Initial version: May, 2000 (eds)
*/
+
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
int links_created = 0, pkt_updated = 0;
struct alias_link *rtsp_link = NULL;
struct in_addr null_addr;
-
+
/* Calculate data length of TCP packet */
tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
hlen = (pip->ip_hl + tc->th_off) << 2;
tlen = ntohs(pip->ip_len);
dlen = tlen - hlen;
-
+
+ if (dlen > sizeof(newdata)) {
+#if DEBUG
+ fprintf(stderr, "alias_rtsp_out: data len too big");
+#endif
+ return -1;
+ }
/* Find keyword, "Transport: " */
pos = search_string(data, dlen, transport_str);
if (pos < 0) {
- return -1;
+#if DEBUG
+ fprintf(stderr, "alias_rtsp_out: Transport not found");
+#endif
+ return -1;
}
+ if (pos >= sizeof(newdata)) {
+#if DEBUG
+ fprintf(stderr, "alias_rtsp_out: Transport too far");
+#endif
+ return -1;
+ }
port_data = data + pos;
port_dlen = dlen - pos;
-
+
memcpy(newdata, data, pos);
port_newdata = newdata + pos;
-
+
while (port_dlen > strlen(port_str)) {
- /* Find keyword, appropriate port string */
- pos = search_string(port_data, port_dlen, port_str);
- if (pos < 0) {
- break;
- }
-
- memcpy (port_newdata, port_data, pos + 1);
- port_newdata += (pos + 1);
-
- p[0] = p[1] = 0;
- sport = eport = 0;
- state = 0;
- for (i = pos; i < port_dlen; i++) {
- switch(state) {
- case 0:
- if (port_data[i] == '=') {
- state++;
- }
- break;
- case 1:
- if (ISDIGIT(port_data[i])) {
- p[0] = p[0] * 10 + port_data[i] - '0';
- } else {
- if (port_data[i] == ';') {
- state = 3;
- }
- if (port_data[i] == '-') {
- state++;
- }
- }
- break;
- case 2:
- if (ISDIGIT(port_data[i])) {
- p[1] = p[1] * 10 + port_data[i] - '0';
- } else {
- state++;
+ /* Find keyword, appropriate port string */
+ pos = search_string(port_data, port_dlen, port_str);
+ if (pos < 0 || port_data + pos + 1 > newdata + sizeof(newdata)) {
+#if DEBUG
+ fprintf(stderr, "alias_rtsp_out: port_str too far\n");
+#endif
+ break;
}
- break;
- case 3:
- base_port = p[0];
- sport = htons(p[0]);
- eport = htons(p[1]);
-
- if (!links_created) {
-
- links_created = 1;
- /* Find an even numbered port number base that
- satisfies the contiguous number of ports we need */
- null_addr.s_addr = 0;
- if (0 == (salias = FindNewPortGroup(null_addr,
- FindAliasAddress(pip->ip_src),
- sport, 0,
- RTSP_PORT_GROUP,
- IPPROTO_UDP, 1))) {
+
+ memcpy (port_newdata, port_data, pos + 1);
+ port_newdata += (pos + 1);
+
+ p[0] = p[1] = 0;
+ sport = eport = 0;
+ state = 0;
+ for (i = pos; i < port_dlen; i++) {
+ switch(state) {
+ case 0:
+ if (port_data[i] == '=') {
+ state++;
+ }
+ break;
+ case 1:
+ if (ISDIGIT(port_data[i])) {
+ p[0] = p[0] * 10 + port_data[i] - '0';
+ } else {
+ if (port_data[i] == ';') {
+ state = 3;
+ }
+ if (port_data[i] == '-') {
+ state++;
+ }
+ }
+ break;
+ case 2:
+ if (ISDIGIT(port_data[i])) {
+ p[1] = p[1] * 10 + port_data[i] - '0';
+ } else {
+ state++;
+ }
+ break;
+ case 3:
+ base_port = p[0];
+ sport = htons(p[0]);
+ eport = htons(p[1]);
+
+ if (!links_created) {
+
+ links_created = 1;
+ /* Find an even numbered port number base that
+ satisfies the contiguous number of ports we need */
+ null_addr.s_addr = 0;
+ if (0 == (salias = FindNewPortGroup(null_addr,
+ FindAliasAddress(pip->ip_src),
+ sport, 0,
+ RTSP_PORT_GROUP,
+ IPPROTO_UDP, 1))) {
#ifdef DEBUG
- fprintf(stderr,
- "PacketAlias/RTSP: Cannot find contiguous RTSP data ports\n");
+ fprintf(stderr,
+ "PacketAlias/RTSP: Cannot find contiguous RTSP data ports\n");
#endif
- } else {
-
- base_alias = ntohs(salias);
- for (j = 0; j < RTSP_PORT_GROUP; j++) {
- /* Establish link to port found in RTSP packet */
- rtsp_link = FindRtspOut(GetOriginalAddress(link), null_addr,
- htons(base_port + j), htons(base_alias + j),
- IPPROTO_UDP);
- if (rtsp_link != NULL) {
+ } else {
+
+ base_alias = ntohs(salias);
+ for (j = 0; j < RTSP_PORT_GROUP; j++) {
+ /* Establish link to port found in RTSP packet */
+ rtsp_link = FindRtspOut(GetOriginalAddress(link), null_addr,
+ htons(base_port + j), htons(base_alias + j),
+ IPPROTO_UDP);
+ if (rtsp_link != NULL) {
#ifndef NO_FW_PUNCH
- /* Punch hole in firewall */
- PunchFWHole(rtsp_link);
+ /* Punch hole in firewall */
+ PunchFWHole(rtsp_link);
#endif
- } else {
+ } else {
#ifdef DEBUG
- fprintf(stderr,
- "PacketAlias/RTSP: Cannot allocate RTSP data ports\n");
+ fprintf(stderr,
+ "PacketAlias/RTSP: Cannot allocate RTSP data ports\n");
#endif
- break;
- }
- }
- }
- ealias = htons(base_alias + (RTSP_PORT_GROUP - 1));
- }
-
- if (salias && rtsp_link) {
-
- pkt_updated = 1;
-
- /* Copy into IP packet */
- sprintf(stemp, "%d", ntohs(salias));
- memcpy(port_newdata, stemp, strlen(stemp));
- port_newdata += strlen(stemp);
-
- if (eport != 0) {
- *port_newdata = '-';
- port_newdata++;
-
- /* Copy into IP packet */
- sprintf(stemp, "%d", ntohs(ealias));
- memcpy(port_newdata, stemp, strlen(stemp));
- port_newdata += strlen(stemp);
- }
-
- *port_newdata = ';';
- port_newdata++;
+ break;
+ }
+ }
+ }
+ ealias = htons(base_alias + (RTSP_PORT_GROUP - 1));
+ }
+
+ if (salias && rtsp_link) {
+ size_t lentmp;
+
+ /* Copy into IP packet */
+ sprintf(stemp, "%d", ntohs(salias));
+ lentmp = strlen(stemp);
+ /* account for ending ';' */
+ if (port_newdata + lentmp + 1 > newdata + sizeof(newdata)) {
+#if DEBUG
+ fprintf(stderr, "PacketAlias/RTSP: salias too far\n");
+#endif
+ break;
+ }
+ memcpy(port_newdata, stemp, lentmp);
+ port_newdata += lentmp;
+
+ if (eport != 0) {
+ sprintf(stemp, "%d", ntohs(ealias));
+ lentmp = strlen(stemp);
+
+ /* account for middle '-' and for ending ';' */
+ if (port_newdata + lentmp + 2 > newdata + sizeof(newdata)) {
+#if DEBUG
+ fprintf(stderr, "PacketAlias/RTSP: ealias too far\n");
+#endif
+ break;
+ }
+ *port_newdata = '-';
+ port_newdata++;
+
+ /* Copy into IP packet */
+ memcpy(port_newdata, stemp, lentmp);
+ port_newdata += lentmp;
+ }
+ pkt_updated = 1;
+
+ *port_newdata = ';';
+ port_newdata++;
+ }
+ state++;
+ break;
+ }
+ if (state > 3) {
+ break;
+ }
}
- state++;
- break;
- }
- if (state > 3) {
- break;
- }
- }
- port_data += i;
- port_dlen -= i;
+ port_data += i;
+ port_dlen -= i;
}
-
- if (!pkt_updated)
- return -1;
-
+
+ if (!pkt_updated) {
+#if DEBUG
+ fprintf(stderr, "PacketAlias/RTSP: Packet not updated\n");
+#endif
+ return -1;
+ }
+
memcpy (port_newdata, port_data, port_dlen);
port_newdata += port_dlen;
*port_newdata = '\0';
-
+
/* Create new packet */
new_dlen = port_newdata - newdata;
memcpy (data, newdata, new_dlen);
-
+
SetAckModified(link);
delta = GetDeltaSeqOut(pip, link);
AddSeq(pip, link, delta + new_dlen - dlen);
-
+
new_len = htons(hlen + new_dlen);
DifferentialChecksum(&pip->ip_sum,
- &new_len,
- &pip->ip_len,
- 1);
+ &new_len,
+ &pip->ip_len,
+ 1);
pip->ip_len = new_len;
-
+
tc->th_sum = 0;
tc->th_sum = TcpChecksum(pip);
-
+
return 0;
}
projects / apple / network_cmds.git / commitdiff
