src/server/config/acl.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2013 Olaf Wintermann. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "acl.h"

ACLFile* load_acl_file(char *file) {
    FILE *in = fopen(file, "r");
    if(in == NULL) {
        return NULL;
    }
    
    ACLFile *conf = malloc(sizeof(ACLFile));
    conf->parser.parse = acl_parse;
    conf->namedACLs = NULL;
    conf->uriACLs = NULL;
    conf->pathACLs = NULL;
    
    int r = cfg_parse_basic_file((ConfigParser*)conf, in);
    if(r != 0) {
        free_acl_file(conf);
        return NULL;
    }
     
    fclose(in);

    return conf;
}

void free_acl_file(ACLFile *conf) {
    ucx_mempool_destroy(conf->parser.mp->pool);
    free(conf);
}

int acl_parse(void *p, ConfigLine *begin, ConfigLine *end, sstr_t line) {
    ACLFile *aclf = p;
    UcxAllocator *mp = aclf->parser.mp;
    
    if(sstrprefix(line, sstr("ACL "))) {
        sstr_t param = sstrsubs(line, 4);
        UcxList *plist = cfg_param_list(param, mp); 
        ACLConfig *acl = OBJ_NEW(mp, ACLConfig);
        acl->type.ptr = NULL;
        acl->authparam = NULL;
        acl->entries = NULL;
        aclf->cur = acl;
        
        sstr_t type = cfg_param_get(plist, sstr("type"));
        sstr_t name = cfg_param_get(plist, sstr("name"));
        sstr_t path = cfg_param_get(plist, sstr("path"));
        sstr_t uri  = cfg_param_get(plist, sstr("uri"));
        
        if(name.ptr) {
            acl->id = name;
            aclf->namedACLs = ucx_list_append_a(mp, aclf->namedACLs, acl);
        } else if(path.ptr) {
            acl->id = path;
            aclf->pathACLs = ucx_list_append_a(mp, aclf->pathACLs, acl);
        } else if(uri.ptr) {
            acl->id = uri;
            aclf->uriACLs = ucx_list_append_a(mp, aclf->uriACLs, acl);
        }
        
        if(type.ptr) {
            acl->type = type;
        }
    } else if(sstrprefix(line, sstr("Authenticate "))) {
        sstr_t param = sstrsubs(line, 13);
        UcxList *plist = cfg_param_list(param, mp); 
        aclf->cur->authparam = plist;
    } else {
        if(parse_ace(aclf, line)) {
            // TODO: error
            return 1;
        }
    }
    
    return 0;
}

int parse_ace(ACLFile *f, sstr_t line) {
    ACLConfig *cur = f->cur;
    UcxAllocator *mp = f->parser.mp;
    
    ssize_t tkn = 0;
    sstr_t *tk = sstrsplit(line, sstr(":"), &tkn);
    if(!tk || tkn < 3) {
        fprintf(stderr, "parse_ace: to few tokens\n");
        return 1;
    }
    
    ACEConfig *ace = OBJ_NEW(mp, ACEConfig);
    memset(ace, 0, sizeof(ACEConfig));
    
    /*
     * first step: determine who is affected by this ace
     */
    int n = 0;
    sstr_t s = tk[0];
    
    if(!sstrcmp(s, sstr("user"))) {
        // next token is the user name
        s = tk[1];
        n++;
        ace->who = sstrdup_a(mp, s);
    } else if(!sstrcmp(s, sstr("group"))) {
        // next token is the group name
        s = tk[1];
        n++;
        ace->who = sstrdup_a(mp, s);
        ace->flags = ACLCFG_IDENTIFIER_GROUP;
    } else if(!sstrcmp(s, sstr("owner@"))) {
        ace->flags = ACLCFG_OWNER;
    } else if(!sstrcmp(s, sstr("group@"))) {
        ace->flags = ACLCFG_GROUP;
    } else if(!sstrcmp(s, sstr("everyone@"))) {
        ace->flags = ACLCFG_EVERYONE;
    } else {
        // you can specify only the user name in the ace
        ace->who = sstrdup_a(mp, s);
    }
    
    n++; //next token
    
    /*
     * get the access mask
     */
    
    if(n >= tkn) {
        // to few tokens
        fprintf(stderr, "parse_ace: ace incomplete\n");
        return 1;
    }
    s = tk[n];
    
    ssize_t maskn = 0;
    sstr_t *accessmask = sstrsplit(s, sstr(","), &maskn);
    for(int i=0;i<maskn;i++) {
        sstr_t access = accessmask[i];
        ace->access_mask = ace->access_mask | accstr2int(access);
    }
    free(accessmask);
    n++; // next token
    
    /*
     * get flags (optional) and ace type
     */
    
    int complete = 0;
    while(n < tkn) {
        s = tk[n];
        if(!sstrcmp(s, sstr("allow"))) {
            ace->type = ACLCFG_TYPE_ALLOWED;
            complete = 1;
            break;
        } else if(!sstrcmp(s, sstr("deny"))) {
            ace->type = ACLCFG_TYPE_DENIED;
            complete = 1;
            break;
        } else if(!sstrcmp(s, sstr("audit"))) {
            ace->type = ACLCFG_TYPE_AUDIT;
            complete = 1;
            break;
        } else if(!sstrcmp(s, sstr("alarm"))) {
            ace->type = ACLCFG_TYPE_ALARM;
            complete = 1;
            break;
        } else {
            // set flags
            ssize_t fln = 0;
            sstr_t *flags = sstrsplit(s, sstr(","), &fln);
            for(int i=0;i<fln;i++) {
                sstr_t flag = flags[i];
                if(!sstrcmp(flag, sstr("successful_access_flag"))) {
                    ace->flags = ace->flags | ACLCFG_SUCCESSFUL_ACCESS_FLAG;
                } else if(!sstrcmp(flag, sstr("failed_access_flag"))) {
                    ace->flags = ace->flags | ACLCFG_FAILED_ACCESS_ACE_FLAG;
                }
                // TODO: other flags
            }
            free(flags);
        }
        n++;
    }
    
    if(!complete) {
        fprintf(stderr, "parse_ace: ace incomplete\n");
        return 1;
    }
    
    cur->entries = ucx_list_append_a(mp, cur->entries, ace);
    
    return 0;
}

uint32_t accstr2int(sstr_t access) {
    uint32_t val = 0;
    if(!sstrcmp(access, sstr("read"))) {
        val = ACLCFG_READ;
    } else if(!sstrcmp(access, sstr("write"))) {
        val = ACLCFG_WRITE;
    } else if(!sstrcmp(access, sstr("read_data"))) {
        val = ACLCFG_READ_DATA;
    } else if(!sstrcmp(access, sstr("write_data"))) {
        val = ACLCFG_WRITE_DATA;
    } else if(!sstrcmp(access, sstr("append"))) {
        val = ACLCFG_APPEND;
    } else if(!sstrcmp(access, sstr("add"))) {
        val = ACLCFG_ADD_FILE;
    } else if(!sstrcmp(access, sstr("add_file"))) {
        val = ACLCFG_ADD_FILE;
    } else if(!sstrcmp(access, sstr("add_subdirectory"))) {
        val = ACLCFG_ADD_SUBDIRECTORY;
    } else if(!sstrcmp(access, sstr("read_xattr"))) {
        val = ACLCFG_READ_XATTR;
    } else if(!sstrcmp(access, sstr("write_xattr"))) {
        val = ACLCFG_WRITE_XATTR;
    } else if(!sstrcmp(access, sstr("execute"))) {
        val = ACLCFG_EXECUTE;
    } else if(!sstrcmp(access, sstr("delete_child"))) {
        val = ACLCFG_DELETE_CHILD;
    } else if(!sstrcmp(access, sstr("delete"))) {
        val = ACLCFG_DELETE;
    } else if(!sstrcmp(access, sstr("read_attributes"))) {
        val = ACLCFG_READ_ATTRIBUTES;
    } else if(!sstrcmp(access, sstr("write_attributes"))) {
        val = ACLCFG_WRITE_ATTRIBUTES;
    } else if(!sstrcmp(access, sstr("list"))) {
        val = ACLCFG_LIST;
    } else if(!sstrcmp(access, sstr("read_acl"))) {
        val = ACLCFG_READ_ACL;
    } else if(!sstrcmp(access, sstr("write_acl"))) {
        val = ACLCFG_WRITE_ACL;
    } else if(!sstrcmp(access, sstr("write_owner"))) {
        val = ACLCFG_WRITE_OWNER;
    } else if(!sstrcmp(access, sstr("synchronize"))) {
        val = ACLCFG_SYNCHRONIZE;
    }
    return val;
}