[PATCH 2/3] libnetlink: add nl_print_policy() helper
From: Johannes Berg <johannes@sipsolutions.net>
Date: 2020-08-24 17:51:27
Also in:
linux-wireless
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
This prints out the data from the given nested attribute to the given FILE pointer, interpreting the firmware that the kernel has for showing netlink policies. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> --- include/libnetlink.h | 2 ++ lib/libnetlink.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+)
diff --git a/include/libnetlink.h b/include/libnetlink.h
index 0d4a9f29afbd..b9073a6a13ad 100644
--- a/include/libnetlink.h
+++ b/include/libnetlink.h@@ -289,4 +289,6 @@ int rtnl_from_file(FILE *, rtnl_listen_filter_t handler, RTA_OK(attr, RTA_PAYLOAD(nest) - ((char *)(attr) - (char *)RTA_DATA((nest)))); \ (attr) = RTA_TAIL((attr))) +void nl_print_policy(const struct rtattr *attr, FILE *fp); + #endif /* __LIBNETLINK_H__ */
diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index e02d6294b02e..a7b60d873afb 100644
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c@@ -28,6 +28,7 @@ #include <linux/nexthop.h> #include "libnetlink.h" +#include "utils.h" #define __aligned(x) __attribute__((aligned(x)))
@@ -1440,3 +1441,75 @@ int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, memset(tb, 0, sizeof(struct rtattr *) * (max + 1)); return 0; } + +static const char *get_nla_type_str(unsigned int attr) +{ + switch (attr) { +#define C(x) case NL_ATTR_TYPE_ ## x: return #x + C(U8); + C(U16); + C(U32); + C(U64); + C(STRING); + C(FLAG); + C(NESTED); + C(NESTED_ARRAY); + C(NUL_STRING); + C(BINARY); + C(S8); + C(S16); + C(S32); + C(S64); + C(BITFIELD32); + default: + return "unknown"; + } +} + +void nl_print_policy(const struct rtattr *attr, FILE *fp) +{ + const struct rtattr *pos; + + rtattr_for_each_nested(pos, attr) { + const struct rtattr *attr; + + fprintf(fp, " policy[%u]:", pos->rta_type & ~NLA_F_NESTED); + + rtattr_for_each_nested(attr, pos) { + struct rtattr *tp[NL_POLICY_TYPE_ATTR_MAX + 1]; + + parse_rtattr_nested(tp, ARRAY_SIZE(tp) - 1, attr); + + if (tp[NL_POLICY_TYPE_ATTR_TYPE]) + fprintf(fp, "attr[%u]: type=%s", + attr->rta_type & ~NLA_F_NESTED, + get_nla_type_str(rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_TYPE]))); + + if (tp[NL_POLICY_TYPE_ATTR_POLICY_IDX]) + fprintf(fp, " policy:%u", + rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_POLICY_IDX])); + + if (tp[NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE]) + fprintf(fp, " maxattr:%u", + rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE])); + + if (tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_S] && tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_S]) + fprintf(fp, " range:[%lld,%lld]", + (signed long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_S]), + (signed long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_S])); + + if (tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_U] && tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_U]) + fprintf(fp, " range:[%llu,%llu]", + (unsigned long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_U]), + (unsigned long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_U])); + + if (tp[NL_POLICY_TYPE_ATTR_MIN_LENGTH]) + fprintf(fp, " min len:%u", + rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_MIN_LENGTH])); + + if (tp[NL_POLICY_TYPE_ATTR_MAX_LENGTH]) + fprintf(fp, " max len:%u", + rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_MAX_LENGTH])); + } + } +}
--
2.26.2