From d2a0036dd3e16d40f4039a11677241827ea057c5 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sat, 2 Feb 2013 12:17:31 +0100 Subject: set: add support to add elements to sets This patch includes iterators and several examples. Signed-off-by: Pablo Neira Ayuso --- src/Makefile.am | 1 + src/internal.h | 27 ++++ src/libnftables.map | 22 +++ src/set.c | 41 +++--- src/set_elem.c | 399 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 472 insertions(+), 18 deletions(-) create mode 100644 src/set_elem.c (limited to 'src') diff --git a/src/Makefile.am b/src/Makefile.am index d14251a..7e51104 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -8,6 +8,7 @@ libnftables_la_SOURCES = table.c \ chain.c \ rule.c \ set.c \ + set_elem.c \ expr.c \ expr_ops.c \ expr/bitwise.c \ diff --git a/src/internal.h b/src/internal.h index 5ba7c76..f5717ed 100644 --- a/src/internal.h +++ b/src/internal.h @@ -22,6 +22,33 @@ struct nft_rule_expr { uint8_t data[]; }; +struct nlattr; + +struct nft_set { + struct list_head head; + + uint32_t set_flags; + char *table; + char *name; + uint32_t key_type; + size_t key_len; + uint32_t data_type; + size_t data_len; + struct list_head element_list; + + uint32_t flags; +}; + +#include "expr/data_reg.h" + +struct nft_set_elem { + struct list_head head; + uint32_t set_elem_flags; + union nft_data_reg key; + union nft_data_reg data; + uint32_t flags; +}; + #define SNPRINTF_BUFFER_SIZE(ret, size, len, offset) \ size += ret; \ if (ret > len) \ diff --git a/src/libnftables.map b/src/libnftables.map index 6fc316f..957e3b6 100644 --- a/src/libnftables.map +++ b/src/libnftables.map @@ -104,5 +104,27 @@ global: nft_set_list_iter_next; nft_set_list_iter_destroy; + nft_set_elem_alloc; + nft_set_elem_free; + nft_set_elem_add; + nft_set_elem_attr_set; + nft_set_elem_attr_set_u32; + nft_set_elem_attr_set_str; + nft_set_elem_attr_get; + nft_set_elem_attr_get_str; + nft_set_elem_attr_get_u32; + nft_set_elem_nlmsg_build_hdr; + nft_set_elem_nlmsg_build_payload; + nft_set_elem_nlmsg_parse; + nft_set_elem_snprintf; + + nft_set_elems_nlmsg_build_payload; + nft_set_elems_nlmsg_parse; + + nft_set_elems_iter_create; + nft_set_elems_iter_cur; + nft_set_elems_iter_next; + nft_set_elems_iter_destroy; + local: *; }; diff --git a/src/set.c b/src/set.c index 54cc55d..f285b34 100644 --- a/src/set.c +++ b/src/set.c @@ -26,20 +26,6 @@ #include "linux_list.h" #include "expr/data_reg.h" -struct nft_set { - struct list_head head; - - uint32_t set_flags; - char *table; - char *name; - uint32_t key_type; - size_t key_len; - uint32_t data_type; - size_t data_len; - - uint32_t flags; -}; - struct nft_set *nft_set_alloc(void) { struct nft_set *s; @@ -48,17 +34,24 @@ struct nft_set *nft_set_alloc(void) if (s == NULL) return NULL; + INIT_LIST_HEAD(&s->element_list); return s; } EXPORT_SYMBOL(nft_set_alloc); void nft_set_free(struct nft_set *s) { + struct nft_set_elem *elem, *tmp; + if (s->table != NULL) free(s->table); if (s->name != NULL) free(s->name); + list_for_each_entry_safe(elem, tmp, &s->element_list, head) { + list_del(&elem->head); + nft_set_elem_free(elem); + } free(s); } EXPORT_SYMBOL(nft_set_free); @@ -275,18 +268,30 @@ int nft_set_snprintf(char *buf, size_t size, struct nft_set *s, { int ret; int len = size, offset = 0; + struct nft_set_elem *elem; - ret = snprintf(buf, size, "set=%s table=%s flags=%x ", + ret = snprintf(buf, size, "set=%s table=%s flags=%x\n", s->name, s->table, s->set_flags); SNPRINTF_BUFFER_SIZE(ret, size, len, offset); - ret = snprintf(buf+offset-1, len, "\n"); - SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + list_for_each_entry(elem, &s->element_list, head) { + ret = snprintf(buf+offset, size, "\t"); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); - return ret; + ret = nft_set_elem_snprintf(buf+offset, size, elem, type, flags); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + + return offset; } EXPORT_SYMBOL(nft_set_snprintf); +void nft_set_elem_add(struct nft_set *s, struct nft_set_elem *elem) +{ + list_add_tail(&elem->head, &s->element_list); +} +EXPORT_SYMBOL(nft_set_elem_add); + struct nft_set_list { struct list_head list; }; diff --git a/src/set_elem.c b/src/set_elem.c new file mode 100644 index 0000000..980faed --- /dev/null +++ b/src/set_elem.c @@ -0,0 +1,399 @@ +/* + * (C) 2012-2013 by Pablo Neira Ayuso + * + * 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. + * + * This code has been sponsored by Sophos Astaro + */ +#include "internal.h" + +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include + +#include "linux_list.h" +#include "expr/data_reg.h" + +struct nft_set_elem *nft_set_elem_alloc(void) +{ + struct nft_set_elem *s; + + s = calloc(1, sizeof(struct nft_set_elem)); + if (s == NULL) + return NULL; + + return s; +} +EXPORT_SYMBOL(nft_set_elem_alloc); + +void nft_set_elem_free(struct nft_set_elem *s) +{ + free(s); +} +EXPORT_SYMBOL(nft_set_elem_free); + +void nft_set_elem_attr_set(struct nft_set_elem *s, uint16_t attr, + const void *data, size_t data_len) +{ + switch(attr) { + case NFT_SET_ELEM_ATTR_FLAGS: + s->set_elem_flags = *((uint32_t *)data); + break; + case NFT_SET_ELEM_ATTR_KEY: /* NFTA_SET_ELEM_KEY */ + memcpy(&s->key.val, data, data_len); + s->key.len = data_len; + break; + case NFT_SET_ELEM_ATTR_VERDICT: /* NFTA_SET_ELEM_DATA */ + s->data.verdict = *((uint32_t *)data); + break; + case NFT_SET_ELEM_ATTR_CHAIN: /* NFTA_SET_ELEM_DATA */ + if (s->data.chain) + free(s->data.chain); + + s->data.chain = strdup(data); + break; + default: + return; + } + s->flags |= (1 << attr); +} +EXPORT_SYMBOL(nft_set_elem_attr_set); + +void nft_set_elem_attr_set_u32(struct nft_set_elem *s, uint16_t attr, uint32_t val) +{ + nft_set_elem_attr_set(s, attr, &val, sizeof(uint32_t)); +} +EXPORT_SYMBOL(nft_set_elem_attr_set_u32); + +void *nft_set_elem_attr_get(struct nft_set_elem *s, uint16_t attr, size_t *data_len) +{ + switch(attr) { + case NFT_SET_ELEM_ATTR_FLAGS: + if (s->flags & (1 << NFT_SET_ELEM_ATTR_FLAGS)) + return &s->set_elem_flags; + break; + case NFT_SET_ELEM_ATTR_KEY: /* NFTA_SET_ELEM_KEY */ + if (s->flags & (1 << NFT_SET_ELEM_ATTR_KEY)) { + *data_len = s->key.len; + return &s->key.val; + } + break; + case NFT_SET_ELEM_ATTR_VERDICT: /* NFTA_SET_ELEM_DATA */ + if (s->flags & (1 << NFT_SET_ELEM_ATTR_VERDICT)) + return &s->data.verdict; + break; + case NFT_SET_ELEM_ATTR_CHAIN: /* NFTA_SET_ELEM_DATA */ + if (s->flags & (1 << NFT_SET_ELEM_ATTR_CHAIN)) + return &s->data.chain; + break; + default: + break; + } + return NULL; +} +EXPORT_SYMBOL(nft_set_elem_attr_get); + +const char *nft_set_elem_attr_get_str(struct nft_set_elem *s, uint16_t attr) +{ + size_t size; + + return nft_set_elem_attr_get(s, attr, &size); +} +EXPORT_SYMBOL(nft_set_elem_attr_get_str); + +uint32_t nft_set_elem_attr_get_u32(struct nft_set_elem *s, uint16_t attr) +{ + size_t size; + uint32_t val = *((uint32_t *)nft_set_elem_attr_get(s, attr, &size)); + return val; +} +EXPORT_SYMBOL(nft_set_elem_attr_get_u32); + +struct nlmsghdr * +nft_set_elem_nlmsg_build_hdr(char *buf, uint16_t cmd, uint16_t family, + uint16_t type, uint32_t seq) +{ + struct nlmsghdr *nlh; + struct nfgenmsg *nfh; + + nlh = mnl_nlmsg_put_header(buf); + nlh->nlmsg_type = (NFNL_SUBSYS_NFTABLES << 8) | cmd; + nlh->nlmsg_flags = NLM_F_REQUEST | type; + nlh->nlmsg_seq = seq; + + nfh = mnl_nlmsg_put_extra_header(nlh, sizeof(struct nfgenmsg)); + nfh->nfgen_family = family; + nfh->version = NFNETLINK_V0; + nfh->res_id = 0; + + return nlh; +} +EXPORT_SYMBOL(nft_set_elem_nlmsg_build_hdr); + +void nft_set_elem_nlmsg_build_payload(struct nlmsghdr *nlh, + struct nft_set_elem *e) +{ + if (e->flags & (1 << NFT_SET_ELEM_ATTR_FLAGS)) + mnl_attr_put_u32(nlh, NFTA_SET_ELEM_FLAGS, htonl(e->set_elem_flags)); + if (e->flags & (1 << NFT_SET_ELEM_ATTR_KEY)) { + struct nlattr *nest1; + + nest1 = mnl_attr_nest_start(nlh, NFTA_SET_ELEM_KEY); + mnl_attr_put(nlh, NFTA_DATA_VALUE, e->key.len, e->key.val); + mnl_attr_nest_end(nlh, nest1); + } + if (e->flags & (1 << NFT_SET_ELEM_ATTR_VERDICT)) { + struct nlattr *nest1, *nest2; + + nest1 = mnl_attr_nest_start(nlh, NFTA_SET_ELEM_DATA); + nest2 = mnl_attr_nest_start(nlh, NFTA_DATA_VERDICT); + mnl_attr_put_u32(nlh, NFTA_VERDICT_CODE, htonl(e->data.verdict)); + if (e->flags & (1 << NFT_SET_ELEM_ATTR_CHAIN)) + mnl_attr_put_strz(nlh, NFTA_VERDICT_CHAIN, e->data.chain); + + mnl_attr_nest_end(nlh, nest1); + mnl_attr_nest_end(nlh, nest2); + } +} + +void nft_set_elems_nlmsg_build_payload(struct nlmsghdr *nlh, struct nft_set *s) +{ + struct nft_set_elem *elem; + struct nlattr *nest1; + int i = 0; + + if (s->flags & (1 << NFT_SET_ATTR_NAME)) + mnl_attr_put_strz(nlh, NFTA_SET_ELEM_LIST_SET, s->name); + if (s->flags & (1 << NFT_SET_ATTR_TABLE)) + mnl_attr_put_strz(nlh, NFTA_SET_ELEM_LIST_TABLE, s->table); + + nest1 = mnl_attr_nest_start(nlh, NFTA_SET_ELEM_LIST_ELEMENTS); + list_for_each_entry(elem, &s->element_list, head) { + struct nlattr *nest2; + + nest2 = mnl_attr_nest_start(nlh, ++i); + nft_set_elem_nlmsg_build_payload(nlh, elem); + mnl_attr_nest_end(nlh, nest2); + } + mnl_attr_nest_end(nlh, nest1); +} +EXPORT_SYMBOL(nft_set_elems_nlmsg_build_payload); + +static int nft_set_elem_parse_attr_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_SET_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_SET_ELEM_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + case NFTA_SET_ELEM_KEY: + case NFTA_SET_ELEM_DATA: + if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static int nft_set_elems_parse2(struct nft_set *s, const struct nlattr *nest) +{ + struct nlattr *tb[NFTA_SET_ELEM_MAX+1] = {}; + struct nft_set_elem *e; + int ret = 0, type; + + e = nft_set_elem_alloc(); + if (e == NULL) + return -1; + + mnl_attr_parse_nested(nest, nft_set_elem_parse_attr_cb, tb); + if (tb[NFTA_SET_ELEM_FLAGS]) { + e->set_elem_flags = + ntohl(mnl_attr_get_u32(tb[NFTA_SET_ELEM_FLAGS])); + e->flags |= (1 << NFT_SET_ELEM_ATTR_KEY); + } + if (tb[NFTA_SET_ELEM_KEY]) { + ret = nft_parse_data(&e->key, tb[NFTA_SET_ELEM_KEY], &type); + e->flags |= (1 << NFT_SET_ELEM_ATTR_KEY); + } + if (tb[NFTA_SET_ELEM_DATA]) { + ret = nft_parse_data(&e->data, tb[NFTA_SET_ELEM_DATA], &type); + switch(type) { + case DATA_VERDICT: + s->flags |= (1 << NFT_SET_ELEM_ATTR_VERDICT); + break; + case DATA_CHAIN: + s->flags |= (1 << NFT_SET_ELEM_ATTR_CHAIN); + break; + } + } + if (ret < 0) + free(e); + + /* Add this new element to this set */ + list_add_tail(&e->head, &s->element_list); + + return ret; +} +EXPORT_SYMBOL(nft_set_elem_nlmsg_parse); + +static int +nft_set_elem_list_parse_attr_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_SET_ELEM_LIST_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_SET_ELEM_LIST_TABLE: + case NFTA_SET_ELEM_LIST_SET: + if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + case NFTA_SET_ELEM_LIST_ELEMENTS: + if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static int nft_set_elems_parse(struct nft_set *s, const struct nlattr *nest) +{ + struct nlattr *attr; + int ret = 0; + + mnl_attr_for_each_nested(attr, nest) { + if (mnl_attr_get_type(attr) != NFTA_LIST_ELEM) + return -1; + + ret = nft_set_elems_parse2(s, attr); + } + return ret; +} + +int nft_set_elems_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_set *s) +{ + struct nlattr *tb[NFTA_SET_ELEM_LIST_MAX+1] = {}; + struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh); + int ret = 0; + + mnl_attr_parse(nlh, sizeof(*nfg), nft_set_elem_list_parse_attr_cb, tb); + if (tb[NFTA_SET_ELEM_LIST_TABLE]) { + s->table = + strdup(mnl_attr_get_str(tb[NFTA_SET_ELEM_LIST_TABLE])); + s->flags |= (1 << NFT_SET_ATTR_TABLE); + } + if (tb[NFTA_SET_ELEM_LIST_SET]) { + s->name = + strdup(mnl_attr_get_str(tb[NFTA_SET_ELEM_LIST_SET])); + s->flags |= (1 << NFT_SET_ATTR_NAME); + } + if (tb[NFTA_SET_ELEM_LIST_ELEMENTS]) + ret = nft_set_elems_parse(s, tb[NFTA_SET_ELEM_LIST_ELEMENTS]); + + return ret; +} +EXPORT_SYMBOL(nft_set_elems_nlmsg_parse); + +int nft_set_elem_snprintf(char *buf, size_t size, struct nft_set_elem *e, + uint32_t type, uint32_t flags) +{ + int ret, len = size, offset = 0, i; + + ret = snprintf(buf, size, "flags=%u key=", e->set_elem_flags); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + for (i=0; ikey.len/sizeof(uint32_t); i++) { + ret = snprintf(buf+offset, len, "%.8x ", e->key.val[i]); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + + ret = snprintf(buf+offset, size, "data="); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + for (i=0; idata.len/sizeof(uint32_t); i++) { + ret = snprintf(buf+offset, len, "%.8x ", e->data.val[i]); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + ret = snprintf(buf+offset, size, "\n"); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + return offset; +} +EXPORT_SYMBOL(nft_set_elem_snprintf); + +struct nft_set_elems_iter { + struct list_head *list; + struct nft_set_elem *cur; +}; + +struct nft_set_elems_iter *nft_set_elems_iter_create(struct nft_set *s) +{ + struct nft_set_elems_iter *iter; + + iter = calloc(1, sizeof(struct nft_set_elems_iter)); + if (iter == NULL) + return NULL; + + iter->list = &s->element_list; + iter->cur = list_entry(s->element_list.next, struct nft_set_elem, head); + + return iter; +} +EXPORT_SYMBOL(nft_set_elems_iter_create); + +struct nft_set_elem *nft_set_elems_iter_cur(struct nft_set_elems_iter *iter) +{ + return iter->cur; +} +EXPORT_SYMBOL(nft_set_elems_iter_cur); + +struct nft_set_elem *nft_set_elems_iter_next(struct nft_set_elems_iter *iter) +{ + struct nft_set_elem *s = iter->cur; + + iter->cur = list_entry(iter->cur->head.next, struct nft_set_elem, head); + if (&iter->cur->head == iter->list->next) + return NULL; + + return s; +} +EXPORT_SYMBOL(nft_set_elems_iter_next); + +void nft_set_elems_iter_destroy(struct nft_set_elems_iter *iter) +{ + free(iter); +} +EXPORT_SYMBOL(nft_set_elems_iter_destroy); -- cgit v1.2.3