Merge from EXISCAN branch.

[exim.git] / src / src / srs.c

diff --git a/src/src/srs.c b/src/src/srs.c
new file mode 100644 (file)
index 0000000..a1e08c3
--- /dev/null
+++ b/src/src/srs.c
@@ -0,0 +1,206 @@
+/* $Cambridge: exim/src/src/srs.c,v 1.2 2004/12/16 15:11:47 tom Exp $ */
+
+/*************************************************
+*     Exim - an Internet mail transport agent    *
+*************************************************/
+
+/* SRS - Sender rewriting scheme support
+  ©2004 Miles Wilton <miles@mirtol.com>
+  License: GPL */
+
+#include "exim.h"
+#ifdef EXPERIMENTAL_SRS
+
+#include <srs_alt.h>
+#include "srs.h"
+
+srs_t    *srs                   = NULL;
+uschar   *srs_db_forward        = NULL;
+uschar   *srs_db_reverse        = NULL;
+
+
+/* srs_init just initialises libsrs and creates (if necessary)
+   an srs object to use for all srs calls in this instance */
+   
+int eximsrs_init()
+{
+  int co;
+  uschar *list = srs_config;
+  char secret_buf[SRS_MAX_SECRET_LENGTH];
+  char *secret;
+  char sbuf[4];
+  char *sbufp;
+  int hashlen, maxage;
+
+  
+  if(!srs)
+  {
+    // Check config
+    if(!srs_config)
+    {
+      log_write(0, LOG_MAIN | LOG_PANIC,
+          "SRS Configuration Error");
+      return DEFER;
+    }
+    
+    // Get config
+    co = 0;
+    if((secret = string_nextinlist(&list, &co, secret_buf,
+                                   SRS_MAX_SECRET_LENGTH)) == NULL)
+    {
+      log_write(0, LOG_MAIN | LOG_PANIC,
+          "SRS Configuration Error: No secret specified");
+      return DEFER;
+    }
+    
+    if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) == NULL)
+      maxage = 31;
+    else
+      maxage = atoi(sbuf);
+    if(maxage < 0 || maxage > 365)
+    {
+      log_write(0, LOG_MAIN | LOG_PANIC,
+          "SRS Configuration Error: Invalid maximum timestamp age");
+      return DEFER;
+    }
+
+    if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) == NULL)
+      hashlen = 6;
+    else
+      hashlen = atoi(sbuf);
+    if(hashlen < 1 || hashlen > 20)
+    {
+      log_write(0, LOG_MAIN | LOG_PANIC,
+          "SRS Configuration Error: Invalid hash length");
+      return DEFER;
+    }
+    
+    
+    if((srs = srs_open(secret, strnlen(secret, SRS_MAX_SECRET_LENGTH),
+                      maxage, hashlen, hashlen)) == NULL)
+    {
+      log_write(0, LOG_MAIN | LOG_PANIC,
+          "Failed to allocate SRS memory");
+      return DEFER;
+    }
+
+
+    if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL)
+      srs_set_option(srs, SRS_OPTION_USETIMESTAMP, atoi(sbuf));
+    
+    if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL)
+      srs_set_option(srs, SRS_OPTION_USEHASH, atoi(sbuf));
+
+    DEBUG(D_any)
+      debug_printf("SRS initialized\n");
+  }
+
+  return OK;
+}
+
+
+int eximsrs_done()
+{
+  if(srs)
+    srs_close(srs);
+  
+  srs = NULL;
+
+  return OK;
+}
+
+
+int eximsrs_forward(uschar **result, uschar *orig_sender, uschar *domain)
+{
+  char res[512];
+  int n;
+
+  if((n = srs_forward(srs, orig_sender, domain, res, sizeof(res))) & SRS_RESULT_FAIL)
+  {
+    DEBUG(D_any)
+      debug_printf("srs_forward failed (%s, %s): %s\n", orig_sender, domain, srs_geterrormsg(n));
+    return DEFER;
+  }
+
+  *result = string_copy(res);
+  return OK;
+}
+
+
+int eximsrs_reverse(uschar **result, uschar *address)
+{
+  char res[512];
+  int n;
+
+  if((n = srs_reverse(srs, address, res, sizeof(res))) & SRS_RESULT_FAIL)
+  {
+    DEBUG(D_any)
+      debug_printf("srs_reverse failed (%s): %s\n", address, srs_geterrormsg(n));
+    if(n == SRS_RESULT_NOTSRS || n == SRS_RESULT_BADSRS)
+      return DECLINE;
+    if(n == SRS_RESULT_BADHASH || n == SRS_RESULT_BADTIMESTAMP || n == SRS_RESULT_TIMESTAMPEXPIRED)
+      return FAIL;
+    return DEFER;
+  }
+
+  *result = string_copy(res);
+  return OK;
+}
+
+
+int eximsrs_db_set(BOOL reverse, uschar *srs_db)
+{
+  if(reverse)
+    srs_db_reverse = string_copy(srs_db);
+  else
+    srs_db_forward = string_copy(srs_db);
+    
+  if(srs_set_db_functions(srs, eximsrs_db_insert, eximsrs_db_lookup) * SRS_RESULT_FAIL)
+    return DEFER;
+  
+  return OK;
+}
+
+
+srs_result eximsrs_db_insert(srs_t *srs, char *data, uint data_len, char *result, uint result_len)
+{
+  uschar *res;
+  char buf[64];
+
+  srs_db_address = string_copyn(data, data_len);
+  if(srs_generate_unique_id(srs, srs_db_address, buf, 64) & SRS_RESULT_FAIL)
+    return DEFER;
+  
+  srs_db_key = string_copyn(buf, 16);
+  
+  if((res = expand_string(srs_db_forward)) == NULL)
+    return SRS_RESULT_DBERROR;
+  
+  if(result_len < 17)
+    return SRS_RESULT_DBERROR;
+    
+  strncpy(result, srs_db_key, result_len);
+
+  return SRS_RESULT_OK;
+}
+
+
+srs_result eximsrs_db_lookup(srs_t *srs, char *data, uint data_len, char *result, uint result_len)
+{
+  uschar *res;
+
+  srs_db_key = string_copyn(data, data_len);
+  if((res = expand_string(srs_db_reverse)) == NULL)
+    return SRS_RESULT_DBERROR;
+  
+  if(Ustrlen(res) >= result_len)
+    return SRS_RESULT_ADDRESSTOOLONG;
+    
+  strncpy(result, res, result_len);
+
+  return SRS_RESULT_OK;
+}
+
+
+#endif
+