1 #define KMSG_COMPONENT "IPVS"
2 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
4 #include <linux/module.h>
5 #include <linux/kernel.h>
8 #include <net/netfilter/nf_conntrack.h>
9 #include <linux/netfilter/nf_conntrack_sip.h>
11 #ifdef CONFIG_IP_VS_DEBUG
12 static const char *ip_vs_dbg_callid(char *buf, size_t buf_len,
13 const char *callid, size_t callid_len,
17 size_t len = min3(max_len, callid_len, buf_len - *idx - 1);
18 memcpy(buf + *idx, callid, len);
21 return buf + *idx - len;
24 #define IP_VS_DEBUG_CALLID(callid, len) \
25 ip_vs_dbg_callid(ip_vs_dbg_buf, sizeof(ip_vs_dbg_buf), \
26 callid, len, &ip_vs_dbg_idx)
29 static int get_callid(const char *dptr, unsigned int dataoff,
31 unsigned int *matchoff, unsigned int *matchlen)
35 int ret = ct_sip_get_header(NULL, dptr, dataoff, datalen,
36 SIP_HDR_CALL_ID, matchoff,
45 /* Empty callid is useless */
49 /* Too large is useless */
50 if (*matchlen > IP_VS_PEDATA_MAXLEN)
53 /* SIP headers are always followed by a line terminator */
54 if (*matchoff + *matchlen == datalen)
57 /* RFC 2543 allows lines to be terminated with CR, LF or CRLF,
58 * RFC 3261 allows only CRLF, we support both. */
59 if (*(dptr + *matchoff + *matchlen) != '\r' &&
60 *(dptr + *matchoff + *matchlen) != '\n')
63 IP_VS_DBG_BUF(9, "SIP callid %s (%d bytes)\n",
64 IP_VS_DEBUG_CALLID(dptr + *matchoff, *matchlen),
70 ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
72 struct sk_buff *reasm = skb_nfct_reasm(skb);
73 struct ip_vs_iphdr iph;
74 unsigned int dataoff, datalen, matchoff, matchlen;
78 ip_vs_fill_iph_skb(p->af, skb, &iph);
80 /* Only useful with UDP */
81 if (iph.protocol != IPPROTO_UDP)
83 /* todo: IPv6 fragments:
84 * I think this only should be done for the first fragment. /HS
88 dataoff = iph.thoff_reasm + sizeof(struct udphdr);
90 dataoff = iph.len + sizeof(struct udphdr);
92 if (dataoff >= skb->len)
94 /* todo: Check if this will mess-up the reasm skb !!! /HS */
95 retc = skb_linearize(skb);
98 dptr = skb->data + dataoff;
99 datalen = skb->len - dataoff;
101 if (get_callid(dptr, dataoff, datalen, &matchoff, &matchlen))
104 /* N.B: pe_data is only set on success,
105 * this allows fallback to the default persistence logic on failure
107 p->pe_data = kmemdup(dptr + matchoff, matchlen, GFP_ATOMIC);
111 p->pe_data_len = matchlen;
116 static bool ip_vs_sip_ct_match(const struct ip_vs_conn_param *p,
117 struct ip_vs_conn *ct)
122 if (ct->af == p->af &&
123 ip_vs_addr_equal(p->af, p->caddr, &ct->caddr) &&
124 /* protocol should only be IPPROTO_IP if
125 * d_addr is a fwmark */
126 ip_vs_addr_equal(p->protocol == IPPROTO_IP ? AF_UNSPEC : p->af,
127 p->vaddr, &ct->vaddr) &&
128 ct->vport == p->vport &&
129 ct->flags & IP_VS_CONN_F_TEMPLATE &&
130 ct->protocol == p->protocol &&
131 ct->pe_data && ct->pe_data_len == p->pe_data_len &&
132 !memcmp(ct->pe_data, p->pe_data, p->pe_data_len))
135 IP_VS_DBG_BUF(9, "SIP template match %s %s->%s:%d %s\n",
136 ip_vs_proto_name(p->protocol),
137 IP_VS_DEBUG_CALLID(p->pe_data, p->pe_data_len),
138 IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
139 ret ? "hit" : "not hit");
144 static u32 ip_vs_sip_hashkey_raw(const struct ip_vs_conn_param *p,
145 u32 initval, bool inverse)
147 return jhash(p->pe_data, p->pe_data_len, initval);
150 static int ip_vs_sip_show_pe_data(const struct ip_vs_conn *cp, char *buf)
152 memcpy(buf, cp->pe_data, cp->pe_data_len);
153 return cp->pe_data_len;
156 static struct ip_vs_pe ip_vs_sip_pe =
159 .refcnt = ATOMIC_INIT(0),
160 .module = THIS_MODULE,
161 .n_list = LIST_HEAD_INIT(ip_vs_sip_pe.n_list),
162 .fill_param = ip_vs_sip_fill_param,
163 .ct_match = ip_vs_sip_ct_match,
164 .hashkey_raw = ip_vs_sip_hashkey_raw,
165 .show_pe_data = ip_vs_sip_show_pe_data,
168 static int __init ip_vs_sip_init(void)
170 return register_ip_vs_pe(&ip_vs_sip_pe);
173 static void __exit ip_vs_sip_cleanup(void)
175 unregister_ip_vs_pe(&ip_vs_sip_pe);
179 module_init(ip_vs_sip_init);
180 module_exit(ip_vs_sip_cleanup);
181 MODULE_LICENSE("GPL");