diff --git a/libasn1parser/asn1parser.c b/libasn1parser/asn1parser.c
new file mode 100644
index 0000000..b5d9e1e
--- /dev/null
+++ b/libasn1parser/asn1parser.c
@@ -0,0 +1,171 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <assert.h>
+#include <errno.h>
+
+#include "asn1parser.h"
+#include "asn1p_list.h"
+
+int asn1p_parse(void **param);
+
+void *asn1p__scan_bytes(const char *, int len);
+void *asn1p__delete_buffer(void *);
+void *asn1p_restart(FILE *);
+
+extern int asn1p_lineno;
+
+static int _asn1p_set_flags(enum asn1p_flags flags);
+static int _asn1p_assign_filename(asn1p_t *a, const char *fname);
+
+/*
+ * Parse the given buffer.
+ */
+asn1p_t *
+asn1p_parse_buffer(const char *buffer, int size /* = -1 */, enum asn1p_flags flags) {
+	asn1p_t *a = 0;
+	void *ap;
+	void *ybuf;
+	int ret;
+
+	if(_asn1p_set_flags(flags)) {
+		/* EINVAL */
+		return 0;
+	}
+
+	if(size < 0)
+		size = strlen(buffer);
+
+	ybuf = asn1p__scan_bytes(buffer, size);
+	if(!ybuf) {
+		assert(ybuf);
+		return 0;
+	}
+
+	asn1p_lineno = 1;
+
+	ap = (void *)&a;
+	ret = asn1p_parse(ap);
+
+	asn1p__delete_buffer(ybuf);
+
+	if(ret == 0) {
+		assert(a);
+		if(_asn1p_assign_filename(a, "-"))
+			return NULL;	/* FIXME: destroy (a) */
+	} else {
+		assert(a == NULL);
+	}
+
+	return a;
+}
+
+
+/*
+ * Parse the file identified by its name.
+ */
+asn1p_t *
+asn1p_parse_file(const char *filename, enum asn1p_flags flags) {
+	struct stat sb;
+	asn1p_t *a = 0;
+	void *ap;
+	FILE *fp;
+	int ret;
+
+	if(_asn1p_set_flags(flags)) {
+		/* EINVAL */
+		return 0;
+	}
+
+	fp = fopen(filename, "r");
+	if(fp == NULL) {
+		perror(filename);
+		return NULL;
+	}
+
+	if(fstat(fileno(fp), &sb)
+	|| !S_ISREG(sb.st_mode)) {
+		fclose(fp);
+		fprintf(stderr, "%s file not recognized: Bad file format\n",
+			filename);
+		errno = EINVAL;
+		return NULL;
+	}
+
+	asn1p_lineno = 1;
+
+	asn1p_restart(fp);
+
+	ap = (void *)&a;
+	ret = asn1p_parse(ap);
+
+	fclose(fp);
+
+	if(ret == 0) {
+		assert(a);
+		if(_asn1p_assign_filename(a, filename))
+			return NULL;	/* FIXME: destroy (a) */
+	} else {
+		assert(a == NULL);
+	}
+
+	return a;
+}
+
+extern int asn1p_lexer_types_year;
+extern int asn1p_lexer_constructs_year;
+extern int asn1p__flex_debug;
+
+static int
+_asn1p_set_flags(enum asn1p_flags flags) {
+
+	asn1p_lexer_types_year = 0;
+	asn1p_lexer_constructs_year = 0;
+	asn1p__flex_debug = 0;
+
+	/*
+	 * Enable debugging in lexer.
+	 */
+	if(flags & A1P_LEXER_DEBUG) {
+		flags &= ~A1P_LEXER_DEBUG;
+		asn1p__flex_debug = 1;
+	}
+
+	/*
+	 * Restrict embedded types to ASN.1:1988 version of standard.
+	 */
+	if(flags & A1P_TYPES_RESTRICT_TO_1988) {
+		flags &= ~A1P_TYPES_RESTRICT_TO_1988;
+		asn1p_lexer_types_year = 1988;
+	}
+
+	/*
+	 * Restrict embedded types to ASN.1:1988 version of standard.
+	 */
+	if(flags & A1P_TYPES_RESTRICT_TO_1988) {
+		flags &= ~A1P_TYPES_RESTRICT_TO_1988;
+		asn1p_lexer_types_year = 1988;
+	}
+
+	/*
+	 * Check that we haven't missed an unknown flag.
+	 */
+	if(flags) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	return 0;
+}
+
+static int
+_asn1p_assign_filename(asn1p_t *a, const char *fname) {
+	asn1p_module_t *mod;
+	TQ_FOR(mod, &(a->modules), mod_next) {
+		mod->source_file_name = strdup(fname);
+		if(mod->source_file_name == NULL)
+			return -1;
+	}
+	return 0;
+}