// SPDX-License-Identifier: GPL-2.0-or-later /* * CIPSO - Commercial IP Security Option * * This is an implementation of the CIPSO 2.2 protocol as specified in * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in * FIPS-188. While CIPSO never became a full IETF RFC standard many vendors * have chosen to adopt the protocol and over the years it has become a * de-facto standard for labeled networking. * * The CIPSO draft specification can be found in the kernel's Documentation * directory as well as the following URL: * https://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt * The FIPS-188 specification can be found at the following URL: * https://www.itl.nist.gov/fipspubs/fip188.htm * * Author: Paul Moore <[email protected]> */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 */ #include <linux/init.h> #include <linux/types.h> #include <linux/rcupdate.h> #include <linux/list.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/jhash.h> #include <linux/audit.h> #include <linux/slab.h> #include <net/ip.h> #include <net/icmp.h> #include <net/tcp.h> #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <linux/atomic.h> #include <linux/bug.h> #include <asm/unaligned.h> /* List of available DOI definitions */ /* XXX - This currently assumes a minimal number of different DOIs in use, * if in practice there are a lot of different DOIs this list should * probably be turned into a hash table or something similar so we * can do quick lookups. */ static DEFINE_SPINLOCK(cipso_v4_doi_list_lock); static LIST_HEAD(cipso_v4_doi_list); /* Label mapping cache */ int cipso_v4_cache_enabled = …; int cipso_v4_cache_bucketsize = …; #define CIPSO_V4_CACHE_BUCKETBITS … #define CIPSO_V4_CACHE_BUCKETS … #define CIPSO_V4_CACHE_REORDERLIMIT … struct cipso_v4_map_cache_bkt { … }; struct cipso_v4_map_cache_entry { … }; static struct cipso_v4_map_cache_bkt *cipso_v4_cache; /* Restricted bitmap (tag #1) flags */ int cipso_v4_rbm_optfmt; int cipso_v4_rbm_strictvalid = …; /* * Protocol Constants */ /* Maximum size of the CIPSO IP option, derived from the fact that the maximum * IPv4 header size is 60 bytes and the base IPv4 header is 20 bytes long. */ #define CIPSO_V4_OPT_LEN_MAX … /* Length of the base CIPSO option, this includes the option type (1 byte), the * option length (1 byte), and the DOI (4 bytes). */ #define CIPSO_V4_HDR_LEN … /* Base length of the restrictive category bitmap tag (tag #1). */ #define CIPSO_V4_TAG_RBM_BLEN … /* Base length of the enumerated category tag (tag #2). */ #define CIPSO_V4_TAG_ENUM_BLEN … /* Base length of the ranged categories bitmap tag (tag #5). */ #define CIPSO_V4_TAG_RNG_BLEN … /* The maximum number of category ranges permitted in the ranged category tag * (tag #5). You may note that the IETF draft states that the maximum number * of category ranges is 7, but if the low end of the last category range is * zero then it is possible to fit 8 category ranges because the zero should * be omitted. */ #define CIPSO_V4_TAG_RNG_CAT_MAX … /* Base length of the local tag (non-standard tag). * Tag definition (may change between kernel versions) * * 0 8 16 24 32 * +----------+----------+----------+----------+ * | 10000000 | 00000110 | 32-bit secid value | * +----------+----------+----------+----------+ * | in (host byte order)| * +----------+----------+ * */ #define CIPSO_V4_TAG_LOC_BLEN … /* * Helper Functions */ /** * cipso_v4_cache_entry_free - Frees a cache entry * @entry: the entry to free * * Description: * This function frees the memory associated with a cache entry including the * LSM cache data if there are no longer any users, i.e. reference count == 0. * */ static void cipso_v4_cache_entry_free(struct cipso_v4_map_cache_entry *entry) { … } /** * cipso_v4_map_cache_hash - Hashing function for the CIPSO cache * @key: the hash key * @key_len: the length of the key in bytes * * Description: * The CIPSO tag hashing function. Returns a 32-bit hash value. * */ static u32 cipso_v4_map_cache_hash(const unsigned char *key, u32 key_len) { … } /* * Label Mapping Cache Functions */ /** * cipso_v4_cache_init - Initialize the CIPSO cache * * Description: * Initializes the CIPSO label mapping cache, this function should be called * before any of the other functions defined in this file. Returns zero on * success, negative values on error. * */ static int __init cipso_v4_cache_init(void) { … } /** * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache * * Description: * Invalidates and frees any entries in the CIPSO cache. * */ void cipso_v4_cache_invalidate(void) { … } /** * cipso_v4_cache_check - Check the CIPSO cache for a label mapping * @key: the buffer to check * @key_len: buffer length in bytes * @secattr: the security attribute struct to use * * Description: * This function checks the cache to see if a label mapping already exists for * the given key. If there is a match then the cache is adjusted and the * @secattr struct is populated with the correct LSM security attributes. The * cache is adjusted in the following manner if the entry is not already the * first in the cache bucket: * * 1. The cache entry's activity counter is incremented * 2. The previous (higher ranking) entry's activity counter is decremented * 3. If the difference between the two activity counters is geater than * CIPSO_V4_CACHE_REORDERLIMIT the two entries are swapped * * Returns zero on success, -ENOENT for a cache miss, and other negative values * on error. * */ static int cipso_v4_cache_check(const unsigned char *key, u32 key_len, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_cache_add - Add an entry to the CIPSO cache * @cipso_ptr: pointer to CIPSO IP option * @secattr: the packet's security attributes * * Description: * Add a new entry into the CIPSO label mapping cache. Add the new entry to * head of the cache bucket's list, if the cache bucket is out of room remove * the last entry in the list first. It is important to note that there is * currently no checking for duplicate keys. Returns zero on success, * negative values on failure. * */ int cipso_v4_cache_add(const unsigned char *cipso_ptr, const struct netlbl_lsm_secattr *secattr) { … } /* * DOI List Functions */ /** * cipso_v4_doi_search - Searches for a DOI definition * @doi: the DOI to search for * * Description: * Search the DOI definition list for a DOI definition with a DOI value that * matches @doi. The caller is responsible for calling rcu_read_[un]lock(). * Returns a pointer to the DOI definition on success and NULL on failure. */ static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi) { … } /** * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine * @doi_def: the DOI structure * @audit_info: NetLabel audit information * * Description: * The caller defines a new DOI for use by the CIPSO engine and calls this * function to add it to the list of acceptable domains. The caller must * ensure that the mapping table specified in @doi_def->map meets all of the * requirements of the mapping type (see cipso_ipv4.h for details). Returns * zero on success and non-zero on failure. * */ int cipso_v4_doi_add(struct cipso_v4_doi *doi_def, struct netlbl_audit *audit_info) { … } /** * cipso_v4_doi_free - Frees a DOI definition * @doi_def: the DOI definition * * Description: * This function frees all of the memory associated with a DOI definition. * */ void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) { … } /** * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer * @entry: the entry's RCU field * * Description: * This function is designed to be used as a callback to the call_rcu() * function so that the memory allocated to the DOI definition can be released * safely. * */ static void cipso_v4_doi_free_rcu(struct rcu_head *entry) { … } /** * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine * @doi: the DOI value * @audit_info: NetLabel audit information * * Description: * Removes a DOI definition from the CIPSO engine. The NetLabel routines will * be called to release their own LSM domain mappings as well as our own * domain list. Returns zero on success and negative values on failure. * */ int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) { … } /** * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition * @doi: the DOI value * * Description: * Searches for a valid DOI definition and if one is found it is returned to * the caller. Otherwise NULL is returned. The caller must ensure that * rcu_read_lock() is held while accessing the returned definition and the DOI * definition reference count is decremented when the caller is done. * */ struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) { … } /** * cipso_v4_doi_putdef - Releases a reference for the given DOI definition * @doi_def: the DOI definition * * Description: * Releases a DOI definition reference obtained from cipso_v4_doi_getdef(). * */ void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) { … } /** * cipso_v4_doi_walk - Iterate through the DOI definitions * @skip_cnt: skip past this number of DOI definitions, updated * @callback: callback for each DOI definition * @cb_arg: argument for the callback function * * Description: * Iterate over the DOI definition list, skipping the first @skip_cnt entries. * For each entry call @callback, if @callback returns a negative value stop * 'walking' through the list and return. Updates the value in @skip_cnt upon * return. Returns zero on success, negative values on failure. * */ int cipso_v4_doi_walk(u32 *skip_cnt, int (*callback) (struct cipso_v4_doi *doi_def, void *arg), void *cb_arg) { … } /* * Label Mapping Functions */ /** * cipso_v4_map_lvl_valid - Checks to see if the given level is understood * @doi_def: the DOI definition * @level: the level to check * * Description: * Checks the given level against the given DOI definition and returns a * negative value if the level does not have a valid mapping and a zero value * if the level is defined by the DOI. * */ static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) { … } /** * cipso_v4_map_lvl_hton - Perform a level mapping from the host to the network * @doi_def: the DOI definition * @host_lvl: the host MLS level * @net_lvl: the network/CIPSO MLS level * * Description: * Perform a label mapping to translate a local MLS level to the correct * CIPSO level using the given DOI definition. Returns zero on success, * negative values otherwise. * */ static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def, u32 host_lvl, u32 *net_lvl) { … } /** * cipso_v4_map_lvl_ntoh - Perform a level mapping from the network to the host * @doi_def: the DOI definition * @net_lvl: the network/CIPSO MLS level * @host_lvl: the host MLS level * * Description: * Perform a label mapping to translate a CIPSO level to the correct local MLS * level using the given DOI definition. Returns zero on success, negative * values otherwise. * */ static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def, u32 net_lvl, u32 *host_lvl) { … } /** * cipso_v4_map_cat_rbm_valid - Checks to see if the category bitmap is valid * @doi_def: the DOI definition * @bitmap: category bitmap * @bitmap_len: bitmap length in bytes * * Description: * Checks the given category bitmap against the given DOI definition and * returns a negative value if any of the categories in the bitmap do not have * a valid mapping and a zero value if all of the categories are valid. * */ static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def, const unsigned char *bitmap, u32 bitmap_len) { … } /** * cipso_v4_map_cat_rbm_hton - Perform a category mapping from host to network * @doi_def: the DOI definition * @secattr: the security attributes * @net_cat: the zero'd out category bitmap in network/CIPSO format * @net_cat_len: the length of the CIPSO bitmap in bytes * * Description: * Perform a label mapping to translate a local MLS category bitmap to the * correct CIPSO bitmap using the given DOI definition. Returns the minimum * size in bytes of the network bitmap on success, negative values otherwise. * */ static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *net_cat, u32 net_cat_len) { … } /** * cipso_v4_map_cat_rbm_ntoh - Perform a category mapping from network to host * @doi_def: the DOI definition * @net_cat: the category bitmap in network/CIPSO format * @net_cat_len: the length of the CIPSO bitmap in bytes * @secattr: the security attributes * * Description: * Perform a label mapping to translate a CIPSO bitmap to the correct local * MLS category bitmap using the given DOI definition. Returns zero on * success, negative values on failure. * */ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, const unsigned char *net_cat, u32 net_cat_len, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid * @doi_def: the DOI definition * @enumcat: category list * @enumcat_len: length of the category list in bytes * * Description: * Checks the given categories against the given DOI definition and returns a * negative value if any of the categories do not have a valid mapping and a * zero value if all of the categories are valid. * */ static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def, const unsigned char *enumcat, u32 enumcat_len) { … } /** * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network * @doi_def: the DOI definition * @secattr: the security attributes * @net_cat: the zero'd out category list in network/CIPSO format * @net_cat_len: the length of the CIPSO category list in bytes * * Description: * Perform a label mapping to translate a local MLS category bitmap to the * correct CIPSO category list using the given DOI definition. Returns the * size in bytes of the network category bitmap on success, negative values * otherwise. * */ static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *net_cat, u32 net_cat_len) { … } /** * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host * @doi_def: the DOI definition * @net_cat: the category list in network/CIPSO format * @net_cat_len: the length of the CIPSO bitmap in bytes * @secattr: the security attributes * * Description: * Perform a label mapping to translate a CIPSO category list to the correct * local MLS category bitmap using the given DOI definition. Returns zero on * success, negative values on failure. * */ static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def, const unsigned char *net_cat, u32 net_cat_len, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_map_cat_rng_valid - Checks to see if the categories are valid * @doi_def: the DOI definition * @rngcat: category list * @rngcat_len: length of the category list in bytes * * Description: * Checks the given categories against the given DOI definition and returns a * negative value if any of the categories do not have a valid mapping and a * zero value if all of the categories are valid. * */ static int cipso_v4_map_cat_rng_valid(const struct cipso_v4_doi *doi_def, const unsigned char *rngcat, u32 rngcat_len) { … } /** * cipso_v4_map_cat_rng_hton - Perform a category mapping from host to network * @doi_def: the DOI definition * @secattr: the security attributes * @net_cat: the zero'd out category list in network/CIPSO format * @net_cat_len: the length of the CIPSO category list in bytes * * Description: * Perform a label mapping to translate a local MLS category bitmap to the * correct CIPSO category list using the given DOI definition. Returns the * size in bytes of the network category bitmap on success, negative values * otherwise. * */ static int cipso_v4_map_cat_rng_hton(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *net_cat, u32 net_cat_len) { … } /** * cipso_v4_map_cat_rng_ntoh - Perform a category mapping from network to host * @doi_def: the DOI definition * @net_cat: the category list in network/CIPSO format * @net_cat_len: the length of the CIPSO bitmap in bytes * @secattr: the security attributes * * Description: * Perform a label mapping to translate a CIPSO category list to the correct * local MLS category bitmap using the given DOI definition. Returns zero on * success, negative values on failure. * */ static int cipso_v4_map_cat_rng_ntoh(const struct cipso_v4_doi *doi_def, const unsigned char *net_cat, u32 net_cat_len, struct netlbl_lsm_secattr *secattr) { … } /* * Protocol Handling Functions */ /** * cipso_v4_gentag_hdr - Generate a CIPSO option header * @doi_def: the DOI definition * @len: the total tag length in bytes, not including this header * @buf: the CIPSO option buffer * * Description: * Write a CIPSO header into the beginning of @buffer. * */ static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, unsigned char *buf, u32 len) { … } /** * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) * @doi_def: the DOI definition * @secattr: the security attributes * @buffer: the option buffer * @buffer_len: length of buffer in bytes * * Description: * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The * actual buffer length may be larger than the indicated size due to * translation between host and network category bitmaps. Returns the size of * the tag on success, negative values on failure. * */ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *buffer, u32 buffer_len) { … } /** * cipso_v4_parsetag_rbm - Parse a CIPSO restricted bitmap tag * @doi_def: the DOI definition * @tag: the CIPSO tag * @secattr: the security attributes * * Description: * Parse a CIPSO restricted bitmap tag (tag type #1) and return the security * attributes in @secattr. Return zero on success, negatives values on * failure. * */ static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, const unsigned char *tag, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2) * @doi_def: the DOI definition * @secattr: the security attributes * @buffer: the option buffer * @buffer_len: length of buffer in bytes * * Description: * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the * size of the tag on success, negative values on failure. * */ static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *buffer, u32 buffer_len) { … } /** * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag * @doi_def: the DOI definition * @tag: the CIPSO tag * @secattr: the security attributes * * Description: * Parse a CIPSO enumerated tag (tag type #2) and return the security * attributes in @secattr. Return zero on success, negatives values on * failure. * */ static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def, const unsigned char *tag, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_gentag_rng - Generate a CIPSO ranged tag (type #5) * @doi_def: the DOI definition * @secattr: the security attributes * @buffer: the option buffer * @buffer_len: length of buffer in bytes * * Description: * Generate a CIPSO option using the ranged tag, tag type #5. Returns the * size of the tag on success, negative values on failure. * */ static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *buffer, u32 buffer_len) { … } /** * cipso_v4_parsetag_rng - Parse a CIPSO ranged tag * @doi_def: the DOI definition * @tag: the CIPSO tag * @secattr: the security attributes * * Description: * Parse a CIPSO ranged tag (tag type #5) and return the security attributes * in @secattr. Return zero on success, negatives values on failure. * */ static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, const unsigned char *tag, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard) * @doi_def: the DOI definition * @secattr: the security attributes * @buffer: the option buffer * @buffer_len: length of buffer in bytes * * Description: * Generate a CIPSO option using the local tag. Returns the size of the tag * on success, negative values on failure. * */ static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, unsigned char *buffer, u32 buffer_len) { … } /** * cipso_v4_parsetag_loc - Parse a CIPSO local tag * @doi_def: the DOI definition * @tag: the CIPSO tag * @secattr: the security attributes * * Description: * Parse a CIPSO local tag and return the security attributes in @secattr. * Return zero on success, negatives values on failure. * */ static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def, const unsigned char *tag, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_optptr - Find the CIPSO option in the packet * @skb: the packet * * Description: * Parse the packet's IP header looking for a CIPSO option. Returns a pointer * to the start of the CIPSO option on success, NULL if one is not found. * */ unsigned char *cipso_v4_optptr(const struct sk_buff *skb) { … } /** * cipso_v4_validate - Validate a CIPSO option * @skb: the packet * @option: the start of the option, on error it is set to point to the error * * Description: * This routine is called to validate a CIPSO option, it checks all of the * fields to ensure that they are at least valid, see the draft snippet below * for details. If the option is valid then a zero value is returned and * the value of @option is unchanged. If the option is invalid then a * non-zero value is returned and @option is adjusted to point to the * offending portion of the option. From the IETF draft ... * * "If any field within the CIPSO options, such as the DOI identifier, is not * recognized the IP datagram is discarded and an ICMP 'parameter problem' * (type 12) is generated and returned. The ICMP code field is set to 'bad * parameter' (code 0) and the pointer is set to the start of the CIPSO field * that is unrecognized." * */ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) { … } /** * cipso_v4_error - Send the correct response for a bad packet * @skb: the packet * @error: the error code * @gateway: CIPSO gateway flag * * Description: * Based on the error code given in @error, send an ICMP error message back to * the originating host. From the IETF draft ... * * "If the contents of the CIPSO [option] are valid but the security label is * outside of the configured host or port label range, the datagram is * discarded and an ICMP 'destination unreachable' (type 3) is generated and * returned. The code field of the ICMP is set to 'communication with * destination network administratively prohibited' (code 9) or to * 'communication with destination host administratively prohibited' * (code 10). The value of the code is dependent on whether the originator * of the ICMP message is acting as a CIPSO host or a CIPSO gateway. The * recipient of the ICMP message MUST be able to handle either value. The * same procedure is performed if a CIPSO [option] can not be added to an * IP packet because it is too large to fit in the IP options area." * * "If the error is triggered by receipt of an ICMP message, the message is * discarded and no response is permitted (consistent with general ICMP * processing rules)." * */ void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) { … } /** * cipso_v4_genopt - Generate a CIPSO option * @buf: the option buffer * @buf_len: the size of opt_buf * @doi_def: the CIPSO DOI to use * @secattr: the security attributes * * Description: * Generate a CIPSO option using the DOI definition and security attributes * passed to the function. Returns the length of the option on success and * negative values on failure. * */ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { … } static int cipso_v4_get_actual_opt_len(const unsigned char *data, int len) { … } /** * cipso_v4_sock_setattr - Add a CIPSO option to a socket * @sk: the socket * @doi_def: the CIPSO DOI to use * @secattr: the specific security attributes of the socket * @sk_locked: true if caller holds the socket lock * * Description: * Set the CIPSO option on the given socket using the DOI definition and * security attributes passed to the function. This function requires * exclusive access to @sk, which means it either needs to be in the * process of being created or locked. Returns zero on success and negative * values on failure. * */ int cipso_v4_sock_setattr(struct sock *sk, const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, bool sk_locked) { … } /** * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket * @req: the connection request socket * @doi_def: the CIPSO DOI to use * @secattr: the specific security attributes of the socket * * Description: * Set the CIPSO option on the given socket using the DOI definition and * security attributes passed to the function. Returns zero on success and * negative values on failure. * */ int cipso_v4_req_setattr(struct request_sock *req, const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_delopt - Delete the CIPSO option from a set of IP options * @opt_ptr: IP option pointer * * Description: * Deletes the CIPSO IP option from a set of IP options and makes the necessary * adjustments to the IP option structure. Returns zero on success, negative * values on failure. * */ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) { … } /** * cipso_v4_sock_delattr - Delete the CIPSO option from a socket * @sk: the socket * * Description: * Removes the CIPSO option from a socket, if present. * */ void cipso_v4_sock_delattr(struct sock *sk) { … } /** * cipso_v4_req_delattr - Delete the CIPSO option from a request socket * @req: the request socket * * Description: * Removes the CIPSO option from a request socket, if present. * */ void cipso_v4_req_delattr(struct request_sock *req) { … } /** * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions * @cipso: the CIPSO v4 option * @secattr: the security attributes * * Description: * Inspect @cipso and return the security attributes in @secattr. Returns zero * on success and negative values on failure. * */ int cipso_v4_getattr(const unsigned char *cipso, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_sock_getattr - Get the security attributes from a sock * @sk: the sock * @secattr: the security attributes * * Description: * Query @sk to see if there is a CIPSO option attached to the sock and if * there is return the CIPSO security attributes in @secattr. This function * requires that @sk be locked, or privately held, but it does not do any * locking itself. Returns zero on success and negative values on failure. * */ int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet * @skb: the packet * @doi_def: the DOI structure * @secattr: the security attributes * * Description: * Set the CIPSO option on the given packet based on the security attributes. * Returns a pointer to the IP header on success and NULL on failure. * */ int cipso_v4_skbuff_setattr(struct sk_buff *skb, const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr) { … } /** * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet * @skb: the packet * * Description: * Removes any and all CIPSO options from the given packet. Returns zero on * success, negative values on failure. * */ int cipso_v4_skbuff_delattr(struct sk_buff *skb) { … } /* * Setup Functions */ /** * cipso_v4_init - Initialize the CIPSO module * * Description: * Initialize the CIPSO module and prepare it for use. Returns zero on success * and negative values on failure. * */ static int __init cipso_v4_init(void) { … } subsys_initcall(cipso_v4_init);