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-rw-r--r--libc/inet/resolv.c261
1 files changed, 230 insertions, 31 deletions
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c
index 38aa9b272..d02d29fbc 100644
--- a/libc/inet/resolv.c
+++ b/libc/inet/resolv.c
@@ -49,6 +49,7 @@
#include <cfgfile.h>
#include <resolv.h>
#include <netdb.h>
+#include <ctype.h>
#include <arpa/nameser.h>
#define MAX_RECURSE 5
@@ -59,16 +60,20 @@
#undef DEBUG
#ifdef DEBUG
-static inline void DPRINTF(const char *format, ...)
-{
- va_list args;
- va_start(args, format);
- vfprintf(stderr, format, args);
- va_end(args);
-}
+#define DPRINTF(X,args...) fprintf(stderr, X, ##args)
#else
-static inline void DPRINTF(const char *format, ...) { }
-#endif
+#define DPRINTF(X,args...)
+#endif /* DEBUG */
+
+
+extern int nameservers;
+extern const char * nameserver[MAX_SERVERS];
+extern int searchdomains;
+extern const char * searchdomain[MAX_SEARCH];
+extern struct hostent * get_hosts_byname(const char * name);
+extern struct hostent * get_hosts_byaddr(const char * addr, int len, int type);
+extern struct hostent * read_etc_hosts(const char * name, int ip);
+
#ifdef L_encodeh
int encode_header(struct resolv_header *h, unsigned char *dest, int maxlen)
@@ -461,8 +466,6 @@ int dns_lookup(const char *name, int type, int nscount, const char **nsip,
unsigned char * packet = malloc(PACKETSZ);
unsigned char * lookup = malloc(MAXDNAME);
int variant = 0;
- extern int searchdomains;
- extern const char * searchdomain[MAX_SEARCH];
fd = -1;
@@ -753,10 +756,6 @@ int resolve_mailbox(const char *address,
}
#endif
-extern int nameservers;
-extern const char * nameserver[MAX_SERVERS];
-extern int searchdomains;
-extern const char * searchdomain[MAX_SEARCH];
#ifdef L_opennameservers
@@ -765,26 +764,57 @@ const char * nameserver[MAX_SERVERS];
int searchdomains;
const char * searchdomain[MAX_SEARCH];
+/*
+ * we currently read formats not quite the same as that on normal
+ * unix systems, we can have a list of nameservers after the keyword.
+ */
+
int open_nameservers()
{
FILE *fp;
- char **arg;
int i;
+#define RESOLV_ARGS 5
+ char szBuffer[128], *p, *argv[RESOLV_ARGS];
+ int argc;
if (nameservers > 0)
return 0;
- if ((fp = fopen("/etc/resolv.conf", "r"))) {
- if (0 != (arg = cfgfind(fp, "nameserver"))) {
- for (i=1; arg[i] && nameservers <= MAX_SERVERS; i++) {
- nameserver[nameservers++] = strdup(arg[i]);
- DPRINTF("adding nameserver %s\n",arg[i]);
+ if ((fp = fopen("/etc/resolv.conf", "r")) ||
+ (fp = fopen("/etc/config/resolv.conf", "r"))) {
+
+ while (fgets(szBuffer, sizeof(szBuffer), fp) != NULL) {
+
+ for (p = szBuffer; *p && isspace(*p); p++)
+ /* skip white space */;
+ if (*p == '\0' || *p == '\n' || *p == '#') /* skip comments etc */
+ continue;
+ argc = 0;
+ while (*p && argc < RESOLV_ARGS) {
+ argv[argc++] = p;
+ while (*p && !isspace(*p) && *p != '\n')
+ p++;
+ while (*p && (isspace(*p) || *p == '\n')) /* remove spaces */
+ *p++ = '\0';
+ }
+
+ if (strcmp(argv[0], "nameserver") == 0) {
+ for (i = 1; i < argc && nameservers < MAX_SERVERS; i++) {
+ nameserver[nameservers++] = strdup(argv[i]);
+ DPRINTF("adding nameserver %s\n", argv[i]);
+ }
}
- }
- if (0 != (arg = cfgfind(fp, "search"))) {
- for (i=1; arg[i] && searchdomains <= MAX_SEARCH; i++) {
- searchdomain[searchdomains++] = strdup(arg[i]);
- DPRINTF("adding search %s\n",arg[i]);
+
+ /* domain and search are mutually exclusive, the last one wins */
+ if (strcmp(argv[0],"domain")==0 || strcmp(argv[0],"search")==0) {
+ while (searchdomains > 0) {
+ free(searchdomain[--searchdomains]);
+ searchdomain[searchdomains] = NULL;
+ }
+ for (i=1; i < argc && searchdomains < MAX_SEARCH; i++) {
+ searchdomain[searchdomains++] = strdup(argv[i]);
+ DPRINTF("adding search %s\n", argv[i]);
+ }
}
}
fclose(fp);
@@ -796,12 +826,19 @@ int open_nameservers()
}
#endif
+
#ifdef L_closenameservers
+
void close_nameservers(void)
{
-
- while (nameservers > 0)
- free((void*)nameserver[--nameservers]);
+ while (nameservers > 0) {
+ free(nameserver[--nameservers]);
+ nameserver[nameservers] = NULL;
+ }
+ while (searchdomains > 0) {
+ free(searchdomain[--searchdomains]);
+ searchdomain[searchdomains] = NULL;
+ }
}
#endif
@@ -836,6 +873,7 @@ const char *resolve_name(const char *name, int mailbox)
}
#endif
+
#ifdef L_gethostbyname
struct hostent *gethostbyname(const char *name)
@@ -844,6 +882,7 @@ struct hostent *gethostbyname(const char *name)
static char namebuf[256];
static struct in_addr in;
static struct in_addr *addr_list[2];
+ struct hostent *hp;
unsigned char *packet;
struct resolv_answer a;
int i;
@@ -853,13 +892,16 @@ struct hostent *gethostbyname(const char *name)
if (!name)
return 0;
-
+
+ if ((hp = get_hosts_byname(name))) /* do /etc/hosts first */
+ return(hp);
+
memset(&h, 0, sizeof(h));
addr_list[0] = &in;
addr_list[1] = 0;
- strcpy(namebuf, name);
+ strncpy(namebuf, name, sizeof(namebuf));
/* First check if this is already an address */
if (inet_aton(name, &in)) {
@@ -909,6 +951,66 @@ struct hostent *gethostbyname(const char *name)
}
#endif
+
+#ifdef L_getnetbyname
+
+struct netent * getnetbyname(const char * name)
+{
+ return NULL;
+}
+#endif
+
+
+#ifdef L_res_init
+
+int res_init()
+{
+ return(0);
+}
+#endif
+
+
+#ifdef L_res_query
+
+#ifndef MIN
+#define MIN(x, y) ((x) < (y) ? (x) : (y))
+#endif
+
+int res_query(const char *dname, int class, int type,
+ unsigned char *answer, int anslen)
+{
+ unsigned char * packet = 0;
+ struct resolv_answer a;
+ int i;
+
+ open_nameservers();
+
+ if (!dname || class != 1 /* CLASS_IN */)
+ return(-1);
+
+ memset((char *) &a, '\0', sizeof(a));
+
+ i = dns_lookup(dname, type, nameservers, nameserver, &packet, &a);
+
+ if (i < 0)
+ return(-1);
+
+ free(a.dotted);
+
+ if (a.atype == type) { /* CNAME*/
+ if (anslen && answer)
+ memcpy(answer, a.rdata, MIN(anslen, a.rdlength));
+ if (packet)
+ free(packet);
+ return(MIN(anslen, a.rdlength));
+ }
+ if (packet)
+ free(packet);
+ return 0;
+}
+#endif
+
+
#ifdef L_gethostbyaddr
struct hostent *gethostbyaddr(const char *addr, int len, int type)
@@ -917,6 +1019,7 @@ struct hostent *gethostbyaddr(const char *addr, int len, int type)
static char namebuf[256];
static struct in_addr in;
static struct in_addr *addr_list[2];
+ struct hostent *hp;
unsigned char *packet;
struct resolv_answer a;
int i;
@@ -925,6 +1028,9 @@ struct hostent *gethostbyaddr(const char *addr, int len, int type)
if (!addr || (len != sizeof(in)) || (type != AF_INET))
return 0;
+ if ((hp = get_hosts_byaddr(addr, len, type))) /* do /etc/hosts first */
+ return(hp);
+
memcpy(&in.s_addr, addr, len);
open_nameservers();
@@ -978,3 +1084,96 @@ struct hostent *gethostbyaddr(const char *addr, int len, int type)
return &h;
}
#endif
+
+
+#ifdef L_read_etc_hosts
+
+struct hostent * read_etc_hosts(const char * name, int ip)
+{
+ static struct hostent h;
+ static struct in_addr in;
+ static struct in_addr *addr_list[2];
+ static char line[80];
+ FILE *fp;
+ char *cp;
+#define MAX_ALIAS 5
+ char *alias[MAX_ALIAS];
+ int aliases, i;
+
+ if ((fp = fopen("/etc/hosts", "r")) == NULL &&
+ (fp = fopen("/etc/config/hosts", "r")) == NULL)
+ return((struct hostent *) NULL);
+
+ while (fgets(line, sizeof(line), fp)) {
+ if ((cp = strchr(line, '#')))
+ *cp = '\0';
+ aliases = 0;
+
+ cp = line;
+ while (*cp) {
+ while (*cp && isspace(*cp))
+ *cp++ = '\0';
+ if (!*cp)
+ continue;
+ if (aliases < MAX_ALIAS)
+ alias[aliases++] = cp;
+ while (*cp && !isspace(*cp))
+ cp++;
+ }
+
+ if (aliases < 2)
+ continue; /* syntax error really */
+
+ if (ip) {
+ if (strcmp(name, alias[0]) != 0)
+ continue;
+ } else {
+ for (i = 1; i < aliases; i++)
+ if (strcasecmp(name, alias[i]) == 0)
+ break;
+ if (i >= aliases)
+ continue;
+ }
+
+ if (inet_aton(alias[0], &in) == 0)
+ break; /* bad ip address */
+
+ addr_list[0] = &in;
+ addr_list[1] = 0;
+ h.h_name = alias[1];
+ h.h_addrtype = AF_INET;
+ h.h_length = sizeof(in);
+ h.h_addr_list = (char**) addr_list;
+ fclose(fp);
+ return(&h);
+ }
+ fclose(fp);
+ return((struct hostent *) NULL);
+}
+#endif
+
+
+#ifdef L_get_hosts_byname
+
+struct hostent * get_hosts_byname(const char * name)
+{
+ return(read_etc_hosts(name, 0));
+}
+#endif
+
+
+#ifdef L_get_hosts_byaddr
+
+struct hostent * get_hosts_byaddr(const char * addr, int len, int type)
+{
+ char ipaddr[20];
+
+ if (type != AF_INET || len != sizeof(struct in_addr))
+ return((struct hostent *) NULL);
+
+ strcpy(ipaddr, inet_ntoa(* (struct in_addr *) addr));
+ return(read_etc_hosts(ipaddr, 1));
+}
+#endif
+
+
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