xref: /titanic_41/usr/src/uts/intel/amd64/krtld/doreloc.c (revision fa9e4066f08beec538e775443c5be79dd423fcab)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #if	defined(_KERNEL)
30 #include	<sys/types.h>
31 #include	"reloc.h"
32 #else
33 #include	<stdio.h>
34 #include	"sgs.h"
35 #include	"machdep.h"
36 #include	"libld.h"
37 #include	"reloc.h"
38 #include	"conv.h"
39 #include	"msg.h"
40 #endif
41 
42 /*
43  * This table represents the current relocations that do_reloc()
44  * is able to process.  The relocations below that are marked
45  * 'SPECIAL' in the comments are relocations that take special
46  * processing and shouldn't actually ever be passed to do_reloc().
47  */
48 const Rel_entry	reloc_table[R_AMD64_NUM] = {
49 /* R_AMD64_NONE */	{0, 0},
50 /* R_AMD64_64 */	{FLG_RE_NOTREL, 8},
51 /* R_AMD64_PC32 */	{FLG_RE_PCREL, 4},
52 /* R_AMD64_GOT32 */	{FLG_RE_NOTSUP, 0},
53 /* R_AMD64_PLT32 */	{FLG_RE_PCREL | FLG_RE_PLTREL |
54 				FLG_RE_VERIFY | FLG_RE_SIGN, 4},
55 /* R_AMD64_COPY */	{FLG_RE_NOTSUP, 0},
56 /* R_AMD64_GLOB_DAT */	{FLG_RE_NOTREL, 8},
57 /* R_AMD64_JUMP_SLOT */	{FLG_RE_NOTSUP, 0},
58 /* R_AMD64_RELATIVE */	{FLG_RE_NOTREL, 8},
59 /* R_AMD64_GOTPCREL */	{FLG_RE_GOTPC | FLG_RE_GOTADD, 4},
60 /* R_AMD64_32 */	{FLG_RE_NOTREL, 4},
61 /* R_AMD64_32S */	{FLG_RE_NOTREL, 4},
62 /* R_AMD64_16 */	{FLG_RE_NOTSUP, 0},
63 /* R_AMD64_PC16 */	{FLG_RE_NOTSUP, 0},
64 /* R_AMD64_8 */		{FLG_RE_NOTSUP, 0},
65 /* R_AMD64_PC8 */	{FLG_RE_NOTSUP, 0},
66 /* R_AMD64_DTPMOD64 */	{FLG_RE_NOTREL, 8},
67 /* R_AMD64_DTPOFF64 */	{FLG_RE_NOTREL, 8},
68 /* R_AMD64_TPOFF64 */	{FLG_RE_NOTREL, 8},
69 /* R_AMD64_TLSGD */	{FLG_RE_GOTPC | FLG_RE_GOTADD |
70 			    FLG_RE_TLSINS | FLG_RE_TLSGD, 4},
71 /* R_AMD64_TLSLD */	{FLG_RE_GOTPC | FLG_RE_GOTADD |
72 			    FLG_RE_TLSINS | FLG_RE_TLSLD, 4},
73 /* R_AMD64_DTPOFF32 */	{FLG_RE_TLSINS | FLG_RE_NOTREL | FLG_RE_TLSLD, 4},
74 /* R_AMD64_GOTTPOFF */	{FLG_RE_GOTPC | FLG_RE_GOTADD |
75 			    FLG_RE_TLSINS | FLG_RE_TLSIE, 4},
76 /* R_AMD64_TPOFF32 */	{FLG_RE_TLSINS | FLG_RE_NOTREL | FLG_RE_TLSLE, 4},
77 /* R_AMD64_PC64 */	{FLG_RE_PCREL, 8},
78 /* R_AMD64_GOTOFF64 */	{FLG_RE_GOTREL, 8},
79 /* R_AMD64_GOTPC32 */	{FLG_RE_PCREL | FLG_RE_GOTPC | FLG_RE_LOCLBND, 4}
80 };
81 #if	(R_AMD64_NUM != (R_AMD64_GOTPC32 + 1))
82 #error	"R_AMD64_NUM has grown"
83 #endif
84 
85 /*
86  * Write a single relocated value to its reference location.
87  * We assume we wish to add the relocatoin amount, value, to the
88  * value of the address already present at the offset.
89  *
90  * NAME			VALUE	FIELD		CALCULATION
91  *
92  * R_AMD64_NONE		 0	none		none
93  * R_AMD64_64		 1	word64		S + A
94  * R_AMD64_PC32		 2	word64		S + A
95  * R_AMD64_GOT32	 3	word32		G + A
96  * R_AMD64_PLT32	 4	word32		L + A - P
97  * R_AMD64_COPY		 5	none		none
98  * R_AMD64_GLOB_DAT	 6	word64		S
99  * R_AMD64_JUMP_SLOT	 7	word64		S
100  * R_AMD64_RELATIVE	 8	word64		B + A
101  * R_AMD64_GOTPCREL	 9	word32		G + GOT + A - P
102  * R_AMD64_32		10	word32		S + A
103  * R_AMD64_32S		11	word32		S + A
104  * R_AMD64_16		12	word16		S + A
105  * R_AMD64_PC16		13	word16		S + A - P
106  * R_AMD64_8		14	word8		S + A
107  * R_AMD64_PC8		15	word8		S + A - P
108  * R_AMD64_DTPMOD64	16	word64
109  * R_AMD64_DTPOFF64	17	word64
110  * R_AMD64_TPOFF64	18	word64
111  * R_AMD64_TLSGD	19	word32
112  * R_AMD64_TLSLD	20	word32
113  * R_AMD64_DTPOFF32	21	word32
114  * R_AMD64_GOTTPOFF	22	word32
115  * R_AMD64_TPOFF32	23	word32
116  * R_AMD64_PC64		24	word32		S + A - P
117  * R_AMD64_GOTOFF64	25	word32		S + A - GOT
118  * R_AMD64_GOTPC32	26	word32		GOT + A - P
119  *
120  * Relocation calculations:
121  *	A	Represents the addend used to compute the value of the
122  *		relocatable field.
123  *
124  *	B	Represents the base address at which a shared objects has
125  *		been loaded into memory during executaion.  Generally, a
126  *		shared objects is built with a 0 base virtual address,
127  *		but the execution address will be different.
128  *
129  *	G	Represents the offset into the global offset table
130  *		at which the relocation entry's symbol will reside
131  *		during execution.
132  *
133  *	GOT	Rrepresents the address of the global offset table.
134  *
135  *	L	Represents the place (section offset or address) of
136  *		the Procedure Linkage Table entry for a symbol.
137  *
138  *	P	Represents the place (section offset or address) of the
139  *		storage unit being relocated (computed using r_offset).
140  *
141  *	S	Represents the value of the symbol whose index resides
142  *		in the relocation entry.
143  *
144  */
145 
146 #define	HIBITS	0xffffffff80000000ULL
147 
148 int
149 do_reloc(unsigned char rtype, unsigned char *off, Xword *value,
150 	const char *sym, const char *file)
151 {
152 	const Rel_entry	*rep;
153 
154 	rep = &reloc_table[rtype];
155 
156 	if (rep->re_fsize == 4) {
157 		/*
158 		 * The amd64 psABI requires that we perform
159 		 * the following verifications:
160 		 *
161 		 *    The R_AMD64_32 and R_AMD64_32S relocations
162 		 *    truncate the computed value to 32bits.  The linker
163 		 *    must verify that the generated value for the
164 		 *    R_AMD64_32(R_AMD64_32S) relocation zero-extends
165 		 *    (sign extends) to the original 64-bit value.
166 		 *
167 		 * Also - the following relocations are all 32 bit PC relative
168 		 * references, so we must validate that the value being
169 		 * written will fit in the field provided.
170 		 *
171 		 *  R_AMD64_PC32, R_AMD64_GOTPC32, R_AMD64_GOTPCREL
172 		 */
173 		if (rtype == R_AMD64_32) {
174 			/*
175 			 * We must verify that this value will 'zero-extend',
176 			 * this requires that the upper 33bits all be
177 			 * 'zero'.
178 			 */
179 			if ((*value & HIBITS) != 0) {
180 				/*
181 				 * to keep chkmsg() happy:
182 				 *  MSG_INTL(MSG_REL_NOFIT)
183 				 */
184 				REL_ERR_NOFIT(file, sym, rtype, *value);
185 				return (0);
186 			}
187 		} else if ((rtype == R_AMD64_32S) ||
188 			(rtype == R_AMD64_PC32) ||
189 			(rtype == R_AMD64_GOTPCREL) ||
190 			(rtype == R_AMD64_GOTPC32)) {
191 			/*
192 			 * We must verify that this value will properly
193 			 * sign extend.  This is true of the upper
194 			 * 33bits are all either 'zero' or
195 			 * all 'one'.
196 			 */
197 			if (((*value & HIBITS) != HIBITS) &&
198 			    ((*value & HIBITS) != 0)) {
199 				/*
200 				 * to keep chkmsg() happy:
201 				 *  MSG_INTL(MSG_REL_NOFIT)
202 				 */
203 				REL_ERR_NOFIT(file, sym, rtype, *value);
204 				return (0);
205 			}
206 		}
207 		/* LINTED */
208 		*((Word *)off) += *value;
209 	} else if (rep->re_fsize == 8) {
210 		*((Xword *)off) += *value;
211 	} else {
212 		eprintf(ERR_FATAL, MSG_INTL(MSG_REL_UNSUPSZ),
213 		    conv_reloc_amd64_type_str(rtype), file,
214 		    (sym ? sym : MSG_INTL(MSG_STR_UNKNOWN)),
215 		    EC_WORD(rep->re_fsize));
216 		return (0);
217 	}
218 	return (1);
219 }
220