diff options
Diffstat (limited to 'src/libcharon/encoding/payloads/cert_payload.c')
-rw-r--r-- | src/libcharon/encoding/payloads/cert_payload.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/src/libcharon/encoding/payloads/cert_payload.c b/src/libcharon/encoding/payloads/cert_payload.c new file mode 100644 index 000000000..6dd3141f0 --- /dev/null +++ b/src/libcharon/encoding/payloads/cert_payload.c @@ -0,0 +1,340 @@ +/* + * 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 <http://www.fsf.org/copyleft/gpl.txt>. + * + * 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. + */ + +#include <stddef.h> +#include <ctype.h> + +#include <daemon.h> + +#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, 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(); + + this->encoding = ENC_X509_HASH_AND_URL; + this->data = chunk_cat("cc", hash, chunk_create(url, strlen(url))); + this->payload_length = CERT_PAYLOAD_HEADER_LENGTH + this->data.len; + return &this->public; +} + |