xref: /xnu-10002.61.3/libkern/kxld/kxld_sect.h (revision 0f4c859e951fba394238ab619495c4e1d54d0f34)
1 /*
2  * Copyright (c) 2008 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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23  * Please see the License for the specific language governing rights and
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27  */
28 #ifndef _KXLD_SECT_H_
29 #define _KXLD_SECT_H_
30 
31 #include <sys/types.h>
32 #if KERNEL
33     #include <libkern/kxld_types.h>
34 #else
35     #include "kxld_types.h"
36 #endif
37 
38 #include "kxld_array.h"
39 
40 struct kxld_array;
41 struct kxld_relocator;
42 struct kxld_reloc;
43 struct kxld_seg;
44 struct kxld_symtab;
45 struct relocation_info;
46 struct section;
47 struct section_64;
48 typedef struct kxld_sect KXLDSect;
49 
50 struct kxld_sect {
51 	char sectname[16];          // The name of the section
52 	char segname[16];           // The segment to which the section belongs
53 	u_char *data;               // The start of the section in memory
54 	KXLDArray relocs;           // The section's relocation entries
55 	kxld_addr_t base_addr;      // The base address of the section
56 	kxld_addr_t link_addr;      // The relocated address of the section
57 	kxld_size_t size;           // The size of the section
58 	u_int sectnum;              // The number of the section (for relocation)
59 	u_int flags;                // Flags describing the section
60 	u_int align;                // The section's alignment as a power of 2
61 	u_int reserved1;            // Dependent on the section type
62 	u_int reserved2;            // Dependent on the section type
63 	boolean_t allocated;        // This section's data is allocated internally
64 };
65 
66 /*******************************************************************************
67 * Constructors and destructors
68 *******************************************************************************/
69 
70 #if KXLD_USER_OR_ILP32
71 /* Initializes a section object from a Mach-O section header and modifies the
72  * section offset to point to the next section header.
73  */
74 kern_return_t kxld_sect_init_from_macho_32(KXLDSect *sect, u_char *macho,
75     u_long *sect_offset, u_int sectnum, const struct kxld_relocator *relocator)
76 __attribute__((nonnull, visibility("hidden")));
77 #endif /* KXLD_USER_OR_ILP32 */
78 
79 #if KXLD_USER_OR_LP64
80 /* Initializes a section object from a Mach-O64 section header and modifies the
81  * section offset to point to the next section header.
82  */
83 kern_return_t kxld_sect_init_from_macho_64(KXLDSect *sect, u_char *macho,
84     u_long *sect_offset, u_int sectnum, const struct kxld_relocator *relocator)
85 __attribute__((nonnull, visibility("hidden")));
86 #endif /* KXLD_USER_OR_LP64 */
87 
88 #if KXLD_USER_OR_GOT
89 /* Initializes a GOT section from the number of entries that the section should
90  * have.
91  */
92 kern_return_t kxld_sect_init_got(KXLDSect *sect, u_int ngots)
93 __attribute__((nonnull, visibility("hidden")));
94 #endif /* KXLD_USER_OR_GOT */
95 
96 #if KXLD_USER_OR_COMMON
97 /* Initializes a zerofill section of the specified size and alignment */
98 void kxld_sect_init_zerofill(KXLDSect *sect, const char *segname,
99     const char *sectname, kxld_size_t size, u_int align)
100 __attribute__((nonnull, visibility("hidden")));
101 #endif /* KXLD_USER_OR_COMMON */
102 
103 /* Clears the section object */
104 void kxld_sect_clear(KXLDSect *sect)
105 __attribute__((nonnull, visibility("hidden")));
106 
107 /* Denitializes the section object and frees its array of relocs */
108 void kxld_sect_deinit(KXLDSect *sect)
109 __attribute__((nonnull, visibility("hidden")));
110 
111 /*******************************************************************************
112 * Accessors
113 *******************************************************************************/
114 
115 /* Gets the number of relocation entries in the section */
116 u_int kxld_sect_get_num_relocs(const KXLDSect *sect)
117 __attribute__((pure, nonnull, visibility("hidden")));
118 
119 /* Returns the address parameter adjusted to the minimum alignment required by
120  * the section.
121  */
122 kxld_addr_t kxld_sect_align_address(const KXLDSect *sect, kxld_addr_t address)
123 __attribute__((pure, nonnull, visibility("hidden")));
124 
125 /* Returns the space required by the exported Mach-O header */
126 u_long kxld_sect_get_macho_header_size(boolean_t is_32_bit)
127 __attribute__((const, visibility("hidden")));
128 
129 /* Returns the space required by the exported Mach-O data */
130 u_long kxld_sect_get_macho_data_size(const KXLDSect *sect)
131 __attribute__((pure, nonnull, visibility("hidden")));
132 
133 #if KXLD_USER_OR_LP64
134 /* Returns the number of GOT entries required by relocation entries in the
135  * given section.
136  */
137 u_int kxld_sect_get_ngots(const KXLDSect *sect,
138     const struct kxld_relocator *relocator, const struct kxld_symtab *symtab)
139 __attribute__((pure, nonnull, visibility("hidden")));
140 #endif /* KXLD_USER_OR_LP64 */
141 
142 kern_return_t kxld_sect_export_macho_to_file_buffer(const KXLDSect *sect, u_char *buf,
143     u_long *header_offset, u_long header_size, u_long *data_offset,
144     u_long data_size, boolean_t is_32_bit)
145 __attribute__((nonnull, visibility("hidden")));
146 
147 kern_return_t kxld_sect_export_macho_to_vm(const KXLDSect *sect, u_char *buf,
148     u_long *header_offset,
149     u_long header_size,
150     kxld_addr_t link_addr,
151     u_long data_size,
152     boolean_t is_32_bit)
153 __attribute__((nonnull, visibility("hidden")));
154 
155 /*******************************************************************************
156 * Mutators
157 *******************************************************************************/
158 
159 /* Relocates the section to the given link address */
160 void kxld_sect_relocate(KXLDSect *sect, kxld_addr_t link_addr)
161 __attribute__((nonnull, visibility("hidden")));
162 
163 #if KXLD_USER_OR_COMMON
164 /* Adds a number of bytes to the section's size.  Returns the size of the
165  * section before it was grown.
166  */
167 kxld_size_t kxld_sect_grow(KXLDSect *sect, kxld_size_t nbytes, u_int align)
168 __attribute__((nonnull, visibility("hidden")));
169 #endif /* KXLD_USER_OR_COMMON */
170 
171 #if KXLD_USER_OR_GOT
172 /* Popluates the entries of a GOT section */
173 kern_return_t kxld_sect_populate_got(KXLDSect *sect, struct kxld_symtab *symtab,
174     boolean_t swap)
175 __attribute__((nonnull, visibility("hidden")));
176 #endif /* KXLD_USER_OR_GOT */
177 
178 /* Processes all of a section's relocation entries */
179 kern_return_t kxld_sect_process_relocs(KXLDSect *sect,
180     struct kxld_relocator *relocator)
181 __attribute__((nonnull, visibility("hidden")));
182 
183 #endif /* _KXLD_SECT_H_ */
184