![Sasha Levin](/assets/img/avatar_default.png)
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1738 lines
48 KiB
C
1738 lines
48 KiB
C
/* SIP extension for IP connection tracking.
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*
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* (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
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* based on RR's ip_conntrack_ftp.c and other modules.
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* (C) 2007 United Security Providers
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* (C) 2007, 2008 Patrick McHardy <kaber@trash.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/ctype.h>
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#include <linux/skbuff.h>
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#include <linux/inet.h>
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#include <linux/in.h>
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#include <linux/udp.h>
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#include <linux/tcp.h>
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#include <linux/netfilter.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_conntrack_expect.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <net/netfilter/nf_conntrack_zones.h>
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#include <linux/netfilter/nf_conntrack_sip.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>");
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MODULE_DESCRIPTION("SIP connection tracking helper");
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MODULE_ALIAS("ip_conntrack_sip");
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MODULE_ALIAS_NFCT_HELPER("sip");
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#define MAX_PORTS 8
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static unsigned short ports[MAX_PORTS];
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static unsigned int ports_c;
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module_param_array(ports, ushort, &ports_c, 0400);
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MODULE_PARM_DESC(ports, "port numbers of SIP servers");
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static unsigned int sip_timeout __read_mostly = SIP_TIMEOUT;
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module_param(sip_timeout, uint, 0600);
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MODULE_PARM_DESC(sip_timeout, "timeout for the master SIP session");
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static int sip_direct_signalling __read_mostly = 1;
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module_param(sip_direct_signalling, int, 0600);
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MODULE_PARM_DESC(sip_direct_signalling, "expect incoming calls from registrar "
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"only (default 1)");
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static int sip_direct_media __read_mostly = 1;
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module_param(sip_direct_media, int, 0600);
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MODULE_PARM_DESC(sip_direct_media, "Expect Media streams between signalling "
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"endpoints only (default 1)");
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unsigned int (*nf_nat_sip_hook)(struct sk_buff *skb, unsigned int protoff,
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unsigned int dataoff, const char **dptr,
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unsigned int *datalen) __read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sip_hook);
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void (*nf_nat_sip_seq_adjust_hook)(struct sk_buff *skb, unsigned int protoff,
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s16 off) __read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sip_seq_adjust_hook);
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unsigned int (*nf_nat_sip_expect_hook)(struct sk_buff *skb,
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unsigned int protoff,
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unsigned int dataoff,
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const char **dptr,
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unsigned int *datalen,
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struct nf_conntrack_expect *exp,
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unsigned int matchoff,
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unsigned int matchlen) __read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sip_expect_hook);
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unsigned int (*nf_nat_sdp_addr_hook)(struct sk_buff *skb, unsigned int protoff,
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unsigned int dataoff,
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const char **dptr,
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unsigned int *datalen,
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unsigned int sdpoff,
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enum sdp_header_types type,
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enum sdp_header_types term,
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const union nf_inet_addr *addr)
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__read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sdp_addr_hook);
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unsigned int (*nf_nat_sdp_port_hook)(struct sk_buff *skb, unsigned int protoff,
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unsigned int dataoff,
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const char **dptr,
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unsigned int *datalen,
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unsigned int matchoff,
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unsigned int matchlen,
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u_int16_t port) __read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sdp_port_hook);
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unsigned int (*nf_nat_sdp_session_hook)(struct sk_buff *skb,
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unsigned int protoff,
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unsigned int dataoff,
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const char **dptr,
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unsigned int *datalen,
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unsigned int sdpoff,
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const union nf_inet_addr *addr)
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__read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sdp_session_hook);
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unsigned int (*nf_nat_sdp_media_hook)(struct sk_buff *skb, unsigned int protoff,
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unsigned int dataoff,
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const char **dptr,
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unsigned int *datalen,
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struct nf_conntrack_expect *rtp_exp,
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struct nf_conntrack_expect *rtcp_exp,
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unsigned int mediaoff,
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unsigned int medialen,
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union nf_inet_addr *rtp_addr)
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__read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_sdp_media_hook);
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static int string_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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int len = 0;
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while (dptr < limit && isalpha(*dptr)) {
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dptr++;
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len++;
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}
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return len;
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}
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static int digits_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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int len = 0;
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while (dptr < limit && isdigit(*dptr)) {
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dptr++;
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len++;
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}
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return len;
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}
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static int iswordc(const char c)
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{
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if (isalnum(c) || c == '!' || c == '"' || c == '%' ||
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(c >= '(' && c <= '/') || c == ':' || c == '<' || c == '>' ||
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c == '?' || (c >= '[' && c <= ']') || c == '_' || c == '`' ||
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c == '{' || c == '}' || c == '~')
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return 1;
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return 0;
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}
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static int word_len(const char *dptr, const char *limit)
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{
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int len = 0;
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while (dptr < limit && iswordc(*dptr)) {
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dptr++;
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len++;
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}
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return len;
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}
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static int callid_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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int len, domain_len;
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len = word_len(dptr, limit);
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dptr += len;
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if (!len || dptr == limit || *dptr != '@')
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return len;
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dptr++;
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len++;
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domain_len = word_len(dptr, limit);
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if (!domain_len)
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return 0;
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return len + domain_len;
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}
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/* get media type + port length */
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static int media_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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int len = string_len(ct, dptr, limit, shift);
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dptr += len;
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if (dptr >= limit || *dptr != ' ')
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return 0;
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len++;
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dptr++;
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return len + digits_len(ct, dptr, limit, shift);
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}
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static int sip_parse_addr(const struct nf_conn *ct, const char *cp,
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const char **endp, union nf_inet_addr *addr,
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const char *limit, bool delim)
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{
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const char *end;
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int ret;
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if (!ct)
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return 0;
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memset(addr, 0, sizeof(*addr));
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switch (nf_ct_l3num(ct)) {
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case AF_INET:
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ret = in4_pton(cp, limit - cp, (u8 *)&addr->ip, -1, &end);
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if (ret == 0)
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return 0;
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break;
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case AF_INET6:
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if (cp < limit && *cp == '[')
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cp++;
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else if (delim)
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return 0;
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ret = in6_pton(cp, limit - cp, (u8 *)&addr->ip6, -1, &end);
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if (ret == 0)
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return 0;
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if (end < limit && *end == ']')
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end++;
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else if (delim)
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return 0;
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break;
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default:
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BUG();
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}
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if (endp)
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*endp = end;
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return 1;
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}
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/* skip ip address. returns its length. */
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static int epaddr_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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union nf_inet_addr addr;
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const char *aux = dptr;
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if (!sip_parse_addr(ct, dptr, &dptr, &addr, limit, true)) {
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pr_debug("ip: %s parse failed.!\n", dptr);
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return 0;
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}
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/* Port number */
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if (*dptr == ':') {
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dptr++;
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dptr += digits_len(ct, dptr, limit, shift);
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}
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return dptr - aux;
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}
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/* get address length, skiping user info. */
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static int skp_epaddr_len(const struct nf_conn *ct, const char *dptr,
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const char *limit, int *shift)
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{
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const char *start = dptr;
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int s = *shift;
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/* Search for @, but stop at the end of the line.
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* We are inside a sip: URI, so we don't need to worry about
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* continuation lines. */
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while (dptr < limit &&
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*dptr != '@' && *dptr != '\r' && *dptr != '\n') {
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(*shift)++;
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dptr++;
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}
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if (dptr < limit && *dptr == '@') {
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dptr++;
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(*shift)++;
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} else {
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dptr = start;
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*shift = s;
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}
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return epaddr_len(ct, dptr, limit, shift);
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}
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/* Parse a SIP request line of the form:
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*
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* Request-Line = Method SP Request-URI SP SIP-Version CRLF
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*
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* and return the offset and length of the address contained in the Request-URI.
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*/
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int ct_sip_parse_request(const struct nf_conn *ct,
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const char *dptr, unsigned int datalen,
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unsigned int *matchoff, unsigned int *matchlen,
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union nf_inet_addr *addr, __be16 *port)
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{
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const char *start = dptr, *limit = dptr + datalen, *end;
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unsigned int mlen;
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unsigned int p;
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int shift = 0;
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/* Skip method and following whitespace */
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mlen = string_len(ct, dptr, limit, NULL);
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if (!mlen)
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return 0;
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dptr += mlen;
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if (++dptr >= limit)
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return 0;
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/* Find SIP URI */
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for (; dptr < limit - strlen("sip:"); dptr++) {
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if (*dptr == '\r' || *dptr == '\n')
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return -1;
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if (strnicmp(dptr, "sip:", strlen("sip:")) == 0) {
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dptr += strlen("sip:");
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break;
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}
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}
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if (!skp_epaddr_len(ct, dptr, limit, &shift))
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return 0;
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dptr += shift;
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if (!sip_parse_addr(ct, dptr, &end, addr, limit, true))
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return -1;
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if (end < limit && *end == ':') {
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end++;
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p = simple_strtoul(end, (char **)&end, 10);
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if (p < 1024 || p > 65535)
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return -1;
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*port = htons(p);
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} else
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*port = htons(SIP_PORT);
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if (end == dptr)
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return 0;
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*matchoff = dptr - start;
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*matchlen = end - dptr;
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return 1;
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}
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EXPORT_SYMBOL_GPL(ct_sip_parse_request);
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/* SIP header parsing: SIP headers are located at the beginning of a line, but
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* may span several lines, in which case the continuation lines begin with a
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* whitespace character. RFC 2543 allows lines to be terminated with CR, LF or
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* CRLF, RFC 3261 allows only CRLF, we support both.
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*
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* Headers are followed by (optionally) whitespace, a colon, again (optionally)
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* whitespace and the values. Whitespace in this context means any amount of
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* tabs, spaces and continuation lines, which are treated as a single whitespace
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* character.
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*
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* Some headers may appear multiple times. A comma separated list of values is
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* equivalent to multiple headers.
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*/
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static const struct sip_header ct_sip_hdrs[] = {
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[SIP_HDR_CSEQ] = SIP_HDR("CSeq", NULL, NULL, digits_len),
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[SIP_HDR_FROM] = SIP_HDR("From", "f", "sip:", skp_epaddr_len),
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[SIP_HDR_TO] = SIP_HDR("To", "t", "sip:", skp_epaddr_len),
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[SIP_HDR_CONTACT] = SIP_HDR("Contact", "m", "sip:", skp_epaddr_len),
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[SIP_HDR_VIA_UDP] = SIP_HDR("Via", "v", "UDP ", epaddr_len),
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[SIP_HDR_VIA_TCP] = SIP_HDR("Via", "v", "TCP ", epaddr_len),
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[SIP_HDR_EXPIRES] = SIP_HDR("Expires", NULL, NULL, digits_len),
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[SIP_HDR_CONTENT_LENGTH] = SIP_HDR("Content-Length", "l", NULL, digits_len),
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[SIP_HDR_CALL_ID] = SIP_HDR("Call-Id", "i", NULL, callid_len),
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};
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static const char *sip_follow_continuation(const char *dptr, const char *limit)
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{
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/* Walk past newline */
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if (++dptr >= limit)
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return NULL;
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/* Skip '\n' in CR LF */
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if (*(dptr - 1) == '\r' && *dptr == '\n') {
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if (++dptr >= limit)
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return NULL;
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}
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/* Continuation line? */
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if (*dptr != ' ' && *dptr != '\t')
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return NULL;
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/* skip leading whitespace */
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for (; dptr < limit; dptr++) {
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if (*dptr != ' ' && *dptr != '\t')
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break;
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}
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return dptr;
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}
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static const char *sip_skip_whitespace(const char *dptr, const char *limit)
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{
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for (; dptr < limit; dptr++) {
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if (*dptr == ' ')
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continue;
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if (*dptr != '\r' && *dptr != '\n')
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break;
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dptr = sip_follow_continuation(dptr, limit);
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if (dptr == NULL)
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return NULL;
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}
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return dptr;
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}
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/* Search within a SIP header value, dealing with continuation lines */
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static const char *ct_sip_header_search(const char *dptr, const char *limit,
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const char *needle, unsigned int len)
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{
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for (limit -= len; dptr < limit; dptr++) {
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if (*dptr == '\r' || *dptr == '\n') {
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dptr = sip_follow_continuation(dptr, limit);
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if (dptr == NULL)
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break;
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continue;
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}
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if (strnicmp(dptr, needle, len) == 0)
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return dptr;
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}
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return NULL;
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}
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int ct_sip_get_header(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
enum sip_header_types type,
|
|
unsigned int *matchoff, unsigned int *matchlen)
|
|
{
|
|
const struct sip_header *hdr = &ct_sip_hdrs[type];
|
|
const char *start = dptr, *limit = dptr + datalen;
|
|
int shift = 0;
|
|
|
|
for (dptr += dataoff; dptr < limit; dptr++) {
|
|
/* Find beginning of line */
|
|
if (*dptr != '\r' && *dptr != '\n')
|
|
continue;
|
|
if (++dptr >= limit)
|
|
break;
|
|
if (*(dptr - 1) == '\r' && *dptr == '\n') {
|
|
if (++dptr >= limit)
|
|
break;
|
|
}
|
|
|
|
/* Skip continuation lines */
|
|
if (*dptr == ' ' || *dptr == '\t')
|
|
continue;
|
|
|
|
/* Find header. Compact headers must be followed by a
|
|
* non-alphabetic character to avoid mismatches. */
|
|
if (limit - dptr >= hdr->len &&
|
|
strnicmp(dptr, hdr->name, hdr->len) == 0)
|
|
dptr += hdr->len;
|
|
else if (hdr->cname && limit - dptr >= hdr->clen + 1 &&
|
|
strnicmp(dptr, hdr->cname, hdr->clen) == 0 &&
|
|
!isalpha(*(dptr + hdr->clen)))
|
|
dptr += hdr->clen;
|
|
else
|
|
continue;
|
|
|
|
/* Find and skip colon */
|
|
dptr = sip_skip_whitespace(dptr, limit);
|
|
if (dptr == NULL)
|
|
break;
|
|
if (*dptr != ':' || ++dptr >= limit)
|
|
break;
|
|
|
|
/* Skip whitespace after colon */
|
|
dptr = sip_skip_whitespace(dptr, limit);
|
|
if (dptr == NULL)
|
|
break;
|
|
|
|
*matchoff = dptr - start;
|
|
if (hdr->search) {
|
|
dptr = ct_sip_header_search(dptr, limit, hdr->search,
|
|
hdr->slen);
|
|
if (!dptr)
|
|
return -1;
|
|
dptr += hdr->slen;
|
|
}
|
|
|
|
*matchlen = hdr->match_len(ct, dptr, limit, &shift);
|
|
if (!*matchlen)
|
|
return -1;
|
|
*matchoff = dptr - start + shift;
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ct_sip_get_header);
|
|
|
|
/* Get next header field in a list of comma separated values */
|
|
static int ct_sip_next_header(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
enum sip_header_types type,
|
|
unsigned int *matchoff, unsigned int *matchlen)
|
|
{
|
|
const struct sip_header *hdr = &ct_sip_hdrs[type];
|
|
const char *start = dptr, *limit = dptr + datalen;
|
|
int shift = 0;
|
|
|
|
dptr += dataoff;
|
|
|
|
dptr = ct_sip_header_search(dptr, limit, ",", strlen(","));
|
|
if (!dptr)
|
|
return 0;
|
|
|
|
dptr = ct_sip_header_search(dptr, limit, hdr->search, hdr->slen);
|
|
if (!dptr)
|
|
return 0;
|
|
dptr += hdr->slen;
|
|
|
|
*matchoff = dptr - start;
|
|
*matchlen = hdr->match_len(ct, dptr, limit, &shift);
|
|
if (!*matchlen)
|
|
return -1;
|
|
*matchoff += shift;
|
|
return 1;
|
|
}
|
|
|
|
/* Walk through headers until a parsable one is found or no header of the
|
|
* given type is left. */
|
|
static int ct_sip_walk_headers(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
enum sip_header_types type, int *in_header,
|
|
unsigned int *matchoff, unsigned int *matchlen)
|
|
{
|
|
int ret;
|
|
|
|
if (in_header && *in_header) {
|
|
while (1) {
|
|
ret = ct_sip_next_header(ct, dptr, dataoff, datalen,
|
|
type, matchoff, matchlen);
|
|
if (ret > 0)
|
|
return ret;
|
|
if (ret == 0)
|
|
break;
|
|
dataoff += *matchoff;
|
|
}
|
|
*in_header = 0;
|
|
}
|
|
|
|
while (1) {
|
|
ret = ct_sip_get_header(ct, dptr, dataoff, datalen,
|
|
type, matchoff, matchlen);
|
|
if (ret > 0)
|
|
break;
|
|
if (ret == 0)
|
|
return ret;
|
|
dataoff += *matchoff;
|
|
}
|
|
|
|
if (in_header)
|
|
*in_header = 1;
|
|
return 1;
|
|
}
|
|
|
|
/* Locate a SIP header, parse the URI and return the offset and length of
|
|
* the address as well as the address and port themselves. A stream of
|
|
* headers can be parsed by handing in a non-NULL datalen and in_header
|
|
* pointer.
|
|
*/
|
|
int ct_sip_parse_header_uri(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int *dataoff, unsigned int datalen,
|
|
enum sip_header_types type, int *in_header,
|
|
unsigned int *matchoff, unsigned int *matchlen,
|
|
union nf_inet_addr *addr, __be16 *port)
|
|
{
|
|
const char *c, *limit = dptr + datalen;
|
|
unsigned int p;
|
|
int ret;
|
|
|
|
ret = ct_sip_walk_headers(ct, dptr, dataoff ? *dataoff : 0, datalen,
|
|
type, in_header, matchoff, matchlen);
|
|
WARN_ON(ret < 0);
|
|
if (ret == 0)
|
|
return ret;
|
|
|
|
if (!sip_parse_addr(ct, dptr + *matchoff, &c, addr, limit, true))
|
|
return -1;
|
|
if (*c == ':') {
|
|
c++;
|
|
p = simple_strtoul(c, (char **)&c, 10);
|
|
if (p < 1024 || p > 65535)
|
|
return -1;
|
|
*port = htons(p);
|
|
} else
|
|
*port = htons(SIP_PORT);
|
|
|
|
if (dataoff)
|
|
*dataoff = c - dptr;
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ct_sip_parse_header_uri);
|
|
|
|
static int ct_sip_parse_param(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
const char *name,
|
|
unsigned int *matchoff, unsigned int *matchlen)
|
|
{
|
|
const char *limit = dptr + datalen;
|
|
const char *start;
|
|
const char *end;
|
|
|
|
limit = ct_sip_header_search(dptr + dataoff, limit, ",", strlen(","));
|
|
if (!limit)
|
|
limit = dptr + datalen;
|
|
|
|
start = ct_sip_header_search(dptr + dataoff, limit, name, strlen(name));
|
|
if (!start)
|
|
return 0;
|
|
start += strlen(name);
|
|
|
|
end = ct_sip_header_search(start, limit, ";", strlen(";"));
|
|
if (!end)
|
|
end = limit;
|
|
|
|
*matchoff = start - dptr;
|
|
*matchlen = end - start;
|
|
return 1;
|
|
}
|
|
|
|
/* Parse address from header parameter and return address, offset and length */
|
|
int ct_sip_parse_address_param(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
const char *name,
|
|
unsigned int *matchoff, unsigned int *matchlen,
|
|
union nf_inet_addr *addr, bool delim)
|
|
{
|
|
const char *limit = dptr + datalen;
|
|
const char *start, *end;
|
|
|
|
limit = ct_sip_header_search(dptr + dataoff, limit, ",", strlen(","));
|
|
if (!limit)
|
|
limit = dptr + datalen;
|
|
|
|
start = ct_sip_header_search(dptr + dataoff, limit, name, strlen(name));
|
|
if (!start)
|
|
return 0;
|
|
|
|
start += strlen(name);
|
|
if (!sip_parse_addr(ct, start, &end, addr, limit, delim))
|
|
return 0;
|
|
*matchoff = start - dptr;
|
|
*matchlen = end - start;
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ct_sip_parse_address_param);
|
|
|
|
/* Parse numerical header parameter and return value, offset and length */
|
|
int ct_sip_parse_numerical_param(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
const char *name,
|
|
unsigned int *matchoff, unsigned int *matchlen,
|
|
unsigned int *val)
|
|
{
|
|
const char *limit = dptr + datalen;
|
|
const char *start;
|
|
char *end;
|
|
|
|
limit = ct_sip_header_search(dptr + dataoff, limit, ",", strlen(","));
|
|
if (!limit)
|
|
limit = dptr + datalen;
|
|
|
|
start = ct_sip_header_search(dptr + dataoff, limit, name, strlen(name));
|
|
if (!start)
|
|
return 0;
|
|
|
|
start += strlen(name);
|
|
*val = simple_strtoul(start, &end, 0);
|
|
if (start == end)
|
|
return 0;
|
|
if (matchoff && matchlen) {
|
|
*matchoff = start - dptr;
|
|
*matchlen = end - start;
|
|
}
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ct_sip_parse_numerical_param);
|
|
|
|
static int ct_sip_parse_transport(struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
u8 *proto)
|
|
{
|
|
unsigned int matchoff, matchlen;
|
|
|
|
if (ct_sip_parse_param(ct, dptr, dataoff, datalen, "transport=",
|
|
&matchoff, &matchlen)) {
|
|
if (!strnicmp(dptr + matchoff, "TCP", strlen("TCP")))
|
|
*proto = IPPROTO_TCP;
|
|
else if (!strnicmp(dptr + matchoff, "UDP", strlen("UDP")))
|
|
*proto = IPPROTO_UDP;
|
|
else
|
|
return 0;
|
|
|
|
if (*proto != nf_ct_protonum(ct))
|
|
return 0;
|
|
} else
|
|
*proto = nf_ct_protonum(ct);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int sdp_parse_addr(const struct nf_conn *ct, const char *cp,
|
|
const char **endp, union nf_inet_addr *addr,
|
|
const char *limit)
|
|
{
|
|
const char *end;
|
|
int ret;
|
|
|
|
memset(addr, 0, sizeof(*addr));
|
|
switch (nf_ct_l3num(ct)) {
|
|
case AF_INET:
|
|
ret = in4_pton(cp, limit - cp, (u8 *)&addr->ip, -1, &end);
|
|
break;
|
|
case AF_INET6:
|
|
ret = in6_pton(cp, limit - cp, (u8 *)&addr->ip6, -1, &end);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
if (ret == 0)
|
|
return 0;
|
|
if (endp)
|
|
*endp = end;
|
|
return 1;
|
|
}
|
|
|
|
/* skip ip address. returns its length. */
|
|
static int sdp_addr_len(const struct nf_conn *ct, const char *dptr,
|
|
const char *limit, int *shift)
|
|
{
|
|
union nf_inet_addr addr;
|
|
const char *aux = dptr;
|
|
|
|
if (!sdp_parse_addr(ct, dptr, &dptr, &addr, limit)) {
|
|
pr_debug("ip: %s parse failed.!\n", dptr);
|
|
return 0;
|
|
}
|
|
|
|
return dptr - aux;
|
|
}
|
|
|
|
/* SDP header parsing: a SDP session description contains an ordered set of
|
|
* headers, starting with a section containing general session parameters,
|
|
* optionally followed by multiple media descriptions.
|
|
*
|
|
* SDP headers always start at the beginning of a line. According to RFC 2327:
|
|
* "The sequence CRLF (0x0d0a) is used to end a record, although parsers should
|
|
* be tolerant and also accept records terminated with a single newline
|
|
* character". We handle both cases.
|
|
*/
|
|
static const struct sip_header ct_sdp_hdrs_v4[] = {
|
|
[SDP_HDR_VERSION] = SDP_HDR("v=", NULL, digits_len),
|
|
[SDP_HDR_OWNER] = SDP_HDR("o=", "IN IP4 ", sdp_addr_len),
|
|
[SDP_HDR_CONNECTION] = SDP_HDR("c=", "IN IP4 ", sdp_addr_len),
|
|
[SDP_HDR_MEDIA] = SDP_HDR("m=", NULL, media_len),
|
|
};
|
|
|
|
static const struct sip_header ct_sdp_hdrs_v6[] = {
|
|
[SDP_HDR_VERSION] = SDP_HDR("v=", NULL, digits_len),
|
|
[SDP_HDR_OWNER] = SDP_HDR("o=", "IN IP6 ", sdp_addr_len),
|
|
[SDP_HDR_CONNECTION] = SDP_HDR("c=", "IN IP6 ", sdp_addr_len),
|
|
[SDP_HDR_MEDIA] = SDP_HDR("m=", NULL, media_len),
|
|
};
|
|
|
|
/* Linear string search within SDP header values */
|
|
static const char *ct_sdp_header_search(const char *dptr, const char *limit,
|
|
const char *needle, unsigned int len)
|
|
{
|
|
for (limit -= len; dptr < limit; dptr++) {
|
|
if (*dptr == '\r' || *dptr == '\n')
|
|
break;
|
|
if (strncmp(dptr, needle, len) == 0)
|
|
return dptr;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Locate a SDP header (optionally a substring within the header value),
|
|
* optionally stopping at the first occurrence of the term header, parse
|
|
* it and return the offset and length of the data we're interested in.
|
|
*/
|
|
int ct_sip_get_sdp_header(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
enum sdp_header_types type,
|
|
enum sdp_header_types term,
|
|
unsigned int *matchoff, unsigned int *matchlen)
|
|
{
|
|
const struct sip_header *hdrs, *hdr, *thdr;
|
|
const char *start = dptr, *limit = dptr + datalen;
|
|
int shift = 0;
|
|
|
|
hdrs = nf_ct_l3num(ct) == NFPROTO_IPV4 ? ct_sdp_hdrs_v4 : ct_sdp_hdrs_v6;
|
|
hdr = &hdrs[type];
|
|
thdr = &hdrs[term];
|
|
|
|
for (dptr += dataoff; dptr < limit; dptr++) {
|
|
/* Find beginning of line */
|
|
if (*dptr != '\r' && *dptr != '\n')
|
|
continue;
|
|
if (++dptr >= limit)
|
|
break;
|
|
if (*(dptr - 1) == '\r' && *dptr == '\n') {
|
|
if (++dptr >= limit)
|
|
break;
|
|
}
|
|
|
|
if (term != SDP_HDR_UNSPEC &&
|
|
limit - dptr >= thdr->len &&
|
|
strnicmp(dptr, thdr->name, thdr->len) == 0)
|
|
break;
|
|
else if (limit - dptr >= hdr->len &&
|
|
strnicmp(dptr, hdr->name, hdr->len) == 0)
|
|
dptr += hdr->len;
|
|
else
|
|
continue;
|
|
|
|
*matchoff = dptr - start;
|
|
if (hdr->search) {
|
|
dptr = ct_sdp_header_search(dptr, limit, hdr->search,
|
|
hdr->slen);
|
|
if (!dptr)
|
|
return -1;
|
|
dptr += hdr->slen;
|
|
}
|
|
|
|
*matchlen = hdr->match_len(ct, dptr, limit, &shift);
|
|
if (!*matchlen)
|
|
return -1;
|
|
*matchoff = dptr - start + shift;
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ct_sip_get_sdp_header);
|
|
|
|
static int ct_sip_parse_sdp_addr(const struct nf_conn *ct, const char *dptr,
|
|
unsigned int dataoff, unsigned int datalen,
|
|
enum sdp_header_types type,
|
|
enum sdp_header_types term,
|
|
unsigned int *matchoff, unsigned int *matchlen,
|
|
union nf_inet_addr *addr)
|
|
{
|
|
int ret;
|
|
|
|
ret = ct_sip_get_sdp_header(ct, dptr, dataoff, datalen, type, term,
|
|
matchoff, matchlen);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
if (!sdp_parse_addr(ct, dptr + *matchoff, NULL, addr,
|
|
dptr + *matchoff + *matchlen))
|
|
return -1;
|
|
return 1;
|
|
}
|
|
|
|
static int refresh_signalling_expectation(struct nf_conn *ct,
|
|
union nf_inet_addr *addr,
|
|
u8 proto, __be16 port,
|
|
unsigned int expires)
|
|
{
|
|
struct nf_conn_help *help = nfct_help(ct);
|
|
struct nf_conntrack_expect *exp;
|
|
struct hlist_node *next;
|
|
int found = 0;
|
|
|
|
spin_lock_bh(&nf_conntrack_lock);
|
|
hlist_for_each_entry_safe(exp, next, &help->expectations, lnode) {
|
|
if (exp->class != SIP_EXPECT_SIGNALLING ||
|
|
!nf_inet_addr_cmp(&exp->tuple.dst.u3, addr) ||
|
|
exp->tuple.dst.protonum != proto ||
|
|
exp->tuple.dst.u.udp.port != port)
|
|
continue;
|
|
if (!del_timer(&exp->timeout))
|
|
continue;
|
|
exp->flags &= ~NF_CT_EXPECT_INACTIVE;
|
|
exp->timeout.expires = jiffies + expires * HZ;
|
|
add_timer(&exp->timeout);
|
|
found = 1;
|
|
break;
|
|
}
|
|
spin_unlock_bh(&nf_conntrack_lock);
|
|
return found;
|
|
}
|
|
|
|
static void flush_expectations(struct nf_conn *ct, bool media)
|
|
{
|
|
struct nf_conn_help *help = nfct_help(ct);
|
|
struct nf_conntrack_expect *exp;
|
|
struct hlist_node *next;
|
|
|
|
spin_lock_bh(&nf_conntrack_lock);
|
|
hlist_for_each_entry_safe(exp, next, &help->expectations, lnode) {
|
|
if ((exp->class != SIP_EXPECT_SIGNALLING) ^ media)
|
|
continue;
|
|
if (!del_timer(&exp->timeout))
|
|
continue;
|
|
nf_ct_unlink_expect(exp);
|
|
nf_ct_expect_put(exp);
|
|
if (!media)
|
|
break;
|
|
}
|
|
spin_unlock_bh(&nf_conntrack_lock);
|
|
}
|
|
|
|
static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
union nf_inet_addr *daddr, __be16 port,
|
|
enum sip_expectation_classes class,
|
|
unsigned int mediaoff, unsigned int medialen)
|
|
{
|
|
struct nf_conntrack_expect *exp, *rtp_exp, *rtcp_exp;
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct net *net = nf_ct_net(ct);
|
|
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
union nf_inet_addr *saddr;
|
|
struct nf_conntrack_tuple tuple;
|
|
int direct_rtp = 0, skip_expect = 0, ret = NF_DROP;
|
|
u_int16_t base_port;
|
|
__be16 rtp_port, rtcp_port;
|
|
typeof(nf_nat_sdp_port_hook) nf_nat_sdp_port;
|
|
typeof(nf_nat_sdp_media_hook) nf_nat_sdp_media;
|
|
|
|
saddr = NULL;
|
|
if (sip_direct_media) {
|
|
if (!nf_inet_addr_cmp(daddr, &ct->tuplehash[dir].tuple.src.u3))
|
|
return NF_ACCEPT;
|
|
saddr = &ct->tuplehash[!dir].tuple.src.u3;
|
|
}
|
|
|
|
/* We need to check whether the registration exists before attempting
|
|
* to register it since we can see the same media description multiple
|
|
* times on different connections in case multiple endpoints receive
|
|
* the same call.
|
|
*
|
|
* RTP optimization: if we find a matching media channel expectation
|
|
* and both the expectation and this connection are SNATed, we assume
|
|
* both sides can reach each other directly and use the final
|
|
* destination address from the expectation. We still need to keep
|
|
* the NATed expectations for media that might arrive from the
|
|
* outside, and additionally need to expect the direct RTP stream
|
|
* in case it passes through us even without NAT.
|
|
*/
|
|
memset(&tuple, 0, sizeof(tuple));
|
|
if (saddr)
|
|
tuple.src.u3 = *saddr;
|
|
tuple.src.l3num = nf_ct_l3num(ct);
|
|
tuple.dst.protonum = IPPROTO_UDP;
|
|
tuple.dst.u3 = *daddr;
|
|
tuple.dst.u.udp.port = port;
|
|
|
|
rcu_read_lock();
|
|
do {
|
|
exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
|
|
|
|
if (!exp || exp->master == ct ||
|
|
nfct_help(exp->master)->helper != nfct_help(ct)->helper ||
|
|
exp->class != class)
|
|
break;
|
|
#ifdef CONFIG_NF_NAT_NEEDED
|
|
if (!direct_rtp &&
|
|
(!nf_inet_addr_cmp(&exp->saved_addr, &exp->tuple.dst.u3) ||
|
|
exp->saved_proto.udp.port != exp->tuple.dst.u.udp.port) &&
|
|
ct->status & IPS_NAT_MASK) {
|
|
*daddr = exp->saved_addr;
|
|
tuple.dst.u3 = exp->saved_addr;
|
|
tuple.dst.u.udp.port = exp->saved_proto.udp.port;
|
|
direct_rtp = 1;
|
|
} else
|
|
#endif
|
|
skip_expect = 1;
|
|
} while (!skip_expect);
|
|
rcu_read_unlock();
|
|
|
|
base_port = ntohs(tuple.dst.u.udp.port) & ~1;
|
|
rtp_port = htons(base_port);
|
|
rtcp_port = htons(base_port + 1);
|
|
|
|
if (direct_rtp) {
|
|
nf_nat_sdp_port = rcu_dereference(nf_nat_sdp_port_hook);
|
|
if (nf_nat_sdp_port &&
|
|
!nf_nat_sdp_port(skb, protoff, dataoff, dptr, datalen,
|
|
mediaoff, medialen, ntohs(rtp_port)))
|
|
goto err1;
|
|
}
|
|
|
|
if (skip_expect)
|
|
return NF_ACCEPT;
|
|
|
|
rtp_exp = nf_ct_expect_alloc(ct);
|
|
if (rtp_exp == NULL)
|
|
goto err1;
|
|
nf_ct_expect_init(rtp_exp, class, nf_ct_l3num(ct), saddr, daddr,
|
|
IPPROTO_UDP, NULL, &rtp_port);
|
|
|
|
rtcp_exp = nf_ct_expect_alloc(ct);
|
|
if (rtcp_exp == NULL)
|
|
goto err2;
|
|
nf_ct_expect_init(rtcp_exp, class, nf_ct_l3num(ct), saddr, daddr,
|
|
IPPROTO_UDP, NULL, &rtcp_port);
|
|
|
|
nf_nat_sdp_media = rcu_dereference(nf_nat_sdp_media_hook);
|
|
if (nf_nat_sdp_media && ct->status & IPS_NAT_MASK && !direct_rtp)
|
|
ret = nf_nat_sdp_media(skb, protoff, dataoff, dptr, datalen,
|
|
rtp_exp, rtcp_exp,
|
|
mediaoff, medialen, daddr);
|
|
else {
|
|
if (nf_ct_expect_related(rtp_exp) == 0) {
|
|
if (nf_ct_expect_related(rtcp_exp) != 0)
|
|
nf_ct_unexpect_related(rtp_exp);
|
|
else
|
|
ret = NF_ACCEPT;
|
|
}
|
|
}
|
|
nf_ct_expect_put(rtcp_exp);
|
|
err2:
|
|
nf_ct_expect_put(rtp_exp);
|
|
err1:
|
|
return ret;
|
|
}
|
|
|
|
static const struct sdp_media_type sdp_media_types[] = {
|
|
SDP_MEDIA_TYPE("audio ", SIP_EXPECT_AUDIO),
|
|
SDP_MEDIA_TYPE("video ", SIP_EXPECT_VIDEO),
|
|
SDP_MEDIA_TYPE("image ", SIP_EXPECT_IMAGE),
|
|
};
|
|
|
|
static const struct sdp_media_type *sdp_media_type(const char *dptr,
|
|
unsigned int matchoff,
|
|
unsigned int matchlen)
|
|
{
|
|
const struct sdp_media_type *t;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(sdp_media_types); i++) {
|
|
t = &sdp_media_types[i];
|
|
if (matchlen < t->len ||
|
|
strncmp(dptr + matchoff, t->name, t->len))
|
|
continue;
|
|
return t;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int process_sdp(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
unsigned int matchoff, matchlen;
|
|
unsigned int mediaoff, medialen;
|
|
unsigned int sdpoff;
|
|
unsigned int caddr_len, maddr_len;
|
|
unsigned int i;
|
|
union nf_inet_addr caddr, maddr, rtp_addr;
|
|
unsigned int port;
|
|
const struct sdp_media_type *t;
|
|
int ret = NF_ACCEPT;
|
|
typeof(nf_nat_sdp_addr_hook) nf_nat_sdp_addr;
|
|
typeof(nf_nat_sdp_session_hook) nf_nat_sdp_session;
|
|
|
|
nf_nat_sdp_addr = rcu_dereference(nf_nat_sdp_addr_hook);
|
|
|
|
/* Find beginning of session description */
|
|
if (ct_sip_get_sdp_header(ct, *dptr, 0, *datalen,
|
|
SDP_HDR_VERSION, SDP_HDR_UNSPEC,
|
|
&matchoff, &matchlen) <= 0)
|
|
return NF_ACCEPT;
|
|
sdpoff = matchoff;
|
|
|
|
/* The connection information is contained in the session description
|
|
* and/or once per media description. The first media description marks
|
|
* the end of the session description. */
|
|
caddr_len = 0;
|
|
if (ct_sip_parse_sdp_addr(ct, *dptr, sdpoff, *datalen,
|
|
SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
|
|
&matchoff, &matchlen, &caddr) > 0)
|
|
caddr_len = matchlen;
|
|
|
|
mediaoff = sdpoff;
|
|
for (i = 0; i < ARRAY_SIZE(sdp_media_types); ) {
|
|
if (ct_sip_get_sdp_header(ct, *dptr, mediaoff, *datalen,
|
|
SDP_HDR_MEDIA, SDP_HDR_UNSPEC,
|
|
&mediaoff, &medialen) <= 0)
|
|
break;
|
|
|
|
/* Get media type and port number. A media port value of zero
|
|
* indicates an inactive stream. */
|
|
t = sdp_media_type(*dptr, mediaoff, medialen);
|
|
if (!t) {
|
|
mediaoff += medialen;
|
|
continue;
|
|
}
|
|
mediaoff += t->len;
|
|
medialen -= t->len;
|
|
|
|
port = simple_strtoul(*dptr + mediaoff, NULL, 10);
|
|
if (port == 0)
|
|
continue;
|
|
if (port < 1024 || port > 65535) {
|
|
nf_ct_helper_log(skb, ct, "wrong port %u", port);
|
|
return NF_DROP;
|
|
}
|
|
|
|
/* The media description overrides the session description. */
|
|
maddr_len = 0;
|
|
if (ct_sip_parse_sdp_addr(ct, *dptr, mediaoff, *datalen,
|
|
SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
|
|
&matchoff, &matchlen, &maddr) > 0) {
|
|
maddr_len = matchlen;
|
|
memcpy(&rtp_addr, &maddr, sizeof(rtp_addr));
|
|
} else if (caddr_len)
|
|
memcpy(&rtp_addr, &caddr, sizeof(rtp_addr));
|
|
else {
|
|
nf_ct_helper_log(skb, ct, "cannot parse SDP message");
|
|
return NF_DROP;
|
|
}
|
|
|
|
ret = set_expected_rtp_rtcp(skb, protoff, dataoff,
|
|
dptr, datalen,
|
|
&rtp_addr, htons(port), t->class,
|
|
mediaoff, medialen);
|
|
if (ret != NF_ACCEPT) {
|
|
nf_ct_helper_log(skb, ct,
|
|
"cannot add expectation for voice");
|
|
return ret;
|
|
}
|
|
|
|
/* Update media connection address if present */
|
|
if (maddr_len && nf_nat_sdp_addr && ct->status & IPS_NAT_MASK) {
|
|
ret = nf_nat_sdp_addr(skb, protoff, dataoff,
|
|
dptr, datalen, mediaoff,
|
|
SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
|
|
&rtp_addr);
|
|
if (ret != NF_ACCEPT) {
|
|
nf_ct_helper_log(skb, ct, "cannot mangle SDP");
|
|
return ret;
|
|
}
|
|
}
|
|
i++;
|
|
}
|
|
|
|
/* Update session connection and owner addresses */
|
|
nf_nat_sdp_session = rcu_dereference(nf_nat_sdp_session_hook);
|
|
if (nf_nat_sdp_session && ct->status & IPS_NAT_MASK)
|
|
ret = nf_nat_sdp_session(skb, protoff, dataoff,
|
|
dptr, datalen, sdpoff, &rtp_addr);
|
|
|
|
return ret;
|
|
}
|
|
static int process_invite_response(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq, unsigned int code)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
|
|
if ((code >= 100 && code <= 199) ||
|
|
(code >= 200 && code <= 299))
|
|
return process_sdp(skb, protoff, dataoff, dptr, datalen, cseq);
|
|
else if (ct_sip_info->invite_cseq == cseq)
|
|
flush_expectations(ct, true);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static int process_update_response(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq, unsigned int code)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
|
|
if ((code >= 100 && code <= 199) ||
|
|
(code >= 200 && code <= 299))
|
|
return process_sdp(skb, protoff, dataoff, dptr, datalen, cseq);
|
|
else if (ct_sip_info->invite_cseq == cseq)
|
|
flush_expectations(ct, true);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static int process_prack_response(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq, unsigned int code)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
|
|
if ((code >= 100 && code <= 199) ||
|
|
(code >= 200 && code <= 299))
|
|
return process_sdp(skb, protoff, dataoff, dptr, datalen, cseq);
|
|
else if (ct_sip_info->invite_cseq == cseq)
|
|
flush_expectations(ct, true);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static int process_invite_request(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
unsigned int ret;
|
|
|
|
flush_expectations(ct, true);
|
|
ret = process_sdp(skb, protoff, dataoff, dptr, datalen, cseq);
|
|
if (ret == NF_ACCEPT)
|
|
ct_sip_info->invite_cseq = cseq;
|
|
return ret;
|
|
}
|
|
|
|
static int process_bye_request(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
|
|
flush_expectations(ct, true);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
/* Parse a REGISTER request and create a permanent expectation for incoming
|
|
* signalling connections. The expectation is marked inactive and is activated
|
|
* when receiving a response indicating success from the registrar.
|
|
*/
|
|
static int process_register_request(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
unsigned int matchoff, matchlen;
|
|
struct nf_conntrack_expect *exp;
|
|
union nf_inet_addr *saddr, daddr;
|
|
__be16 port;
|
|
u8 proto;
|
|
unsigned int expires = 0;
|
|
int ret;
|
|
typeof(nf_nat_sip_expect_hook) nf_nat_sip_expect;
|
|
|
|
/* Expected connections can not register again. */
|
|
if (ct->status & IPS_EXPECTED)
|
|
return NF_ACCEPT;
|
|
|
|
/* We must check the expiration time: a value of zero signals the
|
|
* registrar to release the binding. We'll remove our expectation
|
|
* when receiving the new bindings in the response, but we don't
|
|
* want to create new ones.
|
|
*
|
|
* The expiration time may be contained in Expires: header, the
|
|
* Contact: header parameters or the URI parameters.
|
|
*/
|
|
if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_EXPIRES,
|
|
&matchoff, &matchlen) > 0)
|
|
expires = simple_strtoul(*dptr + matchoff, NULL, 10);
|
|
|
|
ret = ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen,
|
|
SIP_HDR_CONTACT, NULL,
|
|
&matchoff, &matchlen, &daddr, &port);
|
|
if (ret < 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse contact");
|
|
return NF_DROP;
|
|
} else if (ret == 0)
|
|
return NF_ACCEPT;
|
|
|
|
/* We don't support third-party registrations */
|
|
if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3, &daddr))
|
|
return NF_ACCEPT;
|
|
|
|
if (ct_sip_parse_transport(ct, *dptr, matchoff + matchlen, *datalen,
|
|
&proto) == 0)
|
|
return NF_ACCEPT;
|
|
|
|
if (ct_sip_parse_numerical_param(ct, *dptr,
|
|
matchoff + matchlen, *datalen,
|
|
"expires=", NULL, NULL, &expires) < 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse expires");
|
|
return NF_DROP;
|
|
}
|
|
|
|
if (expires == 0) {
|
|
ret = NF_ACCEPT;
|
|
goto store_cseq;
|
|
}
|
|
|
|
exp = nf_ct_expect_alloc(ct);
|
|
if (!exp) {
|
|
nf_ct_helper_log(skb, ct, "cannot alloc expectation");
|
|
return NF_DROP;
|
|
}
|
|
|
|
saddr = NULL;
|
|
if (sip_direct_signalling)
|
|
saddr = &ct->tuplehash[!dir].tuple.src.u3;
|
|
|
|
nf_ct_expect_init(exp, SIP_EXPECT_SIGNALLING, nf_ct_l3num(ct),
|
|
saddr, &daddr, proto, NULL, &port);
|
|
exp->timeout.expires = sip_timeout * HZ;
|
|
exp->helper = nfct_help(ct)->helper;
|
|
exp->flags = NF_CT_EXPECT_PERMANENT | NF_CT_EXPECT_INACTIVE;
|
|
|
|
nf_nat_sip_expect = rcu_dereference(nf_nat_sip_expect_hook);
|
|
if (nf_nat_sip_expect && ct->status & IPS_NAT_MASK)
|
|
ret = nf_nat_sip_expect(skb, protoff, dataoff, dptr, datalen,
|
|
exp, matchoff, matchlen);
|
|
else {
|
|
if (nf_ct_expect_related(exp) != 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot add expectation");
|
|
ret = NF_DROP;
|
|
} else
|
|
ret = NF_ACCEPT;
|
|
}
|
|
nf_ct_expect_put(exp);
|
|
|
|
store_cseq:
|
|
if (ret == NF_ACCEPT)
|
|
ct_sip_info->register_cseq = cseq;
|
|
return ret;
|
|
}
|
|
|
|
static int process_register_response(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen,
|
|
unsigned int cseq, unsigned int code)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
union nf_inet_addr addr;
|
|
__be16 port;
|
|
u8 proto;
|
|
unsigned int matchoff, matchlen, coff = 0;
|
|
unsigned int expires = 0;
|
|
int in_contact = 0, ret;
|
|
|
|
/* According to RFC 3261, "UAs MUST NOT send a new registration until
|
|
* they have received a final response from the registrar for the
|
|
* previous one or the previous REGISTER request has timed out".
|
|
*
|
|
* However, some servers fail to detect retransmissions and send late
|
|
* responses, so we store the sequence number of the last valid
|
|
* request and compare it here.
|
|
*/
|
|
if (ct_sip_info->register_cseq != cseq)
|
|
return NF_ACCEPT;
|
|
|
|
if (code >= 100 && code <= 199)
|
|
return NF_ACCEPT;
|
|
if (code < 200 || code > 299)
|
|
goto flush;
|
|
|
|
if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_EXPIRES,
|
|
&matchoff, &matchlen) > 0)
|
|
expires = simple_strtoul(*dptr + matchoff, NULL, 10);
|
|
|
|
while (1) {
|
|
unsigned int c_expires = expires;
|
|
|
|
ret = ct_sip_parse_header_uri(ct, *dptr, &coff, *datalen,
|
|
SIP_HDR_CONTACT, &in_contact,
|
|
&matchoff, &matchlen,
|
|
&addr, &port);
|
|
if (ret < 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse contact");
|
|
return NF_DROP;
|
|
} else if (ret == 0)
|
|
break;
|
|
|
|
/* We don't support third-party registrations */
|
|
if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, &addr))
|
|
continue;
|
|
|
|
if (ct_sip_parse_transport(ct, *dptr, matchoff + matchlen,
|
|
*datalen, &proto) == 0)
|
|
continue;
|
|
|
|
ret = ct_sip_parse_numerical_param(ct, *dptr,
|
|
matchoff + matchlen,
|
|
*datalen, "expires=",
|
|
NULL, NULL, &c_expires);
|
|
if (ret < 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse expires");
|
|
return NF_DROP;
|
|
}
|
|
if (c_expires == 0)
|
|
break;
|
|
if (refresh_signalling_expectation(ct, &addr, proto, port,
|
|
c_expires))
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
flush:
|
|
flush_expectations(ct, false);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static const struct sip_handler sip_handlers[] = {
|
|
SIP_HANDLER("INVITE", process_invite_request, process_invite_response),
|
|
SIP_HANDLER("UPDATE", process_sdp, process_update_response),
|
|
SIP_HANDLER("ACK", process_sdp, NULL),
|
|
SIP_HANDLER("PRACK", process_sdp, process_prack_response),
|
|
SIP_HANDLER("BYE", process_bye_request, NULL),
|
|
SIP_HANDLER("REGISTER", process_register_request, process_register_response),
|
|
};
|
|
|
|
static int process_sip_response(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
unsigned int matchoff, matchlen, matchend;
|
|
unsigned int code, cseq, i;
|
|
|
|
if (*datalen < strlen("SIP/2.0 200"))
|
|
return NF_ACCEPT;
|
|
code = simple_strtoul(*dptr + strlen("SIP/2.0 "), NULL, 10);
|
|
if (!code) {
|
|
nf_ct_helper_log(skb, ct, "cannot get code");
|
|
return NF_DROP;
|
|
}
|
|
|
|
if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_CSEQ,
|
|
&matchoff, &matchlen) <= 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse cseq");
|
|
return NF_DROP;
|
|
}
|
|
cseq = simple_strtoul(*dptr + matchoff, NULL, 10);
|
|
if (!cseq) {
|
|
nf_ct_helper_log(skb, ct, "cannot get cseq");
|
|
return NF_DROP;
|
|
}
|
|
matchend = matchoff + matchlen + 1;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
|
|
const struct sip_handler *handler;
|
|
|
|
handler = &sip_handlers[i];
|
|
if (handler->response == NULL)
|
|
continue;
|
|
if (*datalen < matchend + handler->len ||
|
|
strnicmp(*dptr + matchend, handler->method, handler->len))
|
|
continue;
|
|
return handler->response(skb, protoff, dataoff, dptr, datalen,
|
|
cseq, code);
|
|
}
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static int process_sip_request(struct sk_buff *skb, unsigned int protoff,
|
|
unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen)
|
|
{
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
|
|
struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
|
|
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
unsigned int matchoff, matchlen;
|
|
unsigned int cseq, i;
|
|
union nf_inet_addr addr;
|
|
__be16 port;
|
|
|
|
/* Many Cisco IP phones use a high source port for SIP requests, but
|
|
* listen for the response on port 5060. If we are the local
|
|
* router for one of these phones, save the port number from the
|
|
* Via: header so that nf_nat_sip can redirect the responses to
|
|
* the correct port.
|
|
*/
|
|
if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen,
|
|
SIP_HDR_VIA_UDP, NULL, &matchoff,
|
|
&matchlen, &addr, &port) > 0 &&
|
|
port != ct->tuplehash[dir].tuple.src.u.udp.port &&
|
|
nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.src.u3))
|
|
ct_sip_info->forced_dport = port;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
|
|
const struct sip_handler *handler;
|
|
|
|
handler = &sip_handlers[i];
|
|
if (handler->request == NULL)
|
|
continue;
|
|
if (*datalen < handler->len ||
|
|
strnicmp(*dptr, handler->method, handler->len))
|
|
continue;
|
|
|
|
if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_CSEQ,
|
|
&matchoff, &matchlen) <= 0) {
|
|
nf_ct_helper_log(skb, ct, "cannot parse cseq");
|
|
return NF_DROP;
|
|
}
|
|
cseq = simple_strtoul(*dptr + matchoff, NULL, 10);
|
|
if (!cseq) {
|
|
nf_ct_helper_log(skb, ct, "cannot get cseq");
|
|
return NF_DROP;
|
|
}
|
|
|
|
return handler->request(skb, protoff, dataoff, dptr, datalen,
|
|
cseq);
|
|
}
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static int process_sip_msg(struct sk_buff *skb, struct nf_conn *ct,
|
|
unsigned int protoff, unsigned int dataoff,
|
|
const char **dptr, unsigned int *datalen)
|
|
{
|
|
typeof(nf_nat_sip_hook) nf_nat_sip;
|
|
int ret;
|
|
|
|
if (strnicmp(*dptr, "SIP/2.0 ", strlen("SIP/2.0 ")) != 0)
|
|
ret = process_sip_request(skb, protoff, dataoff, dptr, datalen);
|
|
else
|
|
ret = process_sip_response(skb, protoff, dataoff, dptr, datalen);
|
|
|
|
if (ret == NF_ACCEPT && ct->status & IPS_NAT_MASK) {
|
|
nf_nat_sip = rcu_dereference(nf_nat_sip_hook);
|
|
if (nf_nat_sip && !nf_nat_sip(skb, protoff, dataoff,
|
|
dptr, datalen)) {
|
|
nf_ct_helper_log(skb, ct, "cannot NAT SIP message");
|
|
ret = NF_DROP;
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff,
|
|
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
|
|
{
|
|
struct tcphdr *th, _tcph;
|
|
unsigned int dataoff, datalen;
|
|
unsigned int matchoff, matchlen, clen;
|
|
unsigned int msglen, origlen;
|
|
const char *dptr, *end;
|
|
s16 diff, tdiff = 0;
|
|
int ret = NF_ACCEPT;
|
|
bool term;
|
|
typeof(nf_nat_sip_seq_adjust_hook) nf_nat_sip_seq_adjust;
|
|
|
|
if (ctinfo != IP_CT_ESTABLISHED &&
|
|
ctinfo != IP_CT_ESTABLISHED_REPLY)
|
|
return NF_ACCEPT;
|
|
|
|
/* No Data ? */
|
|
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
|
|
if (th == NULL)
|
|
return NF_ACCEPT;
|
|
dataoff = protoff + th->doff * 4;
|
|
if (dataoff >= skb->len)
|
|
return NF_ACCEPT;
|
|
|
|
nf_ct_refresh(ct, skb, sip_timeout * HZ);
|
|
|
|
if (unlikely(skb_linearize(skb)))
|
|
return NF_DROP;
|
|
|
|
dptr = skb->data + dataoff;
|
|
datalen = skb->len - dataoff;
|
|
if (datalen < strlen("SIP/2.0 200"))
|
|
return NF_ACCEPT;
|
|
|
|
while (1) {
|
|
if (ct_sip_get_header(ct, dptr, 0, datalen,
|
|
SIP_HDR_CONTENT_LENGTH,
|
|
&matchoff, &matchlen) <= 0)
|
|
break;
|
|
|
|
clen = simple_strtoul(dptr + matchoff, (char **)&end, 10);
|
|
if (dptr + matchoff == end)
|
|
break;
|
|
|
|
term = false;
|
|
for (; end + strlen("\r\n\r\n") <= dptr + datalen; end++) {
|
|
if (end[0] == '\r' && end[1] == '\n' &&
|
|
end[2] == '\r' && end[3] == '\n') {
|
|
term = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!term)
|
|
break;
|
|
end += strlen("\r\n\r\n") + clen;
|
|
|
|
msglen = origlen = end - dptr;
|
|
if (msglen > datalen) {
|
|
nf_ct_helper_log(skb, ct, "incomplete/bad SIP message");
|
|
return NF_DROP;
|
|
}
|
|
|
|
ret = process_sip_msg(skb, ct, protoff, dataoff,
|
|
&dptr, &msglen);
|
|
/* process_sip_* functions report why this packet is dropped */
|
|
if (ret != NF_ACCEPT)
|
|
break;
|
|
diff = msglen - origlen;
|
|
tdiff += diff;
|
|
|
|
dataoff += msglen;
|
|
dptr += msglen;
|
|
datalen = datalen + diff - msglen;
|
|
}
|
|
|
|
if (ret == NF_ACCEPT && ct->status & IPS_NAT_MASK) {
|
|
nf_nat_sip_seq_adjust = rcu_dereference(nf_nat_sip_seq_adjust_hook);
|
|
if (nf_nat_sip_seq_adjust)
|
|
nf_nat_sip_seq_adjust(skb, protoff, tdiff);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int sip_help_udp(struct sk_buff *skb, unsigned int protoff,
|
|
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
|
|
{
|
|
unsigned int dataoff, datalen;
|
|
const char *dptr;
|
|
|
|
/* No Data ? */
|
|
dataoff = protoff + sizeof(struct udphdr);
|
|
if (dataoff >= skb->len)
|
|
return NF_ACCEPT;
|
|
|
|
nf_ct_refresh(ct, skb, sip_timeout * HZ);
|
|
|
|
if (unlikely(skb_linearize(skb)))
|
|
return NF_DROP;
|
|
|
|
dptr = skb->data + dataoff;
|
|
datalen = skb->len - dataoff;
|
|
if (datalen < strlen("SIP/2.0 200"))
|
|
return NF_ACCEPT;
|
|
|
|
return process_sip_msg(skb, ct, protoff, dataoff, &dptr, &datalen);
|
|
}
|
|
|
|
static struct nf_conntrack_helper sip[MAX_PORTS][4] __read_mostly;
|
|
|
|
static const struct nf_conntrack_expect_policy sip_exp_policy[SIP_EXPECT_MAX + 1] = {
|
|
[SIP_EXPECT_SIGNALLING] = {
|
|
.name = "signalling",
|
|
.max_expected = 1,
|
|
.timeout = 3 * 60,
|
|
},
|
|
[SIP_EXPECT_AUDIO] = {
|
|
.name = "audio",
|
|
.max_expected = 2 * IP_CT_DIR_MAX,
|
|
.timeout = 3 * 60,
|
|
},
|
|
[SIP_EXPECT_VIDEO] = {
|
|
.name = "video",
|
|
.max_expected = 2 * IP_CT_DIR_MAX,
|
|
.timeout = 3 * 60,
|
|
},
|
|
[SIP_EXPECT_IMAGE] = {
|
|
.name = "image",
|
|
.max_expected = IP_CT_DIR_MAX,
|
|
.timeout = 3 * 60,
|
|
},
|
|
};
|
|
|
|
static void nf_conntrack_sip_fini(void)
|
|
{
|
|
int i, j;
|
|
|
|
for (i = 0; i < ports_c; i++) {
|
|
for (j = 0; j < ARRAY_SIZE(sip[i]); j++) {
|
|
if (sip[i][j].me == NULL)
|
|
continue;
|
|
nf_conntrack_helper_unregister(&sip[i][j]);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __init nf_conntrack_sip_init(void)
|
|
{
|
|
int i, j, ret;
|
|
|
|
if (ports_c == 0)
|
|
ports[ports_c++] = SIP_PORT;
|
|
|
|
for (i = 0; i < ports_c; i++) {
|
|
memset(&sip[i], 0, sizeof(sip[i]));
|
|
|
|
sip[i][0].tuple.src.l3num = AF_INET;
|
|
sip[i][0].tuple.dst.protonum = IPPROTO_UDP;
|
|
sip[i][0].help = sip_help_udp;
|
|
sip[i][1].tuple.src.l3num = AF_INET;
|
|
sip[i][1].tuple.dst.protonum = IPPROTO_TCP;
|
|
sip[i][1].help = sip_help_tcp;
|
|
|
|
sip[i][2].tuple.src.l3num = AF_INET6;
|
|
sip[i][2].tuple.dst.protonum = IPPROTO_UDP;
|
|
sip[i][2].help = sip_help_udp;
|
|
sip[i][3].tuple.src.l3num = AF_INET6;
|
|
sip[i][3].tuple.dst.protonum = IPPROTO_TCP;
|
|
sip[i][3].help = sip_help_tcp;
|
|
|
|
for (j = 0; j < ARRAY_SIZE(sip[i]); j++) {
|
|
sip[i][j].data_len = sizeof(struct nf_ct_sip_master);
|
|
sip[i][j].tuple.src.u.udp.port = htons(ports[i]);
|
|
sip[i][j].expect_policy = sip_exp_policy;
|
|
sip[i][j].expect_class_max = SIP_EXPECT_MAX;
|
|
sip[i][j].me = THIS_MODULE;
|
|
|
|
if (ports[i] == SIP_PORT)
|
|
sprintf(sip[i][j].name, "sip");
|
|
else
|
|
sprintf(sip[i][j].name, "sip-%u", i);
|
|
|
|
pr_debug("port #%u: %u\n", i, ports[i]);
|
|
|
|
ret = nf_conntrack_helper_register(&sip[i][j]);
|
|
if (ret) {
|
|
printk(KERN_ERR "nf_ct_sip: failed to register"
|
|
" helper for pf: %u port: %u\n",
|
|
sip[i][j].tuple.src.l3num, ports[i]);
|
|
nf_conntrack_sip_fini();
|
|
return ret;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
module_init(nf_conntrack_sip_init);
|
|
module_exit(nf_conntrack_sip_fini);
|