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#include <ctype.h>
#include <libconfig.h>
#include <libssh/libssh.h>
#include <uthash.h>
#include "config.h"
#include "data_for_config.h"
struct key {
const char *name; // key
ssh_key key;
UT_hash_handle hh; // makes this structure hashable
};
struct user {
const char *name; // key for hh_user
const char *pubkeystr; // key for hh_pubkey
UT_hash_handle hh_user, hh_pubkey; // makes this structure hashable, twice
};
struct host {
const char *name;
const char *address;
const char *user;
ssh_key key;
const char *pubkeystr;
UT_hash_handle hh; // makes this structure hashable
};
struct key * keys = NULL;
struct user * users = NULL;
struct user * pubkeys = NULL;
struct host *hosts = NULL;
char // returns 0 if ok, something else otherwise
data_init(const config_t * config)
{
config_setting_t *setting;
const int config_dir_len = strlen(CONFIG_DIR);
// We load the ssh keys in the hastable
setting = config_lookup(config, "hostkeys");
if(setting != NULL) {
int count = config_setting_length(setting);
for(int i = 0; i < count; ++i) {
config_setting_t *elt = config_setting_get_elem(setting, i);
const char *name, *key_path;
if (config_setting_lookup_string(elt, "name", &name) == CONFIG_FALSE) {
fprintf(stderr, "Invalid key entry with no name.\n");
return 1;
}
struct key * tmp;
HASH_FIND_STR(keys, name, tmp);
if (tmp != NULL) {
fprintf(stderr, "Invalid key with duplicate name %s.\n", name);
return 1;
}
if (config_setting_lookup_string(elt, "path", &key_path) == CONFIG_FALSE) {
fprintf(stderr, "Invalid key entry %s with no path.\n", name);
return 1;
}
tmp = malloc(sizeof(struct key));
tmp->name = name;
char * key_realpath = malloc(strlen(key_path) + config_dir_len + 1);
strcpy(key_realpath, CONFIG_DIR);
strcpy(key_realpath + config_dir_len, key_path);
switch(ssh_pki_import_privkey_file(key_realpath, NULL, NULL, NULL, &tmp->key)) {
case SSH_EOF:
fprintf(stderr, "Error importing ssh key from file %s : file doesn't exist or permission denied.\n", key_realpath);
free(key_realpath);
free(tmp);
return 1;
break;
case SSH_ERROR:
fprintf(stderr, "Error importing ssh key from file %s.\n", key_realpath);
free(key_realpath);
free(tmp);
return 1;
break;
case SSH_OK:
break;
}
HASH_ADD_KEYPTR(hh, keys, tmp->name, strlen(tmp->name), tmp);
free(key_realpath);
}
}
// We load the users in the hastable
setting = config_lookup(config, "users");
if(setting != NULL) {
int count = config_setting_length(setting);
for(int i = 0; i < count; ++i) {
config_setting_t *elt = config_setting_get_elem(setting, i);
const char *name, *pubkeystr;
if (config_setting_lookup_string(elt, "name", &name) == CONFIG_FALSE) {
fprintf(stderr, "Invalid user entry with no name.\n");
return 1;
}
unsigned int name_len = strlen(name);
struct user * tmp;
HASH_FIND(hh_user, users, name, name_len, tmp);
if (tmp != NULL) {
fprintf(stderr, "Invalid user with duplicate name %s.\n", name);
return 1;
}
if (config_setting_lookup_string(elt, "public_key", &pubkeystr) == CONFIG_FALSE) {
fprintf(stderr, "Invalid user entry %s with no public_key.\n", name);
return 1;
}
// TODO support other key types
// And find a cleaner way to strip this key header before importing, and store a type flag
char * rsa = "ssh-rsa ";
pubkeystr += strlen(rsa);
unsigned int pubkeystr_len = strlen(pubkeystr);
for (unsigned int i = 0; i < pubkeystr_len; ++i) {
if (isspace(pubkeystr[i]) == 0)
continue;
fprintf(stderr, "Invalid trailing characters in public key for user %s :%s.\n", name, pubkeystr+i);
return 1;
}
HASH_FIND(hh_pubkey, pubkeys, pubkeystr, pubkeystr_len, tmp);
if (tmp != NULL) {
fprintf(stderr, "Invalid user %s with duplicate public_key with %s.\n", name, tmp->name);
return 1;
}
ssh_key tmpkey;
switch(ssh_pki_import_pubkey_base64(pubkeystr, SSH_KEYTYPE_RSA, &tmpkey)) {
case SSH_ERROR:
fprintf(stderr, "Error importing public key for user %s.\n", name);
return 1;
break;
case SSH_OK:
ssh_key_free(tmpkey);
break;
}
tmp = malloc(sizeof(struct user));
tmp->name = name;
tmp->pubkeystr = pubkeystr;
HASH_ADD_KEYPTR(hh_user, users, tmp->name, name_len, tmp);
HASH_ADD_KEYPTR(hh_pubkey, pubkeys, tmp->pubkeystr, pubkeystr_len, tmp);
}
}
// We load the hosts in the hastable
setting = config_lookup(config, "hosts");
if(setting != NULL) {
int count = config_setting_length(setting);
for(int i = 0; i < count; ++i) {
config_setting_t *elt = config_setting_get_elem(setting, i);
const char *name, *address, *user, *hostkey, *pubkeystr;
if (config_setting_lookup_string(elt, "name", &name) == CONFIG_FALSE) {
fprintf(stderr, "Invalid host entry with no name.\n");
return 1;
}
struct host * tmp;
HASH_FIND_STR(hosts, name, tmp);
if (tmp != NULL) {
fprintf(stderr, "Invalid host with duplicate name %s.\n", name);
return 1;
}
if (config_setting_lookup_string(elt, "address", &address) == CONFIG_FALSE) {
fprintf(stderr, "Invalid host entry %s with no address.\n", name);
return 1;
}
if (config_setting_lookup_string(elt, "user", &user) == CONFIG_FALSE) {
fprintf(stderr, "Invalid host entry %s with no user.\n", name);
return 1;
}
if (config_setting_lookup_string(elt, "hostkey", &hostkey) == CONFIG_FALSE) {
fprintf(stderr, "Invalid host entry %s with no ssh_key.\n", name);
return 1;
}
struct key * key;
HASH_FIND_STR(keys, hostkey, key);
if (key == NULL) {
fprintf(stderr, "Host key \"%s\" was not found for host \"%s\".\n", hostkey, name);
return 1;
}
if (config_setting_lookup_string(elt, "public_key", &pubkeystr) == CONFIG_FALSE) {
fprintf(stderr, "Invalid user entry %s with no public_key.\n", name);
return 1;
}
// TODO support other key types
// And find a cleaner way to strip this key header before importing, and store a type flag
char * ecdsa = "ssh-ed25519 ";
pubkeystr += strlen(ecdsa);
unsigned int pubkeystr_len = strlen(pubkeystr);
for (unsigned int i = 0; i < pubkeystr_len; ++i) {
if (isspace(pubkeystr[i]) == 0)
continue;
fprintf(stderr, "Invalid trailing characters in public key for user %s :%s.\n", name, pubkeystr+i);
return 1;
}
ssh_key tmpkey;
switch(ssh_pki_import_pubkey_base64(pubkeystr, SSH_KEYTYPE_ED25519, &tmpkey)) {
case SSH_ERROR:
fprintf(stderr, "Error importing public key for user %s.\n", name);
free(tmp);
return 1;
break;
case SSH_OK:
ssh_key_free(tmpkey);
break;
}
tmp = malloc(sizeof(struct host));
tmp->name = name;
tmp->address = address;
tmp->user = user;
tmp->key = key->key;
tmp->pubkeystr = pubkeystr;
HASH_ADD_KEYPTR(hh, hosts, tmp->name, strlen(tmp->name), tmp);
}
}
return 0;
}
void data_clean(void)
{
struct key *current_key, *tmp_key;
HASH_ITER(hh, keys, current_key, tmp_key) {
HASH_DEL(keys, current_key);
ssh_key_free(current_key->key);
free(current_key);
}
HASH_CLEAR(hh_user, users);
struct user *current_pubkey, *tmp_pubkey;
HASH_ITER(hh_pubkey, pubkeys, current_pubkey, tmp_pubkey) {
HASH_DELETE(hh_pubkey, pubkeys, current_pubkey);
free(current_pubkey);
}
struct host *current_host, *tmp_host;
HASH_ITER(hh, hosts, current_host, tmp_host) {
HASH_DEL(hosts, current_host);
free(current_host);
}
}
const char * // returns NULL if no user found
data_get_username_from_pubkey(ssh_key pubkey)
{
const char *username = NULL;
char *pubkeystr;
if (ssh_pki_export_pubkey_base64(pubkey, &pubkeystr) != SSH_OK) {
fprintf(stderr, "Got invalid public key from auth attempt, this shouldn't happen.\n");
return NULL;
}
unsigned int pubkeystr_len = strlen(pubkeystr);
struct user *tmp;
HASH_FIND(hh_pubkey, pubkeys, pubkeystr, pubkeystr_len, tmp);
if (tmp != NULL) {
username = tmp->name;
}
free(pubkeystr);
return username;
}
struct data_host_info * // returns NULL if no key found, this struct is to be freed from the calling code
data_get_host_info(const char * hostname)
{
struct host * tmp;
HASH_FIND_STR(hosts, hostname, tmp);
if (tmp != NULL) {
struct data_host_info *info = malloc(sizeof(struct data_host_info));
info->address = tmp->address;
info->username = tmp->user;
info->key = tmp->key;
info->pubkey = tmp->pubkeystr;
return info;
}
return NULL;
}
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