lib/libc/gen/nlist_ecoff.c

   1 /* $NetBSD: nlist_ecoff.c,v 1.23 2012/03/20 00:31:24 matt Exp $ */
   2
   3 /*
   4  * Copyright (c) 1996 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 for the
  18  *          NetBSD Project.  See http://www.NetBSD.org/ for
  19  *          information about NetBSD.
  20  * 4. The name of the author may not be used to endorse or promote products
  21  *    derived from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
  35  */
  36
  37 #include <sys/cdefs.h>
  38 #if defined(LIBC_SCCS) && !defined(lint)
  39 __RCSID("$NetBSD: nlist_ecoff.c,v 1.23 2012/03/20 00:31:24 matt Exp $");
  40 #endif /* LIBC_SCCS and not lint */
  41
  42 #include "namespace.h"
  43 #include <sys/param.h>
  44 #include <sys/mman.h>
  45 #include <sys/stat.h>
  46 #include <sys/file.h>
  47
  48 #include <assert.h>
  49 #include <errno.h>
  50 #include <stdio.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53 #include <nlist.h>
  54
  55 #include "nlist_private.h"
  56 #ifdef NLIST_ECOFF
  57 #include <sys/exec_ecoff.h>
  58 #endif
  59
  60 #ifdef NLIST_ECOFF
  61 #define check(off, size) \
  62         ((size_t)off >= mappedsize || (size_t)(off + size) > mappedsize)
  63
  64 int
  65 __fdnlist_ecoff(int fd, struct nlist *list)
  66 {
  67         struct nlist *p;
  68         const struct ecoff_exechdr *exechdrp;
  69         const struct ecoff_symhdr *symhdrp;
  70         const struct ecoff_extsym *esyms;
  71         struct stat st;
  72         const char *mappedfile;
  73         size_t mappedsize;
  74         u_long symhdroff, extstroff;
  75         u_int symhdrsize;
  76         int rv, nent;
  77         long i, nesyms;
  78
  79         _DIAGASSERT(fd != -1);
  80         _DIAGASSERT(list != NULL);
  81
  82         rv = -1;
  83
  84         /*
  85          * If we can't fstat() the file, something bad is going on.
  86          */
  87         if (fstat(fd, &st) < 0)
  88                 goto out;
  89
  90         /*
  91          * Map the file in its entirety.
  92          */
  93         if ((uintmax_t)st.st_size > (uintmax_t)SIZE_T_MAX) {
  94                 errno = EFBIG;
  95                 goto out;
  96         }
  97         mappedsize = (size_t)st.st_size;
  98         mappedfile = mmap(NULL, mappedsize, PROT_READ, MAP_PRIVATE|MAP_FILE,
  99             fd, 0);
 100         if (mappedfile == MAP_FAILED)
 101                 goto out;
 102
 103         /*
 104          * Make sure we can access the executable's header
 105          * directly, and make sure the recognize the executable
 106          * as an ECOFF binary.
 107          */
 108         if (check(0, sizeof *exechdrp))
 109                 goto unmap;
 110         exechdrp = (const void *)mappedfile;
 111
 112         if (ECOFF_BADMAG(exechdrp))
 113                 goto unmap;
 114
 115         /*
 116          * Find the symbol list.
 117          */
 118         symhdroff = exechdrp->f.f_symptr;
 119         symhdrsize = exechdrp->f.f_nsyms;
 120
 121         if ((symhdroff + sizeof *symhdrp) > mappedsize ||
 122             sizeof *symhdrp != symhdrsize)
 123                 goto unmap;
 124         symhdrp = (const void *)&mappedfile[symhdroff];
 125
 126         nesyms = symhdrp->esymMax;
 127         if (check(symhdrp->cbExtOffset, nesyms * sizeof *esyms))
 128                 goto unmap;
 129         esyms = (const void *)&mappedfile[symhdrp->cbExtOffset];
 130         extstroff = symhdrp->cbSsExtOffset;
 131
 132         /*
 133          * Clean out any left-over information for all valid entries.
 134          * Type and value are defined to be 0 if not found; historical
 135          * versions cleared other and desc as well.
 136          *
 137          * XXX Clearing anything other than n_type and n_value violates
 138          * the semantics given in the man page.
 139          */
 140         nent = 0;
 141         for (p = list; !ISLAST(p); ++p) {
 142                 p->n_type = 0;
 143                 p->n_other = 0;
 144                 p->n_desc = 0;
 145                 p->n_value = 0;
 146                 ++nent;
 147         }
 148
 149         for (i = 0; i < nesyms; i++) {
 150                 for (p = list; !ISLAST(p); p++) {
 151                         const char *nlistname;
 152                         const char *symtabname;
 153
 154                         /* This may be incorrect */
 155                         nlistname = N_NAME(p);
 156                         if (*nlistname == '_')
 157                                 nlistname++;
 158
 159                         symtabname =
 160                             &mappedfile[extstroff + esyms[i].es_strindex];
 161
 162                         if (!strcmp(symtabname, nlistname)) {
 163                                 /*
 164                                  * Translate (roughly) from ECOFF to nlist
 165                                  */
 166                                 p->n_value = esyms[i].es_value;
 167                                 p->n_type = N_EXT;              /* XXX */
 168                                 p->n_desc = 0;                  /* XXX */
 169                                 p->n_other = 0;                 /* XXX */
 170
 171                                 if (--nent <= 0)
 172                                         goto done;
 173                                 break;  /* into next run of outer loop */
 174                         }
 175                 }
 176         }
 177
 178 done:
 179         rv = nent;
 180 unmap:
 181         munmap(__UNCONST(mappedfile), mappedsize);
 182 out:
 183         return rv;
 184 }
 185
 186 #endif /* NLIST_ECOFF */