【OpenSSL】ASN1_INTEGER 转整形

缺乏、安全感 2022-09-10 06:28 226阅读 0赞

### NAME ###

ASN1\_INTEGER\_get\_uint64, ASN1\_INTEGER\_set\_uint64, ASN1\_INTEGER\_get\_int64, ASN1\_INTEGER\_get, ASN1\_INTEGER\_set\_int64, ASN1\_INTEGER\_set, BN\_to\_ASN1\_INTEGER, ASN1\_INTEGER\_to\_BN, ASN1\_ENUMERATED\_get\_int64, ASN1\_ENUMERATED\_get, ASN1\_ENUMERATED\_set\_int64, ASN1\_ENUMERATED\_set, BN\_to\_ASN1\_ENUMERATED, ASN1\_ENUMERATED\_to\_BN - ASN.1 INTEGER and ENUMERATED utilities

### SYNOPSIS ###

>  \#include <openssl/asn1.h>
> 
>  int ASN1\_INTEGER\_get\_int64(int64\_t \*pr, const ASN1\_INTEGER \*a);  
> ** long ASN1\_INTEGER\_get(const ASN1\_INTEGER \*a);**
> 
>  int ASN1\_INTEGER\_set\_int64(ASN1\_INTEGER \*a, int64\_t r);  
>  int ASN1\_INTEGER\_set(const ASN1\_INTEGER \*a, long v);
> 
> **Tip:注意接口参数类型，函数参数如果不是uint64\_t，可能会存在越界的问题**
> 
> ** int ASN1\_INTEGER\_get\_uint64(uint64\_t \*pr,  const ASN1\_INTEGER \*a);**  
>  int **ASN1\_INTEGER\_set\_uint64**(ASN1\_INTEGER \*a,  uint64\_t r);
> 
>  ASN1\_INTEGER \*BN\_to\_ASN1\_INTEGER(const BIGNUM \*bn, ASN1\_INTEGER \*ai);  
>  BIGNUM \*ASN1\_INTEGER\_to\_BN(const ASN1\_INTEGER \*ai, BIGNUM \*bn);
> 
>  int ASN1\_ENUMERATED\_get\_int64(int64\_t \*pr, const ASN1\_ENUMERATED \*a);  
>  long ASN1\_ENUMERATED\_get(const ASN1\_ENUMERATED \*a);
> 
>  int ASN1\_ENUMERATED\_set\_int64(ASN1\_ENUMERATED \*a, int64\_t r);  
>  int ASN1\_ENUMERATED\_set(ASN1\_ENUMERATED \*a, long v);
> 
>  ASN1\_ENUMERATED \*BN\_to\_ASN1\_ENUMERATED(BIGNUM \*bn, ASN1\_ENUMERATED \*ai);  
>  BIGNUM \*ASN1\_ENUMERATED\_to\_BN(ASN1\_ENUMERATED \*ai, BIGNUM \*bn);

### DESCRIPTION ###

These functions convert to and from **ASN1\_INTEGER** and **ASN1\_ENUMERATED** structures.

ASN1\_INTEGER\_get\_int64() converts an **ASN1\_INTEGER** into an **int64\_t** type If successful it returns 1 and sets *\*pr* to the value of *a*. If it fails (due to invalid type or the value being too big to fit into an **int64\_t** type) it returns 0.

**ASN1\_INTEGER\_get\_uint64()** is similar to ASN1\_INTEGER\_get\_int64\_t() except it converts to a **uint64\_t** type and an error is returned if the passed integer is negative.

ASN1\_INTEGER\_get() also returns the value of *a* but it returns 0 if *a* is NULL and -1 on error (which is ambiguous because -1 is a legitimate value for an **ASN1\_INTEGER**). New applications should use ASN1\_INTEGER\_get\_int64() instead.

ASN1\_INTEGER\_set\_int64() sets the value of **ASN1\_INTEGER** *a* to the **int64\_t** value *r*.

**ASN1\_INTEGER\_set\_uint64()** sets the value of **ASN1\_INTEGER** *a* to the **uint64\_t** value *r*.

ASN1\_INTEGER\_set() sets the value of **ASN1\_INTEGER** *a* to the *long* value *v*.

BN\_to\_ASN1\_INTEGER() converts **BIGNUM** *bn* to an **ASN1\_INTEGER**. If *ai* is NULL a new **ASN1\_INTEGER** structure is returned. If *ai* is not NULL then the existing structure will be used instead.

ASN1\_INTEGER\_to\_BN() converts ASN1\_INTEGER *ai* into a **BIGNUM**. If *bn* is NULL a new **BIGNUM** structure is returned. If *bn* is not NULL then the existing structure will be used instead.

ASN1\_ENUMERATED\_get\_int64(), ASN1\_ENUMERATED\_set\_int64(), ASN1\_ENUMERATED\_set(), BN\_to\_ASN1\_ENUMERATED() and ASN1\_ENUMERATED\_to\_BN() behave in an identical way to their ASN1\_INTEGER counterparts except they operate on an **ASN1\_ENUMERATED** value.

ASN1\_ENUMERATED\_get() returns the value of *a* in a similar way to ASN1\_INTEGER\_get() but it returns **0xffffffffL** if the value of *a* will not fit in a long type. New applications should use ASN1\_ENUMERATED\_get\_int64() instead.

### NOTES ###

In general an **ASN1\_INTEGER** or **ASN1\_ENUMERATED** type can contain an integer of almost arbitrary size and so cannot always be represented by a C **int64\_t** type. However, in many cases (for example version numbers) they represent small integers which can be more easily manipulated if converted to an appropriate C integer type.

### BUGS ###

The ambiguous return values of ASN1\_INTEGER\_get() and ASN1\_ENUMERATED\_get() mean these functions should be avoided if possible. They are retained for compatibility. Normally the ambiguous return values are not legitimate values for the fields they represent.

### RETURN VALUES ###

ASN1\_INTEGER\_set\_int64(), ASN1\_INTEGER\_set(), ASN1\_ENUMERATED\_set\_int64() and ASN1\_ENUMERATED\_set() return 1 for success and 0 for failure. They will only fail if a memory allocation error occurs.

ASN1\_INTEGER\_get\_int64() and ASN1\_ENUMERATED\_get\_int64() return 1 for success and 0 for failure. They will fail if the passed type is incorrect (this will only happen if there is a programming error) or if the value exceeds the range of an **int64\_t** type.

BN\_to\_ASN1\_INTEGER() and BN\_to\_ASN1\_ENUMERATED() return an **ASN1\_INTEGER** or **ASN1\_ENUMERATED** structure respectively or NULL if an error occurs. They will only fail due to a memory allocation error.

ASN1\_INTEGER\_to\_BN() and ASN1\_ENUMERATED\_to\_BN() return a **BIGNUM** structure of NULL if an error occurs. They can fail if the passed type is incorrect (due to programming error) or due to a memory allocation failure.

### SEE ALSO ###

[ERR\_get\_error(3)][ERR_get_error_3]

### HISTORY ###

ASN1\_INTEGER\_set\_int64(), ASN1\_INTEGER\_get\_int64(), ASN1\_ENUMERATED\_set\_int64() and ASN1\_ENUMERATED\_get\_int64() were added in OpenSSL 1.1.0.

[ERR_get_error_3]: https://www.openssl.org/docs/manmaster/man3/ERR_get_error.html