/* * Syscall wrappers to ensure that nothing gets done in dry_run mode * and to handle system peculiarities. * * Copyright (C) 1998 Andrew Tridgell * Copyright (C) 2002 Martin Pool * Copyright (C) 2003-2022 Wayne Davison * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, visit the http://fsf.org website. */ #include "rsync.h" #if !defined MKNOD_CREATES_SOCKETS && defined HAVE_SYS_UN_H #include #endif #ifdef HAVE_SYS_ATTR_H #include #endif #if defined HAVE_SYS_FALLOCATE && !defined HAVE_FALLOCATE #include #endif extern int dry_run; extern int am_root; extern int am_sender; extern int read_only; extern int list_only; extern int inplace; extern int preallocate_files; extern int preserve_perms; extern int preserve_executability; extern int open_noatime; #ifndef S_BLKSIZE # if defined hpux || defined __hpux__ || defined __hpux # define S_BLKSIZE 1024 # elif defined _AIX && defined _I386 # define S_BLKSIZE 4096 # else # define S_BLKSIZE 512 # endif #endif #ifdef SUPPORT_CRTIMES #ifdef HAVE_GETATTRLIST #pragma pack(push, 4) struct create_time { uint32 length; struct timespec crtime; }; #pragma pack(pop) #elif defined __CYGWIN__ #include #endif #endif #define RETURN_ERROR_IF(x,e) \ do { \ if (x) { \ errno = (e); \ return -1; \ } \ } while (0) #define RETURN_ERROR_IF_RO_OR_LO RETURN_ERROR_IF(read_only || list_only, EROFS) int do_unlink(const char *path) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; return unlink(path); } #ifdef SUPPORT_LINKS int do_symlink(const char *lnk, const char *path) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS /* For --fake-super, we create a normal file with mode 0600 * and write the lnk into it. */ if (am_root < 0) { int ok, len = strlen(lnk); int fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR); if (fd < 0) return -1; ok = write(fd, lnk, len) == len; if (close(fd) < 0) ok = 0; return ok ? 0 : -1; } #endif return symlink(lnk, path); } #if defined NO_SYMLINK_XATTRS || defined NO_SYMLINK_USER_XATTRS ssize_t do_readlink(const char *path, char *buf, size_t bufsiz) { /* For --fake-super, we read the link from the file. */ if (am_root < 0) { int fd = do_open_nofollow(path, O_RDONLY); if (fd >= 0) { int len = read(fd, buf, bufsiz); close(fd); return len; } if (errno != ELOOP) return -1; /* A real symlink needs to be turned into a fake one on the receiving * side, so tell the generator that the link has no length. */ if (!am_sender) return 0; /* Otherwise fall through and let the sender report the real length. */ } return readlink(path, buf, bufsiz); } #endif #endif #if defined HAVE_LINK || defined HAVE_LINKAT int do_link(const char *old_path, const char *new_path) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; #ifdef HAVE_LINKAT return linkat(AT_FDCWD, old_path, AT_FDCWD, new_path, 0); #else return link(old_path, new_path); #endif } #endif int do_lchown(const char *path, uid_t owner, gid_t group) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; #ifndef HAVE_LCHOWN #define lchown chown #endif return lchown(path, owner, group); } int do_mknod(const char *pathname, mode_t mode, dev_t dev) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; /* For --fake-super, we create a normal file with mode 0600. */ if (am_root < 0) { int fd = open(pathname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR); if (fd < 0 || close(fd) < 0) return -1; return 0; } #if !defined MKNOD_CREATES_FIFOS && defined HAVE_MKFIFO if (S_ISFIFO(mode)) return mkfifo(pathname, mode); #endif #if !defined MKNOD_CREATES_SOCKETS && defined HAVE_SYS_UN_H if (S_ISSOCK(mode)) { int sock; struct sockaddr_un saddr; unsigned int len = strlcpy(saddr.sun_path, pathname, sizeof saddr.sun_path); if (len >= sizeof saddr.sun_path) { errno = ENAMETOOLONG; return -1; } #ifdef HAVE_SOCKADDR_UN_LEN saddr.sun_len = len + 1; #endif saddr.sun_family = AF_UNIX; if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0 || (unlink(pathname) < 0 && errno != ENOENT) || (bind(sock, (struct sockaddr*)&saddr, sizeof saddr)) < 0) return -1; close(sock); #ifdef HAVE_CHMOD return do_chmod(pathname, mode); #else return 0; #endif } #endif #ifdef HAVE_MKNOD return mknod(pathname, mode, dev); #else return -1; #endif } int do_rmdir(const char *pathname) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; return rmdir(pathname); } int do_open(const char *pathname, int flags, mode_t mode) { if (flags != O_RDONLY) { RETURN_ERROR_IF(dry_run, 0); RETURN_ERROR_IF_RO_OR_LO; } #ifdef O_NOATIME if (open_noatime) flags |= O_NOATIME; #endif return open(pathname, flags | O_BINARY, mode); } #ifdef HAVE_CHMOD int do_chmod(const char *path, mode_t mode) { static int switch_step = 0; int code; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; switch (switch_step) { #ifdef HAVE_LCHMOD case 0: if ((code = lchmod(path, mode & CHMOD_BITS)) == 0) break; if (errno == ENOSYS) switch_step++; else if (errno != ENOTSUP) break; #endif /* FALLTHROUGH */ default: if (S_ISLNK(mode)) { # if defined HAVE_SETATTRLIST struct attrlist attrList; uint32_t m = mode & CHMOD_BITS; /* manpage is wrong: not mode_t! */ memset(&attrList, 0, sizeof attrList); attrList.bitmapcount = ATTR_BIT_MAP_COUNT; attrList.commonattr = ATTR_CMN_ACCESSMASK; if ((code = setattrlist(path, &attrList, &m, sizeof m, FSOPT_NOFOLLOW)) == 0) break; if (errno == ENOTSUP) code = 1; # else code = 1; # endif } else code = chmod(path, mode & CHMOD_BITS); /* DISCOURAGED FUNCTION */ break; } if (code != 0 && (preserve_perms || preserve_executability)) return code; return 0; } #endif int do_rename(const char *old_path, const char *new_path) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; return rename(old_path, new_path); } #ifdef HAVE_FTRUNCATE int do_ftruncate(int fd, OFF_T size) { int ret; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; do { ret = ftruncate(fd, size); } while (ret < 0 && errno == EINTR); return ret; } #endif void trim_trailing_slashes(char *name) { int l; /* Some BSD systems cannot make a directory if the name * contains a trailing slash. * */ /* Don't change empty string; and also we can't improve on * "/" */ l = strlen(name); while (l > 1) { if (name[--l] != '/') break; name[l] = '\0'; } } int do_mkdir(char *path, mode_t mode) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; trim_trailing_slashes(path); return mkdir(path, mode); } /* like mkstemp but forces permissions */ int do_mkstemp(char *template, mode_t perms) { RETURN_ERROR_IF(dry_run, 0); RETURN_ERROR_IF(read_only, EROFS); perms |= S_IWUSR; #if defined HAVE_SECURE_MKSTEMP && defined HAVE_FCHMOD && (!defined HAVE_OPEN64 || defined HAVE_MKSTEMP64) { int fd = mkstemp(template); if (fd == -1) return -1; if (fchmod(fd, perms) != 0 && preserve_perms) { int errno_save = errno; close(fd); unlink(template); errno = errno_save; return -1; } #if defined HAVE_SETMODE && O_BINARY setmode(fd, O_BINARY); #endif return fd; } #else if (!mktemp(template)) return -1; return do_open(template, O_RDWR|O_EXCL|O_CREAT, perms); #endif } int do_stat(const char *path, STRUCT_STAT *st) { #ifdef USE_STAT64_FUNCS return stat64(path, st); #else return stat(path, st); #endif } int do_lstat(const char *path, STRUCT_STAT *st) { #ifdef SUPPORT_LINKS # ifdef USE_STAT64_FUNCS return lstat64(path, st); # else return lstat(path, st); # endif #else return do_stat(path, st); #endif } int do_fstat(int fd, STRUCT_STAT *st) { #ifdef USE_STAT64_FUNCS return fstat64(fd, st); #else return fstat(fd, st); #endif } OFF_T do_lseek(int fd, OFF_T offset, int whence) { #ifdef HAVE_LSEEK64 #if !SIZEOF_OFF64_T OFF_T lseek64(); #else off64_t lseek64(); #endif return lseek64(fd, offset, whence); #else return lseek(fd, offset, whence); #endif } #ifdef HAVE_SETATTRLIST int do_setattrlist_times(const char *path, STRUCT_STAT *stp) { struct attrlist attrList; struct timespec ts[2]; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; /* Yes, this is in the opposite order of utime and similar. */ ts[0].tv_sec = stp->st_mtime; ts[0].tv_nsec = stp->ST_MTIME_NSEC; ts[1].tv_sec = stp->st_atime; ts[1].tv_nsec = stp->ST_ATIME_NSEC; memset(&attrList, 0, sizeof attrList); attrList.bitmapcount = ATTR_BIT_MAP_COUNT; attrList.commonattr = ATTR_CMN_MODTIME | ATTR_CMN_ACCTIME; return setattrlist(path, &attrList, ts, sizeof ts, FSOPT_NOFOLLOW); } #ifdef SUPPORT_CRTIMES int do_setattrlist_crtime(const char *path, time_t crtime) { struct attrlist attrList; struct timespec ts; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; ts.tv_sec = crtime; ts.tv_nsec = 0; memset(&attrList, 0, sizeof attrList); attrList.bitmapcount = ATTR_BIT_MAP_COUNT; attrList.commonattr = ATTR_CMN_CRTIME; return setattrlist(path, &attrList, &ts, sizeof ts, FSOPT_NOFOLLOW); } #endif #endif /* HAVE_SETATTRLIST */ #ifdef SUPPORT_CRTIMES time_t get_create_time(const char *path, STRUCT_STAT *stp) { #ifdef HAVE_GETATTRLIST static struct create_time attrBuf; struct attrlist attrList; (void)stp; memset(&attrList, 0, sizeof attrList); attrList.bitmapcount = ATTR_BIT_MAP_COUNT; attrList.commonattr = ATTR_CMN_CRTIME; if (getattrlist(path, &attrList, &attrBuf, sizeof attrBuf, FSOPT_NOFOLLOW) < 0) return 0; return attrBuf.crtime.tv_sec; #elif defined __CYGWIN__ (void)path; return stp->st_birthtime; #else #error Unknown crtimes implementation #endif } #if defined __CYGWIN__ int do_SetFileTime(const char *path, time_t crtime) { if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; int cnt = MultiByteToWideChar(CP_UTF8, 0, path, -1, NULL, 0); if (cnt == 0) return -1; WCHAR *pathw = new_array(WCHAR, cnt); if (!pathw) return -1; MultiByteToWideChar(CP_UTF8, 0, path, -1, pathw, cnt); HANDLE handle = CreateFileW(pathw, FILE_WRITE_ATTRIBUTES, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL); free(pathw); if (handle == INVALID_HANDLE_VALUE) return -1; int64 temp_time = Int32x32To64(crtime, 10000000) + 116444736000000000LL; FILETIME birth_time; birth_time.dwLowDateTime = (DWORD)temp_time; birth_time.dwHighDateTime = (DWORD)(temp_time >> 32); int ok = SetFileTime(handle, &birth_time, NULL, NULL); CloseHandle(handle); return ok ? 0 : -1; } #endif #endif /* SUPPORT_CRTIMES */ #ifdef HAVE_UTIMENSAT int do_utimensat(const char *path, STRUCT_STAT *stp) { struct timespec t[2]; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; t[0].tv_sec = stp->st_atime; #ifdef ST_ATIME_NSEC t[0].tv_nsec = stp->ST_ATIME_NSEC; #else t[0].tv_nsec = 0; #endif t[1].tv_sec = stp->st_mtime; #ifdef ST_MTIME_NSEC t[1].tv_nsec = stp->ST_MTIME_NSEC; #else t[1].tv_nsec = 0; #endif return utimensat(AT_FDCWD, path, t, AT_SYMLINK_NOFOLLOW); } #endif #ifdef HAVE_LUTIMES int do_lutimes(const char *path, STRUCT_STAT *stp) { struct timeval t[2]; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; t[0].tv_sec = stp->st_atime; #ifdef ST_ATIME_NSEC t[0].tv_usec = stp->ST_ATIME_NSEC / 1000; #else t[0].tv_usec = 0; #endif t[1].tv_sec = stp->st_mtime; #ifdef ST_MTIME_NSEC t[1].tv_usec = stp->ST_MTIME_NSEC / 1000; #else t[1].tv_usec = 0; #endif return lutimes(path, t); } #endif #ifdef HAVE_UTIMES int do_utimes(const char *path, STRUCT_STAT *stp) { struct timeval t[2]; if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; t[0].tv_sec = stp->st_atime; #ifdef ST_ATIME_NSEC t[0].tv_usec = stp->ST_ATIME_NSEC / 1000; #else t[0].tv_usec = 0; #endif t[1].tv_sec = stp->st_mtime; #ifdef ST_MTIME_NSEC t[1].tv_usec = stp->ST_MTIME_NSEC / 1000; #else t[1].tv_usec = 0; #endif return utimes(path, t); } #elif defined HAVE_UTIME int do_utime(const char *path, STRUCT_STAT *stp) { #ifdef HAVE_STRUCT_UTIMBUF struct utimbuf tbuf; #else time_t t[2]; #endif if (dry_run) return 0; RETURN_ERROR_IF_RO_OR_LO; # ifdef HAVE_STRUCT_UTIMBUF tbuf.actime = stp->st_atime; tbuf.modtime = stp->st_mtime; return utime(path, &tbuf); # else t[0] = stp->st_atime; t[1] = stp->st_mtime; return utime(path, t); # endif } #else #error Need utimes or utime function. #endif #ifdef SUPPORT_PREALLOCATION #ifdef FALLOC_FL_KEEP_SIZE #define DO_FALLOC_OPTIONS FALLOC_FL_KEEP_SIZE #else #define DO_FALLOC_OPTIONS 0 #endif OFF_T do_fallocate(int fd, OFF_T offset, OFF_T length) { int opts = inplace || preallocate_files ? DO_FALLOC_OPTIONS : 0; int ret; RETURN_ERROR_IF(dry_run, 0); RETURN_ERROR_IF_RO_OR_LO; if (length & 1) /* make the length not match the desired length */ length++; else length--; #if defined HAVE_FALLOCATE ret = fallocate(fd, opts, offset, length); #elif defined HAVE_SYS_FALLOCATE ret = syscall(SYS_fallocate, fd, opts, (loff_t)offset, (loff_t)length); #elif defined HAVE_EFFICIENT_POSIX_FALLOCATE ret = posix_fallocate(fd, offset, length); #else #error Coding error in SUPPORT_PREALLOCATION logic. #endif if (ret < 0) return ret; if (opts == 0) { STRUCT_STAT st; if (do_fstat(fd, &st) < 0) return length; return st.st_blocks * S_BLKSIZE; } return 0; } #endif /* Punch a hole at pos for len bytes. The current file position must be at pos and will be * changed to be at pos + len. */ int do_punch_hole(int fd, OFF_T pos, OFF_T len) { #ifdef HAVE_FALLOCATE # ifdef HAVE_FALLOC_FL_PUNCH_HOLE if (fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, pos, len) == 0) { if (do_lseek(fd, len, SEEK_CUR) != pos + len) return -1; return 0; } # endif # ifdef HAVE_FALLOC_FL_ZERO_RANGE if (fallocate(fd, FALLOC_FL_ZERO_RANGE, pos, len) == 0) { if (do_lseek(fd, len, SEEK_CUR) != pos + len) return -1; return 0; } # endif #else (void)pos; #endif { char zeros[4096]; memset(zeros, 0, sizeof zeros); while (len > 0) { int chunk = len > (int)sizeof zeros ? (int)sizeof zeros : len; int wrote = write(fd, zeros, chunk); if (wrote <= 0) { if (wrote < 0 && errno == EINTR) continue; return -1; } len -= wrote; } } return 0; } int do_open_nofollow(const char *pathname, int flags) { #ifndef O_NOFOLLOW STRUCT_STAT f_st, l_st; #endif int fd; if (flags != O_RDONLY) { RETURN_ERROR_IF(dry_run, 0); RETURN_ERROR_IF_RO_OR_LO; #ifndef O_NOFOLLOW /* This function doesn't support write attempts w/o O_NOFOLLOW. */ errno = EINVAL; return -1; #endif } #ifdef O_NOFOLLOW fd = open(pathname, flags|O_NOFOLLOW); #else if (do_lstat(pathname, &l_st) < 0) return -1; if (S_ISLNK(l_st.st_mode)) { errno = ELOOP; return -1; } if ((fd = open(pathname, flags)) < 0) return fd; if (do_fstat(fd, &f_st) < 0) { close_and_return_error: { int save_errno = errno; close(fd); errno = save_errno; } return -1; } if (l_st.st_dev != f_st.st_dev || l_st.st_ino != f_st.st_ino) { errno = EINVAL; goto close_and_return_error; } #endif return fd; }