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/ipv4/cipso_ipv4.c | 203 ++++++-------------------------------------------- 1 file changed, 24 insertions(+), 179 deletions(-) (limited to 'net/ipv4/cipso_ipv4.c') diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index 87e71563335..e6ce0b3ba62 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -530,197 +530,42 @@ struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi) } /** - * cipso_v4_doi_dump_all - Dump all the CIPSO DOI definitions into a sk_buff - * @headroom: the amount of headroom to allocate for the sk_buff + * 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: - * Dump a list of all the configured DOI values into a sk_buff. The returned - * sk_buff has room at the front of the sk_buff for @headroom bytes. See - * net/netlabel/netlabel_cipso_v4.h for the LISTALL message format. This - * function may fail if another process is changing the DOI list at the same - * time. Returns a pointer to a sk_buff on success, NULL on error. + * 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. * */ -struct sk_buff *cipso_v4_doi_dump_all(size_t headroom) +int cipso_v4_doi_walk(u32 *skip_cnt, + int (*callback) (struct cipso_v4_doi *doi_def, void *arg), + void *cb_arg) { - struct sk_buff *skb = NULL; - struct cipso_v4_doi *iter; + int ret_val = -ENOENT; u32 doi_cnt = 0; - ssize_t buf_len; - - buf_len = NETLBL_LEN_U32; - rcu_read_lock(); - list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) - if (iter->valid) { - doi_cnt += 1; - buf_len += 2 * NETLBL_LEN_U32; - } - - skb = netlbl_netlink_alloc_skb(headroom, buf_len, GFP_ATOMIC); - if (skb == NULL) - goto doi_dump_all_failure; - - if (nla_put_u32(skb, NLA_U32, doi_cnt) != 0) - goto doi_dump_all_failure; - buf_len -= NETLBL_LEN_U32; - list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list) - if (iter->valid) { - if (buf_len < 2 * NETLBL_LEN_U32) - goto doi_dump_all_failure; - if (nla_put_u32(skb, NLA_U32, iter->doi) != 0) - goto doi_dump_all_failure; - if (nla_put_u32(skb, NLA_U32, iter->type) != 0) - goto doi_dump_all_failure; - buf_len -= 2 * NETLBL_LEN_U32; - } - rcu_read_unlock(); - - return skb; - -doi_dump_all_failure: - rcu_read_unlock(); - kfree(skb); - return NULL; -} - -/** - * cipso_v4_doi_dump - Dump a CIPSO DOI definition into a sk_buff - * @doi: the DOI value - * @headroom: the amount of headroom to allocate for the sk_buff - * - * Description: - * Lookup the DOI definition matching @doi and dump it's contents into a - * sk_buff. The returned sk_buff has room at the front of the sk_buff for - * @headroom bytes. See net/netlabel/netlabel_cipso_v4.h for the LIST message - * format. This function may fail if another process is changing the DOI list - * at the same time. Returns a pointer to a sk_buff on success, NULL on error. - * - */ -struct sk_buff *cipso_v4_doi_dump(u32 doi, size_t headroom) -{ - struct sk_buff *skb = NULL; - struct cipso_v4_doi *iter; - u32 tag_cnt = 0; - u32 lvl_cnt = 0; - u32 cat_cnt = 0; - ssize_t buf_len; - ssize_t tmp; + struct cipso_v4_doi *iter_doi; rcu_read_lock(); - iter = cipso_v4_doi_getdef(doi); - if (iter == NULL) - goto doi_dump_failure; - buf_len = NETLBL_LEN_U32; - switch (iter->type) { - case CIPSO_V4_MAP_PASS: - buf_len += NETLBL_LEN_U32; - while(tag_cnt < CIPSO_V4_TAG_MAXCNT && - iter->tags[tag_cnt] != CIPSO_V4_TAG_INVALID) { - tag_cnt += 1; - buf_len += NETLBL_LEN_U8; - } - break; - case CIPSO_V4_MAP_STD: - buf_len += 3 * NETLBL_LEN_U32; - while (tag_cnt < CIPSO_V4_TAG_MAXCNT && - iter->tags[tag_cnt] != CIPSO_V4_TAG_INVALID) { - tag_cnt += 1; - buf_len += NETLBL_LEN_U8; - } - for (tmp = 0; tmp < iter->map.std->lvl.local_size; tmp++) - if (iter->map.std->lvl.local[tmp] != - CIPSO_V4_INV_LVL) { - lvl_cnt += 1; - buf_len += NETLBL_LEN_U32 + NETLBL_LEN_U8; + list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list) + if (iter_doi->valid) { + if (doi_cnt++ < *skip_cnt) + continue; + ret_val = callback(iter_doi, cb_arg); + if (ret_val < 0) { + doi_cnt--; + goto doi_walk_return; } - for (tmp = 0; tmp < iter->map.std->cat.local_size; tmp++) - if (iter->map.std->cat.local[tmp] != - CIPSO_V4_INV_CAT) { - cat_cnt += 1; - buf_len += NETLBL_LEN_U32 + NETLBL_LEN_U16; - } - break; - } - - skb = netlbl_netlink_alloc_skb(headroom, buf_len, GFP_ATOMIC); - if (skb == NULL) - goto doi_dump_failure; - - if (nla_put_u32(skb, NLA_U32, iter->type) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U32; - if (iter != cipso_v4_doi_getdef(doi)) - goto doi_dump_failure; - switch (iter->type) { - case CIPSO_V4_MAP_PASS: - if (nla_put_u32(skb, NLA_U32, tag_cnt) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U32; - for (tmp = 0; - tmp < CIPSO_V4_TAG_MAXCNT && - iter->tags[tmp] != CIPSO_V4_TAG_INVALID; - tmp++) { - if (buf_len < NETLBL_LEN_U8) - goto doi_dump_failure; - if (nla_put_u8(skb, NLA_U8, iter->tags[tmp]) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U8; } - break; - case CIPSO_V4_MAP_STD: - if (nla_put_u32(skb, NLA_U32, tag_cnt) != 0) - goto doi_dump_failure; - if (nla_put_u32(skb, NLA_U32, lvl_cnt) != 0) - goto doi_dump_failure; - if (nla_put_u32(skb, NLA_U32, cat_cnt) != 0) - goto doi_dump_failure; - buf_len -= 3 * NETLBL_LEN_U32; - for (tmp = 0; - tmp < CIPSO_V4_TAG_MAXCNT && - iter->tags[tmp] != CIPSO_V4_TAG_INVALID; - tmp++) { - if (buf_len < NETLBL_LEN_U8) - goto doi_dump_failure; - if (nla_put_u8(skb, NLA_U8, iter->tags[tmp]) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U8; - } - for (tmp = 0; tmp < iter->map.std->lvl.local_size; tmp++) - if (iter->map.std->lvl.local[tmp] != - CIPSO_V4_INV_LVL) { - if (buf_len < NETLBL_LEN_U32 + NETLBL_LEN_U8) - goto doi_dump_failure; - if (nla_put_u32(skb, NLA_U32, tmp) != 0) - goto doi_dump_failure; - if (nla_put_u8(skb, - NLA_U8, - iter->map.std->lvl.local[tmp]) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U32 + NETLBL_LEN_U8; - } - for (tmp = 0; tmp < iter->map.std->cat.local_size; tmp++) - if (iter->map.std->cat.local[tmp] != - CIPSO_V4_INV_CAT) { - if (buf_len < NETLBL_LEN_U32 + NETLBL_LEN_U16) - goto doi_dump_failure; - if (nla_put_u32(skb, NLA_U32, tmp) != 0) - goto doi_dump_failure; - if (nla_put_u16(skb, - NLA_U16, - iter->map.std->cat.local[tmp]) != 0) - goto doi_dump_failure; - buf_len -= NETLBL_LEN_U32 + NETLBL_LEN_U16; - } - break; - } - rcu_read_unlock(); - - return skb; -doi_dump_failure: +doi_walk_return: rcu_read_unlock(); - kfree(skb); - return NULL; + *skip_cnt = doi_cnt; + return ret_val; } /** -- cgit v1.2.3