/*++ /* NAME /* peer_name 3 /* SUMMARY /* produce printable peer name and address /* SYNOPSIS /* #include <peer_name.h> /* /* typedef struct { /* .in +4 /* int type; /* char name; /* char addr; /* .in -4 /* } PEER_NAME; /* /* PEER_NAME *peer_name(sock) /* int sock; /* DESCRIPTION /* The \fIpeer_name\fR() routine attempts to produce a printable /* version of the peer name and address of the specified socket. /* The result is in static memory that will be overwritten. /* Make a copy if the result is to be used for an appreciable /* amount of time. /* /* Where information is unavailable, the name and/or address /* are set to "unknown". /* The \fItype\fR result field specifies how the name and address /* should be interpreted: /* .IP PEER_TYPE_INET /* The socket specifies a TCP/IP endpoint. /* The result is a hostname (from the DNS, a local hosts file or /* other); the address a dotted quad. /* .IP PEER_TYPE_LOCAL /* The socket argument specifies a local transport. /* The result name is "localhost"; the result address is "127.0.0.1". /* .IP PEER_TYPE_UNKNOWN /* The socket argument does not specify a socket. /* The result name is "localhost"; the result address is "127.0.0.1". /* LICENSE /* .ad /* .fi /* The Secure Mailer license must be distributed with this software. /* AUTHOR(S) /* Wietse Venema /* IBM T.J. Watson Research /* P.O. Box 704 /* Yorktown Heights, NY 10598, USA /*--*/ /* System library. */ #include <sys_defs.h> #include <sys/param.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <errno.h> #include <netdb.h> /* Utility library. */ #include <msg.h> #include <valid_hostname.h> #include <peer_name.h> /* peer_name - produce printable peer name and address */ PEER_NAME *peer_name(int sock) { static PEER_NAME peer; struct sockaddr_in sin; SOCKADDR_SIZE len = sizeof(sin); struct hostent *hp; if (getpeername(sock, (struct sockaddr *) & sin, &len) == 0) { switch (sin.sin_family) { case AF_INET: peer.type = PEER_TYPE_INET; hp = gethostbyaddr((char *) &(sin.sin_addr), sizeof(sin.sin_addr), AF_INET); peer.name = (hp && valid_hostname(hp->h_name, DO_GRIPE) ? hp->h_name : "unknown"); peer.addr = inet_ntoa(sin.sin_addr); return (&peer); case AF_UNSPEC: case AF_UNIX: peer.type = PEER_TYPE_LOCAL; peer.name = "localhost"; peer.addr = "127.0.0.1"; return (&peer); } } peer.type = PEER_TYPE_UNKNOWN; peer.name = "localhost"; peer.addr = "127.0.0.1"; return (&peer); } #ifdef TEST #include <unistd.h> int main(int unused_argc, char **unused_argv) { PEER_NAME *peer; peer = peer_name(STDIN_FILENO); msg_info("name %s addr %s", peer->name, peer->addr); } #endif