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Diffstat (limited to 'fs/cifs/smb2ops.c')
-rw-r--r--fs/cifs/smb2ops.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index ef8b2a8363b3..54b49358eaaf 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -20,6 +20,8 @@
#include <linux/pagemap.h>
#include <linux/vfs.h>
#include <linux/falloc.h>
+#include <linux/scatterlist.h>
+#include <crypto/aead.h>
#include "cifsglob.h"
#include "smb2pdu.h"
#include "smb2proto.h"
@@ -1547,6 +1549,256 @@ smb2_dir_needs_close(struct cifsFileInfo *cfile)
return !cfile->invalidHandle;
}
+static void
+fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, struct smb_rqst *old_rq)
+{
+ struct smb2_sync_hdr *shdr =
+ (struct smb2_sync_hdr *)old_rq->rq_iov[1].iov_base;
+ unsigned int orig_len = get_rfc1002_length(old_rq->rq_iov[0].iov_base);
+
+ memset(tr_hdr, 0, sizeof(struct smb2_transform_hdr));
+ tr_hdr->ProtocolId = SMB2_TRANSFORM_PROTO_NUM;
+ tr_hdr->OriginalMessageSize = cpu_to_le32(orig_len);
+ tr_hdr->Flags = cpu_to_le16(0x01);
+ get_random_bytes(&tr_hdr->Nonce, SMB3_AES128CMM_NONCE);
+ memcpy(&tr_hdr->SessionId, &shdr->SessionId, 8);
+ inc_rfc1001_len(tr_hdr, sizeof(struct smb2_transform_hdr) - 4);
+ inc_rfc1001_len(tr_hdr, orig_len);
+}
+
+static struct scatterlist *
+init_sg(struct smb_rqst *rqst, u8 *sign)
+{
+ unsigned int sg_len = rqst->rq_nvec + rqst->rq_npages + 1;
+ unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 24;
+ struct scatterlist *sg;
+ unsigned int i;
+ unsigned int j;
+
+ sg = kmalloc_array(sg_len, sizeof(struct scatterlist), GFP_KERNEL);
+ if (!sg)
+ return NULL;
+
+ sg_init_table(sg, sg_len);
+ sg_set_buf(&sg[0], rqst->rq_iov[0].iov_base + 24, assoc_data_len);
+ for (i = 1; i < rqst->rq_nvec; i++)
+ sg_set_buf(&sg[i], rqst->rq_iov[i].iov_base,
+ rqst->rq_iov[i].iov_len);
+ for (j = 0; i < sg_len - 1; i++, j++) {
+ unsigned int len = (j < rqst->rq_npages - 1) ? rqst->rq_pagesz
+ : rqst->rq_tailsz;
+ sg_set_page(&sg[i], rqst->rq_pages[j], len, 0);
+ }
+ sg_set_buf(&sg[sg_len - 1], sign, SMB2_SIGNATURE_SIZE);
+ return sg;
+}
+
+struct cifs_crypt_result {
+ int err;
+ struct completion completion;
+};
+
+static void cifs_crypt_complete(struct crypto_async_request *req, int err)
+{
+ struct cifs_crypt_result *res = req->data;
+
+ if (err == -EINPROGRESS)
+ return;
+
+ res->err = err;
+ complete(&res->completion);
+}
+
+/*
+ * Encrypt or decrypt @rqst message. @rqst has the following format:
+ * iov[0] - transform header (associate data),
+ * iov[1-N] and pages - data to encrypt.
+ * On success return encrypted data in iov[1-N] and pages, leave iov[0]
+ * untouched.
+ */
+static int
+crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
+{
+ struct smb2_transform_hdr *tr_hdr =
+ (struct smb2_transform_hdr *)rqst->rq_iov[0].iov_base;
+ unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 24;
+ struct cifs_ses *ses;
+ int rc = 0;
+ struct scatterlist *sg;
+ u8 sign[SMB2_SIGNATURE_SIZE] = {};
+ struct aead_request *req;
+ char *iv;
+ unsigned int iv_len;
+ struct cifs_crypt_result result = {0, };
+ struct crypto_aead *tfm;
+ unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
+
+ init_completion(&result.completion);
+
+ ses = smb2_find_smb_ses(server, tr_hdr->SessionId);
+ if (!ses) {
+ cifs_dbg(VFS, "%s: Could not find session\n", __func__);
+ return 0;
+ }
+
+ rc = smb3_crypto_aead_allocate(server);
+ if (rc) {
+ cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
+ return rc;
+ }
+
+ tfm = enc ? server->secmech.ccmaesencrypt :
+ server->secmech.ccmaesdecrypt;
+ rc = crypto_aead_setkey(tfm, enc ? ses->smb3encryptionkey :
+ ses->smb3decryptionkey, SMB3_SIGN_KEY_SIZE);
+ if (rc) {
+ cifs_dbg(VFS, "%s: Failed to set aead key %d\n", __func__, rc);
+ return rc;
+ }
+
+ rc = crypto_aead_setauthsize(tfm, SMB2_SIGNATURE_SIZE);
+ if (rc) {
+ cifs_dbg(VFS, "%s: Failed to set authsize %d\n", __func__, rc);
+ return rc;
+ }
+
+ req = aead_request_alloc(tfm, GFP_KERNEL);
+ if (!req) {
+ cifs_dbg(VFS, "%s: Failed to alloc aead request", __func__);
+ return -ENOMEM;
+ }
+
+ if (!enc) {
+ memcpy(sign, &tr_hdr->Signature, SMB2_SIGNATURE_SIZE);
+ crypt_len += SMB2_SIGNATURE_SIZE;
+ }
+
+ sg = init_sg(rqst, sign);
+ if (!sg) {
+ cifs_dbg(VFS, "%s: Failed to init sg %d", __func__, rc);
+ goto free_req;
+ }
+
+ iv_len = crypto_aead_ivsize(tfm);
+ iv = kzalloc(iv_len, GFP_KERNEL);
+ if (!iv) {
+ cifs_dbg(VFS, "%s: Failed to alloc IV", __func__);
+ goto free_sg;
+ }
+ iv[0] = 3;
+ memcpy(iv + 1, (char *)tr_hdr->Nonce, SMB3_AES128CMM_NONCE);
+
+ aead_request_set_crypt(req, sg, sg, crypt_len, iv);
+ aead_request_set_ad(req, assoc_data_len);
+
+ aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ cifs_crypt_complete, &result);
+
+ rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);
+
+ if (rc == -EINPROGRESS || rc == -EBUSY) {
+ wait_for_completion(&result.completion);
+ rc = result.err;
+ }
+
+ if (!rc && enc)
+ memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);
+
+ kfree(iv);
+free_sg:
+ kfree(sg);
+free_req:
+ kfree(req);
+ return rc;
+}
+
+static int
+smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
+ struct smb_rqst *old_rq)
+{
+ struct kvec *iov;
+ struct page **pages;
+ struct smb2_transform_hdr *tr_hdr;
+ unsigned int npages = old_rq->rq_npages;
+ int i;
+ int rc = -ENOMEM;
+
+ pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
+ if (!pages)
+ return rc;
+
+ new_rq->rq_pages = pages;
+ new_rq->rq_npages = old_rq->rq_npages;
+ new_rq->rq_pagesz = old_rq->rq_pagesz;
+ new_rq->rq_tailsz = old_rq->rq_tailsz;
+
+ for (i = 0; i < npages; i++) {
+ pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
+ if (!pages[i])
+ goto err_free_pages;
+ }
+
+ iov = kmalloc_array(old_rq->rq_nvec, sizeof(struct kvec), GFP_KERNEL);
+ if (!iov)
+ goto err_free_pages;
+
+ /* copy all iovs from the old except the 1st one (rfc1002 length) */
+ memcpy(&iov[1], &old_rq->rq_iov[1],
+ sizeof(struct kvec) * (old_rq->rq_nvec - 1));
+ new_rq->rq_iov = iov;
+ new_rq->rq_nvec = old_rq->rq_nvec;
+
+ tr_hdr = kmalloc(sizeof(struct smb2_transform_hdr), GFP_KERNEL);
+ if (!tr_hdr)
+ goto err_free_iov;
+
+ /* fill the 1st iov with a transform header */
+ fill_transform_hdr(tr_hdr, old_rq);
+ new_rq->rq_iov[0].iov_base = tr_hdr;
+ new_rq->rq_iov[0].iov_len = sizeof(struct smb2_transform_hdr);
+
+ /* copy pages form the old */
+ for (i = 0; i < npages; i++) {
+ char *dst = kmap(new_rq->rq_pages[i]);
+ char *src = kmap(old_rq->rq_pages[i]);
+ unsigned int len = (i < npages - 1) ? new_rq->rq_pagesz :
+ new_rq->rq_tailsz;
+ memcpy(dst, src, len);
+ kunmap(new_rq->rq_pages[i]);
+ kunmap(old_rq->rq_pages[i]);
+ }
+
+ rc = crypt_message(server, new_rq, 1);
+ cifs_dbg(FYI, "encrypt message returned %d", rc);
+ if (rc)
+ goto err_free_tr_hdr;
+
+ return rc;
+
+err_free_tr_hdr:
+ kfree(tr_hdr);
+err_free_iov:
+ kfree(iov);
+err_free_pages:
+ for (i = i - 1; i >= 0; i--)
+ put_page(pages[i]);
+ kfree(pages);
+ return rc;
+}
+
+static void
+smb3_free_transform_rq(struct smb_rqst *rqst)
+{
+ int i = rqst->rq_npages - 1;
+
+ for (; i >= 0; i--)
+ put_page(rqst->rq_pages[i]);
+ kfree(rqst->rq_pages);
+ /* free transform header */
+ kfree(rqst->rq_iov[0].iov_base);
+ kfree(rqst->rq_iov);
+}
+
struct smb_version_operations smb20_operations = {
.compare_fids = smb2_compare_fids,
.setup_request = smb2_setup_request,
@@ -1793,6 +2045,8 @@ struct smb_version_operations smb30_operations = {
.dir_needs_close = smb2_dir_needs_close,
.fallocate = smb3_fallocate,
.enum_snapshots = smb3_enum_snapshots,
+ .init_transform_rq = smb3_init_transform_rq,
+ .free_transform_rq = smb3_free_transform_rq,
};
#ifdef CONFIG_CIFS_SMB311
@@ -1881,6 +2135,8 @@ struct smb_version_operations smb311_operations = {
.dir_needs_close = smb2_dir_needs_close,
.fallocate = smb3_fallocate,
.enum_snapshots = smb3_enum_snapshots,
+ .init_transform_rq = smb3_init_transform_rq,
+ .free_transform_rq = smb3_free_transform_rq,
};
#endif /* CIFS_SMB311 */