diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/libnetfilter_acct.c | 181 |
1 files changed, 157 insertions, 24 deletions
diff --git a/src/libnetfilter_acct.c b/src/libnetfilter_acct.c index 86d7b96..9fe7d51 100644 --- a/src/libnetfilter_acct.c +++ b/src/libnetfilter_acct.c @@ -20,6 +20,41 @@ #include <libnetfilter_acct/libnetfilter_acct.h> +/** + * \mainpage + * + * libnetfilter_acct is the userspace library that provides a programming + * interface (API) to the extended accounting infrastructure. Basically, you + * can find here a set of helper functions that you can use together with + * libmnl. + * + * libnetfilter_acct homepage is: + * http://netfilter.org/projects/libnetfilter_acct/ + * + * \section Dependencies + * libnetfilter_acct requires libmnl >= 1.0.0 and the Linux kernel that + * includes the nfnetlink_acct subsystem (i.e. 3.3.x or any later). + * + * \section Main Features + * - listing/retrieving existing accounting objects. + * - atomically retrieving and reset accounting objects. + * - inserting/modifying/deleting accounting objects. + * + * \section Git Tree + * The current development version of libnetfilter_acct can be accessed at + * https://git.netfilter.org/cgi-bin/gitweb.cgi?p=libnetfilter_acct.git + * + * \section using Using libnetfilter_acct + * To write your own program using libnetfilter_acct, you should start by + * reading the documentation for libmnl to understand basic operation with + * Netlink sockets. Moreover, you may want to check the examples available + * under examples/ in the libnetfilter_acct source code. You can compile + * these examples by invoking `make check'. + * + * \section Authors + * libnetfilter_acct has been written by Pablo Neira Ayuso. + */ + struct nfacct { char name[NFACCT_NAME_MAX]; uint64_t pkts; @@ -27,18 +62,39 @@ struct nfacct { uint32_t bitset; }; +/** + * \defgroup nfacct Accounting object handling + * @{ + */ + +/** + * nfacct_alloc - allocate a new accounting object + * + * In case of success, this function returns a valid pointer, otherwise NULL + * s returned and errno is appropriately set. + */ struct nfacct *nfacct_alloc(void) { return calloc(1, sizeof(struct nfacct)); } EXPORT_SYMBOL(nfacct_alloc); +/** + * nfacct_free - release one accounting object + * \param nfacct pointer to the accounting object + */ void nfacct_free(struct nfacct *nfacct) { free(nfacct); } EXPORT_SYMBOL(nfacct_free); +/** + * nfacct_attr_set - set one attribute of the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * \param data pointer to data that will be used to set this attribute + */ void nfacct_attr_set(struct nfacct *nfacct, enum nfacct_attr_type type, const void *data) @@ -61,6 +117,12 @@ nfacct_attr_set(struct nfacct *nfacct, enum nfacct_attr_type type, } EXPORT_SYMBOL(nfacct_attr_set); +/** + * nfacct_attr_set_str - set one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * \param name string that will be used to set this attribute + */ void nfacct_attr_set_str(struct nfacct *nfacct, enum nfacct_attr_type type, const char *name) @@ -69,6 +131,12 @@ nfacct_attr_set_str(struct nfacct *nfacct, enum nfacct_attr_type type, } EXPORT_SYMBOL(nfacct_attr_set_str); +/** + * nfacct_attr_set_u64 - set one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * \param value unsigned 64-bits integer + */ void nfacct_attr_set_u64(struct nfacct *nfacct, enum nfacct_attr_type type, uint64_t value) @@ -77,6 +145,11 @@ nfacct_attr_set_u64(struct nfacct *nfacct, enum nfacct_attr_type type, } EXPORT_SYMBOL(nfacct_attr_set_u64); +/** + * nfacct_attr_unset - unset one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + */ void nfacct_attr_unset(struct nfacct *nfacct, enum nfacct_attr_type type) { @@ -94,6 +167,14 @@ nfacct_attr_unset(struct nfacct *nfacct, enum nfacct_attr_type type) } EXPORT_SYMBOL(nfacct_attr_unset); +/** + * nfacct_attr_get - get one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * + * This function returns a valid pointer to the attribute data. If a + * unsupported attribute is used, this returns NULL. + */ const void *nfacct_attr_get(struct nfacct *nfacct, enum nfacct_attr_type type) { const void *ret = NULL; @@ -113,6 +194,14 @@ const void *nfacct_attr_get(struct nfacct *nfacct, enum nfacct_attr_type type) } EXPORT_SYMBOL(nfacct_attr_get); +/** + * nfacct_attr_get_str - get one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * + * This function returns a valid pointer to the beginning of the string. + * If the attribute is unsupported, this returns NULL. + */ const char * nfacct_attr_get_str(struct nfacct *nfacct, enum nfacct_attr_type type) { @@ -120,6 +209,14 @@ nfacct_attr_get_str(struct nfacct *nfacct, enum nfacct_attr_type type) } EXPORT_SYMBOL(nfacct_attr_get_str); +/** + * nfacct_attr_get_u64 - get one attribute the accounting object + * \param nfacct pointer to the accounting object + * \param type attribute type you want to set + * + * This function returns a unsigned 64-bits integer. If the attribute is + * unsupported, this returns NULL. + */ uint64_t nfacct_attr_get_u64(struct nfacct *nfacct, enum nfacct_attr_type type) { return *((uint64_t *)nfacct_attr_get(nfacct, type)); @@ -127,11 +224,51 @@ uint64_t nfacct_attr_get_u64(struct nfacct *nfacct, enum nfacct_attr_type type) EXPORT_SYMBOL(nfacct_attr_get_u64); /** + * nfacct_snprintf - print accounting object into one buffer + * \param buf: pointer to buffer that is used to print the object + * \param size: size of the buffer (or remaining room in it). + * \param nfacct: pointer to a valid accounting object. + * \param flags: output flags (NFACCT_SNPRINTF_F_FULL). + * + * This function returns -1 in case that some mandatory attributes are + * missing. On sucess, it returns 0. + */ +int nfacct_snprintf(char *buf, size_t size, struct nfacct *nfacct, + unsigned int flags) +{ + int ret; + + if (flags & NFACCT_SNPRINTF_F_FULL) { + ret = snprintf(buf, size, + "%s = { pkts = %.12llu,\tbytes = %.12llu };", + nfacct_attr_get_str(nfacct, NFACCT_ATTR_NAME), + (unsigned long long) + nfacct_attr_get_u64(nfacct, NFACCT_ATTR_BYTES), + (unsigned long long) + nfacct_attr_get_u64(nfacct, NFACCT_ATTR_PKTS)); + } else { + ret = snprintf(buf, size, "%s\n", + nfacct_attr_get_str(nfacct, NFACCT_ATTR_NAME)); + } + return ret; +} +EXPORT_SYMBOL(nfacct_snprintf); + +/** + * @} + */ + +/** + * \defgroup nlmsg Netlink message helper functions + * @{ + */ + +/** * nfacct_nlmsg_build_hdr - build netlink message header for nfacct subsystem - * @buf: buffer where this function outputs the netlink message. - * @cmd: nfacct nfnetlink command. - * @flags: netlink flags. - * @seq: sequence number for this message. + * \param buf: buffer where this function outputs the netlink message. + * \param cmd: nfacct nfnetlink command. + * \param flags: netlink flags. + * \param seq: sequence number for this message. * * Possible commands: * - NFNL_MSG_ACCT_NEW: new accounting object. @@ -174,6 +311,11 @@ nfacct_nlmsg_build_hdr(char *buf, uint8_t cmd, uint16_t flags, uint32_t seq) } EXPORT_SYMBOL(nfacct_nlmsg_build_hdr); +/** + * nfacct_nlmsg_build_payload - build payload from accounting object + * \param nlh: netlink message that you want to use to add the payload. + * \param nfacct: pointer to a accounting object + */ void nfacct_nlmsg_build_payload(struct nlmsghdr *nlh, struct nfacct *nfacct) { if (nfacct->name) @@ -219,6 +361,14 @@ static int nfacct_nlmsg_parse_attr_cb(const struct nlattr *attr, void *data) return MNL_CB_OK; } +/** + * nfacct_nlmsg_parse_payload - set accounting object attributes from message + * \param nlh: netlink message that you want to use to add the payload. + * \param nfacct: pointer to a accounting object + * + * This function returns -1 in case that some mandatory attributes are + * missing. On sucess, it returns 0. + */ int nfacct_nlmsg_parse_payload(const struct nlmsghdr *nlh, struct nfacct *nfacct) { @@ -240,23 +390,6 @@ nfacct_nlmsg_parse_payload(const struct nlmsghdr *nlh, struct nfacct *nfacct) } EXPORT_SYMBOL(nfacct_nlmsg_parse_payload); -int nfacct_snprintf(char *buf, size_t size, struct nfacct *nfacct, - unsigned int flags) -{ - int ret; - - if (flags & NFACCT_SNPRINTF_F_FULL) { - ret = snprintf(buf, size, - "%s = { pkts = %.12llu,\tbytes = %.12llu };", - nfacct_attr_get_str(nfacct, NFACCT_ATTR_NAME), - (unsigned long long) - nfacct_attr_get_u64(nfacct, NFACCT_ATTR_BYTES), - (unsigned long long) - nfacct_attr_get_u64(nfacct, NFACCT_ATTR_PKTS)); - } else { - ret = snprintf(buf, size, "%s\n", - nfacct_attr_get_str(nfacct, NFACCT_ATTR_NAME)); - } - return ret; -} -EXPORT_SYMBOL(nfacct_snprintf); +/** + * @} + */ |