Release 4.11 crypto/skcipher.c
/*
* 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>
*
* 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 <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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 31 | 100.00% | 1 | 100.00% |
Total | 31 | 100.00% | 1 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 48 | 100.00% | 1 | 100.00% |
Total | 48 | 100.00% | 1 | 100.00% |
static inline void skcipher_map_src(struct skcipher_walk *walk)
{
walk->src.virt.addr = skcipher_map(&walk->in);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 28 | 100.00% | 1 | 100.00% |
Total | 28 | 100.00% | 1 | 100.00% |
static inline void skcipher_map_dst(struct skcipher_walk *walk)
{
walk->dst.virt.addr = skcipher_map(&walk->out);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 28 | 100.00% | 1 | 100.00% |
Total | 28 | 100.00% | 1 | 100.00% |
static inline void skcipher_unmap_src(struct skcipher_walk *walk)
{
skcipher_unmap(&walk->in, walk->src.virt.addr);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 28 | 100.00% | 1 | 100.00% |
Total | 28 | 100.00% | 1 | 100.00% |
static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
{
skcipher_unmap(&walk->out, walk->dst.virt.addr);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 28 | 100.00% | 1 | 100.00% |
Total | 28 | 100.00% | 1 | 100.00% |
static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
{
return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 23 | 100.00% | 1 | 100.00% |
Total | 23 | 100.00% | 1 | 100.00% |
/* 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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 50 | 100.00% | 1 | 100.00% |
Total | 50 | 100.00% | 1 | 100.00% |
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 78 | 100.00% | 1 | 100.00% |
Total | 78 | 100.00% | 1 | 100.00% |
int skcipher_walk_done(struct skcipher_walk *walk, int err)
{
unsigned int n = walk->nbytes - err;
unsigned int nbytes;
nbytes = walk->total - n;
if (unlikely(err < 0)) {
nbytes = 0;
n = 0;
} else 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 (WARN_ON(err)) {
err = -EINVAL;
nbytes = 0;
} else
n = skcipher_done_slow(walk, n);
}
if (err > 0)
err = 0;
walk->total = nbytes;
walk->nbytes = nbytes;
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);
}
/* 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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 376 | 100.00% | 1 | 100.00% |
Total | 376 | 100.00% | 1 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 208 | 99.05% | 1 | 50.00% |
Ard Biesheuvel | 2 | 0.95% | 1 | 50.00% |
Total | 210 | 100.00% | 2 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 37 | 100.00% | 1 | 100.00% |
Total | 37 | 100.00% | 1 | 100.00% |
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 304 | 95.90% | 1 | 50.00% |
Ard Biesheuvel | 13 | 4.10% | 1 | 50.00% |
Total | 317 | 100.00% | 2 | 100.00% |
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 169 | 99.41% | 1 | 50.00% |
Ard Biesheuvel | 1 | 0.59% | 1 | 50.00% |
Total | 170 | 100.00% | 2 | 100.00% |
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 169 | 100.00% | 1 | 100.00% |
Total | 169 | 100.00% | 1 | 100.00% |
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 324 | 99.69% | 1 | 50.00% |
Ard Biesheuvel | 1 | 0.31% | 1 | 50.00% |
Total | 325 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL_GPL(skcipher_walk_next);
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);
/* 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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 172 | 99.42% | 1 | 50.00% |
Ard Biesheuvel | 1 | 0.58% | 1 | 50.00% |
Total | 173 | 100.00% | 2 | 100.00% |
static int skcipher_walk_first(struct skcipher_walk *walk)
{
walk->nbytes = 0;
if (WARN_ON_ONCE(in_irq()))
return -EDEADLK;
if (unlikely(!walk->total))
return 0;
walk->buffer = NULL;
if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
int err = skcipher_copy_iv(walk);
if (err)
return err;
}
walk->page = NULL;
walk->nbytes = walk->total;
return skcipher_walk_next(walk);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 104 | 100.00% | 1 | 100.00% |
Total | 104 | 100.00% | 1 | 100.00% |
static int skcipher_walk_skcipher(struct skcipher_walk *walk,
struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
scatterwalk_start(&walk->in, req->src);
scatterwalk_start(&walk->out, req->dst);
walk->total = req->cryptlen;
walk->iv = req->iv;
walk->oiv = req->iv;
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 137 | 98.56% | 1 | 50.00% |
Ard Biesheuvel | 2 | 1.44% | 1 | 50.00% |
Total | 139 | 100.00% | 2 | 100.00% |
int skcipher_walk_virt(struct skcipher_walk *walk,
struct skcipher_request *req, bool atomic)
{
int err;
walk->flags &= ~SKCIPHER_WALK_PHYS;
err = skcipher_walk_skcipher(walk, req);
walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
return err;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 52 | 100.00% | 1 | 100.00% |
Total | 52 | 100.00% | 1 | 100.00% |
EXPORT_SYMBOL_GPL(skcipher_walk_virt);
void skcipher_walk_atomise(struct skcipher_walk *walk)
{
walk->flags &= ~SKCIPHER_WALK_SLEEP;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 17 | 100.00% | 1 | 100.00% |
Total | 17 | 100.00% | 1 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 37 | 100.00% | 1 | 100.00% |
Total | 37 | 100.00% | 1 | 100.00% |
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->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);
walk->iv = req->iv;
walk->oiv = req->iv;
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;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 184 | 95.83% | 2 | 50.00% |
Ard Biesheuvel | 8 | 4.17% | 2 | 50.00% |
Total | 192 | 100.00% | 4 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 36 | 100.00% | 1 | 100.00% |
Total | 36 | 100.00% | 1 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 36 | 100.00% | 1 | 100.00% |
Total | 36 | 100.00% | 1 | 100.00% |
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);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 51 | 100.00% | 1 | 100.00% |
Total | 51 | 100.00% | 1 | 100.00% |
EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
{
if (alg->cra_type == &crypto_blkcipher_type)
return sizeof(struct crypto_blkcipher *);
if (alg->cra_type == &crypto_ablkcipher_type ||
alg->cra_type == &crypto_givcipher_type)
return sizeof(struct crypto_ablkcipher *);
return crypto_alg_extsize(alg);
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Herbert Xu | 59 | 100.00% | 2 | 100.00% |
Total | 59 | 100.00% | 2 | 100.00% |
static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
const u8 *key, unsigned int keylen)
{
struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
struct crypto_blkcipher *blkcipher = *ctx;
int err;
crypto_blkcipher_clear_flags(blkcipher,