基于用户地址编址方式的 操作系统原型设计与实现

1、User-Oriented Addressing(Operating System Implementation),overnitary 2007.4,Operating System supports,UNIX-like OS for planetary computing assigns addresses to users constrains use of owned address only limits users view for interface and routes Our Approach New socket layer in the kernel insert use

2、r-address mapping examination in several kernel functions or system calls Relative Work ULN (User Layer Network),Relative Work,Based on kernel patch of ULN But we modified on: A different Data Structure and ioctl Interface Allow Multi-Mapping of user to address Cancel the privilege limitation of the

3、 usage of ports num1024 Transport to a new version of kernel Fix the bugs of original patch,Kernel Modification,Address Usage Checking To do user checking in several socket functions to block unauthorized address usage. Data structure and ioctl Interface To provides an user interface for super user

4、to adjust the user-address mapping.,TCP UOA checking At connect() for clients At bind() for servers,UDP UOA checking At bind() At sendmsg(),Address Usage Checking: IPv4,uoa_inet_autobind() Blocks autobind(), so actually blocks unbound connect (UDP) and unbound sendmsg (TCP,UDP) uoa_inet_bind() Block

5、s bind (TCP,UDP) uoa_tcp_connect() Blocks connect (TCP) uoa_raw_sendmsg() Blocks sendmsg (ICMP) uoa_raw_bind() Blocks bind (ICMP),Address Usage Checking: IPv6,uoa_ipv6_get_saddr() Most important one. It affect the selection of source address, so it affect unbound connect (UDP) and unbound sendmsg (T

6、CP,UDP,ICMP) uoa_inet6_bind() Blocks bind (TCP,UDP) uoa_tcp_v6_connect() Blocks connect (TCP) uoa_rawv6_bind() Blocks bind (ICMP),Data Structure,Maintain a user-address mapping link list. Both v4 and v6 version are alike. int insert_ip4_token(struct in_addr * addr, uid_t uid); Returns 1 if success,

7、-ERR. if error int check_ip4_token(struct in_addr * addr, uid_t uid); Returns 3 if a mapping of addr-uid exists. 2 if the user has mapping to other addresses, 1 if the address has mapping to other users, 0 if none of above. struct ip4_token *find_ip4_token(uid_t uid); Returns a mapping token of curr

8、ent uid uid_t find_ip4_token_uidbyaddr(struct in_addr *addr); Returns the uid of an exist mapping of addr, for the compatibility of ULN apps. int delete_all_ip4_tokens_byaddr(struct in_addr * addr); int delete_all_ip4_tokens_byusr(uid_t uid); int delete_ip4_token(struct in_addr * addr, uid_t uid); R

9、eturns the number of mapping token deleted, -ERR if error void print_ip4_tokens(void);,Ioctl Interface,Link to certain data structure control functions. SIOCAUOAMAP: insert_ip4_token SIOCGUOAMAP: find_ip4_token_uidbyaddr SIOCCUOAMAP: check_ip4_token SIOCDUOAMAP:delete_ip4_token SIOCUOADUSR:delete_al

10、l_ip4_tokens_byusr SIOCUOADADDR:delete_all_ip4_tokens_byaddr,Example,Now with the super user having assigned two different addresses for 2 normal users, both of them can set up a httpd server on *:80.,Contributions,Present a Problem for Architecture: Will the user-address mapping be 1-1, 1-n, n-1, o

11、r n-n? How about Loopback Addresses, Local Addresses and Multicast Address?,Further Work,To Build a intact Operating System Prototype, we still need to make: Configuration Tools To Let the system to be a distributable version, we still need to fix: The * binding problem Communication with user mode applications with /proc files,* binding problem,There are 2 types of address for a socket to bind: a certain address and * In current version of UOA,