static struct zip_cdir *
_zip_read_eocd(const unsigned char *eocd, const unsigned char *buf, off_t buf_offset, size_t buflen,
unsigned int flags, struct zip_error *error)
{
struct zip_cdir *cd;
const unsigned char *cdp;
zip_uint64_t i, nentry, size, offset;
if (eocd+EOCDLEN > buf+buflen) {
_zip_error_set(error, ZIP_ER_INCONS, 0);
return NULL;
}
cdp = eocd + 8;
/* number of cdir-entries on this disk */
i = _zip_read2(&cdp);
/* number of cdir-entries */
nentry = _zip_read2(&cdp);
if (nentry != i) {
_zip_error_set(error, ZIP_ER_NOZIP, 0);
return NULL;
}
size = _zip_read4(&cdp);
offset = _zip_read4(&cdp);
if (size > ZIP_OFF_MAX || offset > ZIP_OFF_MAX || offset+size > ZIP_OFF_MAX) {
_zip_error_set(error, ZIP_ER_SEEK, EFBIG);
return NULL;
}
if (offset+size > (zip_uint64_t)(buf_offset + (eocd-buf))) {
/* cdir spans past EOCD record */
_zip_error_set(error, ZIP_ER_INCONS, 0);
return NULL;
}
if ((flags & ZIP_CHECKCONS) && offset+size != (zip_uint64_t)(buf_offset + (eocd-buf))) {
_zip_error_set(error, ZIP_ER_INCONS, 0);
return NULL;
}
if ((cd=_zip_cdir_new(nentry, error)) == NULL)
return NULL;
cd->size = (off_t)size;
cd->offset = (off_t)offset;
return cd;
}
static struct zip_cdir *
_zip_readcdir(FILE *fp, unsigned char *buf, unsigned char *eocd, int buflen,
int flags, struct zip_error *error)
{
struct zip_cdir *cd;
unsigned char *cdp, **bufp;
int i, comlen, nentry;
unsigned int left;
comlen = buf + buflen - eocd - EOCDLEN;
if (comlen < 0) {
/* not enough bytes left for comment */
_zip_error_set(error, ZIP_ER_NOZIP, 0);
return NULL;
}
/* check for end-of-central-dir magic */
if (memcmp(eocd, EOCD_MAGIC, 4) != 0) {
_zip_error_set(error, ZIP_ER_NOZIP, 0);
return NULL;
}
if (memcmp(eocd+4, "\0\0\0\0", 4) != 0) {
_zip_error_set(error, ZIP_ER_MULTIDISK, 0);
return NULL;
}
cdp = eocd + 8;
/* number of cdir-entries on this disk */
i = _zip_read2(&cdp);
/* number of cdir-entries */
nentry = _zip_read2(&cdp);
if ((cd=_zip_cdir_new(nentry, error)) == NULL)
return NULL;
cd->size = _zip_read4(&cdp);
cd->offset = _zip_read4(&cdp);
cd->comment = NULL;
cd->comment_len = _zip_read2(&cdp);
if ((comlen < cd->comment_len) || (cd->nentry != i)) {
_zip_error_set(error, ZIP_ER_NOZIP, 0);
free(cd);
return NULL;
}
if ((flags & ZIP_CHECKCONS) && comlen != cd->comment_len) {
_zip_error_set(error, ZIP_ER_INCONS, 0);
free(cd);
return NULL;
}
if (cd->comment_len) {
if ((cd->comment=(char *)_zip_memdup(eocd+EOCDLEN,
cd->comment_len, error))
== NULL) {
free(cd);
return NULL;
}
}
if (cd->size < (unsigned int)(eocd-buf)) {
/* if buffer already read in, use it */
cdp = eocd - cd->size;
bufp = &cdp;
}
else {
/* go to start of cdir and read it entry by entry */
bufp = NULL;
clearerr(fp);
fseeko(fp, cd->offset, SEEK_SET);
/* possible consistency check: cd->offset =
len-(cd->size+cd->comment_len+EOCDLEN) ? */
if (ferror(fp) || ((unsigned long)ftello(fp) != cd->offset)) {
/* seek error or offset of cdir wrong */
if (ferror(fp))
_zip_error_set(error, ZIP_ER_SEEK, errno);
else
_zip_error_set(error, ZIP_ER_NOZIP, 0);
free(cd);
return NULL;
}
}
left = cd->size;
i=0;
do {
if (i == cd->nentry && left > 0) {
/* Infozip extension for more than 64k entries:
nentries wraps around, size indicates correct EOCD */
_zip_cdir_grow(cd, cd->nentry+0x10000, error);
}
if ((_zip_dirent_read(cd->entry+i, fp, bufp, &left, 0, error)) < 0) {
cd->nentry = i;
_zip_cdir_free(cd);
return NULL;
}
i++;
} while (i<cd->nentry);
return cd;
}
static struct zip_cdir *
_zip_readcdir(FILE *fp, off_t buf_offset, unsigned char *buf, unsigned char *eocd, int buflen,
int flags, struct zip_error *error)
{
struct zip_cdir *cd;
unsigned char *cdp, **bufp;
int i, comlen, nentry;
zip_uint32_t left;
comlen = buf + buflen - eocd - EOCDLEN;
if (comlen < 0) {
/* not enough bytes left for comment */
_zip_error_set(error, ZIP_ER_NOZIP, 0);
return NULL;
}
/* check for end-of-central-dir magic */
if (memcmp(eocd, EOCD_MAGIC, 4) != 0) {
_zip_error_set(error, ZIP_ER_NOZIP, 0);
return NULL;
}
if (memcmp(eocd+4, "\0\0\0\0", 4) != 0) {
_zip_error_set(error, ZIP_ER_MULTIDISK, 0);
return NULL;
}
cdp = eocd + 8;
/* number of cdir-entries on this disk */
i = _zip_read2(&cdp);
/* number of cdir-entries */
nentry = _zip_read2(&cdp);
if ((cd=_zip_cdir_new(nentry, error)) == NULL)
return NULL;
cd->size = _zip_read4(&cdp);
cd->offset = _zip_read4(&cdp);
cd->comment = NULL;
cd->comment_len = _zip_read2(&cdp);
/* without checking the ZIP_CHECKCONS flag we'll not able even to open inconsistent
archives at this place, which would break bc in PHP */
if ((ZIP_CHECKCONS == (flags & ZIP_CHECKCONS)) && ((zip_uint64_t)cd->offset)+cd->size > buf_offset + (eocd-buf)) {
/* cdir spans past EOCD record */
_zip_error_set(error, ZIP_ER_INCONS, 0);
cd->nentry = 0;
_zip_cdir_free(cd);
return NULL;
}
if ((comlen < cd->comment_len) || (cd->nentry != i)) {
_zip_error_set(error, ZIP_ER_NOZIP, 0);
cd->nentry = 0;
_zip_cdir_free(cd);
return NULL;
}
if ((flags & ZIP_CHECKCONS) && comlen != cd->comment_len) {
_zip_error_set(error, ZIP_ER_INCONS, 0);
cd->nentry = 0;
_zip_cdir_free(cd);
return NULL;
}
if (cd->comment_len) {
if ((cd->comment=(char *)_zip_memdup(eocd+EOCDLEN,
cd->comment_len, error))
== NULL) {
cd->nentry = 0;
_zip_cdir_free(cd);
return NULL;
}
}
/* the first if branch goes the old way of libzip 0.9 so we don't loose
the bc for reading inconsistent files */
if ((ZIP_CHECKCONS != (flags & ZIP_CHECKCONS)) && cd->size < (unsigned int)(eocd-buf)) {
cdp = eocd - cd->size;
bufp = &cdp;
}
else if (cd->offset >= buf_offset) {
/* if buffer already read in, use it */
cdp = buf + (cd->offset - buf_offset);
bufp = &cdp;
}
else {
/* go to start of cdir and read it entry by entry */
bufp = NULL;
clearerr(fp);
fseeko(fp, cd->offset, SEEK_SET);
/* possible consistency check: cd->offset =
len-(cd->size+cd->comment_len+EOCDLEN) ? */
if (ferror(fp) || ((unsigned long)ftello(fp) != cd->offset)) {
/* seek error or offset of cdir wrong */
if (ferror(fp))
_zip_error_set(error, ZIP_ER_SEEK, errno);
else
_zip_error_set(error, ZIP_ER_NOZIP, 0);
cd->nentry = 0;
_zip_cdir_free(cd);
return NULL;
}
}
left = cd->size;
i=0;
while (i<cd->nentry && left > 0) {
if ((_zip_dirent_read(cd->entry+i, fp, bufp, &left, 0, error)) < 0) {
cd->nentry = i;
_zip_cdir_free(cd);
return NULL;
}
i++;
if (i == cd->nentry && left > 0) {
/* Infozip extension for more than 64k entries:
nentries wraps around, size indicates correct EOCD */
if (_zip_cdir_grow(cd, cd->nentry+ZIP_UINT16_MAX, error) < 0) {
cd->nentry = i;
_zip_cdir_free(cd);
return NULL;
}
}
}
cd->nentry = i;
return cd;
}
