1 /* $NetBSD: freebsd_exec_elf32.c,v 1.17 2007/04/22 08:29:56 dsl 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 <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: freebsd_exec_elf32.c,v 1.17 2007/04/22 08:29:56 dsl Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/proc.h> 39 #include <sys/malloc.h> 40 #include <sys/vnode.h> 41 #include <sys/exec.h> 42 #ifndef ELFSIZE 43 # define ELFSIZE 32 44 #endif /* !ELFSIZE */ 45 #include <sys/exec_elf.h> 46 47 #include <compat/sys/signal.h> 48 #include <compat/sys/signalvar.h> 49 50 #include <compat/freebsd/freebsd_exec.h> 51 #include <compat/common/compat_util.h> 52 53 #include <machine/freebsd_machdep.h> 54 55 56 int 57 ELFNAME2(freebsd,probe)( 58 struct lwp *l, 59 struct exec_package *epp, 60 void *veh, 61 char *itp, 62 vaddr_t *pos) 63 { 64 int error; 65 size_t i; 66 size_t phsize; 67 Elf_Ehdr *eh = (Elf_Ehdr *) veh; 68 Elf_Phdr *ph; 69 Elf_Phdr *ephp; 70 Elf_Nhdr *np; 71 72 static const char wantBrand[] = FREEBSD_ELF_BRAND_STRING; 73 static const char wantInterp[] = FREEBSD_ELF_INTERP_PREFIX_STRING; 74 75 /* 76 * Insist that the executable have a brand, and that it be "FreeBSD". 77 * Newer FreeBSD binaries have OSABI set to ELFOSABI_FREEBSD. This 78 * is arguably broken, but they seem to think they need it, for 79 * whatever reason. 80 */ 81 #ifndef EI_BRAND 82 #define EI_BRAND 8 83 #endif 84 if ((eh->e_ident[EI_BRAND] == '\0' 85 || strcmp(&eh->e_ident[EI_BRAND], wantBrand) != 0) 86 && eh->e_ident[EI_OSABI] != ELFOSABI_FREEBSD) 87 return ENOEXEC; 88 89 i = eh->e_phnum; 90 if (i != 0) { 91 phsize = i * sizeof(Elf_Phdr); 92 ph = (Elf_Phdr *) malloc(phsize, M_TEMP, M_WAITOK); 93 if ((error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, 94 phsize)) != 0) 95 goto bad1; 96 97 for (ephp = ph; i--; ephp++) { 98 if (ephp->p_type != PT_INTERP) 99 continue; 100 101 /* Check for "legal" intepreter name. */ 102 if (ephp->p_filesz < sizeof wantInterp) 103 goto bad1; 104 105 np = (Elf_Nhdr *) malloc(ephp->p_filesz+1, 106 M_TEMP, M_WAITOK); 107 108 if (((error = exec_read_from(l, epp->ep_vp, 109 ephp->p_offset, np, ephp->p_filesz)) != 0)) 110 goto bad2; 111 112 if (strncmp((char *)np, wantInterp, 113 sizeof wantInterp - 1)) 114 goto bad2; 115 116 free(np, M_TEMP); 117 break; 118 } 119 free(ph, M_TEMP); 120 } 121 122 if (itp) { 123 if ((error = emul_find_interp(l, epp, itp))) 124 return error; 125 } 126 #ifdef DEBUG_FREEBSD_ELF 127 printf("freebsd_elf32_probe: returning 0\n"); 128 #endif 129 return 0; 130 131 bad2: 132 free(np, M_TEMP); 133 bad1: 134 free(ph, M_TEMP); 135 return ENOEXEC; 136 } 137