xref: /illumos-gate/usr/src/cmd/sgs/librtld_db/sparcv9/plt64_resolution.c (revision 012e6ce759c490003aed29439cc47d3d73a99ad3)
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 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include	<proc_service.h>
28 #include	<link.h>
29 #include	<rtld_db.h>
30 #include	<_rtld_db.h>
31 #include	<msg.h>
32 
33 /*
34  * A un-initialized SPARCV9 PLT look like so:
35  *
36  * .PLT
37  *	sethi	(. - .PLT0), %g1
38  *	ba,a	%xcc, .PLT1
39  *	nop
40  *	nop
41  *	nop
42  *	nop
43  *	nop
44  *	nop
45  *
46  * To test to see if this is an uninitialized PLT we check
47  * the second instruction and confirm that it's a branch.
48  */
49 /* ARGSUSED 2 */
50 rd_err_e
51 plt64_resolution(rd_agent_t *rap, psaddr_t pc, lwpid_t lwpid,
52 	psaddr_t pltbase, rd_plt_info_t *rpi)
53 {
54 	instr_t		instr[8];
55 	rd_err_e	rerr;
56 	psaddr_t	destaddr = 0;
57 	psaddr_t	pltoff;
58 	int		pltbound = 0;
59 
60 	if (rtld_db_version >= RD_VERSION3) {
61 		rpi->pi_flags = 0;
62 		rpi->pi_baddr = 0;
63 	}
64 
65 	pltoff = pc - pltbase;
66 
67 	if (pltoff >= (M64_PLT_NEARPLTS * M64_PLT_ENTSIZE)) {
68 		psaddr_t	pltptr, pltptrval;
69 		psaddr_t	pltaddr;
70 		psaddr_t	pltblockoff;
71 
72 		/*
73 		 * Handle far PLT's
74 		 *
75 		 * .PLT#
76 		 * 0	mov	%o7, %g5
77 		 * 1	call	. + 8
78 		 * 2	nop
79 		 * 3	ldx	[%o7 + (.PLTP# - .PLT#+4)], %g1
80 		 * 4	jmpl	%o7 + %g1, %g1
81 		 * 5	mov	%g5, %o7
82 		 */
83 
84 		pltblockoff = pltoff - (M64_PLT_NEARPLTS * M64_PLT_ENTSIZE);
85 		pltblockoff =
86 			((pltblockoff / M64_PLT_FBLOCKSZ) * M64_PLT_FBLOCKSZ) +
87 			(((pltblockoff % M64_PLT_FBLOCKSZ) / M64_PLT_FENTSIZE) *
88 			M64_PLT_FENTSIZE);
89 
90 
91 		pltaddr = pltbase + (M64_PLT_NEARPLTS * M64_PLT_ENTSIZE) +
92 			pltblockoff;
93 
94 		if (ps_pread(rap->rd_psp, pltaddr, (char *)instr,
95 		    M64_PLT_FENTSIZE) != PS_OK) {
96 			LOG(ps_plog(MSG_ORIG(MSG_DB_READFAIL_2),
97 				EC_ADDR(pltaddr)));
98 			return (RD_ERR);
99 
100 		}
101 
102 		if (instr[0] != M_MOVO7TOG5) {
103 			LOG(ps_plog(MSG_ORIG(MSG_DB_BADFPLT),
104 				EC_ADDR(pltaddr), EC_ADDR(instr[0])));
105 			return (RD_ERR);
106 		}
107 
108 		/*
109 		 * the offset is a positive displacement from the
110 		 * ldx [%o7 + #], %g1 instruction.  So - we don't
111 		 * need to worry about the sign bit :)
112 		 */
113 		pltptr = instr[3] & S_MASK(12);
114 		pltptr += pltaddr + 4;
115 		/*
116 		 * Load the pltptr to determine whether it is
117 		 * pointing to .PLT0 or to the final
118 		 * destination.
119 		 */
120 		if (ps_pread(rap->rd_psp, pltptr, &pltptrval,
121 		    sizeof (long long)) != PS_OK) {
122 			LOG(ps_plog(MSG_ORIG(MSG_DB_READFAIL_2),
123 				EC_ADDR(pltptr)));
124 			return (RD_ERR);
125 		}
126 		pltptrval += pltaddr + 4;
127 		if (pltptrval == pltbase) {
128 			if ((rerr = rd_binder_exit_addr(rap,
129 			    MSG_ORIG(MSG_SYM_RTBIND),
130 			    &(rpi->pi_target))) != RD_OK) {
131 				return (rerr);
132 			}
133 			rpi->pi_skip_method = RD_RESOLVE_TARGET_STEP;
134 			rpi->pi_nstep = 1;
135 		} else {
136 			rpi->pi_skip_method = RD_RESOLVE_STEP;
137 			rpi->pi_nstep = 6;
138 			rpi->pi_target = 0;
139 			if (rtld_db_version >= RD_VERSION3) {
140 				destaddr = pltptrval;
141 				pltbound++;
142 			}
143 		}
144 	} else  {
145 		psaddr_t	pltaddr;
146 
147 		pltaddr = pltbase +
148 			((pltoff / M64_PLT_ENTSIZE) * M64_PLT_ENTSIZE);
149 
150 		if (ps_pread(rap->rd_psp, pltaddr, (char *)instr,
151 		    M64_PLT_ENTSIZE) != PS_OK) {
152 			LOG(ps_plog(MSG_ORIG(MSG_DB_READFAIL_2),
153 				EC_ADDR(pltaddr)));
154 			return (RD_ERR);
155 
156 		}
157 		/*
158 		 * ELF64 NEAR PLT's
159 		 */
160 		if ((instr[0] != M_NOP) &&
161 		    ((instr[1] & (~(S_MASK(19)))) == M_BA_A_XCC)) {
162 			/*
163 			 * Unbound PLT
164 			 */
165 			if ((rerr = rd_binder_exit_addr(rap,
166 			    MSG_ORIG(MSG_SYM_RTBIND),
167 			    &(rpi->pi_target))) != RD_OK) {
168 				return (rerr);
169 			}
170 			rpi->pi_skip_method = RD_RESOLVE_TARGET_STEP;
171 			rpi->pi_nstep = 1;
172 		} else  if ((instr[0] == M_NOP) &&
173 		    ((instr[1] & (~(S_MASK(22)))) == M_BA_A)) {
174 			/*
175 			 * Resolved 64-bit PLT entry format (b+-8mb):
176 			 * .PLT
177 			 * 0	nop
178 			 * 1	ba,a	<dest>
179 			 * 2	nop
180 			 * 3	nop
181 			 * 4	nop
182 			 * 5	nop
183 			 * 6	nop
184 			 * 7	nop
185 			 */
186 			rpi->pi_skip_method = RD_RESOLVE_STEP;
187 			rpi->pi_nstep = 2;
188 			rpi->pi_target = 0;
189 			if (rtld_db_version >= RD_VERSION3) {
190 				uint_t	d22;
191 				d22 = instr[1] & S_MASK(22);
192 				/* LINTED */
193 				destaddr = ((long)pltaddr + 4) +
194 					/* LINTED */
195 					(((int)d22 << 10) >> 8);
196 				pltbound++;
197 			}
198 		} else if ((instr[0] == M_NOP) &&
199 		    ((instr[1] & (~(S_MASK(19)))) == M_BA_A_PT)) {
200 			/*
201 			 * Resolved 64-bit PLT entry format (b+-2mb):
202 			 * .PLT
203 			 * 0	nop
204 			 * 1	ba,a,pt	%icc, <dest>
205 			 * 2	nop
206 			 * 3	nop
207 			 * 4	nop
208 			 * 5	nop
209 			 * 6	nop
210 			 * 7	nop
211 			 */
212 			rpi->pi_skip_method = RD_RESOLVE_STEP;
213 			rpi->pi_nstep = 2;
214 			rpi->pi_target = 0;
215 			if (rtld_db_version >= RD_VERSION3) {
216 				uint_t	d19;
217 				d19 = instr[1] & S_MASK(22);
218 				/* LINTED */
219 				destaddr = ((long)pltaddr + 4) +
220 					/* LINTED */
221 					(((int)d19 << 13) >> 11);
222 				pltbound++;
223 			}
224 		} else if ((instr[6] & (~(S_MASK(13)))) == M_JMPL_G5G0) {
225 			/*
226 			 * Resolved 64-bit PLT entry format (abs-64):
227 			 * .PLT
228 			 * 0	nop
229 			 * 1	sethi	%hh(dest), %g1
230 			 * 2	sethi	%lm(dest), %g5
231 			 * 3	or	%g1, %hm(dest), %g1
232 			 * 4	sllx	%g1, 32, %g1
233 			 * 5	or	%g1, %g5, %g5
234 			 * 6	jmpl	%g5 + %lo(dest), %g0
235 			 * 7	nop
236 			 */
237 			rpi->pi_skip_method = RD_RESOLVE_STEP;
238 			rpi->pi_nstep = 8;
239 			rpi->pi_target = 0;
240 			if (rtld_db_version >= RD_VERSION3) {
241 				uintptr_t	hh_bits;
242 				uintptr_t	hm_bits;
243 				uintptr_t	lm_bits;
244 				uintptr_t	lo_bits;
245 				hh_bits = instr[1] & S_MASK(22); /* 63..42 */
246 				hm_bits = instr[3] & S_MASK(10); /* 41..32 */
247 				lm_bits = instr[2] & S_MASK(22); /* 31..10 */
248 				lo_bits = instr[6] & S_MASK(10); /* 09..00 */
249 				destaddr = (hh_bits << 42) | (hm_bits << 32) |
250 					(lm_bits << 10) | lo_bits;
251 				pltbound++;
252 			}
253 		} else if (instr[3] == M_JMPL) {
254 			/*
255 			 * Resolved 64-bit PLT entry format (top-32):
256 			 *
257 			 * .PLT:
258 			 * 0	nop
259 			 * 1	sethi	%hi(~dest), %g5
260 			 * 2	xnor	%g5, %lo(~dest), %g1
261 			 * 3	jmpl	%g1, %g0
262 			 * 4	nop
263 			 * 5	nop
264 			 * 6	nop
265 			 * 7	nop
266 			 */
267 			rpi->pi_skip_method = RD_RESOLVE_STEP;
268 			rpi->pi_nstep = 5;
269 			rpi->pi_target = 0;
270 			if (rtld_db_version >= RD_VERSION3) {
271 				uintptr_t hi_bits;
272 				uintptr_t lo_bits;
273 				hi_bits = (instr[1] & S_MASK(22)) << 10;
274 				lo_bits = (instr[2] & S_MASK(10));
275 				destaddr = hi_bits ^ ~lo_bits;
276 				pltbound++;
277 			}
278 		} else if ((instr[2] & (~(S_MASK(13)))) == M_XNOR_G5G1) {
279 			/*
280 			 * Resolved 64-bit PLT entry format (top-44):
281 			 *
282 			 * .PLT:
283 			 * 0	nop
284 			 * 1	sethi	%h44(~dest), %g5
285 			 * 2	xnor	%g5, %m44(~dest), %g1
286 			 * 3	slxx	%g1, 12, %g1
287 			 * 4	jmpl %g1 + %l44(dest), %g0
288 			 * 5	nop
289 			 * 6	nop
290 			 * 7	nop
291 			 */
292 			rpi->pi_skip_method = RD_RESOLVE_STEP;
293 			rpi->pi_nstep = 6;
294 			rpi->pi_target = 0;
295 			if (rtld_db_version >= RD_VERSION3) {
296 				uintptr_t h44_bits;
297 				uintptr_t	m44_bits;
298 				uintptr_t	l44_bits;
299 				h44_bits = (((long)instr[1] & S_MASK(22))
300 					<< 10);
301 				m44_bits = (((long)instr[2] & S_MASK(13))
302 					<< 41) >> 41;
303 				l44_bits = (((long)instr[4] & S_MASK(13))
304 					<< 41) >> 41;
305 				destaddr = (~(h44_bits ^ m44_bits) << 12)
306 					+ l44_bits;
307 				pltbound++;
308 			}
309 		} else
310 			rpi->pi_skip_method = RD_RESOLVE_NONE;
311 	}
312 
313 	if ((rtld_db_version >= RD_VERSION3) && pltbound) {
314 		rpi->pi_flags |= RD_FLG_PI_PLTBOUND;
315 		rpi->pi_baddr = destaddr;
316 	}
317 
318 	return (RD_OK);
319 }
320