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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/crunchgen/crunchide.c	Lines:	0	70	0.0 %
Date:	2017-11-13	Branches:	0	57	0.0 %


/* $OpenBSD: crunchide.c,v 1.12 2017/10/29 08:45:53 mpi Exp $	 */

/*
 * Copyright (c) 1994 University of Maryland
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of U.M. not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  U.M. makes no representations about the
 * suitability of this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 *
 * U.M. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL U.M.
 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Author: James da Silva, Systems Design and Analysis Group
 *			   Computer Science Department
 *			   University of Maryland at College Park
 */
/*
 * crunchide.c - tiptoes through an a.out symbol table, hiding all defined
 *	global symbols.  Allows the user to supply a "keep list" of symbols
 *	that are not to be hidden.  This program relies on the use of the
 * 	linker's -dc flag to actually put global bss data into the file's
 * 	bss segment (rather than leaving it as undefined "common" data).
 *
 * 	The point of all this is to allow multiple programs to be linked
 *	together without getting multiple-defined errors.
 *
 *	For example, consider a program "foo.c".  It can be linked with a
 *	small stub routine, called "foostub.c", eg:
 *	    int foo_main(int argc, char **argv){ return main(argc, argv); }
 *      like so:
 *	    cc -c foo.c foostub.c
 *	    ld -dc -r foo.o foostub.o -o foo.combined.o
 *	    crunchide -k _foo_main foo.combined.o
 *	at this point, foo.combined.o can be linked with another program
 * 	and invoked with "foo_main(argc, argv)".  foo's main() and any
 * 	other globals are hidden and will not conflict with other symbols.
 *
 * TODO:
 *      - arrange that all the BSS segments start at the same address, so
 *	  that the final crunched binary BSS size is the max of all the
 *	  component programs' BSS sizes, rather than their sum.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>

#include <elf.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "mangle.h"

void	usage(void);

void	add_to_keep_list(char *);
void	add_file_to_keep_list(char *);

void	hide_syms(char *);
void	elf_hide(int, char *);
int	in_keep_list(char *symbol);
int	crunchide_main(int argc, char *argv[]);

extern char	*__progname;
extern int elf_mangle;

int
crunchide_main(int argc, char *argv[])
{
	int             ch;

	while ((ch = getopt(argc, argv, "Mhk:f:")) != -1)
		switch (ch) {
		case 'M':
			elf_mangle = 1;
			break;
		case 'h':
			break;
		case 'k':
			add_to_keep_list(optarg);
			break;
		case 'f':
			add_file_to_keep_list(optarg);
			break;
		default:
			usage();
		}

	argc -= optind;
	argv += optind;

	if (argc == 0)
		usage();

	if (elf_mangle)
		init_mangle_state();

	while (argc) {
		hide_syms(*argv);
		argc--;
		argv++;
	}
	if (elf_mangle)
		fini_mangle_state();

	return 0;
}

struct keep {
	struct keep    *next;
	char           *sym;
} *keep_list;

void
add_to_keep_list(char *symbol)
{
	struct keep    *newp, *prevp, *curp;
	int             cmp = 0;

	for (curp = keep_list, prevp = NULL; curp; prevp = curp, curp = curp->next)
		if ((cmp = strcmp(symbol, curp->sym)) <= 0)
			break;

	if (curp && cmp == 0)
		return;		/* already in table */

	newp = calloc(1, sizeof(struct keep));
	if (newp)
		newp->sym = strdup(symbol);
	if (newp == NULL || newp->sym == NULL) {
		fprintf(stderr, "%s: out of memory for keep list\n", __progname);
		exit(1);
	}
	newp->next = curp;
	if (prevp)
		prevp->next = newp;
	else
		keep_list = newp;
}

int
in_keep_list(char *symbol)
{
	struct keep    *curp;
	int             cmp = 0;

	for (curp = keep_list; curp; curp = curp->next)
		if ((cmp = strcmp(symbol, curp->sym)) <= 0)
			break;

	return curp && cmp == 0;
}

void
add_file_to_keep_list(char *filename)
{
	FILE           *keepf;
	char            symbol[1024];
	int             len;

	if ((keepf = fopen(filename, "r")) == NULL) {
		perror(filename);
		usage();
	}
	while (fgets(symbol, sizeof(symbol), keepf)) {
		len = strlen(symbol);
		if (len && symbol[len - 1] == '\n')
			symbol[len - 1] = '\0';

		add_to_keep_list(symbol);
	}
	fclose(keepf);
}

void
hide_syms(char *filename)
{
	int             inf;
	struct stat     infstat;
	char           *buf;

	/*
         * Open the file and do some error checking.
         */

	if ((inf = open(filename, O_RDWR)) == -1) {
		perror(filename);
		return;
	}
	if (fstat(inf, &infstat) == -1) {
		perror(filename);
		close(inf);
		return;
	}
	if (infstat.st_size < sizeof(Elf_Ehdr) || infstat.st_size > SIZE_MAX) {
		fprintf(stderr, "%s: invalid file size\n", filename);
		close(inf);
		return;
	}
	if ((buf = mmap(NULL, infstat.st_size, PROT_READ | PROT_WRITE,
	    MAP_FILE | MAP_SHARED, inf, 0)) == MAP_FAILED) {
		fprintf(stderr, "%s: cannot map\n", filename);
		close(inf);
		return;
	}

	if (buf[0] == ELFMAG0 && buf[1] == ELFMAG1 &&
	    buf[2] == ELFMAG2 && buf[3] == ELFMAG3) {
		elf_hide(inf, buf);
		return;
	}

	close(inf);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: crunchide.c,v 1.12 2017/10/29 08:45:53 mpi Exp $ */
2
3			/*
4			* Copyright (c) 1994 University of Maryland
5			* All Rights Reserved.
6			*
7			* Permission to use, copy, modify, distribute, and sell this software and its
8			* documentation for any purpose is hereby granted without fee, provided that
9			* the above copyright notice appear in all copies and that both that
10			* copyright notice and this permission notice appear in supporting
11			* documentation, and that the name of U.M. not be used in advertising or
12			* publicity pertaining to distribution of the software without specific,
13			* written prior permission. U.M. makes no representations about the
14			* suitability of this software for any purpose. It is provided "as is"
15			* without express or implied warranty.
16			*
17			* U.M. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
18			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL U.M.
19			* BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
20			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
21			* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
22			* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23			*
24			* Author: James da Silva, Systems Design and Analysis Group
25			* Computer Science Department
26			* University of Maryland at College Park
27			*/
28			/*
29			* crunchide.c - tiptoes through an a.out symbol table, hiding all defined
30			* global symbols. Allows the user to supply a "keep list" of symbols
31			* that are not to be hidden. This program relies on the use of the
32			* linker's -dc flag to actually put global bss data into the file's
33			* bss segment (rather than leaving it as undefined "common" data).
34			*
35			* The point of all this is to allow multiple programs to be linked
36			* together without getting multiple-defined errors.
37			*
38			* For example, consider a program "foo.c". It can be linked with a
39			* small stub routine, called "foostub.c", eg:
40			* int foo_main(int argc, char **argv){ return main(argc, argv); }
41			* like so:
42			* cc -c foo.c foostub.c
43			* ld -dc -r foo.o foostub.o -o foo.combined.o
44			* crunchide -k _foo_main foo.combined.o
45			* at this point, foo.combined.o can be linked with another program
46			* and invoked with "foo_main(argc, argv)". foo's main() and any
47			* other globals are hidden and will not conflict with other symbols.
48			*
49			* TODO:
50			* - arrange that all the BSS segments start at the same address, so
51			* that the final crunched binary BSS size is the max of all the
52			* component programs' BSS sizes, rather than their sum.
53			*/
54
55			#include <sys/types.h>
56			#include <sys/mman.h>
57			#include <sys/stat.h>
58
59			#include <elf.h>
60			#include <fcntl.h>
61			#include <stdint.h>
62			#include <stdio.h>
63			#include <stdlib.h>
64			#include <string.h>
65			#include <unistd.h>
66
67			#include "mangle.h"
68
69			void usage(void);
70
71			void add_to_keep_list(char *);
72			void add_file_to_keep_list(char *);
73
74			void hide_syms(char *);
75			void elf_hide(int, char *);
76			int in_keep_list(char *symbol);
77			int crunchide_main(int argc, char *argv[]);
78
79			extern char *__progname;
80			extern int elf_mangle;
81
82			int
83			crunchide_main(int argc, char *argv[])
84			{
85			int ch;
86
87			while ((ch = getopt(argc, argv, "Mhk:f:")) != -1)
88			switch (ch) {
89			case 'M':
90			elf_mangle = 1;
91			break;
92			case 'h':
93			break;
94			case 'k':
95			add_to_keep_list(optarg);
96			break;
97			case 'f':
98			add_file_to_keep_list(optarg);
99			break;
100			default:
101			usage();
102			}
103
104			argc -= optind;
105			argv += optind;
106
107			if (argc == 0)
108			usage();
109
110			if (elf_mangle)
111			init_mangle_state();
112
113			while (argc) {
114			hide_syms(*argv);
115			argc--;
116			argv++;
117			}
118			if (elf_mangle)
119			fini_mangle_state();
120
121			return 0;
122			}
123
124			struct keep {
125			struct keep *next;
126			char *sym;
127			} *keep_list;
128
129			void
130			add_to_keep_list(char *symbol)
131			{
132			struct keep newp, prevp, *curp;
133			int cmp = 0;
134
135			for (curp = keep_list, prevp = NULL; curp; prevp = curp, curp = curp->next)
136			if ((cmp = strcmp(symbol, curp->sym)) <= 0)
137			break;
138
139			if (curp && cmp == 0)
140			return; /* already in table */
141
142			newp = calloc(1, sizeof(struct keep));
143			if (newp)
144			newp->sym = strdup(symbol);
145			if (newp == NULL \|\| newp->sym == NULL) {
146			fprintf(stderr, "%s: out of memory for keep list\n", __progname);
147			exit(1);
148			}
149			newp->next = curp;
150			if (prevp)
151			prevp->next = newp;
152			else
153			keep_list = newp;
154			}
155
156			int
157			in_keep_list(char *symbol)
158			{
159			struct keep *curp;
160			int cmp = 0;
161
162			for (curp = keep_list; curp; curp = curp->next)
163			if ((cmp = strcmp(symbol, curp->sym)) <= 0)
164			break;
165
166			return curp && cmp == 0;
167			}
168
169			void
170			add_file_to_keep_list(char *filename)
171			{
172			FILE *keepf;
173			char symbol[1024];
174			int len;
175
176			if ((keepf = fopen(filename, "r")) == NULL) {
177			perror(filename);
178			usage();
179			}
180			while (fgets(symbol, sizeof(symbol), keepf)) {
181			len = strlen(symbol);
182			if (len && symbol[len - 1] == '\n')
183			symbol[len - 1] = '\0';
184
185			add_to_keep_list(symbol);
186			}
187			fclose(keepf);
188			}
189
190			void
191			hide_syms(char *filename)
192			{
193			int inf;
194			struct stat infstat;
195			char *buf;
196
197			/*
198			* Open the file and do some error checking.
199			*/
200
201			if ((inf = open(filename, O_RDWR)) == -1) {
202			perror(filename);
203			return;
204			}
205			if (fstat(inf, &infstat) == -1) {
206			perror(filename);
207			close(inf);
208			return;
209			}
210			if (infstat.st_size < sizeof(Elf_Ehdr) \|\| infstat.st_size > SIZE_MAX) {
211			fprintf(stderr, "%s: invalid file size\n", filename);
212			close(inf);
213			return;
214			}
215			if ((buf = mmap(NULL, infstat.st_size, PROT_READ \| PROT_WRITE,
216			MAP_FILE \| MAP_SHARED, inf, 0)) == MAP_FAILED) {
217			fprintf(stderr, "%s: cannot map\n", filename);
218			close(inf);
219			return;
220			}
221
222			if (buf[0] == ELFMAG0 && buf[1] == ELFMAG1 &&
223			buf[2] == ELFMAG2 && buf[3] == ELFMAG3) {
224			elf_hide(inf, buf);
225			return;
226			}
227
228			close(inf);
229			}