blob: 8a68fa1ae34257be43aed1386968ef5a00ce7fb5 [file] [log] [blame]
/*
* Copyright 2010-2011 Calxeda, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <common.h>
#include <command.h>
#include <malloc.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <errno.h>
#include <linux/list.h>
#include "menu.h"
#define MAX_TFTP_PATH_LEN 127
/*
* Like getenv, but prints an error if envvar isn't defined in the
* environment. It always returns what getenv does, so it can be used in
* place of getenv without changing error handling otherwise.
*/
static char *from_env(char *envvar)
{
char *ret;
ret = getenv(envvar);
if (!ret)
printf("missing environment variable: %s\n", envvar);
return ret;
}
/*
* 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.
*
* Returns 1 for success, -ENOENT if 'ethaddr' is undefined in the
* environment, or some other value < 0 on error.
*/
static int format_mac_pxe(char *outbuf, size_t outbuf_len)
{
size_t ethaddr_len;
char *p, *ethaddr;
ethaddr = from_env("ethaddr");
if (!ethaddr)
return -ENOENT;
ethaddr_len = strlen(ethaddr);
/*
* ethaddr_len + 4 gives room for "01-", ethaddr, and a NUL byte at
* the end.
*/
if (outbuf_len < ethaddr_len + 4) {
printf("outbuf is too small (%d < %d)\n",
outbuf_len, ethaddr_len + 4);
return -EINVAL;
}
strcpy(outbuf, "01-");
for (p = outbuf + 3; *ethaddr; ethaddr++, p++) {
if (*ethaddr == ':')
*p = '-';
else
*p = tolower(*ethaddr);
}
*p = '\0';
return 1;
}
/*
* Returns the directory the file specified in the bootfile env variable is
* in. If bootfile isn't defined in the environment, return NULL, which should
* be interpreted as "don't prepend anything to paths".
*/
static int get_bootfile_path(char *bootfile_path, size_t bootfile_path_size)
{
char *bootfile, *last_slash;
size_t path_len;
bootfile = from_env("bootfile");
if (!bootfile) {
bootfile_path[0] = '\0';
return 1;
}
last_slash = strrchr(bootfile, '/');
if (last_slash == NULL) {
bootfile_path[0] = '\0';
return 1;
}
path_len = (last_slash - bootfile) + 1;
if (bootfile_path_size < path_len) {
printf("bootfile_path too small. (%d < %d)\n",
bootfile_path_size, path_len);
return -1;
}
strncpy(bootfile_path, bootfile, path_len);
bootfile_path[path_len] = '\0';
return 1;
}
/*
* As in pxelinux, paths to files referenced from files we retrieve are
* relative to the location of bootfile. get_relfile takes such a path and
* joins it with the bootfile path to get the full path to the target file. If
* the bootfile path is NULL, we use file_path as is.
*
* Returns 1 for success, or < 0 on error.
*/
static int get_relfile(char *file_path, void *file_addr)
{
size_t path_len;
char relfile[MAX_TFTP_PATH_LEN+1];
char addr_buf[10];
char *tftp_argv[] = {"tftp", NULL, NULL, NULL};
int err;
err = get_bootfile_path(relfile, sizeof(relfile));
if (err < 0)
return err;
path_len = strlen(file_path);
path_len += strlen(relfile);
if (path_len > MAX_TFTP_PATH_LEN) {
printf("Base path too long (%s%s)\n",
relfile,
file_path);
return -ENAMETOOLONG;
}
strcat(relfile, file_path);
printf("Retrieving file: %s\n", relfile);
sprintf(addr_buf, "%p", file_addr);
tftp_argv[1] = addr_buf;
tftp_argv[2] = relfile;
if (do_tftpb(NULL, 0, 3, tftp_argv))
return -ENOENT;
return 1;
}
/*
* 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.
*
* Returns 1 on success, or < 0 for error.
*/
static int get_pxe_file(char *file_path, void *file_addr)
{
unsigned long config_file_size;
char *tftp_filesize;
int err;
err = get_relfile(file_path, file_addr);
if (err < 0)
return err;
/*
* the file comes without a NUL byte at the end, so find out its size
* and add the NUL byte.
*/
tftp_filesize = from_env("filesize");
if (!tftp_filesize)
return -ENOENT;
if (strict_strtoul(tftp_filesize, 16, &config_file_size) < 0)
return -EINVAL;
*(char *)(file_addr + config_file_size) = '\0';
return 1;
}
#define PXELINUX_DIR "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 above.
*
* Returns 1 on success or < 0 on error.
*/
static int get_pxelinux_path(char *file, void *pxefile_addr_r)
{
size_t base_len = strlen(PXELINUX_DIR);
char path[MAX_TFTP_PATH_LEN+1];
if (base_len + strlen(file) > MAX_TFTP_PATH_LEN) {
printf("path (%s%s) too long, skipping\n",
PXELINUX_DIR, file);
return -ENAMETOOLONG;
}
sprintf(path, PXELINUX_DIR "%s", file);
return get_pxe_file(path, pxefile_addr_r);
}
/*
* Looks for a pxe file with a name based on the pxeuuid environment variable.
*
* Returns 1 on success or < 0 on error.
*/
static int pxe_uuid_path(void *pxefile_addr_r)
{
char *uuid_str;
uuid_str = from_env("pxeuuid");
if (!uuid_str)
return -ENOENT;
return get_pxelinux_path(uuid_str, pxefile_addr_r);
}
/*
* Looks for a pxe file with a name based on the 'ethaddr' environment
* variable.
*
* Returns 1 on success or < 0 on error.
*/
static int pxe_mac_path(void *pxefile_addr_r)
{
char mac_str[21];
int err;
err = format_mac_pxe(mac_str, sizeof(mac_str));
if (err < 0)
return err;
return get_pxelinux_path(mac_str, pxefile_addr_r);
}
/*
* Looks for pxe files with names based on our IP address. See pxelinux
* documentation for details on what these file names look like. We match
* that exactly.
*
* Returns 1 on success or < 0 on error.
*/
static int pxe_ipaddr_paths(void *pxefile_addr_r)
{
char ip_addr[9];
int mask_pos, err;
sprintf(ip_addr, "%08X", ntohl(NetOurIP));
for (mask_pos = 7; mask_pos >= 0; mask_pos--) {
err = get_pxelinux_path(ip_addr, pxefile_addr_r);
if (err > 0)
return err;
ip_addr[mask_pos] = '\0';
}
return -ENOENT;
}
/*
* Entry point for the 'pxe get' command.
* This Follows pxelinux's rules to download a config file from a tftp server.
* The file is stored at the location given by the pxefile_addr_r environment
* variable, which must be set.
*
* UUID comes from pxeuuid env variable, if defined
* MAC addr comes from ethaddr env variable, if defined
* IP
*
* see http://syslinux.zytor.com/wiki/index.php/PXELINUX
*
* Returns 0 on success or 1 on error.
*/
static int
do_pxe_get(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
char *pxefile_addr_str;
void *pxefile_addr_r;
int err;
if (argc != 1)
return CMD_RET_USAGE;
pxefile_addr_str = from_env("pxefile_addr_r");
if (!pxefile_addr_str)
return 1;
err = strict_strtoul(pxefile_addr_str, 16,
(unsigned long *)&pxefile_addr_r);
if (err < 0)
return 1;
/*
* Keep trying paths until we successfully get a file we're looking
* for.
*/
if (pxe_uuid_path(pxefile_addr_r) > 0
|| pxe_mac_path(pxefile_addr_r) > 0
|| pxe_ipaddr_paths(pxefile_addr_r) > 0
|| get_pxelinux_path("default", pxefile_addr_r) > 0) {
printf("Config file found\n");
return 0;
}
printf("Config file not found\n");
return 1;
}
/*
* Wrapper to make it easier to store the file at file_path in the location
* specified by envaddr_name. file_path will be joined to the bootfile path,
* if any is specified.
*
* Returns 1 on success or < 0 on error.
*/
static int get_relfile_envaddr(char *file_path, char *envaddr_name)
{
void *file_addr;
char *envaddr;
envaddr = from_env(envaddr_name);
if (!envaddr)
return -ENOENT;
if (strict_strtoul(envaddr, 16, (unsigned long *)&file_addr) < 0)
return -EINVAL;
return get_relfile(file_path, file_addr);
}
/*
* 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 *name;
char *kernel;
char *append;
char *initrd;
int attempted;
int localboot;
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.
* 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;
int timeout;
int prompt;
struct list_head labels;
};
/*
* Allocates memory for and initializes a pxe_label. This uses malloc, so the
* result must be free()'d to reclaim the memory.
*
* Returns NULL if malloc fails.
*/
static struct pxe_label *label_create(void)
{
struct pxe_label *label;
label = malloc(sizeof(struct pxe_label));
if (!label)
return NULL;
memset(label, 0, sizeof(struct pxe_label));
return label;
}
/*
* Free the memory used by a pxe_label, including that used by its name,
* kernel, append and initrd members, if they're non NULL.
*
* So - be sure to only use dynamically allocated memory for the members of
* the pxe_label struct, unless you want to clean it up first. These are
* currently only created by the pxe file parsing code.
*/
static void label_destroy(struct pxe_label *label)
{
if (label->name)
free(label->name);
if (label->kernel)
free(label->kernel);
if (label->append)
free(label->append);
if (label->initrd)
free(label->initrd);
free(label);
}
/*
* Print a label and its string members if they're defined.
*
* This is passed as a callback to the menu code for displaying each
* menu entry.
*/
static void label_print(void *data)
{
struct pxe_label *label = data;
printf("Label: %s\n", label->name);
if (label->kernel)
printf("\tkernel: %s\n", label->kernel);
if (label->append)
printf("\tappend: %s\n", label->append);
if (label->initrd)
printf("\tinitrd: %s\n", label->initrd);
}
/*
* Boot a label that specified 'localboot'. This requires that the 'localcmd'
* environment variable is defined. Its contents will be executed as U-boot
* command. If the label specified an 'append' line, its contents will be
* used to overwrite the contents of the 'bootargs' environment variable prior
* to running 'localcmd'.
*
* Returns 1 on success or < 0 on error.
*/
static int label_localboot(struct pxe_label *label)
{
char *localcmd, *dupcmd;
int ret;
localcmd = from_env("localcmd");
if (!localcmd)
return -ENOENT;
/*
* dup the command to avoid any issues with the version of it existing
* in the environment changing during the execution of the command.
*/
dupcmd = strdup(localcmd);
if (!dupcmd)
return -ENOMEM;
if (label->append)
setenv("bootargs", label->append);
printf("running: %s\n", dupcmd);
ret = run_command(dupcmd, 0);
free(dupcmd);
return ret;
}
/*
* Boot according to the contents of a pxe_label.
*
* If we can't boot for any reason, we return. A successful boot never
* returns.
*
* The kernel will be stored in the location given by the 'kernel_addr_r'
* environment variable.
*
* If the label specifies an initrd file, it will be stored in the location
* given by the 'ramdisk_addr_r' environment variable.
*
* If the label specifies an 'append' line, its contents will overwrite that
* of the 'bootargs' environment variable.
*/
static void label_boot(struct pxe_label *label)
{
char *bootm_argv[] = { "bootm", NULL, NULL, NULL, NULL };
int bootm_argc = 3;
label_print(label);
label->attempted = 1;
if (label->localboot) {
label_localboot(label);
return;
}
if (label->kernel == NULL) {
printf("No kernel given, skipping %s\n",
label->name);
return;
}
if (label->initrd) {
if (get_relfile_envaddr(label->initrd, "ramdisk_addr_r") < 0) {
printf("Skipping %s for failure retrieving initrd\n",
label->name);
return;
}
bootm_argv[2] = getenv("ramdisk_addr_r");
} else {
bootm_argv[2] = "-";
}
if (get_relfile_envaddr(label->kernel, "kernel_addr_r") < 0) {
printf("Skipping %s for failure retrieving kernel\n",
label->name);
return;
}
if (label->append)
setenv("bootargs", label->append);
bootm_argv[1] = getenv("kernel_addr_r");
/*
* fdt usage is optional. If there is an fdt_addr specified, we will
* pass it along to bootm, and adjust argc appropriately.
*/
bootm_argv[3] = getenv("fdt_addr");
if (bootm_argv[3])
bootm_argc = 4;
do_bootm(NULL, 0, bootm_argc, bootm_argv);
}
/*
* Tokens for the pxe file parser.
*/
enum token_type {
T_EOL,
T_STRING,
T_EOF,
T_MENU,
T_TITLE,
T_TIMEOUT,
T_LABEL,
T_KERNEL,
T_APPEND,
T_INITRD,
T_LOCALBOOT,
T_DEFAULT,
T_PROMPT,
T_INCLUDE,
T_INVALID
};
/*
* A token - given by a value and a type.
*/
struct token {
char *val;
enum token_type type;
};
/*
* Keywords recognized.
*/
static const struct token keywords[] = {
{"menu", T_MENU},
{"title", T_TITLE},
{"timeout", T_TIMEOUT},
{"default", T_DEFAULT},
{"prompt", T_PROMPT},
{"label", T_LABEL},
{"kernel", T_KERNEL},
{"localboot", T_LOCALBOOT},
{"append", T_APPEND},
{"initrd", T_INITRD},
{"include", T_INCLUDE},
{NULL, T_INVALID}
};
/*
* Since pxe(linux) files don't have a token to identify the start of a
* literal, we have to keep track of when we're in a state where a literal is
* expected vs when we're in a state a keyword is expected.
*/
enum lex_state {
L_NORMAL = 0,
L_KEYWORD,
L_SLITERAL
};
/*
* get_string retrieves a string from *p and stores it as a token in
* *t.
*
* get_string used for scanning both string literals and keywords.
*
* Characters from *p are copied into t-val until a character equal to
* delim is found, or a NUL byte is reached. If delim has the special value of
* ' ', any whitespace character will be used as a delimiter.
*
* If lower is unequal to 0, uppercase characters will be converted to
* lowercase in the result. This is useful to make keywords case
* insensitive.
*
* The location of *p is updated to point to the first character after the end
* of the token - the ending delimiter.
*
* On success, the new value of t->val is returned. Memory for t->val is
* allocated using malloc and must be free()'d to reclaim it. If insufficient
* memory is available, NULL is returned.
*/
static char *get_string(char **p, struct token *t, char delim, int lower)
{
char *b, *e;
size_t len, i;
/*
* b and e both start at the beginning of the input stream.
*
* e is incremented until we find the ending delimiter, or a NUL byte
* is reached. Then, we take e - b to find the length of the token.
*/
b = e = *p;
while (*e) {
if ((delim == ' ' && isspace(*e)) || delim == *e)
break;
e++;
}
len = e - b;
/*
* Allocate memory to hold the string, and copy it in, converting
* characters to lowercase if lower is != 0.
*/
t->val = malloc(len + 1);
if (!t->val)
return NULL;
for (i = 0; i < len; i++, b++) {
if (lower)
t->val[i] = tolower(*b);
else
t->val[i] = *b;
}
t->val[len] = '\0';
/*
* Update *p so the caller knows where to continue scanning.
*/
*p = e;
t->type = T_STRING;
return t->val;
}
/*
* Populate a keyword token with a type and value.
*/
static void get_keyword(struct token *t)
{
int i;
for (i = 0; keywords[i].val; i++) {
if (!strcmp(t->val, keywords[i].val)) {
t->type = keywords[i].type;
break;
}
}
}
/*
* Get the next token. We have to keep track of which state we're in to know
* if we're looking to get a string literal or a keyword.
*
* *p is updated to point at the first character after the current token.
*/
static void get_token(char **p, struct token *t, enum lex_state state)
{
char *c = *p;
t->type = T_INVALID;
/* eat non EOL whitespace */
while (isblank(*c))
c++;
/*
* eat comments. note that string literals can't begin with #, but
* can contain a # after their first character.
*/
if (*c == '#') {
while (*c && *c != '\n')
c++;
}
if (*c == '\n') {
t->type = T_EOL;
c++;
} else if (*c == '\0') {
t->type = T_EOF;
c++;
} else if (state == L_SLITERAL) {
get_string(&c, t, '\n', 0);
} else if (state == L_KEYWORD) {
/*
* when we expect a keyword, we first get the next string
* token delimited by whitespace, and then check if it
* matches a keyword in our keyword list. if it does, it's
* converted to a keyword token of the appropriate type, and
* if not, it remains a string token.
*/
get_string(&c, t, ' ', 1);
get_keyword(t);
}
*p = c;
}
/*
* Increment *c until we get to the end of the current line, or EOF.
*/
static void eol_or_eof(char **c)
{
while (**c && **c != '\n')
(*c)++;
}
/*
* All of these parse_* functions share some common behavior.
*
* They finish with *c pointing after the token they parse, and return 1 on
* success, or < 0 on error.
*/
/*
* Parse a string literal and store a pointer it at *dst. String literals
* terminate at the end of the line.
*/
static int parse_sliteral(char **c, char **dst)
{
struct token t;
char *s = *c;
get_token(c, &t, L_SLITERAL);
if (t.type != T_STRING) {
printf("Expected string literal: %.*s\n", (int)(*c - s), s);
return -EINVAL;
}
*dst = t.val;
return 1;
}
/*
* Parse a base 10 (unsigned) integer and store it at *dst.
*/
static int parse_integer(char **c, int *dst)
{
struct token t;
char *s = *c;
unsigned long temp;
get_token(c, &t, L_SLITERAL);
if (t.type != T_STRING) {
printf("Expected string: %.*s\n", (int)(*c - s), s);
return -EINVAL;
}
if (strict_strtoul(t.val, 10, &temp) < 0) {
printf("Expected unsigned integer: %s\n", t.val);
return -EINVAL;
}
*dst = (int)temp;
free(t.val);
return 1;
}
static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level);
/*
* Parse an include statement, and retrieve and parse the file it mentions.
*
* base should point to a location where it's safe to store the file, and
* nest_level should indicate how many nested includes have occurred. For this
* include, nest_level has already been incremented and doesn't need to be
* incremented here.
*/
static int handle_include(char **c, char *base,
struct pxe_menu *cfg, int nest_level)
{
char *include_path;
char *s = *c;
int err;
err = parse_sliteral(c, &include_path);
if (err < 0) {
printf("Expected include path: %.*s\n",
(int)(*c - s), s);
return err;
}
err = get_pxe_file(include_path, base);
if (err < 0) {
printf("Couldn't retrieve %s\n", include_path);
return err;
}
return parse_pxefile_top(base, cfg, nest_level);
}
/*
* Parse lines that begin with 'menu'.
*
* b and nest are provided to handle the 'menu include' case.
*
* b should be the address where the file currently being parsed is stored.
*
* nest_level should be 1 when parsing the top level pxe file, 2 when parsing
* a file it includes, 3 when parsing a file included by that file, and so on.
*/
static int parse_menu(char **c, struct pxe_menu *cfg, char *b, int nest_level)
{
struct token t;
char *s = *c;
int err = 0;
get_token(c, &t, L_KEYWORD);
switch (t.type) {
case T_TITLE:
err = parse_sliteral(c, &cfg->title);
break;
case T_INCLUDE:
err = handle_include(c, b + strlen(b) + 1, cfg,
nest_level + 1);
break;
default:
printf("Ignoring malformed menu command: %.*s\n",
(int)(*c - s), s);
}
if (err < 0)
return err;
eol_or_eof(c);
return 1;
}
/*
* Handles parsing a 'menu line' when we're parsing a label.
*/
static int parse_label_menu(char **c, struct pxe_menu *cfg,
struct pxe_label *label)
{
struct token t;
char *s;
s = *c;
get_token(c, &t, L_KEYWORD);
switch (t.type) {
case T_DEFAULT:
if (cfg->default_label)
free(cfg->default_label);
cfg->default_label = strdup(label->name);
if (!cfg->default_label)
return -ENOMEM;
break;
default:
printf("Ignoring malformed menu command: %.*s\n",
(int)(*c - s), s);
}
eol_or_eof(c);
return 0;
}
/*
* Parses a label and adds it to the list of labels for a menu.
*
* A label ends when we either get to the end of a file, or
* get some input we otherwise don't have a handler defined
* for.
*
*/
static int parse_label(char **c, struct pxe_menu *cfg)
{
struct token t;
char *s = *c;
struct pxe_label *label;
int err;
label = label_create();
if (!label)
return -ENOMEM;
err = parse_sliteral(c, &label->name);
if (err < 0) {
printf("Expected label name: %.*s\n", (int)(*c - s), s);
label_destroy(label);
return -EINVAL;
}
list_add_tail(&label->list, &cfg->labels);
while (1) {
s = *c;
get_token(c, &t, L_KEYWORD);
err = 0;
switch (t.type) {
case T_MENU:
err = parse_label_menu(c, cfg, label);
break;
case T_KERNEL:
err = parse_sliteral(c, &label->kernel);
break;
case T_APPEND:
err = parse_sliteral(c, &label->append);
break;
case T_INITRD:
err = parse_sliteral(c, &label->initrd);
break;
case T_LOCALBOOT:
err = parse_integer(c, &label->localboot);
break;
case T_EOL:
break;
default:
/*
* put the token back! we don't want it - it's the end
* of a label and whatever token this is, it's
* something for the menu level context to handle.
*/
*c = s;
return 1;
}
if (err < 0)
return err;
}
}
/*
* This 16 comes from the limit pxelinux imposes on nested includes.
*
* There is no reason at all we couldn't do more, but some limit helps prevent
* infinite (until crash occurs) recursion if a file tries to include itself.
*/
#define MAX_NEST_LEVEL 16
/*
* Entry point for parsing a menu file. nest_level indicates how many times
* we've nested in includes. It will be 1 for the top level menu file.
*
* Returns 1 on success, < 0 on error.
*/
static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level)
{
struct token t;
char *s, *b, *label_name;
int err;
b = p;
if (nest_level > MAX_NEST_LEVEL) {
printf("Maximum nesting (%d) exceeded\n", MAX_NEST_LEVEL);
return -EMLINK;
}
while (1) {
s = p;
get_token(&p, &t, L_KEYWORD);
err = 0;
switch (t.type) {
case T_MENU:
err = parse_menu(&p, cfg, b, nest_level);
break;
case T_TIMEOUT:
err = parse_integer(&p, &cfg->timeout);
break;
case T_LABEL:
err = parse_label(&p, cfg);
break;
case T_DEFAULT:
err = parse_sliteral(&p, &label_name);
if (label_name) {
if (cfg->default_label)
free(cfg->default_label);
cfg->default_label = label_name;
}
break;
case T_PROMPT:
err = parse_integer(&p, &cfg->prompt);
break;
case T_EOL:
break;
case T_EOF:
return 1;
default:
printf("Ignoring unknown command: %.*s\n",
(int)(p - s), s);
eol_or_eof(&p);
}
if (err < 0)
return err;
}
}
/*
* Free the memory used by a pxe_menu and its labels.
*/
static void destroy_pxe_menu(struct pxe_menu *cfg)
{
struct list_head *pos, *n;
struct pxe_label *label;
if (cfg->title)
free(cfg->title);
if (cfg->default_label)
free(cfg->default_label);
list_for_each_safe(pos, n, &cfg->labels) {
label = list_entry(pos, struct pxe_label, list);
label_destroy(label);
}
free(cfg);
}
/*
* Entry point for parsing a pxe file. This is only used for the top level
* file.
*
* 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.
*/
static struct pxe_menu *parse_pxefile(char *menucfg)
{
struct pxe_menu *cfg;
cfg = malloc(sizeof(struct pxe_menu));
if (!cfg)
return NULL;
memset(cfg, 0, sizeof(struct pxe_menu));
INIT_LIST_HEAD(&cfg->labels);
if (parse_pxefile_top(menucfg, cfg, 1) < 0) {
destroy_pxe_menu(cfg);
return NULL;
}
return cfg;
}
/*
* Converts a pxe_menu struct into a menu struct for use with U-boot's generic
* menu code.
*/
static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg)
{
struct pxe_label *label;
struct list_head *pos;
struct menu *m;
int err;
/*
* Create a menu and add items for all the labels.
*/
m = menu_create(cfg->title, cfg->timeout, cfg->prompt, label_print);
if (!m)
return NULL;
list_for_each(pos, &cfg->labels) {
label = list_entry(pos, struct pxe_label, list);
if (menu_item_add(m, label->name, label) != 1) {
menu_destroy(m);
return NULL;
}
}
/*
* After we've created items for each label in the menu, set the
* menu's default label if one was specified.
*/
if (cfg->default_label) {
err = menu_default_set(m, cfg->default_label);
if (err != 1) {
if (err != -ENOENT) {
menu_destroy(m);
return NULL;
}
printf("Missing default: %s\n", cfg->default_label);
}
}
return m;
}
/*
* Try to boot any labels we have yet to attempt to boot.
*/
static void boot_unattempted_labels(struct pxe_menu *cfg)
{
struct list_head *pos;
struct pxe_label *label;
list_for_each(pos, &cfg->labels) {
label = list_entry(pos, struct pxe_label, list);
if (!label->attempted)
label_boot(label);
}
}
/*
* 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.
*/
static void handle_pxe_menu(struct pxe_menu *cfg)
{
void *choice;
struct menu *m;
int err;
m = pxe_menu_to_menu(cfg);
if (!m)
return;
err = menu_get_choice(m, &choice);
menu_destroy(m);
/*
* err == 1 means we got a choice back from menu_get_choice.
*
* err == -ENOENT if the menu was setup to select the default but no
* default was set. in that case, we should continue trying to boot
* labels that haven't been attempted yet.
*
* otherwise, the user interrupted or there was some other error and
* we give up.
*/
if (err == 1)
label_boot(choice);
else if (err != -ENOENT)
return;
boot_unattempted_labels(cfg);
}
/*
* Boots a system using a pxe file
*
* Returns 0 on success, 1 on error.
*/
static int
do_pxe_boot(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
unsigned long pxefile_addr_r;
struct pxe_menu *cfg;
char *pxefile_addr_str;
if (argc == 1) {
pxefile_addr_str = from_env("pxefile_addr_r");
if (!pxefile_addr_str)
return 1;
} else if (argc == 2) {
pxefile_addr_str = argv[1];
} else {
return CMD_RET_USAGE;
}
if (strict_strtoul(pxefile_addr_str, 16, &pxefile_addr_r) < 0) {
printf("Invalid pxefile address: %s\n", pxefile_addr_str);
return 1;
}
cfg = parse_pxefile((char *)(pxefile_addr_r));
if (cfg == NULL) {
printf("Error parsing config file\n");
return 1;
}
handle_pxe_menu(cfg);
destroy_pxe_menu(cfg);
return 0;
}
static cmd_tbl_t cmd_pxe_sub[] = {
U_BOOT_CMD_MKENT(get, 1, 1, do_pxe_get, "", ""),
U_BOOT_CMD_MKENT(boot, 2, 1, do_pxe_boot, "", "")
};
int do_pxe(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
cmd_tbl_t *cp;
if (argc < 2)
return CMD_RET_USAGE;
/* drop initial "pxe" arg */
argc--;
argv++;
cp = find_cmd_tbl(argv[0], cmd_pxe_sub, ARRAY_SIZE(cmd_pxe_sub));
if (cp)
return cp->cmd(cmdtp, flag, argc, argv);
return CMD_RET_USAGE;
}
U_BOOT_CMD(
pxe, 3, 1, do_pxe,
"commands to get and boot from pxe files",
"get - try to retrieve a pxe file using tftp\npxe "
"boot [pxefile_addr_r] - boot from the pxe file at pxefile_addr_r\n"
);