Fix bug#1043 -- hanlde long filenames and links (in this case, by complaining

that thay exist and skipping such files when extracting and when archiving.
 -Erik

3 files changed, 71 insertions, 9 deletions

diff --git a/archival/tar.c b/archival/tar.c
index 6dcda53ef..e4bdd0a6c 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -39,6 +39,7 @@
 #include "internal.h"
 #define BB_DECLARE_EXTERN
 #define bb_need_io_error
+#define bb_need_name_longer_then_foo
 #include "messages.c"
 #include <stdio.h>
 #include <dirent.h>
@@ -57,12 +58,13 @@
 #define MINOR(dev) ((dev)&0xff)
 #endif
 
+#define NAME_SIZE       100
 
 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
 struct TarHeader
 {
                                 /* byte offset */
-        char name[100];               /*   0-99 */
+        char name[NAME_SIZE];         /*   0-99 */
         char mode[8];                 /* 100-107 */
         char uid[8];                  /* 108-115 */
         char gid[8];                  /* 116-123 */
@@ -70,7 +72,7 @@ struct TarHeader
         char mtime[12];               /* 136-147 */
         char chksum[8];               /* 148-155 */
         char typeflag;                /* 156-156 */
-        char linkname[100];           /* 157-256 */
+        char linkname[NAME_SIZE];     /* 157-256 */
         char magic[6];                /* 257-262 */
         char version[2];              /* 263-264 */
         char uname[32];               /* 265-296 */
@@ -102,6 +104,8 @@ enum TarFileType
         DIRTYPE  = '5',            /* directory */
         FIFOTYPE = '6',            /* FIFO special */
         CONTTYPE = '7',            /* reserved */
+        GNULONGLINK = 'K',         /* GNU long (>100 chars) link name */
+        GNULONGNAME = 'L',         /* GNU long (>100 chars) file name */
 };
 typedef enum TarFileType TarFileType;
 
@@ -496,6 +500,7 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 {
         int status, tarFd=-1;
         int errorFlag=FALSE;
+        int skipNextHeaderFlag=FALSE;
         TarHeader rawHeader;
         TarInfo header;
         char** tmpList;
@@ -517,7 +522,7 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
         /* Read the tar file, and iterate over it one file at a time */
         while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
 
-                /* First, try to read the header */
+                /* Try to read the header */
                 if ( readTarHeader(&rawHeader, &header) == FALSE ) {
                         if ( *(header.name) == '\0' ) {
                                 goto endgame;
@@ -531,6 +536,19 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
                                 goto endgame;
                 header.tarFd = tarFd;
 
+                /* Skip funky extra GNU headers that precede long files */
+                if ( (header.type == GNULONGNAME) || (header.type == GNULONGLINK) ) {
+                        skipNextHeaderFlag=TRUE;
+                        tarExtractRegularFile(&header, FALSE, FALSE);
+                        continue;
+                }
+                if ( skipNextHeaderFlag == TRUE ) { 
+                        skipNextHeaderFlag=FALSE;
+                        errorMsg(name_longer_then_foo, NAME_SIZE); 
+                        tarExtractRegularFile(&header, FALSE, FALSE);
+                        continue;
+                }
+
 #if defined BB_FEATURE_TAR_EXCLUDE
                 {
                         int skipFlag=FALSE;
@@ -671,7 +689,15 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
                                 if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
                                         errorFlag=TRUE;
                                 break;
+#if 0
+                        /* Handled earlier */
+                        case GNULONGNAME:
+                        case GNULONGLINK:
+                                skipNextHeaderFlag=TRUE;
+                                break;
+#endif
                         default:
+                                errorMsg("Unknown file type '%c' in tar file\n", header.type);
                                 close( tarFd);
                                 return( FALSE);
                 }
@@ -897,6 +923,11 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf, void*
                 return( TRUE);
         }
 
+        if (strlen(fileName) >= NAME_SIZE) {
+                errorMsg(name_longer_then_foo, NAME_SIZE);
+                return ( TRUE);
+        }
+
         if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
                 return( FALSE);
         } 
diff --git a/messages.c b/messages.c
index 34b39f258..f7a772cbd 100644
--- a/messages.c
+++ b/messages.c
@@ -81,9 +81,9 @@
 #if defined bb_need_too_few_args || ! defined BB_DECLARE_EXTERN
         BB_DEF_MESSAGE(too_few_args, "too few arguments\n")
 #endif
-
-
-
+#if defined bb_need_name_longer_then_foo || ! defined BB_DECLARE_EXTERN
+        BB_DEF_MESSAGE(name_longer_then_foo, "Names longer then %d chars not supported.\n")
+#endif
 
 
 #endif /* _BB_MESSAGES_C */
diff --git a/tar.c b/tar.c
index 6dcda53ef..e4bdd0a6c 100644
--- a/tar.c
+++ b/tar.c
@@ -39,6 +39,7 @@
 #include "internal.h"
 #define BB_DECLARE_EXTERN
 #define bb_need_io_error
+#define bb_need_name_longer_then_foo
 #include "messages.c"
 #include <stdio.h>
 #include <dirent.h>
@@ -57,12 +58,13 @@
 #define MINOR(dev) ((dev)&0xff)
 #endif
 
+#define NAME_SIZE       100
 
 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
 struct TarHeader
 {
                                 /* byte offset */
-        char name[100];               /*   0-99 */
+        char name[NAME_SIZE];         /*   0-99 */
         char mode[8];                 /* 100-107 */
         char uid[8];                  /* 108-115 */
         char gid[8];                  /* 116-123 */
@@ -70,7 +72,7 @@ struct TarHeader
         char mtime[12];               /* 136-147 */
         char chksum[8];               /* 148-155 */
         char typeflag;                /* 156-156 */
-        char linkname[100];           /* 157-256 */
+        char linkname[NAME_SIZE];     /* 157-256 */
         char magic[6];                /* 257-262 */
         char version[2];              /* 263-264 */
         char uname[32];               /* 265-296 */
@@ -102,6 +104,8 @@ enum TarFileType
         DIRTYPE  = '5',            /* directory */
         FIFOTYPE = '6',            /* FIFO special */
         CONTTYPE = '7',            /* reserved */
+        GNULONGLINK = 'K',         /* GNU long (>100 chars) link name */
+        GNULONGNAME = 'L',         /* GNU long (>100 chars) file name */
 };
 typedef enum TarFileType TarFileType;
 
@@ -496,6 +500,7 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 {
         int status, tarFd=-1;
         int errorFlag=FALSE;
+        int skipNextHeaderFlag=FALSE;
         TarHeader rawHeader;
         TarInfo header;
         char** tmpList;
@@ -517,7 +522,7 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
         /* Read the tar file, and iterate over it one file at a time */
         while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
 
-                /* First, try to read the header */
+                /* Try to read the header */
                 if ( readTarHeader(&rawHeader, &header) == FALSE ) {
                         if ( *(header.name) == '\0' ) {
                                 goto endgame;
@@ -531,6 +536,19 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
                                 goto endgame;
                 header.tarFd = tarFd;
 
+                /* Skip funky extra GNU headers that precede long files */
+                if ( (header.type == GNULONGNAME) || (header.type == GNULONGLINK) ) {
+                        skipNextHeaderFlag=TRUE;
+                        tarExtractRegularFile(&header, FALSE, FALSE);
+                        continue;
+                }
+                if ( skipNextHeaderFlag == TRUE ) { 
+                        skipNextHeaderFlag=FALSE;
+                        errorMsg(name_longer_then_foo, NAME_SIZE); 
+                        tarExtractRegularFile(&header, FALSE, FALSE);
+                        continue;
+                }
+
 #if defined BB_FEATURE_TAR_EXCLUDE
                 {
                         int skipFlag=FALSE;
@@ -671,7 +689,15 @@ static int readTarFile(const char* tarName, int extractFlag, int listFlag,
                                 if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
                                         errorFlag=TRUE;
                                 break;
+#if 0
+                        /* Handled earlier */
+                        case GNULONGNAME:
+                        case GNULONGLINK:
+                                skipNextHeaderFlag=TRUE;
+                                break;
+#endif
                         default:
+                                errorMsg("Unknown file type '%c' in tar file\n", header.type);
                                 close( tarFd);
                                 return( FALSE);
                 }
@@ -897,6 +923,11 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf, void*
                 return( TRUE);
         }
 
+        if (strlen(fileName) >= NAME_SIZE) {
+                errorMsg(name_longer_then_foo, NAME_SIZE);
+                return ( TRUE);
+        }
+
         if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
                 return( FALSE);
         }