version 1.32, 2000/10/14 12:19:45 |
version 1.32.2.5, 2001/09/27 00:15:41 |
|
|
#include "includes.h" |
#include "includes.h" |
RCSID("$OpenBSD$"); |
RCSID("$OpenBSD$"); |
|
|
|
#include <openssl/rsa.h> |
|
#include <openssl/md5.h> |
|
|
#include "rsa.h" |
#include "rsa.h" |
#include "packet.h" |
#include "packet.h" |
#include "xmalloc.h" |
#include "xmalloc.h" |
#include "ssh.h" |
#include "ssh1.h" |
#include "mpaux.h" |
#include "mpaux.h" |
#include "uidswap.h" |
#include "uidswap.h" |
#include "match.h" |
#include "match.h" |
#include "servconf.h" |
|
#include "auth-options.h" |
#include "auth-options.h" |
|
#include "pathnames.h" |
|
#include "log.h" |
|
#include "servconf.h" |
|
#include "auth.h" |
|
|
#include <openssl/rsa.h> |
|
#include <openssl/md5.h> |
|
|
|
|
|
/* import */ |
/* import */ |
extern ServerOptions options; |
extern ServerOptions options; |
|
|
|
|
* Session identifier that is used to bind key exchange and authentication |
* Session identifier that is used to bind key exchange and authentication |
* responses to a particular session. |
* responses to a particular session. |
*/ |
*/ |
extern unsigned char session_id[16]; |
extern u_char session_id[16]; |
|
|
/* |
/* |
* The .ssh/authorized_keys file contains public keys, one per line, in the |
* The .ssh/authorized_keys file contains public keys, one per line, in the |
|
|
{ |
{ |
BIGNUM *challenge, *encrypted_challenge; |
BIGNUM *challenge, *encrypted_challenge; |
BN_CTX *ctx; |
BN_CTX *ctx; |
unsigned char buf[32], mdbuf[16], response[16]; |
u_char buf[32], mdbuf[16], response[16]; |
MD5_CTX md; |
MD5_CTX md; |
unsigned int i; |
u_int i; |
int plen, len; |
int plen, len; |
|
|
encrypted_challenge = BN_new(); |
encrypted_challenge = BN_new(); |
|
|
int |
int |
auth_rsa(struct passwd *pw, BIGNUM *client_n) |
auth_rsa(struct passwd *pw, BIGNUM *client_n) |
{ |
{ |
char line[8192], file[1024]; |
char line[8192], *file; |
int authenticated; |
int authenticated; |
unsigned int bits; |
u_int bits; |
FILE *f; |
FILE *f; |
unsigned long linenum = 0; |
u_long linenum = 0; |
struct stat st; |
struct stat st; |
RSA *pk; |
RSA *pk; |
|
|
|
|
return 0; |
return 0; |
|
|
/* Temporarily use the user's uid. */ |
/* Temporarily use the user's uid. */ |
temporarily_use_uid(pw->pw_uid); |
temporarily_use_uid(pw); |
|
|
/* The authorized keys. */ |
/* The authorized keys. */ |
snprintf(file, sizeof file, "%.500s/%.100s", pw->pw_dir, |
file = authorized_keys_file(pw); |
SSH_USER_PERMITTED_KEYS); |
debug("trying public RSA key file %s", file); |
|
|
/* Fail quietly if file does not exist */ |
/* Fail quietly if file does not exist */ |
if (stat(file, &st) < 0) { |
if (stat(file, &st) < 0) { |
/* Restore the privileged uid. */ |
/* Restore the privileged uid. */ |
restore_uid(); |
restore_uid(); |
|
xfree(file); |
return 0; |
return 0; |
} |
} |
/* Open the file containing the authorized keys. */ |
/* Open the file containing the authorized keys. */ |
|
|
restore_uid(); |
restore_uid(); |
packet_send_debug("Could not open %.900s for reading.", file); |
packet_send_debug("Could not open %.900s for reading.", file); |
packet_send_debug("If your home is on an NFS volume, it may need to be world-readable."); |
packet_send_debug("If your home is on an NFS volume, it may need to be world-readable."); |
|
xfree(file); |
return 0; |
return 0; |
} |
} |
if (options.strict_modes) { |
if (options.strict_modes && |
int fail = 0; |
secure_filename(f, file, pw, line, sizeof(line)) != 0) { |
char buf[1024]; |
xfree(file); |
/* Check open file in order to avoid open/stat races */ |
fclose(f); |
if (fstat(fileno(f), &st) < 0 || |
log("Authentication refused: %s", line); |
(st.st_uid != 0 && st.st_uid != pw->pw_uid) || |
packet_send_debug("Authentication refused: %s", line); |
(st.st_mode & 022) != 0) { |
restore_uid(); |
snprintf(buf, sizeof buf, "RSA authentication refused for %.100s: " |
return 0; |
"bad ownership or modes for '%s'.", pw->pw_name, file); |
|
fail = 1; |
|
} else { |
|
/* Check path to SSH_USER_PERMITTED_KEYS */ |
|
int i; |
|
static const char *check[] = { |
|
"", SSH_USER_DIR, NULL |
|
}; |
|
for (i = 0; check[i]; i++) { |
|
snprintf(line, sizeof line, "%.500s/%.100s", pw->pw_dir, check[i]); |
|
if (stat(line, &st) < 0 || |
|
(st.st_uid != 0 && st.st_uid != pw->pw_uid) || |
|
(st.st_mode & 022) != 0) { |
|
snprintf(buf, sizeof buf, "RSA authentication refused for %.100s: " |
|
"bad ownership or modes for '%s'.", pw->pw_name, line); |
|
fail = 1; |
|
break; |
|
} |
|
} |
|
} |
|
if (fail) { |
|
fclose(f); |
|
log("%s",buf); |
|
packet_send_debug("%s",buf); |
|
restore_uid(); |
|
return 0; |
|
} |
|
} |
} |
/* Flag indicating whether authentication has succeeded. */ |
/* Flag indicating whether authentication has succeeded. */ |
authenticated = 0; |
authenticated = 0; |
|
|
} |
} |
} else |
} else |
options = NULL; |
options = NULL; |
/* |
|
* If our options do not allow this key to be used, |
|
* do not send challenge. |
|
*/ |
|
if (!auth_parse_options(pw, options, linenum)) |
|
continue; |
|
|
|
/* Parse the key from the line. */ |
/* Parse the key from the line. */ |
if (!auth_rsa_read_key(&cp, &bits, pk->e, pk->n)) { |
if (!auth_rsa_read_key(&cp, &bits, pk->e, pk->n)) { |
debug("%.100s, line %lu: bad key syntax", |
debug("%.100s, line %lu: non ssh1 key syntax", |
SSH_USER_PERMITTED_KEYS, linenum); |
file, linenum); |
packet_send_debug("%.100s, line %lu: bad key syntax", |
|
SSH_USER_PERMITTED_KEYS, linenum); |
|
continue; |
continue; |
} |
} |
/* cp now points to the comment part. */ |
/* cp now points to the comment part. */ |
|
|
|
|
/* check the real bits */ |
/* check the real bits */ |
if (bits != BN_num_bits(pk->n)) |
if (bits != BN_num_bits(pk->n)) |
log("Warning: %s, line %ld: keysize mismatch: " |
log("Warning: %s, line %lu: keysize mismatch: " |
"actual %d vs. announced %d.", |
"actual %d vs. announced %d.", |
file, linenum, BN_num_bits(pk->n), bits); |
file, linenum, BN_num_bits(pk->n), bits); |
|
|
/* We have found the desired key. */ |
/* 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; |
|
|
/* Perform the challenge-response dialog for this key. */ |
/* Perform the challenge-response dialog for this key. */ |
if (!auth_rsa_challenge_dialog(pk)) { |
if (!auth_rsa_challenge_dialog(pk)) { |
|
|
restore_uid(); |
restore_uid(); |
|
|
/* Close the file. */ |
/* Close the file. */ |
|
xfree(file); |
fclose(f); |
fclose(f); |
|
|
RSA_free(pk); |
RSA_free(pk); |