Reduce indentation and improve the readability of the code.
Signed-off-by: Jeremy Sowden <jeremy@xxxxxxxxxx>
---
extensions/xt_ipp2p.c | 332 ++++++++++++++++++++++--------------------
1 file changed, 171 insertions(+), 161 deletions(-)
diff --git a/extensions/xt_ipp2p.c b/extensions/xt_ipp2p.c
index f61f3f7cc2ee..16ee7f1ebb5c 100644
--- a/extensions/xt_ipp2p.c
+++ b/extensions/xt_ipp2p.c
@@ -199,12 +199,14 @@ static unsigned int udp_search_directconnect(const unsigned char *t,
{
if (packet_len < 5)
return 0;
- if (t[0] == 0x24 && t[packet_len-1] == 0x7c) {
- if (memcmp(&t[1], "SR ", 3) == 0)
- return IPP2P_DC * 100 + 60;
- if (packet_len >= 7 && memcmp(&t[1], "Ping ", 5) == 0)
- return IPP2P_DC * 100 + 61;
- }
+ if (t[0] != 0x24)
+ return 0;
+ if (t[packet_len-1] != 0x7c)
+ return 0;
+ if (memcmp(&t[1], "SR ", 3) == 0)
+ return IPP2P_DC * 100 + 60;
+ if (packet_len >= 7 && memcmp(&t[1], "Ping ", 5) == 0)
+ return IPP2P_DC * 100 + 61;
return 0;
}
@@ -263,12 +265,14 @@ udp_search_bit(const unsigned char *haystack, const unsigned int packet_len)
}
/* some extra-bitcomet rules: "d1:" [a|r] "d2:id20:" */
- if (packet_len > 22 && get_u8(haystack, 0) == 'd' &&
- get_u8(haystack, 1) == '1' && get_u8(haystack, 2) == ':')
- if (get_u8(haystack, 3) == 'a' ||
- get_u8(haystack, 3) == 'r')
- if (memcmp(haystack + 4, "d2:id20:", 8) == 0)
- return IPP2P_BIT * 100 + 57;
+ if (packet_len > 22 &&
+ get_u8(haystack, 0) == 'd' &&
+ get_u8(haystack, 1) == '1' &&
+ get_u8(haystack, 2) == ':' &&
+ (get_u8(haystack, 3) == 'a' ||
+ get_u8(haystack, 3) == 'r') &&
+ memcmp(haystack + 4, "d2:id20:", 8) == 0)
+ return IPP2P_BIT * 100 + 57;
#if 0
/* bitlord rules */
@@ -447,19 +451,22 @@ search_soul(const unsigned char *payload, const unsigned int plen)
/* without size at the beginning! */
if (get_u32(payload, 0) == 0x14 && get_u8(payload, 4) == 0x01) {
uint32_t y = get_u32(payload, 5);
+ const unsigned char *w;
/* we need 19 chars + string */
- if (y + 19 <= plen) {
- const unsigned char *w = payload + 9 + y;
- if (get_u32(w, 0) == 0x01 &&
- (get_u16(w, 4) == 0x4600 ||
- get_u16(w, 4) == 0x5000) &&
- get_u32(w, 6) == 0x00) {
+ if (plen < y + 19)
+ return 0;
+
+ w = payload + 9 + y;
+
+ if (get_u32(w, 0) == 0x01 &&
+ (get_u16(w, 4) == 0x4600 ||
+ get_u16(w, 4) == 0x5000) &&
+ get_u32(w, 6) == 0x00) {
#ifdef IPP2P_DEBUG_SOUL
- printk(KERN_DEBUG "Soulseek special client command recognized\n");
+ printk(KERN_DEBUG "Soulseek special client command recognized\n");
#endif
- return IPP2P_SOUL * 100 + 9;
- }
+ return IPP2P_SOUL * 100 + 9;
}
}
return 0;
@@ -523,10 +530,10 @@ search_winmx(const unsigned char *payload, const unsigned int plen)
static unsigned int
search_apple(const unsigned char *payload, const unsigned int plen)
{
- if (plen > 7 && iscrlf(&payload[6]) &&
- memcmp(payload, "ajprot", 6) == 0)
+ if (plen < 8)
+ return 0;
+ if (memcmp(payload, "ajprot\r\n", 8) == 0)
return IPP2P_APPLE * 100;
-
return 0;
}
@@ -534,41 +541,38 @@ search_apple(const unsigned char *payload, const unsigned int plen)
static unsigned int
search_bittorrent(const unsigned char *payload, const unsigned int plen)
{
- if (plen > 20) {
- /* test for match 0x13+"BitTorrent protocol" */
- if (payload[0] == 0x13)
- if (memcmp(payload + 1, "BitTorrent protocol", 19) == 0)
- return IPP2P_BIT * 100;
- /*
- * Any tracker command starts with GET / then *may be* some file on web server
- * (e.g. announce.php or dupa.pl or whatever.cgi or NOTHING for tracker on root dir)
- * but *must have* one (or more) of strings listed below (true for scrape and announce)
- */
- if (memcmp(payload, "GET /", 5) == 0) {
- if (HX_memmem(payload, plen, "info_hash=", 10) != NULL)
- return IPP2P_BIT * 100 + 1;
- if (HX_memmem(payload, plen, "peer_id=", 8) != NULL)
- return IPP2P_BIT * 100 + 2;
- if (HX_memmem(payload, plen, "passkey=", 8) != NULL)
- return IPP2P_BIT * 100 + 4;
- }
- } else {
- /* bitcomet encryptes the first packet, so we have to detect another
- * one later in the flow */
- /* first try failed, too many false positives */
- /*
- if (size == 5 && get_u32(t, 0) == __constant_htonl(1) &&
- t[4] < 3)
- return IPP2P_BIT * 100 + 3;
- */
+ /*
+ * bitcomet encrypts the first packet, so we have to detect another one
+ * later in the flow.
+ */
+ if (plen == 17 &&
+ get_u32(payload, 0) == __constant_htonl(0x0d) &&
+ payload[4] == 0x06 &&
+ get_u32(payload,13) == __constant_htonl(0x4000))
+ return IPP2P_BIT * 100 + 3;
- /* second try: block request packets */
- if (plen == 17 &&
- get_u32(payload, 0) == __constant_htonl(0x0d) &&
- payload[4] == 0x06 &&
- get_u32(payload,13) == __constant_htonl(0x4000))
- return IPP2P_BIT * 100 + 3;
- }
+ if (plen <= 20)
+ return 0;
+
+ /* test for match 0x13+"BitTorrent protocol" */
+ if (payload[0] == 0x13)
+ if (memcmp(payload + 1, "BitTorrent protocol", 19) == 0)
+ return IPP2P_BIT * 100;
+
+ /*
+ * Any tracker command starts with GET / then *may be* some file
+ * on web server (e.g. announce.php or dupa.pl or whatever.cgi
+ * or NOTHING for tracker on root dir) but *must have* one (or
+ * more) of strings listed below (true for scrape and announce)
+ */
+ if (memcmp(payload, "GET /", 5) != 0)
+ return 0;
+ if (HX_memmem(payload, plen, "info_hash=", 10) != NULL)
+ return IPP2P_BIT * 100 + 1;
+ if (HX_memmem(payload, plen, "peer_id=", 8) != NULL)
+ return IPP2P_BIT * 100 + 2;
+ if (HX_memmem(payload, plen, "passkey=", 8) != NULL)
+ return IPP2P_BIT * 100 + 4;
return 0;
}
@@ -592,12 +596,12 @@ search_gnu(const unsigned char *payload, const unsigned int plen)
{
if (plen < 11)
return 0;
- if (iscrlf(&payload[plen - 2])) {
- if (memcmp(payload, "GET /get/", 9) == 0)
- return IPP2P_DATA_GNU * 100 + 1;
- if (plen >= 15 && memcmp(payload, "GET /uri-res/", 13) == 0)
- return IPP2P_DATA_GNU * 100 + 2;
- }
+ if (!iscrlf(&payload[plen - 2]))
+ return 0;
+ if (memcmp(payload, "GET /get/", 9) == 0)
+ return IPP2P_DATA_GNU * 100 + 1;
+ if (plen >= 15 && memcmp(payload, "GET /uri-res/", 13) == 0)
+ return IPP2P_DATA_GNU * 100 + 2;
return 0;
}
@@ -605,25 +609,33 @@ search_gnu(const unsigned char *payload, const unsigned int plen)
static unsigned int
search_all_gnu(const unsigned char *payload, const unsigned int plen)
{
+ unsigned int c;
+
if (plen < 11)
return 0;
- if (iscrlf(&payload[plen - 2])) {
- if (plen >= 19 && memcmp(payload, "GNUTELLA CONNECT/", 17) == 0)
- return IPP2P_GNU * 100 + 1;
- if (memcmp(payload, "GNUTELLA/", 9) == 0)
- return IPP2P_GNU * 100 + 2;
-
- if (plen >= 22 && (memcmp(payload, "GET /get/", 9) == 0 ||
- memcmp(payload, "GET /uri-res/", 13) == 0))
- {
- unsigned int c;
+ if (!iscrlf(&payload[plen - 2]))
+ return 0;
+ if (plen >= 19 && memcmp(payload, "GNUTELLA CONNECT/", 17) == 0)
+ return IPP2P_GNU * 100 + 1;
+ if (memcmp(payload, "GNUTELLA/", 9) == 0)
+ return IPP2P_GNU * 100 + 2;
- for (c = 0; c < plen - 22; ++c)
- if (iscrlf(&payload[c]) &&
- (memcmp(&payload[c+2], "X-Gnutella-", 11) == 0 ||
- memcmp(&payload[c+2], "X-Queue:", 8) == 0))
- return IPP2P_GNU * 100 + 3;
- }
+ if (plen < 22)
+ return 0;
+
+ if (memcmp(payload, "GET /get/", 9) != 0 &&
+ memcmp(payload, "GET /uri-res/", 13) != 0)
+ return 0;
+
+ for (c = 0; c < plen - 22; ++c) {
+ if (!iscrlf(&payload[c]))
+ continue;
+
+ if (memcmp(&payload[c+2], "X-Gnutella-", 11) == 0)
+ return IPP2P_GNU * 100 + 3;
+
+ if ( memcmp(&payload[c+2], "X-Queue:", 8) == 0)
+ return IPP2P_GNU * 100 + 3;
}
return 0;
}
@@ -674,39 +686,37 @@ search_edk(const unsigned char *payload, const unsigned int plen)
{
if (plen < 6)
return 0;
- if (payload[0] != 0xe3) {
+ if (payload[0] != 0xe3)
return 0;
- } else {
- if (payload[5] == 0x47)
- return IPP2P_DATA_EDK * 100;
- else
- return 0;
- }
+ if (payload[5] == 0x47)
+ return IPP2P_DATA_EDK * 100;
+ return 0;
}
/* intensive but slower search for some eDonkey packets including size check */
static unsigned int
search_all_edk(const unsigned char *payload, const unsigned int plen)
{
+ unsigned int cmd;
+
if (plen < 6)
return 0;
- if (payload[0] != 0xe3) {
+ if (payload[0] != 0xe3)
return 0;
- } else {
- unsigned int cmd = get_u16(payload, 1);
- if (cmd == plen - 5) {
- switch (payload[5]) {
- case 0x01:
- /* Client: hello or Server:hello */
+ cmd = get_u16(payload, 1);
+
+ if (cmd == plen - 5) {
+ switch (payload[5]) {
+ case 0x01:
+ /* Client: hello or Server:hello */
return IPP2P_EDK * 100 + 1;
- case 0x4c:
- /* Client: Hello-Answer */
- return IPP2P_EDK * 100 + 9;
- }
+ case 0x4c:
+ /* Client: Hello-Answer */
+ return IPP2P_EDK * 100 + 9;
}
- return 0;
}
+ return 0;
}
/* fast check for Direct Connect send command */
@@ -715,36 +725,41 @@ search_dc(const unsigned char *payload, const unsigned int plen)
{
if (plen < 6)
return 0;
- if (payload[0] != 0x24) {
+ if (payload[0] != 0x24)
return 0;
- } else {
- if (memcmp(&payload[1], "Send|", 5) == 0)
- return IPP2P_DATA_DC * 100;
- else
- return 0;
- }
+ if (memcmp(&payload[1], "Send|", 5) == 0)
+ return IPP2P_DATA_DC * 100;
+ return 0;
}
/* intensive but slower check for all direct connect packets */
static unsigned int
search_all_dc(const unsigned char *payload, const unsigned int plen)
{
+ const unsigned char *t;
+
if (plen < 7)
return 0;
- if (payload[0] == 0x24 && payload[plen-1] == 0x7c) {
- const unsigned char *t = &payload[1];
- /* Client-Hub-Protocol */
- if (memcmp(t, "Lock ", 5) == 0)
- return IPP2P_DC * 100 + 1;
+ if (payload[0] != 0x24)
+ return 0;
+
+ if (payload[plen-1] != 0x7c)
+ return 0;
+
+ t = &payload[1];
+
+ /* Client-Hub-Protocol */
+ if (memcmp(t, "Lock ", 5) == 0)
+ return IPP2P_DC * 100 + 1;
+
+ /*
+ * Client-Client-Protocol, some are already recognized by client-hub
+ * (like lock)
+ */
+ if (plen >= 9 && memcmp(t, "MyNick ", 7) == 0)
+ return IPP2P_DC * 100 + 38;
- /*
- * Client-Client-Protocol, some are already recognized by
- * client-hub (like lock)
- */
- if (plen >= 9 && memcmp(t, "MyNick ", 7) == 0)
- return IPP2P_DC * 100 + 38;
- }
return 0;
}
@@ -770,23 +785,24 @@ search_mute(const unsigned char *payload, const unsigned int plen)
static unsigned int
search_xdcc(const unsigned char *payload, const unsigned int plen)
{
+ uint16_t x = 10;
+ const uint16_t end = plen - 13;
+
/* search in small packets only */
- if (plen > 20 && plen < 200 && iscrlf(&payload[plen - 2]) &&
- memcmp(payload, "PRIVMSG ", 8) == 0)
- {
- uint16_t x = 10;
- const uint16_t end = plen - 13;
+ if (plen <= 20 || plen >= 200)
+ return 0;
- /*
- * is seems to be an IRC private massage, check for
- * xdcc command
- */
- while (x < end) {
- if (payload[x] == ':')
- if (memcmp(&payload[x+1], "xdcc send #", 11) == 0)
- return IPP2P_XDCC * 100 + 0;
- x++;
- }
+ if (memcmp(payload, "PRIVMSG ", 8) != 0 || !iscrlf(&payload[plen - 2]))
+ return 0;
+
+ /*
+ * It seems to be an IRC private message, check for xdcc command
+ */
+ while (x < end) {
+ if (payload[x] == ':' &&
+ memcmp(&payload[x + 1], "xdcc send #", 11) == 0)
+ return IPP2P_XDCC * 100 + 0;
+ x++;
}
return 0;
}
@@ -862,8 +878,7 @@ ipp2p_mt_tcp(const struct ipt_p2p_info *info, const struct tcphdr *tcph,
const struct ipp2p_result_printer *rp)
{
size_t tcph_len = tcph->doff * 4;
- bool p2p_result = false;
- int i = 0;
+ int i;
if (tcph->fin) return 0; /* if FIN bit is set bail out */
if (tcph->syn) return 0; /* if SYN bit is set bail out */
@@ -880,20 +895,18 @@ ipp2p_mt_tcp(const struct ipt_p2p_info *info, const struct tcphdr *tcph,
haystack += tcph_len;
hlen -= tcph_len;
- while (matchlist[i].command) {
- if ((info->cmd & matchlist[i].command) == matchlist[i].command &&
- hlen > matchlist[i].packet_len)
- {
- p2p_result = matchlist[i].function_name(haystack, hlen);
- if (p2p_result) {
- if (info->debug)
- print_result(rp, p2p_result, hlen);
- return p2p_result;
- }
+ for (i = 0; matchlist[i].command; ++i) {
+ if ((info->cmd & matchlist[i].command) != matchlist[i].command)
+ continue;
+ if (hlen <= matchlist[i].packet_len)
+ continue;
+ if (matchlist[i].function_name(haystack, hlen)) {
+ if (info->debug)
+ print_result(rp, true, hlen);
+ return true;
}
- i++;
}
- return p2p_result;
+ return false;
}
static void
@@ -920,8 +933,7 @@ ipp2p_mt_udp(const struct ipt_p2p_info *info, const struct udphdr *udph,
const struct ipp2p_result_printer *rp)
{
size_t udph_len = sizeof(*udph);
- bool p2p_result = false;
- int i = 0;
+ int i;
if (hlen < udph_len) {
if (info->debug)
@@ -934,20 +946,18 @@ ipp2p_mt_udp(const struct ipt_p2p_info *info, const struct udphdr *udph,
haystack += udph_len;
hlen -= udph_len;
- while (udp_list[i].command) {
- if ((info->cmd & udp_list[i].command) == udp_list[i].command &&
- hlen > udp_list[i].packet_len)
- {
- p2p_result = udp_list[i].function_name(haystack, hlen);
- if (p2p_result) {
- if (info->debug)
- print_result(rp, p2p_result, hlen);
- return p2p_result;
- }
+ for (i = 0; udp_list[i].command; ++i) {
+ if ((info->cmd & udp_list[i].command) != udp_list[i].command)
+ continue;
+ if (hlen <= udp_list[i].packet_len)
+ continue;
+ if (udp_list[i].function_name(haystack, hlen)) {
+ if (info->debug)
+ print_result(rp, true, hlen);
+ return true;
}
- i++;
}
- return p2p_result;
+ return false;
}
static bool
--
2.39.2
