static jboolean verifyEND(jzfile *zip, jlong endpos, char *endbuf) {
/* ENDSIG matched, however the size of file comment in it does not
match the real size. One "common" cause for this problem is some
"extra" bytes are padded at the end of the zipfile.
Let's do some extra verification, we don't care about the performance
in this situation.
*/
jlong cenpos = endpos - ENDSIZ(endbuf);
jlong locpos = cenpos - ENDOFF(endbuf);
char buf[4];
return (cenpos >= 0 &&
locpos >= 0 &&
readFullyAt(zip->zfd, buf, sizeof(buf), cenpos) != -1 &&
CENSIG_AT(buf) &&
readFullyAt(zip->zfd, buf, sizeof(buf), locpos) != -1 &&
LOCSIG_AT(buf));
}
/*
* Check if the given file is a JAR file.
*
* Parameters:
* path - the path to the file to check for JAR magic.
*
* Returns:
* This function return NULL on success. Otherwise, errno is set, and it
* returns a message that indicates what caused the failure.
*/
const char * isJar(const char * path) {
const char * result = BAD_FILE_MSG;
int fd = open(path, O_RDONLY);
if (fd != -1) {
unsigned char buf[CHUNK_SIZE];
ssize_t count = read(fd, buf, CHUNK_SIZE);
if (count >= MIN_SIZE) {
result = BAD_MAGIC_MSG;
// be sure the file is at least a ZIP file
if (LOCSIG_AT(buf)) {
off_t flen = LOCNAM(buf);
off_t xlen = LOCEXT(buf);
off_t start = LOCHDR + flen;
off_t end = start + xlen;
if (end <= count) {
while (start < end) {
off_t xhid = SH(buf, start);
off_t xdlen = SH(buf, start + 2);
start += 4 + xdlen;
if (xhid == 0xcafe) {
// found the JAR magic
result = NULL;
break;
}
}
}
}
}
if (result != NULL) {
errno = BAD_MAGIC;
}
close (fd);
}
return (result);
}
jzfile *
ZIP_Put_In_Cache0(const char *name, ZFILE zfd, char **pmsg, jlong lastModified,
jboolean usemmap)
{
char errbuf[256];
jlong len;
jzfile *zip;
if ((zip = allocZip(name)) == NULL) {
return NULL;
}
#ifdef USE_MMAP
zip->usemmap = usemmap;
#endif
zip->refs = 1;
zip->lastModified = lastModified;
if (zfd == -1) {
if (pmsg && getLastErrorString(errbuf, sizeof(errbuf)) > 0)
*pmsg = strdup(errbuf);
freeZip(zip);
return NULL;
}
// Assumption, zfd refers to start of file. Trivially, reuse errbuf.
if (readFully(zfd, errbuf, 4) != -1) { // errors will be handled later
zip->locsig = LOCSIG_AT(errbuf) ? JNI_TRUE : JNI_FALSE;
}
len = zip->len = IO_Lseek(zfd, 0, SEEK_END);
if (len <= 0) {
if (len == 0) { /* zip file is empty */
if (pmsg) {
*pmsg = strdup("zip file is empty");
}
} else { /* error */
if (pmsg && getLastErrorString(errbuf, sizeof(errbuf)) > 0)
*pmsg = strdup(errbuf);
}
ZFILE_Close(zfd);
freeZip(zip);
return NULL;
}
zip->zfd = zfd;
if (readCEN(zip, -1) < 0) {
/* An error occurred while trying to read the zip file */
if (pmsg != 0) {
/* Set the zip error message */
if (zip->msg != NULL)
*pmsg = strdup(zip->msg);
}
freeZip(zip);
return NULL;
}
MLOCK(zfiles_lock);
zip->next = zfiles;
zfiles = zip;
MUNLOCK(zfiles_lock);
return zip;
}
