X-Git-Url: https://git.distorted.org.uk/~mdw/fwd/blobdiff_plain/e82f7154f65062d9ac8b9677862774498b331058..bdbbfcd4eb2f6e15270f558342630d964cb9f418:/acl.c diff --git a/acl.c b/acl.c index 4dadc24..29dd2db 100644 --- a/acl.c +++ b/acl.c @@ -1,10 +1,10 @@ /* -*-c-*- * - * $Id: acl.c,v 1.1 1999/07/01 08:56:23 mdw Exp $ + * $Id: acl.c,v 1.4 2003/11/25 14:08:23 mdw Exp $ * * Access control list handling * - * (c) 1999 Mark Wooding + * (c) 1999 Straylight/Edgeware */ /*----- Licensing notice --------------------------------------------------* @@ -29,8 +29,17 @@ /*----- Revision history --------------------------------------------------* * * $Log: acl.c,v $ - * Revision 1.1 1999/07/01 08:56:23 mdw - * Initial revision + * Revision 1.4 2003/11/25 14:08:23 mdw + * Debianization. Socket target options. Internet binding. + * + * Revision 1.3 1999/07/27 18:30:53 mdw + * Various minor portability fixes. + * + * Revision 1.2 1999/07/26 23:28:15 mdw + * Minor modifications for new design. + * + * Revision 1.1.1.1 1999/07/01 08:56:23 mdw + * Initial revision. * */ @@ -43,6 +52,9 @@ #include #include +#include +#include + #include #include #include @@ -52,38 +64,122 @@ #include "acl.h" -/*----- Static variables --------------------------------------------------*/ +/*----- Main code ---------------------------------------------------------*/ -static acl_entry *global = 0; -static acl_entry **gtail = &global; +/* --- @acl_addhost@ --- * + * + * Arguments: @acl_entry ***a@ = address of pointer to list tail + * @unsigned act@ = what to do with matching addresses + * @struct in_addr addr, mask@ = address and mask to match + * + * Returns: --- + * + * Use: Adds a host-authentication entry to the end of an access + * control list. + */ -/*----- Main code ---------------------------------------------------------*/ +static int acl_checkhost(void *aa, struct in_addr addr, unsigned port) +{ + acl_host *a = aa; + return ((addr.s_addr & a->mask.s_addr) == a->addr.s_addr); +} + +static void acl_dumphost(void *aa, FILE *fp) +{ + acl_host *a = aa; + + fputs("from ", fp); + fputs(inet_ntoa(a->addr), fp); + fputc('/', fp); + fputs(inet_ntoa(a->mask), fp); +} + +static void acl_freehost(void *aa) +{ + acl_host *a = aa; + DESTROY(a); +} + +static const acl_ops acl_hostops = { + acl_checkhost, acl_dumphost, acl_freehost +}; + +void acl_addhost(acl_entry ***a, unsigned act, + struct in_addr addr, struct in_addr mask) +{ + acl_host *aa = CREATE(acl_host); + aa->a.next = 0; + aa->a.ops = &acl_hostops; + aa->a.act = act; + aa->addr.s_addr = addr.s_addr & mask.s_addr; + aa->mask = mask; + **a = &aa->a; + *a = &aa->a.next; +} + +/* --- @acl_addpriv@ --- * + * + * Arguments: @acl_entry ***a@ = address of pointer to list tail + * @unsigned act@ = what to do with matching addresses + * + * Returns: --- + * + * Use: Adds a privileged-port check to the end of an access control + * list. + */ + +static int acl_checkpriv(void *aa, struct in_addr addr, unsigned port) +{ + return (port < 1024); +} + +static void acl_dumppriv(void *aa, FILE *fp) +{ + fputs("from privileged ports", fp); +} + +static void acl_freepriv(void *aa) +{ + acl_entry *a = aa; + DESTROY(a); +} + +static const acl_ops acl_privops = { + acl_checkpriv, acl_dumppriv, acl_freepriv +}; + +void acl_addpriv(acl_entry ***a, unsigned act) +{ + acl_entry *aa = CREATE(acl_entry); + aa->next = 0; + aa->ops = &acl_privops; + aa->act = act; + **a = aa; + *a = &aa->next; +} /* --- @acl_check@ --- * * * Arguments: @acl_entry *a@ = pointer to ACL to check against * @struct in_addr addr@ = address to check + * @unsigned port@ = port number to check + * @int *act@ = verdict (should initially be @ACT_ALLOW@) * - * Returns: Nonzero if allowed. + * Returns: Zero if undecided, nonzero if a rule matched. * * Use: Checks an address against an ACL. */ -int acl_check(acl_entry *a, struct in_addr addr) +int acl_check(acl_entry *a, struct in_addr addr, unsigned port, int *act) { - int act = ACL_ALLOW; - int i; - - for (i = 0; i < 2; i++) { - for (; a; a = a->next) { - if ((addr.s_addr & a->mask.s_addr) == a->addr.s_addr) - return (a->act & ACL_PERM); - act = (a->act & ACL_PERM) ^ 1; + for (; a; a = a->next) { + if (a->ops->check(a, addr, port)) { + *act = a->act & ACL_PERM; + return (1); } - a = global; + *act = (a->act & ACL_PERM) ^ 1; } - - return (act); + return (0); } /* --- @acl_dump@ --- * @@ -98,41 +194,30 @@ int acl_check(acl_entry *a, struct in_addr addr) void acl_dump(acl_entry *a, FILE *fp) { - if (!a) - a = global; for (; a; a = a->next) { - fprintf(fp, " %s from ", + fprintf(fp, " %s ", (a->act & ACL_PERM) == ACL_ALLOW ? "allow" : "deny"); - fputs(inet_ntoa(a->addr), fp); - fputc('/', fp); - fputs(inet_ntoa(a->mask), fp); + a->ops->dump(a, fp); fputc('\n', fp); } } -/* --- @acl_add@ --- * +/* --- @acl_free@ --- * * - * Arguments: @acl_entry ***a@ = address of pointer to list tail - * @unsigned act@ = what to do with matching addresses - * @struct in_addr addr, mask@ = address and mask to match + * Arguments: @acl_entry *a@ = pointer to a list of ACLs * * Returns: --- * - * Use: Adds an entry to the end of an access control list. + * Use: Frees all of the memory used by an ACL. */ -void acl_add(acl_entry ***a, unsigned act, - struct in_addr addr, struct in_addr mask) +void acl_free(acl_entry *a) { - acl_entry *aa = CREATE(acl_entry); - aa->act = act; - aa->addr.s_addr = addr.s_addr & mask.s_addr; - aa->mask = mask; - aa->next = 0; - if (!a) - a = >ail; - **a = aa; - *a = &aa->next; + while (a) { + acl_entry *aa = a; + a = a->next; + aa->ops->free(aa); + } } /*----- That's all, folks -------------------------------------------------*/