/* 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. */ void memcpy_to_target(target_ulong dest, const void *src, unsigned long len) { void *host_ptr; host_ptr = lock_user(dest, len, 0); memcpy(host_ptr, src, len); unlock_user(host_ptr, dest, 1); } 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. */ target_ulong loader_build_argptr(int envc, int argc, target_ulong sp, target_ulong stringp, int push_ptr) { int n = sizeof(target_ulong); target_ulong envp; target_ulong argv; sp -= (envc + 1) * n; envp = sp; sp -= (argc + 1) * n; argv = sp; if (push_ptr) { sp -= n; tputl(sp, envp); sp -= n; tputl(sp, argv); } sp -= n; tputl(sp, argc); while (argc-- > 0) { tputl(argv, stringp); argv += n; stringp += target_strlen(stringp) + 1; } tputl(argv, 0); while (envc-- > 0) { tputl(envp, stringp); envp += n; stringp += target_strlen(stringp) + 1; } tputl(envp, 0); 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') { 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); }