/* * Copyright (C) 2008 Tobias Brunner * Copyright (C) 2005-2007 Martin Willi * Copyright (C) 2005 Jan Hutter * Hochschule fuer Technik Rapperswil * * 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 2 of the License, or (at your * option) any later version. See . * * 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. * * $Id: cert_payload.c 3852 2008-04-18 21:27:08Z andreas $ */ #include #include #include #include "cert_payload.h" ENUM(cert_encoding_names, ENC_PKCS7_WRAPPED_X509, ENC_OCSP_CONTENT, "ENC_PKCS7_WRAPPED_X509", "ENC_PGP", "ENC_DNS_SIGNED_KEY", "ENC_X509_SIGNATURE", "ENC_X509_KEY_EXCHANGE", "ENC_KERBEROS_TOKENS", "ENC_CRL", "ENC_ARL", "ENC_SPKI", "ENC_X509_ATTRIBUTE", "ENC_RAW_RSA_KEY", "ENC_X509_HASH_AND_URL", "ENC_X509_HASH_AND_URL_BUNDLE", "ENC_OCSP_CONTENT", ); typedef struct private_cert_payload_t private_cert_payload_t; /** * Private data of an cert_payload_t object. * */ struct private_cert_payload_t { /** * Public cert_payload_t interface. */ cert_payload_t public; /** * Next payload type. */ u_int8_t next_payload; /** * Critical flag. */ bool critical; /** * Length of this payload. */ u_int16_t payload_length; /** * Encoding of the CERT Data. */ u_int8_t encoding; /** * The contained cert data value. */ chunk_t data; /** * TRUE if the "Hash and URL" data is invalid */ bool invalid_hash_and_url; }; /** * Encoding rules to parse or generate a CERT payload * * The defined offsets are the positions in a object of type * private_cert_payload_t. * */ encoding_rule_t cert_payload_encodings[] = { /* 1 Byte next payload type, stored in the field next_payload */ { U_INT_8, offsetof(private_cert_payload_t, next_payload) }, /* the critical bit */ { FLAG, offsetof(private_cert_payload_t, critical) }, /* 7 Bit reserved bits, nowhere stored */ { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, { RESERVED_BIT, 0 }, /* Length of the whole payload*/ { PAYLOAD_LENGTH, offsetof(private_cert_payload_t, payload_length)}, /* 1 Byte CERT type*/ { U_INT_8, offsetof(private_cert_payload_t, encoding) }, /* some cert data bytes, length is defined in PAYLOAD_LENGTH */ { CERT_DATA, offsetof(private_cert_payload_t, data) } }; /* 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! Next Payload !C! RESERVED ! Payload Length ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! Cert Encoding ! ! +-+-+-+-+-+-+-+-+ ! ~ Certificate Data ~ ! ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ /** * Implementation of payload_t.verify. */ static status_t verify(private_cert_payload_t *this) { if (this->encoding == ENC_X509_HASH_AND_URL || this->encoding == ENC_X509_HASH_AND_URL_BUNDLE) { /* coarse verification of "Hash and URL" encoded certificates */ if (this->data.len <= 20) { DBG1(DBG_ENC, "invalid payload length for hash-and-url (%d), ignore", this->data.len); this->invalid_hash_and_url = TRUE; return SUCCESS; } int i = 20; /* skipping the hash */ for (; i < this->data.len; ++i) { if (this->data.ptr[i] == '\0') { /* null terminated, fine */ return SUCCESS; } else if (!isprint(this->data.ptr[i])) { DBG1(DBG_ENC, "non printable characters in url of hash-and-url" " encoded certificate payload, ignore"); this->invalid_hash_and_url = TRUE; return SUCCESS; } } /* URL is not null terminated, correct that */ chunk_t data = chunk_alloc(this->data.len + 1); memcpy(data.ptr, this->data.ptr, this->data.len); data.ptr[this->data.len] = '\0'; chunk_free(&this->data); this->data = data; } return SUCCESS; } /** * Implementation of cert_payload_t.get_encoding_rules. */ static void get_encoding_rules(private_cert_payload_t *this, encoding_rule_t **rules, size_t *rule_count) { *rules = cert_payload_encodings; *rule_count = sizeof(cert_payload_encodings) / sizeof(encoding_rule_t); } /** * Implementation of payload_t.get_type. */ static payload_type_t get_payload_type(private_cert_payload_t *this) { return CERTIFICATE; } /** * Implementation of payload_t.get_next_type. */ static payload_type_t get_next_type(private_cert_payload_t *this) { return this->next_payload; } /** * Implementation of payload_t.set_next_type. */ static void set_next_type(private_cert_payload_t *this,payload_type_t type) { this->next_payload = type; } /** * Implementation of payload_t.get_length. */ static size_t get_length(private_cert_payload_t *this) { return this->payload_length; } /** * Implementation of cert_payload_t.get_cert_encoding. */ static cert_encoding_t get_cert_encoding(private_cert_payload_t *this) { return this->encoding; } /** * Implementation of cert_payload_t.get_cert. */ static certificate_t *get_cert(private_cert_payload_t *this) { if (this->encoding != ENC_X509_SIGNATURE) { return NULL; } return lib->creds->create(lib->creds, CRED_CERTIFICATE, CERT_X509, BUILD_BLOB_ASN1_DER, chunk_clone(this->data), BUILD_END); } /** * Implementation of cert_payload_t.get_hash. */ static chunk_t get_hash(private_cert_payload_t *this) { chunk_t hash = chunk_empty; if ((this->encoding != ENC_X509_HASH_AND_URL && this->encoding != ENC_X509_HASH_AND_URL_BUNDLE) || this->invalid_hash_and_url) { return hash; } hash.ptr = this->data.ptr; hash.len = 20; return hash; } /** * Implementation of cert_payload_t.get_url. */ static char *get_url(private_cert_payload_t *this) { if ((this->encoding != ENC_X509_HASH_AND_URL && this->encoding != ENC_X509_HASH_AND_URL_BUNDLE) || this->invalid_hash_and_url) { return NULL; } return (char*)this->data.ptr + 20; } /** * Implementation of payload_t.destroy and cert_payload_t.destroy. */ static void destroy(private_cert_payload_t *this) { chunk_free(&this->data); free(this); } /* * Described in header */ cert_payload_t *cert_payload_create() { private_cert_payload_t *this = malloc_thing(private_cert_payload_t); this->public.payload_interface.verify = (status_t (*) (payload_t*))verify; this->public.payload_interface.get_encoding_rules = (void (*) (payload_t*,encoding_rule_t**, size_t*))get_encoding_rules; this->public.payload_interface.get_length = (size_t (*) (payload_t*))get_length; this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t*))get_next_type; this->public.payload_interface.set_next_type = (void (*) (payload_t*,payload_type_t))set_next_type; this->public.payload_interface.get_type = (payload_type_t (*) (payload_t*))get_payload_type; this->public.payload_interface.destroy = (void (*) (payload_t*))destroy; this->public.destroy = (void (*) (cert_payload_t*))destroy; this->public.get_cert = (certificate_t* (*) (cert_payload_t*))get_cert; this->public.get_cert_encoding = (cert_encoding_t (*) (cert_payload_t*))get_cert_encoding; this->public.get_hash = (chunk_t (*) (cert_payload_t*))get_hash; this->public.get_url = (char* (*) (cert_payload_t*))get_url; this->critical = FALSE; this->next_payload = NO_PAYLOAD; this->payload_length = CERT_PAYLOAD_HEADER_LENGTH; this->data = chunk_empty; this->encoding = 0; this->invalid_hash_and_url = FALSE; return &this->public; } /* * Described in header */ cert_payload_t *cert_payload_create_from_cert(certificate_t *cert) { private_cert_payload_t *this = (private_cert_payload_t*)cert_payload_create(); switch (cert->get_type(cert)) { case CERT_X509: this->encoding = ENC_X509_SIGNATURE; break; default: DBG1(DBG_ENC, "embedding %N certificate in payload failed", certificate_type_names, cert->get_type(cert)); free(this); return NULL; } this->data = cert->get_encoding(cert); this->payload_length = CERT_PAYLOAD_HEADER_LENGTH + this->data.len; return &this->public; } /* * Described in header */ cert_payload_t *cert_payload_create_from_hash_and_url(chunk_t hash, char *url) { private_cert_payload_t *this = (private_cert_payload_t*)cert_payload_create(); chunk_t url_chunk; this->encoding = ENC_X509_HASH_AND_URL; url_chunk.ptr = url; url_chunk.len = strlen(url) + 1; this->data = chunk_cat("cc", hash, url_chunk); this->payload_length = CERT_PAYLOAD_HEADER_LENGTH + this->data.len; return &this->public; }