xref: /netbsd-src/sys/compat/linux/arch/powerpc/linux_exec_powerpc.c (revision bfb6cb13d599546df69c7e4d20d70e22e15a549d)
1 /* $NetBSD: linux_exec_powerpc.c,v 1.20 2006/07/23 22:06:09 ad Exp $ */
2 
3 /*-
4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Emmanuel Dreyfus.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by the NetBSD
21  *      Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * From NetBSD's sys/compat/arch/alpha/linux_exec_alpha.c, with some
41  * powerpc add-ons (ifdef LINUX_SHIFT).
42  *
43  * This code is to be common to alpha and powerpc. If it works on alpha, it
44  * should be moved to common/linux_exec_elf32.c. Beware that it needs
45  * LINUX_ELF_AUX_ENTRIES in arch/<arch>/linux_exec.h to also be moved to common
46  *
47  * Emmanuel Dreyfus <p99dreyf@criens.u-psud.fr>
48  */
49 
50 #include <sys/cdefs.h>
51 __KERNEL_RCSID(0, "$NetBSD: linux_exec_powerpc.c,v 1.20 2006/07/23 22:06:09 ad Exp $");
52 
53 #if defined (__alpha__)
54 #define ELFSIZE 64
55 #elif defined (__powerpc__)
56 #define ELFSIZE 32
57 #else
58 #error Unified linux_elf_{32|64}copyargs not tested for this platform
59 #endif
60 
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/kernel.h>
64 #include <sys/malloc.h>
65 #include <sys/proc.h>
66 #include <sys/exec.h>
67 #include <sys/exec_elf.h>
68 #include <sys/resourcevar.h>
69 #include <sys/kauth.h>
70 
71 #include <uvm/uvm_extern.h>
72 
73 #include <compat/linux/common/linux_exec.h>
74 
75 /*
76  * Alpha and PowerPC specific linux copyargs function.
77  */
78 int
79 ELFNAME2(linux,copyargs)(l, pack, arginfo, stackp, argp)
80 	struct lwp *l;
81 	struct exec_package *pack;
82 	struct ps_strings *arginfo;
83 	char **stackp;
84 	void *argp;
85 {
86 	size_t len;
87 	AuxInfo ai[LINUX_ELF_AUX_ENTRIES], *a;
88 	struct elf_args *ap;
89 	int error;
90 
91 #ifdef LINUX_SHIFT
92 	/*
93 	 * Seems that PowerPC Linux binaries expect argc to start on a 16 bytes
94 	 * aligned address. And we need one more 16 byte shift if it was already
95 	 * 16 bytes aligned,
96 	 */
97 	*stackp = (char *)(((unsigned long)*stackp - 1) & ~LINUX_SHIFT);
98 #endif
99 
100 	if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0)
101 		return error;
102 
103 #ifdef LINUX_SHIFT
104 	/*
105 	 * From Linux's arch/ppc/kernel/process.c:shove_aux_table(). GNU ld.so
106 	 * expects the ELF auxiliary table to start on a 16 bytes boundary on
107 	 * the PowerPC.
108 	 */
109 	*stackp = (char *)(((unsigned long)(*stackp) + LINUX_SHIFT)
110 	    & ~LINUX_SHIFT);
111 #endif
112 
113 	memset(ai, 0, sizeof(AuxInfo) * LINUX_ELF_AUX_ENTRIES);
114 
115 	a = ai;
116 
117 	/*
118 	 * Push extra arguments on the stack needed by dynamically
119 	 * linked binaries.
120 	 */
121 	if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
122 #if 1
123 		/*
124 		 * The exec_package doesn't have a proc pointer and it's not
125 		 * exactly trivial to add one since the credentials are
126 		 * changing. XXX Linux uses curlwp's credentials.
127 		 * Why can't we use them too? XXXad we do, what's different?
128 		 */
129 		a->a_type = LINUX_AT_EGID;
130 		a->a_v = kauth_cred_getegid(l->l_cred);
131 		a++;
132 
133 		a->a_type = LINUX_AT_GID;
134 		a->a_v = kauth_cred_getgid(l->l_cred);
135 		a++;
136 
137 		a->a_type = LINUX_AT_EUID;
138 		a->a_v = kauth_cred_geteuid(l->l_cred);
139 		a++;
140 
141 		a->a_type = LINUX_AT_UID;
142 		a->a_v = kauth_cred_getuid(l->l_cred);
143 		a++;
144 #endif
145 
146 		a->a_type = AT_ENTRY;
147 		a->a_v = ap->arg_entry;
148 		a++;
149 
150 		a->a_type = AT_FLAGS;
151 		a->a_v = 0;
152 		a++;
153 
154 		a->a_type = AT_BASE;
155 		a->a_v = ap->arg_interp;
156 		a++;
157 
158 		a->a_type = AT_PHNUM;
159 		a->a_v = ap->arg_phnum;
160 		a++;
161 
162 		a->a_type = AT_PHENT;
163 		a->a_v = ap->arg_phentsize;
164 		a++;
165 
166 		a->a_type = AT_PHDR;
167 		a->a_v = ap->arg_phaddr;
168 		a++;
169 
170 		a->a_type = LINUX_AT_CLKTCK;
171 		a->a_v = LINUX_CLOCKS_PER_SEC;
172 		a++;
173 
174 		a->a_type = AT_PAGESZ;
175 		a->a_v = PAGE_SIZE;
176 		a++;
177 
178 		a->a_type = LINUX_AT_HWCAP;
179 		a->a_v = LINUX_ELF_HWCAP;
180 		a++;
181 
182 		free((char *)ap, M_TEMP);
183 		pack->ep_emul_arg = NULL;
184 	}
185 
186 	a->a_type = AT_NULL;
187 	a->a_v = 0;
188 	a++;
189 
190 	len = (a - ai) * sizeof(AuxInfo);
191 
192 	if ((error = copyout(ai, *stackp, len)) != 0)
193 		return error;
194 	*stackp += len;
195 	return 0;
196 }
197