diff options
| -rw-r--r-- | port_fwd.c | 42 |
1 files changed, 24 insertions, 18 deletions
@@ -29,8 +29,7 @@ /** * procfs_scan_listen() - Set bits for listening TCP or UDP sockets from procfs - * @fd: Pointer to fd for relevant /proc/net file - * @path: Path to /proc/net file to open (if fd is -1) + * @fd: fd for relevant /proc/net file * @lstate: Code for listening state to scan for * @map: Bitmap where numbers of ports in listening state will be set * @exclude: Bitmap of ports to exclude from setting (and clear) @@ -38,7 +37,7 @@ * #syscalls:pasta lseek * #syscalls:pasta ppc64le:_llseek ppc64:_llseek armv6l:_llseek armv7l:_llseek */ -static void procfs_scan_listen(int *fd, const char *path, unsigned int lstate, +static void procfs_scan_listen(int fd, unsigned int lstate, uint8_t *map, const uint8_t *exclude) { struct lineread lr; @@ -46,16 +45,12 @@ static void procfs_scan_listen(int *fd, const char *path, unsigned int lstate, unsigned int state; char *line; - if (*fd != -1) { - if (lseek(*fd, 0, SEEK_SET)) { - warn("lseek() failed on %s: %s", path, strerror(errno)); - return; - } - } else if ((*fd = open(path, O_RDONLY | O_CLOEXEC)) < 0) { + if (lseek(fd, 0, SEEK_SET)) { + warn("lseek() failed on /proc/net file: %s", strerror(errno)); return; } - lineread_init(&lr, *fd); + lineread_init(&lr, fd); lineread_get(&lr, &line); /* throw away header */ while (lineread_get(&lr, &line) > 0) { /* NOLINTNEXTLINE(cert-err34-c): != 2 if conversion fails */ @@ -96,20 +91,20 @@ void get_bound_ports(struct ctx *c, int ns, uint8_t proto) if (proto == IPPROTO_UDP) { memset(udp_map, 0, PORT_BITMAP_SIZE); - procfs_scan_listen(&c->proc_net_udp[V4][ns], "/proc/net/udp", + procfs_scan_listen(c->proc_net_udp[V4][ns], UDP_LISTEN, udp_map, udp_excl); - procfs_scan_listen(&c->proc_net_udp[V6][ns], "/proc/net/udp6", + procfs_scan_listen(c->proc_net_udp[V6][ns], UDP_LISTEN, udp_map, udp_excl); - procfs_scan_listen(&c->proc_net_tcp[V4][ns], "/proc/net/tcp", + procfs_scan_listen(c->proc_net_tcp[V4][ns], TCP_LISTEN, udp_map, udp_excl); - procfs_scan_listen(&c->proc_net_tcp[V6][ns], "/proc/net/tcp6", + procfs_scan_listen(c->proc_net_tcp[V6][ns], TCP_LISTEN, udp_map, udp_excl); } else if (proto == IPPROTO_TCP) { memset(tcp_map, 0, PORT_BITMAP_SIZE); - procfs_scan_listen(&c->proc_net_tcp[V4][ns], "/proc/net/tcp", + procfs_scan_listen(c->proc_net_tcp[V4][ns], TCP_LISTEN, tcp_map, tcp_excl); - procfs_scan_listen(&c->proc_net_tcp[V6][ns], "/proc/net/tcp6", + procfs_scan_listen(c->proc_net_tcp[V6][ns], TCP_LISTEN, tcp_map, tcp_excl); } } @@ -151,6 +146,7 @@ static int get_bound_ports_ns(void *arg) void port_fwd_init(struct ctx *c) { struct get_bound_ports_ns_arg ns_ports_arg = { .c = c }; + const int flags = O_RDONLY | O_CLOEXEC; c->proc_net_tcp[V4][0] = c->proc_net_tcp[V4][1] = -1; c->proc_net_tcp[V6][0] = c->proc_net_tcp[V6][1] = -1; @@ -158,15 +154,25 @@ void port_fwd_init(struct ctx *c) c->proc_net_udp[V6][0] = c->proc_net_udp[V6][1] = -1; if (c->tcp.fwd_in.mode == FWD_AUTO) { + c->proc_net_tcp[V4][1] = open_in_ns(c, "/proc/net/tcp", flags); + c->proc_net_tcp[V6][1] = open_in_ns(c, "/proc/net/tcp6", flags); ns_ports_arg.proto = IPPROTO_TCP; NS_CALL(get_bound_ports_ns, &ns_ports_arg); } if (c->udp.fwd_in.f.mode == FWD_AUTO) { + c->proc_net_udp[V4][1] = open_in_ns(c, "/proc/net/udp", flags); + c->proc_net_udp[V6][1] = open_in_ns(c, "/proc/net/udp6", flags); ns_ports_arg.proto = IPPROTO_UDP; NS_CALL(get_bound_ports_ns, &ns_ports_arg); } - if (c->tcp.fwd_out.mode == FWD_AUTO) + if (c->tcp.fwd_out.mode == FWD_AUTO) { + c->proc_net_tcp[V4][0] = open("/proc/net/tcp", flags); + c->proc_net_tcp[V6][0] = open("/proc/net/tcp6", flags); get_bound_ports(c, 0, IPPROTO_TCP); - if (c->udp.fwd_out.f.mode == FWD_AUTO) + } + if (c->udp.fwd_out.f.mode == FWD_AUTO) { + c->proc_net_udp[V4][0] = open("/proc/net/udp", flags); + c->proc_net_udp[V6][0] = open("/proc/net/udp6", flags); get_bound_ports(c, 0, IPPROTO_UDP); + } } |