name mode size
..
doc 040000
Makefile 100644 255B
README 100644 5.35kB
common.h 100644 1.24kB
contact_ops.c 100644 18.72kB
contact_ops.h 100644 2.35kB
ip_helper.c 100644 5.84kB
ip_helper.h 100644 1.56kB
mangler.c 100644 6.4kB
mangler.cfg 100644 2.57kB
mangler.h 100644 1.37kB
sdp_mangler.c 100644 14.3kB
sdp_mangler.h 100644 3.02kB
utils.c 100644 3.13kB
utils.h 100644 1.99kB
README
The Mangler Module - SDP mangling Gabriel Vasile FhG FOKUS Copyright � 2003 FhG FOKUS _________________________________________________________________ Table of Contents 1. Admin Guide 1. Overview 2. Parameters 2.1. contact_flds_separator (string) 3. Functions 3.1. sdp_mangle_ip(pattern, newip) 3.2. sdp_mangle_port(offset) 3.3. encode_contact(encoding_prefix) 3.4. decode_contact() 3.5. decode_contact_header() List of Examples 1.1. Set db_url parameter 1.2. sdp_mangle_ip usage 1.3. sdp_mangle_port usage 1.4. encode_contact usage 1.5. decode_contact usage 1.6. decode_contact_header usage Chapter 1. Admin Guide Table of Contents 1. Overview 2. Parameters 2.1. contact_flds_separator (string) 3. Functions 3.1. sdp_mangle_ip(pattern, newip) 3.2. sdp_mangle_port(offset) 3.3. encode_contact(encoding_prefix) 3.4. decode_contact() 3.5. decode_contact_header() 1. Overview This is a module to help with SDP mangling - changing data in the SDP. 2. Parameters 2.1. contact_flds_separator (string) 2.1. contact_flds_separator (string) First char of this parameter is used as separator for encoding/decoding Contact header. If you set this parameter to "-", then an encoded uri might look sip:user-password-ip-port-protocol@PublicIP Warning First char of this field must be set to a value which is not used inside username,password or other fields of contact.Otherwise it is possible for the decoding step to fail/produce wrong results. Default value is "*". Example 1.1. Set db_url parameter ... modparam("mangler", "contact_flds_separator", "-") ... 3. Functions 3.1. sdp_mangle_ip(pattern, newip) 3.2. sdp_mangle_port(offset) 3.3. encode_contact(encoding_prefix) 3.4. decode_contact() 3.5. decode_contact_header() 3.1. sdp_mangle_ip(pattern, newip) Changes IP addresses inside SDP package in lines describing connections like c=IN IP4 . Currently this function only changes IP4 addresses since IP6 probably will not need to traverse NAT :) The function returns negative on error, or number of replacements + 1. Meaning of the parameters is as follows: * pattern - A ip address/mask pair used to match IP's located inside SDP package in lines c=IN IP4 ip. This line will only be changed if located IP is in the network described by this pattern. Examples of valid patterns are "10.0.0.0/255.0.0.0" or "10.0.0.0/8" etc. * newip - A string representing the new IP to be put inside SDP package if old IP address matches pattern. Example 1.2. sdp_mangle_ip usage ... sdp_mangle_ip("10.0.0.0/8","193.175.135.38"); ... 3.2. sdp_mangle_port(offset) Changes ports inside SDP package in lines describing media like m=audio 13451. The function returns negative on error, or number of replacements + 1. Meaning of the parameters is as follows: * offset - A string representing an integer which will be added/subtracted from the located port. Example 1.3. sdp_mangle_port usage ... sdp_mangle_port("-12000"); ... 3.3. encode_contact(encoding_prefix) This function will encode uri-s inside Contact header in the following manner sip:username:password@ip:port;transport=protocol goes sip:enc_pref*username*ip*port*protocol@public_ip. "*" (asterisk) is the default separator. The function returns negative on error, 1 on success. Meaning of the parameters is as follows: * encoding_prefix - Something to allow us to determine that a contact is encoded public ip--a routable IP, most probably you should put your external IP of your NAT box. Example 1.4. encode_contact usage ... if (src_ip == 10.0.0.0/8) encode_contact("enc_prefix","193.175.135.38"); ... 3.4. decode_contact() This function will decode the URI in first line in packets which come with encoded URI in the following manner sip:enc_pref*username*ip*port*protocol*src_ip*src_port*src_proto@publi c_ip;parameters is converted to sip:username:password@ip:port;parameters and will set destination URI to sip:src_ip:src_port;transport=src_proto (so that the next forward() or t_relay() will send the message back to src_ip:src_port using src_proto). It uses the default set parameter for contact encoding separator. The function returns negative on error, 1 on success. Example 1.5. decode_contact usage ... if (uri =~ "^enc*") { decode_contact(); } ... 3.5. decode_contact_header() This function will decode URIs inside Contact header in the same manner as decode_contact(). The difference is that no dst_uri is set (src_ip, src_port and src_proto are ignored) and instead of changing the request uri, the Contact header URI is modified. It uses the default set parameter for contact encoding separator. The function returns negative on error, 1 on success. Example 1.6. decode_contact_header usage ... if (uri =~ "^enc*") { decode_contact_header(); } ...