Message ID | 153938334807.20740.14762115053745941956.stgit@djiang5-desk3.ch.intel.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | ndctl: add security support | expand |
On Fri, Oct 12, 2018 at 3:29 PM Dave Jiang <dave.jiang@intel.com> wrote: > > Adding a reference upcall helper for request-key in order to retrieve the > security passphrase from userspace to provide to the kernel. The reference > app uses keyutils API to respond to the upcall from the kernel and is > invoked by /sbin/request-key of the keyutils. > > Signed-off-by: Dave Jiang <dave.jiang@intel.com> > --- > Documentation/ndctl/Makefile.am | 3 - > Documentation/ndctl/nvdimm-upcall.txt | 33 +++++++ > Makefile.am | 5 + > contrib/nvdimm.conf | 1 > ndctl.spec.in | 2 > ndctl/Makefile.am | 4 + > ndctl/nvdimm-upcall.c | 154 +++++++++++++++++++++++++++++++++ > 7 files changed, 201 insertions(+), 1 deletion(-) > create mode 100644 Documentation/ndctl/nvdimm-upcall.txt > create mode 100644 contrib/nvdimm.conf > create mode 100644 ndctl/nvdimm-upcall.c > > diff --git a/Documentation/ndctl/Makefile.am b/Documentation/ndctl/Makefile.am > index 8c171ecb..f4e8b24c 100644 > --- a/Documentation/ndctl/Makefile.am > +++ b/Documentation/ndctl/Makefile.am > @@ -51,7 +51,8 @@ man1_MANS = \ > ndctl-update-security.1 \ > ndctl-disable-security.1 \ > ndctl-freeze-security.1 \ > - ndctl-sanitize.1 > + ndctl-sanitize.1 \ > + nvdimm-upcall.1 Any particular reason to not make this an ndctl command? It makes it discoverable with --list-cmds and the man page can be had via --help. I'd call it 'ndctl request-key'. > > CLEANFILES = $(man1_MANS) > > diff --git a/Documentation/ndctl/nvdimm-upcall.txt b/Documentation/ndctl/nvdimm-upcall.txt > new file mode 100644 > index 00000000..bbf52fd1 > --- /dev/null > +++ b/Documentation/ndctl/nvdimm-upcall.txt > @@ -0,0 +1,33 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +nvdimm-upcall(1) > +================ > + > +NAME > +---- > +nvdimm-upcall - upcall helper for keyutils > + > +SYNOPSIS > +-------- > +[verse] > +'nvdimm-upcall' [key_id] > + > +DESCRIPTION > +----------- > +nvdimm-upcall is called by request-key from keyutils and not meant to be used > +directly by the user. It expects to read from /etc/nvdimm.passwd to retrieve > +the description and passphrase for the NVDIMM key. > + > +The nvdimm.passwd is formatted as: > +<description id>:<passphrase with padded 0 to 32bytes> > +cdab-0a-07e0-feffffff:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa > + > +In order for this util to be called, /etc/request-key.conf must be appended > +with the following line: > +create logon nvdimm* * /usr/sbin/nvdimm-upcall %k > + > +include::../copyright.txt[] > + > +SEE ALSO > +-------- > +http://pmem.io/documents/NVDIMM_DSM_Interface-V1.7.pdf > diff --git a/Makefile.am b/Makefile.am > index e0c463a3..73aa2645 100644 > --- a/Makefile.am > +++ b/Makefile.am > @@ -42,6 +42,11 @@ bashcompletiondir = $(BASH_COMPLETION_DIR) > dist_bashcompletion_DATA = contrib/ndctl > endif > > +key_config_file = contrib/nvdimm.conf > +key_configdir = $(sysconfdir)/request-key.d/ > +key_config_DATA = $(key_config_file) > +EXTRA_DIST += $(key_config_file) > + > noinst_LIBRARIES = libccan.a > libccan_a_SOURCES = \ > ccan/str/str.h \ > diff --git a/contrib/nvdimm.conf b/contrib/nvdimm.conf > new file mode 100644 > index 00000000..e1f9a28b > --- /dev/null > +++ b/contrib/nvdimm.conf > @@ -0,0 +1 @@ > +create logon nvdimm:* * /usr/sbin/nvdimm-upcall %k > diff --git a/ndctl.spec.in b/ndctl.spec.in > index f57b4fd5..ef591615 100644 > --- a/ndctl.spec.in > +++ b/ndctl.spec.in > @@ -120,6 +120,8 @@ make check > %{bashcompdir}/ > %{_sysconfdir}/ndctl/monitor.conf > %{_unitdir}/ndctl-monitor.service > +%{_sbindir}/nvdimm-upcall > +%{_sysconfdir}/request-key.d/nvdimm.conf > > %files -n daxctl > %defattr(-,root,root) > diff --git a/ndctl/Makefile.am b/ndctl/Makefile.am > index 5b62251b..24ca98c7 100644 > --- a/ndctl/Makefile.am > +++ b/ndctl/Makefile.am > @@ -1,6 +1,7 @@ > include $(top_srcdir)/Makefile.am.in > > bin_PROGRAMS = ndctl > +sbin_PROGRAMS = nvdimm-upcall > > ndctl_SOURCES = ndctl.c \ > bus.c \ > @@ -52,3 +53,6 @@ EXTRA_DIST += $(monitor_config_file) > if ENABLE_SYSTEMD_UNITS > systemd_unit_DATA = ndctl-monitor.service > endif > + > +nvdimm_upcall_SOURCES = nvdimm-upcall.c > +nvdimm_upcall_LDADD = -lkeyutils > diff --git a/ndctl/nvdimm-upcall.c b/ndctl/nvdimm-upcall.c > new file mode 100644 > index 00000000..c8248359 > --- /dev/null > +++ b/ndctl/nvdimm-upcall.c > @@ -0,0 +1,154 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* Copyright(c) 2018 Intel Corporation. All rights reserved. */ > + > +/* > + * Used by /sbin/request-key for handling nvdimm upcall of key requests > + * for security DSMs. > + */ > + > + > +#include <stdio.h> > +#include <errno.h> > +#include <string.h> > +#include <stdlib.h> > +#include <unistd.h> > +#include <sys/stat.h> > +#include <sys/types.h> > +#include <sys/param.h> > +#include <keyutils.h> > +#include <syslog.h> > +#include <ctype.h> > + > +#define PASSPHRASE_SIZE 32 > +#define PASS_PATH "/etc/nvdimm.passwd" > + > +static FILE *fp; > + > +static int get_passphrase_from_id(const char *id, char *pass) > +{ > + ssize_t rc = 0; > + size_t size = 0, i; > + char *line = NULL; > + char *desc, *pass1; > + int found = 0, comment = 0; > + > + fp = fopen(PASS_PATH, "r+"); > + if (!fp) { > + syslog(LOG_ERR, "fopen: %s\n", strerror(errno)); > + return -errno; > + } > + > + while ((rc = getline(&line, &size, fp)) != -1) { > + /* skip comments */ > + for (i = 0; i < size; i++) { > + if (isspace(line[i])) > + continue; > + if (line[i] == '#') > + comment = 1; > + } > + > + if (comment) { > + comment = 0; > + continue; > + } > + > + desc = strtok(line, ":"); > + if (!desc) > + break; > + if (strcmp(desc, id) == 0) { > + found = 1; > + rc = 0; > + break; > + } > + } > + > + if (rc == 0 && found) { > + pass1 = strtok(NULL, ":"); > + if (!pass1) { > + rc = -EINVAL; > + goto out; > + } > + memset(pass, 0, PASSPHRASE_SIZE); > + memcpy(pass, pass1, MIN(strlen(pass1), PASSPHRASE_SIZE)); > + } else > + rc = -ENXIO; > + > +out: > + free(line); > + fclose(fp); > + return rc; > +} > + > +static char *get_key_desc(char *buf) > +{ > + char *tmp = &buf[0]; > + int count = 0; > + > + while (*tmp != '\0') { > + if (*tmp == ';') > + count++; > + if (count == 4) { > + tmp++; > + return tmp; > + } > + tmp++; > + } > + > + return NULL; > +} > + > +int main(int argc, const char **argv) Could you maybe add a comment or link to documentation about what the keyutils helper binary is supposed to do with its inputs? > +{ > + key_serial_t key; > + int rc; > + char *buf, *desc, *dimm_id; > + char pass[PASSPHRASE_SIZE]; > + > + if (argc < 2) { > + syslog(LOG_ERR, "Incorrect number of arguments\n"); > + return -EINVAL; > + } > + > + syslog(LOG_DEBUG, "key passed in: %s\n", argv[1]); > + key = strtol(argv[1], NULL, 10); > + if (key < 0) { > + syslog(LOG_ERR, "Invalid key format: %s\n", strerror(errno)); > + return -errno; > + } > + > + rc = keyctl_describe_alloc(key, &buf); > + if (rc < 0) { > + syslog(LOG_ERR, "keyctl_describe_alloc failed: %s\n", > + strerror(errno)); > + rc = -errno; > + goto out; > + } > + > + desc = get_key_desc(buf); > + if (!desc) { > + syslog(LOG_ERR, "Can't find key description\n"); > + rc = -EINVAL; > + goto out; > + } > + > + strtok_r(desc, ":", &dimm_id); > + rc = get_passphrase_from_id(dimm_id, pass); > + if (rc < 0) { > + syslog(LOG_ERR, "failed to retrieve passphrase\n"); > + goto out; > + } > + > + rc = keyctl_instantiate(key, pass, PASSPHRASE_SIZE, 0); > + if (rc < 0) { > + syslog(LOG_ERR, "keyctl_instantiate failed: %s\n", > + strerror(errno)); > + rc = -errno; > + goto out; > + } > + > + out: > + if (rc < 0) > + keyctl_negate(key, 1, KEY_REQKEY_DEFL_DEFAULT); > + > + return rc; > +} >
diff --git a/Documentation/ndctl/Makefile.am b/Documentation/ndctl/Makefile.am index 8c171ecb..f4e8b24c 100644 --- a/Documentation/ndctl/Makefile.am +++ b/Documentation/ndctl/Makefile.am @@ -51,7 +51,8 @@ man1_MANS = \ ndctl-update-security.1 \ ndctl-disable-security.1 \ ndctl-freeze-security.1 \ - ndctl-sanitize.1 + ndctl-sanitize.1 \ + nvdimm-upcall.1 CLEANFILES = $(man1_MANS) diff --git a/Documentation/ndctl/nvdimm-upcall.txt b/Documentation/ndctl/nvdimm-upcall.txt new file mode 100644 index 00000000..bbf52fd1 --- /dev/null +++ b/Documentation/ndctl/nvdimm-upcall.txt @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0 + +nvdimm-upcall(1) +================ + +NAME +---- +nvdimm-upcall - upcall helper for keyutils + +SYNOPSIS +-------- +[verse] +'nvdimm-upcall' [key_id] + +DESCRIPTION +----------- +nvdimm-upcall is called by request-key from keyutils and not meant to be used +directly by the user. It expects to read from /etc/nvdimm.passwd to retrieve +the description and passphrase for the NVDIMM key. + +The nvdimm.passwd is formatted as: +<description id>:<passphrase with padded 0 to 32bytes> +cdab-0a-07e0-feffffff:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa + +In order for this util to be called, /etc/request-key.conf must be appended +with the following line: +create logon nvdimm* * /usr/sbin/nvdimm-upcall %k + +include::../copyright.txt[] + +SEE ALSO +-------- +http://pmem.io/documents/NVDIMM_DSM_Interface-V1.7.pdf diff --git a/Makefile.am b/Makefile.am index e0c463a3..73aa2645 100644 --- a/Makefile.am +++ b/Makefile.am @@ -42,6 +42,11 @@ bashcompletiondir = $(BASH_COMPLETION_DIR) dist_bashcompletion_DATA = contrib/ndctl endif +key_config_file = contrib/nvdimm.conf +key_configdir = $(sysconfdir)/request-key.d/ +key_config_DATA = $(key_config_file) +EXTRA_DIST += $(key_config_file) + noinst_LIBRARIES = libccan.a libccan_a_SOURCES = \ ccan/str/str.h \ diff --git a/contrib/nvdimm.conf b/contrib/nvdimm.conf new file mode 100644 index 00000000..e1f9a28b --- /dev/null +++ b/contrib/nvdimm.conf @@ -0,0 +1 @@ +create logon nvdimm:* * /usr/sbin/nvdimm-upcall %k diff --git a/ndctl.spec.in b/ndctl.spec.in index f57b4fd5..ef591615 100644 --- a/ndctl.spec.in +++ b/ndctl.spec.in @@ -120,6 +120,8 @@ make check %{bashcompdir}/ %{_sysconfdir}/ndctl/monitor.conf %{_unitdir}/ndctl-monitor.service +%{_sbindir}/nvdimm-upcall +%{_sysconfdir}/request-key.d/nvdimm.conf %files -n daxctl %defattr(-,root,root) diff --git a/ndctl/Makefile.am b/ndctl/Makefile.am index 5b62251b..24ca98c7 100644 --- a/ndctl/Makefile.am +++ b/ndctl/Makefile.am @@ -1,6 +1,7 @@ include $(top_srcdir)/Makefile.am.in bin_PROGRAMS = ndctl +sbin_PROGRAMS = nvdimm-upcall ndctl_SOURCES = ndctl.c \ bus.c \ @@ -52,3 +53,6 @@ EXTRA_DIST += $(monitor_config_file) if ENABLE_SYSTEMD_UNITS systemd_unit_DATA = ndctl-monitor.service endif + +nvdimm_upcall_SOURCES = nvdimm-upcall.c +nvdimm_upcall_LDADD = -lkeyutils diff --git a/ndctl/nvdimm-upcall.c b/ndctl/nvdimm-upcall.c new file mode 100644 index 00000000..c8248359 --- /dev/null +++ b/ndctl/nvdimm-upcall.c @@ -0,0 +1,154 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright(c) 2018 Intel Corporation. All rights reserved. */ + +/* + * Used by /sbin/request-key for handling nvdimm upcall of key requests + * for security DSMs. + */ + + +#include <stdio.h> +#include <errno.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/param.h> +#include <keyutils.h> +#include <syslog.h> +#include <ctype.h> + +#define PASSPHRASE_SIZE 32 +#define PASS_PATH "/etc/nvdimm.passwd" + +static FILE *fp; + +static int get_passphrase_from_id(const char *id, char *pass) +{ + ssize_t rc = 0; + size_t size = 0, i; + char *line = NULL; + char *desc, *pass1; + int found = 0, comment = 0; + + fp = fopen(PASS_PATH, "r+"); + if (!fp) { + syslog(LOG_ERR, "fopen: %s\n", strerror(errno)); + return -errno; + } + + while ((rc = getline(&line, &size, fp)) != -1) { + /* skip comments */ + for (i = 0; i < size; i++) { + if (isspace(line[i])) + continue; + if (line[i] == '#') + comment = 1; + } + + if (comment) { + comment = 0; + continue; + } + + desc = strtok(line, ":"); + if (!desc) + break; + if (strcmp(desc, id) == 0) { + found = 1; + rc = 0; + break; + } + } + + if (rc == 0 && found) { + pass1 = strtok(NULL, ":"); + if (!pass1) { + rc = -EINVAL; + goto out; + } + memset(pass, 0, PASSPHRASE_SIZE); + memcpy(pass, pass1, MIN(strlen(pass1), PASSPHRASE_SIZE)); + } else + rc = -ENXIO; + +out: + free(line); + fclose(fp); + return rc; +} + +static char *get_key_desc(char *buf) +{ + char *tmp = &buf[0]; + int count = 0; + + while (*tmp != '\0') { + if (*tmp == ';') + count++; + if (count == 4) { + tmp++; + return tmp; + } + tmp++; + } + + return NULL; +} + +int main(int argc, const char **argv) +{ + key_serial_t key; + int rc; + char *buf, *desc, *dimm_id; + char pass[PASSPHRASE_SIZE]; + + if (argc < 2) { + syslog(LOG_ERR, "Incorrect number of arguments\n"); + return -EINVAL; + } + + syslog(LOG_DEBUG, "key passed in: %s\n", argv[1]); + key = strtol(argv[1], NULL, 10); + if (key < 0) { + syslog(LOG_ERR, "Invalid key format: %s\n", strerror(errno)); + return -errno; + } + + rc = keyctl_describe_alloc(key, &buf); + if (rc < 0) { + syslog(LOG_ERR, "keyctl_describe_alloc failed: %s\n", + strerror(errno)); + rc = -errno; + goto out; + } + + desc = get_key_desc(buf); + if (!desc) { + syslog(LOG_ERR, "Can't find key description\n"); + rc = -EINVAL; + goto out; + } + + strtok_r(desc, ":", &dimm_id); + rc = get_passphrase_from_id(dimm_id, pass); + if (rc < 0) { + syslog(LOG_ERR, "failed to retrieve passphrase\n"); + goto out; + } + + rc = keyctl_instantiate(key, pass, PASSPHRASE_SIZE, 0); + if (rc < 0) { + syslog(LOG_ERR, "keyctl_instantiate failed: %s\n", + strerror(errno)); + rc = -errno; + goto out; + } + + out: + if (rc < 0) + keyctl_negate(key, 1, KEY_REQKEY_DEFL_DEFAULT); + + return rc; +}
Adding a reference upcall helper for request-key in order to retrieve the security passphrase from userspace to provide to the kernel. The reference app uses keyutils API to respond to the upcall from the kernel and is invoked by /sbin/request-key of the keyutils. Signed-off-by: Dave Jiang <dave.jiang@intel.com> --- Documentation/ndctl/Makefile.am | 3 - Documentation/ndctl/nvdimm-upcall.txt | 33 +++++++ Makefile.am | 5 + contrib/nvdimm.conf | 1 ndctl.spec.in | 2 ndctl/Makefile.am | 4 + ndctl/nvdimm-upcall.c | 154 +++++++++++++++++++++++++++++++++ 7 files changed, 201 insertions(+), 1 deletion(-) create mode 100644 Documentation/ndctl/nvdimm-upcall.txt create mode 100644 contrib/nvdimm.conf create mode 100644 ndctl/nvdimm-upcall.c