Merge crunchgen & crunchhide (using name checking), and move to usr.sbin

next step is to not install it as two programs, but be even more clever

1 files changed, 474 insertions, 0 deletions

diff --git a/usr.sbin/crunchgen/elf_hide.c b/usr.sbin/crunchgen/elf_hide.c
new file mode 100644
index 00000000000..b52a7757b07
--- /dev/null
+++ b/usr.sbin/crunchgen/elf_hide.c
@@ -0,0 +1,474 @@
+/* $OpenBSD: elf_hide.c,v 1.1 2008/08/22 15:18:55 deraadt Exp $ */
+
+/*
+ * Copyright (c) 1997 Dale Rahn.
+ * All rights reserved.
+ *
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/exec.h>
+#ifdef _NLIST_DO_ELF
+#include <sys/exec_elf.h>
+
+void	load_strtab(Elf_Ehdr * pehdr, char *pexe);
+void	dump_strtab();
+char	*get_str(int indx);
+
+void	load_symtab(Elf_Ehdr * pehdr, char *pexe);
+void	dump_symtab();
+
+void	load_shstr_tab(Elf_Ehdr * pehdr, char *pexe);
+char	*get_shstr(int indx);
+void	fprint_shstr(FILE * channel, int indx);
+
+void	hide_sym();
+void	reorder_syms(Elf_Ehdr * ehdr, Elf_Shdr * symsect,
+	    Elf_Sym * symtab, int symtabsize, int symtabsecnum);
+typedef long    Symmap;
+void	renum_reloc_syms(Elf_Ehdr * ehdr, Symmap * symmap,
+	    int symtabsecnum);
+
+
+char           *pexe;
+
+void
+elf_hide(int pfile, char *p)
+{
+	Elf_Ehdr       *pehdr;
+#ifdef DEBUG
+	Elf_Shdr       *pshdr;
+	Elf_Phdr       *pphdr;
+	int             i;
+#endif
+	struct stat     sb;
+
+	pexe = p;
+	pehdr = (Elf_Ehdr *) pexe;
+
+#ifdef DEBUG
+	printf("elf header\n");
+	printf("e_type %x\n", pehdr->e_type);
+	printf("e_machine %x\n", pehdr->e_machine);
+	printf("e_version %x\n", pehdr->e_version);
+	printf("e_entry %x\n", pehdr->e_entry);
+	printf("e_phoff %x\n", pehdr->e_phoff);
+	printf("e_shoff %x\n", pehdr->e_shoff);
+	printf("e_flags %x\n", pehdr->e_flags);
+	printf("e_ehsize %x\n", pehdr->e_ehsize);
+	printf("e_phentsize %x\n", pehdr->e_phentsize);
+	printf("e_phnum %x\n", pehdr->e_phnum);
+	printf("e_shentsize %x\n", pehdr->e_shentsize);
+	printf("e_shnum %x\n", pehdr->e_shnum);
+	printf("e_shstrndx %x\n", pehdr->e_shstrndx);
+#endif
+
+	load_shstr_tab(pehdr, pexe);
+#ifdef DEBUG
+	for (i = 0; i < pehdr->e_shnum; i++) {
+		pshdr = (Elf_Phdr *) (pexe + pehdr->e_shoff +
+		    (i * pehdr->e_shentsize));
+
+		printf("section header %d\n", i);
+		printf("sh_name %x ", pshdr->sh_name);
+		fprint_shstr(stdout, pshdr->sh_name);
+		printf("\n");
+		printf("sh_type %x\n", pshdr->sh_type);
+		printf("sh_flags %x\n", pshdr->sh_flags);
+		printf("sh_addr %x\n", pshdr->sh_addr);
+		printf("sh_offset %x\n", pshdr->sh_offset);
+		printf("sh_size %x\n", pshdr->sh_size);
+		printf("sh_link %x\n", pshdr->sh_link);
+		printf("sh_info %x\n", pshdr->sh_info);
+		printf("sh_addralign %x\n", pshdr->sh_addralign);
+		printf("sh_entsize %x\n", pshdr->sh_entsize);
+	}
+#endif				/* DEBUG */
+
+#ifdef DEBUG
+	for (i = 0; i < pehdr->e_phnum; i++) {
+		pshdr = (Elf_Phdr *) (pexe + pehdr->e_phoff +
+		    (i * pehdr->e_phentsize));
+
+		printf("program header %d\n", i);
+		printf("p_type %x\n", pphdr->p_type);
+		printf("p_offset %x\n", pphdr->p_offset);
+		printf("p_vaddr %x\n", pphdr->p_vaddr);
+		printf("p_paddr %x\n", pphdr->p_paddr);
+		printf("p_filesz %x\n", pphdr->p_filesz);
+		printf("p_memsz %x\n", pphdr->p_memsz);
+		printf("p_flags %x\n", pphdr->p_flags);
+		printf("p_align %x\n", pphdr->p_align);
+	}
+#endif				/* DEBUG */
+#if 0
+	for (i = 0; i < pehdr->e_shnum; i++) {
+		pshdr = (Elf_Phdr *) (pexe + pehdr->e_shoff +
+		    (i * pehdr->e_shentsize));
+		if (strcmp(".strtab", get_shstr(pshdr->sh_name)) == 0)
+			break;
+	}
+	fprint_shstr(stdout, pshdr->sh_name);
+	printf("\n");
+#endif
+
+	load_strtab(pehdr, pexe);
+	load_symtab(pehdr, pexe);
+
+	munmap(pexe, sb.st_size);
+	close(pfile);
+}
+char           *shstrtab;
+
+void
+load_shstr_tab(Elf_Ehdr * pehdr, char *pexe)
+{
+	Elf_Shdr       *pshdr;
+	shstrtab = NULL;
+	if (pehdr->e_shstrndx == 0)
+		return;
+	pshdr = (Elf_Shdr *) (pexe + pehdr->e_shoff +
+	    (pehdr->e_shstrndx * pehdr->e_shentsize));
+
+	shstrtab = (char *) (pexe + pshdr->sh_offset);
+}
+
+void
+fprint_shstr(FILE * channel, int indx)
+{
+	if (shstrtab != NULL)
+		fprintf(channel, "\"%s\"", &(shstrtab[indx]));
+}
+
+char           *
+get_shstr(int indx)
+{
+	return &(shstrtab[indx]);
+}
+
+void
+load_symtab(Elf_Ehdr * pehdr, char *pexe)
+{
+	Elf_Sym        *symtab;
+	Elf_Shdr       *symsect;
+	int             symtabsize;
+	Elf_Shdr       *psymshdr;
+	Elf_Shdr       *pshdr;
+#ifdef DEBUG
+	char           *shname;
+#endif
+	int             i;
+
+	symtab = NULL;
+	for (i = 0; i < pehdr->e_shnum; i++) {
+		pshdr = (Elf_Shdr *) (pexe + pehdr->e_shoff +
+		    (i * pehdr->e_shentsize));
+		if (SHT_REL != pshdr->sh_type && SHT_RELA != pshdr->sh_type)
+			continue;
+		psymshdr = (Elf_Shdr *) (pexe + pehdr->e_shoff +
+		    (pshdr->sh_link * pehdr->e_shentsize));
+#ifdef DEBUG
+		fprint_shstr(stdout, pshdr->sh_name);
+		printf("\n");
+#endif
+		symtab = (Elf_Sym *) (pexe + psymshdr->sh_offset);
+		symsect = psymshdr;
+		symtabsize = psymshdr->sh_size;
+
+#ifdef DEBUG
+		dump_symtab(symsect, symtab, symtabsize);
+#endif
+		hide_sym(pehdr, symsect, symtab, symtabsize, pshdr->sh_link);
+	}
+
+}
+
+void
+dump_symtab(Elf_Shdr * symsect, Elf_Sym * symtab, int symtabsize)
+{
+	int             i;
+	Elf_Sym        *psymtab;
+
+	for (i = 0; i < (symtabsize / sizeof(Elf_Sym)); i++) {
+		psymtab = &(symtab[i]);
+		if ((psymtab->st_info & 0xf0) == 0x10 &&
+		    (psymtab->st_shndx != SHN_UNDEF)) {
+			printf("symbol %d:\n", i);
+			printf("st_name %x \"%s\"\n", psymtab->st_name,
+			    get_str(psymtab->st_name));
+			printf("st_value %x\n", psymtab->st_value);
+			printf("st_size %x\n", psymtab->st_size);
+			printf("st_info %x\n", psymtab->st_info);
+			printf("st_other %x\n", psymtab->st_other);
+			printf("st_shndx %x\n", psymtab->st_shndx);
+		}
+	}
+}
+
+char           *strtab;
+int             strtabsize;
+void
+load_strtab(Elf_Ehdr * pehdr, char *pexe)
+{
+	Elf_Shdr       *pshdr = NULL;
+	char           *shname;
+	int             i;
+	strtab = NULL;
+	for (i = 0; i < pehdr->e_shnum; i++) {
+		pshdr = (Elf_Shdr *) (pexe + pehdr->e_shoff +
+		    (i * pehdr->e_shentsize));
+
+		shname = get_shstr(pshdr->sh_name);
+		if (strcmp(".strtab", shname) == 0)
+			break;
+	}
+#ifdef DEBUG
+	fprint_shstr(stdout, pshdr->sh_name);
+	printf("\n");
+#endif
+
+	strtab = (char *) (pexe + pshdr->sh_offset);
+
+	strtabsize = pshdr->sh_size;
+
+#ifdef DEBUG
+	dump_strtab();
+#endif
+}
+
+void
+dump_strtab()
+{
+	int             index;
+	char           *pstr;
+	char           *pnstr;
+	int             i = 0;
+	index = 0;
+	pstr = strtab;
+	while (index < strtabsize) {
+		printf("string %x: \"%s\"\n", i, pstr);
+		pnstr = pstr + strlen(pstr) + 1;
+		index = pnstr - strtab;
+		pstr = pnstr;
+		i++;
+	}
+
+}
+
+void
+fprint_str(FILE * channel, int indx)
+{
+	if (strtab != NULL)
+		fprintf(channel, "\"%s\"", &(strtab[indx]));
+}
+
+char *
+get_str(int indx)
+{
+	return &(strtab[indx]);
+}
+
+int             in_keep_list(char *symbol);
+
+void
+hide_sym(Elf_Ehdr * ehdr, Elf_Shdr * symsect,
+    Elf_Sym * symtab, int symtabsize, int symtabsecnum)
+{
+	int             i;
+	unsigned char   info;
+	Elf_Sym        *psymtab;
+
+#ifdef __mips__
+	u_int32_t f = arc4random();
+#endif
+
+	for (i = 0; i < (symtabsize / sizeof(Elf_Sym)); i++) {
+		psymtab = &(symtab[i]);
+		if ((psymtab->st_info & 0xf0) == 0x10 &&
+		    (psymtab->st_shndx != SHN_UNDEF)) {
+			if (in_keep_list(get_str(psymtab->st_name)))
+				continue;
+#ifdef DEBUG
+			printf("symbol %d:\n", i);
+			printf("st_name %x \"%s\"\n", psymtab->st_name,
+			    get_str(psymtab->st_name));
+			printf("st_info %x\n", psymtab->st_info);
+#endif
+#ifndef __mips__
+			info = psymtab->st_info;
+			info = info & 0xf;
+			psymtab->st_info = info;
+#else
+			/*
+			 * XXX This is a small ugly hack to be able to use
+			 * XXX chrunchide with MIPS.
+			 * XXX Because MIPS needs global symbols to stay
+			 * XXX global (has to do with GOT), we mess around
+			 * XXX with the symbol names instead. For most uses
+			 * XXX this will be no problem, symbols are stripped
+			 * XXX anyway. However, if many one character
+			 * XXX symbols exist, names may clash.
+			 */
+			{
+				char *p;
+				u_int32_t n, z;
+
+				z = f++;
+				p = get_str(psymtab->st_name);
+				n = strlen(p);
+				if (n > 4)
+					n = 4;
+				while (n--) {
+					p[n] = z;
+					z >>= 8;
+					while (p[n] == 0)
+						p[n] += arc4random();
+				}
+			}
+
+#endif
+#ifdef DEBUG
+			printf("st_info %x\n", psymtab->st_info);
+#endif
+		}
+	}
+	reorder_syms(ehdr, symsect, symtab, symtabsize, symtabsecnum);
+}
+
+void
+reorder_syms(Elf_Ehdr * ehdr, Elf_Shdr * symsect,
+    Elf_Sym * symtab, int symtabsize, int symtabsecnum)
+{
+	int             i;
+	int             nsyms;
+	int             cursym;
+	Elf_Sym        *tmpsymtab;
+	Symmap         *symmap;
+
+
+	nsyms = symtabsize / sizeof(Elf_Sym);
+
+	tmpsymtab = (Elf_Sym *) calloc(1, symtabsize);
+	symmap = (Symmap *) calloc(nsyms, sizeof(Symmap));
+	if (!tmpsymtab || !symmap)
+		errx(5, "calloc: %s", strerror(ENOMEM));
+
+	bcopy(symtab, tmpsymtab, symtabsize);
+
+	cursym = 1;
+	for (i = 1; i < nsyms; i++) {
+		if ((tmpsymtab[i].st_info & 0xf0) == 0x00) {
+#ifdef DEBUG
+			printf("copying  l o%d n%d <%s>\n", i, cursym,
+			    get_str(tmpsymtab[i].st_name));
+#endif
+			bcopy(&(tmpsymtab[i]), &(symtab[cursym]),
+			    sizeof(Elf_Sym));
+			symmap[i] = cursym;
+			cursym++;
+		}
+	}
+	symsect->sh_info = cursym;
+	for (i = 1; i < nsyms; i++) {
+		if ((tmpsymtab[i].st_info & 0xf0) != 0x00) {
+#ifdef DEBUG
+			printf("copying nl o%d n%d <%s>\n", i, cursym,
+			    get_str(tmpsymtab[i].st_name));
+#endif
+			bcopy(&(tmpsymtab[i]), &(symtab[cursym]),
+			    sizeof(Elf_Sym));
+			symmap[i] = cursym;
+			cursym++;
+		}
+	}
+	if (cursym != nsyms) {
+		printf("miscounted symbols somewhere c %d n %d \n",
+		    cursym, nsyms);
+		exit(5);
+	}
+	renum_reloc_syms(ehdr, symmap, symtabsecnum);
+	free(tmpsymtab);
+	free(symmap);
+}
+
+void
+renum_reloc_syms(Elf_Ehdr * ehdr, Symmap * symmap, int symtabsecnum)
+{
+	Elf_Shdr       *pshdr;
+	int             i, j;
+	int             num_reloc;
+	Elf_Rel        *prel;
+	Elf_RelA       *prela;
+	int             symnum;
+
+	for (i = 0; i < ehdr->e_shnum; i++) {
+		pshdr = (Elf_Shdr *) (pexe + ehdr->e_shoff +
+		    (i * ehdr->e_shentsize));
+		if ((pshdr->sh_type == SHT_RELA) &&
+		    pshdr->sh_link == symtabsecnum) {
+
+#ifdef DEBUG
+			printf("section %d has rela relocations in symtab\n", i);
+#endif
+			prela = (Elf_RelA *) (pexe + pshdr->sh_offset);
+			num_reloc = pshdr->sh_size / sizeof(Elf_RelA);
+			for (j = 0; j < num_reloc; j++) {
+				symnum = ELF_R_SYM(prela[j].r_info);
+#ifdef DEBUG
+				printf("sym num o %d n %d\n", symnum,
+				    symmap[symnum]);
+#endif
+				prela[j].r_info = ELF_R_INFO(symmap[symnum],
+				    ELF_R_TYPE(prela[j].r_info));
+			}
+		}
+		if ((pshdr->sh_type == SHT_REL) &&
+		    pshdr->sh_link == symtabsecnum) {
+#ifdef DEBUG
+			printf("section %d has rel relocations in symtab\n", i);
+#endif
+			prel = (Elf_Rel *) (pexe + pshdr->sh_offset);
+			num_reloc = pshdr->sh_size / sizeof(Elf_Rel);
+			for (j = 0; j < num_reloc; j++) {
+				symnum = ELF_R_SYM(prel[j].r_info);
+#ifdef DEBUG
+				printf("sym num o %d n %d\n", symnum,
+				    symmap[symnum]);
+#endif
+				prel[j].r_info = ELF_R_INFO(symmap[symnum],
+				    ELF_R_TYPE(prel[j].r_info));
+			}
+		}
+	}
+
+}
+#endif				/* _NLIST_DO_ELF */