blob: 3efd7008e95fe1d74bb48e16a7969e6eec700f22 [file] [log] [blame]
Jason Hobbs06283a62011-08-31 10:37:30 -05001/*
2 * Copyright 2010-2011 Calxeda, Inc.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
7 * any later version.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17#include <common.h>
18#include <command.h>
19#include <malloc.h>
20#include <linux/string.h>
21#include <linux/ctype.h>
22#include <errno.h>
23#include <linux/list.h>
24
25#include "menu.h"
26
27#define MAX_TFTP_PATH_LEN 127
28
29
30/*
31 * Like getenv, but prints an error if envvar isn't defined in the
32 * environment. It always returns what getenv does, so it can be used in
33 * place of getenv without changing error handling otherwise.
34 */
35static char *from_env(char *envvar)
36{
37 char *ret;
38
39 ret = getenv(envvar);
40
41 if (!ret)
42 printf("missing environment variable: %s\n", envvar);
43
44 return ret;
45}
46
47/*
48 * Convert an ethaddr from the environment to the format used by pxelinux
49 * filenames based on mac addresses. Convert's ':' to '-', and adds "01-" to
50 * the beginning of the ethernet address to indicate a hardware type of
51 * Ethernet. Also converts uppercase hex characters into lowercase, to match
52 * pxelinux's behavior.
53 *
54 * Returns 1 for success, -ENOENT if 'ethaddr' is undefined in the
55 * environment, or some other value < 0 on error.
56 */
57static int format_mac_pxe(char *outbuf, size_t outbuf_len)
58{
59 size_t ethaddr_len;
60 char *p, *ethaddr;
61
62 ethaddr = from_env("ethaddr");
63
64 if (!ethaddr)
65 return -ENOENT;
66
67 ethaddr_len = strlen(ethaddr);
68
69 /*
70 * ethaddr_len + 4 gives room for "01-", ethaddr, and a NUL byte at
71 * the end.
72 */
73 if (outbuf_len < ethaddr_len + 4) {
74 printf("outbuf is too small (%d < %d)\n",
75 outbuf_len, ethaddr_len + 4);
76
77 return -EINVAL;
78 }
79
80 strcpy(outbuf, "01-");
81
82 for (p = outbuf + 3; *ethaddr; ethaddr++, p++) {
83 if (*ethaddr == ':')
84 *p = '-';
85 else
86 *p = tolower(*ethaddr);
87 }
88
89 *p = '\0';
90
91 return 1;
92}
93
94/*
95 * Returns the directory the file specified in the bootfile env variable is
96 * in. If bootfile isn't defined in the environment, return NULL, which should
97 * be interpreted as "don't prepend anything to paths".
98 */
99static int get_bootfile_path(char *bootfile_path, size_t bootfile_path_size)
100{
101 char *bootfile, *last_slash;
102 size_t path_len;
103
104 bootfile = from_env("bootfile");
105
106 if (!bootfile) {
107 bootfile_path[0] = '\0';
108 return 1;
109 }
110
111 last_slash = strrchr(bootfile, '/');
112
113 if (last_slash == NULL) {
114 bootfile_path[0] = '\0';
115 return 1;
116 }
117
118 path_len = (last_slash - bootfile) + 1;
119
120 if (bootfile_path_size < path_len) {
121 printf("bootfile_path too small. (%d < %d)\n",
122 bootfile_path_size, path_len);
123
124 return -1;
125 }
126
127 strncpy(bootfile_path, bootfile, path_len);
128
129 bootfile_path[path_len] = '\0';
130
131 return 1;
132}
133
134/*
135 * As in pxelinux, paths to files referenced from files we retrieve are
136 * relative to the location of bootfile. get_relfile takes such a path and
137 * joins it with the bootfile path to get the full path to the target file. If
138 * the bootfile path is NULL, we use file_path as is.
139 *
140 * Returns 1 for success, or < 0 on error.
141 */
142static int get_relfile(char *file_path, void *file_addr)
143{
144 size_t path_len;
145 char relfile[MAX_TFTP_PATH_LEN+1];
146 char addr_buf[10];
147 char *tftp_argv[] = {"tftp", NULL, NULL, NULL};
148 int err;
149
150 err = get_bootfile_path(relfile, sizeof(relfile));
151
152 if (err < 0)
153 return err;
154
155 path_len = strlen(file_path);
156 path_len += strlen(relfile);
157
158 if (path_len > MAX_TFTP_PATH_LEN) {
159 printf("Base path too long (%s%s)\n",
160 relfile,
161 file_path);
162
163 return -ENAMETOOLONG;
164 }
165
166 strcat(relfile, file_path);
167
168 printf("Retrieving file: %s\n", relfile);
169
170 sprintf(addr_buf, "%p", file_addr);
171
172 tftp_argv[1] = addr_buf;
173 tftp_argv[2] = relfile;
174
175 if (do_tftpb(NULL, 0, 3, tftp_argv))
176 return -ENOENT;
177
178 return 1;
179}
180
181/*
182 * Retrieve the file at 'file_path' to the locate given by 'file_addr'. If
183 * 'bootfile' was specified in the environment, the path to bootfile will be
184 * prepended to 'file_path' and the resulting path will be used.
185 *
186 * Returns 1 on success, or < 0 for error.
187 */
188static int get_pxe_file(char *file_path, void *file_addr)
189{
190 unsigned long config_file_size;
191 char *tftp_filesize;
192 int err;
193
194 err = get_relfile(file_path, file_addr);
195
196 if (err < 0)
197 return err;
198
199 /*
200 * the file comes without a NUL byte at the end, so find out its size
201 * and add the NUL byte.
202 */
203 tftp_filesize = from_env("filesize");
204
205 if (!tftp_filesize)
206 return -ENOENT;
207
208 if (strict_strtoul(tftp_filesize, 16, &config_file_size) < 0)
209 return -EINVAL;
210
211 *(char *)(file_addr + config_file_size) = '\0';
212
213 return 1;
214}
215
216#define PXELINUX_DIR "pxelinux.cfg/"
217
218/*
219 * Retrieves a file in the 'pxelinux.cfg' folder. Since this uses get_pxe_file
220 * to do the hard work, the location of the 'pxelinux.cfg' folder is generated
221 * from the bootfile path, as described above.
222 *
223 * Returns 1 on success or < 0 on error.
224 */
225static int get_pxelinux_path(char *file, void *pxefile_addr_r)
226{
227 size_t base_len = strlen(PXELINUX_DIR);
228 char path[MAX_TFTP_PATH_LEN+1];
229
230 if (base_len + strlen(file) > MAX_TFTP_PATH_LEN) {
231 printf("path (%s%s) too long, skipping\n",
232 PXELINUX_DIR, file);
233 return -ENAMETOOLONG;
234 }
235
236 sprintf(path, PXELINUX_DIR "%s", file);
237
238 return get_pxe_file(path, pxefile_addr_r);
239}
240
241/*
242 * Looks for a pxe file with a name based on the pxeuuid environment variable.
243 *
244 * Returns 1 on success or < 0 on error.
245 */
246static int pxe_uuid_path(void *pxefile_addr_r)
247{
248 char *uuid_str;
249
250 uuid_str = from_env("pxeuuid");
251
252 if (!uuid_str)
253 return -ENOENT;
254
255 return get_pxelinux_path(uuid_str, pxefile_addr_r);
256}
257
258/*
259 * Looks for a pxe file with a name based on the 'ethaddr' environment
260 * variable.
261 *
262 * Returns 1 on success or < 0 on error.
263 */
264static int pxe_mac_path(void *pxefile_addr_r)
265{
266 char mac_str[21];
267 int err;
268
269 err = format_mac_pxe(mac_str, sizeof(mac_str));
270
271 if (err < 0)
272 return err;
273
274 return get_pxelinux_path(mac_str, pxefile_addr_r);
275}
276
277/*
278 * Looks for pxe files with names based on our IP address. See pxelinux
279 * documentation for details on what these file names look like. We match
280 * that exactly.
281 *
282 * Returns 1 on success or < 0 on error.
283 */
284static int pxe_ipaddr_paths(void *pxefile_addr_r)
285{
286 char ip_addr[9];
287 int mask_pos, err;
288
289 sprintf(ip_addr, "%08X", ntohl(NetOurIP));
290
291 for (mask_pos = 7; mask_pos >= 0; mask_pos--) {
292 err = get_pxelinux_path(ip_addr, pxefile_addr_r);
293
294 if (err > 0)
295 return err;
296
297 ip_addr[mask_pos] = '\0';
298 }
299
300 return -ENOENT;
301}
302
303/*
304 * Entry point for the 'pxe get' command.
305 * This Follows pxelinux's rules to download a config file from a tftp server.
306 * The file is stored at the location given by the pxefile_addr_r environment
307 * variable, which must be set.
308 *
309 * UUID comes from pxeuuid env variable, if defined
310 * MAC addr comes from ethaddr env variable, if defined
311 * IP
312 *
313 * see http://syslinux.zytor.com/wiki/index.php/PXELINUX
314 *
315 * Returns 0 on success or 1 on error.
316 */
317static int
318do_pxe_get(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
319{
320 char *pxefile_addr_str;
321 void *pxefile_addr_r;
322 int err;
323
324 if (argc != 1)
325 return cmd_usage(cmdtp);
326
327
328 pxefile_addr_str = from_env("pxefile_addr_r");
329
330 if (!pxefile_addr_str)
331 return 1;
332
333 err = strict_strtoul(pxefile_addr_str, 16,
334 (unsigned long *)&pxefile_addr_r);
335 if (err < 0)
336 return 1;
337
338 /*
339 * Keep trying paths until we successfully get a file we're looking
340 * for.
341 */
342 if (pxe_uuid_path(pxefile_addr_r) > 0
343 || pxe_mac_path(pxefile_addr_r) > 0
344 || pxe_ipaddr_paths(pxefile_addr_r) > 0
345 || get_pxelinux_path("default", pxefile_addr_r) > 0) {
346
347 printf("Config file found\n");
348
349 return 0;
350 }
351
352 printf("Config file not found\n");
353
354 return 1;
355}
356
357/*
358 * Wrapper to make it easier to store the file at file_path in the location
359 * specified by envaddr_name. file_path will be joined to the bootfile path,
360 * if any is specified.
361 *
362 * Returns 1 on success or < 0 on error.
363 */
364static int get_relfile_envaddr(char *file_path, char *envaddr_name)
365{
366 void *file_addr;
367 char *envaddr;
368
369 envaddr = from_env(envaddr_name);
370
371 if (!envaddr)
372 return -ENOENT;
373
374 if (strict_strtoul(envaddr, 16, (unsigned long *)&file_addr) < 0)
375 return -EINVAL;
376
377 return get_relfile(file_path, file_addr);
378}
379
380/*
381 * A note on the pxe file parser.
382 *
383 * We're parsing files that use syslinux grammar, which has a few quirks.
384 * String literals must be recognized based on context - there is no
385 * quoting or escaping support. There's also nothing to explicitly indicate
386 * when a label section completes. We deal with that by ending a label
387 * section whenever we see a line that doesn't include.
388 *
389 * As with the syslinux family, this same file format could be reused in the
390 * future for non pxe purposes. The only action it takes during parsing that
391 * would throw this off is handling of include files. It assumes we're using
392 * pxe, and does a tftp download of a file listed as an include file in the
393 * middle of the parsing operation. That could be handled by refactoring it to
394 * take a 'include file getter' function.
395 */
396
397/*
398 * Describes a single label given in a pxe file.
399 *
400 * Create these with the 'label_create' function given below.
401 *
402 * name - the name of the menu as given on the 'menu label' line.
403 * kernel - the path to the kernel file to use for this label.
404 * append - kernel command line to use when booting this label
405 * initrd - path to the initrd to use for this label.
406 * attempted - 0 if we haven't tried to boot this label, 1 if we have.
407 * localboot - 1 if this label specified 'localboot', 0 otherwise.
408 * list - lets these form a list, which a pxe_menu struct will hold.
409 */
410struct pxe_label {
411 char *name;
412 char *kernel;
413 char *append;
414 char *initrd;
415 int attempted;
416 int localboot;
417 struct list_head list;
418};
419
420/*
421 * Describes a pxe menu as given via pxe files.
422 *
423 * title - the name of the menu as given by a 'menu title' line.
424 * default_label - the name of the default label, if any.
425 * timeout - time in tenths of a second to wait for a user key-press before
426 * booting the default label.
427 * prompt - if 0, don't prompt for a choice unless the timeout period is
428 * interrupted. If 1, always prompt for a choice regardless of
429 * timeout.
430 * labels - a list of labels defined for the menu.
431 */
432struct pxe_menu {
433 char *title;
434 char *default_label;
435 int timeout;
436 int prompt;
437 struct list_head labels;
438};
439
440/*
441 * Allocates memory for and initializes a pxe_label. This uses malloc, so the
442 * result must be free()'d to reclaim the memory.
443 *
444 * Returns NULL if malloc fails.
445 */
446static struct pxe_label *label_create(void)
447{
448 struct pxe_label *label;
449
450 label = malloc(sizeof(struct pxe_label));
451
452 if (!label)
453 return NULL;
454
455 memset(label, 0, sizeof(struct pxe_label));
456
457 return label;
458}
459
460/*
461 * Free the memory used by a pxe_label, including that used by its name,
462 * kernel, append and initrd members, if they're non NULL.
463 *
464 * So - be sure to only use dynamically allocated memory for the members of
465 * the pxe_label struct, unless you want to clean it up first. These are
466 * currently only created by the pxe file parsing code.
467 */
468static void label_destroy(struct pxe_label *label)
469{
470 if (label->name)
471 free(label->name);
472
473 if (label->kernel)
474 free(label->kernel);
475
476 if (label->append)
477 free(label->append);
478
479 if (label->initrd)
480 free(label->initrd);
481
482 free(label);
483}
484
485/*
486 * Print a label and its string members if they're defined.
487 *
488 * This is passed as a callback to the menu code for displaying each
489 * menu entry.
490 */
491static void label_print(void *data)
492{
493 struct pxe_label *label = data;
494
495 printf("Label: %s\n", label->name);
496
497 if (label->kernel)
498 printf("\tkernel: %s\n", label->kernel);
499
500 if (label->append)
501 printf("\tappend: %s\n", label->append);
502
503 if (label->initrd)
504 printf("\tinitrd: %s\n", label->initrd);
505}
506
507/*
508 * Boot a label that specified 'localboot'. This requires that the 'localcmd'
509 * environment variable is defined. Its contents will be executed as U-boot
510 * command. If the label specified an 'append' line, its contents will be
511 * used to overwrite the contents of the 'bootargs' environment variable prior
512 * to running 'localcmd'.
513 *
514 * Returns 1 on success or < 0 on error.
515 */
516static int label_localboot(struct pxe_label *label)
517{
518 char *localcmd, *dupcmd;
519 int ret;
520
521 localcmd = from_env("localcmd");
522
523 if (!localcmd)
524 return -ENOENT;
525
526 /*
527 * dup the command to avoid any issues with the version of it existing
528 * in the environment changing during the execution of the command.
529 */
530 dupcmd = strdup(localcmd);
531
532 if (!dupcmd)
533 return -ENOMEM;
534
535 if (label->append)
536 setenv("bootargs", label->append);
537
538 printf("running: %s\n", dupcmd);
539
540 ret = run_command2(dupcmd, 0);
541
542 free(dupcmd);
543
544 return ret;
545}
546
547/*
548 * Boot according to the contents of a pxe_label.
549 *
550 * If we can't boot for any reason, we return. A successful boot never
551 * returns.
552 *
553 * The kernel will be stored in the location given by the 'kernel_addr_r'
554 * environment variable.
555 *
556 * If the label specifies an initrd file, it will be stored in the location
557 * given by the 'ramdisk_addr_r' environment variable.
558 *
559 * If the label specifies an 'append' line, its contents will overwrite that
560 * of the 'bootargs' environment variable.
561 */
562static void label_boot(struct pxe_label *label)
563{
564 char *bootm_argv[] = { "bootm", NULL, NULL, NULL, NULL };
565 int bootm_argc = 3;
566
567 label_print(label);
568
569 label->attempted = 1;
570
571 if (label->localboot) {
572 label_localboot(label);
573 return;
574 }
575
576 if (label->kernel == NULL) {
577 printf("No kernel given, skipping %s\n",
578 label->name);
579 return;
580 }
581
582 if (label->initrd) {
583 if (get_relfile_envaddr(label->initrd, "ramdisk_addr_r") < 0) {
584 printf("Skipping %s for failure retrieving initrd\n",
585 label->name);
586 return;
587 }
588
589 bootm_argv[2] = getenv("ramdisk_addr_r");
590 } else {
591 bootm_argv[2] = "-";
592 }
593
594 if (get_relfile_envaddr(label->kernel, "kernel_addr_r") < 0) {
595 printf("Skipping %s for failure retrieving kernel\n",
596 label->name);
597 return;
598 }
599
600 if (label->append)
601 setenv("bootargs", label->append);
602
603 bootm_argv[1] = getenv("kernel_addr_r");
604
605 /*
606 * fdt usage is optional. If there is an fdt_addr specified, we will
607 * pass it along to bootm, and adjust argc appropriately.
608 */
609 bootm_argv[3] = getenv("fdt_addr");
610
611 if (bootm_argv[3])
612 bootm_argc = 4;
613
614 do_bootm(NULL, 0, bootm_argc, bootm_argv);
615}
616
617/*
618 * Tokens for the pxe file parser.
619 */
620enum token_type {
621 T_EOL,
622 T_STRING,
623 T_EOF,
624 T_MENU,
625 T_TITLE,
626 T_TIMEOUT,
627 T_LABEL,
628 T_KERNEL,
629 T_APPEND,
630 T_INITRD,
631 T_LOCALBOOT,
632 T_DEFAULT,
633 T_PROMPT,
634 T_INCLUDE,
635 T_INVALID
636};
637
638/*
639 * A token - given by a value and a type.
640 */
641struct token {
642 char *val;
643 enum token_type type;
644};
645
646/*
647 * Keywords recognized.
648 */
649static const struct token keywords[] = {
650 {"menu", T_MENU},
651 {"title", T_TITLE},
652 {"timeout", T_TIMEOUT},
653 {"default", T_DEFAULT},
654 {"prompt", T_PROMPT},
655 {"label", T_LABEL},
656 {"kernel", T_KERNEL},
657 {"localboot", T_LOCALBOOT},
658 {"append", T_APPEND},
659 {"initrd", T_INITRD},
660 {"include", T_INCLUDE},
661 {NULL, T_INVALID}
662};
663
664/*
665 * Since pxe(linux) files don't have a token to identify the start of a
666 * literal, we have to keep track of when we're in a state where a literal is
667 * expected vs when we're in a state a keyword is expected.
668 */
669enum lex_state {
670 L_NORMAL = 0,
671 L_KEYWORD,
672 L_SLITERAL
673};
674
675/*
676 * get_string retrieves a string from *p and stores it as a token in
677 * *t.
678 *
679 * get_string used for scanning both string literals and keywords.
680 *
681 * Characters from *p are copied into t-val until a character equal to
682 * delim is found, or a NUL byte is reached. If delim has the special value of
683 * ' ', any whitespace character will be used as a delimiter.
684 *
685 * If lower is unequal to 0, uppercase characters will be converted to
686 * lowercase in the result. This is useful to make keywords case
687 * insensitive.
688 *
689 * The location of *p is updated to point to the first character after the end
690 * of the token - the ending delimiter.
691 *
692 * On success, the new value of t->val is returned. Memory for t->val is
693 * allocated using malloc and must be free()'d to reclaim it. If insufficient
694 * memory is available, NULL is returned.
695 */
696static char *get_string(char **p, struct token *t, char delim, int lower)
697{
698 char *b, *e;
699 size_t len, i;
700
701 /*
702 * b and e both start at the beginning of the input stream.
703 *
704 * e is incremented until we find the ending delimiter, or a NUL byte
705 * is reached. Then, we take e - b to find the length of the token.
706 */
707 b = e = *p;
708
709 while (*e) {
710 if ((delim == ' ' && isspace(*e)) || delim == *e)
711 break;
712 e++;
713 }
714
715 len = e - b;
716
717 /*
718 * Allocate memory to hold the string, and copy it in, converting
719 * characters to lowercase if lower is != 0.
720 */
721 t->val = malloc(len + 1);
722 if (!t->val)
723 return NULL;
724
725 for (i = 0; i < len; i++, b++) {
726 if (lower)
727 t->val[i] = tolower(*b);
728 else
729 t->val[i] = *b;
730 }
731
732 t->val[len] = '\0';
733
734 /*
735 * Update *p so the caller knows where to continue scanning.
736 */
737 *p = e;
738
739 t->type = T_STRING;
740
741 return t->val;
742}
743
744/*
745 * Populate a keyword token with a type and value.
746 */
747static void get_keyword(struct token *t)
748{
749 int i;
750
751 for (i = 0; keywords[i].val; i++) {
752 if (!strcmp(t->val, keywords[i].val)) {
753 t->type = keywords[i].type;
754 break;
755 }
756 }
757}
758
759/*
760 * Get the next token. We have to keep track of which state we're in to know
761 * if we're looking to get a string literal or a keyword.
762 *
763 * *p is updated to point at the first character after the current token.
764 */
765static void get_token(char **p, struct token *t, enum lex_state state)
766{
767 char *c = *p;
768
769 t->type = T_INVALID;
770
771 /* eat non EOL whitespace */
772 while (isblank(*c))
773 c++;
774
775 /*
776 * eat comments. note that string literals can't begin with #, but
777 * can contain a # after their first character.
778 */
779 if (*c == '#') {
780 while (*c && *c != '\n')
781 c++;
782 }
783
784 if (*c == '\n') {
785 t->type = T_EOL;
786 c++;
787 } else if (*c == '\0') {
788 t->type = T_EOF;
789 c++;
790 } else if (state == L_SLITERAL) {
791 get_string(&c, t, '\n', 0);
792 } else if (state == L_KEYWORD) {
793 /*
794 * when we expect a keyword, we first get the next string
795 * token delimited by whitespace, and then check if it
796 * matches a keyword in our keyword list. if it does, it's
797 * converted to a keyword token of the appropriate type, and
798 * if not, it remains a string token.
799 */
800 get_string(&c, t, ' ', 1);
801 get_keyword(t);
802 }
803
804 *p = c;
805}
806
807/*
808 * Increment *c until we get to the end of the current line, or EOF.
809 */
810static void eol_or_eof(char **c)
811{
812 while (**c && **c != '\n')
813 (*c)++;
814}
815
816/*
817 * All of these parse_* functions share some common behavior.
818 *
819 * They finish with *c pointing after the token they parse, and return 1 on
820 * success, or < 0 on error.
821 */
822
823/*
824 * Parse a string literal and store a pointer it at *dst. String literals
825 * terminate at the end of the line.
826 */
827static int parse_sliteral(char **c, char **dst)
828{
829 struct token t;
830 char *s = *c;
831
832 get_token(c, &t, L_SLITERAL);
833
834 if (t.type != T_STRING) {
835 printf("Expected string literal: %.*s\n", (int)(*c - s), s);
836 return -EINVAL;
837 }
838
839 *dst = t.val;
840
841 return 1;
842}
843
844/*
845 * Parse a base 10 (unsigned) integer and store it at *dst.
846 */
847static int parse_integer(char **c, int *dst)
848{
849 struct token t;
850 char *s = *c;
851 unsigned long temp;
852
853 get_token(c, &t, L_SLITERAL);
854
855 if (t.type != T_STRING) {
856 printf("Expected string: %.*s\n", (int)(*c - s), s);
857 return -EINVAL;
858 }
859
860 if (strict_strtoul(t.val, 10, &temp) < 0) {
861 printf("Expected unsigned integer: %s\n", t.val);
862 return -EINVAL;
863 }
864
865 *dst = (int)temp;
866
867 free(t.val);
868
869 return 1;
870}
871
872static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level);
873
874/*
875 * Parse an include statement, and retrieve and parse the file it mentions.
876 *
877 * base should point to a location where it's safe to store the file, and
878 * nest_level should indicate how many nested includes have occurred. For this
879 * include, nest_level has already been incremented and doesn't need to be
880 * incremented here.
881 */
882static int handle_include(char **c, char *base,
883 struct pxe_menu *cfg, int nest_level)
884{
885 char *include_path;
886 char *s = *c;
887 int err;
888
889 err = parse_sliteral(c, &include_path);
890
891 if (err < 0) {
892 printf("Expected include path: %.*s\n",
893 (int)(*c - s), s);
894 return err;
895 }
896
897 err = get_pxe_file(include_path, base);
898
899 if (err < 0) {
900 printf("Couldn't retrieve %s\n", include_path);
901 return err;
902 }
903
904 return parse_pxefile_top(base, cfg, nest_level);
905}
906
907/*
908 * Parse lines that begin with 'menu'.
909 *
910 * b and nest are provided to handle the 'menu include' case.
911 *
912 * b should be the address where the file currently being parsed is stored.
913 *
914 * nest_level should be 1 when parsing the top level pxe file, 2 when parsing
915 * a file it includes, 3 when parsing a file included by that file, and so on.
916 */
917static int parse_menu(char **c, struct pxe_menu *cfg, char *b, int nest_level)
918{
919 struct token t;
920 char *s = *c;
921 int err;
922
923 get_token(c, &t, L_KEYWORD);
924
925 switch (t.type) {
926 case T_TITLE:
927 err = parse_sliteral(c, &cfg->title);
928
929 break;
930
931 case T_INCLUDE:
932 err = handle_include(c, b + strlen(b) + 1, cfg,
933 nest_level + 1);
934 break;
935
936 default:
937 printf("Ignoring malformed menu command: %.*s\n",
938 (int)(*c - s), s);
939 }
940
941 if (err < 0)
942 return err;
943
944 eol_or_eof(c);
945
946 return 1;
947}
948
949/*
950 * Handles parsing a 'menu line' when we're parsing a label.
951 */
952static int parse_label_menu(char **c, struct pxe_menu *cfg,
953 struct pxe_label *label)
954{
955 struct token t;
956 char *s;
957
958 s = *c;
959
960 get_token(c, &t, L_KEYWORD);
961
962 switch (t.type) {
963 case T_DEFAULT:
964 if (cfg->default_label)
965 free(cfg->default_label);
966
967 cfg->default_label = strdup(label->name);
968
969 if (!cfg->default_label)
970 return -ENOMEM;
971
972 break;
973 default:
974 printf("Ignoring malformed menu command: %.*s\n",
975 (int)(*c - s), s);
976 }
977
978 eol_or_eof(c);
979
980 return 0;
981}
982
983/*
984 * Parses a label and adds it to the list of labels for a menu.
985 *
986 * A label ends when we either get to the end of a file, or
987 * get some input we otherwise don't have a handler defined
988 * for.
989 *
990 */
991static int parse_label(char **c, struct pxe_menu *cfg)
992{
993 struct token t;
994 char *s = *c;
995 struct pxe_label *label;
996 int err;
997
998 label = label_create();
999 if (!label)
1000 return -ENOMEM;
1001
1002 err = parse_sliteral(c, &label->name);
1003 if (err < 0) {
1004 printf("Expected label name: %.*s\n", (int)(*c - s), s);
1005 label_destroy(label);
1006 return -EINVAL;
1007 }
1008
1009 list_add_tail(&label->list, &cfg->labels);
1010
1011 while (1) {
1012 s = *c;
1013 get_token(c, &t, L_KEYWORD);
1014
1015 err = 0;
1016 switch (t.type) {
1017 case T_MENU:
1018 err = parse_label_menu(c, cfg, label);
1019 break;
1020
1021 case T_KERNEL:
1022 err = parse_sliteral(c, &label->kernel);
1023 break;
1024
1025 case T_APPEND:
1026 err = parse_sliteral(c, &label->append);
1027 break;
1028
1029 case T_INITRD:
1030 err = parse_sliteral(c, &label->initrd);
1031 break;
1032
1033 case T_LOCALBOOT:
1034 err = parse_integer(c, &label->localboot);
1035 break;
1036
1037 case T_EOL:
1038 break;
1039
1040 default:
1041 /*
1042 * put the token back! we don't want it - it's the end
1043 * of a label and whatever token this is, it's
1044 * something for the menu level context to handle.
1045 */
1046 *c = s;
1047 return 1;
1048 }
1049
1050 if (err < 0)
1051 return err;
1052 }
1053}
1054
1055/*
1056 * This 16 comes from the limit pxelinux imposes on nested includes.
1057 *
1058 * There is no reason at all we couldn't do more, but some limit helps prevent
1059 * infinite (until crash occurs) recursion if a file tries to include itself.
1060 */
1061#define MAX_NEST_LEVEL 16
1062
1063/*
1064 * Entry point for parsing a menu file. nest_level indicates how many times
1065 * we've nested in includes. It will be 1 for the top level menu file.
1066 *
1067 * Returns 1 on success, < 0 on error.
1068 */
1069static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level)
1070{
1071 struct token t;
1072 char *s, *b, *label_name;
1073 int err;
1074
1075 b = p;
1076
1077 if (nest_level > MAX_NEST_LEVEL) {
1078 printf("Maximum nesting (%d) exceeded\n", MAX_NEST_LEVEL);
1079 return -EMLINK;
1080 }
1081
1082 while (1) {
1083 s = p;
1084
1085 get_token(&p, &t, L_KEYWORD);
1086
1087 err = 0;
1088 switch (t.type) {
1089 case T_MENU:
1090 err = parse_menu(&p, cfg, b, nest_level);
1091 break;
1092
1093 case T_TIMEOUT:
1094 err = parse_integer(&p, &cfg->timeout);
1095 break;
1096
1097 case T_LABEL:
1098 err = parse_label(&p, cfg);
1099 break;
1100
1101 case T_DEFAULT:
1102 err = parse_sliteral(&p, &label_name);
1103
1104 if (label_name) {
1105 if (cfg->default_label)
1106 free(cfg->default_label);
1107
1108 cfg->default_label = label_name;
1109 }
1110
1111 break;
1112
1113 case T_PROMPT:
1114 err = parse_integer(&p, &cfg->prompt);
1115 break;
1116
1117 case T_EOL:
1118 break;
1119
1120 case T_EOF:
1121 return 1;
1122
1123 default:
1124 printf("Ignoring unknown command: %.*s\n",
1125 (int)(p - s), s);
1126 eol_or_eof(&p);
1127 }
1128
1129 if (err < 0)
1130 return err;
1131 }
1132}
1133
1134/*
1135 * Free the memory used by a pxe_menu and its labels.
1136 */
1137static void destroy_pxe_menu(struct pxe_menu *cfg)
1138{
1139 struct list_head *pos, *n;
1140 struct pxe_label *label;
1141
1142 if (cfg->title)
1143 free(cfg->title);
1144
1145 if (cfg->default_label)
1146 free(cfg->default_label);
1147
1148 list_for_each_safe(pos, n, &cfg->labels) {
1149 label = list_entry(pos, struct pxe_label, list);
1150
1151 label_destroy(label);
1152 }
1153
1154 free(cfg);
1155}
1156
1157/*
1158 * Entry point for parsing a pxe file. This is only used for the top level
1159 * file.
1160 *
1161 * Returns NULL if there is an error, otherwise, returns a pointer to a
1162 * pxe_menu struct populated with the results of parsing the pxe file (and any
1163 * files it includes). The resulting pxe_menu struct can be free()'d by using
1164 * the destroy_pxe_menu() function.
1165 */
1166static struct pxe_menu *parse_pxefile(char *menucfg)
1167{
1168 struct pxe_menu *cfg;
1169
1170 cfg = malloc(sizeof(struct pxe_menu));
1171
1172 if (!cfg)
1173 return NULL;
1174
1175 memset(cfg, 0, sizeof(struct pxe_menu));
1176
1177 INIT_LIST_HEAD(&cfg->labels);
1178
1179 if (parse_pxefile_top(menucfg, cfg, 1) < 0) {
1180 destroy_pxe_menu(cfg);
1181 return NULL;
1182 }
1183
1184 return cfg;
1185}
1186
1187/*
1188 * Converts a pxe_menu struct into a menu struct for use with U-boot's generic
1189 * menu code.
1190 */
1191static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg)
1192{
1193 struct pxe_label *label;
1194 struct list_head *pos;
1195 struct menu *m;
1196 int err;
1197
1198 /*
1199 * Create a menu and add items for all the labels.
1200 */
1201 m = menu_create(cfg->title, cfg->timeout, cfg->prompt, label_print);
1202
1203 if (!m)
1204 return NULL;
1205
1206 list_for_each(pos, &cfg->labels) {
1207 label = list_entry(pos, struct pxe_label, list);
1208
1209 if (menu_item_add(m, label->name, label) != 1) {
1210 menu_destroy(m);
1211 return NULL;
1212 }
1213 }
1214
1215 /*
1216 * After we've created items for each label in the menu, set the
1217 * menu's default label if one was specified.
1218 */
1219 if (cfg->default_label) {
1220 err = menu_default_set(m, cfg->default_label);
1221 if (err != 1) {
1222 if (err != -ENOENT) {
1223 menu_destroy(m);
1224 return NULL;
1225 }
1226
1227 printf("Missing default: %s\n", cfg->default_label);
1228 }
1229 }
1230
1231 return m;
1232}
1233
1234/*
1235 * Try to boot any labels we have yet to attempt to boot.
1236 */
1237static void boot_unattempted_labels(struct pxe_menu *cfg)
1238{
1239 struct list_head *pos;
1240 struct pxe_label *label;
1241
1242 list_for_each(pos, &cfg->labels) {
1243 label = list_entry(pos, struct pxe_label, list);
1244
1245 if (!label->attempted)
1246 label_boot(label);
1247 }
1248}
1249
1250/*
1251 * Boot the system as prescribed by a pxe_menu.
1252 *
1253 * Use the menu system to either get the user's choice or the default, based
1254 * on config or user input. If there is no default or user's choice,
1255 * attempted to boot labels in the order they were given in pxe files.
1256 * If the default or user's choice fails to boot, attempt to boot other
1257 * labels in the order they were given in pxe files.
1258 *
1259 * If this function returns, there weren't any labels that successfully
1260 * booted, or the user interrupted the menu selection via ctrl+c.
1261 */
1262static void handle_pxe_menu(struct pxe_menu *cfg)
1263{
1264 void *choice;
1265 struct menu *m;
1266 int err;
1267
1268 m = pxe_menu_to_menu(cfg);
1269 if (!m)
1270 return;
1271
1272 err = menu_get_choice(m, &choice);
1273
1274 menu_destroy(m);
1275
1276 if (err < 1)
1277 return;
1278
1279 label_boot(choice);
1280
1281 boot_unattempted_labels(cfg);
1282}
1283
1284/*
1285 * Boots a system using a pxe file
1286 *
1287 * Returns 0 on success, 1 on error.
1288 */
1289static int
1290do_pxe_boot(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
1291{
1292 unsigned long pxefile_addr_r;
1293 struct pxe_menu *cfg;
1294 char *pxefile_addr_str;
1295
1296 if (argc == 1) {
1297 pxefile_addr_str = from_env("pxefile_addr_r");
1298 if (!pxefile_addr_str)
1299 return 1;
1300
1301 } else if (argc == 2) {
1302 pxefile_addr_str = argv[1];
1303 } else {
1304 return cmd_usage(cmdtp);
1305 }
1306
1307 if (strict_strtoul(pxefile_addr_str, 16, &pxefile_addr_r) < 0) {
1308 printf("Invalid pxefile address: %s\n", pxefile_addr_str);
1309 return 1;
1310 }
1311
1312 cfg = parse_pxefile((char *)(pxefile_addr_r));
1313
1314 if (cfg == NULL) {
1315 printf("Error parsing config file\n");
1316 return 1;
1317 }
1318
1319 handle_pxe_menu(cfg);
1320
1321 destroy_pxe_menu(cfg);
1322
1323 return 0;
1324}
1325
1326static cmd_tbl_t cmd_pxe_sub[] = {
1327 U_BOOT_CMD_MKENT(get, 1, 1, do_pxe_get, "", ""),
1328 U_BOOT_CMD_MKENT(boot, 2, 1, do_pxe_boot, "", "")
1329};
1330
1331int do_pxe(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
1332{
1333 cmd_tbl_t *cp;
1334
1335 if (argc < 2)
1336 return cmd_usage(cmdtp);
1337
1338 /* drop initial "pxe" arg */
1339 argc--;
1340 argv++;
1341
1342 cp = find_cmd_tbl(argv[0], cmd_pxe_sub, ARRAY_SIZE(cmd_pxe_sub));
1343
1344 if (cp)
1345 return cp->cmd(cmdtp, flag, argc, argv);
1346
1347 return cmd_usage(cmdtp);
1348}
1349
1350U_BOOT_CMD(
1351 pxe, 3, 1, do_pxe,
1352 "commands to get and boot from pxe files",
1353 "get - try to retrieve a pxe file using tftp\npxe "
1354 "boot [pxefile_addr_r] - boot from the pxe file at pxefile_addr_r\n"
1355);