return 0;
}
-static void gcm_sg_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg,
- unsigned int len)
+static void gcm_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg,
+ unsigned int len)
{
memset(gw, 0, sizeof(*gw));
gw->walk_bytes_remain = len;
scatterwalk_start(&gw->walk, sg);
}
-static int gcm_sg_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded)
+static inline unsigned int _gcm_sg_clamp_and_map(struct gcm_sg_walk *gw)
+{
+ struct scatterlist *nextsg;
+
+ gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain);
+ while (!gw->walk_bytes) {
+ nextsg = sg_next(gw->walk.sg);
+ if (!nextsg)
+ return 0;
+ scatterwalk_start(&gw->walk, nextsg);
+ gw->walk_bytes = scatterwalk_clamp(&gw->walk,
+ gw->walk_bytes_remain);
+ }
+ gw->walk_ptr = scatterwalk_map(&gw->walk);
+ return gw->walk_bytes;
+}
+
+static inline void _gcm_sg_unmap_and_advance(struct gcm_sg_walk *gw,
+ unsigned int nbytes)
+{
+ gw->walk_bytes_remain -= nbytes;
+ scatterwalk_unmap(&gw->walk);
+ scatterwalk_advance(&gw->walk, nbytes);
+ scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain);
+ gw->walk_ptr = NULL;
+}
+
+static int gcm_in_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded)
{
int n;
- /* minbytesneeded <= AES_BLOCK_SIZE */
if (gw->buf_bytes && gw->buf_bytes >= minbytesneeded) {
gw->ptr = gw->buf;
gw->nbytes = gw->buf_bytes;
goto out;
}
- gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain);
- if (!gw->walk_bytes) {
- scatterwalk_start(&gw->walk, sg_next(gw->walk.sg));
- gw->walk_bytes = scatterwalk_clamp(&gw->walk,
- gw->walk_bytes_remain);
+ if (!_gcm_sg_clamp_and_map(gw)) {
+ gw->ptr = NULL;
+ gw->nbytes = 0;
+ goto out;
}
- gw->walk_ptr = scatterwalk_map(&gw->walk);
if (!gw->buf_bytes && gw->walk_bytes >= minbytesneeded) {
gw->ptr = gw->walk_ptr;
n = min(gw->walk_bytes, AES_BLOCK_SIZE - gw->buf_bytes);
memcpy(gw->buf + gw->buf_bytes, gw->walk_ptr, n);
gw->buf_bytes += n;
- gw->walk_bytes_remain -= n;
- scatterwalk_unmap(&gw->walk);
- scatterwalk_advance(&gw->walk, n);
- scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain);
-
+ _gcm_sg_unmap_and_advance(gw, n);
if (gw->buf_bytes >= minbytesneeded) {
gw->ptr = gw->buf;
gw->nbytes = gw->buf_bytes;
goto out;
}
-
- gw->walk_bytes = scatterwalk_clamp(&gw->walk,
- gw->walk_bytes_remain);
- if (!gw->walk_bytes) {
- scatterwalk_start(&gw->walk, sg_next(gw->walk.sg));
- gw->walk_bytes = scatterwalk_clamp(&gw->walk,
- gw->walk_bytes_remain);
+ if (!_gcm_sg_clamp_and_map(gw)) {
+ gw->ptr = NULL;
+ gw->nbytes = 0;
+ goto out;
}
- gw->walk_ptr = scatterwalk_map(&gw->walk);
}
out:
return gw->nbytes;
}
-static void gcm_sg_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone)
+static int gcm_out_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded)
{
- int n;
+ if (gw->walk_bytes_remain == 0) {
+ gw->ptr = NULL;
+ gw->nbytes = 0;
+ goto out;
+ }
+ if (!_gcm_sg_clamp_and_map(gw)) {
+ gw->ptr = NULL;
+ gw->nbytes = 0;
+ goto out;
+ }
+
+ if (gw->walk_bytes >= minbytesneeded) {
+ gw->ptr = gw->walk_ptr;
+ gw->nbytes = gw->walk_bytes;
+ goto out;
+ }
+
+ scatterwalk_unmap(&gw->walk);
+ gw->walk_ptr = NULL;
+
+ gw->ptr = gw->buf;
+ gw->nbytes = sizeof(gw->buf);
+
+out:
+ return gw->nbytes;
+}
+
+static int gcm_in_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone)
+{
if (gw->ptr == NULL)
- return;
+ return 0;
if (gw->ptr == gw->buf) {
- n = gw->buf_bytes - bytesdone;
+ int n = gw->buf_bytes - bytesdone;
if (n > 0) {
memmove(gw->buf, gw->buf + bytesdone, n);
- gw->buf_bytes -= n;
+ gw->buf_bytes = n;
} else
gw->buf_bytes = 0;
- } else {
- gw->walk_bytes_remain -= bytesdone;
- scatterwalk_unmap(&gw->walk);
- scatterwalk_advance(&gw->walk, bytesdone);
- scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain);
- }
+ } else
+ _gcm_sg_unmap_and_advance(gw, bytesdone);
+
+ return bytesdone;
+}
+
+static int gcm_out_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone)
+{
+ int i, n;
+
+ if (gw->ptr == NULL)
+ return 0;
+
+ if (gw->ptr == gw->buf) {
+ for (i = 0; i < bytesdone; i += n) {
+ if (!_gcm_sg_clamp_and_map(gw))
+ return i;
+ n = min(gw->walk_bytes, bytesdone - i);
+ memcpy(gw->walk_ptr, gw->buf + i, n);
+ _gcm_sg_unmap_and_advance(gw, n);
+ }
+ } else
+ _gcm_sg_unmap_and_advance(gw, bytesdone);
+
+ return bytesdone;
}
static int gcm_aes_crypt(struct aead_request *req, unsigned int flags)
unsigned int pclen = req->cryptlen;
int ret = 0;
- unsigned int len, in_bytes, out_bytes,
+ unsigned int n, len, in_bytes, out_bytes,
min_bytes, bytes, aad_bytes, pc_bytes;
struct gcm_sg_walk gw_in, gw_out;
u8 tag[GHASH_DIGEST_SIZE];
*(u32 *)(param.j0 + ivsize) = 1;
memcpy(param.k, ctx->key, ctx->key_len);
- gcm_sg_walk_start(&gw_in, req->src, len);
- gcm_sg_walk_start(&gw_out, req->dst, len);
+ gcm_walk_start(&gw_in, req->src, len);
+ gcm_walk_start(&gw_out, req->dst, len);
do {
min_bytes = min_t(unsigned int,
aadlen > 0 ? aadlen : pclen, AES_BLOCK_SIZE);
- in_bytes = gcm_sg_walk_go(&gw_in, min_bytes);
- out_bytes = gcm_sg_walk_go(&gw_out, min_bytes);
+ in_bytes = gcm_in_walk_go(&gw_in, min_bytes);
+ out_bytes = gcm_out_walk_go(&gw_out, min_bytes);
bytes = min(in_bytes, out_bytes);
if (aadlen + pclen <= bytes) {
gw_in.ptr + aad_bytes, pc_bytes,
gw_in.ptr, aad_bytes);
- gcm_sg_walk_done(&gw_in, aad_bytes + pc_bytes);
- gcm_sg_walk_done(&gw_out, aad_bytes + pc_bytes);
+ n = aad_bytes + pc_bytes;
+ if (gcm_in_walk_done(&gw_in, n) != n)
+ return -ENOMEM;
+ if (gcm_out_walk_done(&gw_out, n) != n)
+ return -ENOMEM;
aadlen -= aad_bytes;
pclen -= pc_bytes;
} while (aadlen + pclen > 0);
projects / mirror_ubuntu-bionic-kernel.git / blobdiff