From ced050e74195c267d55e67a1c2ac5a591820d952 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 10 Jun 2013 19:23:03 +0200 Subject: expr: add log expression Signed-off-by: Pablo Neira Ayuso --- include/libnftables/expr.h | 7 ++ src/Makefile.am | 1 + src/expr/log.c | 281 +++++++++++++++++++++++++++++++++++++++++++++ src/expr_ops.c | 2 + 4 files changed, 291 insertions(+) create mode 100644 src/expr/log.c diff --git a/include/libnftables/expr.h b/include/libnftables/expr.h index 0592977..bddef6d 100644 --- a/include/libnftables/expr.h +++ b/include/libnftables/expr.h @@ -94,6 +94,13 @@ enum { NFT_EXPR_LOOKUP_SET, }; +enum { + NFT_EXPR_LOG_PREFIX = NFT_RULE_EXPR_ATTR_BASE, + NFT_EXPR_LOG_GROUP, + NFT_EXPR_LOG_SNAPLEN, + NFT_EXPR_LOG_QTHRESHOLD, +}; + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/src/Makefile.am b/src/Makefile.am index 8a61ce8..34339ab 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -15,6 +15,7 @@ libnftables_la_SOURCES = table.c \ expr/cmp.c \ expr/counter.c \ expr/data_reg.c \ + expr/log.c \ expr/lookup.c \ expr/immediate.c \ expr/match.c \ diff --git a/src/expr/log.c b/src/expr/log.c new file mode 100644 index 0000000..0e35a65 --- /dev/null +++ b/src/expr/log.c @@ -0,0 +1,281 @@ +/* + * (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 +#include +#include +#include +#include +#include + +#include "internal.h" +#include +#include +#include +#include "expr_ops.h" + +struct nft_expr_log { + uint32_t group; + uint32_t snaplen; + uint32_t qthreshold; + char *prefix; +}; + +static int +nft_rule_expr_log_set(struct nft_rule_expr *e, uint16_t type, + const void *data, size_t data_len) +{ + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + + switch(type) { + case NFT_EXPR_LOG_PREFIX: + if (log->prefix) + free(log->prefix); + + log->prefix = strdup(data); + break; + case NFT_EXPR_LOG_GROUP: + log->group = *((uint32_t *)data); + break; + case NFT_EXPR_LOG_SNAPLEN: + log->snaplen = *((uint32_t *)data); + break; + case NFT_EXPR_LOG_QTHRESHOLD: + log->qthreshold = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nft_rule_expr_log_get(struct nft_rule_expr *e, uint16_t type, size_t *data_len) +{ + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + + switch(type) { + case NFT_EXPR_LOG_PREFIX: + if (e->flags & (1 << NFT_EXPR_LOG_PREFIX)) + return log->prefix; + else + return NULL; + break; + case NFT_EXPR_LOG_GROUP: + if (e->flags & (1 << NFT_EXPR_LOG_GROUP)) + return &log->group; + else + return NULL; + break; + case NFT_EXPR_LOG_SNAPLEN: + if (e->flags & (1 << NFT_EXPR_LOG_SNAPLEN)) + return &log->snaplen; + else + return NULL; + break; + case NFT_EXPR_LOG_QTHRESHOLD: + if (e->flags & (1 << NFT_EXPR_LOG_QTHRESHOLD)) + return &log->qthreshold; + else + return NULL; + break; + default: + break; + } + return NULL; +} + +static int nft_rule_expr_log_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_LOG_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_LOG_PREFIX: + if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + case NFTA_LOG_GROUP: + case NFTA_LOG_SNAPLEN: + case NFTA_LOG_QTHRESHOLD: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nft_rule_expr_log_build(struct nlmsghdr *nlh, struct nft_rule_expr *e) +{ + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + + if (e->flags & (1 << NFT_EXPR_LOG_PREFIX)) + mnl_attr_put_str(nlh, NFTA_LOG_PREFIX, log->prefix); + if (e->flags & (1 << NFT_EXPR_LOG_GROUP)) + mnl_attr_put_u32(nlh, NFTA_LOG_GROUP, htonl(log->group)); + if (e->flags & (1 << NFT_EXPR_LOG_SNAPLEN)) + mnl_attr_put_u32(nlh, NFTA_LOG_SNAPLEN, htonl(log->snaplen)); + if (e->flags & (1 << NFT_EXPR_LOG_QTHRESHOLD)) + mnl_attr_put_u32(nlh, NFTA_LOG_QTHRESHOLD, htonl(log->qthreshold)); +} + +static int +nft_rule_expr_log_parse(struct nft_rule_expr *e, struct nlattr *attr) +{ + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + struct nlattr *tb[NFTA_LOG_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nft_rule_expr_log_cb, tb) < 0) + return -1; + + if (tb[NFTA_LOG_PREFIX]) { + if (log->prefix) + free(log->prefix); + + log->prefix = strdup(mnl_attr_get_str(tb[NFTA_LOG_PREFIX])); + e->flags |= (1 << NFT_EXPR_LOG_GROUP); + } + if (tb[NFTA_LOG_GROUP]) { + log->group = ntohl(mnl_attr_get_u32(tb[NFTA_LOG_GROUP])); + e->flags |= (1 << NFT_EXPR_LOG_GROUP); + } + if (tb[NFTA_LOG_SNAPLEN]) { + log->snaplen = ntohl(mnl_attr_get_u32(tb[NFTA_LOG_SNAPLEN])); + e->flags |= (1 << NFT_EXPR_LOG_SNAPLEN); + } + if (tb[NFTA_LOG_QTHRESHOLD]) { + log->qthreshold = ntohl(mnl_attr_get_u32(tb[NFTA_LOG_QTHRESHOLD])); + e->flags |= (1 << NFT_EXPR_LOG_QTHRESHOLD); + } + + return 0; +} + +static int nft_rule_expr_log_xml_parse(struct nft_rule_expr *e, char *xml) +{ +#ifdef XML_PARSING + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + mxml_node_t *tree = NULL; + mxml_node_t *node = NULL; + uint64_t tmp; + char *endptr; + + tree = mxmlLoadString(NULL, xml, MXML_OPAQUE_CALLBACK); + if (tree == NULL) + return -1; + + if (mxmlElementGetAttr(tree, "type") == NULL) + goto err; + + if (strcmp("log", mxmlElementGetAttr(tree, "type")) != 0) + goto err; + + node = mxmlFindElement(tree, tree, "prefix", NULL, NULL, + MXML_DESCEND_FIRST); + if (node == NULL) + goto err; + + log->prefix = strdup(node->child->value.opaque); + e->flags |= (1 << NFT_EXPR_LOG_PREFIX); + + node = mxmlFindElement(tree, tree, "group", NULL, NULL, MXML_DESCEND); + if (node == NULL) + goto err; + + tmp = strtoull(node->child->value.opaque, &endptr, 10); + if (tmp > UINT32_MAX || tmp < 0 || *endptr) + goto err; + + log->group = tmp; + e->flags |= (1 << NFT_EXPR_LOG_GROUP); + + node = mxmlFindElement(tree, tree, "snaplen", NULL, NULL, + MXML_DESCEND); + if (node == NULL) + goto err; + + tmp = strtoull(node->child->value.opaque, &endptr, 10); + if (tmp > UINT32_MAX || tmp < 0 || *endptr) + goto err; + + log->snaplen = tmp; + e->flags |= (1 << NFT_EXPR_LOG_SNAPLEN); + + node = mxmlFindElement(tree, tree, "qthreshold", NULL, NULL, + MXML_DESCEND); + if (node == NULL) + goto err; + + tmp = strtoull(node->child->value.opaque, &endptr, 10); + if (tmp > UINT32_MAX || tmp < 0 || *endptr) + goto err; + + log->qthreshold = tmp; + e->flags |= (1 << NFT_EXPR_LOG_QTHRESHOLD); + + mxmlDelete(tree); + return 0; +err: + errno = EINVAL; + mxmlDelete(tree); + return -1; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + +static int +nft_rule_expr_log_snprintf(char *buf, size_t len, uint32_t type, + uint32_t flags, struct nft_rule_expr *e) +{ + struct nft_expr_log *log = (struct nft_expr_log *)e->data; + + switch(type) { + case NFT_RULE_O_DEFAULT: + return snprintf(buf, len, "prefix=%s group=%u " + "snaplen=%u qthreshold=%u ", + log->prefix, log->group, + log->snaplen, log->qthreshold); + case NFT_RULE_O_XML: + return snprintf(buf, len, "%s" + "%u" + "%u" + "%u", + log->prefix, log->group, + log->snaplen, log->qthreshold); + default: + break; + } + return -1; +} + +struct expr_ops expr_ops_log = { + .name = "log", + .alloc_len = sizeof(struct nft_expr_log), + .max_attr = NFTA_LOG_MAX, + .set = nft_rule_expr_log_set, + .get = nft_rule_expr_log_get, + .parse = nft_rule_expr_log_parse, + .build = nft_rule_expr_log_build, + .snprintf = nft_rule_expr_log_snprintf, + .xml_parse = nft_rule_expr_log_xml_parse, +}; diff --git a/src/expr_ops.c b/src/expr_ops.c index dd9cd2e..1c67fe8 100644 --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -6,6 +6,7 @@ extern struct expr_ops expr_ops_bitwise; extern struct expr_ops expr_ops_cmp; extern struct expr_ops expr_ops_counter; extern struct expr_ops expr_ops_immediate; +extern struct expr_ops expr_ops_log; extern struct expr_ops expr_ops_lookup; extern struct expr_ops expr_ops_match; extern struct expr_ops expr_ops_meta; @@ -23,6 +24,7 @@ struct expr_ops *expr_ops[] = { &expr_ops_nat, &expr_ops_payload, &expr_ops_target, + &expr_ops_log, &expr_ops_lookup, NULL, }; -- cgit v1.2.3