version 1.41, 2001/10/06 11:18:19 |
version 1.41.2.3, 2002/06/22 07:23:18 |
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RCSID("$OpenBSD$"); |
RCSID("$OpenBSD$"); |
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#include <openssl/bn.h> |
#include <openssl/bn.h> |
#include <openssl/evp.h> |
#include <openssl/md5.h> |
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#ifdef KRB4 |
#ifdef KRB4 |
#include <krb.h> |
#include <krb.h> |
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AuthenticationConnection *auth; |
AuthenticationConnection *auth; |
u_char response[16]; |
u_char response[16]; |
u_int i; |
u_int i; |
int plen, clen; |
|
Key *key; |
Key *key; |
BIGNUM *challenge; |
BIGNUM *challenge; |
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if (!auth) |
if (!auth) |
return 0; |
return 0; |
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challenge = BN_new(); |
if ((challenge = BN_new()) == NULL) |
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fatal("try_agent_authentication: BN_new failed"); |
/* Loop through identities served by the agent. */ |
/* Loop through identities served by the agent. */ |
for (key = ssh_get_first_identity(auth, &comment, 1); |
for (key = ssh_get_first_identity(auth, &comment, 1); |
key != NULL; |
key != NULL; |
key = ssh_get_next_identity(auth, &comment, 1)) { |
key = ssh_get_next_identity(auth, &comment, 1)) { |
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/* Try this identity. */ |
/* Try this identity. */ |
debug("Trying RSA authentication via agent with '%.100s'", comment); |
debug("Trying RSA authentication via agent with '%.100s'", comment); |
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packet_write_wait(); |
packet_write_wait(); |
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/* Wait for server's response. */ |
/* Wait for server's response. */ |
type = packet_read(&plen); |
type = packet_read(); |
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/* The server sends failure if it doesn\'t like our key or |
/* The server sends failure if it doesn\'t like our key or |
does not support RSA authentication. */ |
does not support RSA authentication. */ |
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packet_disconnect("Protocol error during RSA authentication: %d", |
packet_disconnect("Protocol error during RSA authentication: %d", |
type); |
type); |
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packet_get_bignum(challenge, &clen); |
packet_get_bignum(challenge); |
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packet_check_eom(); |
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packet_integrity_check(plen, clen, type); |
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debug("Received RSA challenge from server."); |
debug("Received RSA challenge from server."); |
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/* Ask the agent to decrypt the challenge. */ |
/* Ask the agent to decrypt the challenge. */ |
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packet_write_wait(); |
packet_write_wait(); |
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/* Wait for response from the server. */ |
/* Wait for response from the server. */ |
type = packet_read(&plen); |
type = packet_read(); |
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/* The server returns success if it accepted the authentication. */ |
/* The server returns success if it accepted the authentication. */ |
if (type == SSH_SMSG_SUCCESS) { |
if (type == SSH_SMSG_SUCCESS) { |
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BIGNUM *challenge; |
BIGNUM *challenge; |
Key *public, *private; |
Key *public, *private; |
char buf[300], *passphrase, *comment, *authfile; |
char buf[300], *passphrase, *comment, *authfile; |
int i, type, quit, plen, clen; |
int i, type, quit; |
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public = options.identity_keys[idx]; |
public = options.identity_keys[idx]; |
authfile = options.identity_files[idx]; |
authfile = options.identity_files[idx]; |
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packet_write_wait(); |
packet_write_wait(); |
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/* Wait for server's response. */ |
/* Wait for server's response. */ |
type = packet_read(&plen); |
type = packet_read(); |
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/* |
/* |
* The server responds with failure if it doesn\'t like our key or |
* The server responds with failure if it doesn\'t like our key or |
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packet_disconnect("Protocol error during RSA authentication: %d", type); |
packet_disconnect("Protocol error during RSA authentication: %d", type); |
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/* Get the challenge from the packet. */ |
/* Get the challenge from the packet. */ |
challenge = BN_new(); |
if ((challenge = BN_new()) == NULL) |
packet_get_bignum(challenge, &clen); |
fatal("try_rsa_authentication: BN_new failed"); |
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packet_get_bignum(challenge); |
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packet_check_eom(); |
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packet_integrity_check(plen, clen, type); |
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debug("Received RSA challenge from server."); |
debug("Received RSA challenge from server."); |
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/* |
/* |
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packet_write_wait(); |
packet_write_wait(); |
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/* Expect the server to reject it... */ |
/* Expect the server to reject it... */ |
packet_read_expect(&plen, SSH_SMSG_FAILURE); |
packet_read_expect(SSH_SMSG_FAILURE); |
BN_clear_free(challenge); |
BN_clear_free(challenge); |
return 0; |
return 0; |
} |
} |
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BN_clear_free(challenge); |
BN_clear_free(challenge); |
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/* Wait for response from the server. */ |
/* Wait for response from the server. */ |
type = packet_read(&plen); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) { |
if (type == SSH_SMSG_SUCCESS) { |
debug("RSA authentication accepted by server."); |
debug("RSA authentication accepted by server."); |
return 1; |
return 1; |
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{ |
{ |
int type; |
int type; |
BIGNUM *challenge; |
BIGNUM *challenge; |
int plen, clen; |
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debug("Trying rhosts or /etc/hosts.equiv with RSA host authentication."); |
debug("Trying rhosts or /etc/hosts.equiv with RSA host authentication."); |
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packet_write_wait(); |
packet_write_wait(); |
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/* Wait for server's response. */ |
/* Wait for server's response. */ |
type = packet_read(&plen); |
type = packet_read(); |
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/* The server responds with failure if it doesn't admit our |
/* The server responds with failure if it doesn't admit our |
.rhosts authentication or doesn't know our host key. */ |
.rhosts authentication or doesn't know our host key. */ |
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packet_disconnect("Protocol error during RSA authentication: %d", type); |
packet_disconnect("Protocol error during RSA authentication: %d", type); |
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/* Get the challenge from the packet. */ |
/* Get the challenge from the packet. */ |
challenge = BN_new(); |
if ((challenge = BN_new()) == NULL) |
packet_get_bignum(challenge, &clen); |
fatal("try_rhosts_rsa_authentication: BN_new failed"); |
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packet_get_bignum(challenge); |
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packet_check_eom(); |
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packet_integrity_check(plen, clen, type); |
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debug("Received RSA challenge for host key from server."); |
debug("Received RSA challenge for host key from server."); |
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/* Compute a response to the challenge. */ |
/* Compute a response to the challenge. */ |
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BN_clear_free(challenge); |
BN_clear_free(challenge); |
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/* Wait for response from the server. */ |
/* Wait for response from the server. */ |
type = packet_read(&plen); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) { |
if (type == SSH_SMSG_SUCCESS) { |
debug("Rhosts or /etc/hosts.equiv with RSA host authentication accepted by server."); |
debug("Rhosts or /etc/hosts.equiv with RSA host authentication accepted by server."); |
return 1; |
return 1; |
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char inst[INST_SZ]; |
char inst[INST_SZ]; |
char *realm; |
char *realm; |
CREDENTIALS cred; |
CREDENTIALS cred; |
int r, type, plen; |
int r, type; |
socklen_t slen; |
socklen_t slen; |
Key_schedule schedule; |
Key_schedule schedule; |
u_long checksum, cksum; |
u_long checksum, cksum; |
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/* Don't do anything if we don't have any tickets. */ |
/* Don't do anything if we don't have any tickets. */ |
if (stat(tkt_string(), &st) < 0) |
if (stat(tkt_string(), &st) < 0) |
return 0; |
return 0; |
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strlcpy(inst, (char *)krb_get_phost(get_canonical_hostname(1)), |
strlcpy(inst, (char *)krb_get_phost(get_canonical_hostname(1)), |
INST_SZ); |
INST_SZ); |
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realm = (char *)krb_realmofhost(get_canonical_hostname(1)); |
realm = (char *)krb_realmofhost(get_canonical_hostname(1)); |
if (!realm) { |
if (!realm) { |
debug("Kerberos v4: no realm for %s", get_canonical_hostname(1)); |
debug("Kerberos v4: no realm for %s", get_canonical_hostname(1)); |
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} |
} |
/* This can really be anything. */ |
/* This can really be anything. */ |
checksum = (u_long)getpid(); |
checksum = (u_long)getpid(); |
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r = krb_mk_req(&auth, KRB4_SERVICE_NAME, inst, realm, checksum); |
r = krb_mk_req(&auth, KRB4_SERVICE_NAME, inst, realm, checksum); |
if (r != KSUCCESS) { |
if (r != KSUCCESS) { |
debug("Kerberos v4 krb_mk_req failed: %s", krb_err_txt[r]); |
debug("Kerberos v4 krb_mk_req failed: %s", krb_err_txt[r]); |
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return 0; |
return 0; |
} |
} |
des_key_sched((des_cblock *) cred.session, schedule); |
des_key_sched((des_cblock *) cred.session, schedule); |
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/* Send authentication info to server. */ |
/* Send authentication info to server. */ |
packet_start(SSH_CMSG_AUTH_KERBEROS); |
packet_start(SSH_CMSG_AUTH_KERBEROS); |
packet_put_string((char *) auth.dat, auth.length); |
packet_put_string((char *) auth.dat, auth.length); |
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
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/* Zero the buffer. */ |
/* Zero the buffer. */ |
(void) memset(auth.dat, 0, MAX_KTXT_LEN); |
(void) memset(auth.dat, 0, MAX_KTXT_LEN); |
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slen = sizeof(local); |
slen = sizeof(local); |
memset(&local, 0, sizeof(local)); |
memset(&local, 0, sizeof(local)); |
if (getsockname(packet_get_connection_in(), |
if (getsockname(packet_get_connection_in(), |
(struct sockaddr *)&local, &slen) < 0) |
(struct sockaddr *)&local, &slen) < 0) |
debug("getsockname failed: %s", strerror(errno)); |
debug("getsockname failed: %s", strerror(errno)); |
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slen = sizeof(foreign); |
slen = sizeof(foreign); |
memset(&foreign, 0, sizeof(foreign)); |
memset(&foreign, 0, sizeof(foreign)); |
if (getpeername(packet_get_connection_in(), |
if (getpeername(packet_get_connection_in(), |
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fatal_cleanup(); |
fatal_cleanup(); |
} |
} |
/* Get server reply. */ |
/* Get server reply. */ |
type = packet_read(&plen); |
type = packet_read(); |
switch (type) { |
switch (type) { |
case SSH_SMSG_FAILURE: |
case SSH_SMSG_FAILURE: |
/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
debug("Kerberos v4 authentication failed."); |
debug("Kerberos v4 authentication failed."); |
return 0; |
return 0; |
break; |
break; |
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case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
debug("Kerberos v4 authentication accepted."); |
debug("Kerberos v4 authentication accepted."); |
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/* Get server's response. */ |
/* Get server's response. */ |
reply = packet_get_string((u_int *) &auth.length); |
reply = packet_get_string((u_int *) &auth.length); |
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if (auth.length >= MAX_KTXT_LEN) |
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fatal("Kerberos v4: Malformed response from server"); |
memcpy(auth.dat, reply, auth.length); |
memcpy(auth.dat, reply, auth.length); |
xfree(reply); |
xfree(reply); |
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packet_integrity_check(plen, 4 + auth.length, type); |
packet_check_eom(); |
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/* |
/* |
* If his response isn't properly encrypted with the session |
* If his response isn't properly encrypted with the session |
* key, and the decrypted checksum fails to match, he's |
* key, and the decrypted checksum fails to match, he's |
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memcpy((char *)&cksum, (char *)msg_data.app_data, |
memcpy((char *)&cksum, (char *)msg_data.app_data, |
sizeof(cksum)); |
sizeof(cksum)); |
cksum = ntohl(cksum); |
cksum = ntohl(cksum); |
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/* If it matches, we're golden. */ |
/* If it matches, we're golden. */ |
if (cksum == checksum + 1) { |
if (cksum == checksum + 1) { |
debug("Kerberos v4 challenge successful."); |
debug("Kerberos v4 challenge successful."); |
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} else |
} else |
packet_disconnect("Kerberos v4 challenge failed!"); |
packet_disconnect("Kerberos v4 challenge failed!"); |
break; |
break; |
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default: |
default: |
packet_disconnect("Protocol error on Kerberos v4 response: %d", type); |
packet_disconnect("Protocol error on Kerberos v4 response: %d", type); |
} |
} |
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krb5_ccache ccache = NULL; |
krb5_ccache ccache = NULL; |
const char *remotehost; |
const char *remotehost; |
krb5_data ap; |
krb5_data ap; |
int type, payload_len; |
int type; |
krb5_ap_rep_enc_part *reply = NULL; |
krb5_ap_rep_enc_part *reply = NULL; |
int ret; |
int ret; |
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memset(&ap, 0, sizeof(ap)); |
memset(&ap, 0, sizeof(ap)); |
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problem = krb5_init_context(context); |
problem = krb5_init_context(context); |
if (problem) { |
if (problem) { |
debug("Kerberos v5: krb5_init_context failed"); |
debug("Kerberos v5: krb5_init_context failed"); |
ret = 0; |
ret = 0; |
goto out; |
goto out; |
} |
} |
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tkfile = krb5_cc_default_name(*context); |
tkfile = krb5_cc_default_name(*context); |
if (strncmp(tkfile, "FILE:", 5) == 0) |
if (strncmp(tkfile, "FILE:", 5) == 0) |
tkfile += 5; |
tkfile += 5; |
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if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) { |
if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) { |
debug("Kerberos v5: could not get default ccache (permission denied)."); |
debug("Kerberos v5: could not get default ccache (permission denied)."); |
ret = 0; |
ret = 0; |
goto out; |
goto out; |
} |
} |
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problem = krb5_cc_default(*context, &ccache); |
problem = krb5_cc_default(*context, &ccache); |
if (problem) { |
if (problem) { |
debug("Kerberos v5: krb5_cc_default failed: %s", |
debug("Kerberos v5: krb5_cc_default failed: %s", |
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ret = 0; |
ret = 0; |
goto out; |
goto out; |
} |
} |
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remotehost = get_canonical_hostname(1); |
remotehost = get_canonical_hostname(1); |
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problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED, |
problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED, |
"host", remotehost, NULL, ccache, &ap); |
"host", remotehost, NULL, ccache, &ap); |
if (problem) { |
if (problem) { |
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ret = 0; |
ret = 0; |
goto out; |
goto out; |
} |
} |
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packet_start(SSH_CMSG_AUTH_KERBEROS); |
packet_start(SSH_CMSG_AUTH_KERBEROS); |
packet_put_string((char *) ap.data, ap.length); |
packet_put_string((char *) ap.data, ap.length); |
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
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xfree(ap.data); |
xfree(ap.data); |
ap.length = 0; |
ap.length = 0; |
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type = packet_read(&payload_len); |
type = packet_read(); |
switch (type) { |
switch (type) { |
case SSH_SMSG_FAILURE: |
case SSH_SMSG_FAILURE: |
/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
debug("Kerberos v5 authentication failed."); |
debug("Kerberos v5 authentication failed."); |
ret = 0; |
ret = 0; |
break; |
break; |
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case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
debug("Kerberos v5 authentication accepted."); |
debug("Kerberos v5 authentication accepted."); |
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/* Get server's response. */ |
/* Get server's response. */ |
ap.data = packet_get_string((unsigned int *) &ap.length); |
ap.data = packet_get_string((unsigned int *) &ap.length); |
|
packet_check_eom(); |
packet_integrity_check(payload_len, 4 + ap.length, type); |
/* XXX je to dobre? */ |
/* XXX je to dobre? */ |
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problem = krb5_rd_rep(*context, *auth_context, &ap, &reply); |
problem = krb5_rd_rep(*context, *auth_context, &ap, &reply); |
if (problem) { |
if (problem) { |
|
ret = 0; |
ret = 0; |
} |
} |
ret = 1; |
ret = 1; |
break; |
break; |
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default: |
default: |
packet_disconnect("Protocol error on Kerberos v5 response: %d", |
packet_disconnect("Protocol error on Kerberos v5 response: %d", |
type); |
type); |
ret = 0; |
ret = 0; |
break; |
break; |
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} |
} |
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out: |
out: |
if (ccache != NULL) |
if (ccache != NULL) |
krb5_cc_close(*context, ccache); |
krb5_cc_close(*context, ccache); |
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krb5_free_ap_rep_enc_part(*context, reply); |
krb5_free_ap_rep_enc_part(*context, reply); |
if (ap.length > 0) |
if (ap.length > 0) |
krb5_data_free(&ap); |
krb5_data_free(&ap); |
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return (ret); |
return (ret); |
} |
} |
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static void |
static void |
send_krb5_tgt(krb5_context context, krb5_auth_context auth_context) |
send_krb5_tgt(krb5_context context, krb5_auth_context auth_context) |
{ |
{ |
int fd, type, payload_len; |
int fd, type; |
krb5_error_code problem; |
krb5_error_code problem; |
krb5_data outbuf; |
krb5_data outbuf; |
krb5_ccache ccache = NULL; |
krb5_ccache ccache = NULL; |
krb5_creds creds; |
krb5_creds creds; |
krb5_kdc_flags flags; |
krb5_kdc_flags flags; |
const char *remotehost; |
const char *remotehost; |
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memset(&creds, 0, sizeof(creds)); |
memset(&creds, 0, sizeof(creds)); |
memset(&outbuf, 0, sizeof(outbuf)); |
memset(&outbuf, 0, sizeof(outbuf)); |
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fd = packet_get_connection_in(); |
fd = packet_get_connection_in(); |
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problem = krb5_auth_con_setaddrs_from_fd(context, auth_context, &fd); |
problem = krb5_auth_con_setaddrs_from_fd(context, auth_context, &fd); |
if (problem) |
if (problem) |
goto out; |
goto out; |
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problem = krb5_cc_default(context, &ccache); |
problem = krb5_cc_default(context, &ccache); |
if (problem) |
if (problem) |
goto out; |
goto out; |
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problem = krb5_cc_get_principal(context, ccache, &creds.client); |
problem = krb5_cc_get_principal(context, ccache, &creds.client); |
if (problem) |
if (problem) |
goto out; |
goto out; |
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problem = krb5_build_principal(context, &creds.server, |
problem = krb5_build_principal(context, &creds.server, |
strlen(creds.client->realm), creds.client->realm, |
strlen(creds.client->realm), creds.client->realm, |
"krbtgt", creds.client->realm, NULL); |
"krbtgt", creds.client->realm, NULL); |
if (problem) |
if (problem) |
goto out; |
goto out; |
|
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creds.times.endtime = 0; |
creds.times.endtime = 0; |
|
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flags.i = 0; |
flags.i = 0; |
flags.b.forwarded = 1; |
flags.b.forwarded = 1; |
flags.b.forwardable = krb5_config_get_bool(context, NULL, |
flags.b.forwardable = krb5_config_get_bool(context, NULL, |
"libdefaults", "forwardable", NULL); |
"libdefaults", "forwardable", NULL); |
|
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remotehost = get_canonical_hostname(1); |
remotehost = get_canonical_hostname(1); |
|
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problem = krb5_get_forwarded_creds(context, auth_context, |
problem = krb5_get_forwarded_creds(context, auth_context, |
ccache, flags.i, remotehost, &creds, &outbuf); |
ccache, flags.i, remotehost, &creds, &outbuf); |
if (problem) |
if (problem) |
goto out; |
goto out; |
|
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packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
packet_put_string((char *)outbuf.data, outbuf.length); |
packet_put_string((char *)outbuf.data, outbuf.length); |
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
|
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type = packet_read(&payload_len); |
type = packet_read(); |
|
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if (type == SSH_SMSG_SUCCESS) { |
if (type == SSH_SMSG_SUCCESS) { |
char *pname; |
char *pname; |
|
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krb5_unparse_name(context, creds.client, &pname); |
krb5_unparse_name(context, creds.client, &pname); |
debug("Kerberos v5 TGT forwarded (%s).", pname); |
debug("Kerberos v5 TGT forwarded (%s).", pname); |
xfree(pname); |
xfree(pname); |
} else |
} else |
debug("Kerberos v5 TGT forwarding failed."); |
debug("Kerberos v5 TGT forwarding failed."); |
|
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return; |
return; |
|
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out: |
out: |
if (problem) |
if (problem) |
debug("Kerberos v5 TGT forwarding failed: %s", |
debug("Kerberos v5 TGT forwarding failed: %s", |
|
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CREDENTIALS *creds; |
CREDENTIALS *creds; |
struct stat st; |
struct stat st; |
char buffer[4096], pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ]; |
char buffer[4096], pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ]; |
int problem, type, len; |
int problem, type; |
|
|
/* Don't do anything if we don't have any tickets. */ |
/* Don't do anything if we don't have any tickets. */ |
if (stat(tkt_string(), &st) < 0) |
if (stat(tkt_string(), &st) < 0) |
return; |
return; |
|
|
creds = xmalloc(sizeof(*creds)); |
creds = xmalloc(sizeof(*creds)); |
|
|
problem = krb_get_tf_fullname(TKT_FILE, pname, pinst, prealm); |
problem = krb_get_tf_fullname(TKT_FILE, pname, pinst, prealm); |
if (problem) |
if (problem) |
goto out; |
goto out; |
|
|
problem = krb_get_cred("krbtgt", prealm, prealm, creds); |
problem = krb_get_cred("krbtgt", prealm, prealm, creds); |
if (problem) |
if (problem) |
goto out; |
goto out; |
|
|
if (time(0) > krb_life_to_time(creds->issue_date, creds->lifetime)) { |
if (time(0) > krb_life_to_time(creds->issue_date, creds->lifetime)) { |
problem = RD_AP_EXP; |
problem = RD_AP_EXP; |
goto out; |
goto out; |
} |
} |
creds_to_radix(creds, (u_char *)buffer, sizeof(buffer)); |
creds_to_radix(creds, (u_char *)buffer, sizeof(buffer)); |
|
|
packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
packet_put_cstring(buffer); |
packet_put_cstring(buffer); |
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
|
|
type = packet_read(&len); |
type = packet_read(); |
|
|
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
debug("Kerberos v4 TGT forwarded (%s%s%s@%s).", |
debug("Kerberos v4 TGT forwarded (%s%s%s@%s).", |
creds->pname, creds->pinst[0] ? "." : "", |
creds->pname, creds->pinst[0] ? "." : "", |
creds->pinst, creds->realm); |
creds->pinst, creds->realm); |
else |
else |
debug("Kerberos v4 TGT rejected."); |
debug("Kerberos v4 TGT rejected."); |
|
|
xfree(creds); |
xfree(creds); |
return; |
return; |
|
|
out: |
out: |
debug("Kerberos v4 TGT passing failed: %s", krb_err_txt[problem]); |
debug("Kerberos v4 TGT passing failed: %s", krb_err_txt[problem]); |
xfree(creds); |
xfree(creds); |
|
|
int i, type, len; |
int i, type, len; |
char buf[2048], *p, *server_cell; |
char buf[2048], *p, *server_cell; |
char buffer[8192]; |
char buffer[8192]; |
|
|
/* Move over ktc_GetToken, here's something leaner. */ |
/* Move over ktc_GetToken, here's something leaner. */ |
for (i = 0; i < 100; i++) { /* just in case */ |
for (i = 0; i < 100; i++) { /* just in case */ |
parms.in = (char *) &i; |
parms.in = (char *) &i; |
|
|
if (k_pioctl(0, VIOCGETTOK, &parms, 0) != 0) |
if (k_pioctl(0, VIOCGETTOK, &parms, 0) != 0) |
break; |
break; |
p = buf; |
p = buf; |
|
|
/* Get secret token. */ |
/* Get secret token. */ |
memcpy(&creds.ticket_st.length, p, sizeof(u_int)); |
memcpy(&creds.ticket_st.length, p, sizeof(u_int)); |
if (creds.ticket_st.length > MAX_KTXT_LEN) |
if (creds.ticket_st.length > MAX_KTXT_LEN) |
|
|
p += sizeof(u_int); |
p += sizeof(u_int); |
memcpy(creds.ticket_st.dat, p, creds.ticket_st.length); |
memcpy(creds.ticket_st.dat, p, creds.ticket_st.length); |
p += creds.ticket_st.length; |
p += creds.ticket_st.length; |
|
|
/* Get clear token. */ |
/* Get clear token. */ |
memcpy(&len, p, sizeof(len)); |
memcpy(&len, p, sizeof(len)); |
if (len != sizeof(struct ClearToken)) |
if (len != sizeof(struct ClearToken)) |
|
|
p += len; |
p += len; |
p += sizeof(len); /* primary flag */ |
p += sizeof(len); /* primary flag */ |
server_cell = p; |
server_cell = p; |
|
|
/* Flesh out our credentials. */ |
/* Flesh out our credentials. */ |
strlcpy(creds.service, "afs", sizeof(creds.service)); |
strlcpy(creds.service, "afs", sizeof(creds.service)); |
creds.instance[0] = '\0'; |
creds.instance[0] = '\0'; |
|
|
creds.kvno = ct.AuthHandle; |
creds.kvno = ct.AuthHandle; |
snprintf(creds.pname, sizeof(creds.pname), "AFS ID %d", ct.ViceId); |
snprintf(creds.pname, sizeof(creds.pname), "AFS ID %d", ct.ViceId); |
creds.pinst[0] = '\0'; |
creds.pinst[0] = '\0'; |
|
|
/* Encode token, ship it off. */ |
/* Encode token, ship it off. */ |
if (creds_to_radix(&creds, (u_char *)buffer, |
if (creds_to_radix(&creds, (u_char *)buffer, |
sizeof(buffer)) <= 0) |
sizeof(buffer)) <= 0) |
|
|
|
|
/* Roger, Roger. Clearance, Clarence. What's your vector, |
/* Roger, Roger. Clearance, Clarence. What's your vector, |
Victor? */ |
Victor? */ |
type = packet_read(&len); |
type = packet_read(); |
|
|
if (type == SSH_SMSG_FAILURE) |
if (type == SSH_SMSG_FAILURE) |
debug("AFS token for cell %s rejected.", server_cell); |
debug("AFS token for cell %s rejected.", server_cell); |
else if (type != SSH_SMSG_SUCCESS) |
else if (type != SSH_SMSG_SUCCESS) |
|
|
try_challenge_response_authentication(void) |
try_challenge_response_authentication(void) |
{ |
{ |
int type, i; |
int type, i; |
int payload_len; |
|
u_int clen; |
u_int clen; |
char prompt[1024]; |
char prompt[1024]; |
char *challenge, *response; |
char *challenge, *response; |
|
|
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
|
|
type = packet_read(&payload_len); |
type = packet_read(); |
if (type != SSH_SMSG_FAILURE && |
if (type != SSH_SMSG_FAILURE && |
type != SSH_SMSG_AUTH_TIS_CHALLENGE) { |
type != SSH_SMSG_AUTH_TIS_CHALLENGE) { |
packet_disconnect("Protocol error: got %d in response " |
packet_disconnect("Protocol error: got %d in response " |
|
|
return 0; |
return 0; |
} |
} |
challenge = packet_get_string(&clen); |
challenge = packet_get_string(&clen); |
packet_integrity_check(payload_len, (4 + clen), type); |
packet_check_eom(); |
snprintf(prompt, sizeof prompt, "%s%s", challenge, |
snprintf(prompt, sizeof prompt, "%s%s", challenge, |
strchr(challenge, '\n') ? "" : "\nResponse: "); |
strchr(challenge, '\n') ? "" : "\nResponse: "); |
xfree(challenge); |
xfree(challenge); |
if (i != 0) |
if (i != 0) |
error("Permission denied, please try again."); |
error("Permission denied, please try again."); |
if (options.cipher == SSH_CIPHER_NONE) |
if (options.cipher == SSH_CIPHER_NONE) |
log("WARNING: Encryption is disabled! " |
log("WARNING: Encryption is disabled! " |
"Reponse will be transmitted in clear text."); |
"Response will be transmitted in clear text."); |
response = read_passphrase(prompt, 0); |
response = read_passphrase(prompt, 0); |
if (strcmp(response, "") == 0) { |
if (strcmp(response, "") == 0) { |
xfree(response); |
xfree(response); |
|
|
xfree(response); |
xfree(response); |
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
type = packet_read(&payload_len); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
return 1; |
return 1; |
if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
|
|
static int |
static int |
try_password_authentication(char *prompt) |
try_password_authentication(char *prompt) |
{ |
{ |
int type, i, payload_len; |
int type, i; |
char *password; |
char *password; |
|
|
debug("Doing password authentication."); |
debug("Doing password authentication."); |
|
|
packet_send(); |
packet_send(); |
packet_write_wait(); |
packet_write_wait(); |
|
|
type = packet_read(&payload_len); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
return 1; |
return 1; |
if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
|
|
{ |
{ |
int i; |
int i; |
BIGNUM *key; |
BIGNUM *key; |
RSA *host_key; |
Key *host_key, *server_key; |
RSA *public_key; |
|
Key k; |
|
int bits, rbits; |
int bits, rbits; |
int ssh_cipher_default = SSH_CIPHER_3DES; |
int ssh_cipher_default = SSH_CIPHER_3DES; |
u_char session_key[SSH_SESSION_KEY_LENGTH]; |
u_char session_key[SSH_SESSION_KEY_LENGTH]; |
u_char cookie[8]; |
u_char cookie[8]; |
u_int supported_ciphers; |
u_int supported_ciphers; |
u_int server_flags, client_flags; |
u_int server_flags, client_flags; |
int payload_len, clen, sum_len = 0; |
|
u_int32_t rand = 0; |
u_int32_t rand = 0; |
|
|
debug("Waiting for server public key."); |
debug("Waiting for server public key."); |
|
|
/* Wait for a public key packet from the server. */ |
/* Wait for a public key packet from the server. */ |
packet_read_expect(&payload_len, SSH_SMSG_PUBLIC_KEY); |
packet_read_expect(SSH_SMSG_PUBLIC_KEY); |
|
|
/* Get cookie from the packet. */ |
/* Get cookie from the packet. */ |
for (i = 0; i < 8; i++) |
for (i = 0; i < 8; i++) |
cookie[i] = packet_get_char(); |
cookie[i] = packet_get_char(); |
|
|
/* Get the public key. */ |
/* Get the public key. */ |
public_key = RSA_new(); |
server_key = key_new(KEY_RSA1); |
bits = packet_get_int();/* bits */ |
bits = packet_get_int(); |
public_key->e = BN_new(); |
packet_get_bignum(server_key->rsa->e); |
packet_get_bignum(public_key->e, &clen); |
packet_get_bignum(server_key->rsa->n); |
sum_len += clen; |
|
public_key->n = BN_new(); |
|
packet_get_bignum(public_key->n, &clen); |
|
sum_len += clen; |
|
|
|
rbits = BN_num_bits(public_key->n); |
rbits = BN_num_bits(server_key->rsa->n); |
if (bits != rbits) { |
if (bits != rbits) { |
log("Warning: Server lies about size of server public key: " |
log("Warning: Server lies about size of server public key: " |
"actual size is %d bits vs. announced %d.", rbits, bits); |
"actual size is %d bits vs. announced %d.", rbits, bits); |
log("Warning: This may be due to an old implementation of ssh."); |
log("Warning: This may be due to an old implementation of ssh."); |
} |
} |
/* Get the host key. */ |
/* Get the host key. */ |
host_key = RSA_new(); |
host_key = key_new(KEY_RSA1); |
bits = packet_get_int();/* bits */ |
bits = packet_get_int(); |
host_key->e = BN_new(); |
packet_get_bignum(host_key->rsa->e); |
packet_get_bignum(host_key->e, &clen); |
packet_get_bignum(host_key->rsa->n); |
sum_len += clen; |
|
host_key->n = BN_new(); |
|
packet_get_bignum(host_key->n, &clen); |
|
sum_len += clen; |
|
|
|
rbits = BN_num_bits(host_key->n); |
rbits = BN_num_bits(host_key->rsa->n); |
if (bits != rbits) { |
if (bits != rbits) { |
log("Warning: Server lies about size of server host key: " |
log("Warning: Server lies about size of server host key: " |
"actual size is %d bits vs. announced %d.", rbits, bits); |
"actual size is %d bits vs. announced %d.", rbits, bits); |
|
|
|
|
supported_ciphers = packet_get_int(); |
supported_ciphers = packet_get_int(); |
supported_authentications = packet_get_int(); |
supported_authentications = packet_get_int(); |
|
packet_check_eom(); |
|
|
debug("Received server public key (%d bits) and host key (%d bits).", |
debug("Received server public key (%d bits) and host key (%d bits).", |
BN_num_bits(public_key->n), BN_num_bits(host_key->n)); |
BN_num_bits(server_key->rsa->n), BN_num_bits(host_key->rsa->n)); |
|
|
packet_integrity_check(payload_len, |
if (verify_host_key(host, hostaddr, host_key) == -1) |
8 + 4 + sum_len + 0 + 4 + 0 + 0 + 4 + 4 + 4, |
|
SSH_SMSG_PUBLIC_KEY); |
|
k.type = KEY_RSA1; |
|
k.rsa = host_key; |
|
if (verify_host_key(host, hostaddr, &k) == -1) |
|
fatal("Host key verification failed."); |
fatal("Host key verification failed."); |
|
|
client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN; |
client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN; |
|
|
compute_session_id(session_id, cookie, host_key->n, public_key->n); |
compute_session_id(session_id, cookie, host_key->rsa->n, server_key->rsa->n); |
|
|
/* Generate a session key. */ |
/* Generate a session key. */ |
arc4random_stir(); |
arc4random_stir(); |
|
|
* is the highest byte of the integer. The session key is xored with |
* is the highest byte of the integer. The session key is xored with |
* the first 16 bytes of the session id. |
* the first 16 bytes of the session id. |
*/ |
*/ |
key = BN_new(); |
if ((key = BN_new()) == NULL) |
|
fatal("respond_to_rsa_challenge: BN_new failed"); |
BN_set_word(key, 0); |
BN_set_word(key, 0); |
for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) { |
for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) { |
BN_lshift(key, key, 8); |
BN_lshift(key, key, 8); |
|
|
* Encrypt the integer using the public key and host key of the |
* Encrypt the integer using the public key and host key of the |
* server (key with smaller modulus first). |
* server (key with smaller modulus first). |
*/ |
*/ |
if (BN_cmp(public_key->n, host_key->n) < 0) { |
if (BN_cmp(server_key->rsa->n, host_key->rsa->n) < 0) { |
/* Public key has smaller modulus. */ |
/* Public key has smaller modulus. */ |
if (BN_num_bits(host_key->n) < |
if (BN_num_bits(host_key->rsa->n) < |
BN_num_bits(public_key->n) + SSH_KEY_BITS_RESERVED) { |
BN_num_bits(server_key->rsa->n) + SSH_KEY_BITS_RESERVED) { |
fatal("respond_to_rsa_challenge: host_key %d < public_key %d + " |
fatal("respond_to_rsa_challenge: host_key %d < server_key %d + " |
"SSH_KEY_BITS_RESERVED %d", |
"SSH_KEY_BITS_RESERVED %d", |
BN_num_bits(host_key->n), |
BN_num_bits(host_key->rsa->n), |
BN_num_bits(public_key->n), |
BN_num_bits(server_key->rsa->n), |
SSH_KEY_BITS_RESERVED); |
SSH_KEY_BITS_RESERVED); |
} |
} |
rsa_public_encrypt(key, key, public_key); |
rsa_public_encrypt(key, key, server_key->rsa); |
rsa_public_encrypt(key, key, host_key); |
rsa_public_encrypt(key, key, host_key->rsa); |
} else { |
} else { |
/* Host key has smaller modulus (or they are equal). */ |
/* Host key has smaller modulus (or they are equal). */ |
if (BN_num_bits(public_key->n) < |
if (BN_num_bits(server_key->rsa->n) < |
BN_num_bits(host_key->n) + SSH_KEY_BITS_RESERVED) { |
BN_num_bits(host_key->rsa->n) + SSH_KEY_BITS_RESERVED) { |
fatal("respond_to_rsa_challenge: public_key %d < host_key %d + " |
fatal("respond_to_rsa_challenge: server_key %d < host_key %d + " |
"SSH_KEY_BITS_RESERVED %d", |
"SSH_KEY_BITS_RESERVED %d", |
BN_num_bits(public_key->n), |
BN_num_bits(server_key->rsa->n), |
BN_num_bits(host_key->n), |
BN_num_bits(host_key->rsa->n), |
SSH_KEY_BITS_RESERVED); |
SSH_KEY_BITS_RESERVED); |
} |
} |
rsa_public_encrypt(key, key, host_key); |
rsa_public_encrypt(key, key, host_key->rsa); |
rsa_public_encrypt(key, key, public_key); |
rsa_public_encrypt(key, key, server_key->rsa); |
} |
} |
|
|
/* Destroy the public keys since we no longer need them. */ |
/* Destroy the public keys since we no longer need them. */ |
RSA_free(public_key); |
key_free(server_key); |
RSA_free(host_key); |
key_free(host_key); |
|
|
if (options.cipher == SSH_CIPHER_NOT_SET) { |
if (options.cipher == SSH_CIPHER_NOT_SET) { |
if (cipher_mask_ssh1(1) & supported_ciphers & (1 << ssh_cipher_default)) |
if (cipher_mask_ssh1(1) & supported_ciphers & (1 << ssh_cipher_default)) |
|
|
/* Check that the selected cipher is supported. */ |
/* Check that the selected cipher is supported. */ |
if (!(supported_ciphers & (1 << options.cipher))) |
if (!(supported_ciphers & (1 << options.cipher))) |
fatal("Selected cipher type %.100s not supported by server.", |
fatal("Selected cipher type %.100s not supported by server.", |
cipher_name(options.cipher)); |
cipher_name(options.cipher)); |
|
|
debug("Encryption type: %.100s", cipher_name(options.cipher)); |
debug("Encryption type: %.100s", cipher_name(options.cipher)); |
|
|
|
|
* Expect a success message from the server. Note that this message |
* Expect a success message from the server. Note that this message |
* will be received in encrypted form. |
* will be received in encrypted form. |
*/ |
*/ |
packet_read_expect(&payload_len, SSH_SMSG_SUCCESS); |
packet_read_expect(SSH_SMSG_SUCCESS); |
|
|
debug("Received encrypted confirmation."); |
debug("Received encrypted confirmation."); |
} |
} |
|
|
*/ |
*/ |
void |
void |
ssh_userauth1(const char *local_user, const char *server_user, char *host, |
ssh_userauth1(const char *local_user, const char *server_user, char *host, |
Key **keys, int nkeys) |
Sensitive *sensitive) |
{ |
{ |
#ifdef KRB5 |
#ifdef KRB5 |
krb5_context context = NULL; |
krb5_context context = NULL; |
krb5_auth_context auth_context = NULL; |
krb5_auth_context auth_context = NULL; |
#endif |
#endif |
int i, type; |
int i, type; |
int payload_len; |
|
|
|
if (supported_authentications == 0) |
if (supported_authentications == 0) |
fatal("ssh_userauth1: server supports no auth methods"); |
fatal("ssh_userauth1: server supports no auth methods"); |
|
|
|
|
* needed (the user has no password). Otherwise the server responds |
* needed (the user has no password). Otherwise the server responds |
* with failure. |
* with failure. |
*/ |
*/ |
type = packet_read(&payload_len); |
type = packet_read(); |
|
|
/* check whether the connection was accepted without authentication. */ |
/* check whether the connection was accepted without authentication. */ |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
goto success; |
goto success; |
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); |
|
|
#ifdef KRB5 |
#ifdef KRB5 |
if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
options.kerberos_authentication) { |
options.kerberos_authentication) { |
debug("Trying Kerberos v5 authentication."); |
debug("Trying Kerberos v5 authentication."); |
|
|
if (try_krb5_authentication(&context, &auth_context)) { |
if (try_krb5_authentication(&context, &auth_context)) { |
type = packet_read(&payload_len); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
goto success; |
goto success; |
if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
|
|
} |
} |
} |
} |
#endif /* KRB5 */ |
#endif /* KRB5 */ |
|
|
#ifdef KRB4 |
#ifdef KRB4 |
if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
options.kerberos_authentication) { |
options.kerberos_authentication) { |
debug("Trying Kerberos v4 authentication."); |
debug("Trying Kerberos v4 authentication."); |
|
|
if (try_krb4_authentication()) { |
if (try_krb4_authentication()) { |
type = packet_read(&payload_len); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
goto success; |
goto success; |
if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
|
|
} |
} |
} |
} |
#endif /* KRB4 */ |
#endif /* KRB4 */ |
|
|
/* |
/* |
* Use rhosts authentication if running in privileged socket and we |
* Use rhosts authentication if running in privileged socket and we |
* do not wish to remain anonymous. |
* do not wish to remain anonymous. |
|
|
packet_write_wait(); |
packet_write_wait(); |
|
|
/* The server should respond with success or failure. */ |
/* The server should respond with success or failure. */ |
type = packet_read(&payload_len); |
type = packet_read(); |
if (type == SSH_SMSG_SUCCESS) |
if (type == SSH_SMSG_SUCCESS) |
goto success; |
goto success; |
if (type != SSH_SMSG_FAILURE) |
if (type != SSH_SMSG_FAILURE) |
|
|
*/ |
*/ |
if ((supported_authentications & (1 << SSH_AUTH_RHOSTS_RSA)) && |
if ((supported_authentications & (1 << SSH_AUTH_RHOSTS_RSA)) && |
options.rhosts_rsa_authentication) { |
options.rhosts_rsa_authentication) { |
for (i = 0; i < nkeys; i++) { |
for (i = 0; i < sensitive->nkeys; i++) { |
if (keys[i] != NULL && keys[i]->type == KEY_RSA1 && |
if (sensitive->keys[i] != NULL && |
try_rhosts_rsa_authentication(local_user, keys[i])) |
sensitive->keys[i]->type == KEY_RSA1 && |
|
try_rhosts_rsa_authentication(local_user, |
|
sensitive->keys[i])) |
goto success; |
goto success; |
} |
} |
} |
} |
|
|
if (context) |
if (context) |
krb5_free_context(context); |
krb5_free_context(context); |
#endif |
#endif |
|
|
#ifdef AFS |
#ifdef AFS |
/* Try Kerberos v4 TGT passing if the server supports it. */ |
/* Try Kerberos v4 TGT passing if the server supports it. */ |
if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) && |
if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) && |