Rework wget, the xconnect interface, and its various clients

in order to fix the problems with round robin DNS reported
by Andrew Flegg:
    http://busybox.net/lists/busybox/2003-October/009579.html

This removes the ipv6 specific xconnect dns lookups.  I do
not see why that would need to be special cased for ipv6 as
was done, but that will just have to be tested.

So IPV6 people -- please test this change!

 -Erik

6 files changed, 70 insertions, 67 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 7587a407c..53062de4d 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -109,9 +109,9 @@ extern int is_directory(const char *name, int followLinks, struct stat *statBuf)
 extern int remove_file(const char *path, int flags);
 extern int copy_file(const char *source, const char *dest, int flags);
 extern ssize_t safe_read(int fd, void *buf, size_t count);
-extern ssize_t safe_write(int fd, void *buf, size_t count);
-extern ssize_t bb_full_write(int fd, const void *buf, size_t len);
 extern ssize_t bb_full_read(int fd, void *buf, size_t len);
+extern ssize_t safe_write(int fd, const void *buf, size_t count);
+extern ssize_t bb_full_write(int fd, const void *buf, size_t len);
 extern int recursive_action(const char *fileName, int recurse,
           int followLinks, int depthFirst,
           int (*fileAction) (const char *fileName, struct stat* statbuf, void* userData),
@@ -294,7 +294,9 @@ extern struct hostent *xgethostbyname(const char *name);
 extern struct hostent *xgethostbyname2(const char *name, int af);
 extern int create_icmp_socket(void);
 extern int create_icmp6_socket(void);
-extern int xconnect(const char *host, const char *port);
+extern int xconnect(struct sockaddr_in *s_addr);
+extern int bb_getport(char *port);
+extern void bb_lookup_host(struct sockaddr_in *s_in, char *host, char *port);
 
 //#warning wrap this?
 char *dirname (char *path);
diff --git a/libbb/safe_write.c b/libbb/safe_write.c
index dd35f35ae..0ac6c2d96 100644
--- a/libbb/safe_write.c
+++ b/libbb/safe_write.c
@@ -26,7 +26,7 @@
 
 
 
-ssize_t safe_write(int fd, void *buf, size_t count)
+ssize_t safe_write(int fd, const void *buf, size_t count)
 {
         ssize_t n;
 
diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index 2945d760f..27459791e 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -11,69 +11,57 @@
 #include <stdlib.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <errno.h>
 #include <netdb.h>
+#include <sys/socket.h>
 #include <netinet/in.h>
+#include <arpa/inet.h>
 #include "libbb.h"
 
-int xconnect(const char *host, const char *port)
+int bb_getport(char *port)
 {
-#ifdef CONFIG_FEATURE_IPV6
-        struct addrinfo hints;
-        struct addrinfo *res;
-        struct addrinfo *addr_info;
-        int error;
-        int s;
+        int port_nr;
+        char *endptr;
+        struct servent *tserv;
 
-        memset(&hints, 0, sizeof(hints));
-        /* set-up hints structure */
-        hints.ai_family = PF_UNSPEC;
-        hints.ai_socktype = SOCK_STREAM;
-        error = getaddrinfo(host, port, &hints, &res);
-        if (error||!res)
-                bb_perror_msg_and_die(gai_strerror(error));
-        addr_info=res;
-        while (res) {
-                s=socket(res->ai_family, res->ai_socktype, res->ai_protocol);
-                if (s<0)
-                {
-                        error=s;
-                        res=res->ai_next;
-                        continue;
-                }
-                /* try to connect() to res->ai_addr */
-                error = connect(s, res->ai_addr, res->ai_addrlen);
-                if (error >= 0)
-                        break;
-                close(s);
-                res=res->ai_next;
+        if (!port) {
+                return -1;
         }
-        freeaddrinfo(addr_info);
-        if (error < 0)
+        port_nr=strtol(port, &endptr, 10);
+        if (errno != 0 || *endptr!='\0' || endptr==port || port_nr < 1 || port_nr > 65536) 
         {
-                bb_perror_msg_and_die("Unable to connect to remote host (%s)", host);
+                if (port_nr==0 && (tserv = getservbyname(port, "tcp")) != NULL) {
+                        port_nr = tserv->s_port;
+                } else {
+                        return -1;
+                }
+        } else {
+                port_nr = htons(port_nr);
         }
-        return s;
-#else
-        struct sockaddr_in s_addr;
-        int s = socket(AF_INET, SOCK_STREAM, 0);
-        struct servent *tserv;
-        int port_nr=htons(atoi(port));
-        struct hostent * he;
-
-        if (port_nr==0 && (tserv = getservbyname(port, "tcp")) != NULL)
-                port_nr = tserv->s_port;
+        return port_nr;
+}
 
-        memset(&s_addr, 0, sizeof(struct sockaddr_in));
-        s_addr.sin_family = AF_INET;
-        s_addr.sin_port = port_nr;
+void bb_lookup_host(struct sockaddr_in *s_in, char *host, char *port)
+{
+        struct hostent *he;
 
+        memset(s_in, 0, sizeof(struct sockaddr_in));
+        s_in->sin_family = AF_INET;
         he = xgethostbyname(host);
-        memcpy(&s_addr.sin_addr, he->h_addr, sizeof s_addr.sin_addr);
+        memcpy(&(s_in->sin_addr), he->h_addr_list[0], he->h_length);
 
-        if (connect(s, (struct sockaddr *)&s_addr, sizeof s_addr) < 0)
+        if (port) {
+                s_in->sin_port=bb_getport(port);
+        }
+}
+
+int xconnect(struct sockaddr_in *s_addr)
+{
+        int s = socket(AF_INET, SOCK_STREAM, 0);
+        if (connect(s, (struct sockaddr_in *)s_addr, sizeof(struct sockaddr_in)) < 0)
         {
-                bb_perror_msg_and_die("Unable to connect to remote host (%s)", host);
+                bb_perror_msg_and_die("Unable to connect to remote host (%s)", 
+                                inet_ntoa(s_addr->sin_addr));
         }
         return s;
-#endif
 }
diff --git a/networking/telnet.c b/networking/telnet.c
index ac6ec98de..92ddfaebf 100644
--- a/networking/telnet.c
+++ b/networking/telnet.c
@@ -573,6 +573,7 @@ extern int telnet_main(int argc, char** argv)
         char *host;
         char *port;
         int len;
+        struct sockaddr_in s_in;
 #ifdef USE_POLL
         struct pollfd ufds[2];
 #else   
@@ -601,7 +602,8 @@ extern int telnet_main(int argc, char** argv)
         
         host = argv[1];
         
-        G.netfd = xconnect(host, port);
+        bb_lookup_host(&s_in, host, port);
+        G.netfd = xconnect(&s_in);
 
         setsockopt(G.netfd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof one);
 
diff --git a/networking/wget.c b/networking/wget.c
index 597d61097..08026915e 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -40,7 +40,7 @@ struct host_info {
 };
 
 static void parse_url(char *url, struct host_info *h);
-static FILE *open_socket(char *host, int port);
+static FILE *open_socket(struct sockaddr_in *s_in, int port);
 static char *gethdr(char *buf, size_t bufsiz, FILE *fp, int *istrunc);
 static int ftpcmd(char *s1, char *s2, FILE *fp, char *buf);
 
@@ -155,6 +155,7 @@ int wget_main(int argc, char **argv)
         int extra_headers_left = sizeof(extra_headers);
         int which_long_opt = 0, option_index = -1;
         struct host_info server, target;
+        struct sockaddr_in s_in;
 
         FILE *sfp = NULL;                       /* socket to web/ftp server                     */
         FILE *dfp = NULL;                       /* socket to ftp server (data)          */
@@ -290,6 +291,15 @@ int wget_main(int argc, char **argv)
                         do_continue = 0;
         }
 
+        /* We want to do exactly _one_ DNS lookup, since some
+         * sites (i.e. ftp.us.debian.org) use round-robin DNS
+         * and we want to connect to only one IP... */
+        bb_lookup_host(&s_in, server.host, NULL);
+        if (quiet_flag==FALSE) {
+                fprintf(stdout, "Connecting to %s[%s]:%d\n",
+                                server.host, inet_ntoa(s_in.sin_addr), server.port);
+        }
+
         if (proxy || !target.is_ftp) {
                 /*
                  *  HTTP session
@@ -304,7 +314,7 @@ int wget_main(int argc, char **argv)
                          * Open socket to http server
                          */
                         if (sfp) fclose(sfp);
-                        sfp = open_socket(server.host, server.port);
+                        sfp = open_socket(&s_in, server.port);
                         
                         /*
                          * Send HTTP request.
@@ -416,7 +426,7 @@ read_response:
                 if (! target.user)
                         target.user = bb_xstrdup("anonymous:busybox@");
 
-                sfp = open_socket(server.host, server.port);
+                sfp = open_socket(&s_in, server.port);
                 if (ftpcmd(NULL, NULL, sfp, buf) != 220)
                         close_delete_and_die("%s", buf+4);
 
@@ -459,7 +469,7 @@ read_response:
                 port = atoi(s+1);
                 s = strrchr(buf, ',');
                 port += atoi(s+1) * 256;
-                dfp = open_socket(server.host, port);
+                dfp = open_socket(&s_in, port);
 
                 if (do_continue) {
                         sprintf(buf, "REST %ld", beg_range);
@@ -584,14 +594,16 @@ void parse_url(char *url, struct host_info *h)
 }
 
 
-FILE *open_socket(char *host, int port)
+FILE *open_socket(struct sockaddr_in *s_in, int port)
 {
         int fd;
         FILE *fp;
-        char port_str[10];
 
-        snprintf(port_str, sizeof(port_str), "%d", port);
-        fd=xconnect(host, port_str);
+        if (port>0 && port < 65536) {
+                s_in->sin_port=htons(port);
+        }
+
+        fd=xconnect(s_in);
 
         /*
          * Get the server onto a stdio stream.
@@ -838,7 +850,7 @@ progressmeter(int flag)
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *      $Id: wget.c,v 1.60 2003/09/15 08:33:37 andersen Exp $
+ *      $Id: wget.c,v 1.61 2003/10/31 09:31:43 andersen Exp $
  */
 
 
diff --git a/util-linux/rdate.c b/util-linux/rdate.c
index 8d156cc78..a822f42ff 100644
--- a/util-linux/rdate.c
+++ b/util-linux/rdate.c
@@ -47,17 +47,16 @@ static void socket_timeout(int sig)
 static time_t askremotedate(const char *host)
 {
         unsigned long int nett, localt;
-        const char *port="37";
+        struct sockaddr_in addr s_in;
         int fd;
 
-        if (getservbyname("time", "tcp") != NULL)
-                port="time";
+        bb_lookup_host(&s_in, host, "time");
 
         /* Add a timeout for dead or non accessable servers */
         alarm(10);
         signal(SIGALRM, socket_timeout);
 
-        fd = xconnect(host, port);
+        fd = xconnect(s_in);
 
         if (safe_read(fd, (void *)&nett, 4) != 4)    /* read time from server */
                 bb_error_msg_and_die("%s did not send the complete time", host);