version 1.119.2.3, 2003/04/03 22:35:18 |
version 1.120, 2002/05/23 19:24:30 |
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char *client_version_string = NULL; |
char *client_version_string = NULL; |
char *server_version_string = NULL; |
char *server_version_string = NULL; |
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/* import */ |
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extern Options options; |
extern Options options; |
extern char *__progname; |
extern char *__progname; |
extern uid_t original_real_uid; |
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extern uid_t original_effective_uid; |
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extern pid_t proxy_command_pid; |
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static int show_other_keys(const char *, Key *); |
static const char * |
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sockaddr_ntop(struct sockaddr *sa) |
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{ |
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void *addr; |
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static char addrbuf[INET6_ADDRSTRLEN]; |
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switch (sa->sa_family) { |
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case AF_INET: |
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addr = &((struct sockaddr_in *)sa)->sin_addr; |
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break; |
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case AF_INET6: |
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addr = &((struct sockaddr_in6 *)sa)->sin6_addr; |
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break; |
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default: |
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/* This case should be protected against elsewhere */ |
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abort(); /* XXX abort is bad -- do something else */ |
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} |
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inet_ntop(sa->sa_family, addr, addrbuf, sizeof(addrbuf)); |
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return addrbuf; |
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} |
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/* |
/* |
* Connect to the given ssh server using a proxy command. |
* Connect to the given ssh server using a proxy command. |
*/ |
*/ |
static int |
static int |
ssh_proxy_connect(const char *host, u_short port, const char *proxy_command) |
ssh_proxy_connect(const char *host, u_short port, struct passwd *pw, |
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const char *proxy_command) |
{ |
{ |
Buffer command; |
Buffer command; |
const char *cp; |
const char *cp; |
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/* Convert the port number into a string. */ |
/* Convert the port number into a string. */ |
snprintf(strport, sizeof strport, "%hu", port); |
snprintf(strport, sizeof strport, "%hu", port); |
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/* |
/* Build the final command string in the buffer by making the |
* Build the final command string in the buffer by making the |
appropriate substitutions to the given proxy command. */ |
* appropriate substitutions to the given proxy command. |
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* |
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* Use "exec" to avoid "sh -c" processes on some platforms |
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* (e.g. Solaris) |
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*/ |
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buffer_init(&command); |
buffer_init(&command); |
buffer_append(&command, "exec ", 5); |
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for (cp = proxy_command; *cp; cp++) { |
for (cp = proxy_command; *cp; cp++) { |
if (cp[0] == '%' && cp[1] == '%') { |
if (cp[0] == '%' && cp[1] == '%') { |
buffer_append(&command, "%", 1); |
buffer_append(&command, "%", 1); |
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char *argv[10]; |
char *argv[10]; |
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/* Child. Permanently give up superuser privileges. */ |
/* Child. Permanently give up superuser privileges. */ |
seteuid(original_real_uid); |
permanently_set_uid(pw); |
setuid(original_real_uid); |
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/* Redirect stdin and stdout. */ |
/* Redirect stdin and stdout. */ |
close(pin[1]); |
close(pin[1]); |
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/* Parent. */ |
/* Parent. */ |
if (pid < 0) |
if (pid < 0) |
fatal("fork failed: %.100s", strerror(errno)); |
fatal("fork failed: %.100s", strerror(errno)); |
else |
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proxy_command_pid = pid; /* save pid to clean up later */ |
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/* Close child side of the descriptors. */ |
/* Close child side of the descriptors. */ |
close(pin[0]); |
close(pin[0]); |
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* Creates a (possibly privileged) socket for use as the ssh connection. |
* Creates a (possibly privileged) socket for use as the ssh connection. |
*/ |
*/ |
static int |
static int |
ssh_create_socket(int privileged, int family) |
ssh_create_socket(struct passwd *pw, int privileged, int family) |
{ |
{ |
int sock, gaierr; |
int sock, gaierr; |
struct addrinfo hints, *res; |
struct addrinfo hints, *res; |
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*/ |
*/ |
if (privileged) { |
if (privileged) { |
int p = IPPORT_RESERVED - 1; |
int p = IPPORT_RESERVED - 1; |
PRIV_START; |
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sock = rresvport_af(&p, family); |
sock = rresvport_af(&p, family); |
PRIV_END; |
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if (sock < 0) |
if (sock < 0) |
error("rresvport: af=%d %.100s", family, strerror(errno)); |
error("rresvport: af=%d %.100s", family, strerror(errno)); |
else |
else |
debug("Allocated local port %d.", p); |
debug("Allocated local port %d.", p); |
return sock; |
return sock; |
} |
} |
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/* |
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* Just create an ordinary socket on arbitrary port. We use |
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* the user's uid to create the socket. |
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*/ |
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temporarily_use_uid(pw); |
sock = socket(family, SOCK_STREAM, 0); |
sock = socket(family, SOCK_STREAM, 0); |
if (sock < 0) |
if (sock < 0) |
error("socket: %.100s", strerror(errno)); |
error("socket: %.100s", strerror(errno)); |
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restore_uid(); |
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/* Bind the socket to an alternative local IP address */ |
/* Bind the socket to an alternative local IP address */ |
if (options.bind_address == NULL) |
if (options.bind_address == NULL) |
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/* |
/* |
* Opens a TCP/IP connection to the remote server on the given host. |
* Opens a TCP/IP connection to the remote server on the given host. |
* The address of the remote host will be returned in hostaddr. |
* The address of the remote host will be returned in hostaddr. |
* If port is 0, the default port will be used. If needpriv is true, |
* If port is 0, the default port will be used. If anonymous is zero, |
* a privileged port will be allocated to make the connection. |
* a privileged port will be allocated to make the connection. |
* This requires super-user privileges if needpriv is true. |
* This requires super-user privileges if anonymous is false. |
* Connection_attempts specifies the maximum number of tries (one per |
* Connection_attempts specifies the maximum number of tries (one per |
* second). If proxy_command is non-NULL, it specifies the command (with %h |
* second). If proxy_command is non-NULL, it specifies the command (with %h |
* and %p substituted for host and port, respectively) to use to contact |
* and %p substituted for host and port, respectively) to use to contact |
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int |
int |
ssh_connect(const char *host, struct sockaddr_storage * hostaddr, |
ssh_connect(const char *host, struct sockaddr_storage * hostaddr, |
u_short port, int family, int connection_attempts, |
u_short port, int family, int connection_attempts, |
int needpriv, const char *proxy_command) |
int anonymous, struct passwd *pw, const char *proxy_command) |
{ |
{ |
int gaierr; |
int gaierr; |
int on = 1; |
int on = 1; |
int sock = -1, attempt; |
int sock = -1, attempt; |
char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
struct addrinfo hints, *ai, *aitop; |
struct addrinfo hints, *ai, *aitop; |
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struct linger linger; |
struct servent *sp; |
struct servent *sp; |
/* |
/* |
* Did we get only other errors than "Connection refused" (which |
* Did we get only other errors than "Connection refused" (which |
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*/ |
*/ |
int full_failure = 1; |
int full_failure = 1; |
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debug2("ssh_connect: needpriv %d", needpriv); |
debug("ssh_connect: getuid %u geteuid %u anon %d", |
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(u_int) getuid(), (u_int) geteuid(), anonymous); |
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/* Get default port if port has not been set. */ |
/* Get default port if port has not been set. */ |
if (port == 0) { |
if (port == 0) { |
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} |
} |
/* If a proxy command is given, connect using it. */ |
/* If a proxy command is given, connect using it. */ |
if (proxy_command != NULL) |
if (proxy_command != NULL) |
return ssh_proxy_connect(host, port, proxy_command); |
return ssh_proxy_connect(host, port, pw, proxy_command); |
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/* No proxy command. */ |
/* No proxy command. */ |
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memset(&hints, 0, sizeof(hints)); |
memset(&hints, 0, sizeof(hints)); |
hints.ai_family = family; |
hints.ai_family = family; |
hints.ai_socktype = SOCK_STREAM; |
hints.ai_socktype = SOCK_STREAM; |
snprintf(strport, sizeof strport, "%u", port); |
snprintf(strport, sizeof strport, "%d", port); |
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) |
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) |
fatal("%s: %.100s: %s", __progname, host, |
fatal("%s: %.100s: %s", __progname, host, |
gai_strerror(gaierr)); |
gai_strerror(gaierr)); |
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host, ntop, strport); |
host, ntop, strport); |
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/* Create a socket for connecting. */ |
/* Create a socket for connecting. */ |
sock = ssh_create_socket(needpriv, ai->ai_family); |
sock = ssh_create_socket(pw, |
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!anonymous && geteuid() == 0, |
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ai->ai_family); |
if (sock < 0) |
if (sock < 0) |
/* Any error is already output */ |
/* Any error is already output */ |
continue; |
continue; |
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/* Connect to the host. We use the user's uid in the |
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* hope that it will help with tcp_wrappers showing |
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* the remote uid as root. |
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*/ |
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temporarily_use_uid(pw); |
if (connect(sock, ai->ai_addr, ai->ai_addrlen) >= 0) { |
if (connect(sock, ai->ai_addr, ai->ai_addrlen) >= 0) { |
/* Successful connection. */ |
/* Successful connection. */ |
memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
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restore_uid(); |
break; |
break; |
} else { |
} else { |
if (errno == ECONNREFUSED) |
if (errno == ECONNREFUSED) |
full_failure = 0; |
full_failure = 0; |
debug("connect to address %s port %s: %s", |
log("ssh: connect to address %s port %s: %s", |
ntop, strport, strerror(errno)); |
sockaddr_ntop(ai->ai_addr), strport, |
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strerror(errno)); |
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restore_uid(); |
/* |
/* |
* Close the failed socket; there appear to |
* Close the failed socket; there appear to |
* be some problems when reusing a socket for |
* be some problems when reusing a socket for |
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freeaddrinfo(aitop); |
freeaddrinfo(aitop); |
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/* Return failure if we didn't get a successful connection. */ |
/* Return failure if we didn't get a successful connection. */ |
if (attempt >= connection_attempts) { |
if (attempt >= connection_attempts) |
log("ssh: connect to host %s port %s: %s", |
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host, strport, strerror(errno)); |
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return full_failure ? ECONNABORTED : ECONNREFUSED; |
return full_failure ? ECONNABORTED : ECONNREFUSED; |
} |
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debug("Connection established."); |
debug("Connection established."); |
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/* |
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* Set socket options. We would like the socket to disappear as soon |
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* as it has been closed for whatever reason. |
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*/ |
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/* setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); */ |
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linger.l_onoff = 1; |
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linger.l_linger = 5; |
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setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); |
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/* Set keepalives if requested. */ |
/* Set keepalives if requested. */ |
if (options.keepalives && |
if (options.keepalives && |
setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
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(p[0] == '\0') || (p[0] == '\n') || |
(p[0] == '\0') || (p[0] == '\n') || |
strncasecmp(p, "no", 2) == 0) |
strncasecmp(p, "no", 2) == 0) |
ret = 0; |
ret = 0; |
if (p && strncasecmp(p, "yes", 3) == 0) |
if (strncasecmp(p, "yes", 3) == 0) |
ret = 1; |
ret = 1; |
if (p) |
if (p) |
xfree(p); |
xfree(p); |
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* check whether the supplied host key is valid, return -1 if the key |
* check whether the supplied host key is valid, return -1 if the key |
* is not valid. the user_hostfile will not be updated if 'readonly' is true. |
* is not valid. the user_hostfile will not be updated if 'readonly' is true. |
*/ |
*/ |
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static int |
static int |
check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key, |
check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key, |
int readonly, const char *user_hostfile, const char *system_hostfile) |
int readonly, const char *user_hostfile, const char *system_hostfile) |
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int local = 0, host_ip_differ = 0; |
int local = 0, host_ip_differ = 0; |
char ntop[NI_MAXHOST]; |
char ntop[NI_MAXHOST]; |
char msg[1024]; |
char msg[1024]; |
int len, host_line, ip_line, has_keys; |
int len, host_line, ip_line; |
const char *host_file = NULL, *ip_file = NULL; |
const char *host_file = NULL, *ip_file = NULL; |
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/* |
/* |
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"have requested strict checking.", type, host); |
"have requested strict checking.", type, host); |
goto fail; |
goto fail; |
} else if (options.strict_host_key_checking == 2) { |
} else if (options.strict_host_key_checking == 2) { |
has_keys = show_other_keys(host, host_key); |
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/* The default */ |
/* The default */ |
fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
snprintf(msg, sizeof(msg), |
snprintf(msg, sizeof(msg), |
"The authenticity of host '%.200s (%s)' can't be " |
"The authenticity of host '%.200s (%s)' can't be " |
"established%s\n" |
"established.\n" |
"%s key fingerprint is %s.\n" |
"%s key fingerprint is %s.\n" |
"Are you sure you want to continue connecting " |
"Are you sure you want to continue connecting " |
"(yes/no)? ", |
"(yes/no)? ", host, ip, type, fp); |
host, ip, |
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has_keys ? ",\nbut keys of different type are already " |
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"known for this host." : ".", |
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type, fp); |
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xfree(fp); |
xfree(fp); |
if (!confirm(msg)) |
if (!confirm(msg)) |
goto fail; |
goto fail; |
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* accept the authentication. |
* accept the authentication. |
*/ |
*/ |
break; |
break; |
case HOST_FOUND: |
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fatal("internal error"); |
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break; |
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} |
} |
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if (options.check_host_ip && host_status != HOST_CHANGED && |
if (options.check_host_ip && host_status != HOST_CHANGED && |
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len = strlen(msg); |
len = strlen(msg); |
snprintf(msg + len, sizeof(msg) - len, |
snprintf(msg + len, sizeof(msg) - len, |
"\nMatching host key in %s:%d", |
"\nMatching host key in %s:%d", |
host_file, host_line); |
host_file, host_line); |
} |
} |
if (options.strict_host_key_checking == 1) { |
if (options.strict_host_key_checking == 1) { |
log(msg); |
log(msg); |
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packet_put_string(padded, size); |
packet_put_string(padded, size); |
memset(padded, 0, size); |
memset(padded, 0, size); |
xfree(padded); |
xfree(padded); |
} |
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static int |
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show_key_from_file(const char *file, const char *host, int keytype) |
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{ |
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Key *found; |
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char *fp; |
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int line, ret; |
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found = key_new(keytype); |
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if ((ret = lookup_key_in_hostfile_by_type(file, host, |
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keytype, found, &line))) { |
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fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX); |
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log("WARNING: %s key found for host %s\n" |
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"in %s:%d\n" |
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"%s key fingerprint %s.", |
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key_type(found), host, file, line, |
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key_type(found), fp); |
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xfree(fp); |
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} |
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key_free(found); |
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return (ret); |
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} |
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/* print all known host keys for a given host, but skip keys of given type */ |
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static int |
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show_other_keys(const char *host, Key *key) |
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{ |
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int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1}; |
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int i, found = 0; |
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for (i = 0; type[i] != -1; i++) { |
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if (type[i] == key->type) |
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continue; |
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if (type[i] != KEY_RSA1 && |
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show_key_from_file(options.user_hostfile2, host, type[i])) { |
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found = 1; |
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continue; |
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} |
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if (type[i] != KEY_RSA1 && |
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show_key_from_file(options.system_hostfile2, host, type[i])) { |
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found = 1; |
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continue; |
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} |
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if (show_key_from_file(options.user_hostfile, host, type[i])) { |
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found = 1; |
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continue; |
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} |
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if (show_key_from_file(options.system_hostfile, host, type[i])) { |
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found = 1; |
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continue; |
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} |
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debug2("no key of type %d for host %s", type[i], host); |
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} |
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return (found); |
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} |
} |