Cleanup and improve `tinc fsck`.
authorKirill Isakov <is-kir@ya.ru>
Sun, 25 Jul 2021 07:23:27 +0000 (13:23 +0600)
committerKirill Isakov <is-kir@ya.ru>
Thu, 29 Jul 2021 13:22:26 +0000 (19:22 +0600)
- implement TODOs
- fix an invalid warning:
WARNING: public and private RSA keys do not match
- use the same configuration reading & parsing logic as in tincd
- read keys from all supported variables
- auto fix a few more broken key configurations
- fix a couple of rare memory leaks
- add warnings for host variables in server config and vice versa
- check duplicates for all configuration variables (not the first 50)
- check_conffile had a stack-buffer-underflow with going before the start of the line

src/fsck.c
src/openssl/rsa.c
src/rsa.h

index f10fe3c..7b18c19 100644 (file)
@@ -18,7 +18,6 @@
 */
 
 #include "system.h"
-
 #include "crypto.h"
 #include "ecdsa.h"
 #include "ecdsagen.h"
 #endif
 #include "tincctl.h"
 #include "utils.h"
+#include "xalloc.h"
+#include "keys.h"
+#include "conf.h"
+
+static const char *exe_name = NULL;
 
 static bool ask_fix(void) {
        if(force) {
@@ -60,13 +64,13 @@ again:
        goto again;
 }
 
-static void print_tinc_cmd(const char *argv0, const char *format, ...) {
+static void print_tinc_cmd(const char *format, ...) {
        if(confbasegiven) {
-               fprintf(stderr, "%s -c %s ", argv0, confbase);
+               fprintf(stderr, "%s -c %s ", exe_name, confbase);
        } else if(netname) {
-               fprintf(stderr, "%s -n %s ", argv0, netname);
+               fprintf(stderr, "%s -n %s ", exe_name, netname);
        } else {
-               fprintf(stderr, "%s ", argv0);
+               fprintf(stderr, "%s ", exe_name);
        }
 
        va_list va;
@@ -76,6 +80,33 @@ static void print_tinc_cmd(const char *argv0, const char *format, ...) {
        fputc('\n', stderr);
 }
 
+typedef enum {
+       KEY_RSA,
+       KEY_ED25519,
+       KEY_BOTH,
+} key_type_t;
+
+static void print_new_keys_cmd(key_type_t key_type, const char *message) {
+       fprintf(stderr, "%s\n\n", message);
+
+       switch(key_type) {
+       case KEY_RSA:
+               fprintf(stderr, "You can generate a new RSA keypair with:\n\n");
+               print_tinc_cmd("generate-rsa-keys");
+               break;
+
+       case KEY_ED25519:
+               fprintf(stderr, "You can generate a new Ed25519 keypair with:\n\n");
+               print_tinc_cmd("generate-ed25519-keys");
+               break;
+
+       case KEY_BOTH:
+               fprintf(stderr, "You can generate new keys with:\n\n");
+               print_tinc_cmd("generate-keys");
+               break;
+       }
+}
+
 static int strtailcmp(const char *str, const char *tail) {
        size_t slen = strlen(str);
        size_t tlen = strlen(tail);
@@ -87,454 +118,337 @@ static int strtailcmp(const char *str, const char *tail) {
        return memcmp(str + slen - tlen, tail, tlen);
 }
 
-static void check_conffile(const char *fname, bool server) {
-       (void)server;
+static void check_conffile(const char *nodename, bool server) {
+       splay_tree_t *config = NULL;
+       init_configuration(&config);
 
-       FILE *f = fopen(fname, "r");
+       bool read;
 
-       if(!f) {
-               fprintf(stderr, "ERROR: cannot read %s: %s\n", fname, strerror(errno));
-               return;
+       if(server) {
+               read = read_server_config(config);
+       } else {
+               read = read_host_config(config, nodename, true);
        }
 
-       char line[2048];
-       int lineno = 0;
-       bool skip = false;
-       const int maxvariables = 50;
-       int count[maxvariables];
-       memset(count, 0, sizeof(count));
-
-       while(fgets(line, sizeof(line), f)) {
-               if(skip) {
-                       if(!strncmp(line, "-----END", 8)) {
-                               skip = false;
-                       }
+       if(!read) {
+               exit_configuration(&config);
+               return;
+       }
 
-                       continue;
-               } else {
-                       if(!strncmp(line, "-----BEGIN", 10)) {
-                               skip = true;
-                               continue;
-                       }
-               }
+       size_t total_vars = 0;
 
-               int len;
-               char *variable, *value, *eol;
-               variable = value = line;
+       while(variables[total_vars].name) {
+               ++total_vars;
+       }
 
-               lineno++;
+       int count[total_vars];
+       memset(count, 0, sizeof(count));
 
-               eol = line + strlen(line);
+       for splay_each(config_t, conf, config) {
+               int var_type = 0;
 
-               while(strchr("\t \r\n", *--eol)) {
-                       *eol = '\0';
+               for(size_t i = 0; variables[i].name; ++i) {
+                       if(strcasecmp(variables[i].name, conf->variable) == 0) {
+                               count[i]++;
+                               var_type = variables[i].type;
+                       }
                }
 
-               if(!line[0] || line[0] == '#') {
+               if(var_type == 0) {
                        continue;
                }
 
-               len = strcspn(value, "\t =");
-               value += len;
-               value += strspn(value, "\t ");
-
-               if(*value == '=') {
-                       value++;
-                       value += strspn(value, "\t ");
+               if(var_type & VAR_OBSOLETE) {
+                       fprintf(stderr, "WARNING: obsolete variable %s in %s line %d\n",
+                               conf->variable, conf->file, conf->line);
                }
 
-               variable[len] = '\0';
-
-               bool found = false;
-
-               for(int i = 0; variables[i].name; i++) {
-                       if(strcasecmp(variables[i].name, variable)) {
-                               continue;
-                       }
-
-                       found = true;
-
-                       if(variables[i].type & VAR_OBSOLETE) {
-                               fprintf(stderr, "WARNING: obsolete variable %s in %s line %d\n", variable, fname, lineno);
-                       }
-
-                       if(i < maxvariables) {
-                               count[i]++;
-                       }
-               }
-
-               if(!found) {
-                       fprintf(stderr, "WARNING: unknown variable %s in %s line %d\n", variable, fname, lineno);
+               if(server && !(var_type & VAR_SERVER)) {
+                       fprintf(stderr, "WARNING: host variable %s found in server config %s line %d \n",
+                               conf->variable, conf->file, conf->line);
                }
 
-               if(!*value) {
-                       fprintf(stderr, "ERROR: no value for variable %s in %s line %d\n", variable, fname, lineno);
+               if(!server && !(var_type & VAR_HOST)) {
+                       fprintf(stderr, "WARNING: server variable %s found in host config %s line %d \n",
+                               conf->variable, conf->file, conf->line);
                }
        }
 
-       for(int i = 0; variables[i].name && i < maxvariables; i++) {
+       for(size_t i = 0; i < total_vars; ++i) {
                if(count[i] > 1 && !(variables[i].type & VAR_MULTIPLE)) {
-                       fprintf(stderr, "WARNING: multiple instances of variable %s in %s\n", variables[i].name, fname);
+                       fprintf(stderr, "WARNING: multiple instances of variable %s in %s\n",
+                               variables[i].name, nodename ? nodename : "tinc.conf");
                }
        }
 
-       if(ferror(f)) {
-               fprintf(stderr, "ERROR: while reading %s: %s\n", fname, strerror(errno));
-       }
-
-       fclose(f);
+       exit_configuration(&config);
 }
 
-int fsck(const char *argv0) {
 #ifdef HAVE_MINGW
-       int uid = 0;
+typedef int uid_t;
+
+static uid_t getuid() {
+       return 0;
+}
+
+static void check_key_file_mode(const char *fname) {
+       (void)fname;
+}
 #else
-       uid_t uid = getuid();
-#endif
+static void check_key_file_mode(const char *fname) {
+       const uid_t uid = getuid();
+       struct stat st;
 
-       // Check that tinc.conf is readable.
+       if(stat(fname, &st)) {
+               fprintf(stderr, "ERROR: could not stat private key file %s\n", fname);
+               return;
+       }
 
-       if(access(tinc_conf, R_OK)) {
-               fprintf(stderr, "ERROR: cannot read %s: %s\n", tinc_conf, strerror(errno));
+       if(st.st_mode & 077) {
+               fprintf(stderr, "WARNING: unsafe file permissions on %s.\n", fname);
 
-               if(errno == ENOENT) {
-                       fprintf(stderr, "No tinc configuration found. Create a new one with:\n\n");
-                       print_tinc_cmd(argv0, "init");
-               } else if(errno == EACCES) {
-                       if(uid != 0) {
-                               fprintf(stderr, "You are currently not running tinc as root. Use sudo?\n");
+               if(st.st_uid != uid) {
+                       fprintf(stderr, "You are not running %s as the same uid as %s.\n", exe_name, fname);
+               } else if(ask_fix()) {
+                       if(chmod(fname, st.st_mode & ~077u)) {
+                               fprintf(stderr, "ERROR: could not change permissions of %s: %s\n", fname, strerror(errno));
                        } else {
-                               fprintf(stderr, "Check the permissions of each component of the path %s.\n", tinc_conf);
+                               fprintf(stderr, "Fixed permissions of %s.\n", fname);
                        }
                }
-
-               return 1;
        }
+}
+#endif // HAVE_MINGW
 
-       char *name = get_my_name(true);
-
-       if(!name) {
-               fprintf(stderr, "ERROR: tinc cannot run without a valid Name.\n");
-               return 1;
+static char *read_node_name() {
+       if(access(tinc_conf, R_OK) == 0) {
+               return get_my_name(true);
        }
 
-       // Check for private keys.
-       // TODO: use RSAPrivateKeyFile and Ed25519PrivateKeyFile variables if present.
-
-       struct stat st;
-       char fname[PATH_MAX];
-       char dname[PATH_MAX];
-
-#ifndef DISABLE_LEGACY
-       rsa_t *rsa_priv = NULL;
-       snprintf(fname, sizeof(fname), "%s/rsa_key.priv", confbase);
+       fprintf(stderr, "ERROR: cannot read %s: %s\n", tinc_conf, strerror(errno));
 
-       if(stat(fname, &st)) {
-               if(errno != ENOENT) {
-                       // Something is seriously wrong here. If we can access the directory with tinc.conf in it, we should certainly be able to stat() an existing file.
-                       fprintf(stderr, "ERROR: cannot read %s: %s\n", fname, strerror(errno));
-                       fprintf(stderr, "Please correct this error.\n");
-                       free(name);
-                       return 1;
-               }
-       } else {
-               FILE *f = fopen(fname, "r");
-
-               if(!f) {
-                       fprintf(stderr, "ERROR: could not open %s: %s\n", fname, strerror(errno));
-                       free(name);
-                       return 1;
-               }
-
-               rsa_priv = rsa_read_pem_private_key(f);
-               fclose(f);
-
-               if(!rsa_priv) {
-                       fprintf(stderr, "ERROR: No key or unusable key found in %s.\n", fname);
-                       fprintf(stderr, "You can generate a new RSA key with:\n\n");
-                       print_tinc_cmd(argv0, "generate-rsa-keys");
-                       free(name);
-                       return 1;
-               }
-
-#ifndef HAVE_MINGW
+       if(errno == ENOENT) {
+               fprintf(stderr, "No tinc configuration found. Create a new one with:\n\n");
+               print_tinc_cmd("init");
+               return NULL;
+       }
 
-               if(st.st_mode & 077) {
-                       fprintf(stderr, "WARNING: unsafe file permissions on %s.\n", fname);
+       if(errno == EACCES) {
+               uid_t uid = getuid();
 
-                       if(st.st_uid != uid) {
-                               fprintf(stderr, "You are not running %s as the same uid as %s.\n", argv0, fname);
-                       } else if(ask_fix()) {
-                               if(chmod(fname, st.st_mode & ~077)) {
-                                       fprintf(stderr, "ERROR: could not change permissions of %s: %s\n", fname, strerror(errno));
-                               } else {
-                                       fprintf(stderr, "Fixed permissions of %s.\n", fname);
-                               }
-                       }
+               if(uid != 0) {
+                       fprintf(stderr, "You are currently not running tinc as root. Use sudo?\n");
+               } else {
+                       fprintf(stderr, "Check the permissions of each component of the path %s.\n", tinc_conf);
                }
-
-#endif
        }
 
-#endif
-
-       ecdsa_t *ecdsa_priv = NULL;
-       snprintf(fname, sizeof(fname), "%s/ed25519_key.priv", confbase);
-
-       if(stat(fname, &st)) {
-               if(errno != ENOENT) {
-                       // Something is seriously wrong here. If we can access the directory with tinc.conf in it, we should certainly be able to stat() an existing file.
-                       fprintf(stderr, "ERROR: cannot read %s: %s\n", fname, strerror(errno));
-                       fprintf(stderr, "Please correct this error.\n");
-                       free(name);
-                       return 1;
-               }
-       } else {
-               FILE *f = fopen(fname, "r");
+       return NULL;
+}
 
-               if(!f) {
-                       fprintf(stderr, "ERROR: could not open %s: %s\n", fname, strerror(errno));
-                       free(name);
-                       return 1;
-               }
+static bool build_host_conf_path(char *fname, const size_t len) {
+       char *name = get_my_name(true);
 
-               ecdsa_priv = ecdsa_read_pem_private_key(f);
-               fclose(f);
+       if(!name) {
+               fprintf(stderr, "ERROR: tinc cannot run without a valid Name.\n");
+               return false;
+       }
 
-               if(!ecdsa_priv) {
-                       fprintf(stderr, "ERROR: No key or unusable key found in %s.\n", fname);
-                       fprintf(stderr, "You can generate a new Ed25519 key with:\n\n");
-                       print_tinc_cmd(argv0, "generate-ed25519-keys");
-                       free(name);
-                       return 1;
-               }
+       snprintf(fname, len, "%s/hosts/%s", confbase, name);
+       free(name);
+       return true;
+}
 
-#ifndef HAVE_MINGW
+static bool ask_fix_ec_public_key(const char *fname, ecdsa_t *ec_priv) {
+       if(!ask_fix()) {
+               return true;
+       }
 
-               if(st.st_mode & 077) {
-                       fprintf(stderr, "WARNING: unsafe file permissions on %s.\n", fname);
+       if(!disable_old_keys(fname, "public Ed25519 key")) {
+               return false;
+       }
 
-                       if(st.st_uid != uid) {
-                               fprintf(stderr, "You are not running %s as the same uid as %s.\n", argv0, fname);
-                       } else if(ask_fix()) {
-                               if(chmod(fname, st.st_mode & ~077)) {
-                                       fprintf(stderr, "ERROR: could not change permissions of %s: %s\n", fname, strerror(errno));
-                               } else {
-                                       fprintf(stderr, "Fixed permissions of %s.\n", fname);
-                               }
-                       }
-               }
+       FILE *f = fopen(fname, "a");
 
-#endif
+       if(!f) {
+               fprintf(stderr, "ERROR: could not append to %s: %s\n", fname, strerror(errno));
+               return false;
        }
 
-#ifdef DISABLE_LEGACY
-
-       if(!ecdsa_priv) {
-               fprintf(stderr, "ERROR: No Ed25519 private key found.\n");
-#else
+       bool success = ecdsa_write_pem_public_key(ec_priv, f);
+       fclose(f);
 
-       if(!rsa_priv && !ecdsa_priv) {
-               fprintf(stderr, "ERROR: Neither RSA or Ed25519 private key found.\n");
-#endif
-               fprintf(stderr, "You can generate new keys with:\n\n");
-               print_tinc_cmd(argv0, "generate-keys");
-               free(name);
-               return 1;
+       if(success) {
+               fprintf(stderr, "Wrote Ed25519 public key to %s.\n", fname);
+       } else {
+               fprintf(stderr, "ERROR: could not write Ed25519 public key to %s.\n", fname);
        }
 
-       // Check for public keys.
-       // TODO: use RSAPublicKeyFile variable if present.
-
-       snprintf(fname, sizeof(fname), "%s/hosts/%s", confbase, name);
+       return success;
+}
 
-       free(name);
+#ifndef DISABLE_LEGACY
+static bool ask_fix_rsa_public_key(const char *fname, rsa_t *rsa_priv) {
+       if(!ask_fix()) {
+               return true;
+       }
 
-       if(access(fname, R_OK)) {
-               fprintf(stderr, "WARNING: cannot read %s\n", fname);
+       if(!disable_old_keys(fname, "public RSA key")) {
+               return false;
        }
 
-       FILE *f;
+       FILE *f = fopen(fname, "a");
 
-#ifndef DISABLE_LEGACY
-       rsa_t *rsa_pub = NULL;
+       if(!f) {
+               fprintf(stderr, "ERROR: could not append to %s: %s\n", fname, strerror(errno));
+               return false;
+       }
 
-       f = fopen(fname, "r");
+       bool success = rsa_write_pem_public_key(rsa_priv, f);
+       fclose(f);
 
-       if(f) {
-               rsa_pub = rsa_read_pem_public_key(f);
-               fclose(f);
+       if(success) {
+               fprintf(stderr, "Wrote RSA public key to %s.\n", fname);
+       } else {
+               fprintf(stderr, "ERROR: could not write RSA public key to %s.\n", fname);
        }
 
-       if(rsa_priv) {
-               if(!rsa_pub) {
-                       fprintf(stderr, "WARNING: No (usable) public RSA key found.\n");
+       return success;
+}
 
-                       if(ask_fix()) {
-                               FILE *f = fopen(fname, "a");
+static bool test_rsa_keypair(rsa_t *rsa_priv, rsa_t *rsa_pub, const char *host_file) {
+       size_t len = rsa_size(rsa_priv);
 
-                               if(f) {
-                                       if(rsa_write_pem_public_key(rsa_priv, f)) {
-                                               fprintf(stderr, "Wrote RSA public key to %s.\n", fname);
-                                       } else {
-                                               fprintf(stderr, "ERROR: could not write RSA public key to %s.\n", fname);
-                                       }
+       if(len != rsa_size(rsa_pub)) {
+               fprintf(stderr, "ERROR: public and private RSA key lengths do not match.\n");
+               return false;
+       }
 
-                                       fclose(f);
-                               } else {
-                                       fprintf(stderr, "ERROR: could not append to %s: %s\n", fname, strerror(errno));
-                               }
-                       }
-               } else {
-                       // TODO: suggest remedies
-                       size_t len = rsa_size(rsa_priv);
+       bool success = false;
+       uint8_t *plaintext = xmalloc(len);
+       uint8_t *encrypted = xzalloc(len);
+       uint8_t *decrypted = xzalloc(len);
 
-                       if(len != rsa_size(rsa_pub)) {
-                               fprintf(stderr, "ERROR: public and private RSA keys do not match.\n");
-                               rsa_free(rsa_pub);
-                               rsa_free(rsa_priv);
-                               free(ecdsa_priv);
-                               return 1;
-                       }
+       randomize(plaintext, len);
+       plaintext[0] &= 0x7f;
 
-                       char *buf1 = malloc(len);
-                       char *buf2 = malloc(len);
-                       char *buf3 = malloc(len);
-
-                       randomize(buf1, len);
-                       buf1[0] &= 0x7f;
-                       memset(buf2, 0, len);
-                       memset(buf3, 0, len);
-                       bool result = false;
-
-                       if(rsa_public_encrypt(rsa_pub, buf1, len, buf2)) {
-                               if(rsa_private_decrypt(rsa_priv, buf2, len, buf3)) {
-                                       if(memcmp(buf1, buf3, len)) {
-                                               result = true;
-                                       } else {
-                                               fprintf(stderr, "ERROR: public and private RSA keys do not match.\n");
-                                       }
-                               } else {
-                                       fprintf(stderr, "ERROR: private RSA key does not work.\n");
-                               }
+       if(rsa_public_encrypt(rsa_pub, plaintext, len, encrypted)) {
+               if(rsa_private_decrypt(rsa_priv, encrypted, len, decrypted)) {
+                       if(memcmp(plaintext, decrypted, len) == 0) {
+                               success = true;
                        } else {
-                               fprintf(stderr, "ERROR: public RSA key does not work.\n");
+                               fprintf(stderr, "ERROR: public and private RSA keys do not match.\n");
+                               success = ask_fix_rsa_public_key(host_file, rsa_priv);
                        }
+               } else {
+                       print_new_keys_cmd(KEY_RSA, "ERROR: private RSA key does not work.");
+               }
+       } else {
+               fprintf(stderr, "ERROR: public RSA key does not work.\n");
+               success = ask_fix_rsa_public_key(host_file, rsa_priv);
+       }
 
+       free(decrypted);
+       free(encrypted);
+       free(plaintext);
 
-                       rsa_free(rsa_pub);
-                       rsa_pub = NULL;
-
-                       free(buf3);
-                       free(buf2);
-                       free(buf1);
-
-                       if(!result) {
-                               rsa_free(rsa_priv);
-                               free(ecdsa_priv);
-                               return 1;
-                       }
-               }
+       return success;
+}
 
-               rsa_free(rsa_priv);
-               rsa_priv = NULL;
-       } else {
-               if(rsa_pub) {
-                       fprintf(stderr, "WARNING: A public RSA key was found but no private key is known.\n");
-                       rsa_free(rsa_pub);
-                       rsa_pub = NULL;
-               }
+static bool check_rsa_pubkey(rsa_t *rsa_priv, rsa_t *rsa_pub, const char *host_file) {
+       if(!rsa_pub) {
+               fprintf(stderr, "WARNING: No (usable) public RSA key found.\n");
+               return ask_fix_rsa_public_key(host_file, rsa_priv);
        }
 
-#endif
+       if(!rsa_priv) {
+               fprintf(stderr, "WARNING: A public RSA key was found but no private key is known.\n");
+               return true;
+       }
 
-       ecdsa_t *ecdsa_pub = NULL;
+       return test_rsa_keypair(rsa_priv, rsa_pub, host_file);
+}
+#endif // DISABLE_LEGACY
 
-       f = fopen(fname, "r");
+static bool test_ec_keypair(ecdsa_t *ec_priv, ecdsa_t *ec_pub, const char *host_file) {
+       // base64-encoded public key obtained from the PRIVATE key.
+       char *b64_priv_pub = ecdsa_get_base64_public_key(ec_priv);
 
-       if(f) {
-               ecdsa_pub = get_pubkey(f);
+       if(!b64_priv_pub) {
+               print_new_keys_cmd(KEY_ED25519, "ERROR: private Ed25519 key does not work.");
+               return false;
+       }
 
-               if(!ecdsa_pub) {
-                       rewind(f);
-                       ecdsa_pub = ecdsa_read_pem_public_key(f);
-               }
+       // base64-encoded public key obtained from the PUBLIC key.
+       char *b64_pub_pub = ecdsa_get_base64_public_key(ec_pub);
 
-               fclose(f);
+       if(!b64_pub_pub) {
+               fprintf(stderr, "ERROR: public Ed25519 key does not work.\n");
+               free(b64_priv_pub);
+               return ask_fix_ec_public_key(host_file, ec_priv);
        }
 
-       if(ecdsa_priv) {
-               if(!ecdsa_pub) {
-                       fprintf(stderr, "WARNING: No (usable) public Ed25519 key found.\n");
+       bool match = strcmp(b64_pub_pub, b64_priv_pub) == 0;
+       free(b64_pub_pub);
+       free(b64_priv_pub);
 
-                       if(ask_fix()) {
-                               FILE *f = fopen(fname, "a");
+       if(match) {
+               return true;
+       }
 
-                               if(f) {
-                                       if(ecdsa_write_pem_public_key(ecdsa_priv, f)) {
-                                               fprintf(stderr, "Wrote Ed25519 public key to %s.\n", fname);
-                                       } else {
-                                               fprintf(stderr, "ERROR: could not write Ed25519 public key to %s.\n", fname);
-                                       }
+       fprintf(stderr, "ERROR: public and private Ed25519 keys do not match.\n");
+       return ask_fix_ec_public_key(host_file, ec_priv);
+}
 
-                                       fclose(f);
-                               } else {
-                                       fprintf(stderr, "ERROR: could not append to %s: %s\n", fname, strerror(errno));
-                               }
-                       }
-               } else {
-                       // TODO: suggest remedies
-                       char *key1 = ecdsa_get_base64_public_key(ecdsa_pub);
+static bool check_ec_pubkey(ecdsa_t *ec_priv, ecdsa_t *ec_pub, const char *host_file) {
+       if(!ec_priv) {
+               if(ec_pub) {
+                       print_new_keys_cmd(KEY_ED25519, "WARNING: A public Ed25519 key was found but no private key is known.");
+               }
 
-                       free(ecdsa_pub);
-                       ecdsa_pub = NULL;
+               return true;
+       }
 
-                       if(!key1) {
-                               fprintf(stderr, "ERROR: public Ed25519 key does not work.\n");
-                               free(ecdsa_priv);
-                               return 1;
-                       }
+       if(ec_pub) {
+               return test_ec_keypair(ec_priv, ec_pub, host_file);
+       }
 
-                       char *key2 = ecdsa_get_base64_public_key(ecdsa_priv);
+       fprintf(stderr, "WARNING: No (usable) public Ed25519 key found.\n");
+       return ask_fix_ec_public_key(host_file, ec_priv);
+}
 
-                       if(!key2) {
-                               fprintf(stderr, "ERROR: private Ed25519 key does not work.\n");
-                               free(ecdsa_priv);
-                               free(key1);
-                               return 1;
-                       }
+static bool check_config_mode(const char *fname) {
+       if(access(fname, R_OK | X_OK) == 0) {
+               return true;
+       }
 
-                       int result = strcmp(key1, key2);
-                       free(key1);
-                       free(key2);
+       if(errno != EACCES) {
+               fprintf(stderr, "ERROR: cannot access %s: %s\n", fname, strerror(errno));
+               return false;
+       }
 
-                       if(result) {
-                               fprintf(stderr, "ERROR: public and private Ed25519 keys do not match.\n");
-                               free(ecdsa_priv);
-                               return 1;
-                       }
-               }
+       fprintf(stderr, "WARNING: cannot read and execute %s: %s\n", fname, strerror(errno));
 
-               free(ecdsa_priv);
-               ecdsa_priv = NULL;
-       } else {
-               if(ecdsa_pub) {
-                       fprintf(stderr, "WARNING: A public Ed25519 key was found but no private key is known.\n");
-                       free(ecdsa_pub);
-                       ecdsa_pub = NULL;
+       if(ask_fix()) {
+               if(chmod(fname, 0755)) {
+                       fprintf(stderr, "ERROR: cannot change permissions on %s: %s\n", fname, strerror(errno));
                }
        }
 
-       // Check whether scripts are executable
+       return true;
+}
 
-       struct dirent *ent;
+static bool check_script_confdir() {
+       char fname[PATH_MAX];
        DIR *dir = opendir(confbase);
 
        if(!dir) {
                fprintf(stderr, "ERROR: cannot read directory %s: %s\n", confbase, strerror(errno));
-               return 1;
+               return false;
        }
 
+       struct dirent *ent;
+
        while((ent = readdir(dir))) {
                if(strtailcmp(ent->d_name, "-up") && strtailcmp(ent->d_name, "-down")) {
                        continue;
@@ -563,33 +477,25 @@ int fsck(const char *argv0) {
                }
 
                snprintf(fname, sizeof(fname), "%s" SLASH "%s", confbase, ent->d_name);
-
-               if(access(fname, R_OK | X_OK)) {
-                       if(errno != EACCES) {
-                               fprintf(stderr, "ERROR: cannot access %s: %s\n", fname, strerror(errno));
-                               continue;
-                       }
-
-                       fprintf(stderr, "WARNING: cannot read and execute %s: %s\n", fname, strerror(errno));
-
-                       if(ask_fix()) {
-                               if(chmod(fname, 0755)) {
-                                       fprintf(stderr, "ERROR: cannot change permissions on %s: %s\n", fname, strerror(errno));
-                               }
-                       }
-               }
+               check_config_mode(fname);
        }
 
        closedir(dir);
 
-       snprintf(dname, sizeof(dname), "%s" SLASH "hosts", confbase);
-       dir = opendir(dname);
+       return true;
+}
+
+static bool check_script_hostdir(const char *host_dir) {
+       char fname[PATH_MAX];
+       DIR *dir = opendir(host_dir);
 
        if(!dir) {
-               fprintf(stderr, "ERROR: cannot read directory %s: %s\n", dname, strerror(errno));
-               return 1;
+               fprintf(stderr, "ERROR: cannot read directory %s: %s\n", host_dir, strerror(errno));
+               return false;
        }
 
+       struct dirent *ent;
+
        while((ent = readdir(dir))) {
                if(strtailcmp(ent->d_name, "-up") && strtailcmp(ent->d_name, "-down")) {
                        continue;
@@ -605,44 +511,165 @@ int fsck(const char *argv0) {
                *dash = 0;
 
                snprintf(fname, sizeof(fname), "%s" SLASH "hosts" SLASH "%s", confbase, ent->d_name);
+               check_config_mode(fname);
+       }
 
-               if(access(fname, R_OK | X_OK)) {
-                       if(errno != EACCES) {
-                               fprintf(stderr, "ERROR: cannot access %s: %s\n", fname, strerror(errno));
-                               continue;
-                       }
+       closedir(dir);
 
-                       fprintf(stderr, "WARNING: cannot read and execute %s: %s\n", fname, strerror(errno));
+       return true;
+}
 
-                       if(ask_fix()) {
-                               if(chmod(fname, 0755)) {
-                                       fprintf(stderr, "ERROR: cannot change permissions on %s: %s\n", fname, strerror(errno));
-                               }
-                       }
-               }
+#ifdef DISABLE_LEGACY
+static bool check_public_keys(splay_tree_t *config, const char *name, ecdsa_t *ec_priv) {
+#else
+static bool check_public_keys(splay_tree_t *config, const char *name, rsa_t *rsa_priv, ecdsa_t *ec_priv) {
+#endif
+       // Check public keys.
+       char host_file[PATH_MAX];
+
+       if(!build_host_conf_path(host_file, sizeof(host_file))) {
+               return false;
        }
 
-       closedir(dir);
+       if(access(host_file, R_OK)) {
+               fprintf(stderr, "WARNING: cannot read %s\n", host_file);
+       }
+
+       ecdsa_t *ec_pub = NULL;
+       read_ecdsa_public_key(&ec_pub, &config, name);
+
+       bool success = true;
+#ifndef DISABLE_LEGACY
+       rsa_t *rsa_pub = NULL;
+       read_rsa_public_key(&rsa_pub, config, name);
+
+       success = check_rsa_pubkey(rsa_priv, rsa_pub, host_file);
+       rsa_free(rsa_pub);
+#endif
+
+       if(!check_ec_pubkey(ec_priv, ec_pub, host_file)) {
+               success = false;
+       }
+
+       ecdsa_free(ec_pub);
+
+       return success;
+}
+
+static bool check_keypairs(splay_tree_t *config, const char *name) {
+       // Check private keys.
+       char *priv_keyfile = NULL;
+       ecdsa_t *ec_priv = read_ecdsa_private_key(config, &priv_keyfile);
+
+       if(priv_keyfile) {
+               check_key_file_mode(priv_keyfile);
+               free(priv_keyfile);
+               priv_keyfile = NULL;
+       }
+
+#ifdef DISABLE_LEGACY
+
+       if(!ec_priv) {
+               print_new_keys_cmd(KEY_ED25519, "ERROR: No Ed25519 private key found.");
+               return false;
+       }
+
+#else
+       rsa_t *rsa_priv = read_rsa_private_key(config, &priv_keyfile);
+
+       if(priv_keyfile) {
+               check_key_file_mode(priv_keyfile);
+               free(priv_keyfile);
+       }
+
+       if(!rsa_priv && !ec_priv) {
+               print_new_keys_cmd(KEY_BOTH, "ERROR: Neither RSA or Ed25519 private key found.");
+               return false;
+       }
+
+#endif
+
+#ifdef DISABLE_LEGACY
+       bool success = check_public_keys(config, name, ec_priv);
+#else
+       bool success = check_public_keys(config, name, rsa_priv, ec_priv);
+       rsa_free(rsa_priv);
+#endif
+       ecdsa_free(ec_priv);
 
-       // Check for obsolete / unsafe / unknown configuration variables.
+       return success;
+}
 
-       check_conffile(tinc_conf, true);
+static void check_config_variables(const char *host_dir) {
+       check_conffile(NULL, true);
 
-       dir = opendir(dname);
+       DIR *dir = opendir(host_dir);
 
        if(dir) {
-               while((ent = readdir(dir))) {
-                       if(!check_id(ent->d_name)) {
-                               continue;
+               for(struct dirent * ent; (ent = readdir(dir));) {
+                       if(check_id(ent->d_name)) {
+                               check_conffile(ent->d_name, false);
                        }
-
-                       snprintf(fname, sizeof(fname), "%s" SLASH "hosts" SLASH "%s", confbase, ent->d_name);
-                       check_conffile(fname, false);
                }
 
                closedir(dir);
        }
+}
+
+static bool check_scripts_and_configs() {
+       // Check whether scripts are executable.
+       if(!check_script_confdir()) {
+               return false;
+       }
 
-       return 0;
+       char host_dir[PATH_MAX];
+       snprintf(host_dir, sizeof(host_dir), "%s" SLASH "hosts", confbase);
+
+       if(!check_script_hostdir(host_dir)) {
+               return false;
+       }
+
+       // Check for obsolete / unsafe / unknown configuration variables (and print warnings).
+       check_config_variables(host_dir);
+
+       return true;
 }
 
+int fsck(const char *argv0) {
+       exe_name = argv0;
+
+       // Check that tinc.conf is readable and read our name if it is.
+       char *name = read_node_name();
+
+       if(!name) {
+               fprintf(stderr, "ERROR: tinc cannot run without a valid Name.\n");
+               exe_name = NULL;
+               return EXIT_FAILURE;
+       }
+
+       // Avoid touching global configuration here. Read the config files into
+       // a temporary configuration tree, then throw it away after fsck is done.
+       splay_tree_t *config = NULL;
+       init_configuration(&config);
+
+       // Read the server configuration file and append host configuration for our node.
+       bool success = read_server_config(config) &&
+                      read_host_config(config, name, true);
+
+       // Check both RSA and EC key pairs.
+       // We need working configuration to run this check.
+       if(success) {
+               success = check_keypairs(config, name);
+       }
+
+       // Check that scripts are executable and check the config for invalid variables.
+       // This check does not require working configuration, so run it always.
+       // This way, we can diagnose more issues on the first run.
+       success = success & check_scripts_and_configs();
+
+       exit_configuration(&config);
+       free(name);
+       exe_name = NULL;
+
+       return success ? EXIT_SUCCESS : EXIT_FAILURE;
+}
index 104b971..543262e 100644 (file)
@@ -102,7 +102,7 @@ rsa_t *rsa_read_pem_private_key(FILE *fp) {
        return rsa;
 }
 
-size_t rsa_size(rsa_t *rsa) {
+size_t rsa_size(const rsa_t *rsa) {
        return RSA_size(rsa);
 }
 
index a31ec24..9db9a8f 100644 (file)
--- a/src/rsa.h
+++ b/src/rsa.h
@@ -29,7 +29,7 @@ extern rsa_t *rsa_set_hex_public_key(char *n, char *e) __attribute__((__malloc__
 extern rsa_t *rsa_set_hex_private_key(char *n, char *e, char *d) __attribute__((__malloc__));
 extern rsa_t *rsa_read_pem_public_key(FILE *fp) __attribute__((__malloc__));
 extern rsa_t *rsa_read_pem_private_key(FILE *fp) __attribute__((__malloc__));
-extern size_t rsa_size(rsa_t *rsa);
+extern size_t rsa_size(const rsa_t *rsa);
 extern bool rsa_public_encrypt(rsa_t *rsa, void *in, size_t len, void *out) __attribute__((__warn_unused_result__));
 extern bool rsa_private_decrypt(rsa_t *rsa, void *in, size_t len, void *out) __attribute__((__warn_unused_result__));