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snmp.c
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snmp.c
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/*
* "$Id: snmp.c 6049 2006-10-20 15:07:21Z mike $"
*
* SNMP discovery backend for the Common UNIX Printing System (CUPS).
*
* Copyright 2006 by Easy Software Products, all rights reserved.
*
* These coded instructions, statements, and computer programs are the
* property of Easy Software Products and are protected by Federal
* copyright law. Distribution and use rights are outlined in the file
* "LICENSE" which should have been included with this file. If this
* file is missing or damaged please contact Easy Software Products
* at:
*
* Attn: CUPS Licensing Information
* Easy Software Products
* 44141 Airport View Drive, Suite 204
* Hollywood, Maryland 20636 USA
*
* Voice: (301) 373-9600
* EMail: cups-info@cups.org
* WWW: http://www.cups.org
*
* This file is subject to the Apple OS-Developed Software exception.
*
* Contents:
*
* main() - Discover printers via SNMP.
* add_array() - Add a string to an array.
* add_cache() - Add a cached device...
* alarm_handler() - Handle alarm signals...
* asn1_decode_snmp() - Decode a SNMP packet.
* asn1_debug() - Decode an ASN1-encoded message.
* asn1_encode_snmp() - Encode a SNMP packet.
* asn1_get_integer() - Get an integer value.
* asn1_get_length() - Get a value length.
* asn1_get_oid() - Get an OID value.
* asn1_get_packed() - Get a packed integer value.
* asn1_get_string() - Get a string value.
* asn1_get_type() - Get a value type.
* asn1_set_integer() - Set an integer value.
* asn1_set_length() - Set a value length.
* asn1_set_oid() - Set an OID value.
* asn1_set_packed() - Set a packed integer value.
* asn1_size_integer() - Figure out the number of bytes needed for an
* integer value.
* asn1_size_length() - Figure out the number of bytes needed for a
* length value.
* asn1_size_oid() - Figure out the numebr of bytes needed for an
* OID value.
* asn1_size_packed() - Figure out the number of bytes needed for a
* packed integer value.
* compare_cache() - Compare two cache entries.
* debug_printf() - Display some debugging information.
* do_request() - Do a non-blocking IPP request.
* fix_make_model() - Fix common problems in the make-and-model
* string.
* free_array() - Free an array of strings.
* free_cache() - Free the array of cached devices.
* get_interface_addresses() - Get the broadcast address(es) associated
* with an interface.
* hex_debug() - Output hex debugging data...
* list_device() - List a device we found...
* open_snmp_socket() - Open the SNMP broadcast socket.
* password_cb() - Handle authentication requests.
* probe_device() - Probe a device to discover whether it is a
* printer.
* read_snmp_conf() - Read the snmp.conf file.
* read_snmp_response() - Read and parse a SNMP response...
* run_time() - Return the total running time...
* scan_devices() - Scan for devices using SNMP.
* send_snmp_query() - Send an SNMP query packet.
* try_connect() - Try connecting on a port...
* update_cache() - Update a cached device...
*/
/*
* Include necessary headers.
*/
#include <cups/http-private.h>
#include "backend-private.h"
#include <cups/array.h>
#include <cups/file.h>
/*
* This backend implements SNMP printer discovery. It uses a broadcast-
* based approach to get SNMP response packets from potential printers
* and then interrogates each responder by trying to connect on port
* 631, 9100, and 515.
*
* The current focus is on printers with internal network cards, although
* the code also works with many external print servers as well. Future
* versions will support scanning for vendor-specific SNMP OIDs and the
* new PWG Port Monitor MIB and not just the Host MIB OIDs.
*
* The backend reads the snmp.conf file from the CUPS_SERVERROOT directory
* which can contain comments, blank lines, or any number of the following
* directives:
*
* Address ip-address
* Address @LOCAL
* Address @IF(name)
* Community name
* DebugLevel N
* HostNameLookups on
* HostNameLookups off
*
* The default is to use:
*
* Address @LOCAL
* Community public
* DebugLevel 0
* HostNameLookups off
*
* This backend is known to work with the following network printers and
* print servers:
*
* Axis OfficeBasic, 5400, 5600
* EPSON
* Genicom
* HP JetDirect
* Lexmark
* Sharp
* Tektronix
* Xerox
*
* It does not currently work with:
*
* DLink
* Linksys
* Netgear
* Okidata
*
* (for all of these, they do not support the Host MIB)
*/
/*
* Constants...
*/
#define SNMP_PORT 161 /* SNMP well-known port */
#define SNMP_MAX_OID 64 /* Maximum number of OID numbers */
#define SNMP_MAX_PACKET 1472 /* Maximum size of SNMP packet */
#define SNMP_MAX_STRING 512 /* Maximum size of string */
#define SNMP_VERSION_1 0 /* SNMPv1 */
#define ASN1_END_OF_CONTENTS 0x00 /* End-of-contents */
#define ASN1_BOOLEAN 0x01 /* BOOLEAN */
#define ASN1_INTEGER 0x02 /* INTEGER or ENUMERATION */
#define ASN1_BIT_STRING 0x03 /* BIT STRING */
#define ASN1_OCTET_STRING 0x04 /* OCTET STRING */
#define ASN1_NULL_VALUE 0x05 /* NULL VALUE */
#define ASN1_OID 0x06 /* OBJECT IDENTIFIER */
#define ASN1_SEQUENCE 0x30 /* SEQUENCE */
#define ASN1_GET_REQUEST 0xa0 /* Get-Request-PDU */
#define ASN1_GET_RESPONSE 0xa2 /* Get-Response-PDU */
/*
* Types...
*/
typedef struct snmp_cache_s /**** SNMP scan cache ****/
{
http_addr_t address; /* Address of device */
char *addrname, /* Name of device */
*uri, /* device-uri */
*id, /* device-id */
*make_and_model; /* device-make-and-model */
} snmp_cache_t;
typedef struct snmp_packet_s /**** SNMP packet ****/
{
const char *error; /* Encode/decode error */
int version; /* Version number */
char community[SNMP_MAX_STRING];
/* Community name */
int request_type; /* Request type */
int request_id; /* request-id value */
int error_status; /* error-status value */
int error_index; /* error-index value */
int object_name[SNMP_MAX_OID];
/* object-name value */
int object_type; /* object-value type */
union
{
int boolean; /* Boolean value */
int integer; /* Integer value */
int oid[SNMP_MAX_OID]; /* OID value */
char string[SNMP_MAX_STRING];/* String value */
} object_value; /* object-value value */
} snmp_packet_t;
/*
* Private CUPS API to set the last error...
*/
extern void _cupsSetError(ipp_status_t status, const char *message);
/*
* Local functions...
*/
static char *add_array(cups_array_t *a, const char *s);
static void add_cache(http_addr_t *addr, const char *addrname,
const char *uri, const char *id,
const char *make_and_model);
static void alarm_handler(int sig);
static int asn1_decode_snmp(unsigned char *buffer, size_t len,
snmp_packet_t *packet);
static void asn1_debug(unsigned char *buffer, size_t len,
int indent);
static int asn1_encode_snmp(unsigned char *buffer, size_t len,
snmp_packet_t *packet);
static int asn1_get_integer(unsigned char **buffer,
unsigned char *bufend,
int length);
static int asn1_get_oid(unsigned char **buffer,
unsigned char *bufend,
int length, int *oid, int oidsize);
static int asn1_get_packed(unsigned char **buffer,
unsigned char *bufend);
static char *asn1_get_string(unsigned char **buffer,
unsigned char *bufend,
int length, char *string,
int strsize);
static int asn1_get_length(unsigned char **buffer,
unsigned char *bufend);
static int asn1_get_type(unsigned char **buffer,
unsigned char *bufend);
static void asn1_set_integer(unsigned char **buffer,
int integer);
static void asn1_set_length(unsigned char **buffer,
int length);
static void asn1_set_oid(unsigned char **buffer,
const int *oid);
static void asn1_set_packed(unsigned char **buffer,
int integer);
static int asn1_size_integer(int integer);
static int asn1_size_length(int length);
static int asn1_size_oid(const int *oid);
static int asn1_size_packed(int integer);
static int compare_cache(snmp_cache_t *a, snmp_cache_t *b);
static void debug_printf(const char *format, ...);
static ipp_t *do_request(http_t *http, ipp_t *request,
const char *resource);
static void fix_make_model(char *make_model,
const char *old_make_model,
int make_model_size);
static void free_array(cups_array_t *a);
static void free_cache(void);
static http_addrlist_t *get_interface_addresses(const char *ifname);
static void hex_debug(unsigned char *buffer, size_t len);
static void list_device(snmp_cache_t *cache);
static int open_snmp_socket(void);
static const char *password_cb(const char *prompt);
static void probe_device(snmp_cache_t *device);
static void read_snmp_conf(const char *address);
static void read_snmp_response(int fd);
static double run_time(void);
static void scan_devices(int fd);
static void send_snmp_query(int fd, http_addr_t *addr, int version,
const char *community,
const unsigned request_id,
const int *oid);
static int try_connect(http_addr_t *addr, const char *addrname,
int port);
static void update_cache(snmp_cache_t *device, const char *uri,
const char *id, const char *make_model);
/*
* Local globals...
*/
static cups_array_t *Addresses = NULL;
static cups_array_t *Communities = NULL;
static cups_array_t *Devices = NULL;
static int DebugLevel = 0;
static int DeviceTypeOID[] = { 1, 3, 6, 1, 2, 1, 25, 3,
2, 1, 2, 1, 0 };
static int DeviceDescOID[] = { 1, 3, 6, 1, 2, 1, 25, 3,
2, 1, 3, 1, 0 };
static unsigned DeviceTypeRequest;
static unsigned DeviceDescRequest;
static int HostNameLookups = 0;
static int MaxRunTime = 10;
static struct timeval StartTime;
/*
* 'main()' - Discover printers via SNMP.
*/
int /* O - Exit status */
main(int argc, /* I - Number of command-line arguments (6 or 7) */
char *argv[]) /* I - Command-line arguments */
{
int fd; /* SNMP socket */
#if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
struct sigaction action; /* Actions for POSIX signals */
#endif /* HAVE_SIGACTION && !HAVE_SIGSET */
/*
* Check command-line options...
*/
if (argc > 2)
{
fputs("Usage: snmp [host-or-ip-address]\n", stderr);
return (1);
}
/*
* Set the password callback for IPP operations...
*/
cupsSetPasswordCB(password_cb);
/*
* Catch SIGALRM signals...
*/
#ifdef HAVE_SIGSET
sigset(SIGALRM, alarm_handler);
#elif defined(HAVE_SIGACTION)
memset(&action, 0, sizeof(action));
sigemptyset(&action.sa_mask);
sigaddset(&action.sa_mask, SIGALRM);
action.sa_handler = alarm_handler;
sigaction(SIGALRM, &action, NULL);
#else
signal(SIGALRM, alarm_handler);
#endif /* HAVE_SIGSET */
/*
* Open the SNMP socket...
*/
if ((fd = open_snmp_socket()) < 0)
return (1);
/*
* Read the configuration file and any cache data...
*/
read_snmp_conf(argv[1]);
Devices = cupsArrayNew((cups_array_func_t)compare_cache, NULL);
/*
* Scan for devices...
*/
scan_devices(fd);
/*
* Close, free, and return with no errors...
*/
close(fd);
free_array(Addresses);
free_array(Communities);
free_cache();
return (0);
}
/*
* 'add_array()' - Add a string to an array.
*/
static char * /* O - New string */
add_array(cups_array_t *a, /* I - Array */
const char *s) /* I - String to add */
{
char *dups; /* New string */
dups = strdup(s);
cupsArrayAdd(a, dups);
return (dups);
}
/*
* 'add_cache()' - Add a cached device...
*/
static void
add_cache(http_addr_t *addr, /* I - Device IP address */
const char *addrname, /* I - IP address or name string */
const char *uri, /* I - Device URI */
const char *id, /* I - 1284 device ID */
const char *make_and_model) /* I - Make and model */
{
snmp_cache_t *temp; /* New device entry */
debug_printf("DEBUG: add_cache(addr=%p, addrname=\"%s\", uri=\"%s\", "
"id=\"%s\", make_and_model=\"%s\")\n",
addr, addrname, uri ? uri : "(null)", id ? id : "(null)",
make_and_model ? make_and_model : "(null)");
temp = calloc(1, sizeof(snmp_cache_t));
memcpy(&(temp->address), addr, sizeof(temp->address));
temp->addrname = strdup(addrname);
if (uri)
temp->uri = strdup(uri);
if (id)
temp->id = strdup(id);
if (make_and_model)
temp->make_and_model = strdup(make_and_model);
cupsArrayAdd(Devices, temp);
if (uri)
list_device(temp);
}
/*
* 'alarm_handler()' - Handle alarm signals...
*/
static void
alarm_handler(int sig) /* I - Signal number */
{
/*
* Do nothing...
*/
(void)sig;
#if !defined(HAVE_SIGSET) && !defined(HAVE_SIGACTION)
signal(SIGALRM, alarm_handler);
#endif /* !HAVE_SIGSET && !HAVE_SIGACTION */
if (DebugLevel)
write(2, "DEBUG: ALARM!\n", 14);
}
/*
* 'asn1_decode_snmp()' - Decode a SNMP packet.
*/
static int /* O - 0 on success, -1 on error */
asn1_decode_snmp(unsigned char *buffer, /* I - Buffer */
size_t len, /* I - Size of buffer */
snmp_packet_t *packet) /* I - SNMP packet */
{
unsigned char *bufptr, /* Pointer into the data */
*bufend; /* End of data */
int length; /* Length of value */
/*
* Initialize the decoding...
*/
memset(packet, 0, sizeof(snmp_packet_t));
bufptr = buffer;
bufend = buffer + len;
if (asn1_get_type(&bufptr, bufend) != ASN1_SEQUENCE)
packet->error = "Packet does not start with SEQUENCE";
else if (asn1_get_length(&bufptr, bufend) == 0)
packet->error = "SEQUENCE uses indefinite length";
else if (asn1_get_type(&bufptr, bufend) != ASN1_INTEGER)
packet->error = "No version number";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "Version uses indefinite length";
else if ((packet->version = asn1_get_integer(&bufptr, bufend, length))
!= SNMP_VERSION_1)
packet->error = "Bad SNMP version number";
else if (asn1_get_type(&bufptr, bufend) != ASN1_OCTET_STRING)
packet->error = "No community name";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "Community name uses indefinite length";
else
{
asn1_get_string(&bufptr, bufend, length, packet->community,
sizeof(packet->community));
if ((packet->request_type = asn1_get_type(&bufptr, bufend))
!= ASN1_GET_RESPONSE)
packet->error = "Packet does not contain a Get-Response-PDU";
else if (asn1_get_length(&bufptr, bufend) == 0)
packet->error = "Get-Response-PDU uses indefinite length";
else if (asn1_get_type(&bufptr, bufend) != ASN1_INTEGER)
packet->error = "No request-id";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "request-id uses indefinite length";
else
{
packet->request_id = asn1_get_integer(&bufptr, bufend, length);
if (asn1_get_type(&bufptr, bufend) != ASN1_INTEGER)
packet->error = "No error-status";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "error-status uses indefinite length";
else
{
packet->error_status = asn1_get_integer(&bufptr, bufend, length);
if (asn1_get_type(&bufptr, bufend) != ASN1_INTEGER)
packet->error = "No error-index";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "error-index uses indefinite length";
else
{
packet->error_index = asn1_get_integer(&bufptr, bufend, length);
if (asn1_get_type(&bufptr, bufend) != ASN1_SEQUENCE)
packet->error = "No variable-bindings SEQUENCE";
else if (asn1_get_length(&bufptr, bufend) == 0)
packet->error = "variable-bindings uses indefinite length";
else if (asn1_get_type(&bufptr, bufend) != ASN1_SEQUENCE)
packet->error = "No VarBind SEQUENCE";
else if (asn1_get_length(&bufptr, bufend) == 0)
packet->error = "VarBind uses indefinite length";
else if (asn1_get_type(&bufptr, bufend) != ASN1_OID)
packet->error = "No name OID";
else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
packet->error = "Name OID uses indefinite length";
else
{
asn1_get_oid(&bufptr, bufend, length, packet->object_name,
SNMP_MAX_OID);
packet->object_type = asn1_get_type(&bufptr, bufend);
if ((length = asn1_get_length(&bufptr, bufend)) == 0 &&
packet->object_type != ASN1_NULL_VALUE &&
packet->object_type != ASN1_OCTET_STRING)
packet->error = "Value uses indefinite length";
else
{
switch (packet->object_type)
{
case ASN1_BOOLEAN :
packet->object_value.boolean =
asn1_get_integer(&bufptr, bufend, length);
break;
case ASN1_INTEGER :
packet->object_value.integer =
asn1_get_integer(&bufptr, bufend, length);
break;
case ASN1_NULL_VALUE :
break;
case ASN1_OCTET_STRING :
asn1_get_string(&bufptr, bufend, length,
packet->object_value.string,
SNMP_MAX_STRING);
break;
case ASN1_OID :
asn1_get_oid(&bufptr, bufend, length,
packet->object_value.oid, SNMP_MAX_OID);
break;
default :
packet->error = "Unsupported value type";
break;
}
}
}
}
}
}
}
return (packet->error ? -1 : 0);
}
/*
* 'asn1_debug()' - Decode an ASN1-encoded message.
*/
static void
asn1_debug(unsigned char *buffer, /* I - Buffer */
size_t len, /* I - Length of buffer */
int indent) /* I - Indentation */
{
int i; /* Looping var */
unsigned char *bufend; /* End of buffer */
int integer; /* Number value */
int oid[SNMP_MAX_OID]; /* OID value */
char string[SNMP_MAX_STRING];/* String value */
unsigned char value_type; /* Type of value */
int value_length; /* Length of value */
bufend = buffer + len;
while (buffer < bufend)
{
/*
* Get value type...
*/
value_type = asn1_get_type(&buffer, bufend);
value_length = asn1_get_length(&buffer, bufend);
switch (value_type)
{
case ASN1_BOOLEAN :
integer = asn1_get_integer(&buffer, bufend, value_length);
fprintf(stderr, "DEBUG: %*sBOOLEAN %d bytes %d\n", indent, "",
value_length, integer);
break;
case ASN1_INTEGER :
integer = asn1_get_integer(&buffer, bufend, value_length);
fprintf(stderr, "DEBUG: %*sINTEGER %d bytes %d\n", indent, "",
value_length, integer);
break;
case ASN1_OCTET_STRING :
fprintf(stderr, "DEBUG: %*sOCTET STRING %d bytes \"%s\"\n", indent, "",
value_length, asn1_get_string(&buffer, bufend,
value_length, string,
sizeof(string)));
break;
case ASN1_NULL_VALUE :
fprintf(stderr, "DEBUG: %*sNULL VALUE %d bytes\n", indent, "",
value_length);
buffer += value_length;
break;
case ASN1_OID :
asn1_get_oid(&buffer, bufend, value_length, oid, SNMP_MAX_OID);
fprintf(stderr, "DEBUG: %*sOID %d bytes ", indent, "",
value_length);
for (i = 0; oid[i]; i ++)
fprintf(stderr, ".%d", oid[i]);
putc('\n', stderr);
break;
case ASN1_SEQUENCE :
fprintf(stderr, "DEBUG: %*sSEQUENCE %d bytes\n", indent, "",
value_length);
asn1_debug(buffer, value_length, indent + 4);
buffer += value_length;
break;
case ASN1_GET_REQUEST :
fprintf(stderr, "DEBUG: %*sGet-Request-PDU %d bytes\n", indent, "",
value_length);
asn1_debug(buffer, value_length, indent + 4);
buffer += value_length;
break;
case ASN1_GET_RESPONSE :
fprintf(stderr, "DEBUG: %*sGet-Response-PDU %d bytes\n", indent, "",
value_length);
asn1_debug(buffer, value_length, indent + 4);
buffer += value_length;
break;
default :
fprintf(stderr, "DEBUG: %*sUNKNOWN(%x) %d bytes\n", indent, "",
value_type, value_length);
buffer += value_length;
break;
}
}
}
/*
* 'asn1_encode_snmp()' - Encode a SNMP packet.
*/
static int /* O - Length on success, -1 on error */
asn1_encode_snmp(unsigned char *buffer, /* I - Buffer */
size_t bufsize, /* I - Size of buffer */
snmp_packet_t *packet) /* I - SNMP packet */
{
unsigned char *bufptr; /* Pointer into buffer */
int total, /* Total length */
msglen, /* Length of entire message */
commlen, /* Length of community string */
reqlen, /* Length of request */
listlen, /* Length of variable list */
varlen, /* Length of variable */
namelen, /* Length of object name OID */
valuelen; /* Length of object value */
/*
* Get the lengths of the community string, OID, and message...
*/
namelen = asn1_size_oid(packet->object_name);
switch (packet->object_type)
{
case ASN1_NULL_VALUE :
valuelen = 0;
break;
case ASN1_BOOLEAN :
valuelen = asn1_size_integer(packet->object_value.boolean);
break;
case ASN1_INTEGER :
valuelen = asn1_size_integer(packet->object_value.integer);
break;
case ASN1_OCTET_STRING :
valuelen = strlen(packet->object_value.string);
break;
case ASN1_OID :
valuelen = asn1_size_oid(packet->object_value.oid);
break;
default :
packet->error = "Unknown object type";
return (-1);
}
varlen = 1 + asn1_size_length(namelen) + namelen +
1 + asn1_size_length(valuelen) + valuelen;
listlen = 1 + asn1_size_length(varlen) + varlen;
reqlen = 2 + asn1_size_integer(packet->request_id) +
2 + asn1_size_integer(packet->error_status) +
2 + asn1_size_integer(packet->error_index) +
1 + asn1_size_length(listlen) + listlen;
commlen = strlen(packet->community);
msglen = 2 + asn1_size_integer(packet->version) +
1 + asn1_size_length(commlen) + commlen +
1 + asn1_size_length(reqlen) + reqlen;
total = 1 + asn1_size_length(msglen) + msglen;
if (total > bufsize)
{
packet->error = "Message too large for buffer";
return (-1);
}
/*
* Then format the message...
*/
bufptr = buffer;
*bufptr++ = ASN1_SEQUENCE; /* SNMPv1 message header */
asn1_set_length(&bufptr, msglen);
asn1_set_integer(&bufptr, packet->version);
/* version */
*bufptr++ = ASN1_OCTET_STRING; /* community */
asn1_set_length(&bufptr, commlen);
memcpy(bufptr, packet->community, commlen);
bufptr += commlen;
*bufptr++ = packet->request_type; /* Get-Request-PDU */
asn1_set_length(&bufptr, reqlen);
asn1_set_integer(&bufptr, packet->request_id);
asn1_set_integer(&bufptr, packet->error_status);
asn1_set_integer(&bufptr, packet->error_index);
*bufptr++ = ASN1_SEQUENCE; /* variable-bindings */
asn1_set_length(&bufptr, listlen);
*bufptr++ = ASN1_SEQUENCE; /* variable */
asn1_set_length(&bufptr, varlen);
asn1_set_oid(&bufptr, packet->object_name);
/* ObjectName */
switch (packet->object_type)
{
case ASN1_NULL_VALUE :
*bufptr++ = ASN1_NULL_VALUE; /* ObjectValue */
*bufptr++ = 0; /* Length */
break;
case ASN1_BOOLEAN :
asn1_set_integer(&bufptr, packet->object_value.boolean);
break;
case ASN1_INTEGER :
asn1_set_integer(&bufptr, packet->object_value.integer);
break;
case ASN1_OCTET_STRING :
*bufptr++ = ASN1_OCTET_STRING;
asn1_set_length(&bufptr, valuelen);
memcpy(bufptr, packet->object_value.string, valuelen);
bufptr += valuelen;
break;
case ASN1_OID :
asn1_set_oid(&bufptr, packet->object_value.oid);
break;
}
return (bufptr - buffer);
}
/*
* 'asn1_get_integer()' - Get an integer value.
*/
static int /* O - Integer value */
asn1_get_integer(
unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend, /* I - End of buffer */
int length) /* I - Length of value */
{
int value; /* Integer value */
for (value = 0;
length > 0 && *buffer < bufend;
length --, (*buffer) ++)
value = (value << 8) | **buffer;
return (value);
}
/*
* 'asn1_get_length()' - Get a value length.
*/
static int /* O - Length */
asn1_get_length(unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend) /* I - End of buffer */
{
int length; /* Length */
length = **buffer;
(*buffer) ++;
if (length & 128)
length = asn1_get_integer(buffer, bufend, length & 127);
return (length);
}
/*
* 'asn1_get_oid()' - Get an OID value.
*/
static int /* O - Last OID number */
asn1_get_oid(
unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend, /* I - End of buffer */
int length, /* I - Length of value */
int *oid, /* I - OID buffer */
int oidsize) /* I - Size of OID buffer */
{
unsigned char *valend; /* End of value */
int *oidend; /* End of OID buffer */
int number; /* OID number */
valend = *buffer + length;
oidend = oid + oidsize - 1;
if (valend > bufend)
valend = bufend;
number = asn1_get_packed(buffer, bufend);
if (number < 80)
{
*oid++ = number / 40;
number = number % 40;
*oid++ = number;
}
else
{
*oid++ = 2;
number -= 80;
*oid++ = number;
}
while (*buffer < valend)
{
number = asn1_get_packed(buffer, bufend);
if (oid < oidend)
*oid++ = number;
}
*oid = 0;
return (number);
}
/*
* 'asn1_get_packed()' - Get a packed integer value.
*/
static int /* O - Value */
asn1_get_packed(
unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend) /* I - End of buffer */
{
int value; /* Value */
value = 0;
while ((**buffer & 128) && *buffer < bufend)
{
value = (value << 7) | (**buffer & 127);
(*buffer) ++;
}
if (*buffer < bufend)
{
value = (value << 7) | **buffer;
(*buffer) ++;
}
return (value);
}
/*
* 'asn1_get_string()' - Get a string value.
*/
static char * /* O - String */
asn1_get_string(
unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend, /* I - End of buffer */
int length, /* I - Value length */
char *string, /* I - String buffer */
int strsize) /* I - String buffer size */
{
if (length < strsize)
{
memcpy(string, *buffer, length);
string[length] = '\0';
}
else
{
memcpy(string, buffer, strsize - 1);
string[strsize - 1] = '\0';
}
(*buffer) += length;
return (string);
}
/*
* 'asn1_get_type()' - Get a value type.
*/
static int /* O - Type */
asn1_get_type(unsigned char **buffer, /* IO - Pointer in buffer */
unsigned char *bufend) /* I - End of buffer */
{
int type; /* Type */