1 /* $NetBSD: vax1k_exec.c,v 1.19 2019/11/20 19:37:53 pgoyette 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 /* 34 * Exec glue to provide compatibility with older NetBSD vax1k exectuables. 35 * 36 * Because NetBSD/vax now uses 4k page size, older binaries (that started 37 * on an 1k boundary) cannot be mmap'ed. Therefore they are read in 38 * (via vn_rdwr) as OMAGIC binaries and executed. This will use a little 39 * bit more memory, but otherwise won't affect the execution speed. 40 */ 41 42 #include <sys/cdefs.h> 43 __KERNEL_RCSID(0, "$NetBSD: vax1k_exec.c,v 1.19 2019/11/20 19:37:53 pgoyette Exp $"); 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/resourcevar.h> 52 #include <sys/module.h> 53 54 #include <compat/vax1k/vax1k_exec.h> 55 56 #if defined(_KERNEL_OPT) 57 #include "opt_compat_43.h" 58 #else 59 #define COMPAT_43 /* enable 4.3BSD binaries for lkm */ 60 #endif 61 62 MODULE(MODULE_CLASS_EXEC, exec_vax1k, NULL); 63 64 int exec_vax1k_prep_anymagic(struct lwp *, struct exec_package *, 65 size_t, bool); 66 67 static struct execsw exec_vax1k_execsw = { 68 /* NetBSD vax1k a.out */ 69 .es_hdrsz = sizeof(struct exec), 70 .es_makecmds = exec_vax1k_makecmds, 71 .u = { 72 .elf_probe_func = NULL, 73 }, 74 .es_emul = &emul_netbsd, 75 .es_prio = EXECSW_PRIO_ANY, 76 .es_arglen = 0, 77 .es_copyargs = copyargs, 78 .es_setregs = NULL, 79 .es_coredump = coredump_netbsd, 80 .es_setup_stack = exec_setup_stack, 81 }; 82 83 static int 84 exec_vax1k_modcmd(modcmd_t cmd, void *arg) 85 { 86 87 switch (cmd) { 88 case MODULE_CMD_INIT: 89 return exec_add(&exec_vax1k_execsw, 1); 90 91 case MODULE_CMD_FINI: 92 return exec_remove(&exec_vax1k_execsw, 1); 93 94 default: 95 return ENOTTY; 96 } 97 } 98 99 /* 100 * exec_vax1k_makecmds(): Check if it's an a.out-format executable 101 * with an vax1k magic number. 102 * 103 * Given a proc pointer and an exec package pointer, see if the referent 104 * of the epp is in a.out format. Just check 'standard' magic numbers for 105 * this architecture. 106 * 107 * This function, in the former case, or the hook, in the latter, is 108 * responsible for creating a set of vmcmds which can be used to build 109 * the process's vm space and inserting them into the exec package. 110 */ 111 112 int 113 exec_vax1k_makecmds(struct lwp *l, struct exec_package *epp) 114 { 115 u_long midmag, magic; 116 u_short mid; 117 int error; 118 struct exec *execp = epp->ep_hdr; 119 120 if (epp->ep_hdrvalid < sizeof(struct exec)) 121 return ENOEXEC; 122 123 midmag = ntohl(execp->a_midmag); 124 mid = (midmag >> 16) & 0x3ff; 125 magic = midmag & 0xffff; 126 127 midmag = mid << 16 | magic; 128 129 switch (midmag) { 130 case (MID_VAX1K << 16) | ZMAGIC: 131 error = exec_vax1k_prep_anymagic(l, epp, 0, false); 132 goto done; 133 134 case (MID_VAX1K << 16) | NMAGIC: 135 error = exec_vax1k_prep_anymagic(l, epp, 136 sizeof(struct exec), true); 137 goto done; 138 139 case (MID_VAX1K << 16) | OMAGIC: 140 error = exec_vax1k_prep_anymagic(l, epp, 141 sizeof(struct exec), false); 142 goto done; 143 } 144 145 #ifdef COMPAT_43 146 /* 147 * 4.3BSD pre-dates CPU midmag (e.g. MID_VAX1K). instead, we 148 * expect a magic number in native byte order. 149 */ 150 switch (execp->a_midmag) { 151 case ZMAGIC: 152 error = exec_vax1k_prep_anymagic(l, epp, VAX1K_LDPGSZ, false); 153 goto done; 154 155 case NMAGIC: 156 error = exec_vax1k_prep_anymagic(l, epp, 157 sizeof(struct exec), true); 158 goto done; 159 160 case OMAGIC: 161 error = exec_vax1k_prep_anymagic(l, epp, 162 sizeof(struct exec), false); 163 goto done; 164 } 165 #endif 166 167 /* failed... */ 168 error = ENOEXEC; 169 170 done: 171 if (error) 172 kill_vmcmds(&epp->ep_vmcmds); 173 174 return error; 175 } 176 177 /* 178 * exec_vax1k_prep_anymagic(): Prepare an vax1k ?MAGIC binary's exec package 179 * 180 * First, set of the various offsets/lengths in the exec package. 181 * Note that all code is mapped RW; no protection, but because it is 182 * only used for compatibility it won't hurt. 183 * 184 */ 185 int 186 exec_vax1k_prep_anymagic(struct lwp *l, struct exec_package *epp, 187 size_t text_foffset, bool textpad) 188 { 189 struct exec *execp = epp->ep_hdr; 190 191 epp->ep_taddr = execp->a_entry & ~(VAX1K_USRTEXT - 1); 192 epp->ep_tsize = execp->a_text; 193 epp->ep_daddr = epp->ep_taddr + epp->ep_tsize; 194 if (textpad) /* pad for NMAGIC? */ 195 epp->ep_daddr = (epp->ep_daddr + (VAX1K_LDPGSZ - 1)) & 196 ~(VAX1K_LDPGSZ - 1); 197 epp->ep_dsize = execp->a_data; 198 epp->ep_entry = execp->a_entry; 199 200 /* first allocate memory for text+data+bss */ 201 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, 202 round_page(epp->ep_daddr + epp->ep_dsize + execp->a_bss) - 203 trunc_page(epp->ep_taddr), /* size */ 204 trunc_page(epp->ep_taddr), NULLVP, /* addr, vnode */ 205 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 206 207 /* then read the text in the area we just allocated */ 208 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_readvn, 209 epp->ep_tsize, epp->ep_taddr, epp->ep_vp, text_foffset, 210 VM_PROT_WRITE|VM_PROT_READ|VM_PROT_EXECUTE); 211 212 /* next read the data */ 213 if (epp->ep_dsize) { 214 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_readvn, 215 epp->ep_dsize, epp->ep_daddr, epp->ep_vp, 216 text_foffset + epp->ep_tsize, 217 VM_PROT_WRITE|VM_PROT_READ|VM_PROT_EXECUTE); 218 } 219 220 /* now bump up the dsize to include the bss so that sbrk works */ 221 epp->ep_dsize += execp->a_bss; 222 223 /* finally, setup the stack ... */ 224 return (*epp->ep_esch->es_setup_stack)(l, epp); 225 } 226