--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nss/lib/util/derenc.c	Mon Jul 28 10:47:06 2014 +0200
@@ -0,0 +1,473 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "secder.h"
+#include "secerr.h"
+
+#if 0
+/*
+ * Generic templates for individual/simple items.
+ */
+
+DERTemplate SECAnyTemplate[] = {
+    { DER_ANY,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECBitStringTemplate[] = {
+    { DER_BIT_STRING,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECBooleanTemplate[] = {
+    { DER_BOOLEAN,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECIA5StringTemplate[] = {
+    { DER_IA5_STRING,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECIntegerTemplate[] = {
+    { DER_INTEGER,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECNullTemplate[] = {
+    { DER_NULL,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECObjectIDTemplate[] = {
+    { DER_OBJECT_ID,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECOctetStringTemplate[] = {
+    { DER_OCTET_STRING,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECPrintableStringTemplate[] = {
+    { DER_PRINTABLE_STRING,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECT61StringTemplate[] = {
+    { DER_T61_STRING,
+	  0, NULL, sizeof(SECItem) }
+};
+
+DERTemplate SECUTCTimeTemplate[] = {
+    { DER_UTC_TIME,
+	  0, NULL, sizeof(SECItem) }
+};
+
+#endif
+
+static int
+header_length(DERTemplate *dtemplate, PRUint32 contents_len)
+{
+    PRUint32 len;
+    unsigned long encode_kind, under_kind;
+    PRBool explicit, optional, universal;
+
+    encode_kind = dtemplate->kind;
+
+    explicit = (encode_kind & DER_EXPLICIT) ? PR_TRUE : PR_FALSE;
+    optional = (encode_kind & DER_OPTIONAL) ? PR_TRUE : PR_FALSE;
+    universal = ((encode_kind & DER_CLASS_MASK) == DER_UNIVERSAL)
+		? PR_TRUE : PR_FALSE;
+
+    PORT_Assert (!(explicit && universal));	/* bad templates */
+
+    if (encode_kind & DER_POINTER) {
+	if (dtemplate->sub != NULL) {
+	    under_kind = dtemplate->sub->kind;
+	    if (universal) {
+		encode_kind = under_kind;
+	    }
+	} else if (universal) {
+	    under_kind = encode_kind & ~DER_POINTER;
+	} else {
+	    under_kind = dtemplate->arg;
+	}
+    } else if (encode_kind & DER_INLINE) {
+	PORT_Assert (dtemplate->sub != NULL);
+	under_kind = dtemplate->sub->kind;
+	if (universal) {
+	    encode_kind = under_kind;
+	}
+    } else if (universal) {
+	under_kind = encode_kind;
+    } else {
+	under_kind = dtemplate->arg;
+    }
+
+    /* This is only used in decoding; it plays no part in encoding.  */
+    if (under_kind & DER_DERPTR)
+	return 0;
+
+    /* No header at all for an "empty" optional.  */
+    if ((contents_len == 0) && optional)
+	return 0;
+
+    /* And no header for a full DER_ANY.  */
+    if (encode_kind & DER_ANY)
+	return 0;
+
+    /*
+     * The common case: one octet for identifier and as many octets
+     * as necessary to hold the content length.
+     */
+    len = 1 + DER_LengthLength(contents_len);
+
+    /* Account for the explicit wrapper, if necessary.  */
+    if (explicit) {
+#if 0		/*
+		 * Well, I was trying to do something useful, but these
+		 * assertions are too restrictive on valid templates.
+		 * I wanted to make sure that the top-level "kind" of
+		 * a template does not also specify DER_EXPLICIT, which
+		 * should only modify a component field.  Maybe later
+		 * I can figure out a better way to detect such a problem,
+		 * but for now I must remove these checks altogether.
+		 */
+	/*
+	 * This modifier applies only to components of a set or sequence;
+	 * it should never be used on a set/sequence itself -- confirm.
+	 */
+	PORT_Assert (under_kind != DER_SEQUENCE);
+	PORT_Assert (under_kind != DER_SET);
+#endif
+
+	len += 1 + DER_LengthLength(len + contents_len);
+    }
+
+    return len;
+}
+
+
+static PRUint32
+contents_length(DERTemplate *dtemplate, void *src)
+{
+    PRUint32 len;
+    unsigned long encode_kind, under_kind;
+    PRBool universal;
+
+
+    PORT_Assert (src != NULL);
+
+    encode_kind = dtemplate->kind;
+
+    universal = ((encode_kind & DER_CLASS_MASK) == DER_UNIVERSAL)
+		? PR_TRUE : PR_FALSE;
+    encode_kind &= ~DER_OPTIONAL;
+
+    if (encode_kind & DER_POINTER) {
+	src = *(void **)src;
+	if (src == NULL) {
+	    return 0;
+	}
+	if (dtemplate->sub != NULL) {
+	    dtemplate = dtemplate->sub;
+	    under_kind = dtemplate->kind;
+	    src = (void *)((char *)src + dtemplate->offset);
+	} else if (universal) {
+	    under_kind = encode_kind & ~DER_POINTER;
+	} else {
+	    under_kind = dtemplate->arg;
+	}
+    } else if (encode_kind & DER_INLINE) {
+	PORT_Assert (dtemplate->sub != NULL);
+	dtemplate = dtemplate->sub;
+	under_kind = dtemplate->kind;
+	src = (void *)((char *)src + dtemplate->offset);
+    } else if (universal) {
+	under_kind = encode_kind;
+    } else {
+	under_kind = dtemplate->arg;
+    }
+
+    /* Having any of these bits is not expected here...  */
+    PORT_Assert ((under_kind & (DER_EXPLICIT | DER_INLINE | DER_OPTIONAL
+				| DER_POINTER | DER_SKIP)) == 0);
+
+    /* This is only used in decoding; it plays no part in encoding.  */
+    if (under_kind & DER_DERPTR)
+	return 0;
+
+    if (under_kind & DER_INDEFINITE) {
+	PRUint32 sub_len;
+	void   **indp = *(void ***)src;
+
+	if (indp == NULL)
+	    return 0;
+
+	len = 0;
+	under_kind &= ~DER_INDEFINITE;
+
+	if (under_kind == DER_SET || under_kind == DER_SEQUENCE) {
+	    DERTemplate *tmpt = dtemplate->sub;
+	    PORT_Assert (tmpt != NULL);
+
+	    for (; *indp != NULL; indp++) {
+		void *sub_src = (void *)((char *)(*indp) + tmpt->offset);
+		sub_len = contents_length (tmpt, sub_src);
+		len += sub_len + header_length (tmpt, sub_len);
+	    }
+	} else {
+	    /*
+	     * XXX Lisa is not sure this code (for handling, for example,
+	     * DER_INDEFINITE | DER_OCTET_STRING) is right.
+	     */
+	    for (; *indp != NULL; indp++) {
+		SECItem *item = (SECItem *)(*indp);
+		sub_len = item->len;
+		if (under_kind == DER_BIT_STRING) {
+		    sub_len = (sub_len + 7) >> 3;
+		    /* bit string contents involve an extra octet */
+		    if (sub_len)
+			sub_len++;
+		}
+		if (under_kind != DER_ANY)
+		    len += 1 + DER_LengthLength (sub_len);
+	    }
+	}
+
+	return len;
+    }
+
+    switch (under_kind) {
+      case DER_SEQUENCE:
+      case DER_SET:
+	{
+	    DERTemplate *tmpt;
+	    void *sub_src;
+	    PRUint32 sub_len;
+
+	    len = 0;
+	    for (tmpt = dtemplate + 1; tmpt->kind; tmpt++) {
+		sub_src = (void *)((char *)src + tmpt->offset);
+		sub_len = contents_length (tmpt, sub_src);
+		len += sub_len + header_length (tmpt, sub_len);
+	    }
+	}
+	break;
+
+      case DER_BIT_STRING:
+	len = (((SECItem *)src)->len + 7) >> 3;
+	/* bit string contents involve an extra octet */
+	if (len)
+	    len++;
+	break;
+
+      default:
+	len = ((SECItem *)src)->len;
+	break;
+    }
+
+    return len;
+}
+
+
+static unsigned char *
+der_encode(unsigned char *buf, DERTemplate *dtemplate, void *src)
+{
+    int header_len;
+    PRUint32 contents_len;
+    unsigned long encode_kind, under_kind;
+    PRBool explicit, optional, universal;
+
+
+    /*
+     * First figure out how long the encoding will be.  Do this by
+     * traversing the template from top to bottom and accumulating
+     * the length of each leaf item.
+     */
+    contents_len = contents_length (dtemplate, src);
+    header_len = header_length (dtemplate, contents_len);
+
+    /*
+     * Enough smarts was involved already, so that if both the
+     * header and the contents have a length of zero, then we
+     * are not doing any encoding for this element.
+     */
+    if (header_len == 0 && contents_len == 0)
+	return buf;
+
+    encode_kind = dtemplate->kind;
+
+    explicit = (encode_kind & DER_EXPLICIT) ? PR_TRUE : PR_FALSE;
+    optional = (encode_kind & DER_OPTIONAL) ? PR_TRUE : PR_FALSE;
+    encode_kind &= ~DER_OPTIONAL;
+    universal = ((encode_kind & DER_CLASS_MASK) == DER_UNIVERSAL)
+		? PR_TRUE : PR_FALSE;
+
+    if (encode_kind & DER_POINTER) {
+	if (contents_len) {
+	    src = *(void **)src;
+	    PORT_Assert (src != NULL);
+	}
+	if (dtemplate->sub != NULL) {
+	    dtemplate = dtemplate->sub;
+	    under_kind = dtemplate->kind;
+	    if (universal) {
+		encode_kind = under_kind;
+	    }
+	    src = (void *)((char *)src + dtemplate->offset);
+	} else if (universal) {
+	    under_kind = encode_kind & ~DER_POINTER;
+	} else {
+	    under_kind = dtemplate->arg;
+	}
+    } else if (encode_kind & DER_INLINE) {
+	dtemplate = dtemplate->sub;
+	under_kind = dtemplate->kind;
+	if (universal) {
+	    encode_kind = under_kind;
+	}
+	src = (void *)((char *)src + dtemplate->offset);
+    } else if (universal) {
+	under_kind = encode_kind;
+    } else {
+	under_kind = dtemplate->arg;
+    }
+
+    if (explicit) {
+	buf = DER_StoreHeader (buf, encode_kind,
+			       (1 + DER_LengthLength(contents_len)
+				+ contents_len));
+	encode_kind = under_kind;
+    }
+
+    if ((encode_kind & DER_ANY) == 0) {	/* DER_ANY already contains header */
+	buf = DER_StoreHeader (buf, encode_kind, contents_len);
+    }
+
+    /* If no real contents to encode, then we are done.  */
+    if (contents_len == 0)
+	return buf;
+
+    if (under_kind & DER_INDEFINITE) {
+	void **indp;
+
+	indp = *(void ***)src;
+	PORT_Assert (indp != NULL);
+
+	under_kind &= ~DER_INDEFINITE;
+	if (under_kind == DER_SET || under_kind == DER_SEQUENCE) {
+	    DERTemplate *tmpt = dtemplate->sub;
+	    PORT_Assert (tmpt != NULL);
+	    for (; *indp != NULL; indp++) {
+		void *sub_src = (void *)((char *)(*indp) + tmpt->offset);
+		buf = der_encode (buf, tmpt, sub_src);
+	    }
+	} else {
+	    for (; *indp != NULL; indp++) {
+		SECItem *item;
+		int sub_len;
+
+		item = (SECItem *)(*indp);
+		sub_len = item->len;
+		if (under_kind == DER_BIT_STRING) {
+		    if (sub_len) {
+			int rem;
+
+			sub_len = (sub_len + 7) >> 3;
+			buf = DER_StoreHeader (buf, under_kind, sub_len + 1);
+			rem = (sub_len << 3) - item->len;
+			*buf++ = rem;		/* remaining bits */
+		    } else {
+			buf = DER_StoreHeader (buf, under_kind, 0);
+		    }
+		} else if (under_kind != DER_ANY) {
+		    buf = DER_StoreHeader (buf, under_kind, sub_len);
+		}
+		PORT_Memcpy (buf, item->data, sub_len);
+		buf += sub_len;
+	    }
+	}
+	return buf;
+    }
+
+    switch (under_kind) {
+      case DER_SEQUENCE:
+      case DER_SET:
+	{
+	    DERTemplate *tmpt;
+	    void *sub_src;
+
+	    for (tmpt = dtemplate + 1; tmpt->kind; tmpt++) {
+		sub_src = (void *)((char *)src + tmpt->offset);
+		buf = der_encode (buf, tmpt, sub_src);
+	    }
+	}
+	break;
+
+      case DER_BIT_STRING:
+	{
+	    SECItem *item;
+	    int rem;
+
+	    /*
+	     * The contents length includes our extra octet; subtract
+	     * it off so we just have the real string length there.
+	     */
+	    contents_len--;
+	    item = (SECItem *)src;
+	    PORT_Assert (contents_len == ((item->len + 7) >> 3));
+	    rem = (contents_len << 3) - item->len;
+	    *buf++ = rem;		/* remaining bits */
+	    PORT_Memcpy (buf, item->data, contents_len);
+	    buf += contents_len;
+	}
+	break;
+
+      default:
+	{
+	    SECItem *item;
+
+	    item = (SECItem *)src;
+	    PORT_Assert (contents_len == item->len);
+	    PORT_Memcpy (buf, item->data, contents_len);
+	    buf += contents_len;
+	}
+	break;
+    }
+
+    return buf;
+}
+
+
+SECStatus
+DER_Encode(PLArenaPool *arena, SECItem *dest, DERTemplate *dtemplate, void *src)
+{
+    unsigned int contents_len, header_len;
+
+    src = (void **)((char *)src + dtemplate->offset);
+
+    /*
+     * First figure out how long the encoding will be. Do this by
+     * traversing the template from top to bottom and accumulating
+     * the length of each leaf item.
+     */
+    contents_len = contents_length (dtemplate, src);
+    header_len = header_length (dtemplate, contents_len);
+
+    dest->len = contents_len + header_len;
+
+    /* Allocate storage to hold the encoding */
+    dest->data = (unsigned char*) PORT_ArenaAlloc(arena, dest->len);
+    if (dest->data == NULL) {
+	PORT_SetError(SEC_ERROR_NO_MEMORY);
+	return SECFailure;
+    }
+
+    /* Now encode into the buffer */
+    (void) der_encode (dest->data, dtemplate, src);
+
+    return SECSuccess;
+}