diff options
Diffstat (limited to 'lib/libgssapi/gss_decapsulate_token.c')
-rw-r--r-- | lib/libgssapi/gss_decapsulate_token.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/lib/libgssapi/gss_decapsulate_token.c b/lib/libgssapi/gss_decapsulate_token.c new file mode 100644 index 0000000..65ff46a --- /dev/null +++ b/lib/libgssapi/gss_decapsulate_token.c @@ -0,0 +1,107 @@ +/*- + * Copyright (c) 2008 Doug Rabson + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <gssapi/gssapi.h> +#include <stdlib.h> +#include <string.h> + +#include "utils.h" + +OM_uint32 +gss_decapsulate_token(const gss_buffer_t input_token, gss_OID oid, + gss_buffer_t output_token) +{ + unsigned char *p = input_token->value; + size_t len = input_token->length; + size_t a, b; + gss_OID_desc mech_oid; + + _gss_buffer_zero(output_token); + + /* + * Token must start with [APPLICATION 0] SEQUENCE. + */ + if (len == 0 || *p != 0x60) + return (GSS_S_DEFECTIVE_TOKEN); + p++; + len--; + + /* + * Decode the length and make sure it agrees with the + * token length. + */ + if (len == 0) + return (GSS_S_DEFECTIVE_TOKEN); + if ((*p & 0x80) == 0) { + a = *p; + p++; + len--; + } else { + b = *p & 0x7f; + p++; + len--; + if (len < b) + return (GSS_S_DEFECTIVE_TOKEN); + a = 0; + while (b) { + a = (a << 8) | *p; + p++; + len--; + b--; + } + } + if (a != len) + return (GSS_S_DEFECTIVE_TOKEN); + + /* + * Decode the OID for the mechanism. Simplify life by + * assuming that the OID length is less than 128 bytes. + */ + if (len < 2 || *p != 0x06) + return (GSS_S_DEFECTIVE_TOKEN); + if ((p[1] & 0x80) || p[1] > (len - 2)) + return (GSS_S_DEFECTIVE_TOKEN); + mech_oid.length = p[1]; + p += 2; + len -= 2; + mech_oid.elements = p; + + if (!gss_oid_equal(&mech_oid, oid)) + return (GSS_S_FAILURE); + + p += mech_oid.length; + len -= mech_oid.length; + + output_token->length = len; + output_token->value = malloc(len); + if (!output_token->value) + return (GSS_S_DEFECTIVE_TOKEN); + memcpy(output_token->value, p, len); + + return (GSS_S_COMPLETE); +} |