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authorLukas Larsson <[email protected]>2011-07-01 15:51:31 +0200
committerLukas Larsson <[email protected]>2011-08-01 16:37:59 +0200
commitf4b38eec4b0eccab59cdfb0610124bd20c0d7802 (patch)
treef82913e84b57b6f5a05a09ece8defa8f7d18ce1e /lib/asn1/c_src/asn1_erl_nif.c
parenta9b234504e155f1c44d7d1f93532c3224e10f439 (diff)
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Add asn1 nif for ber decode and per encode
Diffstat (limited to 'lib/asn1/c_src/asn1_erl_nif.c')
-rw-r--r--lib/asn1/c_src/asn1_erl_nif.c1047
1 files changed, 1047 insertions, 0 deletions
diff --git a/lib/asn1/c_src/asn1_erl_nif.c b/lib/asn1/c_src/asn1_erl_nif.c
new file mode 100644
index 0000000000..cf3041c45c
--- /dev/null
+++ b/lib/asn1/c_src/asn1_erl_nif.c
@@ -0,0 +1,1047 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2002-2011. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ *
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "erl_nif.h"
+
+/* #define ASN1_DEBUG 1 */
+
+#define ASN1_OK 0
+#define ASN1_ERROR -1
+#define ASN1_COMPL_ERROR 1
+#define ASN1_MEMORY_ERROR 0
+#define ASN1_DECODE_ERROR 2
+#define ASN1_TAG_ERROR -3
+#define ASN1_LEN_ERROR -4
+#define ASN1_INDEF_LEN_ERROR -5
+#define ASN1_VALUE_ERROR -6
+
+#define ASN1_CLASS 0xc0
+#define ASN1_FORM 0x20
+#define ASN1_CLASSFORM (ASN1_CLASS | ASN1_FORM)
+#define ASN1_TAG 0x1f
+#define ASN1_LONG_TAG 0x7f
+
+#define ASN1_INDEFINITE_LENGTH 0x80
+#define ASN1_SHORT_DEFINITE_LENGTH 0
+
+#define ASN1_PRIMITIVE 0
+#define ASN1_CONSTRUCTED 0x20
+
+#define ASN1_COMPLETE 1
+#define ASN1_BER_TLV_DECODE 2
+#define ASN1_BER_TLV_PARTIAL_DECODE 3
+
+#define ASN1_NOVALUE 0
+
+#define ASN1_SKIPPED 0
+#define ASN1_OPTIONAL 1
+#define ASN1_CHOOSEN 2
+
+#define CEIL(X,Y) ((X-1) / Y + 1)
+
+#define INVMASK(X,M) (X & (M ^ 0xff))
+#define MASK(X,M) (X & M)
+
+int complete(ErlNifBinary *, unsigned char *, int );
+
+int insert_octets(int, unsigned char **, unsigned char **, int *);
+
+int insert_octets_except_unused(int, unsigned char **, unsigned char **, int *,
+ int);
+
+int insert_octets_as_bits_exact_len(int, int, unsigned char **,
+ unsigned char **, int *);
+
+int insert_octets_as_bits(int, unsigned char **, unsigned char **, int *);
+
+int pad_bits(int, unsigned char **, int *);
+
+int insert_least_sign_bits(int, unsigned char, unsigned char **, int *);
+
+int insert_most_sign_bits(int, unsigned char, unsigned char **, int *);
+
+int insert_bits_as_bits(int, int, unsigned char **, unsigned char **, int *);
+
+int insert_octets_unaligned(int, unsigned char **, unsigned char **, int);
+
+int realloc_memory(ErlNifBinary *, int, unsigned char **);
+
+int decode_begin(ErlNifEnv *, ERL_NIF_TERM *, unsigned char *, int,
+ unsigned int *);
+
+int decode(ErlNifEnv *, ERL_NIF_TERM *, unsigned char *, int *, int);
+
+int decode_tag(ErlNifEnv *, ERL_NIF_TERM *, unsigned char *, int, int *);
+
+int decode_value(ErlNifEnv*, ERL_NIF_TERM *, unsigned char *, int *, int, int);
+
+/*
+ *
+ * This section defines functionality for the complete encode of a
+ * PER encoded message
+ *
+ */
+
+int complete(ErlNifBinary *out_binary, unsigned char *in_buf, int in_buf_len) {
+ int counter = in_buf_len;
+ /* counter keeps track of number of bytes left in the
+ input buffer */
+
+ int buf_space = in_buf_len;
+ /* This is the amount of allocated space left of the out_binary. It
+ is possible when padding is applied that more space is needed than
+ was originally allocated. */
+
+ int buf_size = in_buf_len;
+ /* Size of the buffer. May become reallocated and thus other than
+ in_buf_len */
+
+ unsigned char *in_ptr, *ptr;
+ /* in_ptr points at the next byte in in_buf to be moved to
+ complete_buf.
+ ptr points into the new completed buffer, complete_buf, at the
+ position of the next byte that will be set */
+ int unused = 8;
+ /* unused = [1,...,8] indicates how many of the rigthmost bits of
+ the byte that ptr points at that are unassigned */
+
+ int no_bits, no_bytes, in_unused, desired_len, ret, saved_mem, needed,
+ pad_bits;
+
+ unsigned char val;
+
+ in_ptr = in_buf;
+ ptr = out_binary->data;
+ *ptr = 0x00;
+ while (counter > 0) {
+ counter--;
+ switch (*in_ptr) {
+ case 0:
+ /* just one zero-bit should be added to the buffer */
+ if (unused == 1) {
+ unused = 8;
+ *++ptr = 0x00;
+ buf_space--;
+ } else
+ unused--;
+ break;
+
+ case 1:
+ /* one one-bit should be added to the buffer */
+ if (unused == 1) {
+ *ptr = *ptr | 1;
+ unused = 8;
+ *++ptr = 0x00;
+ buf_space--;
+ } else {
+ *ptr = *ptr | (1 << (unused - 1));
+ unused--;
+ }
+ break;
+
+ case 2:
+ /* align buffer to end of byte */
+ if (unused != 8) {
+ *++ptr = 0x00;
+ buf_space--;
+ unused = 8;
+ }
+ break;
+
+ case 10:
+ /* next byte in in_buf tells how many bits in the second next
+ byte that will be used */
+ /* The leftmost unused bits in the value byte are supposed to be
+ zero bits */
+ no_bits = (int) *(++in_ptr);
+ val = *(++in_ptr);
+ counter -= 2;
+ if ((ret = insert_least_sign_bits(no_bits, val, &ptr, &unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 20:
+ /* in this case the next value in_ptr points at holds the number
+ of following bytes that holds the value that will be inserted
+ in the completed buffer */
+ no_bytes = (int) *(++in_ptr);
+ counter -= (no_bytes + 1);
+ if ((counter < 0)
+ || (ret = insert_octets(no_bytes, &in_ptr, &ptr, &unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 21:
+ /* in this case the next two bytes in_ptr points at holds the number
+ of following bytes that holds the value that will be inserted
+ in the completed buffer */
+ no_bytes = (int) *(++in_ptr);
+ no_bytes = no_bytes << 8;
+ no_bytes = no_bytes | (int) *(++in_ptr);
+ counter -= (2 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets(no_bytes, &in_ptr, &ptr, &unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 30:
+ /* If we call the following bytes, in the buffer in_ptr points at,
+ By1,By2,Rest then Rest is the value that will be transfered to
+ the completed buffer. By1 tells how many of the rightmost bits in
+ Rest that should not be used. By2 is the length of Rest in bytes.*/
+ in_unused = (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+ counter -= (2 + no_bytes);
+ ret = -4711;
+ if ((counter < 0)
+ || (ret = insert_octets_except_unused(no_bytes, &in_ptr,
+ &ptr, &unused, in_unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 31:
+ /* If we call the following bytes, in the buffer in_ptr points at,
+ By1,By2,By3,Rest then Rest is the value that will be transfered to
+ the completed buffer. By1 tells how many of the rightmost bits in
+ Rest that should not be used. By2 and By3 is the length of
+ Rest in bytes.*/
+ in_unused = (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+ no_bytes = no_bytes << 8;
+ no_bytes = no_bytes | (int) *(++in_ptr);
+ counter -= (3 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets_except_unused(no_bytes, &in_ptr,
+ &ptr, &unused, in_unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 40:
+ /* This case implies that next byte,By1,(..,By1,By2,Bin,...)
+ is the desired length of the completed value, maybe needs
+ padding zero bits or removal of trailing zero bits from Bin.
+ By2 is the length of Bin and Bin is the value that will be
+ put into the completed buffer. Each byte in Bin has the value
+ 1 or 0.*/
+ desired_len = (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+
+ /* This is the algorithm for need of memory reallocation:
+ Only when padding (cases 40 - 43,45 - 47) more memory may be
+ used than allocated. Therefore one has to keep track of how
+ much of the allocated memory that has been saved, i.e. the
+ difference between the number of parsed bytes of the input buffer
+ and the number of used bytes of the output buffer.
+ If saved memory is less than needed for the padding then we
+ need more memory. */
+ saved_mem = buf_space - counter;
+ pad_bits = desired_len - no_bytes - unused;
+ needed = (pad_bits > 0) ? CEIL(pad_bits,8) : 0;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (2 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets_as_bits_exact_len(desired_len,
+ no_bytes, &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 41:
+ /* Same as case 40 apart from By2, the length of Bin, which is in
+ two bytes*/
+ desired_len = (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+ no_bytes = no_bytes << 8;
+ no_bytes = no_bytes | (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (3 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets_as_bits_exact_len(desired_len,
+ no_bytes, &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 42:
+ /* Same as case 40 apart from By1, the desired length, which is in
+ two bytes*/
+ desired_len = (int) *(++in_ptr);
+ desired_len = desired_len << 8;
+ desired_len = desired_len | (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (3 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets_as_bits_exact_len(desired_len,
+ no_bytes, &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 43:
+ /* Same as case 40 apart from By1 and By2, the desired length and
+ the length of Bin, which are in two bytes each. */
+ desired_len = (int) *(++in_ptr);
+ desired_len = desired_len << 8;
+ desired_len = desired_len | (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+ no_bytes = no_bytes << 8;
+ no_bytes = no_bytes | (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (4 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_octets_as_bits_exact_len(desired_len,
+ no_bytes, &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 45:
+ /* This case assumes that the following bytes in the incoming buffer
+ (called By1,By2,Bin) is By1, which is the number of bits (n) that
+ will be inserted in the completed buffer. By2 is the number of
+ bytes in Bin. Each bit in the buffer Bin should be inserted from
+ the leftmost until the nth.*/
+ desired_len = (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (2 + no_bytes);
+
+ if ((counter < 0)
+ || (ret = insert_bits_as_bits(desired_len, no_bytes,
+ &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 46:
+ /* Same as case 45 apart from By1, the desired length, which is
+ in two bytes. */
+ desired_len = (int) *(++in_ptr);
+ desired_len = desired_len << 8;
+ desired_len = desired_len | (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (3 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_bits_as_bits(desired_len, no_bytes,
+ &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ case 47:
+ /* Same as case 45 apart from By1 and By2, the desired length
+ and the length of Bin, which are in two bytes each. */
+ desired_len = (int) *(++in_ptr);
+ desired_len = desired_len << 8;
+ desired_len = desired_len | (int) *(++in_ptr);
+ no_bytes = (int) *(++in_ptr);
+ no_bytes = no_bytes << 8;
+ no_bytes = no_bytes | (int) *(++in_ptr);
+
+ saved_mem = buf_space - counter;
+ needed = CEIL((desired_len-unused),8) - no_bytes;
+ if (saved_mem < needed) {
+ /* Have to allocate more memory */
+ buf_size += needed;
+ buf_space += needed;
+ if (realloc_memory(out_binary, buf_size, &ptr)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ }
+
+ counter -= (4 + no_bytes);
+ if ((counter < 0)
+ || (ret = insert_bits_as_bits(desired_len, no_bytes,
+ &in_ptr, &ptr, &unused)) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ buf_space -= ret;
+ break;
+
+ default:
+ return ASN1_ERROR;
+ }
+ in_ptr++;
+ }
+ /* The returned buffer must be at least one byte and
+ it must be octet aligned */
+ if ((unused == 8) && (ptr != out_binary->data))
+ return (ptr - out_binary->data);
+ else {
+ ptr++; /* octet align buffer */
+ return (ptr - out_binary->data);
+ }
+}
+
+int realloc_memory(ErlNifBinary *binary, int amount, unsigned char **ptr) {
+
+ int i = *ptr - binary->data;
+
+ if (!enif_realloc_binary(binary, amount)) {
+ /*error handling due to memory allocation failure */
+ return ASN1_ERROR;
+ } else {
+ *ptr = binary->data + i;
+ }
+ return ASN1_OK;
+}
+
+int insert_most_sign_bits(int no_bits, unsigned char val,
+ unsigned char **output_ptr, int *unused) {
+ unsigned char *ptr = *output_ptr;
+
+ if (no_bits < *unused) {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *unused -= no_bits;
+ } else if (no_bits == *unused) {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *unused = 8;
+ *++ptr = 0x00;
+ } else {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *++ptr = 0x00;
+ *ptr = *ptr | (val << *unused);
+ *unused = 8 - (no_bits - *unused);
+ }
+ *output_ptr = ptr;
+ return ASN1_OK;
+}
+
+int insert_least_sign_bits(int no_bits, unsigned char val,
+ unsigned char **output_ptr, int *unused) {
+ unsigned char *ptr = *output_ptr;
+ int ret = 0;
+
+ if (no_bits < *unused) {
+ *ptr = *ptr | (val << (*unused - no_bits));
+ *unused -= no_bits;
+ } else if (no_bits == *unused) {
+ *ptr = *ptr | val;
+ *unused = 8;
+ *++ptr = 0x00;
+ ret++;
+ } else {
+ /* first in the begun byte in the completed buffer insert
+ so many bits that fit, then insert the rest in next byte.*/
+ *ptr = *ptr | (val >> (no_bits - *unused));
+ *++ptr = 0x00;
+ ret++;
+ *ptr = *ptr | (val << (8 - (no_bits - *unused)));
+ *unused = 8 - (no_bits - *unused);
+ }
+ *output_ptr = ptr;
+ return ret;
+}
+
+/* pad_bits adds no_bits bits in the buffer that output_ptr
+ points at.
+ */
+int pad_bits(int no_bits, unsigned char **output_ptr, int *unused) {
+ unsigned char *ptr = *output_ptr;
+ int ret = 0;
+
+ while (no_bits > 0) {
+ if (*unused == 1) {
+ *unused = 8;
+ *++ptr = 0x00;
+ ret++;
+ } else
+ (*unused)--;
+ no_bits--;
+ }
+ *output_ptr = ptr;
+ return ret;
+}
+
+/* insert_bits_as_bits removes no_bytes bytes from the buffer that in_ptr
+ points at and takes the desired_no leftmost bits from those removed
+ bytes and inserts them in the buffer(output buffer) that ptr points at.
+ The unused parameter tells how many bits that are not set in the
+ actual byte in the output buffer. If desired_no is more bits than the
+ input buffer has in no_bytes bytes, then zero bits is padded.*/
+int insert_bits_as_bits(int desired_no, int no_bytes, unsigned char **input_ptr,
+ unsigned char **output_ptr, int *unused) {
+ unsigned char *in_ptr = *input_ptr;
+ unsigned char val;
+ int no_bits, ret, ret2;
+
+ if (desired_no == (no_bytes * 8)) {
+ if (insert_octets_unaligned(no_bytes, &in_ptr, output_ptr, *unused)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ ret = no_bytes;
+ } else if (desired_no < (no_bytes * 8)) {
+ /* printf("insert_bits_as_bits 1\n\r"); */
+ if (insert_octets_unaligned(desired_no / 8, &in_ptr, output_ptr,
+ *unused) == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ /* printf("insert_bits_as_bits 2\n\r"); */
+ val = *++in_ptr;
+ /* printf("val = %d\n\r",(int)val); */
+ no_bits = desired_no % 8;
+ /* printf("no_bits = %d\n\r",no_bits); */
+ insert_most_sign_bits(no_bits, val, output_ptr, unused);
+ ret = CEIL(desired_no,8);
+ } else {
+ if (insert_octets_unaligned(no_bytes, &in_ptr, output_ptr, *unused)
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ ret2 = pad_bits(desired_no - (no_bytes * 8), output_ptr, unused);
+ /* printf("ret2 = %d\n\r",ret2); */
+ ret = CEIL(desired_no,8);
+ /* printf("ret = %d\n\r",ret); */
+ }
+ /* printf("*unused = %d\n\r",*unused); */
+ *input_ptr = in_ptr;
+ return ret;
+}
+
+/* insert_octets_as_bits_exact_len */
+int insert_octets_as_bits_exact_len(int desired_len, int in_buff_len,
+ unsigned char **in_ptr, unsigned char **ptr, int *unused) {
+ int ret = 0;
+ int ret2 = 0;
+
+ if (desired_len == in_buff_len) {
+ if ((ret = insert_octets_as_bits(in_buff_len, in_ptr, ptr, unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ } else if (desired_len > in_buff_len) {
+ if ((ret = insert_octets_as_bits(in_buff_len, in_ptr, ptr, unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ /* now pad with zero bits */
+ /* printf("~npad_bits: called with %d bits padding~n~n~r",desired_len - in_buff_len); */
+ if ((ret2 = pad_bits(desired_len - in_buff_len, ptr, unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ } else {/* desired_len < no_bits */
+ if ((ret = insert_octets_as_bits(desired_len, in_ptr, ptr, unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ /* now remove no_bits - desired_len bytes from in buffer */
+ *in_ptr += (in_buff_len - desired_len);
+ }
+ return (ret + ret2);
+}
+
+/* insert_octets_as_bits takes no_bytes bytes from the buffer that input_ptr
+ points at and inserts the least significant bit of it in the buffer that
+ output_ptr points at. Each byte in the input buffer must be 1 or 0
+ otherwise the function returns ASN1_ERROR. The output buffer is concatenated
+ without alignment.
+ */
+int insert_octets_as_bits(int no_bytes, unsigned char **input_ptr,
+ unsigned char **output_ptr, int *unused) {
+ unsigned char *in_ptr = *input_ptr;
+ unsigned char *ptr = *output_ptr;
+ int used_bits = 8 - *unused;
+
+ while (no_bytes > 0) {
+ switch (*++in_ptr) {
+ case 0:
+ if (*unused == 1) {
+ *unused = 8;
+ *++ptr = 0x00;
+ } else
+ (*unused)--;
+ break;
+ case 1:
+ if (*unused == 1) {
+ *ptr = *ptr | 1;
+ *unused = 8;
+ *++ptr = 0x00;
+ } else {
+ *ptr = *ptr | (1 << (*unused - 1));
+ (*unused)--;
+ }
+ break;
+ default:
+ return ASN1_ERROR;
+ }
+ no_bytes--;
+ }
+ *input_ptr = in_ptr;
+ *output_ptr = ptr;
+ return ((used_bits + no_bytes) / 8); /*return number of new bytes
+ in completed buffer */
+}
+
+/* insert_octets inserts bytes from the input buffer, *input_ptr,
+ into the output buffer, *output_ptr. Before the first byte is
+ inserted the input buffer is aligned.
+ */
+int insert_octets(int no_bytes, unsigned char **input_ptr,
+ unsigned char **output_ptr, int *unused) {
+ unsigned char *in_ptr = *input_ptr;
+ unsigned char *ptr = *output_ptr;
+ int ret = 0;
+
+ if (*unused != 8) {/* must align before octets are added */
+ *++ptr = 0x00;
+ ret++;
+ *unused = 8;
+ }
+ while (no_bytes > 0) {
+ *ptr = *(++in_ptr);
+ *++ptr = 0x00;
+ /* *unused = *unused - 1; */
+ no_bytes--;
+ }
+ *input_ptr = in_ptr;
+ *output_ptr = ptr;
+ return (ret + no_bytes);
+}
+
+/* insert_octets_unaligned inserts bytes from the input buffer, *input_ptr,
+ into the output buffer, *output_ptr.No alignment is done.
+ */
+int insert_octets_unaligned(int no_bytes, unsigned char **input_ptr,
+ unsigned char **output_ptr, int unused) {
+ unsigned char *in_ptr = *input_ptr;
+ unsigned char *ptr = *output_ptr;
+ int n = no_bytes;
+ unsigned char val;
+
+ while (n > 0) {
+ if (unused == 8) {
+ *ptr = *++in_ptr;
+ *++ptr = 0x00;
+ } else {
+ val = *++in_ptr;
+ *ptr = *ptr | val >> (8 - unused);
+ *++ptr = 0x00;
+ *ptr = val << unused;
+ }
+ n--;
+ }
+ *input_ptr = in_ptr;
+ *output_ptr = ptr;
+ return no_bytes;
+}
+
+int insert_octets_except_unused(int no_bytes, unsigned char **input_ptr,
+ unsigned char **output_ptr, int *unused, int in_unused) {
+ unsigned char *in_ptr = *input_ptr;
+ unsigned char *ptr = *output_ptr;
+ int val, no_bits;
+ int ret = 0;
+
+ if (in_unused == 0) {
+ if ((ret = insert_octets_unaligned(no_bytes, &in_ptr, &ptr, *unused))
+ == ASN1_ERROR
+ )
+ return ASN1_ERROR;
+ } else {
+ if ((ret = insert_octets_unaligned(no_bytes - 1, &in_ptr, &ptr, *unused))
+ != ASN1_ERROR) {
+ val = (int) *(++in_ptr);
+ no_bits = 8 - in_unused;
+ /* no_bits is always less than *unused since the buffer is
+ octet aligned after insert:octets call, so the following
+ if clasuse is obsolete I think */
+ if (no_bits < *unused) {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *unused = *unused - no_bits;
+ } else if (no_bits == *unused) {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *++ptr = 0x00;
+ ret++;
+ *unused = 8;
+ } else {
+ *ptr = *ptr | (val >> (8 - *unused));
+ *++ptr = 0x00;
+ ret++;
+ *ptr = *ptr | (val << *unused);
+ *unused = 8 - (no_bits - *unused);
+ }
+ } else
+ return ASN1_ERROR;
+ }
+ *input_ptr = in_ptr;
+ *output_ptr = ptr;
+ return ret;
+}
+
+/*
+ *
+ * This section defines functionality for the partial decode of a
+ * BER encoded message
+ *
+ */
+
+/*
+ * int decode(ErlNifEnv* env, ERL_NIF_TERM *term, unsigned char *in_buf,
+ int in_buf_len, unsigned int *err_pos)
+ * term is a pointer to the term which is to be returned to erlang
+ * in_buf is a pointer into the buffer of incoming bytes.
+ * in_buf_len is the length of the incoming buffer.
+ * The function reads the bytes in the incoming buffer and structures
+ * it in a nested way as Erlang terms. The buffer contains data in the
+ * order tag - length - value. Tag, length and value has the following
+ * format:
+ * A tag is normally one byte but may be of any length, if the tag number
+ * is greater than 30. +----------+
+ * |CL|C|NNNNN|
+ * +----------+
+ * If NNNNN is 31 then will the 7 l.s.b of each of the following tag number
+ * bytes contain the tag number. Each tag number byte that is not the last one
+ * has the m.s.b. set to 1.
+ * The length can be short definite length (sdl), long definite length (ldl)
+ * or indefinite length (il).
+ * sdl: +---------+ the L bits is the length
+ * |0|LLLLLLL|
+ * +---------+
+ * ldl: +---------+ +---------+ +---------+ +-----------+
+ * |1|lllllll| |first len| | | |the Nth len|
+ * +---------+ +---------+ +---------+ ... +-----------+
+ * The first byte tells how many len octets will follow, max 127
+ * il: +---------+ +----------------------+ +--------+ +--------+
+ * |1|0000000| |content octets (Value)| |00000000| |00000000|
+ * +---------+ +----------------------+ +--------+ +--------+
+ * The value octets are preceded by one octet and followed by two
+ * exactly as above. The value must be some tag-length-value encoding.
+ *
+ * The function returns a value in Erlang nif term format:
+ * {{TagNo,Value},Rest}
+ * TagNo is an integer ((CL bsl 16) + tag number) which limits the tag number
+ * to 65535.
+ * Value is a binary if the C bit in tag was unset, otherwise (if tag was
+ * constructed) Value is a list, List.
+ * List is like: [{TagNo,Value},{TagNo,Value},...]
+ * Rest is a binary, i.e. the undecoded part of the buffer. Most often Rest
+ * is the empty binary.
+ * If some error occured during the decoding of the in_buf an error is returned.
+ */
+int decode_begin(ErlNifEnv* env, ERL_NIF_TERM *term, unsigned char *in_buf,
+ int in_buf_len, unsigned int *err_pos) {
+ int maybe_ret;
+ int ib_index = 0;
+ unsigned char *rest_data;
+ ERL_NIF_TERM decoded_term, rest;
+
+ if ((maybe_ret = decode(env, &decoded_term, in_buf, &ib_index, in_buf_len))
+ <= ASN1_ERROR)
+ {
+ *err_pos = ib_index;
+ return maybe_ret;
+ };
+
+ // The remaining binary after one ASN1 segment has been decoded
+ if ((rest_data = enif_make_new_binary(env, in_buf_len - ib_index, &rest))
+ == NULL) {
+ *term = enif_make_atom(env, "could_not_alloc_binary");
+ return ASN1_ERROR;
+ }
+
+ *term = enif_make_tuple2(env, decoded_term, rest);
+ return ASN1_OK;
+}
+
+int decode(ErlNifEnv* env, ERL_NIF_TERM *term, unsigned char *in_buf,
+ int *ib_index, int in_buf_len) {
+ int maybe_ret;
+ int form;
+ ERL_NIF_TERM tag, value;
+
+ /*buffer must hold at least two bytes*/
+ if ((*ib_index + 2) > in_buf_len)
+ return ASN1_VALUE_ERROR;
+ /* "{{TagNo," */
+ if ((form = decode_tag(env, &tag, in_buf, in_buf_len, ib_index))
+ <= ASN1_ERROR
+ )
+ return form; /* 5 bytes */
+ if (*ib_index >= in_buf_len) {
+ return ASN1_TAG_ERROR;
+ }
+ /* buffer must hold at least one byte (0 as length and nothing as
+ value) */
+ /* "{{TagNo,Value}," */
+ if ((maybe_ret = decode_value(env, &value, in_buf, ib_index, form,
+ in_buf_len)) <= ASN1_ERROR
+ )
+ return maybe_ret; /* at least 5 bytes */
+ *term = enif_make_tuple2(env, tag, value);
+ return ASN1_OK;
+}
+
+/*
+ * decode_tag decodes the BER encoded tag in in_buf and creates an
+ * nif term tag
+ */
+int decode_tag(ErlNifEnv* env, ERL_NIF_TERM *tag, unsigned char *in_buf,
+ int in_buf_len, int *ib_index) {
+ int tag_no, tmp_tag, form;
+
+ /* first get the class of tag and bit shift left 16*/
+ tag_no = ((MASK(in_buf[*ib_index],ASN1_CLASS)) << 10);
+
+ form = (MASK(in_buf[*ib_index],ASN1_FORM));
+
+ /* then get the tag number */
+ if ((tmp_tag = (int) INVMASK(in_buf[*ib_index],ASN1_CLASSFORM)) < 31) {
+ *tag = enif_make_ulong(env, tag_no + tmp_tag);
+ (*ib_index)++;
+ } else {
+ int n = 0; /* n is used to check that the 64K limit is not
+ exceeded*/
+
+ /* should check that at least three bytes are left in
+ in-buffer,at least two tag byte and at least one length byte */
+ if ((*ib_index + 3) > in_buf_len)
+ return ASN1_VALUE_ERROR;
+ (*ib_index)++;
+ /* The tag is in the following bytes in in_buf as
+ 1ttttttt 1ttttttt ... 0ttttttt, where the t-bits
+ is the tag number*/
+ /* In practice is the tag size limited to 64K, i.e. 16 bits. If
+ the tag is greater then 64K return an error */
+ while (((tmp_tag = (int) in_buf[*ib_index]) >= 128) && n < 2) {
+ /* m.s.b. = 1 */
+ tag_no = tag_no + (MASK(tmp_tag,ASN1_LONG_TAG) << 7);
+ (*ib_index)++;
+ n++;
+ };
+ if ((n == 2) && in_buf[*ib_index] > 3)
+ return ASN1_TAG_ERROR; /* tag number > 64K */
+ tag_no = tag_no + in_buf[*ib_index];
+ (*ib_index)++;
+ *tag = enif_make_ulong(env, tag_no);
+ }
+ return form;
+}
+
+/*
+ * decode_value decodes the BER encoded length and value fields in the
+ * in_buf and puts the value part in the decode_buf as an Erlang
+ * nif term into value
+ */
+int decode_value(ErlNifEnv* env, ERL_NIF_TERM *value, unsigned char *in_buf,
+ int *ib_index, int form, int in_buf_len) {
+ int maybe_ret;
+ unsigned int len = 0;
+ unsigned int lenoflen = 0;
+ int indef = 0;
+ unsigned char *tmp_out_buff;
+ ERL_NIF_TERM term = 0, curr_head = 0;
+
+ if (((in_buf[*ib_index]) & 0x80) == ASN1_SHORT_DEFINITE_LENGTH) {
+ len = in_buf[*ib_index];
+ } else if (in_buf[*ib_index] == ASN1_INDEFINITE_LENGTH
+ )
+ indef = 1;
+ else /* long definite length */{
+ lenoflen = (in_buf[*ib_index] & 0x7f); /*length of length */
+ if (lenoflen > (in_buf_len - (*ib_index + 1)))
+ return ASN1_LEN_ERROR;
+ len = 0;
+ while (lenoflen--) {
+ (*ib_index)++;
+ if (!(len < (1 << (sizeof(len) - 1) * 8)))
+ return ASN1_LEN_ERROR; /* length does not fit in 32 bits */
+ len = (len << 8) + in_buf[*ib_index];
+ }
+ }
+ if (len > (in_buf_len - (*ib_index + 1)))
+ return ASN1_VALUE_ERROR;
+ (*ib_index)++;
+ if (indef == 1) { /* in this case it is desireably to check that indefinite length
+ end bytes exist in inbuffer */
+ curr_head = enif_make_list(env, 0); // Might want to change this list to a binary
+ while (!(in_buf[*ib_index] == 0 && in_buf[*ib_index + 1] == 0)) {
+ if (*ib_index >= in_buf_len)
+ return ASN1_INDEF_LEN_ERROR;
+
+ if ((maybe_ret = decode(env, &term, in_buf, ib_index, in_buf_len))
+ <= ASN1_ERROR
+ )
+ return maybe_ret;
+ curr_head = enif_make_list_cell(env, term, curr_head);
+ }
+ enif_make_reverse_list(env, curr_head, value);
+ (*ib_index) += 2; /* skip the indefinite length end bytes */
+ } else if (form == ASN1_CONSTRUCTED)
+ {
+ int end_index = *ib_index + len;
+ if (end_index > in_buf_len)
+ return ASN1_LEN_ERROR;
+ curr_head = enif_make_list(env, 0); // might want to change this list to a binary
+ while (*ib_index < end_index) {
+
+ if ((maybe_ret = decode(env, &term, in_buf, ib_index, in_buf_len))
+ <= ASN1_ERROR
+ )
+ return maybe_ret;
+ curr_head = enif_make_list_cell(env, term, curr_head);
+ }
+ enif_make_reverse_list(env, curr_head, value);
+ } else {
+ if ((*ib_index + len) > in_buf_len)
+ return ASN1_LEN_ERROR;
+ tmp_out_buff = enif_make_new_binary(env, len, value);
+ memcpy(tmp_out_buff, in_buf + *ib_index, len);
+ *ib_index = *ib_index + len;
+ }
+ return ASN1_OK;
+}
+
+static ERL_NIF_TERM encode_per_complete(ErlNifEnv* env, int argc,
+ const ERL_NIF_TERM argv[]) {
+ ErlNifBinary in_binary;
+ ErlNifBinary out_binary;
+ int complete_len;
+ if (!enif_inspect_iolist_as_binary(env, argv[0], &in_binary))
+ return enif_make_atom(env, "badarg");
+
+ if (!enif_alloc_binary(in_binary.size, &out_binary))
+ return enif_make_atom(env, "alloc_binary_failed");
+
+ if ((complete_len = complete(&out_binary, in_binary.data, in_binary.size))
+ <= ASN1_ERROR) {
+ enif_release_binary(&out_binary);
+ }
+ if (complete_len < out_binary.size)
+ enif_realloc_binary(&out_binary, complete_len);
+
+ return enif_make_binary(env, &out_binary);
+}
+
+static ERL_NIF_TERM decode_ber_tlv(ErlNifEnv* env, int argc,
+ const ERL_NIF_TERM argv[]) {
+ ErlNifBinary in_binary;
+ ERL_NIF_TERM return_term;
+ unsigned int err_pos = 0, return_code;
+
+ if (!enif_inspect_iolist_as_binary(env, argv[0], &in_binary))
+ return enif_make_atom(env, "badarg");
+
+ if ((return_code = decode_begin(env, &return_term, in_binary.data,
+ in_binary.size, &err_pos)) != ASN1_OK
+ )
+ return enif_make_tuple2(env, enif_make_atom(env,"error"), enif_make_tuple3(env,
+ enif_make_atom(env,""),enif_make_int(env, return_code),enif_make_int(env, err_pos)));
+ return return_term;
+}
+
+static ErlNifFunc nif_funcs[] = { { "encode_per_complete", 1,
+ encode_per_complete }, { "decode_ber_tlv", 1, decode_ber_tlv } };
+
+ERL_NIF_INIT(asn1rt_nif, nif_funcs, NULL, NULL, NULL, NULL)