A few updates on the hook listing support: - Group hooks by family, e.g. ip - Group hooks by number, e.g. input. - Order hooks by priority, from INT_MIN to INT_MAX. - Do not add sign to hook number zero. - Ignore EPROTONOSUPPORT, on older kernels this command results in EINVAL. On new kernels, just list nothing on unsupported families. # nft list hooks family ip { hook input { -0000000100 nft_do_chain_ipv4 [nf_tables [nf_tables] # nft table ip x chain z 0000000000 nft_do_chain_ipv4 [nf_tables [nf_tables] # nft table ip x chain y +0000000100 nft_do_chain_ipv4 [nf_tables [nf_tables] # nft table ip x chain w +0000000300 nft_do_chain_inet [nf_tables [nf_tables] # nft table ip x chain y } hook forward { -0000000225 selinux_ipv4_forward } hook output { -0000000225 selinux_ipv4_output } hook postrouting { +0000000225 selinux_ipv4_postroute } } family ip6 { hook input { +0000000300 nft_do_chain_inet [nf_tables [nf_tables] # nft table ip6 x chain y } hook forward { -0000000225 selinux_ipv6_forward } hook output { -0000000225 selinux_ipv6_output } hook postrouting { +0000000225 selinux_ipv6_postroute } } Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- src/mnl.c | 333 ++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 246 insertions(+), 87 deletions(-) diff --git a/src/mnl.c b/src/mnl.c index f28d6605835f..a0176443ace6 100644 --- a/src/mnl.c +++ b/src/mnl.c @@ -44,6 +44,9 @@ struct basehook { const char *hookfn; const char *table; const char *chain; + const char *devname; + int family; + uint32_t num; int prio; }; @@ -1942,12 +1945,27 @@ static void basehook_free(struct basehook *b) xfree(b->module_name); xfree(b->hookfn); xfree(b->chain); + xfree(b->devname); xfree(b->table); xfree(b); } static void basehook_list_add_tail(struct basehook *b, struct list_head *head) { + struct basehook *hook; + + list_for_each_entry(hook, head, list) { + if (hook->family != b->family) + continue; + if (hook->num != b->num) + continue; + if (hook->prio < b->prio) + continue; + + list_add(&b->list, &hook->list); + return; + } + list_add_tail(&b->list, head); } @@ -2033,11 +2051,18 @@ static int dump_nf_attr_chain_cb(const struct nlattr *attr, void *data) return MNL_CB_OK; } -static int dump_nf_hooks(const struct nlmsghdr *nlh, void *data) +struct dump_nf_hook_data { + struct list_head *hook_list; + const char *devname; + int family; + uint32_t hooknum; +}; + +static int dump_nf_hooks(const struct nlmsghdr *nlh, void *_data) { const struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh); struct nlattr *tb[NFNLA_HOOK_MAX + 1] = {}; - struct list_head *head = data; + struct dump_nf_hook_data *data = _data; struct basehook *hook; /* NB: Don't check the nft generation ID, this is not @@ -2079,10 +2104,14 @@ static int dump_nf_hooks(const struct nlmsghdr *nlh, void *data) hook->table = xstrdup(tablename); hook->chain = xstrdup(chainname); } + if (data->devname) + hook->devname = xstrdup(data->devname); } } + hook->num = data->hooknum; + hook->family = data->family; - basehook_list_add_tail(hook, head); + basehook_list_add_tail(hook, data->hook_list); return MNL_CB_OK; } @@ -2102,14 +2131,17 @@ static struct nlmsghdr *nf_hook_dump_request(char *buf, uint8_t family, uint32_t return nlh; } -static int __mnl_nft_dump_nf_hooks(struct netlink_ctx *ctx, uint8_t family, uint8_t hooknum, const char *devname) +static int __mnl_nft_dump_nf_hooks(struct netlink_ctx *ctx, uint8_t family, uint8_t hooknum, const char *devname, + struct list_head *hook_list) { char buf[MNL_SOCKET_BUFFER_SIZE]; - struct basehook *hook, *tmp; + struct dump_nf_hook_data data = { + .hook_list = hook_list, + .devname = devname, + .family = family, + .hooknum = hooknum, + }; struct nlmsghdr *nlh; - LIST_HEAD(hook_list); - FILE *fp; - int ret; nlh = nf_hook_dump_request(buf, family, ctx->seqnum); if (devname) @@ -2117,27 +2149,63 @@ static int __mnl_nft_dump_nf_hooks(struct netlink_ctx *ctx, uint8_t family, uint mnl_attr_put_u32(nlh, NFNLA_HOOK_HOOKNUM, htonl(hooknum)); - ret = nft_mnl_talk(ctx, nlh, nlh->nlmsg_len, dump_nf_hooks, &hook_list); - if (ret) - return ret; + return nft_mnl_talk(ctx, nlh, nlh->nlmsg_len, dump_nf_hooks, &data); +} - if (list_empty(&hook_list)) - return 0; +static void print_hooks(struct netlink_ctx *ctx, int family, struct list_head *hook_list) +{ + struct basehook *hook, *tmp, *prev = NULL; + bool same, family_in_use = false; + int prio; + FILE *fp; fp = ctx->nft->output.output_fp; - fprintf(fp, "family %s hook %s", family2str(family), hooknum2str(family, hooknum)); - if (devname) - fprintf(fp, " device %s", devname); - fprintf(fp, " {\n"); + list_for_each_entry_safe(hook, tmp, hook_list, list) { + if (hook->family == family) { + family_in_use = true; + break; + } + } + + if (!family_in_use) + return; - list_for_each_entry_safe(hook, tmp, &hook_list, list) { - int prio = hook->prio; + fprintf(fp, "family %s {\n", family2str(family)); + list_for_each_entry_safe(hook, tmp, hook_list, list) { + if (hook->family != family) + continue; + + if (prev) { + if (prev->num == hook->num) { + fprintf(fp, "\n"); + same = true; + } else { + same = false; + fprintf(fp, "\n\t}\n"); + } + } else { + same = false; + } + prev = hook; + + if (!same) { + if (hook->devname) + fprintf(fp, "\thook %s device %s {\n", + hooknum2str(family, hook->num), hook->devname); + else + fprintf(fp, "\thook %s {\n", + hooknum2str(family, hook->num)); + } + + prio = hook->prio; if (prio < 0) - fprintf(fp, "\t%011d", prio); /* outputs a '-' sign */ + fprintf(fp, "\t\t%011d", prio); /* outputs a '-' sign */ + else if (prio == 0) + fprintf(fp, "\t\t %010u", prio); else - fprintf(fp, "\t+%010u", prio); + fprintf(fp, "\t\t+%010u", prio); if (hook->hookfn) { fprintf(fp, " %s", hook->hookfn); @@ -2147,100 +2215,191 @@ static int __mnl_nft_dump_nf_hooks(struct netlink_ctx *ctx, uint8_t family, uint if (hook->table && hook->chain) fprintf(fp, "\t# nft table %s %s chain %s", family2str(family), hook->table, hook->chain); - - fprintf(fp, "\n"); - basehook_free(hook); } + fprintf(fp, "\n\t}\n"); fprintf(fp, "}\n"); - return ret; +} + +#define HOOK_FAMILY_MAX 5 + +static uint8_t hook_family[HOOK_FAMILY_MAX] = { + NFPROTO_IPV4, + NFPROTO_IPV6, + NFPROTO_BRIDGE, + NFPROTO_ARP, +}; + +static int mnl_nft_dump_nf_inet(struct netlink_ctx *ctx, int family, int hook, + const char *devname, struct list_head *hook_list, + int *ret) +{ + int err; + + if (devname) { + err = __mnl_nft_dump_nf_hooks(ctx, family, NF_INET_INGRESS, devname, hook_list); + if (err < 0) + *ret = err; + } + + err = __mnl_nft_dump_nf_hooks(ctx, NFPROTO_IPV4, hook, NULL, hook_list); + if (err < 0) + *ret = err; + err = __mnl_nft_dump_nf_hooks(ctx, NFPROTO_IPV6, hook, NULL, hook_list); + if (err < 0) + *ret = err; + + return err; +} + +static int mnl_nft_dump_nf(struct netlink_ctx *ctx, int family, int hook, + const char *devname, struct list_head *hook_list, + int *ret) +{ + int i, err; + + if (hook >= 0) { + err = __mnl_nft_dump_nf_hooks(ctx, family, hook, devname, hook_list); + if (err < 0) + *ret = err; + + return err; + } + + for (i = 0; i <= NF_INET_POST_ROUTING; i++) { + err = __mnl_nft_dump_nf_hooks(ctx, family, i, NULL, hook_list); + if (err < 0) + *ret = err; + } + + return err; +} + +static int mnl_nft_dump_nf_arp(struct netlink_ctx *ctx, int family, int hook, + const char *devname, struct list_head *hook_list, + int *ret) +{ + int err; + + if (hook >= 0) { + err = __mnl_nft_dump_nf_hooks(ctx, family, hook, devname, hook_list); + if (err < 0) + *ret = err; + + return err; + } + + err = __mnl_nft_dump_nf_hooks(ctx, family, NF_ARP_IN, devname, hook_list); + if (err < 0) + *ret = err; + err = __mnl_nft_dump_nf_hooks(ctx, family, NF_ARP_OUT, devname, hook_list); + if (err < 0) + *ret = err; + + return err; +} + +static int mnl_nft_dump_nf_netdev(struct netlink_ctx *ctx, int family, int hook, + const char *devname, struct list_head *hook_list, + int *ret) +{ + int err; + + if (hook >= 0) { + err = __mnl_nft_dump_nf_hooks(ctx, family, hook, devname, hook_list); + if (err < 0) + *ret = err; + + return err; + } + + err = __mnl_nft_dump_nf_hooks(ctx, family, NF_INET_INGRESS, devname, hook_list); + if (err < 0) + *ret = err; + + return err; +} + +static int mnl_nft_dump_nf_decnet(struct netlink_ctx *ctx, int family, int hook, + const char *devname, struct list_head *hook_list, + int *ret) +{ + int i, err; + + if (hook >= 0) { + err = __mnl_nft_dump_nf_hooks(ctx, family, hook, devname, hook_list); + if (err < 0) + *ret = err; + + return err; + } +#define NF_DN_NUMHOOKS 7 + for (i = 0; i < NF_DN_NUMHOOKS; i++) { + err = __mnl_nft_dump_nf_hooks(ctx, family, i, devname, hook_list); + if (err < 0) { + *ret = err; + return err; + } + } + + return err; +} + +static void release_hook_list(struct list_head *hook_list) +{ + struct basehook *hook, *next; + + list_for_each_entry_safe(hook, next, hook_list, list) + basehook_free(hook); } int mnl_nft_dump_nf_hooks(struct netlink_ctx *ctx, int family, int hook, const char *devname) { + LIST_HEAD(hook_list); unsigned int i; - int ret, err; + int ret; errno = 0; ret = 0; switch (family) { case NFPROTO_UNSPEC: - if (devname) - return mnl_nft_dump_nf_hooks(ctx, NFPROTO_NETDEV, NF_INET_INGRESS, devname); - - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_INET, hook, NULL); - if (err < 0 && errno != EPROTONOSUPPORT) - ret = err; - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_ARP, hook, NULL); - if (err < 0 && errno != EPROTONOSUPPORT) - ret = err; - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_BRIDGE, hook, NULL); - if (err < 0 && errno != EPROTONOSUPPORT) - ret = err; - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_DECNET, hook, NULL); - if (err < 0 && errno != EPROTONOSUPPORT) - ret = err; + mnl_nft_dump_nf_netdev(ctx, NFPROTO_NETDEV, hook, devname, &hook_list, &ret); + mnl_nft_dump_nf_inet(ctx, NFPROTO_INET, hook, devname, &hook_list, &ret); + mnl_nft_dump_nf(ctx, NFPROTO_IPV4, hook, devname, &hook_list, &ret); + mnl_nft_dump_nf(ctx, NFPROTO_IPV6, hook, devname, &hook_list, &ret); + mnl_nft_dump_nf(ctx, NFPROTO_BRIDGE, hook, devname, &hook_list, &ret); + mnl_nft_dump_nf_decnet(ctx, NFPROTO_DECNET, hook, devname, &hook_list, &ret); break; case NFPROTO_INET: - if (devname) { - err = __mnl_nft_dump_nf_hooks(ctx, family, NF_INET_INGRESS, devname); - if (err < 0) - ret = err; - } - - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_IPV4, hook, NULL); - if (err < 0) - ret = err; - err = mnl_nft_dump_nf_hooks(ctx, NFPROTO_IPV6, hook, NULL); - if (err < 0) - ret = err; - + mnl_nft_dump_nf_inet(ctx, family, hook, devname, &hook_list, &ret); break; case NFPROTO_IPV4: case NFPROTO_IPV6: case NFPROTO_BRIDGE: - if (hook >= 0) - return __mnl_nft_dump_nf_hooks(ctx, family, hook, devname); - - for (i = 0; i <= NF_INET_POST_ROUTING; i++) { - err = __mnl_nft_dump_nf_hooks(ctx, family, i, NULL); - if (err < 0) - err = ret; - } + mnl_nft_dump_nf(ctx, family, hook, devname, &hook_list, &ret); break; case NFPROTO_ARP: - if (hook >= 0) - return __mnl_nft_dump_nf_hooks(ctx, family, hook, devname); - - err = __mnl_nft_dump_nf_hooks(ctx, family, NF_ARP_IN, devname); - if (err < 0) - ret = err; - err = __mnl_nft_dump_nf_hooks(ctx, family, NF_ARP_OUT, devname); - if (err < 0) - ret = err; + mnl_nft_dump_nf_arp(ctx, family, hook, devname, &hook_list, &ret); break; case NFPROTO_NETDEV: - if (hook >= 0) - return __mnl_nft_dump_nf_hooks(ctx, family, hook, devname); - - err = __mnl_nft_dump_nf_hooks(ctx, family, NF_INET_INGRESS, devname); - if (err < 0) - ret = err; + mnl_nft_dump_nf_netdev(ctx, family, hook, devname, &hook_list, &ret); break; case NFPROTO_DECNET: - if (hook >= 0) - return __mnl_nft_dump_nf_hooks(ctx, family, hook, devname); -#define NF_DN_NUMHOOKS 7 - for (i = 0; i < NF_DN_NUMHOOKS; i++) { - err = __mnl_nft_dump_nf_hooks(ctx, family, i, devname); - if (err < 0) { - ret = err; - break; - } - } + mnl_nft_dump_nf_decnet(ctx, family, hook, devname, &hook_list, &ret); break; } + if (family == NFPROTO_UNSPEC) { + for (i = 0; i < HOOK_FAMILY_MAX; i++) { + print_hooks(ctx, hook_family[i], &hook_list); + } + } else { + print_hooks(ctx, family, &hook_list); + } + + release_hook_list(&hook_list); + ret = 0; + return ret; } -- 2.20.1