From 262cfb5b15420a1aea465745a821e684b3dfa153 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:00 -0600 Subject: pxe: Move pxe_utils files Move the header file into the main include/ directory so we can use it from the bootmethod code. Move the C file into boot/ since it relates to booting. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 205 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 205 insertions(+) create mode 100644 include/pxe_utils.h (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h new file mode 100644 index 00000000000..6681442ea55 --- /dev/null +++ b/include/pxe_utils.h @@ -0,0 +1,205 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef __PXE_UTILS_H +#define __PXE_UTILS_H + +#include + +/* + * 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 + */ +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; +}; + +/** + * 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 + */ +void pxe_setup_ctx(struct pxe_context *ctx, struct cmd_tbl *cmdtp, + pxe_getfile_func getfile, void *userdata, + bool allow_abs_path); + +#endif /* __PXE_UTILS_H */ -- cgit v1.2.3 From 9e62e7ca543ea94a46f30053262f67202e2435f4 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:03 -0600 Subject: pxe: Move common parsing coding into pxe_util Both the syslinux and pxe commands use essentially the same code to parse and run extlinux.conf files. Move this into a common function. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 6681442ea55..0cae0dabec3 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -202,4 +202,13 @@ void pxe_setup_ctx(struct pxe_context *ctx, struct cmd_tbl *cmdtp, pxe_getfile_func getfile, void *userdata, bool allow_abs_path); +/** + * 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 */ -- cgit v1.2.3 From 12df842ee324a7e188a643bfee6fe08f28127b26 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:04 -0600 Subject: pxe: Clean up the use of bootfile The 'bootfile' environment variable is read in the bowels of pxe_util to provide a directory to which all loaded files are relative. This is not obvious from the API to PXE and it is strange to make the caller set an environment variable rather than pass this as a parameter. The code is also convoluted, which this feature implemented by get_bootfile_path(). Update the API to improve this. Unfortunately this means that pxe_setup_ctx() can fail, so add error checking. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 0cae0dabec3..543d0245c8a 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -86,6 +86,8 @@ typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path, * @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; @@ -102,6 +104,7 @@ struct pxe_context { void *userdata; bool allow_abs_path; + char *bootdir; }; /** @@ -197,10 +200,20 @@ int format_mac_pxe(char *outbuf, size_t outbuf_len); * @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 */ -void pxe_setup_ctx(struct pxe_context *ctx, struct cmd_tbl *cmdtp, - pxe_getfile_func getfile, void *userdata, - bool allow_abs_path); +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 -- cgit v1.2.3 From 74b7a2b8815cf953ea0b72800bd9db7f0d6a119a Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:05 -0600 Subject: pxe: Drop get_bootfile_path() This function no longer makes sense, since it is pretty easy to prepend the boot directory to the filename. Drop it and update its only caller. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 543d0245c8a..8b50f2e6861 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -202,7 +202,8 @@ int format_mac_pxe(char *outbuf, size_t outbuf_len); * @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 + * @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, -- cgit v1.2.3 From 4d79e884adf6842beb94566bf5249c07a84a5b51 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:08 -0600 Subject: pxe: Return the file size from the getfile() function It is pretty strange that the pxe code uses the 'filesize' environment variable find the size of a file it has just read. Partly this is because it uses the command-line interpreter to parse its request to load the file. As a first step towards unwinding this, return it directly from the getfile() function. This makes the code a bit longer, for now, but will be cleaned up in future patches. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 8b50f2e6861..194a5ed8cc7 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -77,7 +77,7 @@ struct pxe_menu { struct pxe_context; typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path, - char *file_addr); + char *file_addr, ulong *filesizep); /** * struct pxe_context - context information for PXE parsing @@ -88,6 +88,7 @@ typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path, * @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; @@ -98,6 +99,7 @@ struct 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; @@ -105,6 +107,7 @@ struct pxe_context { void *userdata; bool allow_abs_path; char *bootdir; + ulong pxe_file_size; }; /** @@ -225,4 +228,12 @@ void pxe_destroy_ctx(struct pxe_context *ctx); */ 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); + #endif /* __PXE_UTILS_H */ -- cgit v1.2.3 From d50244e9d8583378770392fb429a0283b2b47885 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 14 Oct 2021 12:48:11 -0600 Subject: pxe: Allow calling the pxe_get logic directly Refactor this code so that we can call the 'pxe get' command without going through the command-line interpreter. This makes it easier to get the information we need, without going through environment variables. Signed-off-by: Simon Glass Reviewed-by: Artem Lapkin Tested-by: Artem Lapkin Reviewed-by: Ramon Fried --- include/pxe_utils.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include/pxe_utils.h') diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 194a5ed8cc7..b7037f841a6 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -236,4 +236,18 @@ int pxe_process(struct pxe_context *ctx, ulong pxefile_addr_r, bool prompt); */ 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 */ -- cgit v1.2.3