* fcc.h fcc_gprin.c fcc_maybe.c fcc_skip.c fcc_sseq.c

	Store the time offset from the os_context in the credentials cache.
	When applications open the credentials cache, they will set the
	os_context time offset if kdc_timesync is set and the os_context
	time offset has not yet been set.
  Note: The time offset is stored during krb5_cc_initialize, so the os_context
	should be set prior to this operation.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@7461 dc483132-0cff-0310-8789-dd5450dbe970

5 files changed, 154 insertions, 48 deletions

diff --git a/src/lib/krb5/ccache/file/fcc.h b/src/lib/krb5/ccache/file/fcc.h
index bd3f8c368..e17d437ab 100644
--- a/src/lib/krb5/ccache/file/fcc.h
+++ b/src/lib/krb5/ccache/file/fcc.h
@@ -61,6 +61,16 @@
 #define	FCC_OPEN_RDWR		2
 #define	FCC_OPEN_RDONLY		3
 
+/* Credential file header tags.
+ * The header tags are constructed as:
+ *	krb5_ui_2	tag
+ *	krb5_ui_2	len
+ *	krb5_octet	data[len]
+ * This format allows for older versions of the fcc processing code to skip
+ * past unrecognized tag formats.
+ */
+#define FCC_TAG_DELTATIME	1
+
 #ifndef TKT_ROOT
 #ifdef MSDOS_FILESYSTEM
 #define TKT_ROOT "\\tkt"
diff --git a/src/lib/krb5/ccache/file/fcc_gprin.c b/src/lib/krb5/ccache/file/fcc_gprin.c
index fbd35ff85..97369db01 100644
--- a/src/lib/krb5/ccache/file/fcc_gprin.c
+++ b/src/lib/krb5/ccache/file/fcc_gprin.c
@@ -47,13 +47,16 @@ krb5_fcc_get_principal(context, id, princ)
    krb5_principal *princ;
 {
      krb5_error_code kret = KRB5_OK;
+     krb5_fcc_data *data = (krb5_fcc_data *)id->data;
 
      MAYBE_OPEN(context, id, FCC_OPEN_RDONLY);
-     /* make sure we're beyond the vno */
-     lseek(((krb5_fcc_data *) id->data)->fd, sizeof(krb5_int16), SEEK_SET);
-
+     
+     /* make sure we're beyond the header */
+     kret = krb5_fcc_skip_header(context, id);
+     if (kret) goto done;
      kret = krb5_fcc_read_principal(context, id, princ);
 
+done:
      MAYBE_CLOSE(context, id, kret);
      return kret;
 }
diff --git a/src/lib/krb5/ccache/file/fcc_maybe.c b/src/lib/krb5/ccache/file/fcc_maybe.c
index 2b4961e95..5ce020d17 100644
--- a/src/lib/krb5/ccache/file/fcc_maybe.c
+++ b/src/lib/krb5/ccache/file/fcc_maybe.c
@@ -208,12 +208,16 @@ krb5_fcc_close_file (context, id)
 
 krb5_error_code
 krb5_fcc_open_file (context, id, mode)
-   krb5_context context;
+    krb5_context context;
     krb5_ccache id;
     int mode;
 {
+     krb5_os_context os_ctx = (krb5_os_context)context->os_context;
      krb5_fcc_data *data = (krb5_fcc_data *)id->data;
      krb5_ui_2 fcc_fvno;
+     krb5_ui_2 fcc_flen;
+     krb5_ui_2 fcc_tag;
+     krb5_ui_2 fcc_taglen;
      int fd;
      int open_flag;
      krb5_error_code retval = 0;
@@ -261,43 +265,114 @@ krb5_fcc_open_file (context, id, mode)
 	     (void) close(fd);
 	     return (cnt == -1) ? krb5_fcc_interpret(context, errsave) : KRB5_CC_IO;
 	 }
-     } else {
-	 /* verify a valid version number is there */
-	 if (read(fd, (char *)&fcc_fvno, sizeof(fcc_fvno)) !=
-	     sizeof(fcc_fvno)) {
-	     (void) fcc_lock_file(data, fd, UNLOCK_IT);
-	     (void) close(fd);
-	     return KRB5_CC_FORMAT;
+
+	 data->fd = fd;
+	 
+	 if (data->version == KRB5_FCC_FVNO_4) {
+	     /* V4 of the credentials cache format allows for header tags */
+
+	     fcc_flen = (2*sizeof(krb5_ui_2) + 2*sizeof(krb5_int32));
+
+	     /* Write header length */
+	     retval = krb5_fcc_store_ui_2(context, id, (krb5_int32)fcc_flen);
+	     if (retval) goto done;
+
+	     /* Write time offset tag */
+	     fcc_tag = FCC_TAG_DELTATIME;
+	     fcc_taglen = 2*sizeof(krb5_int32);
+
+	     retval = krb5_fcc_store_ui_2(context, id, (krb5_int32)fcc_tag);
+	     if (retval) goto done;
+	     retval = krb5_fcc_store_ui_2(context, id, (krb5_int32)fcc_taglen);
+	     if (retval) goto done;
+	     retval = krb5_fcc_store_int32(context, id, os_ctx->time_offset);
+	     if (retval) goto done;
+	     retval = krb5_fcc_store_int32(context, id, os_ctx->usec_offset);
+	     if (retval) goto done;
 	 }
-	 if ((fcc_fvno != htons(KRB5_FCC_FVNO_4)) &&
-	     (fcc_fvno != htons(KRB5_FCC_FVNO_3)) &&
-	     (fcc_fvno != htons(KRB5_FCC_FVNO_2)) &&
-	     (fcc_fvno != htons(KRB5_FCC_FVNO_1))) {
-	     (void) fcc_lock_file(data, fd, UNLOCK_IT);
-	     (void) close(fd);
-	     return KRB5_CCACHE_BADVNO;
+	 goto done;
+     }
+
+     /* verify a valid version number is there */
+     if (read(fd, (char *)&fcc_fvno, sizeof(fcc_fvno)) !=
+	 sizeof(fcc_fvno)) {
+	 (void) fcc_lock_file(data, fd, UNLOCK_IT);
+	 (void) close(fd);
+	 return KRB5_CC_FORMAT;
+     }
+     if ((fcc_fvno != htons(KRB5_FCC_FVNO_4)) &&
+	 (fcc_fvno != htons(KRB5_FCC_FVNO_3)) &&
+	 (fcc_fvno != htons(KRB5_FCC_FVNO_2)) &&
+	 (fcc_fvno != htons(KRB5_FCC_FVNO_1)))
+     {
+	 retval = KRB5_CCACHE_BADVNO;
+	 goto done;
+     }
+
+     data->version = ntohs(fcc_fvno);
+     data->fd = fd;
+
+     if (data->version == KRB5_FCC_FVNO_4) {
+	 char buf[1024];
+
+	 if (krb5_fcc_read_ui_2(context, id, &fcc_flen) ||
+	     (fcc_flen > sizeof(buf)))
+	 {
+	     retval = KRB5_CC_FORMAT;
+	     goto done;
 	 }
-	if (fcc_fvno == htons(KRB5_FCC_FVNO_4)) {
-     	    krb5_ui_2 fcc_flen;
-	    char buf[1024];
-	    
-	    if (read(fd, (char *)&fcc_flen, sizeof(fcc_flen)) 
-		!= sizeof(fcc_flen)) {
-		     (void) fcc_lock_file(data, fd, UNLOCK_IT);
-		     (void) close(fd);
-		     return KRB5_CC_FORMAT;
-	    }
-	    /* Skip past the header info for now */
-	    if ((fcc_flen = htons(fcc_flen)) != 0) {
-	        if ((krb5_ui_2) read(fd, buf, fcc_flen) != fcc_flen) {
-		     (void) fcc_lock_file(data, fd, UNLOCK_IT);
-		     (void) close(fd);
-		     return KRB5_CC_FORMAT;
-		}
-	    }
-	}
-	data->version = ntohs(fcc_fvno);
-    }
-    data->fd = fd;
-    return 0;
+
+	 while (fcc_flen) {
+	     if ((fcc_flen < (2 * sizeof(krb5_ui_2))) ||
+		 krb5_fcc_read_ui_2(context, id, &fcc_tag) ||
+		 krb5_fcc_read_ui_2(context, id, &fcc_taglen) ||
+		 (fcc_taglen > (fcc_flen - 2*sizeof(krb5_ui_2))))
+	     {
+		 retval = KRB5_CC_FORMAT;
+		 goto done;
+	     }
+
+	     switch (fcc_tag) {
+	     case FCC_TAG_DELTATIME:
+		 if (fcc_taglen != 2*sizeof(krb5_int32)) {
+		     retval = KRB5_CC_FORMAT;
+		     goto done;
+		 }
+		 if (!(context->library_options & KRB5_LIBOPT_SYNC_KDCTIME) ||
+		     (os_ctx->os_flags & KRB5_OS_TOFFSET_VALID))
+		 {
+		     if (krb5_fcc_read(context, id, buf, fcc_taglen)) {
+			 retval = KRB5_CC_FORMAT;
+			 goto done;
+		     }
+		     break;
+		 }
+		 if (krb5_fcc_read_int32(context, id, &os_ctx->time_offset) ||
+		     krb5_fcc_read_int32(context, id, &os_ctx->usec_offset))
+		 {
+		     retval = KRB5_CC_FORMAT;
+		     goto done;
+		 }
+		 os_ctx->os_flags =
+		     ((os_ctx->os_flags & ~KRB5_OS_TOFFSET_TIME) |
+		      KRB5_OS_TOFFSET_VALID);
+		 break;
+	     default:
+		 if (fcc_taglen && krb5_fcc_read(context,id,buf,fcc_taglen)) {
+		     retval = KRB5_CC_FORMAT;
+		     goto done;
+		 }
+		 break;
+	     }
+	     fcc_flen -= (2*sizeof(krb5_ui_2) + fcc_taglen);
+	 }
+     }
+
+done:
+     if (retval) {
+	 data->fd = -1;
+	 (void) fcc_lock_file(data, fd, UNLOCK_IT);
+	 (void) close(fd);
+     }
+     return retval;
 }
diff --git a/src/lib/krb5/ccache/file/fcc_skip.c b/src/lib/krb5/ccache/file/fcc_skip.c
index 15aa43bd2..c54cfe389 100644
--- a/src/lib/krb5/ccache/file/fcc_skip.c
+++ b/src/lib/krb5/ccache/file/fcc_skip.c
@@ -29,6 +29,24 @@
 #include "fcc.h"
 
 krb5_error_code
+krb5_fcc_skip_header(context, id)
+   krb5_context context;
+   krb5_ccache id;
+{
+     krb5_fcc_data *data = (krb5_fcc_data *)id->data;
+     krb5_error_code kret;
+     krb5_ui_2 fcc_flen;
+
+     lseek(data->fd, sizeof(krb5_ui_2), SEEK_SET);
+     if (data->version == KRB5_FCC_FVNO_4) {
+	 kret = krb5_fcc_read_ui_2(context, id, &fcc_flen);
+	 if (kret) return kret;
+     }
+     lseek(data->fd, fcc_flen, SEEK_CUR);
+     return KRB5_OK;
+}
+
+krb5_error_code
 krb5_fcc_skip_principal(context, id)
    krb5_context context;
    krb5_ccache id;
@@ -43,5 +61,3 @@ krb5_fcc_skip_principal(context, id)
      krb5_free_principal(context, princ);
      return KRB5_OK;
 }
-
-     
diff --git a/src/lib/krb5/ccache/file/fcc_sseq.c b/src/lib/krb5/ccache/file/fcc_sseq.c
index c2d1645c1..dac38941c 100644
--- a/src/lib/krb5/ccache/file/fcc_sseq.c
+++ b/src/lib/krb5/ccache/file/fcc_sseq.c
@@ -48,6 +48,7 @@ krb5_fcc_start_seq_get(context, id, cursor)
 {
      krb5_fcc_cursor *fcursor;
      krb5_error_code kret = KRB5_OK;
+     krb5_fcc_data *data = (krb5_fcc_data *)id->data;
      
      fcursor = (krb5_fcc_cursor *) malloc(sizeof(krb5_fcc_cursor));
      if (fcursor == NULL)
@@ -59,16 +60,17 @@ krb5_fcc_start_seq_get(context, id, cursor)
 	      return kret;
 	  }
      }
-     else
-	  /* seek after the version number */
-	  lseek(((krb5_fcc_data *) id->data)->fd, sizeof(krb5_int16), SEEK_SET);
 
      /* Make sure we start reading right after the primary principal */
+     kret = krb5_fcc_skip_header(context, id);
+     if (kret) goto done;
+     kret = krb5_fcc_skip_principal(context, id);
+     if (kret) goto done;
 
-     krb5_fcc_skip_principal(context, id);
-     fcursor->pos = lseek(((krb5_fcc_data *) id->data)->fd, 0, SEEK_CUR);
+     fcursor->pos = lseek(data->fd, 0, SEEK_CUR);
      *cursor = (krb5_cc_cursor) fcursor;
 
+done:
      MAYBE_CLOSE(context, id, kret);
      return kret;
 }