Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1176 insertions, 0 deletions

diff --git a/lib/util/asn1.c b/lib/util/asn1.c
new file mode 100644
index 0000000..1a92a55
--- /dev/null
+++ b/lib/util/asn1.c
@@ -0,0 +1,1176 @@
+/*
+   Unix SMB/CIFS implementation.
+   simple ASN1 routines
+   Copyright (C) Andrew Tridgell 2001
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "replace.h"
+#include "system/locale.h"
+#include "lib/util/asn1.h"
+#include "lib/util/debug.h"
+#include "lib/util/samba_util.h"
+#include "lib/util/smb_strtox.h"
+
+struct nesting {
+	off_t start;
+	size_t taglen; /* for parsing */
+	struct nesting *next;
+};
+
+
+struct asn1_data {
+	uint8_t *data;
+	size_t length;
+	off_t ofs;
+	struct nesting *nesting;
+	bool has_error;
+	unsigned depth;
+	unsigned max_depth;
+};
+
+/* allocate an asn1 structure */
+struct asn1_data *asn1_init(TALLOC_CTX *mem_ctx, unsigned max_depth)
+{
+	struct asn1_data *ret = talloc_zero(mem_ctx, struct asn1_data);
+	if (ret == NULL) {
+		DBG_ERR("asn1_init failed! out of memory\n");
+		return ret;
+	}
+	ret->max_depth = max_depth;
+	return ret;
+}
+
+/* free an asn1 structure */
+void asn1_free(struct asn1_data *data)
+{
+	talloc_free(data);
+}
+
+bool asn1_has_error(const struct asn1_data *data)
+{
+	return data->has_error;
+}
+
+void asn1_set_error(struct asn1_data *data)
+{
+	data->has_error = true;
+}
+
+bool asn1_has_nesting(const struct asn1_data *data)
+{
+	return data->nesting != NULL;
+}
+
+off_t asn1_current_ofs(const struct asn1_data *data)
+{
+	return data->ofs;
+}
+
+/* write to the ASN1 buffer, advancing the buffer pointer */
+bool asn1_write(struct asn1_data *data, const void *p, int len)
+{
+	if (data->has_error) return false;
+
+	if ((len < 0) || (data->ofs + (size_t)len < data->ofs)) {
+		data->has_error = true;
+		return false;
+	}
+
+	if (data->length < data->ofs+len) {
+		uint8_t *newp;
+		newp = talloc_realloc(data, data->data, uint8_t, data->ofs+len);
+		if (!newp) {
+			data->has_error = true;
+			return false;
+		}
+		data->data = newp;
+		data->length = data->ofs+len;
+	}
+	if (len > 0) {
+		memcpy(data->data + data->ofs, p, len);
+		data->ofs += len;
+	}
+	return true;
+}
+
+/* useful fn for writing a uint8_t */
+bool asn1_write_uint8(struct asn1_data *data, uint8_t v)
+{
+	return asn1_write(data, &v, 1);
+}
+
+/* push a tag onto the asn1 data buffer. Used for nested structures */
+bool asn1_push_tag(struct asn1_data *data, uint8_t tag)
+{
+	struct nesting *nesting;
+
+	if (!asn1_write_uint8(data, tag)) {
+		return false;
+	}
+	nesting = talloc(data, struct nesting);
+	if (!nesting) {
+		data->has_error = true;
+		return false;
+	}
+
+	nesting->start = data->ofs;
+	nesting->next = data->nesting;
+	data->nesting = nesting;
+	return asn1_write_uint8(data, 0xff);
+}
+
+/* pop a tag */
+bool asn1_pop_tag(struct asn1_data *data)
+{
+	struct nesting *nesting;
+	size_t len;
+
+	if (data->has_error) {
+		return false;
+	}
+
+	nesting = data->nesting;
+
+	if (!nesting) {
+		data->has_error = true;
+		return false;
+	}
+	len = data->ofs - (nesting->start+1);
+	/* yes, this is ugly. We don't know in advance how many bytes the length
+	   of a tag will take, so we assumed 1 byte. If we were wrong then we
+	   need to correct our mistake */
+	if (len > 0xFFFFFF) {
+		data->data[nesting->start] = 0x84;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		memmove(data->data+nesting->start+5, data->data+nesting->start+1, len);
+		data->data[nesting->start+1] = (len>>24) & 0xFF;
+		data->data[nesting->start+2] = (len>>16) & 0xFF;
+		data->data[nesting->start+3] = (len>>8) & 0xFF;
+		data->data[nesting->start+4] = len&0xff;
+	} else if (len > 0xFFFF) {
+		data->data[nesting->start] = 0x83;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		memmove(data->data+nesting->start+4, data->data+nesting->start+1, len);
+		data->data[nesting->start+1] = (len>>16) & 0xFF;
+		data->data[nesting->start+2] = (len>>8) & 0xFF;
+		data->data[nesting->start+3] = len&0xff;
+	} else if (len > 255) {
+		data->data[nesting->start] = 0x82;
+		if (!asn1_write_uint8(data, 0)) return false;
+		if (!asn1_write_uint8(data, 0)) return false;
+		memmove(data->data+nesting->start+3, data->data+nesting->start+1, len);
+		data->data[nesting->start+1] = len>>8;
+		data->data[nesting->start+2] = len&0xff;
+	} else if (len > 127) {
+		data->data[nesting->start] = 0x81;
+		if (!asn1_write_uint8(data, 0)) return false;
+		memmove(data->data+nesting->start+2, data->data+nesting->start+1, len);
+		data->data[nesting->start+1] = len;
+	} else {
+		data->data[nesting->start] = len;
+	}
+
+	data->nesting = nesting->next;
+	talloc_free(nesting);
+	return true;
+}
+
+/* "i" is the one's complement representation, as is the normal result of an
+ * implicit signed->unsigned conversion */
+
+static bool push_int_bigendian(struct asn1_data *data, unsigned int i, bool negative)
+{
+	uint8_t lowest = i & 0xFF;
+
+	i = i >> 8;
+	if (i != 0)
+		if (!push_int_bigendian(data, i, negative))
+			return false;
+
+	if (data->nesting->start+1 == data->ofs) {
+
+		/* We did not write anything yet, looking at the highest
+		 * valued byte */
+
+		if (negative) {
+			/* Don't write leading 0xff's */
+			if (lowest == 0xFF)
+				return true;
+
+			if ((lowest & 0x80) == 0) {
+				/* The only exception for a leading 0xff is if
+				 * the highest bit is 0, which would indicate
+				 * a positive value */
+				if (!asn1_write_uint8(data, 0xff))
+					return false;
+			}
+		} else {
+			if (lowest & 0x80) {
+				/* The highest bit of a positive integer is 1,
+				 * this would indicate a negative number. Push
+				 * a 0 to indicate a positive one */
+				if (!asn1_write_uint8(data, 0))
+					return false;
+			}
+		}
+	}
+
+	return asn1_write_uint8(data, lowest);
+}
+
+/* write an Integer without the tag framing. Needed for example for the LDAP
+ * Abandon Operation */
+
+bool asn1_write_implicit_Integer(struct asn1_data *data, int i)
+{
+	if (data->has_error) {
+		return false;
+	}
+
+	if (i == -1) {
+		/* -1 is special as it consists of all-0xff bytes. In
+                    push_int_bigendian this is the only case that is not
+                    properly handled, as all 0xff bytes would be handled as
+                    leading ones to be ignored. */
+		return asn1_write_uint8(data, 0xff);
+	} else {
+		return push_int_bigendian(data, i, i<0);
+	}
+}
+
+
+/* write an integer */
+bool asn1_write_Integer(struct asn1_data *data, int i)
+{
+	if (!asn1_push_tag(data, ASN1_INTEGER)) return false;
+	if (!asn1_write_implicit_Integer(data, i)) return false;
+	return asn1_pop_tag(data);
+}
+
+/* write a BIT STRING */
+bool asn1_write_BitString(struct asn1_data *data, const void *p, size_t length, uint8_t padding)
+{
+	if (!asn1_push_tag(data, ASN1_BIT_STRING)) return false;
+	if (!asn1_write_uint8(data, padding)) return false;
+	if (!asn1_write(data, p, length)) return false;
+	return asn1_pop_tag(data);
+}
+
+bool ber_write_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, const char *OID)
+{
+	unsigned int v, v2;
+	const char *p = (const char *)OID;
+	char *newp;
+	int i;
+	int error = 0;
+
+	if (!isdigit(*p)) return false;
+	v = smb_strtoul(p, &newp, 10, &error, SMB_STR_STANDARD);
+	if (newp[0] != '.' || error != 0) {
+		return false;
+	}
+	p = newp + 1;
+
+	if (!isdigit(*p)) return false;
+	v2 = smb_strtoul(p, &newp, 10, &error, SMB_STR_STANDARD);
+	if (newp[0] != '.' || error != 0) {
+		return false;
+	}
+	p = newp + 1;
+
+	/*the ber representation can't use more space than the string one */
+	*blob = data_blob_talloc(mem_ctx, NULL, strlen(OID));
+	if (!blob->data) return false;
+
+	blob->data[0] = 40*v + v2;
+
+	i = 1;
+	while (*p) {
+		if (!isdigit(*p)) return false;
+		v = smb_strtoul(p, &newp, 10, &error, SMB_STR_STANDARD);
+		if (newp[0] == '.' || error != 0) {
+			p = newp + 1;
+			/* check for empty last component */
+			if (!*p) return false;
+		} else if (newp[0] == '\0') {
+			p = newp;
+		} else {
+			data_blob_free(blob);
+			return false;
+		}
+		if (v >= (1<<28)) blob->data[i++] = (0x80 | ((v>>28)&0x7f));
+		if (v >= (1<<21)) blob->data[i++] = (0x80 | ((v>>21)&0x7f));
+		if (v >= (1<<14)) blob->data[i++] = (0x80 | ((v>>14)&0x7f));
+		if (v >= (1<<7)) blob->data[i++] = (0x80 | ((v>>7)&0x7f));
+		blob->data[i++] = (v&0x7f);
+	}
+
+	blob->length = i;
+
+	return true;
+}
+
+/**
+ * Serialize partial OID string.
+ * Partial OIDs are in the form:
+ *   1:2.5.6:0x81
+ *   1:2.5.6:0x8182
+ */
+bool ber_write_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, const char *partial_oid)
+{
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	char *oid = talloc_strdup(tmp_ctx, partial_oid);
+	char *p;
+
+	/* truncate partial part so ber_write_OID_String() works */
+	p = strchr(oid, ':');
+	if (p) {
+		*p = '\0';
+		p++;
+	}
+
+	if (!ber_write_OID_String(mem_ctx, blob, oid)) {
+		talloc_free(tmp_ctx);
+		return false;
+	}
+
+	/* Add partially encoded sub-identifier */
+	if (p) {
+		DATA_BLOB tmp_blob = strhex_to_data_blob(tmp_ctx, p);
+		if (!data_blob_append(mem_ctx, blob, tmp_blob.data,
+				      tmp_blob.length)) {
+			talloc_free(tmp_ctx);
+			return false;
+		}
+	}
+
+	talloc_free(tmp_ctx);
+
+	return true;
+}
+
+/* write an object ID to a ASN1 buffer */
+bool asn1_write_OID(struct asn1_data *data, const char *OID)
+{
+	DATA_BLOB blob;
+
+	if (!asn1_push_tag(data, ASN1_OID)) return false;
+
+	if (!ber_write_OID_String(NULL, &blob, OID)) {
+		data->has_error = true;
+		return false;
+	}
+
+	if (!asn1_write(data, blob.data, blob.length)) {
+		data_blob_free(&blob);
+		data->has_error = true;
+		return false;
+	}
+	data_blob_free(&blob);
+	return asn1_pop_tag(data);
+}
+
+/* write an octet string */
+bool asn1_write_OctetString(struct asn1_data *data, const void *p, size_t length)
+{
+	if (!asn1_push_tag(data, ASN1_OCTET_STRING)) return false;
+	if (!asn1_write(data, p, length)) return false;
+	return asn1_pop_tag(data);
+}
+
+/* write a LDAP string */
+bool asn1_write_LDAPString(struct asn1_data *data, const char *s)
+{
+	return asn1_write(data, s, strlen(s));
+}
+
+/* write a LDAP string from a DATA_BLOB */
+bool asn1_write_DATA_BLOB_LDAPString(struct asn1_data *data, const DATA_BLOB *s)
+{
+	return asn1_write(data, s->data, s->length);
+}
+
+/* write a general string */
+bool asn1_write_GeneralString(struct asn1_data *data, const char *s)
+{
+	if (!asn1_push_tag(data, ASN1_GENERAL_STRING)) return false;
+	if (!asn1_write_LDAPString(data, s)) return false;
+	return asn1_pop_tag(data);
+}
+
+bool asn1_write_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
+{
+	if (!asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(num))) return false;
+	if (!asn1_write(data, blob->data, blob->length)) return false;
+	return asn1_pop_tag(data);
+}
+
+/* write a BOOLEAN */
+bool asn1_write_BOOLEAN(struct asn1_data *data, bool v)
+{
+	if (!asn1_push_tag(data, ASN1_BOOLEAN)) return false;
+	if (!asn1_write_uint8(data, v ? 0xFF : 0)) return false;
+	return asn1_pop_tag(data);
+}
+
+bool asn1_read_BOOLEAN(struct asn1_data *data, bool *v)
+{
+	uint8_t tmp = 0;
+	if (!asn1_start_tag(data, ASN1_BOOLEAN)) return false;
+	*v = false;
+	if (!asn1_read_uint8(data, &tmp)) return false;
+	if (tmp == 0xFF) {
+		*v = true;
+	}
+	return asn1_end_tag(data);
+}
+
+/* write a BOOLEAN in a simple context */
+bool asn1_write_BOOLEAN_context(struct asn1_data *data, bool v, int context)
+{
+	if (!asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(context))) return false;
+	if (!asn1_write_uint8(data, v ? 0xFF : 0)) return false;
+	return asn1_pop_tag(data);
+}
+
+bool asn1_read_BOOLEAN_context(struct asn1_data *data, bool *v, int context)
+{
+	uint8_t tmp = 0;
+	if (!asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(context))) return false;
+	*v = false;
+	if (!asn1_read_uint8(data, &tmp)) return false;
+	if (tmp == 0xFF) {
+		*v = true;
+	}
+	return asn1_end_tag(data);
+}
+
+/* check a BOOLEAN */
+bool asn1_check_BOOLEAN(struct asn1_data *data, bool v)
+{
+	uint8_t b = 0;
+
+	if (!asn1_read_uint8(data, &b)) return false;
+	if (b != ASN1_BOOLEAN) {
+		data->has_error = true;
+		return false;
+	}
+	if (!asn1_read_uint8(data, &b)) return false;
+	if (b != v) {
+		data->has_error = true;
+		return false;
+	}
+	return !data->has_error;
+}
+
+
+/* load a struct asn1_data structure with a lump of data, ready to be parsed */
+bool asn1_load(struct asn1_data *data, DATA_BLOB blob)
+{
+	/*
+	 * Save the maximum depth
+	 */
+	unsigned max_depth = data->max_depth;
+
+	ZERO_STRUCTP(data);
+	data->data = (uint8_t *)talloc_memdup(data, blob.data, blob.length);
+	if (!data->data) {
+		data->has_error = true;
+		return false;
+	}
+	data->length = blob.length;
+	data->max_depth = max_depth;
+	return true;
+}
+
+/* Peek into an ASN1 buffer, not advancing the pointer */
+bool asn1_peek(struct asn1_data *data, void *p, int len)
+{
+	if (data->has_error)
+		return false;
+
+	if (len < 0 || data->ofs + len < data->ofs || data->ofs + len < len)
+		return false;
+
+	if (data->ofs + len > data->length) {
+		/* we need to mark the buffer as consumed, so the caller knows
+		   this was an out of data error, and not a decode error */
+		data->ofs = data->length;
+		return false;
+	}
+
+	memcpy(p, data->data + data->ofs, len);
+	return true;
+}
+
+/* read from a ASN1 buffer, advancing the buffer pointer */
+bool asn1_read(struct asn1_data *data, void *p, int len)
+{
+	if (!asn1_peek(data, p, len)) {
+		data->has_error = true;
+		return false;
+	}
+
+	data->ofs += len;
+	return true;
+}
+
+/* read a uint8_t from a ASN1 buffer */
+bool asn1_read_uint8(struct asn1_data *data, uint8_t *v)
+{
+	return asn1_read(data, v, 1);
+}
+
+bool asn1_peek_uint8(struct asn1_data *data, uint8_t *v)
+{
+	return asn1_peek(data, v, 1);
+}
+
+bool asn1_peek_tag(struct asn1_data *data, uint8_t tag)
+{
+	uint8_t b;
+
+	if (asn1_tag_remaining(data) <= 0) {
+		return false;
+	}
+
+	if (!asn1_peek_uint8(data, &b))
+		return false;
+
+	return (b == tag);
+}
+
+/*
+ * just get the needed size the tag would consume
+ */
+static bool asn1_peek_tag_needed_size(struct asn1_data *data, uint8_t tag,
+				      size_t *size)
+{
+	off_t start_ofs = data->ofs;
+	uint8_t b;
+	size_t taglen = 0;
+
+	if (data->has_error) {
+		return false;
+	}
+
+	if (!asn1_read_uint8(data, &b)) {
+		data->ofs = start_ofs;
+		data->has_error = false;
+		return false;
+	}
+
+	if (b != tag) {
+		data->ofs = start_ofs;
+		data->has_error = false;
+		return false;
+	}
+
+	if (!asn1_read_uint8(data, &b)) {
+		data->ofs = start_ofs;
+		data->has_error = false;
+		return false;
+	}
+
+	if (b & 0x80) {
+		int n = b & 0x7f;
+		if (!asn1_read_uint8(data, &b)) {
+			data->ofs = start_ofs;
+			data->has_error = false;
+			return false;
+		}
+		if (n > 4) {
+			/*
+			 * We should not allow more than 4 bytes
+			 * for the encoding of the tag length.
+			 *
+			 * Otherwise we'd overflow the taglen
+			 * variable on 32 bit systems.
+			 */
+			data->ofs = start_ofs;
+			data->has_error = false;
+			return false;
+		}
+		taglen = b;
+		while (n > 1) {
+			size_t tmp_taglen;
+
+			if (!asn1_read_uint8(data, &b)) {
+				data->ofs = start_ofs;
+				data->has_error = false;
+				return false;
+			}
+
+			tmp_taglen = (taglen << 8) | b;
+
+			if ((tmp_taglen >> 8) != taglen) {
+				/* overflow */
+				data->ofs = start_ofs;
+				data->has_error = false;
+				return false;
+			}
+			taglen = tmp_taglen;
+
+			n--;
+		}
+	} else {
+		taglen = b;
+	}
+
+	*size = (data->ofs - start_ofs) + taglen;
+
+	data->ofs = start_ofs;
+	data->has_error = false;
+	return true;
+}
+
+/* start reading a nested asn1 structure */
+bool asn1_start_tag(struct asn1_data *data, uint8_t tag)
+{
+	uint8_t b;
+	struct nesting *nesting;
+
+	/*
+	 * Check the depth of the parse tree and prevent it from growing
+	 * too large.
+	 */
+	data->depth++;
+	if (data->depth > data->max_depth) {
+		data->has_error = true;
+		return false;
+	}
+
+	if (!asn1_read_uint8(data, &b))
+		return false;
+
+	if (b != tag) {
+		data->has_error = true;
+		return false;
+	}
+	nesting = talloc(data, struct nesting);
+	if (!nesting) {
+		data->has_error = true;
+		return false;
+	}
+
+	if (!asn1_read_uint8(data, &b)) {
+		return false;
+	}
+
+	if (b & 0x80) {
+		int n = b & 0x7f;
+		if (!asn1_read_uint8(data, &b))
+			return false;
+		nesting->taglen = b;
+		while (n > 1) {
+			size_t taglen;
+
+			if (!asn1_read_uint8(data, &b))
+				return false;
+
+			taglen = (nesting->taglen << 8) | b;
+
+			if ((taglen >> 8) != nesting->taglen) {
+				/* overflow */
+				data->has_error = true;
+				return false;
+			}
+			nesting->taglen = taglen;
+
+			n--;
+		}
+	} else {
+		nesting->taglen = b;
+	}
+	nesting->start = data->ofs;
+	nesting->next = data->nesting;
+	data->nesting = nesting;
+	if (asn1_tag_remaining(data) == -1) {
+		return false;
+	}
+	return !data->has_error;
+}
+
+/* stop reading a tag */
+bool asn1_end_tag(struct asn1_data *data)
+{
+	struct nesting *nesting;
+
+	if (data->depth == 0) {
+		smb_panic("Unbalanced ASN.1 Tag nesting");
+	}
+	data->depth--;
+	/* make sure we read it all */
+	if (asn1_tag_remaining(data) != 0) {
+		data->has_error = true;
+		return false;
+	}
+
+	nesting = data->nesting;
+
+	if (!nesting) {
+		data->has_error = true;
+		return false;
+	}
+
+	data->nesting = nesting->next;
+	talloc_free(nesting);
+	return true;
+}
+
+/* work out how many bytes are left in this nested tag */
+int asn1_tag_remaining(struct asn1_data *data)
+{
+	int remaining;
+	if (data->has_error) {
+		return -1;
+	}
+
+	if (!data->nesting) {
+		data->has_error = true;
+		return -1;
+	}
+	remaining = data->nesting->taglen - (data->ofs - data->nesting->start);
+	if (remaining > (data->length - data->ofs)) {
+		data->has_error = true;
+		return -1;
+	}
+	if (remaining < 0) {
+		data->has_error = true;
+		return -1;
+	}
+	return remaining;
+}
+
+/**
+ * Internal implementation for reading binary OIDs
+ * Reading is done as far in the buffer as valid OID
+ * till buffer ends or not valid sub-identifier is found.
+ */
+static bool _ber_read_OID_String_impl(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
+				      char **OID, size_t *bytes_eaten)
+{
+	int i;
+	uint8_t *b;
+	unsigned int v;
+	char *tmp_oid = NULL;
+
+	if (blob.length < 2) return false;
+
+	b = blob.data;
+
+	tmp_oid = talloc_asprintf(mem_ctx, "%u.%u", b[0]/40, b[0]%40);
+	if (!tmp_oid) goto nomem;
+
+	if (bytes_eaten != NULL) {
+		*bytes_eaten = 0;
+	}
+
+	for(i = 1, v = 0; i < blob.length; i++) {
+		v = (v<<7) | (b[i]&0x7f);
+		if ( ! (b[i] & 0x80)) {
+			tmp_oid = talloc_asprintf_append_buffer(tmp_oid, ".%u",  v);
+			v = 0;
+			if (bytes_eaten)
+				*bytes_eaten = i+1;
+		}
+		if (!tmp_oid) goto nomem;
+	}
+
+	*OID = tmp_oid;
+	return true;
+
+nomem:
+	return false;
+}
+
+/* read an object ID from a data blob */
+bool ber_read_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob, char **OID)
+{
+	size_t bytes_eaten;
+
+	if (!_ber_read_OID_String_impl(mem_ctx, blob, OID, &bytes_eaten))
+		return false;
+
+	return (bytes_eaten == blob.length);
+}
+
+/**
+ * Deserialize partial OID string.
+ * Partial OIDs are in the form:
+ *   1:2.5.6:0x81
+ *   1:2.5.6:0x8182
+ */
+bool ber_read_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
+				 char **partial_oid)
+{
+	size_t bytes_left;
+	size_t bytes_eaten;
+	char *identifier = NULL;
+	char *tmp_oid = NULL;
+
+	if (!_ber_read_OID_String_impl(mem_ctx, blob, &tmp_oid, &bytes_eaten))
+		return false;
+
+	if (bytes_eaten < blob.length) {
+		bytes_left = blob.length - bytes_eaten;
+		identifier = hex_encode_talloc(mem_ctx, &blob.data[bytes_eaten], bytes_left);
+		if (!identifier)	goto nomem;
+
+		*partial_oid = talloc_asprintf_append_buffer(tmp_oid, ":0x%s", identifier);
+		if (!*partial_oid)	goto nomem;
+		TALLOC_FREE(identifier);
+	} else {
+		*partial_oid = tmp_oid;
+	}
+
+	return true;
+
+nomem:
+	TALLOC_FREE(identifier);
+	TALLOC_FREE(tmp_oid);
+	return false;
+}
+
+/* read an object ID from a ASN1 buffer */
+bool asn1_read_OID(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **OID)
+{
+	DATA_BLOB blob;
+	int len;
+
+	if (!asn1_start_tag(data, ASN1_OID)) return false;
+
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+
+	blob = data_blob(NULL, len);
+	if (!blob.data) {
+		data->has_error = true;
+		return false;
+	}
+
+	if (!asn1_read(data, blob.data, len)) return false;
+	if (!asn1_end_tag(data)) {
+		data_blob_free(&blob);
+		return false;
+	}
+
+	if (!ber_read_OID_String(mem_ctx, blob, OID)) {
+		data->has_error = true;
+		data_blob_free(&blob);
+		return false;
+	}
+
+	data_blob_free(&blob);
+	return true;
+}
+
+/* check that the next object ID is correct */
+bool asn1_check_OID(struct asn1_data *data, const char *OID)
+{
+	char *id;
+
+	if (!asn1_read_OID(data, data, &id)) return false;
+
+	if (strcmp(id, OID) != 0) {
+		talloc_free(id);
+		data->has_error = true;
+		return false;
+	}
+	talloc_free(id);
+	return true;
+}
+
+/* read a LDAPString from a ASN1 buffer */
+bool asn1_read_LDAPString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
+{
+	int len;
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+	*s = talloc_array(mem_ctx, char, len+1);
+	if (! *s) {
+		data->has_error = true;
+		return false;
+	}
+	(*s)[len] = 0;
+	return asn1_read(data, *s, len);
+}
+
+
+/* read a GeneralString from a ASN1 buffer */
+bool asn1_read_GeneralString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
+{
+	if (!asn1_start_tag(data, ASN1_GENERAL_STRING)) return false;
+	if (!asn1_read_LDAPString(data, mem_ctx, s)) return false;
+	return asn1_end_tag(data);
+}
+
+
+/* read a octet string blob */
+bool asn1_read_OctetString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
+{
+	int len;
+	ZERO_STRUCTP(blob);
+	if (!asn1_start_tag(data, ASN1_OCTET_STRING)) return false;
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+	*blob = data_blob_talloc(mem_ctx, NULL, len+1);
+	if (!blob->data || blob->length < len) {
+		data->has_error = true;
+		return false;
+	}
+	if (!asn1_read(data, blob->data, len)) goto err;
+	if (!asn1_end_tag(data)) goto err;
+	blob->length--;
+	blob->data[len] = 0;
+	return true;
+
+  err:
+
+	data_blob_free(blob);
+	*blob = data_blob_null;
+	return false;
+}
+
+bool asn1_read_ContextSimple(struct asn1_data *data, TALLOC_CTX *mem_ctx, uint8_t num,
+			     DATA_BLOB *blob)
+{
+	int len;
+	ZERO_STRUCTP(blob);
+	if (!asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(num))) return false;
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+	*blob = data_blob_talloc(mem_ctx, NULL, len + 1);
+	if ((len != 0) && (!blob->data)) {
+		data->has_error = true;
+		return false;
+	}
+	if (!asn1_read(data, blob->data, len)) return false;
+	blob->length--;
+	blob->data[len] = 0;
+	return asn1_end_tag(data);
+}
+
+/* read an integer without tag*/
+bool asn1_read_implicit_Integer(struct asn1_data *data, int *i)
+{
+	uint8_t b;
+	uint32_t x = 0;
+	bool first_byte = true;
+
+	*i = 0;
+
+	while (!data->has_error && asn1_tag_remaining(data)>0) {
+		if (!asn1_read_uint8(data, &b)) return false;
+		if (first_byte) {
+			if (b & 0x80) {
+				/* Number is negative. */
+				x = (uint32_t)-1;
+			}
+			first_byte = false;
+		}
+		x = (x << 8) + b;
+	}
+	*i = (int)x;
+
+	return !data->has_error;
+}
+
+/* read an integer */
+bool asn1_read_Integer(struct asn1_data *data, int *i)
+{
+	*i = 0;
+
+	if (!asn1_start_tag(data, ASN1_INTEGER)) return false;
+	if (!asn1_read_implicit_Integer(data, i)) return false;
+	return asn1_end_tag(data);
+}
+
+/* read a BIT STRING */
+bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding)
+{
+	int len;
+	ZERO_STRUCTP(blob);
+	if (!asn1_start_tag(data, ASN1_BIT_STRING)) return false;
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+	if (!asn1_read_uint8(data, padding)) return false;
+
+	*blob = data_blob_talloc(mem_ctx, NULL, len+1);
+	if (!blob->data || blob->length < len) {
+		data->has_error = true;
+		return false;
+	}
+	if (asn1_read(data, blob->data, len - 1)) {
+		blob->length--;
+		blob->data[len] = 0;
+		asn1_end_tag(data);
+	}
+
+	if (data->has_error) {
+		data_blob_free(blob);
+		*blob = data_blob_null;
+		*padding = 0;
+		return false;
+	}
+	return true;
+}
+
+/* read a non-negative enumerated value */
+bool asn1_read_enumerated(struct asn1_data *data, int *v)
+{
+	unsigned int val_will_wrap = (0xFFU << ((sizeof(int)*8)-8));
+	*v = 0;
+
+	if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
+	while (!data->has_error && asn1_tag_remaining(data)>0) {
+		uint8_t b;
+		if (!asn1_read_uint8(data, &b)) {
+			return false;
+		}
+		if (*v & val_will_wrap) {
+			/*
+			 * There is something already in
+			 * the top byte of the int. If we
+			 * shift left by 8 it's going to
+			 * wrap. Prevent this.
+			 */
+			data->has_error = true;
+			return false;
+		}
+		/*
+		 * To please/fool the Undefined Behaviour Sanitizer we cast to
+		 * unsigned for the left shift.
+		 */
+		*v = ((unsigned int)*v << 8) + b;
+		if (*v < 0) {
+			/* ASN1_ENUMERATED can't be -ve. */
+			data->has_error = true;
+			return false;
+		}
+	}
+	return asn1_end_tag(data);
+}
+
+/* write an enumerated value to the stream */
+bool asn1_write_enumerated(struct asn1_data *data, uint8_t v)
+{
+	if (!asn1_push_tag(data, ASN1_ENUMERATED)) return false;
+	if (!asn1_write_uint8(data, v)) return false;
+	return asn1_pop_tag(data);
+}
+
+/*
+  Get us the data just written without copying
+*/
+bool asn1_blob(const struct asn1_data *asn1, DATA_BLOB *blob)
+{
+	if (asn1->has_error) {
+		return false;
+	}
+	if (asn1->nesting != NULL) {
+		return false;
+	}
+	blob->data = asn1->data;
+	blob->length = asn1->length;
+	return true;
+}
+
+bool asn1_extract_blob(struct asn1_data *asn1, TALLOC_CTX *mem_ctx,
+		       DATA_BLOB *pblob)
+{
+	DATA_BLOB blob;
+
+	if (!asn1_blob(asn1, &blob)) {
+		return false;
+	}
+
+	*pblob = (DATA_BLOB) { .length = blob.length };
+	pblob->data = talloc_move(mem_ctx, &blob.data);
+
+	/*
+	 * Stop access from here on
+	 */
+	asn1->has_error = true;
+
+	return true;
+}
+
+/*
+  Fill in an asn1 struct without making a copy
+*/
+void asn1_load_nocopy(struct asn1_data *data, uint8_t *buf, size_t len)
+{
+	/*
+	 * Save max_depth
+	 */
+	unsigned max_depth = data->max_depth;
+	ZERO_STRUCTP(data);
+	data->data = buf;
+	data->length = len;
+	data->max_depth = max_depth;
+}
+
+int asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
+{
+	struct asn1_data asn1;
+	size_t size;
+	bool ok;
+
+	ZERO_STRUCT(asn1);
+	asn1.data = blob.data;
+	asn1.length = blob.length;
+
+	ok = asn1_peek_tag_needed_size(&asn1, tag, &size);
+	if (!ok) {
+		return EMSGSIZE;
+	}
+
+	if (size > blob.length) {
+		*packet_size = size;
+		return EAGAIN;
+	}
+
+	*packet_size = size;
+	return 0;
+}
+
+/*
+ * Get the length of the ASN.1 data
+ */
+size_t asn1_get_length(const struct asn1_data *asn1) {
+	return asn1->length;
+}