xref: /illumos-gate/usr/src/lib/libgrubmgmt/common/libgrub_impl.h (revision 2983dda76a6d296fdb560c88114fe41caad1b84f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_GRBMIMPL_H
27 #define	_GRBMIMPL_H
28 
29 #ifdef	__cplusplus
30 extern "C" {
31 #endif
32 
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/mntent.h>
36 #include <sys/uadmin.h>
37 #include <libzfs.h>
38 #include <libdevinfo.h>
39 #include "libgrubmgmt.h"
40 #include "libgrub_errno.h"
41 
42 /*
43  * Macros for processing the GRUB menu.
44  */
45 #define	GRUB_MENU	"/boot/grub/menu.lst"
46 #define	BOOTSIGN_DIR	"/boot/grub/bootsign"
47 #define	BOOTSIGN_LEN	(2 * MAXNAMELEN)
48 #define	ZFS_BOOT_VAR	"$ZFS-BOOTFS"	/* ZFS boot option */
49 #define	ISADIR_VAR	"$ISADIR"	/* ISADIR option */
50 
51 #define	PRTNUM_INVALID	-1	/* Partition number invlaid */
52 #define	SLCNUM_INVALID	-1	/* Slice number invalid */
53 
54 #define	SLCNUM_FIRST		'a'
55 #define	SLCNUM_WHOLE_DISK	'q'
56 
57 #define	IS_SLCNUM_VALID(x)	((x) >= SLCNUM_FIRST && (x) < SLCNUM_WHOLE_DISK)
58 #define	IS_PRTNUM_VALID(x)	((uint_t)(x) < FD_NUMPART)
59 
60 #define	GRBM_VALID_FLAG		((uint_t)1 << 31)
61 #define	GRBM_MAXLINE		8192
62 #define	IS_ENTRY_VALID(ent)	((ent) && ((ent)->ge_flags & GRBM_VALID_FLAG))
63 #define	IS_BARG_VALID(barg)	((barg)->gb_flags & GRBM_VALID_FLAG)
64 #define	IS_ENTRY_BARG_VALID(ent) \
65 	(IS_ENTRY_VALID(ent) && IS_BARG_VALID(&(ent)->ge_barg))
66 #define	IS_LINE2BIG(buf, bfsz, len) \
67 	((len = strlen(buf)) == (bfsz) - 1 && (buf)[len - 1] != '\n')
68 #define	IS_STR_NULL(x)	((x) == NULL ? "NULL" : (x))
69 #define	GRUB_ENTRY_IS_XVM(fbarg) \
70 	(strstr(fbarg.gba_kernel, "xen.gz") != NULL)
71 
72 enum {
73 #define	menu_cmd(cmd, num, flags, parsef)	num,
74 #define	menu_cmd_end(num)			num
75 #include "libgrub_cmd.def"
76 };
77 
78 typedef struct _grub_fs {
79 	di_node_t		gf_diroot;
80 	di_devlink_handle_t	gf_dvlh;
81 	libzfs_handle_t		*gf_lzfh;
82 } grub_fs_t;
83 
84 
85 typedef struct _grub_cmd_desc {
86 	const char	*gcd_cmd;
87 	uint_t		gcd_num;
88 	int		gcd_flags;
89 } grub_cmd_desc_t;
90 
91 
92 enum {
93 	GRBM_UFS = 0,
94 	GRBM_ZFS_TOPFS = 0,
95 	GRBM_FS_TOP = 0,
96 	GRBM_ZFS_BOOTFS,
97 	GRBM_FS_MAX
98 };
99 
100 typedef struct _grub_root {
101 	char		gr_fstyp[MNTMAXSTR];
102 	char		gr_physpath[MAXPATHLEN];
103 	grub_fsdesc_t	gr_fs[GRBM_FS_MAX];
104 } grub_root_t;
105 
106 /*
107  * Data struct for the boot argument constructed from a GRUB menu entry
108  */
109 typedef struct _grub_barg {
110 	grub_entry_t	*gb_entry;
111 	grub_line_t	*gb_errline;
112 	int		gb_walkret;	/* set to 0 when match found */
113 	uint_t		gb_flags;
114 	uint_t		gb_prtnum;
115 	uint_t		gb_slcnum;
116 	grub_root_t	gb_root;
117 	char		gb_bootsign[BOOTSIGN_LEN];
118 	char		gb_kernel[BOOTARGS_MAX];
119 	char		gb_module[BOOTARGS_MAX];
120 } grub_barg_t;
121 
122 
123 /* GRUB menu per-line classification */
124 enum {
125 	GRUB_LINE_INVALID = 0,
126 	GRUB_LINE_EMPTY,
127 	GRUB_LINE_COMMENT,
128 	GRUB_LINE_GLOBAL,
129 	GRUB_LINE_ENTRY,
130 	GRUB_LINE_TITLE
131 };
132 
133 /*
134  * Data structures for menu.lst contents
135  */
136 struct grub_line {
137 	grub_line_t	*gl_next;
138 	grub_line_t	*gl_prev;
139 	int		gl_line_num;	/* Line number in menu.lst */
140 	int		gl_entry_num;	/* menu boot entry #. */
141 					/* GRUB_ENTRY_DEFAULT if none */
142 	int		gl_flags;
143 	uint_t		gl_cmdtp;	/* recognized command type */
144 	char		*gl_cmd;
145 	char		*gl_sep;
146 	char		*gl_arg;
147 	char		*gl_line;
148 };
149 
150 struct grub_entry {
151 	grub_menu_t	*ge_menu;	/* grub_menu_t it belongs to */
152 	grub_entry_t	*ge_next;
153 	grub_entry_t	*ge_prev;
154 	grub_line_t	*ge_start;
155 	grub_line_t	*ge_end;
156 	int		ge_entry_num;
157 	uint_t		ge_flags;
158 	uint_t		ge_emask;	/* invalid lines mask */
159 	grub_barg_t	ge_barg;
160 };
161 
162 struct grub_menu {
163 	grub_line_t	*gm_start;
164 	grub_line_t	*gm_end;
165 	grub_line_t	*gm_curdefault;	/* line containing default */
166 	grub_entry_t	*gm_ent_start;	/* os entries */
167 	grub_entry_t	*gm_ent_end;
168 	grub_entry_t	*gm_ent_default;	/* default entry */
169 	uint_t		gm_line_num;	/* number of lines processed */
170 	uint_t		gm_entry_num;	/* number of entries processed */
171 	char		gm_path[MAXPATHLEN];
172 	grub_fs_t	gm_fs;
173 	grub_root_t	gm_root;
174 };
175 
176 /* File system helper functions */
177 int grub_current_root(grub_fs_t *, grub_root_t *);
178 grub_fsdesc_t *grub_get_rootfsd(const grub_root_t *);
179 int grub_fsd_mount_tmp(grub_fsdesc_t *, const char *);
180 void grub_fsd_umount_tmp(grub_fsdesc_t *);
181 int grub_fsd_get_mountp(grub_fsdesc_t *fsd, char *fstyp);
182 int grub_find_bootsign(grub_barg_t *barg);
183 
184 
185 /* GRUB menu parse functions */
186 int skip_line(const grub_line_t *lp, grub_barg_t *barg);
187 int error_line(const grub_line_t *lp, grub_barg_t *barg);
188 int kernel(const grub_line_t *lp, grub_barg_t *barg);
189 int module(const grub_line_t *lp, grub_barg_t *barg);
190 int dollar_kernel(const grub_line_t *lp, grub_barg_t *barg);
191 int dollar_module(const grub_line_t *lp, grub_barg_t *barg);
192 int findroot(const grub_line_t *lp, grub_barg_t *barg);
193 int bootfs(const grub_line_t *lp, grub_barg_t *barg);
194 size_t clean_path(char *path);
195 
196 
197 /* GRUB entry functions */
198 int grub_entry_construct_barg(grub_entry_t *ent);
199 const char *grub_entry_get_fstyp(const grub_entry_t *ent);
200 const char *grub_entry_get_kernel(const grub_entry_t *ent);
201 const char *grub_entry_get_module(const grub_entry_t *ent);
202 const grub_fsdesc_t *grub_entry_get_rootfs(const grub_entry_t *ent);
203 size_t grub_entry_get_cmdline(grub_entry_t *ent, char *cmdline, size_t size);
204 
205 /*
206  * GRUB menu parse/access funcions.
207  *
208  * Callers must call grub_menu_init() to to obtain a handle to the menu before
209  * calling any of the other functions, and call grub_menu_fini() to close.
210  *
211  * grub_menu_init:
212  *	Reads and parses GRUB menu file into a grub_menu_t data structure.
213  *	If grub_menu_path file path is NULL, will use 'currently active'
214  *	GRUB menu file.
215  * grub_menu_fini:
216  *	Frees all resources allocated by grub_menu_init().
217  *
218  * grub_menu_get_entry:
219  *	Returns a particular entry from the menu.
220  * grub_menu_next_entry:
221  * grub_menu_prev_entry:
222  *      Returns next or previous entry in the menu.
223  *      If current entry is NULL, return first or last entry.
224  *
225  * grub_menu_next_line:
226  * grub_menu_prev_line:
227  *      Returns next/prev (to the current) line in the menu.
228  *      If current line is NULL, returns first or last line.
229  * grub_menu_get_line:
230  *      Returns the specified line in the menu (line counter starts from one).
231  */
232 int grub_menu_init(const char *grub_menu_path, grub_menu_t **menup);
233 void grub_menu_fini(grub_menu_t *);
234 grub_entry_t *grub_menu_get_entry(const grub_menu_t *menu, int num);
235 grub_entry_t *grub_menu_next_entry(const grub_menu_t *menu,
236     const grub_entry_t *current);
237 grub_entry_t *grub_menu_prev_entry(const grub_menu_t *menu,
238     const grub_entry_t *current);
239 grub_line_t *grub_menu_next_line(const grub_menu_t *menu,
240     const grub_line_t *current);
241 grub_line_t *grub_menu_prev_line(const grub_menu_t *menu,
242     const grub_line_t *current);
243 
244 #ifdef __cplusplus
245 }
246 #endif
247 
248 #endif	/* _GRBMIMPL_H */
249