/* * ACL management functions. * * Copyright 2000-2013 Willy Tarreau * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* List head of all known ACL keywords */ static struct acl_kw_list acl_keywords = { .list = LIST_HEAD_INIT(acl_keywords.list) }; /* input values are 0 or 3, output is the same */ static inline enum acl_test_res pat2acl(struct pattern *pat) { if (pat) return ACL_TEST_PASS; else return ACL_TEST_FAIL; } /* * Registers the ACL keyword list as a list of valid keywords for next * parsing sessions. */ void acl_register_keywords(struct acl_kw_list *kwl) { LIST_APPEND(&acl_keywords.list, &kwl->list); } /* * Unregisters the ACL keyword list from the list of valid keywords. */ void acl_unregister_keywords(struct acl_kw_list *kwl) { LIST_DELETE(&kwl->list); LIST_INIT(&kwl->list); } /* Return a pointer to the ACL within the list starting at , or * NULL if not found. */ struct acl *find_acl_by_name(const char *name, struct list *head) { struct acl *acl; list_for_each_entry(acl, head, list) { if (strcmp(acl->name, name) == 0) return acl; } return NULL; } /* Return a pointer to the ACL keyword , or NULL if not found. Note that if * contains an opening parenthesis or a comma, only the left part of it is * checked. */ struct acl_keyword *find_acl_kw(const char *kw) { int index; const char *kwend; struct acl_kw_list *kwl; kwend = kw; while (is_idchar(*kwend)) kwend++; list_for_each_entry(kwl, &acl_keywords.list, list) { for (index = 0; kwl->kw[index].kw != NULL; index++) { if ((strncmp(kwl->kw[index].kw, kw, kwend - kw) == 0) && kwl->kw[index].kw[kwend-kw] == 0) return &kwl->kw[index]; } } return NULL; } static struct acl_expr *prune_acl_expr(struct acl_expr *expr) { struct arg *arg; pattern_prune(&expr->pat); for (arg = expr->smp->arg_p; arg; arg++) { if (arg->type == ARGT_STOP) break; if (arg->type == ARGT_STR || arg->unresolved) { chunk_destroy(&arg->data.str); arg->unresolved = 0; } } release_sample_expr(expr->smp); return expr; } /* Parse an ACL expression starting at [0], and return it. If is * not NULL, it will be filled with a pointer to an error message in case of * error. This pointer must be freeable or NULL. is an arg_list serving * as a list head to report missing dependencies. It may be NULL if such * dependencies are not allowed. * * Right now, the only accepted syntax is : * [...] */ struct acl_expr *parse_acl_expr(const char **args, char **err, struct arg_list *al, const char *file, int line) { __label__ out_return, out_free_expr; struct acl_expr *expr; struct acl_keyword *aclkw; int refflags, patflags; const char *arg; struct sample_expr *smp = NULL; int idx = 0; char *ckw = NULL; const char *endt; int cur_type; int nbargs; int operator = STD_OP_EQ; int op; int contain_colon, have_dot; const char *dot; signed long long value, minor; /* The following buffer contain two numbers, a ':' separator and the final \0. */ char buffer[NB_LLMAX_STR + 1 + NB_LLMAX_STR + 1]; int is_loaded; int unique_id; char *error; struct pat_ref *ref; struct pattern_expr *pattern_expr; int load_as_map = 0; int acl_conv_found = 0; /* First, we look for an ACL keyword. And if we don't find one, then * we look for a sample fetch expression starting with a sample fetch * keyword. */ if (al) { al->ctx = ARGC_ACL; // to report errors while resolving args late al->kw = *args; al->conv = NULL; } aclkw = find_acl_kw(args[0]); if (aclkw) { /* OK we have a real ACL keyword */ /* build new sample expression for this ACL */ smp = calloc(1, sizeof(*smp)); if (!smp) { memprintf(err, "out of memory when parsing ACL expression"); goto out_return; } LIST_INIT(&(smp->conv_exprs)); smp->fetch = aclkw->smp; smp->arg_p = empty_arg_list; /* look for the beginning of the subject arguments */ for (arg = args[0]; is_idchar(*arg); arg++) ; /* At this point, we have : * - args[0] : beginning of the keyword * - arg : end of the keyword, first character not part of keyword */ nbargs = make_arg_list(arg, -1, smp->fetch->arg_mask, &smp->arg_p, err, &endt, NULL, al); if (nbargs < 0) { /* note that make_arg_list will have set here */ memprintf(err, "ACL keyword '%s' : %s", aclkw->kw, *err); goto out_free_smp; } if (!smp->arg_p) { smp->arg_p = empty_arg_list; } else if (smp->fetch->val_args && !smp->fetch->val_args(smp->arg_p, err)) { /* invalid keyword argument, error must have been * set by val_args(). */ memprintf(err, "in argument to '%s', %s", aclkw->kw, *err); goto out_free_smp; } /* look for the beginning of the converters list. Those directly attached * to the ACL keyword are found just after the comma. * If we find any converter, then we don't use the ACL keyword's match * anymore but the one related to the converter's output type. */ if (!sample_parse_expr_cnv((char **)args, NULL, NULL, err, al, file, line, smp, endt)) { if (err) memprintf(err, "ACL keyword '%s' : %s", aclkw->kw, *err); goto out_free_smp; } acl_conv_found = !LIST_ISEMPTY(&smp->conv_exprs); } else { /* This is not an ACL keyword, so we hope this is a sample fetch * keyword that we're going to transparently use as an ACL. If * so, we retrieve a completely parsed expression with args and * convs already done. */ smp = sample_parse_expr((char **)args, &idx, file, line, err, al, NULL); if (!smp) { memprintf(err, "%s in ACL expression '%s'", *err, *args); goto out_return; } } /* get last effective output type for smp */ cur_type = smp_expr_output_type(smp); expr = calloc(1, sizeof(*expr)); if (!expr) { memprintf(err, "out of memory when parsing ACL expression"); goto out_free_smp; } pattern_init_head(&expr->pat); expr->pat.expect_type = cur_type; expr->smp = smp; expr->kw = smp->fetch->kw; smp = NULL; /* don't free it anymore */ if (aclkw && !acl_conv_found) { expr->kw = aclkw->kw; expr->pat.parse = aclkw->parse ? aclkw->parse : pat_parse_fcts[aclkw->match_type]; expr->pat.index = aclkw->index ? aclkw->index : pat_index_fcts[aclkw->match_type]; expr->pat.match = aclkw->match ? aclkw->match : pat_match_fcts[aclkw->match_type]; expr->pat.prune = aclkw->prune ? aclkw->prune : pat_prune_fcts[aclkw->match_type]; } if (!expr->pat.parse) { /* Parse/index/match functions depend on the expression type, * so we have to map them now. Some types can be automatically * converted. */ switch (cur_type) { case SMP_T_BOOL: expr->pat.parse = pat_parse_fcts[PAT_MATCH_BOOL]; expr->pat.index = pat_index_fcts[PAT_MATCH_BOOL]; expr->pat.match = pat_match_fcts[PAT_MATCH_BOOL]; expr->pat.prune = pat_prune_fcts[PAT_MATCH_BOOL]; expr->pat.expect_type = pat_match_types[PAT_MATCH_BOOL]; break; case SMP_T_SINT: expr->pat.parse = pat_parse_fcts[PAT_MATCH_INT]; expr->pat.index = pat_index_fcts[PAT_MATCH_INT]; expr->pat.match = pat_match_fcts[PAT_MATCH_INT]; expr->pat.prune = pat_prune_fcts[PAT_MATCH_INT]; expr->pat.expect_type = pat_match_types[PAT_MATCH_INT]; break; case SMP_T_ADDR: case SMP_T_IPV4: case SMP_T_IPV6: expr->pat.parse = pat_parse_fcts[PAT_MATCH_IP]; expr->pat.index = pat_index_fcts[PAT_MATCH_IP]; expr->pat.match = pat_match_fcts[PAT_MATCH_IP]; expr->pat.prune = pat_prune_fcts[PAT_MATCH_IP]; expr->pat.expect_type = pat_match_types[PAT_MATCH_IP]; break; case SMP_T_STR: expr->pat.parse = pat_parse_fcts[PAT_MATCH_STR]; expr->pat.index = pat_index_fcts[PAT_MATCH_STR]; expr->pat.match = pat_match_fcts[PAT_MATCH_STR]; expr->pat.prune = pat_prune_fcts[PAT_MATCH_STR]; expr->pat.expect_type = pat_match_types[PAT_MATCH_STR]; break; } } /* Additional check to protect against common mistakes */ if (expr->pat.parse && cur_type != SMP_T_BOOL && !*args[1]) { ha_warning("parsing acl keyword '%s' :\n" " no pattern to match against were provided, so this ACL will never match.\n" " If this is what you intended, please add '--' to get rid of this warning.\n" " If you intended to match only for existence, please use '-m found'.\n" " If you wanted to force an int to match as a bool, please use '-m bool'.\n" "\n", args[0]); } args++; /* check for options before patterns. Supported options are : * -i : ignore case for all patterns by default * -f : read patterns from those files * -m : force matching method (must be used before -f) * -M : load the file as map file * -u : force the unique id of the acl * -- : everything after this is not an option */ refflags = PAT_REF_ACL; patflags = 0; is_loaded = 0; unique_id = -1; while (**args == '-') { if (strcmp(*args, "-i") == 0) patflags |= PAT_MF_IGNORE_CASE; else if (strcmp(*args, "-n") == 0) patflags |= PAT_MF_NO_DNS; else if (strcmp(*args, "-u") == 0) { unique_id = strtol(args[1], &error, 10); if (*error != '\0') { memprintf(err, "the argument of -u must be an integer"); goto out_free_expr; } /* Check if this id is really unique. */ if (pat_ref_lookupid(unique_id)) { memprintf(err, "the id is already used"); goto out_free_expr; } args++; } else if (strcmp(*args, "-f") == 0) { if (!expr->pat.parse) { memprintf(err, "matching method must be specified first (using '-m') when using a sample fetch of this type ('%s')", expr->kw); goto out_free_expr; } if (!pattern_read_from_file(&expr->pat, refflags, args[1], patflags, load_as_map, err, file, line)) goto out_free_expr; is_loaded = 1; args++; } else if (strcmp(*args, "-m") == 0) { int idx; if (is_loaded) { memprintf(err, "'-m' must only be specified before patterns and files in parsing ACL expression"); goto out_free_expr; } idx = pat_find_match_name(args[1]); if (idx < 0) { memprintf(err, "unknown matching method '%s' when parsing ACL expression", args[1]); goto out_free_expr; } /* Note: -m found is always valid, bool/int are compatible, str/bin/reg/len are compatible */ if (idx != PAT_MATCH_FOUND && !sample_casts[cur_type][pat_match_types[idx]]) { memprintf(err, "matching method '%s' cannot be used with fetch keyword '%s'", args[1], expr->kw); goto out_free_expr; } expr->pat.parse = pat_parse_fcts[idx]; expr->pat.index = pat_index_fcts[idx]; expr->pat.match = pat_match_fcts[idx]; expr->pat.prune = pat_prune_fcts[idx]; expr->pat.expect_type = pat_match_types[idx]; args++; } else if (strcmp(*args, "-M") == 0) { refflags |= PAT_REF_MAP; load_as_map = 1; } else if (strcmp(*args, "--") == 0) { args++; break; } else { memprintf(err, "'%s' is not a valid ACL option. Please use '--' before any pattern beginning with a '-'", args[0]); goto out_free_expr; break; } args++; } if (!expr->pat.parse) { memprintf(err, "matching method must be specified first (using '-m') when using a sample fetch of this type ('%s')", expr->kw); goto out_free_expr; } /* Create displayed reference */ snprintf(trash.area, trash.size, "acl '%s' file '%s' line %d", expr->kw, file, line); trash.area[trash.size - 1] = '\0'; /* Create new pattern reference. */ ref = pat_ref_newid(unique_id, trash.area, PAT_REF_ACL); if (!ref) { memprintf(err, "memory error"); goto out_free_expr; } /* Create new pattern expression associated to this reference. */ pattern_expr = pattern_new_expr(&expr->pat, ref, patflags, err, NULL); if (!pattern_expr) goto out_free_expr; /* now parse all patterns */ while (**args) { arg = *args; /* Compatibility layer. Each pattern can parse only one string per pattern, * but the pat_parser_int() and pat_parse_dotted_ver() parsers were need * optionally two operators. The first operator is the match method: eq, * le, lt, ge and gt. pat_parse_int() and pat_parse_dotted_ver() functions * can have a compatibility syntax based on ranges: * * pat_parse_int(): * * "eq x" -> "x" or "x:x" * "le x" -> ":x" * "lt x" -> ":y" (with y = x - 1) * "ge x" -> "x:" * "gt x" -> "y:" (with y = x + 1) * * pat_parse_dotted_ver(): * * "eq x.y" -> "x.y" or "x.y:x.y" * "le x.y" -> ":x.y" * "lt x.y" -> ":w.z" (with w.z = x.y - 1) * "ge x.y" -> "x.y:" * "gt x.y" -> "w.z:" (with w.z = x.y + 1) * * If y is not present, assume that is "0". * * The syntax eq, le, lt, ge and gt are proper to the acl syntax. The * following block of code detect the operator, and rewrite each value * in parsable string. */ if (expr->pat.parse == pat_parse_int || expr->pat.parse == pat_parse_dotted_ver) { /* Check for operator. If the argument is operator, memorise it and * continue to the next argument. */ op = get_std_op(arg); if (op != -1) { operator = op; args++; continue; } /* Check if the pattern contain ':' or '-' character. */ contain_colon = (strchr(arg, ':') || strchr(arg, '-')); /* If the pattern contain ':' or '-' character, give it to the parser as is. * If no contain ':' and operator is STD_OP_EQ, give it to the parser as is. * In other case, try to convert the value according with the operator. */ if (!contain_colon && operator != STD_OP_EQ) { /* Search '.' separator. */ dot = strchr(arg, '.'); if (!dot) { have_dot = 0; minor = 0; dot = arg + strlen(arg); } else have_dot = 1; /* convert the integer minor part for the pat_parse_dotted_ver() function. */ if (expr->pat.parse == pat_parse_dotted_ver && have_dot) { if (strl2llrc(dot+1, strlen(dot+1), &minor) != 0) { memprintf(err, "'%s' is neither a number nor a supported operator", arg); goto out_free_expr; } if (minor >= 65536) { memprintf(err, "'%s' contains too large a minor value", arg); goto out_free_expr; } } /* convert the integer value for the pat_parse_int() function, and the * integer major part for the pat_parse_dotted_ver() function. */ if (strl2llrc(arg, dot - arg, &value) != 0) { memprintf(err, "'%s' is neither a number nor a supported operator", arg); goto out_free_expr; } if (expr->pat.parse == pat_parse_dotted_ver) { if (value >= 65536) { memprintf(err, "'%s' contains too large a major value", arg); goto out_free_expr; } value = (value << 16) | (minor & 0xffff); } switch (operator) { case STD_OP_EQ: /* this case is not possible. */ memprintf(err, "internal error"); goto out_free_expr; case STD_OP_GT: value++; /* gt = ge + 1 */ __fallthrough; case STD_OP_GE: if (expr->pat.parse == pat_parse_int) snprintf(buffer, NB_LLMAX_STR+NB_LLMAX_STR+2, "%lld:", value); else snprintf(buffer, NB_LLMAX_STR+NB_LLMAX_STR+2, "%lld.%lld:", value >> 16, value & 0xffff); arg = buffer; break; case STD_OP_LT: value--; /* lt = le - 1 */ __fallthrough; case STD_OP_LE: if (expr->pat.parse == pat_parse_int) snprintf(buffer, NB_LLMAX_STR+NB_LLMAX_STR+2, ":%lld", value); else snprintf(buffer, NB_LLMAX_STR+NB_LLMAX_STR+2, ":%lld.%lld", value >> 16, value & 0xffff); arg = buffer; break; } } } /* Add sample to the reference, and try to compile it fior each pattern * using this value. */ if (!pat_ref_add(ref, arg, NULL, err)) goto out_free_expr; args++; } return expr; out_free_expr: prune_acl_expr(expr); free(expr); out_free_smp: free(ckw); free(smp); out_return: return NULL; } /* Purge everything in the acl , then return . */ struct acl *prune_acl(struct acl *acl) { struct acl_expr *expr, *exprb; free(acl->name); list_for_each_entry_safe(expr, exprb, &acl->expr, list) { LIST_DELETE(&expr->list); prune_acl_expr(expr); free(expr); } return acl; } /* Walk the ACL tree, following nested acl() sample fetches, for no more than * max_recurse evaluations. Returns -1 if a recursive loop is detected, 0 if * the max_recurse was reached, otherwise the number of max_recurse left. */ static int parse_acl_recurse(struct acl *acl, struct acl_expr *expr, int max_recurse) { struct acl_term *term; struct acl_sample *sample; if (strcmp(expr->smp->fetch->kw, "acl") != 0) return max_recurse; if (--max_recurse <= 0) return 0; sample = (struct acl_sample *)expr->smp->arg_p->data.ptr; list_for_each_entry(term, &sample->suite.terms, list) { if (term->acl == acl) return -1; list_for_each_entry(expr, &term->acl->expr, list) { max_recurse = parse_acl_recurse(acl, expr, max_recurse); if (max_recurse <= 0) return max_recurse; } } return max_recurse; } /* Parse an ACL with the name starting at [0], and with a list of already * known ACLs in . If the ACL was not in the list, it will be added. * A pointer to that ACL is returned. If the ACL has an empty name, then it's * an anonymous one and it won't be merged with any other one. If is not * NULL, it will be filled with an appropriate error. This pointer must be * freeable or NULL. is the arg_list serving as a head for unresolved * dependencies. It may be NULL if such dependencies are not allowed. * * args syntax: */ struct acl *parse_acl(const char **args, struct list *known_acl, char **err, struct arg_list *al, const char *file, int line) { __label__ out_return, out_free_acl_expr, out_free_name; struct acl *cur_acl; struct acl_expr *acl_expr; char *name; const char *pos; if (**args && (pos = invalid_char(*args))) { memprintf(err, "invalid character in ACL name : '%c'", *pos); goto out_return; } acl_expr = parse_acl_expr(args + 1, err, al, file, line); if (!acl_expr) { /* parse_acl_expr will have filled here */ goto out_return; } /* Check for args beginning with an opening parenthesis just after the * subject, as this is almost certainly a typo. Right now we can only * emit a warning, so let's do so. */ if (!strchr(args[1], '(') && *args[2] == '(') ha_warning("parsing acl '%s' :\n" " matching '%s' for pattern '%s' is likely a mistake and probably\n" " not what you want. Maybe you need to remove the extraneous space before '('.\n" " If you are really sure this is not an error, please insert '--' between the\n" " match and the pattern to make this warning message disappear.\n", args[0], args[1], args[2]); if (*args[0]) cur_acl = find_acl_by_name(args[0], known_acl); else cur_acl = NULL; if (cur_acl) { int ret = parse_acl_recurse(cur_acl, acl_expr, ACL_MAX_RECURSE); if (ret <= 0) { if (ret < 0) memprintf(err, "have a recursive loop"); else memprintf(err, "too deep acl() tree"); goto out_free_acl_expr; } } else { name = strdup(args[0]); if (!name) { memprintf(err, "out of memory when parsing ACL"); goto out_free_acl_expr; } cur_acl = calloc(1, sizeof(*cur_acl)); if (cur_acl == NULL) { memprintf(err, "out of memory when parsing ACL"); goto out_free_name; } LIST_INIT(&cur_acl->expr); LIST_APPEND(known_acl, &cur_acl->list); cur_acl->name = name; } /* We want to know what features the ACL needs (typically HTTP parsing), * and where it may be used. If an ACL relies on multiple matches, it is * OK if at least one of them may match in the context where it is used. */ cur_acl->use |= acl_expr->smp->fetch->use; cur_acl->val |= acl_expr->smp->fetch->val; LIST_APPEND(&cur_acl->expr, &acl_expr->list); return cur_acl; out_free_name: free(name); out_free_acl_expr: prune_acl_expr(acl_expr); free(acl_expr); out_return: return NULL; } /* Some useful ACLs provided by default. Only those used are allocated. */ const struct { const char *name; const char *expr[4]; /* put enough for longest expression */ } default_acl_list[] = { { .name = "TRUE", .expr = {"always_true",""}}, { .name = "FALSE", .expr = {"always_false",""}}, { .name = "LOCALHOST", .expr = {"src","127.0.0.1/8","::1",""}}, { .name = "HTTP", .expr = {"req.proto_http",""}}, { .name = "HTTP_1.0", .expr = {"req.ver","1.0",""}}, { .name = "HTTP_1.1", .expr = {"req.ver","1.1",""}}, { .name = "HTTP_2.0", .expr = {"req.ver","2.0",""}}, { .name = "HTTP_3.0", .expr = {"req.ver","3.0",""}}, { .name = "METH_CONNECT", .expr = {"method","CONNECT",""}}, { .name = "METH_DELETE", .expr = {"method","DELETE",""}}, { .name = "METH_GET", .expr = {"method","GET","HEAD",""}}, { .name = "METH_HEAD", .expr = {"method","HEAD",""}}, { .name = "METH_OPTIONS", .expr = {"method","OPTIONS",""}}, { .name = "METH_POST", .expr = {"method","POST",""}}, { .name = "METH_PUT", .expr = {"method","PUT",""}}, { .name = "METH_TRACE", .expr = {"method","TRACE",""}}, { .name = "HTTP_URL_ABS", .expr = {"url_reg","^[^/:]*://",""}}, { .name = "HTTP_URL_SLASH", .expr = {"url_beg","/",""}}, { .name = "HTTP_URL_STAR", .expr = {"url","*",""}}, { .name = "HTTP_CONTENT", .expr = {"req.hdr_val(content-length)","gt","0",""}}, { .name = "RDP_COOKIE", .expr = {"req.rdp_cookie_cnt","gt","0",""}}, { .name = "REQ_CONTENT", .expr = {"req.len","gt","0",""}}, { .name = "WAIT_END", .expr = {"wait_end",""}}, { .name = NULL, .expr = {""}} }; /* Find a default ACL from the default_acl list, compile it and return it. * If the ACL is not found, NULL is returned. In theory, it cannot fail, * except when default ACLs are broken, in which case it will return NULL. * If is not NULL, the ACL will be queued at its tail. If is * not NULL, it will be filled with an error message if an error occurs. This * pointer must be freeable or NULL. is an arg_list serving as a list head * to report missing dependencies. It may be NULL if such dependencies are not * allowed. */ static struct acl *find_acl_default(const char *acl_name, struct list *known_acl, char **err, struct arg_list *al, const char *file, int line) { __label__ out_return, out_free_acl_expr, out_free_name; struct acl *cur_acl; struct acl_expr *acl_expr; char *name; int index; for (index = 0; default_acl_list[index].name != NULL; index++) { if (strcmp(acl_name, default_acl_list[index].name) == 0) break; } if (default_acl_list[index].name == NULL) { memprintf(err, "no such ACL : '%s'", acl_name); return NULL; } acl_expr = parse_acl_expr((const char **)default_acl_list[index].expr, err, al, file, line); if (!acl_expr) { /* parse_acl_expr must have filled err here */ goto out_return; } name = strdup(acl_name); if (!name) { memprintf(err, "out of memory when building default ACL '%s'", acl_name); goto out_free_acl_expr; } cur_acl = calloc(1, sizeof(*cur_acl)); if (cur_acl == NULL) { memprintf(err, "out of memory when building default ACL '%s'", acl_name); goto out_free_name; } cur_acl->name = name; cur_acl->use |= acl_expr->smp->fetch->use; cur_acl->val |= acl_expr->smp->fetch->val; LIST_INIT(&cur_acl->expr); LIST_APPEND(&cur_acl->expr, &acl_expr->list); if (known_acl) LIST_APPEND(known_acl, &cur_acl->list); return cur_acl; out_free_name: free(name); out_free_acl_expr: prune_acl_expr(acl_expr); free(acl_expr); out_return: return NULL; } /* Parse an ACL condition starting at [0], relying on a list of already * known ACLs passed in . The new condition is returned (or NULL in * case of low memory). Supports multiple conditions separated by "or". If * is not NULL, it will be filled with a pointer to an error message in * case of error, that the caller is responsible for freeing. The initial * location must either be freeable or NULL. The list serves as a list head * for unresolved dependencies. It may be NULL if such dependencies are not * allowed. */ struct acl_cond *parse_acl_cond(const char **args, struct list *known_acl, enum acl_cond_pol pol, char **err, struct arg_list *al, const char *file, int line) { __label__ out_return, out_free_suite, out_free_term; int arg, neg; const char *word; struct acl *cur_acl; struct acl_term *cur_term; struct acl_term_suite *cur_suite; struct acl_cond *cond; unsigned int suite_val; cond = calloc(1, sizeof(*cond)); if (cond == NULL) { memprintf(err, "out of memory when parsing condition"); goto out_return; } LIST_INIT(&cond->list); LIST_INIT(&cond->suites); cond->pol = pol; cond->val = 0; cur_suite = NULL; suite_val = ~0U; neg = 0; for (arg = 0; *args[arg]; arg++) { word = args[arg]; /* remove as many exclamation marks as we can */ while (*word == '!') { neg = !neg; word++; } /* an empty word is allowed because we cannot force the user to * always think about not leaving exclamation marks alone. */ if (!*word) continue; if (strcasecmp(word, "or") == 0 || strcmp(word, "||") == 0) { /* new term suite */ cond->val |= suite_val; suite_val = ~0U; cur_suite = NULL; neg = 0; continue; } if (strcmp(word, "{") == 0) { /* we may have a complete ACL expression between two braces, * find the last one. */ int arg_end = arg + 1; const char **args_new; while (*args[arg_end] && strcmp(args[arg_end], "}") != 0) arg_end++; if (!*args[arg_end]) { memprintf(err, "missing closing '}' in condition"); goto out_free_suite; } args_new = calloc(1, (arg_end - arg + 1) * sizeof(*args_new)); if (!args_new) { memprintf(err, "out of memory when parsing condition"); goto out_free_suite; } args_new[0] = ""; memcpy(args_new + 1, args + arg + 1, (arg_end - arg) * sizeof(*args_new)); args_new[arg_end - arg] = ""; cur_acl = parse_acl(args_new, known_acl, err, al, file, line); free(args_new); if (!cur_acl) { /* note that parse_acl() must have filled here */ goto out_free_suite; } arg = arg_end; } else { /* search for in the known ACL names. If we do not find * it, let's look for it in the default ACLs, and if found, add * it to the list of ACLs of this proxy. This makes it possible * to override them. */ cur_acl = find_acl_by_name(word, known_acl); if (cur_acl == NULL) { cur_acl = find_acl_default(word, known_acl, err, al, file, line); if (cur_acl == NULL) { /* note that find_acl_default() must have filled here */ goto out_free_suite; } } } cur_term = calloc(1, sizeof(*cur_term)); if (cur_term == NULL) { memprintf(err, "out of memory when parsing condition"); goto out_free_suite; } cur_term->acl = cur_acl; cur_term->neg = neg; /* Here it is a bit complex. The acl_term_suite is a conjunction * of many terms. It may only be used if all of its terms are * usable at the same time. So the suite's validity domain is an * AND between all ACL keywords' ones. But, the global condition * is valid if at least one term suite is OK. So it's an OR between * all of their validity domains. We could emit a warning as soon * as suite_val is null because it means that the last ACL is not * compatible with the previous ones. Let's remain simple for now. */ cond->use |= cur_acl->use; suite_val &= cur_acl->val; if (!cur_suite) { cur_suite = calloc(1, sizeof(*cur_suite)); if (cur_suite == NULL) { memprintf(err, "out of memory when parsing condition"); goto out_free_term; } LIST_INIT(&cur_suite->terms); LIST_APPEND(&cond->suites, &cur_suite->list); } LIST_APPEND(&cur_suite->terms, &cur_term->list); neg = 0; } cond->val |= suite_val; return cond; out_free_term: free(cur_term); out_free_suite: free_acl_cond(cond); out_return: return NULL; } /* Builds an ACL condition starting at the if/unless keyword. The complete * condition is returned. NULL is returned in case of error or if the first * word is neither "if" nor "unless". It automatically sets the file name and * the line number in the condition for better error reporting, and sets the * HTTP initialization requirements in the proxy. If is not NULL, it will * be filled with a pointer to an error message in case of error, that the * caller is responsible for freeing. The initial location must either be * freeable or NULL. */ struct acl_cond *build_acl_cond(const char *file, int line, struct list *known_acl, struct proxy *px, const char **args, char **err) { enum acl_cond_pol pol = ACL_COND_NONE; struct acl_cond *cond = NULL; if (err) *err = NULL; if (strcmp(*args, "if") == 0) { pol = ACL_COND_IF; args++; } else if (strcmp(*args, "unless") == 0) { pol = ACL_COND_UNLESS; args++; } else { memprintf(err, "conditions must start with either 'if' or 'unless'"); return NULL; } cond = parse_acl_cond(args, known_acl, pol, err, &px->conf.args, file, line); if (!cond) { /* note that parse_acl_cond must have filled here */ return NULL; } cond->file = file; cond->line = line; px->http_needed |= !!(cond->use & SMP_USE_HTTP_ANY); return cond; } /* Execute condition and return either ACL_TEST_FAIL, ACL_TEST_MISS or * ACL_TEST_PASS depending on the test results. ACL_TEST_MISS may only be * returned if does not contain SMP_OPT_FINAL, indicating that incomplete * data is being examined. The function automatically sets SMP_OPT_ITERATE. This * function only computes the condition, it does not apply the polarity required * by IF/UNLESS, it's up to the caller to do this using something like this : * * res = acl_pass(res); * if (res == ACL_TEST_MISS) * return 0; * if (cond->pol == ACL_COND_UNLESS) * res = !res; */ enum acl_test_res acl_exec_cond(struct acl_cond *cond, struct proxy *px, struct session *sess, struct stream *strm, unsigned int opt) { __label__ fetch_next; struct acl_term_suite *suite; struct acl_term *term; struct acl_expr *expr; struct acl *acl; struct sample smp; enum acl_test_res acl_res, suite_res, cond_res; /* ACLs are iterated over all values, so let's always set the flag to * indicate this to the fetch functions. */ opt |= SMP_OPT_ITERATE; /* We're doing a logical OR between conditions so we initialize to FAIL. * The MISS status is propagated down from the suites. */ cond_res = ACL_TEST_FAIL; list_for_each_entry(suite, &cond->suites, list) { /* Evaluate condition suite . We stop at the first term * which returns ACL_TEST_FAIL. The MISS status is still propagated * in case of uncertainty in the result. */ /* we're doing a logical AND between terms, so we must set the * initial value to PASS. */ suite_res = ACL_TEST_PASS; list_for_each_entry(term, &suite->terms, list) { acl = term->acl; /* FIXME: use cache ! * check acl->cache_idx for this. */ /* ACL result not cached. Let's scan all the expressions * and use the first one to match. */ acl_res = ACL_TEST_FAIL; list_for_each_entry(expr, &acl->expr, list) { /* we need to reset context and flags */ memset(&smp, 0, sizeof(smp)); fetch_next: if (!sample_process(px, sess, strm, opt, expr->smp, &smp)) { /* maybe we could not fetch because of missing data */ if (smp.flags & SMP_F_MAY_CHANGE && !(opt & SMP_OPT_FINAL)) acl_res |= ACL_TEST_MISS; continue; } acl_res |= pat2acl(pattern_exec_match(&expr->pat, &smp, 0)); /* * OK now acl_res holds the result of this expression * as one of ACL_TEST_FAIL, ACL_TEST_MISS or ACL_TEST_PASS. * * Then if (!MISS) we can cache the result, and put * (smp.flags & SMP_F_VOLATILE) in the cache flags. * * FIXME: implement cache. * */ /* we're ORing these terms, so a single PASS is enough */ if (acl_res == ACL_TEST_PASS) break; if (smp.flags & SMP_F_NOT_LAST) goto fetch_next; /* sometimes we know the fetched data is subject to change * later and give another chance for a new match (eg: request * size, time, ...) */ if (smp.flags & SMP_F_MAY_CHANGE && !(opt & SMP_OPT_FINAL)) acl_res |= ACL_TEST_MISS; } /* * Here we have the result of an ACL (cached or not). * ACLs are combined, negated or not, to form conditions. */ if (term->neg) acl_res = acl_neg(acl_res); suite_res &= acl_res; /* we're ANDing these terms, so a single FAIL or MISS is enough */ if (suite_res != ACL_TEST_PASS) break; } cond_res |= suite_res; /* we're ORing these terms, so a single PASS is enough */ if (cond_res == ACL_TEST_PASS) break; } return cond_res; } /* Returns a pointer to the first ACL conflicting with usage at place * which is one of the SMP_VAL_* bits indicating a check place, or NULL if * no conflict is found. Only full conflicts are detected (ACL is not usable). * Use the next function to check for useless keywords. */ const struct acl *acl_cond_conflicts(const struct acl_cond *cond, unsigned int where) { struct acl_term_suite *suite; struct acl_term *term; struct acl *acl; list_for_each_entry(suite, &cond->suites, list) { list_for_each_entry(term, &suite->terms, list) { acl = term->acl; if (!(acl->val & where)) return acl; } } return NULL; } /* Returns a pointer to the first ACL and its first keyword to conflict with * usage at place which is one of the SMP_VAL_* bits indicating a check * place. Returns true if a conflict is found, with and set (if non * null), or false if not conflict is found. The first useless keyword is * returned. */ int acl_cond_kw_conflicts(const struct acl_cond *cond, unsigned int where, struct acl const **acl, char const **kw) { struct acl_term_suite *suite; struct acl_term *term; struct acl_expr *expr; list_for_each_entry(suite, &cond->suites, list) { list_for_each_entry(term, &suite->terms, list) { list_for_each_entry(expr, &term->acl->expr, list) { if (!(expr->smp->fetch->val & where)) { if (acl) *acl = term->acl; if (kw) *kw = expr->kw; return 1; } } } } return 0; } /* * Find targets for userlist and groups in acl. Function returns the number * of errors or OK if everything is fine. It must be called only once sample * fetch arguments have been resolved (after smp_resolve_args()). */ int acl_find_targets(struct proxy *p) { struct acl *acl; struct acl_expr *expr; struct pattern_list *pattern; int cfgerr = 0; struct pattern_expr_list *pexp; list_for_each_entry(acl, &p->acl, list) { list_for_each_entry(expr, &acl->expr, list) { if (strcmp(expr->kw, "http_auth_group") == 0) { /* Note: the ARGT_USR argument may only have been resolved earlier * by smp_resolve_args(). */ if (expr->smp->arg_p->unresolved) { ha_alert("Internal bug in proxy %s: %sacl %s %s() makes use of unresolved userlist '%s'. Please report this.\n", p->id, *acl->name ? "" : "anonymous ", acl->name, expr->kw, expr->smp->arg_p->data.str.area); cfgerr++; continue; } if (LIST_ISEMPTY(&expr->pat.head)) { ha_alert("proxy %s: acl %s %s(): no groups specified.\n", p->id, acl->name, expr->kw); cfgerr++; continue; } /* For each pattern, check if the group exists. */ list_for_each_entry(pexp, &expr->pat.head, list) { if (LIST_ISEMPTY(&pexp->expr->patterns)) { ha_alert("proxy %s: acl %s %s(): no groups specified.\n", p->id, acl->name, expr->kw); cfgerr++; continue; } list_for_each_entry(pattern, &pexp->expr->patterns, list) { /* this keyword only has one argument */ if (!check_group(expr->smp->arg_p->data.usr, pattern->pat.ptr.str)) { ha_alert("proxy %s: acl %s %s(): invalid group '%s'.\n", p->id, acl->name, expr->kw, pattern->pat.ptr.str); cfgerr++; } } } } } } return cfgerr; } /* initializes ACLs by resolving the sample fetch names they rely upon. * Returns 0 on success, otherwise an error. */ int init_acl() { int err = 0; int index; const char *name; struct acl_kw_list *kwl; struct sample_fetch *smp; list_for_each_entry(kwl, &acl_keywords.list, list) { for (index = 0; kwl->kw[index].kw != NULL; index++) { name = kwl->kw[index].fetch_kw; if (!name) name = kwl->kw[index].kw; smp = find_sample_fetch(name, strlen(name)); if (!smp) { ha_alert("Critical internal error: ACL keyword '%s' relies on sample fetch '%s' which was not registered!\n", kwl->kw[index].kw, name); err++; continue; } kwl->kw[index].smp = smp; } } return err; } /* dump known ACL keywords on stdout */ void acl_dump_kwd(void) { struct acl_kw_list *kwl; const struct acl_keyword *kwp, *kw; const char *name; int index; for (kw = kwp = NULL;; kwp = kw) { list_for_each_entry(kwl, &acl_keywords.list, list) { for (index = 0; kwl->kw[index].kw != NULL; index++) { if (strordered(kwp ? kwp->kw : NULL, kwl->kw[index].kw, kw != kwp ? kw->kw : NULL)) kw = &kwl->kw[index]; } } if (kw == kwp) break; name = kw->fetch_kw; if (!name) name = kw->kw; printf("%s = %s -m %s\n", kw->kw, name, pat_match_names[kw->match_type]); } } /* Purge everything in the acl_cond , then free */ void free_acl_cond(struct acl_cond *cond) { struct acl_term_suite *suite, *suiteb; struct acl_term *term, *termb; if (!cond) return; list_for_each_entry_safe(suite, suiteb, &cond->suites, list) { list_for_each_entry_safe(term, termb, &suite->terms, list) { LIST_DELETE(&term->list); free(term); } LIST_DELETE(&suite->list); free(suite); } free(cond); } static int smp_fetch_acl(const struct arg *args, struct sample *smp, const char *kw, void *private) { struct acl_sample *acl_sample = (struct acl_sample *)args->data.ptr; enum acl_test_res ret; ret = acl_exec_cond(&acl_sample->cond, smp->px, smp->sess, smp->strm, smp->opt); if (ret == ACL_TEST_MISS) return 0; smp->data.u.sint = ret == ACL_TEST_PASS; smp->data.type = SMP_T_BOOL; return 1; } int smp_fetch_acl_parse(struct arg *args, char **err_msg) { struct acl_sample *acl_sample; char *name; int i; for (i = 0; args[i].type != ARGT_STOP; i++) ; acl_sample = calloc(1, sizeof(struct acl_sample) + sizeof(struct acl_term) * i); LIST_INIT(&acl_sample->suite.terms); LIST_INIT(&acl_sample->cond.suites); LIST_APPEND(&acl_sample->cond.suites, &acl_sample->suite.list); acl_sample->cond.val = ~0U; // the keyword is valid everywhere for now. args->data.ptr = acl_sample; for (i = 0; args[i].type != ARGT_STOP; i++) { name = args[i].data.str.area; if (name[0] == '!') { acl_sample->terms[i].neg = 1; name++; } if (!(acl_sample->terms[i].acl = find_acl_by_name(name, &curproxy->acl))) { memprintf(err_msg, "ACL '%s' not found", name); goto err; } acl_sample->cond.use |= acl_sample->terms[i].acl->use; acl_sample->cond.val &= acl_sample->terms[i].acl->val; LIST_APPEND(&acl_sample->suite.terms, &acl_sample->terms[i].list); } return 1; err: free(acl_sample); return 0; } /************************************************************************/ /* All supported sample and ACL keywords must be declared here. */ /************************************************************************/ /* Note: must not be declared as its list will be overwritten. * Please take care of keeping this list alphabetically sorted. */ static struct acl_kw_list acl_kws = {ILH, { { /* END */ }, }}; INITCALL1(STG_REGISTER, acl_register_keywords, &acl_kws); static struct sample_fetch_kw_list smp_kws = {ILH, { { "acl", smp_fetch_acl, ARG12(1,STR,STR,STR,STR,STR,STR,STR,STR,STR,STR,STR,STR), smp_fetch_acl_parse, SMP_T_BOOL, SMP_USE_CONST }, { /* END */ }, }}; INITCALL1(STG_REGISTER, sample_register_fetches, &smp_kws); /* * Local variables: * c-indent-level: 8 * c-basic-offset: 8 * End: */