[NETFILTER]: sip conntrack: do case insensitive SIP header search
[deliverable/linux.git] / net / ipv4 / netfilter / ip_conntrack_sip.c
index 4f222d6be009ac22aa6519b1619aedc1df65500a..a9c0d1d3e56f0fd745ed6d170d664f31047634bb 100644 (file)
@@ -8,7 +8,6 @@
  * published by the Free Software Foundation.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/ctype.h>
 #include <linux/skbuff.h>
@@ -53,20 +52,33 @@ unsigned int (*ip_nat_sdp_hook)(struct sk_buff **pskb,
                                const char *dptr);
 EXPORT_SYMBOL_GPL(ip_nat_sdp_hook);
 
-int ct_sip_get_info(const char *dptr, size_t dlen,
-                               unsigned int *matchoff,
-                               unsigned int *matchlen,
-                               struct sip_header_nfo *hnfo);
-EXPORT_SYMBOL_GPL(ct_sip_get_info);
-
-
 static int digits_len(const char *dptr, const char *limit, int *shift);
 static int epaddr_len(const char *dptr, const char *limit, int *shift);
 static int skp_digits_len(const char *dptr, const char *limit, int *shift);
 static int skp_epaddr_len(const char *dptr, const char *limit, int *shift);
 
-struct sip_header_nfo ct_sip_hdrs[] = {
-       {       /* Via header */
+struct sip_header_nfo {
+       const char      *lname;
+       const char      *sname;
+       const char      *ln_str;
+       size_t          lnlen;
+       size_t          snlen;
+       size_t          ln_strlen;
+       int             case_sensitive;
+       int             (*match_len)(const char *, const char *, int *);
+};
+
+static struct sip_header_nfo ct_sip_hdrs[] = {
+       [POS_REQ_HEADER] = {    /* SIP Requests headers */
+               .lname          = "sip:",
+               .lnlen          = sizeof("sip:") - 1,
+               .sname          = "sip:",
+               .snlen          = sizeof("sip:") - 1, /* yes, i know.. ;) */
+               .ln_str         = "@",
+               .ln_strlen      = sizeof("@") - 1,
+               .match_len      = epaddr_len
+       },
+       [POS_VIA] = {           /* SIP Via header */
                .lname          = "Via:",
                .lnlen          = sizeof("Via:") - 1,
                .sname          = "\r\nv:",
@@ -75,7 +87,7 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof("UDP ") - 1,
                .match_len      = epaddr_len,
        },
-       {       /* Contact header */
+       [POS_CONTACT] = {       /* SIP Contact header */
                .lname          = "Contact:",
                .lnlen          = sizeof("Contact:") - 1,
                .sname          = "\r\nm:",
@@ -84,7 +96,7 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof("sip:") - 1,
                .match_len      = skp_epaddr_len
        },
-       {       /* Content length header */
+       [POS_CONTENT] = {       /* SIP Content length header */
                .lname          = "Content-Length:",
                .lnlen          = sizeof("Content-Length:") - 1,
                .sname          = "\r\nl:",
@@ -93,7 +105,8 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof(":") - 1,
                .match_len      = skp_digits_len
        },
-       {       /* SDP media info */
+       [POS_MEDIA] = {         /* SDP media info */
+               .case_sensitive = 1,
                .lname          = "\nm=",
                .lnlen          = sizeof("\nm=") - 1,
                .sname          = "\rm=",
@@ -102,7 +115,8 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof("audio ") - 1,
                .match_len      = digits_len
        },
-       {       /* SDP owner address*/
+       [POS_OWNER] = {         /* SDP owner address*/
+               .case_sensitive = 1,
                .lname          = "\no=",
                .lnlen          = sizeof("\no=") - 1,
                .sname          = "\ro=",
@@ -111,7 +125,8 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof("IN IP4 ") - 1,
                .match_len      = epaddr_len
        },
-       {       /* SDP connection info */
+       [POS_CONNECTION] = {    /* SDP connection info */
+               .case_sensitive = 1,
                .lname          = "\nc=",
                .lnlen          = sizeof("\nc=") - 1,
                .sname          = "\rc=",
@@ -120,16 +135,8 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .ln_strlen      = sizeof("IN IP4 ") - 1,
                .match_len      = epaddr_len
        },
-       {       /* Requests headers */
-               .lname          = "sip:",
-               .lnlen          = sizeof("sip:") - 1,
-               .sname          = "sip:",
-               .snlen          = sizeof("sip:") - 1, /* yes, i know.. ;) */
-               .ln_str         = "@",
-               .ln_strlen      = sizeof("@") - 1,
-               .match_len      = epaddr_len
-       },
-       {       /* SDP version header */
+       [POS_SDP_HEADER] = {    /* SDP version header */
+               .case_sensitive = 1,
                .lname          = "\nv=",
                .lnlen          = sizeof("\nv=") - 1,
                .sname          = "\rv=",
@@ -139,7 +146,6 @@ struct sip_header_nfo ct_sip_hdrs[] = {
                .match_len      = digits_len
        }
 };
-EXPORT_SYMBOL_GPL(ct_sip_hdrs);
 
 /* get line lenght until first CR or LF seen. */
 int ct_sip_lnlen(const char *line, const char *limit)
@@ -160,13 +166,19 @@ EXPORT_SYMBOL_GPL(ct_sip_lnlen);
 
 /* Linear string search, case sensitive. */
 const char *ct_sip_search(const char *needle, const char *haystack,
-                          size_t needle_len, size_t haystack_len)
+                         size_t needle_len, size_t haystack_len,
+                         int case_sensitive)
 {
        const char *limit = haystack + (haystack_len - needle_len);
 
        while (haystack <= limit) {
-               if (memcmp(haystack, needle, needle_len) == 0)
-                       return haystack;
+               if (case_sensitive) {
+                       if (strncmp(haystack, needle, needle_len) == 0)
+                               return haystack;
+               } else {
+                       if (strnicmp(haystack, needle, needle_len) == 0)
+                               return haystack;
+               }
                haystack++;
        }
        return NULL;
@@ -194,7 +206,7 @@ static int skp_digits_len(const char *dptr, const char *limit, int *shift)
 
 /* Simple ipaddr parser.. */
 static int parse_ipaddr(const char *cp,        const char **endp,
-                       u_int32_t *ipaddr, const char *limit)
+                       __be32 *ipaddr, const char *limit)
 {
        unsigned long int val;
        int i, digit = 0;
@@ -228,7 +240,7 @@ static int parse_ipaddr(const char *cp,     const char **endp,
 static int epaddr_len(const char *dptr, const char *limit, int *shift)
 {
        const char *aux = dptr;
-       u_int32_t ip;
+       __be32 ip;
 
        if (parse_ipaddr(dptr, &dptr, &ip, limit) < 0) {
                DEBUGP("ip: %s parse failed.!\n", dptr);
@@ -264,8 +276,9 @@ static int skp_epaddr_len(const char *dptr, const char *limit, int *shift)
 int ct_sip_get_info(const char *dptr, size_t dlen,
                    unsigned int *matchoff,
                    unsigned int *matchlen,
-                   struct sip_header_nfo *hnfo)
+                   enum sip_header_pos pos)
 {
+       struct sip_header_nfo *hnfo = &ct_sip_hdrs[pos];
        const char *limit, *aux, *k = dptr;
        int shift = 0;
 
@@ -278,7 +291,8 @@ int ct_sip_get_info(const char *dptr, size_t dlen,
                        continue;
                }
                aux = ct_sip_search(hnfo->ln_str, dptr, hnfo->ln_strlen,
-                                   ct_sip_lnlen(dptr, limit));
+                                   ct_sip_lnlen(dptr, limit),
+                                   hnfo->case_sensitive);
                if (!aux) {
                        DEBUGP("'%s' not found in '%s'.\n", hnfo->ln_str,
                               hnfo->lname);
@@ -299,16 +313,18 @@ int ct_sip_get_info(const char *dptr, size_t dlen,
        DEBUGP("%s header not found.\n", hnfo->lname);
        return 0;
 }
+EXPORT_SYMBOL_GPL(ct_sip_get_info);
 
 static int set_expected_rtp(struct sk_buff **pskb,
                            struct ip_conntrack *ct,
                            enum ip_conntrack_info ctinfo,
-                           u_int32_t ipaddr, u_int16_t port,
+                           __be32 ipaddr, u_int16_t port,
                            const char *dptr)
 {
        struct ip_conntrack_expect *exp;
        enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
        int ret;
+       typeof(ip_nat_sdp_hook) ip_nat_sdp;
 
        exp = ip_conntrack_expect_alloc(ct);
        if (exp == NULL)
@@ -320,17 +336,18 @@ static int set_expected_rtp(struct sk_buff **pskb,
        exp->tuple.dst.u.udp.port = htons(port);
        exp->tuple.dst.protonum = IPPROTO_UDP;
 
-       exp->mask.src.ip = 0xFFFFFFFF;
+       exp->mask.src.ip = htonl(0xFFFFFFFF);
        exp->mask.src.u.udp.port = 0;
-       exp->mask.dst.ip = 0xFFFFFFFF;
-       exp->mask.dst.u.udp.port = 0xFFFF;
+       exp->mask.dst.ip = htonl(0xFFFFFFFF);
+       exp->mask.dst.u.udp.port = htons(0xFFFF);
        exp->mask.dst.protonum = 0xFF;
 
        exp->expectfn = NULL;
        exp->flags = 0;
 
-       if (ip_nat_sdp_hook)
-               ret = ip_nat_sdp_hook(pskb, ctinfo, exp, dptr);
+       ip_nat_sdp = rcu_dereference(ip_nat_sdp_hook);
+       if (ip_nat_sdp)
+               ret = ip_nat_sdp(pskb, ctinfo, exp, dptr);
        else {
                if (ip_conntrack_expect_related(exp) != 0)
                        ret = NF_DROP;
@@ -350,8 +367,9 @@ static int sip_help(struct sk_buff **pskb,
        const char *dptr;
        int ret = NF_ACCEPT;
        int matchoff, matchlen;
-       u_int32_t ipaddr;
+       __be32 ipaddr;
        u_int16_t port;
+       typeof(ip_nat_sip_hook) ip_nat_sip;
 
        /* No Data ? */
        dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
@@ -369,8 +387,9 @@ static int sip_help(struct sk_buff **pskb,
                goto out;
        }
 
-       if (ip_nat_sip_hook) {
-               if (!ip_nat_sip_hook(pskb, ctinfo, ct, &dptr)) {
+       ip_nat_sip = rcu_dereference(ip_nat_sip_hook);
+       if (ip_nat_sip) {
+               if (!ip_nat_sip(pskb, ctinfo, ct, &dptr)) {
                        ret = NF_DROP;
                        goto out;
                }
@@ -390,7 +409,7 @@ static int sip_help(struct sk_buff **pskb,
        }
        /* Get ip and port address from SDP packet. */
        if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
-                           &ct_sip_hdrs[POS_CONNECTION]) > 0) {
+                           POS_CONNECTION) > 0) {
 
                /* We'll drop only if there are parse problems. */
                if (parse_ipaddr(dptr + matchoff, NULL, &ipaddr,
@@ -399,7 +418,7 @@ static int sip_help(struct sk_buff **pskb,
                        goto out;
                }
                if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
-                                   &ct_sip_hdrs[POS_MEDIA]) > 0) {
+                                   POS_MEDIA) > 0) {
 
                        port = simple_strtoul(dptr + matchoff, NULL, 10);
                        if (port < 1024) {
@@ -440,7 +459,7 @@ static int __init init(void)
 
                sip[i].tuple.dst.protonum = IPPROTO_UDP;
                sip[i].tuple.src.u.udp.port = htons(ports[i]);
-               sip[i].mask.src.u.udp.port = 0xFFFF;
+               sip[i].mask.src.u.udp.port = htons(0xFFFF);
                sip[i].mask.dst.protonum = 0xFF;
                sip[i].max_expected = 2;
                sip[i].timeout = 3 * 60; /* 3 minutes */
This page took 0.040805 seconds and 5 git commands to generate.