| 1 |  |  | /*	$OpenBSD: getnameinfo.c,v 1.8 2015/10/02 20:56:14 deraadt Exp $	*/ | 
    
    | 2 |  |  | /* | 
    
    | 3 |  |  |  * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> | 
    
    | 4 |  |  |  * | 
    
    | 5 |  |  |  * Permission to use, copy, modify, and distribute this software for any | 
    
    | 6 |  |  |  * purpose with or without fee is hereby granted, provided that the above | 
    
    | 7 |  |  |  * copyright notice and this permission notice appear in all copies. | 
    
    | 8 |  |  |  * | 
    
    | 9 |  |  |  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | 
    
    | 10 |  |  |  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | 
    
    | 11 |  |  |  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | 
    
    | 12 |  |  |  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | 
    
    | 13 |  |  |  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | 
    
    | 14 |  |  |  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | 
    
    | 15 |  |  |  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | 
    
    | 16 |  |  |  */ | 
    
    | 17 |  |  |  | 
    
    | 18 |  |  | #include <sys/types.h> | 
    
    | 19 |  |  | #include <sys/socket.h> | 
    
    | 20 |  |  | #include <net/if.h> | 
    
    | 21 |  |  | #include <arpa/inet.h> | 
    
    | 22 |  |  | #include <netinet/in.h> | 
    
    | 23 |  |  | #include <netdb.h> | 
    
    | 24 |  |  |  | 
    
    | 25 |  |  | #include <asr.h> | 
    
    | 26 |  |  | #include <errno.h> | 
    
    | 27 |  |  | #include <resolv.h> | 
    
    | 28 |  |  | #include <string.h> | 
    
    | 29 |  |  |  | 
    
    | 30 |  |  | static size_t asr_print_addr(const struct sockaddr *, char *, size_t); | 
    
    | 31 |  |  | static size_t asr_print_port(const struct sockaddr *, const char *, char *, size_t); | 
    
    | 32 |  |  |  | 
    
    | 33 |  |  | #define SA_IN(sa) ((struct sockaddr_in*)(sa)) | 
    
    | 34 |  |  | #define SA_IN6(sa) ((struct sockaddr_in6*)(sa)) | 
    
    | 35 |  |  |  | 
    
    | 36 |  |  | /* | 
    
    | 37 |  |  |  * Print the textual representation (as given by inet_ntop(3)) of the address | 
    
    | 38 |  |  |  * set in "sa". | 
    
    | 39 |  |  |  * | 
    
    | 40 |  |  |  * Return the total length of the string it tried to create or 0 if an error | 
    
    | 41 |  |  |  * occured, in which case errno is set.  On success, the constructed string | 
    
    | 42 |  |  |  * is guaranteed to be NUL-terminated.  Overflow must be detected by checking | 
    
    | 43 |  |  |  * the returned size against buflen. | 
    
    | 44 |  |  |  * | 
    
    | 45 |  |  |  */ | 
    
    | 46 |  |  | static size_t | 
    
    | 47 |  |  | asr_print_addr(const struct sockaddr *sa, char *buf, size_t buflen) | 
    
    | 48 |  |  | { | 
    
    | 49 |  |  | 	unsigned int ifidx; | 
    
    | 50 |  |  | 	char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")]; | 
    
    | 51 |  |  | 	char scope[IF_NAMESIZE + 1], *ifname; | 
    
    | 52 |  |  | 	const void *addr; | 
    
    | 53 |  |  | 	size_t s; | 
    
    | 54 |  |  |  | 
    
    | 55 |  |  | 	switch(sa->sa_family) { | 
    
    | 56 |  |  | 	case AF_INET: | 
    
    | 57 |  |  | 		addr = &SA_IN(sa)->sin_addr; | 
    
    | 58 |  |  | 		break; | 
    
    | 59 |  |  | 	case AF_INET6: | 
    
    | 60 |  |  | 		addr = &SA_IN6(sa)->sin6_addr; | 
    
    | 61 |  |  | 		break; | 
    
    | 62 |  |  | 	default: | 
    
    | 63 |  |  | 		errno = EINVAL; | 
    
    | 64 |  |  | 		return (0); | 
    
    | 65 |  |  | 	} | 
    
    | 66 |  |  |  | 
    
    | 67 |  |  | 	if (inet_ntop(sa->sa_family, addr, tmp, sizeof(tmp)) == NULL) | 
    
    | 68 |  |  | 		return (0); /* errno set */ | 
    
    | 69 |  |  |  | 
    
    | 70 |  |  | 	s = strlcpy(buf, tmp, buflen); | 
    
    | 71 |  |  |  | 
    
    | 72 |  |  | 	if (sa->sa_family == AF_INET6 && SA_IN6(sa)->sin6_scope_id) { | 
    
    | 73 |  |  |  | 
    
    | 74 |  |  | 		scope[0] = SCOPE_DELIMITER; | 
    
    | 75 |  |  | 		scope[1] = '\0'; | 
    
    | 76 |  |  |  | 
    
    | 77 |  |  | 		ifidx = SA_IN6(sa)->sin6_scope_id; | 
    
    | 78 |  |  | 		ifname = NULL; | 
    
    | 79 |  |  |  | 
    
    | 80 |  |  | 		if (IN6_IS_ADDR_LINKLOCAL(&(SA_IN6(sa)->sin6_addr)) || | 
    
    | 81 |  |  | 		    IN6_IS_ADDR_MC_LINKLOCAL(&(SA_IN6(sa)->sin6_addr)) || | 
    
    | 82 |  |  | 		    IN6_IS_ADDR_MC_INTFACELOCAL(&(SA_IN6(sa)->sin6_addr))) | 
    
    | 83 |  |  | 			ifname = if_indextoname(ifidx, scope + 1); | 
    
    | 84 |  |  |  | 
    
    | 85 |  |  | 		if (ifname == NULL) | 
    
    | 86 |  |  | 			(void)snprintf(scope + 1, sizeof(scope) - 1, "%u", ifidx); | 
    
    | 87 |  |  |  | 
    
    | 88 |  |  | 		if (s < buflen) | 
    
    | 89 |  |  | 			(void)strlcat(buf, scope, buflen); | 
    
    | 90 |  |  |  | 
    
    | 91 |  |  | 		s += strlen(scope); | 
    
    | 92 |  |  | 	} | 
    
    | 93 |  |  |  | 
    
    | 94 |  |  | 	return (s); | 
    
    | 95 |  |  | } | 
    
    | 96 |  |  |  | 
    
    | 97 |  |  | /* | 
    
    | 98 |  |  |  * Print the textual representation of the port set on "sa". | 
    
    | 99 |  |  |  * | 
    
    | 100 |  |  |  * If proto is not NULL, it is used as parameter to "getservbyport_r(3)" to | 
    
    | 101 |  |  |  * return a service name. If it's not set, or if no matching service is found, | 
    
    | 102 |  |  |  * it prints the portno. | 
    
    | 103 |  |  |  * | 
    
    | 104 |  |  |  * Return the total length of the string it tried to create or 0 if an error | 
    
    | 105 |  |  |  * occured, in which case errno is set.  On success, the constructed string | 
    
    | 106 |  |  |  * is guaranteed to be NUL-terminated.  Overflow must be detected by checking | 
    
    | 107 |  |  |  * the returned size against buflen. | 
    
    | 108 |  |  |  */ | 
    
    | 109 |  |  | static size_t | 
    
    | 110 |  |  | asr_print_port(const struct sockaddr *sa, const char *proto, char *buf, size_t buflen) | 
    
    | 111 |  |  | { | 
    
    | 112 |  |  | 	struct servent s; | 
    
    | 113 |  |  | 	struct servent_data sd; | 
    
    | 114 |  |  | 	int port, r, saved_errno; | 
    
    | 115 |  |  | 	size_t n; | 
    
    | 116 |  |  |  | 
    
    | 117 |  |  | 	switch(sa->sa_family) { | 
    
    | 118 |  |  | 	case AF_INET: | 
    
    | 119 |  |  | 		port = SA_IN(sa)->sin_port; | 
    
    | 120 |  |  | 		break; | 
    
    | 121 |  |  | 	case AF_INET6: | 
    
    | 122 |  |  | 		port = SA_IN6(sa)->sin6_port; | 
    
    | 123 |  |  | 		break; | 
    
    | 124 |  |  | 	default: | 
    
    | 125 |  |  | 		errno = EINVAL; | 
    
    | 126 |  |  | 		return (0); | 
    
    | 127 |  |  | 	} | 
    
    | 128 |  |  |  | 
    
    | 129 |  |  | 	if (proto) { | 
    
    | 130 |  |  | 		memset(&sd, 0, sizeof (sd)); | 
    
    | 131 |  |  | 		saved_errno = errno; | 
    
    | 132 |  |  | 		if (getservbyport_r(port, proto, &s, &sd) != -1) { | 
    
    | 133 |  |  | 			n = strlcpy(buf, s.s_name, buflen); | 
    
    | 134 |  |  | 			endservent_r(&sd); | 
    
    | 135 |  |  | 			return (n); | 
    
    | 136 |  |  | 		} | 
    
    | 137 |  |  | 		errno = saved_errno; | 
    
    | 138 |  |  | 	} | 
    
    | 139 |  |  |  | 
    
    | 140 |  |  | 	r = snprintf(buf, buflen, "%u", ntohs(port)); | 
    
    | 141 |  |  | 	if (r == -1) 	/* Actually, this can not happen */ | 
    
    | 142 |  |  | 		return (0); | 
    
    | 143 |  |  |  | 
    
    | 144 |  |  | 	return (r); | 
    
    | 145 |  |  | } | 
    
    | 146 |  |  |  | 
    
    | 147 |  |  | int | 
    
    | 148 |  |  | getnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, | 
    
    | 149 |  |  |     size_t hostlen, char *serv, size_t servlen, int flags) | 
    
    | 150 |  |  | { | 
    
    | 151 |  |  | 	struct asr_query *as; | 
    
    | 152 |  |  | 	struct asr_result ar; | 
    
    | 153 |  |  | 	int saved_errno = errno; | 
    
    | 154 |  |  | 	const char *proto; | 
    
    | 155 |  |  | 	size_t r; | 
    
    | 156 |  |  |  | 
    
    | 157 |  |  | 	/* | 
    
    | 158 |  |  | 	 * Take a shortcut if we don't care about hostname, | 
    
    | 159 |  |  | 	 * or if NI_NUMERICHOST is set. | 
    
    | 160 |  |  | 	 */ | 
    
    | 161 |  |  | 	if (host == NULL || hostlen == 0 || | 
    
    | 162 |  |  | 	    (host && hostlen && (flags & NI_NUMERICHOST))) { | 
    
    | 163 |  |  | 		if (host) { | 
    
    | 164 |  |  | 			r = asr_print_addr(sa, host, hostlen); | 
    
    | 165 |  |  | 			if (r == 0) | 
    
    | 166 |  |  | 				return (EAI_SYSTEM); /* errno set */ | 
    
    | 167 |  |  | 			if (r >= hostlen) | 
    
    | 168 |  |  | 				return (EAI_OVERFLOW); | 
    
    | 169 |  |  | 		} | 
    
    | 170 |  |  |  | 
    
    | 171 |  |  | 		if (serv && servlen) { | 
    
    | 172 |  |  | 			if (flags & NI_NUMERICSERV) | 
    
    | 173 |  |  | 				proto = NULL; | 
    
    | 174 |  |  | 			else | 
    
    | 175 |  |  | 				proto = (flags & NI_DGRAM) ? "udp" : "tcp"; | 
    
    | 176 |  |  | 			r = asr_print_port(sa, proto, serv, servlen); | 
    
    | 177 |  |  | 			if (r == 0) | 
    
    | 178 |  |  | 				return (EAI_SYSTEM); /* errno set */ | 
    
    | 179 |  |  | 			if (r >= servlen) | 
    
    | 180 |  |  | 				return (EAI_OVERFLOW); | 
    
    | 181 |  |  | 		} | 
    
    | 182 |  |  |  | 
    
    | 183 |  |  | 		errno = saved_errno; | 
    
    | 184 |  |  | 		return (0); | 
    
    | 185 |  |  | 	} | 
    
    | 186 |  |  |  | 
    
    | 187 |  |  | 	res_init(); | 
    
    | 188 |  |  |  | 
    
    | 189 |  |  | 	as = getnameinfo_async(sa, salen, host, hostlen, serv, servlen, flags, | 
    
    | 190 |  |  | 	    NULL); | 
    
    | 191 |  |  | 	if (as == NULL) { | 
    
    | 192 |  |  | 		if (errno == ENOMEM) { | 
    
    | 193 |  |  | 			errno = saved_errno; | 
    
    | 194 |  |  | 			return (EAI_MEMORY); | 
    
    | 195 |  |  | 		} | 
    
    | 196 |  |  | 		return (EAI_SYSTEM); | 
    
    | 197 |  |  | 	} | 
    
    | 198 |  |  |  | 
    
    | 199 |  |  | 	asr_run_sync(as, &ar); | 
    
    | 200 |  |  | 	if (ar.ar_gai_errno == EAI_SYSTEM) | 
    
    | 201 |  |  | 		errno = ar.ar_errno; | 
    
    | 202 |  |  |  | 
    
    | 203 |  |  | 	return (ar.ar_gai_errno); | 
    
    | 204 |  |  | } | 
    
    | 205 |  |  | DEF_WEAK(getnameinfo); |