xref: /netbsd-src/sys/compat/netbsd32/netbsd32_exec_aout.c (revision 5aefcfdc06931dd97e76246d2fe0302f7b3fe094)
1 /*	$NetBSD: netbsd32_exec_aout.c,v 1.2 2000/12/18 14:50:04 mrg Exp $	*/
2 /*	from: NetBSD: exec_aout.c,v 1.15 1996/09/26 23:34:46 cgd Exp */
3 
4 /*
5  * Copyright (c) 1998 Matthew R. Green.
6  * Copyright (c) 1993, 1994 Christopher G. Demetriou
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed by Christopher G. Demetriou.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/proc.h>
38 #include <sys/malloc.h>
39 #include <sys/vnode.h>
40 #include <sys/exec.h>
41 #include <sys/resourcevar.h>
42 #include <sys/signal.h>
43 #include <sys/signalvar.h>
44 
45 #include <compat/netbsd32/netbsd32.h>
46 #ifndef EXEC_AOUT
47 #define EXEC_AOUT
48 #endif
49 #include <compat/netbsd32/netbsd32_exec.h>
50 
51 #include <machine/frame.h>
52 #include <machine/netbsd32_machdep.h>
53 
54 int netbsd32_copyinargs __P((struct exec_package *, struct ps_strings *,
55 			     void *, size_t, const void *, const void *));
56 
57 static int netbsd32_exec_aout_prep_zmagic __P((struct proc *,
58 					       struct exec_package *));
59 static int netbsd32_exec_aout_prep_nmagic __P((struct proc *,
60 					       struct exec_package *));
61 static int netbsd32_exec_aout_prep_omagic __P((struct proc *,
62 					       struct exec_package *));
63 int netbsd32_exec_aout_setup_stack __P((struct proc *p,
64 					struct exec_package *epp));
65 
66 /*
67  * exec_netbsd32_makecmds(): Check if it's an netbsd32 a.out format
68  * executable.
69  *
70  * Given a proc pointer and an exec package pointer, see if the referent
71  * of the epp is in netbsd32 a.out format.  Check 'standard' magic
72  * numbers for this architecture.
73  *
74  * This function, in the former case, or the hook, in the latter, is
75  * responsible for creating a set of vmcmds which can be used to build
76  * the process's vm space and inserting them into the exec package.
77  */
78 
79 int
80 exec_netbsd32_makecmds(p, epp)
81 	struct proc *p;
82 	struct exec_package *epp;
83 {
84 	netbsd32_u_long midmag, magic;
85 	u_short mid;
86 	int error;
87 	struct netbsd32_exec *execp = epp->ep_hdr;
88 
89 	if (epp->ep_hdrvalid < sizeof(struct netbsd32_exec))
90 		return ENOEXEC;
91 
92 	midmag = (netbsd32_u_long)ntohl(execp->a_midmag);
93 	mid = (midmag >> 16) & 0x3ff;
94 	magic = midmag & 0xffff;
95 
96 	midmag = mid << 16 | magic;
97 
98 	switch (midmag) {
99 	case (MID_SPARC << 16) | ZMAGIC:
100 		error = netbsd32_exec_aout_prep_zmagic(p, epp);
101 		break;
102 	case (MID_SPARC << 16) | NMAGIC:
103 		error = netbsd32_exec_aout_prep_nmagic(p, epp);
104 		break;
105 	case (MID_SPARC << 16) | OMAGIC:
106 		error = netbsd32_exec_aout_prep_omagic(p, epp);
107 		break;
108 	default:
109 		/* Invalid magic */
110 		error = ENOEXEC;
111 		break;
112 	}
113 
114 	if (error == 0) {
115 		/* set up our emulation information */
116 		epp->ep_flags |= EXEC_32;
117 	} else
118 		kill_vmcmds(&epp->ep_vmcmds);
119 
120 	return error;
121 }
122 
123 /*
124  * netbsd32_exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's
125  * exec package
126  *
127  * First, set of the various offsets/lengths in the exec package.
128  *
129  * Then, mark the text image busy (so it can be demand paged) or error
130  * out if this is not possible.  Finally, set up vmcmds for the
131  * text, data, bss, and stack segments.
132  */
133 
134 int
135 netbsd32_exec_aout_prep_zmagic(p, epp)
136 	struct proc *p;
137 	struct exec_package *epp;
138 {
139 	struct netbsd32_exec *execp = epp->ep_hdr;
140 
141 	epp->ep_taddr = USRTEXT;
142 	epp->ep_tsize = execp->a_text;
143 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
144 	epp->ep_dsize = execp->a_data + execp->a_bss;
145 	epp->ep_entry = execp->a_entry;
146 
147 	/*
148 	 * check if vnode is in open for writing, because we want to
149 	 * demand-page out of it.  if it is, don't do it, for various
150 	 * reasons
151 	 */
152 	if ((execp->a_text != 0 || execp->a_data != 0) &&
153 	    epp->ep_vp->v_writecount != 0) {
154 #ifdef DIAGNOSTIC
155 		if (epp->ep_vp->v_flag & VTEXT)
156 			panic("exec: a VTEXT vnode has writecount != 0\n");
157 #endif
158 		return ETXTBSY;
159 	}
160 	vn_marktext(epp->ep_vp);
161 
162 	/* set up command for text segment */
163 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
164 	    epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
165 
166 	/* set up command for data segment */
167 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
168 	    epp->ep_daddr, epp->ep_vp, execp->a_text,
169 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
170 
171 	/* set up command for bss segment */
172 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
173 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
174 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
175 
176 	return netbsd32_exec_aout_setup_stack(p, epp);
177 }
178 
179 /*
180  * netbsd32_exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's
181  * exec package
182  */
183 
184 int
185 netbsd32_exec_aout_prep_nmagic(p, epp)
186 	struct proc *p;
187 	struct exec_package *epp;
188 {
189 	struct netbsd32_exec *execp = epp->ep_hdr;
190 	long bsize, baddr;
191 
192 	epp->ep_taddr = USRTEXT;
193 	epp->ep_tsize = execp->a_text;
194 	epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, __LDPGSZ);
195 	epp->ep_dsize = execp->a_data + execp->a_bss;
196 	epp->ep_entry = execp->a_entry;
197 
198 	/* set up command for text segment */
199 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
200 	    epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
201 	    VM_PROT_READ|VM_PROT_EXECUTE);
202 
203 	/* set up command for data segment */
204 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
205 	    epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
206 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
207 
208 	/* set up command for bss segment */
209 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
210 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
211 	if (bsize > 0)
212 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
213 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
214 
215 	return netbsd32_exec_aout_setup_stack(p, epp);
216 }
217 
218 /*
219  * netbsd32_exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's
220  * exec package
221  */
222 
223 int
224 netbsd32_exec_aout_prep_omagic(p, epp)
225 	struct proc *p;
226 	struct exec_package *epp;
227 {
228 	struct netbsd32_exec *execp = epp->ep_hdr;
229 	long dsize, bsize, baddr;
230 
231 	epp->ep_taddr = USRTEXT;
232 	epp->ep_tsize = execp->a_text;
233 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
234 	epp->ep_dsize = execp->a_data + execp->a_bss;
235 	epp->ep_entry = execp->a_entry;
236 
237 	/* set up command for text and data segments */
238 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
239 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
240 	    sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
241 
242 	/* set up command for bss segment */
243 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
244 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
245 	if (bsize > 0)
246 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
247 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
248 
249 	/*
250 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
251 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
252 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
253 	 * respectively to page boundaries.
254 	 * Compensate `ep_dsize' for the amount of data covered by the last
255 	 * text page.
256 	 */
257 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
258 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
259 	return netbsd32_exec_aout_setup_stack(p, epp);
260 }
261 
262 /*
263  * netbsd32_exec_aout_setup_stack(): Set up the stack segment for an a.out
264  * executable.
265  *
266  * Note that the ep_ssize parameter must be set to be the current stack
267  * limit; this is adjusted in the body of execve() to yield the
268  * appropriate stack segment usage once the argument length is
269  * calculated.
270  *
271  * This function returns an int for uniformity with other (future) formats'
272  * stack setup functions.  They might have errors to return.
273  */
274 int
275 netbsd32_exec_aout_setup_stack(struct proc *p, struct exec_package *epp)
276 {
277 
278 	epp->ep_maxsaddr = USRSTACK32 - MAXSSIZ;
279 	epp->ep_minsaddr = USRSTACK32;
280 	epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur;
281 
282 	/*
283 	 * set up commands for stack.  note that this takes *two*, one to
284 	 * map the part of the stack which we can access, and one to map
285 	 * the part which we can't.
286 	 *
287 	 * arguably, it could be made into one, but that would require the
288 	 * addition of another mapping proc, which is unnecessary
289 	 *
290 	 * note that in memory, things assumed to be: 0 ... ep_maxsaddr
291 	 * <stack> ep_minsaddr
292 	 */
293 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
294 	    ((epp->ep_minsaddr - epp->ep_ssize) - epp->ep_maxsaddr),
295 	    epp->ep_maxsaddr, NULLVP, 0, VM_PROT_NONE);
296 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, epp->ep_ssize,
297 	    (epp->ep_minsaddr - epp->ep_ssize), NULLVP, 0,
298 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
299 
300 	return 0;
301 }
302