On Thu, Nov 20, 2025 at 22:23:44 +0530, Arun Menon via Devel wrote: > A new configuration file called secrets.conf is introduced to > let the user configure the path to the secrets encryption key. > This key will be used to encrypt/decrypt the secrets in libvirt. > > By default the path is set to the runtime directory > /run/libvirt/secrets, and it is commented in the config file. > After parsing the file, the virtsecretd driver checks if an > encryption key is present in the path and is valid. > > By default, if no encryption key is present in the path, then > the service will by default use the encryption key stored in the > CREDENTIALS_DIRECTORY. > > Add logic to parse the encryption key file and store the key. > It also checks for the encrypt_data attribute in the config file. > The encryption and decryption logic will be added in the subsequent patches. > > Signed-off-by: Arun Menon <[email protected]> > --- > libvirt.spec.in | 3 + > po/POTFILES | 1 + > src/conf/meson.build | 1 + > src/conf/secret_config.c | 207 +++++++++++++++++++++++++ > src/conf/secret_config.h | 48 ++++++ > src/libvirt_private.syms | 2 + > src/secret/libvirt_secrets.aug | 40 +++++ > src/secret/meson.build | 18 +++ > src/secret/secrets.conf.in | 12 ++ > src/secret/test_libvirt_secrets.aug.in | 6 + > 10 files changed, 338 insertions(+) > create mode 100644 src/conf/secret_config.c > create mode 100644 src/conf/secret_config.h > create mode 100644 src/secret/libvirt_secrets.aug > create mode 100644 src/secret/secrets.conf.in > create mode 100644 src/secret/test_libvirt_secrets.aug.in
[...] > diff --git a/src/conf/secret_config.c b/src/conf/secret_config.c > new file mode 100644 > index 0000000000..a1c9b6bc2f > --- /dev/null > +++ b/src/conf/secret_config.c > @@ -0,0 +1,207 @@ > +/* > + * secret_config.c: secrets.conf config file handling > + * > + * Copyright (C) 2025 Red Hat, Inc. > + * > + * This library is free software; you can redistribute it and/or > + * modify it under the terms of the GNU Lesser General Public > + * License as published by the Free Software Foundation; either > + * version 2.1 of the License, or (at your option) any later version. > + * > + * This library 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 > + * Lesser General Public License for more details. > + * > + * You should have received a copy of the GNU Lesser General Public > + * License along with this library. If not, see > + * <http://www.gnu.org/licenses/>. > + */ For new files we usually use the SPDX header: /* * SPDX-License-Identifier: LGPL-2.1-or-later */ instead of the full blob above. > + > +#include <config.h> > +#include <fcntl.h> > +#include "configmake.h" > +#include "datatypes.h" > +#include "virlog.h" > +#include "virerror.h" > +#include "virfile.h" > +#include "virutil.h" > +#include "secret_config.h" > + > + > +#define VIR_FROM_THIS VIR_FROM_CONF > + > +VIR_LOG_INIT("secret.secret_config"); > + > +static virClass *virSecretDaemonConfigClass; > +static void virSecretDaemonConfigDispose(void *obj); > + > +static int > +virSecretConfigOnceInit(void) > +{ > + if (!VIR_CLASS_NEW(virSecretDaemonConfig, virClassForObject())) > + return -1; > + > + return 0; > +} > + > +VIR_ONCE_GLOBAL_INIT(virSecretConfig); > + > +int > +virSecretDaemonConfigFilePath(bool privileged, char **configfile) > +{ > + if (privileged) { > + *configfile = g_strdup(SYSCONFDIR "/libvirt/secrets.conf"); > + } else { > + g_autofree char *configdir = NULL; > + > + configdir = virGetUserConfigDirectory(); > + > + *configfile = g_strdup_printf("%s/secrets.conf", configdir); > + } > + > + return 0; > +} > + > +static int > +virSecretLoadDaemonConfig(virSecretDaemonConfig *cfg, > + const char *filename) > +{ > + g_autoptr(virConf) conf = NULL; > + > + if (access(filename, R_OK) == 0) { Use virFileExists instead of open-coding. > + conf = virConfReadFile(filename, 0); > + if (!conf) > + return -1; > + if (virConfGetValueInt(conf, "encrypt_data", &cfg->encrypt_data) < > 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Failed to get encrypt_data from %1$s"), > + filename); Not an internal error. VIR_ERR_CONF_SYNTAX Also encrypt_data really ought to be a bool based on usage. Here you'll have to convert it properly on parsing. > + return -1; > + } > + > + if (virConfGetValueString(conf, "secrets_encryption_key", > + &cfg->secretsEncryptionKeyPath) < 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Failed to get secrets_encryption_key from > %1$s"), > + filename); ditto > + return -1; > + } > + } > + return 0; > +} > + > +static bool getSecretsEncryptionKey(virSecretDaemonConfig *cfg, > + uint8_t **secrets_encryption_key, size_t > *secrets_encryption_keylen) This function doesn't follow the naming convention and coding style. > +{ > + int fd = -1; Declare this using VIR_AUTOCLOSE so that you don't have to deal with it in this whole file. > + struct stat st; > + > + if ((fd = open(cfg->secretsEncryptionKeyPath, O_RDONLY)) < 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, _("Cannot open secrets key > file '%1$s'"), > + cfg->secretsEncryptionKeyPath); > + return false; > + } I'd suggest you factor out the useful bits from 'qemuDomainMasterKeyReadFile' and then reuse it rather than reimplement this > + if (fstat(fd, &st) < 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, _("Cannot stat secrets key > file '%1$s'"), > + cfg->secretsEncryptionKeyPath); > + VIR_FORCE_CLOSE(fd); With the autoclose helper this won't be needed. > + return false; > + } > + *secrets_encryption_keylen = st.st_size; > + if (*secrets_encryption_keylen == 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, _("Secrets encryption key > file %1$s is empty"), > + cfg->secretsEncryptionKeyPath); > + VIR_FORCE_CLOSE(fd); > + return false; > + } > + *secrets_encryption_key = g_new0(uint8_t, *secrets_encryption_keylen); This allocates buffer based on the actual size, IMO yoiu should limit it to something more sensible. > + if (saferead(fd, &secrets_encryption_key, *secrets_encryption_keylen) != > *secrets_encryption_keylen) { > + virReportError(VIR_ERR_INTERNAL_ERROR, _("Cannot read secrets key > file '%1$s'"), > + cfg->secretsEncryptionKeyPath); > + VIR_FORCE_CLOSE(fd); > + return false; For functions using libvirt errors please stick to the '0' '-1' return value convntion. > + } > + VIR_FORCE_CLOSE(fd); > + if (*secrets_encryption_keylen != 32) { > + virReportError(VIR_ERR_INTERNAL_ERROR, _("Secrets encryption key > file %1$s must be 32 bytes"), > + cfg->secretsEncryptionKeyPath); > + return false; > + } > + return true; > +} > + > +virSecretDaemonConfig * > +virSecretDaemonConfigNew(bool privileged) > +{ > + g_autoptr(virSecretDaemonConfig) cfg = NULL; > + g_autofree char *configdir = NULL; > + g_autofree char *configfile = NULL; > + const char *credentials_directory; > + > + if (virSecretConfigInitialize() < 0) > + goto error; > + > + if (!(cfg = virObjectNew(virSecretDaemonConfigClass))) > + goto error; > + > + cfg->secretsEncryptionKeyPath = NULL; > + > + if (privileged) { > + configdir = g_strdup(SYSCONFDIR "/libvirt"); > + } else { > + g_autofree char *rundir = virGetUserRuntimeDirectory(); > + configdir = virGetUserConfigDirectory(); > + } > + configfile = g_strconcat(configdir, "/secrets.conf", NULL); This open-codes what the unused 'virSecretDaemonConfigFilePath' function does. Either use the function or delete it. > + if (virSecretLoadDaemonConfig(cfg, configfile) < 0) > + goto error; > + > + if (!(credentials_directory = getenv("CREDENTIALS_DIRECTORY"))) { > + credentials_directory = NULL; This is a pointless condition. If getenv("CREDENTIALS_DIRECTORY") returns NULL you set it to NULL. > + } > + > + if (cfg->secretsEncryptionKeyPath) { > + VIR_DEBUG("Secrets encryption key path: %s", > cfg->secretsEncryptionKeyPath); > + } else if (credentials_directory) { > + VIR_DEBUG("Using credentials directory from environment: %s", > + credentials_directory); > + cfg->secretsEncryptionKeyPath = > g_strdup_printf("%s/secrets-encryption-key", > + > credentials_directory); > + } else { > + VIR_DEBUG("No secrets encryption key found in credentials > directory"); > + cfg->secretsEncryptionKeyPath = NULL; > + } This logic is a bit convoluted. I suggest you do an unconditional log of the actual path after you determine whic one to use: if (!cfg->secretsEncryptionKeyPath && credentials_directory) { VIR_DEBUG("Using credentials directory from environment: %s", credentials_directory); cfg->secretsEncryptionKeyPath = g_strdup_printf("%s/secrets-encryption-key", credentials_directory); } VIR_DEBUG("Secrets encryption key path: %s", NULLSTR(cfg->secretsEncryptionKeyPath)); > + if (cfg->secretsEncryptionKeyPath && > access(cfg->secretsEncryptionKeyPath, R_OK) == 0) { > + if (!getSecretsEncryptionKey(cfg, &cfg->secrets_encryption_key, > &cfg->secretsKeyLen)) { > + VIR_DEBUG("Failed to get secrets encryption key from path: %s", > + cfg->secretsEncryptionKeyPath); > + goto error; You must properly report the error if you are to bail from daemon startup. Here !getSecretsEncryptionKey sets the value but it doesn't seem so because you do a pointless DEBUG (the error was already reported) > + } > + } > + > + if (cfg->encrypt_data != 1) { > + cfg->encrypt_data = (cfg->secretsKeyLen == 32) ? 1 : 0; So you set this to 1 even when the user set it to 0? Also 'encrypt_data' really ought to be a bool in the config struct. If users set this to 0 explicitly you shouldn't try to re-infer it. Here you also duplicate a magic constant used to limit the size so if anyone ever changes it in the other place only this will stop to work. If you want to automatically set this you'll also need to remember (possibly in another bool) if the explicit config option was seen or not. > + } else if (cfg->encrypt_data == 1) { > + if (!cfg->secretsEncryptionKeyPath) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("secretsEncryptionKeyPath must be set if > encrypt_data is 1 in %1$s"), > + configfile); This isn't an internal error, it's user's wrong config. Also make it a standalone check rather than an else branch. > + goto error; > + } > + } > + return g_steal_pointer(&cfg); > + error: > + virSecretDaemonConfigDispose(cfg); cfg is declared as autoptr so this is not needed as it ought to be called automatically. This also means that the whole 'error' label can be removed and 'NULL returned directly. > + return NULL; > +} > + > +static void > +virSecretDaemonConfigDispose(void *obj) > +{ > + virSecretDaemonConfig *cfg = obj; > + > + g_free(cfg->secrets_encryption_key); Use the function to securely clear it first, before freeing it here. > + g_free(cfg->secretsEncryptionKeyPath); > +} > diff --git a/src/conf/secret_config.h b/src/conf/secret_config.h > new file mode 100644 > index 0000000000..638b7c49a4 > --- /dev/null > +++ b/src/conf/secret_config.h > @@ -0,0 +1,48 @@ > +/* > + * secret_config.h: secrets.conf config file handling > + * > + * Copyright (C) 2025 Red Hat, Inc. > + * > + * This library is free software; you can redistribute it and/or > + * modify it under the terms of the GNU Lesser General Public > + * License as published by the Free Software Foundation; either > + * version 2.1 of the License, or (at your option) any later version. > + * > + * This library 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 > + * Lesser General Public License for more details. > + * > + * You should have received a copy of the GNU Lesser General Public > + * License along with this library. If not, see > + * <http://www.gnu.org/licenses/>. > + */ > + > +#pragma once > + > +#include "internal.h" > +#include "virinhibitor.h" > +#include "secret_event.h" > + > +typedef struct _virSecretDaemonConfig virSecretDaemonConfig; > +struct _virSecretDaemonConfig { > + virObject parent; > + /* secrets encryption key path from secrets.conf file */ > + char *secretsEncryptionKeyPath; > + > + unsigned char* secrets_encryption_key; unsigned char *sec... > + size_t secretsKeyLen; > + > + /* Indicates if the newly written secrets are encrypted or not. > + * 0 if not encrypted and 1 if encrypted. > + */ > + int encrypt_data; This ought to be either a 'bool' or one of the tristates. Alternatively two bools. > +}; > + > +G_DEFINE_AUTOPTR_CLEANUP_FUNC(virSecretDaemonConfig, virObjectUnref); > + > +int virSecretDaemonConfigFilePath(bool privileged, char **configfile); > +virSecretDaemonConfig *virSecretDaemonConfigNew(bool privileged); > +int virSecretDaemonConfigLoadFile(virSecretDaemonConfig *data, > + const char *filename, > + bool allow_missing); > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
