blocksize = crypto_aead_blocksize(tfm); walk->stride = crypto_aead_chunksize(tfm); walk->ivsize = crypto_aead_ivsize(tfm); walk->alignmask = crypto_aead_alignmask(tfm); err = skcipher_walk_first(walk); if (atomic) walk->flags &= ~SKCIPHER_WALK_SLEEP; return err; } int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req, bool atomic) { walk->total = req->cryptlen; return skcipher_walk_aead_common(walk, req, atomic); } EXPORT_SYMBOL_GPL(skcipher_walk_aead); int skcipher_walk_aead_encrypt(struct skcipher_walk *walk, struct aead_request *req, bool atomic) { walk->total = req->cryptlen; return skcipher_walk_aead_common(walk, req, atomic); } EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt); int skcipher_walk_aead_decrypt(struct skcipher_walk *walk, struct aead_request *req, bool atomic) { struct crypto_aead *tfm = crypto_aead_reqtfm(req); walk->total = req->cryptlen - crypto_aead_authsize(tfm); return skcipher_walk_aead_common(walk, req, atomic); } EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt); static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg) { return crypto_alg_extsize(alg); } static void skcipher_set_needkey(struct crypto_skcipher *tfm) { if (tfm->keysize) crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY); } static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm, const u8 *key, unsigned int keylen) { unsigned long alignmask = crypto_skcipher_alignmask(tfm); struct skcipher_alg *cipher = crypto_skcipher_alg(tfm); u8 *buffer, *alignbuffer; unsigned long absize; int ret; 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); kzfree(buffer); return ret; } static int skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key, unsigned int keylen) { struct skcipher_alg *cipher = crypto_skcipher_alg(tfm); unsigned long alignmask = crypto_skcipher_alignmask(tfm); int err; if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) { crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); return -EINVAL; } if ((unsigned long)key & alignmask) err = skcipher_setkey_unaligned(tfm, key, keylen); else err = cipher->setkey(tfm, key, keylen); if (unlikely(err)) { skcipher_set_needkey(tfm); return err; } crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); return 0; } int crypto_skcipher_encrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_alg *alg = tfm->base.__crt_alg; unsigned int cryptlen = req->cryptlen; int ret; crypto_stats_get(alg); if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY; else ret = tfm->encrypt(req); crypto_stats_skcipher_encrypt(cryptlen, ret, alg); return ret; } EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt); int crypto_skcipher_decrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_alg *alg = tfm->base.__crt_alg; unsigned int cryptlen = req->cryptlen; int ret; crypto_stats_get(alg); if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY; else ret = tfm->decrypt(req); crypto_stats_skcipher_decrypt(cryptlen, ret, alg); return ret; } EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt); static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm) { struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); alg->exit(skcipher); } static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm) { struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); skcipher->setkey = skcipher_setkey; skcipher->encrypt = alg->encrypt; skcipher->decrypt = alg->decrypt; skcipher->ivsize = alg->ivsize; skcipher->keysize = alg->max_keysize; skcipher_set_needkey(skcipher); if (alg->exit) skcipher->base.exit = crypto_skcipher_exit_tfm; if (alg->init) return alg->init(skcipher); return 0; } static void crypto_skcipher_free_instance(struct crypto_instance *inst) { struct skcipher_instance *skcipher = container_of(inst, struct skcipher_instance, s.base); skcipher->free(skcipher); } static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) __maybe_unused; static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) { struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg, base); seq_printf(m, "type : skcipher\n"); seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no"); seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); seq_printf(m, "min keysize : %u\n", skcipher->min_keysize); seq_printf(m, "max keysize : %u\n", skcipher->max_keysize); seq_printf(m, "ivsize : %u\n", skcipher->ivsize); seq_printf(m, "chunksize : %u\n", skcipher->chunksize); seq_printf(m, "walksize : %u\n", skcipher->walksize); } #ifdef CONFIG_NET static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg) { struct crypto_report_blkcipher rblkcipher; struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg, base); memset(&rblkcipher, 0, sizeof(rblkcipher)); strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type)); strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv)); rblkcipher.blocksize = alg->cra_blocksize; rblkcipher.min_keysize = skcipher->min_keysize; rblkcipher.max_keysize = skcipher->max_keysize; rblkcipher.ivsize = skcipher->ivsize; return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, sizeof(rblkcipher), &rblkcipher); } #else static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg) { return -ENOSYS; } #endif static const struct crypto_type crypto_skcipher_type = { .extsize = crypto_skcipher_extsize, .init_tfm = crypto_skcipher_init_tfm, .free = crypto_skcipher_free_instance, #ifdef CONFIG_PROC_FS .show = crypto_skcipher_show, #endif .report = crypto_skcipher_report, .maskclear = ~CRYPTO_ALG_TYPE_MASK, .maskset = CRYPTO_ALG_TYPE_MASK, .type = CRYPTO_ALG_TYPE_SKCIPHER, .tfmsize = offsetof(struct crypto_skcipher, base), }; int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name, u32 type, u32 mask) { spawn->base.frontend = &crypto_skcipher_type; return crypto_grab_spawn(&spawn->base, name, type, mask); } EXPORT_SYMBOL_GPL(crypto_grab_skcipher); struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name, u32 type, u32 mask) { return crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask); } EXPORT_SYMBOL_GPL(crypto_alloc_skcipher); struct crypto_sync_skcipher *crypto_alloc_sync_skcipher( const char *alg_name, u32 type, u32 mask) { struct crypto_skcipher *tfm; /* Only sync algorithms allowed. */ mask |= CRYPTO_ALG_ASYNC; tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask); /* * Make sure we do not allocate something that might get used with * an on-stack request: check the request size. */ if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) > MAX_SYNC_SKCIPHER_REQSIZE)) { crypto_free_skcipher(tfm); return ERR_PTR(-EINVAL); } return (struct crypto_sync_skcipher *)tfm; } EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher); int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask) { return crypto_type_has_alg(alg_name, &crypto_skcipher_type, type, mask); } EXPORT_SYMBOL_GPL(crypto_has_skcipher); static int skcipher_prepare_alg(struct skcipher_alg *alg) { struct crypto_alg *base = &alg->base; if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 || alg->walksize > PAGE_SIZE / 8) return -EINVAL; if (!alg->chunksize) alg->chunksize = base->cra_blocksize; if (!alg->walksize) alg->walksize = alg->chunksize; base->cra_type = &crypto_skcipher_type; base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER; return 0; } int crypto_register_skcipher(struct skcipher_alg *alg) { struct crypto_alg *base = &alg->base; int err; err = skcipher_prepare_alg(alg); if (err) return err; return crypto_register_alg(base); } EXPORT_SYMBOL_GPL(crypto_register_skcipher); void crypto_unregister_skcipher(struct skcipher_alg *alg) { crypto_unregister_alg(&alg->base); } EXPORT_SYMBOL_GPL(crypto_unregister_skcipher); int crypto_register_skciphers(struct skcipher_alg *algs, int count) { int i, ret; for (i = 0; i < count; i++) { ret = crypto_register_skcipher(&algs[i]); if (ret) goto err; } return 0; err: for (--i; i >= 0; --i) crypto_unregister_skcipher(&algs[i]); return ret; } EXPORT_SYMBOL_GPL(crypto_register_skciphers); void crypto_unregister_skciphers(struct skcipher_alg *algs, int count) { int i; for (i = count - 1; i >= 0; --i) crypto_unregister_skcipher(&algs[i]); } EXPORT_SYMBOL_GPL(crypto_unregister_skciphers); int skcipher_register_instance(struct crypto_template *tmpl, struct skcipher_instance *inst) { int err; err = skcipher_prepare_alg(&inst->alg); if (err) return err; return crypto_register_instance(tmpl, skcipher_crypto_instance(inst)); } EXPORT_SYMBOL_GPL(skcipher_register_instance); static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key, unsigned int keylen) { struct crypto_cipher *cipher = skcipher_cipher_simple(tfm); int err; crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK); crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_REQ_MASK); err = crypto_cipher_setkey(cipher, key, keylen); crypto_skcipher_set_flags(tfm, crypto_cipher_get_flags(cipher) & CRYPTO_TFM_RES_MASK); return err; } static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm) { struct skcipher_instance *inst = skcipher_alg_instance(tfm); struct crypto_spawn *spawn = skcipher_instance_ctx(inst); struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm); struct crypto_cipher *cipher; cipher = crypto_spawn_cipher(spawn); if (IS_ERR(cipher)) return PTR_ERR(cipher); ctx->cipher = cipher; return 0; } static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm) { struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm); crypto_free_cipher(ctx->cipher); } static void skcipher_free_instance_simple(struct skcipher_instance *inst) { crypto_drop_spawn(skcipher_instance_ctx(inst)); kfree(inst); } /** * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode * * Allocate an skcipher_instance for a simple block cipher mode of operation, * e.g. cbc or ecb. The instance context will have just a single crypto_spawn, * that for the underlying cipher. The {min,max}_keysize, ivsize, blocksize, * alignmask, and priority are set from the underlying cipher but can be * overridden if needed. The tfm context defaults to skcipher_ctx_simple, and * default ->setkey(), ->init(), and ->exit() methods are installed. * * @tmpl: the template being instantiated * @tb: the template parameters * @cipher_alg_ret: on success, a pointer to the underlying cipher algorithm is * returned here. It must be dropped with crypto_mod_put(). * * Return: a pointer to the new instance, or an ERR_PTR(). The caller still * needs to register the instance. */ struct skcipher_instance * skcipher_alloc_instance_simple(struct crypto_template *tmpl, struct rtattr **tb, struct crypto_alg **cipher_alg_ret) { struct crypto_attr_type *algt; struct crypto_alg *cipher_alg; struct skcipher_instance *inst; struct crypto_spawn *spawn; u32 mask; int err; algt = crypto_get_attr_type(tb); if (IS_ERR(algt)) return ERR_CAST(algt); if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) return ERR_PTR(-EINVAL); mask = CRYPTO_ALG_TYPE_MASK | crypto_requires_off(algt->type, algt->mask, CRYPTO_ALG_NEED_FALLBACK); cipher_alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, mask); if (IS_ERR(cipher_alg)) return ERR_CAST(cipher_alg); inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); if (!inst) { err = -ENOMEM; goto err_put_cipher_alg; } spawn = skcipher_instance_ctx(inst); err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name, cipher_alg); if (err) goto err_free_inst; err = crypto_init_spawn(spawn, cipher_alg, skcipher_crypto_instance(inst), CRYPTO_ALG_TYPE_MASK); if (err) goto err_free_inst; inst->free = skcipher_free_instance_simple; /* Default algorithm properties, can be overridden */ inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize; inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask; inst->alg.base.cra_priority = cipher_alg->cra_priority; inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize; inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize; inst->alg.ivsize = cipher_alg->cra_blocksize; /* Use skcipher_ctx_simple by default, can be overridden */ inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple); inst->alg.setkey = skcipher_setkey_simple; inst->alg.init = skcipher_init_tfm_simple; inst->alg.exit = skcipher_exit_tfm_simple; *cipher_alg_ret = cipher_alg; return inst; err_free_inst: kfree(inst); err_put_cipher_alg: crypto_mod_put(cipher_alg); return ERR_PTR(err); } EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Symmetric key cipher type");