LU-14677 sec: migrate/extend/split on encrypted file

[fs/lustre-release.git] / lustre / llite / namei.c

diff --git a/lustre/llite/namei.c b/lustre/llite/namei.c
index cbe3aa6..29d4806 100644 (file)
--- a/lustre/llite/namei.c
+++ b/lustre/llite/namei.c
@@ -32,6 +32,7 @@
 #include <linux/fs.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/file.h>
 #include <linux/quotaops.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
@@ -882,9 +883,90 @@ static struct dentry *ll_lookup_it(struct inode *parent, struct dentry *dentry,
                        *secctxlen = 0;
        }
        if (it->it_op & IT_CREAT && encrypt) {
-               rc = llcrypt_inherit_context(parent, NULL, op_data, false);
-               if (rc)
-                       GOTO(out, retval = ERR_PTR(rc));
+               /* Volatile file name may look like:
+                * <parent>/LUSTRE_VOLATILE_HDR:<mdt_index>:<random>:fd=<fd>
+                * where fd is opened descriptor of reference file.
+                */
+               if (unlikely(filename_is_volatile(dentry->d_name.name,
+                                                 dentry->d_name.len, NULL))) {
+                       int ctx_size = LLCRYPT_ENC_CTX_SIZE;
+                       struct lustre_sb_info *lsi;
+                       struct file *ref_file;
+                       struct inode *ref_inode;
+                       char *p, *q, *fd_str;
+                       void *ctx;
+                       int fd;
+
+                       p = strnstr(dentry->d_name.name, ":fd=",
+                                   dentry->d_name.len);
+                       if (!p || strlen(p + 4) == 0)
+                               GOTO(out, retval = ERR_PTR(-EINVAL));
+
+                       q = strchrnul(p + 4, ':');
+                       fd_str = kstrndup(p + 4, q - p - 4, GFP_NOFS);
+                       if (!fd_str)
+                               GOTO(out, retval = ERR_PTR(-ENOMEM));
+                       rc = kstrtouint(fd_str, 10, &fd);
+                       kfree(fd_str);
+                       if (rc)
+                               GOTO(inherit, rc = -EINVAL);
+
+                       ref_file = fget(fd);
+                       if (!ref_file)
+                               GOTO(inherit, rc = -EINVAL);
+
+                       ref_inode = file_inode(ref_file);
+                       if (!ref_inode) {
+                               fput(ref_file);
+                               GOTO(inherit, rc = -EINVAL);
+                       }
+
+                       lsi = s2lsi(ref_inode->i_sb);
+
+getctx:
+                       OBD_ALLOC(ctx, ctx_size);
+                       if (!ctx)
+                               GOTO(out, retval = ERR_PTR(-ENOMEM));
+
+#ifdef CONFIG_LL_ENCRYPTION
+                       rc = lsi->lsi_cop->get_context(ref_inode,
+                                                      ctx, ctx_size);
+#else
+                       rc = -ENODATA;
+#endif
+                       if (rc == -ERANGE) {
+                               OBD_FREE(ctx, ctx_size);
+                               ctx_size *= 2;
+                               goto getctx;
+                       }
+                       fput(ref_file);
+                       if (rc < 0) {
+                               OBD_FREE(ctx, ctx_size);
+                               GOTO(inherit, rc);
+                       }
+
+                       op_data->op_file_encctx_size = rc;
+                       if (rc == ctx_size) {
+                               op_data->op_file_encctx = ctx;
+                       } else {
+                               OBD_ALLOC(op_data->op_file_encctx,
+                                         op_data->op_file_encctx_size);
+                               if (!op_data->op_file_encctx) {
+                                       OBD_FREE(ctx, ctx_size);
+                                       GOTO(out, retval = ERR_PTR(-ENOMEM));
+                               }
+                               memcpy(op_data->op_file_encctx, ctx,
+                                      op_data->op_file_encctx_size);
+                               OBD_FREE(ctx, ctx_size);
+                       }
+
+               } else {
+inherit:
+                       rc = llcrypt_inherit_context(parent, NULL, op_data,
+                                                    false);
+                       if (rc)
+                               GOTO(out, retval = ERR_PTR(rc));
+               }
                if (encctx != NULL)
                        *encctx = op_data->op_file_encctx;
                if (encctxlen != NULL)