123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255 |
- /* 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.
- * kaslrseed - 1 if generate kaslrseed from hw_rng
- * 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;
- int kaslrseed;
- 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, ulong *filesizep);
- /**
- * 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
- * @pxe_file_size: Size of the PXE file
- */
- 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
- * @filesizep: Returns the file size in bytes
- * Return 0 if OK, -ve on error
- */
- pxe_getfile_func getfile;
- void *userdata;
- bool allow_abs_path;
- char *bootdir;
- ulong pxe_file_size;
- };
- /**
- * 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, -E2BIG if bootfile is larger than
- * MAX_TFTP_PATH_LEN bytes
- */
- 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);
- /**
- * pxe_get_file_size() - Read the value of the 'filesize' environment variable
- *
- * @sizep: Place to put the value
- * Return: 0 if OK, -ENOENT if no such variable, -EINVAL if format is invalid
- */
- int pxe_get_file_size(ulong *sizep);
- /**
- * pxe_get() - Get the PXE file from the server
- *
- * This tries various filenames to obtain a PXE file
- *
- * @pxefile_addr_r: Address to put file
- * @bootdirp: Returns the boot filename, or NULL if none. This is the 'bootfile'
- * option provided by the DHCP server. If none, returns NULL. For example,
- * "rpi/info", which indicates that all files should be fetched from the
- * "rpi/" subdirectory
- * @sizep: Size of the PXE file (not bootfile)
- */
- int pxe_get(ulong pxefile_addr_r, char **bootdirp, ulong *sizep);
- #endif /* __PXE_UTILS_H */
|