diff options
Diffstat (limited to 'net/netfilter/nf_log.c')
| -rw-r--r-- | net/netfilter/nf_log.c | 155 |
1 files changed, 128 insertions, 27 deletions
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c index 85296d4eac0e..daad6022c689 100644 --- a/net/netfilter/nf_log.c +++ b/net/netfilter/nf_log.c @@ -16,16 +16,22 @@ #define NF_LOG_PREFIXLEN 128 #define NFLOGGER_NAME_LEN 64 -static struct list_head nf_loggers_l[NFPROTO_NUMPROTO] __read_mostly; +static struct nf_logger __rcu *loggers[NFPROTO_NUMPROTO][NF_LOG_TYPE_MAX] __read_mostly; static DEFINE_MUTEX(nf_log_mutex); static struct nf_logger *__find_logger(int pf, const char *str_logger) { - struct nf_logger *t; + struct nf_logger *log; + int i; + + for (i = 0; i < NF_LOG_TYPE_MAX; i++) { + if (loggers[pf][i] == NULL) + continue; - list_for_each_entry(t, &nf_loggers_l[pf], list[pf]) { - if (!strnicmp(str_logger, t->name, strlen(t->name))) - return t; + log = rcu_dereference_protected(loggers[pf][i], + lockdep_is_held(&nf_log_mutex)); + if (!strnicmp(str_logger, log->name, strlen(log->name))) + return log; } return NULL; @@ -73,17 +79,14 @@ int nf_log_register(u_int8_t pf, struct nf_logger *logger) if (pf >= ARRAY_SIZE(init_net.nf.nf_loggers)) return -EINVAL; - for (i = 0; i < ARRAY_SIZE(logger->list); i++) - INIT_LIST_HEAD(&logger->list[i]); - mutex_lock(&nf_log_mutex); if (pf == NFPROTO_UNSPEC) { for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) - list_add_tail(&(logger->list[i]), &(nf_loggers_l[i])); + rcu_assign_pointer(loggers[i][logger->type], logger); } else { /* register at end of list to honor first register win */ - list_add_tail(&logger->list[pf], &nf_loggers_l[pf]); + rcu_assign_pointer(loggers[pf][logger->type], logger); } mutex_unlock(&nf_log_mutex); @@ -98,7 +101,7 @@ void nf_log_unregister(struct nf_logger *logger) mutex_lock(&nf_log_mutex); for (i = 0; i < NFPROTO_NUMPROTO; i++) - list_del(&logger->list[i]); + RCU_INIT_POINTER(loggers[i][logger->type], NULL); mutex_unlock(&nf_log_mutex); } EXPORT_SYMBOL(nf_log_unregister); @@ -129,6 +132,48 @@ void nf_log_unbind_pf(struct net *net, u_int8_t pf) } EXPORT_SYMBOL(nf_log_unbind_pf); +void nf_logger_request_module(int pf, enum nf_log_type type) +{ + if (loggers[pf][type] == NULL) + request_module("nf-logger-%u-%u", pf, type); +} +EXPORT_SYMBOL_GPL(nf_logger_request_module); + +int nf_logger_find_get(int pf, enum nf_log_type type) +{ + struct nf_logger *logger; + int ret = -ENOENT; + + logger = loggers[pf][type]; + if (logger == NULL) + request_module("nf-logger-%u-%u", pf, type); + + rcu_read_lock(); + logger = rcu_dereference(loggers[pf][type]); + if (logger == NULL) + goto out; + + if (logger && try_module_get(logger->me)) + ret = 0; +out: + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(nf_logger_find_get); + +void nf_logger_put(int pf, enum nf_log_type type) +{ + struct nf_logger *logger; + + BUG_ON(loggers[pf][type] == NULL); + + rcu_read_lock(); + logger = rcu_dereference(loggers[pf][type]); + module_put(logger->me); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(nf_logger_put); + void nf_log_packet(struct net *net, u_int8_t pf, unsigned int hooknum, @@ -143,7 +188,11 @@ void nf_log_packet(struct net *net, const struct nf_logger *logger; rcu_read_lock(); - logger = rcu_dereference(net->nf.nf_loggers[pf]); + if (loginfo != NULL) + logger = rcu_dereference(loggers[pf][loginfo->type]); + else + logger = rcu_dereference(net->nf.nf_loggers[pf]); + if (logger) { va_start(args, fmt); vsnprintf(prefix, sizeof(prefix), fmt, args); @@ -154,6 +203,63 @@ void nf_log_packet(struct net *net, } EXPORT_SYMBOL(nf_log_packet); +#define S_SIZE (1024 - (sizeof(unsigned int) + 1)) + +struct nf_log_buf { + unsigned int count; + char buf[S_SIZE + 1]; +}; +static struct nf_log_buf emergency, *emergency_ptr = &emergency; + +__printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...) +{ + va_list args; + int len; + + if (likely(m->count < S_SIZE)) { + va_start(args, f); + len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args); + va_end(args); + if (likely(m->count + len < S_SIZE)) { + m->count += len; + return 0; + } + } + m->count = S_SIZE; + printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n"); + return -1; +} +EXPORT_SYMBOL_GPL(nf_log_buf_add); + +struct nf_log_buf *nf_log_buf_open(void) +{ + struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC); + + if (unlikely(!m)) { + local_bh_disable(); + do { + m = xchg(&emergency_ptr, NULL); + } while (!m); + } + m->count = 0; + return m; +} +EXPORT_SYMBOL_GPL(nf_log_buf_open); + +void nf_log_buf_close(struct nf_log_buf *m) +{ + m->buf[m->count] = 0; + printk("%s\n", m->buf); + + if (likely(m != &emergency)) + kfree(m); + else { + emergency_ptr = m; + local_bh_enable(); + } +} +EXPORT_SYMBOL_GPL(nf_log_buf_close); + #ifdef CONFIG_PROC_FS static void *seq_start(struct seq_file *seq, loff_t *pos) { @@ -188,8 +294,7 @@ static int seq_show(struct seq_file *s, void *v) { loff_t *pos = v; const struct nf_logger *logger; - struct nf_logger *t; - int ret; + int i, ret; struct net *net = seq_file_net(s); logger = rcu_dereference_protected(net->nf.nf_loggers[*pos], @@ -203,11 +308,16 @@ static int seq_show(struct seq_file *s, void *v) if (ret < 0) return ret; - list_for_each_entry(t, &nf_loggers_l[*pos], list[*pos]) { - ret = seq_printf(s, "%s", t->name); + for (i = 0; i < NF_LOG_TYPE_MAX; i++) { + if (loggers[*pos][i] == NULL) + continue; + + logger = rcu_dereference_protected(loggers[*pos][i], + lockdep_is_held(&nf_log_mutex)); + ret = seq_printf(s, "%s", logger->name); if (ret < 0) return ret; - if (&t->list[*pos] != nf_loggers_l[*pos].prev) { + if (i == 0 && loggers[*pos][i + 1] != NULL) { ret = seq_printf(s, ","); if (ret < 0) return ret; @@ -389,14 +499,5 @@ static struct pernet_operations nf_log_net_ops = { int __init netfilter_log_init(void) { - int i, ret; - - ret = register_pernet_subsys(&nf_log_net_ops); - if (ret < 0) - return ret; - - for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) - INIT_LIST_HEAD(&(nf_loggers_l[i])); - - return 0; + return register_pernet_subsys(&nf_log_net_ops); } |