From 00e4d116a7ef94eb910be037912b0b2fc09f608b Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Fri, 22 Sep 2006 09:33:58 +0100 Subject: [PATCH 1/4] [DCCP]: Allow default/fallback service code. This has been discussed on dccp@vger and removes the necessity for applications to supply service codes in each and every case. If an application does not want to provide a service code, that's fine, it will be given 0. Otherwise, service codes can be set via socket options as before. This patch has been tested using various client/server configurations (including listening on multiple service codes). Signed-off-by: Gerrit Renker Signed-off-by: Arnaldo Carvalho de Melo --- Documentation/networking/dccp.txt | 8 +++++--- include/linux/dccp.h | 6 +----- net/dccp/ipv4.c | 3 --- net/dccp/proto.c | 11 +---------- 4 files changed, 7 insertions(+), 21 deletions(-) diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt index c45daabd3bfe..74563b38ffd9 100644 --- a/Documentation/networking/dccp.txt +++ b/Documentation/networking/dccp.txt @@ -1,7 +1,6 @@ DCCP protocol ============ -Last updated: 10 November 2005 Contents ======== @@ -42,8 +41,11 @@ Socket options DCCP_SOCKOPT_PACKET_SIZE is used for CCID3 to set default packet size for calculations. -DCCP_SOCKOPT_SERVICE sets the service. This is compulsory as per the -specification. If you don't set it you will get EPROTO. +DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of +service codes (RFC 4340, sec. 8.1.2); if this socket option is not set, +the socket will fall back to 0 (which means that no meaningful service code +is present). Connecting sockets set at most one service option; for +listening sockets, multiple service codes can be specified. Notes ===== diff --git a/include/linux/dccp.h b/include/linux/dccp.h index 2d7671c92c0b..29f9291e45c0 100644 --- a/include/linux/dccp.h +++ b/include/linux/dccp.h @@ -404,6 +404,7 @@ struct dccp_service_list { }; #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1) +#define DCCP_SERVICE_CODE_IS_ABSENT 0 static inline int dccp_list_has_service(const struct dccp_service_list *sl, const __be32 service) @@ -484,11 +485,6 @@ static inline struct dccp_minisock *dccp_msk(const struct sock *sk) return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock; } -static inline int dccp_service_not_initialized(const struct sock *sk) -{ - return dccp_sk(sk)->dccps_service == DCCP_SERVICE_INVALID_VALUE; -} - static inline const char *dccp_role(const struct sock *sk) { switch (dccp_sk(sk)->dccps_role) { diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 9a1a76a7dc41..66be29b6f508 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -56,9 +56,6 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) dp->dccps_role = DCCP_ROLE_CLIENT; - if (dccp_service_not_initialized(sk)) - return -EPROTO; - if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; diff --git a/net/dccp/proto.c b/net/dccp/proto.c index 962df0ea31aa..72cbdcfc2c65 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -217,7 +217,7 @@ int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized) icsk->icsk_sync_mss = dccp_sync_mss; dp->dccps_mss_cache = 536; dp->dccps_role = DCCP_ROLE_UNDEFINED; - dp->dccps_service = DCCP_SERVICE_INVALID_VALUE; + dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT; dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1; return 0; @@ -267,12 +267,6 @@ static inline int dccp_listen_start(struct sock *sk) struct dccp_sock *dp = dccp_sk(sk); dp->dccps_role = DCCP_ROLE_LISTEN; - /* - * Apps need to use setsockopt(DCCP_SOCKOPT_SERVICE) - * before calling listen() - */ - if (dccp_service_not_initialized(sk)) - return -EPROTO; return inet_csk_listen_start(sk, TCP_SYNQ_HSIZE); } @@ -540,9 +534,6 @@ static int dccp_getsockopt_service(struct sock *sk, int len, int err = -ENOENT, slen = 0, total_len = sizeof(u32); lock_sock(sk); - if (dccp_service_not_initialized(sk)) - goto out; - if ((sl = dp->dccps_service_list) != NULL) { slen = sl->dccpsl_nr * sizeof(u32); total_len += slen; From b83eff641ed39bd631535b9a8971e161b056f541 Mon Sep 17 00:00:00 2001 From: Ian McDonald Date: Fri, 22 Sep 2006 14:25:36 +1200 Subject: [PATCH 2/4] [DCCP]: Introduce constants for CCID numbers Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/dccp.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/include/linux/dccp.h b/include/linux/dccp.h index 29f9291e45c0..d6f4ec467a4b 100644 --- a/include/linux/dccp.h +++ b/include/linux/dccp.h @@ -169,6 +169,12 @@ enum { DCCPO_MAX_CCID_SPECIFIC = 255, }; +/* DCCP CCIDS */ +enum { + DCCPC_CCID2 = 2, + DCCPC_CCID3 = 3, +}; + /* DCCP features */ enum { DCCPF_RESERVED = 0, @@ -320,7 +326,7 @@ static inline unsigned int dccp_hdr_len(const struct sk_buff *skb) /* initial values for each feature */ #define DCCPF_INITIAL_SEQUENCE_WINDOW 100 #define DCCPF_INITIAL_ACK_RATIO 2 -#define DCCPF_INITIAL_CCID 2 +#define DCCPF_INITIAL_CCID DCCPC_CCID2 #define DCCPF_INITIAL_SEND_ACK_VECTOR 1 /* FIXME: for now we're default to 1 but it should really be 0 */ #define DCCPF_INITIAL_SEND_NDP_COUNT 1 From 3dd9a7c3a155ee96160876cba92439fdc96d7e0b Mon Sep 17 00:00:00 2001 From: Ian McDonald Date: Fri, 22 Sep 2006 14:26:44 +1200 Subject: [PATCH 3/4] [DCCP]: Use constants for CCIDs With constants for CCID numbers this now uses them in some places. Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo --- net/dccp/ccids/ccid2.c | 2 +- net/dccp/ccids/ccid3.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index 457dd3db7f41..2efb505aeb35 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -808,7 +808,7 @@ static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) } static struct ccid_operations ccid2 = { - .ccid_id = 2, + .ccid_id = DCCPC_CCID2, .ccid_name = "ccid2", .ccid_owner = THIS_MODULE, .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock), diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 195aa9566228..67d2dc0e7c67 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -1240,7 +1240,7 @@ static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, } static struct ccid_operations ccid3 = { - .ccid_id = 3, + .ccid_id = DCCPC_CCID3, .ccid_name = "ccid3", .ccid_owner = THIS_MODULE, .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), From e41542f5167d6b506607f8dd111fa0a3e468ccb8 Mon Sep 17 00:00:00 2001 From: Ian McDonald Date: Fri, 22 Sep 2006 14:28:01 +1200 Subject: [PATCH 4/4] [DCCP]: Introduce dccp_probe This adds DCCP probing shamelessly ripped off from TCP probes by Stephen Hemminger. I've put in here support for further CCID3 variables as well. Andrea/Arnaldo might look to extend for CCID2. Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo --- net/dccp/Kconfig | 16 ++++ net/dccp/Makefile | 2 + net/dccp/probe.c | 198 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 216 insertions(+) create mode 100644 net/dccp/probe.c diff --git a/net/dccp/Kconfig b/net/dccp/Kconfig index 859e3359fcda..e2a095d0fd80 100644 --- a/net/dccp/Kconfig +++ b/net/dccp/Kconfig @@ -40,6 +40,22 @@ config IP_DCCP_DEBUG Just say N. +config NET_DCCPPROBE + tristate "DCCP connection probing" + depends on PROC_FS && KPROBES + ---help--- + This module allows for capturing the changes to DCCP connection + state in response to incoming packets. It is used for debugging + DCCP congestion avoidance modules. If you don't understand + what was just said, you don't need it: say N. + + Documentation on how to use the packet generator can be found + at http://linux-net.osdl.org/index.php/DccpProbe + + To compile this code as a module, choose M here: the + module will be called dccp_probe. + + endmenu endmenu diff --git a/net/dccp/Makefile b/net/dccp/Makefile index 7696e219b05d..17ed99c46617 100644 --- a/net/dccp/Makefile +++ b/net/dccp/Makefile @@ -11,9 +11,11 @@ dccp_ipv4-y := ipv4.o dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o obj-$(CONFIG_INET_DCCP_DIAG) += dccp_diag.o +obj-$(CONFIG_NET_DCCPPROBE) += dccp_probe.o dccp-$(CONFIG_SYSCTL) += sysctl.o dccp_diag-y := diag.o +dccp_probe-y := probe.o obj-y += ccids/ diff --git a/net/dccp/probe.c b/net/dccp/probe.c new file mode 100644 index 000000000000..146496fce2e2 --- /dev/null +++ b/net/dccp/probe.c @@ -0,0 +1,198 @@ +/* + * dccp_probe - Observe the DCCP flow with kprobes. + * + * The idea for this came from Werner Almesberger's umlsim + * Copyright (C) 2004, Stephen Hemminger + * + * Modified for DCCP from Stephen Hemminger's code + * Copyright (C) 2006, Ian McDonald + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "dccp.h" +#include "ccid.h" +#include "ccids/ccid3.h" + +static int port; + +static int bufsize = 64 * 1024; + +static const char procname[] = "dccpprobe"; + +struct { + struct kfifo *fifo; + spinlock_t lock; + wait_queue_head_t wait; + struct timeval tstart; +} dccpw; + +static void printl(const char *fmt, ...) +{ + va_list args; + int len; + struct timeval now; + char tbuf[256]; + + va_start(args, fmt); + do_gettimeofday(&now); + + now.tv_sec -= dccpw.tstart.tv_sec; + now.tv_usec -= dccpw.tstart.tv_usec; + if (now.tv_usec < 0) { + --now.tv_sec; + now.tv_usec += 1000000; + } + + len = sprintf(tbuf, "%lu.%06lu ", + (unsigned long) now.tv_sec, + (unsigned long) now.tv_usec); + len += vscnprintf(tbuf+len, sizeof(tbuf)-len, fmt, args); + va_end(args); + + kfifo_put(dccpw.fifo, tbuf, len); + wake_up(&dccpw.wait); +} + +static int jdccp_sendmsg(struct kiocb *iocb, struct sock *sk, + struct msghdr *msg, size_t size) +{ + const struct dccp_minisock *dmsk = dccp_msk(sk); + const struct inet_sock *inet = inet_sk(sk); + const struct ccid3_hc_tx_sock *hctx; + + if (dmsk->dccpms_tx_ccid == DCCPC_CCID3) + hctx = ccid3_hc_tx_sk(sk); + else + hctx = NULL; + + if (port == 0 || ntohs(inet->dport) == port || + ntohs(inet->sport) == port) { + if (hctx) + printl("%d.%d.%d.%d:%u %d.%d.%d.%d:%u %d %d %d %d %d\n", + NIPQUAD(inet->saddr), ntohs(inet->sport), + NIPQUAD(inet->daddr), ntohs(inet->dport), size, + hctx->ccid3hctx_s, hctx->ccid3hctx_rtt, + hctx->ccid3hctx_p, hctx->ccid3hctx_t_ipi); + else + printl("%d.%d.%d.%d:%u %d.%d.%d.%d:%u %d\n", + NIPQUAD(inet->saddr), ntohs(inet->sport), + NIPQUAD(inet->daddr), ntohs(inet->dport), size); + } + + jprobe_return(); + return 0; +} + +static struct jprobe dccp_send_probe = { + .kp = { .addr = (kprobe_opcode_t *)&dccp_sendmsg, }, + .entry = (kprobe_opcode_t *)&jdccp_sendmsg, +}; + +static int dccpprobe_open(struct inode *inode, struct file *file) +{ + kfifo_reset(dccpw.fifo); + do_gettimeofday(&dccpw.tstart); + return 0; +} + +static ssize_t dccpprobe_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + int error = 0, cnt = 0; + unsigned char *tbuf; + + if (!buf || len < 0) + return -EINVAL; + + if (len == 0) + return 0; + + tbuf = vmalloc(len); + if (!tbuf) + return -ENOMEM; + + error = wait_event_interruptible(dccpw.wait, + __kfifo_len(dccpw.fifo) != 0); + if (error) + goto out_free; + + cnt = kfifo_get(dccpw.fifo, tbuf, len); + error = copy_to_user(buf, tbuf, cnt); + +out_free: + vfree(tbuf); + + return error ? error : cnt; +} + +static struct file_operations dccpprobe_fops = { + .owner = THIS_MODULE, + .open = dccpprobe_open, + .read = dccpprobe_read, +}; + +static __init int dccpprobe_init(void) +{ + int ret = -ENOMEM; + + init_waitqueue_head(&dccpw.wait); + spin_lock_init(&dccpw.lock); + dccpw.fifo = kfifo_alloc(bufsize, GFP_KERNEL, &dccpw.lock); + + if (!proc_net_fops_create(procname, S_IRUSR, &dccpprobe_fops)) + goto err0; + + ret = register_jprobe(&dccp_send_probe); + if (ret) + goto err1; + + pr_info("DCCP watch registered (port=%d)\n", port); + return 0; +err1: + proc_net_remove(procname); +err0: + kfifo_free(dccpw.fifo); + return ret; +} +module_init(dccpprobe_init); + +static __exit void dccpprobe_exit(void) +{ + kfifo_free(dccpw.fifo); + proc_net_remove(procname); + unregister_jprobe(&dccp_send_probe); + +} +module_exit(dccpprobe_exit); + +MODULE_PARM_DESC(port, "Port to match (0=all)"); +module_param(port, int, 0); + +MODULE_PARM_DESC(bufsize, "Log buffer size (default 64k)"); +module_param(bufsize, int, 0); + +MODULE_AUTHOR("Ian McDonald "); +MODULE_DESCRIPTION("DCCP snooper"); +MODULE_LICENSE("GPL");