#vim 100-netfilter_layer7_2.21.patch
--- /dev/null 2010-02-26 12:46:03.368409969 +0000
+++ 100-netfilter_layer7_2.21.patch 2010-02-26 15:14:35.000000000 +0000
@@ -0,0 +1,2133 @@
+--- /dev/null
++++ b/include/linux/netfilter/xt_layer7.h
+@@ -0,0 +1,13 @@
++#ifndef _XT_LAYER7_H
++#define _XT_LAYER7_H
++
++#define MAX_PATTERN_LEN 8192
++#define MAX_PROTOCOL_LEN 256
++
++struct xt_layer7_info {
++ char protocol[MAX_PROTOCOL_LEN];
++ char pattern[MAX_PATTERN_LEN];
++ u_int8_t invert;
++};
++
++#endif /* _XT_LAYER7_H */
+--- a/include/net/netfilter/nf_conntrack.h
++++ b/include/net/netfilter/nf_conntrack.h
+@@ -116,6 +116,22 @@ struct nf_conn {
+ u_int32_t secmark;
+ #endif
+
++#if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || \
++ defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
++ struct {
++ /*
++ * e.g. "http". NULL before decision. "unknown" after decision
++ * if no match.
++ */
++ char *app_proto;
++ /*
++ * application layer data so far. NULL after match decision.
++ */
++ char *app_data;
++ unsigned int app_data_len;
++ } layer7;
++#endif
++
+ /* Storage reserved for other modules: */
+ union nf_conntrack_proto proto;
+
+--- a/net/netfilter/Kconfig
++++ b/net/netfilter/Kconfig
+@@ -858,6 +858,27 @@ config NETFILTER_XT_MATCH_STATE
+
+ To compile it as a module, choose M here. If unsure, say N.
+
++config NETFILTER_XT_MATCH_LAYER7
++ tristate '"layer7" match support'
++ depends on NETFILTER_XTABLES
++ depends on EXPERIMENTAL && (IP_NF_CONNTRACK || NF_CONNTRACK)
++ depends on NF_CT_ACCT
++ help
++ Say Y if you want to be able to classify connections (and their
++ packets) based on regular expression matching of their application
++ layer data. This is one way to classify applications such as
++ peer-to-peer filesharing systems that do not always use the same
++ port.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
++config NETFILTER_XT_MATCH_LAYER7_DEBUG
++ bool 'Layer 7 debugging output'
++ depends on NETFILTER_XT_MATCH_LAYER7
++ help
++ Say Y to get lots of debugging output.
++
++
+ config NETFILTER_XT_MATCH_STATISTIC
+ tristate '"statistic" match support'
+ depends on NETFILTER_ADVANCED
+--- a/net/netfilter/Makefile
++++ b/net/netfilter/Makefile
+@@ -89,6 +89,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_RECENT)
+ obj-$(CONFIG_NETFILTER_XT_MATCH_SCTP) += xt_sctp.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_SOCKET) += xt_socket.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_STATE) += xt_state.o
++obj-$(CONFIG_NETFILTER_XT_MATCH_LAYER7) += xt_layer7.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_STATISTIC) += xt_statistic.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_STRING) += xt_string.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_TCPMSS) += xt_tcpmss.o
+--- a/net/netfilter/nf_conntrack_core.c
++++ b/net/netfilter/nf_conntrack_core.c
+@@ -201,6 +201,14 @@ destroy_conntrack(struct nf_conntrack *n
+ * too. */
+ nf_ct_remove_expectations(ct);
+
++ #if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
++ if(ct->layer7.app_proto)
++ kfree(ct->layer7.app_proto);
++ if(ct->layer7.app_data)
++ kfree(ct->layer7.app_data);
++ #endif
++
++
+ /* We overload first tuple to link into unconfirmed list. */
+ if (!nf_ct_is_confirmed(ct)) {
+ BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode));
+--- a/net/netfilter/nf_conntrack_standalone.c
++++ b/net/netfilter/nf_conntrack_standalone.c
+@@ -171,6 +171,12 @@ static int ct_seq_show(struct seq_file *
+ goto release;
+ #endif
+
++#if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
++ if(ct->layer7.app_proto &&
++ seq_printf(s, "l7proto=%s ", ct->layer7.app_proto))
++ return -ENOSPC;
++#endif
++
+ if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use)))
+ goto release;
+
+--- /dev/null
++++ b/net/netfilter/regexp/regexp.c
+@@ -0,0 +1,1197 @@
++/*
++ * regcomp and regexec -- regsub and regerror are elsewhere
++ * @(#)regexp.c 1.3 of 18 April 87
++ *
++ * Copyright (c) 1986 by University of Toronto.
++ * Written by Henry Spencer. Not derived from licensed software.
++ *
++ * Permission is granted to anyone to use this software for any
++ * purpose on any computer system, and to redistribute it freely,
++ * subject to the following restrictions:
++ *
++ * 1. The author is not responsible for the consequences of use of
++ * this software, no matter how awful, even if they arise
++ * from defects in it.
++ *
++ * 2. The origin of this software must not be misrepresented, either
++ * by explicit claim or by omission.
++ *
++ * 3. Altered versions must be plainly marked as such, and must not
++ * be misrepresented as being the original software.
++ *
++ * Beware that some of this code is subtly aware of the way operator
++ * precedence is structured in regular expressions. Serious changes in
++ * regular-expression syntax might require a total rethink.
++ *
++ * This code was modified by Ethan Sommer to work within the kernel
++ * (it now uses kmalloc etc..)
++ *
++ * Modified slightly by Matthew Strait to use more modern C.
++ */
++
++#include "regexp.h"
++#include "regmagic.h"
++
++/* added by ethan and matt. Lets it work in both kernel and user space.
++(So iptables can use it, for instance.) Yea, it goes both ways... */
++#if __KERNEL__
++ #define malloc(foo) kmalloc(foo,GFP_ATOMIC)
++#else
++ #define printk(format,args...) printf(format,##args)
++#endif
++
++void regerror(char * s)
++{
++ printk("<3>Regexp: %s\n", s);
++ /* NOTREACHED */
++}
++
++/*
++ * The "internal use only" fields in regexp.h are present to pass info from
++ * compile to execute that permits the execute phase to run lots faster on
++ * simple cases. They are:
++ *
++ * regstart char that must begin a match; '\0' if none obvious
++ * reganch is the match anchored (at beginning-of-line only)?
++ * regmust string (pointer into program) that match must include, or NULL
++ * regmlen length of regmust string
++ *
++ * Regstart and reganch permit very fast decisions on suitable starting points
++ * for a match, cutting down the work a lot. Regmust permits fast rejection
++ * of lines that cannot possibly match. The regmust tests are costly enough
++ * that regcomp() supplies a regmust only if the r.e. contains something
++ * potentially expensive (at present, the only such thing detected is * or +
++ * at the start of the r.e., which can involve a lot of backup). Regmlen is
++ * supplied because the test in regexec() needs it and regcomp() is computing
++ * it anyway.
++ */
++
++/*
++ * Structure for regexp "program". This is essentially a linear encoding
++ * of a nondeterministic finite-state machine (aka syntax charts or
++ * "railroad normal form" in parsing technology). Each node is an opcode
++ * plus a "next" pointer, possibly plus an operand. "Next" pointers of
++ * all nodes except BRANCH implement concatenation; a "next" pointer with
++ * a BRANCH on both ends of it is connecting two alternatives. (Here we
++ * have one of the subtle syntax dependencies: an individual BRANCH (as
++ * opposed to a collection of them) is never concatenated with anything
++ * because of operator precedence.) The operand of some types of node is
++ * a literal string; for others, it is a node leading into a sub-FSM. In
++ * particular, the operand of a BRANCH node is the first node of the branch.
++ * (NB this is *not* a tree structure: the tail of the branch connects
++ * to the thing following the set of BRANCHes.) The opcodes are:
++ */
++
++/* definition number opnd? meaning */
++#define END 0 /* no End of program. */
++#define BOL 1 /* no Match "" at beginning of line. */
++#define EOL 2 /* no Match "" at end of line. */
++#define ANY 3 /* no Match any one character. */
++#define ANYOF 4 /* str Match any character in this string. */
++#define ANYBUT 5 /* str Match any character not in this string. */
++#define BRANCH 6 /* node Match this alternative, or the next... */
++#define BACK 7 /* no Match "", "next" ptr points backward. */
++#define EXACTLY 8 /* str Match this string. */
++#define NOTHING 9 /* no Match empty string. */
++#define STAR 10 /* node Match this (simple) thing 0 or more times. */
++#define PLUS 11 /* node Match this (simple) thing 1 or more times. */
++#define OPEN 20 /* no Mark this point in input as start of #n. */
++ /* OPEN+1 is number 1, etc. */
++#define CLOSE 30 /* no Analogous to OPEN. */
++
++/*
++ * Opcode notes:
++ *
++ * BRANCH The set of branches constituting a single choice are hooked
++ * together with their "next" pointers, since precedence prevents
++ * anything being concatenated to any individual branch. The
++ * "next" pointer of the last BRANCH in a choice points to the
++ * thing following the whole choice. This is also where the
++ * final "next" pointer of each individual branch points; each
++ * branch starts with the operand node of a BRANCH node.
++ *
++ * BACK Normal "next" pointers all implicitly point forward; BACK
++ * exists to make loop structures possible.
++ *
++ * STAR,PLUS '?', and complex '*' and '+', are implemented as circular
++ * BRANCH structures using BACK. Simple cases (one character
++ * per match) are implemented with STAR and PLUS for speed
++ * and to minimize recursive plunges.
++ *
++ * OPEN,CLOSE ...are numbered at compile time.
++ */
++
++/*
++ * A node is one char of opcode followed by two chars of "next" pointer.
++ * "Next" pointers are stored as two 8-bit pieces, high order first. The
++ * value is a positive offset from the opcode of the node containing it.
++ * An operand, if any, simply follows the node. (Note that much of the
++ * code generation knows about this implicit relationship.)
++ *
++ * Using two bytes for the "next" pointer is vast overkill for most things,
++ * but allows patterns to get big without disasters.
++ */
++#define OP(p) (*(p))
++#define NEXT(p) (((*((p)+1)&0377)<<8) + (*((p)+2)&0377))
++#define OPERAND(p) ((p) + 3)
++
++/*
++ * See regmagic.h for one further detail of program structure.
++ */
++
++
++/*
++ * Utility definitions.
++ */
++#ifndef CHARBITS
++#define UCHARAT(p) ((int)*(unsigned char *)(p))
++#else
++#define UCHARAT(p) ((int)*(p)&CHARBITS)
++#endif
++
++#define FAIL(m) { regerror(m); return(NULL); }
++#define ISMULT(c) ((c) == '*' || (c) == '+' || (c) == '?')
++#define META "^$.[()|?+*\\"
++
++/*
++ * Flags to be passed up and down.
++ */
++#define HASWIDTH 01 /* Known never to match null string. */
++#define SIMPLE 02 /* Simple enough to be STAR/PLUS operand. */
++#define SPSTART 04 /* Starts with * or +. */
++#define WORST 0 /* Worst case. */
++
++/*
++ * Global work variables for regcomp().
++ */
++struct match_globals {
++char *reginput; /* String-input pointer. */
++char *regbol; /* Beginning of input, for ^ check. */
++char **regstartp; /* Pointer to startp array. */
++char **regendp; /* Ditto for endp. */
++char *regparse; /* Input-scan pointer. */
++int regnpar; /* () count. */
++char regdummy;
++char *regcode; /* Code-emit pointer; ®dummy = don't. */
++long regsize; /* Code size. */
++};
++
++/*
++ * Forward declarations for regcomp()'s friends.
++ */
++#ifndef STATIC
++#define STATIC static
++#endif
++STATIC char *reg(struct match_globals *g, int paren,int *flagp);
++STATIC char *regbranch(struct match_globals *g, int *flagp);
++STATIC char *regpiece(struct match_globals *g, int *flagp);
++STATIC char *regatom(struct match_globals *g, int *flagp);
++STATIC char *regnode(struct match_globals *g, char op);
++STATIC char *regnext(struct match_globals *g, char *p);
++STATIC void regc(struct match_globals *g, char b);
++STATIC void reginsert(struct match_globals *g, char op, char *opnd);
++STATIC void regtail(struct match_globals *g, char *p, char *val);
++STATIC void regoptail(struct match_globals *g, char *p, char *val);
++
++
++__kernel_size_t my_strcspn(const char *s1,const char *s2)
++{
++ char *scan1;
++ char *scan2;
++ int count;
++
++ count = 0;
++ for (scan1 = (char *)s1; *scan1 != '\0'; scan1++) {
++ for (scan2 = (char *)s2; *scan2 != '\0';) /* ++ moved down. */
++ if (*scan1 == *scan2++)
++ return(count);
++ count++;
++ }
++ return(count);
++}
++
++/*
++ - regcomp - compile a regular expression into internal code
++ *
++ * We can't allocate space until we know how big the compiled form will be,
++ * but we can't compile it (and thus know how big it is) until we've got a
++ * place to put the code. So we cheat: we compile it twice, once with code
++ * generation turned off and size counting turned on, and once "for real".
++ * This also means that we don't allocate space until we are sure that the
++ * thing really will compile successfully, and we never have to move the
++ * code and thus invalidate pointers into it. (Note that it has to be in
++ * one piece because free() must be able to free it all.)
++ *
++ * Beware that the optimization-preparation code in here knows about some
++ * of the structure of the compiled regexp.
++ */
++regexp *
++regcomp(char *exp,int *patternsize)
++{
++ register regexp *r;
++ register char *scan;
++ register char *longest;
++ register int len;
++ int flags;
++ struct match_globals g;
++
++ /* commented out by ethan
++ extern char *malloc();
++ */
++
++ if (exp == NULL)
++ FAIL("NULL argument");
++
++ /* First pass: determine size, legality. */
++ g.regparse = exp;
++ g.regnpar = 1;
++ g.regsize = 0L;
++ g.regcode = &g.regdummy;
++ regc(&g, MAGIC);
++ if (reg(&g, 0, &flags) == NULL)
++ return(NULL);
++
++ /* Small enough for pointer-storage convention? */
++ if (g.regsize >= 32767L) /* Probably could be 65535L. */
++ FAIL("regexp too big");
++
++ /* Allocate space. */
++ *patternsize=sizeof(regexp) + (unsigned)g.regsize;
++ r = (regexp *)malloc(sizeof(regexp) + (unsigned)g.regsize);
++ if (r == NULL)
++ FAIL("out of space");
++
++ /* Second pass: emit code. */
++ g.regparse = exp;
++ g.regnpar = 1;
++ g.regcode = r->program;
++ regc(&g, MAGIC);
++ if (reg(&g, 0, &flags) == NULL)
++ return(NULL);
++
++ /* Dig out information for optimizations. */
++ r->regstart = '\0'; /* Worst-case defaults. */
++ r->reganch = 0;
++ r->regmust = NULL;
++ r->regmlen = 0;
++ scan = r->program+1; /* First BRANCH. */
++ if (OP(regnext(&g, scan)) == END) { /* Only one top-level choice. */
++ scan = OPERAND(scan);
++
++ /* Starting-point info. */
++ if (OP(scan) == EXACTLY)
++ r->regstart = *OPERAND(scan);
++ else if (OP(scan) == BOL)
++ r->reganch++;
++
++ /*
++ * If there's something expensive in the r.e., find the
++ * longest literal string that must appear and make it the
++ * regmust. Resolve ties in favor of later strings, since
++ * the regstart check works with the beginning of the r.e.
++ * and avoiding duplication strengthens checking. Not a
++ * strong reason, but sufficient in the absence of others.
++ */
++ if (flags&SPSTART) {
++ longest = NULL;
++ len = 0;
++ for (; scan != NULL; scan = regnext(&g, scan))
++ if (OP(scan) == EXACTLY && strlen(OPERAND(scan)) >= len) {
++ longest = OPERAND(scan);
++ len = strlen(OPERAND(scan));
++ }
++ r->regmust = longest;
++ r->regmlen = len;
++ }
++ }
++
++ return(r);
++}
++
++/*
++ - reg - regular expression, i.e. main body or parenthesized thing
++ *
++ * Caller must absorb opening parenthesis.
++ *
++ * Combining parenthesis handling with the base level of regular expression
++ * is a trifle forced, but the need to tie the tails of the branches to what
++ * follows makes it hard to avoid.
++ */
++static char *
++reg(struct match_globals *g, int paren, int *flagp /* Parenthesized? */ )
++{
++ register char *ret;
++ register char *br;
++ register char *ender;
++ register int parno = 0; /* 0 makes gcc happy */
++ int flags;
++
++ *flagp = HASWIDTH; /* Tentatively. */
++
++ /* Make an OPEN node, if parenthesized. */
++ if (paren) {
++ if (g->regnpar >= NSUBEXP)
++ FAIL("too many ()");
++ parno = g->regnpar;
++ g->regnpar++;
++ ret = regnode(g, OPEN+parno);
++ } else
++ ret = NULL;
++
++ /* Pick up the branches, linking them together. */
++ br = regbranch(g, &flags);
++ if (br == NULL)
++ return(NULL);
++ if (ret != NULL)
++ regtail(g, ret, br); /* OPEN -> first. */
++ else
++ ret = br;
++ if (!(flags&HASWIDTH))
++ *flagp &= ~HASWIDTH;
++ *flagp |= flags&SPSTART;
++ while (*g->regparse == '|') {
++ g->regparse++;
++ br = regbranch(g, &flags);
++ if (br == NULL)
++ return(NULL);
++ regtail(g, ret, br); /* BRANCH -> BRANCH. */
++ if (!(flags&HASWIDTH))
++ *flagp &= ~HASWIDTH;
++ *flagp |= flags&SPSTART;
++ }
++
++ /* Make a closing node, and hook it on the end. */
++ ender = regnode(g, (paren) ? CLOSE+parno : END);
++ regtail(g, ret, ender);
++
++ /* Hook the tails of the branches to the closing node. */
++ for (br = ret; br != NULL; br = regnext(g, br))
++ regoptail(g, br, ender);
++
++ /* Check for proper termination. */
++ if (paren && *g->regparse++ != ')') {
++ FAIL("unmatched ()");
++ } else if (!paren && *g->regparse != '\0') {
++ if (*g->regparse == ')') {
++ FAIL("unmatched ()");
++ } else
++ FAIL("junk on end"); /* "Can't happen". */
++ /* NOTREACHED */
++ }
++
++ return(ret);
++}
++
++/*
++ - regbranch - one alternative of an | operator
++ *
++ * Implements the concatenation operator.
++ */
++static char *
++regbranch(struct match_globals *g, int *flagp)
++{
++ register char *ret;
++ register char *chain;
++ register char *latest;
++ int flags;
++
++ *flagp = WORST; /* Tentatively. */
++
++ ret = regnode(g, BRANCH);
++ chain = NULL;
++ while (*g->regparse != '\0' && *g->regparse != '|' && *g->regparse != ')') {
++ latest = regpiece(g, &flags);
++ if (latest == NULL)
++ return(NULL);
++ *flagp |= flags&HASWIDTH;
++ if (chain == NULL) /* First piece. */
++ *flagp |= flags&SPSTART;
++ else
++ regtail(g, chain, latest);
++ chain = latest;
++ }
++ if (chain == NULL) /* Loop ran zero times. */
++ (void) regnode(g, NOTHING);
++
++ return(ret);
++}
++
++/*
++ - regpiece - something followed by possible [*+?]
++ *
++ * Note that the branching code sequences used for ? and the general cases
++ * of * and + are somewhat optimized: they use the same NOTHING node as
++ * both the endmarker for their branch list and the body of the last branch.
++ * It might seem that this node could be dispensed with entirely, but the
++ * endmarker role is not redundant.
++ */
++static char *
++regpiece(struct match_globals *g, int *flagp)
++{
++ register char *ret;
++ register char op;
++ register char *next;
++ int flags;
++
++ ret = regatom(g, &flags);
++ if (ret == NULL)
++ return(NULL);
++
++ op = *g->regparse;
++ if (!ISMULT(op)) {
++ *flagp = flags;
++ return(ret);
++ }
++
++ if (!(flags&HASWIDTH) && op != '?')
++ FAIL("*+ operand could be empty");
++ *flagp = (op != '+') ? (WORST|SPSTART) : (WORST|HASWIDTH);
++
++ if (op == '*' && (flags&SIMPLE))
++ reginsert(g, STAR, ret);
++ else if (op == '*') {
++ /* Emit x* as (x&|), where & means "self". */
++ reginsert(g, BRANCH, ret); /* Either x */
++ regoptail(g, ret, regnode(g, BACK)); /* and loop */
++ regoptail(g, ret, ret); /* back */
++ regtail(g, ret, regnode(g, BRANCH)); /* or */
++ regtail(g, ret, regnode(g, NOTHING)); /* null. */
++ } else if (op == '+' && (flags&SIMPLE))
++ reginsert(g, PLUS, ret);
++ else if (op == '+') {
++ /* Emit x+ as x(&|), where & means "self". */
++ next = regnode(g, BRANCH); /* Either */
++ regtail(g, ret, next);
++ regtail(g, regnode(g, BACK), ret); /* loop back */
++ regtail(g, next, regnode(g, BRANCH)); /* or */
++ regtail(g, ret, regnode(g, NOTHING)); /* null. */
++ } else if (op == '?') {
++ /* Emit x? as (x|) */
++ reginsert(g, BRANCH, ret); /* Either x */
++ regtail(g, ret, regnode(g, BRANCH)); /* or */
++ next = regnode(g, NOTHING); /* null. */
++ regtail(g, ret, next);
++ regoptail(g, ret, next);
++ }
++ g->regparse++;
++ if (ISMULT(*g->regparse))
++ FAIL("nested *?+");
++
++ return(ret);
++}
++
++/*
++ - regatom - the lowest level
++ *
++ * Optimization: gobbles an entire sequence of ordinary characters so that
++ * it can turn them into a single node, which is smaller to store and
++ * faster to run. Backslashed characters are exceptions, each becoming a
++ * separate node; the code is simpler that way and it's not worth fixing.
++ */
++static char *
++regatom(struct match_globals *g, int *flagp)
++{
++ register char *ret;
++ int flags;
++
++ *flagp = WORST; /* Tentatively. */
++
++ switch (*g->regparse++) {
++ case '^':
++ ret = regnode(g, BOL);
++ break;
++ case '$':
++ ret = regnode(g, EOL);
++ break;
++ case '.':
++ ret = regnode(g, ANY);
++ *flagp |= HASWIDTH|SIMPLE;
++ break;
++ case '[': {
++ register int class;
++ register int classend;
++
++ if (*g->regparse == '^') { /* Complement of range. */
++ ret = regnode(g, ANYBUT);
++ g->regparse++;
++ } else
++ ret = regnode(g, ANYOF);
++ if (*g->regparse == ']' || *g->regparse == '-')
++ regc(g, *g->regparse++);
++ while (*g->regparse != '\0' && *g->regparse != ']') {
++ if (*g->regparse == '-') {
++ g->regparse++;
++ if (*g->regparse == ']' || *g->regparse == '\0')
++ regc(g, '-');
++ else {
++ class = UCHARAT(g->regparse-2)+1;
++ classend = UCHARAT(g->regparse);
++ if (class > classend+1)
++ FAIL("invalid [] range");
++ for (; class <= classend; class++)
++ regc(g, class);
++ g->regparse++;
++ }
++ } else
++ regc(g, *g->regparse++);
++ }
++ regc(g, '\0');
++ if (*g->regparse != ']')
++ FAIL("unmatched []");
++ g->regparse++;
++ *flagp |= HASWIDTH|SIMPLE;
++ }
++ break;
++ case '(':
++ ret = reg(g, 1, &flags);
++ if (ret == NULL)
++ return(NULL);
++ *flagp |= flags&(HASWIDTH|SPSTART);
++ break;
++ case '\0':
++ case '|':
++ case ')':
++ FAIL("internal urp"); /* Supposed to be caught earlier. */
++ break;
++ case '?':
++ case '+':
++ case '*':
++ FAIL("?+* follows nothing");
++ break;
++ case '\\':
++ if (*g->regparse == '\0')
++ FAIL("trailing \\");
++ ret = regnode(g, EXACTLY);
++ regc(g, *g->regparse++);
++ regc(g, '\0');
++ *flagp |= HASWIDTH|SIMPLE;
++ break;
++ default: {
++ register int len;
++ register char ender;
++
++ g->regparse--;
++ len = my_strcspn((const char *)g->regparse, (const char *)META);
++ if (len <= 0)
++ FAIL("internal disaster");
++ ender = *(g->regparse+len);
++ if (len > 1 && ISMULT(ender))
++ len--; /* Back off clear of ?+* operand. */
++ *flagp |= HASWIDTH;
++ if (len == 1)
++ *flagp |= SIMPLE;
++ ret = regnode(g, EXACTLY);
++ while (len > 0) {
++ regc(g, *g->regparse++);
++ len--;
++ }
++ regc(g, '\0');
++ }
++ break;
++ }
++
++ return(ret);
++}
++
++/*
++ - regnode - emit a node
++ */
++static char * /* Location. */
++regnode(struct match_globals *g, char op)
++{
++ register char *ret;
++ register char *ptr;
++
++ ret = g->regcode;
++ if (ret == &g->regdummy) {
++ g->regsize += 3;
++ return(ret);
++ }
++
++ ptr = ret;
++ *ptr++ = op;
++ *ptr++ = '\0'; /* Null "next" pointer. */
++ *ptr++ = '\0';
++ g->regcode = ptr;
++
++ return(ret);
++}
++
++/*
++ - regc - emit (if appropriate) a byte of code
++ */
++static void
++regc(struct match_globals *g, char b)
++{
++ if (g->regcode != &g->regdummy)
++ *g->regcode++ = b;
++ else
++ g->regsize++;
++}
++
++/*
++ - reginsert - insert an operator in front of already-emitted operand
++ *
++ * Means relocating the operand.
++ */
++static void
++reginsert(struct match_globals *g, char op, char* opnd)
++{
++ register char *src;
++ register char *dst;
++ register char *place;
++
++ if (g->regcode == &g->regdummy) {
++ g->regsize += 3;
++ return;
++ }
++
++ src = g->regcode;
++ g->regcode += 3;
++ dst = g->regcode;
++ while (src > opnd)
++ *--dst = *--src;
++
++ place = opnd; /* Op node, where operand used to be. */
++ *place++ = op;
++ *place++ = '\0';
++ *place++ = '\0';
++}
++
++/*
++ - regtail - set the next-pointer at the end of a node chain
++ */
++static void
++regtail(struct match_globals *g, char *p, char *val)
++{
++ register char *scan;
++ register char *temp;
++ register int offset;
++
++ if (p == &g->regdummy)
++ return;
++
++ /* Find last node. */
++ scan = p;
++ for (;;) {
++ temp = regnext(g, scan);
++ if (temp == NULL)
++ break;
++ scan = temp;
++ }
++
++ if (OP(scan) == BACK)
++ offset = scan - val;
++ else
++ offset = val - scan;
++ *(scan+1) = (offset>>8)&0377;
++ *(scan+2) = offset&0377;
++}
++
++/*
++ - regoptail - regtail on operand of first argument; nop if operandless
++ */
++static void
++regoptail(struct match_globals *g, char *p, char *val)
++{
++ /* "Operandless" and "op != BRANCH" are synonymous in practice. */
++ if (p == NULL || p == &g->regdummy || OP(p) != BRANCH)
++ return;
++ regtail(g, OPERAND(p), val);
++}
++
++/*
++ * regexec and friends
++ */
++
++
++/*
++ * Forwards.
++ */
++STATIC int regtry(struct match_globals *g, regexp *prog, char *string);
++STATIC int regmatch(struct match_globals *g, char *prog);
++STATIC int regrepeat(struct match_globals *g, char *p);
++
++#ifdef DEBUG
++int regnarrate = 0;
++void regdump();
++STATIC char *regprop(char *op);
++#endif
++
++/*
++ - regexec - match a regexp against a string
++ */
++int
++regexec(regexp *prog, char *string)
++{
++ register char *s;
++ struct match_globals g;
++
++ /* Be paranoid... */
++ if (prog == NULL || string == NULL) {
++ printk("<3>Regexp: NULL parameter\n");
++ return(0);
++ }
++
++ /* Check validity of program. */
++ if (UCHARAT(prog->program) != MAGIC) {
++ printk("<3>Regexp: corrupted program\n");
++ return(0);
++ }
++
++ /* If there is a "must appear" string, look for it. */
++ if (prog->regmust != NULL) {
++ s = string;
++ while ((s = strchr(s, prog->regmust[0])) != NULL) {
++ if (strncmp(s, prog->regmust, prog->regmlen) == 0)
++ break; /* Found it. */
++ s++;
++ }
++ if (s == NULL) /* Not present. */
++ return(0);
++ }
++
++ /* Mark beginning of line for ^ . */
++ g.regbol = string;
++
++ /* Simplest case: anchored match need be tried only once. */
++ if (prog->reganch)
++ return(regtry(&g, prog, string));
++
++ /* Messy cases: unanchored match. */
++ s = string;
++ if (prog->regstart != '\0')
++ /* We know what char it must start with. */
++ while ((s = strchr(s, prog->regstart)) != NULL) {
++ if (regtry(&g, prog, s))
++ return(1);
++ s++;
++ }
++ else
++ /* We don't -- general case. */
++ do {
++ if (regtry(&g, prog, s))
++ return(1);
++ } while (*s++ != '\0');
++
++ /* Failure. */
++ return(0);
++}
++
++/*
++ - regtry - try match at specific point
++ */
++static int /* 0 failure, 1 success */
++regtry(struct match_globals *g, regexp *prog, char *string)
++{
++ register int i;
++ register char **sp;
++ register char **ep;
++
++ g->reginput = string;
++ g->regstartp = prog->startp;
++ g->regendp = prog->endp;
++
++ sp = prog->startp;
++ ep = prog->endp;
++ for (i = NSUBEXP; i > 0; i--) {
++ *sp++ = NULL;
++ *ep++ = NULL;
++ }
++ if (regmatch(g, prog->program + 1)) {
++ prog->startp[0] = string;
++ prog->endp[0] = g->reginput;
++ return(1);
++ } else
++ return(0);
++}
++
++/*
++ - regmatch - main matching routine
++ *
++ * Conceptually the strategy is simple: check to see whether the current
++ * node matches, call self recursively to see whether the rest matches,
++ * and then act accordingly. In practice we make some effort to avoid
++ * recursion, in particular by going through "ordinary" nodes (that don't
++ * need to know whether the rest of the match failed) by a loop instead of
++ * by recursion.
++ */
++static int /* 0 failure, 1 success */
++regmatch(struct match_globals *g, char *prog)
++{
++ register char *scan = prog; /* Current node. */
++ char *next; /* Next node. */
++
++#ifdef DEBUG
++ if (scan != NULL && regnarrate)
++ fprintf(stderr, "%s(\n", regprop(scan));
++#endif
++ while (scan != NULL) {
++#ifdef DEBUG
++ if (regnarrate)
++ fprintf(stderr, "%s...\n", regprop(scan));
++#endif
++ next = regnext(g, scan);
++
++ switch (OP(scan)) {
++ case BOL:
++ if (g->reginput != g->regbol)
++ return(0);
++ break;
++ case EOL:
++ if (*g->reginput != '\0')
++ return(0);
++ break;
++ case ANY:
++ if (*g->reginput == '\0')
++ return(0);
++ g->reginput++;
++ break;
++ case EXACTLY: {
++ register int len;
++ register char *opnd;
++
++ opnd = OPERAND(scan);
++ /* Inline the first character, for speed. */
++ if (*opnd != *g->reginput)
++ return(0);
++ len = strlen(opnd);
++ if (len > 1 && strncmp(opnd, g->reginput, len) != 0)
++ return(0);
++ g->reginput += len;
++ }
++ break;
++ case ANYOF:
++ if (*g->reginput == '\0' || strchr(OPERAND(scan), *g->reginput) == NULL)
++ return(0);
++ g->reginput++;
++ break;
++ case ANYBUT:
++ if (*g->reginput == '\0' || strchr(OPERAND(scan), *g->reginput) != NULL)
++ return(0);
++ g->reginput++;
++ break;
++ case NOTHING:
++ case BACK:
++ break;
++ case OPEN+1:
++ case OPEN+2:
++ case OPEN+3:
++ case OPEN+4:
++ case OPEN+5:
++ case OPEN+6:
++ case OPEN+7:
++ case OPEN+8:
++ case OPEN+9: {
++ register int no;
++ register char *save;
++
++ no = OP(scan) - OPEN;
++ save = g->reginput;
++
++ if (regmatch(g, next)) {
++ /*
++ * Don't set startp if some later
++ * invocation of the same parentheses
++ * already has.
++ */
++ if (g->regstartp[no] == NULL)
++ g->regstartp[no] = save;
++ return(1);
++ } else
++ return(0);
++ }
++ break;
++ case CLOSE+1:
++ case CLOSE+2:
++ case CLOSE+3:
++ case CLOSE+4:
++ case CLOSE+5:
++ case CLOSE+6:
++ case CLOSE+7:
++ case CLOSE+8:
++ case CLOSE+9:
++ {
++ register int no;
++ register char *save;
++
++ no = OP(scan) - CLOSE;
++ save = g->reginput;
++
++ if (regmatch(g, next)) {
++ /*
++ * Don't set endp if some later
++ * invocation of the same parentheses
++ * already has.
++ */
++ if (g->regendp[no] == NULL)
++ g->regendp[no] = save;
++ return(1);
++ } else
++ return(0);
++ }
++ break;
++ case BRANCH: {
++ register char *save;
++
++ if (OP(next) != BRANCH) /* No choice. */
++ next = OPERAND(scan); /* Avoid recursion. */
++ else {
++ do {
++ save = g->reginput;
++ if (regmatch(g, OPERAND(scan)))
++ return(1);
++ g->reginput = save;
++ scan = regnext(g, scan);
++ } while (scan != NULL && OP(scan) == BRANCH);
++ return(0);
++ /* NOTREACHED */
++ }
++ }
++ break;
++ case STAR:
++ case PLUS: {
++ register char nextch;
++ register int no;
++ register char *save;
++ register int min;
++
++ /*
++ * Lookahead to avoid useless match attempts
++ * when we know what character comes next.
++ */
++ nextch = '\0';
++ if (OP(next) == EXACTLY)
++ nextch = *OPERAND(next);
++ min = (OP(scan) == STAR) ? 0 : 1;
++ save = g->reginput;
++ no = regrepeat(g, OPERAND(scan));
++ while (no >= min) {
++ /* If it could work, try it. */
++ if (nextch == '\0' || *g->reginput == nextch)
++ if (regmatch(g, next))
++ return(1);
++ /* Couldn't or didn't -- back up. */
++ no--;
++ g->reginput = save + no;
++ }
++ return(0);
++ }
++ break;
++ case END:
++ return(1); /* Success! */
++ break;
++ default:
++ printk("<3>Regexp: memory corruption\n");
++ return(0);
++ break;
++ }
++
++ scan = next;
++ }
++
++ /*
++ * We get here only if there's trouble -- normally "case END" is
++ * the terminating point.
++ */
++ printk("<3>Regexp: corrupted pointers\n");
++ return(0);
++}
++
++/*
++ - regrepeat - repeatedly match something simple, report how many
++ */
++static int
++regrepeat(struct match_globals *g, char *p)
++{
++ register int count = 0;
++ register char *scan;
++ register char *opnd;
++
++ scan = g->reginput;
++ opnd = OPERAND(p);
++ switch (OP(p)) {
++ case ANY:
++ count = strlen(scan);
++ scan += count;
++ break;
++ case EXACTLY:
++ while (*opnd == *scan) {
++ count++;
++ scan++;
++ }
++ break;
++ case ANYOF:
++ while (*scan != '\0' && strchr(opnd, *scan) != NULL) {
++ count++;
++ scan++;
++ }
++ break;
++ case ANYBUT:
++ while (*scan != '\0' && strchr(opnd, *scan) == NULL) {
++ count++;
++ scan++;
++ }
++ break;
++ default: /* Oh dear. Called inappropriately. */
++ printk("<3>Regexp: internal foulup\n");
++ count = 0; /* Best compromise. */
++ break;
++ }
++ g->reginput = scan;
++
++ return(count);
++}
++
++/*
++ - regnext - dig the "next" pointer out of a node
++ */
++static char*
++regnext(struct match_globals *g, char *p)
++{
++ register int offset;
++
++ if (p == &g->regdummy)
++ return(NULL);
++
++ offset = NEXT(p);
++ if (offset == 0)
++ return(NULL);
++
++ if (OP(p) == BACK)
++ return(p-offset);
++ else
++ return(p+offset);
++}
++
++#ifdef DEBUG
++
++STATIC char *regprop();
++
++/*
++ - regdump - dump a regexp onto stdout in vaguely comprehensible form
++ */
++void
++regdump(regexp *r)
++{
++ register char *s;
++ register char op = EXACTLY; /* Arbitrary non-END op. */
++ register char *next;
++ /* extern char *strchr(); */
++
++
++ s = r->program + 1;
++ while (op != END) { /* While that wasn't END last time... */
++ op = OP(s);
++ printf("%2d%s", s-r->program, regprop(s)); /* Where, what. */
++ next = regnext(s);
++ if (next == NULL) /* Next ptr. */
++ printf("(0)");
++ else
++ printf("(%d)", (s-r->program)+(next-s));
++ s += 3;
++ if (op == ANYOF || op == ANYBUT || op == EXACTLY) {
++ /* Literal string, where present. */
++ while (*s != '\0') {
++ putchar(*s);
++ s++;
++ }
++ s++;
++ }
++ putchar('\n');
++ }
++
++ /* Header fields of interest. */
++ if (r->regstart != '\0')
++ printf("start `%c' ", r->regstart);
++ if (r->reganch)
++ printf("anchored ");
++ if (r->regmust != NULL)
++ printf("must have \"%s\"", r->regmust);
++ printf("\n");
++}
++
++/*
++ - regprop - printable representation of opcode
++ */
++static char *
++regprop(char *op)
++{
++#define BUFLEN 50
++ register char *p;
++ static char buf[BUFLEN];
++
++ strcpy(buf, ":");
++
++ switch (OP(op)) {
++ case BOL:
++ p = "BOL";
++ break;
++ case EOL:
++ p = "EOL";
++ break;
++ case ANY:
++ p = "ANY";
++ break;
++ case ANYOF:
++ p = "ANYOF";
++ break;
++ case ANYBUT:
++ p = "ANYBUT";
++ break;
++ case BRANCH:
++ p = "BRANCH";
++ break;
++ case EXACTLY:
++ p = "EXACTLY";
++ break;
++ case NOTHING:
++ p = "NOTHING";
++ break;
++ case BACK:
++ p = "BACK";
++ break;
++ case END:
++ p = "END";
++ break;
++ case OPEN+1:
++ case OPEN+2:
++ case OPEN+3:
++ case OPEN+4:
++ case OPEN+5:
++ case OPEN+6:
++ case OPEN+7:
++ case OPEN+8:
++ case OPEN+9:
++ snprintf(buf+strlen(buf),BUFLEN-strlen(buf), "OPEN%d", OP(op)-OPEN);
++ p = NULL;
++ break;
++ case CLOSE+1:
++ case CLOSE+2:
++ case CLOSE+3:
++ case CLOSE+4:
++ case CLOSE+5:
++ case CLOSE+6:
++ case CLOSE+7:
++ case CLOSE+8:
++ case CLOSE+9:
++ snprintf(buf+strlen(buf),BUFLEN-strlen(buf), "CLOSE%d", OP(op)-CLOSE);
++ p = NULL;
++ break;
++ case STAR:
++ p = "STAR";
++ break;
++ case PLUS:
++ p = "PLUS";
++ break;
++ default:
++ printk("<3>Regexp: corrupted opcode\n");
++ break;
++ }
++ if (p != NULL)
++ strncat(buf, p, BUFLEN-strlen(buf));
++ return(buf);
++}
++#endif
++
++
+--- /dev/null
++++ b/net/netfilter/regexp/regexp.h
+@@ -0,0 +1,41 @@
++/*
++ * Definitions etc. for regexp(3) routines.
++ *
++ * Caveat: this is V8 regexp(3) [actually, a reimplementation thereof],
++ * not the System V one.
++ */
++
++#ifndef REGEXP_H
++#define REGEXP_H
++
++
++/*
++http://www.opensource.apple.com/darwinsource/10.3/expect-1/expect/expect.h ,
++which contains a version of this library, says:
++
++ *
++ * NSUBEXP must be at least 10, and no greater than 117 or the parser
++ * will not work properly.
++ *
++
++However, it looks rather like this library is limited to 10. If you think
++otherwise, let us know.
++*/
++
++#define NSUBEXP 10
++typedef struct regexp {
++ char *startp[NSUBEXP];
++ char *endp[NSUBEXP];
++ char regstart; /* Internal use only. */
++ char reganch; /* Internal use only. */
++ char *regmust; /* Internal use only. */
++ int regmlen; /* Internal use only. */
++ char program[1]; /* Unwarranted chumminess with compiler. */
++} regexp;
++
++regexp * regcomp(char *exp, int *patternsize);
++int regexec(regexp *prog, char *string);
++void regsub(regexp *prog, char *source, char *dest);
++void regerror(char *s);
++
++#endif
+--- /dev/null
++++ b/net/netfilter/regexp/regmagic.h
+@@ -0,0 +1,5 @@
++/*
++ * The first byte of the regexp internal "program" is actually this magic
++ * number; the start node begins in the second byte.
++ */
++#define MAGIC 0234
+--- /dev/null
++++ b/net/netfilter/regexp/regsub.c
+@@ -0,0 +1,95 @@
++/*
++ * regsub
++ * @(#)regsub.c 1.3 of 2 April 86
++ *
++ * Copyright (c) 1986 by University of Toronto.
++ * Written by Henry Spencer. Not derived from licensed software.
++ *
++ * Permission is granted to anyone to use this software for any
++ * purpose on any computer system, and to redistribute it freely,
++ * subject to the following restrictions:
++ *
++ * 1. The author is not responsible for the consequences of use of
++ * this software, no matter how awful, even if they arise
++ * from defects in it.
++ *
++ * 2. The origin of this software must not be misrepresented, either
++ * by explicit claim or by omission.
++ *
++ * 3. Altered versions must be plainly marked as such, and must not
++ * be misrepresented as being the original software.
++ *
++ *
++ * This code was modified by Ethan Sommer to work within the kernel
++ * (it now uses kmalloc etc..)
++ *
++ */
++#include "regexp.h"
++#include "regmagic.h"
++#include <linux/string.h>
++
++
++#ifndef CHARBITS
++#define UCHARAT(p) ((int)*(unsigned char *)(p))
++#else
++#define UCHARAT(p) ((int)*(p)&CHARBITS)
++#endif
++
++#if 0
++//void regerror(char * s)
++//{
++// printk("regexp(3): %s", s);
++// /* NOTREACHED */
++//}
++#endif
++
++/*
++ - regsub - perform substitutions after a regexp match
++ */
++void
++regsub(regexp * prog, char * source, char * dest)
++{
++ register char *src;
++ register char *dst;
++ register char c;
++ register int no;
++ register int len;
++
++ /* Not necessary and gcc doesn't like it -MLS */
++ /*extern char *strncpy();*/
++
++ if (prog == NULL || source == NULL || dest == NULL) {
++ regerror("NULL parm to regsub");
++ return;
++ }
++ if (UCHARAT(prog->program) != MAGIC) {
++ regerror("damaged regexp fed to regsub");
++ return;
++ }
++
++ src = source;
++ dst = dest;
++ while ((c = *src++) != '\0') {
++ if (c == '&')
++ no = 0;
++ else if (c == '\\' && '0' <= *src && *src <= '9')
++ no = *src++ - '0';
++ else
++ no = -1;
++
++ if (no < 0) { /* Ordinary character. */
++ if (c == '\\' && (*src == '\\' || *src == '&'))
++ c = *src++;
++ *dst++ = c;
++ } else if (prog->startp[no] != NULL && prog->endp[no] != NULL) {
++ len = prog->endp[no] - prog->startp[no];
++ (void) strncpy(dst, prog->startp[no], len);
++ dst += len;
++ if (len != 0 && *(dst-1) == '\0') { /* strncpy hit NUL. */
++ regerror("damaged match string");
++ return;
++ }
++ }
++ }
++ *dst++ = '\0';
++}
+--- /dev/null
++++ b/net/netfilter/xt_layer7.c
+@@ -0,0 +1,666 @@
++/*
++ Kernel module to match application layer (OSI layer 7) data in connections.
++
++ http://l7-filter.sf.net
++
++ (C) 2003-2009 Matthew Strait and Ethan Sommer.
++
++ 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.
++ http://www.gnu.org/licenses/gpl.txt
++
++ Based on ipt_string.c (C) 2000 Emmanuel Roger <winfield@freegates.be>,
++ xt_helper.c (C) 2002 Harald Welte and cls_layer7.c (C) 2003 Matthew Strait,
++ Ethan Sommer, Justin Levandoski.
++*/
++
++#include <linux/spinlock.h>
++#include <linux/version.h>
++#include <net/ip.h>
++#include <net/tcp.h>
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/netfilter.h>
++#include <net/netfilter/nf_conntrack.h>
++#include <net/netfilter/nf_conntrack_core.h>
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 27)
++#include <net/netfilter/nf_conntrack_extend.h>
++#include <net/netfilter/nf_conntrack_acct.h>
++#endif
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_layer7.h>
++#include <linux/ctype.h>
++#include <linux/proc_fs.h>
++
++#include "regexp/regexp.c"
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Matthew Strait <quadong@users.sf.net>, Ethan Sommer <sommere@users.sf.net>");
++MODULE_DESCRIPTION("iptables application layer match module");
++MODULE_ALIAS("ipt_layer7");
++MODULE_VERSION("2.21");
++
++static int maxdatalen = 2048; // this is the default
++module_param(maxdatalen, int, 0444);
++MODULE_PARM_DESC(maxdatalen, "maximum bytes of data looked at by l7-filter");
++#ifdef CONFIG_NETFILTER_XT_MATCH_LAYER7_DEBUG
++ #define DPRINTK(format,args...) printk(format,##args)
++#else
++ #define DPRINTK(format,args...)
++#endif
++
++/* Number of packets whose data we look at.
++This can be modified through /proc/net/layer7_numpackets */
++static int num_packets = 10;
++
++static struct pattern_cache {
++ char * regex_string;
++ regexp * pattern;
++ struct pattern_cache * next;
++} * first_pattern_cache = NULL;
++
++DEFINE_SPINLOCK(l7_lock);
++
++static int total_acct_packets(struct nf_conn *ct)
++{
++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 26)
++ BUG_ON(ct == NULL);
++ return (ct->counters[IP_CT_DIR_ORIGINAL].packets + ct->counters[IP_CT_DIR_REPLY].packets);
++#else
++ struct nf_conn_counter *acct;
++
++ BUG_ON(ct == NULL);
++ acct = nf_conn_acct_find(ct);
++ if (!acct)
++ return 0;
++ return (acct[IP_CT_DIR_ORIGINAL].packets + acct[IP_CT_DIR_REPLY].packets);
++#endif
++}
++
++#ifdef CONFIG_IP_NF_MATCH_LAYER7_DEBUG
++/* Converts an unfriendly string into a friendly one by
++replacing unprintables with periods and all whitespace with " ". */
++static char * friendly_print(unsigned char * s)
++{
++ char * f = kmalloc(strlen(s) + 1, GFP_ATOMIC);
++ int i;
++
++ if(!f) {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "friendly_print, bailing.\n");
++ return NULL;
++ }
++
++ for(i = 0; i < strlen(s); i++){
++ if(isprint(s[i]) && s[i] < 128) f[i] = s[i];
++ else if(isspace(s[i])) f[i] = ' ';
++ else f[i] = '.';
++ }
++ f[i] = '\0';
++ return f;
++}
++
++static char dec2hex(int i)
++{
++ switch (i) {
++ case 0 ... 9:
++ return (i + '0');
++ break;
++ case 10 ... 15:
++ return (i - 10 + 'a');
++ break;
++ default:
++ if (net_ratelimit())
++ printk("layer7: Problem in dec2hex\n");
++ return '\0';
++ }
++}
++
++static char * hex_print(unsigned char * s)
++{
++ char * g = kmalloc(strlen(s)*3 + 1, GFP_ATOMIC);
++ int i;
++
++ if(!g) {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in hex_print, "
++ "bailing.\n");
++ return NULL;
++ }
++
++ for(i = 0; i < strlen(s); i++) {
++ g[i*3 ] = dec2hex(s[i]/16);
++ g[i*3 + 1] = dec2hex(s[i]%16);
++ g[i*3 + 2] = ' ';
++ }
++ g[i*3] = '\0';
++
++ return g;
++}
++#endif // DEBUG
++
++/* Use instead of regcomp. As we expect to be seeing the same regexps over and
++over again, it make sense to cache the results. */
++static regexp * compile_and_cache(const char * regex_string,
++ const char * protocol)
++{
++ struct pattern_cache * node = first_pattern_cache;
++ struct pattern_cache * last_pattern_cache = first_pattern_cache;
++ struct pattern_cache * tmp;
++ unsigned int len;
++
++ while (node != NULL) {
++ if (!strcmp(node->regex_string, regex_string))
++ return node->pattern;
++
++ last_pattern_cache = node;/* points at the last non-NULL node */
++ node = node->next;
++ }
++
++ /* If we reach the end of the list, then we have not yet cached
++ the pattern for this regex. Let's do that now.
++ Be paranoid about running out of memory to avoid list corruption. */
++ tmp = kmalloc(sizeof(struct pattern_cache), GFP_ATOMIC);
++
++ if(!tmp) {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "compile_and_cache, bailing.\n");
++ return NULL;
++ }
++
++ tmp->regex_string = kmalloc(strlen(regex_string) + 1, GFP_ATOMIC);
++ tmp->pattern = kmalloc(sizeof(struct regexp), GFP_ATOMIC);
++ tmp->next = NULL;
++
++ if(!tmp->regex_string || !tmp->pattern) {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "compile_and_cache, bailing.\n");
++ kfree(tmp->regex_string);
++ kfree(tmp->pattern);
++ kfree(tmp);
++ return NULL;
++ }
++
++ /* Ok. The new node is all ready now. */
++ node = tmp;
++
++ if(first_pattern_cache == NULL) /* list is empty */
++ first_pattern_cache = node; /* make node the beginning */
++ else
++ last_pattern_cache->next = node; /* attach node to the end */
++
++ /* copy the string and compile the regex */
++ len = strlen(regex_string);
++ DPRINTK("About to compile this: \"%s\"\n", regex_string);
++ node->pattern = regcomp((char *)regex_string, &len);
++ if ( !node->pattern ) {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: Error compiling regexp "
++ "\"%s\" (%s)\n",
++ regex_string, protocol);
++ /* pattern is now cached as NULL, so we won't try again. */
++ }
++
++ strcpy(node->regex_string, regex_string);
++ return node->pattern;
++}
++
++static int can_handle(const struct sk_buff *skb)
++{
++ if(!ip_hdr(skb)) /* not IP */
++ return 0;
++ if(ip_hdr(skb)->protocol != IPPROTO_TCP &&
++ ip_hdr(skb)->protocol != IPPROTO_UDP &&
++ ip_hdr(skb)->protocol != IPPROTO_ICMP)
++ return 0;
++ return 1;
++}
++
++/* Returns offset the into the skb->data that the application data starts */
++static int app_data_offset(const struct sk_buff *skb)
++{
++ /* In case we are ported somewhere (ebtables?) where ip_hdr(skb)
++ isn't set, this can be gotten from 4*(skb->data[0] & 0x0f) as well. */
++ int ip_hl = 4*ip_hdr(skb)->ihl;
++
++ if( ip_hdr(skb)->protocol == IPPROTO_TCP ) {
++ /* 12 == offset into TCP header for the header length field.
++ Can't get this with skb->h.th->doff because the tcphdr
++ struct doesn't get set when routing (this is confirmed to be
++ true in Netfilter as well as QoS.) */
++ int tcp_hl = 4*(skb->data[ip_hl + 12] >> 4);
++
++ return ip_hl + tcp_hl;
++ } else if( ip_hdr(skb)->protocol == IPPROTO_UDP ) {
++ return ip_hl + 8; /* UDP header is always 8 bytes */
++ } else if( ip_hdr(skb)->protocol == IPPROTO_ICMP ) {
++ return ip_hl + 8; /* ICMP header is 8 bytes */
++ } else {
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: tried to handle unknown "
++ "protocol!\n");
++ return ip_hl + 8; /* something reasonable */
++ }
++}
++
++/* handles whether there's a match when we aren't appending data anymore */
++static int match_no_append(struct nf_conn * conntrack,
++ struct nf_conn * master_conntrack,
++ enum ip_conntrack_info ctinfo,
++ enum ip_conntrack_info master_ctinfo,
++ const struct xt_layer7_info * info)
++{
++ /* If we're in here, throw the app data away */
++ if(master_conntrack->layer7.app_data != NULL) {
++
++ #ifdef CONFIG_IP_NF_MATCH_LAYER7_DEBUG
++ if(!master_conntrack->layer7.app_proto) {
++ char * f =
++ friendly_print(master_conntrack->layer7.app_data);
++ char * g =
++ hex_print(master_conntrack->layer7.app_data);
++ DPRINTK("\nl7-filter gave up after %d bytes "
++ "(%d packets):\n%s\n",
++ strlen(f), total_acct_packets(master_conntrack), f);
++ kfree(f);
++ DPRINTK("In hex: %s\n", g);
++ kfree(g);
++ }
++ #endif
++
++ kfree(master_conntrack->layer7.app_data);
++ master_conntrack->layer7.app_data = NULL; /* don't free again */
++ }
++
++ if(master_conntrack->layer7.app_proto){
++ /* Here child connections set their .app_proto (for /proc) */
++ if(!conntrack->layer7.app_proto) {
++ conntrack->layer7.app_proto =
++ kmalloc(strlen(master_conntrack->layer7.app_proto)+1,
++ GFP_ATOMIC);
++ if(!conntrack->layer7.app_proto){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory "
++ "in match_no_append, "
++ "bailing.\n");
++ return 1;
++ }
++ strcpy(conntrack->layer7.app_proto,
++ master_conntrack->layer7.app_proto);
++ }
++
++ return (!strcmp(master_conntrack->layer7.app_proto,
++ info->protocol));
++ }
++ else {
++ /* If not classified, set to "unknown" to distinguish from
++ connections that are still being tested. */
++ master_conntrack->layer7.app_proto =
++ kmalloc(strlen("unknown")+1, GFP_ATOMIC);
++ if(!master_conntrack->layer7.app_proto){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "match_no_append, bailing.\n");
++ return 1;
++ }
++ strcpy(master_conntrack->layer7.app_proto, "unknown");
++ return 0;
++ }
++}
++
++/* add the new app data to the conntrack. Return number of bytes added. */
++static int add_data(struct nf_conn * master_conntrack,
++ char * app_data, int appdatalen)
++{
++ int length = 0, i;
++ int oldlength = master_conntrack->layer7.app_data_len;
++
++ /* This is a fix for a race condition by Deti Fliegl. However, I'm not
++ clear on whether the race condition exists or whether this really
++ fixes it. I might just be being dense... Anyway, if it's not really
++ a fix, all it does is waste a very small amount of time. */
++ if(!master_conntrack->layer7.app_data) return 0;
++
++ /* Strip nulls. Make everything lower case (our regex lib doesn't
++ do case insensitivity). Add it to the end of the current data. */
++ for(i = 0; i < maxdatalen-oldlength-1 &&
++ i < appdatalen; i++) {
++ if(app_data[i] != '\0') {
++ /* the kernel version of tolower mungs 'upper ascii' */
++ master_conntrack->layer7.app_data[length+oldlength] =
++ isascii(app_data[i])?
++ tolower(app_data[i]) : app_data[i];
++ length++;
++ }
++ }
++
++ master_conntrack->layer7.app_data[length+oldlength] = '\0';
++ master_conntrack->layer7.app_data_len = length + oldlength;
++
++ return length;
++}
++
++/* taken from drivers/video/modedb.c */
++static int my_atoi(const char *s)
++{
++ int val = 0;
++
++ for (;; s++) {
++ switch (*s) {
++ case '0'...'9':
++ val = 10*val+(*s-'0');
++ break;
++ default:
++ return val;
++ }
++ }
++}
++
++/* write out num_packets to userland. */
++static int layer7_read_proc(char* page, char ** start, off_t off, int count,
++ int* eof, void * data)
++{
++ if(num_packets > 99 && net_ratelimit())
++ printk(KERN_ERR "layer7: NOT REACHED. num_packets too big\n");
++
++ page[0] = num_packets/10 + '0';
++ page[1] = num_packets%10 + '0';
++ page[2] = '\n';
++ page[3] = '\0';
++
++ *eof=1;
++
++ return 3;
++}
++
++/* Read in num_packets from userland */
++static int layer7_write_proc(struct file* file, const char* buffer,
++ unsigned long count, void *data)
++{
++ char * foo = kmalloc(count, GFP_ATOMIC);
++
++ if(!foo){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory, bailing. "
++ "num_packets unchanged.\n");
++ return count;
++ }
++
++ if(copy_from_user(foo, buffer, count)) {
++ return -EFAULT;
++ }
++
++
++ num_packets = my_atoi(foo);
++ kfree (foo);
++
++ /* This has an arbitrary limit to make the math easier. I'm lazy.
++ But anyway, 99 is a LOT! If you want more, you're doing it wrong! */
++ if(num_packets > 99) {
++ printk(KERN_WARNING "layer7: num_packets can't be > 99.\n");
++ num_packets = 99;
++ } else if(num_packets < 1) {
++ printk(KERN_WARNING "layer7: num_packets can't be < 1.\n");
++ num_packets = 1;
++ }
++
++ return count;
++}
++
++static bool
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
++match(const struct sk_buff *skbin, const struct xt_match_param *par)
++#else
++match(const struct sk_buff *skbin,
++ const struct net_device *in,
++ const struct net_device *out,
++ const struct xt_match *match,
++ const void *matchinfo,
++ int offset,
++ unsigned int protoff,
++ bool *hotdrop)
++#endif
++{
++ /* sidestep const without getting a compiler warning... */
++ struct sk_buff * skb = (struct sk_buff *)skbin;
++
++ const struct xt_layer7_info * info =
++ #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
++ par->matchinfo;
++ #else
++ matchinfo;
++ #endif
++
++ enum ip_conntrack_info master_ctinfo, ctinfo;
++ struct nf_conn *master_conntrack, *conntrack;
++ unsigned char * app_data;
++ unsigned int pattern_result, appdatalen;
++ regexp * comppattern;
++
++ /* Be paranoid/incompetent - lock the entire match function. */
++ spin_lock_bh(&l7_lock);
++
++ if(!can_handle(skb)){
++ DPRINTK("layer7: This is some protocol I can't handle.\n");
++ spin_unlock_bh(&l7_lock);
++ return info->invert;
++ }
++
++ /* Treat parent & all its children together as one connection, except
++ for the purpose of setting conntrack->layer7.app_proto in the actual
++ connection. This makes /proc/net/ip_conntrack more satisfying. */
++ if(!(conntrack = nf_ct_get(skb, &ctinfo)) ||
++ !(master_conntrack=nf_ct_get(skb,&master_ctinfo))){
++ DPRINTK("layer7: couldn't get conntrack.\n");
++ spin_unlock_bh(&l7_lock);
++ return info->invert;
++ }
++
++ /* Try to get a master conntrack (and its master etc) for FTP, etc. */
++ while (master_ct(master_conntrack) != NULL)
++ master_conntrack = master_ct(master_conntrack);
++
++ /* if we've classified it or seen too many packets */
++ if(total_acct_packets(master_conntrack) > num_packets ||
++ master_conntrack->layer7.app_proto) {
++
++ pattern_result = match_no_append(conntrack, master_conntrack,
++ ctinfo, master_ctinfo, info);
++
++ /* skb->cb[0] == seen. Don't do things twice if there are
++ multiple l7 rules. I'm not sure that using cb for this purpose
++ is correct, even though it says "put your private variables
++ there". But it doesn't look like it is being used for anything
++ else in the skbs that make it here. */
++ skb->cb[0] = 1; /* marking it seen here's probably irrelevant */
++
++ spin_unlock_bh(&l7_lock);
++ return (pattern_result ^ info->invert);
++ }
++
++ if(skb_is_nonlinear(skb)){
++ if(skb_linearize(skb) != 0){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: failed to linearize "
++ "packet, bailing.\n");
++ spin_unlock_bh(&l7_lock);
++ return info->invert;
++ }
++ }
++
++ /* now that the skb is linearized, it's safe to set these. */
++ app_data = skb->data + app_data_offset(skb);
++ appdatalen = skb_tail_pointer(skb) - app_data;
++
++ /* the return value gets checked later, when we're ready to use it */
++ comppattern = compile_and_cache(info->pattern, info->protocol);
++
++ /* On the first packet of a connection, allocate space for app data */
++ if(total_acct_packets(master_conntrack) == 1 && !skb->cb[0] &&
++ !master_conntrack->layer7.app_data){
++ master_conntrack->layer7.app_data =
++ kmalloc(maxdatalen, GFP_ATOMIC);
++ if(!master_conntrack->layer7.app_data){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "match, bailing.\n");
++ spin_unlock_bh(&l7_lock);
++ return info->invert;
++ }
++
++ master_conntrack->layer7.app_data[0] = '\0';
++ }
++
++ /* Can be here, but unallocated, if numpackets is increased near
++ the beginning of a connection */
++ if(master_conntrack->layer7.app_data == NULL){
++ spin_unlock_bh(&l7_lock);
++ return info->invert; /* unmatched */
++ }
++
++ if(!skb->cb[0]){
++ int newbytes;
++ newbytes = add_data(master_conntrack, app_data, appdatalen);
++
++ if(newbytes == 0) { /* didn't add any data */
++ skb->cb[0] = 1;
++ /* Didn't match before, not going to match now */
++ spin_unlock_bh(&l7_lock);
++ return info->invert;
++ }
++ }
++
++ /* If looking for "unknown", then never match. "Unknown" means that
++ we've given up; we're still trying with these packets. */
++ if(!strcmp(info->protocol, "unknown")) {
++ pattern_result = 0;
++ /* If looking for "unset", then always match. "Unset" means that we
++ haven't yet classified the connection. */
++ } else if(!strcmp(info->protocol, "unset")) {
++ pattern_result = 2;
++ DPRINTK("layer7: matched unset: not yet classified "
++ "(%d/%d packets)\n",
++ total_acct_packets(master_conntrack), num_packets);
++ /* If the regexp failed to compile, don't bother running it */
++ } else if(comppattern &&
++ regexec(comppattern, master_conntrack->layer7.app_data)){
++ DPRINTK("layer7: matched %s\n", info->protocol);
++ pattern_result = 1;
++ } else pattern_result = 0;
++
++ if(pattern_result == 1) {
++ master_conntrack->layer7.app_proto =
++ kmalloc(strlen(info->protocol)+1, GFP_ATOMIC);
++ if(!master_conntrack->layer7.app_proto){
++ if (net_ratelimit())
++ printk(KERN_ERR "layer7: out of memory in "
++ "match, bailing.\n");
++ spin_unlock_bh(&l7_lock);
++ return (pattern_result ^ info->invert);
++ }
++ strcpy(master_conntrack->layer7.app_proto, info->protocol);
++ } else if(pattern_result > 1) { /* cleanup from "unset" */
++ pattern_result = 1;
++ }
++
++ /* mark the packet seen */
++ skb->cb[0] = 1;
++
++ spin_unlock_bh(&l7_lock);
++ return (pattern_result ^ info->invert);
++}
++
++// load nf_conntrack_ipv4
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
++static bool check(const struct xt_mtchk_param *par)
++{
++ if (nf_ct_l3proto_try_module_get(par->match->family) < 0) {
++ printk(KERN_WARNING "can't load conntrack support for "
++ "proto=%d\n", par->match->family);
++#else
++static bool check(const char *tablename, const void *inf,
++ const struct xt_match *match, void *matchinfo,
++ unsigned int hook_mask)
++{
++ if (nf_ct_l3proto_try_module_get(match->family) < 0) {
++ printk(KERN_WARNING "can't load conntrack support for "
++ "proto=%d\n", match->family);
++#endif
++ return 0;
++ }
++ return 1;
++}
++
++
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
++ static void destroy(const struct xt_mtdtor_param *par)
++ {
++ nf_ct_l3proto_module_put(par->match->family);
++ }
++#else
++ static void destroy(const struct xt_match *match, void *matchinfo)
++ {
++ nf_ct_l3proto_module_put(match->family);
++ }
++#endif
++
++static struct xt_match xt_layer7_match[] __read_mostly = {
++{
++ .name = "layer7",
++ .family = AF_INET,
++ .checkentry = check,
++ .match = match,
++ .destroy = destroy,
++ .matchsize = sizeof(struct xt_layer7_info),
++ .me = THIS_MODULE
++}
++};
++
++static void layer7_cleanup_proc(void)
++{
++ remove_proc_entry("layer7_numpackets", init_net.proc_net);
++}
++
++/* register the proc file */
++static void layer7_init_proc(void)
++{
++ struct proc_dir_entry* entry;
++ entry = create_proc_entry("layer7_numpackets", 0644, init_net.proc_net);
++ entry->read_proc = layer7_read_proc;
++ entry->write_proc = layer7_write_proc;
++}
++
++static int __init xt_layer7_init(void)
++{
++ need_conntrack();
++
++ layer7_init_proc();
++ if(maxdatalen < 1) {
++ printk(KERN_WARNING "layer7: maxdatalen can't be < 1, "
++ "using 1\n");
++ maxdatalen = 1;
++ }
++ /* This is not a hard limit. It's just here to prevent people from
++ bringing their slow machines to a grinding halt. */
++ else if(maxdatalen > 65536) {
++ printk(KERN_WARNING "layer7: maxdatalen can't be > 65536, "
++ "using 65536\n");
++ maxdatalen = 65536;
++ }
++ return xt_register_matches(xt_layer7_match,
++ ARRAY_SIZE(xt_layer7_match));
++}
++
++static void __exit xt_layer7_fini(void)
++{
++ layer7_cleanup_proc();
++ xt_unregister_matches(xt_layer7_match, ARRAY_SIZE(xt_layer7_match));
++}
++
++module_init(xt_layer7_init);
++module_exit(xt_layer7_fini);
+
