4 files changed, 155 insertions, 0 deletions
diff --git a/src/sys/include/os/filedesc.h b/src/sys/include/os/filedesc.h
index a6a2ac5..95400ed 100644
--- a/src/sys/include/os/filedesc.h
+++ b/src/sys/include/os/filedesc.h
@@ -30,6 +30,7 @@
 #ifndef _OS_FILEDESC_H_
 #define _OS_FILEDESC_H_ 1
 
+#include <sys/seek.h>
 #include <sys/types.h>
 #include <os/vnode.h>
 
@@ -51,6 +52,18 @@ struct filedesc {
 };
 
 /*
+ * Allocate a file descriptor from a specific process's
+ * file descriptor table
+ *
+ * @procp: Process to allocate fd from
+ * @fd_res: Result pointer is written here
+ *
+ * Returns zero on success, otherwise a less than
+ * zero value upon failure
+ */
+int fd_alloc(struct proc *procp, struct filedesc **fd_res);
+
+/*
  * Duplicate a file descriptor
  *
  * @procp: Process to duplicate from
@@ -62,6 +75,18 @@ struct filedesc {
 struct filedesc *fd_dup(struct proc *procp, int fd);
 
 /*
+ * Look up a file descriptor that belongs to a specific
+ * process by using its fd number
+ *
+ * @procp: Process to look up
+ * @fd: File descriptor number
+ *
+ * Returns the file descriptor pointer on success,
+ * otherwise a less than zero value on failure
+ */
+struct filedesc *fd_get(struct proc *procp, int fd);
+
+/*
  * Initialize a process file descriptor table
  * and set up standard streams
  *
@@ -117,4 +142,13 @@ ssize_t write(int fd, const void *buf, size_t count);
  */
 ssize_t read(int fd, void *buf, size_t count);
 
+/*
+ * Reposition the file offset of a file
+ *
+ * @fd: File descriptor to reposition
+ * @offset: Offset to move `fd' to
+ * @whence: How it should be repositioned
+ */
+off_t lseek(int fd, off_t offset, int whence);
+
 #endif  /* !_OS_FILEDESC_H_ */
diff --git a/src/sys/include/os/kalloc.h b/src/sys/include/os/kalloc.h
index 143c4f9..aaaaa74 100644
--- a/src/sys/include/os/kalloc.h
+++ b/src/sys/include/os/kalloc.h
@@ -48,6 +48,14 @@
 void *kalloc(size_t sz);
 
 /*
+ * Reallocates memory pool created by `dynalloc()'
+ *
+ * @old_ptr: Pointer to old pool.
+ * @newsize: Size of new pool.
+ */
+void *krealloc(void *old_ptr, size_t newsize);
+
+/*
  * Free a chunk of memory given to by
  * `ptr'
  *
diff --git a/src/sys/include/os/ucred.h b/src/sys/include/os/ucred.h
new file mode 100644
index 0000000..6e3e4b4
--- /dev/null
+++ b/src/sys/include/os/ucred.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2025 Ian Marco Moffett and L5 engineers
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _OS_UCRED_H_
+#define _OS_UCRED_H_ 1
+
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/ucred.h>
+#include <sys/proc.h>
+
+/*
+ * Initialize user credientials
+ *
+ * @proc: Current process
+ * @cred: credientials to initialize
+ *
+ * XXX: 'proc' being NULL drops the creds to root
+ *
+ * Returns zero on success, otherwise a less
+ * than zero value on failure.
+ */
+int ucred_init(struct proc *proc, struct ucred *cred);
+
+/*
+ * Set effective user ID
+ */
+int seteuid(uid_t euid);
+
+/*
+ * Set EUID system call
+ */
+scret_t sys_seteuid(struct syscall_args *scargs);
+
+#endif  /* !_OS_UCRED_H_ */
diff --git a/src/sys/include/os/vnode.h b/src/sys/include/os/vnode.h
index 1bef1e2..9d8a3e6 100644
--- a/src/sys/include/os/vnode.h
+++ b/src/sys/include/os/vnode.h
@@ -32,6 +32,7 @@
 
 #include <sys/types.h>
 #include <sys/atomic.h>
+#include <sys/namei.h>
 
 /* Forward declarations */
 struct vnode;
@@ -43,12 +44,16 @@ struct vop;
  * @VTYPE_NONE: Vnode is yet to be assigned a type
  * @VTYPE_FILE: Vnode references a file
  * @VTYPE_DIR:  Vnode references a directory
+ * @VTYPE_SOCK: Vnode references a socket
+ * @VTYPE_CDEV: Vnode references a character device
  * @__N_VTYPE:  Number of valid nodes on the system
  */
 typedef enum {
     VTYPE_NONE,
     VTYPE_FILE,
     VTYPE_DIR,
+    VTYPE_SOCK,
+    VTYPE_CDEV,
     __N_VTYPE
 } vtype_t;
 
@@ -83,12 +88,35 @@ struct vop_rw_data {
 };
 
 /*
+ * Arguments to create an entry within a
+ * filesystem
+ *
+ * @ndp: Path component to create
+ * @vtype: Vnode type
+ */
+struct vop_create_args {
+    struct nameidata *ndp;
+    vtype_t vtype;
+};
+
+/*
+ * Represents attributes of a vnode
+ *
+ * @size: File size in bytes
+ */
+struct vattr {
+    size_t size;
+};
+
+/*
  * Represents operations that can be performed on
  * a specific vnode. These are implemented as callbacks
  */
 struct vop {
+    int(*getattr)(struct vnode *vp, struct vattr *res);
     int(*lookup)(struct vop_lookup_args *args);
     int(*reclaim)(struct vnode *vp, int flags);
+    int(*create)(struct vop_create_args *args);
     ssize_t(*write)(struct vop_rw_data *data);
     ssize_t(*read)(struct vop_rw_data *data);
 };
@@ -176,4 +204,28 @@ ssize_t vop_read(struct vnode *vp, char *data, off_t off, size_t len);
  */
 int vop_reclaim(struct vnode *vp, int flags);
 
+/*
+ * Create a node within a specific filesystem or
+ * directory
+ *
+ * @vp: Vnode of parent directory
+ * @ndp: Namei descriptor of path component
+ * @type: Vnode type to create with
+ *
+ * Returns zero on success, otherwise a less than zero
+ * value on failure.
+ */
+int vop_create(struct vnode *vp, struct nameidata *ndp, vtype_t type);
+
+/*
+ * Get the attributes of a file
+ *
+ * @vp: Vnode of file to get attributes of
+ * @res: Result of file to get attr of
+ *
+ * Returns zero on success, otherwise a less than
+ * zero value on failure
+ */
+int vop_getattr(struct vnode *vp, struct vattr *res);
+
 #endif  /* !_OS_VNODE_H_ */