X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=user_list.c;h=32a4309d4360fa73a8e7d0bbef622a7928001bb0;hp=64f211499fcf51416b9b2a080e1d1798e004c0b3;hb=62c0894fbb589dd45e69b7d9ef1fd152a9960d62;hpb=47fedd501291bf9b0ca2204e2af3d1617b6f18a8 diff --git a/user_list.c b/user_list.c index 64f21149..32a4309d 100644 --- a/user_list.c +++ b/user_list.c @@ -1,71 +1,122 @@ -/* - * Copyright (C) 2006-2007 Andre Noll - * - * 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. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. - */ +/* Copyright (C) 2006 Andre Noll , see file COPYING. */ + +/** \file user_list.c User handling for para_server. */ -/** \file user_list.c user handling for para_server */ +#include +#include #include "para.h" #include "error.h" +#include "crypt.h" #include "fd.h" #include "string.h" +#include "list.h" #include "user_list.h" -static struct list_head user_list; +static INITIALIZED_LIST_HEAD(user_list); /* - * lookup user in user list file. Fills in a user struct containing - * filename of the user's public key as well as the permissions of that user. - * Returns 1 on success, 0 if user does not exist and < 0 on errors. + * Wrapper for fgets(3). + * + * Unlike fgets(3), an integer value is returned. On success, this function + * returns 1. On errors, -E_FGETS is returned. A zero return value indicates an + * end of file condition. + */ +static int xfgets(char *line, int size, FILE *f) +{ +again: + if (fgets(line, size, f)) + return 1; + if (feof(f)) + return 0; + if (!ferror(f)) + return -E_FGETS; + if (errno != EINTR) { + PARA_ERROR_LOG("%s\n", strerror(errno)); + return -E_FGETS; + } + clearerr(f); + goto again; +} + +/** + * Remove all entries from the user list. + * + * This is called on shutdown and when the user list is reloaded because the + * server received SIGHUP. + */ +void user_list_deplete(void) +{ + struct user *u, *tmpu; + + list_for_each_entry_safe(u, tmpu, &user_list, node) { + list_del(&u->node); + free(u->name); + apc_free_pubkey(u->pubkey); + free(u); + } +} + +/** + * Initialize the list of users allowed to connect to para_server. + * + * \param user_list_file The file containing access information. + * + * If this function is called for the second time, the contents of the + * previous call are discarded, i.e. the user list is reloaded. + * + * This function either succeeds or calls exit(3). */ -static void populate_user_list(char *user_list_file) +void user_list_init(const char *user_list_file) { - FILE *file_ptr = NULL; - char *char_ptr; - char line[MAXLINE]; - /* keyword, user, key, perms */ - char w[MAXLINE], n[MAXLINE], k[MAXLINE], p[MAXLINE], tmp[4][MAXLINE]; - int num, ret; + int ret = -E_USERLIST; + FILE *file_ptr = fopen(user_list_file, "r"); + struct user *u; - file_ptr = fopen(user_list_file, "r"); - ret = -E_USERLIST; if (!file_ptr) - goto out; + goto err; + + user_list_deplete(); for (;;) { - struct user *u; - ret = para_fgets(line, MAXLINE, file_ptr); - if (ret < 0) - PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret)); + int num; + char line[255]; + /* keyword, name, key, perms */ + char w[255], n[255], k[255], p[255], tmp[4][255]; + struct asymmetric_key *pubkey; + + ret = xfgets(line, sizeof(line), file_ptr); if (ret <= 0) break; if (sscanf(line,"%200s %200s %200s %200s", w, n, k, p) < 3) continue; if (strcmp(w, "user")) continue; - PARA_DEBUG_LOG("found entry for %s\n", n); - u = para_malloc(sizeof(struct user)); + PARA_DEBUG_LOG("found entry for user %s\n", n); + ret = apc_get_pubkey(k, &pubkey); + if (ret < 0) { + PARA_NOTICE_LOG("skipping entry for user %s: %s\n", n, + para_strerror(-ret)); + continue; + } + /* + * In order to encrypt len := APC_CHALLENGE_SIZE + 2 * SESSION_KEY_LEN + * bytes using RSA_public_encrypt() with EME-OAEP padding mode, + * RSA_size(rsa) must be greater than len + 41. So ignore keys + * which are too short. For details see RSA_public_encrypt(3). + */ + if (ret <= APC_CHALLENGE_SIZE + 2 * SESSION_KEY_LEN + 41) { + PARA_WARNING_LOG("public key %s too short (%d)\n", + k, ret); + apc_free_pubkey(pubkey); + continue; + } + u = para_malloc(sizeof(*u)); u->name = para_strdup(n); - ret = get_rsa_key(k, &u->rsa, LOAD_PUBLIC_KEY); - if (ret < 0) - break; - char_ptr = p; - num = sscanf(char_ptr, "%200[A-Z_],%200[A-Z_],%200[A-Z_],%200[A-Z_]", + u->pubkey = pubkey; + u->perms = 0; + num = sscanf(p, "%200[A-Z_],%200[A-Z_],%200[A-Z_],%200[A-Z_]", tmp[0], tmp[1], tmp[2], tmp[3]); PARA_DEBUG_LOG("found %i perm entries\n", num); - u->perms = 0; while (num > 0) { num--; if (!strcmp(tmp[num], "VSS_READ")) @@ -82,52 +133,25 @@ static void populate_user_list(char *user_list_file) } para_list_add(&u->node, &user_list); } -out: - if (file_ptr) - fclose(file_ptr); + fclose(file_ptr); if (ret >= 0) return; - PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret)); +err: + PARA_EMERG_LOG("%s\n", para_strerror(-ret)); exit(EXIT_FAILURE); } /** - * initialize the list of users allowed to connecto to para_server + * Lookup a user in the user list. * - * \param user_list_file the file containing access information + * \param name The name of the user. * - * If this function is called a second time, the contents of the - * previous call are discarded. + * \return A pointer to the corresponding user struct if the user was found, \p + * NULL otherwise. */ -void init_user_list(char *user_list_file) +const struct user *user_list_lookup(const char *name) { - struct user *u, *tmp; - static int initialized; - - if (initialized) { - list_for_each_entry_safe(u, tmp, &user_list, node) { - list_del(&u->node); - free(u->name); - rsa_free(u->rsa); - free(u); - } - } else - INIT_LIST_HEAD(&user_list); - initialized = 1; - populate_user_list(user_list_file); -} - -/** - * lookup user in user_list. - * - * \param name of the user - * - * \return a pointer to the corresponding user struct if the user was found, - * \p NULL otherwise. - */ -struct user *lookup_user(const char *name) -{ - struct user *u; + const struct user *u; list_for_each_entry(u, &user_list, node) { if (strcmp(u->name, name)) continue;