htrules.c

用于linux和其他unix下面的

/*	Configuration manager for Hypertext Daemon		HTRules.c
**	==========================================
**
**
** History:
**	 3 Jun 91	Written TBL
**	10 Aug 91	Authorisation added after Daniel Martin (pass, fail)
**			Rule order in file changed
**			Comments allowed with # on 1st char of rule line
**	17 Jun 92	Bug fix: pass and fail failed if didn't contain '*' TBL
**	 1 Sep 93	Bug fix: no memory check - Nathan Torkington
**			BYTE_ADDRESSING removed - Arthur Secret
**	11 Sep 93  MD	Changed %i into %d in debug printf.
**			VMS does not recognize %i.
**			Bug Fix: in case of PASS, only one parameter to printf.
**	19 Sep 93  AL	Added Access Authorization stuff.
**	 1 Nov 93  AL	Added htbin.
**	25 May 99  KW	Added redirect for lynx.
**
*/

#include <HTUtils.h>

/* (c) CERN WorldWideWeb project 1990,91. See Copyright.html for details */
#include <HTRules.h>

#include <HTFile.h>
#include <LYLeaks.h>
#include <HTAAProt.h>

#define LINE_LENGTH 256


typedef struct _rule {
	struct _rule *	next;
	HTRuleOp	op;
	char *		pattern;
	char *		equiv;
	char *		condition_op; /* as strings - may be inefficient, */
	char *		condition;    /* but this is not for a server - kw */
} rule;

#ifndef NO_RULES

#include <HTTP.h> /* for redirecting_url, indirectly HTPermitRedir - kw */
#include <LYGlobalDefs.h> /* for LYUserSpecifiedURL - kw */
#include <LYUtils.h>		/* for LYFixCursesOn - kw */
#include <HTAlert.h>

/*	Global variables
**	----------------
*/
PUBLIC char *HTBinDir = NULL;	/* Physical /htbin directory path.	*/
				/* In future this should not be global. */
PUBLIC char *HTSearchScript = NULL;	/* Search script name.		*/


/*	Module-wide variables
**	---------------------
*/

PRIVATE rule * rules = 0;	/* Pointer to first on list */
#ifndef PUT_ON_HEAD
PRIVATE rule * rule_tail = 0;	/* Pointer to last on list */
#endif


/*	Add rule to the list					HTAddRule()
**	--------------------
**
**  On entry,
**	pattern		points to 0-terminated string containing a single "*"
**	equiv		points to the equivalent string with * for the
**			place where the text matched by * goes.
**  On exit,
**	returns		0 if success, -1 if error.
*/

PUBLIC int HTAddRule ARGS5(
    HTRuleOp,		op,
    CONST char *,	pattern,
    CONST char *,	equiv,
    CONST char *,	cond_op,
    CONST char *,	cond)
{ /* BYTE_ADDRESSING removed and memory check - AS - 1 Sep 93 */
    rule *	temp;
    char *	pPattern = NULL;

    temp = typecalloc(rule);
    if (temp==NULL)
	outofmem(__FILE__, "HTAddRule");
    if (equiv) {		/* Two operands */
	char *	pEquiv = NULL;
	StrAllocCopy(pEquiv, equiv);
	temp->equiv = pEquiv;
    } else {
	temp->equiv = 0;
    }
    if (cond_op) {
	StrAllocCopy(temp->condition_op, cond_op);
	StrAllocCopy(temp->condition, cond);
    }
    StrAllocCopy(pPattern, pattern);
    temp->pattern = pPattern;
    temp->op = op;

    if (equiv) {
	CTRACE((tfp, "Rule: For `%s' op %d `%s'", pattern, op, equiv));
    } else {
	CTRACE((tfp, "Rule: For `%s' op %d", pattern, op));
    }
    if (cond_op) {
	CTRACE((tfp, "\t%s %s\n", cond_op, NONNULL(cond)));
    } else {
	CTRACE((tfp, "\n"));
    }

    if (!rules) {
#ifdef LY_FIND_LEAKS
	atexit(HTClearRules);
#endif
    }
#ifdef PUT_ON_HEAD
    temp->next = rules;
    rules = temp;
#else
    temp->next = 0;
    if (rule_tail) rule_tail->next = temp;
    else rules = temp;
    rule_tail = temp;
#endif


    return 0;
}


/*	Clear all rules						HTClearRules()
**	---------------
**
** On exit,
**	There are no rules
**
** See also
**	HTAddRule()
*/
void HTClearRules NOARGS
{
    while (rules) {
	rule * temp = rules;
	rules = temp->next;
	FREE(temp->pattern);
	FREE(temp->equiv);
	FREE(temp->condition_op);
	FREE(temp->condition);
	FREE(temp);
    }
#ifndef PUT_ON_HEAD
    rule_tail = 0;
#endif
}

PRIVATE BOOL rule_cond_ok ARGS1(
    rule *,	 r)
{
    BOOL result;
    if (!r->condition_op)
	return YES;
    if (strcmp(r->condition_op, "if") && strcmp(r->condition_op, "unless")) {
	CTRACE((tfp, "....... rule ignored, unrecognized `%s'!\n",
	       r->condition_op));
	return NO;
    }
    if (!strcmp(r->condition, "redirected"))
	result = (BOOL) (redirection_attempts > 0);
    else if (!strcmp(r->condition, "userspec"))
	result = LYUserSpecifiedURL;
    else {
	CTRACE((tfp, "....... rule ignored, unrecognized `%s %s'!\n",
	       r->condition_op, NONNULL(r->condition)));
	return NO;
    }
    if (!strcmp(r->condition_op, "if"))
	return result;
    else
	return (BOOL) (!result);

}
/*	Translate by rules					HTTranslate()
**	------------------
**
**	The most recently defined rules are applied first.
**
** On entry,
**	required	points to a string whose equivalent value is neeed
** On exit,
**	returns		the address of the equivalent string allocated from
**			the heap which the CALLER MUST FREE. If no translation
**			occured, then it is a copy of te original.
** NEW FEATURES:
**			When a "protect" or "defprot" rule is mathed,
**			a call to HTAA_setCurrentProtection() or
**			HTAA_setDefaultProtection() is made to notify
**			the Access Authorization module that the file is
**			protected, and so it knows how to handle it.
**								-- AL
*/
char * HTTranslate ARGS1(
    CONST char *,	required)
{
    rule * r;
    char *current = NULL;
    char *msgtmp = NULL, *pMsg;
    int proxy_none_flag = 0;
    int permitredir_flag = 0;
    StrAllocCopy(current, required);

    HTAA_clearProtections();	/* Reset from previous call -- AL */

    for(r = rules; r; r = r->next) {
	char * p = r->pattern;
	int m=0;   /* Number of characters matched against wildcard */
	CONST char * q = current;
	for(;*p && *q; p++, q++) {   /* Find first mismatch */
	    if (*p!=*q) break;
	}

	if (*p == '*') {		/* Match up to wildcard */
	    m = strlen(q) - strlen(p+1); /* Amount to match to wildcard */
	    if(m<0) continue;		/* tail is too short to match */
	    if (0!=strcmp(q+m, p+1)) continue;	/* Tail mismatch */
	} else				/* Not wildcard */
	    if (*p != *q) continue;	/* plain mismatch: go to next rule */

	if (!rule_cond_ok(r))	/* check condition, next rule if false - kw */
	    continue;

	switch (r->op) {		/* Perform operation */

#ifdef ACCESS_AUTH
	case HT_DefProt:
	case HT_Protect:
	    {
		char *local_copy = NULL;
		char *p2;
		char *eff_ids = NULL;
		char *prot_file = NULL;

		CTRACE((tfp, "HTRule: `%s' matched %s %s: `%s'\n",
			    current,
			    (r->op==HT_Protect ? "Protect" : "DefProt"),
			    "rule, setup",
			    (r->equiv ? r->equiv :
			     (r->op==HT_Protect ?"DEFAULT" :"NULL!!"))));

		if (r->equiv) {
		    StrAllocCopy(local_copy, r->equiv);
		    p2 = local_copy;
		    prot_file = HTNextField(&p2);
		    eff_ids = HTNextField(&p2);
		}

		if (r->op == HT_Protect)
		    HTAA_setCurrentProtection(current, prot_file, eff_ids);
		else
		    HTAA_setDefaultProtection(current, prot_file, eff_ids);

		FREE(local_copy);

		/* continue translating rules */
	    }
	    break;
#endif /* ACCESS_AUTH */

	case HT_UserMsg:		/* Produce message immediately */
	    LYFixCursesOn("show rule message:");
	    HTUserMsg2((r->equiv ? r->equiv : "Rule: %s"), current);
	    break;
	case HT_InfoMsg:		/* Produce messages immediately */
	case HT_Progress:
	case HT_Alert:
	    LYFixCursesOn("show rule message:"); /* and fall through */
	case HT_AlwaysAlert:
	    pMsg = r->equiv ? r->equiv :
		(r->op==HT_AlwaysAlert) ? "%s" : "Rule: %s";
	    if (strchr(pMsg, '%')) {
		HTSprintf0(&msgtmp, pMsg, current);
		pMsg = msgtmp;
	    }
	    switch (r->op) {		/* Actually produce message */
	    case HT_InfoMsg:	HTInfoMsg(pMsg);	break;
	    case HT_Progress:	HTProgress(pMsg);	break;
	    case HT_Alert:	HTAlert(pMsg);		break;
	    case HT_AlwaysAlert: HTAlwaysAlert("Rule alert:", pMsg);	break;
	    default: break;
	    }
	    FREE(msgtmp);
	    break;

	case HT_PermitRedir:			/* Set special flag */
	    permitredir_flag = 1;
	    CTRACE((tfp, "HTRule: Mark for redirection permitted\n"));
	    break;

	case HT_Pass:				/* Authorised */
	    if (!r->equiv) {
		if (proxy_none_flag) {
		    char * temp = NULL;
		    StrAllocCopy(temp, "NoProxy=");
		    StrAllocCat(temp, current);
		    FREE(current);
		    current = temp;
		}
		CTRACE((tfp, "HTRule: Pass `%s'\n", current));
		return current;
	    }
	    /* Else fall through ...to map and pass */

	case HT_Map:
	case HT_Redirect:
	case HT_RedirectPerm:
	    if (*p == *q) { /* End of both strings, no wildcard */
		  CTRACE((tfp, "For `%s' using `%s'\n", current, r->equiv));
		  StrAllocCopy(current, r->equiv); /* use entire translation */