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-rw-r--r--doc/crypto/CONF_modules_load_file.pod87
1 files changed, 82 insertions, 5 deletions
diff --git a/doc/crypto/CONF_modules_load_file.pod b/doc/crypto/CONF_modules_load_file.pod
index 0c4d926858fb..cc0b537b8ea5 100644
--- a/doc/crypto/CONF_modules_load_file.pod
+++ b/doc/crypto/CONF_modules_load_file.pod
@@ -9,9 +9,9 @@
#include <openssl/conf.h>
int CONF_modules_load_file(const char *filename, const char *appname,
- unsigned long flags);
+ unsigned long flags);
int CONF_modules_load(const CONF *cnf, const char *appname,
- unsigned long flags);
+ unsigned long flags);
=head1 DESCRIPTION
@@ -22,7 +22,7 @@ NULL the standard OpenSSL application name B<openssl_conf> is used.
The behaviour can be cutomized using B<flags>.
CONF_modules_load() is idential to CONF_modules_load_file() except it
-read configuration information from B<cnf>.
+reads configuration information from B<cnf>.
=head1 NOTES
@@ -30,7 +30,7 @@ The following B<flags> are currently recognized:
B<CONF_MFLAGS_IGNORE_ERRORS> if set errors returned by individual
configuration modules are ignored. If not set the first module error is
-considered fatal and no further modules are loads.
+considered fatal and no further modules are loaded.
Normally any modules errors will add error information to the error queue. If
B<CONF_MFLAGS_SILENT> is set no error information is added.
@@ -42,7 +42,84 @@ B<CONF_MFLAGS_IGNORE_MISSING_FILE> if set will make CONF_load_modules_file()
ignore missing configuration files. Normally a missing configuration file
return an error.
-=head1 RETURN VALUE
+B<CONF_MFLAGS_DEFAULT_SECTION> if set and B<appname> is not NULL will use the
+default section pointed to by B<openssl_conf> if B<appname> does not exist.
+
+Applications should call these functions after loading builtin modules using
+OPENSSL_load_builtin_modules(), any ENGINEs for example using
+ENGINE_load_builtin_engines(), any algorithms for example
+OPENSSL_add_all_algorithms() and (if the application uses libssl)
+SSL_library_init().
+
+By using CONF_modules_load_file() with appropriate flags an application can
+customise application configuration to best suit its needs. In some cases the
+use of a configuration file is optional and its absence is not an error: in
+this case B<CONF_MFLAGS_IGNORE_MISSING_FILE> would be set.
+
+Errors during configuration may also be handled differently by different
+applications. For example in some cases an error may simply print out a warning
+message and the application continue. In other cases an application might
+consider a configuration file error as fatal and exit immediately.
+
+Applications can use the CONF_modules_load() function if they wish to load a
+configuration file themselves and have finer control over how errors are
+treated.
+
+=head1 EXAMPLES
+
+Load a configuration file and print out any errors and exit (missing file
+considered fatal):
+
+ if (CONF_modules_load_file(NULL, NULL, 0) <= 0) {
+ fprintf(stderr, "FATAL: error loading configuration file\n");
+ ERR_print_errors_fp(stderr);
+ exit(1);
+ }
+
+Load default configuration file using the section indicated by "myapp",
+tolerate missing files, but exit on other errors:
+
+ if (CONF_modules_load_file(NULL, "myapp",
+ CONF_MFLAGS_IGNORE_MISSING_FILE) <= 0) {
+ fprintf(stderr, "FATAL: error loading configuration file\n");
+ ERR_print_errors_fp(stderr);
+ exit(1);
+ }
+
+Load custom configuration file and section, only print warnings on error,
+missing configuration file ignored:
+
+ if (CONF_modules_load_file("/something/app.cnf", "myapp",
+ CONF_MFLAGS_IGNORE_MISSING_FILE) <= 0) {
+ fprintf(stderr, "WARNING: error loading configuration file\n");
+ ERR_print_errors_fp(stderr);
+ }
+
+Load and parse configuration file manually, custom error handling:
+
+ FILE *fp;
+ CONF *cnf = NULL;
+ long eline;
+ fp = fopen("/somepath/app.cnf", "r");
+ if (fp == NULL) {
+ fprintf(stderr, "Error opening configuration file\n");
+ /* Other missing configuration file behaviour */
+ } else {
+ cnf = NCONF_new(NULL);
+ if (NCONF_load_fp(cnf, fp, &eline) == 0) {
+ fprintf(stderr, "Error on line %ld of configuration file\n", eline);
+ ERR_print_errors_fp(stderr);
+ /* Other malformed configuration file behaviour */
+ } else if (CONF_modules_load(cnf, "appname", 0) <= 0) {
+ fprintf(stderr, "Error configuring application\n");
+ ERR_print_errors_fp(stderr);
+ /* Other configuration error behaviour */
+ }
+ fclose(fp);
+ NCONF_free(cnf);
+ }
+
+=head1 RETURN VALUES
These functions return 1 for success and a zero or negative value for
failure. If module errors are not ignored the return code will reflect the