/* $OpenBSD: tar.c,v 1.69 2021/06/14 00:36:13 deraadt Exp $ */ /* $NetBSD: tar.c,v 1.5 1995/03/21 09:07:49 cgd Exp $ */ /*- * Copyright (c) 1992 Keith Muller. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Keith Muller of the University of California, San Diego. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #ifndef major #include #endif #include "pax.h" #include "extern.h" #include "tar.h" /* * Routines for reading, writing and header identify of various versions of tar */ static size_t expandname(char *, size_t, char **, const char *, size_t); static u_long tar_chksm(char *, int); static char *name_split(char *, int); static int ul_oct(u_long, char *, int, int); static int ull_oct(unsigned long long, char *, int, int); #ifndef SMALL static int rd_xheader(ARCHD *arcn, int, off_t); #endif static uid_t uid_nobody; static uid_t uid_warn; static gid_t gid_nobody; static gid_t gid_warn; /* * Routines common to all versions of tar */ int tar_nodir; /* do not write dirs under old tar */ char *gnu_name_string; /* GNU ././@LongLink hackery name */ char *gnu_link_string; /* GNU ././@LongLink hackery link */ /* * tar_endwr() * add the tar trailer of two null blocks * Return: * 0 if ok, -1 otherwise (what wr_skip returns) */ int tar_endwr(void) { return wr_skip(NULLCNT * BLKMULT); } /* * tar_endrd() * no cleanup needed here, just return size of trailer (for append) * Return: * size of trailer (2 * BLKMULT) */ off_t tar_endrd(void) { return NULLCNT * BLKMULT; } /* * tar_trail() * Called to determine if a header block is a valid trailer. We are passed * the block, the in_sync flag (which tells us we are in resync mode; * looking for a valid header), and cnt (which starts at zero) which is * used to count the number of empty blocks we have seen so far. * Return: * 0 if a valid trailer, -1 if not a valid trailer, or 1 if the block * could never contain a header. */ int tar_trail(ARCHD *ignore, char *buf, int in_resync, int *cnt) { int i; /* * look for all zero, trailer is two consecutive blocks of zero */ for (i = 0; i < BLKMULT; ++i) { if (buf[i] != '\0') break; } /* * if not all zero it is not a trailer, but MIGHT be a header. */ if (i != BLKMULT) return(-1); /* * When given a zero block, we must be careful! * If we are not in resync mode, check for the trailer. Have to watch * out that we do not mis-identify file data as the trailer, so we do * NOT try to id a trailer during resync mode. During resync mode we * might as well throw this block out since a valid header can NEVER be * a block of all 0 (we must have a valid file name). */ if (!in_resync && (++*cnt >= NULLCNT)) return(0); return(1); } /* * ul_oct() * convert an unsigned long to an octal string. many oddball field * termination characters are used by the various versions of tar in the * different fields. term selects which kind to use. str is '0' padded * at the front to len. we are unable to use only one format as many old * tar readers are very cranky about this. * Return: * 0 if the number fit into the string, -1 otherwise */ static int ul_oct(u_long val, char *str, int len, int term) { char *pt; /* * term selects the appropriate character(s) for the end of the string */ pt = str + len - 1; switch (term) { case 3: *pt-- = '\0'; break; case 2: *pt-- = ' '; *pt-- = '\0'; break; case 1: *pt-- = ' '; break; case 0: default: *pt-- = '\0'; *pt-- = ' '; break; } /* * convert and blank pad if there is space */ while (pt >= str) { *pt-- = '0' + (char)(val & 0x7); val >>= 3; if (val == 0) break; } while (pt >= str) *pt-- = '0'; if (val != 0) return(-1); return(0); } /* * ull_oct() * Convert an unsigned long long to an octal string. One of many oddball * field termination characters are used by the various versions of tar * in the different fields. term selects which kind to use. str is * '0' padded at the front to len. We are unable to use only one format * as many old tar readers are very cranky about this. * Return: * 0 if the number fit into the string, -1 otherwise */ static int ull_oct(unsigned long long val, char *str, int len, int term) { char *pt; /* * term selects the appropriate character(s) for the end of the string */ pt = str + len - 1; switch (term) { case 3: *pt-- = '\0'; break; case 2: *pt-- = ' '; *pt-- = '\0'; break; case 1: *pt-- = ' '; break; case 0: default: *pt-- = '\0'; *pt-- = ' '; break; } /* * convert and blank pad if there is space */ while (pt >= str) { *pt-- = '0' + (char)(val & 0x7); val >>= 3; if (val == 0) break; } while (pt >= str) *pt-- = '0'; if (val != 0) return(-1); return(0); } /* * tar_chksm() * calculate the checksum for a tar block counting the checksum field as * all blanks (BLNKSUM is that value pre-calculated, the sum of 8 blanks). * NOTE: we use len to short circuit summing 0's on write since we ALWAYS * pad headers with 0. * Return: * unsigned long checksum */ static u_long tar_chksm(char *blk, int len) { char *stop; char *pt; u_long chksm = BLNKSUM; /* initial value is checksum field sum */ /* * add the part of the block before the checksum field */ pt = blk; stop = blk + CHK_OFFSET; while (pt < stop) chksm += (u_long)(*pt++ & 0xff); /* * move past the checksum field and keep going, spec counts the * checksum field as the sum of 8 blanks (which is pre-computed as * BLNKSUM). * ASSUMED: len is greater than CHK_OFFSET. (len is where our 0 padding * starts, no point in summing zero's) */ pt += CHK_LEN; stop = blk + len; while (pt < stop) chksm += (u_long)(*pt++ & 0xff); return(chksm); } /* * Routines for old BSD style tar (also made portable to sysV tar) */ /* * tar_id() * determine if a block given to us is a valid tar header (and not a USTAR * header). We have to be on the lookout for those pesky blocks of all * zero's. * Return: * 0 if a tar header, -1 otherwise */ int tar_id(char *blk, int size) { HD_TAR *hd; HD_USTAR *uhd; if (size < BLKMULT) return(-1); hd = (HD_TAR *)blk; uhd = (HD_USTAR *)blk; /* * check for block of zero's first, a simple and fast test, then make * sure this is not a ustar header by looking for the ustar magic * cookie. We should use TMAGLEN, but some USTAR archive programs are * wrong and create archives missing the \0. Last we check the * checksum. If this is ok we have to assume it is a valid header. */ if (hd->name[0] == '\0') return(-1); if (strncmp(uhd->magic, TMAGIC, TMAGLEN - 1) == 0) return(-1); if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT)) return(-1); force_one_volume = 1; return(0); } /* * tar_opt() * handle tar format specific -o options * Return: * 0 if ok -1 otherwise */ int tar_opt(void) { OPLIST *opt; while ((opt = opt_next()) != NULL) { if (strcmp(opt->name, TAR_OPTION) || strcmp(opt->value, TAR_NODIR)) { paxwarn(1, "Unknown tar format -o option/value pair %s=%s", opt->name, opt->value); paxwarn(1,"%s=%s is the only supported tar format option", TAR_OPTION, TAR_NODIR); return(-1); } /* * we only support one option, and only when writing */ if ((act != APPND) && (act != ARCHIVE)) { paxwarn(1, "%s=%s is only supported when writing.", opt->name, opt->value); return(-1); } tar_nodir = 1; } return(0); } /* * tar_rd() * extract the values out of block already determined to be a tar header. * store the values in the ARCHD parameter. * Return: * 0 */ int tar_rd(ARCHD *arcn, char *buf) { HD_TAR *hd; unsigned long long val; char *pt; /* * we only get proper sized buffers passed to us */ if (tar_id(buf, BLKMULT) < 0) return(-1); memset(arcn, 0, sizeof(*arcn)); arcn->org_name = arcn->name; arcn->sb.st_nlink = 1; /* * copy out the name and values in the stat buffer */ hd = (HD_TAR *)buf; if (hd->linkflag != LONGLINKTYPE && hd->linkflag != LONGNAMETYPE) { arcn->nlen = expandname(arcn->name, sizeof(arcn->name), &gnu_name_string, hd->name, sizeof(hd->name)); arcn->ln_nlen = expandname(arcn->ln_name, sizeof(arcn->ln_name), &gnu_link_string, hd->linkname, sizeof(hd->linkname)); } arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode,sizeof(hd->mode),OCT) & 0xfff); arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT); arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT); arcn->sb.st_size = (off_t)asc_ull(hd->size, sizeof(hd->size), OCT); val = asc_ull(hd->mtime, sizeof(hd->mtime), OCT); if (val > MAX_TIME_T) arcn->sb.st_mtime = INT_MAX; /* XXX 2038 */ else arcn->sb.st_mtime = val; arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime; /* * have to look at the last character, it may be a '/' and that is used * to encode this as a directory */ pt = &(arcn->name[arcn->nlen - 1]); arcn->pad = 0; arcn->skip = 0; switch (hd->linkflag) { case SYMTYPE: /* * symbolic link, need to get the link name and set the type in * the st_mode so -v printing will look correct. */ arcn->type = PAX_SLK; arcn->sb.st_mode |= S_IFLNK; break; case LNKTYPE: /* * hard link, need to get the link name, set the type in the * st_mode and st_nlink so -v printing will look better. */ arcn->type = PAX_HLK; arcn->sb.st_nlink = 2; /* * no idea of what type this thing really points at, but * we set something for printing only. */ arcn->sb.st_mode |= S_IFREG; break; case LONGLINKTYPE: case LONGNAMETYPE: /* * GNU long link/file; we tag these here and let the * pax internals deal with it -- too ugly otherwise. */ arcn->type = hd->linkflag == LONGLINKTYPE ? PAX_GLL : PAX_GLF; arcn->pad = TAR_PAD(arcn->sb.st_size); arcn->skip = arcn->sb.st_size; break; case DIRTYPE: /* * It is a directory, set the mode for -v printing */ arcn->type = PAX_DIR; arcn->sb.st_mode |= S_IFDIR; arcn->sb.st_nlink = 2; break; case AREGTYPE: case REGTYPE: default: /* * If we have a trailing / this is a directory and NOT a file. */ arcn->ln_name[0] = '\0'; arcn->ln_nlen = 0; if (*pt == '/') { /* * it is a directory, set the mode for -v printing */ arcn->type = PAX_DIR; arcn->sb.st_mode |= S_IFDIR; arcn->sb.st_nlink = 2; } else { /* * have a file that will be followed by data. Set the * skip value to the size field and calculate the size * of the padding. */ arcn->type = PAX_REG; arcn->sb.st_mode |= S_IFREG; arcn->pad = TAR_PAD(arcn->sb.st_size); arcn->skip = arcn->sb.st_size; } break; } /* * strip off any trailing slash. */ if (*pt == '/') { *pt = '\0'; --arcn->nlen; } return(0); } /* * tar_wr() * write a tar header for the file specified in the ARCHD to the archive. * Have to check for file types that cannot be stored and file names that * are too long. Be careful of the term (last arg) to ul_oct, each field * of tar has it own spec for the termination character(s). * ASSUMED: space after header in header block is zero filled * Return: * 0 if file has data to be written after the header, 1 if file has NO * data to write after the header, -1 if archive write failed */ int tar_wr(ARCHD *arcn) { HD_TAR *hd; int len; char hdblk[sizeof(HD_TAR)]; /* * check for those file system types which tar cannot store */ switch (arcn->type) { case PAX_DIR: /* * user asked that dirs not be written to the archive */ if (tar_nodir) return(1); break; case PAX_CHR: paxwarn(1, "Tar cannot archive a character device %s", arcn->org_name); return(1); case PAX_BLK: paxwarn(1, "Tar cannot archive a block device %s", arcn->org_name); return(1); case PAX_SCK: paxwarn(1, "Tar cannot archive a socket %s", arcn->org_name); return(1); case PAX_FIF: paxwarn(1, "Tar cannot archive a fifo %s", arcn->org_name); return(1); case PAX_SLK: case PAX_HLK: case PAX_HRG: if ((size_t)arcn->ln_nlen > sizeof(hd->linkname)) { paxwarn(1, "Link name too long for tar %s", arcn->ln_name); return(1); } break; case PAX_REG: case PAX_CTG: default: break; } /* * check file name len, remember extra char for dirs (the / at the end) */ len = arcn->nlen; if (arcn->type == PAX_DIR) ++len; if ((size_t)len > sizeof(hd->name)) { paxwarn(1, "File name too long for tar %s", arcn->name); return(1); } /* * Copy the data out of the ARCHD into the tar header based on the type * of the file. Remember, many tar readers want all fields to be * padded with zero so we zero the header first. We then set the * linkflag field (type), the linkname, the size, and set the padding * (if any) to be added after the file data (0 for all other types, * as they only have a header). */ memset(hdblk, 0, sizeof(hdblk)); hd = (HD_TAR *)hdblk; fieldcpy(hd->name, sizeof(hd->name), arcn->name, sizeof(arcn->name)); arcn->pad = 0; if (arcn->type == PAX_DIR) { /* * directories are the same as files, except have a filename * that ends with a /, we add the slash here. No data follows * dirs, so no pad. */ hd->linkflag = AREGTYPE; hd->name[len-1] = '/'; if (ul_oct(0, hd->size, sizeof(hd->size), 1)) goto out; } else if (arcn->type == PAX_SLK) { /* * no data follows this file, so no pad */ hd->linkflag = SYMTYPE; fieldcpy(hd->linkname, sizeof(hd->linkname), arcn->ln_name, sizeof(arcn->ln_name)); if (ul_oct(0, hd->size, sizeof(hd->size), 1)) goto out; } else if (PAX_IS_HARDLINK(arcn->type)) { /* * no data follows this file, so no pad */ hd->linkflag = LNKTYPE; fieldcpy(hd->linkname, sizeof(hd->linkname), arcn->ln_name, sizeof(arcn->ln_name)); if (ul_oct(0, hd->size, sizeof(hd->size), 1)) goto out; } else { /* * data follows this file, so set the pad */ hd->linkflag = AREGTYPE; if (ull_oct(arcn->sb.st_size, hd->size, sizeof(hd->size), 1)) { paxwarn(1, "File is too large for tar %s", arcn->org_name); return(1); } arcn->pad = TAR_PAD(arcn->sb.st_size); } /* * copy those fields that are independent of the type */ if (ul_oct(arcn->sb.st_mode, hd->mode, sizeof(hd->mode), 0) || ull_oct(arcn->sb.st_mtime < 0 ? 0 : arcn->sb.st_mtime, hd->mtime, sizeof(hd->mtime), 1) || ul_oct(arcn->sb.st_uid, hd->uid, sizeof(hd->uid), 0) || ul_oct(arcn->sb.st_gid, hd->gid, sizeof(hd->gid), 0)) goto out; /* * calculate and add the checksum, then write the header. A return of * 0 tells the caller to now write the file data, 1 says no data needs * to be written */ if (ul_oct(tar_chksm(hdblk, sizeof(HD_TAR)), hd->chksum, sizeof(hd->chksum), 3)) goto out; if (wr_rdbuf(hdblk, sizeof(HD_TAR)) < 0) return(-1); if (wr_skip(BLKMULT - sizeof(HD_TAR)) < 0) return(-1); if (PAX_IS_REG(arcn->type)) return(0); return(1); out: /* * header field is out of range */ paxwarn(1, "Tar header field is too small for %s", arcn->org_name); return(1); } /* * Routines for POSIX ustar */ /* * ustar_id() * determine if a block given to us is a valid ustar header. We have to * be on the lookout for those pesky blocks of all zero's * Return: * 0 if a ustar header, -1 otherwise */ int ustar_id(char *blk, int size) { HD_USTAR *hd; if (size < BLKMULT) return(-1); hd = (HD_USTAR *)blk; /* * check for block of zero's first, a simple and fast test then check * ustar magic cookie. We should use TMAGLEN, but some USTAR archive * programs are fouled up and create archives missing the \0. Last we * check the checksum. If ok we have to assume it is a valid header. */ if (hd->prefix[0] == '\0' && hd->name[0] == '\0') return(-1); if (strncmp(hd->magic, TMAGIC, TMAGLEN - 1) != 0) return(-1); if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT)) return(-1); return(0); } /* * ustar_rd() * extract the values out of block already determined to be a ustar header. * store the values in the ARCHD parameter. * Return: * 0 */ int ustar_rd(ARCHD *arcn, char *buf) { HD_USTAR *hd = (HD_USTAR *)buf; char *dest; int cnt = 0; dev_t devmajor; dev_t devminor; unsigned long long val; /* * we only get proper sized buffers */ if (ustar_id(buf, BLKMULT) < 0) return(-1); #ifndef SMALL reset: #endif memset(arcn, 0, sizeof(*arcn)); arcn->org_name = arcn->name; arcn->sb.st_nlink = 1; #ifndef SMALL /* Process Extended headers. */ if (hd->typeflag == XHDRTYPE || hd->typeflag == GHDRTYPE) { if (rd_xheader(arcn, hd->typeflag == GHDRTYPE, (off_t)asc_ull(hd->size, sizeof(hd->size), OCT)) < 0) return (-1); /* Update and check the ustar header. */ if (rd_wrbuf(buf, BLKMULT) != BLKMULT) return (-1); if (ustar_id(buf, BLKMULT) < 0) return(-1); /* if the next block is another extension, reset the values */ if (hd->typeflag == XHDRTYPE || hd->typeflag == GHDRTYPE) goto reset; } #endif if (!arcn->nlen) { /* * See if the filename is split into two parts. if, so join * the parts. We copy the prefix first and add a / between * the prefix and name. */ dest = arcn->name; if (*(hd->prefix) != '\0') { cnt = fieldcpy(dest, sizeof(arcn->name) - 1, hd->prefix, sizeof(hd->prefix)); dest += cnt; *dest++ = '/'; cnt++; } else cnt = 0; if (hd->typeflag != LONGLINKTYPE && hd->typeflag != LONGNAMETYPE) { arcn->nlen = cnt + expandname(dest, sizeof(arcn->name) - cnt, &gnu_name_string, hd->name, sizeof(hd->name)); } } if (!arcn->ln_nlen && hd->typeflag != LONGLINKTYPE && hd->typeflag != LONGNAMETYPE) { arcn->ln_nlen = expandname(arcn->ln_name, sizeof(arcn->ln_name), &gnu_link_string, hd->linkname, sizeof(hd->linkname)); } /* * follow the spec to the letter. we should only have mode bits, strip * off all other crud we may be passed. */ arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode, sizeof(hd->mode), OCT) & 0xfff); arcn->sb.st_size = (off_t)asc_ull(hd->size, sizeof(hd->size), OCT); val = asc_ull(hd->mtime, sizeof(hd->mtime), OCT); if (val > MAX_TIME_T) arcn->sb.st_mtime = INT_MAX; /* XXX 2038 */ else arcn->sb.st_mtime = val; arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime; /* * If we can find the ascii names for gname and uname in the password * and group files we will use the uid's and gid they bind. Otherwise * we use the uid and gid values stored in the header. (This is what * the posix spec wants). */ hd->gname[sizeof(hd->gname) - 1] = '\0'; if (Nflag || gid_from_group(hd->gname, &(arcn->sb.st_gid)) == -1) arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT); hd->uname[sizeof(hd->uname) - 1] = '\0'; if (Nflag || uid_from_user(hd->uname, &(arcn->sb.st_uid)) == -1) arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT); /* * set the defaults, these may be changed depending on the file type */ arcn->pad = 0; arcn->skip = 0; arcn->sb.st_rdev = (dev_t)0; /* * set the mode and PAX type according to the typeflag in the header */ switch (hd->typeflag) { case FIFOTYPE: arcn->type = PAX_FIF; arcn->sb.st_mode |= S_IFIFO; break; case DIRTYPE: arcn->type = PAX_DIR; arcn->sb.st_mode |= S_IFDIR; arcn->sb.st_nlink = 2; /* * Some programs that create ustar archives append a '/' * to the pathname for directories. This clearly violates * ustar specs, but we will silently strip it off anyway. */ if (arcn->name[arcn->nlen - 1] == '/') arcn->name[--arcn->nlen] = '\0'; break; case BLKTYPE: case CHRTYPE: /* * this type requires the rdev field to be set. */ if (hd->typeflag == BLKTYPE) { arcn->type = PAX_BLK; arcn->sb.st_mode |= S_IFBLK; } else { arcn->type = PAX_CHR; arcn->sb.st_mode |= S_IFCHR; } devmajor = (dev_t)asc_ul(hd->devmajor,sizeof(hd->devmajor),OCT); devminor = (dev_t)asc_ul(hd->devminor,sizeof(hd->devminor),OCT); arcn->sb.st_rdev = TODEV(devmajor, devminor); break; case SYMTYPE: case LNKTYPE: if (hd->typeflag == SYMTYPE) { arcn->type = PAX_SLK; arcn->sb.st_mode |= S_IFLNK; } else { arcn->type = PAX_HLK; /* * so printing looks better */ arcn->sb.st_mode |= S_IFREG; arcn->sb.st_nlink = 2; } break; case LONGLINKTYPE: case LONGNAMETYPE: /* * GNU long link/file; we tag these here and let the * pax internals deal with it -- too ugly otherwise. */ arcn->type = hd->typeflag == LONGLINKTYPE ? PAX_GLL : PAX_GLF; arcn->pad = TAR_PAD(arcn->sb.st_size); arcn->skip = arcn->sb.st_size; break; case CONTTYPE: case AREGTYPE: case REGTYPE: default: /* * these types have file data that follows. Set the skip and * pad fields. */ arcn->type = PAX_REG; arcn->pad = TAR_PAD(arcn->sb.st_size); arcn->skip = arcn->sb.st_size; arcn->sb.st_mode |= S_IFREG; break; } return(0); } /* * ustar_wr() * write a ustar header for the file specified in the ARCHD to the archive * Have to check for file types that cannot be stored and file names that * are too long. Be careful of the term (last arg) to ul_oct, we only use * '\0' for the termination character (this is different than picky tar) * ASSUMED: space after header in header block is zero filled * Return: * 0 if file has data to be written after the header, 1 if file has NO * data to write after the header, -1 if archive write failed */ int ustar_wr(ARCHD *arcn) { HD_USTAR *hd; const char *name; char *pt, hdblk[sizeof(HD_USTAR)]; /* * check for those file system types ustar cannot store */ if (arcn->type == PAX_SCK) { paxwarn(1, "Ustar cannot archive a socket %s", arcn->org_name); return(1); } /* * user asked that dirs not be written to the archive */ if (arcn->type == PAX_DIR && tar_nodir) return (1); /* * check the length of the linkname */ if (PAX_IS_LINK(arcn->type) && ((size_t)arcn->ln_nlen > sizeof(hd->linkname))) { paxwarn(1, "Link name too long for ustar %s", arcn->ln_name); return(1); } /* * split the path name into prefix and name fields (if needed). if * pt != arcn->name, the name has to be split */ if ((pt = name_split(arcn->name, arcn->nlen)) == NULL) { paxwarn(1, "File name too long for ustar %s", arcn->name); return(1); } /* * zero out the header so we don't have to worry about zero fill below */ memset(hdblk, 0, sizeof(hdblk)); hd = (HD_USTAR *)hdblk; arcn->pad = 0; /* * split the name, or zero out the prefix */ if (pt != arcn->name) { /* * name was split, pt points at the / where the split is to * occur, we remove the / and copy the first part to the prefix */ *pt = '\0'; fieldcpy(hd->prefix, sizeof(hd->prefix), arcn->name, sizeof(arcn->name)); *pt++ = '/'; } /* * copy the name part. this may be the whole path or the part after * the prefix */ fieldcpy(hd->name, sizeof(hd->name), pt, sizeof(arcn->name) - (pt - arcn->name)); /* * set the fields in the header that are type dependent */ switch (arcn->type) { case PAX_DIR: hd->typeflag = DIRTYPE; if (ul_oct(0, hd->size, sizeof(hd->size), 3)) goto out; break; case PAX_CHR: case PAX_BLK: if (arcn->type == PAX_CHR) hd->typeflag = CHRTYPE; else hd->typeflag = BLKTYPE; if (ul_oct(MAJOR(arcn->sb.st_rdev), hd->devmajor, sizeof(hd->devmajor), 3) || ul_oct(MINOR(arcn->sb.st_rdev), hd->devminor, sizeof(hd->devminor), 3) || ul_oct(0, hd->size, sizeof(hd->size), 3)) goto out; break; case PAX_FIF: hd->typeflag = FIFOTYPE; if (ul_oct(0, hd->size, sizeof(hd->size), 3)) goto out; break; case PAX_SLK: case PAX_HLK: case PAX_HRG: if (arcn->type == PAX_SLK) hd->typeflag = SYMTYPE; else hd->typeflag = LNKTYPE; fieldcpy(hd->linkname, sizeof(hd->linkname), arcn->ln_name, sizeof(arcn->ln_name)); if (ul_oct(0, hd->size, sizeof(hd->size), 3)) goto out; break; case PAX_REG: case PAX_CTG: default: /* * file data with this type, set the padding */ if (arcn->type == PAX_CTG) hd->typeflag = CONTTYPE; else hd->typeflag = REGTYPE; arcn->pad = TAR_PAD(arcn->sb.st_size); if (ull_oct(arcn->sb.st_size, hd->size, sizeof(hd->size), 3)) { paxwarn(1, "File is too long for ustar %s", arcn->org_name); return(1); } break; } memcpy(hd->magic, TMAGIC, TMAGLEN); memcpy(hd->version, TVERSION, TVERSLEN); /* * set the remaining fields. Some versions want all 16 bits of mode * we better humor them (they really do not meet spec though).... */ if (ul_oct(arcn->sb.st_uid, hd->uid, sizeof(hd->uid), 3)) { if (uid_nobody == 0) { if (uid_from_user("nobody", &uid_nobody) == -1) goto out; } if (uid_warn != arcn->sb.st_uid) { uid_warn = arcn->sb.st_uid; paxwarn(1, "Ustar header field is too small for uid %lu, " "using nobody", (u_long)arcn->sb.st_uid); } if (ul_oct(uid_nobody, hd->uid, sizeof(hd->uid), 3)) goto out; } if (ul_oct(arcn->sb.st_gid, hd->gid, sizeof(hd->gid), 3)) { if (gid_nobody == 0) { if (gid_from_group("nobody", &gid_nobody) == -1) goto out; } if (gid_warn != arcn->sb.st_gid) { gid_warn = arcn->sb.st_gid; paxwarn(1, "Ustar header field is too small for gid %lu, " "using nobody", (u_long)arcn->sb.st_gid); } if (ul_oct(gid_nobody, hd->gid, sizeof(hd->gid), 3)) goto out; } if (ull_oct(arcn->sb.st_mtime < 0 ? 0 : arcn->sb.st_mtime, hd->mtime, sizeof(hd->mtime), 3) || ul_oct(arcn->sb.st_mode, hd->mode, sizeof(hd->mode), 3)) goto out; if (!Nflag) { if ((name = user_from_uid(arcn->sb.st_uid, 1)) != NULL) strncpy(hd->uname, name, sizeof(hd->uname)); if ((name = group_from_gid(arcn->sb.st_gid, 1)) != NULL) strncpy(hd->gname, name, sizeof(hd->gname)); } /* * calculate and store the checksum write the header to the archive * return 0 tells the caller to now write the file data, 1 says no data * needs to be written */ if (ul_oct(tar_chksm(hdblk, sizeof(HD_USTAR)), hd->chksum, sizeof(hd->chksum), 3)) goto out; if (wr_rdbuf(hdblk, sizeof(HD_USTAR)) < 0) return(-1); if (wr_skip(BLKMULT - sizeof(HD_USTAR)) < 0) return(-1); if (PAX_IS_REG(arcn->type)) return(0); return(1); out: /* * header field is out of range */ paxwarn(1, "Ustar header field is too small for %s", arcn->org_name); return(1); } /* * name_split() * see if the name has to be split for storage in a ustar header. We try * to fit the entire name in the name field without splitting if we can. * The split point is always at a / * Return * character pointer to split point (always the / that is to be removed * if the split is not needed, the points is set to the start of the file * name (it would violate the spec to split there). A NULL is returned if * the file name is too long */ static char * name_split(char *name, int len) { char *start; /* * check to see if the file name is small enough to fit in the name * field. if so just return a pointer to the name. * The strings can fill the complete name and prefix fields * without a NUL terminator. */ if (len <= TNMSZ) return(name); if (len > (TPFSZ + TNMSZ + 1)) return(NULL); /* * we start looking at the biggest sized piece that fits in the name * field. We walk forward looking for a slash to split at. The idea is * to find the biggest piece to fit in the name field (or the smallest * prefix we can find) (the -1 is correct the biggest piece would * include the slash between the two parts that gets thrown away) */ start = name + len - TNMSZ - 1; /* * the prefix may not be empty, so skip the first character when * trying to split a path of exactly TNMSZ+1 characters. * NOTE: This means the ustar format can't store /str if * str contains no slashes and the length of str == TNMSZ */ if (start == name) ++start; while ((*start != '\0') && (*start != '/')) ++start; /* * if we hit the end of the string, this name cannot be split, so we * cannot store this file. */ if (*start == '\0') return(NULL); /* * the split point isn't valid if it results in a prefix * longer than TPFSZ */ if ((start - name) > TPFSZ) return(NULL); /* * ok have a split point, return it to the caller */ return(start); } static size_t expandname(char *buf, size_t len, char **gnu_name, const char *name, size_t limit) { size_t nlen; if (*gnu_name) { /* *gnu_name is NUL terminated */ if ((nlen = strlcpy(buf, *gnu_name, len)) >= len) nlen = len - 1; free(*gnu_name); *gnu_name = NULL; } else nlen = fieldcpy(buf, len, name, limit); return(nlen); } #ifndef SMALL /* shortest possible extended record: "5 a=\n" */ #define MINXHDRSZ 5 /* longest record we'll accept */ #define MAXXHDRSZ BLKMULT static int rd_xheader(ARCHD *arcn, int global, off_t size) { char buf[MAXXHDRSZ]; long len; char *delim, *keyword; char *nextp, *p, *end; int pad, ret = 0; /* before we alter size, make note of how much we have to skip */ pad = TAR_PAD((unsigned)size); p = end = buf; while (size > 0 || p < end) { if (size > 0) { int rdlen; /* shift stuff down */ if (p > buf) { memmove(buf, p, end - p); end -= p - buf; p = buf; } /* fill starting at end */ rdlen = MINIMUM(size, (buf + sizeof buf) - end); if (rd_wrbuf(end, rdlen) != rdlen) { ret = -1; break; } size -= rdlen; end += rdlen; } /* [p, end) is good */ if (memchr(p, ' ', end - p) == NULL || !isdigit((unsigned char)*p)) { paxwarn(1, "Invalid extended header record"); ret = -1; break; } errno = 0; len = strtol(p, &delim, 10); if (*delim != ' ' || (errno == ERANGE && len == LONG_MAX) || len < MINXHDRSZ) { paxwarn(1, "Invalid extended header record length"); ret = -1; break; } if (len > end - p) { paxwarn(1, "Extended header record length %lu is " "out of range", len); /* if we can just toss this record, do so */ len -= end - p; if (len <= size && rd_skip(len) == 0) { size -= len; p = end = buf; continue; } ret = -1; break; } nextp = p + len; keyword = p = delim + 1; p = memchr(p, '=', len); if (!p || nextp[-1] != '\n') { paxwarn(1, "Malformed extended header record"); ret = -1; break; } *p++ = nextp[-1] = '\0'; if (!global) { if (!strcmp(keyword, "path")) { arcn->nlen = strlcpy(arcn->name, p, sizeof(arcn->name)); } else if (!strcmp(keyword, "linkpath")) { arcn->ln_nlen = strlcpy(arcn->ln_name, p, sizeof(arcn->ln_name)); } } p = nextp; } if (rd_skip(size + pad) < 0) return (-1); return (ret); } #endif