added the --safe-links option to disallow symlinks outside the

[rsync/rsync.git] / flist.c

/* 
   Copyright (C) Andrew Tridgell 1996
   Copyright (C) Paul Mackerras 1996
   
   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 2 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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* generate and receive file lists */

#include "rsync.h"

extern struct stats stats;

extern int csum_length;

extern int verbose;
extern int am_server;
extern int always_checksum;

extern int cvs_exclude;

extern int recurse;

extern int one_file_system;
extern int make_backups;
extern int preserve_links;
extern int preserve_hard_links;
extern int preserve_perms;
extern int preserve_devices;
extern int preserve_uid;
extern int preserve_gid;
extern int preserve_times;
extern int relative_paths;
extern int copy_links;
extern int remote_version;
extern int io_error;

static struct exclude_struct **local_exclude_list;

int link_stat(const char *Path, STRUCT_STAT *Buffer) 
{
#if SUPPORT_LINKS
    if (copy_links) {
	return do_stat(Path, Buffer);
    } else {
	return do_lstat(Path, Buffer);
    }
#else
    return do_stat(Path, Buffer);
#endif
}

/*
  This function is used to check if a file should be included/excluded
  from the list of files based on its name and type etc
 */
static int match_file_name(char *fname,STRUCT_STAT *st)
{
  if (check_exclude(fname,local_exclude_list,st)) {
    if (verbose > 2)
      rprintf(FINFO,"excluding file %s\n",fname);
    return 0;
  }
  return 1;
}

/* used by the one_file_system code */
static dev_t filesystem_dev;

static void set_filesystem(char *fname)
{
  STRUCT_STAT st;
  if (link_stat(fname,&st) != 0) return;
  filesystem_dev = st.st_dev;
}


static void send_directory(int f,struct file_list *flist,char *dir);

static char *flist_dir;


void send_file_entry(struct file_struct *file,int f,unsigned base_flags)
{
  unsigned char flags;
  static time_t last_time;
  static mode_t last_mode;
  static dev_t last_rdev;
  static uid_t last_uid;
  static gid_t last_gid;
  static char lastname[MAXPATHLEN];
  char *fname;
  int l1,l2;

  if (f == -1) return;

  if (!file) {
    write_byte(f,0);
    return;
  }

  fname = f_name(file);

  flags = base_flags;

  if (file->mode == last_mode) flags |= SAME_MODE;
  if (file->rdev == last_rdev) flags |= SAME_RDEV;
  if (file->uid == last_uid) flags |= SAME_UID;
  if (file->gid == last_gid) flags |= SAME_GID;
  if (file->modtime == last_time) flags |= SAME_TIME;

  for (l1=0;lastname[l1] && (fname[l1] == lastname[l1]) && (l1 < 255);l1++) ;  
  l2 = strlen(fname) - l1;

  if (l1 > 0) flags |= SAME_NAME;
  if (l2 > 255) flags |= LONG_NAME;

  /* we must make sure we don't send a zero flags byte or the other
     end will terminate the flist transfer */
  if (flags == 0 && !S_ISDIR(file->mode)) flags |= FLAG_DELETE;
  if (flags == 0) flags |= LONG_NAME;

  write_byte(f,flags);  
  if (flags & SAME_NAME)
    write_byte(f,l1);
  if (flags & LONG_NAME)
    write_int(f,l2);
  else
    write_byte(f,l2);
  write_buf(f,fname+l1,l2);

  write_longint(f,file->length);
  if (!(flags & SAME_TIME))
    write_int(f,(int)file->modtime);
  if (!(flags & SAME_MODE))
    write_int(f,(int)file->mode);
  if (preserve_uid && !(flags & SAME_UID)) {
	  add_uid(file->uid);
	  write_int(f,(int)file->uid);
  }
  if (preserve_gid && !(flags & SAME_GID)) {
	  add_gid(file->gid);
	  write_int(f,(int)file->gid);
  }
  if (preserve_devices && IS_DEVICE(file->mode) && !(flags & SAME_RDEV))
    write_int(f,(int)file->rdev);

#if SUPPORT_LINKS
  if (preserve_links && S_ISLNK(file->mode)) {
    write_int(f,strlen(file->link));
    write_buf(f,file->link,strlen(file->link));
  }
#endif

#if SUPPORT_HARD_LINKS
  if (preserve_hard_links && S_ISREG(file->mode)) {
    write_int(f,(int)file->dev);
    write_int(f,(int)file->inode);
  }
#endif

  if (always_checksum) {
	  write_buf(f,file->sum,csum_length);
  }       

  last_mode = file->mode;
  last_rdev = file->rdev;
  last_uid = file->uid;
  last_gid = file->gid;
  last_time = file->modtime;

  strlcpy(lastname,fname,MAXPATHLEN-1);
  lastname[MAXPATHLEN-1] = 0;
}



static void receive_file_entry(struct file_struct **fptr,
			       unsigned flags,int f)
{
  static time_t last_time;
  static mode_t last_mode;
  static dev_t last_rdev;
  static uid_t last_uid;
  static gid_t last_gid;
  static char lastname[MAXPATHLEN];
  char thisname[MAXPATHLEN];
  int l1=0,l2=0;
  char *p;
  struct file_struct *file;

  if (flags & SAME_NAME)
    l1 = read_byte(f);
  
  if (flags & LONG_NAME)
    l2 = read_int(f);
  else
    l2 = read_byte(f);

  file = (struct file_struct *)malloc(sizeof(*file));
  if (!file) out_of_memory("receive_file_entry");
  memset((char *)file, 0, sizeof(*file));
  (*fptr) = file;

  if (l2 >= MAXPATHLEN-l1) overflow("receive_file_entry");

  strlcpy(thisname,lastname,l1);
  read_sbuf(f,&thisname[l1],l2);
  thisname[l1+l2] = 0;

  strlcpy(lastname,thisname,MAXPATHLEN-1);
  lastname[MAXPATHLEN-1] = 0;

  clean_fname(thisname);

  if (relative_paths && thisname[0] == '/') {
	  /* strip / off absolute paths in destination */
	  memmove(thisname, thisname+1, strlen(thisname));
	  if (!thisname[0]) strcpy(thisname,".");
  }

  if ((p = strrchr(thisname,'/'))) {
	  static char *lastdir;
	  *p = 0;
	  if (lastdir && strcmp(thisname, lastdir)==0) {
		  file->dirname = lastdir;
	  } else {
		  file->dirname = strdup(thisname);
		  lastdir = file->dirname;
	  }
	  file->basename = strdup(p+1);
  } else {
	  file->dirname = NULL;
	  file->basename = strdup(thisname);
  }

  if (!file->basename) out_of_memory("receive_file_entry 1");


  file->flags = flags;
  file->length = read_longint(f);
  file->modtime = (flags & SAME_TIME) ? last_time : (time_t)read_int(f);
  file->mode = (flags & SAME_MODE) ? last_mode : (mode_t)read_int(f);
  if (preserve_uid)
    file->uid = (flags & SAME_UID) ? last_uid : (uid_t)read_int(f);
  if (preserve_gid)
    file->gid = (flags & SAME_GID) ? last_gid : (gid_t)read_int(f);
  if (preserve_devices && IS_DEVICE(file->mode))
    file->rdev = (flags & SAME_RDEV) ? last_rdev : (dev_t)read_int(f);

  if (preserve_links && S_ISLNK(file->mode)) {
    int l = read_int(f);
    file->link = (char *)malloc(l+1);
    if (!file->link) out_of_memory("receive_file_entry 2");
    read_sbuf(f,file->link,l);
  }

#if SUPPORT_HARD_LINKS
  if (preserve_hard_links && S_ISREG(file->mode)) {
    file->dev = read_int(f);
    file->inode = read_int(f);
  }
#endif
  
  if (always_checksum) {
	  file->sum = (char *)malloc(MD4_SUM_LENGTH);
	  if (!file->sum) out_of_memory("md4 sum");
	  read_buf(f,file->sum,csum_length);
  }
  
  last_mode = file->mode;
  last_rdev = file->rdev;
  last_uid = file->uid;
  last_gid = file->gid;
  last_time = file->modtime;
}


/* determine if a file in a different filesstem should be skipped
   when one_file_system is set. We bascally only want to include
   the mount points - but they can be hard to find! */
static int skip_filesystem(char *fname, STRUCT_STAT *st)
{
	STRUCT_STAT st2;
	char *p = strrchr(fname, '/');

	/* skip all but directories */
	if (!S_ISDIR(st->st_mode)) return 1;

	/* if its not a subdirectory then allow */
	if (!p) return 0;

	*p = 0;
	if (link_stat(fname, &st2)) {
		*p = '/';
		return 0;
	}
	*p = '/';
	
	return (st2.st_dev != filesystem_dev);
}

static struct file_struct *make_file(char *fname)
{
	struct file_struct *file;
	STRUCT_STAT st;
	char sum[SUM_LENGTH];
	char *p;
	char cleaned_name[MAXPATHLEN];

	strlcpy(cleaned_name, fname, MAXPATHLEN-1);
	cleaned_name[MAXPATHLEN-1] = 0;
	clean_fname(cleaned_name);
	fname = cleaned_name;

	memset(sum,0,SUM_LENGTH);

	if (link_stat(fname,&st) != 0) {
		io_error = 1;
		rprintf(FERROR,"%s: %s\n",
			fname,strerror(errno));
		return NULL;
	}

	if (S_ISDIR(st.st_mode) && !recurse) {
		rprintf(FINFO,"skipping directory %s\n",fname);
		return NULL;
	}
	
	if (one_file_system && st.st_dev != filesystem_dev) {
		if (skip_filesystem(fname, &st))
			return NULL;
	}
	
	if (!match_file_name(fname,&st))
		return NULL;
	
	if (verbose > 2)
		rprintf(FINFO,"make_file(%s)\n",fname);
	
	file = (struct file_struct *)malloc(sizeof(*file));
	if (!file) out_of_memory("make_file");
	memset((char *)file,0,sizeof(*file));

	if ((p = strrchr(fname,'/'))) {
		static char *lastdir;
		*p = 0;
		if (lastdir && strcmp(fname, lastdir)==0) {
			file->dirname = lastdir;
		} else {
			file->dirname = strdup(fname);
			lastdir = file->dirname;
		}
		file->basename = strdup(p+1);
		*p = '/';
	} else {
		file->dirname = NULL;
		file->basename = strdup(fname);
	}

	file->modtime = st.st_mtime;
	file->length = st.st_size;
	file->mode = st.st_mode;
	file->uid = st.st_uid;
	file->gid = st.st_gid;
	file->dev = st.st_dev;
	file->inode = st.st_ino;
#ifdef HAVE_ST_RDEV
	file->rdev = st.st_rdev;
#endif

#if SUPPORT_LINKS
	if (S_ISLNK(st.st_mode)) {
		int l;
		char lnk[MAXPATHLEN];
		if ((l=readlink(fname,lnk,MAXPATHLEN-1)) == -1) {
			io_error=1;
			rprintf(FERROR,"readlink %s : %s\n",
				fname,strerror(errno));
			return NULL;
		}
		lnk[l] = 0;
		file->link = strdup(lnk);
	}
#endif

	if (always_checksum) {
		file->sum = (char *)malloc(MD4_SUM_LENGTH);
		if (!file->sum) out_of_memory("md4 sum");
		/* drat. we have to provide a null checksum for non-regular
		   files in order to be compatible with earlier versions
		   of rsync */
		if (S_ISREG(st.st_mode)) {
			file_checksum(fname,file->sum,st.st_size);
		} else {
			memset(file->sum, 0, MD4_SUM_LENGTH);
		}
	}       

	if (flist_dir) {
		static char *lastdir;
		if (lastdir && strcmp(lastdir, flist_dir)==0) {
			file->basedir = lastdir;
		} else {
			file->basedir = strdup(flist_dir);
			lastdir = file->basedir;
		}
	} else {
		file->basedir = NULL;
	}

	if (!S_ISDIR(st.st_mode))
		stats.total_size += st.st_size;

	return file;
}



static void send_file_name(int f,struct file_list *flist,char *fname,
			   int recursive, unsigned base_flags)
{
  struct file_struct *file;

  file = make_file(fname);

  if (!file) return;  
  
  if (flist->count >= flist->malloced) {
	  if (flist->malloced < 1000)
		  flist->malloced += 1000;
	  else
		  flist->malloced *= 2;
	  flist->files = (struct file_struct **)realloc(flist->files,
							sizeof(flist->files[0])*
							flist->malloced);
	  if (!flist->files)
		  out_of_memory("send_file_name");
  }

  if (strcmp(file->basename,"")) {
    flist->files[flist->count++] = file;
    send_file_entry(file,f,base_flags);
  }

  if (S_ISDIR(file->mode) && recursive) {
	  struct exclude_struct **last_exclude_list = local_exclude_list;
	  send_directory(f,flist,f_name(file));
	  local_exclude_list = last_exclude_list;
	  return;
  }
}



static void send_directory(int f,struct file_list *flist,char *dir)
{
	DIR *d;
	struct dirent *di;
	char fname[MAXPATHLEN];
	int l;
	char *p;

	d = opendir(dir);
	if (!d) {
		io_error = 1;
		rprintf(FERROR,"opendir(%s): %s\n",
			dir,strerror(errno));
		return;
	}

	strlcpy(fname,dir,MAXPATHLEN-1);
	l = strlen(fname);
	if (fname[l-1] != '/') {
		if (l == MAXPATHLEN-1) {
			io_error = 1;
			rprintf(FERROR,"skipping long-named directory %s\n",fname);
			closedir(d);
			return;
		}
		strlcat(fname,"/", MAXPATHLEN-1);
		l++;
	}
	p = fname + strlen(fname);

	if (cvs_exclude) {
		if (strlen(fname) + strlen(".cvsignore") <= MAXPATHLEN-1) {
			strcpy(p,".cvsignore");
			local_exclude_list = make_exclude_list(fname,NULL,0,0);
		} else {
			io_error = 1;
			rprintf(FINFO,"cannot cvs-exclude in long-named directory %s\n",fname);
		}
	}  
	
	for (di=readdir(d); di; di=readdir(d)) {
		char *dname = d_name(di);
		if (strcmp(dname,".")==0 ||
		    strcmp(dname,"..")==0)
			continue;
		strlcpy(p,dname,MAXPATHLEN-(l+1));
		send_file_name(f,flist,fname,recurse,0);
	}

	closedir(d);
}



struct file_list *send_file_list(int f,int argc,char *argv[])
{
	int i,l;
	STRUCT_STAT st;
	char *p,*dir;
	char lastpath[MAXPATHLEN]="";
	struct file_list *flist;
	int64 start_write;

	if (verbose && recurse && !am_server && f != -1) {
		rprintf(FINFO,"building file list ... ");
		rflush(FINFO);
	}

	start_write = stats.total_written;

	flist = (struct file_list *)malloc(sizeof(flist[0]));
	if (!flist) out_of_memory("send_file_list");

	flist->count=0;
	flist->malloced = 1000;
	flist->files = (struct file_struct **)malloc(sizeof(flist->files[0])*
						     flist->malloced);
	if (!flist->files) out_of_memory("send_file_list");

	if (f != -1) {
		io_start_buffering(f);
	}

	for (i=0;i<argc;i++) {
		char fname2[MAXPATHLEN];
		char *fname = fname2;

		strlcpy(fname,argv[i],MAXPATHLEN-1);

		l = strlen(fname);
		if (l != 1 && fname[l-1] == '/') {
			strlcat(fname,".",MAXPATHLEN-1);
		}

		if (link_stat(fname,&st) != 0) {
			io_error=1;
			rprintf(FERROR,"%s : %s\n",fname,strerror(errno));
			continue;
		}

		if (S_ISDIR(st.st_mode) && !recurse) {
			rprintf(FINFO,"skipping directory %s\n",fname);
			continue;
		}

		dir = NULL;

		if (!relative_paths) {
			p = strrchr(fname,'/');
			if (p) {
				*p = 0;
				if (p == fname) 
					dir = "/";
				else
					dir = fname;      
				fname = p+1;      
			}
		} else if (f != -1 && (p=strrchr(fname,'/'))) {
			/* this ensures we send the intermediate directories,
			   thus getting their permissions right */
			*p = 0;
			if (strcmp(lastpath,fname)) {
				strlcpy(lastpath, fname, sizeof(lastpath)-1);
				*p = '/';
				for (p=fname+1; (p=strchr(p,'/')); p++) {
					int copy_links_saved = copy_links;
					*p = 0;
					copy_links = 0;
					send_file_name(f, flist, fname, 0, 0);
					copy_links = copy_links_saved;
					*p = '/';
				}
			} else {
				*p = '/';
			}
		}
		
		if (!*fname)
			fname = ".";
		
		if (dir && *dir) {
			char *olddir = push_dir(dir, 1);

			if (!olddir) {
				io_error=1;
				rprintf(FERROR,"push_dir %s : %s\n",
					dir,strerror(errno));
				continue;
			}

			flist_dir = dir;
			if (one_file_system)
				set_filesystem(fname);
			send_file_name(f,flist,fname,recurse,FLAG_DELETE);
			flist_dir = NULL;
			if (pop_dir(olddir) != 0) {
				rprintf(FERROR,"pop_dir %s : %s\n",
					dir,strerror(errno));
				exit_cleanup(1);
			}
			continue;
		}
		
		if (one_file_system)
			set_filesystem(fname);
		send_file_name(f,flist,fname,recurse,FLAG_DELETE);
	}

	if (f != -1) {
		send_file_entry(NULL,f,0);
	}

	if (verbose && recurse && !am_server && f != -1)
		rprintf(FINFO,"done\n");
	
	clean_flist(flist);
	
	/* now send the uid/gid list. This was introduced in protocol
           version 15 */
	if (f != -1 && remote_version >= 15) {
		send_uid_list(f);
	}

	/* if protocol version is >= 17 then send the io_error flag */
	if (f != -1 && remote_version >= 17) {
		write_int(f, io_error);
	}

	if (f != -1) {
		io_end_buffering(f);
		stats.flist_size = stats.total_written - start_write;
		stats.num_files = flist->count;
	}

	if (verbose > 2)
		rprintf(FINFO,"send_file_list done\n");

	return flist;
}


struct file_list *recv_file_list(int f)
{
  struct file_list *flist;
  unsigned char flags;
  int64 start_read;

  if (verbose && recurse && !am_server) {
    rprintf(FINFO,"receiving file list ... ");
    rflush(FINFO);
  }

  start_read = stats.total_read;

  flist = (struct file_list *)malloc(sizeof(flist[0]));
  if (!flist)
    goto oom;

  flist->count=0;
  flist->malloced=1000;
  flist->files = (struct file_struct **)malloc(sizeof(flist->files[0])*
					       flist->malloced);
  if (!flist->files)
    goto oom;


  for (flags=read_byte(f); flags; flags=read_byte(f)) {
    int i = flist->count;

    if (i >= flist->malloced) {
	  if (flist->malloced < 1000)
		  flist->malloced += 1000;
	  else
		  flist->malloced *= 2;
	  flist->files =(struct file_struct **)realloc(flist->files,
						       sizeof(flist->files[0])*
						       flist->malloced);
	  if (!flist->files)
		  goto oom;
    }

    receive_file_entry(&flist->files[i],flags,f);

    if (S_ISREG(flist->files[i]->mode))
	    stats.total_size += flist->files[i]->length;

    flist->count++;

    if (verbose > 2)
      rprintf(FINFO,"recv_file_name(%s)\n",f_name(flist->files[i]));
  }


  if (verbose > 2)
    rprintf(FINFO,"received %d names\n",flist->count);

  clean_flist(flist);

  if (verbose && recurse && !am_server) {
    rprintf(FINFO,"done\n");
  }

  /* now recv the uid/gid list. This was introduced in protocol version 15 */
  if (f != -1 && remote_version >= 15) {
	  recv_uid_list(f, flist);
  }

  /* if protocol version is >= 17 then recv the io_error flag */
  if (f != -1 && remote_version >= 17) {
	  io_error |= read_int(f);
  }

  if (verbose > 2)
    rprintf(FINFO,"recv_file_list done\n");

  stats.flist_size = stats.total_read - start_read;
  stats.num_files = flist->count;

  return flist;

oom:
    out_of_memory("recv_file_list");
    return NULL; /* not reached */
}


int file_compare(struct file_struct **f1,struct file_struct **f2)
{
	if (!(*f1)->basename && !(*f2)->basename) return 0;
	if (!(*f1)->basename) return -1;
	if (!(*f2)->basename) return 1;
	if ((*f1)->dirname == (*f2)->dirname)
		return u_strcmp((*f1)->basename, (*f2)->basename);
	return u_strcmp(f_name(*f1),f_name(*f2));
}


int flist_find(struct file_list *flist,struct file_struct *f)
{
	int low=0,high=flist->count-1;

	if (flist->count <= 0) return -1;

	while (low != high) {
		int mid = (low+high)/2;
		int ret = file_compare(&flist->files[flist_up(flist, mid)],&f);
		if (ret == 0) return flist_up(flist, mid);
		if (ret > 0) {
			high=mid;
		} else {
			low=mid+1;
		}
	}

	if (file_compare(&flist->files[flist_up(flist,low)],&f) == 0)
		return flist_up(flist,low);
	return -1;
}


/*
 * free up one file
 */
static void free_file(struct file_struct *file)
{
	if (!file) return;
	if (file->basename) free(file->basename);
	if (file->link) free(file->link);
	if (file->sum) free(file->sum);
	memset((char *)file, 0, sizeof(*file));
}


/*
 * free up all elements in a flist
 */
void flist_free(struct file_list *flist)
{
	int i;
	for (i=1;i<flist->count;i++) {
		free_file(flist->files[i]);
		free(flist->files[i]);
	}	
	memset((char *)flist->files, 0, sizeof(flist->files[0])*flist->count);
	free(flist->files);
	memset((char *)flist, 0, sizeof(*flist));
	free(flist);
}


/*
 * This routine ensures we don't have any duplicate names in our file list.
 * duplicate names can cause corruption because of the pipelining 
 */
void clean_flist(struct file_list *flist)
{
	int i;

	if (!flist || flist->count == 0) 
		return;
  
	qsort(flist->files,flist->count,
	      sizeof(flist->files[0]),
	      (int (*)())file_compare);

	for (i=1;i<flist->count;i++) {
		if (flist->files[i]->basename &&
		    flist->files[i-1]->basename &&
		    strcmp(f_name(flist->files[i]),
			   f_name(flist->files[i-1])) == 0) {
			if (verbose > 1 && !am_server)
				rprintf(FINFO,"removing duplicate name %s from file list %d\n",
					f_name(flist->files[i-1]),i-1);
			free_file(flist->files[i]);
		} 
	}
}


/*
 * return the full filename of a flist entry
 */
char *f_name(struct file_struct *f)
{
	static char names[10][MAXPATHLEN];
	static int n;
	char *p = names[n];

	if (!f || !f->basename) return NULL;

	n = (n+1)%10;

	if (f->dirname) {
		slprintf(p, MAXPATHLEN-1, "%s/%s", f->dirname, f->basename);
	} else {
		strlcpy(p, f->basename, MAXPATHLEN-1);
	}

	return p;
}