/* Code for loading Linux executables.  Mostly linux kernel code.  */#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <errno.h>#include <unistd.h>#include <stdio.h>#include <stdlib.h>#include "qemu.h"#define NGROUPS 32/* ??? This should really be somewhere else.  */abi_long memcpy_to_target(abi_ulong dest, const void *src,                          unsigned long len){    void *host_ptr;    host_ptr = lock_user(VERIFY_WRITE, dest, len, 0);    if (!host_ptr)        return -TARGET_EFAULT;    memcpy(host_ptr, src, len);    unlock_user(host_ptr, dest, 1);    return 0;}static int in_group_p(gid_t g){    /* return TRUE if we're in the specified group, FALSE otherwise */    int		ngroup;    int		i;    gid_t	grouplist[NGROUPS];    ngroup = getgroups(NGROUPS, grouplist);    for(i = 0; i < ngroup; i++) {	if(grouplist[i] == g) {	    return 1;	}    }    return 0;}static int count(char ** vec){    int		i;    for(i = 0; *vec; i++) {        vec++;    }    return(i);}static int prepare_binprm(struct linux_binprm *bprm){    struct stat		st;    int mode;    int retval, id_change;    if(fstat(bprm->fd, &st) < 0) {	return(-errno);    }    mode = st.st_mode;    if(!S_ISREG(mode)) {	/* Must be regular file */	return(-EACCES);    }    if(!(mode & 0111)) {	/* Must have at least one execute bit set */	return(-EACCES);    }    bprm->e_uid = geteuid();    bprm->e_gid = getegid();    id_change = 0;    /* Set-uid? */    if(mode & S_ISUID) {    	bprm->e_uid = st.st_uid;	if(bprm->e_uid != geteuid()) {	    id_change = 1;	}    }    /* Set-gid? */    /*     * If setgid is set but no group execute bit then this     * is a candidate for mandatory locking, not a setgid     * executable.     */    if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {	bprm->e_gid = st.st_gid;	if (!in_group_p(bprm->e_gid)) {		id_change = 1;	}    }    memset(bprm->buf, 0, sizeof(bprm->buf));    retval = lseek(bprm->fd, 0L, SEEK_SET);    if(retval >= 0) {        retval = read(bprm->fd, bprm->buf, 128);    }    if(retval < 0) {	perror("prepare_binprm");	exit(-1);	/* return(-errno); */    }    else {	return(retval);    }}/* Construct the envp and argv tables on the target stack.  */abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,                              abi_ulong stringp, int push_ptr){    int n = sizeof(abi_ulong);    abi_ulong envp;    abi_ulong argv;    sp -= (envc + 1) * n;    envp = sp;    sp -= (argc + 1) * n;    argv = sp;    if (push_ptr) {        /* FIXME - handle put_user() failures */        sp -= n;        put_user_ual(envp, sp);        sp -= n;        put_user_ual(argv, sp);    }    sp -= n;    /* FIXME - handle put_user() failures */    put_user_ual(argc, sp);    while (argc-- > 0) {        /* FIXME - handle put_user() failures */        put_user_ual(stringp, argv);        argv += n;        stringp += target_strlen(stringp) + 1;    }    /* FIXME - handle put_user() failures */    put_user_ual(0, argv);    while (envc-- > 0) {        /* FIXME - handle put_user() failures */        put_user_ual(stringp, envp);        envp += n;        stringp += target_strlen(stringp) + 1;    }    /* FIXME - handle put_user() failures */    put_user_ual(0, envp);    return sp;}int loader_exec(const char * filename, char ** argv, char ** envp,             struct target_pt_regs * regs, struct image_info *infop){    struct linux_binprm bprm;    int retval;    int i;    bprm.p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);    for (i=0 ; i<MAX_ARG_PAGES ; i++)       /* clear page-table */            bprm.page[i] = 0;    retval = open(filename, O_RDONLY);    if (retval < 0)        return retval;    bprm.fd = retval;    bprm.filename = (char *)filename;    bprm.argc = count(argv);    bprm.argv = argv;    bprm.envc = count(envp);    bprm.envp = envp;    retval = prepare_binprm(&bprm);    infop->host_argv = argv;    if(retval>=0) {        if (bprm.buf[0] == 0x7f                && bprm.buf[1] == 'E'                && bprm.buf[2] == 'L'                && bprm.buf[3] == 'F') {#ifndef TARGET_HAS_ELFLOAD32            retval = load_elf_binary(&bprm,regs,infop);#else            retval = load_elf_binary_multi(&bprm, regs, infop);#endif#if defined(TARGET_HAS_BFLT)        } else if (bprm.buf[0] == 'b'                && bprm.buf[1] == 'F'                && bprm.buf[2] == 'L'                && bprm.buf[3] == 'T') {            retval = load_flt_binary(&bprm,regs,infop);#endif        } else {            fprintf(stderr, "Unknown binary format\n");            return -1;        }    }    if(retval>=0) {        /* success.  Initialize important registers */        do_init_thread(regs, infop);        return retval;    }    /* Something went wrong, return the inode and free the argument pages*/    for (i=0 ; i<MAX_ARG_PAGES ; i++) {        free(bprm.page[i]);    }    return(retval);}