xref: /freebsd/sys/compat/ia32/ia32_sysvec.c (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
1 /*-
2  * Copyright (c) 2002 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #define __ELF_WORD_SIZE 32
30 
31 #include <sys/param.h>
32 #include <sys/exec.h>
33 #include <sys/fcntl.h>
34 #include <sys/imgact.h>
35 #include <sys/kernel.h>
36 #include <sys/lock.h>
37 #include <sys/malloc.h>
38 #include <sys/mutex.h>
39 #include <sys/mman.h>
40 #include <sys/namei.h>
41 #include <sys/pioctl.h>
42 #include <sys/proc.h>
43 #include <sys/procfs.h>
44 #include <sys/resourcevar.h>
45 #include <sys/systm.h>
46 #include <sys/signalvar.h>
47 #include <sys/stat.h>
48 #include <sys/sx.h>
49 #include <sys/syscall.h>
50 #include <sys/sysctl.h>
51 #include <sys/sysent.h>
52 #include <sys/vnode.h>
53 #include <sys/imgact_elf.h>
54 
55 #include <vm/vm.h>
56 #include <vm/vm_kern.h>
57 #include <vm/vm_param.h>
58 #include <vm/pmap.h>
59 #include <vm/vm_map.h>
60 #include <vm/vm_object.h>
61 #include <vm/vm_extern.h>
62 
63 #include <ia64/ia32/ia32_util.h>
64 #include <i386/include/psl.h>
65 #include <i386/include/segments.h>
66 #include <i386/include/specialreg.h>
67 #include <machine/frame.h>
68 #include <machine/md_var.h>
69 
70 static register_t *ia32_copyout_strings(struct image_params *imgp);
71 static void ia32_setregs(struct thread *td, u_long entry, u_long stack,
72     u_long ps_strings);
73 
74 extern struct sysent ia32_sysent[];
75 
76 static char ia32_sigcode[] = {
77 	0xff, 0x54, 0x24, 0x10,		/* call *SIGF_HANDLER(%esp) */
78 	0x8d, 0x44, 0x24, 0x14,		/* lea SIGF_UC(%esp),%eax */
79 	0x50,				/* pushl %eax */
80 	0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x02, /* testl $PSL_VM,UC_EFLAGS(%eax) */
81 	0x75, 0x03,			/* jne 9f */
82 	0x8e, 0x68, 0x14,		/* movl UC_GS(%eax),%gs */
83 	0xb8, 0x57, 0x01, 0x00, 0x00,	/* 9: movl $SYS_sigreturn,%eax */
84 	0x50,				/* pushl %eax */
85 	0xcd, 0x80,			/* int $0x80 */
86 	0xeb, 0xfe,			/* 0: jmp 0b */
87 	0, 0, 0, 0
88 };
89 static int ia32_szsigcode = sizeof(ia32_sigcode) & ~3;
90 
91 struct sysentvec ia32_freebsd_sysvec = {
92 	SYS_MAXSYSCALL,
93 	ia32_sysent,
94 	0,
95 	0,
96 	NULL,
97 	0,
98 	NULL,
99 	NULL,
100 	elf32_freebsd_fixup,
101 	sendsig,
102 	ia32_sigcode,
103 	&ia32_szsigcode,
104 	NULL,
105 	"FreeBSD ELF",
106 	elf32_coredump,
107 	NULL,
108 	MINSIGSTKSZ,
109 	4096,
110 	0,
111 	IA32_USRSTACK,
112 	IA32_USRSTACK,
113 	IA32_PS_STRINGS,
114 	VM_PROT_ALL,
115 	ia32_copyout_strings,
116 	ia32_setregs
117 };
118 
119 static Elf32_Brandinfo ia32_brand_info = {
120 						ELFOSABI_FREEBSD,
121 						EM_386,
122 						"FreeBSD",
123 						"/compat/ia32",
124 						"/usr/libexec/ld-elf.so.1",
125 						&ia32_freebsd_sysvec
126 					  };
127 
128 SYSINIT(ia32, SI_SUB_EXEC, SI_ORDER_ANY,
129 	(sysinit_cfunc_t) elf32_insert_brand_entry,
130 	&ia32_brand_info);
131 
132 static register_t *
133 ia32_copyout_strings(struct image_params *imgp)
134 {
135 	int argc, envc;
136 	u_int32_t *vectp;
137 	char *stringp, *destp;
138 	u_int32_t *stack_base;
139 	struct ia32_ps_strings *arginfo;
140 	int szsigcode;
141 
142 	/*
143 	 * Calculate string base and vector table pointers.
144 	 * Also deal with signal trampoline code for this exec type.
145 	 */
146 	arginfo = (struct ia32_ps_strings *)IA32_PS_STRINGS;
147 	szsigcode = *(imgp->proc->p_sysent->sv_szsigcode);
148 	destp =	(caddr_t)arginfo - szsigcode - SPARE_USRSPACE -
149 		roundup((ARG_MAX - imgp->stringspace), sizeof(char *));
150 
151 	/*
152 	 * install sigcode
153 	 */
154 	if (szsigcode)
155 		copyout(imgp->proc->p_sysent->sv_sigcode,
156 			((caddr_t)arginfo - szsigcode), szsigcode);
157 
158 	/*
159 	 * If we have a valid auxargs ptr, prepare some room
160 	 * on the stack.
161 	 */
162 	if (imgp->auxargs) {
163 		/*
164 		 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for
165 		 * lower compatibility.
166 		 */
167 		imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size
168 			: (AT_COUNT * 2);
169 		/*
170 		 * The '+ 2' is for the null pointers at the end of each of
171 		 * the arg and env vector sets,and imgp->auxarg_size is room
172 		 * for argument of Runtime loader.
173 		 */
174 		vectp = (u_int32_t *) (destp - (imgp->argc + imgp->envc + 2 +
175 				       imgp->auxarg_size) * sizeof(u_int32_t));
176 
177 	} else
178 		/*
179 		 * The '+ 2' is for the null pointers at the end of each of
180 		 * the arg and env vector sets
181 		 */
182 		vectp = (u_int32_t *)
183 			(destp - (imgp->argc + imgp->envc + 2) * sizeof(u_int32_t));
184 
185 	/*
186 	 * vectp also becomes our initial stack base
187 	 */
188 	stack_base = vectp;
189 
190 	stringp = imgp->stringbase;
191 	argc = imgp->argc;
192 	envc = imgp->envc;
193 
194 	/*
195 	 * Copy out strings - arguments and environment.
196 	 */
197 	copyout(stringp, destp, ARG_MAX - imgp->stringspace);
198 
199 	/*
200 	 * Fill in "ps_strings" struct for ps, w, etc.
201 	 */
202 	suword32(&arginfo->ps_argvstr, (u_int32_t)(intptr_t)vectp);
203 	suword32(&arginfo->ps_nargvstr, argc);
204 
205 	/*
206 	 * Fill in argument portion of vector table.
207 	 */
208 	for (; argc > 0; --argc) {
209 		suword32(vectp++, (u_int32_t)(intptr_t)destp);
210 		while (*stringp++ != 0)
211 			destp++;
212 		destp++;
213 	}
214 
215 	/* a null vector table pointer separates the argp's from the envp's */
216 	suword32(vectp++, 0);
217 
218 	suword32(&arginfo->ps_envstr, (u_int32_t)(intptr_t)vectp);
219 	suword32(&arginfo->ps_nenvstr, envc);
220 
221 	/*
222 	 * Fill in environment portion of vector table.
223 	 */
224 	for (; envc > 0; --envc) {
225 		suword32(vectp++, (u_int32_t)(intptr_t)destp);
226 		while (*stringp++ != 0)
227 			destp++;
228 		destp++;
229 	}
230 
231 	/* end of vector table is a null pointer */
232 	suword32(vectp, 0);
233 
234 	return ((register_t *)stack_base);
235 }
236 
237 static void
238 ia32_setregs(struct thread *td, u_long entry, u_long stack, u_long ps_strings)
239 {
240 	struct trapframe *frame = td->td_frame;
241 	vm_offset_t gdt, ldt;
242 	u_int64_t codesel, datasel, ldtsel;
243 	u_int64_t codeseg, dataseg, gdtseg, ldtseg;
244 	struct segment_descriptor desc;
245 	struct vmspace *vmspace = td->td_proc->p_vmspace;
246 
247 	/*
248 	 * Make sure that we restore the entire trapframe after an
249 	 * execve.
250 	 */
251 	frame->tf_flags &= ~FRAME_SYSCALL;
252 
253 	bzero(frame->tf_r, sizeof(frame->tf_r));
254 	bzero(frame->tf_f, sizeof(frame->tf_f));
255 
256 	frame->tf_cr_iip = entry;
257 	frame->tf_cr_ipsr = (IA64_PSR_IC
258 			     | IA64_PSR_I
259 			     | IA64_PSR_IT
260 			     | IA64_PSR_DT
261 			     | IA64_PSR_RT
262 			     | IA64_PSR_DFH
263 			     | IA64_PSR_IS
264 			     | IA64_PSR_BN
265 			     | IA64_PSR_CPL_USER);
266 	frame->tf_r[FRAME_R12] = stack;
267 
268 	codesel = LSEL(LUCODE_SEL, SEL_UPL);
269 	datasel = LSEL(LUDATA_SEL, SEL_UPL);
270 	ldtsel = GSEL(GLDT_SEL, SEL_UPL);
271 
272 #if 1
273 	frame->tf_r[FRAME_R16] = (datasel << 48) | (datasel << 32)
274 		| (datasel << 16) | datasel;
275 	frame->tf_r[FRAME_R17] = (ldtsel << 32) | (datasel << 16) | codesel;
276 #else
277 	frame->tf_r[FRAME_R16] = datasel;
278 	frame->tf_r[FRAME_R17] = codesel;
279 	frame->tf_r[FRAME_R18] = datasel;
280 	frame->tf_r[FRAME_R19] = datasel;
281 	frame->tf_r[FRAME_R20] = datasel;
282 	frame->tf_r[FRAME_R21] = datasel;
283 	frame->tf_r[FRAME_R22] = ldtsel;
284 #endif
285 
286 	/*
287 	 * Build the GDT and LDT.
288 	 */
289 	gdt = IA32_USRSTACK;
290 	vm_map_find(&vmspace->vm_map, 0, 0,
291 		    &gdt, PAGE_SIZE, 0,
292 		    VM_PROT_ALL, VM_PROT_ALL, 0);
293 	ldt = gdt + 4096;
294 
295 	desc.sd_lolimit = 8*NLDT-1;
296 	desc.sd_lobase = ldt & 0xffffff;
297 	desc.sd_type = SDT_SYSLDT;
298 	desc.sd_dpl = SEL_UPL;
299 	desc.sd_p = 1;
300 	desc.sd_hilimit = 0;
301 	desc.sd_def32 = 0;
302 	desc.sd_gran = 0;
303 	desc.sd_hibase = ldt >> 24;
304 	copyout(&desc, (caddr_t) gdt + 8*GLDT_SEL, sizeof(desc));
305 
306 	desc.sd_lolimit = ((IA32_USRSTACK >> 12) - 1) & 0xffff;
307 	desc.sd_lobase = 0;
308 	desc.sd_type = SDT_MEMERA;
309 	desc.sd_dpl = SEL_UPL;
310 	desc.sd_p = 1;
311 	desc.sd_hilimit = ((IA32_USRSTACK >> 12) - 1) >> 16;
312 	desc.sd_def32 = 1;
313 	desc.sd_gran = 1;
314 	desc.sd_hibase = 0;
315 	copyout(&desc, (caddr_t) ldt + 8*LUCODE_SEL, sizeof(desc));
316 	desc.sd_type = SDT_MEMRWA;
317 	copyout(&desc, (caddr_t) ldt + 8*LUDATA_SEL, sizeof(desc));
318 
319 	codeseg = 0		/* base */
320 		+ (((IA32_USRSTACK >> 12) - 1) << 32) /* limit */
321 		+ ((long)SDT_MEMERA << 52)
322 		+ ((long)SEL_UPL << 57)
323 		+ (1L << 59) /* present */
324 		+ (1L << 62) /* 32 bits */
325 		+ (1L << 63); /* page granularity */
326 	dataseg = 0		/* base */
327 		+ (((IA32_USRSTACK >> 12) - 1) << 32) /* limit */
328 		+ ((long)SDT_MEMRWA << 52)
329 		+ ((long)SEL_UPL << 57)
330 		+ (1L << 59) /* present */
331 		+ (1L << 62) /* 32 bits */
332 		+ (1L << 63); /* page granularity */
333 	ia64_set_csd(codeseg);
334 	ia64_set_ssd(dataseg);
335 	frame->tf_r[FRAME_R24] = dataseg; /* ESD */
336 	frame->tf_r[FRAME_R27] = dataseg; /* DSD */
337 	frame->tf_r[FRAME_R28] = dataseg; /* FSD */
338 	frame->tf_r[FRAME_R29] = dataseg; /* GSD */
339 
340 	gdtseg = gdt		/* base */
341 		+ ((8L*NGDT - 1) << 32) /* limit */
342 		+ ((long)SDT_SYSNULL << 52)
343 		+ ((long)SEL_UPL << 57)
344 		+ (1L << 59) /* present */
345 		+ (0L << 62) /* 16 bits */
346 		+ (0L << 63); /* byte granularity */
347 	ldtseg = ldt		/* base */
348 		+ ((8L*NLDT - 1) << 32) /* limit */
349 		+ ((long)SDT_SYSLDT << 52)
350 		+ ((long)SEL_UPL << 57)
351 		+ (1L << 59) /* present */
352 		+ (0L << 62) /* 16 bits */
353 		+ (0L << 63); /* byte granularity */
354 	frame->tf_r[FRAME_R30] = ldtseg; /* LDTD */
355 	frame->tf_r[FRAME_R31] = gdtseg; /* GDTD */
356 
357 	ia64_set_eflag(PSL_USER);
358 
359 	/* PS_STRINGS value for BSD/OS binaries.  It is 0 for non-BSD/OS. */
360 	frame->tf_r[FRAME_R11] = IA32_PS_STRINGS;
361 
362 	/*
363 	 * XXX - Linux emulator
364 	 * Make sure sure edx is 0x0 on entry. Linux binaries depend
365 	 * on it.
366 	 */
367 	td->td_retval[1] = 0;
368 }
369