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/* SPDX-License-Identifier: GPL-2.0+ */
#ifndef __PXE_UTILS_H
#define __PXE_UTILS_H
#include <linux/list.h>
/*
* A note on the pxe file parser.
*
* We're parsing files that use syslinux grammar, which has a few quirks.
* String literals must be recognized based on context - there is no
* quoting or escaping support. There's also nothing to explicitly indicate
* when a label section completes. We deal with that by ending a label
* section whenever we see a line that doesn't include.
*
* As with the syslinux family, this same file format could be reused in the
* future for non pxe purposes. The only action it takes during parsing that
* would throw this off is handling of include files. It assumes we're using
* pxe, and does a tftp download of a file listed as an include file in the
* middle of the parsing operation. That could be handled by refactoring it to
* take a 'include file getter' function.
*/
/*
* Describes a single label given in a pxe file.
*
* Create these with the 'label_create' function given below.
*
* name - the name of the menu as given on the 'menu label' line.
* kernel - the path to the kernel file to use for this label.
* append - kernel command line to use when booting this label
* initrd - path to the initrd to use for this label.
* attempted - 0 if we haven't tried to boot this label, 1 if we have.
* localboot - 1 if this label specified 'localboot', 0 otherwise.
* list - lets these form a list, which a pxe_menu struct will hold.
*/
struct pxe_label {
char num[4];
char *name;
char *menu;
char *kernel;
char *config;
char *append;
char *initrd;
char *fdt;
char *fdtdir;
char *fdtoverlays;
int ipappend;
int attempted;
int localboot;
int localboot_val;
struct list_head list;
};
/*
* Describes a pxe menu as given via pxe files.
*
* title - the name of the menu as given by a 'menu title' line.
* default_label - the name of the default label, if any.
* bmp - the bmp file name which is displayed in background
* timeout - time in tenths of a second to wait for a user key-press before
* booting the default label.
* prompt - if 0, don't prompt for a choice unless the timeout period is
* interrupted. If 1, always prompt for a choice regardless of
* timeout.
* labels - a list of labels defined for the menu.
*/
struct pxe_menu {
char *title;
char *default_label;
char *bmp;
int timeout;
int prompt;
struct list_head labels;
};
struct pxe_context;
typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path,
char *file_addr);
/**
* struct pxe_context - context information for PXE parsing
*
* @cmdtp: Pointer to command table to use when calling other commands
* @getfile: Function called by PXE to read a file
* @userdata: Data the caller requires for @getfile
* @allow_abs_path: true to allow absolute paths
* @bootdir: Directory that files are loaded from ("" if no directory). This is
* allocated
*/
struct pxe_context {
struct cmd_tbl *cmdtp;
/**
* getfile() - read a file
*
* @ctx: PXE context
* @file_path: Path to the file
* @file_addr: String containing the hex address to put the file in
* memory
* Return 0 if OK, -ve on error
*/
pxe_getfile_func getfile;
void *userdata;
bool allow_abs_path;
char *bootdir;
};
/**
* destroy_pxe_menu() - Destroy an allocated pxe structure
*
* Free the memory used by a pxe_menu and its labels
*
* @cfg: Config to destroy, previous returned from parse_pxefile()
*/
void destroy_pxe_menu(struct pxe_menu *cfg);
/**
* get_pxe_file() - Read a file
*
* Retrieve the file at 'file_path' to the locate given by 'file_addr'. If
* 'bootfile' was specified in the environment, the path to bootfile will be
* prepended to 'file_path' and the resulting path will be used.
*
* @ctx: PXE context
* @file_path: Path to file
* @file_addr: Address to place file
* Returns 1 on success, or < 0 for error
*/
int get_pxe_file(struct pxe_context *ctx, const char *file_path,
ulong file_addr);
/**
* get_pxelinux_path() - Read a file from the same place as pxelinux.cfg
*
* Retrieves a file in the 'pxelinux.cfg' folder. Since this uses get_pxe_file()
* to do the hard work, the location of the 'pxelinux.cfg' folder is generated
* from the bootfile path, as described in get_pxe_file().
*
* @ctx: PXE context
* @file: Relative path to file
* @pxefile_addr_r: Address to load file
* Returns 1 on success or < 0 on error.
*/
int get_pxelinux_path(struct pxe_context *ctx, const char *file,
ulong pxefile_addr_r);
/**
* handle_pxe_menu() - Boot the system as prescribed by a pxe_menu.
*
* Use the menu system to either get the user's choice or the default, based
* on config or user input. If there is no default or user's choice,
* attempted to boot labels in the order they were given in pxe files.
* If the default or user's choice fails to boot, attempt to boot other
* labels in the order they were given in pxe files.
*
* If this function returns, there weren't any labels that successfully
* booted, or the user interrupted the menu selection via ctrl+c.
*
* @ctx: PXE context
* @cfg: PXE menu
*/
void handle_pxe_menu(struct pxe_context *ctx, struct pxe_menu *cfg);
/**
* parse_pxefile() - Parsing a pxe file
*
* This is only used for the top-level file.
*
* @ctx: PXE context (provided by the caller)
* Returns NULL if there is an error, otherwise, returns a pointer to a
* pxe_menu struct populated with the results of parsing the pxe file (and any
* files it includes). The resulting pxe_menu struct can be free()'d by using
* the destroy_pxe_menu() function.
*/
struct pxe_menu *parse_pxefile(struct pxe_context *ctx, ulong menucfg);
/**
* format_mac_pxe() - Convert a MAC address to PXE format
*
* Convert an ethaddr from the environment to the format used by pxelinux
* filenames based on mac addresses. Convert's ':' to '-', and adds "01-" to
* the beginning of the ethernet address to indicate a hardware type of
* Ethernet. Also converts uppercase hex characters into lowercase, to match
* pxelinux's behavior.
*
* @outbuf: Buffer to hold the output (must hold 22 bytes)
* @outbuf_len: Length of buffer
* Returns 1 for success, -ENOENT if 'ethaddr' is undefined in the
* environment, or some other value < 0 on error.
*/
int format_mac_pxe(char *outbuf, size_t outbuf_len);
/**
* pxe_setup_ctx() - Setup a new PXE context
*
* @ctx: Context to set up
* @cmdtp: Command table entry which started this action
* @getfile: Function to call to read a file
* @userdata: Data the caller requires for @getfile - stored in ctx->userdata
* @allow_abs_path: true to allow absolute paths
* @bootfile: Bootfile whose directory loaded files are relative to, NULL if
* none
* @return 0 if OK, -ENOMEM if out of memory
*/
int pxe_setup_ctx(struct pxe_context *ctx, struct cmd_tbl *cmdtp,
pxe_getfile_func getfile, void *userdata,
bool allow_abs_path, const char *bootfile);
/**
* pxe_destroy_ctx() - Destroy a PXE context
*
* @ctx: Context to destroy
*/
void pxe_destroy_ctx(struct pxe_context *ctx);
/**
* pxe_process() - Process a PXE file through to boot
*
* @ctx: PXE context created with pxe_setup_ctx()
* @pxefile_addr_r: Address to load file
* @prompt: Force a prompt for the user
*/
int pxe_process(struct pxe_context *ctx, ulong pxefile_addr_r, bool prompt);
#endif /* __PXE_UTILS_H */
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