1/* $NetBSD: nlist_coff.c,v 1.7 2009/02/16 10:40:45 lukem 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_coff.c,v 1.7 2009/02/16 10:40:45 lukem 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_COFF
57#include <sys/exec_coff.h>
58#endif
59
60#ifdef NLIST_COFF
61#define	BAD		do { rv = -1; goto out; } while (/*CONSTCOND*/0)
62#define	BADUNMAP	do { rv = -1; goto unmap; } while (/*CONSTCOND*/0)
63
64#define ES_LEN 18
65struct coff_extsym {
66	union {
67		char u_name[8];
68		struct {
69			int u_zero;
70			int u_offset;
71		} s;
72	} u;
73	int32_t es_value;
74	int16_t es_scnum;
75	int16_t es_type;
76	int8_t es_class;
77	int8_t es_numaux;
78};
79#define es_name u.u_name
80#define es_zero u.s.u_zero
81#define es_offset u.s.u_offset
82
83int
84__fdnlist_coff(fd, list)
85	int fd;
86	struct nlist *list;
87{
88	struct nlist *p;
89	struct coff_filehdr *filehdrp;
90	struct stat st;
91	char *mappedfile;
92	size_t mappedsize;
93	u_long symoff, extstroff;
94	int rv, nent;
95	long i, nesyms;
96
97	_DIAGASSERT(fd != -1);
98	_DIAGASSERT(list != NULL);
99
100	rv = -1;
101
102	/*
103	 * If we can't fstat() the file, something bad is going on.
104	 */
105	if (fstat(fd, &st) < 0)
106		BAD;
107
108	/*
109	 * Map the file in its entirety.
110	 */
111	if ((uintmax_t)st.st_size > (uintmax_t)SIZE_T_MAX) {
112		errno = EFBIG;
113		BAD;
114	}
115	mappedsize = st.st_size;
116	mappedfile = mmap(NULL, mappedsize, PROT_READ, MAP_PRIVATE|MAP_FILE,
117	    fd, 0);
118	if (mappedfile == (char *)-1)
119		BAD;
120
121	/*
122	 * Make sure we can access the executable's header
123	 * directly, and make sure we recognize the executable
124	 * as an COFF binary.
125	 */
126	if (mappedsize < sizeof (struct coff_filehdr))
127		BADUNMAP;
128	filehdrp = (struct coff_filehdr *)&mappedfile[0];
129
130	if (COFF_BADMAG(filehdrp))
131		BADUNMAP;
132
133	/*
134	 * Find the symbol list.
135	 */
136	symoff = filehdrp->f_symptr;
137	nesyms = filehdrp->f_nsyms;
138
139	if (symoff + ES_LEN * nesyms > mappedsize)
140		BADUNMAP;
141	extstroff = symoff + ES_LEN * nesyms;
142
143	nent = 0;
144	for (p = list; !ISLAST(p); ++p) {
145		p->n_type = 0;
146		p->n_other = 0;
147		p->n_desc = 0;
148		p->n_value = 0;
149		++nent;
150	}
151
152	for (i = 0; i < nesyms; i++) {
153		char *symtabname;
154		const char *nlistname;
155		struct coff_extsym esym;
156		char name[10];
157
158		memcpy(&esym, &mappedfile[symoff + ES_LEN * i], ES_LEN);
159		if (esym.es_numaux != 0) {
160			i += esym.es_numaux;	/* XXX Skip aux entry */
161			continue;
162		}
163
164		if (esym.es_zero != 0) {
165			memcpy(name, esym.es_name, 8);
166			name[8] = 0;
167			symtabname = name;
168		} else if (esym.es_offset != 0)
169			symtabname = &mappedfile[extstroff + esym.es_offset];
170		else
171			continue;
172
173		for (p = list; !ISLAST(p); p++) {
174			nlistname = N_NAME(p);
175			if (!strcmp(symtabname, nlistname)) {
176				/*
177				 * Translate (roughly) from COFF to nlist
178				 */
179				p->n_value = esym.es_value;
180				p->n_type = N_EXT;		/* XXX */
181				p->n_desc = 0;			/* XXX */
182				p->n_other = 0;			/* XXX */
183
184				if (--nent <= 0)
185					goto done;
186				break;	/* into next run of outer loop */
187			}
188		}
189	}
190
191done:
192	rv = nent;
193unmap:
194	munmap(mappedfile, mappedsize);
195out:
196	return (rv);
197}
198
199#endif /* NLIST_COFF */
200