From fcd48280643e92ec6cb29a04e9079dd7b6b5bfef Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Mon, 25 Sep 2006 15:56:09 -0700 Subject: [NetLabel]: rework the Netlink attribute handling (part 1) At the suggestion of Thomas Graf, rewrite NetLabel's use of Netlink attributes to better follow the common Netlink attribute usage. Signed-off-by: Paul Moore Signed-off-by: David S. Miller --- net/netlabel/netlabel_domainhash.c | 183 ++++++++----------------------------- net/netlabel/netlabel_domainhash.h | 6 +- net/netlabel/netlabel_user.c | 82 ----------------- net/netlabel/netlabel_user.h | 141 +--------------------------- 4 files changed, 43 insertions(+), 369 deletions(-) (limited to 'net/netlabel') diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c index 0489a137810..f56d7a8ac7b 100644 --- a/net/netlabel/netlabel_domainhash.c +++ b/net/netlabel/netlabel_domainhash.c @@ -354,160 +354,51 @@ struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain) } /** - * netlbl_domhsh_dump - Dump the domain hash table into a sk_buff + * netlbl_domhsh_walk - Iterate through the domain mapping hash table + * @skip_bkt: the number of buckets to skip at the start + * @skip_chain: the number of entries to skip in the first iterated bucket + * @callback: callback for each entry + * @cb_arg: argument for the callback function * * Description: - * Dump the domain hash table into a buffer suitable for returning to an - * application in response to a NetLabel management DOMAIN message. This - * function may fail if another process is growing the hash table at the same - * time. The returned sk_buff has room at the front of the sk_buff for - * @headroom bytes. See netlabel.h for the DOMAIN message format. Returns a - * pointer to a sk_buff on success, NULL on error. + * Interate over the domain mapping hash table, skipping the first @skip_bkt + * buckets and @skip_chain entries. For each entry in the table call + * @callback, if @callback returns a negative value stop 'walking' through the + * table and return. Updates the values in @skip_bkt and @skip_chain on + * return. Returns zero on succcess, negative values on failure. * */ -struct sk_buff *netlbl_domhsh_dump(size_t headroom) +int netlbl_domhsh_walk(u32 *skip_bkt, + u32 *skip_chain, + int (*callback) (struct netlbl_dom_map *entry, void *arg), + void *cb_arg) { - struct sk_buff *skb = NULL; - ssize_t buf_len; - u32 bkt_iter; - u32 dom_cnt = 0; - struct netlbl_domhsh_tbl *hsh_tbl; - struct netlbl_dom_map *list_iter; - ssize_t tmp_len; + int ret_val = -ENOENT; + u32 iter_bkt; + struct netlbl_dom_map *iter_entry; + u32 chain_cnt = 0; - buf_len = NETLBL_LEN_U32; rcu_read_lock(); - hsh_tbl = rcu_dereference(netlbl_domhsh); - for (bkt_iter = 0; bkt_iter < hsh_tbl->size; bkt_iter++) - list_for_each_entry_rcu(list_iter, - &hsh_tbl->tbl[bkt_iter], list) { - buf_len += NETLBL_LEN_U32 + - nla_total_size(strlen(list_iter->domain) + 1); - switch (list_iter->type) { - case NETLBL_NLTYPE_UNLABELED: - break; - case NETLBL_NLTYPE_CIPSOV4: - buf_len += 2 * NETLBL_LEN_U32; - break; - } - dom_cnt++; - } - - skb = netlbl_netlink_alloc_skb(headroom, buf_len, GFP_ATOMIC); - if (skb == NULL) - goto dump_failure; - - if (nla_put_u32(skb, NLA_U32, dom_cnt) != 0) - goto dump_failure; - buf_len -= NETLBL_LEN_U32; - hsh_tbl = rcu_dereference(netlbl_domhsh); - for (bkt_iter = 0; bkt_iter < hsh_tbl->size; bkt_iter++) - list_for_each_entry_rcu(list_iter, - &hsh_tbl->tbl[bkt_iter], list) { - tmp_len = nla_total_size(strlen(list_iter->domain) + - 1); - if (buf_len < NETLBL_LEN_U32 + tmp_len) - goto dump_failure; - if (nla_put_string(skb, - NLA_STRING, - list_iter->domain) != 0) - goto dump_failure; - if (nla_put_u32(skb, NLA_U32, list_iter->type) != 0) - goto dump_failure; - buf_len -= NETLBL_LEN_U32 + tmp_len; - switch (list_iter->type) { - case NETLBL_NLTYPE_UNLABELED: - break; - case NETLBL_NLTYPE_CIPSOV4: - if (buf_len < 2 * NETLBL_LEN_U32) - goto dump_failure; - if (nla_put_u32(skb, - NLA_U32, - list_iter->type_def.cipsov4->type) != 0) - goto dump_failure; - if (nla_put_u32(skb, - NLA_U32, - list_iter->type_def.cipsov4->doi) != 0) - goto dump_failure; - buf_len -= 2 * NETLBL_LEN_U32; - break; + for (iter_bkt = *skip_bkt; + iter_bkt < rcu_dereference(netlbl_domhsh)->size; + iter_bkt++, chain_cnt = 0) { + list_for_each_entry_rcu(iter_entry, + &netlbl_domhsh->tbl[iter_bkt], + list) + if (iter_entry->valid) { + if (chain_cnt++ < *skip_chain) + continue; + ret_val = callback(iter_entry, cb_arg); + if (ret_val < 0) { + chain_cnt--; + goto walk_return; + } } - } - rcu_read_unlock(); - - return skb; - -dump_failure: - rcu_read_unlock(); - kfree_skb(skb); - return NULL; -} - -/** - * netlbl_domhsh_dump_default - Dump the default domain mapping into a sk_buff - * - * Description: - * Dump the default domain mapping into a buffer suitable for returning to an - * application in response to a NetLabel management DEFDOMAIN message. This - * function may fail if another process is changing the default domain mapping - * at the same time. The returned sk_buff has room at the front of the - * skb_buff for @headroom bytes. See netlabel.h for the DEFDOMAIN message - * format. Returns a pointer to a sk_buff on success, NULL on error. - * - */ -struct sk_buff *netlbl_domhsh_dump_default(size_t headroom) -{ - struct sk_buff *skb; - ssize_t buf_len; - struct netlbl_dom_map *entry; - - buf_len = NETLBL_LEN_U32; - rcu_read_lock(); - entry = rcu_dereference(netlbl_domhsh_def); - if (entry != NULL) - switch (entry->type) { - case NETLBL_NLTYPE_UNLABELED: - break; - case NETLBL_NLTYPE_CIPSOV4: - buf_len += 2 * NETLBL_LEN_U32; - break; - } - - skb = netlbl_netlink_alloc_skb(headroom, buf_len, GFP_ATOMIC); - if (skb == NULL) - goto dump_default_failure; - - if (entry != rcu_dereference(netlbl_domhsh_def)) - goto dump_default_failure; - if (entry != NULL) { - if (nla_put_u32(skb, NLA_U32, entry->type) != 0) - goto dump_default_failure; - buf_len -= NETLBL_LEN_U32; - switch (entry->type) { - case NETLBL_NLTYPE_UNLABELED: - break; - case NETLBL_NLTYPE_CIPSOV4: - if (buf_len < 2 * NETLBL_LEN_U32) - goto dump_default_failure; - if (nla_put_u32(skb, - NLA_U32, - entry->type_def.cipsov4->type) != 0) - goto dump_default_failure; - if (nla_put_u32(skb, - NLA_U32, - entry->type_def.cipsov4->doi) != 0) - goto dump_default_failure; - buf_len -= 2 * NETLBL_LEN_U32; - break; - } - } else - nla_put_u32(skb, NLA_U32, NETLBL_NLTYPE_NONE); - rcu_read_unlock(); - - return skb; + } -dump_default_failure: +walk_return: rcu_read_unlock(); - kfree_skb(skb); - return NULL; + *skip_bkt = iter_bkt; + *skip_chain = chain_cnt; + return ret_val; } diff --git a/net/netlabel/netlabel_domainhash.h b/net/netlabel/netlabel_domainhash.h index 99a2287de24..02af72a7877 100644 --- a/net/netlabel/netlabel_domainhash.h +++ b/net/netlabel/netlabel_domainhash.h @@ -61,7 +61,9 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry); int netlbl_domhsh_add_default(struct netlbl_dom_map *entry); int netlbl_domhsh_remove_default(void); struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain); -struct sk_buff *netlbl_domhsh_dump(size_t headroom); -struct sk_buff *netlbl_domhsh_dump_default(size_t headroom); +int netlbl_domhsh_walk(u32 *skip_bkt, + u32 *skip_chain, + int (*callback) (struct netlbl_dom_map *entry, void *arg), + void *cb_arg); #endif diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c index 73cbe66e42f..eeb7d768d2b 100644 --- a/net/netlabel/netlabel_user.c +++ b/net/netlabel/netlabel_user.c @@ -74,85 +74,3 @@ int netlbl_netlink_init(void) return 0; } - -/* - * NetLabel Common Protocol Functions - */ - -/** - * netlbl_netlink_send_ack - Send an ACK message - * @info: the generic NETLINK information - * @genl_family: the generic NETLINK family ID value - * @ack_cmd: the generic NETLINK family ACK command value - * @ret_code: return code to use - * - * Description: - * This function sends an ACK message to the sender of the NETLINK message - * specified by @info. - * - */ -void netlbl_netlink_send_ack(const struct genl_info *info, - u32 genl_family, - u8 ack_cmd, - u32 ret_code) -{ - size_t data_size; - struct sk_buff *skb; - - data_size = GENL_HDRLEN + 2 * NETLBL_LEN_U32; - skb = netlbl_netlink_alloc_skb(0, data_size, GFP_KERNEL); - if (skb == NULL) - return; - - if (netlbl_netlink_hdr_put(skb, - info->snd_pid, - 0, - genl_family, - ack_cmd) == NULL) - goto send_ack_failure; - - if (nla_put_u32(skb, NLA_U32, info->snd_seq) != 0) - goto send_ack_failure; - if (nla_put_u32(skb, NLA_U32, ret_code) != 0) - goto send_ack_failure; - - netlbl_netlink_snd(skb, info->snd_pid); - return; - -send_ack_failure: - kfree_skb(skb); -} - -/* - * NETLINK I/O Functions - */ - -/** - * netlbl_netlink_snd - Send a NetLabel message - * @skb: NetLabel message - * @pid: destination PID - * - * Description: - * Sends a unicast NetLabel message over the NETLINK socket. - * - */ -int netlbl_netlink_snd(struct sk_buff *skb, u32 pid) -{ - return genlmsg_unicast(skb, pid); -} - -/** - * netlbl_netlink_snd - Send a NetLabel message - * @skb: NetLabel message - * @pid: sending PID - * @group: multicast group id - * - * Description: - * Sends a multicast NetLabel message over the NETLINK socket to all members - * of @group except @pid. - * - */ -int netlbl_netlink_snd_multicast(struct sk_buff *skb, u32 pid, u32 group) -{ - return genlmsg_multicast(skb, pid, group, GFP_KERNEL); -} diff --git a/net/netlabel/netlabel_user.h b/net/netlabel/netlabel_user.h index 385a6c7488c..3f9386b917d 100644 --- a/net/netlabel/netlabel_user.h +++ b/net/netlabel/netlabel_user.h @@ -40,72 +40,6 @@ /* NetLabel NETLINK helper functions */ -/** - * netlbl_netlink_cap_check - Check the NETLINK msg capabilities - * @skb: the NETLINK buffer - * @req_cap: the required capability - * - * Description: - * Check the NETLINK buffer's capabilities against the required capabilities. - * Returns zero on success, negative values on failure. - * - */ -static inline int netlbl_netlink_cap_check(const struct sk_buff *skb, - kernel_cap_t req_cap) -{ - if (cap_raised(NETLINK_CB(skb).eff_cap, req_cap)) - return 0; - return -EPERM; -} - -/** - * netlbl_getinc_u8 - Read a u8 value from a nlattr stream and move on - * @nla: the attribute - * @rem_len: remaining length - * - * Description: - * Return a u8 value pointed to by @nla and advance it to the next attribute. - * - */ -static inline u8 netlbl_getinc_u8(struct nlattr **nla, int *rem_len) -{ - u8 val = nla_get_u8(*nla); - *nla = nla_next(*nla, rem_len); - return val; -} - -/** - * netlbl_getinc_u16 - Read a u16 value from a nlattr stream and move on - * @nla: the attribute - * @rem_len: remaining length - * - * Description: - * Return a u16 value pointed to by @nla and advance it to the next attribute. - * - */ -static inline u16 netlbl_getinc_u16(struct nlattr **nla, int *rem_len) -{ - u16 val = nla_get_u16(*nla); - *nla = nla_next(*nla, rem_len); - return val; -} - -/** - * netlbl_getinc_u32 - Read a u32 value from a nlattr stream and move on - * @nla: the attribute - * @rem_len: remaining length - * - * Description: - * Return a u32 value pointed to by @nla and advance it to the next attribute. - * - */ -static inline u32 netlbl_getinc_u32(struct nlattr **nla, int *rem_len) -{ - u32 val = nla_get_u32(*nla); - *nla = nla_next(*nla, rem_len); - return val; -} - /** * netlbl_netlink_hdr_put - Write the NETLINK buffers into a sk_buff * @skb: the packet @@ -124,6 +58,7 @@ static inline void *netlbl_netlink_hdr_put(struct sk_buff *skb, u32 pid, u32 seq, int type, + int flags, u8 cmd) { return genlmsg_put(skb, @@ -131,85 +66,13 @@ static inline void *netlbl_netlink_hdr_put(struct sk_buff *skb, seq, type, 0, - 0, + flags, cmd, NETLBL_PROTO_VERSION); } -/** - * netlbl_netlink_hdr_push - Write the NETLINK buffers into a sk_buff - * @skb: the packet - * @pid: the PID of the receipient - * @seq: the sequence number - * @type: the generic NETLINK message family type - * @cmd: command - * - * Description: - * Write both a NETLINK nlmsghdr structure and a Generic NETLINK genlmsghdr - * struct to the packet. - * - */ -static inline void netlbl_netlink_hdr_push(struct sk_buff *skb, - u32 pid, - u32 seq, - int type, - u8 cmd) - -{ - struct nlmsghdr *nlh; - struct genlmsghdr *hdr; - - nlh = (struct nlmsghdr *)skb_push(skb, NLMSG_SPACE(GENL_HDRLEN)); - nlh->nlmsg_type = type; - nlh->nlmsg_len = skb->len; - nlh->nlmsg_flags = 0; - nlh->nlmsg_pid = pid; - nlh->nlmsg_seq = seq; - - hdr = nlmsg_data(nlh); - hdr->cmd = cmd; - hdr->version = NETLBL_PROTO_VERSION; - hdr->reserved = 0; -} - -/** - * netlbl_netlink_payload_len - Return the length of the payload - * @skb: the NETLINK buffer - * - * Description: - * This function returns the length of the NetLabel payload. - * - */ -static inline u32 netlbl_netlink_payload_len(const struct sk_buff *skb) -{ - return nlmsg_len((struct nlmsghdr *)skb->data) - GENL_HDRLEN; -} - -/** - * netlbl_netlink_payload_data - Returns a pointer to the start of the payload - * @skb: the NETLINK buffer - * - * Description: - * This function returns a pointer to the start of the NetLabel payload. - * - */ -static inline void *netlbl_netlink_payload_data(const struct sk_buff *skb) -{ - return (unsigned char *)nlmsg_data((struct nlmsghdr *)skb->data) + - GENL_HDRLEN; -} - -/* NetLabel common protocol functions */ - -void netlbl_netlink_send_ack(const struct genl_info *info, - u32 genl_family, - u8 ack_cmd, - u32 ret_code); - /* NetLabel NETLINK I/O functions */ int netlbl_netlink_init(void); -int netlbl_netlink_snd(struct sk_buff *skb, u32 pid); -int netlbl_netlink_snd_multicast(struct sk_buff *skb, u32 pid, u32 group); #endif -- cgit v1.2.3-18-g5258