X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/0756eb3cb50d73a77b486e47528f7cb1bffdb299..4730f9424e0addeb902cc842508eea3f47a131ca:/src/src/auths/plaintext.c

diff --git a/src/src/auths/plaintext.c b/src/src/auths/plaintext.c
index b15a08d51..2aea4a492 100644
--- a/src/src/auths/plaintext.c
+++ b/src/src/auths/plaintext.c
@@ -1,10 +1,10 @@
-/* $Cambridge: exim/src/src/auths/plaintext.c,v 1.1 2004/10/07 13:10:01 ph10 Exp $ */
+/* $Cambridge: exim/src/src/auths/plaintext.c,v 1.5 2006/02/23 12:41:22 ph10 Exp $ */
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2004 */
+/* Copyright (c) University of Cambridge 1995 - 2006 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 #include "../exim.h"
@@ -14,6 +14,8 @@
 /* Options specific to the plaintext authentication mechanism. */
 
 optionlist auth_plaintext_options[] = {
+  { "client_ignore_invalid_base64", opt_bool,
+      (void *)(offsetof(auth_plaintext_options_block, client_ignore_invalid_base64)) },
   { "client_send",        opt_stringptr,
       (void *)(offsetof(auth_plaintext_options_block, client_send)) },
   { "server_condition",   opt_stringptr,
@@ -33,7 +35,8 @@ int auth_plaintext_options_count =
 auth_plaintext_options_block auth_plaintext_option_defaults = {
   NULL,              /* server_condition */
   NULL,              /* server_prompts */
-  NULL               /* client_send */
+  NULL,              /* client_send */
+  FALSE              /* client_ignore_invalid_base64 */
 };
 
 
@@ -87,14 +90,16 @@ if (prompts != NULL)
   }
 
 /* If data was supplied on the AUTH command, decode it, and split it up into
-multiple items at binary zeros. If the data consists of the string "=" it
-indicates a single, empty string. */
+multiple items at binary zeros. The strings are put into $auth1, $auth2, etc,
+up to a maximum. To retain backwards compatibility, they are also put int $1,
+$2, etc. If the data consists of the string "=" it indicates a single, empty
+string. */
 
 if (*data != 0)
   {
   if (Ustrcmp(data, "=") == 0)
     {
-    expand_nstring[++expand_nmax] = US"";
+    auth_vars[0] = expand_nstring[++expand_nmax] = US"";
     expand_nlength[expand_nmax] = 0;
     }
   else
@@ -103,6 +108,7 @@ if (*data != 0)
     end = clear + len;
     while (clear < end && expand_nmax < EXPAND_MAXN)
       {
+      if (expand_nmax < AUTH_VARS) auth_vars[expand_nmax] = clear;
       expand_nstring[++expand_nmax] = clear;
       while (*clear != 0) clear++;
       expand_nlength[expand_nmax] = clear++ - expand_nstring[expand_nmax];
@@ -126,6 +132,7 @@ while ((s = string_nextinlist(&prompts, &sep, big_buffer, big_buffer_size))
   /* This loop must run at least once, in case the length is zero */
   do
     {
+    if (expand_nmax < AUTH_VARS) auth_vars[expand_nmax] = clear;
     expand_nstring[++expand_nmax] = clear;
     while (*clear != 0) clear++;
     expand_nlength[expand_nmax] = clear++ - expand_nstring[expand_nmax];
@@ -133,9 +140,9 @@ while ((s = string_nextinlist(&prompts, &sep, big_buffer, big_buffer_size))
   while (clear < end && expand_nmax < EXPAND_MAXN);
   }
 
-/* We now have a number of items of data in $1, $2, etc. Match against the
-decoded data by expanding the condition. Also expand the id to set if
-authentication succeeds. */
+/* We now have a number of items of data in $auth1, $auth2, etc (and also, for
+compatibility, in $1, $2, etc). Match against the decoded data by expanding the
+condition. */
 
 cond = expand_string(ob->server_condition);
 
@@ -143,6 +150,11 @@ HDEBUG(D_auth)
   {
   int i;
   debug_printf("%s authenticator:\n", ablock->name);
+  for (i = 0; i < AUTH_VARS; i++)
+    {
+    if (auth_vars[i] != NULL)
+      debug_printf("  $auth%d = %s\n", i + 1, auth_vars[i]);
+    }
   for (i = 1; i <= expand_nmax; i++)
     debug_printf("  $%d = %.*s\n", i, expand_nlength[i], expand_nstring[i]);
   debug_print_string(ablock->server_debug_string);    /* customized debug */
@@ -207,6 +219,7 @@ uschar *text = ob->client_send;
 uschar *s;
 BOOL first = TRUE;
 int sep = 0;
+int auth_var_idx = 0;
 
 /* The text is broken up into a number of different data items, which are
 sent one by one. The first one is sent with the AUTH command; the remainder are
@@ -214,8 +227,9 @@ sent in response to subsequent prompts. Each is expanded before being sent. */
 
 while ((s = string_nextinlist(&text, &sep, big_buffer, big_buffer_size)) != NULL)
   {
-  int i, len;
+  int i, len, clear_len;
   uschar *ss = expand_string(s);
+  uschar *clear;
 
   /* Forced expansion failure is not an error; authentication is abandoned. On
   all but the first string, we have to abandon the authentication attempt by
@@ -230,7 +244,11 @@ while ((s = string_nextinlist(&text, &sep, big_buffer, big_buffer_size)) != NULL
       if (smtp_write_command(outblock, FALSE, "*\r\n") >= 0)
         (void) smtp_read_response(inblock, US buffer, buffsize, '2', timeout);
       }
-    if (expand_string_forcedfail) return CANCELLED;
+    if (expand_string_forcedfail)
+      {
+      *buffer = 0;       /* No message */
+      return CANCELLED;
+      }
     string_format(buffer, buffsize, "expansion of \"%s\" failed in %s "
       "authenticator: %s", ssave, ablock->name, expand_string_message);
     return ERROR;
@@ -295,6 +313,34 @@ while ((s = string_nextinlist(&text, &sep, big_buffer, big_buffer_size)) != NULL
       "authenticator", ablock->name);
     return ERROR;
     }
+
+  /* Now that we know we'll continue, we put the received data into $auth<n>,
+  if possible. First, decode it: buffer+4 skips over the SMTP status code. */
+
+  clear_len = auth_b64decode(buffer+4, &clear);
+
+  /* If decoding failed, the default is to terminate the authentication, and
+  return FAIL, with the SMTP response still in the buffer. However, if client_
+  ignore_invalid_base64 is set, we ignore the error, and put an empty string
+  into $auth<n>. */
+
+  if (clear_len < 0)
+    {
+    uschar *save_bad = string_copy(buffer);
+    if (!ob->client_ignore_invalid_base64)
+      {
+      if (smtp_write_command(outblock, FALSE, "*\r\n") >= 0)
+        (void)smtp_read_response(inblock, US buffer, buffsize, '2', timeout);
+      string_format(buffer, buffsize, "Invalid base64 string in server "
+        "response \"%s\"", save_bad);
+      return CANCELLED;
+      }
+    clear = US"";
+    clear_len = 0;
+    }
+
+  if (auth_var_idx < AUTH_VARS)
+    auth_vars[auth_var_idx++] = string_copy(clear);
   }
 
 /* Control should never actually get here. */