1 files changed, 440 insertions, 0 deletions
diff --git a/lib/krb4.c b/lib/krb4.c
new file mode 100644
index 000000000..58354b602
--- /dev/null
+++ b/lib/krb4.c
@@ -0,0 +1,440 @@
+/* This source code was modified by Martin Hedenfalk <mhe@stacken.kth.se> for
+ * use in Curl. Martin's latest changes were done 2000-09-18.
+ *
+ * It has since been patched away like a madman by Daniel Stenberg to make it
+ * better applied to curl conditions, and to make it not use globals, pollute
+ * name space and more.
+ *
+ * Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska H�gskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * Copyright (c) 2004 - 2011 Daniel Stenberg
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the Institute 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 THE INSTITUTE 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 INSTITUTE 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.
+ *
+ */
+
+#include "setup.h"
+
+#ifndef CURL_DISABLE_FTP
+#ifdef HAVE_KRB4
+
+#ifdef HAVE_NETDB_H
+#include <netdb.h>
+#endif
+#include <krb.h>
+#include <des.h>
+
+#include "urldata.h"
+#include "curl_base64.h"
+#include "ftp.h"
+#include "sendf.h"
+#include "krb4.h"
+#include "inet_ntop.h"
+#include "curl_memory.h"
+
+/* The last #include file should be: */
+#include "memdebug.h"
+
+#define LOCAL_ADDR (&conn->local_addr)
+#define REMOTE_ADDR conn->ip_addr->ai_addr
+#define myctladdr LOCAL_ADDR
+#define hisctladdr REMOTE_ADDR
+
+struct krb4_data {
+  des_cblock key;
+  des_key_schedule schedule;
+  char name[ANAME_SZ];
+  char instance[INST_SZ];
+  char realm[REALM_SZ];
+};
+
+#ifndef HAVE_STRLCPY
+/* if it ever goes non-static, make it Curl_ prefixed! */
+static size_t
+strlcpy (char *dst, const char *src, size_t dst_sz)
+{
+  size_t n;
+  char *p;
+
+  for(p = dst, n = 0;
+      n + 1 < dst_sz && *src != '\0';
+      ++p, ++src, ++n)
+    *p = *src;
+  *p = '\0';
+  if(*src == '\0')
+    return n;
+  else
+    return n + strlen (src);
+}
+#else
+size_t strlcpy (char *dst, const char *src, size_t dst_sz);
+#endif
+
+static int
+krb4_check_prot(void *app_data, int level)
+{
+  app_data = NULL; /* prevent compiler warning */
+  if(level == PROT_CONFIDENTIAL)
+    return -1;
+  return 0;
+}
+
+static int
+krb4_decode(void *app_data, void *buf, int len, int level,
+            struct connectdata *conn)
+{
+  MSG_DAT m;
+  int e;
+  struct krb4_data *d = app_data;
+
+  if(level == PROT_SAFE)
+    e = krb_rd_safe(buf, len, &d->key,
+                    (struct sockaddr_in *)REMOTE_ADDR,
+                    (struct sockaddr_in *)LOCAL_ADDR, &m);
+  else
+    e = krb_rd_priv(buf, len, d->schedule, &d->key,
+                    (struct sockaddr_in *)REMOTE_ADDR,
+                    (struct sockaddr_in *)LOCAL_ADDR, &m);
+  if(e) {
+    struct SessionHandle *data = conn->data;
+    infof(data, "krb4_decode: %s\n", krb_get_err_text(e));
+    return -1;
+  }
+  memmove(buf, m.app_data, m.app_length);
+  return m.app_length;
+}
+
+static int
+krb4_overhead(void *app_data, int level, int len)
+{
+  /* no arguments are used, just init them to prevent compiler warnings */
+  app_data = NULL;
+  level = 0;
+  len = 0;
+  return 31;
+}
+
+static int
+krb4_encode(void *app_data, const void *from, int length, int level, void **to,
+            struct connectdata *conn)
+{
+  struct krb4_data *d = app_data;
+  *to = malloc(length + 31);
+  if(!*to)
+    return -1;
+  if(level == PROT_SAFE)
+    /* NOTE that the void* cast is safe, krb_mk_safe/priv don't modify the
+     * input buffer
+     */
+    return krb_mk_safe((void*)from, *to, length, &d->key,
+                       (struct sockaddr_in *)LOCAL_ADDR,
+                       (struct sockaddr_in *)REMOTE_ADDR);
+  else if(level == PROT_PRIVATE)
+    return krb_mk_priv((void*)from, *to, length, d->schedule, &d->key,
+                       (struct sockaddr_in *)LOCAL_ADDR,
+                       (struct sockaddr_in *)REMOTE_ADDR);
+  else
+    return -1;
+}
+
+static int
+mk_auth(struct krb4_data *d, KTEXT adat,
+        const char *service, char *host, int checksum)
+{
+  int ret;
+  CREDENTIALS cred;
+  char sname[SNAME_SZ], inst[INST_SZ], realm[REALM_SZ];
+
+  strlcpy(sname, service, sizeof(sname));
+  strlcpy(inst, krb_get_phost(host), sizeof(inst));
+  strlcpy(realm, krb_realmofhost(host), sizeof(realm));
+  ret = krb_mk_req(adat, sname, inst, realm, checksum);
+  if(ret)
+    return ret;
+  strlcpy(sname, service, sizeof(sname));
+  strlcpy(inst, krb_get_phost(host), sizeof(inst));
+  strlcpy(realm, krb_realmofhost(host), sizeof(realm));
+  ret = krb_get_cred(sname, inst, realm, &cred);
+  memmove(&d->key, &cred.session, sizeof(des_cblock));
+  des_key_sched(&d->key, d->schedule);
+  memset(&cred, 0, sizeof(cred));
+  return ret;
+}
+
+#ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM
+int krb_get_our_ip_for_realm(char *, struct in_addr *);
+#endif
+
+static int
+krb4_auth(void *app_data, struct connectdata *conn)
+{
+  int ret;
+  char *p;
+  unsigned char *ptr;
+  size_t len = 0;
+  KTEXT_ST adat;
+  MSG_DAT msg_data;
+  int checksum;
+  u_int32_t cs;
+  struct krb4_data *d = app_data;
+  char *host = conn->host.name;
+  ssize_t nread;
+  int l = sizeof(conn->local_addr);
+  struct SessionHandle *data = conn->data;
+  CURLcode result;
+  size_t base64_sz = 0;
+
+  if(getsockname(conn->sock[FIRSTSOCKET],
+                 (struct sockaddr *)LOCAL_ADDR, &l) < 0)
+    perror("getsockname()");
+
+  checksum = getpid();
+  ret = mk_auth(d, &adat, "ftp", host, checksum);
+  if(ret == KDC_PR_UNKNOWN)
+    ret = mk_auth(d, &adat, "rcmd", host, checksum);
+  if(ret) {
+    infof(data, "%s\n", krb_get_err_text(ret));
+    return AUTH_CONTINUE;
+  }
+
+#ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM
+  if(krb_get_config_bool("nat_in_use")) {
+    struct sockaddr_in *localaddr  = (struct sockaddr_in *)LOCAL_ADDR;
+    struct in_addr natAddr;
+
+    if(krb_get_our_ip_for_realm(krb_realmofhost(host),
+                                 &natAddr) != KSUCCESS
+        && krb_get_our_ip_for_realm(NULL, &natAddr) != KSUCCESS)
+      infof(data, "Can't get address for realm %s\n",
+                 krb_realmofhost(host));
+    else {
+      if(natAddr.s_addr != localaddr->sin_addr.s_addr) {
+        char addr_buf[128];
+        if(Curl_inet_ntop(AF_INET, natAddr, addr_buf, sizeof(addr_buf)))
+          infof(data, "Using NAT IP address (%s) for kerberos 4\n", addr_buf);
+        localaddr->sin_addr = natAddr;
+      }
+    }
+  }
+#endif
+
+  result = Curl_base64_encode(conn->data, (char *)adat.dat, adat.length,
+                              &p, &base64_sz);
+  if(result) {
+    Curl_failf(data, "base64-encoding: %s", curl_easy_strerror(result));
+    return AUTH_CONTINUE;
+  }
+
+  result = Curl_ftpsendf(conn, "ADAT %s", p);
+
+  free(p);
+
+  if(result)
+    return -2;
+
+  if(Curl_GetFTPResponse(&nread, conn, NULL))
+    return -1;
+
+  if(data->state.buffer[0] != '2') {
+    Curl_failf(data, "Server didn't accept auth data");
+    return AUTH_ERROR;
+  }
+
+  p = strstr(data->state.buffer, "ADAT=");
+  if(!p) {
+    Curl_failf(data, "Remote host didn't send adat reply");
+    return AUTH_ERROR;
+  }
+  p += 5;
+  result = Curl_base64_decode(p, &ptr, &len);
+  if(result) {
+    Curl_failf(data, "base64-decoding: %s", curl_easy_strerror(result));
+    return AUTH_ERROR;
+  }
+  if(len > sizeof(adat.dat)-1) {
+    free(ptr);
+    ptr = NULL;
+    len = 0;
+  }
+  if(!len || !ptr) {
+    Curl_failf(data, "Failed to decode base64 from server");
+    return AUTH_ERROR;
+  }
+  memcpy((char *)adat.dat, ptr, len);
+  free(ptr);
+  adat.length = len;
+  ret = krb_rd_safe(adat.dat, adat.length, &d->key,
+                    (struct sockaddr_in *)hisctladdr,
+                    (struct sockaddr_in *)myctladdr, &msg_data);
+  if(ret) {
+    Curl_failf(data, "Error reading reply from server: %s",
+               krb_get_err_text(ret));
+    return AUTH_ERROR;
+  }
+  krb_get_int(msg_data.app_data, &cs, 4, 0);
+  if(cs - checksum != 1) {
+    Curl_failf(data, "Bad checksum returned from server");
+    return AUTH_ERROR;
+  }
+  return AUTH_OK;
+}
+
+struct Curl_sec_client_mech Curl_krb4_client_mech = {
+    "KERBEROS_V4",
+    sizeof(struct krb4_data),
+    NULL, /* init */
+    krb4_auth,
+    NULL, /* end */
+    krb4_check_prot,
+    krb4_overhead,
+    krb4_encode,
+    krb4_decode
+};
+
+static enum protection_level
+krb4_set_command_prot(struct connectdata *conn, enum protection_level level)
+{
+  enum protection_level old = conn->command_prot;
+  DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
+  conn->command_prot = level;
+  return old;
+}
+
+CURLcode Curl_krb_kauth(struct connectdata *conn)
+{
+  des_cblock key;
+  des_key_schedule schedule;
+  KTEXT_ST tkt, tktcopy;
+  char *name;
+  char *p;
+  char passwd[100];
+  size_t tmp = 0;
+  ssize_t nread;
+  enum protection_level save;
+  CURLcode result;
+  unsigned char *ptr;
+  size_t base64_sz = 0;
+
+  save = krb4_set_command_prot(conn, PROT_PRIVATE);
+
+  result = Curl_ftpsendf(conn, "SITE KAUTH %s", conn->user);
+
+  if(result)
+    return result;
+
+  result = Curl_GetFTPResponse(&nread, conn, NULL);
+  if(result)
+    return result;
+
+  if(conn->data->state.buffer[0] != '3') {
+    krb4_set_command_prot(conn, save);
+    return CURLE_FTP_WEIRD_SERVER_REPLY;
+  }
+
+  p = strstr(conn->data->state.buffer, "T=");
+  if(!p) {
+    Curl_failf(conn->data, "Bad reply from server");
+    krb4_set_command_prot(conn, save);
+    return CURLE_FTP_WEIRD_SERVER_REPLY;
+  }
+
+  p += 2;
+  result = Curl_base64_decode(p, &ptr, &tmp);
+  if(result) {
+    Curl_failf(conn->data, "base64-decoding: %s", curl_easy_strerror(result));
+    return result;
+  }
+  if(tmp >= sizeof(tkt.dat)) {
+    free(ptr);
+    ptr = NULL;
+    tmp = 0;
+  }
+  if(!tmp || !ptr) {
+    Curl_failf(conn->data, "Failed to decode base64 in reply");
+    krb4_set_command_prot(conn, save);
+    return CURLE_FTP_WEIRD_SERVER_REPLY;
+  }
+  memcpy((char *)tkt.dat, ptr, tmp);
+  free(ptr);
+  tkt.length = tmp;
+  tktcopy.length = tkt.length;
+
+  p = strstr(conn->data->state.buffer, "P=");
+  if(!p) {
+    Curl_failf(conn->data, "Bad reply from server");
+    krb4_set_command_prot(conn, save);
+    return CURLE_FTP_WEIRD_SERVER_REPLY;
+  }
+  name = p + 2;
+  for(; *p && *p != ' ' && *p != '\r' && *p != '\n'; p++);
+  *p = 0;
+
+  des_string_to_key (conn->passwd, &key);
+  des_key_sched(&key, schedule);
+
+  des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat,
+                   tkt.length,
+                   schedule, &key, DES_DECRYPT);
+  if(strcmp ((char*)tktcopy.dat + 8,
+              KRB_TICKET_GRANTING_TICKET) != 0) {
+    afs_string_to_key(passwd,
+                      krb_realmofhost(conn->host.name),
+                      &key);
+    des_key_sched(&key, schedule);
+    des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat,
+                     tkt.length,
+                     schedule, &key, DES_DECRYPT);
+  }
+  memset(key, 0, sizeof(key));
+  memset(schedule, 0, sizeof(schedule));
+  memset(passwd, 0, sizeof(passwd));
+  result = Curl_base64_encode(conn->data, (char *)tktcopy.dat, tktcopy.length,
+                              &p, &base64_sz);
+  if(result) {
+    Curl_failf(conn->data, "base64-encoding: %s", curl_easy_strerror(result));
+    krb4_set_command_prot(conn, save);
+    return result;
+  }
+  memset (tktcopy.dat, 0, tktcopy.length);
+
+  result = Curl_ftpsendf(conn, "SITE KAUTH %s %s", name, p);
+  free(p);
+  if(result)
+    return result;
+
+  result = Curl_GetFTPResponse(&nread, conn, NULL);
+  if(result)
+    return result;
+  krb4_set_command_prot(conn, save);
+
+  return CURLE_OK;
+}
+
+#endif /* HAVE_KRB4 */
+#endif /* CURL_DISABLE_FTP */