This is the new crunch utility for making distribution floppies from

James da Silva.  We need to integrate this before 1.1.5 so that we can
actually make the boot floppies.

3 files changed, 393 insertions, 0 deletions

diff --git a/usr.sbin/crunch/crunchide/Makefile b/usr.sbin/crunch/crunchide/Makefile
new file mode 100644
index 0000000..f6e1a8a
--- /dev/null
+++ b/usr.sbin/crunch/crunchide/Makefile
@@ -0,0 +1,4 @@
+
+PROG=   crunchide
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/crunch/crunchide/crunchide.1 b/usr.sbin/crunch/crunchide/crunchide.1
new file mode 100644
index 0000000..38a04cf
--- /dev/null
+++ b/usr.sbin/crunch/crunchide/crunchide.1
@@ -0,0 +1,68 @@
+.\"
+.\" 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
+.\"
+.Dd June 14, 1994
+.Dt CRUNCHIDE 1
+.Os BSD 4
+.Sh NAME
+.Nm crunchide
+.Nd hides symbol names from ld, for crunching programs together
+.Sh SYNOPSIS
+.Nm crunchide
+.Op Fl f Ar keep-list-file
+.Op Fl k Ar keep-symbol
+.Op Ar object-file ...
+.Sh DESCRIPTION
+
+.Nm Crunchide
+hides the global symbols of
+.Ar object-file
+such that they are ignored by subsequent runs of the linker, 
+.Xr ld 1 .
+Some symbols may be left visible via the
+.Fl k Ar keep-symbol
+and 
+.Fl f Ar keep-list-file
+options.  The
+.Ar keep-list-file
+must contain a list of symbols to keep visible, one symbol per line.
+Note that the C compiler prepends an underscore in front of
+symbols, so to keep the C function ``foo'' visible, the option
+\&``-k _foo'' must be used.
+
+.Pp
+.Nm Crunchide
+is designed as a companion program for 
+.Xr crunchgen 1 ,
+which automates the process of creating crunched binaries from
+multiple component programs.
+.Sh SEE ALSO
+.Xr crunchgen 1 ,
+.Xr ld 1
+.Sh AUTHOR
+.Nm Crunch
+was written by James da Silva <jds@cs.umd.edu>.
+.sp 0
+Copyright (c) 1994 University of Maryland.  All Rights Reserved.
diff --git a/usr.sbin/crunch/crunchide/crunchide.c b/usr.sbin/crunch/crunchide/crunchide.c
new file mode 100644
index 0000000..ae54da0
--- /dev/null
+++ b/usr.sbin/crunch/crunchide/crunchide.c
@@ -0,0 +1,321 @@
+/*
+ * 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:
+ *	- resolve the theoretical hanging reloc problem (see check_reloc()
+ *	  below). I have yet to see this problem actually occur in any real
+ *	  program. In what cases will gcc/gas generate code that needs a
+ *	  relative reloc from a global symbol, other than PIC?  The
+ *	  solution is to not hide the symbol from the linker in this case,
+ *	  but to generate some random name for it so that it doesn't link
+ *	  with anything but holds the place for the reloc.
+ *      - 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 <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <a.out.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/errno.h>
+
+char *pname = "crunchide";
+
+void usage(void);
+
+void add_to_keep_list(char *symbol);
+void add_file_to_keep_list(char *filename);
+
+void hide_syms(char *filename);
+
+
+int main(argc, argv)
+int argc;
+char **argv;
+{
+    int ch;
+
+    if(argc > 0) pname = argv[0];
+
+    while ((ch = getopt(argc, argv, "k:f:")) != EOF)
+	switch(ch) {
+	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();
+
+    while(argc) {
+	hide_syms(*argv);
+	argc--, argv++;
+    }
+
+    return 0;
+}
+
+void usage(void)
+{
+    fprintf(stderr,
+	    "Usage: %s [-k <symbol-name>] [-f <keep-list-file>] <files> ...\n",
+	    pname);
+    exit(1);
+}
+
+/* ---------------------------- */
+
+struct keep {
+    struct keep *next;
+    char *sym;
+} *keep_list;
+
+void add_to_keep_list(char *symbol)
+{
+    struct keep *newp, *prevp, *curp;
+    int cmp;
+
+    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 = (struct keep *) malloc(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", pname);
+	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;
+
+    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, 1024, keepf)) {
+	len = strlen(symbol);
+	if(len && symbol[len-1] == '\n')
+	    symbol[len-1] = '\0';
+
+	add_to_keep_list(symbol);
+    }
+    fclose(keepf);
+}
+
+/* ---------------------- */
+
+int nsyms, ntextrel, ndatarel;
+struct exec *hdrp;
+char *aoutdata, *strbase;
+struct relocation_info *textrel, *datarel;
+struct nlist *symbase;
+
+
+#define SYMSTR(sp)	&strbase[(sp)->n_un.n_strx]
+
+/* is the symbol a global symbol defined in the current file? */
+#define IS_GLOBAL_DEFINED(sp) \
+                  (((sp)->n_type & N_EXT) && ((sp)->n_type & N_TYPE) != N_UNDF)
+
+/* is the relocation entry dependent on a symbol? */
+#define IS_SYMBOL_RELOC(rp)   \
+                  ((rp)->r_extern||(rp)->r_baserel||(rp)->r_jmptable)
+
+void check_reloc(char *filename, struct relocation_info *relp);
+
+void hide_syms(char *filename)
+{
+    int inf, outf, rc;
+    struct stat infstat;
+    struct relocation_info *relp;
+    struct nlist *symp;
+
+    /*
+     * 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(struct exec)) {
+	fprintf(stderr, "%s: short file\n", filename);
+	close(inf);
+	return;
+    }
+
+    /*
+     * Read the entire file into memory.  XXX - Really, we only need to
+     * read the header and from TRELOFF to the end of the file.
+     */
+
+    if((aoutdata = (char *) malloc(infstat.st_size)) == NULL) {
+	fprintf(stderr, "%s: too big to read into memory\n", filename);
+	close(inf);
+	return;
+    }
+
+    if((rc = read(inf, aoutdata, infstat.st_size)) < infstat.st_size) {
+	fprintf(stderr, "%s: read error: %s\n", filename,
+		rc == -1? strerror(errno) : "short read");
+	close(inf);
+	return;
+    }
+
+    /*
+     * Check the header and calculate offsets and sizes from it.
+     */
+
+    hdrp = (struct exec *) aoutdata;
+
+    if(N_BADMAG(*hdrp)) {
+	fprintf(stderr, "%s: bad magic: not an a.out file\n", filename);
+	close(inf);
+	return;
+    }
+
+#ifdef __FreeBSD__
+    textrel = (struct relocation_info *) (aoutdata + N_RELOFF(*hdrp));
+    datarel = (struct relocation_info *) (aoutdata + N_RELOFF(*hdrp) +
+					  hdrp->a_trsize);
+#else
+    textrel = (struct relocation_info *) (aoutdata + N_TRELOFF(*hdrp));
+    datarel = (struct relocation_info *) (aoutdata + N_DRELOFF(*hdrp));
+#endif
+    symbase = (struct nlist *)		 (aoutdata + N_SYMOFF(*hdrp));
+    strbase = (char *) 			 (aoutdata + N_STROFF(*hdrp));
+
+    ntextrel = hdrp->a_trsize / sizeof(struct relocation_info);
+    ndatarel = hdrp->a_drsize / sizeof(struct relocation_info);
+    nsyms    = hdrp->a_syms   / sizeof(struct nlist);
+
+    /*
+     * Zap the type field of all globally-defined symbols.  The linker will
+     * subsequently ignore these entries.  Don't zap any symbols in the
+     * keep list.
+     */
+
+    for(symp = symbase; symp < symbase + nsyms; symp++)
+	if(IS_GLOBAL_DEFINED(symp) && !in_keep_list(SYMSTR(symp)))
+	    symp->n_type = 0;
+
+    /*
+     * Check whether the relocation entries reference any symbols that we
+     * just zapped.  I don't know whether ld can handle this case, but I
+     * haven't encountered it yet.  These checks are here so that the program
+     * doesn't fail silently should such symbols be encountered.
+     */
+
+    for(relp = textrel; relp < textrel + ntextrel; relp++)
+	check_reloc(filename, relp);
+    for(relp = datarel; relp < datarel + ndatarel; relp++)
+	check_reloc(filename, relp);
+
+    /*
+     * Write the .o file back out to disk.  XXX - Really, we only need to
+     * write the symbol table entries back out.
+     */
+    lseek(inf, 0, SEEK_SET);
+    if((rc = write(inf, aoutdata, infstat.st_size)) < infstat.st_size) {
+	fprintf(stderr, "%s: write error: %s\n", filename,
+		rc == -1? strerror(errno) : "short write");
+    }
+
+    close(inf);
+}
+
+
+void check_reloc(char *filename, struct relocation_info *relp)
+{
+    /* bail out if we zapped a symbol that is needed */
+    if(IS_SYMBOL_RELOC(relp) && symbase[relp->r_symbolnum].n_type == 0) {
+	fprintf(stderr,
+		"%s: oops, have hanging relocation for %s: bailing out!\n",
+		filename, SYMSTR(&symbase[relp->r_symbolnum]));
+	exit(1);
+    }
+}