* scc.h scc_gprin.c scc_maybe.c scc_skip.c scc_sseq.c

	Store and retrieve the os_context time offset from the
	credentials cache.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@7465 dc483132-0cff-0310-8789-dd5450dbe970

5 files changed, 221 insertions, 113 deletions

diff --git a/src/lib/krb5/ccache/stdio/scc.h b/src/lib/krb5/ccache/stdio/scc.h
index aaa75b8..627eb3a 100644
--- a/src/lib/krb5/ccache/stdio/scc.h
+++ b/src/lib/krb5/ccache/stdio/scc.h
@@ -53,6 +53,16 @@
 #define	SCC_OPEN_RDWR		2
 #define	SCC_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 SCC_TAG_DELTATIME	1
+
 #ifndef TKT_ROOT
 #define TKT_ROOT "/tmp/tkt"
 #endif
diff --git a/src/lib/krb5/ccache/stdio/scc_gprin.c b/src/lib/krb5/ccache/stdio/scc_gprin.c
index 3f6c90d..5fbc482 100644
--- a/src/lib/krb5/ccache/stdio/scc_gprin.c
+++ b/src/lib/krb5/ccache/stdio/scc_gprin.c
@@ -49,11 +49,13 @@ krb5_scc_get_principal(context, id, princ)
      krb5_error_code kret;
 
      MAYBE_OPEN (context, id, SCC_OPEN_RDONLY);
-     /* skip over vno at beginning of file */
-     fseek(((krb5_scc_data *) id->data)->file, sizeof(krb5_int16), 0);
+
+     kret = krb5_scc_skip_header(context, id);
+     if (kret) goto done;
 
      kret = krb5_scc_read_principal(context, id, princ);
 
+done:
      MAYBE_CLOSE (context, id, kret);
      return kret;
 }
diff --git a/src/lib/krb5/ccache/stdio/scc_maybe.c b/src/lib/krb5/ccache/stdio/scc_maybe.c
index 2e09b3d..ebddd05 100644
--- a/src/lib/krb5/ccache/stdio/scc_maybe.c
+++ b/src/lib/krb5/ccache/stdio/scc_maybe.c
@@ -70,128 +70,202 @@ krb5_scc_close_file (context, id)
 
 krb5_error_code
 krb5_scc_open_file (context, id, mode)
-   krb5_context context;
+    krb5_context context;
     krb5_ccache id;
     int mode;
 {
-     char fvno_bytes[2];	/* In nework standard byte order, big endian */
-     krb5_scc_data *data;
-     FILE *f;
-     char *open_flag;
-     krb5_error_code retval;
-
-     data = (krb5_scc_data *) id->data;
-     if (data->file) {
-	  /* Don't know what state it's in; shut down and start anew.  */
-	  (void) krb5_unlock_file(context, fileno(data->file));
-	  (void) fclose (data->file);
-	  data->file = 0;
-     }
+    krb5_os_context os_ctx = (krb5_os_context) context->os_context;
+    krb5_scc_data *data = (krb5_scc_data *) id->data;
+    char fvno_bytes[2];		/* In nework byte order */
+    krb5_ui_2 scc_vno;
+    krb5_ui_2 scc_tag;
+    krb5_ui_2 scc_taglen;
+    krb5_ui_2 scc_hlen;
+    FILE *f;
+    char *open_flag;
+    krb5_error_code retval = 0;
+    
+    if (data->file) {
+	/* Don't know what state it's in; shut down and start anew.  */
+	(void) krb5_unlock_file(context, fileno(data->file));
+	(void) fclose (data->file);
+	data->file = 0;
+    }
 #ifdef ANSI_STDIO
-     switch(mode) {
-     case SCC_OPEN_AND_ERASE:
-	 unlink(data->filename);
-	 /* XXX should do an exclusive open here, but no way to do */
-	 /* this under stdio */
-	 open_flag = "wb+";
-	 break;
-     case SCC_OPEN_RDWR:
-	 open_flag = "rb+";
-	 break;
-     case SCC_OPEN_RDONLY:
-     default:
-	 open_flag = "rb";
-	 break;
-     }
+    switch(mode) {
+    case SCC_OPEN_AND_ERASE:
+	unlink(data->filename);
+	/* XXX should do an exclusive open here, but no way to do */
+	/* this under stdio */
+	open_flag = "wb+";
+	break;
+    case SCC_OPEN_RDWR:
+	open_flag = "rb+";
+	break;
+    case SCC_OPEN_RDONLY:
+    default:
+	open_flag = "rb";
+	break;
+    }
 #else
-     switch(mode) {
-     case SCC_OPEN_AND_ERASE:
-	 unlink(data->filename);
-	 /* XXX should do an exclusive open here, but no way to do */
-	 /* this under stdio */
-	 open_flag = "w+";
-	 break;
-     case SCC_OPEN_RDWR:
-	 open_flag = "r+";
-	 break;
-     case SCC_OPEN_RDONLY:
-     default:
-	 open_flag = "r";
-	 break;
-     }
+    switch(mode) {
+    case SCC_OPEN_AND_ERASE:
+	unlink(data->filename);
+	/* XXX should do an exclusive open here, but no way to do */
+	/* this under stdio */
+	open_flag = "w+";
+	break;
+    case SCC_OPEN_RDWR:
+	open_flag = "r+";
+	break;
+    case SCC_OPEN_RDONLY:
+    default:
+	open_flag = "r";
+	break;
+    }
 #endif
 
-     f = fopen (data->filename, open_flag);
-     if (!f)
-	  return krb5_scc_interpret (context, errno);
+    f = fopen (data->filename, open_flag);
+    if (!f)
+	return krb5_scc_interpret (context, errno);
 #ifdef HAS_SETVBUF
-     setvbuf(f, data->stdio_buffer, _IOFBF, sizeof (data->stdio_buffer));
+    setvbuf(f, data->stdio_buffer, _IOFBF, sizeof (data->stdio_buffer));
 #else
-     setbuf (f, data->stdio_buffer);
+    setbuf (f, data->stdio_buffer);
 #endif
-     switch (mode) {
-     case SCC_OPEN_RDONLY:
-	 if ((retval = krb5_lock_file(context,fileno(f),KRB5_LOCKMODE_SHARED))){
-	     (void) fclose(f);
-	     return retval;
-	 }
-	 break;
-     case SCC_OPEN_RDWR:
-     case SCC_OPEN_AND_ERASE:
-	 if ((retval = krb5_lock_file(context, fileno(f), 
-				      KRB5_LOCKMODE_EXCLUSIVE))) {
-	     (void) fclose(f);
-	     return retval;
-	 }
-	 break;
-     }
-     if (mode == SCC_OPEN_AND_ERASE) {
-	 /* write the version number */
-	 int errsave;
+    switch (mode) {
+    case SCC_OPEN_RDONLY:
+	if ((retval = krb5_lock_file(context,fileno(f),KRB5_LOCKMODE_SHARED))){
+	    (void) fclose(f);
+	    return retval;
+	}
+	break;
+    case SCC_OPEN_RDWR:
+    case SCC_OPEN_AND_ERASE:
+	if ((retval = krb5_lock_file(context, fileno(f), 
+				     KRB5_LOCKMODE_EXCLUSIVE))) {
+	    (void) fclose(f);
+	    return retval;
+	}
+	break;
+    }
+    if (mode == SCC_OPEN_AND_ERASE) {
+	/* write the version number */
+	int errsave;
+
+	data->file = f;
+	data->version = context->scc_default_format;
+	retval = krb5_scc_store_ui_2(context, id, data->version);
+	if (retval) goto done;
 
-	 fvno_bytes[0] = (context->scc_default_format >> 8) & 0xFF;
-	 fvno_bytes[1] = context->scc_default_format & 0xFF;
-	 data->version = context->scc_default_format;
-	 if (!fwrite((char *)fvno_bytes, sizeof(fvno_bytes), 1, f)) {
-	     errsave = errno;
-	     (void) krb5_unlock_file(context, fileno(f));
-	     (void) fclose(f);
-	     return krb5_scc_interpret(context, errsave);
-	 }
-     } else {
-	 /* verify a valid version number is there */
-	 if (!fread((char *)fvno_bytes, sizeof(fvno_bytes), 1, f)) {
-	     (void) krb5_unlock_file(context, fileno(f));
-	     (void) fclose(f);
-	     return KRB5_CC_FORMAT;
-	 }
-	 data->version = (fvno_bytes[0] << 8) + fvno_bytes[1];
-	 if ((data->version != KRB5_SCC_FVNO_1) &&
-	     (data->version != KRB5_SCC_FVNO_2) &&
-	     (data->version != KRB5_SCC_FVNO_3) &&
-	     (data->version != KRB5_SCC_FVNO_4)) {
-	     (void) krb5_unlock_file(context, fileno(f));
-	     (void) fclose(f);
-	     return KRB5_CCACHE_BADVNO;
-	 }
 	if (data->version == KRB5_SCC_FVNO_4) {
-	    char buf[1024];
-	    int len;
+	    scc_hlen = 0;
+
+	    if (os_ctx->os_flags & KRB5_OS_TOFFSET_VALID)
+                 scc_hlen += (2*sizeof(krb5_ui_2) + 2*sizeof(krb5_int32));
+ 
+	    /* Write header length */
+	    retval = krb5_scc_store_ui_2(context, id, (krb5_int32)scc_hlen);
+	    if (retval) goto done;
+ 
+	    if (os_ctx->os_flags & KRB5_OS_TOFFSET_VALID) {
+		/* Write time offset tag */
+		scc_tag = SCC_TAG_DELTATIME;
+		scc_taglen = 2*sizeof(krb5_int32);
+                 
+		retval = krb5_scc_store_ui_2(context,id,(krb5_int32)scc_tag);
+		if (retval) goto done;
+		retval = krb5_scc_store_ui_2(context,id,(krb5_int32)scc_taglen);
+		if (retval) goto done;
+		retval = krb5_scc_store_int32(context,id,os_ctx->time_offset);
+		if (retval) goto done;
+		retval = krb5_scc_store_int32(context,id,os_ctx->usec_offset);
+		if (retval) goto done;
+	    }
+	}
+	goto done;
+    }
+
+    /* verify a valid version number is there */
+    if (!fread((char *)fvno_bytes, sizeof(fvno_bytes), 1, f))
+    {
+	retval = KRB5_CC_FORMAT;
+	goto done;
+    }
+    data->version = (fvno_bytes[0] << 8) + fvno_bytes[1];
+    if ((data->version != KRB5_SCC_FVNO_1) &&
+	(data->version != KRB5_SCC_FVNO_2) &&
+	(data->version != KRB5_SCC_FVNO_3) &&
+	(data->version != KRB5_SCC_FVNO_4))
+    {
+	retval = KRB5_CCACHE_BADVNO;
+	goto done;
+    }
+
+    data->file = f;
+    
+    if (data->version == KRB5_SCC_FVNO_4) {
+	char buf[1024];
 
-	    if (!fread((char *)fvno_bytes, sizeof(fvno_bytes), 1, f)) {
-	     	(void) krb5_unlock_file(context, fileno(f));
-	     	(void) fclose(f);
-	     	return KRB5_CC_FORMAT;
+	if (krb5_scc_read_ui_2(context, id, &scc_hlen) ||
+	    (scc_hlen > sizeof(buf)))
+	{
+	    retval = KRB5_CC_FORMAT;
+	    goto done;
+	}
+	
+	while (scc_hlen) {
+	    if ((scc_hlen < (2*sizeof(krb5_ui_2))) ||
+		krb5_scc_read_ui_2(context, id, &scc_tag) ||
+		krb5_scc_read_ui_2(context, id, &scc_taglen) ||
+		(scc_taglen > (scc_hlen - 2*sizeof(krb5_ui_2))))
+	    {
+		retval = KRB5_CC_FORMAT;
+		goto done;
 	    }
-	    if ((len = (fvno_bytes[0] << 8) + fvno_bytes[1]) != 0) {
-	    	if (!fread(buf, len, 1, f)) {
-	     	    (void) krb5_unlock_file(context, fileno(f));
-	     	    (void) fclose(f);
-	     	    return KRB5_CC_FORMAT;
+
+	    switch (scc_tag) {
+	    case SCC_TAG_DELTATIME:
+		if (scc_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_scc_read(context, id, buf, scc_taglen)) {
+                         retval = KRB5_CC_FORMAT;
+                         goto done;
+                     }
+                     break;
+                 }
+                 if (krb5_scc_read_int32(context, id, &os_ctx->time_offset) ||
+                     krb5_scc_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 (scc_taglen && krb5_scc_read(context,id,buf,scc_taglen)) {
+                     retval = KRB5_CC_FORMAT;
+                     goto done;
+                 }
+                 break;
 	    }
+	    scc_hlen -= (2*sizeof(krb5_ui_2) + scc_taglen);
 	}
     }
-    data->file = f;
-    return 0;
+
+done:
+    if (retval)
+	if (f) {
+	    data->file = 0;
+	    (void) krb5_unlock_file(context, fileno(f));
+	    (void) fclose(f);
+	}
+    return retval;
 }
diff --git a/src/lib/krb5/ccache/stdio/scc_skip.c b/src/lib/krb5/ccache/stdio/scc_skip.c
index 0182402..6b072dc 100644
--- a/src/lib/krb5/ccache/stdio/scc_skip.c
+++ b/src/lib/krb5/ccache/stdio/scc_skip.c
@@ -29,6 +29,27 @@
 #include "scc.h"
 
 krb5_error_code
+krb5_scc_skip_header(context, id)
+   krb5_context context;
+   krb5_ccache id;
+{
+     krb5_error_code kret;
+     krb5_principal princ;
+     krb5_scc_data *data = (krb5_scc_data *) id->data;
+     krb5_ui_2 scc_flen;
+
+     if (fseek(data->file, sizeof(krb5_ui_2), SEEK_SET))
+	 return errno;
+     if (data->version == KRB5_SCC_FVNO_4) {
+	 kret = krb5_scc_read_ui_2(context, id, &scc_flen);
+	 if (kret) return kret;
+	 if (fseek(data->file, scc_flen, SEEK_CUR))
+	     return errno;
+     }
+     return KRB5_OK;
+}
+
+krb5_error_code
 krb5_scc_skip_principal(context, id)
    krb5_context context;
    krb5_ccache id;
@@ -43,5 +64,3 @@ krb5_scc_skip_principal(context, id)
      krb5_free_principal(context, princ);
      return KRB5_OK;
 }
-
-     
diff --git a/src/lib/krb5/ccache/stdio/scc_sseq.c b/src/lib/krb5/ccache/stdio/scc_sseq.c
index f1971c5..c5bac19 100644
--- a/src/lib/krb5/ccache/stdio/scc_sseq.c
+++ b/src/lib/krb5/ccache/stdio/scc_sseq.c
@@ -56,13 +56,16 @@ krb5_scc_start_seq_get(context, id, cursor)
 
      /* Make sure we start reading right after the primary principal */
      MAYBE_OPEN (context, id, SCC_OPEN_RDONLY);
-     /* skip over vno at beginning of file */
-     fseek(((krb5_scc_data *) id->data)->file, sizeof(krb5_int16), 0);
 
-     krb5_scc_skip_principal(context, id);
+     ret = krb5_scc_skip_header(context, id);
+     if (ret) goto done;
+     ret = krb5_scc_skip_principal(context, id);
+     if (ret) goto done;
+     
      fcursor->pos = ftell(((krb5_scc_data *) id->data)->file);
      *cursor = (krb5_cc_cursor) fcursor;
 
+done:
      MAYBE_CLOSE (context, id, ret);
      return(ret);
 }