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-rw-r--r--Source/charon/asn1/asn1.c34
-rw-r--r--Source/charon/asn1/asn1.h86
-rw-r--r--Source/charon/asn1/der_decoder.c395
-rw-r--r--Source/charon/asn1/der_decoder.h22
4 files changed, 449 insertions, 88 deletions
diff --git a/Source/charon/asn1/asn1.c b/Source/charon/asn1/asn1.c
index cbd030bb5..01952386c 100644
--- a/Source/charon/asn1/asn1.c
+++ b/Source/charon/asn1/asn1.c
@@ -1,21 +1,33 @@
+/**
+ * @file asn1.c
+ *
+ * @brief String mappings for asn1.h
+ *
+ */
-
-
-
-
+/*
+ * Copyright (C) 2006 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
#include "asn1.h"
-
-
-
-
mapping_t asn1_type_m[] = {
{ASN1_END, "ASN1_END"},
{ASN1_BOOLEAN, "ASN1_BOOLEAN"},
{ASN1_INTEGER, "ASN1_INTEGER"},
- {ASN1_BIT_STRING, "ASN1_BIT_STRING"},
- {ASN1_OCTET_STRING, "ASN1_OCTET_STRING"},
+ {ASN1_BITSTRING, "ASN1_BITSTRING"},
+ {ASN1_OCTETSTRING, "ASN1_OCTETSTRING"},
{ASN1_NULL, "ASN1_NULL"},
{ASN1_OID, "ASN1_OID"},
{ASN1_ENUMERATED, "ASN1_ENUMERATED"},
@@ -43,6 +55,7 @@ mapping_t asn1_type_m[] = {
{ASN1_TAG_E_5, "ASN1_TAG_E_5"},
{ASN1_TAG_E_6, "ASN1_TAG_E_6"},
{ASN1_TAG_E_7, "ASN1_TAG_E_7"},
+ {ASN1_TAG_I_0, "ASN1_TAG_I_0"},
{ASN1_TAG_I_1, "ASN1_TAG_I_1"},
{ASN1_TAG_I_2, "ASN1_TAG_I_2"},
{ASN1_TAG_I_3, "ASN1_TAG_I_3"},
@@ -50,6 +63,7 @@ mapping_t asn1_type_m[] = {
{ASN1_TAG_I_5, "ASN1_TAG_I_5"},
{ASN1_TAG_I_6, "ASN1_TAG_I_6"},
{ASN1_TAG_I_7, "ASN1_TAG_I_7"},
+ {ASN1_CHOICE, "ASN1_CHOICE"},
};
mapping_t asn1_flag_m[] = {
diff --git a/Source/charon/asn1/asn1.h b/Source/charon/asn1/asn1.h
index a828034ee..894f048d2 100644
--- a/Source/charon/asn1/asn1.h
+++ b/Source/charon/asn1/asn1.h
@@ -1,7 +1,7 @@
/**
* @file asn1.h
*
- * @brief Definition of asn1_type_t and asn1_rule_t.
+ * @brief Definition of asn1_rule_t and other ASN1 stuff.
*
*/
@@ -27,12 +27,20 @@
typedef enum asn1_type_t asn1_type_t;
+/**
+ * @brief Real and some special ASN1 types.
+ *
+ * @ingroup asn1
+ */
enum asn1_type_t {
+ /**
+ * End of a sequence, set, choice
+ */
ASN1_END = 0x00,
ASN1_BOOLEAN = 0x01,
ASN1_INTEGER = 0x02,
- ASN1_BIT_STRING = 0x03,
- ASN1_OCTET_STRING = 0x04,
+ ASN1_BITSTRING = 0x03,
+ ASN1_OCTETSTRING = 0x04,
ASN1_NULL = 0x05,
ASN1_OID = 0x06,
ASN1_ENUMERATED = 0x0A,
@@ -52,6 +60,9 @@ enum asn1_type_t {
ASN1_CONSTRUCTED = 0x20,
ASN1_SEQUENCE = 0x30,
ASN1_SET = 0x31,
+ /**
+ * EXCPLICIT tags
+ */
ASN1_TAG_E_0 = 0xA0,
ASN1_TAG_E_1 = 0xA1,
ASN1_TAG_E_2 = 0xA2,
@@ -60,6 +71,10 @@ enum asn1_type_t {
ASN1_TAG_E_5 = 0xA5,
ASN1_TAG_E_6 = 0xA6,
ASN1_TAG_E_7 = 0xA7,
+ /**
+ * IMPLICIT tags
+ */
+ ASN1_TAG_I_0 = 0x80,
ASN1_TAG_I_1 = 0x81,
ASN1_TAG_I_2 = 0x82,
ASN1_TAG_I_3 = 0x83,
@@ -67,24 +82,70 @@ enum asn1_type_t {
ASN1_TAG_I_5 = 0x85,
ASN1_TAG_I_6 = 0x86,
ASN1_TAG_I_7 = 0x87,
+ /**
+ * Begin of a choice
+ */
+ ASN1_CHOICE = 0xFE,
+ /**
+ * ANY type
+ */
+ ASN1_ANY = 0xFF,
};
+/**
+ * String mappings for asn1_type_t
+ */
extern mapping_t asn1_type_m[];
+
typedef enum asn1_flag_t asn1_flag_t;
+/**
+ * @brief Flags used to build ASN1 rules.
+ *
+ * @ingroup asn1
+ */
enum asn1_flag_t {
+ /**
+ * Field is optional
+ */
ASN1_OPTIONAL = 0x01,
+ /**
+ * Field has a default value and is therefore optional
+ */
ASN1_DEFAULT = 0x02,
+ /**
+ * Convert this INTEGER to an mpz_t
+ */
ASN1_MPZ = 0x04,
+ /**
+ * SEQUENCE or SET OF
+ */
ASN1_OF = 0x08,
+ /**
+ * Parse this Sequence in a RAW chunk too.
+ * Used for crypto calculations...
+ */
+ ASN1_RAW = 0x10,
};
+/**
+ * String mappings for asn1_flag_t
+ */
extern mapping_t asn1_flag_m[];
typedef struct asn1_rule_t asn1_rule_t;
+/**
+ * @brief Single rule of a complet ruleset.
+ *
+ * This rule containing a type, flags and additional
+ * data allow modellation of complex ASN1 structures and
+ * allow their en- and decoding...
+ *
+ * @ingroup asn1
+ */
struct asn1_rule_t {
/**
* ASN1 type
@@ -98,18 +159,13 @@ struct asn1_rule_t {
* offset of data in structure
*/
u_int data_offset;
-// union {
- /**
- * offset to a boolean, which says if optional
- * data is available at data_offset. Used if
- * flags & ASN1_OPTIONAL.
- */
-// u_int available_offset;
- /**
- * default value, used if flags & ASN1_DEFAULT
- */
- u_int default_value;
-// };
+ /**
+ * offset to a boolean, which says if optional
+ * data is available at data_offset. Used if
+ * flags & ASN1_OPTIONAL.
+ * default value, used if flags & ASN1_DEFAULT
+ */
+ u_int additional;
};
diff --git a/Source/charon/asn1/der_decoder.c b/Source/charon/asn1/der_decoder.c
index 59ea4b077..91521b96a 100644
--- a/Source/charon/asn1/der_decoder.c
+++ b/Source/charon/asn1/der_decoder.c
@@ -5,9 +5,12 @@
*/
/*
- * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Copyright (C) 2000-2004 Andreas Steffen
+ * Copyright (C) 2006 Martin Willi
* Hochschule fuer Technik Rapperswil
*
+ * Some parts taken over from pluto/asn1.c
+ *
* 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
@@ -39,56 +42,269 @@ struct private_der_decoder_t {
*/
der_decoder_t public;
+ /**
+ * Rule which was just processed
+ */
asn1_rule_t *rule;
+ /**
+ * First rule of the hole ruleset
+ */
asn1_rule_t *first_rule;
+ /**
+ * Output data struct
+ */
void *output;
+ /**
+ * Complex things like this need a logger ;-)
+ */
logger_t *logger;
};
status_t read_hdr(private_der_decoder_t *this, chunk_t *data);
+/**
+ * Read a sequence from data, parse its contents recursivly
+ */
status_t read_sequence(private_der_decoder_t *this, chunk_t data)
{
- while (this->rule->type != ASN1_END)
+ status_t status;
+ asn1_rule_t *next_rule;
+
+ while(TRUE)
{
- read_hdr(this, &data);
+ next_rule = this->rule + 1;
+ if (next_rule->type == ASN1_END)
+ {
+ this->rule++;
+ break;
+ }
+ status = read_hdr(this, &data);
+ if (status != SUCCESS)
+ {
+ return status;
+ }
}
+
+ this->logger->log(this->logger, CONTROL|LEVEL2, "Sequence end");
return SUCCESS;
}
+/**
+ * Read choice of data, parse if one of the choosable types arise
+ */
+status_t read_choice(private_der_decoder_t *this, chunk_t *data)
+{
+ status_t status = PARSE_ERROR;
+ asn1_rule_t *next_rule;
+ bool found = FALSE;
+
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "Choice data", *data);
+
+ while(TRUE)
+ {
+ next_rule = this->rule + 1;
+ if (next_rule->type == ASN1_END)
+ {
+ this->rule++;
+ return status;
+ }
+ if (!found && *(data->ptr) == next_rule->type)
+ {
+ found = TRUE;
+ status = read_hdr(this, data);
+ }
+ else
+ {
+ this->rule++;
+ }
+ }
+ this->logger->log(this->logger, CONTROL|LEVEL2, "Choice end");
+ return status;
+}
+/**
+ * Read a utc or generalized time
+ */
+status_t read_time(private_der_decoder_t *this, chunk_t data)
+{
+ struct tm t;
+ time_t tz_offset;
+ u_char *eot = NULL;
+ const char* format;
+ time_t *result = (time_t*)((u_int8_t*)this->output + this->rule->data_offset);
+
+ /* TODO: Test it */
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "TIME", data);
+
+ if ((eot = memchr(data.ptr, 'Z', data.len)) != NULL)
+ {
+ /* Zulu time with a zero time zone offset */
+ tz_offset = 0;
+ }
+ else if ((eot = memchr(data.ptr, '+', data.len)) != NULL)
+ {
+ int tz_hour, tz_min;
+
+ sscanf(eot+1, "%2d%2d", &tz_hour, &tz_min);
+ /* positive time zone offset */
+ tz_offset = 3600*tz_hour + 60*tz_min;
+ }
+ else if ((eot = memchr(data.ptr, '-', data.len)) != NULL)
+ {
+ int tz_hour, tz_min;
+
+ sscanf(eot+1, "%2d%2d", &tz_hour, &tz_min);
+ /* negative time zone offset */
+ tz_offset = -3600*tz_hour - 60*tz_min;
+ }
+ else
+ {
+ /* error in time format */
+ return PARSE_ERROR;
+ }
+
+ if (this->rule->type == ASN1_UTCTIME)
+ {
+ format = "%2d%2d%2d%2d%2d";
+ }
+ else
+ {
+ format = "%4d%2d%2d%2d%2d";
+ }
+
+ sscanf(data.ptr, format, &t.tm_year, &t.tm_mon, &t.tm_mday, &t.tm_hour, &t.tm_min);
+
+ /* is there a seconds field? */
+ if ((eot - data.ptr) == ((this->rule->type == ASN1_UTCTIME)?12:14))
+ {
+ sscanf(eot-2, "%2d", &t.tm_sec);
+ }
+ else
+ {
+ t.tm_sec = 0;
+ }
+
+ /* representation of year */
+ if (t.tm_year >= 1900)
+ {
+ t.tm_year -= 1900;
+ }
+ else if (t.tm_year >= 100)
+ {
+ return PARSE_ERROR;
+ }
+ else if (t.tm_year < 50)
+ {
+ t.tm_year += 100;
+ }
+
+ /* representation of month 0..11*/
+ t.tm_mon--;
+
+ /* set daylight saving time to off */
+ t.tm_isdst = 0;
+
+ /* compensate timezone */
+
+ *result = mktime(&t) - timezone - tz_offset;
+ return SUCCESS;
+}
+
+/**
+ * Read an integer as u_int or as mpz_t
+ */
status_t read_int(private_der_decoder_t *this, chunk_t data)
{
this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_INTEGER", data);
- u_int *integ = (u_int*)((u_int8_t*)this->output + this->rule->data_offset);
- *integ = 0;
- while (data.len-- > 0)
+ if (this->rule->flags & ASN1_MPZ)
{
- *integ = 256 * (*integ) + *data.ptr++;
+ mpz_t *mpz = (mpz_t*)((u_int8_t*)this->output + this->rule->data_offset);
+ mpz_import(*mpz, data.len, 1, 1, 1, 0, data.ptr);
+ }
+ else
+ {
+ u_int *integ = (u_int*)((u_int8_t*)this->output + this->rule->data_offset);
+
+ *integ = 0;
+ while (data.len-- > 0)
+ {
+ *integ = 256 * (*integ) + *data.ptr++;
+ }
}
return SUCCESS;
}
-status_t read_mpz(private_der_decoder_t *this, chunk_t data)
+/**
+ * Read boolean value
+ */
+status_t read_bool(private_der_decoder_t *this, chunk_t data)
{
- this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_INTEGER as mpz", data);
- mpz_t *mpz = (mpz_t*)((u_int8_t*)this->output + this->rule->data_offset);
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_BOOLEAN", data);
+
+ bool *boolean = (u_int*)((u_int8_t*)this->output + this->rule->data_offset);
- mpz_import(*mpz, data.len, 1, 1, 1, 0, data.ptr);
+ *boolean = *data.ptr;
+
+ return SUCCESS;
+}
+
+/**
+ * Read an OID
+ */
+status_t read_oid(private_der_decoder_t *this, chunk_t data)
+{
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_OID", data);
+ /* TODO: OID parsing stuff */
return SUCCESS;
}
+/**
+ * Read a bitstring
+ */
+status_t read_bitstring(private_der_decoder_t *this, chunk_t data)
+{
+ /* TODO: cleanly determine amount of unused bits */
+
+ /* skip "unused-bits-in-following-byte"-byte */
+ data.ptr += 1;
+ data.len -= 1;
+
+ chunk_t *chunk = (chunk_t*)((u_int8_t*)this->output + this->rule->data_offset);
+
+ *chunk = allocator_clone_chunk(data);
+
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_BITSTRING", data);
+ return SUCCESS;
+}
+
+/**
+ * Read any type which appears in a chunk
+ */
+status_t read_any(private_der_decoder_t *this, chunk_t data)
+{
+ chunk_t *chunk = (chunk_t*)((u_int8_t*)this->output + this->rule->data_offset);
+
+ *chunk = allocator_clone_chunk(data);
+
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "ASN1_ANY", data);
+ return SUCCESS;
+}
+
+/**
+ * Read the length field of a type
+ */
u_int32_t read_length(chunk_t *data)
{
u_int8_t n;
size_t len;
/* read first octet of length field */
- n = *data->ptr++;
+ n = *data->ptr;
+ data->ptr++; data->len--;
if ((n & 0x80) == 0)
{
@@ -114,81 +330,138 @@ u_int32_t read_length(chunk_t *data)
len = 0;
while (n-- > 0)
{
- len = 256 * len + *data->ptr++;
+ len = 256 * len + *data->ptr;
+ data->ptr++; data->len--;
}
return len;
}
+/**
+ * Read the next field
+ */
status_t read_hdr(private_der_decoder_t *this, chunk_t *data)
{
chunk_t inner;
+ /* TODO: Redo this that an average mid-european can understand it */
+beginning:
/* advance to the next rule */
this->rule++;
- if (this->rule->type == ASN1_END)
- {
- return SUCCESS;
- }
-
- this->logger->log(this->logger, CONTROL|LEVEL2, "reading header of rule %s",
- mapping_find(asn1_type_m, this->rule->type));
-
- this->logger->log_chunk(this->logger, CONTROL|LEVEL2, "reading from:", *data);
-
- /* read type, advance in data */
- if (*(data->ptr) != this->rule->type)
- {
- this->logger->log(this->logger, CONTROL|LEVEL2, "Bad byte found (%x)", *data->ptr);
- return PARSE_ERROR;
- }
- data->ptr++;
- data->len--;
-
- /* read length, advance in data */
- inner.len = read_length(data);
- if (inner.len == -1)
- {
- this->logger->log(this->logger, CONTROL|LEVEL2, "Error reading length");
- return PARSE_ERROR;
- }
- this->logger->log(this->logger, CONTROL|LEVEL2, "Length is %d",
- inner.len);
- inner.ptr = data->ptr;
-
- /* advance in data */
- data->ptr += inner.len;
- data->len -= inner.len;
+ this->logger->log(this->logger, CONTROL|LEVEL2, "reading rule %d %s",
+ this->rule - this->first_rule,
+ mapping_find(asn1_type_m, this->rule->type));
- /* process inner */
switch (this->rule->type)
{
- case ASN1_INTEGER:
- if (this->rule->flags & ASN1_MPZ)
+ case ASN1_END:
+ /* ignore, handled outside */
+ return SUCCESS;
+ case ASN1_CHOICE:
+ /* CHOICE has no type/length */
+ break;
+ default:
+ /* anything else has type/length */
+ if (data->len == 0)
{
- read_mpz(this, inner);
+ goto beginning;
}
- else
+ this->logger->log_chunk(this->logger, CONTROL|LEVEL3, "reading from:", *data);
+
+ /* read type, advance in data */
+ if (this->rule->type != ASN1_ANY && *(data->ptr) != this->rule->type)
{
- read_int(this, inner);
+ if (this->rule->flags & ASN1_OPTIONAL)
+ {
+ goto beginning;
+ }
+ if (this->rule->flags & ASN1_DEFAULT)
+ {
+ goto beginning;
+ }
+ this->logger->log(this->logger, CONTROL|LEVEL2, "Bad byte found: %x, %x expected",
+ *data->ptr, this->rule->type);
+ return PARSE_ERROR;
}
- break;
- case ASN1_SEQUENCE:
- read_sequence(this, inner);
- break;
- default:
- break;
+ data->ptr++;
+ data->len--;
+
+ /* read length, advance in data */
+ inner.len = read_length(data);
+ if (inner.len == -1)
+ {
+ this->logger->log(this->logger, CONTROL|LEVEL2, "Error reading length");
+ return PARSE_ERROR;
+ }
+ this->logger->log(this->logger, CONTROL|LEVEL2, "Length is %d", inner.len);
+ inner.ptr = data->ptr;
+
+ /* advance in data, at the size of the inner */
+ data->ptr += inner.len;
+ data->len -= inner.len;
}
- return SUCCESS;
+ /* process inner */
+ while (TRUE)
+ {
+ switch (this->rule->type)
+ {
+ case ASN1_INTEGER:
+ return read_int(this, inner);
+ case ASN1_BOOLEAN:
+ return read_bool(this, inner);
+ case ASN1_SEQUENCE:
+ case ASN1_SET:
+ return read_sequence(this, inner);
+ case ASN1_TAG_E_0:
+ case ASN1_TAG_E_1:
+ case ASN1_TAG_E_2:
+ case ASN1_TAG_E_3:
+ case ASN1_TAG_E_4:
+ case ASN1_TAG_E_5:
+ case ASN1_TAG_E_6:
+ case ASN1_TAG_E_7:
+ return read_hdr(this, &inner);
+ case ASN1_TAG_I_0:
+ case ASN1_TAG_I_1:
+ case ASN1_TAG_I_2:
+ case ASN1_TAG_I_3:
+ case ASN1_TAG_I_4:
+ case ASN1_TAG_I_5:
+ case ASN1_TAG_I_6:
+ case ASN1_TAG_I_7:
+ this->rule++;
+ continue;
+ case ASN1_OID:
+ return read_oid(this, inner);
+ case ASN1_CHOICE:
+ return read_choice(this, data);
+ case ASN1_NULL:
+ return SUCCESS;
+ case ASN1_ANY:
+ return read_any(this, inner);
+ case ASN1_UTCTIME:
+ return read_time(this, inner);
+ case ASN1_GENERALIZEDTIME:
+ return read_time(this, inner);
+ case ASN1_BITSTRING:
+ return read_bitstring(this, inner);
+ case ASN1_OCTETSTRING:
+ return read_any(this, inner);
+ default:
+ return NOT_SUPPORTED;
+ }
+ }
}
-
-
+/**
+ * Implements der_decoder_t.decode
+ */
status_t decode(private_der_decoder_t *this, chunk_t input, void *output)
{
this->rule = this->first_rule - 1;
this->output = output;
+ /* start parsing recursivly */
return read_hdr(this, &input);
}
diff --git a/Source/charon/asn1/der_decoder.h b/Source/charon/asn1/der_decoder.h
index d6ccaf4cc..68731b5d9 100644
--- a/Source/charon/asn1/der_decoder.h
+++ b/Source/charon/asn1/der_decoder.h
@@ -29,15 +29,29 @@
typedef struct der_decoder_t der_decoder_t;
/**
- * @brief Decode der_encoded bytes to usable structures.
+ * @brief Decode ASN1 DER encoded chunks.
*
* @b Constructors:
* - der_decoder_create()
*
+ * @todo A lot.
+ *
* @ingroup asn1
*/
struct der_decoder_t {
+ /**
+ * @brief Decode a chunk of bytes to a data structure
+ *
+ * @param der_decoder calling object
+ * @param input chunk of data to decode
+ * @param output data structure where decoded data is written
+ * @return
+ * - PARSE_ERROR
+ * - FAILED
+ * - NOT_SUPPORTED
+ * - or SUCCESS sometimes
+ */
status_t (*decode) (der_decoder_t *this, chunk_t input, void *output);
/**
@@ -52,7 +66,11 @@ struct der_decoder_t {
/**
* @brief Create a der_decoder instance.
*
- * @return der_decoder_t object
+ * The instance needs ASN1 rules to know how to decode
+ * data...
+ *
+ * @param rules set of ASN1 coding rules
+ * @return der_decoder_t object
*
* @ingroup ans1
*/
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-20 02:18:28 +0000