/* $OpenBSD: tar.h,v 1.7 2003/06/02 23:32:09 millert Exp $ */ /* $NetBSD: tar.h,v 1.3 1995/03/21 09:07:51 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. * * @(#)tar.h 8.2 (Berkeley) 4/18/94 */ #define _GNU_SOURCE /* For O_NOFOLLOW. */ #include #include #include #include #include #include #include #include #include #include // #define DEBUG /*************************************************** * Most routines extracted from the PAX project (tar.c...) * ***************************************************/ /* * BSD PAX global data structures and constants. */ #define MAXBLK 64512 /* MAX blocksize supported (posix SPEC) */ /* WARNING: increasing MAXBLK past 32256 */ /* will violate posix spec. */ #define MAXBLK_POSIX 32256 /* MAX blocksize supported as per POSIX */ #define BLKMULT 512 /* blocksize must be even mult of 512 bytes */ /* Don't even think of changing this */ #define DEVBLK 8192 /* default read blksize for devices */ #define FILEBLK 10240 /* default read blksize for files */ #define PAXPATHLEN 3072 /* maximium path length for pax. MUST be */ /* * defines and data structures common to all tar formats */ #define CHK_LEN 8 /* length of checksum field */ #define TNMSZ 100 /* size of name field */ #define NULLCNT 2 /* number of null blocks in trailer */ #define CHK_OFFSET 148 /* start of chksum field */ #define BLNKSUM 256L /* sum of checksum field using ' ' */ /* * General Defines */ #define HEX 16 #define OCT 8 #define _PAX_ 1 #define _TFILE_BASE "paxXXXXXXXXXX" /* * General Macros */ #ifndef MIN #define MIN(a,b) (((a)<(b))?(a):(b)) #endif #ifndef MAX #define MAX(a,b) (((a)>(b))?(a):(b)) #endif #define MAJOR(x) major(x) #define MINOR(x) minor(x) #define TODEV(x, y) makedev((x), (y)) /* * Values used in typeflag field in all tar formats * (only REGTYPE, LNKTYPE and SYMTYPE are used in old bsd tar headers) */ #define REGTYPE '0' /* Regular File */ #define AREGTYPE '\0' /* Regular File */ #define LNKTYPE '1' /* Link */ #define SYMTYPE '2' /* Symlink */ #define CHRTYPE '3' /* Character Special File */ #define BLKTYPE '4' /* Block Special File */ #define DIRTYPE '5' /* Directory */ #define FIFOTYPE '6' /* FIFO */ #define CONTTYPE '7' /* high perf file */ /* * GNU tar compatibility; */ #define LONGLINKTYPE 'K' /* Long Symlink */ #define LONGNAMETYPE 'L' /* Long File */ #define EXTHEADERTYPE 'x' /* Extended header */ /* * Pad with a bit mask, much faster than doing a mod but only works on powers * of 2. Macro below is for block of 512 bytes. */ #define TAR_PAD(x) ((512 - ((x) & 511)) & 511) /* * Data Interchange Format - Extended tar header format - POSIX 1003.1-1990 */ #define TPFSZ 155 #define TMAGIC "ustar" /* ustar and a null */ #define TMAGLEN 6 #define TVERSION "00" /* 00 and no null */ #define TVERSLEN 2 typedef struct { char name[TNMSZ]; /* name of entry */ char mode[8]; /* mode */ char uid[8]; /* uid */ char gid[8]; /* gid */ char size[12]; /* size */ char mtime[12]; /* modification time */ char chksum[CHK_LEN]; /* checksum */ char typeflag; /* type of file. */ char linkname[TNMSZ]; /* linked to name */ char magic[TMAGLEN]; /* magic cookie */ char version[TVERSLEN]; /* version */ char uname[32]; /* ascii owner name */ char gname[32]; /* ascii group name */ char devmajor[8]; /* major device number */ char devminor[8]; /* minor device number */ char prefix[TPFSZ]; /* linked to name */ } HD_USTAR; /* * Routines for manipulating headers, trailers: * asc_ul() * tar_trail() * tar_chksm() * ustar_id() */ static unsigned long tar_chksm (char *, int); char *gnu_hack_string; /* GNU ././@LongLink hackery */ char untrusted_namebuf[MAX_PATH_LENGTH]; int use_seek = 1; extern int ignore_quota_error; struct filters { int filters_count; char **filters; int *filters_matches; int matched_filters; }; /* * asc_ul() * convert hex/octal character string into a u_long. We do not have to * check for overflow! (the headers in all supported formats are not large * enough to create an overflow). * NOTE: strings passed to us are NOT TERMINATED. * Return: * unsigned long value */ u_long asc_ul (char *str, int len, int base) { char *stop; u_long tval = 0; stop = str + len; /* * skip over leading blanks and zeros */ while ((str < stop) && ((*str == ' ') || (*str == '0'))) ++str; /* * for each valid digit, shift running value (tval) over to next digit * and add next digit */ if (base == HEX) { while (str < stop) { if ((*str >= '0') && (*str <= '9')) tval = (tval << 4) + (*str++ - '0'); else if ((*str >= 'A') && (*str <= 'F')) tval = (tval << 4) + 10 + (*str++ - 'A'); else if ((*str >= 'a') && (*str <= 'f')) tval = (tval << 4) + 10 + (*str++ - 'a'); else break; } } else { while ((str < stop) && (*str >= '0') && (*str <= '7')) tval = (tval << 3) + (*str++ - '0'); } return (tval); } /* * 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 (char *buf, int in_resync, int *cnt) { register 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); } /* * 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 unsigned long tar_chksm (char *blk, int len) { char *stop; char *pt; unsigned int 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 += (*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 += (*pt++ & 0xff); return chksm; } /* * 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, size_t 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->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); } /* * Routines for reading tar files // Source: http://www.mkssoftware.com/docs/man4/pax.4.asp struct file_header { // PAX header is similar as file_header and can be completely ignored unsigned char[100] name; unsigned char[8] mode; unsigned char[8] uid; // unused unsigned char[8] gid; // unused unsigned char[12] size; // 0 if file is a link unsigned char[12] mtime; unsigned char[8] chksum; unsigned char[1] typeflag; unsigned char[100] linkname; unsigned char[6] magic; //ustar unsigned char[2] version; // 00 unsigned char[32] uname; // unused unsigned char[32] gname; // unused unsigned char[8] devmajor; // unused ? unsigned char[8] devminor; // unused ? unsigned char[155] prefix; // only used for files > 100 characters. could be unused ? }; enum { TYPE_REGULAR, //0 TYPE_ARCHIVE_LINK, //1 TYPE_SYMLINK, //2 TYPE_CHARACTER_DEVICE, //3 TYPE_BLOCK_DEVICE, //4 TYPE_DIRECTORY, //5 TYPE_FIFO, //6 // Other types: TYPE_EXTENDED_USAGE, //xxxxx // A-Z are available for custom usage }; // Extended attribute: // length keyword=value // atime, charset, comment, gname, linkpath, mtime, path, size, uname */ enum { NEED_NOTHING, NEED_SKIP, NEED_SKIP_FILE, // distinguish between skipped file and unwanted blocks (extended headers etc) NEED_READ, NEED_SYNC_TRAIL, INVALID_HEADER, MEMORY_ALLOC_FAILED, }; /* * 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 n_dirs = 0; char ** dirs_headers_sent = NULL; int ustar_rd (int fd, struct file_header * untrusted_hdr, char *buf, struct stat * sb, struct filters *filters) { register HD_USTAR *hd; register char *dest; register int cnt = 0; int ret; int i; int should_extract; /* DISABLED: unused dev_t devmajor; dev_t devminor; */ /* * we only get proper sized buffers */ #ifdef DEBUG fprintf(stderr,"Checking if valid header\n"); #endif if (ustar_id (buf, BLKMULT) < 0) { #ifdef DEBUG fprintf (stderr, "Invalid header\n"); #endif return INVALID_HEADER; } #ifdef DEBUG fprintf(stderr,"Valid header!\n"); #endif /* DISABLED: Internal to PAX arcn->org_name = arcn->name; arcn->sb.st_nlink = 1; arcn->pat = NULL; arcn->nlen = 0; */ untrusted_hdr->namelen = 0; hd = (HD_USTAR *) buf; /* * see if the filename is split into two parts. if, so joint the parts. * we copy the prefix first and add a / between the prefix and name. */ dest = untrusted_namebuf; if (*(hd->prefix) != '\0') { cnt = strlen(strncpy (dest, hd->prefix, MIN(sizeof (untrusted_namebuf) - 1,TPFSZ+1))); dest += cnt; *dest++ = '/'; cnt++; } if (gnu_hack_string) { untrusted_hdr->namelen = cnt + strlen(strncpy (dest, gnu_hack_string, MIN(TNMSZ+1, sizeof (untrusted_namebuf) - cnt))); free(gnu_hack_string); gnu_hack_string = NULL; } else untrusted_hdr->namelen = cnt + strlen(strncpy (dest, hd->name, MIN(TNMSZ+1, sizeof (untrusted_namebuf) - cnt))); // qfile count the \0 in the namelen untrusted_hdr->namelen += 1; #ifdef DEBUG fprintf(stderr,"Retrieved name len: %d\n",untrusted_hdr->namelen); fprintf(stderr,"Retrieved name: %s\n",untrusted_namebuf); #endif /* * follow the spec to the letter. we should only have mode bits, strip * off all other crud we may be passed. */ sb->st_mode = (mode_t) (asc_ul (hd->mode, sizeof (hd->mode), OCT) & 0xfff); untrusted_hdr->mode = sb->st_mode; #if defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64 sb->st_size = (off_t) asc_uqd (hd->size, sizeof (hd->size), OCT); #else sb->st_size = (off_t) asc_ul (hd->size, sizeof (hd->size), OCT); #endif untrusted_hdr->filelen = sb->st_size; untrusted_hdr->atime = (time_t) asc_ul (hd->mtime, sizeof (hd->mtime), OCT); untrusted_hdr->mtime = untrusted_hdr->atime; untrusted_hdr->atime_nsec = untrusted_hdr->mtime_nsec = 0; sb->st_mtime = (time_t) asc_ul (hd->mtime, sizeof (hd->mtime), OCT); sb->st_ctime = sb->st_atime = 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). */ /* DISABLED: unused hd->gname[sizeof (hd->gname) - 1] = '\0'; if (gid_name (hd->gname, &(arcn->sb.st_gid)) < 0) arcn->sb.st_gid = (gid_t) asc_ul (hd->gid, sizeof (hd->gid), OCT); hd->uname[sizeof (hd->uname) - 1] = '\0'; if (uid_name (hd->uname, &(arcn->sb.st_uid)) < 0) 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 */ /* Disabled: pax specific arcn->ln_name[0] = '\0'; arcn->ln_nlen = 0; 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: #ifdef DEBUG fprintf(stderr,"File is FIFOTYPE\n"); #endif /* DISABLED: unused arcn->type = PAX_FIF; arcn->sb.st_mode |= S_IFIFO; */ break; case DIRTYPE: #ifdef DEBUG fprintf(stderr,"File is DIRTYPE\n"); #endif /* DISABLED: unused 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: #ifdef DEBUG fprintf(stderr,"File is BLKTYPE\n"); #endif break; case CHRTYPE: #ifdef DEBUG fprintf(stderr,"File is CHRTYPE\n"); #endif /* * 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; */ } /* DISABLED: unused 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: #ifdef DEBUG fprintf(stderr,"File is SYMTYPE\n"); #endif break; case LNKTYPE: #ifdef DEBUG fprintf(stderr,"File is LNKTYPE\n"); #endif 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; } /* * copy the link name */ // arcn->ln_nlen = strlcpy (arcn->ln_name, hd->linkname, // MIN(TNMSZ+1,sizeof (arcn->ln_name))); break; case LONGLINKTYPE: #ifdef DEBUG fprintf(stderr,"File is LONGLINKTYPE\n"); #endif break; case LONGNAMETYPE: #ifdef DEBUG fprintf(stderr,"File is LONGNAMETYPE\n"); #endif /* * 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; // arcn->ln_name[0] = '\0'; // arcn->ln_nlen = 0; break; case CONTTYPE: #ifdef DEBUG fprintf(stderr,"File is CONTTYPE\n"); #endif break; case AREGTYPE: #ifdef DEBUG fprintf(stderr,"File is AREGTYPE\n"); #endif break; case REGTYPE: #ifdef DEBUG fprintf(stderr,"File is REGTYPE of size %ld\n",sb->st_size); #endif // Check if user want to extract this file should_extract = 1; for (i=0; i < filters->filters_count; i++) { should_extract = 0; #ifdef DEBUG fprintf(stderr, "Comparing with filter %s\n", filters->filters[i]); #endif if (strncmp(untrusted_namebuf, filters->filters[i], strlen(filters->filters[i])) == 0) { #ifdef DEBUG fprintf(stderr, "Match (%d)\n", filters->filters_matches[i]); #endif should_extract = 1; filters->filters_matches[i]++; if (filters->filters_matches[i] == 1) { // first match filters->matched_filters++; } break; } } if (should_extract != 1) { #ifdef DEBUG fprintf(stderr, "File should be filtered.. Skipping\n"); #endif return NEED_SKIP_FILE; } // Create a copy of untrusted_namebuf to be used for strtok char * dirbuf; dirbuf = malloc(sizeof (char) * (untrusted_hdr->namelen)); if (dirbuf == NULL) return MEMORY_ALLOC_FAILED; dirbuf = strncpy(dirbuf, untrusted_namebuf, untrusted_hdr->namelen); int i = 0; int dir_found = 0; size_t pathsize = 0; char * path = NULL; struct file_header dir_header; // Split the path in directories and recompose it incrementally char * last_token = strtok(dirbuf,"/"); char * token = strtok(NULL, "/"); size_t len_last_token = 0; while (token != NULL) { #ifdef DEBUG fprintf(stderr,"Found directory %s (last:%s)\n",token,last_token); #endif // Recompose the path based on last discovered directory len_last_token = strlen(last_token); if (path == NULL) { path = malloc(sizeof (char) * (len_last_token+1)); if (path == NULL) return MEMORY_ALLOC_FAILED; path = memcpy(path, last_token, len_last_token); path[len_last_token] = '\0'; } else { pathsize = strlen(path); path = realloc(path, sizeof (char) * (strlen(path)+1+len_last_token+1)); if (path == NULL) return MEMORY_ALLOC_FAILED; path[pathsize] = '/'; memcpy(path+pathsize+1, last_token, len_last_token); path[pathsize+len_last_token+1] = '\0'; } #ifdef DEBUG fprintf(stderr,"Path is %s\n",path); #endif #ifdef DEBUG fprintf(stderr,"Checking from i=0 i<%d\n",n_dirs); #endif // Verify if qfile headers for the current path have already been sent based on the dirs_headers_sent table dir_found = 0; for (i = 0; i < n_dirs; ++i) { #ifdef DEBUG fprintf(stderr,"Comparing with %d %d %s %s\n",i,n_dirs,dirs_headers_sent[i],path); #endif if (strcmp(dirs_headers_sent[i],path)==0) { #ifdef DEBUG fprintf(stderr,"Directory headers already sent\n"); #endif dir_found=1; } } if (dir_found == 0) { // Register the current path as being sent in the dirs_headers_sent table #ifdef DEBUG fprintf(stderr,"Inserting %s into register\n",path); #endif dirs_headers_sent = realloc(dirs_headers_sent, sizeof (char*) * (++n_dirs)); if (dirs_headers_sent == NULL) return MEMORY_ALLOC_FAILED; dirs_headers_sent[n_dirs-1] = malloc(sizeof (char) * (strlen(path)+1)); if (dirs_headers_sent[n_dirs-1] == NULL) return MEMORY_ALLOC_FAILED; memcpy(dirs_headers_sent[n_dirs-1], path, strlen(path)+1); // Initialize the qfile headers for the current directory path dir_header.namelen = strlen(path)+1; dir_header.atime = untrusted_hdr->atime; dir_header.atime_nsec = untrusted_hdr->atime_nsec; dir_header.mtime = untrusted_hdr->mtime; dir_header.mtime_nsec = untrusted_hdr->mtime_nsec; dir_header.mode = untrusted_hdr->mode | S_IFDIR; dir_header.filelen = 0; #ifdef DEBUG fprintf(stderr,"Sending directory headers for %s\n",path); #endif // Send the qfile headers for the current directory path write_headers(&dir_header, path); } last_token = token; token = strtok(NULL, "/"); } free(path); free(dirbuf); #ifdef DEBUG fprintf(stderr,"End of directory checks\n"); #endif // Restore POSIX stat file mode (because PAX format use its own file type) untrusted_hdr->mode |= S_IFREG; #ifdef DEBUG fprintf(stderr,"Writing file header\n"); #endif // Send header and file content write_headers(untrusted_hdr, untrusted_namebuf); #ifdef DEBUG fprintf(stderr,"Writing file content\n"); #endif ret = copy_file_with_crc(1, fd, untrusted_hdr->filelen); #ifdef DEBUG fprintf(stderr,"Copyfile returned with error %d\n",ret); #endif if (ret != COPY_FILE_OK) { if (ret != COPY_FILE_WRITE_ERROR) gui_fatal("Copying file %s: %s", untrusted_namebuf, copy_file_status_to_str(ret)); else { fprintf(stderr,"UNKNOWN ERROR RETURN STATUS:%d\n.. Waiting...\n",ret); set_block(0); wait_for_result(); exit(1); } } // Extract extra padding #ifdef DEBUG fprintf(stderr,"Need to remove pad:%lld %lld\n",untrusted_hdr->filelen,BLKMULT-(untrusted_hdr->filelen%BLKMULT)); #endif if (untrusted_hdr->filelen%BLKMULT > 0) { if (!read_all(fd, buf, BLKMULT-(untrusted_hdr->filelen%BLKMULT))) { wait_for_result(); exit(1); } } // Resync trailing headers in order to find next file chunck in the tar file return NEED_SYNC_TRAIL; break; case EXTHEADERTYPE: #ifdef DEBUG fprintf(stderr,"Extended HEADER encountered\n"); #endif return NEED_SKIP; break; default: #ifdef DEBUG fprintf(stderr,"Default type detected:%c\n",hd->typeflag); #endif return NEED_SKIP; /* * 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 NEED_SKIP; } void tar_file_processor(int fd, struct filters *filters) { int ret; int i; int current; struct file_header hdr; struct stat sb; /* stat buffer see stat(2) */ char buf[BLKMULT+1]; i=0; current = NEED_READ; size_t to_skip = 0; int sync_count = 0; while (read_all(fd, buf, BLKMULT)) { ret = 0; if (current==NEED_SYNC_TRAIL) { ret = tar_trail (buf, 1, &sync_count); #ifdef DEBUG fprintf(stderr,"Synchronizing trail: %d %d\n", ret, sync_count); #endif if (ret != 1) { current = NEED_READ; sync_count = 0; } } if (current==NEED_READ) { current = ustar_rd(fd, &hdr, buf, &sb, filters); #ifdef DEBUG fprintf(stderr,"Return %d\n", current); #endif } if (current==NEED_SKIP || current==NEED_SKIP_FILE) { if (current==NEED_SKIP_FILE && filters->filters_count > 0 && filters->filters_count == filters->matched_filters) { // This assume that either: // a) files are sorted (using full path as sort key) // b) all the directory content is in // consecutive block and only directories // are given as filters // This is true for backups prepared by qvm-backup #ifdef DEBUG fprintf(stderr, "All filters matched at least once - assuming end of requested data\n"); #endif return; } to_skip = hdr.filelen; #ifdef DEBUG fprintf(stderr,"Need to skip %lld bytes (matched filters %d < %d)\n", hdr.filelen, filters->matched_filters, filters->filters_count); fprintf(stderr,"Need to remove pad:%ld %lld %lld\n",to_skip,hdr.filelen,BLKMULT-(hdr.filelen%BLKMULT)); #endif if (to_skip%BLKMULT > 0) { to_skip += BLKMULT-(to_skip%BLKMULT); } if (use_seek) { int tries = 3; while (lseek(fd, to_skip, SEEK_CUR) < 0) { if (errno == ESPIPE) { // fallback to read() use_seek = 0; break; } else if (errno == EAGAIN) { /* WTF?! lseek theoretically never returns this error, but * in practice it was seen... */ if (tries--) continue; } perror("lseek"); exit(1); } } // not using "else" because above can fallback to read() method if (!use_seek) { while (to_skip > 0) { ret = read_all(fd, &buf, MIN(to_skip,BLKMULT)); if (ret <= 0) { exit(1); } to_skip -= MIN(to_skip,BLKMULT); } } current = NEED_SYNC_TRAIL; } i++; //if (i >= 10) // exit(0); } } int main(int argc, char **argv) { char *entry; int fd = -1; int use_stdin = 1; struct filters filters; qfile_pack_init(); /* when extracting backup header, dom0 will terminate the transfer with * EDQUOT just after getting qubes.xml */ set_ignore_quota_error(1); set_nonblock(0); if (argc > 1) { if (strcmp(argv[1], "-")==0) { use_stdin = 1; } else { use_stdin = 0; entry = argv[1]; #ifdef DEBUG fprintf(stderr, "Parsing file %s\n",entry); #endif fd = open(entry, O_RDONLY); if (fd < 0) { fprintf(stderr,"Error opening file %s\n",entry); exit(2); } } } // Parse tar file if (argc > 2) filters.filters_count = argc-2; else filters.filters_count = 0; filters.filters = argv+2; filters.filters_matches = calloc(filters.filters_count, sizeof(int)); if (filters.filters_matches == NULL) { perror("calloc"); exit(1); } filters.matched_filters = 0; if (use_stdin == 1) { #ifdef DEBUG fprintf(stderr,"Using STDIN\n"); #endif set_block(0); fd = 0; } if (fd < 0) { fprintf(stderr, "No input file provided\n"); exit(1); } tar_file_processor(fd, &filters); notify_end_and_wait_for_result(); return 0; }