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-rw-r--r--lib/util/asn1.c1176
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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 00:42:25 +0000