/* 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; } } retval = read(bprm->fd, bprm->buf, BPRM_BUF_SIZE); if (retval < 0) { perror("prepare_binprm"); exit(-1); } if (retval < BPRM_BUF_SIZE) { /* Make sure the rest of the loader won't read garbage. */ memset(bprm->buf + retval, 0, BPRM_BUF_SIZE - retval); } 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) { TaskState *ts = (TaskState *)thread_env->opaque; 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); ts->info->arg_start = stringp; while (argc-- > 0) { /* FIXME - handle put_user() failures */ put_user_ual(stringp, argv); argv += n; stringp += target_strlen(stringp) + 1; } ts->info->arg_end = stringp; /* 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); memset(bprm->page, 0, sizeof(bprm->page)); 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); if(retval>=0) { if (bprm->buf[0] == 0x7f && bprm->buf[1] == 'E' && bprm->buf[2] == 'L' && bprm->buf[3] == 'F') { retval = load_elf_binary(bprm, regs, infop); #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); }