Initial version

1 files changed, 203 insertions, 0 deletions

diff --git a/src/network/getnameinfo.c b/src/network/getnameinfo.c
new file mode 100644
index 0000000..133c15b
--- /dev/null
+++ b/src/network/getnameinfo.c
@@ -0,0 +1,203 @@
+#include <netdb.h>
+#include <limits.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <ctype.h>
+#include <resolv.h>
+#include "lookup.h"
+#include "stdio_impl.h"
+
+#define PTR_MAX (64 + sizeof ".in-addr.arpa")
+#define RR_PTR 12
+
+static char *itoa(char *p, unsigned x) {
+	p += 3*sizeof(int);
+	*--p = 0;
+	do {
+		*--p = '0' + x % 10;
+		x /= 10;
+	} while (x);
+	return p;
+}
+
+static void mkptr4(char *s, const unsigned char *ip)
+{
+	sprintf(s, "%d.%d.%d.%d.in-addr.arpa",
+		ip[3], ip[2], ip[1], ip[0]);
+}
+
+static void mkptr6(char *s, const unsigned char *ip)
+{
+	static const char xdigits[] = "0123456789abcdef";
+	int i;
+	for (i=15; i>=0; i--) {
+		*s++ = xdigits[ip[i]&15]; *s++ = '.';
+		*s++ = xdigits[ip[i]>>4]; *s++ = '.';
+	}
+	strcpy(s, "ip6.arpa");
+}
+
+static void reverse_hosts(char *buf, const unsigned char *a, unsigned scopeid, int family)
+{
+	char line[512], *p, *z;
+	unsigned char _buf[1032], atmp[16];
+	struct address iplit;
+	FILE _f, *f = __fopen_rb_ca("/etc/hosts", &_f, _buf, sizeof _buf);
+	if (!f) return;
+	if (family == AF_INET) {
+		memcpy(atmp+12, a, 4);
+		memcpy(atmp, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
+		a = atmp;
+	}
+	while (fgets(line, sizeof line, f)) {
+		if ((p=strchr(line, '#'))) *p++='\n', *p=0;
+
+		for (p=line; *p && !isspace(*p); p++);
+		if (!*p) continue;
+		*p++ = 0;
+		if (__lookup_ipliteral(&iplit, line, AF_UNSPEC)<=0)
+			continue;
+
+		if (iplit.family == AF_INET) {
+			memcpy(iplit.addr+12, iplit.addr, 4);
+			memcpy(iplit.addr, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
+			iplit.scopeid = 0;
+		}
+
+		if (memcmp(a, iplit.addr, 16) || iplit.scopeid != scopeid)
+			continue;
+			
+		for (; *p && isspace(*p); p++);
+		for (z=p; *z && !isspace(*z); z++);
+		*z = 0;
+		if (z-p < 256) {
+			memcpy(buf, p, z-p+1);
+			break;
+		}
+	}
+	__fclose_ca(f);
+}
+
+static void reverse_services(char *buf, int port, int dgram)
+{
+	unsigned long svport;
+	char line[128], *p, *z;
+	unsigned char _buf[1032];
+	FILE _f, *f = __fopen_rb_ca("/etc/services", &_f, _buf, sizeof _buf);
+	if (!f) return;
+	while (fgets(line, sizeof line, f)) {
+		if ((p=strchr(line, '#'))) *p++='\n', *p=0;
+
+		for (p=line; *p && !isspace(*p); p++);
+		if (!*p) continue;
+		*p++ = 0;
+		svport = strtoul(p, &z, 10);
+
+		if (svport != port || z==p) continue;
+		if (dgram && strncmp(z, "/udp", 4)) continue;
+		if (!dgram && strncmp(z, "/tcp", 4)) continue;
+		if (p-line > 32) continue;
+
+		memcpy(buf, line, p-line);
+		break;
+	}
+	__fclose_ca(f);
+}
+
+static int dns_parse_callback(void *c, int rr, const void *data, int len, const void *packet, int plen)
+{
+	if (rr != RR_PTR) return 0;
+	if (__dn_expand(packet, (const unsigned char *)packet + plen,
+	    data, c, 256) <= 0)
+		*(char *)c = 0;
+	return 0;
+	
+}
+
+int getnameinfo(const struct sockaddr *restrict sa, socklen_t sl,
+	char *restrict node, socklen_t nodelen,
+	char *restrict serv, socklen_t servlen,
+	int flags)
+{
+	char ptr[PTR_MAX];
+	char buf[256], num[3*sizeof(int)+1];
+	int af = sa->sa_family;
+	unsigned char *a;
+	unsigned scopeid;
+
+	switch (af) {
+	case AF_INET:
+		a = (void *)&((struct sockaddr_in *)sa)->sin_addr;
+		if (sl < sizeof(struct sockaddr_in)) return EAI_FAMILY;
+		mkptr4(ptr, a);
+		scopeid = 0;
+		break;
+	case AF_INET6:
+		a = (void *)&((struct sockaddr_in6 *)sa)->sin6_addr;
+		if (sl < sizeof(struct sockaddr_in6)) return EAI_FAMILY;
+		if (memcmp(a, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12))
+			mkptr6(ptr, a);
+		else
+			mkptr4(ptr, a+12);
+		scopeid = ((struct sockaddr_in6 *)sa)->sin6_scope_id;
+		break;
+	default:
+		return EAI_FAMILY;
+	}
+
+	if (node && nodelen) {
+		buf[0] = 0;
+		if (!(flags & NI_NUMERICHOST)) {
+			reverse_hosts(buf, a, scopeid, af);
+		}
+		if (!*buf && !(flags & NI_NUMERICHOST)) {
+			unsigned char query[18+PTR_MAX], reply[512];
+			int qlen = __res_mkquery(0, ptr, 1, RR_PTR,
+				0, 0, 0, query, sizeof query);
+			query[3] = 0; /* don't need AD flag */
+			int rlen = __res_send(query, qlen, reply, sizeof reply);
+			buf[0] = 0;
+			if (rlen > 0) {
+				if (rlen > sizeof reply) rlen = sizeof reply;
+				__dns_parse(reply, rlen, dns_parse_callback, buf);
+			}
+		}
+		if (!*buf) {
+			if (flags & NI_NAMEREQD) return EAI_NONAME;
+			inet_ntop(af, a, buf, sizeof buf);
+			if (scopeid) {
+				char *p = 0, tmp[IF_NAMESIZE+1];
+				if (!(flags & NI_NUMERICSCOPE) &&
+				    (IN6_IS_ADDR_LINKLOCAL(a) ||
+				     IN6_IS_ADDR_MC_LINKLOCAL(a)))
+					p = if_indextoname(scopeid, tmp+1);
+				if (!p)
+					p = itoa(num, scopeid);
+				*--p = '%';
+				strcat(buf, p);
+			}
+		}
+		if (strlen(buf) >= nodelen) return EAI_OVERFLOW;
+		strcpy(node, buf);
+	}
+
+	if (serv && servlen) {
+		char *p = buf;
+		int port = ntohs(((struct sockaddr_in *)sa)->sin_port);
+		buf[0] = 0;
+		if (!(flags & NI_NUMERICSERV))
+			reverse_services(buf, port, flags & NI_DGRAM);
+		if (!*p)
+			p = itoa(num, port);
+		if (strlen(p) >= servlen)
+			return EAI_OVERFLOW;
+		strcpy(serv, p);
+	}
+
+	return 0;
+}