8074579: Use more efficient and readable way of checking PKZIP signatures
authormartin
Tue, 10 Mar 2015 14:23:03 -0700
changeset 29389 348a32f79d79
parent 29388 c821b03af80a
child 29390 9927a5ff3ded
8074579: Use more efficient and readable way of checking PKZIP signatures Reviewed-by: sherman
jdk/src/java.base/share/native/libjli/manifest_info.h
jdk/src/java.base/share/native/libjli/parse_manifest.c
jdk/src/java.base/share/native/libzip/zip_util.c
jdk/src/java.base/share/native/libzip/zip_util.h
jdk/src/java.base/unix/native/launcher/jexec.c
--- a/jdk/src/java.base/share/native/libjli/manifest_info.h	Wed Mar 04 17:35:40 2015 -0800
+++ b/jdk/src/java.base/share/native/libjli/manifest_info.h	Tue Mar 10 14:23:03 2015 -0700
@@ -32,13 +32,16 @@
  * Zip file header signatures
  */
 #define SIGSIZ 4                    /* size of all header signatures */
-#define LOCSIG 0x04034b50L          /* "PK\003\004" */
-#define EXTSIG 0x08074b50L          /* "PK\007\008" */
-#define CENSIG 0x02014b50L          /* "PK\001\002" */
-#define ENDSIG 0x06054b50L          /* "PK\005\006" */
 
-#define ZIP64_ENDSIG 0x06064b50L    /* "PK\006\006" */
-#define ZIP64_LOCSIG 0x07064b50L    /* "PK\006\007" */
+#define PKZIP_SIGNATURE_AT(p, b2, b3) \
+  (((p)[0] == 'P') & ((p)[1] == 'K') & ((p)[2] == b2) & ((p)[3] == b3))
+#define CENSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 1, 2)
+#define LOCSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 3, 4)
+#define ENDSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 5, 6)
+#define EXTSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 7, 8)
+#define ZIP64_ENDSIG_AT(p) PKZIP_SIGNATURE_AT(p, 6, 6)
+#define ZIP64_LOCSIG_AT(p) PKZIP_SIGNATURE_AT(p, 6, 7)
+
 /*
  * Header sizes including signatures
  */
--- a/jdk/src/java.base/share/native/libjli/parse_manifest.c	Wed Mar 04 17:35:40 2015 -0800
+++ b/jdk/src/java.base/share/native/libjli/parse_manifest.c	Tue Mar 10 14:23:03 2015 -0700
@@ -138,7 +138,7 @@
         return -1;
     if ((bytes = read(fd, ep, ZIP64_LOCHDR)) < 0)
         return -1;
-    if (GETSIG(ep) == ZIP64_LOCSIG)
+    if (ZIP64_LOCSIG_AT(ep))
        return end64pos;
     return -1;
 }
@@ -176,7 +176,7 @@
         return (-1);
     if ((bytes = read(fd, eb, ENDHDR)) < 0)
         return (-1);
-    if (GETSIG(eb) == ENDSIG) {
+    if (ENDSIG_AT(eb)) {
         return haveZIP64(eb) ? find_end64(fd, eb, pos) : pos;
     }
 
@@ -200,14 +200,11 @@
 
     /*
      * Search backwards from the end of file stopping when the END header
-     * signature is found. (The first condition of the "if" is just a
-     * fast fail, because the GETSIG macro isn't always cheap.  The
-     * final condition protects against false positives.)
+     * signature is found.
      */
     endpos = &buffer[bytes];
     for (cp = &buffer[bytes - ENDHDR]; cp >= &buffer[0]; cp--)
-        if ((*cp == (ENDSIG & 0xFF)) && (GETSIG(cp) == ENDSIG) &&
-          (cp + ENDHDR + ENDCOM(cp) == endpos)) {
+        if (ENDSIG_AT(cp) && (cp + ENDHDR + ENDCOM(cp) == endpos)) {
             (void) memcpy(eb, cp, ENDHDR);
             free(buffer);
             pos = flen - (endpos - cp);
@@ -267,7 +264,7 @@
         if ((bytes = read(fd, buffer, MINREAD)) < 0) {
             return (-1);
         }
-        if (GETSIG(buffer) != ZIP64_ENDSIG) {
+        if (!ZIP64_ENDSIG_AT(buffer)) {
             return -1;
         }
         if ((offset = ZIP64_ENDOFF(buffer)) < (jlong)0) {
@@ -356,7 +353,7 @@
      * Loop through the Central Directory Headers. Note that a valid zip/jar
      * must have an ENDHDR (with ENDSIG) after the Central Directory.
      */
-    while (GETSIG(p) == CENSIG) {
+    while (CENSIG_AT(p)) {
 
         /*
          * If a complete header isn't in the buffer, shift the contents
@@ -403,7 +400,7 @@
                 free(buffer);
                 return (-1);
             }
-            if (GETSIG(locbuf) != LOCSIG) {
+            if (!LOCSIG_AT(locbuf)) {
                 free(buffer);
                 return (-1);
             }
--- a/jdk/src/java.base/share/native/libzip/zip_util.c	Wed Mar 04 17:35:40 2015 -0800
+++ b/jdk/src/java.base/share/native/libzip/zip_util.c	Tue Mar 10 14:23:03 2015 -0700
@@ -281,9 +281,9 @@
     return (cenpos >= 0 &&
             locpos >= 0 &&
             readFullyAt(zip->zfd, buf, sizeof(buf), cenpos) != -1 &&
-            GETSIG(buf) == CENSIG &&
+            CENSIG_AT(buf) &&
             readFullyAt(zip->zfd, buf, sizeof(buf), locpos) != -1 &&
-            GETSIG(buf) == LOCSIG);
+            LOCSIG_AT(buf));
 }
 
 /*
@@ -674,7 +674,7 @@
         method = CENHOW(cp);
         nlen   = CENNAM(cp);
 
-        if (GETSIG(cp) != CENSIG)
+        if (!CENSIG_AT(cp))
             ZIP_FORMAT_ERROR("invalid CEN header (bad signature)");
         if (CENFLG(cp) & 1)
             ZIP_FORMAT_ERROR("invalid CEN header (encrypted entry)");
@@ -827,10 +827,7 @@
 
     // Assumption, zfd refers to start of file. Trivially, reuse errbuf.
     if (readFully(zfd, errbuf, 4) != -1) {  // errors will be handled later
-        if (GETSIG(errbuf) == LOCSIG)
-            zip->locsig = JNI_TRUE;
-        else
-            zip->locsig = JNI_FALSE;
+        zip->locsig = LOCSIG_AT(errbuf) ? JNI_TRUE : JNI_FALSE;
     }
 
     len = zip->len = IO_Lseek(zfd, 0, SEEK_END);
@@ -1284,7 +1281,7 @@
             zip->msg = "error reading zip file";
             return -1;
         }
-        if (GETSIG(loc) != LOCSIG) {
+        if (!LOCSIG_AT(loc)) {
             zip->msg = "invalid LOC header (bad signature)";
             return -1;
         }
--- a/jdk/src/java.base/share/native/libzip/zip_util.h	Wed Mar 04 17:35:40 2015 -0800
+++ b/jdk/src/java.base/share/native/libzip/zip_util.h	Tue Mar 10 14:23:03 2015 -0700
@@ -33,13 +33,14 @@
 /*
  * Header signatures
  */
-#define LOCSIG 0x04034b50L          /* "PK\003\004" */
-#define EXTSIG 0x08074b50L          /* "PK\007\008" */
-#define CENSIG 0x02014b50L          /* "PK\001\002" */
-#define ENDSIG 0x06054b50L          /* "PK\005\006" */
-
-#define ZIP64_ENDSIG 0x06064b50L    /* "PK\006\006" */
-#define ZIP64_LOCSIG 0x07064b50L    /* "PK\006\007" */
+#define PKZIP_SIGNATURE_AT(p, b2, b3) \
+  (((p)[0] == 'P') & ((p)[1] == 'K') & ((p)[2] == b2) & ((p)[3] == b3))
+#define CENSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 1, 2)
+#define LOCSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 3, 4)
+#define ENDSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 5, 6)
+#define EXTSIG_AT(p)       PKZIP_SIGNATURE_AT(p, 7, 8)
+#define ZIP64_ENDSIG_AT(p) PKZIP_SIGNATURE_AT(p, 6, 6)
+#define ZIP64_LOCSIG_AT(p) PKZIP_SIGNATURE_AT(p, 6, 7)
 
 /*
  * Header sizes including signatures
--- a/jdk/src/java.base/unix/native/launcher/jexec.c	Wed Mar 04 17:35:40 2015 -0800
+++ b/jdk/src/java.base/unix/native/launcher/jexec.c	Tue Mar 10 14:23:03 2015 -0700
@@ -323,7 +323,7 @@
             result = BAD_MAGIC_MSG;
 
             // be sure the file is at least a ZIP file
-            if (GETSIG(buf) == LOCSIG) {
+            if (LOCSIG_AT(buf)) {
 
                 off_t flen  = LOCNAM(buf);
                 off_t xlen  = LOCEXT(buf);