diff options
| -rw-r--r-- | target/linux/generic-2.6/patches-2.6.27/100-netfilter_layer7_2.17.patch | 1452 | ||||
| -rw-r--r-- | target/linux/generic-2.6/patches-2.6.27/101-netfilter_layer7_pktmatch.patch | 40 |
2 files changed, 770 insertions, 722 deletions
diff --git a/target/linux/generic-2.6/patches-2.6.27/100-netfilter_layer7_2.17.patch b/target/linux/generic-2.6/patches-2.6.27/100-netfilter_layer7_2.17.patch index 26b04e51ca..8da0d1e7b3 100644 --- a/target/linux/generic-2.6/patches-2.6.27/100-netfilter_layer7_2.17.patch +++ b/target/linux/generic-2.6/patches-2.6.27/100-netfilter_layer7_2.17.patch @@ -1,6 +1,54 @@ +diff --git a/include/linux/netfilter/xt_layer7.h b/include/linux/netfilter/xt_layer7.h +new file mode 100644 +index 0000000..147cd64 +--- /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 */ +diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h +index b76a868..2a0bb9b 100644 +--- a/include/net/netfilter/nf_conntrack.h ++++ b/include/net/netfilter/nf_conntrack.h +@@ -118,6 +118,22 @@ 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; + +diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig +index 25dcef9..29fe15d 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig -@@ -757,6 +757,27 @@ config NETFILTER_XT_MATCH_STATE +@@ -795,6 +795,27 @@ config NETFILTER_XT_MATCH_STATE To compile it as a module, choose M here. If unsure, say N. @@ -27,654 +75,58 @@ + config NETFILTER_XT_MATCH_STATISTIC tristate '"statistic" match support' - depends on NETFILTER_XTABLES + depends on NETFILTER_ADVANCED +diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile +index da3d909..c15b75d 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile -@@ -78,6 +78,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_RATEEST) - obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o +@@ -84,6 +84,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_RECENT) += xt_recent.o obj-$(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 ---- /dev/null -+++ b/net/netfilter/xt_layer7.c -@@ -0,0 +1,634 @@ -+/* -+ Kernel module to match application layer (OSI layer 7) data in connections. -+ -+ http://l7-filter.sf.net -+ -+ (C) 2003, 2004, 2005, 2006, 2007 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> -+#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("2.17"); -+ -+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 -+ -+#define TOTAL_PACKETS master_conntrack->counters[IP_CT_DIR_ORIGINAL].packets + \ -+ master_conntrack->counters[IP_CT_DIR_REPLY].packets -+ -+/* 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); -+ -+#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_PACKETS, f); -+ kfree(f); -+ DPRINTK("In hex: %s\n", g); -+ kfree(g); -+ } +diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c +index 622d7c6..32959cc 100644 +--- a/net/netfilter/nf_conntrack_core.c ++++ b/net/netfilter/nf_conntrack_core.c +@@ -201,6 +201,14 @@ destroy_conntrack(struct nf_conntrack *nfct) + * 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 + -+ 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 -+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) -+{ -+ /* sidestep const without getting a compiler warning... */ -+ struct sk_buff * skb = (struct sk_buff *)skbin; -+ -+ const struct xt_layer7_info * info = matchinfo; -+ 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_PACKETS > 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_PACKETS == 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_PACKETS, 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); -+} -+ -+static bool check(const char *tablename, -+ const void *inf, -+ const struct xt_match *match, -+ void *matchinfo, -+ unsigned int hook_mask) -+ -+{ -+ // load nf_conntrack_ipv4 -+ if (nf_ct_l3proto_try_module_get(match->family) < 0) { -+ printk(KERN_WARNING "can't load conntrack support for " -+ "proto=%d\n", match->family); -+ return false; -+ } -+ return true; -+} -+ -+static void -+destroy(const struct xt_match *match, void *matchinfo) -+{ -+ nf_ct_l3proto_module_put(match->family); -+} -+ -+static struct xt_match xt_layer7_match[] = { -+{ -+ .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) -+{ -+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) -+ remove_proc_entry("layer7_numpackets", proc_net); -+#else -+ remove_proc_entry("layer7_numpackets", init_net.proc_net); -+#endif -+} -+ -+/* register the proc file */ -+static void layer7_init_proc(void) -+{ -+ struct proc_dir_entry* entry; -+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) -+ entry = create_proc_entry("layer7_numpackets", 0644, proc_net); -+#else -+ entry = create_proc_entry("layer7_numpackets", 0644, init_net.proc_net); + /* We overload first tuple to link into unconfirmed list. */ + if (!nf_ct_is_confirmed(ct)) { + BUG_ON(hlist_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode)); +diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c +index 98106d4..774acad 100644 +--- a/net/netfilter/nf_conntrack_standalone.c ++++ b/net/netfilter/nf_conntrack_standalone.c +@@ -165,6 +165,12 @@ static int ct_seq_show(struct seq_file *s, void *v) + return -ENOSPC; + #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 -+ 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); + if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use))) + return -ENOSPC; + +diff --git a/net/netfilter/regexp/regexp.c b/net/netfilter/regexp/regexp.c +new file mode 100644 +index 0000000..9006988 --- /dev/null +++ b/net/netfilter/regexp/regexp.c @@ -0,0 +1,1197 @@ @@ -914,7 +366,7 @@ + register int len; + int flags; + struct match_globals g; -+ ++ + /* commented out by ethan + extern char *malloc(); + */ @@ -1041,7 +493,7 @@ + } + + /* Make a closing node, and hook it on the end. */ -+ ender = regnode(g, (paren) ? CLOSE+parno : END); ++ ender = regnode(g, (paren) ? CLOSE+parno : END); + regtail(g, ret, ender); + + /* Hook the tails of the branches to the closing node. */ @@ -1875,6 +1327,9 @@ +#endif + + +diff --git a/net/netfilter/regexp/regexp.h b/net/netfilter/regexp/regexp.h +new file mode 100644 +index 0000000..a72eba7 --- /dev/null +++ b/net/netfilter/regexp/regexp.h @@ -0,0 +1,41 @@ @@ -1919,6 +1374,9 @@ +void regerror(char *s); + +#endif +diff --git a/net/netfilter/regexp/regmagic.h b/net/netfilter/regexp/regmagic.h +new file mode 100644 +index 0000000..5acf447 --- /dev/null +++ b/net/netfilter/regexp/regmagic.h @@ -0,0 +1,5 @@ @@ -1927,6 +1385,9 @@ + * number; the start node begins in the second byte. + */ +#define MAGIC 0234 +diff --git a/net/netfilter/regexp/regsub.c b/net/netfilter/regexp/regsub.c +new file mode 100644 +index 0000000..339631f --- /dev/null +++ b/net/netfilter/regexp/regsub.c @@ -0,0 +1,95 @@ @@ -1986,7 +1447,7 @@ + register char c; + register int no; + register int len; -+ ++ + /* Not necessary and gcc doesn't like it -MLS */ + /*extern char *strncpy();*/ + @@ -2025,77 +1486,660 @@ + } + *dst++ = '\0'; +} ---- a/net/netfilter/nf_conntrack_core.c -+++ b/net/netfilter/nf_conntrack_core.c -@@ -206,6 +206,14 @@ 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 +diff --git a/net/netfilter/xt_layer7.c b/net/netfilter/xt_layer7.c +new file mode 100644 +index 0000000..a9b88d3 +--- /dev/null ++++ b/net/netfilter/xt_layer7.c +@@ -0,0 +1,651 @@ ++/* ++ Kernel module to match application layer (OSI layer 7) data in connections. + ++ http://l7-filter.sf.net + - /* We overload first tuple to link into unconfirmed list. */ - if (!nf_ct_is_confirmed(ct)) { - BUG_ON(hlist_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode)); ---- a/net/netfilter/nf_conntrack_standalone.c -+++ b/net/netfilter/nf_conntrack_standalone.c -@@ -162,7 +162,12 @@ static int ct_seq_show(struct seq_file * - return -ENOSPC; - #endif - -- if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use))) -+#if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE) -+ if(ct->layer7.app_proto) -+ if(seq_printf(s, "l7proto=%s ", ct->layer7.app_proto)) -+ return -ENOSPC; ++ (C) 2003, 2004, 2005, 2006, 2007 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 -+ if (seq_printf(s, "asdfuse=%u\n", atomic_read(&ct->ct_general.use))) - return -ENOSPC; - - return 0; ---- a/include/net/netfilter/nf_conntrack.h -+++ b/include/net/netfilter/nf_conntrack.h -@@ -118,6 +118,22 @@ 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; ++#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("2.19"); ++ ++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 + - /* Storage reserved for other modules: */ - union nf_conntrack_proto proto; - ---- /dev/null -+++ b/include/linux/netfilter/xt_layer7.h -@@ -0,0 +1,13 @@ -+#ifndef _XT_LAYER7_H -+#define _XT_LAYER7_H ++/* Number of packets whose data we look at. ++This can be modified through /proc/net/layer7_numpackets */ ++static int num_packets = 10; + -+#define MAX_PATTERN_LEN 8192 -+#define MAX_PROTOCOL_LEN 256 ++static struct pattern_cache { ++ char * regex_string; ++ regexp * pattern; ++ struct pattern_cache * next; ++} * first_pattern_cache = NULL; + -+struct xt_layer7_info { -+ char protocol[MAX_PROTOCOL_LEN]; -+ char pattern[MAX_PATTERN_LEN]; -+ u_int8_t invert; ++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 ++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) ++{ ++ /* sidestep const without getting a compiler warning... */ ++ struct sk_buff * skb = (struct sk_buff *)skbin; ++ ++ const struct xt_layer7_info * info = matchinfo; ++ 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); ++} ++ ++static bool check(const char *tablename, ++ const void *inf, ++ const struct xt_match *match, ++ void *matchinfo, ++ unsigned int hook_mask) ++ ++{ ++ // load nf_conntrack_ipv4 ++ if (nf_ct_l3proto_try_module_get(match->family) < 0) { ++ printk(KERN_WARNING "can't load conntrack support for " ++ "proto=%d\n", match->family); ++ return 0; ++ } ++ return 1; ++} ++ ++static void ++destroy(const struct xt_match *match, void *matchinfo) ++{ ++ nf_ct_l3proto_module_put(match->family); ++} ++ ++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 ++} +}; + -+#endif /* _XT_LAYER7_H */ ++static void layer7_cleanup_proc(void) ++{ ++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) ++ remove_proc_entry("layer7_numpackets", proc_net); ++#else ++ remove_proc_entry("layer7_numpackets", init_net.proc_net); ++#endif ++} ++ ++/* register the proc file */ ++static void layer7_init_proc(void) ++{ ++ struct proc_dir_entry* entry; ++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) ++ entry = create_proc_entry("layer7_numpackets", 0644, proc_net); ++#else ++ entry = create_proc_entry("layer7_numpackets", 0644, init_net.proc_net); ++#endif ++ 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); diff --git a/target/linux/generic-2.6/patches-2.6.27/101-netfilter_layer7_pktmatch.patch b/target/linux/generic-2.6/patches-2.6.27/101-netfilter_layer7_pktmatch.patch index ad0fdb823f..0152957c21 100644 --- a/target/linux/generic-2.6/patches-2.6.27/101-netfilter_layer7_pktmatch.patch +++ b/target/linux/generic-2.6/patches-2.6.27/101-netfilter_layer7_pktmatch.patch @@ -1,3 +1,5 @@ +diff --git a/include/linux/netfilter/xt_layer7.h b/include/linux/netfilter/xt_layer7.h +index 147cd64..c38d3c4 100644 --- a/include/linux/netfilter/xt_layer7.h +++ b/include/linux/netfilter/xt_layer7.h @@ -8,6 +8,7 @@ struct xt_layer7_info { @@ -8,9 +10,11 @@ }; #endif /* _XT_LAYER7_H */ +diff --git a/net/netfilter/xt_layer7.c b/net/netfilter/xt_layer7.c +index a9b88d3..e0e962d 100644 --- a/net/netfilter/xt_layer7.c +++ b/net/netfilter/xt_layer7.c -@@ -297,34 +297,36 @@ static int match_no_append(struct nf_con +@@ -314,33 +314,35 @@ static int match_no_append(struct nf_conn * conntrack, } /* add the new app data to the conntrack. Return number of bytes added. */ @@ -20,10 +24,10 @@ { 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 +- +- /* 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; + if (!target) return 0; @@ -32,12 +36,12 @@ do case insensitivity). Add it to the end of the current data. */ - for(i = 0; i < maxdatalen-oldlength-1 && - i < appdatalen; i++) { -+ for(i = 0; i < maxdatalen-offset-1 && i < len; i++) { ++ for(i = 0; i < maxdatalen-offset-1 && i < len; i++) { if(app_data[i] != '\0') { /* the kernel version of tolower mungs 'upper ascii' */ - master_conntrack->layer7.app_data[length+oldlength] = + target[length+offset] = - isascii(app_data[i])? + isascii(app_data[i])? tolower(app_data[i]) : app_data[i]; length++; } @@ -46,21 +50,21 @@ + + return length; +} - -- master_conntrack->layer7.app_data[length+oldlength] = '\0'; -- master_conntrack->layer7.app_data_len = length + oldlength; ++ +/* 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; +- master_conntrack->layer7.app_data[length+oldlength] = '\0'; +- master_conntrack->layer7.app_data_len = length + oldlength; + length = add_datastr(master_conntrack->layer7.app_data, master_conntrack->layer7.app_data_len, app_data, appdatalen); + master_conntrack->layer7.app_data_len += length; + return length; } - -@@ -411,7 +413,7 @@ match(const struct sk_buff *skbin, +@@ -428,7 +430,7 @@ match(const struct sk_buff *skbin, const struct xt_layer7_info * info = matchinfo; enum ip_conntrack_info master_ctinfo, ctinfo; struct nf_conn *master_conntrack, *conntrack; @@ -69,18 +73,18 @@ unsigned int pattern_result, appdatalen; regexp * comppattern; -@@ -439,8 +441,8 @@ match(const struct sk_buff *skbin, +@@ -456,8 +458,8 @@ match(const struct sk_buff *skbin, master_conntrack = master_ct(master_conntrack); /* if we've classified it or seen too many packets */ -- if(TOTAL_PACKETS > num_packets || +- if(total_acct_packets(master_conntrack) > num_packets || - master_conntrack->layer7.app_proto) { -+ if(!info->pkt && (TOTAL_PACKETS > num_packets || ++ if(!info->pkt && (total_acct_packets(master_conntrack) > num_packets || + master_conntrack->layer7.app_proto)) { - pattern_result = match_no_append(conntrack, master_conntrack, + pattern_result = match_no_append(conntrack, master_conntrack, ctinfo, master_ctinfo, info); -@@ -473,6 +475,25 @@ match(const struct sk_buff *skbin, +@@ -490,6 +492,25 @@ match(const struct sk_buff *skbin, /* the return value gets checked later, when we're ready to use it */ comppattern = compile_and_cache(info->pattern, info->protocol); @@ -104,5 +108,5 @@ + } + /* On the first packet of a connection, allocate space for app data */ - if(TOTAL_PACKETS == 1 && !skb->cb[0] && + if(total_acct_packets(master_conntrack) == 1 && !skb->cb[0] && !master_conntrack->layer7.app_data){ |