diff options
Diffstat (limited to 'src/object.c')
| -rw-r--r-- | src/object.c | 562 |
1 files changed, 562 insertions, 0 deletions
diff --git a/src/object.c b/src/object.c new file mode 100644 index 0000000..232b97a --- /dev/null +++ b/src/object.c @@ -0,0 +1,562 @@ +/* + * (C) 2012-2016 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * 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. + */ +#include "internal.h" + +#include <time.h> +#include <endian.h> +#include <stdint.h> +#include <limits.h> +#include <stdlib.h> +#include <string.h> +#include <netinet/in.h> +#include <errno.h> + +#include <libmnl/libmnl.h> +#include <linux/netfilter/nfnetlink.h> +#include <linux/netfilter/nf_tables.h> + +#include <libnftnl/object.h> +#include "obj.h" + +static struct obj_ops *obj_ops[__NFT_OBJECT_MAX] = { + [NFT_OBJECT_COUNTER] = &obj_ops_counter, + [NFT_OBJECT_QUOTA] = &obj_ops_quota, + [NFT_OBJECT_CT_HELPER] = &obj_ops_ct_helper, + [NFT_OBJECT_LIMIT] = &obj_ops_limit, + [NFT_OBJECT_TUNNEL] = &obj_ops_tunnel, + [NFT_OBJECT_CT_TIMEOUT] = &obj_ops_ct_timeout, + [NFT_OBJECT_SECMARK] = &obj_ops_secmark, + [NFT_OBJECT_CT_EXPECT] = &obj_ops_ct_expect, + [NFT_OBJECT_SYNPROXY] = &obj_ops_synproxy, +}; + +static struct obj_ops *nftnl_obj_ops_lookup(uint32_t type) +{ + if (type > NFT_OBJECT_MAX) + return NULL; + + return obj_ops[type]; +} + +EXPORT_SYMBOL(nftnl_obj_alloc); +struct nftnl_obj *nftnl_obj_alloc(void) +{ + return calloc(1, sizeof(struct nftnl_obj)); +} + +EXPORT_SYMBOL(nftnl_obj_free); +void nftnl_obj_free(const struct nftnl_obj *obj) +{ + if (obj->flags & (1 << NFTNL_OBJ_TABLE)) + xfree(obj->table); + if (obj->flags & (1 << NFTNL_OBJ_NAME)) + xfree(obj->name); + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + xfree(obj->user.data); + + xfree(obj); +} + +EXPORT_SYMBOL(nftnl_obj_is_set); +bool nftnl_obj_is_set(const struct nftnl_obj *obj, uint16_t attr) +{ + return obj->flags & (1 << attr); +} + +static uint32_t nftnl_obj_validate[NFTNL_OBJ_MAX + 1] = { + [NFTNL_OBJ_FAMILY] = sizeof(uint32_t), + [NFTNL_OBJ_USE] = sizeof(uint32_t), + [NFTNL_OBJ_HANDLE] = sizeof(uint64_t), +}; + +EXPORT_SYMBOL(nftnl_obj_set_data); +void nftnl_obj_set_data(struct nftnl_obj *obj, uint16_t attr, + const void *data, uint32_t data_len) +{ + if (attr < NFTNL_OBJ_MAX) + nftnl_assert_validate(data, nftnl_obj_validate, attr, data_len); + + switch (attr) { + case NFTNL_OBJ_TABLE: + xfree(obj->table); + obj->table = strdup(data); + break; + case NFTNL_OBJ_NAME: + xfree(obj->name); + obj->name = strdup(data); + break; + case NFTNL_OBJ_TYPE: + obj->ops = nftnl_obj_ops_lookup(*((uint32_t *)data)); + if (!obj->ops) + return; + break; + case NFTNL_OBJ_FAMILY: + memcpy(&obj->family, data, sizeof(obj->family)); + break; + case NFTNL_OBJ_USE: + memcpy(&obj->use, data, sizeof(obj->use)); + break; + case NFTNL_OBJ_HANDLE: + memcpy(&obj->handle, data, sizeof(obj->handle)); + break; + case NFTNL_OBJ_USERDATA: + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + xfree(obj->user.data); + + obj->user.data = malloc(data_len); + if (!obj->user.data) + return; + memcpy(obj->user.data, data, data_len); + obj->user.len = data_len; + break; + default: + if (obj->ops) + obj->ops->set(obj, attr, data, data_len); + break; + } + obj->flags |= (1 << attr); +} + +void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data) __visible; +void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data) +{ + nftnl_obj_set_data(obj, attr, data, nftnl_obj_validate[attr]); +} + +EXPORT_SYMBOL(nftnl_obj_set_u8); +void nftnl_obj_set_u8(struct nftnl_obj *obj, uint16_t attr, uint8_t val) +{ + nftnl_obj_set_data(obj, attr, &val, sizeof(uint8_t)); +} + +EXPORT_SYMBOL(nftnl_obj_set_u16); +void nftnl_obj_set_u16(struct nftnl_obj *obj, uint16_t attr, uint16_t val) +{ + nftnl_obj_set_data(obj, attr, &val, sizeof(uint16_t)); +} + +EXPORT_SYMBOL(nftnl_obj_set_u32); +void nftnl_obj_set_u32(struct nftnl_obj *obj, uint16_t attr, uint32_t val) +{ + nftnl_obj_set_data(obj, attr, &val, sizeof(uint32_t)); +} + +EXPORT_SYMBOL(nftnl_obj_set_u64); +void nftnl_obj_set_u64(struct nftnl_obj *obj, uint16_t attr, uint64_t val) +{ + nftnl_obj_set_data(obj, attr, &val, sizeof(uint64_t)); +} + +EXPORT_SYMBOL(nftnl_obj_set_str); +void nftnl_obj_set_str(struct nftnl_obj *obj, uint16_t attr, const char *str) +{ + nftnl_obj_set_data(obj, attr, str, 0); +} + +EXPORT_SYMBOL(nftnl_obj_get_data); +const void *nftnl_obj_get_data(struct nftnl_obj *obj, uint16_t attr, + uint32_t *data_len) +{ + if (!(obj->flags & (1 << attr))) + return NULL; + + switch(attr) { + case NFTNL_OBJ_TABLE: + return obj->table; + case NFTNL_OBJ_NAME: + return obj->name; + case NFTNL_OBJ_TYPE: + if (!obj->ops) + return NULL; + + *data_len = sizeof(uint32_t); + return &obj->ops->type; + case NFTNL_OBJ_FAMILY: + *data_len = sizeof(uint32_t); + return &obj->family; + case NFTNL_OBJ_USE: + *data_len = sizeof(uint32_t); + return &obj->use; + case NFTNL_OBJ_HANDLE: + *data_len = sizeof(uint64_t); + return &obj->handle; + case NFTNL_OBJ_USERDATA: + *data_len = obj->user.len; + return obj->user.data; + default: + if (obj->ops) + return obj->ops->get(obj, attr, data_len); + break; + } + return NULL; +} + +EXPORT_SYMBOL(nftnl_obj_get); +const void *nftnl_obj_get(struct nftnl_obj *obj, uint16_t attr) +{ + uint32_t data_len; + return nftnl_obj_get_data(obj, attr, &data_len); +} + +EXPORT_SYMBOL(nftnl_obj_get_u8); +uint8_t nftnl_obj_get_u8(struct nftnl_obj *obj, uint16_t attr) +{ + const void *ret = nftnl_obj_get(obj, attr); + return ret == NULL ? 0 : *((uint8_t *)ret); +} + +EXPORT_SYMBOL(nftnl_obj_get_u16); +uint16_t nftnl_obj_get_u16(struct nftnl_obj *obj, uint16_t attr) +{ + const void *ret = nftnl_obj_get(obj, attr); + return ret == NULL ? 0 : *((uint16_t *)ret); +} + +EXPORT_SYMBOL(nftnl_obj_get_u32); +uint32_t nftnl_obj_get_u32(struct nftnl_obj *obj, uint16_t attr) +{ + const void *ret = nftnl_obj_get(obj, attr); + return ret == NULL ? 0 : *((uint32_t *)ret); +} + +EXPORT_SYMBOL(nftnl_obj_get_u64); +uint64_t nftnl_obj_get_u64(struct nftnl_obj *obj, uint16_t attr) +{ + const void *ret = nftnl_obj_get(obj, attr); + return ret == NULL ? 0 : *((uint64_t *)ret); +} + +EXPORT_SYMBOL(nftnl_obj_get_str); +const char *nftnl_obj_get_str(struct nftnl_obj *obj, uint16_t attr) +{ + return nftnl_obj_get(obj, attr); +} + +EXPORT_SYMBOL(nftnl_obj_nlmsg_build_payload); +void nftnl_obj_nlmsg_build_payload(struct nlmsghdr *nlh, + const struct nftnl_obj *obj) +{ + if (obj->flags & (1 << NFTNL_OBJ_TABLE)) + mnl_attr_put_strz(nlh, NFTA_OBJ_TABLE, obj->table); + if (obj->flags & (1 << NFTNL_OBJ_NAME)) + mnl_attr_put_strz(nlh, NFTA_OBJ_NAME, obj->name); + if (obj->flags & (1 << NFTNL_OBJ_TYPE)) + mnl_attr_put_u32(nlh, NFTA_OBJ_TYPE, htonl(obj->ops->type)); + if (obj->flags & (1 << NFTNL_OBJ_HANDLE)) + mnl_attr_put_u64(nlh, NFTA_OBJ_HANDLE, htobe64(obj->handle)); + if (obj->flags & (1 << NFTNL_OBJ_USERDATA)) + mnl_attr_put(nlh, NFTA_OBJ_USERDATA, obj->user.len, obj->user.data); + if (obj->ops) { + struct nlattr *nest = mnl_attr_nest_start(nlh, NFTA_OBJ_DATA); + + obj->ops->build(nlh, obj); + mnl_attr_nest_end(nlh, nest); + } +} + +static int nftnl_obj_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_OBJ_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_OBJ_TABLE: + case NFTA_OBJ_NAME: + if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) + abi_breakage(); + break; + case NFTA_OBJ_HANDLE: + if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) + abi_breakage(); + break; + case NFTA_OBJ_DATA: + if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0) + abi_breakage(); + break; + case NFTA_OBJ_USE: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + case NFTA_OBJ_USERDATA: + if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +EXPORT_SYMBOL(nftnl_obj_nlmsg_parse); +int nftnl_obj_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_obj *obj) +{ + struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh); + struct nlattr *tb[NFTA_OBJ_MAX + 1] = {}; + int err; + + if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_obj_parse_attr_cb, tb) < 0) + return -1; + + if (tb[NFTA_OBJ_TABLE]) { + obj->table = strdup(mnl_attr_get_str(tb[NFTA_OBJ_TABLE])); + obj->flags |= (1 << NFTNL_OBJ_TABLE); + } + if (tb[NFTA_OBJ_NAME]) { + obj->name = strdup(mnl_attr_get_str(tb[NFTA_OBJ_NAME])); + obj->flags |= (1 << NFTNL_OBJ_NAME); + } + if (tb[NFTA_OBJ_TYPE]) { + uint32_t type = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_TYPE])); + + obj->ops = nftnl_obj_ops_lookup(type); + if (obj->ops) + obj->flags |= (1 << NFTNL_OBJ_TYPE); + } + if (tb[NFTA_OBJ_DATA]) { + if (obj->ops) { + err = obj->ops->parse(obj, tb[NFTA_OBJ_DATA]); + if (err < 0) + return err; + } + } + if (tb[NFTA_OBJ_USE]) { + obj->use = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_USE])); + obj->flags |= (1 << NFTNL_OBJ_USE); + } + if (tb[NFTA_OBJ_HANDLE]) { + obj->handle = be64toh(mnl_attr_get_u64(tb[NFTA_OBJ_HANDLE])); + obj->flags |= (1 << NFTNL_OBJ_HANDLE); + } + if (tb[NFTA_OBJ_USERDATA]) { + nftnl_obj_set_data(obj, NFTNL_OBJ_USERDATA, + mnl_attr_get_payload(tb[NFTA_OBJ_USERDATA]), + mnl_attr_get_payload_len(tb[NFTA_OBJ_USERDATA])); + } + + obj->family = nfg->nfgen_family; + obj->flags |= (1 << NFTNL_OBJ_FAMILY); + + return 0; +} + +static int nftnl_obj_do_parse(struct nftnl_obj *obj, enum nftnl_parse_type type, + const void *data, struct nftnl_parse_err *err, + enum nftnl_parse_input input) +{ + struct nftnl_parse_err perr = {}; + int ret; + + switch (type) { + case NFTNL_PARSE_JSON: + case NFTNL_PARSE_XML: + default: + ret = -1; + errno = EOPNOTSUPP; + break; + } + + if (err != NULL) + *err = perr; + + return ret; +} + +EXPORT_SYMBOL(nftnl_obj_parse); +int nftnl_obj_parse(struct nftnl_obj *obj, enum nftnl_parse_type type, + const char *data, struct nftnl_parse_err *err) +{ + return nftnl_obj_do_parse(obj, type, data, err, NFTNL_PARSE_BUFFER); +} + +EXPORT_SYMBOL(nftnl_obj_parse_file); +int nftnl_obj_parse_file(struct nftnl_obj *obj, enum nftnl_parse_type type, + FILE *fp, struct nftnl_parse_err *err) +{ + return nftnl_obj_do_parse(obj, type, fp, err, NFTNL_PARSE_FILE); +} + +static int nftnl_obj_snprintf_dflt(char *buf, size_t remain, + const struct nftnl_obj *obj, + uint32_t type, uint32_t flags) +{ + const char *name = obj->ops ? obj->ops->name : "(unknown)"; + int ret, offset = 0; + + ret = snprintf(buf, remain, "table %s name %s use %u [ %s ", + obj->table, obj->name, obj->use, name); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + + if (obj->ops) { + ret = obj->ops->output(buf + offset, remain, flags, obj); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + ret = snprintf(buf + offset, remain, "]"); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + + return offset; +} + +static int nftnl_obj_cmd_snprintf(char *buf, size_t remain, + const struct nftnl_obj *obj, uint32_t cmd, + uint32_t type, uint32_t flags) +{ + int ret, offset = 0; + + if (type != NFTNL_OUTPUT_DEFAULT) + return -1; + + ret = nftnl_obj_snprintf_dflt(buf + offset, remain, obj, type, flags); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + return offset; +} + +EXPORT_SYMBOL(nftnl_obj_snprintf); +int nftnl_obj_snprintf(char *buf, size_t size, const struct nftnl_obj *obj, + uint32_t type, uint32_t flags) +{ + if (size) + buf[0] = '\0'; + + return nftnl_obj_cmd_snprintf(buf, size, obj, nftnl_flag2cmd(flags), + type, flags); +} + +static int nftnl_obj_do_snprintf(char *buf, size_t size, const void *obj, + uint32_t cmd, uint32_t type, uint32_t flags) +{ + return nftnl_obj_snprintf(buf, size, obj, type, flags); +} + +EXPORT_SYMBOL(nftnl_obj_fprintf); +int nftnl_obj_fprintf(FILE *fp, const struct nftnl_obj *obj, uint32_t type, + uint32_t flags) +{ + return nftnl_fprintf(fp, obj, NFTNL_CMD_UNSPEC, type, flags, + nftnl_obj_do_snprintf); +} + +struct nftnl_obj_list { + struct list_head list; +}; + +EXPORT_SYMBOL(nftnl_obj_list_alloc); +struct nftnl_obj_list *nftnl_obj_list_alloc(void) +{ + struct nftnl_obj_list *list; + + list = calloc(1, sizeof(struct nftnl_obj_list)); + if (list == NULL) + return NULL; + + INIT_LIST_HEAD(&list->list); + + return list; +} + +EXPORT_SYMBOL(nftnl_obj_list_free); +void nftnl_obj_list_free(struct nftnl_obj_list *list) +{ + struct nftnl_obj *r, *tmp; + + list_for_each_entry_safe(r, tmp, &list->list, head) { + list_del(&r->head); + nftnl_obj_free(r); + } + xfree(list); +} + +EXPORT_SYMBOL(nftnl_obj_list_is_empty); +int nftnl_obj_list_is_empty(struct nftnl_obj_list *list) +{ + return list_empty(&list->list); +} + +EXPORT_SYMBOL(nftnl_obj_list_add); +void nftnl_obj_list_add(struct nftnl_obj *r, struct nftnl_obj_list *list) +{ + list_add(&r->head, &list->list); +} + +EXPORT_SYMBOL(nftnl_obj_list_add_tail); +void nftnl_obj_list_add_tail(struct nftnl_obj *r, + struct nftnl_obj_list *list) +{ + list_add_tail(&r->head, &list->list); +} + +EXPORT_SYMBOL(nftnl_obj_list_del); +void nftnl_obj_list_del(struct nftnl_obj *t) +{ + list_del(&t->head); +} + +EXPORT_SYMBOL(nftnl_obj_list_foreach); +int nftnl_obj_list_foreach(struct nftnl_obj_list *table_list, + int (*cb)(struct nftnl_obj *t, void *data), + void *data) +{ + struct nftnl_obj *cur, *tmp; + int ret; + + list_for_each_entry_safe(cur, tmp, &table_list->list, head) { + ret = cb(cur, data); + if (ret < 0) + return ret; + } + return 0; +} + +struct nftnl_obj_list_iter { + struct nftnl_obj_list *list; + struct nftnl_obj *cur; +}; + +EXPORT_SYMBOL(nftnl_obj_list_iter_create); +struct nftnl_obj_list_iter * +nftnl_obj_list_iter_create(struct nftnl_obj_list *l) +{ + struct nftnl_obj_list_iter *iter; + + iter = calloc(1, sizeof(struct nftnl_obj_list_iter)); + if (iter == NULL) + return NULL; + + iter->list = l; + if (nftnl_obj_list_is_empty(l)) + iter->cur = NULL; + else + iter->cur = list_entry(l->list.next, struct nftnl_obj, head); + + return iter; +} + +EXPORT_SYMBOL(nftnl_obj_list_iter_next); +struct nftnl_obj *nftnl_obj_list_iter_next(struct nftnl_obj_list_iter *iter) +{ + struct nftnl_obj *r = iter->cur; + + if (r == NULL) + return NULL; + + /* get next table, if any */ + iter->cur = list_entry(iter->cur->head.next, struct nftnl_obj, head); + if (&iter->cur->head == iter->list->list.next) + return NULL; + + return r; +} + +EXPORT_SYMBOL(nftnl_obj_list_iter_destroy); +void nftnl_obj_list_iter_destroy(struct nftnl_obj_list_iter *iter) +{ + xfree(iter); +} |