1 /* $NetBSD: canohost.c,v 1.16 2023/10/25 20:19:57 christos Exp $ */ 2 /* $OpenBSD: canohost.c,v 1.77 2023/03/31 04:42:29 dtucker Exp $ */ 3 4 /* 5 * Author: Tatu Ylonen <ylo@cs.hut.fi> 6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 7 * All rights reserved 8 * Functions for returning the canonical host name of the remote site. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 */ 16 17 #include "includes.h" 18 __RCSID("$NetBSD: canohost.c,v 1.16 2023/10/25 20:19:57 christos Exp $"); 19 #include <sys/types.h> 20 #include <sys/socket.h> 21 #include <sys/un.h> 22 23 #include <netinet/in.h> 24 25 #include <errno.h> 26 #include <netdb.h> 27 #include <stdio.h> 28 #include <stdlib.h> 29 #include <string.h> 30 #include <stdarg.h> 31 #include <time.h> 32 #include <unistd.h> 33 34 #include "xmalloc.h" 35 #include "packet.h" 36 #include "log.h" 37 #include "canohost.h" 38 #include "misc.h" 39 40 /* 41 * Returns the local/remote IP-address/hostname of socket as a string. 42 * The returned string must be freed. 43 */ 44 static char * 45 get_socket_address(int sock, int remote, int flags) 46 { 47 struct sockaddr_storage addr; 48 socklen_t addrlen; 49 char ntop[NI_MAXHOST]; 50 int r; 51 52 if (sock < 0) 53 return NULL; 54 55 /* Get IP address of client. */ 56 addrlen = sizeof(addr); 57 memset(&addr, 0, sizeof(addr)); 58 59 if (remote) { 60 if (getpeername(sock, (struct sockaddr *)&addr, &addrlen) != 0) 61 return NULL; 62 } else { 63 if (getsockname(sock, (struct sockaddr *)&addr, &addrlen) != 0) 64 return NULL; 65 } 66 67 switch (addr.ss_family) { 68 case AF_INET: 69 case AF_INET6: 70 /* Get the address in ascii. */ 71 if ((r = getnameinfo((struct sockaddr *)&addr, addrlen, ntop, 72 sizeof(ntop), NULL, 0, flags)) != 0) { 73 error_f("getnameinfo %d failed: %s", 74 flags, ssh_gai_strerror(r)); 75 return NULL; 76 } 77 return xstrdup(ntop); 78 case AF_UNIX: 79 /* Get the Unix domain socket path. */ 80 return xstrdup(((struct sockaddr_un *)&addr)->sun_path); 81 default: 82 /* We can't look up remote Unix domain sockets. */ 83 return NULL; 84 } 85 } 86 87 char * 88 get_peer_ipaddr(int sock) 89 { 90 char *p; 91 92 if ((p = get_socket_address(sock, 1, NI_NUMERICHOST)) != NULL) 93 return p; 94 return xstrdup("UNKNOWN"); 95 } 96 97 char * 98 get_local_ipaddr(int sock) 99 { 100 char *p; 101 102 if ((p = get_socket_address(sock, 0, NI_NUMERICHOST)) != NULL) 103 return p; 104 return xstrdup("UNKNOWN"); 105 } 106 107 char * 108 get_local_name(int fd) 109 { 110 char *host, myname[NI_MAXHOST]; 111 112 /* Assume we were passed a socket */ 113 if ((host = get_socket_address(fd, 0, NI_NAMEREQD)) != NULL) 114 return host; 115 116 /* Handle the case where we were passed a pipe */ 117 if (gethostname(myname, sizeof(myname)) == -1) { 118 verbose_f("gethostname: %s", strerror(errno)); 119 host = xstrdup("UNKNOWN"); 120 } else { 121 host = xstrdup(myname); 122 } 123 124 return host; 125 } 126 127 /* Returns the local/remote port for the socket. */ 128 129 static int 130 get_sock_port(int sock, int local) 131 { 132 struct sockaddr_storage from; 133 socklen_t fromlen; 134 char strport[NI_MAXSERV]; 135 int r; 136 137 if (sock < 0) 138 return -1; 139 /* Get IP address of client. */ 140 fromlen = sizeof(from); 141 memset(&from, 0, sizeof(from)); 142 if (local) { 143 if (getsockname(sock, (struct sockaddr *)&from, &fromlen) == -1) { 144 error("getsockname failed: %.100s", strerror(errno)); 145 return 0; 146 } 147 } else { 148 if (getpeername(sock, (struct sockaddr *)&from, &fromlen) == -1) { 149 debug("getpeername failed: %.100s", strerror(errno)); 150 return -1; 151 } 152 } 153 154 /* Non-inet sockets don't have a port number. */ 155 if (from.ss_family != AF_INET && from.ss_family != AF_INET6) 156 return 0; 157 158 /* Return port number. */ 159 if ((r = getnameinfo((struct sockaddr *)&from, fromlen, NULL, 0, 160 strport, sizeof(strport), NI_NUMERICSERV)) != 0) 161 fatal_f("getnameinfo NI_NUMERICSERV failed: %s", 162 ssh_gai_strerror(r)); 163 return atoi(strport); 164 } 165 166 int 167 get_peer_port(int sock) 168 { 169 return get_sock_port(sock, 0); 170 } 171 172 int 173 get_local_port(int sock) 174 { 175 return get_sock_port(sock, 1); 176 } 177