diff options
| -rw-r--r-- | src/file_tar.c | 89 | ||||
| -rw-r--r-- | src/file_tar.h | 27 | ||||
| -rw-r--r-- | src/phbs.c | 2 | ||||
| -rw-r--r-- | src/photorec_check_header.h | 2 | ||||
| -rw-r--r-- | src/qphbs.cpp | 2 |
5 files changed, 93 insertions, 29 deletions
diff --git a/src/file_tar.c b/src/file_tar.c index 1056584..bfea497 100644 --- a/src/file_tar.c +++ b/src/file_tar.c @@ -34,6 +34,8 @@ #include "file_tar.h" static void register_header_check_tar(file_stat_t *file_stat); +static const unsigned char tar_header_gnu[6] = { 'u','s','t','a','r',0x00}; +static const unsigned char tar_header_posix[8] = { 'u','s','t','a','r',' ',' ',0x00}; const file_hint_t file_hint_tar= { .extension="tar", @@ -44,26 +46,63 @@ const file_hint_t file_hint_tar= { .register_header_check=®ister_header_check_tar }; -struct posix_header -{ /* byte offset */ - char name[100]; /* 0 */ - char mode[8]; /* 100 */ - char uid[8]; /* 108 */ - char gid[8]; /* 116 */ - char size[12]; /* 124 */ - char mtime[12]; /* 136 */ - char chksum[8]; /* 148 */ - char typeflag; /* 156 */ - char linkname[100]; /* 157 */ - char magic[6]; /* 257 */ - char version[2]; /* 263 */ - char uname[32]; /* 265 */ - char gname[32]; /* 297 */ - char devmajor[8]; /* 329 */ - char devminor[8]; /* 337 */ - char prefix[155]; /* 345 */ - /* 500 */ -}; +/*@ + @ requires \valid_read(h); + @ assigns \nothing; + @*/ +static int is_valid_checksum_format(const struct tar_posix_header *h) +{ + unsigned int i; + int space_allowed=1; + int all_null=1; + /* No checksum ? */ + /*@ + @ loop assigns i,all_null; + @*/ + for(i=0; i<8; i++) + if(h->chksum[i]!=0) + all_null=0; + if(all_null!=0) + return 1; + /* + * Checksum should be stored as a six digit octal number with leading zeroes followed by a NUL and then a space. + * Various implementations do not adhere to this format, try to handle them + */ + /*@ + @ loop assigns i,space_allowed; + @*/ + for(i=0; i<6; i++) + { + if(h->chksum[i] >= '0' || h->chksum[i] <= '7') + { + space_allowed=0; + continue; + } + if(h->chksum[i] == ' ') + { + if(space_allowed == 0) + return 0; + } + else + return 0; + } + if(h->chksum[6] == 0 || h->chksum[7] == ' ') + return 1; + if((h->chksum[6] >= '0' || h->chksum[6] <= '7') && h->chksum[7] == ' ') + return 1; + return 0; +} + +int is_valid_tar_header(const struct tar_posix_header *h) +{ + /* Do not remove this check. */ + if(memcmp(&h->magic,tar_header_gnu,sizeof(tar_header_gnu))!=0 && + memcmp(&h->magic,tar_header_posix,sizeof(tar_header_posix))!=0) + return 0; + if(is_valid_checksum_format(h)==0) + return 0; + return 1; +} /*@ @ requires buffer_size >= 512; @@ -74,10 +113,10 @@ struct posix_header @ requires file_recovery_new->blocksize > 0; @ requires separation: \separated(&file_hint_tar, buffer+(..), file_recovery, file_recovery_new); @*/ -int header_check_tar(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new) +static int header_check_tar(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new) { - const struct posix_header *h=(const struct posix_header *)buffer; - if(!isspace(h->chksum[0]) && !((unsigned) (h->chksum[0]) - '0' <= 7)) + const struct tar_posix_header *h=(const struct tar_posix_header *)buffer; + if(is_valid_tar_header(h)==0) return 0; if(file_recovery->file_stat!=NULL && file_recovery->file_stat->file_hint==&file_hint_tar) { @@ -95,9 +134,9 @@ int header_check_tar(const unsigned char *buffer, const unsigned int buffer_size @*/ static void register_header_check_tar(file_stat_t *file_stat) { - static const unsigned char tar_header_gnu[6] = { 'u','s','t','a','r',0x00}; - static const unsigned char tar_header_posix[8] = { 'u','s','t','a','r',' ',' ',0x00}; register_header_check(0x101, tar_header_gnu,sizeof(tar_header_gnu), &header_check_tar, file_stat); +#ifndef __FRAMAC__ register_header_check(0x101, tar_header_posix,sizeof(tar_header_posix), &header_check_tar, file_stat); +#endif } #endif diff --git a/src/file_tar.h b/src/file_tar.h index 18528a6..85e02c4 100644 --- a/src/file_tar.h +++ b/src/file_tar.h @@ -25,7 +25,32 @@ extern "C" { #endif -int header_check_tar(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new); +struct tar_posix_header +{ /* byte offset */ + char name[100]; /* 0 */ + char mode[8]; /* 100 */ + char uid[8]; /* 108 */ + char gid[8]; /* 116 */ + char size[12]; /* 124 */ + char mtime[12]; /* 136 */ + char chksum[8]; /* 148 */ + char typeflag; /* 156 */ + char linkname[100]; /* 157 */ + char magic[6]; /* 257 */ + char version[2]; /* 263 */ + char uname[32]; /* 265 */ + char gname[32]; /* 297 */ + char devmajor[8]; /* 329 */ + char devminor[8]; /* 337 */ + char prefix[155]; /* 345 */ + /* 500 */ +}; + +/*@ + @ requires \valid_read(h); + @ assigns \nothing; + @*/ +int is_valid_tar_header(const struct tar_posix_header *h); #ifdef __cplusplus } /* closing brace for extern "C" */ @@ -103,7 +103,7 @@ pstatus_t photorec_find_blocksize(struct ph_param *params, const struct ph_optio file_recovery_new.blocksize=blocksize; file_recovery_new.location.start=offset; if(file_recovery.file_stat!=NULL && file_recovery.file_stat->file_hint==&file_hint_tar && - header_check_tar(buffer-0x200,0x200,0,&file_recovery,&file_recovery_new)) + is_valid_tar_header((const struct tar_posix_header *)(buffer-0x200))) { /* Currently saving a tar, do not check the data for know header */ } else diff --git a/src/photorec_check_header.h b/src/photorec_check_header.h index 1aecd86..203641e 100644 --- a/src/photorec_check_header.h +++ b/src/photorec_check_header.h @@ -146,7 +146,7 @@ inline static pstatus_t photorec_check_header(file_recovery_t *file_recovery, st file_recovery_new.blocksize=blocksize; file_recovery_new.location.start=offset; if(file_recovery->file_stat!=NULL && file_recovery->file_stat->file_hint==&file_hint_tar && - header_check_tar(buffer-0x200,0x200, 0, file_recovery, &file_recovery_new)) + is_valid_tar_header((const struct tar_posix_header *)(buffer-0x200))) { /* Currently saving a tar, do not check the data for know header */ if(options->verbose > 1) { diff --git a/src/qphbs.cpp b/src/qphbs.cpp index e0e6438..4c496e4 100644 --- a/src/qphbs.cpp +++ b/src/qphbs.cpp @@ -98,7 +98,7 @@ pstatus_t QPhotorec::photorec_find_blocksize(alloc_data_t *list_search_space) { file_recovery_t file_recovery_new; if(file_recovery.file_stat!=NULL && file_recovery.file_stat->file_hint==&file_hint_tar && - header_check_tar(buffer-0x200,0x200,0,&file_recovery,&file_recovery_new)) + is_valid_tar_header((const struct tar_posix_header *)(buffer-0x200))) { /* Currently saving a tar, do not check the data for know header */ } else |