xref: /freebsd/sys/compat/ia32/ia32_sysvec.c (revision c4f6a2a9e1b1879b618c436ab4f56ff75c73a0f5)
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 	0,
97 	0,
98 	0,
99 	0,
100 	elf32_freebsd_fixup,
101 	sendsig,
102 	ia32_sigcode,
103 	&ia32_szsigcode,
104 	0,
105 	"FreeBSD ELF",
106 	elf32_coredump,
107 	NULL,
108 	MINSIGSTKSZ,
109 	4096,
110 	IA32_USRSTACK,
111 	IA32_USRSTACK,
112 	ia32_copyout_strings,
113 	ia32_setregs
114 };
115 
116 static Elf32_Brandinfo ia32_brand_info = {
117 						ELFOSABI_FREEBSD,
118 						EM_386,
119 						"FreeBSD",
120 						"/compat/ia32",
121 						"/usr/libexec/ld-elf.so.1",
122 						&ia32_freebsd_sysvec
123 					  };
124 
125 SYSINIT(ia32, SI_SUB_EXEC, SI_ORDER_ANY,
126 	(sysinit_cfunc_t) elf32_insert_brand_entry,
127 	&ia32_brand_info);
128 
129 static register_t *
130 ia32_copyout_strings(struct image_params *imgp)
131 {
132 	int argc, envc;
133 	u_int32_t *vectp;
134 	char *stringp, *destp;
135 	u_int32_t *stack_base;
136 	struct ia32_ps_strings *arginfo;
137 	int szsigcode;
138 
139 	/*
140 	 * Calculate string base and vector table pointers.
141 	 * Also deal with signal trampoline code for this exec type.
142 	 */
143 	arginfo = (struct ia32_ps_strings *)IA32_PS_STRINGS;
144 	szsigcode = *(imgp->proc->p_sysent->sv_szsigcode);
145 	destp =	(caddr_t)arginfo - szsigcode - SPARE_USRSPACE -
146 		roundup((ARG_MAX - imgp->stringspace), sizeof(char *));
147 
148 	/*
149 	 * install sigcode
150 	 */
151 	if (szsigcode)
152 		copyout(imgp->proc->p_sysent->sv_sigcode,
153 			((caddr_t)arginfo - szsigcode), szsigcode);
154 
155 	/*
156 	 * If we have a valid auxargs ptr, prepare some room
157 	 * on the stack.
158 	 */
159 	if (imgp->auxargs) {
160 		/*
161 		 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for
162 		 * lower compatibility.
163 		 */
164 		imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size
165 			: (AT_COUNT * 2);
166 		/*
167 		 * The '+ 2' is for the null pointers at the end of each of
168 		 * the arg and env vector sets,and imgp->auxarg_size is room
169 		 * for argument of Runtime loader.
170 		 */
171 		vectp = (u_int32_t *) (destp - (imgp->argc + imgp->envc + 2 +
172 				       imgp->auxarg_size) * sizeof(u_int32_t));
173 
174 	} else
175 		/*
176 		 * The '+ 2' is for the null pointers at the end of each of
177 		 * the arg and env vector sets
178 		 */
179 		vectp = (u_int32_t *)
180 			(destp - (imgp->argc + imgp->envc + 2) * sizeof(u_int32_t));
181 
182 	/*
183 	 * vectp also becomes our initial stack base
184 	 */
185 	stack_base = vectp;
186 
187 	stringp = imgp->stringbase;
188 	argc = imgp->argc;
189 	envc = imgp->envc;
190 
191 	/*
192 	 * Copy out strings - arguments and environment.
193 	 */
194 	copyout(stringp, destp, ARG_MAX - imgp->stringspace);
195 
196 	/*
197 	 * Fill in "ps_strings" struct for ps, w, etc.
198 	 */
199 	suword32(&arginfo->ps_argvstr, (u_int32_t)(intptr_t)vectp);
200 	suword32(&arginfo->ps_nargvstr, argc);
201 
202 	/*
203 	 * Fill in argument portion of vector table.
204 	 */
205 	for (; argc > 0; --argc) {
206 		suword32(vectp++, (u_int32_t)(intptr_t)destp);
207 		while (*stringp++ != 0)
208 			destp++;
209 		destp++;
210 	}
211 
212 	/* a null vector table pointer separates the argp's from the envp's */
213 	suword32(vectp++, 0);
214 
215 	suword32(&arginfo->ps_envstr, (u_int32_t)(intptr_t)vectp);
216 	suword32(&arginfo->ps_nenvstr, envc);
217 
218 	/*
219 	 * Fill in environment portion of vector table.
220 	 */
221 	for (; envc > 0; --envc) {
222 		suword32(vectp++, (u_int32_t)(intptr_t)destp);
223 		while (*stringp++ != 0)
224 			destp++;
225 		destp++;
226 	}
227 
228 	/* end of vector table is a null pointer */
229 	suword32(vectp, 0);
230 
231 	return ((register_t *)stack_base);
232 }
233 
234 static void
235 ia32_setregs(struct thread *td, u_long entry, u_long stack, u_long ps_strings)
236 {
237 	struct trapframe *frame = td->td_frame;
238 	vm_offset_t gdt, ldt;
239 	u_int64_t codesel, datasel, ldtsel;
240 	u_int64_t codeseg, dataseg, gdtseg, ldtseg;
241 	struct segment_descriptor desc;
242 	struct vmspace *vmspace = td->td_proc->p_vmspace;
243 
244 	/*
245 	 * Make sure that we restore the entire trapframe after an
246 	 * execve.
247 	 */
248 	frame->tf_flags &= ~FRAME_SYSCALL;
249 
250 	bzero(frame->tf_r, sizeof(frame->tf_r));
251 	bzero(frame->tf_f, sizeof(frame->tf_f));
252 
253 	frame->tf_cr_iip = entry;
254 	frame->tf_cr_ipsr = (IA64_PSR_IC
255 			     | IA64_PSR_I
256 			     | IA64_PSR_IT
257 			     | IA64_PSR_DT
258 			     | IA64_PSR_RT
259 			     | IA64_PSR_DFH
260 			     | IA64_PSR_IS
261 			     | IA64_PSR_BN
262 			     | IA64_PSR_CPL_USER);
263 	frame->tf_r[FRAME_R12] = stack;
264 
265 	codesel = LSEL(LUCODE_SEL, SEL_UPL);
266 	datasel = LSEL(LUDATA_SEL, SEL_UPL);
267 	ldtsel = GSEL(GLDT_SEL, SEL_UPL);
268 
269 #if 1
270 	frame->tf_r[FRAME_R16] = (datasel << 48) | (datasel << 32)
271 		| (datasel << 16) | datasel;
272 	frame->tf_r[FRAME_R17] = (ldtsel << 32) | (datasel << 16) | codesel;
273 #else
274 	frame->tf_r[FRAME_R16] = datasel;
275 	frame->tf_r[FRAME_R17] = codesel;
276 	frame->tf_r[FRAME_R18] = datasel;
277 	frame->tf_r[FRAME_R19] = datasel;
278 	frame->tf_r[FRAME_R20] = datasel;
279 	frame->tf_r[FRAME_R21] = datasel;
280 	frame->tf_r[FRAME_R22] = ldtsel;
281 #endif
282 
283 	/*
284 	 * Build the GDT and LDT.
285 	 */
286 	gdt = IA32_USRSTACK;
287 	vm_map_find(&vmspace->vm_map, 0, 0,
288 		    &gdt, PAGE_SIZE, 0,
289 		    VM_PROT_ALL, VM_PROT_ALL, 0);
290 	ldt = gdt + 4096;
291 
292 	desc.sd_lolimit = 8*NLDT-1;
293 	desc.sd_lobase = ldt & 0xffffff;
294 	desc.sd_type = SDT_SYSLDT;
295 	desc.sd_dpl = SEL_UPL;
296 	desc.sd_p = 1;
297 	desc.sd_hilimit = 0;
298 	desc.sd_def32 = 0;
299 	desc.sd_gran = 0;
300 	desc.sd_hibase = ldt >> 24;
301 	copyout(&desc, (caddr_t) gdt + 8*GLDT_SEL, sizeof(desc));
302 
303 	desc.sd_lolimit = ((IA32_USRSTACK >> 12) - 1) & 0xffff;
304 	desc.sd_lobase = 0;
305 	desc.sd_type = SDT_MEMERA;
306 	desc.sd_dpl = SEL_UPL;
307 	desc.sd_p = 1;
308 	desc.sd_hilimit = ((IA32_USRSTACK >> 12) - 1) >> 16;
309 	desc.sd_def32 = 1;
310 	desc.sd_gran = 1;
311 	desc.sd_hibase = 0;
312 	copyout(&desc, (caddr_t) ldt + 8*LUCODE_SEL, sizeof(desc));
313 	desc.sd_type = SDT_MEMRWA;
314 	copyout(&desc, (caddr_t) ldt + 8*LUDATA_SEL, sizeof(desc));
315 
316 	codeseg = 0		/* base */
317 		+ (((IA32_USRSTACK >> 12) - 1) << 32) /* limit */
318 		+ ((long)SDT_MEMERA << 52)
319 		+ ((long)SEL_UPL << 57)
320 		+ (1L << 59) /* present */
321 		+ (1L << 62) /* 32 bits */
322 		+ (1L << 63); /* page granularity */
323 	dataseg = 0		/* base */
324 		+ (((IA32_USRSTACK >> 12) - 1) << 32) /* limit */
325 		+ ((long)SDT_MEMRWA << 52)
326 		+ ((long)SEL_UPL << 57)
327 		+ (1L << 59) /* present */
328 		+ (1L << 62) /* 32 bits */
329 		+ (1L << 63); /* page granularity */
330 	ia64_set_csd(codeseg);
331 	ia64_set_ssd(dataseg);
332 	frame->tf_r[FRAME_R24] = dataseg; /* ESD */
333 	frame->tf_r[FRAME_R27] = dataseg; /* DSD */
334 	frame->tf_r[FRAME_R28] = dataseg; /* FSD */
335 	frame->tf_r[FRAME_R29] = dataseg; /* GSD */
336 
337 	gdtseg = gdt		/* base */
338 		+ ((8L*NGDT - 1) << 32) /* limit */
339 		+ ((long)SDT_SYSNULL << 52)
340 		+ ((long)SEL_UPL << 57)
341 		+ (1L << 59) /* present */
342 		+ (0L << 62) /* 16 bits */
343 		+ (0L << 63); /* byte granularity */
344 	ldtseg = ldt		/* base */
345 		+ ((8L*NLDT - 1) << 32) /* limit */
346 		+ ((long)SDT_SYSLDT << 52)
347 		+ ((long)SEL_UPL << 57)
348 		+ (1L << 59) /* present */
349 		+ (0L << 62) /* 16 bits */
350 		+ (0L << 63); /* byte granularity */
351 	frame->tf_r[FRAME_R30] = ldtseg; /* LDTD */
352 	frame->tf_r[FRAME_R31] = gdtseg; /* GDTD */
353 
354 	ia64_set_eflag(PSL_USER);
355 
356 	/* PS_STRINGS value for BSD/OS binaries.  It is 0 for non-BSD/OS. */
357 	frame->tf_r[FRAME_R11] = IA32_PS_STRINGS;
358 
359 	/*
360 	 * XXX - Linux emulator
361 	 * Make sure sure edx is 0x0 on entry. Linux binaries depend
362 	 * on it.
363 	 */
364 	td->td_retval[1] = 0;
365 }
366