xref: /netbsd-src/sys/compat/linux32/common/linux32_exec_elf32.c (revision 267197ec1eebfcb9810ea27a89625b6ddf68e3e7)
1 /*	$NetBSD: linux32_exec_elf32.c,v 1.7 2007/04/22 08:29:57 dsl Exp $ */
2 
3 /*-
4  * Copyright (c) 1995, 1998, 2000, 2001,2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas, Frank van der Linden, Eric Haszlakiewicz and
9  * Emmanuel Dreyfus.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *      This product includes software developed by the NetBSD
22  *      Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: linux32_exec_elf32.c,v 1.7 2007/04/22 08:29:57 dsl Exp $");
42 
43 #define	ELFSIZE		32
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/proc.h>
48 #include <sys/malloc.h>
49 #include <sys/vnode.h>
50 #include <sys/exec.h>
51 #include <sys/exec_elf.h>
52 #include <sys/kauth.h>
53 #include <sys/kernel.h>
54 #include <sys/resourcevar.h>
55 #include <sys/signal.h>
56 #include <sys/signalvar.h>
57 
58 #include <compat/linux/common/linux_exec.h>
59 #include <compat/netbsd32/netbsd32.h>
60 #include <compat/netbsd32/netbsd32_exec.h>
61 #include <compat/linux32/common/linux32_exec.h>
62 
63 #include <machine/frame.h>
64 
65 #ifdef DEBUG_LINUX
66 #define DPRINTF(a)      uprintf a
67 #else
68 #define DPRINTF(a)
69 #endif
70 
71 int linux32_copyinargs(struct exec_package *, struct ps_strings *,
72 			void *, size_t, const void *, const void *);
73 
74 int
75 ELFNAME2(linux32,probe)(l, epp, eh, itp, pos)
76 	struct lwp *l;
77 	struct exec_package *epp;
78 	void *eh;
79 	char *itp;
80 	vaddr_t *pos;
81 {
82 	int error;
83 
84 	if (((error = ELFNAME2(linux,signature)(l, epp, eh, itp)) != 0) &&
85 #ifdef LINUX32_GCC_SIGNATURE
86 	    ((error = ELFNAME2(linux,gcc_signature)(l, epp, eh)) != 0) &&
87 #endif
88 #ifdef LINUX32_ATEXIT_SIGNATURE
89 	    ((error = ELFNAME2(linux,atexit_signature)(l, epp, eh)) != 0) &&
90 #endif
91 #ifdef LINUX32_DEBUGLINK_SIGNATURE
92 	    ((error = ELFNAME2(linux,debuglink_signature)(l, epp, eh)) != 0) &&
93 #endif
94 	    1)
95 			return error;
96 
97 	if (itp) {
98 		if ((error = emul_find_interp(l, epp, itp)))
99 			return (error);
100 	}
101 #if 0
102 	DPRINTF(("linux32_probe: returning 0\n"));
103 #endif
104 
105 	epp->ep_flags |= EXEC_32;
106 	epp->ep_vm_minaddr = VM_MIN_ADDRESS;
107 	epp->ep_vm_maxaddr = USRSTACK32;
108 
109 	return 0;
110 }
111 
112 /* round up and down to page boundaries. */
113 #define	ELF_ROUND(a, b)		(((a) + (b) - 1) & ~((b) - 1))
114 #define	ELF_TRUNC(a, b)		((a) & ~((b) - 1))
115 
116 /*
117  * Copy arguments onto the stack in the normal way, but add some
118  * extra information in case of dynamic binding.
119  */
120 int
121 linux32_elf32_copyargs(struct lwp *l, struct exec_package *pack,
122     struct ps_strings *arginfo, char **stackp, void *argp)
123 {
124 	struct linux32_extra_stack_data *esdp, esd;
125 	struct elf_args *ap;
126 	struct vattr *vap;
127 	Elf_Ehdr *eh;
128 	Elf_Phdr *ph;
129 	Elf_Addr phdr = 0;
130 	u_long phsize;
131 	int error;
132 	int i;
133 
134 	if ((error = netbsd32_copyargs(l, pack, arginfo, stackp, argp)) != 0)
135 		return error;
136 
137 	/*
138 	 * Push extra arguments on the stack needed by dynamically
139 	 * linked binaries and static binaries as well.
140 	 */
141 	memset(&esd, 0, sizeof(esd));
142 	esdp = (struct linux32_extra_stack_data *)(*stackp);
143 	ap = (struct elf_args *)pack->ep_emul_arg;
144 	vap = pack->ep_vap;
145 	eh = (Elf_Ehdr *)pack->ep_hdr;
146 
147 	/*
148 	 * We forgot this, so we ned to reload it now. XXX keep track of it?
149 	 */
150 	if (ap == NULL) {
151 		phsize = eh->e_phnum * sizeof(Elf_Phdr);
152 		ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
153 		error = exec_read_from(l, pack->ep_vp, eh->e_phoff, ph, phsize);
154 		if (error != 0) {
155 			for (i = 0; i < eh->e_phnum; i++) {
156 				if (ph[i].p_type == PT_PHDR) {
157 					phdr = ph[i].p_vaddr;
158 					break;
159 				}
160 			}
161 		}
162 		free(ph, M_TEMP);
163 	}
164 
165 
166 	/*
167 	 * The exec_package doesn't have a proc pointer and it's not
168 	 * exactly trivial to add one since the credentials are
169 	 * changing. XXX Linux uses curlwp's credentials.
170 	 * Why can't we use them too? XXXad we do now; what's different
171 	 * about Linux's LWP creds?
172 	 */
173 
174 	i = 0;
175 	esd.ai[i].a_type = LINUX_AT_SYSINFO;
176 	esd.ai[i++].a_v = NETBSD32PTR32I(&esdp->kernel_vsyscall[0]);
177 
178 	esd.ai[i].a_type = LINUX_AT_SYSINFO_EHDR;
179 	esd.ai[i++].a_v = NETBSD32PTR32I(&esdp->elfhdr);
180 
181 	esd.ai[i].a_type = LINUX_AT_HWCAP;
182 	esd.ai[i++].a_v = LINUX32_CPUCAP;
183 
184 	esd.ai[i].a_type = AT_PAGESZ;
185 	esd.ai[i++].a_v = PAGE_SIZE;
186 
187 	esd.ai[i].a_type = LINUX_AT_CLKTCK;
188 	esd.ai[i++].a_v = hz;
189 
190 	esd.ai[i].a_type = AT_PHDR;
191 	esd.ai[i++].a_v = (ap ? ap->arg_phaddr: phdr);
192 
193 	esd.ai[i].a_type = AT_PHENT;
194 	esd.ai[i++].a_v = (ap ? ap->arg_phentsize : eh->e_phentsize);
195 
196 	esd.ai[i].a_type = AT_PHNUM;
197 	esd.ai[i++].a_v = (ap ? ap->arg_phnum : eh->e_phnum);
198 
199 	esd.ai[i].a_type = AT_BASE;
200 	esd.ai[i++].a_v = (ap ? ap->arg_interp : 0);
201 
202 	esd.ai[i].a_type = AT_FLAGS;
203 	esd.ai[i++].a_v = 0;
204 
205 	esd.ai[i].a_type = AT_ENTRY;
206 	esd.ai[i++].a_v = (ap ? ap->arg_entry : eh->e_entry);
207 
208 	esd.ai[i].a_type = LINUX_AT_EGID;
209 	esd.ai[i++].a_v = ((vap->va_mode & S_ISGID) ?
210 	    vap->va_gid : kauth_cred_getegid(l->l_cred));
211 
212 	esd.ai[i].a_type = LINUX_AT_GID;
213 	esd.ai[i++].a_v = kauth_cred_getgid(l->l_cred);
214 
215 	esd.ai[i].a_type = LINUX_AT_EUID;
216 	esd.ai[i++].a_v = ((vap->va_mode & S_ISUID) ?
217 	    vap->va_uid : kauth_cred_geteuid(l->l_cred));
218 
219 	esd.ai[i].a_type = LINUX_AT_UID;
220 	esd.ai[i++].a_v = kauth_cred_getuid(l->l_cred);
221 
222 	esd.ai[i].a_type = LINUX_AT_SECURE;
223 	esd.ai[i++].a_v = 0;
224 
225 	esd.ai[i].a_type = LINUX_AT_PLATFORM;
226 	esd.ai[i++].a_v = NETBSD32PTR32I(&esdp->hw_platform[0]);
227 
228 	esd.ai[i].a_type = AT_NULL;
229 	esd.ai[i++].a_v = 0;
230 
231 #ifdef DEBUG_LINUX
232 	if (i != LINUX32_ELF_AUX_ENTRIES) {
233 		printf("linux32_elf32_copyargs: %d Aux entries\n", i);
234 		return EINVAL;
235 	}
236 #endif
237 
238 	memcpy(esd.kernel_vsyscall, linux32_kernel_vsyscall,
239 	    sizeof(linux32_kernel_vsyscall));
240 
241 	memcpy(&esd.elfhdr, eh, sizeof(*eh));
242 
243 	strcpy(esd.hw_platform, LINUX32_PLATFORM);
244 
245 	if (ap) {
246 		free((char *)ap, M_TEMP);
247 		pack->ep_emul_arg = NULL;
248 	}
249 
250 	/*
251 	 * Copy out the ELF auxiliary table and hw platform name
252 	 */
253 	if ((error = copyout(&esd, esdp, sizeof(esd))) != 0)
254 		return error;
255 	*stackp += sizeof(esd);
256 	return 0;
257 }
258 
259