cmd: add asn1_compiler

Imported from linux kernel v5.3:
 asn1.h without changes
 asn1_ber_bytecode.h without changes
 asn1_decoder.h without changes
 asn1_compiler.c without changes

This host command will be used to create a ASN1 parser, for example,
for pkcs7 messages or x509 certificates. More specifically, it will
generate *byte code* which will be interpreted by asn1 decoder library.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

3 files changed, 174 insertions, 0 deletions

diff --git a/include/linux/asn1.h b/include/linux/asn1.h
new file mode 100644
index 0000000000..a4d0bdd107
--- /dev/null
+++ b/include/linux/asn1.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* ASN.1 BER/DER/CER encoding definitions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _LINUX_ASN1_H
+#define _LINUX_ASN1_H
+
+/* Class */
+enum asn1_class {
+	ASN1_UNIV	= 0,	/* Universal */
+	ASN1_APPL	= 1,	/* Application */
+	ASN1_CONT	= 2,	/* Context */
+	ASN1_PRIV	= 3	/* Private */
+};
+#define ASN1_CLASS_BITS	0xc0
+
+
+enum asn1_method {
+	ASN1_PRIM	= 0,	/* Primitive */
+	ASN1_CONS	= 1	/* Constructed */
+};
+#define ASN1_CONS_BIT	0x20
+
+/* Tag */
+enum asn1_tag {
+	ASN1_EOC	= 0,	/* End Of Contents or N/A */
+	ASN1_BOOL	= 1,	/* Boolean */
+	ASN1_INT	= 2,	/* Integer */
+	ASN1_BTS	= 3,	/* Bit String */
+	ASN1_OTS	= 4,	/* Octet String */
+	ASN1_NULL	= 5,	/* Null */
+	ASN1_OID	= 6,	/* Object Identifier  */
+	ASN1_ODE	= 7,	/* Object Description */
+	ASN1_EXT	= 8,	/* External */
+	ASN1_REAL	= 9,	/* Real float */
+	ASN1_ENUM	= 10,	/* Enumerated */
+	ASN1_EPDV	= 11,	/* Embedded PDV */
+	ASN1_UTF8STR	= 12,	/* UTF8 String */
+	ASN1_RELOID	= 13,	/* Relative OID */
+	/* 14 - Reserved */
+	/* 15 - Reserved */
+	ASN1_SEQ	= 16,	/* Sequence and Sequence of */
+	ASN1_SET	= 17,	/* Set and Set of */
+	ASN1_NUMSTR	= 18,	/* Numerical String */
+	ASN1_PRNSTR	= 19,	/* Printable String */
+	ASN1_TEXSTR	= 20,	/* T61 String / Teletext String */
+	ASN1_VIDSTR	= 21,	/* Videotex String */
+	ASN1_IA5STR	= 22,	/* IA5 String */
+	ASN1_UNITIM	= 23,	/* Universal Time */
+	ASN1_GENTIM	= 24,	/* General Time */
+	ASN1_GRASTR	= 25,	/* Graphic String */
+	ASN1_VISSTR	= 26,	/* Visible String */
+	ASN1_GENSTR	= 27,	/* General String */
+	ASN1_UNISTR	= 28,	/* Universal String */
+	ASN1_CHRSTR	= 29,	/* Character String */
+	ASN1_BMPSTR	= 30,	/* BMP String */
+	ASN1_LONG_TAG	= 31	/* Long form tag */
+};
+
+#define ASN1_INDEFINITE_LENGTH 0x80
+
+#endif /* _LINUX_ASN1_H */
diff --git a/include/linux/asn1_ber_bytecode.h b/include/linux/asn1_ber_bytecode.h
new file mode 100644
index 0000000000..b38361953a
--- /dev/null
+++ b/include/linux/asn1_ber_bytecode.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* ASN.1 BER/DER/CER parsing state machine internal definitions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _LINUX_ASN1_BER_BYTECODE_H
+#define _LINUX_ASN1_BER_BYTECODE_H
+
+#ifdef __KERNEL__
+#include <linux/types.h>
+#endif
+#include <linux/asn1.h>
+
+typedef int (*asn1_action_t)(void *context,
+			     size_t hdrlen, /* In case of ANY type */
+			     unsigned char tag, /* In case of ANY type */
+			     const void *value, size_t vlen);
+
+struct asn1_decoder {
+	const unsigned char *machine;
+	size_t machlen;
+	const asn1_action_t *actions;
+};
+
+enum asn1_opcode {
+	/* The tag-matching ops come first and the odd-numbered slots
+	 * are for OR_SKIP ops.
+	 */
+#define ASN1_OP_MATCH__SKIP		  0x01
+#define ASN1_OP_MATCH__ACT		  0x02
+#define ASN1_OP_MATCH__JUMP		  0x04
+#define ASN1_OP_MATCH__ANY		  0x08
+#define ASN1_OP_MATCH__COND		  0x10
+
+	ASN1_OP_MATCH			= 0x00,
+	ASN1_OP_MATCH_OR_SKIP		= 0x01,
+	ASN1_OP_MATCH_ACT		= 0x02,
+	ASN1_OP_MATCH_ACT_OR_SKIP	= 0x03,
+	ASN1_OP_MATCH_JUMP		= 0x04,
+	ASN1_OP_MATCH_JUMP_OR_SKIP	= 0x05,
+	ASN1_OP_MATCH_ANY		= 0x08,
+	ASN1_OP_MATCH_ANY_OR_SKIP	= 0x09,
+	ASN1_OP_MATCH_ANY_ACT		= 0x0a,
+	ASN1_OP_MATCH_ANY_ACT_OR_SKIP	= 0x0b,
+	/* Everything before here matches unconditionally */
+
+	ASN1_OP_COND_MATCH_OR_SKIP	= 0x11,
+	ASN1_OP_COND_MATCH_ACT_OR_SKIP	= 0x13,
+	ASN1_OP_COND_MATCH_JUMP_OR_SKIP	= 0x15,
+	ASN1_OP_COND_MATCH_ANY		= 0x18,
+	ASN1_OP_COND_MATCH_ANY_OR_SKIP	= 0x19,
+	ASN1_OP_COND_MATCH_ANY_ACT	= 0x1a,
+	ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP = 0x1b,
+
+	/* Everything before here will want a tag from the data */
+#define ASN1_OP__MATCHES_TAG ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP
+
+	/* These are here to help fill up space */
+	ASN1_OP_COND_FAIL		= 0x1c,
+	ASN1_OP_COMPLETE		= 0x1d,
+	ASN1_OP_ACT			= 0x1e,
+	ASN1_OP_MAYBE_ACT		= 0x1f,
+
+	/* The following eight have bit 0 -> SET, 1 -> OF, 2 -> ACT */
+	ASN1_OP_END_SEQ			= 0x20,
+	ASN1_OP_END_SET			= 0x21,
+	ASN1_OP_END_SEQ_OF		= 0x22,
+	ASN1_OP_END_SET_OF		= 0x23,
+	ASN1_OP_END_SEQ_ACT		= 0x24,
+	ASN1_OP_END_SET_ACT		= 0x25,
+	ASN1_OP_END_SEQ_OF_ACT		= 0x26,
+	ASN1_OP_END_SET_OF_ACT		= 0x27,
+#define ASN1_OP_END__SET		  0x01
+#define ASN1_OP_END__OF			  0x02
+#define ASN1_OP_END__ACT		  0x04
+
+	ASN1_OP_RETURN			= 0x28,
+
+	ASN1_OP__NR
+};
+
+#define _tag(CLASS, CP, TAG) ((ASN1_##CLASS << 6) | (ASN1_##CP << 5) | ASN1_##TAG)
+#define _tagn(CLASS, CP, TAG) ((ASN1_##CLASS << 6) | (ASN1_##CP << 5) | TAG)
+#define _jump_target(N) (N)
+#define _action(N) (N)
+
+#endif /* _LINUX_ASN1_BER_BYTECODE_H */
diff --git a/include/linux/asn1_decoder.h b/include/linux/asn1_decoder.h
new file mode 100644
index 0000000000..83f9c6e1e5
--- /dev/null
+++ b/include/linux/asn1_decoder.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* ASN.1 decoder
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _LINUX_ASN1_DECODER_H
+#define _LINUX_ASN1_DECODER_H
+
+#include <linux/asn1.h>
+
+struct asn1_decoder;
+
+extern int asn1_ber_decoder(const struct asn1_decoder *decoder,
+			    void *context,
+			    const unsigned char *data,
+			    size_t datalen);
+
+#endif /* _LINUX_ASN1_DECODER_H */