bsd-user/bsdload.c

   1 /* Code for loading BSD executables.  Mostly linux kernel code.  */
   2
   3 #include "qemu/osdep.h"
   4
   5 #include "qemu.h"
   6
   7 #define TARGET_NGROUPS 32
   8
   9 /* ??? This should really be somewhere else.  */
  10 abi_long memcpy_to_target(abi_ulong dest, const void *src,
  11                           unsigned long len)
  12 {
  13     void *host_ptr;
  14
  15     host_ptr = lock_user(VERIFY_WRITE, dest, len, 0);
  16     if (!host_ptr)
  17         return -TARGET_EFAULT;
  18     memcpy(host_ptr, src, len);
  19     unlock_user(host_ptr, dest, 1);
  20     return 0;
  21 }
  22
  23 static int count(char ** vec)
  24 {
  25     int         i;
  26
  27     for(i = 0; *vec; i++) {
  28         vec++;
  29     }
  30
  31     return(i);
  32 }
  33
  34 static int prepare_binprm(struct linux_binprm *bprm)
  35 {
  36     struct stat         st;
  37     int mode;
  38     int retval;
  39
  40     if(fstat(bprm->fd, &st) < 0) {
  41         return(-errno);
  42     }
  43
  44     mode = st.st_mode;
  45     if(!S_ISREG(mode)) {        /* Must be regular file */
  46         return(-EACCES);
  47     }
  48     if(!(mode & 0111)) {        /* Must have at least one execute bit set */
  49         return(-EACCES);
  50     }
  51
  52     bprm->e_uid = geteuid();
  53     bprm->e_gid = getegid();
  54
  55     /* Set-uid? */
  56     if(mode & S_ISUID) {
  57         bprm->e_uid = st.st_uid;
  58     }
  59
  60     /* Set-gid? */
  61     /*
  62      * If setgid is set but no group execute bit then this
  63      * is a candidate for mandatory locking, not a setgid
  64      * executable.
  65      */
  66     if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
  67         bprm->e_gid = st.st_gid;
  68     }
  69
  70     memset(bprm->buf, 0, sizeof(bprm->buf));
  71     retval = lseek(bprm->fd, 0L, SEEK_SET);
  72     if(retval >= 0) {
  73         retval = read(bprm->fd, bprm->buf, 128);
  74     }
  75     if(retval < 0) {
  76         perror("prepare_binprm");
  77         exit(-1);
  78         /* return(-errno); */
  79     }
  80     else {
  81         return(retval);
  82     }
  83 }
  84
  85 /* Construct the envp and argv tables on the target stack.  */
  86 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
  87                               abi_ulong stringp, int push_ptr)
  88 {
  89     int n = sizeof(abi_ulong);
  90     abi_ulong envp;
  91     abi_ulong argv;
  92
  93     sp -= (envc + 1) * n;
  94     envp = sp;
  95     sp -= (argc + 1) * n;
  96     argv = sp;
  97     if (push_ptr) {
  98         /* FIXME - handle put_user() failures */
  99         sp -= n;
 100         put_user_ual(envp, sp);
 101         sp -= n;
 102         put_user_ual(argv, sp);
 103     }
 104     sp -= n;
 105     /* FIXME - handle put_user() failures */
 106     put_user_ual(argc, sp);
 107
 108     while (argc-- > 0) {
 109         /* FIXME - handle put_user() failures */
 110         put_user_ual(stringp, argv);
 111         argv += n;
 112         stringp += target_strlen(stringp) + 1;
 113     }
 114     /* FIXME - handle put_user() failures */
 115     put_user_ual(0, argv);
 116     while (envc-- > 0) {
 117         /* FIXME - handle put_user() failures */
 118         put_user_ual(stringp, envp);
 119         envp += n;
 120         stringp += target_strlen(stringp) + 1;
 121     }
 122     /* FIXME - handle put_user() failures */
 123     put_user_ual(0, envp);
 124
 125     return sp;
 126 }
 127
 128 int loader_exec(const char * filename, char ** argv, char ** envp,
 129              struct target_pt_regs * regs, struct image_info *infop)
 130 {
 131     struct linux_binprm bprm;
 132     int retval;
 133     int i;
 134
 135     bprm.p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);
 136     for (i=0 ; i<MAX_ARG_PAGES ; i++)       /* clear page-table */
 137             bprm.page[i] = NULL;
 138     retval = open(filename, O_RDONLY);
 139     if (retval < 0)
 140         return retval;
 141     bprm.fd = retval;
 142     bprm.filename = (char *)filename;
 143     bprm.argc = count(argv);
 144     bprm.argv = argv;
 145     bprm.envc = count(envp);
 146     bprm.envp = envp;
 147
 148     retval = prepare_binprm(&bprm);
 149
 150     if(retval>=0) {
 151         if (bprm.buf[0] == 0x7f
 152                 && bprm.buf[1] == 'E'
 153                 && bprm.buf[2] == 'L'
 154                 && bprm.buf[3] == 'F') {
 155             retval = load_elf_binary(&bprm,regs,infop);
 156         } else {
 157             fprintf(stderr, "Unknown binary format\n");
 158             return -1;
 159         }
 160     }
 161
 162     if(retval>=0) {
 163         /* success.  Initialize important registers */
 164         do_init_thread(regs, infop);
 165         return retval;
 166     }
 167
 168     /* Something went wrong, return the inode and free the argument pages*/
 169     for (i=0 ; i<MAX_ARG_PAGES ; i++) {
 170         g_free(bprm.page[i]);
 171     }
 172     return(retval);
 173 }