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config_init.c
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config_init.c
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/**
******************************************************************************
*
* \file config_init.c
*
* \brief Command-line and config file processing for fwknop client.
*
* Fwknop is developed primarily by the people listed in the file 'AUTHORS'.
* Copyright (C) 2009-2014 fwknop developers and contributors. For a full
* list of contributors, see the file 'CREDITS'.
*
* License (GNU General Public License):
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
******************************************************************************
*/
#include "fwknop_common.h"
#include "netinet_common.h"
#include "config_init.h"
#include "cmd_opts.h"
#include "utils.h"
#include <sys/stat.h>
#include <fcntl.h>
#ifdef WIN32
#define STDIN_FILENO 0
#endif
#define RC_PARAM_TEMPLATE "%-24s %s\n" /*!< Template to define param = val in a rc file */
#define RC_SECTION_DEFAULT "default" /*!< Name of the default section in fwknoprc */
#define RC_SECTION_TEMPLATE "[%s]\n" /*!< Template to define a section in a rc file */
#define FWKNOPRC_OFLAGS (O_WRONLY|O_CREAT|O_EXCL) /*!< O_flags used to create an fwknoprc file with the open function */
#define FWKNOPRC_MODE (S_IRUSR|S_IWUSR) /*!< mode used to create an fwknoprc file with the open function */
#define PARAM_YES_VALUE "Y" /*!< String which represents a YES value for a parameter in fwknoprc */
#define PARAM_NO_VALUE "N" /*!< String which represents a NO value for a parameter in fwknoprc */
#define POSITION_TO_BITMASK(x) ((uint32_t)(1) << ((x) % 32)) /*!< Macro do get a bitmask from a position */
#define BITMASK_ARRAY_SIZE 2 /*!< Number of 32bits integer used to handle bitmask in the fko_var_bitmask_t structure */
#define LF_CHAR 0x0A /*!< Hexadecimal value associated to the LF char */
#ifdef HAVE_C_UNIT_TESTS
#include "cunit_common.h"
DECLARE_TEST_SUITE(config_init, "Config init test suite");
#endif
/**
* Structure to handle long bitmask.
*
* The structure is built as an array of unsigned 32 bits integer to be able to
* easily increase the size of the bitmask.
* This bitmask can contains at most (BITMASK_ARRAY_SIZE * 32) values.
*/
typedef struct fko_var_bitmask
{
uint32_t dw[BITMASK_ARRAY_SIZE]; /*!< Array of bitmasks */
} fko_var_bitmask_t;
/**
* Structure to handle a variable in an rcfile (name and value)
*/
typedef struct rc_file_param
{
char name[MAX_LINE_LEN]; /*!< Variable name */
char val[MAX_LINE_LEN]; /*!< Variable value */
} rc_file_param_t;
/**
* Structure to identify a configuration variable (name and position)
*/
typedef struct fko_var
{
const char name[32]; /*!< Variable name in fwknoprc */
unsigned int pos; /*!< Variable position from the fwknop_cli_arg_t enumeration */
} fko_var_t;
enum
{
FWKNOP_CLI_FIRST_ARG = 0,
FWKNOP_CLI_ARG_DIGEST_TYPE = 0,
FWKNOP_CLI_ARG_SPA_SERVER_PROTO,
FWKNOP_CLI_ARG_SPA_SERVER_PORT,
FWKNOP_CLI_ARG_SPA_SOURCE_PORT,
FWKNOP_CLI_ARG_FW_TIMEOUT,
FWKNOP_CLI_ARG_ALLOW_IP,
FWKNOP_CLI_ARG_TIME_OFFSET,
FWKNOP_CLI_ARG_ENCRYPTION_MODE,
FWKNOP_CLI_ARG_USE_GPG,
FWKNOP_CLI_ARG_USE_GPG_AGENT,
FWKNOP_CLI_ARG_GPG_NO_SIGNING_PW,
FWKNOP_CLI_ARG_GPG_RECIPIENT,
FWKNOP_CLI_ARG_GPG_SIGNER,
FWKNOP_CLI_ARG_GPG_HOMEDIR,
FWKNOP_CLI_ARG_GPG_EXE_PATH,
FWKNOP_CLI_ARG_SPOOF_USER,
FWKNOP_CLI_ARG_SPOOF_SOURCE_IP,
FWKNOP_CLI_ARG_ACCESS,
FWKNOP_CLI_ARG_SPA_SERVER,
FWKNOP_CLI_ARG_RAND_PORT,
FWKNOP_CLI_ARG_KEY_RIJNDAEL,
FWKNOP_CLI_ARG_KEY_RIJNDAEL_BASE64,
FWKNOP_CLI_ARG_GPG_SIGNING_PW,
FWKNOP_CLI_ARG_GPG_SIGNING_PW_BASE64,
FWKNOP_CLI_ARG_HMAC_DIGEST_TYPE,
FWKNOP_CLI_ARG_KEY_HMAC_BASE64,
FWKNOP_CLI_ARG_KEY_HMAC,
FWKNOP_CLI_ARG_USE_HMAC,
FWKNOP_CLI_ARG_USE_WGET_USER_AGENT,
FWKNOP_CLI_ARG_KEY_FILE,
FWKNOP_CLI_ARG_HMAC_KEY_FILE,
FWKNOP_CLI_ARG_NAT_ACCESS,
FWKNOP_CLI_ARG_HTTP_USER_AGENT,
FWKNOP_CLI_ARG_RESOLVE_URL,
FWKNOP_CLI_ARG_SERVER_RESOLVE_IPV4,
FWKNOP_CLI_ARG_NAT_LOCAL,
FWKNOP_CLI_ARG_NAT_RAND_PORT,
FWKNOP_CLI_ARG_NAT_PORT,
FWKNOP_CLI_ARG_VERBOSE,
FWKNOP_CLI_ARG_RESOLVE_IP_HTTP,
FWKNOP_CLI_ARG_RESOLVE_IP_HTTPS,
FWKNOP_CLI_ARG_RESOLVE_HTTP_ONLY,
FWKNOP_CLI_ARG_WGET_CMD,
FWKNOP_CLI_ARG_NO_SAVE_ARGS,
FWKNOP_CLI_LAST_ARG
} fwknop_cli_arg_t;
static fko_var_t fko_var_array[FWKNOP_CLI_LAST_ARG] =
{
{ "DIGEST_TYPE", FWKNOP_CLI_ARG_DIGEST_TYPE },
{ "SPA_SERVER_PROTO", FWKNOP_CLI_ARG_SPA_SERVER_PROTO },
{ "SPA_SERVER_PORT", FWKNOP_CLI_ARG_SPA_SERVER_PORT },
{ "SPA_SOURCE_PORT", FWKNOP_CLI_ARG_SPA_SOURCE_PORT },
{ "FW_TIMEOUT", FWKNOP_CLI_ARG_FW_TIMEOUT },
{ "ALLOW_IP", FWKNOP_CLI_ARG_ALLOW_IP },
{ "TIME_OFFSET", FWKNOP_CLI_ARG_TIME_OFFSET },
{ "ENCRYPTION_MODE", FWKNOP_CLI_ARG_ENCRYPTION_MODE },
{ "USE_GPG", FWKNOP_CLI_ARG_USE_GPG },
{ "USE_GPG_AGENT", FWKNOP_CLI_ARG_USE_GPG_AGENT },
{ "GPG_RECIPIENT", FWKNOP_CLI_ARG_GPG_RECIPIENT },
{ "GPG_SIGNER", FWKNOP_CLI_ARG_GPG_SIGNER },
{ "GPG_HOMEDIR", FWKNOP_CLI_ARG_GPG_HOMEDIR },
{ "GPG_EXE", FWKNOP_CLI_ARG_GPG_EXE_PATH },
{ "GPG_SIGNING_PW", FWKNOP_CLI_ARG_GPG_SIGNING_PW },
{ "GPG_SIGNING_PW_BASE64", FWKNOP_CLI_ARG_GPG_SIGNING_PW_BASE64 },
{ "GPG_NO_SIGNING_PW", FWKNOP_CLI_ARG_GPG_NO_SIGNING_PW },
{ "SPOOF_USER", FWKNOP_CLI_ARG_SPOOF_USER },
{ "SPOOF_SOURCE_IP", FWKNOP_CLI_ARG_SPOOF_SOURCE_IP },
{ "ACCESS", FWKNOP_CLI_ARG_ACCESS },
{ "SPA_SERVER", FWKNOP_CLI_ARG_SPA_SERVER },
{ "RAND_PORT", FWKNOP_CLI_ARG_RAND_PORT },
{ "KEY", FWKNOP_CLI_ARG_KEY_RIJNDAEL },
{ "KEY_BASE64", FWKNOP_CLI_ARG_KEY_RIJNDAEL_BASE64 },
{ "HMAC_DIGEST_TYPE", FWKNOP_CLI_ARG_HMAC_DIGEST_TYPE },
{ "HMAC_KEY_BASE64", FWKNOP_CLI_ARG_KEY_HMAC_BASE64 },
{ "HMAC_KEY", FWKNOP_CLI_ARG_KEY_HMAC },
{ "USE_HMAC", FWKNOP_CLI_ARG_USE_HMAC },
{ "USE_WGET_USER_AGENT", FWKNOP_CLI_ARG_USE_WGET_USER_AGENT },
{ "KEY_FILE", FWKNOP_CLI_ARG_KEY_FILE },
{ "HMAC_KEY_FILE", FWKNOP_CLI_ARG_HMAC_KEY_FILE },
{ "NAT_ACCESS", FWKNOP_CLI_ARG_NAT_ACCESS },
{ "HTTP_USER_AGENT", FWKNOP_CLI_ARG_HTTP_USER_AGENT },
{ "RESOLVE_URL", FWKNOP_CLI_ARG_RESOLVE_URL },
{ "SERVER_RESOLVE_IPV4", FWKNOP_CLI_ARG_SERVER_RESOLVE_IPV4 },
{ "NAT_LOCAL", FWKNOP_CLI_ARG_NAT_LOCAL },
{ "NAT_RAND_PORT", FWKNOP_CLI_ARG_NAT_RAND_PORT },
{ "NAT_PORT", FWKNOP_CLI_ARG_NAT_PORT },
{ "VERBOSE", FWKNOP_CLI_ARG_VERBOSE },
{ "RESOLVE_IP_HTTP", FWKNOP_CLI_ARG_RESOLVE_IP_HTTP },
{ "RESOLVE_IP_HTTPS", FWKNOP_CLI_ARG_RESOLVE_IP_HTTPS },
{ "RESOLVE_HTTP_ONLY", FWKNOP_CLI_ARG_RESOLVE_HTTP_ONLY },
{ "WGET_CMD", FWKNOP_CLI_ARG_WGET_CMD },
{ "NO_SAVE_ARGS", FWKNOP_CLI_ARG_NO_SAVE_ARGS }
};
/* Array to define which conf. variables are critical and should not be
* overwritten when a stanza is updated using the --save-rc-stanza arg
* without the user validation */
static int critical_var_array[] =
{
FWKNOP_CLI_ARG_KEY_RIJNDAEL,
FWKNOP_CLI_ARG_KEY_RIJNDAEL_BASE64,
FWKNOP_CLI_ARG_KEY_HMAC,
FWKNOP_CLI_ARG_KEY_HMAC_BASE64,
FWKNOP_CLI_ARG_GPG_RECIPIENT,
FWKNOP_CLI_ARG_GPG_SIGNER,
FWKNOP_CLI_ARG_GPG_SIGNING_PW,
FWKNOP_CLI_ARG_GPG_SIGNING_PW_BASE64
};
/**
* @brief Generate Rijndael + HMAC keys from /dev/urandom (base64 encoded).
*
* @param options FKO command line option structure
*/
static void
generate_keys(fko_cli_options_t *options)
{
int res;
/* If asked, we have to generate the keys */
if(options->key_gen)
{
/* Zero out the key buffers */
memset(&(options->key_base64), 0x00, sizeof(options->key_base64));
memset(&(options->hmac_key_base64), 0x00, sizeof(options->hmac_key_base64));
/* Generate the key through libfko */
res = fko_key_gen(options->key_base64, options->key_len,
options->hmac_key_base64, options->hmac_key_len,
options->hmac_type);
/* Exit upon key generation failure*/
if(res != FKO_SUCCESS)
{
log_msg(LOG_VERBOSITY_ERROR, "%s: fko_key_gen: Error %i - %s",
MY_NAME, res, fko_errstr(res));
exit(EXIT_FAILURE);
}
/* Everything is ok - nothing to do */
else;
}
/* No key generation asked - nothing to do */
else;
}
/**
* @brief Check if a variable is a critical var.
*
* This function check the critical_var_array table to find if the variable
* position is available.
*
* @param var_pos Fwknop configuration variable position
*
* @return 1 the variable is critical, 0 otherwise
*/
static int
var_is_critical(short var_pos)
{
int ndx; /* Index on the critical_var_array array */
int var_found = 0;
/* Go through the array of critical vars */
for (ndx=0 ; ndx<ARRAY_SIZE(critical_var_array) ; ndx++)
{
/* and check if we find it */
if (var_pos == critical_var_array[ndx])
{
var_found = 1;
break;
}
}
return var_found;
}
/**
* @brief Add a variable to a bitmask
*
* This function adds the bitmask associated to a variable position, to a
* bitmask.
*
* @param var_pos Fwknop configuration variable position
* @param bm fko_var_bitmask_t variable to update
*/
static void
add_var_to_bitmask(short var_pos, fko_var_bitmask_t *bm)
{
unsigned int bitmask_ndx;
/* Look for the index on the uint32_t array we have to process */
bitmask_ndx = var_pos / 32;
/* Set the bitmask according to the index found */
if (bitmask_ndx < BITMASK_ARRAY_SIZE)
bm->dw[bitmask_ndx] |= POSITION_TO_BITMASK(var_pos);
/* The index on the uint32_t bitmask is invalid */
else
log_msg(LOG_VERBOSITY_WARNING,
"add_var_to_bitmask() : Bad variable position %u", var_pos);
}
/**
* @brief Remove a variable from a bitmask
*
* This function removes the bitmask associated to the variable position from a
* bitmask.
*
* @param var_pos Fwknop configuration variable position
* @param bm fko_var_bitmask_t structure to update
*/
static void
remove_var_from_bitmask(short var_pos, fko_var_bitmask_t *bm)
{
unsigned int bitmask_ndx;
/* Look for the index on the uint32_t array we have to process */
bitmask_ndx = var_pos / 32;
/* Set the bitmask according to the index found */
if (bitmask_ndx < BITMASK_ARRAY_SIZE)
bm->dw[bitmask_ndx] &= ~POSITION_TO_BITMASK(var_pos);
/* The index on the uint32_t bitmask is invalid */
else
log_msg(LOG_VERBOSITY_WARNING,
"remove_from_bitmask() : Bad variable position %u", var_pos);
}
/**
* @brief Return whether a variable is available in a bitmask
*
* The variable bitmask is looked for in the bitmask.
*
* @param var_pos Fwknop configuration variable position
* @param bm fko_var_bitmask_t structure to check
*
* @return 1 if the bitmsk contains the variable, 0 otherwise.
*/
static int
bitmask_has_var(short var_pos, fko_var_bitmask_t *bm)
{
unsigned int bitmask_ndx;
int var_found = 0;
/* Look for the index on the uint32_t array we have to process */
bitmask_ndx = var_pos / 32;
/* Check the bitmask according to the index found */
if (bitmask_ndx < BITMASK_ARRAY_SIZE)
{
if ( bm->dw[bitmask_ndx] & POSITION_TO_BITMASK(var_pos) )
var_found = 1;
}
/* The index on the uint32_t bitmask is invalid */
else
log_msg(LOG_VERBOSITY_WARNING, "bitmask_has_var_ndx() : Bad variable position %u", var_pos);
return var_found;
}
/**
* @brief Ask the user if a variable must be overwritten or not for a specific stanza
*
* If the user sets other chars than a 'y' char, we assume he does not want to
* overwrite the variable.
*
* @param var Variable which should be overwritten
* @param stanza Stanza where the variable should be overwritten
*
* @return 1 if the user wants to overwrite the variable, 0 otherwise
*/
static int
ask_overwrite_var(const char *var, const char *stanza)
{
char user_input = 'N';
int overwrite = 0;
int c;
int first_char = 1;;
log_msg(LOG_VERBOSITY_NORMAL,
"Variable '%s' found in stanza '%s'. Overwrite [N/y] ? ",
var, stanza);
while ((c=getchar()) != LF_CHAR)
{
if (first_char)
user_input = c;
first_char = 0;
}
if (user_input == 'y')
overwrite = 1;
return overwrite;
}
/**
* @brief Lookup a variable in the variable array according to its name
*
* This function parses the fko_var_array table and try to find a match
* for the user string, which indicates we have found a configuration variable.
*
* @param str String to compare against every fwknop conf variables
*
* @return A pointer on the variable structure, or NULL if not found
*/
static fko_var_t *
lookup_var_by_name(const char *var_name)
{
short ndx; /* Index on the the fko_var_array table */
fko_var_t *var = NULL;
/* Check str against each variable available in fko_var_array */
for (ndx=0 ; ndx<ARRAY_SIZE(fko_var_array) ; ndx++)
{
if (CONF_VAR_IS(var_name, fko_var_array[ndx].name))
{
var = &(fko_var_array[ndx]);
break;
}
}
return var;
}
/**
* @brief Lookup a variable in the variable array according to its position
*
* This function parses the fko_var_array table and try to find a match
* for the position, which indicates we have found a configuration variable.
*
* @param var_pos Position to compare against every fwknop conf variables
*
* @return A pointer on the variable structure, or NULL if not found
*/
static fko_var_t *
lookup_var_by_position(short var_pos)
{
short ndx; /* Index on the the fko_var_array table */
fko_var_t *var = NULL;
/* Check str against each variable available in fko_var_array */
for (ndx=0 ; ndx<ARRAY_SIZE(fko_var_array) ; ndx++)
{
if (var_pos == fko_var_array[ndx].pos)
{
var = &(fko_var_array[ndx]);
break;
}
}
return var;
}
/**
* @brief Set a string as a Yes or No value according to a boolean (0 or 1).
*
* This function checks whether a value is set to zero or not, and updates a
* string to a YES_NO parameter value.
* The string must be zeroed before being passed to the function.
*
* @param val Variable to check
* @param s String where to store the YES_NO value.
* @param len Number of bytes avaialble for the s buffer.
*/
static void
bool_to_yesno(int val, char* s, size_t len)
{
if (val == 0)
strlcpy(s, PARAM_NO_VALUE, len);
else
strlcpy(s, PARAM_YES_VALUE, len);
}
/**
* @brief Is a string formatted as YES string.
*
* @param s String to check for a YES string
*
* @return 1 if the string match the YES pattern, 0 otherwise
*/
static int
is_yes_str(const char *s)
{
int valid;
if (strcasecmp(PARAM_YES_VALUE, s) == 0)
valid = 1;
else
valid = 0;
return valid;
}
/**
* @brief Check if a section is in a line and fetch it.
*
* This function parses a NULL terminated string in order to find a section,
* something like [mysection]. If it succeeds, the stanza is retrieved.
*
* @param line String containing a line from the rc file to check for a section
* @param line_size size of the line buffer
* @param rc_section String to store the section found
* @param rc_section_size Size of the rc_section buffer
*
* @return 1 if a section was found, 0 otherwise
*/
static int
is_rc_section(const char* line, uint16_t line_size, char* rc_section, uint16_t rc_section_size)
{
char *ndx, *emark;
char buf[MAX_LINE_LEN] = {0};
int section_found = 0;
if (line_size < sizeof(buf))
{
strlcpy(buf, line, sizeof(buf));
ndx = buf;
while(isspace(*ndx))
ndx++;
if(*ndx == '[')
{
ndx++;
emark = strchr(ndx, ']');
if(emark != NULL)
{
*emark = '\0';
memset(rc_section, 0, rc_section_size);
strlcpy(rc_section, ndx, rc_section_size);
section_found = 1;
}
else
{
}
}
}
else
{
}
return section_found;
}
/**
* @brief Grab a variable and its value from a rc line.
*
* @param line Line to parse for a variable
* @param param Parameter structure where to store the variable name and its value
*
* @return 0 if no variable has been found, 1 otherwise.
*/
static int
is_rc_param(const char *line, rc_file_param_t *param)
{
char var[MAX_LINE_LEN] = {0};
char val[MAX_LINE_LEN] = {0};
char *ndx;
memset(param, 0, sizeof(*param));
/* Fetch the variable and its value */
if(sscanf(line, "%s %[^ ;\t\n\r#]", var, val) != 2)
{
log_msg(LOG_VERBOSITY_WARNING,
"*Invalid entry in '%s'", line);
return 0;
}
/* Remove any colon that may be on the end of the var */
if((ndx = strrchr(var, ':')) != NULL)
*ndx = '\0';
/* Even though sscanf should automatically add a terminating
* NULL byte, an assumption is made that the input arrays are
* big enough, so we'll force a terminating NULL byte regardless
*/
var[MAX_LINE_LEN-1] = 0x0;
val[MAX_LINE_LEN-1] = 0x0;
/* Copy back the val and var in the structure */
strlcpy(param->name, var, sizeof(param->name));
strlcpy(param->val, val, sizeof(param->val));
return 1;
}
/**
* @brief Dump available stanzas from a fwknoprc file
*
* This function parses a rcfile and looks for configured stanzas.
* They are all displayed except the default stanza.
*
* @param rcfile full path to the rcfile to parse
*/
static int
dump_configured_stanzas_from_rcfile(const char* rcfile)
{
FILE *rc;
char line[MAX_LINE_LEN] = {0};
char curr_stanza[MAX_LINE_LEN] = {0};
/* Open the rcfile in read mode */
if ((rc = fopen(rcfile, "r")) == NULL)
{
log_msg(LOG_VERBOSITY_WARNING, "Unable to open rc file: %s: %s",
rcfile, strerror(errno));
return EXIT_FAILURE;
}
log_msg(LOG_VERBOSITY_NORMAL, "The following stanzas are configured in %s :", rcfile);
/* Parse the rcfile line by line to find stanza */
while ((fgets(line, MAX_LINE_LEN, rc)) != NULL)
{
line[MAX_LINE_LEN-1] = '\0';
/* Get past comments and empty lines (note: we only look at the first
* character. */
if(IS_EMPTY_LINE(line[0]))
continue;
/* Check which section we are working on */
else if (is_rc_section(line, strlen(line), curr_stanza, sizeof(curr_stanza)))
{
/* Print the stanza and continue - we exclude the default stanza */
if (strcasecmp(curr_stanza, RC_SECTION_DEFAULT) != 0)
log_msg(LOG_VERBOSITY_NORMAL, " - %s", curr_stanza);
continue;
}
/* Nothing we care about */
else;
}
fclose(rc);
return EXIT_SUCCESS;
}
/* Assign path to fwknop rc file
*/
static void
set_rc_file(char *rcfile, fko_cli_options_t *options)
{
int rcf_offset;
char *homedir;
memset(rcfile, 0x0, MAX_PATH_LEN);
if(options->rc_file[0] == 0x0)
{
#ifdef WIN32
homedir = getenv("USERPROFILE");
#else
homedir = getenv("HOME");
#endif
if(homedir == NULL)
{
log_msg(LOG_VERBOSITY_ERROR, "Warning: Unable to determine HOME directory.\n"
" No .fwknoprc file processed.");
exit(EXIT_FAILURE);
}
strlcpy(rcfile, homedir, MAX_PATH_LEN);
rcf_offset = strlen(rcfile);
/* Sanity check the path to .fwknoprc.
* The preceeding path plus the path separator and '.fwknoprc' = 11
* cannot exceed MAX_PATH_LEN.
*/
if(rcf_offset > (MAX_PATH_LEN - 11))
{
log_msg(LOG_VERBOSITY_ERROR, "Warning: Path to .fwknoprc file is too long.\n"
" No .fwknoprc file processed.");
exit(EXIT_FAILURE);
}
rcfile[rcf_offset] = PATH_SEP;
strlcat(rcfile, ".fwknoprc", MAX_PATH_LEN);
}
else
{
strlcpy(rcfile, options->rc_file, MAX_PATH_LEN);
}
/* Check rc file permissions - if anything other than user read/write,
* then throw a warning. This change was made to help ensure that the
* client consumes a proper rc file with strict permissions set (thanks
* to Fernando Arnaboldi from IOActive for pointing this out).
*/
if(verify_file_perms_ownership(rcfile) != 1)
exit(EXIT_FAILURE);
return;
}
static void
keys_status(fko_cli_options_t *options)
{
FILE *key_gen_file_ptr = NULL;
char rcfile[MAX_PATH_LEN] = {0};
if(options->key_gen == 1)
{
if(options->key_gen_file[0] != '\0')
{
if ((key_gen_file_ptr = fopen(options->key_gen_file, "w")) == NULL)
{
log_msg(LOG_VERBOSITY_ERROR, "Unable to create key gen file: %s: %s",
options->key_gen_file, strerror(errno));
exit(EXIT_FAILURE);
}
fprintf(key_gen_file_ptr, "KEY_BASE64: %s\nHMAC_KEY_BASE64: %s\n",
options->key_base64, options->hmac_key_base64);
fclose(key_gen_file_ptr);
log_msg(LOG_VERBOSITY_NORMAL,
"[+] Wrote Rijndael and HMAC keys to: %s",
options->key_gen_file);
}
else
{
if(options->save_rc_stanza == 1)
{
set_rc_file(rcfile, options);
log_msg(LOG_VERBOSITY_NORMAL,
"[+] Wrote Rijndael and HMAC keys to rc file: %s", rcfile);
}
else
log_msg(LOG_VERBOSITY_NORMAL,
"KEY_BASE64: %s\nHMAC_KEY_BASE64: %s",
options->key_base64, options->hmac_key_base64);
}
/* Always exit out in --key-gen mode since the fwknopd server
* has no way to know what the new keys are
*/
exit(EXIT_SUCCESS);
}
}
/* Parse any time offset from the command line
*/
static int
parse_time_offset(const char *offset_str, int *offset)
{
int i, j;
int offset_type = TIME_OFFSET_SECONDS;
int os_len = strlen(offset_str);
int is_err = 0;
char offset_digits[MAX_TIME_STR_LEN] = {0};
j=0;
for (i=0; i < os_len; i++) {
if (isdigit(offset_str[i])) {
offset_digits[j] = offset_str[i];
j++;
if(j >= MAX_TIME_STR_LEN)
{
return 0;
}
} else if (offset_str[i] == 'm' || offset_str[i] == 'M') {
offset_type = TIME_OFFSET_MINUTES;
break;
} else if (offset_str[i] == 'h' || offset_str[i] == 'H') {
offset_type = TIME_OFFSET_HOURS;
break;
} else if (offset_str[i] == 'd' || offset_str[i] == 'D') {
offset_type = TIME_OFFSET_DAYS;
break;
}
}
offset_digits[j] = '\0';
if (j < 1)
return 0;
*offset = strtol_wrapper(offset_digits, 0, (2 << 15),
NO_EXIT_UPON_ERR, &is_err);
/* Apply the offset_type multiplier
*/
*offset *= offset_type;
return is_err == 0 ? 1 : 0;
}
static int
create_fwknoprc(const char *rcfile)
{
FILE *rc = NULL;
int rcfile_fd = -1;
log_msg(LOG_VERBOSITY_NORMAL, "[*] Creating initial rc file: %s.", rcfile);
/* Try to create the initial rcfile with user read/write rights only.
* If the rcfile already exists, an error is returned */
rcfile_fd = open(rcfile, FWKNOPRC_OFLAGS ,FWKNOPRC_MODE);
// If an error occured ...
if (rcfile_fd == -1) {
log_msg(LOG_VERBOSITY_WARNING, "Unable to create initial rc file: %s: %s",
rcfile, strerror(errno));
return(-1);
}
// Free the rcfile descriptor
close(rcfile_fd);
if ((rc = fopen(rcfile, "w")) == NULL)
{
log_msg(LOG_VERBOSITY_WARNING, "Unable to write default setup to rcfile: %s: %s",
rcfile, strerror(errno));
return(-1);
}
fprintf(rc,
"# .fwknoprc\n"
"##############################################################################\n"
"#\n"
"# Firewall Knock Operator (fwknop) client rc file.\n"
"#\n"
"# This file contains user-specific fwknop client configuration default\n"
"# and named parameter sets for specific invocations of the fwknop client.\n"
"#\n"
"# Each section (or stanza) is identified and started by a line in this\n"
"# file that contains a single identifier surrounded by square brackets.\n"
"# It is this identifier (or name) that is used from the fwknop command line\n"
"# via the '-n <name>' argument to reference the corresponding stanza.\n"
"#\n"
"# The parameters within the stanza typically match corresponding client \n"
"# command-line parameters.\n"
"#\n"
"# The first one should always be `[default]' as it defines the global\n"
"# default settings for the user. These override the program defaults\n"
"# for these parameters. If a named stanza is used, its entries will\n"
"# override any of the default values. Command-line options will trump them\n"
"# all.\n"
"#\n"
"# Subsequent stanzas will have only the overriding and destination\n"
"# specific parameters.\n"
"#\n"
"# Lines starting with `#' and empty lines are ignored.\n"
"#\n"
"# See the fwknop.8 man page for a complete list of valid parameters\n"
"# and their values.\n"
"#\n"
"##############################################################################\n"
"#\n"
"# We start with the 'default' stanza. Uncomment and edit for your\n"
"# preferences. The client will use its built-in default for those items\n"
"# that are commented out.\n"
"#\n"
"[default]\n"
"\n"
"#DIGEST_TYPE sha256\n"
"#FW_TIMEOUT 30\n"
"#SPA_SERVER_PORT 62201\n"
"#SPA_SERVER_PROTO udp\n"
"#ALLOW_IP <ip addr>\n"
"#SPOOF_USER <username>\n"
"#SPOOF_SOURCE_IP <IPaddr>\n"
"#TIME_OFFSET 0\n"
"#USE_GPG N\n"
"#GPG_HOMEDIR /path/to/.gnupg\n"
"#GPG_EXE /path/to/gpg\n"
"#GPG_SIGNER <signer ID>\n"
"#GPG_RECIPIENT <recipient ID>\n"
"#NO_SAVE_ARGS N\n"
"\n"
"# User-provided named stanzas:\n"
"\n"
"# Example for a destination server of 192.168.1.20 to open access to\n"
"# SSH for an IP that is resolved externally, and one with a NAT request\n"
"# for a specific source IP that maps port 8088 on the server\n"
"# to port 88 on 192.168.1.55 with timeout.\n"
"#\n"
"#[myssh]\n"
"#SPA_SERVER 192.168.1.20\n"
"#ACCESS tcp/22\n"
"#ALLOW_IP resolve\n"
"#\n"
"#[mynatreq]\n"
"#SPA_SERVER 192.168.1.20\n"
"#ACCESS tcp/8088\n"
"#ALLOW_IP 10.21.2.6\n"
"#NAT_ACCESS 192.168.1.55,88\n"
"#CLIENT_TIMEOUT 60\n"
"#\n"
"\n"
);
fclose(rc);
return(0);
}
static int
parse_rc_param(fko_cli_options_t *options, const char *var_name, char * val)
{
int tmpint, is_err;
int parse_error = 0; /* 0 if the variable has been successfully processed, < 0 otherwise */
fko_var_t *var; /* Pointer on an fwknop variable structure */
log_msg(LOG_VERBOSITY_DEBUG, "parse_rc_param() : Parsing variable %s...", var_name);
/* Lookup the variable according to its name. */
var = lookup_var_by_name(var_name);
/* The variable is not handled if its pointer is NULL */
if (var == NULL)
parse_error = -1;
/* Digest Type */
else if (var->pos == FWKNOP_CLI_ARG_DIGEST_TYPE)
{
tmpint = digest_strtoint(val);
if(tmpint < 0)
parse_error = -1;
else
options->digest_type = tmpint;
}
/* Server protocol */
else if (var->pos == FWKNOP_CLI_ARG_SPA_SERVER_PROTO)
{
tmpint = proto_strtoint(val);
if(tmpint < 0)
parse_error = -1;
else
options->spa_proto = tmpint;
}
/* Server port */
else if (var->pos == FWKNOP_CLI_ARG_SPA_SERVER_PORT)
{
tmpint = strtol_wrapper(val, 0, MAX_PORT, NO_EXIT_UPON_ERR, &is_err);
if(is_err == FKO_SUCCESS)
options->spa_dst_port = tmpint;
else
parse_error = -1;
}
/* Source port */
else if (var->pos == FWKNOP_CLI_ARG_SPA_SOURCE_PORT)
{
tmpint = strtol_wrapper(val, 0, MAX_PORT, NO_EXIT_UPON_ERR, &is_err);
if(is_err == FKO_SUCCESS)
options->spa_src_port = tmpint;
else
parse_error = -1;
}
/* Firewall rule timeout */
else if (var->pos == FWKNOP_CLI_ARG_FW_TIMEOUT)
{
tmpint = strtol_wrapper(val, 0, (2 << 15), NO_EXIT_UPON_ERR, &is_err);
if(is_err == FKO_SUCCESS)
options->fw_timeout = tmpint;
else
parse_error = -1;
}
/* Allow IP */
else if (var->pos == FWKNOP_CLI_ARG_ALLOW_IP)
{
/* In case this was set previously
*/
options->resolve_ip_http_https = 0;
/* use source, resolve, or an actual IP
*/
if(strcasecmp(val, "source") == 0)
strlcpy(options->allow_ip_str, "0.0.0.0", sizeof(options->allow_ip_str));
else if(strcasecmp(val, "resolve") == 0)
options->resolve_ip_http_https = 1;
else /* Assume IP address and validate */
{
strlcpy(options->allow_ip_str, val, sizeof(options->allow_ip_str));
if(! is_valid_ipv4_addr(options->allow_ip_str))
parse_error = -1;
}
}
/* Time Offset */
else if (var->pos == FWKNOP_CLI_ARG_TIME_OFFSET)
{
if(val[0] == '-')
{
val++;
if(! parse_time_offset(val, &options->time_offset_minus))
parse_error = -1;
}
else
if (! parse_time_offset(val, &options->time_offset_plus))
parse_error = -1;
if(parse_error == -1)
log_msg(LOG_VERBOSITY_WARNING,
"TIME_OFFSET argument '%s' invalid.", val);
}