| |
| /* Copyright 2005 by Dominick Meglio |
| * |
| * Permission to use, copy, modify, and distribute this |
| * software and its documentation for any purpose and without |
| * fee is hereby granted, provided that the above copyright |
| * notice appear in all copies and that both that copyright |
| * notice and this permission notice appear in supporting |
| * documentation, and that the name of M.I.T. not be used in |
| * advertising or publicity pertaining to distribution of the |
| * software without specific, written prior permission. |
| * M.I.T. makes no representations about the suitability of |
| * this software for any purpose. It is provided "as is" |
| * without express or implied warranty. |
| */ |
| #include "ares_setup.h" |
| |
| #ifdef HAVE_GETSERVBYPORT_R |
| # if !defined(GETSERVBYPORT_R_ARGS) || \ |
| (GETSERVBYPORT_R_ARGS < 4) || (GETSERVBYPORT_R_ARGS > 6) |
| # error "you MUST specifiy a valid number of arguments for getservbyport_r" |
| # endif |
| #endif |
| |
| #ifdef HAVE_SYS_SOCKET_H |
| # include <sys/socket.h> |
| #endif |
| #ifdef HAVE_NETINET_IN_H |
| # include <netinet/in.h> |
| #endif |
| #ifdef HAVE_NETDB_H |
| # include <netdb.h> |
| #endif |
| #ifdef HAVE_ARPA_INET_H |
| # include <arpa/inet.h> |
| #endif |
| #ifdef HAVE_ARPA_NAMESER_H |
| # include <arpa/nameser.h> |
| #else |
| # include "nameser.h" |
| #endif |
| #ifdef HAVE_ARPA_NAMESER_COMPAT_H |
| # include <arpa/nameser_compat.h> |
| #endif |
| |
| #ifdef HAVE_NET_IF_H |
| #include <net/if.h> |
| #endif |
| |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "ares.h" |
| #include "ares_ipv6.h" |
| #include "inet_ntop.h" |
| #include "ares_nowarn.h" |
| #include "ares_private.h" |
| |
| struct nameinfo_query { |
| ares_nameinfo_callback callback; |
| void *arg; |
| union { |
| struct sockaddr_in addr4; |
| struct sockaddr_in6 addr6; |
| } addr; |
| int family; |
| int flags; |
| int timeouts; |
| }; |
| |
| #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID |
| #define IPBUFSIZ \ |
| (sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255") + IF_NAMESIZE) |
| #else |
| #define IPBUFSIZ \ |
| (sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")) |
| #endif |
| |
| static void nameinfo_callback(void *arg, int status, int timeouts, |
| struct hostent *host); |
| static char *lookup_service(unsigned short port, int flags, |
| char *buf, size_t buflen); |
| #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID |
| static void append_scopeid(struct sockaddr_in6 *addr6, unsigned int scopeid, |
| char *buf, size_t buflen); |
| #endif |
| static char *ares_striendstr(const char *s1, const char *s2); |
| |
| void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, |
| ares_socklen_t salen, |
| int flags, ares_nameinfo_callback callback, void *arg) |
| { |
| struct sockaddr_in *addr = NULL; |
| struct sockaddr_in6 *addr6 = NULL; |
| struct nameinfo_query *niquery; |
| unsigned int port = 0; |
| |
| /* Validate socket address family and length */ |
| if ((sa->sa_family == AF_INET) && |
| (salen == sizeof(struct sockaddr_in))) |
| { |
| addr = (struct sockaddr_in *)sa; |
| port = addr->sin_port; |
| } |
| else if ((sa->sa_family == AF_INET6) && |
| (salen == sizeof(struct sockaddr_in6))) |
| { |
| addr6 = (struct sockaddr_in6 *)sa; |
| port = addr6->sin6_port; |
| } |
| else |
| { |
| callback(arg, ARES_ENOTIMP, 0, NULL, NULL); |
| return; |
| } |
| |
| /* If neither, assume they want a host */ |
| if (!(flags & ARES_NI_LOOKUPSERVICE) && !(flags & ARES_NI_LOOKUPHOST)) |
| flags |= ARES_NI_LOOKUPHOST; |
| |
| /* All they want is a service, no need for DNS */ |
| if ((flags & ARES_NI_LOOKUPSERVICE) && !(flags & ARES_NI_LOOKUPHOST)) |
| { |
| char buf[33], *service; |
| |
| service = lookup_service((unsigned short)(port & 0xffff), |
| flags, buf, sizeof(buf)); |
| callback(arg, ARES_SUCCESS, 0, NULL, service); |
| return; |
| } |
| |
| /* They want a host lookup */ |
| if ((flags & ARES_NI_LOOKUPHOST)) |
| { |
| /* A numeric host can be handled without DNS */ |
| if ((flags & ARES_NI_NUMERICHOST)) |
| { |
| char ipbuf[IPBUFSIZ]; |
| char srvbuf[33]; |
| char *service = NULL; |
| ipbuf[0] = 0; |
| |
| /* Specifying not to lookup a host, but then saying a host |
| * is required has to be illegal. |
| */ |
| if (flags & ARES_NI_NAMEREQD) |
| { |
| callback(arg, ARES_EBADFLAGS, 0, NULL, NULL); |
| return; |
| } |
| if (salen == sizeof(struct sockaddr_in6)) |
| { |
| ares_inet_ntop(AF_INET6, &addr6->sin6_addr, ipbuf, IPBUFSIZ); |
| /* If the system supports scope IDs, use it */ |
| #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID |
| append_scopeid(addr6, flags, ipbuf, sizeof(ipbuf)); |
| #endif |
| } |
| else |
| { |
| ares_inet_ntop(AF_INET, &addr->sin_addr, ipbuf, IPBUFSIZ); |
| } |
| /* They also want a service */ |
| if (flags & ARES_NI_LOOKUPSERVICE) |
| service = lookup_service((unsigned short)(port & 0xffff), |
| flags, srvbuf, sizeof(srvbuf)); |
| callback(arg, ARES_SUCCESS, 0, ipbuf, service); |
| return; |
| } |
| /* This is where a DNS lookup becomes necessary */ |
| else |
| { |
| niquery = malloc(sizeof(struct nameinfo_query)); |
| if (!niquery) |
| { |
| callback(arg, ARES_ENOMEM, 0, NULL, NULL); |
| return; |
| } |
| niquery->callback = callback; |
| niquery->arg = arg; |
| niquery->flags = flags; |
| niquery->timeouts = 0; |
| if (sa->sa_family == AF_INET) |
| { |
| niquery->family = AF_INET; |
| memcpy(&niquery->addr.addr4, addr, sizeof(struct in_addr)); |
| ares_gethostbyaddr(channel, &addr->sin_addr, |
| sizeof(struct in_addr), AF_INET, |
| nameinfo_callback, niquery); |
| } |
| else |
| { |
| niquery->family = AF_INET6; |
| memcpy(&niquery->addr.addr6, addr6, sizeof(struct ares_in6_addr)); |
| ares_gethostbyaddr(channel, &addr6->sin6_addr, |
| sizeof(struct ares_in6_addr), AF_INET6, |
| nameinfo_callback, niquery); |
| } |
| } |
| } |
| } |
| |
| static void nameinfo_callback(void *arg, int status, int timeouts, |
| struct hostent *host) |
| { |
| struct nameinfo_query *niquery = (struct nameinfo_query *) arg; |
| char srvbuf[33]; |
| char *service = NULL; |
| |
| niquery->timeouts += timeouts; |
| if (status == ARES_SUCCESS) |
| { |
| /* They want a service too */ |
| if (niquery->flags & ARES_NI_LOOKUPSERVICE) |
| { |
| if (niquery->family == AF_INET) |
| service = lookup_service(niquery->addr.addr4.sin_port, |
| niquery->flags, srvbuf, sizeof(srvbuf)); |
| else |
| service = lookup_service(niquery->addr.addr6.sin6_port, |
| niquery->flags, srvbuf, sizeof(srvbuf)); |
| } |
| /* NOFQDN means we have to strip off the domain name portion. We do |
| this by determining our own domain name, then searching the string |
| for this domain name and removing it. |
| */ |
| #ifdef HAVE_GETHOSTNAME |
| if (niquery->flags & ARES_NI_NOFQDN) |
| { |
| char buf[255]; |
| char *domain; |
| gethostname(buf, 255); |
| if ((domain = strchr(buf, '.')) != NULL) |
| { |
| char *end = ares_striendstr(host->h_name, domain); |
| if (end) |
| *end = 0; |
| } |
| } |
| #endif |
| niquery->callback(niquery->arg, ARES_SUCCESS, niquery->timeouts, |
| (char *)(host->h_name), |
| service); |
| free(niquery); |
| return; |
| } |
| /* We couldn't find the host, but it's OK, we can use the IP */ |
| else if (status == ARES_ENOTFOUND && !(niquery->flags & ARES_NI_NAMEREQD)) |
| { |
| char ipbuf[IPBUFSIZ]; |
| if (niquery->family == AF_INET) |
| ares_inet_ntop(AF_INET, &niquery->addr.addr4.sin_addr, ipbuf, |
| IPBUFSIZ); |
| else |
| { |
| ares_inet_ntop(AF_INET6, &niquery->addr.addr6.sin6_addr, ipbuf, |
| IPBUFSIZ); |
| #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID |
| append_scopeid(&niquery->addr.addr6, niquery->flags, ipbuf, |
| sizeof(ipbuf)); |
| #endif |
| } |
| /* They want a service too */ |
| if (niquery->flags & ARES_NI_LOOKUPSERVICE) |
| { |
| if (niquery->family == AF_INET) |
| service = lookup_service(niquery->addr.addr4.sin_port, |
| niquery->flags, srvbuf, sizeof(srvbuf)); |
| else |
| service = lookup_service(niquery->addr.addr6.sin6_port, |
| niquery->flags, srvbuf, sizeof(srvbuf)); |
| } |
| niquery->callback(niquery->arg, ARES_SUCCESS, niquery->timeouts, ipbuf, |
| service); |
| free(niquery); |
| return; |
| } |
| niquery->callback(niquery->arg, status, niquery->timeouts, NULL, NULL); |
| free(niquery); |
| } |
| |
| static char *lookup_service(unsigned short port, int flags, |
| char *buf, size_t buflen) |
| { |
| const char *proto; |
| struct servent *sep; |
| #ifdef HAVE_GETSERVBYPORT_R |
| struct servent se; |
| #endif |
| char tmpbuf[4096]; |
| |
| if (port) |
| { |
| if (flags & ARES_NI_NUMERICSERV) |
| sep = NULL; |
| else |
| { |
| if (flags & ARES_NI_UDP) |
| proto = "udp"; |
| else if (flags & ARES_NI_SCTP) |
| proto = "sctp"; |
| else if (flags & ARES_NI_DCCP) |
| proto = "dccp"; |
| else |
| proto = "tcp"; |
| #ifdef HAVE_GETSERVBYPORT_R |
| sep = &se; |
| memset(tmpbuf, 0, sizeof(tmpbuf)); |
| #if GETSERVBYPORT_R_ARGS == 6 |
| if (getservbyport_r(port, proto, &se, (void *)tmpbuf, |
| sizeof(tmpbuf), &sep) != 0) |
| sep = NULL; |
| #elif GETSERVBYPORT_R_ARGS == 5 |
| sep = getservbyport_r(port, proto, &se, (void *)tmpbuf, |
| sizeof(tmpbuf)); |
| #elif GETSERVBYPORT_R_ARGS == 4 |
| if (getservbyport_r(port, proto, &se, (void *)tmpbuf) != 0) |
| sep = NULL; |
| #else |
| /* Lets just hope the OS uses TLS! */ |
| sep = getservbyport(port, proto); |
| #endif |
| #else |
| /* Lets just hope the OS uses TLS! */ |
| #if (defined(NETWARE) && !defined(__NOVELL_LIBC__)) |
| sep = getservbyport(port, (char*)proto); |
| #else |
| sep = getservbyport(port, proto); |
| #endif |
| #endif |
| } |
| if (sep && sep->s_name) |
| /* get service name */ |
| strcpy(tmpbuf, sep->s_name); |
| else |
| /* get port as a string */ |
| sprintf(tmpbuf, "%u", (unsigned int)ntohs(port)); |
| if (strlen(tmpbuf) < buflen) |
| /* return it if buffer big enough */ |
| strcpy(buf, tmpbuf); |
| else |
| /* avoid reusing previous one */ |
| buf[0] = '\0'; |
| return buf; |
| } |
| buf[0] = '\0'; |
| return NULL; |
| } |
| |
| #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID |
| static void append_scopeid(struct sockaddr_in6 *addr6, unsigned int flags, |
| char *buf, size_t buflen) |
| { |
| #ifdef HAVE_IF_INDEXTONAME |
| int is_ll, is_mcll; |
| #endif |
| static const char fmt_u[] = "%u"; |
| static const char fmt_lu[] = "%lu"; |
| char tmpbuf[IF_NAMESIZE + 2]; |
| size_t bufl; |
| const char *fmt = (sizeof(addr6->sin6_scope_id) > sizeof(unsigned int))? |
| fmt_lu:fmt_u; |
| |
| tmpbuf[0] = '%'; |
| |
| #ifdef HAVE_IF_INDEXTONAME |
| is_ll = IN6_IS_ADDR_LINKLOCAL(&addr6->sin6_addr); |
| is_mcll = IN6_IS_ADDR_MC_LINKLOCAL(&addr6->sin6_addr); |
| if ((flags & ARES_NI_NUMERICSCOPE) || |
| (!is_ll && !is_mcll)) |
| { |
| sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); |
| } |
| else |
| { |
| if (if_indextoname(addr6->sin6_scope_id, &tmpbuf[1]) == NULL) |
| sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); |
| } |
| #else |
| sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); |
| (void) flags; |
| #endif |
| tmpbuf[IF_NAMESIZE + 1] = '\0'; |
| bufl = strlen(buf); |
| |
| if(bufl + strlen(tmpbuf) < buflen) |
| /* only append the scopeid string if it fits in the target buffer */ |
| strcpy(&buf[bufl], tmpbuf); |
| } |
| #endif |
| |
| /* Determines if s1 ends with the string in s2 (case-insensitive) */ |
| static char *ares_striendstr(const char *s1, const char *s2) |
| { |
| const char *c1, *c2, *c1_begin; |
| int lo1, lo2; |
| size_t s1_len = strlen(s1), s2_len = strlen(s2); |
| |
| /* If the substr is longer than the full str, it can't match */ |
| if (s2_len > s1_len) |
| return NULL; |
| |
| /* Jump to the end of s1 minus the length of s2 */ |
| c1_begin = s1+s1_len-s2_len; |
| c1 = (const char *)c1_begin; |
| c2 = s2; |
| while (c2 < s2+s2_len) |
| { |
| lo1 = TOLOWER(*c1); |
| lo2 = TOLOWER(*c2); |
| if (lo1 != lo2) |
| return NULL; |
| else |
| { |
| c1++; |
| c2++; |
| } |
| } |
| if (c2 == c1 && c2 == NULL) |
| return (char *)c1_begin; |
| return NULL; |
| } |
