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authorLinus Torvalds <torvalds@linux-foundation.org>2025-12-03 11:28:38 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2025-12-03 11:28:38 -0800
commita619fe35ab41fded440d3762d4fbad84ff86a4d4 (patch)
tree2cc42a8bb9ec80f7850059c5cab383233c804957 /crypto/skcipher.c
parentc8321831480d80af01ce001bd6626fc130fd13b1 (diff)
parent48bc9da3c97c15f1ea24934bcb3b736acd30163d (diff)
downloadnet-a619fe35ab41fded440d3762d4fbad84ff86a4d4.tar.gz
Merge tag 'v6.19-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "API: - Rewrite memcpy_sglist from scratch - Add on-stack AEAD request allocation - Fix partial block processing in ahash Algorithms: - Remove ansi_cprng - Remove tcrypt tests for poly1305 - Fix EINPROGRESS processing in authenc - Fix double-free in zstd Drivers: - Use drbg ctr helper when reseeding xilinx-trng - Add support for PCI device 0x115A to ccp - Add support of paes in caam - Add support for aes-xts in dthev2 Others: - Use likely in rhashtable lookup - Fix lockdep false-positive in padata by removing a helper" * tag 'v6.19-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (71 commits) crypto: zstd - fix double-free in per-CPU stream cleanup crypto: ahash - Zero positive err value in ahash_update_finish crypto: ahash - Fix crypto_ahash_import with partial block data crypto: lib/mpi - use min() instead of min_t() crypto: ccp - use min() instead of min_t() hwrng: core - use min3() instead of nested min_t() crypto: aesni - ctr_crypt() use min() instead of min_t() crypto: drbg - Delete unused ctx from struct sdesc crypto: testmgr - Add missing DES weak and semi-weak key tests Revert "crypto: scatterwalk - Move skcipher walk and use it for memcpy_sglist" crypto: scatterwalk - Fix memcpy_sglist() to always succeed crypto: iaa - Request to add Kanchana P Sridhar to Maintainers. crypto: tcrypt - Remove unused poly1305 support crypto: ansi_cprng - Remove unused ansi_cprng algorithm crypto: asymmetric_keys - fix uninitialized pointers with free attribute KEYS: Avoid -Wflex-array-member-not-at-end warning crypto: ccree - Correctly handle return of sg_nents_for_len crypto: starfive - Correctly handle return of sg_nents_for_len crypto: iaa - Fix incorrect return value in save_iaa_wq() crypto: zstd - Remove unnecessary size_t cast ...
Diffstat (limited to 'crypto/skcipher.c')
-rw-r--r--crypto/skcipher.c261
1 files changed, 255 insertions, 6 deletions
diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 8fa5d9686d0850..14a820cb06c788 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c
@@ -17,6 +17,7 @@
#include <linux/cryptouser.h>
#include <linux/err.h>
#include <linux/kernel.h>
+#include <linux/mm.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
@@ -27,14 +28,258 @@
#define CRYPTO_ALG_TYPE_SKCIPHER_MASK 0x0000000e
+enum {
+ SKCIPHER_WALK_SLOW = 1 << 0,
+ SKCIPHER_WALK_COPY = 1 << 1,
+ SKCIPHER_WALK_DIFF = 1 << 2,
+ SKCIPHER_WALK_SLEEP = 1 << 3,
+};
+
static const struct crypto_type crypto_skcipher_type;
+static int skcipher_walk_next(struct skcipher_walk *walk);
+
+static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
+{
+ return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
+}
+
static inline struct skcipher_alg *__crypto_skcipher_alg(
struct crypto_alg *alg)
{
return container_of(alg, struct skcipher_alg, base);
}
+/**
+ * skcipher_walk_done() - finish one step of a skcipher_walk
+ * @walk: the skcipher_walk
+ * @res: number of bytes *not* processed (>= 0) from walk->nbytes,
+ * or a -errno value to terminate the walk due to an error
+ *
+ * This function cleans up after one step of walking through the source and
+ * destination scatterlists, and advances to the next step if applicable.
+ * walk->nbytes is set to the number of bytes available in the next step,
+ * walk->total is set to the new total number of bytes remaining, and
+ * walk->{src,dst}.virt.addr is set to the next pair of data pointers. If there
+ * is no more data, or if an error occurred (i.e. -errno return), then
+ * walk->nbytes and walk->total are set to 0 and all resources owned by the
+ * skcipher_walk are freed.
+ *
+ * Return: 0 or a -errno value. If @res was a -errno value then it will be
+ * returned, but other errors may occur too.
+ */
+int skcipher_walk_done(struct skcipher_walk *walk, int res)
+{
+ unsigned int n = walk->nbytes; /* num bytes processed this step */
+ unsigned int total = 0; /* new total remaining */
+
+ if (!n)
+ goto finish;
+
+ if (likely(res >= 0)) {
+ n -= res; /* subtract num bytes *not* processed */
+ total = walk->total - n;
+ }
+
+ if (likely(!(walk->flags & (SKCIPHER_WALK_SLOW |
+ SKCIPHER_WALK_COPY |
+ SKCIPHER_WALK_DIFF)))) {
+ scatterwalk_advance(&walk->in, n);
+ } else if (walk->flags & SKCIPHER_WALK_DIFF) {
+ scatterwalk_done_src(&walk->in, n);
+ } else if (walk->flags & SKCIPHER_WALK_COPY) {
+ scatterwalk_advance(&walk->in, n);
+ scatterwalk_map(&walk->out);
+ memcpy(walk->out.addr, walk->page, n);
+ } else { /* SKCIPHER_WALK_SLOW */
+ if (res > 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.
+ */
+ res = -EINVAL;
+ total = 0;
+ } else
+ memcpy_to_scatterwalk(&walk->out, walk->out.addr, n);
+ goto dst_done;
+ }
+
+ scatterwalk_done_dst(&walk->out, n);
+dst_done:
+
+ if (res > 0)
+ res = 0;
+
+ walk->total = total;
+ walk->nbytes = 0;
+
+ if (total) {
+ if (walk->flags & SKCIPHER_WALK_SLEEP)
+ cond_resched();
+ walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
+ SKCIPHER_WALK_DIFF);
+ 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->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 res;
+}
+EXPORT_SYMBOL_GPL(skcipher_walk_done);
+
+static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
+{
+ unsigned alignmask = walk->alignmask;
+ unsigned n;
+ void *buffer;
+
+ if (!walk->buffer)
+ walk->buffer = walk->page;
+ buffer = walk->buffer;
+ if (!buffer) {
+ /* Min size for a buffer of bsize bytes aligned to alignmask */
+ n = bsize + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
+
+ buffer = kzalloc(n, skcipher_walk_gfp(walk));
+ if (!buffer)
+ return skcipher_walk_done(walk, -ENOMEM);
+ walk->buffer = buffer;
+ }
+
+ buffer = PTR_ALIGN(buffer, alignmask + 1);
+ memcpy_from_scatterwalk(buffer, &walk->in, bsize);
+ walk->out.__addr = buffer;
+ walk->in.__addr = walk->out.addr;
+
+ walk->nbytes = bsize;
+ walk->flags |= SKCIPHER_WALK_SLOW;
+
+ return 0;
+}
+
+static int skcipher_next_copy(struct skcipher_walk *walk)
+{
+ void *tmp = walk->page;
+
+ scatterwalk_map(&walk->in);
+ memcpy(tmp, walk->in.addr, walk->nbytes);
+ scatterwalk_unmap(&walk->in);
+ /*
+ * walk->in is advanced later when the number of bytes actually
+ * processed (which might be less than walk->nbytes) is known.
+ */
+
+ walk->in.__addr = tmp;
+ walk->out.__addr = tmp;
+ return 0;
+}
+
+static int skcipher_next_fast(struct skcipher_walk *walk)
+{
+ unsigned long diff;
+
+ diff = offset_in_page(walk->in.offset) -
+ offset_in_page(walk->out.offset);
+ diff |= (u8 *)(sg_page(walk->in.sg) + (walk->in.offset >> PAGE_SHIFT)) -
+ (u8 *)(sg_page(walk->out.sg) + (walk->out.offset >> PAGE_SHIFT));
+
+ scatterwalk_map(&walk->out);
+ walk->in.__addr = walk->out.__addr;
+
+ if (diff) {
+ walk->flags |= SKCIPHER_WALK_DIFF;
+ scatterwalk_map(&walk->in);
+ }
+
+ return 0;
+}
+
+static int skcipher_walk_next(struct skcipher_walk *walk)
+{
+ unsigned int bsize;
+ unsigned int n;
+
+ 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:
+ return skcipher_next_slow(walk, bsize);
+ }
+ walk->nbytes = n;
+
+ 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->flags |= SKCIPHER_WALK_COPY;
+ return skcipher_next_copy(walk);
+ }
+
+ return skcipher_next_fast(walk);
+}
+
+static int skcipher_copy_iv(struct skcipher_walk *walk)
+{
+ unsigned alignmask = walk->alignmask;
+ unsigned ivsize = walk->ivsize;
+ unsigned aligned_stride = ALIGN(walk->stride, alignmask + 1);
+ unsigned size;
+ u8 *iv;
+
+ /* Min size for a buffer of stride + ivsize, aligned to alignmask */
+ size = aligned_stride + ivsize +
+ (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
+
+ walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
+ if (!walk->buffer)
+ return -ENOMEM;
+
+ iv = PTR_ALIGN(walk->buffer, alignmask + 1) + aligned_stride;
+
+ walk->iv = memcpy(iv, walk->iv, walk->ivsize);
+ return 0;
+}
+
+static int skcipher_walk_first(struct skcipher_walk *walk)
+{
+ if (WARN_ON_ONCE(in_hardirq()))
+ 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);
+}
+
int skcipher_walk_virt(struct skcipher_walk *__restrict walk,
struct skcipher_request *__restrict req, bool atomic)
{
@@ -49,8 +294,10 @@ int skcipher_walk_virt(struct skcipher_walk *__restrict walk,
walk->nbytes = 0;
walk->iv = req->iv;
walk->oiv = req->iv;
- if (!(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP))
- atomic = true;
+ if ((req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) && !atomic)
+ walk->flags = SKCIPHER_WALK_SLEEP;
+ else
+ walk->flags = 0;
if (unlikely(!walk->total))
return 0;
@@ -67,7 +314,7 @@ int skcipher_walk_virt(struct skcipher_walk *__restrict walk,
else
walk->stride = alg->walksize;
- return skcipher_walk_first(walk, atomic);
+ return skcipher_walk_first(walk);
}
EXPORT_SYMBOL_GPL(skcipher_walk_virt);
@@ -80,8 +327,10 @@ static int skcipher_walk_aead_common(struct skcipher_walk *__restrict walk,
walk->nbytes = 0;
walk->iv = req->iv;
walk->oiv = req->iv;
- if (!(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP))
- atomic = true;
+ if ((req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) && !atomic)
+ walk->flags = SKCIPHER_WALK_SLEEP;
+ else
+ walk->flags = 0;
if (unlikely(!walk->total))
return 0;
@@ -94,7 +343,7 @@ static int skcipher_walk_aead_common(struct skcipher_walk *__restrict walk,
walk->ivsize = crypto_aead_ivsize(tfm);
walk->alignmask = crypto_aead_alignmask(tfm);
- return skcipher_walk_first(walk, atomic);
+ return skcipher_walk_first(walk);
}
int skcipher_walk_aead_encrypt(struct skcipher_walk *__restrict walk,