diff options
Diffstat (limited to 'inet/getnameinfo.c')
| -rw-r--r-- | inet/getnameinfo.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/inet/getnameinfo.c b/inet/getnameinfo.c new file mode 100644 index 0000000000..b9454f6396 --- /dev/null +++ b/inet/getnameinfo.c @@ -0,0 +1,238 @@ +/* The Inner Net License, Version 2.00 + + The author(s) grant permission for redistribution and use in source and +binary forms, with or without modification, of the software and documentation +provided that the following conditions are met: + +0. If you receive a version of the software that is specifically labelled + as not being for redistribution (check the version message and/or README), + you are not permitted to redistribute that version of the software in any + way or form. +1. All terms of the all other applicable copyrights and licenses must be + followed. +2. Redistributions of source code must retain the authors' copyright + notice(s), this list of conditions, and the following disclaimer. +3. Redistributions in binary form must reproduce the authors' copyright + notice(s), this list of conditions, and the following disclaimer in the + documentation and/or other materials provided with the distribution. +4. All advertising materials mentioning features or use of this software + must display the following acknowledgement with the name(s) of the + authors as specified in the copyright notice(s) substituted where + indicated: + + This product includes software developed by <name(s)>, The Inner + Net, and other contributors. + +5. Neither the name(s) of the author(s) nor the names of its contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY ITS AUTHORS AND CONTRIBUTORS ``AS IS'' AND ANY +EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY +DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON +ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + If these license terms cause you a real problem, contact the author. */ + +/* This software is Copyright 1996 by Craig Metz, All Rights Reserved. */ + +#define INET6 1 +#define LOCAL 1 +#define HOSTTABLE 0 + +#include <sys/types.h> +#include <sys/socket.h> + +#include <netinet/in.h> +#if LOCAL +#include <sys/un.h> +#include <sys/utsname.h> +#endif /* LOCAL */ +#include <netdb.h> +#include <errno.h> +#include <string.h> +#include <stdio.h> +#include <unistd.h> + +#ifndef AF_LOCAL +#define AF_LOCAL AF_UNIX +#endif /* AF_LOCAL */ + +#if HOSTTABLE +struct hostent *_addr2hostname_hosts(const char *, int, int); +#endif /* HOSTTABLE */ + +#ifndef MAXHOSTNAMELEN +#define MAXHOSTNAMELEN 128 +#endif + +#ifndef min +#define min(x,y) (((x) > (y)) ? (y) : (x)) +#endif /* min */ + +static char *domain; +static char domainbuffer[MAXHOSTNAMELEN]; + + +static char * +nrl_domainname (void) +{ + static int first = 1; + + if (first) { + char *c; + struct hostent *h; + + first = 0; + + if ((h = gethostbyname("localhost")) && (c = strchr(h->h_name, '.'))) + return strcpy(domain = domainbuffer, ++c); + + if (!gethostname(domainbuffer, sizeof(domainbuffer))) { + if (c = strchr(domainbuffer, '.')) + return (domain = ++c); + + if ((h = gethostbyname(domainbuffer)) && (c = strchr(h->h_name, '.'))) + return strcpy(domain = domainbuffer, ++c); + } + + { + struct in_addr in_addr; + + in_addr.s_addr = htonl(0x7f000001); + + if ((h = gethostbyaddr((const char *)&in_addr, sizeof(struct in_addr), AF_INET)) && (c = strchr(h->h_name, '.'))) + return strcpy(domain = domainbuffer, ++c); + } + + return NULL; + }; + + return domain; +}; + +int getnameinfo(const struct sockaddr *sa, size_t addrlen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) +{ + int serrno = errno; + + if (!sa) + return -1; + + if (host && (hostlen > 0)) + switch(sa->sa_family) { + case AF_INET: +#if INET6 + case AF_INET6: +#endif /* INET6 */ + if (!(flags & NI_NUMERICHOST)) { + struct hostent *h = NULL; +#if HOSTTABLE +#if INET6 + if (sa->sa_family == AF_INET6) + h = _addr2hostname_hosts((void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), sizeof(struct in6_addr), AF_INET6); + else +#endif /* INET6 */ + h = _addr2hostname_hosts((void *)&(((struct sockaddr_in *)sa)->sin_addr), sizeof(struct in_addr), AF_INET); +#endif /* HOSTTABLE */ + +#if RESOLVER + if (!h) { +#if INET6 + if (sa->sa_family == AF_INET6) + h = gethostbyaddr((void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), sizeof(struct in6_addr), AF_INET6); + else +#endif /* INET6 */ + h = gethostbyaddr((void *)&(((struct sockaddr_in *)sa)->sin_addr), sizeof(struct in_addr), AF_INET); + endhostent(); + }; +#endif /* RESOLVER */ + + if (h) { + if (flags & NI_NOFQDN) { + char *c; + if ((c = nrl_domainname()) && (c = strstr(h->h_name, c)) && (c != h->h_name) && (*(--c) == '.')) { + strncpy(host, h->h_name, min(hostlen, (c - h->h_name))); + break; + }; + }; + strncpy(host, h->h_name, hostlen); + break; + }; + }; + + if (flags & NI_NAMEREQD) + goto fail; + + { + const char *c; +#if INET6 + if (sa->sa_family == AF_INET6) + c = inet_ntop(AF_INET6, (void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), host, hostlen); + else +#endif /* INET6 */ + c = inet_ntop(AF_INET, (void *)&(((struct sockaddr_in *)sa)->sin_addr), host, hostlen); + + if (!c) + goto fail; + }; + break; +#if LOCAL + case AF_LOCAL: + if (!(flags & NI_NUMERICHOST)) { + struct utsname utsname; + + if (!uname(&utsname)) { + strncpy(host, utsname.nodename, hostlen); + break; + }; + }; + + if (flags & NI_NAMEREQD) + goto fail; + + strncpy(host, "localhost", hostlen); + break; +#endif /* LOCAL */ + default: + return -1; + }; + + if (serv && (servlen > 0)) + switch(sa->sa_family) { + case AF_INET: +#if INET6 + case AF_INET6: +#endif /* INET6 */ + if (!(flags & NI_NUMERICSERV)) { + struct servent *s; + if (s = getservbyport(((struct sockaddr_in *)sa)->sin_port, (flags & NI_DGRAM) ? "udp" : "tcp")) { + strncpy(serv, s->s_name, servlen); + break; + }; + }; + snprintf(serv, servlen, "%d", ntohs(((struct sockaddr_in *)sa)->sin_port)); + break; +#if LOCAL + case AF_LOCAL: + strncpy(serv, ((struct sockaddr_un *)sa)->sun_path, servlen); + break; +#endif /* LOCAL */ + }; + + if (host && (hostlen > 0)) + host[hostlen-1] = 0; + if (serv && (servlen > 0)) + serv[servlen-1] = 0; + errno = serrno; + return 0; + +fail: + errno = serrno; + return -1; +}; |