From a72b602cfabd360335a63e70b6cb1abf7e82f69a Mon Sep 17 00:00:00 2001 From: "Richard W.M. Jones" Date: Fri, 31 Oct 2014 11:02:33 +0000 Subject: [PATCH] launch: libvirt: Implement drive secrets (RHBZ#1159016). Implement the GUESTFS_ADD_DRIVE_OPTS_SECRET argument of guestfs_add_drive_opts. For libvirt we have to save the secret in libvirtd first, get a UUID, and then pass the UUID back through the domain XML. (cherry picked from commit 6d6644d52d8092dd4f4add859ebda06bea4b5b56) --- bootstrap | 1 + generator/actions.ml | 2 +- m4/.gitignore | 4 + src/launch-libvirt.c | 272 ++++++++++++++++++++++++++++++++++++++++++++++++++- 4 files changed, 275 insertions(+), 4 deletions(-) diff --git a/bootstrap b/bootstrap index b4afcdb..70789e3 100755 --- a/bootstrap +++ b/bootstrap @@ -41,6 +41,7 @@ accept4 areadlink areadlinkat arpa_inet +base64 byteswap c-ctype cloexec diff --git a/generator/actions.ml b/generator/actions.ml index ea715d0..4bc043b 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -1452,7 +1452,7 @@ specify the remote username you want. =item C For the C protocol only, this specifies the 'secret' to use when -connecting to the remote device. +connecting to the remote device. It must be base64 encoded. If not given, then a secret matching the given username will be looked up in the default keychain locations, or if no username is given, then no authentication diff --git a/m4/.gitignore b/m4/.gitignore index ed73ab3..b0f8d4b 100644 --- a/m4/.gitignore +++ b/m4/.gitignore @@ -5,6 +5,7 @@ /argmatch.m4 /arpa_inet_h.m4 /asm-underscore.m4 +/base64.m4 /btowc.m4 /byteswap.m4 /canonicalize-lgpl.m4 @@ -104,6 +105,7 @@ /inttypes-pri.m4 /ioctl.m4 /i-ring.m4 +/isatty.m4 /isc-posix.m4 /largefile.m4 /lchown.m4 @@ -166,6 +168,7 @@ /printf-posix.m4 /priv-set.m4 /progtest.m4 +/ptsname_r.m4 /putenv.m4 /quotearg.m4 /quote.m4 @@ -236,6 +239,7 @@ /thread.m4 /time_h.m4 /timespec.m4 +/ttyname_r.m4 /uintmax_t.m4 /ulonglong.m4 /ungetc.m4 diff --git a/src/launch-libvirt.c b/src/launch-libvirt.c index 026fd5a..5daa396 100644 --- a/src/launch-libvirt.c +++ b/src/launch-libvirt.c @@ -49,6 +49,7 @@ #endif #include "glthread/lock.h" +#include "base64.h" #include "guestfs.h" #include "guestfs-internal.h" @@ -96,6 +97,27 @@ xmlBufferDetach (xmlBufferPtr buf) } #endif +#ifdef HAVE_ATTRIBUTE_CLEANUP +#define CLEANUP_VIRSECRETFREE __attribute__((cleanup(cleanup_virSecretFree))) + +static void +cleanup_virSecretFree (void *ptr) +{ + virSecretPtr secret_obj = * (virSecretPtr *) ptr; + if (secret_obj) + virSecretFree (secret_obj); +} + +#else /* !HAVE_ATTRIBUTE_CLEANUP */ +#define CLEANUP_VIRSECRETFREE +#endif + +/* List used to store a mapping of secret to libvirt secret UUID. */ +struct secret { + char *secret; + char uuid[VIR_UUID_STRING_BUFLEN]; +}; + #define DOMAIN_NAME_LEN (8+16+1) /* "guestfs-" + random + \0 */ /* Per-handle data. */ @@ -108,6 +130,8 @@ struct backend_libvirt_data { char name[DOMAIN_NAME_LEN]; /* random name */ bool is_kvm; /* false = qemu, true = kvm (from capabilities)*/ unsigned long qemu_version; /* qemu version (from libvirt) */ + struct secret *secrets; /* list of secrets */ + size_t nr_secrets; char *uefi_code; /* UEFI (firmware) code and variables. */ char *uefi_vars; }; @@ -130,6 +154,9 @@ struct libvirt_xml_params { }; static int parse_capabilities (guestfs_h *g, const char *capabilities_xml, struct backend_libvirt_data *data); +static int add_secret (guestfs_h *g, virConnectPtr conn, struct backend_libvirt_data *data, const struct drive *drv); +static int find_secret (guestfs_h *g, const struct backend_libvirt_data *data, const struct drive *drv, const char **type, const char **uuid); +static int have_secret (guestfs_h *g, const struct backend_libvirt_data *data, const struct drive *drv); static xmlChar *construct_libvirt_xml (guestfs_h *g, const struct libvirt_xml_params *params); static void debug_appliance_permissions (guestfs_h *g); static void debug_socket_permissions (guestfs_h *g); @@ -224,6 +251,8 @@ launch_libvirt (guestfs_h *g, void *datav, const char *libvirt_uri) CLEANUP_FREE xmlChar *xml = NULL; CLEANUP_FREE char *appliance = NULL; struct sockaddr_un addr; + struct drive *drv; + size_t i; int r; uint32_t size; CLEANUP_FREE void *buf = NULL; @@ -456,6 +485,14 @@ launch_libvirt (guestfs_h *g, void *datav, const char *libvirt_uri) debug (g, "cannot find group 'qemu'"); } + /* Store any secrets in libvirtd, keeping a mapping from the secret + * to its UUID. + */ + ITER_DRIVES (g, i, drv) { + if (add_secret (g, conn, data, drv) == -1) + goto cleanup; + } + /* Construct the libvirt XML. */ if (g->verbose) guestfs___print_timestamped_message (g, "create libvirt XML"); @@ -1275,6 +1312,8 @@ construct_libvirt_xml_disk (guestfs_h *g, CLEANUP_FREE char *path = NULL; int is_host_device; CLEANUP_FREE char *format = NULL; + const char *type, *uuid; + int r; /* XXX We probably could support this if we thought about it some more. */ if (drv->iface) { @@ -1386,9 +1425,15 @@ construct_libvirt_xml_disk (guestfs_h *g, if (drv->src.username != NULL) { start_element ("auth") { attribute ("username", drv->src.username); - /* TODO: write the drive secret, after first storing it separately - * in libvirt - */ + r = find_secret (g, data, drv, &type, &uuid); + if (r == -1) + return -1; + if (r == 1) { + start_element ("secret") { + attribute ("type", type); + attribute ("uuid", uuid); + } end_element (); + } } end_element (); } break; @@ -1696,6 +1741,216 @@ construct_libvirt_xml_qemu_cmdline (guestfs_h *g, } static int +construct_libvirt_xml_secret (guestfs_h *g, + const struct backend_libvirt_data *data, + const struct drive *drv, + xmlTextWriterPtr xo) +{ + start_element ("secret") { + attribute ("ephemeral", "yes"); + attribute ("private", "yes"); + start_element ("description") { + string_format ("guestfs secret associated with %s %s", + data->name, drv->src.u.path); + } end_element (); + } end_element (); + + return 0; +} + +/* If drv->src.secret != NULL, store the secret in libvirt, and save + * the UUID so we can retrieve it later. Also there is some slight + * variation depending on the protocol. See + * http://libvirt.org/formatsecret.html + */ +static int +add_secret (guestfs_h *g, virConnectPtr conn, + struct backend_libvirt_data *data, const struct drive *drv) +{ + CLEANUP_XMLBUFFERFREE xmlBufferPtr xb = NULL; + xmlOutputBufferPtr ob; + CLEANUP_XMLFREETEXTWRITER xmlTextWriterPtr xo = NULL; + CLEANUP_FREE xmlChar *xml = NULL; + CLEANUP_VIRSECRETFREE virSecretPtr secret_obj = NULL; + const char *secret = drv->src.secret; + CLEANUP_FREE unsigned char *secret_raw = NULL; + size_t secret_raw_len = 0; + size_t i; + + if (secret == NULL) + return 0; + + /* If it was already stored, don't create another secret. */ + if (have_secret (g, data, drv)) + return 0; + + /* Create the XML for the secret. */ + xb = xmlBufferCreate (); + if (xb == NULL) { + perrorf (g, "xmlBufferCreate"); + return -1; + } + ob = xmlOutputBufferCreateBuffer (xb, NULL); + if (ob == NULL) { + perrorf (g, "xmlOutputBufferCreateBuffer"); + return -1; + } + xo = xmlNewTextWriter (ob); + if (xo == NULL) { + perrorf (g, "xmlNewTextWriter"); + return -1; + } + + if (xmlTextWriterSetIndent (xo, 1) == -1 || + xmlTextWriterSetIndentString (xo, BAD_CAST " ") == -1) { + perrorf (g, "could not set XML indent"); + return -1; + } + if (xmlTextWriterStartDocument (xo, NULL, NULL, NULL) == -1) { + perrorf (g, "xmlTextWriterStartDocument"); + return -1; + } + + if (construct_libvirt_xml_secret (g, data, drv, xo) == -1) + return -1; + + if (xmlTextWriterEndDocument (xo) == -1) { + perrorf (g, "xmlTextWriterEndDocument"); + return -1; + } + xml = xmlBufferDetach (xb); + if (xml == NULL) { + perrorf (g, "xmlBufferDetach"); + return -1; + } + + debug (g, "libvirt secret XML:\n%s", xml); + + /* Pass the XML to libvirt. */ + secret_obj = virSecretDefineXML (conn, (const char *) xml, 0); + if (secret_obj == NULL) { + libvirt_error (g, _("could not define libvirt secret")); + return -1; + } + + /* For Ceph, we have to base64 decode the secret. For others, we + * currently just pass the secret straight through. + */ + switch (drv->src.protocol) { + case drive_protocol_rbd: + if (!base64_decode_alloc (secret, strlen (secret), + (char **) &secret_raw, &secret_raw_len)) { + error (g, _("rbd protocol secret must be base64 encoded")); + return -1; + } + if (secret_raw == NULL) { + error (g, _("base64_decode_alloc: %m")); + return -1; + } + break; + case drive_protocol_file: + case drive_protocol_ftp: + case drive_protocol_ftps: + case drive_protocol_gluster: + case drive_protocol_http: + case drive_protocol_https: + case drive_protocol_iscsi: + case drive_protocol_nbd: + case drive_protocol_sheepdog: + case drive_protocol_ssh: + case drive_protocol_tftp: + secret_raw = (unsigned char *) safe_strdup (g, secret); + secret_raw_len = strlen (secret); + } + + /* Set the secret. */ + if (virSecretSetValue (secret_obj, secret_raw, secret_raw_len, 0) == -1) { + libvirt_error (g, _("could not set libvirt secret value")); + return -1; + } + + /* Get back the UUID and save it in the private data. */ + i = data->nr_secrets; + data->nr_secrets++; + data->secrets = + safe_realloc (g, data->secrets, sizeof (struct secret) * data->nr_secrets); + + data->secrets[i].secret = safe_strdup (g, secret); + + if (virSecretGetUUIDString (secret_obj, data->secrets[i].uuid) == -1) { + libvirt_error (g, _("could not get UUID from libvirt secret")); + return -1; + } + + return 0; +} + +static int +have_secret (guestfs_h *g, + const struct backend_libvirt_data *data, const struct drive *drv) +{ + size_t i; + + if (drv->src.secret == NULL) + return 0; + + for (i = 0; i < data->nr_secrets; ++i) { + if (STREQ (data->secrets[i].secret, drv->src.secret)) + return 1; + } + + return 0; +} + +/* Find a secret previously stored in libvirt. Returns the + * attributes. This function returns -1 + * if there was an error, 0 if there is no secret, and 1 if the + * secret was found and returned. + */ +static int +find_secret (guestfs_h *g, + const struct backend_libvirt_data *data, const struct drive *drv, + const char **type, const char **uuid) +{ + size_t i; + + if (drv->src.secret == NULL) + return 0; + + for (i = 0; i < data->nr_secrets; ++i) { + if (STREQ (data->secrets[i].secret, drv->src.secret)) { + *uuid = data->secrets[i].uuid; + + *type = "volume"; + + switch (drv->src.protocol) { + case drive_protocol_rbd: + *type = "ceph"; + break; + case drive_protocol_iscsi: + *type = "iscsi"; + break; + case drive_protocol_file: + case drive_protocol_ftp: + case drive_protocol_ftps: + case drive_protocol_gluster: + case drive_protocol_http: + case drive_protocol_https: + case drive_protocol_nbd: + case drive_protocol_sheepdog: + case drive_protocol_ssh: + case drive_protocol_tftp: + /* set to a default value above */ ; + } + + return 1; + } + } + + return 0; +} + +static int is_blk (const char *path) { struct stat statbuf; @@ -1717,6 +1972,7 @@ shutdown_libvirt (guestfs_h *g, void *datav, int check_for_errors) struct backend_libvirt_data *data = datav; virConnectPtr conn = data->conn; virDomainPtr dom = data->dom; + size_t i; int ret = 0; int flags; @@ -1751,6 +2007,12 @@ shutdown_libvirt (guestfs_h *g, void *datav, int check_for_errors) free (data->uefi_vars); data->uefi_vars = NULL; + for (i = 0; i < data->nr_secrets; ++i) + free (data->secrets[i].secret); + free (data->secrets); + data->secrets = NULL; + data->nr_secrets = 0; + return ret; } @@ -1855,6 +2117,10 @@ hot_add_drive_libvirt (guestfs_h *g, void *datav, return -1; } + /* If the drive has an associated secret, store it in libvirt. */ + if (add_secret (g, conn, data, drv) == -1) + return -1; + /* Create the XML for the new disk. */ xml = construct_libvirt_xml_hot_add_disk (g, data, drv, drv_index); if (xml == NULL) -- 1.8.3.1