bsd-auth: review fixes, add missing function

1 files changed, 71 insertions, 7 deletions

diff --git a/content/posts/WIP-how-bsd-authentication-works/index.org b/content/posts/WIP-how-bsd-authentication-works/index.org
index 6c211a9..9fd5fdd 100644
--- a/content/posts/WIP-how-bsd-authentication-works/index.org
+++ b/content/posts/WIP-how-bsd-authentication-works/index.org
@@ -424,11 +424,14 @@
    @@html: </details> @@
 
    [[https://man.openbsd.org/auth_subr.3#auth_setitem][=auth_setitem=]] is used to set one of several different fields of
-   =as= to =value=. Depending on the value of =item=, it can be the
-   =challenge=, =class=, =name=, =service=, =style=, or =interactive=
-   field. If =value= is =NULL=, it clears that field. If =item= is
-   =AUTHV_ALL= and =value= is =NULL=, all fields are cleared. It
-   returns =0= on success.
+   =as= to =value=. Depending on the value of =item= ([[#auth_item_t][=auth_item_t=]]), it
+   can be the =challenge=, =class=, =name=, =service=, =style=, or
+   =interactive= field. If =value= is =NULL=, it clears that field. If
+   =item= is =AUTHV_ALL= and =value= is =NULL=, all fields are
+   cleared. It returns =0= on success.
+
+   *Note*: As of writing, the man page displays the incorrect name for
+   the constants.
 
    #+CAPTION: Taken from [[https://man.openbsd.org/auth_subr.3#auth_getitem][=auth_subr(3)=]]
    #+begin_src text
@@ -672,7 +675,7 @@
    #+end_src
    @@html: </details> @@
 
-   [[https://man.openbsd.org/auth_subr.3#auth_set_va_list][=auth_set_va_list=]] copies =ap= to the =ap= field in =as=
+   [[https://man.openbsd.org/auth_subr.3#auth_set_va_list][=auth_set_va_list=]] copies =ap= to =as->ap=.
 
 ** auth_clrenv
    :PROPERTIES:
@@ -932,7 +935,7 @@
    escape sequences in the value, and returns the newly created
    string.
 
-   For convenience, the function [[https://man.openbsd.org/man3/authenticate.3#auth_mkvalue][=auth_mkvalue(3)=]] can be used inside
+   For convenience, the function [[#auth_mkvalue][=auth_mkvalue=]] can be used inside
    of the authentication module to create and return appropriately
    escaped value strings.
 
@@ -2525,6 +2528,67 @@
   [[https://man.openbsd.org/man3/authenticate.3#auth_cat][=auth_cat=]] is a helper function that will write the contents of a
   =file= to =stdout=. It returns =0= on failure or =1= on success.
 
+* auth_mkvalue
+  :PROPERTIES:
+  :CUSTOM_ID: auth_mkvalue
+  :END:
+
+  @@html: <details> <summary> @@
+  #+begin_src c
+  char *auth_mkvalue(char *value)
+  #+end_src
+
+  @@html: </summary> @@
+  #+begin_src c
+  {
+  	char *big, *p;
+
+  	big = malloc(strlen(value) * 4 + 1);
+  	if (big == NULL)
+  		return (NULL);
+  	/*
+  	 ,* XXX - There should be a more standardized
+  	 ,* routine for doing this sort of thing.
+  	 ,*/
+  	for (p = big; *value; ++value) {
+  		switch (*value) {
+  		case '\r':
+  			,*p++ = '\\';
+  			,*p++ = 'r';
+  			break;
+  		case '\n':
+  			,*p++ = '\\';
+  			,*p++ = 'n';
+  			break;
+  		case '\\':
+  			,*p++ = '\\';
+  			,*p++ = *value;
+  			break;
+  		case '\t':
+  		case ' ':
+  			if (p == big)
+  				,*p++ = '\\';
+  			,*p++ = *value;
+  			break;
+  		default:
+  			if (!isprint((unsigned char)*value)) {
+  				,*p++ = '\\';
+  				,*p++ = ((*value >> 6) & 0x3) + '0';
+  				,*p++ = ((*value >> 3) & 0x7) + '0';
+  				,*p++ = ((*value     ) & 0x7) + '0';
+  			} else
+  				,*p++ = *value;
+  			break;
+  		}
+  	}
+  	,*p = '\0';
+  	return (big);
+  }
+  #+end_src
+  @@html: </details> @@
+
+  [[https://man.openbsd.org/authenticate.3#auth_mkvalue][=auth_mkvalue=]] creates an escaped string which can be decoded by [[#auth_getvalue][=auth_getvalue=]].
+
 * _auth_validuser
   :PROPERTIES:
   :CUSTOM_ID: _auth_validuser