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@@ -1,1366 +0,0 @@
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---- /dev/null
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-+++ b/include/linux/netfilter/nf_conntrack_rtsp.h
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-@@ -0,0 +1,63 @@
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-+/*
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-+ * RTSP extension for IP connection tracking.
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-+ * (C) 2003 by Tom Marshall <tmarshall at real.com>
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-+ * based on ip_conntrack_irc.h
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-+ *
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-+ * This program is free software; you can redistribute it and/or
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-+ * modify it under the terms of the GNU General Public License
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-+ * as published by the Free Software Foundation; either version
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-+ * 2 of the License, or (at your option) any later version.
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-+ */
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-+#ifndef _IP_CONNTRACK_RTSP_H
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-+#define _IP_CONNTRACK_RTSP_H
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-+
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-+//#define IP_NF_RTSP_DEBUG 1
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-+#define IP_NF_RTSP_VERSION "0.6.21"
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-+
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-+#ifdef __KERNEL__
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-+/* port block types */
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-+typedef enum {
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-+ pb_single, /* client_port=x */
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-+ pb_range, /* client_port=x-y */
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-+ pb_discon /* client_port=x/y (rtspbis) */
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-+} portblock_t;
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-+
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-+/* We record seq number and length of rtsp headers here, all in host order. */
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-+
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-+/*
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-+ * This structure is per expected connection. It is a member of struct
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-+ * ip_conntrack_expect. The TCP SEQ for the conntrack expect is stored
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-+ * there and we are expected to only store the length of the data which
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-+ * needs replaced. If a packet contains multiple RTSP messages, we create
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-+ * one expected connection per message.
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-+ *
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-+ * We use these variables to mark the entire header block. This may seem
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-+ * like overkill, but the nature of RTSP requires it. A header may appear
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-+ * multiple times in a message. We must treat two Transport headers the
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-+ * same as one Transport header with two entries.
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-+ */
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-+struct ip_ct_rtsp_expect
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-+{
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-+ u_int32_t len; /* length of header block */
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-+ portblock_t pbtype; /* Type of port block that was requested */
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-+ u_int16_t loport; /* Port that was requested, low or first */
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-+ u_int16_t hiport; /* Port that was requested, high or second */
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-+#if 0
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-+ uint method; /* RTSP method */
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-+ uint cseq; /* CSeq from request */
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-+#endif
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-+};
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-+
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-+extern unsigned int (*nf_nat_rtsp_hook)(struct sk_buff *skb,
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-+ enum ip_conntrack_info ctinfo,
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-+ unsigned int matchoff, unsigned int matchlen,
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-+ struct ip_ct_rtsp_expect *prtspexp,
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-+ struct nf_conntrack_expect *exp);
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-+
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-+extern void (*nf_nat_rtsp_hook_expectfn)(struct nf_conn *ct, struct nf_conntrack_expect *exp);
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-+
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-+#define RTSP_PORT 554
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-+
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-+#endif /* __KERNEL__ */
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-+
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-+#endif /* _IP_CONNTRACK_RTSP_H */
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---- /dev/null
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-+++ b/include/linux/netfilter_helpers.h
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-@@ -0,0 +1,133 @@
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-+/*
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-+ * Helpers for netfiler modules. This file provides implementations for basic
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-+ * functions such as strncasecmp(), etc.
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-+ *
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-+ * gcc will warn for defined but unused functions, so we only include the
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-+ * functions requested. The following macros are used:
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-+ * NF_NEED_STRNCASECMP nf_strncasecmp()
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-+ * NF_NEED_STRTOU16 nf_strtou16()
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-+ * NF_NEED_STRTOU32 nf_strtou32()
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-+ */
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-+#ifndef _NETFILTER_HELPERS_H
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-+#define _NETFILTER_HELPERS_H
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-+
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-+/* Only include these functions for kernel code. */
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-+#ifdef __KERNEL__
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-+
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-+#include <linux/ctype.h>
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-+#define iseol(c) ( (c) == '\r' || (c) == '\n' )
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-+
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-+/*
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-+ * The standard strncasecmp()
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-+ */
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-+#ifdef NF_NEED_STRNCASECMP
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-+static int
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-+nf_strncasecmp(const char* s1, const char* s2, u_int32_t len)
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-+{
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-+ if (s1 == NULL || s2 == NULL)
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-+ {
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-+ if (s1 == NULL && s2 == NULL)
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-+ {
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-+ return 0;
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-+ }
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-+ return (s1 == NULL) ? -1 : 1;
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-+ }
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-+ while (len > 0 && tolower(*s1) == tolower(*s2))
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-+ {
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-+ len--;
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-+ s1++;
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-+ s2++;
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-+ }
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-+ return ( (len == 0) ? 0 : (tolower(*s1) - tolower(*s2)) );
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-+}
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-+#endif /* NF_NEED_STRNCASECMP */
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-+
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-+/*
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-+ * Parse a string containing a 16-bit unsigned integer.
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-+ * Returns the number of chars used, or zero if no number is found.
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-+ */
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-+#ifdef NF_NEED_STRTOU16
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-+static int
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-+nf_strtou16(const char* pbuf, u_int16_t* pval)
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-+{
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-+ int n = 0;
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-+
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-+ *pval = 0;
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-+ while (isdigit(pbuf[n]))
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-+ {
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-+ *pval = (*pval * 10) + (pbuf[n] - '0');
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-+ n++;
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-+ }
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-+
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-+ return n;
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-+}
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-+#endif /* NF_NEED_STRTOU16 */
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-+
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-+/*
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-+ * Parse a string containing a 32-bit unsigned integer.
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-+ * Returns the number of chars used, or zero if no number is found.
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-+ */
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-+#ifdef NF_NEED_STRTOU32
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-+static int
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-+nf_strtou32(const char* pbuf, u_int32_t* pval)
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-+{
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-+ int n = 0;
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-+
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-+ *pval = 0;
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-+ while (pbuf[n] >= '0' && pbuf[n] <= '9')
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-+ {
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-+ *pval = (*pval * 10) + (pbuf[n] - '0');
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-+ n++;
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-+ }
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-+
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-+ return n;
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-+}
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-+#endif /* NF_NEED_STRTOU32 */
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-+
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-+/*
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-+ * Given a buffer and length, advance to the next line and mark the current
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-+ * line.
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-+ */
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-+#ifdef NF_NEED_NEXTLINE
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-+static int
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-+nf_nextline(char* p, uint len, uint* poff, uint* plineoff, uint* plinelen)
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-+{
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-+ uint off = *poff;
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-+ uint physlen = 0;
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-+
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-+ if (off >= len)
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-+ {
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-+ return 0;
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-+ }
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-+
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-+ while (p[off] != '\n')
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-+ {
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-+ if (len-off <= 1)
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-+ {
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-+ return 0;
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-+ }
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-+
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-+ physlen++;
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-+ off++;
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-+ }
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-+
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-+ /* if we saw a crlf, physlen needs adjusted */
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-+ if (physlen > 0 && p[off] == '\n' && p[off-1] == '\r')
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-+ {
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-+ physlen--;
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-+ }
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-+
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-+ /* advance past the newline */
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-+ off++;
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-+
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-+ *plineoff = *poff;
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-+ *plinelen = physlen;
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-+ *poff = off;
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-+
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-+ return 1;
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-+}
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-+#endif /* NF_NEED_NEXTLINE */
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-+
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-+#endif /* __KERNEL__ */
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-+
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-+#endif /* _NETFILTER_HELPERS_H */
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---- /dev/null
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-+++ b/include/linux/netfilter_mime.h
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-@@ -0,0 +1,89 @@
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-+/*
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-+ * MIME functions for netfilter modules. This file provides implementations
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-+ * for basic MIME parsing. MIME headers are used in many protocols, such as
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-+ * HTTP, RTSP, SIP, etc.
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-+ *
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-+ * gcc will warn for defined but unused functions, so we only include the
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-+ * functions requested. The following macros are used:
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-+ * NF_NEED_MIME_NEXTLINE nf_mime_nextline()
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-+ */
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-+#ifndef _NETFILTER_MIME_H
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-+#define _NETFILTER_MIME_H
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-+
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-+/* Only include these functions for kernel code. */
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-+#ifdef __KERNEL__
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-+
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-+#include <linux/ctype.h>
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-+
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-+/*
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-+ * Given a buffer and length, advance to the next line and mark the current
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-+ * line. If the current line is empty, *plinelen will be set to zero. If
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-+ * not, it will be set to the actual line length (including CRLF).
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-+ *
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-+ * 'line' in this context means logical line (includes LWS continuations).
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-+ * Returns 1 on success, 0 on failure.
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-+ */
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-+#ifdef NF_NEED_MIME_NEXTLINE
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-+static int
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-+nf_mime_nextline(char* p, uint len, uint* poff, uint* plineoff, uint* plinelen)
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-+{
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-+ uint off = *poff;
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-+ uint physlen = 0;
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-+ int is_first_line = 1;
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-+
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-+ if (off >= len)
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-+ {
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-+ return 0;
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-+ }
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-+
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-+ do
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-+ {
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-+ while (p[off] != '\n')
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-+ {
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-+ if (len-off <= 1)
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-+ {
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-+ return 0;
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-+ }
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-+
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-+ physlen++;
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-+ off++;
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-+ }
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-+
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-+ /* if we saw a crlf, physlen needs adjusted */
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-+ if (physlen > 0 && p[off] == '\n' && p[off-1] == '\r')
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-+ {
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-+ physlen--;
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-+ }
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-+
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-+ /* advance past the newline */
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-+ off++;
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-+
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-+ /* check for an empty line */
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-+ if (physlen == 0)
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-+ {
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-+ break;
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-+ }
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-+
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-+ /* check for colon on the first physical line */
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-+ if (is_first_line)
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-+ {
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-+ is_first_line = 0;
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-+ if (memchr(p+(*poff), ':', physlen) == NULL)
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-+ {
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-+ return 0;
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-+ }
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-+ }
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-+ }
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-+ while (p[off] == ' ' || p[off] == '\t');
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-+
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-+ *plineoff = *poff;
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-+ *plinelen = (physlen == 0) ? 0 : (off - *poff);
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-+ *poff = off;
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-+
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-+ return 1;
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-+}
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-+#endif /* NF_NEED_MIME_NEXTLINE */
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-+
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-+#endif /* __KERNEL__ */
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-+
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-+#endif /* _NETFILTER_MIME_H */
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---- a/net/ipv4/netfilter/Makefile
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-+++ b/net/ipv4/netfilter/Makefile
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-@@ -26,6 +26,7 @@ obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_am
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- obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
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- obj-$(CONFIG_NF_NAT_H323) += nf_nat_h323.o
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- obj-$(CONFIG_NF_NAT_IRC) += nf_nat_irc.o
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-+obj-$(CONFIG_NF_NAT_RTSP) += nf_nat_rtsp.o
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- obj-$(CONFIG_NF_NAT_PPTP) += nf_nat_pptp.o
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- obj-$(CONFIG_NF_NAT_SIP) += nf_nat_sip.o
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- obj-$(CONFIG_NF_NAT_SNMP_BASIC) += nf_nat_snmp_basic.o
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---- a/net/netfilter/Kconfig
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-+++ b/net/netfilter/Kconfig
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-@@ -267,6 +267,16 @@ config NF_CONNTRACK_TFTP
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-
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- To compile it as a module, choose M here. If unsure, say N.
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-
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-+config NF_CONNTRACK_RTSP
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-+ tristate "RTSP protocol support"
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-+ depends on NF_CONNTRACK
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-+ help
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-+ Support the RTSP protocol. This allows UDP transports to be setup
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-+ properly, including RTP and RDT.
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-+
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-+ If you want to compile it as a module, say 'M' here and read
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-+ Documentation/modules.txt. If unsure, say 'Y'.
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-+
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- config NF_CT_NETLINK
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- tristate 'Connection tracking netlink interface'
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- select NETFILTER_NETLINK
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---- a/net/netfilter/Makefile
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-+++ b/net/netfilter/Makefile
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-@@ -33,6 +33,7 @@ obj-$(CONFIG_NF_CONNTRACK_PPTP) += nf_co
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- obj-$(CONFIG_NF_CONNTRACK_SANE) += nf_conntrack_sane.o
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- obj-$(CONFIG_NF_CONNTRACK_SIP) += nf_conntrack_sip.o
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- obj-$(CONFIG_NF_CONNTRACK_TFTP) += nf_conntrack_tftp.o
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-+obj-$(CONFIG_NF_CONNTRACK_RTSP) += nf_conntrack_rtsp.o
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-
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- # transparent proxy support
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- obj-$(CONFIG_NETFILTER_TPROXY) += nf_tproxy_core.o
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---- a/net/ipv4/netfilter/Kconfig
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-+++ b/net/ipv4/netfilter/Kconfig
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-@@ -257,6 +257,11 @@ config NF_NAT_IRC
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- depends on NF_CONNTRACK && NF_NAT
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- default NF_NAT && NF_CONNTRACK_IRC
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-
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-+config NF_NAT_RTSP
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-+ tristate
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-+ depends on IP_NF_IPTABLES && NF_CONNTRACK && NF_NAT
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-+ default NF_NAT && NF_CONNTRACK_RTSP
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-+
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- config NF_NAT_TFTP
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- tristate
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- depends on NF_CONNTRACK && NF_NAT
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---- /dev/null
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-+++ b/net/netfilter/nf_conntrack_rtsp.c
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-@@ -0,0 +1,517 @@
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-+/*
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-+ * RTSP extension for IP connection tracking
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-+ * (C) 2003 by Tom Marshall <tmarshall at real.com>
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-+ * based on ip_conntrack_irc.c
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-+ *
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-+ * This program is free software; you can redistribute it and/or
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-+ * modify it under the terms of the GNU General Public License
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-+ * as published by the Free Software Foundation; either version
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-+ * 2 of the License, or (at your option) any later version.
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-+ *
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-+ * Module load syntax:
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-+ * insmod nf_conntrack_rtsp.o ports=port1,port2,...port<MAX_PORTS>
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-+ * max_outstanding=n setup_timeout=secs
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-+ *
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-+ * If no ports are specified, the default will be port 554.
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-+ *
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-+ * With max_outstanding you can define the maximum number of not yet
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-+ * answered SETUP requests per RTSP session (default 8).
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-+ * With setup_timeout you can specify how long the system waits for
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-+ * an expected data channel (default 300 seconds).
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-+ *
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-+ * 2005-02-13: Harald Welte <laforge at netfilter.org>
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-+ * - port to 2.6
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|
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-+ * - update to recent post-2.6.11 api changes
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|
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-+ * 2006-09-14: Steven Van Acker <deepstar at singularity.be>
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|
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-+ * - removed calls to NAT code from conntrack helper: NAT no longer needed to use rtsp-conntrack
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-+ * 2007-04-18: Michael Guntsche <mike at it-loops.com>
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|
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-+ * - Port to new NF API
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-+ */
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-+
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-+#include <linux/module.h>
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-+#include <linux/netfilter.h>
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-+#include <linux/ip.h>
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-+#include <linux/inet.h>
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-+#include <net/tcp.h>
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-+
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-+#include <net/netfilter/nf_conntrack.h>
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|
|
-+#include <net/netfilter/nf_conntrack_expect.h>
|
|
|
-+#include <net/netfilter/nf_conntrack_helper.h>
|
|
|
-+#include <linux/netfilter/nf_conntrack_rtsp.h>
|
|
|
-+
|
|
|
-+#define NF_NEED_STRNCASECMP
|
|
|
-+#define NF_NEED_STRTOU16
|
|
|
-+#define NF_NEED_STRTOU32
|
|
|
-+#define NF_NEED_NEXTLINE
|
|
|
-+#include <linux/netfilter_helpers.h>
|
|
|
-+#define NF_NEED_MIME_NEXTLINE
|
|
|
-+#include <linux/netfilter_mime.h>
|
|
|
-+
|
|
|
-+#include <linux/ctype.h>
|
|
|
-+#define MAX_SIMUL_SETUP 8 /* XXX: use max_outstanding */
|
|
|
-+#define INFOP(fmt, args...) printk(KERN_INFO "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
|
|
|
-+#if 0
|
|
|
-+#define DEBUGP(fmt, args...) printk(KERN_DEBUG "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
|
|
|
-+#else
|
|
|
-+#define DEBUGP(fmt, args...)
|
|
|
-+#endif
|
|
|
-+
|
|
|
-+#define MAX_PORTS 8
|
|
|
-+static int ports[MAX_PORTS];
|
|
|
-+static int num_ports = 0;
|
|
|
-+static int max_outstanding = 8;
|
|
|
-+static unsigned int setup_timeout = 300;
|
|
|
-+
|
|
|
-+MODULE_AUTHOR("Tom Marshall <tmarshall at real.com>");
|
|
|
-+MODULE_DESCRIPTION("RTSP connection tracking module");
|
|
|
-+MODULE_LICENSE("GPL");
|
|
|
-+module_param_array(ports, int, &num_ports, 0400);
|
|
|
-+MODULE_PARM_DESC(ports, "port numbers of RTSP servers");
|
|
|
-+module_param(max_outstanding, int, 0400);
|
|
|
-+MODULE_PARM_DESC(max_outstanding, "max number of outstanding SETUP requests per RTSP session");
|
|
|
-+module_param(setup_timeout, int, 0400);
|
|
|
-+MODULE_PARM_DESC(setup_timeout, "timeout on for unestablished data channels");
|
|
|
-+
|
|
|
-+static char *rtsp_buffer;
|
|
|
-+static DEFINE_SPINLOCK(rtsp_buffer_lock);
|
|
|
-+
|
|
|
-+unsigned int (*nf_nat_rtsp_hook)(struct sk_buff *skb,
|
|
|
-+ enum ip_conntrack_info ctinfo,
|
|
|
-+ unsigned int matchoff, unsigned int matchlen,struct ip_ct_rtsp_expect* prtspexp,
|
|
|
-+ struct nf_conntrack_expect *exp);
|
|
|
-+void (*nf_nat_rtsp_hook_expectfn)(struct nf_conn *ct, struct nf_conntrack_expect *exp);
|
|
|
-+
|
|
|
-+EXPORT_SYMBOL_GPL(nf_nat_rtsp_hook);
|
|
|
-+
|
|
|
-+/*
|
|
|
-+ * Max mappings we will allow for one RTSP connection (for RTP, the number
|
|
|
-+ * of allocated ports is twice this value). Note that SMIL burns a lot of
|
|
|
-+ * ports so keep this reasonably high. If this is too low, you will see a
|
|
|
-+ * lot of "no free client map entries" messages.
|
|
|
-+ */
|
|
|
-+#define MAX_PORT_MAPS 16
|
|
|
-+
|
|
|
-+/*** default port list was here in the masq code: 554, 3030, 4040 ***/
|
|
|
-+
|
|
|
-+#define SKIP_WSPACE(ptr,len,off) while(off < len && isspace(*(ptr+off))) { off++; }
|
|
|
-+
|
|
|
-+/*
|
|
|
-+ * Parse an RTSP packet.
|
|
|
-+ *
|
|
|
-+ * Returns zero if parsing failed.
|
|
|
-+ *
|
|
|
-+ * Parameters:
|
|
|
-+ * IN ptcp tcp data pointer
|
|
|
-+ * IN tcplen tcp data len
|
|
|
-+ * IN/OUT ptcpoff points to current tcp offset
|
|
|
-+ * OUT phdrsoff set to offset of rtsp headers
|
|
|
-+ * OUT phdrslen set to length of rtsp headers
|
|
|
-+ * OUT pcseqoff set to offset of CSeq header
|
|
|
-+ * OUT pcseqlen set to length of CSeq header
|
|
|
-+ */
|
|
|
-+static int
|
|
|
-+rtsp_parse_message(char* ptcp, uint tcplen, uint* ptcpoff,
|
|
|
-+ uint* phdrsoff, uint* phdrslen,
|
|
|
-+ uint* pcseqoff, uint* pcseqlen,
|
|
|
-+ uint* transoff, uint* translen)
|
|
|
-+{
|
|
|
-+ uint entitylen = 0;
|
|
|
-+ uint lineoff;
|
|
|
-+ uint linelen;
|
|
|
-+
|
|
|
-+ if (!nf_nextline(ptcp, tcplen, ptcpoff, &lineoff, &linelen))
|
|
|
-+ return 0;
|
|
|
-+
|
|
|
-+ *phdrsoff = *ptcpoff;
|
|
|
-+ while (nf_mime_nextline(ptcp, tcplen, ptcpoff, &lineoff, &linelen)) {
|
|
|
-+ if (linelen == 0) {
|
|
|
-+ if (entitylen > 0)
|
|
|
-+ *ptcpoff += min(entitylen, tcplen - *ptcpoff);
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ if (lineoff+linelen > tcplen) {
|
|
|
-+ INFOP("!! overrun !!\n");
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ if (nf_strncasecmp(ptcp+lineoff, "CSeq:", 5) == 0) {
|
|
|
-+ *pcseqoff = lineoff;
|
|
|
-+ *pcseqlen = linelen;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ if (nf_strncasecmp(ptcp+lineoff, "Transport:", 10) == 0) {
|
|
|
-+ *transoff = lineoff;
|
|
|
-+ *translen = linelen;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ if (nf_strncasecmp(ptcp+lineoff, "Content-Length:", 15) == 0) {
|
|
|
-+ uint off = lineoff+15;
|
|
|
-+ SKIP_WSPACE(ptcp+lineoff, linelen, off);
|
|
|
-+ nf_strtou32(ptcp+off, &entitylen);
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ *phdrslen = (*ptcpoff) - (*phdrsoff);
|
|
|
-+
|
|
|
-+ return 1;
|
|
|
-+}
|
|
|
-+
|
|
|
-+/*
|
|
|
-+ * Find lo/hi client ports (if any) in transport header
|
|
|
-+ * In:
|
|
|
-+ * ptcp, tcplen = packet
|
|
|
-+ * tranoff, tranlen = buffer to search
|
|
|
-+ *
|
|
|
-+ * Out:
|
|
|
-+ * pport_lo, pport_hi = lo/hi ports (host endian)
|
|
|
-+ *
|
|
|
-+ * Returns nonzero if any client ports found
|
|
|
-+ *
|
|
|
-+ * Note: it is valid (and expected) for the client to request multiple
|
|
|
-+ * transports, so we need to parse the entire line.
|
|
|
-+ */
|
|
|
-+static int
|
|
|
-+rtsp_parse_transport(char* ptran, uint tranlen,
|
|
|
-+ struct ip_ct_rtsp_expect* prtspexp)
|
|
|
-+{
|
|
|
-+ int rc = 0;
|
|
|
-+ uint off = 0;
|
|
|
-+
|
|
|
-+ if (tranlen < 10 || !iseol(ptran[tranlen-1]) ||
|
|
|
-+ nf_strncasecmp(ptran, "Transport:", 10) != 0) {
|
|
|
-+ INFOP("sanity check failed\n");
|
|
|
-+ return 0;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ DEBUGP("tran='%.*s'\n", (int)tranlen, ptran);
|
|
|
-+ off += 10;
|
|
|
-+ SKIP_WSPACE(ptran, tranlen, off);
|
|
|
-+
|
|
|
-+ /* Transport: tran;field;field=val,tran;field;field=val,... */
|
|
|
-+ while (off < tranlen) {
|
|
|
-+ const char* pparamend;
|
|
|
-+ uint nextparamoff;
|
|
|
-+
|
|
|
-+ pparamend = memchr(ptran+off, ',', tranlen-off);
|
|
|
-+ pparamend = (pparamend == NULL) ? ptran+tranlen : pparamend+1;
|
|
|
-+ nextparamoff = pparamend-ptran;
|
|
|
-+
|
|
|
-+ while (off < nextparamoff) {
|
|
|
-+ const char* pfieldend;
|
|
|
-+ uint nextfieldoff;
|
|
|
-+
|
|
|
-+ pfieldend = memchr(ptran+off, ';', nextparamoff-off);
|
|
|
-+ nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
|
|
|
-+
|
|
|
-+ if (strncmp(ptran+off, "client_port=", 12) == 0) {
|
|
|
-+ u_int16_t port;
|
|
|
-+ uint numlen;
|
|
|
-+
|
|
|
-+ off += 12;
|
|
|
-+ numlen = nf_strtou16(ptran+off, &port);
|
|
|
-+ off += numlen;
|
|
|
-+ if (prtspexp->loport != 0 && prtspexp->loport != port)
|
|
|
-+ DEBUGP("multiple ports found, port %hu ignored\n", port);
|
|
|
-+ else {
|
|
|
-+ DEBUGP("lo port found : %hu\n", port);
|
|
|
-+ prtspexp->loport = prtspexp->hiport = port;
|
|
|
-+ if (ptran[off] == '-') {
|
|
|
-+ off++;
|
|
|
-+ numlen = nf_strtou16(ptran+off, &port);
|
|
|
-+ off += numlen;
|
|
|
-+ prtspexp->pbtype = pb_range;
|
|
|
-+ prtspexp->hiport = port;
|
|
|
-+
|
|
|
-+ // If we have a range, assume rtp:
|
|
|
-+ // loport must be even, hiport must be loport+1
|
|
|
-+ if ((prtspexp->loport & 0x0001) != 0 ||
|
|
|
-+ prtspexp->hiport != prtspexp->loport+1) {
|
|
|
-+ DEBUGP("incorrect range: %hu-%hu, correcting\n",
|
|
|
-+ prtspexp->loport, prtspexp->hiport);
|
|
|
-+ prtspexp->loport &= 0xfffe;
|
|
|
-+ prtspexp->hiport = prtspexp->loport+1;
|
|
|
-+ }
|
|
|
-+ } else if (ptran[off] == '/') {
|
|
|
-+ off++;
|
|
|
-+ numlen = nf_strtou16(ptran+off, &port);
|
|
|
-+ off += numlen;
|
|
|
-+ prtspexp->pbtype = pb_discon;
|
|
|
-+ prtspexp->hiport = port;
|
|
|
-+ }
|
|
|
-+ rc = 1;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ /*
|
|
|
-+ * Note we don't look for the destination parameter here.
|
|
|
-+ * If we are using NAT, the NAT module will handle it. If not,
|
|
|
-+ * and the client is sending packets elsewhere, the expectation
|
|
|
-+ * will quietly time out.
|
|
|
-+ */
|
|
|
-+
|
|
|
-+ off = nextfieldoff;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ off = nextparamoff;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ return rc;
|
|
|
-+}
|
|
|
-+
|
|
|
-+void expected(struct nf_conn *ct, struct nf_conntrack_expect *exp)
|
|
|
-+{
|
|
|
-+ if(nf_nat_rtsp_hook_expectfn) {
|
|
|
-+ nf_nat_rtsp_hook_expectfn(ct,exp);
|
|
|
-+ }
|
|
|
-+}
|
|
|
-+
|
|
|
-+/*** conntrack functions ***/
|
|
|
-+
|
|
|
-+/* outbound packet: client->server */
|
|
|
-+
|
|
|
-+static inline int
|
|
|
-+help_out(struct sk_buff *skb, unsigned char *rb_ptr, unsigned int datalen,
|
|
|
-+ struct nf_conn *ct, enum ip_conntrack_info ctinfo)
|
|
|
-+{
|
|
|
-+ struct ip_ct_rtsp_expect expinfo;
|
|
|
-+
|
|
|
-+ int dir = CTINFO2DIR(ctinfo); /* = IP_CT_DIR_ORIGINAL */
|
|
|
-+ //struct tcphdr* tcph = (void*)iph + iph->ihl * 4;
|
|
|
-+ //uint tcplen = pktlen - iph->ihl * 4;
|
|
|
-+ char* pdata = rb_ptr;
|
|
|
-+ //uint datalen = tcplen - tcph->doff * 4;
|
|
|
-+ uint dataoff = 0;
|
|
|
-+ int ret = NF_ACCEPT;
|
|
|
-+
|
|
|
-+ struct nf_conntrack_expect *exp;
|
|
|
-+
|
|
|
-+ __be16 be_loport;
|
|
|
-+
|
|
|
-+ memset(&expinfo, 0, sizeof(expinfo));
|
|
|
-+
|
|
|
-+ while (dataoff < datalen) {
|
|
|
-+ uint cmdoff = dataoff;
|
|
|
-+ uint hdrsoff = 0;
|
|
|
-+ uint hdrslen = 0;
|
|
|
-+ uint cseqoff = 0;
|
|
|
-+ uint cseqlen = 0;
|
|
|
-+ uint transoff = 0;
|
|
|
-+ uint translen = 0;
|
|
|
-+ uint off;
|
|
|
-+
|
|
|
-+ if (!rtsp_parse_message(pdata, datalen, &dataoff,
|
|
|
-+ &hdrsoff, &hdrslen,
|
|
|
-+ &cseqoff, &cseqlen,
|
|
|
-+ &transoff, &translen))
|
|
|
-+ break; /* not a valid message */
|
|
|
-+
|
|
|
-+ if (strncmp(pdata+cmdoff, "SETUP ", 6) != 0)
|
|
|
-+ continue; /* not a SETUP message */
|
|
|
-+ DEBUGP("found a setup message\n");
|
|
|
-+
|
|
|
-+ off = 0;
|
|
|
-+ if(translen) {
|
|
|
-+ rtsp_parse_transport(pdata+transoff, translen, &expinfo);
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ if (expinfo.loport == 0) {
|
|
|
-+ DEBUGP("no udp transports found\n");
|
|
|
-+ continue; /* no udp transports found */
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ DEBUGP("udp transport found, ports=(%d,%hu,%hu)\n",
|
|
|
-+ (int)expinfo.pbtype, expinfo.loport, expinfo.hiport);
|
|
|
-+
|
|
|
-+ exp = nf_ct_expect_alloc(ct);
|
|
|
-+ if (!exp) {
|
|
|
-+ ret = NF_DROP;
|
|
|
-+ goto out;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ be_loport = htons(expinfo.loport);
|
|
|
-+
|
|
|
-+ nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
|
|
|
-+ ct->tuplehash[!dir].tuple.src.l3num,
|
|
|
-+ &ct->tuplehash[!dir].tuple.src.u3, &ct->tuplehash[!dir].tuple.dst.u3,
|
|
|
-+ IPPROTO_UDP, NULL, &be_loport);
|
|
|
-+
|
|
|
-+ exp->master = ct;
|
|
|
-+
|
|
|
-+ exp->expectfn = expected;
|
|
|
-+ exp->flags = 0;
|
|
|
-+
|
|
|
-+ if (expinfo.pbtype == pb_range) {
|
|
|
-+ DEBUGP("Changing expectation mask to handle multiple ports\n");
|
|
|
-+ exp->mask.src.u.udp.port = 0xfffe;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ DEBUGP("expect_related %u.%u.%u.%u:%u-%u.%u.%u.%u:%u\n",
|
|
|
-+ NIPQUAD(exp->tuple.src.u3.ip),
|
|
|
-+ ntohs(exp->tuple.src.u.udp.port),
|
|
|
-+ NIPQUAD(exp->tuple.dst.u3.ip),
|
|
|
-+ ntohs(exp->tuple.dst.u.udp.port));
|
|
|
-+
|
|
|
-+ if (nf_nat_rtsp_hook)
|
|
|
-+ /* pass the request off to the nat helper */
|
|
|
-+ ret = nf_nat_rtsp_hook(skb, ctinfo, hdrsoff, hdrslen, &expinfo, exp);
|
|
|
-+ else if (nf_ct_expect_related(exp) != 0) {
|
|
|
-+ INFOP("nf_ct_expect_related failed\n");
|
|
|
-+ ret = NF_DROP;
|
|
|
-+ }
|
|
|
-+ nf_ct_expect_put(exp);
|
|
|
-+ goto out;
|
|
|
-+ }
|
|
|
-+out:
|
|
|
-+
|
|
|
-+ return ret;
|
|
|
-+}
|
|
|
-+
|
|
|
-+
|
|
|
-+static inline int
|
|
|
-+help_in(struct sk_buff *skb, size_t pktlen,
|
|
|
-+ struct nf_conn* ct, enum ip_conntrack_info ctinfo)
|
|
|
-+{
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+}
|
|
|
-+
|
|
|
-+static int help(struct sk_buff *skb, unsigned int protoff,
|
|
|
-+ struct nf_conn *ct, enum ip_conntrack_info ctinfo)
|
|
|
-+{
|
|
|
-+ struct tcphdr _tcph, *th;
|
|
|
-+ unsigned int dataoff, datalen;
|
|
|
-+ char *rb_ptr;
|
|
|
-+ int ret = NF_DROP;
|
|
|
-+
|
|
|
-+ /* Until there's been traffic both ways, don't look in packets. */
|
|
|
-+ if (ctinfo != IP_CT_ESTABLISHED &&
|
|
|
-+ ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
|
|
|
-+ DEBUGP("conntrackinfo = %u\n", ctinfo);
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ /* Not whole TCP header? */
|
|
|
-+ th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
|
|
|
-+
|
|
|
-+ if (!th)
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+
|
|
|
-+ /* No data ? */
|
|
|
-+ dataoff = protoff + th->doff*4;
|
|
|
-+ datalen = skb->len - dataoff;
|
|
|
-+ if (dataoff >= skb->len)
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+
|
|
|
-+ spin_lock_bh(&rtsp_buffer_lock);
|
|
|
-+ rb_ptr = skb_header_pointer(skb, dataoff,
|
|
|
-+ skb->len - dataoff, rtsp_buffer);
|
|
|
-+ BUG_ON(rb_ptr == NULL);
|
|
|
-+
|
|
|
-+#if 0
|
|
|
-+ /* Checksum invalid? Ignore. */
|
|
|
-+ /* FIXME: Source route IP option packets --RR */
|
|
|
-+ if (tcp_v4_check(tcph, tcplen, iph->saddr, iph->daddr,
|
|
|
-+ csum_partial((char*)tcph, tcplen, 0)))
|
|
|
-+ {
|
|
|
-+ DEBUGP("bad csum: %p %u %u.%u.%u.%u %u.%u.%u.%u\n",
|
|
|
-+ tcph, tcplen, NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+ }
|
|
|
-+#endif
|
|
|
-+
|
|
|
-+ switch (CTINFO2DIR(ctinfo)) {
|
|
|
-+ case IP_CT_DIR_ORIGINAL:
|
|
|
-+ ret = help_out(skb, rb_ptr, datalen, ct, ctinfo);
|
|
|
-+ break;
|
|
|
-+ case IP_CT_DIR_REPLY:
|
|
|
-+ DEBUGP("IP_CT_DIR_REPLY\n");
|
|
|
-+ /* inbound packet: server->client */
|
|
|
-+ ret = NF_ACCEPT;
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ spin_unlock_bh(&rtsp_buffer_lock);
|
|
|
-+
|
|
|
-+ return ret;
|
|
|
-+}
|
|
|
-+
|
|
|
-+static struct nf_conntrack_helper rtsp_helpers[MAX_PORTS];
|
|
|
-+static char rtsp_names[MAX_PORTS][10];
|
|
|
-+static struct nf_conntrack_expect_policy rtsp_expect_policy;
|
|
|
-+
|
|
|
-+/* This function is intentionally _NOT_ defined as __exit */
|
|
|
-+static void
|
|
|
-+fini(void)
|
|
|
-+{
|
|
|
-+ int i;
|
|
|
-+ for (i = 0; i < num_ports; i++) {
|
|
|
-+ DEBUGP("unregistering port %d\n", ports[i]);
|
|
|
-+ nf_conntrack_helper_unregister(&rtsp_helpers[i]);
|
|
|
-+ }
|
|
|
-+ kfree(rtsp_buffer);
|
|
|
-+}
|
|
|
-+
|
|
|
-+static int __init
|
|
|
-+init(void)
|
|
|
-+{
|
|
|
-+ int i, ret;
|
|
|
-+ struct nf_conntrack_helper *hlpr;
|
|
|
-+ char *tmpname;
|
|
|
-+
|
|
|
-+ printk("nf_conntrack_rtsp v" IP_NF_RTSP_VERSION " loading\n");
|
|
|
-+
|
|
|
-+ if (max_outstanding < 1) {
|
|
|
-+ printk("nf_conntrack_rtsp: max_outstanding must be a positive integer\n");
|
|
|
-+ return -EBUSY;
|
|
|
-+ }
|
|
|
-+ if (setup_timeout < 0) {
|
|
|
-+ printk("nf_conntrack_rtsp: setup_timeout must be a positive integer\n");
|
|
|
-+ return -EBUSY;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ rtsp_expect_policy.max_expected = max_outstanding;
|
|
|
-+ rtsp_expect_policy.timeout = setup_timeout;
|
|
|
-+
|
|
|
-+ rtsp_buffer = kmalloc(65536, GFP_KERNEL);
|
|
|
-+ if (!rtsp_buffer)
|
|
|
-+ return -ENOMEM;
|
|
|
-+
|
|
|
-+ /* If no port given, default to standard rtsp port */
|
|
|
-+ if (ports[0] == 0) {
|
|
|
-+ ports[0] = RTSP_PORT;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ for (i = 0; (i < MAX_PORTS) && ports[i]; i++) {
|
|
|
-+ hlpr = &rtsp_helpers[i];
|
|
|
-+ memset(hlpr, 0, sizeof(struct nf_conntrack_helper));
|
|
|
-+ hlpr->tuple.src.u.tcp.port = htons(ports[i]);
|
|
|
-+ hlpr->tuple.dst.protonum = IPPROTO_TCP;
|
|
|
-+ hlpr->expect_policy = &rtsp_expect_policy;
|
|
|
-+ hlpr->me = THIS_MODULE;
|
|
|
-+ hlpr->help = help;
|
|
|
-+
|
|
|
-+ tmpname = &rtsp_names[i][0];
|
|
|
-+ if (ports[i] == RTSP_PORT) {
|
|
|
-+ sprintf(tmpname, "rtsp");
|
|
|
-+ } else {
|
|
|
-+ sprintf(tmpname, "rtsp-%d", i);
|
|
|
-+ }
|
|
|
-+ hlpr->name = tmpname;
|
|
|
-+
|
|
|
-+ DEBUGP("port #%d: %d\n", i, ports[i]);
|
|
|
-+
|
|
|
-+ ret = nf_conntrack_helper_register(hlpr);
|
|
|
-+
|
|
|
-+ if (ret) {
|
|
|
-+ printk("nf_conntrack_rtsp: ERROR registering port %d\n", ports[i]);
|
|
|
-+ fini();
|
|
|
-+ return -EBUSY;
|
|
|
-+ }
|
|
|
-+ num_ports++;
|
|
|
-+ }
|
|
|
-+ return 0;
|
|
|
-+}
|
|
|
-+
|
|
|
-+module_init(init);
|
|
|
-+module_exit(fini);
|
|
|
-+
|
|
|
-+EXPORT_SYMBOL(nf_nat_rtsp_hook_expectfn);
|
|
|
-+
|
|
|
---- /dev/null
|
|
|
-+++ b/net/ipv4/netfilter/nf_nat_rtsp.c
|
|
|
-@@ -0,0 +1,496 @@
|
|
|
-+/*
|
|
|
-+ * RTSP extension for TCP NAT alteration
|
|
|
-+ * (C) 2003 by Tom Marshall <tmarshall at real.com>
|
|
|
-+ * based on ip_nat_irc.c
|
|
|
-+ *
|
|
|
-+ * 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.
|
|
|
-+ *
|
|
|
-+ * Module load syntax:
|
|
|
-+ * insmod nf_nat_rtsp.o ports=port1,port2,...port<MAX_PORTS>
|
|
|
-+ * stunaddr=<address>
|
|
|
-+ * destaction=[auto|strip|none]
|
|
|
-+ *
|
|
|
-+ * If no ports are specified, the default will be port 554 only.
|
|
|
-+ *
|
|
|
-+ * stunaddr specifies the address used to detect that a client is using STUN.
|
|
|
-+ * If this address is seen in the destination parameter, it is assumed that
|
|
|
-+ * the client has already punched a UDP hole in the firewall, so we don't
|
|
|
-+ * mangle the client_port. If none is specified, it is autodetected. It
|
|
|
-+ * only needs to be set if you have multiple levels of NAT. It should be
|
|
|
-+ * set to the external address that the STUN clients detect. Note that in
|
|
|
-+ * this case, it will not be possible for clients to use UDP with servers
|
|
|
-+ * between the NATs.
|
|
|
-+ *
|
|
|
-+ * If no destaction is specified, auto is used.
|
|
|
-+ * destaction=auto: strip destination parameter if it is not stunaddr.
|
|
|
-+ * destaction=strip: always strip destination parameter (not recommended).
|
|
|
-+ * destaction=none: do not touch destination parameter (not recommended).
|
|
|
-+ */
|
|
|
-+
|
|
|
-+#include <linux/module.h>
|
|
|
-+#include <net/tcp.h>
|
|
|
-+#include <net/netfilter/nf_nat_helper.h>
|
|
|
-+#include <net/netfilter/nf_nat_rule.h>
|
|
|
-+#include <linux/netfilter/nf_conntrack_rtsp.h>
|
|
|
-+#include <net/netfilter/nf_conntrack_expect.h>
|
|
|
-+
|
|
|
-+#include <linux/inet.h>
|
|
|
-+#include <linux/ctype.h>
|
|
|
-+#define NF_NEED_STRNCASECMP
|
|
|
-+#define NF_NEED_STRTOU16
|
|
|
-+#include <linux/netfilter_helpers.h>
|
|
|
-+#define NF_NEED_MIME_NEXTLINE
|
|
|
-+#include <linux/netfilter_mime.h>
|
|
|
-+
|
|
|
-+#define INFOP(fmt, args...) printk(KERN_INFO "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
|
|
|
-+#if 0
|
|
|
-+#define DEBUGP(fmt, args...) printk(KERN_DEBUG "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
|
|
|
-+#else
|
|
|
-+#define DEBUGP(fmt, args...)
|
|
|
-+#endif
|
|
|
-+
|
|
|
-+#define MAX_PORTS 8
|
|
|
-+#define DSTACT_AUTO 0
|
|
|
-+#define DSTACT_STRIP 1
|
|
|
-+#define DSTACT_NONE 2
|
|
|
-+
|
|
|
-+static char* stunaddr = NULL;
|
|
|
-+static char* destaction = NULL;
|
|
|
-+
|
|
|
-+static u_int32_t extip = 0;
|
|
|
-+static int dstact = 0;
|
|
|
-+
|
|
|
-+MODULE_AUTHOR("Tom Marshall <tmarshall at real.com>");
|
|
|
-+MODULE_DESCRIPTION("RTSP network address translation module");
|
|
|
-+MODULE_LICENSE("GPL");
|
|
|
-+module_param(stunaddr, charp, 0644);
|
|
|
-+MODULE_PARM_DESC(stunaddr, "Address for detecting STUN");
|
|
|
-+module_param(destaction, charp, 0644);
|
|
|
-+MODULE_PARM_DESC(destaction, "Action for destination parameter (auto/strip/none)");
|
|
|
-+
|
|
|
-+#define SKIP_WSPACE(ptr,len,off) while(off < len && isspace(*(ptr+off))) { off++; }
|
|
|
-+
|
|
|
-+/*** helper functions ***/
|
|
|
-+
|
|
|
-+static void
|
|
|
-+get_skb_tcpdata(struct sk_buff* skb, char** pptcpdata, uint* ptcpdatalen)
|
|
|
-+{
|
|
|
-+ struct iphdr* iph = ip_hdr(skb);
|
|
|
-+ struct tcphdr* tcph = (void *)iph + ip_hdrlen(skb);
|
|
|
-+
|
|
|
-+ *pptcpdata = (char*)tcph + tcph->doff*4;
|
|
|
-+ *ptcpdatalen = ((char*)skb_transport_header(skb) + skb->len) - *pptcpdata;
|
|
|
-+}
|
|
|
-+
|
|
|
-+/*** nat functions ***/
|
|
|
-+
|
|
|
-+/*
|
|
|
-+ * Mangle the "Transport:" header:
|
|
|
-+ * - Replace all occurences of "client_port=<spec>"
|
|
|
-+ * - Handle destination parameter
|
|
|
-+ *
|
|
|
-+ * In:
|
|
|
-+ * ct, ctinfo = conntrack context
|
|
|
-+ * skb = packet
|
|
|
-+ * tranoff = Transport header offset from TCP data
|
|
|
-+ * tranlen = Transport header length (incl. CRLF)
|
|
|
-+ * rport_lo = replacement low port (host endian)
|
|
|
-+ * rport_hi = replacement high port (host endian)
|
|
|
-+ *
|
|
|
-+ * Returns packet size difference.
|
|
|
-+ *
|
|
|
-+ * Assumes that a complete transport header is present, ending with CR or LF
|
|
|
-+ */
|
|
|
-+static int
|
|
|
-+rtsp_mangle_tran(enum ip_conntrack_info ctinfo,
|
|
|
-+ struct nf_conntrack_expect* exp,
|
|
|
-+ struct ip_ct_rtsp_expect* prtspexp,
|
|
|
-+ struct sk_buff* skb, uint tranoff, uint tranlen)
|
|
|
-+{
|
|
|
-+ char* ptcp;
|
|
|
-+ uint tcplen;
|
|
|
-+ char* ptran;
|
|
|
-+ char rbuf1[16]; /* Replacement buffer (one port) */
|
|
|
-+ uint rbuf1len; /* Replacement len (one port) */
|
|
|
-+ char rbufa[16]; /* Replacement buffer (all ports) */
|
|
|
-+ uint rbufalen; /* Replacement len (all ports) */
|
|
|
-+ u_int32_t newip;
|
|
|
-+ u_int16_t loport, hiport;
|
|
|
-+ uint off = 0;
|
|
|
-+ uint diff; /* Number of bytes we removed */
|
|
|
-+
|
|
|
-+ struct nf_conn *ct = exp->master;
|
|
|
-+ struct nf_conntrack_tuple *t;
|
|
|
-+
|
|
|
-+ char szextaddr[15+1];
|
|
|
-+ uint extaddrlen;
|
|
|
-+ int is_stun;
|
|
|
-+
|
|
|
-+ get_skb_tcpdata(skb, &ptcp, &tcplen);
|
|
|
-+ ptran = ptcp+tranoff;
|
|
|
-+
|
|
|
-+ if (tranoff+tranlen > tcplen || tcplen-tranoff < tranlen ||
|
|
|
-+ tranlen < 10 || !iseol(ptran[tranlen-1]) ||
|
|
|
-+ nf_strncasecmp(ptran, "Transport:", 10) != 0)
|
|
|
-+ {
|
|
|
-+ INFOP("sanity check failed\n");
|
|
|
-+ return 0;
|
|
|
-+ }
|
|
|
-+ off += 10;
|
|
|
-+ SKIP_WSPACE(ptcp+tranoff, tranlen, off);
|
|
|
-+
|
|
|
-+ newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip;
|
|
|
-+ t = &exp->tuple;
|
|
|
-+ t->dst.u3.ip = newip;
|
|
|
-+
|
|
|
-+ extaddrlen = extip ? sprintf(szextaddr, "%u.%u.%u.%u", NIPQUAD(extip))
|
|
|
-+ : sprintf(szextaddr, "%u.%u.%u.%u", NIPQUAD(newip));
|
|
|
-+ DEBUGP("stunaddr=%s (%s)\n", szextaddr, (extip?"forced":"auto"));
|
|
|
-+
|
|
|
-+ rbuf1len = rbufalen = 0;
|
|
|
-+ switch (prtspexp->pbtype)
|
|
|
-+ {
|
|
|
-+ case pb_single:
|
|
|
-+ for (loport = prtspexp->loport; loport != 0; loport++) /* XXX: improper wrap? */
|
|
|
-+ {
|
|
|
-+ t->dst.u.udp.port = htons(loport);
|
|
|
-+ if (nf_ct_expect_related(exp) == 0)
|
|
|
-+ {
|
|
|
-+ DEBUGP("using port %hu\n", loport);
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ if (loport != 0)
|
|
|
-+ {
|
|
|
-+ rbuf1len = sprintf(rbuf1, "%hu", loport);
|
|
|
-+ rbufalen = sprintf(rbufa, "%hu", loport);
|
|
|
-+ }
|
|
|
-+ break;
|
|
|
-+ case pb_range:
|
|
|
-+ for (loport = prtspexp->loport; loport != 0; loport += 2) /* XXX: improper wrap? */
|
|
|
-+ {
|
|
|
-+ t->dst.u.udp.port = htons(loport);
|
|
|
-+ if (nf_ct_expect_related(exp) == 0)
|
|
|
-+ {
|
|
|
-+ hiport = loport + ~exp->mask.src.u.udp.port;
|
|
|
-+ DEBUGP("using ports %hu-%hu\n", loport, hiport);
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ if (loport != 0)
|
|
|
-+ {
|
|
|
-+ rbuf1len = sprintf(rbuf1, "%hu", loport);
|
|
|
-+ rbufalen = sprintf(rbufa, "%hu-%hu", loport, loport+1);
|
|
|
-+ }
|
|
|
-+ break;
|
|
|
-+ case pb_discon:
|
|
|
-+ for (loport = prtspexp->loport; loport != 0; loport++) /* XXX: improper wrap? */
|
|
|
-+ {
|
|
|
-+ t->dst.u.udp.port = htons(loport);
|
|
|
-+ if (nf_ct_expect_related(exp) == 0)
|
|
|
-+ {
|
|
|
-+ DEBUGP("using port %hu (1 of 2)\n", loport);
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ for (hiport = prtspexp->hiport; hiport != 0; hiport++) /* XXX: improper wrap? */
|
|
|
-+ {
|
|
|
-+ t->dst.u.udp.port = htons(hiport);
|
|
|
-+ if (nf_ct_expect_related(exp) == 0)
|
|
|
-+ {
|
|
|
-+ DEBUGP("using port %hu (2 of 2)\n", hiport);
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ if (loport != 0 && hiport != 0)
|
|
|
-+ {
|
|
|
-+ rbuf1len = sprintf(rbuf1, "%hu", loport);
|
|
|
-+ if (hiport == loport+1)
|
|
|
-+ {
|
|
|
-+ rbufalen = sprintf(rbufa, "%hu-%hu", loport, hiport);
|
|
|
-+ }
|
|
|
-+ else
|
|
|
-+ {
|
|
|
-+ rbufalen = sprintf(rbufa, "%hu/%hu", loport, hiport);
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ if (rbuf1len == 0)
|
|
|
-+ {
|
|
|
-+ return 0; /* cannot get replacement port(s) */
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ /* Transport: tran;field;field=val,tran;field;field=val,... */
|
|
|
-+ while (off < tranlen)
|
|
|
-+ {
|
|
|
-+ uint saveoff;
|
|
|
-+ const char* pparamend;
|
|
|
-+ uint nextparamoff;
|
|
|
-+
|
|
|
-+ pparamend = memchr(ptran+off, ',', tranlen-off);
|
|
|
-+ pparamend = (pparamend == NULL) ? ptran+tranlen : pparamend+1;
|
|
|
-+ nextparamoff = pparamend-ptcp;
|
|
|
-+
|
|
|
-+ /*
|
|
|
-+ * We pass over each param twice. On the first pass, we look for a
|
|
|
-+ * destination= field. It is handled by the security policy. If it
|
|
|
-+ * is present, allowed, and equal to our external address, we assume
|
|
|
-+ * that STUN is being used and we leave the client_port= field alone.
|
|
|
-+ */
|
|
|
-+ is_stun = 0;
|
|
|
-+ saveoff = off;
|
|
|
-+ while (off < nextparamoff)
|
|
|
-+ {
|
|
|
-+ const char* pfieldend;
|
|
|
-+ uint nextfieldoff;
|
|
|
-+
|
|
|
-+ pfieldend = memchr(ptran+off, ';', nextparamoff-off);
|
|
|
-+ nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
|
|
|
-+
|
|
|
-+ if (dstact != DSTACT_NONE && strncmp(ptran+off, "destination=", 12) == 0)
|
|
|
-+ {
|
|
|
-+ if (strncmp(ptran+off+12, szextaddr, extaddrlen) == 0)
|
|
|
-+ {
|
|
|
-+ is_stun = 1;
|
|
|
-+ }
|
|
|
-+ if (dstact == DSTACT_STRIP || (dstact == DSTACT_AUTO && !is_stun))
|
|
|
-+ {
|
|
|
-+ diff = nextfieldoff-off;
|
|
|
-+ if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
|
|
|
-+ off, diff, NULL, 0))
|
|
|
-+ {
|
|
|
-+ /* mangle failed, all we can do is bail */
|
|
|
-+ nf_ct_unexpect_related(exp);
|
|
|
-+ return 0;
|
|
|
-+ }
|
|
|
-+ get_skb_tcpdata(skb, &ptcp, &tcplen);
|
|
|
-+ ptran = ptcp+tranoff;
|
|
|
-+ tranlen -= diff;
|
|
|
-+ nextparamoff -= diff;
|
|
|
-+ nextfieldoff -= diff;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ off = nextfieldoff;
|
|
|
-+ }
|
|
|
-+ if (is_stun)
|
|
|
-+ {
|
|
|
-+ continue;
|
|
|
-+ }
|
|
|
-+ off = saveoff;
|
|
|
-+ while (off < nextparamoff)
|
|
|
-+ {
|
|
|
-+ const char* pfieldend;
|
|
|
-+ uint nextfieldoff;
|
|
|
-+
|
|
|
-+ pfieldend = memchr(ptran+off, ';', nextparamoff-off);
|
|
|
-+ nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
|
|
|
-+
|
|
|
-+ if (strncmp(ptran+off, "client_port=", 12) == 0)
|
|
|
-+ {
|
|
|
-+ u_int16_t port;
|
|
|
-+ uint numlen;
|
|
|
-+ uint origoff;
|
|
|
-+ uint origlen;
|
|
|
-+ char* rbuf = rbuf1;
|
|
|
-+ uint rbuflen = rbuf1len;
|
|
|
-+
|
|
|
-+ off += 12;
|
|
|
-+ origoff = (ptran-ptcp)+off;
|
|
|
-+ origlen = 0;
|
|
|
-+ numlen = nf_strtou16(ptran+off, &port);
|
|
|
-+ off += numlen;
|
|
|
-+ origlen += numlen;
|
|
|
-+ if (port != prtspexp->loport)
|
|
|
-+ {
|
|
|
-+ DEBUGP("multiple ports found, port %hu ignored\n", port);
|
|
|
-+ }
|
|
|
-+ else
|
|
|
-+ {
|
|
|
-+ if (ptran[off] == '-' || ptran[off] == '/')
|
|
|
-+ {
|
|
|
-+ off++;
|
|
|
-+ origlen++;
|
|
|
-+ numlen = nf_strtou16(ptran+off, &port);
|
|
|
-+ off += numlen;
|
|
|
-+ origlen += numlen;
|
|
|
-+ rbuf = rbufa;
|
|
|
-+ rbuflen = rbufalen;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ /*
|
|
|
-+ * note we cannot just memcpy() if the sizes are the same.
|
|
|
-+ * the mangle function does skb resizing, checks for a
|
|
|
-+ * cloned skb, and updates the checksums.
|
|
|
-+ *
|
|
|
-+ * parameter 4 below is offset from start of tcp data.
|
|
|
-+ */
|
|
|
-+ diff = origlen-rbuflen;
|
|
|
-+ if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
|
|
|
-+ origoff, origlen, rbuf, rbuflen))
|
|
|
-+ {
|
|
|
-+ /* mangle failed, all we can do is bail */
|
|
|
-+ nf_ct_unexpect_related(exp);
|
|
|
-+ return 0;
|
|
|
-+ }
|
|
|
-+ get_skb_tcpdata(skb, &ptcp, &tcplen);
|
|
|
-+ ptran = ptcp+tranoff;
|
|
|
-+ tranlen -= diff;
|
|
|
-+ nextparamoff -= diff;
|
|
|
-+ nextfieldoff -= diff;
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ off = nextfieldoff;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ off = nextparamoff;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ return 1;
|
|
|
-+}
|
|
|
-+
|
|
|
-+static uint
|
|
|
-+help_out(struct sk_buff *skb, enum ip_conntrack_info ctinfo,
|
|
|
-+ unsigned int matchoff, unsigned int matchlen, struct ip_ct_rtsp_expect* prtspexp,
|
|
|
-+ struct nf_conntrack_expect* exp)
|
|
|
-+{
|
|
|
-+ char* ptcp;
|
|
|
-+ uint tcplen;
|
|
|
-+ uint hdrsoff;
|
|
|
-+ uint hdrslen;
|
|
|
-+ uint lineoff;
|
|
|
-+ uint linelen;
|
|
|
-+ uint off;
|
|
|
-+
|
|
|
-+ //struct iphdr* iph = (struct iphdr*)skb->nh.iph;
|
|
|
-+ //struct tcphdr* tcph = (struct tcphdr*)((void*)iph + iph->ihl*4);
|
|
|
-+
|
|
|
-+ get_skb_tcpdata(skb, &ptcp, &tcplen);
|
|
|
-+ hdrsoff = matchoff;//exp->seq - ntohl(tcph->seq);
|
|
|
-+ hdrslen = matchlen;
|
|
|
-+ off = hdrsoff;
|
|
|
-+ DEBUGP("NAT rtsp help_out\n");
|
|
|
-+
|
|
|
-+ while (nf_mime_nextline(ptcp, hdrsoff+hdrslen, &off, &lineoff, &linelen))
|
|
|
-+ {
|
|
|
-+ if (linelen == 0)
|
|
|
-+ {
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ if (off > hdrsoff+hdrslen)
|
|
|
-+ {
|
|
|
-+ INFOP("!! overrun !!");
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ DEBUGP("hdr: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
|
|
|
-+
|
|
|
-+ if (nf_strncasecmp(ptcp+lineoff, "Transport:", 10) == 0)
|
|
|
-+ {
|
|
|
-+ uint oldtcplen = tcplen;
|
|
|
-+ DEBUGP("hdr: Transport\n");
|
|
|
-+ if (!rtsp_mangle_tran(ctinfo, exp, prtspexp, skb, lineoff, linelen))
|
|
|
-+ {
|
|
|
-+ DEBUGP("hdr: Transport mangle failed");
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ get_skb_tcpdata(skb, &ptcp, &tcplen);
|
|
|
-+ hdrslen -= (oldtcplen-tcplen);
|
|
|
-+ off -= (oldtcplen-tcplen);
|
|
|
-+ lineoff -= (oldtcplen-tcplen);
|
|
|
-+ linelen -= (oldtcplen-tcplen);
|
|
|
-+ DEBUGP("rep: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
|
|
|
-+ }
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ return NF_ACCEPT;
|
|
|
-+}
|
|
|
-+
|
|
|
-+static unsigned int
|
|
|
-+help(struct sk_buff *skb, enum ip_conntrack_info ctinfo,
|
|
|
-+ unsigned int matchoff, unsigned int matchlen, struct ip_ct_rtsp_expect* prtspexp,
|
|
|
-+ struct nf_conntrack_expect* exp)
|
|
|
-+{
|
|
|
-+ int dir = CTINFO2DIR(ctinfo);
|
|
|
-+ int rc = NF_ACCEPT;
|
|
|
-+
|
|
|
-+ switch (dir)
|
|
|
-+ {
|
|
|
-+ case IP_CT_DIR_ORIGINAL:
|
|
|
-+ rc = help_out(skb, ctinfo, matchoff, matchlen, prtspexp, exp);
|
|
|
-+ break;
|
|
|
-+ case IP_CT_DIR_REPLY:
|
|
|
-+ DEBUGP("unmangle ! %u\n", ctinfo);
|
|
|
-+ /* XXX: unmangle */
|
|
|
-+ rc = NF_ACCEPT;
|
|
|
-+ break;
|
|
|
-+ }
|
|
|
-+ //UNLOCK_BH(&ip_rtsp_lock);
|
|
|
-+
|
|
|
-+ return rc;
|
|
|
-+}
|
|
|
-+
|
|
|
-+static void expected(struct nf_conn* ct, struct nf_conntrack_expect *exp)
|
|
|
-+{
|
|
|
-+ struct nf_nat_multi_range_compat mr;
|
|
|
-+ u_int32_t newdstip, newsrcip, newip;
|
|
|
-+
|
|
|
-+ struct nf_conn *master = ct->master;
|
|
|
-+
|
|
|
-+ newdstip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
|
|
|
-+ newsrcip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
|
|
|
-+ //FIXME (how to port that ?)
|
|
|
-+ //code from 2.4 : newip = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) ? newsrcip : newdstip;
|
|
|
-+ newip = newdstip;
|
|
|
-+
|
|
|
-+ DEBUGP("newsrcip=%u.%u.%u.%u, newdstip=%u.%u.%u.%u, newip=%u.%u.%u.%u\n",
|
|
|
-+ NIPQUAD(newsrcip), NIPQUAD(newdstip), NIPQUAD(newip));
|
|
|
-+
|
|
|
-+ mr.rangesize = 1;
|
|
|
-+ // We don't want to manip the per-protocol, just the IPs.
|
|
|
-+ mr.range[0].flags = IP_NAT_RANGE_MAP_IPS;
|
|
|
-+ mr.range[0].min_ip = mr.range[0].max_ip = newip;
|
|
|
-+
|
|
|
-+ nf_nat_setup_info(ct, &mr.range[0], IP_NAT_MANIP_DST);
|
|
|
-+}
|
|
|
-+
|
|
|
-+
|
|
|
-+static void __exit fini(void)
|
|
|
-+{
|
|
|
-+ nf_nat_rtsp_hook = NULL;
|
|
|
-+ nf_nat_rtsp_hook_expectfn = NULL;
|
|
|
-+ synchronize_net();
|
|
|
-+}
|
|
|
-+
|
|
|
-+static int __init init(void)
|
|
|
-+{
|
|
|
-+ printk("nf_nat_rtsp v" IP_NF_RTSP_VERSION " loading\n");
|
|
|
-+
|
|
|
-+ BUG_ON(nf_nat_rtsp_hook);
|
|
|
-+ nf_nat_rtsp_hook = help;
|
|
|
-+ nf_nat_rtsp_hook_expectfn = &expected;
|
|
|
-+
|
|
|
-+ if (stunaddr != NULL)
|
|
|
-+ extip = in_aton(stunaddr);
|
|
|
-+
|
|
|
-+ if (destaction != NULL) {
|
|
|
-+ if (strcmp(destaction, "auto") == 0)
|
|
|
-+ dstact = DSTACT_AUTO;
|
|
|
-+
|
|
|
-+ if (strcmp(destaction, "strip") == 0)
|
|
|
-+ dstact = DSTACT_STRIP;
|
|
|
-+
|
|
|
-+ if (strcmp(destaction, "none") == 0)
|
|
|
-+ dstact = DSTACT_NONE;
|
|
|
-+ }
|
|
|
-+
|
|
|
-+ return 0;
|
|
|
-+}
|
|
|
-+
|
|
|
-+module_init(init);
|
|
|
-+module_exit(fini);
|