Removed debugging statements.

src/debug_helpers.c

@@ -0,0 +1,26 @@
+/*
+ * Convert a string to its hexadecimal representation.
+ *
+ * Use like this:
+ * log_write(0, LOG_MAIN, "DEBUG: %s", string2hex(var, var_len));
+*/
+char * string2hex(unsigned char * input, size_t length) {
+    const int growth = 3;
+    char * outstring = store_get(growth*length+1);
+    memset(outstring, 0, 3*length+1);
+    for (int i =0; i<length; i++) {
+        sprintf(outstring+i*growth, "%02x ", input[i]);
+    }
+    return outstring;
+}
+
+/*
+ * How to debug this library:
+ *
+ * 1. Add this code to the first “breakpoint”:
+ *    log_write(0, LOG_MAIN, "pid: %d", getpid()); int busywait = 0; while (busywait == 0) {}
+ * 2. Compile.
+ * 3. Run “exim -be […]” to call the lib; see simple_exim_test.sh for details.
+ * 4. Read exim pid from log output. Attach to the looping exim process with “gdb -p PID”
+ * 5. Prepare breakpoints, watches, etc. Set busywait to 1 and continue.
+ */

src/debug_helpers.h

@@ -0,0 +1,8 @@
+//
+// Created by sprawl on 20/08/2021.
+//
+
+#ifndef EXIM_ENCRYPT_DLFUNC_DEBUG_HELPERS_H
+#define EXIM_ENCRYPT_DLFUNC_DEBUG_HELPERS_H
+
+#endif //EXIM_ENCRYPT_DLFUNC_DEBUG_HELPERS_H

src/libexim-encrypt-dlfunc.c

@@ -9,16 +9,6 @@
 /* Exim4 dlfunc API header */
 #include <local_scan.h>
 
-char * string2hex(unsigned char * input, size_t length) {
-    const int growth = 3;
-    char * outstring = store_get(growth*length+1);
-    memset(outstring, 0, 3*length+1);
-    for (int i =0; i<length; i++) {
-        sprintf(outstring+i*growth, "%02x ", input[i]);
-    }
-    return outstring;
-}
-
 /*
  * Encrypt message using crypto_secretbox_easy().
  *
@@ -194,14 +184,10 @@ int sodium_crypto_box_seal(uschar **yield, int argc, uschar *argv[]) {
         return ERROR;
     }
 
-    log_write(0, LOG_MAIN, "[encrypt] PK: %s", string2hex(pk, pk_buffer_len));
-
     // get cleartext message
     unsigned char *message = argv[1];
     size_t messagelen = strlen((const char *) message);
 
-    log_write(0, LOG_MAIN, "[encrypt] cleartext: %s", message);
-
     // prepare buffer for ciphertext
     unsigned int cipherlen = messagelen + crypto_box_SEALBYTES;
     unsigned char *ciphertext = store_get(cipherlen);
@@ -213,8 +199,6 @@ int sodium_crypto_box_seal(uschar **yield, int argc, uschar *argv[]) {
         return ERROR;
     }
 
-    log_write(0, LOG_MAIN, "[encrypt] ciphertext: %s", string2hex(ciphertext, cipherlen));
-
     // base64-encode the ciphertext
     unsigned int outputsize = sodium_base64_ENCODED_LEN(cipherlen,
                                                         sodium_base64_VARIANT_ORIGINAL);
@@ -262,7 +246,6 @@ int sodium_crypto_box_seal_open(uschar **yield, int argc, uschar *argv[]) {
         *yield = string_copy((unsigned char *) "Error decoding private key");
         return ERROR;
     }
-    log_write(0, LOG_MAIN, "[decrypt] SK: %s", string2hex(sk, sk_buffer_len));
 
     // get and convert public key
     unsigned char *pkb64 = argv[1];
@@ -280,8 +263,6 @@ int sodium_crypto_box_seal_open(uschar **yield, int argc, uschar *argv[]) {
         return ERROR;
     }
 
-    log_write(0, LOG_MAIN, "[decrypt] PK: %s", string2hex(pk, pk_buffer_len));
-
     // get encrypted message
     unsigned char *ciphertextb64 = argv[2];
     size_t ciphertextb64_len = strlen((const char *) ciphertextb64);
@@ -300,18 +281,12 @@ int sodium_crypto_box_seal_open(uschar **yield, int argc, uschar *argv[]) {
         return ERROR;
     }
 
-    log_write(0, LOG_MAIN, "[encrypt] ciphertext: %s", string2hex(ciphertext, ciphertextlen));
-
     // prepare buffer for cleartext
     unsigned int cleartextlen = ciphertextlen - crypto_box_SEALBYTES;
     unsigned char *cleartext = (unsigned char *) store_get(cleartextlen + 1);
     sodium_memzero(cleartext, cleartextlen + 1);
 
     // decrypt message
-//#define DEBUG
-#ifdef DEBUG
-    log_write(0, LOG_MAIN, "pid: %d", getpid()); int busywait = 0; while (busywait == 0) {}
-#endif
     if (crypto_box_seal_open(cleartext, ciphertext, ciphertextlen, pk, sk) != 0) {
         *yield = string_copy((unsigned char *) "Decryption error after crypto_box_seal_open()");
         return ERROR;