xref: /netbsd-src/sys/compat/freebsd/freebsd_exec.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: freebsd_exec.c,v 1.6 2000/06/28 15:39:26 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 1993, 1994 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Christopher G. Demetriou.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include "opt_execfmt.h"
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 #ifdef EXEC_ELF32
42 # ifndef ELFSIZE
43 #  define ELFSIZE 32
44 # endif /* !ELFSIZE */
45 # include <sys/exec_elf.h>
46 #endif /* EXEC_ELF32 */
47 #include <sys/resourcevar.h>
48 
49 #include <machine/freebsd_machdep.h>
50 
51 #include <compat/freebsd/freebsd_exec.h>
52 #include <compat/freebsd/freebsd_util.h>
53 
54 #include <compat/freebsd/freebsd_syscall.h>
55 
56 extern struct sysent freebsd_sysent[];
57 extern char *freebsd_syscallnames[];
58 
59 #ifdef EXEC_AOUT
60 struct emul emul_freebsd_aout = {
61 	"freebsd",
62 	NULL,
63 	freebsd_sendsig,
64 	FREEBSD_SYS_syscall,
65 	FREEBSD_SYS_MAXSYSCALL,
66 	freebsd_sysent,
67 	freebsd_syscallnames,
68 	0,
69 	copyargs,
70 	freebsd_setregs,
71 	freebsd_sigcode,
72 	freebsd_esigcode,
73 };
74 #endif /* EXEC_AOUT */
75 
76 #ifdef EXEC_ELF32
77 
78 struct emul ELFNAMEEND(emul_freebsd) = {
79 	"freebsd",
80 	NULL,
81 	freebsd_sendsig,
82 	FREEBSD_SYS_syscall,
83 	FREEBSD_SYS_MAXSYSCALL,
84 	freebsd_sysent,
85 	freebsd_syscallnames,
86 	FREEBSD_ELF_AUX_ARGSIZ,
87 	ELFNAME(copyargs),
88 	freebsd_setregs,
89 	freebsd_sigcode,
90 	freebsd_esigcode,
91 };
92 
93 int
94 ELFNAME2(freebsd,probe)(p, epp, eh, itp, pos)
95 	struct proc *p;
96 	struct exec_package *epp;
97 	Elf_Ehdr *eh;
98 	char *itp;
99 	Elf_Addr *pos;
100 {
101 	int error;
102 	size_t i;
103 	size_t phsize;
104 	Elf_Phdr *ph;
105 	Elf_Phdr *ephp;
106 	Elf_Nhdr *np;
107 	const char *bp;
108 
109         static const char wantBrand[] = FREEBSD_ELF_BRAND_STRING;
110         static const char wantInterp[] = FREEBSD_ELF_INTERP_PREFIX_STRING;
111 
112         /* Insist that the executable have a brand, and that it be "FreeBSD" */
113 #ifndef EI_BRAND
114 #define EI_BRAND 8
115 #endif
116         if (eh->e_ident[EI_BRAND] == '\0'
117 	  || strcmp(&eh->e_ident[EI_BRAND], wantBrand))
118 		return ENOEXEC;
119 
120 	i = eh->e_phnum;
121 	if (i != 0) {
122 		phsize = i * sizeof(Elf_Phdr);
123 		ph = (Elf_Phdr *) malloc(phsize, M_TEMP, M_WAITOK);
124 		if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_phoff,
125 		    (caddr_t) ph, phsize)) != 0)
126 			goto bad1;
127 
128 		for (ephp = ph; i--; ephp++) {
129 			if (ephp->p_type != PT_INTERP)
130 				continue;
131 
132 			/* Check for "legal" intepreter name. */
133 			if (ephp->p_filesz < sizeof wantInterp)
134 				goto bad1;
135 
136 			np = (Elf_Nhdr *) malloc(ephp->p_filesz+1,
137 			    M_TEMP, M_WAITOK);
138 
139 			if (((error = ELFNAME(read_from)(p, epp->ep_vp,
140 			    ephp->p_offset, (caddr_t)np, ephp->p_filesz)) != 0))
141 				goto bad2;
142 
143 			if (strncmp((char *)np, wantInterp,
144 			    sizeof wantInterp - 1))
145 				goto bad2;
146 
147 			free(np, M_TEMP);
148 			break;
149 		}
150 		free(ph, M_TEMP);
151 	}
152 
153 	if (itp[0]) {
154 		if ((error = emul_find(p, NULL, freebsd_emul_path,
155 		    itp, &bp, 0)))
156 			return error;
157 		if ((error = copystr(bp, itp, MAXPATHLEN, &i)) != 0)
158 			return error;
159 		free((void *)bp, M_TEMP);
160 	}
161 	epp->ep_emul = &ELFNAMEEND(emul_freebsd);
162 	*pos = ELF_NO_ADDR;
163 #ifdef DEBUG_FREEBSD_ELF
164 	printf("freebsd_elf32_probe: returning 0\n");
165 #endif
166 	return 0;
167 
168 bad2:
169 	free(np, M_TEMP);
170 bad1:
171 	free(ph, M_TEMP);
172 	return ENOEXEC;
173 }
174 #endif /* EXEC_ELF32 */
175 
176 
177 #ifdef EXEC_AOUT
178 /*
179 * exec_aout_makecmds(): Check if it's an a.out-format executable.
180 *
181 * Given a proc pointer and an exec package pointer, see if the referent
182 * of the epp is in a.out format.  First check 'standard' magic numbers for
183 * this architecture.  If that fails, try a cpu-dependent hook.
184  *
185  * This function, in the former case, or the hook, in the latter, is
186  * responsible for creating a set of vmcmds which can be used to build
187  * the process's vm space and inserting them into the exec package.
188  */
189 
190 int
191 exec_freebsd_aout_makecmds(p, epp)
192 	struct proc *p;
193 	struct exec_package *epp;
194 {
195 	u_long midmag;
196 	int error = ENOEXEC;
197 	struct exec *execp = epp->ep_hdr;
198 
199 	if (epp->ep_hdrvalid < sizeof(struct exec))
200 		return ENOEXEC;
201 
202 	midmag = FREEBSD_N_GETMID(*execp) << 16 | FREEBSD_N_GETMAGIC(*execp);
203 
204 	/* assume FreeBSD's MID_MACHINE and [ZQNO]MAGIC is same as NetBSD's */
205 	switch (midmag) {
206 	case (MID_MACHINE << 16) | ZMAGIC:
207 		error = exec_aout_prep_oldzmagic(p, epp);
208 		break;
209 	case (MID_MACHINE << 16) | QMAGIC:
210 		error = exec_aout_prep_zmagic(p, epp);
211 		break;
212 	case (MID_MACHINE << 16) | NMAGIC:
213 		error = exec_aout_prep_nmagic(p, epp);
214 		break;
215 	case (MID_MACHINE << 16) | OMAGIC:
216 		error = exec_aout_prep_omagic(p, epp);
217 		break;
218 	}
219 	if (error == 0)
220 		epp->ep_emul = &emul_freebsd_aout;
221 	else
222 		kill_vmcmds(&epp->ep_vmcmds);
223 
224 	return error;
225 }
226 #endif /* EXEC_AOUT */
227