version 1.55, 2003/08/13 08:46:31 |
version 1.56, 2003/08/28 12:54:34 |
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#include <openssl/bn.h> |
#include <openssl/bn.h> |
#include <openssl/md5.h> |
#include <openssl/md5.h> |
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#ifdef KRB5 |
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#include <krb5.h> |
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#endif |
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#include "ssh.h" |
#include "ssh.h" |
#include "ssh1.h" |
#include "ssh1.h" |
#include "xmalloc.h" |
#include "xmalloc.h" |
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return 0; |
return 0; |
} |
} |
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#ifdef KRB5 |
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static int |
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try_krb5_authentication(krb5_context *context, krb5_auth_context *auth_context) |
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{ |
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krb5_error_code problem; |
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const char *tkfile; |
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struct stat buf; |
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krb5_ccache ccache = NULL; |
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const char *remotehost; |
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krb5_data ap; |
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int type; |
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krb5_ap_rep_enc_part *reply = NULL; |
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int ret; |
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memset(&ap, 0, sizeof(ap)); |
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problem = krb5_init_context(context); |
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if (problem) { |
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debug("Kerberos v5: krb5_init_context failed"); |
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ret = 0; |
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goto out; |
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} |
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tkfile = krb5_cc_default_name(*context); |
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if (strncmp(tkfile, "FILE:", 5) == 0) |
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tkfile += 5; |
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if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) { |
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debug("Kerberos v5: could not get default ccache (permission denied)."); |
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ret = 0; |
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goto out; |
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} |
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problem = krb5_cc_default(*context, &ccache); |
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if (problem) { |
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debug("Kerberos v5: krb5_cc_default failed: %s", |
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krb5_get_err_text(*context, problem)); |
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ret = 0; |
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goto out; |
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} |
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remotehost = get_canonical_hostname(1); |
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problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED, |
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"host", remotehost, NULL, ccache, &ap); |
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if (problem) { |
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debug("Kerberos v5: krb5_mk_req failed: %s", |
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krb5_get_err_text(*context, problem)); |
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ret = 0; |
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goto out; |
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} |
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packet_start(SSH_CMSG_AUTH_KERBEROS); |
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packet_put_string((char *) ap.data, ap.length); |
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packet_send(); |
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packet_write_wait(); |
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xfree(ap.data); |
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ap.length = 0; |
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type = packet_read(); |
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switch (type) { |
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case SSH_SMSG_FAILURE: |
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/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
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debug("Kerberos v5 authentication failed."); |
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ret = 0; |
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break; |
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case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
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/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
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debug("Kerberos v5 authentication accepted."); |
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/* Get server's response. */ |
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ap.data = packet_get_string((unsigned int *) &ap.length); |
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packet_check_eom(); |
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/* XXX je to dobre? */ |
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problem = krb5_rd_rep(*context, *auth_context, &ap, &reply); |
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if (problem) { |
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ret = 0; |
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} |
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ret = 1; |
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break; |
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default: |
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packet_disconnect("Protocol error on Kerberos v5 response: %d", |
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type); |
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ret = 0; |
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break; |
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} |
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out: |
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if (ccache != NULL) |
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krb5_cc_close(*context, ccache); |
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if (reply != NULL) |
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krb5_free_ap_rep_enc_part(*context, reply); |
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if (ap.length > 0) |
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krb5_data_free(&ap); |
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return (ret); |
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} |
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static void |
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send_krb5_tgt(krb5_context context, krb5_auth_context auth_context) |
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{ |
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int fd, type; |
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krb5_error_code problem; |
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krb5_data outbuf; |
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krb5_ccache ccache = NULL; |
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krb5_creds creds; |
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krb5_kdc_flags flags; |
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const char *remotehost; |
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memset(&creds, 0, sizeof(creds)); |
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memset(&outbuf, 0, sizeof(outbuf)); |
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fd = packet_get_connection_in(); |
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problem = krb5_auth_con_setaddrs_from_fd(context, auth_context, &fd); |
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if (problem) |
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goto out; |
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problem = krb5_cc_default(context, &ccache); |
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if (problem) |
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goto out; |
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problem = krb5_cc_get_principal(context, ccache, &creds.client); |
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if (problem) |
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goto out; |
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problem = krb5_build_principal(context, &creds.server, |
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strlen(creds.client->realm), creds.client->realm, |
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"krbtgt", creds.client->realm, NULL); |
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if (problem) |
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goto out; |
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creds.times.endtime = 0; |
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flags.i = 0; |
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flags.b.forwarded = 1; |
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flags.b.forwardable = krb5_config_get_bool(context, NULL, |
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"libdefaults", "forwardable", NULL); |
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remotehost = get_canonical_hostname(1); |
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problem = krb5_get_forwarded_creds(context, auth_context, |
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ccache, flags.i, remotehost, &creds, &outbuf); |
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if (problem) |
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goto out; |
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packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
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packet_put_string((char *)outbuf.data, outbuf.length); |
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packet_send(); |
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packet_write_wait(); |
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type = packet_read(); |
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if (type == SSH_SMSG_SUCCESS) { |
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char *pname; |
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krb5_unparse_name(context, creds.client, &pname); |
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debug("Kerberos v5 TGT forwarded (%s).", pname); |
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xfree(pname); |
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} else |
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debug("Kerberos v5 TGT forwarding failed."); |
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return; |
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out: |
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if (problem) |
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debug("Kerberos v5 TGT forwarding failed: %s", |
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krb5_get_err_text(context, problem)); |
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if (creds.client) |
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krb5_free_principal(context, creds.client); |
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if (creds.server) |
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krb5_free_principal(context, creds.server); |
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if (ccache) |
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krb5_cc_close(context, ccache); |
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if (outbuf.data) |
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xfree(outbuf.data); |
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} |
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#endif /* KRB5 */ |
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/* |
/* |
* Tries to authenticate with any string-based challenge/response system. |
* Tries to authenticate with any string-based challenge/response system. |
* Note that the client code is not tied to s/key or TIS. |
* Note that the client code is not tied to s/key or TIS. |
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ssh_userauth1(const char *local_user, const char *server_user, char *host, |
ssh_userauth1(const char *local_user, const char *server_user, char *host, |
Sensitive *sensitive) |
Sensitive *sensitive) |
{ |
{ |
#ifdef KRB5 |
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krb5_context context = NULL; |
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krb5_auth_context auth_context = NULL; |
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#endif |
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int i, type; |
int i, type; |
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if (supported_authentications == 0) |
if (supported_authentications == 0) |
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if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
packet_disconnect("Protocol error: got %d in response to SSH_CMSG_USER", type); |
packet_disconnect("Protocol error: got %d in response to SSH_CMSG_USER", type); |
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#ifdef KRB5 |
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if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
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options.kerberos_authentication) { |
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debug("Trying Kerberos v5 authentication."); |
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if (try_krb5_authentication(&context, &auth_context)) { |
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type = packet_read(); |
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if (type == SSH_SMSG_SUCCESS) |
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goto success; |
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if (type != SSH_SMSG_FAILURE) |
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packet_disconnect("Protocol error: got %d in response to Kerberos v5 auth", type); |
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} |
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} |
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#endif /* KRB5 */ |
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/* |
/* |
* Try .rhosts or /etc/hosts.equiv authentication with RSA host |
* Try .rhosts or /etc/hosts.equiv authentication with RSA host |
* authentication. |
* authentication. |
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/* NOTREACHED */ |
/* NOTREACHED */ |
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success: |
success: |
#ifdef KRB5 |
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/* Try Kerberos v5 TGT passing. */ |
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if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) && |
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options.kerberos_tgt_passing && context && auth_context) { |
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if (options.cipher == SSH_CIPHER_NONE) |
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logit("WARNING: Encryption is disabled! Ticket will be transmitted in the clear!"); |
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send_krb5_tgt(context, auth_context); |
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} |
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if (auth_context) |
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krb5_auth_con_free(context, auth_context); |
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if (context) |
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krb5_free_context(context); |
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#endif |
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return; /* need statement after label */ |
return; /* need statement after label */ |
} |
} |