--- /dev/null +++ b/ltt/ltt-control.c @@ -0,0 +1,119 @@ +/* ltt-control.c + * + * LTT control module over a netlink socket. + * + * Inspired from Relay Apps, by Tom Zanussi and iptables + * + * Copyright 2005 - + * Mathieu Desnoyers + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "ltt-control.h" + +#define LTTCTLM_BASE 0x10 +#define LTTCTLM_CONTROL (LTTCTLM_BASE + 1) /* LTT control message */ + +static struct sock *socket; + +void ltt_control_input(struct sock *sk, int len) +{ + struct sk_buff *skb; + struct nlmsghdr *nlh = NULL; + u8 *payload = NULL; + lttctl_peer_msg_t *msg; + int err; + + printk(KERN_DEBUG "ltt-control ltt_control_input\n"); + + while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { + + nlh = (struct nlmsghdr *)skb->data; + if(security_netlink_recv(skb)) { + netlink_ack(skb, nlh, EPERM); + kfree_skb(skb); + continue; + } + /* process netlink message pointed by skb->data */ + err = EINVAL; + payload = NLMSG_DATA(nlh); + /* process netlink message with header pointed by + * nlh and payload pointed by payload + */ + if(nlh->nlmsg_len != + sizeof(lttctl_peer_msg_t) + + sizeof(struct nlmsghdr)) { + printk(KERN_ALERT "ltt-control bad message length %d vs. %zu\n", + nlh->nlmsg_len, sizeof(lttctl_peer_msg_t) + + sizeof(struct nlmsghdr)); + netlink_ack(skb, nlh, EINVAL); + kfree_skb(skb); + continue; + } + msg = (lttctl_peer_msg_t*)payload; + + switch(msg->op) { + case OP_CREATE: + err = ltt_control(LTT_CONTROL_CREATE_TRACE, + msg->trace_name, + msg->trace_type, msg->args); + break; + case OP_DESTROY: + err = ltt_control(LTT_CONTROL_DESTROY_TRACE, + msg->trace_name, + msg->trace_type, msg->args); + break; + case OP_START: + err = ltt_control(LTT_CONTROL_START, + msg->trace_name, + msg->trace_type, msg->args); + break; + case OP_STOP: + err = ltt_control(LTT_CONTROL_STOP, + msg->trace_name, + msg->trace_type, msg->args); + break; + default: + err = EBADRQC; + printk(KERN_INFO + "ltt-control invalid operation\n"); + } + netlink_ack(skb, nlh, err); + kfree_skb(skb); + } +} + + +static int ltt_control_init(void) +{ + printk(KERN_INFO "ltt-control init\n"); + + socket = netlink_kernel_create(NETLINK_LTT, 1, + ltt_control_input, THIS_MODULE); + if(socket == NULL) return -EPERM; + else return 0; +} + +static void ltt_control_exit(void) +{ + printk(KERN_INFO "ltt-control exit\n"); + sock_release(socket->sk_socket); +} + + +module_init(ltt_control_init) +module_exit(ltt_control_exit) + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mathieu Desnoyers"); +MODULE_DESCRIPTION("Linux Trace Toolkit Controller"); + --- /dev/null +++ b/ltt/ltt-control.h @@ -0,0 +1,31 @@ +/* ltt-control.h + * + * LTT control module over a netlink socket. + * + * Inspired from Relay Apps, by Tom Zanussi and iptables + * + * Copyright 2005 - + * Mathieu Desnoyers + */ + +#ifndef _LTT_CONTROL_H +#define _LTT_CONTROL_H + +enum trace_op { + OP_CREATE, + OP_DESTROY, + OP_START, + OP_STOP, + OP_ALIGN, + OP_NONE +}; + +typedef struct lttctl_peer_msg { + char trace_name[NAME_MAX]; + char trace_type[NAME_MAX]; + enum trace_op op; + union ltt_control_args args; +} lttctl_peer_msg_t; + +#endif //_LTT_CONTROL_H + --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -21,6 +21,7 @@ #define NETLINK_IP6_FW 13 #define NETLINK_DNRTMSG 14 /* DECnet routing messages */ #define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */ #define NETLINK_GENERIC 16 +#define NETLINK_LTT 31 /* Linux Trace Toolkit FIXME */ #define MAX_LINKS 32