cloud-agent/agent/azure.c
2018-05-08 09:48:08 +02:00

795 lines
19 KiB
C

/*
* Copyright (c) 2017 Reyk Floeter <reyk@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/queue.h>
#include <sys/stat.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
#include "main.h"
#include "http.h"
#include "xml.h"
static struct azure_config {
const char *az_apiversion;
unsigned int az_incarnation;
const char *az_privkey;
const char *az_pubkey;
const char *az_certs;
char *az_pubkeyval;
char *az_container;
} az_config = {
.az_apiversion = "2015-04-05",
.az_incarnation = 1,
.az_privkey = "/var/db/azure-transport.key",
.az_pubkey = "/var/db/azure-transport.pub",
.az_certs = "/var/db/azure-certificates.pem"
};
static struct httpget
*azure_request(struct system_config *, struct xml *,
const char *, const void *, size_t, struct httphead **);
static int azure_keys(struct system_config *);
static int azure_getpubkeys(struct system_config *);
static int azure_getovfenv(struct system_config *);
static int azure_versions(struct system_config *);
static int azure_goalstate(struct system_config *);
static int azure_certificates(struct system_config *);
static int azure_reporthealth(struct system_config *, const char *);
int
azure(struct system_config *sc)
{
int ret = -1;
/* Apply defaults */
free(sc->sc_username);
if ((sc->sc_username = strdup("azure-user")) == NULL) {
log_warnx("failed to set default user");
goto fail;
}
sc->sc_cdrom = "/dev/cd0c";
sc->sc_ovfenv = "/var/db/azure-ovf-env.xml";
sc->sc_priv = &az_config;
if (azure_getovfenv(sc) != 0) {
log_warnx("failed to get ovf-env.xml");
goto fail;
}
if (dhcp_getendpoint(sc) != 0) {
log_warnx("failed to get endpoint");
goto fail;
}
if (azure_versions(sc) != 0) {
log_warnx("failed to get endpoint versions");
goto fail;
}
if (azure_goalstate(sc) != 0) {
log_warnx("failed to get goalstate");
goto fail;
}
if (!sc->sc_dryrun) {
if (azure_keys(sc) != 0) {
log_warnx("failed to get transport keys");
goto fail;
}
if (azure_certificates(sc) != 0) {
log_warnx("failed to get certificates");
goto fail;
}
}
if (azure_reporthealth(sc, "Ready") != 0) {
log_warnx("failed to report health");
goto fail;
}
ret = 0;
fail:
free(az_config.az_container);
free(az_config.az_pubkeyval);
return (ret);
}
int
azure_keys(struct system_config *sc)
{
struct azure_config *az = sc->sc_priv;
int fd, i;
const char *k[4];
FILE *fp = NULL, *keyfp = NULL;
char buf[BUFSIZ];
char *keybuf = NULL;
size_t keybufsz;
k[0] = az->az_privkey;
k[1] = az->az_pubkey;
k[2] = az->az_certs;
k[3] = NULL;
if (access(az->az_privkey, R_OK) != 0 ||
access(az->az_pubkey, R_OK) != 0) {
/* Ugh, we must generate the files before writing the keys */
for (i = 0; k[i] != NULL; i++) {
if ((fd = open(k[i],
O_WRONLY|O_CREAT|O_TRUNC, 0600)) == -1)
return (-1);
close(fd);
}
fd = disable_output(sc, STDERR_FILENO);
/* Now generate the actual transport keys */
if (shell("openssl", "req",
"-x509", "-nodes", "-subj", "/CN=LinuxTransport",
"-days", "32768", "-newkey", "rsa:2048",
"-keyout", az->az_privkey,
"-out", az->az_pubkey,
NULL) != 0) {
log_debug("%s: failed to generate keys", __func__);
return (-1);
}
enable_output(sc, STDERR_FILENO, fd);
}
if ((fp = fopen(az->az_pubkey, "r")) == NULL) {
log_debug("%s: failed to read public key", __func__);
goto done;
}
if ((keyfp = open_memstream(&keybuf, &keybufsz)) == NULL) {
log_debug("%s: failed to open public key stream", __func__);
goto done;
}
/* We have to read the public key into a single base64 line */
while (fgets(buf, sizeof(buf), fp) != NULL) {
buf[strcspn(buf, "\r\n")] = '\0';
if (strcmp("-----BEGIN CERTIFICATE-----", buf) == 0 ||
strcmp("-----END CERTIFICATE-----", buf) == 0 ||
strlen(buf) < 1)
continue;
if (fputs(buf, keyfp) < 0) {
log_debug("%s: failed to write public key",
__func__);
goto done;
}
}
fclose(keyfp);
keyfp = NULL;
az->az_pubkeyval = keybuf;
done:
if (fp != NULL)
fclose(fp);
if (keyfp != NULL) {
fclose(keyfp);
free(keybuf);
}
return (0);
}
struct httpget *
azure_request(struct system_config *sc, struct xml *xml, const char *path,
const void *post, size_t postsz, struct httphead **head)
{
struct azure_config *az = sc->sc_priv;
struct httpget *g = NULL;
struct httphead **reqhead = NULL;
int i;
if (xml != NULL && xml_init(xml) != 0)
return (NULL);
for (i = 0; head != NULL && head[i] != NULL; i++)
;
if ((reqhead = calloc(i + 3, sizeof(struct httphead *))) == NULL) {
log_debug("%s: head", __func__);
goto fail;
}
for (i = 0; head != NULL && head[i] != NULL; i++)
reqhead[i] = head[i];
reqhead[i++] = &(struct httphead){ "x-ms-agent-name", "cloud-agent" };
reqhead[i++] = &(struct httphead){ "x-ms-version", az->az_apiversion };
reqhead[i++] = NULL;
g = http_get(&sc->sc_addr, 1,
sc->sc_endpoint, 80, path, post, postsz, reqhead);
if (g == NULL || g->code != 200) {
log_debug("%s: invalid response", __func__);
goto fail;
}
free(reqhead);
if (xml == NULL) {
if (log_getverbose() > 2)
fwrite(g->bodypart, g->bodypartsz, 1, stderr);
return (g);
}
if (g->bodypartsz < 1 ||
xml_parse_buffer(xml, g->bodypart, g->bodypartsz) != 0) {
log_debug("%s: xml", __func__);
goto fail;
}
if (log_getverbose() > 2)
xml_print(xml, TAILQ_FIRST(&xml->ox_root), 0, stderr);
return (g);
fail:
xml_free(xml);
if (reqhead != NULL)
free(reqhead);
if (g != NULL)
http_get_free(g);
return (NULL);
}
static int
azure_versions(struct system_config *sc)
{
struct azure_config *az = sc->sc_priv;
struct httpget *g;
struct xmlelem *xe, *xv;
int ret = -1;
struct xml xml;
if ((g = azure_request(sc, &xml, "/?comp=versions",
NULL, 0, NULL)) == NULL)
goto done;
if ((xe = xml_findl(&xml.ox_root,
"Versions", "Supported", NULL)) == NULL) {
log_debug("%s: unexpected xml document", __func__);
goto done;
}
TAILQ_FOREACH(xv, &xe->xe_head, xe_entry) {
if (strcmp("Version", xv->xe_tag) == 0 &&
strcmp(xv->xe_data, az->az_apiversion) == 0) {
/* success! */
log_debug("%s: API version %s", __func__, xv->xe_data);
ret = 0;
break;
}
}
done:
xml_free(&xml);
http_get_free(g);
return (ret);
}
static int
azure_goalstate(struct system_config *sc)
{
struct azure_config *az = sc->sc_priv;
struct httpget *g;
struct xmlelem *xe;
int ret = -1;
struct xml xml;
const char *errstr = NULL;
if ((g = azure_request(sc, &xml, "/machine/?comp=goalstate",
NULL, 0, NULL)) == NULL)
goto done;
if ((xe = xml_findl(&xml.ox_root,
"GoalState", "Version", NULL)) == NULL ||
strcmp(xe->xe_data, az->az_apiversion) != 0) {
log_debug("%s: unexpected API version", __func__);
goto done;
}
if ((xe = xml_findl(&xml.ox_root,
"GoalState", "Incarnation", NULL)) == NULL) {
log_debug("%s: unexpected incarnation", __func__);
goto done;
}
az->az_incarnation = strtonum(xe->xe_data, 1, INT_MAX, &errstr);
if (errstr != NULL) {
log_debug("%s: unexpected incarnation: %s", __func__, errstr);
goto done;
}
if ((xe = xml_findl(&xml.ox_root,
"GoalState", "Container", "ContainerId", NULL)) == NULL ||
(az->az_container =
get_word(xe->xe_data, xe->xe_datalen)) == NULL) {
log_debug("%s: unexpected container id", __func__);
goto done;
}
if ((xe = xml_findl(&xml.ox_root,
"GoalState", "Container", "RoleInstanceList",
"RoleInstance", "InstanceId", NULL)) == NULL ||
(sc->sc_instance =
get_word(xe->xe_data, xe->xe_datalen)) == NULL) {
log_debug("%s: unexpected instance id", __func__);
goto done;
}
log_debug("%s: container %s instance %s incarnation %d", __func__,
az->az_container, sc->sc_instance, az->az_incarnation);
ret = 0;
done:
xml_free(&xml);
http_get_free(g);
return (ret);
}
static int
azure_certificates(struct system_config *sc)
{
struct azure_config *az = sc->sc_priv;
struct httpget *g;
struct httphead *reqhead[3];
int ret = -1;
char *req = NULL;
char tmp1[32], tmp2[32];
struct xml xml;
struct xmlelem *xe, *data;
int fd;
memset(tmp1, 0, sizeof(tmp1));
memset(tmp2, 0, sizeof(tmp2));
reqhead[0] = &(struct httphead){ "x-ms-cipher-name", "DES_EDE3_CBC" };
reqhead[1] = &(struct httphead){
"x-ms-guest-agent-public-x509-cert", az->az_pubkeyval
};
reqhead[2] = NULL;
if (asprintf(&req, "/machine/%s/%s?comp=certificates&incarnation=%d",
az->az_container, sc->sc_instance, az->az_incarnation) == -1)
return (-1);
g = azure_request(sc, &xml, req, NULL, 0, reqhead);
http_get_free(g);
free(req);
req = NULL;
/* certificates are optional and only needed w/o password auth */
if (g == NULL)
return (0);
if ((xe = xml_findl(&xml.ox_root,
"CertificateFile", "Version", NULL)) == NULL ||
strcmp(xe->xe_data, az->az_apiversion) != 0) {
log_debug("%s: unexpected API version", __func__);
goto done;
}
if ((xe = xml_findl(&xml.ox_root,
"CertificateFile", "Format", NULL)) == NULL ||
strcmp(xe->xe_data, "Pkcs7BlobWithPfxContents") != 0) {
log_debug("%s: unexpected format", __func__);
goto done;
}
if ((data = xml_findl(&xml.ox_root,
"CertificateFile", "Data", NULL)) == NULL) {
log_debug("%s: no data", __func__);
goto done;
}
/* Write CMS blob to temporary file */
strlcpy(tmp1, "/tmp/azure-cms.XXXXXXXX", sizeof(tmp1));
if ((fd = mkstemp(tmp1)) == -1) {
log_debug("%s: failed to write data", __func__);
goto done;
}
dprintf(fd, "MIME-Version: 1.0\n"
"Content-Disposition: attachment; filename=\"smime.p7m\"\n"
"Content-Type: application/pkcs7-mime;"
" smime-type=enveloped-data; name=\"smime.p7m\"\n"
"Content-Transfer-Encoding: base64\n"
"\n%s",
data->xe_data);
close(fd);
strlcpy(tmp2, "/tmp/azure-pkcs12.XXXXXXXX", sizeof(tmp2));
if ((fd = mkstemp(tmp2)) == -1) {
log_debug("%s: failed to write data", __func__);
goto done;
}
close(fd);
fd = disable_output(sc, STDERR_FILENO);
#ifdef USE_OPENSSL
/*
* XXX Now comes the part that needs CMS which is only
* XXX present in OpenSSL but got removed from LibreSSL.
*/
log_debug("%s: running openssl cms", __func__);
if (shell("/usr/local/bin/eopenssl", "cms", /* )) */
#else
if (shell("/usr/local/bin/cms",
#endif
"-decrypt", "-inkey", az->az_privkey, "-des3",
"-in", tmp1, "-out", tmp2, NULL) != 0) {
enable_output(sc, STDERR_FILENO, fd);
log_debug("%s: failed to decrypt CMS blob", __func__);
goto done;
}
unlink(tmp1);
/* Decrypt PKCS12 blob (now with LibreSSL) */
if (shell("openssl", "pkcs12",
"-nodes", "-password", "pass:",
"-in", tmp2, "-out", az->az_certs, NULL) != 0) {
enable_output(sc, STDERR_FILENO, fd);
log_debug("%s: failed to decrypt PKCS12 blob", __func__);
goto done;
}
unlink(tmp2);
enable_output(sc, STDERR_FILENO, fd);
/*
* XXX the following could be done using libcrypto directly
*/
ret = azure_getpubkeys(sc);
done:
unlink(tmp1);
unlink(tmp2);
xml_free(&xml);
return (ret);
}
int
azure_getpubkeys(struct system_config *sc)
{
struct azure_config *az = sc->sc_priv;
char buf[BUFSIZ];
char *in = NULL, *out = NULL, *p, *v;
FILE *fp;
int ret = -1;
FILE *infp = NULL;
char *inbuf = NULL;
size_t inbufsz;
if ((fp = fopen(az->az_certs, "r")) == NULL) {
log_debug("%s: failed to read certificates", __func__);
goto done;
}
/* Read all certificates */
while (fgets(buf, sizeof(buf), fp) != NULL) {
buf[strcspn(buf, "\r\n")] = '\0';
if (strcmp("-----BEGIN CERTIFICATE-----", buf) == 0) {
if ((infp = open_memstream(&inbuf, &inbufsz)) == NULL) {
log_debug("%s: failed to write cert", __func__);
goto done;
}
} else if (infp == NULL)
continue;
fprintf(infp, "%s\n", buf);
if (strcmp("-----END CERTIFICATE-----", buf) == 0) {
fclose(infp);
infp = NULL;
/* Convert certificate into public key */
if (shellout(inbuf, &in,
"openssl", "x509", "-fingerprint", "-pubkey",
"-noout", NULL) != 0) {
log_debug("%s: could not get public key",
__func__);
goto done;
}
free(inbuf);
inbuf = NULL;
/* Convert public key into SSH key */
if (shellout(in, &out,
"ssh-keygen", "-i", "-m", "PKCS8",
"-f", "/dev/stdin", NULL) == -1) {
log_debug("%s: could not get ssh key",
__func__);
goto done;
}
/* Get public key fingerprint */
if ((p = strstr(in, "Fingerprint=")) == NULL) {
log_debug("%s: could not get fingerprint",
__func__);
goto done;
}
p[strcspn(p, "\r\n")] = '\0';
p += strlen("Fingerprint=");
/* Strip colons */
for (v = p + strlen(p); v != p; v--)
if (*v == ':')
memmove(v, v + 1, strlen(v));
if (agent_setpubkey(sc, out, p) > 0)
log_debug("%s: public key %s", __func__, p);
free(in);
in = NULL;
free(out);
out = NULL;
}
}
ret = 0;
done:
free(inbuf);
free(in);
free(out);
return (ret);
}
static int
azure_reporthealth(struct system_config *sc, const char *message)
{
struct azure_config *az = sc->sc_priv;
struct httpget *g = NULL;
struct httphead *httph, *reqhead[2];
const char *errstr = NULL;
size_t httphsz, i;
int ret = -1;
char *req;
int reqsz;
const char *state;
reqhead[0] = &(struct httphead){
"Content-Type", "text/xml; charset=utf-8"
};
reqhead[1] = NULL;
if (strcmp("Ready", message) == 0) {
state = "<State>Ready</State>";
} else {
state =
"<State>NotReady</State>\n"
"<Details>\n"
"<SubStatus>Provisioning</SubStatus>\n"
"<Description>Starting</Description>\n"
"</Details>";
}
reqsz = asprintf(&req,
"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
"<Health xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\">\n"
"<GoalStateIncarnation>%u</GoalStateIncarnation>\n"
"<Container>\n"
"<ContainerId>%s</ContainerId>\n"
"<RoleInstanceList>\n"
"<Role>\n"
"<InstanceId>%s</InstanceId>\n"
"<Health>%s</Health>\n"
"</Role>\n"
"</RoleInstanceList>\n"
"</Container>\n"
"</Health>\n",
az->az_incarnation,
az->az_container,
sc->sc_instance,
state);
if (reqsz == -1)
goto done;
if ((g = azure_request(sc, NULL, "/machine/?comp=health",
req, reqsz, reqhead)) == NULL)
goto done;
httph = http_head_parse(g->http, g->xfer, &httphsz);
for (i = 0; i < httphsz; i++) {
if (strcmp(httph[i].key,
"x-ms-latest-goal-state-incarnation-number") == 0) {
az->az_incarnation =
strtonum(httph[i].val, 1, INT_MAX, &errstr);
if (errstr != NULL) {
log_debug("%s: unexpected incarnation: %s",
__func__, errstr);
goto done;
}
ret = 0;
break;
}
}
if (ret != 0)
goto done;
log_debug("%s: %s, incarnation %u", __func__,
message, az->az_incarnation);
done:
http_get_free(g);
return (ret);
}
static int
azure_getovfenv(struct system_config *sc)
{
struct xml xml;
struct xmlelem *xp, *xe, *xk, *xv;
char *sshfp, *sshval, *str;
int mount = 0, ret = -1, fd = -1;
FILE *fp;
/* Silently try to mount the cdrom */
fd = disable_output(sc, STDERR_FILENO);
ret = shell("mount", "-r", sc->sc_cdrom, "/mnt", NULL);
enable_output(sc, STDERR_FILENO, fd);
fd = -1;
if (ret == 0) {
log_debug("%s: mounted %s", __func__, sc->sc_cdrom);
mount = 1;
}
ret = -1;
if (xml_init(&xml) != 0) {
log_debug("%s: xml", __func__);
goto done;
}
/* Fallback to and older ovf-env.xml file */
if (xml_parse(&xml, "/mnt/ovf-env.xml") == -1 &&
xml_parse(&xml, sc->sc_ovfenv) == -1)
goto done;
/* unmount if we mounted the cdrom before */
if (mount && shell("umount", "/mnt", NULL) == 0) {
log_debug("%s: unmounted %s", __func__, sc->sc_cdrom);
}
if ((xp = xml_findl(&xml.ox_root,
"Environment", "wa:ProvisioningSection",
"LinuxProvisioningConfigurationSet", NULL)) == NULL) {
log_debug("%s: could not find OVF structure", __func__);
goto done;
}
if ((xe = xml_findl(&xp->xe_head,
"SSH", "PublicKeys", NULL)) != NULL) {
/* Find all (optional) SSH keys */
TAILQ_FOREACH(xk, &xe->xe_head, xe_entry) {
if (strcasecmp(xk->xe_tag, "PublicKey") != 0)
continue;
sshfp = sshval = NULL;
if ((xv = xml_findl(&xk->xe_head,
"Fingerprint", NULL)) != NULL)
sshfp = get_word(xv->xe_data, xv->xe_datalen);
if ((xv = xml_findl(&xk->xe_head,
"Value", NULL)) != NULL)
sshval = get_line(xv->xe_data, xv->xe_datalen);
if (agent_addpubkey(sc, sshval, sshfp) != 0)
log_warnx("failed to add ssh pubkey");
free(sshfp);
free(sshval);
}
}
if ((xe = xml_findl(&xp->xe_head, "HostName", NULL)) != NULL) {
if ((sc->sc_hostname =
get_word(xe->xe_data, xe->xe_datalen)) == NULL) {
log_debug("%s: hostname failed", __func__);
goto done;
}
}
if ((xe = xml_findl(&xp->xe_head, "UserName", NULL)) != NULL) {
free(sc->sc_username);
if ((sc->sc_username =
get_word(xe->xe_data, xe->xe_datalen)) == NULL) {
log_debug("%s: username failed", __func__);
goto done;
}
}
if ((xe = xml_findl(&xp->xe_head, "UserPassword", NULL)) != NULL) {
if ((sc->sc_password = calloc(1, 128)) == NULL) {
log_debug("%s: password failed", __func__);
goto done;
}
/* Allow any non-NUL character as input */
str = strndup(xe->xe_data, xe->xe_datalen);
if (str == NULL ||
crypt_newhash(str, "bcrypt,a",
sc->sc_password, 128) != 0) {
log_debug("%s: password hashing failed", __func__);
free(sc->sc_password);
sc->sc_password = NULL;
free(str);
goto done;
}
free(str);
/* Replace unencrypted password with hash */
free(xe->xe_tag);
xe->xe_tag = strdup("UserPasswordHash");
/* Update element for xml_print() below */
explicit_bzero(xe->xe_data, xe->xe_datalen);
free(xe->xe_data);
xe->xe_data = strdup(sc->sc_password);
xe->xe_datalen = strlen(sc->sc_password);
} else if ((xe = xml_findl(&xp->xe_head,
"UserPasswordHash", NULL)) != NULL) {
if ((sc->sc_password =
get_word(xe->xe_data, xe->xe_datalen)) != NULL) {
log_debug("%s: password hash failed", __func__);
goto done;
}
}
if ((xe = xml_findl(&xp->xe_head, "CustomData", NULL)) != NULL) {
if ((sc->sc_userdata =
get_string(xe->xe_data, xe->xe_datalen)) == NULL) {
log_debug("%s: userdata failed", __func__);
goto done;
}
}
if ((fd = open(sc->sc_ovfenv, O_WRONLY|O_CREAT|O_TRUNC, 0600)) == -1 ||
(fp = fdopen(fd, "w")) == NULL) {
log_debug("%s: failed to open %s", __func__, sc->sc_ovfenv);
goto done;
}
xml_print(&xml, TAILQ_FIRST(&xml.ox_root), 0, fp);
fclose(fp);
log_debug("%s: wrote %s", __func__, sc->sc_ovfenv);
ret = 0;
done:
if (fd != -1)
close(fd);
xml_free(&xml);
return (ret);
}