diff options
| -rw-r--r-- | include/libmnl/libmnl.h | 10 | ||||
| -rw-r--r-- | src/attr.c | 174 | ||||
| -rw-r--r-- | src/libmnl.map | 8 |
3 files changed, 192 insertions, 0 deletions
diff --git a/include/libmnl/libmnl.h b/include/libmnl/libmnl.h index 5b8d78c..1237b6d 100644 --- a/include/libmnl/libmnl.h +++ b/include/libmnl/libmnl.h @@ -93,8 +93,18 @@ extern void mnl_attr_put_u64(struct nlmsghdr *nlh, uint16_t type, uint64_t data) extern void mnl_attr_put_str(struct nlmsghdr *nlh, uint16_t type, const char *data); extern void mnl_attr_put_strz(struct nlmsghdr *nlh, uint16_t type, const char *data); +/* TLV attribute putters with buffer boundary checkings */ +extern bool mnl_attr_put_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, size_t len, const void *data); +extern bool mnl_attr_put_u8_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint8_t data); +extern bool mnl_attr_put_u16_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint16_t data); +extern bool mnl_attr_put_u32_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint32_t data); +extern bool mnl_attr_put_u64_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint64_t data); +extern bool mnl_attr_put_str_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data); +extern bool mnl_attr_put_strz_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data); + /* TLV attribute nesting */ extern struct nlattr *mnl_attr_nest_start(struct nlmsghdr *nlh, uint16_t type); +extern struct nlattr *mnl_attr_nest_start_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type); extern void mnl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *start); extern void mnl_attr_nest_cancel(struct nlmsghdr *nlh, struct nlattr *start); @@ -491,6 +491,180 @@ mnl_attr_nest_start(struct nlmsghdr *nlh, uint16_t type) } /** + * mnl_attr_put_check - add an attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type that you want to add + * \param len netlink attribute payload length + * \param data pointer to the data that will be stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + */ +EXPORT_SYMBOL bool +mnl_attr_put_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, size_t len, const void *data) +{ + if (nlh->nlmsg_len + MNL_ATTR_HDRLEN + MNL_ALIGN(len) > buflen) + return false; + mnl_attr_put(nlh, type, len, data); + return true; +} + +/** + * mnl_attr_put_u8_check - add 8-bit unsigned int attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param len netlink attribute payload size + * \param data 8-bit unsigned integer data that is stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + */ +EXPORT_SYMBOL bool +mnl_attr_put_u8_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, uint8_t data) +{ + return mnl_attr_put_check(nlh, buflen, type, sizeof(uint8_t), &data); +} + +/** + * mnl_attr_put_u16_check - add 16-bit unsigned int attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param data 16-bit unsigned integer data that is stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + * This function updates the length field of the Netlink message (nlmsg_len) + * by adding the size (header + payload) of the new attribute. + */ +EXPORT_SYMBOL bool +mnl_attr_put_u16_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, uint16_t data) +{ + return mnl_attr_put_check(nlh, buflen, type, sizeof(uint16_t), &data); +} + +/** + * mnl_attr_put_u32_check - add 32-bit unsigned int attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param data 32-bit unsigned integer data that is stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + * This function updates the length field of the Netlink message (nlmsg_len) + * by adding the size (header + payload) of the new attribute. + */ +EXPORT_SYMBOL bool +mnl_attr_put_u32_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, uint32_t data) +{ + return mnl_attr_put_check(nlh, buflen, type, sizeof(uint32_t), &data); +} + +/** + * mnl_attr_put_u64_check - add 64-bit unsigned int attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param data 64-bit unsigned integer data that is stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + * This function updates the length field of the Netlink message (nlmsg_len) + * by adding the size (header + payload) of the new attribute. + */ +EXPORT_SYMBOL bool +mnl_attr_put_u64_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, uint64_t data) +{ + return mnl_attr_put_check(nlh, buflen, type, sizeof(uint64_t), &data); +} + +/** + * mnl_attr_put_str_check - add string attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param data pointer to string data that is stored by the new attribute + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + * This function updates the length field of the Netlink message (nlmsg_len) + * by adding the size (header + payload) of the new attribute. + */ +EXPORT_SYMBOL bool +mnl_attr_put_str_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, const char *data) +{ + return mnl_attr_put_check(nlh, buflen, type, strlen(data), data); +} + +/** + * mnl_attr_put_strz_check - add string attribute to netlink message + * \param nlh pointer to the netlink message + * \param buflen size of buffer which stores the message + * \param type netlink attribute type + * \param data pointer to string data that is stored by the new attribute + * + * This function is similar to mnl_attr_put_str, but it includes the + * NUL/zero ('\0') terminator at the end of the string. + * + * This function first checks that the data can be added to the message + * (fits into the buffer) and then updates the length field of the Netlink + * message (nlmsg_len) by adding the size (header + payload) of the new + * attribute. The function returns true if the attribute could be added + * to the message, otherwise false is returned. + */ +EXPORT_SYMBOL bool +mnl_attr_put_strz_check(struct nlmsghdr *nlh, size_t buflen, + uint16_t type, const char *data) +{ + return mnl_attr_put_check(nlh, buflen, type, strlen(data)+1, data); +} + +/** + * mnl_attr_nest_start_check - start an attribute nest + * \param buflen size of buffer which stores the message + * \param nlh pointer to the netlink message + * \param type netlink attribute type + * + * This function adds the attribute header that identifies the beginning of + * an attribute nest. If the nested attribute cannot be added then NULL, + * otherwise valid pointer to the beginning of the nest is returned. + */ +EXPORT_SYMBOL struct nlattr * +mnl_attr_nest_start_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type) +{ + if (nlh->nlmsg_len + MNL_ATTR_HDRLEN > buflen) + return NULL; + return mnl_attr_nest_start(nlh, type); +} + +/** * mnl_attr_nest_end - end an attribute nest * \param nlh pointer to the netlink message * \param start pointer to the attribute nest returned by mnl_attr_nest_start() diff --git a/src/libmnl.map b/src/libmnl.map index 4bbd06e..01bb924 100644 --- a/src/libmnl.map +++ b/src/libmnl.map @@ -11,6 +11,7 @@ global: mnl_attr_get_u8; mnl_attr_nest_end; mnl_attr_nest_start; + mnl_attr_nest_start_check; mnl_attr_nest_cancel; mnl_attr_next; mnl_attr_ok; @@ -23,6 +24,13 @@ global: mnl_attr_put_u32; mnl_attr_put_u64; mnl_attr_put_u8; + mnl_attr_put_check; + mnl_attr_put_str_check; + mnl_attr_put_strz_check; + mnl_attr_put_u16_check; + mnl_attr_put_u32_check; + mnl_attr_put_u64_check; + mnl_attr_put_u8_check; mnl_attr_type_valid; mnl_attr_validate; mnl_attr_validate2; |