| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef GENL_MAGIC_FUNC_H |
| #define GENL_MAGIC_FUNC_H |
| |
| #include <linux/build_bug.h> |
| #include <linux/genl_magic_struct.h> |
| |
| /* |
| * Magic: declare tla policy {{{1 |
| * Magic: declare nested policies |
| * {{{2 |
| */ |
| #undef GENL_mc_group |
| #define GENL_mc_group(group) |
| |
| #undef GENL_notification |
| #define GENL_notification(op_name, op_num, mcast_group, tla_list) |
| |
| #undef GENL_op |
| #define GENL_op(op_name, op_num, handler, tla_list) |
| |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ |
| [tag_name] = { .type = NLA_NESTED }, |
| |
| static struct nla_policy CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy)[] = { |
| #include GENL_MAGIC_INCLUDE_FILE |
| }; |
| |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ |
| static struct nla_policy s_name ## _nl_policy[] __read_mostly = \ |
| { s_fields }; |
| |
| #undef __field |
| #define __field(attr_nr, attr_flag, name, nla_type, _type, __get, \ |
| __put, __is_signed) \ |
| [attr_nr] = { .type = nla_type }, |
| |
| #undef __array |
| #define __array(attr_nr, attr_flag, name, nla_type, _type, maxlen, \ |
| __get, __put, __is_signed) \ |
| [attr_nr] = { .type = nla_type, \ |
| .len = maxlen - (nla_type == NLA_NUL_STRING) }, |
| |
| #include GENL_MAGIC_INCLUDE_FILE |
| |
| #ifndef __KERNEL__ |
| #ifndef pr_info |
| #define pr_info(args...) fprintf(stderr, args); |
| #endif |
| #endif |
| |
| #ifdef GENL_MAGIC_DEBUG |
| static void dprint_field(const char *dir, int nla_type, |
| const char *name, void *valp) |
| { |
| __u64 val = valp ? *(__u32 *)valp : 1; |
| switch (nla_type) { |
| case NLA_U8: val = (__u8)val; |
| case NLA_U16: val = (__u16)val; |
| case NLA_U32: val = (__u32)val; |
| pr_info("%s attr %s: %d 0x%08x\n", dir, |
| name, (int)val, (unsigned)val); |
| break; |
| case NLA_U64: |
| val = *(__u64*)valp; |
| pr_info("%s attr %s: %lld 0x%08llx\n", dir, |
| name, (long long)val, (unsigned long long)val); |
| break; |
| case NLA_FLAG: |
| if (val) |
| pr_info("%s attr %s: set\n", dir, name); |
| break; |
| } |
| } |
| |
| static void dprint_array(const char *dir, int nla_type, |
| const char *name, const char *val, unsigned len) |
| { |
| switch (nla_type) { |
| case NLA_NUL_STRING: |
| if (len && val[len-1] == '\0') |
| len--; |
| pr_info("%s attr %s: [len:%u] '%s'\n", dir, name, len, val); |
| break; |
| default: |
| /* we can always show 4 byte, |
| * thats what nlattr are aligned to. */ |
| pr_info("%s attr %s: [len:%u] %02x%02x%02x%02x ...\n", |
| dir, name, len, val[0], val[1], val[2], val[3]); |
| } |
| } |
| |
| #define DPRINT_TLA(a, op, b) pr_info("%s %s %s\n", a, op, b); |
| |
| /* Name is a member field name of the struct s. |
| * If s is NULL (only parsing, no copy requested in *_from_attrs()), |
| * nla is supposed to point to the attribute containing the information |
| * corresponding to that struct member. */ |
| #define DPRINT_FIELD(dir, nla_type, name, s, nla) \ |
| do { \ |
| if (s) \ |
| dprint_field(dir, nla_type, #name, &s->name); \ |
| else if (nla) \ |
| dprint_field(dir, nla_type, #name, \ |
| (nla_type == NLA_FLAG) ? NULL \ |
| : nla_data(nla)); \ |
| } while (0) |
| |
| #define DPRINT_ARRAY(dir, nla_type, name, s, nla) \ |
| do { \ |
| if (s) \ |
| dprint_array(dir, nla_type, #name, \ |
| s->name, s->name ## _len); \ |
| else if (nla) \ |
| dprint_array(dir, nla_type, #name, \ |
| nla_data(nla), nla_len(nla)); \ |
| } while (0) |
| #else |
| #define DPRINT_TLA(a, op, b) do {} while (0) |
| #define DPRINT_FIELD(dir, nla_type, name, s, nla) do {} while (0) |
| #define DPRINT_ARRAY(dir, nla_type, name, s, nla) do {} while (0) |
| #endif |
| |
| /* |
| * Magic: provide conversion functions {{{1 |
| * populate struct from attribute table: |
| * {{{2 |
| */ |
| |
| /* processing of generic netlink messages is serialized. |
| * use one static buffer for parsing of nested attributes */ |
| static struct nlattr *nested_attr_tb[128]; |
| |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ |
| /* *_from_attrs functions are static, but potentially unused */ \ |
| static int __ ## s_name ## _from_attrs(struct s_name *s, \ |
| struct genl_info *info, bool exclude_invariants) \ |
| { \ |
| const int maxtype = ARRAY_SIZE(s_name ## _nl_policy)-1; \ |
| struct nlattr *tla = info->attrs[tag_number]; \ |
| struct nlattr **ntb = nested_attr_tb; \ |
| struct nlattr *nla; \ |
| int err; \ |
| BUILD_BUG_ON(ARRAY_SIZE(s_name ## _nl_policy) > ARRAY_SIZE(nested_attr_tb)); \ |
| if (!tla) \ |
| return -ENOMSG; \ |
| DPRINT_TLA(#s_name, "<=-", #tag_name); \ |
| err = drbd_nla_parse_nested(ntb, maxtype, tla, s_name ## _nl_policy); \ |
| if (err) \ |
| return err; \ |
| \ |
| s_fields \ |
| return 0; \ |
| } __attribute__((unused)) \ |
| static int s_name ## _from_attrs(struct s_name *s, \ |
| struct genl_info *info) \ |
| { \ |
| return __ ## s_name ## _from_attrs(s, info, false); \ |
| } __attribute__((unused)) \ |
| static int s_name ## _from_attrs_for_change(struct s_name *s, \ |
| struct genl_info *info) \ |
| { \ |
| return __ ## s_name ## _from_attrs(s, info, true); \ |
| } __attribute__((unused)) \ |
| |
| #define __assign(attr_nr, attr_flag, name, nla_type, type, assignment...) \ |
| nla = ntb[attr_nr]; \ |
| if (nla) { \ |
| if (exclude_invariants && !!((attr_flag) & DRBD_F_INVARIANT)) { \ |
| pr_info("<< must not change invariant attr: %s\n", #name); \ |
| return -EEXIST; \ |
| } \ |
| assignment; \ |
| } else if (exclude_invariants && !!((attr_flag) & DRBD_F_INVARIANT)) { \ |
| /* attribute missing from payload, */ \ |
| /* which was expected */ \ |
| } else if ((attr_flag) & DRBD_F_REQUIRED) { \ |
| pr_info("<< missing attr: %s\n", #name); \ |
| return -ENOMSG; \ |
| } |
| |
| #undef __field |
| #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \ |
| __is_signed) \ |
| __assign(attr_nr, attr_flag, name, nla_type, type, \ |
| if (s) \ |
| s->name = __get(nla); \ |
| DPRINT_FIELD("<<", nla_type, name, s, nla)) |
| |
| /* validate_nla() already checked nla_len <= maxlen appropriately. */ |
| #undef __array |
| #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \ |
| __get, __put, __is_signed) \ |
| __assign(attr_nr, attr_flag, name, nla_type, type, \ |
| if (s) \ |
| s->name ## _len = \ |
| __get(s->name, nla, maxlen); \ |
| DPRINT_ARRAY("<<", nla_type, name, s, nla)) |
| |
| #include GENL_MAGIC_INCLUDE_FILE |
| |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) |
| |
| /* |
| * Magic: define op number to op name mapping {{{1 |
| * {{{2 |
| */ |
| const char *CONCAT_(GENL_MAGIC_FAMILY, _genl_cmd_to_str)(__u8 cmd) |
| { |
| switch (cmd) { |
| #undef GENL_op |
| #define GENL_op(op_name, op_num, handler, tla_list) \ |
| case op_num: return #op_name; |
| #include GENL_MAGIC_INCLUDE_FILE |
| default: |
| return "unknown"; |
| } |
| } |
| |
| #ifdef __KERNEL__ |
| #include <linux/stringify.h> |
| /* |
| * Magic: define genl_ops {{{1 |
| * {{{2 |
| */ |
| |
| #undef GENL_op |
| #define GENL_op(op_name, op_num, handler, tla_list) \ |
| { \ |
| handler \ |
| .cmd = op_name, \ |
| }, |
| |
| #define ZZZ_genl_ops CONCAT_(GENL_MAGIC_FAMILY, _genl_ops) |
| static struct genl_ops ZZZ_genl_ops[] __read_mostly = { |
| #include GENL_MAGIC_INCLUDE_FILE |
| }; |
| |
| #undef GENL_op |
| #define GENL_op(op_name, op_num, handler, tla_list) |
| |
| /* |
| * Define the genl_family, multicast groups, {{{1 |
| * and provide register/unregister functions. |
| * {{{2 |
| */ |
| #define ZZZ_genl_family CONCAT_(GENL_MAGIC_FAMILY, _genl_family) |
| static struct genl_family ZZZ_genl_family; |
| /* |
| * Magic: define multicast groups |
| * Magic: define multicast group registration helper |
| */ |
| #define ZZZ_genl_mcgrps CONCAT_(GENL_MAGIC_FAMILY, _genl_mcgrps) |
| static const struct genl_multicast_group ZZZ_genl_mcgrps[] = { |
| #undef GENL_mc_group |
| #define GENL_mc_group(group) { .name = #group, }, |
| #include GENL_MAGIC_INCLUDE_FILE |
| }; |
| |
| enum CONCAT_(GENL_MAGIC_FAMILY, group_ids) { |
| #undef GENL_mc_group |
| #define GENL_mc_group(group) CONCAT_(GENL_MAGIC_FAMILY, _group_ ## group), |
| #include GENL_MAGIC_INCLUDE_FILE |
| }; |
| |
| #undef GENL_mc_group |
| #define GENL_mc_group(group) \ |
| static int CONCAT_(GENL_MAGIC_FAMILY, _genl_multicast_ ## group)( \ |
| struct sk_buff *skb, gfp_t flags) \ |
| { \ |
| unsigned int group_id = \ |
| CONCAT_(GENL_MAGIC_FAMILY, _group_ ## group); \ |
| return genlmsg_multicast(&ZZZ_genl_family, skb, 0, \ |
| group_id, flags); \ |
| } |
| |
| #include GENL_MAGIC_INCLUDE_FILE |
| |
| #undef GENL_mc_group |
| #define GENL_mc_group(group) |
| |
| static struct genl_family ZZZ_genl_family __ro_after_init = { |
| .name = __stringify(GENL_MAGIC_FAMILY), |
| .version = GENL_MAGIC_VERSION, |
| #ifdef GENL_MAGIC_FAMILY_HDRSZ |
| .hdrsize = NLA_ALIGN(GENL_MAGIC_FAMILY_HDRSZ), |
| #endif |
| .maxattr = ARRAY_SIZE(CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy))-1, |
| .policy = CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy), |
| .ops = ZZZ_genl_ops, |
| .n_ops = ARRAY_SIZE(ZZZ_genl_ops), |
| .mcgrps = ZZZ_genl_mcgrps, |
| .n_mcgrps = ARRAY_SIZE(ZZZ_genl_mcgrps), |
| .module = THIS_MODULE, |
| }; |
| |
| int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void) |
| { |
| return genl_register_family(&ZZZ_genl_family); |
| } |
| |
| void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void) |
| { |
| genl_unregister_family(&ZZZ_genl_family); |
| } |
| |
| /* |
| * Magic: provide conversion functions {{{1 |
| * populate skb from struct. |
| * {{{2 |
| */ |
| |
| #undef GENL_op |
| #define GENL_op(op_name, op_num, handler, tla_list) |
| |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ |
| static int s_name ## _to_skb(struct sk_buff *skb, struct s_name *s, \ |
| const bool exclude_sensitive) \ |
| { \ |
| struct nlattr *tla = nla_nest_start(skb, tag_number); \ |
| if (!tla) \ |
| goto nla_put_failure; \ |
| DPRINT_TLA(#s_name, "-=>", #tag_name); \ |
| s_fields \ |
| nla_nest_end(skb, tla); \ |
| return 0; \ |
| \ |
| nla_put_failure: \ |
| if (tla) \ |
| nla_nest_cancel(skb, tla); \ |
| return -EMSGSIZE; \ |
| } \ |
| static inline int s_name ## _to_priv_skb(struct sk_buff *skb, \ |
| struct s_name *s) \ |
| { \ |
| return s_name ## _to_skb(skb, s, 0); \ |
| } \ |
| static inline int s_name ## _to_unpriv_skb(struct sk_buff *skb, \ |
| struct s_name *s) \ |
| { \ |
| return s_name ## _to_skb(skb, s, 1); \ |
| } |
| |
| |
| #undef __field |
| #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \ |
| __is_signed) \ |
| if (!exclude_sensitive || !((attr_flag) & DRBD_F_SENSITIVE)) { \ |
| DPRINT_FIELD(">>", nla_type, name, s, NULL); \ |
| if (__put(skb, attr_nr, s->name)) \ |
| goto nla_put_failure; \ |
| } |
| |
| #undef __array |
| #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \ |
| __get, __put, __is_signed) \ |
| if (!exclude_sensitive || !((attr_flag) & DRBD_F_SENSITIVE)) { \ |
| DPRINT_ARRAY(">>",nla_type, name, s, NULL); \ |
| if (__put(skb, attr_nr, min_t(int, maxlen, \ |
| s->name ## _len + (nla_type == NLA_NUL_STRING)),\ |
| s->name)) \ |
| goto nla_put_failure; \ |
| } |
| |
| #include GENL_MAGIC_INCLUDE_FILE |
| |
| |
| /* Functions for initializing structs to default values. */ |
| |
| #undef __field |
| #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put, \ |
| __is_signed) |
| #undef __array |
| #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, \ |
| __get, __put, __is_signed) |
| #undef __u32_field_def |
| #define __u32_field_def(attr_nr, attr_flag, name, default) \ |
| x->name = default; |
| #undef __s32_field_def |
| #define __s32_field_def(attr_nr, attr_flag, name, default) \ |
| x->name = default; |
| #undef __flg_field_def |
| #define __flg_field_def(attr_nr, attr_flag, name, default) \ |
| x->name = default; |
| #undef __str_field_def |
| #define __str_field_def(attr_nr, attr_flag, name, maxlen) \ |
| memset(x->name, 0, sizeof(x->name)); \ |
| x->name ## _len = 0; |
| #undef GENL_struct |
| #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ |
| static void set_ ## s_name ## _defaults(struct s_name *x) __attribute__((unused)); \ |
| static void set_ ## s_name ## _defaults(struct s_name *x) { \ |
| s_fields \ |
| } |
| |
| #include GENL_MAGIC_INCLUDE_FILE |
| |
| #endif /* __KERNEL__ */ |
| |
| /* }}}1 */ |
| #endif /* GENL_MAGIC_FUNC_H */ |