1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * Shim library which should be LD_PRELOADed before running applications 30 * that interact with NCA but do not explicitly use the AF_NCA family. 31 * This library overloads AF_INET's version of bind(3SOCKET) with AF_NCA's 32 * version. The new version of bind checks to see if that the port is one 33 * NCA is listening on, closes the socket(3SOCKET), and opens a new one 34 * the family AF_NCA. Afterwards, the real bind(3SOCKET) is called 35 * descriptors, etc. * 36 * 37 * Compile: cc -Kpic -G -o ncad_addr.so ncad_addr.c -lsocket -lnsl 38 * Use: LD_PRELOAD=/path/to/ncad_addr.so my_program 39 */ 40 41 #include <stdio.h> 42 #include <assert.h> 43 #include <dlfcn.h> 44 #include <door.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <inet/nd.h> 48 #include <unistd.h> 49 #include <stropts.h> 50 #include <sys/stat.h> 51 #include <string.h> 52 #include <stdlib.h> 53 #include <sys/mman.h> 54 #include <netdb.h> 55 #include <ctype.h> 56 #include <sys/types.h> 57 #include <sys/socket.h> 58 #include <netinet/in.h> 59 #include <arpa/inet.h> 60 61 #pragma weak bind = nca_bind 62 #pragma init(ncad_init) 63 #pragma fini(ncad_fini) 64 65 #define SEPARATOR '/' 66 67 typedef int sfunc1_t(int, int, int); 68 typedef int sfunc2_t(int, const struct sockaddr *, socklen_t); 69 70 static sfunc1_t *real_socket; 71 static sfunc2_t *real_bind; 72 73 /* 74 * It is used to represent an address NCA is willing to handle. 75 */ 76 typedef struct nca_address_s { 77 uint16_t port; /* port, in network byte order */ 78 ipaddr_t ipaddr; /* IP address, in network byte order */ 79 } nca_address_t; 80 81 static uint32_t addrcount; /* current address count */ 82 static uint32_t addrcapacity; /* capacity of ncaaddrs */ 83 static nca_address_t *ncaaddrs; /* array for all addresses */ 84 85 /* 86 * It loads all NCA addresses from a configuration file. A NCA address 87 * entry is: ncaport=IPaddress:port. The line above can be repeatly for other 88 * addresses. If IPaddress is '*', then it is translated into INADDR_ANY. 89 */ 90 static void 91 ncad_init(void) 92 { 93 uint16_t port; 94 ipaddr_t addr; 95 FILE *fp; 96 char *s, *p, *q; 97 char buffer[1024]; 98 const char *filename = "/etc/nca/ncaport.conf"; 99 100 real_socket = (sfunc1_t *)dlsym(RTLD_NEXT, "socket"); 101 real_bind = (sfunc2_t *)dlsym(RTLD_NEXT, "bind"); 102 103 if ((fp = fopen(filename, "rF")) == NULL) { 104 (void) fprintf(stderr, "Failed to open file %s for reading in " 105 " ncad_addr.so. Error = %s\n", 106 filename, 107 (p = strerror(errno)) ? p : "unknown error"); 108 return; 109 } 110 111 while (fgets(buffer, sizeof (buffer), fp) != NULL) { 112 s = buffer; 113 114 /* remove '\n' at the end from fgets() */ 115 p = strchr(s, '\n'); 116 if (p != NULL) 117 *p = '\0'; 118 119 /* remove spaces from the front */ 120 while (*s != '\0' && isspace(*s)) 121 s++; 122 123 if (*s == '\0' || *s == '#') 124 continue; 125 126 /* it should start with ncaport= */ 127 p = strchr(s, '='); 128 if (p == NULL || strncasecmp(s, "ncaport", 7) != 0) 129 continue; 130 131 p++; 132 while (*p != '\0' && isspace(*p)) 133 p++; 134 135 q = strchr(p, SEPARATOR); 136 if (q == NULL) 137 continue; 138 *q++ = '\0'; 139 if (strcmp(p, "*") == 0) { 140 addr = INADDR_ANY; 141 } else { 142 if (inet_pton(AF_INET, p, &addr) != 1) { 143 struct in6_addr addr6; 144 145 if (inet_pton(AF_INET6, p, &addr6) == 1) { 146 (void) fprintf(stderr, 147 "NCA does not support IPv6\n"); 148 } else { 149 (void) fprintf(stderr, 150 "Invalid IP address: %s\n", p); 151 } 152 continue; 153 } 154 } 155 port = atoi(q); 156 157 /* array is full, expand it */ 158 if (addrcount == addrcapacity) { 159 if (addrcapacity == 0) 160 addrcapacity = 64; 161 else 162 addrcapacity *= 2; 163 ncaaddrs = realloc(ncaaddrs, 164 addrcapacity * sizeof (nca_address_t)); 165 if (ncaaddrs == NULL) { 166 (void) fprintf(stderr, "out of memory"); 167 break; 168 } 169 } 170 171 ncaaddrs[addrcount].ipaddr = addr; 172 ncaaddrs[addrcount].port = htons(port); 173 addrcount++; 174 } 175 176 (void) fclose(fp); 177 } 178 179 /* 180 * It destroys memory at the end of program. 181 */ 182 static void 183 ncad_fini(void) 184 { 185 if (ncaaddrs != NULL) { 186 free(ncaaddrs); 187 ncaaddrs = NULL; 188 } 189 } 190 191 /* 192 * If the bind is happening on a port NCA is listening on, close 193 * the socket and open a new one with family AF_NCA. 194 */ 195 static int 196 nca_bind(int sock, const struct sockaddr *name, socklen_t namelen) 197 { 198 struct sockaddr_in sin; 199 int new_sock; 200 int i; 201 202 if (sock < 0) { 203 errno = EBADF; 204 return (-1); 205 } 206 207 if (real_socket == NULL) { 208 if ((real_socket = (sfunc1_t *)dlsym(RTLD_NEXT, "socket")) 209 == NULL) { 210 errno = EAGAIN; 211 exit(-1); 212 } 213 } 214 215 if (real_bind == NULL) { 216 if ((real_bind = (sfunc2_t *)dlsym(RTLD_NEXT, "bind")) 217 == NULL) { 218 errno = EAGAIN; 219 exit(-1); 220 } 221 } 222 223 if (name == NULL || 224 ncaaddrs == NULL || 225 name->sa_family != AF_INET || 226 namelen != sizeof (sin)) { 227 return (real_bind(sock, name, namelen)); 228 } 229 230 (void) memcpy(&sin, name, sizeof (sin)); 231 232 /* 233 * If it is one of the addresses NCA is handling, convert it 234 * to NCA socket. 235 */ 236 for (i = 0; i < addrcount; i++) { 237 if (sin.sin_port == ncaaddrs[i].port && 238 (sin.sin_addr.s_addr == ncaaddrs[i].ipaddr || 239 ncaaddrs[i].ipaddr == INADDR_ANY)) { 240 /* convert to NCA socket */ 241 new_sock = real_socket(AF_NCA, SOCK_STREAM, 0); 242 if (new_sock >= 0) { 243 (void) dup2(new_sock, sock); 244 (void) close(new_sock); 245 sin.sin_family = AF_NCA; 246 } 247 break; 248 } 249 } 250 251 return (real_bind(sock, (struct sockaddr *)&sin, namelen)); 252 } 253