xmldsig: XML Security Library Reference Manual

## xmldsig xmldsig — XML Digital Signature functions. |

## Stability Level

Stable, unless otherwise indicated

## Functions

xmlSecDSigCtxPtr | xmlSecDSigCtxCreate ()
void | xmlSecDSigCtxDestroy ()
int | xmlSecDSigCtxInitialize ()
void | xmlSecDSigCtxFinalize ()
int | xmlSecDSigCtxSign ()
int | xmlSecDSigCtxVerify ()
int | xmlSecDSigCtxEnableReferenceTransform ()
int | xmlSecDSigCtxEnableSignatureTransform ()
xmlSecBufferPtr | xmlSecDSigCtxGetPreSignBuffer ()
void | xmlSecDSigCtxDebugDump ()
void | xmlSecDSigCtxDebugXmlDump ()
xmlSecDSigReferenceCtxPtr | xmlSecDSigReferenceCtxCreate ()
void | xmlSecDSigReferenceCtxDestroy ()
int | xmlSecDSigReferenceCtxInitialize ()
void | xmlSecDSigReferenceCtxFinalize ()
int | xmlSecDSigReferenceCtxProcessNode ()
xmlSecBufferPtr | xmlSecDSigReferenceCtxGetPreDigestBuffer ()
void | xmlSecDSigReferenceCtxDebugDump ()
void | xmlSecDSigReferenceCtxDebugXmlDump ()
xmlSecPtrListId | xmlSecDSigReferenceCtxListGetKlass ()

## Types and Values

enum | xmlSecDSigStatus
#define | XMLSEC_DSIG_FLAGS_IGNORE_MANIFESTS
#define | XMLSEC_DSIG_FLAGS_STORE_SIGNEDINFO_REFERENCES
#define | XMLSEC_DSIG_FLAGS_STORE_MANIFEST_REFERENCES
#define | XMLSEC_DSIG_FLAGS_STORE_SIGNATURE
#define | XMLSEC_DSIG_FLAGS_USE_VISA3D_HACK
struct | xmlSecDSigCtx
enum | xmlSecDSigReferenceOrigin
struct | xmlSecDSigReferenceCtx
#define | xmlSecDSigReferenceCtxListId

## Description

XML Digital Signature implementation.

## Functions

### xmlSecDSigCtxCreate ()

    xmlSecDSigCtxPtr
    xmlSecDSigCtxCreate (xmlSecKeysMngrPtr keysMngr);

Creates <dsig:Signature/> element processing context. The caller is responsible for destroying returned object by calling xmlSecDSigCtxDestroy function.

#### Parameters

keysMngr | the pointer to keys manager. |

#### Returns

pointer to newly allocated context object or NULL if an error occurs.

### xmlSecDSigCtxDestroy ()

    void
    xmlSecDSigCtxDestroy (xmlSecDSigCtxPtr dsigCtx);

Destroy context object created with xmlSecDSigCtxCreate function.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |

### xmlSecDSigCtxInitialize ()

    int
    xmlSecDSigCtxInitialize (xmlSecDSigCtxPtr dsigCtx,
                             xmlSecKeysMngrPtr keysMngr);

Initializes <dsig:Signature/> element processing context. The caller is responsible for cleaning up returned object by calling xmlSecDSigCtxFinalize function.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
keysMngr | the pointer to keys manager. |

#### Returns

0 on success or a negative value if an error occurs.

### xmlSecDSigCtxFinalize ()

    void
    xmlSecDSigCtxFinalize (xmlSecDSigCtxPtr dsigCtx);

Cleans up `dsigCtx` object initialized with xmlSecDSigCtxInitialize function.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |

### xmlSecDSigCtxSign ()

    int
    xmlSecDSigCtxSign (xmlSecDSigCtxPtr dsigCtx,
                       xmlNodePtr tmpl);

Signs the data as described in `tmpl` node.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
tmpl | the pointer to <dsig:Signature/> node with signature template. |

#### Returns

0 on success or a negative value if an error occurs.

### xmlSecDSigCtxVerify ()

    int
    xmlSecDSigCtxVerify (xmlSecDSigCtxPtr dsigCtx,
                         xmlNodePtr node);

Validates signature in the `node` . The verification result is returned in status member of the `dsigCtx` object.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
node | the pointer with <dsig:Signature/> node. |

#### Returns

0 on success (check status member of `dsigCtx` to get signature verification result) or a negative value if an error occurs.

### xmlSecDSigCtxEnableReferenceTransform ()

    int
    xmlSecDSigCtxEnableReferenceTransform (xmlSecDSigCtxPtr dsigCtx,
                                           xmlSecTransformId transformId);

Enables `transformId` for <dsig:Reference/> elements processing.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
transformId | the transform klass. |

#### Returns

0 on success or a negative value if an error occurs.

### xmlSecDSigCtxEnableSignatureTransform ()

    int
    xmlSecDSigCtxEnableSignatureTransform (xmlSecDSigCtxPtr dsigCtx,
                                           xmlSecTransformId transformId);

Enables `transformId` for <dsig:SignedInfo/> element processing.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
transformId | the transform klass. |

#### Returns

0 on success or a negative value if an error occurs.

### xmlSecDSigCtxGetPreSignBuffer ()

    xmlSecBufferPtr
    xmlSecDSigCtxGetPreSignBuffer (xmlSecDSigCtxPtr dsigCtx);

Gets pointer to the buffer with serialized <dsig:SignedInfo/> element just before signature claculation (valid if and only if XMLSEC_DSIG_FLAGS_STORE_SIGNATURE context flag is set.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |

#### Returns

0 on success or a negative value if an error occurs.

### xmlSecDSigCtxDebugDump ()

    void
    xmlSecDSigCtxDebugDump (xmlSecDSigCtxPtr dsigCtx,
                            FILE *output);

Prints the debug information about `dsigCtx` to `output` .

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
output | the pointer to output FILE. |

### xmlSecDSigCtxDebugXmlDump ()

    void
    xmlSecDSigCtxDebugXmlDump (xmlSecDSigCtxPtr dsigCtx,
                               FILE *output);

Prints the debug information about `dsigCtx` to `output` in XML format.

#### Parameters

dsigCtx | the pointer to <dsig:Signature/> processing context. |
output | the pointer to output FILE. |

### xmlSecDSigReferenceCtxCreate ()

    xmlSecDSigReferenceCtxPtr
    xmlSecDSigReferenceCtxCreate (xmlSecDSigCtxPtr dsigCtx,
                                  xmlSecDSigReferenceOrigin origin);

Creates new <dsig:Reference/> element processing context. Caller is responsible for destroying the returned context by calling xmlSecDSigReferenceCtxDestroy function.

#### Parameters

dsigCtx | the pointer to parent <dsig:Signature/> node processing context. |
origin | the reference origin (<dsig:SignedInfo/> or <dsig:Manifest/> node). |

#### Returns

pointer to newly created context or NULL if an error occurs.

### xmlSecDSigReferenceCtxDestroy ()

    void
    xmlSecDSigReferenceCtxDestroy (xmlSecDSigReferenceCtxPtr dsigRefCtx);

Destroy context object created with xmlSecDSigReferenceCtxCreate function.

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |

### xmlSecDSigReferenceCtxInitialize ()

    int
    xmlSecDSigReferenceCtxInitialize (xmlSecDSigReferenceCtxPtr dsigRefCtx,
                                      xmlSecDSigCtxPtr dsigCtx,
                                      xmlSecDSigReferenceOrigin origin);

Initializes new <dsig:Reference/> element processing context. Caller is responsible for cleaning up the returned context by calling xmlSecDSigReferenceCtxFinalize function.

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |
dsigCtx | the pointer to parent <dsig:Signature/> node processing context. |
origin | the reference origin (<dsig:SignedInfo/> or <dsig:Manifest/> node). |

#### Returns

0 on succes or aa negative value otherwise.

### xmlSecDSigReferenceCtxFinalize ()

    void
    xmlSecDSigReferenceCtxFinalize (xmlSecDSigReferenceCtxPtr dsigRefCtx);

Cleans up context object created with xmlSecDSigReferenceCtxInitialize function.

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |

### xmlSecDSigReferenceCtxProcessNode ()

    int
    xmlSecDSigReferenceCtxProcessNode (xmlSecDSigReferenceCtxPtr dsigRefCtx,
                                       xmlNodePtr node);

The Reference Element (http://www.w3.org/TR/xmldsig-core/sec-Reference)

Reference is an element that may occur one or more times. It specifies a digest algorithm and digest value, and optionally an identifier of the object being signed, the type of the object, and/or a list of transforms to be applied prior to digesting. The identification (URI) and transforms describe how the digested content (i.e., the input to the digest method) was created. The Type attribute facilitates the processing of referenced data. For example, while this specification makes no requirements over external data, an application may wish to signal that the referent is a Manifest. An optional ID attribute permits a Reference to be referenced from elsewhere.

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |
node | the pointer to <dsig:Reference/> node. |

#### Returns

0 on succes or aa negative value otherwise.

### xmlSecDSigReferenceCtxGetPreDigestBuffer ()

    xmlSecBufferPtr
    xmlSecDSigReferenceCtxGetPreDigestBuffer
                                   (xmlSecDSigReferenceCtxPtr dsigRefCtx);

Gets the results of <dsig:Reference/> node processing just before digesting (valid only if XMLSEC_DSIG_FLAGS_STORE_SIGNEDINFO_REFERENCES or XMLSEC_DSIG_FLAGS_STORE_MANIFEST_REFERENCES flas of signature context is set).

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |

#### Returns

pointer to the buffer or NULL if an error occurs.

### xmlSecDSigReferenceCtxDebugDump ()

    void
    xmlSecDSigReferenceCtxDebugDump (xmlSecDSigReferenceCtxPtr dsigRefCtx,
                                     FILE *output);

Prints debug information about `dsigRefCtx` to `output` .

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |
output | the pointer to output FILE. |

### xmlSecDSigReferenceCtxDebugXmlDump ()

    void
    xmlSecDSigReferenceCtxDebugXmlDump (xmlSecDSigReferenceCtxPtr dsigRefCtx,
                                        FILE *output);

Prints debug information about `dsigRefCtx` to `output` in output format.

#### Parameters

dsigRefCtx | the pointer to <dsig:Reference/> element processing context. |
output | the pointer to output FILE. |

### xmlSecDSigReferenceCtxListGetKlass ()

    xmlSecPtrListId
    xmlSecDSigReferenceCtxListGetKlass (void);

The <dsig:Reference/> element processing contexts list klass.

#### Returns

<dsig:Reference/> element processing context list klass.

## Types and Values

### enum xmlSecDSigStatus

XML Digital signature processing status.

#### Members

xmlSecDSigStatusUnknown | the status is unknown. |
xmlSecDSigStatusSucceeded | the processing succeeded. |
xmlSecDSigStatusInvalid | the processing failed. |

### XMLSEC_DSIG_FLAGS_IGNORE_MANIFESTS

    #define XMLSEC_DSIG_FLAGS_IGNORE_MANIFESTS                      0x00000001

If this flag is set then <dsig:Manifests/> nodes will not be processed.

### XMLSEC_DSIG_FLAGS_STORE_SIGNEDINFO_REFERENCES

    #define XMLSEC_DSIG_FLAGS_STORE_SIGNEDINFO_REFERENCES           0x00000002

If this flag is set then pre-digest buffer for <dsig:Reference/> child of <dsig:KeyInfo/> element will be stored in xmlSecDSigCtx.

### XMLSEC_DSIG_FLAGS_STORE_MANIFEST_REFERENCES

    #define XMLSEC_DSIG_FLAGS_STORE_MANIFEST_REFERENCES             0x00000004

If this flag is set then pre-digest buffer for <dsig:Reference/> child of <dsig:Manifest/> element will be stored in xmlSecDSigCtx.

### XMLSEC_DSIG_FLAGS_STORE_SIGNATURE

    #define XMLSEC_DSIG_FLAGS_STORE_SIGNATURE                       0x00000008

If this flag is set then pre-signature buffer for <dsig:SignedInfo/> element processing will be stored in xmlSecDSigCtx.

### XMLSEC_DSIG_FLAGS_USE_VISA3D_HACK

    #define XMLSEC_DSIG_FLAGS_USE_VISA3D_HACK                       0x00000010

If this flag is set then URI ID references are resolved directly without using XPointers. This allows one to sign/verify Visa3D documents that don't follow XML, XPointer and XML DSig specifications.

### struct xmlSecDSigCtx

    struct xmlSecDSigCtx {
        /* these data user can set before performing the operation */
        void*                       userData;
        unsigned int                flags;
        unsigned int                flags2;
        xmlSecKeyInfoCtx            keyInfoReadCtx;
        xmlSecKeyInfoCtx            keyInfoWriteCtx;
        xmlSecTransformCtx          transformCtx;
        xmlSecTransformUriType      enabledReferenceUris;
        xmlSecPtrListPtr            enabledReferenceTransforms;
        xmlSecTransformCtxPreExecuteCallback referencePreExecuteCallback;
        xmlSecTransformId           defSignMethodId;
        xmlSecTransformId           defC14NMethodId;
        xmlSecTransformId           defDigestMethodId;

        /* these data are returned */
        xmlSecKeyPtr                signKey;
        xmlSecTransformOperation    operation;
        xmlSecBufferPtr             result;
        xmlSecDSigStatus            status;
        xmlSecTransformPtr          signMethod;
        xmlSecTransformPtr          c14nMethod;
        xmlSecTransformPtr          preSignMemBufMethod;
        xmlNodePtr                  signValueNode;
        xmlChar*                    id;
        xmlSecPtrList               signedInfoReferences;
        xmlSecPtrList               manifestReferences;

        /* reserved for future */
        void*                       reserved0;
        void*                       reserved1;
    };

XML DSig processing context.

#### Members

void *`userData`; | the pointer to user data (xmlsec and xmlsec-crypto libraries never touches this). |
unsigned int `flags`; | the XML Digital Signature processing flags. |
unsigned int `flags2`; | the XML Digital Signature processing flags. |
xmlSecKeyInfoCtx `keyInfoReadCtx`; | the reading key context. |
xmlSecKeyInfoCtx `keyInfoWriteCtx`; | the writing key context (not used for signature verification). |
xmlSecTransformCtx `transformCtx`; | the <dsig:SignedInfo/> node processing context. |
xmlSecTransformUriType `enabledReferenceUris`; | the URI types allowed for <dsig:Reference/> node. |
xmlSecPtrListPtr `enabledReferenceTransforms`; | the list of transforms allowed in <dsig:Reference/> node. |
xmlSecTransformCtxPreExecuteCallback `referencePreExecuteCallback`; | the callback for <dsig:Reference/> node processing. |
xmlSecTransformId `defSignMethodId`; | the default signing method klass. |
xmlSecTransformId `defC14NMethodId`; | the default c14n method klass. |
xmlSecTransformId `defDigestMethodId`; | the default digest method klass. |
xmlSecKeyPtr `signKey`; | the signature key; application may set signKey before calling xmlSecDSigCtxSign or xmlSecDSigCtxVerify functions. |
xmlSecTransformOperation `operation`; | the operation: sign or verify. |
xmlSecBufferPtr `result`; | the pointer to signature (not valid for signature verification). |
xmlSecDSigStatus `status`; | the <dsig:Signature/> processing status. |
xmlSecTransformPtr `signMethod`; | the pointer to signature transform. |
xmlSecTransformPtr `c14nMethod`; | the pointer to c14n transform. |
xmlSecTransformPtr `preSignMemBufMethod`; | the pointer to binary buffer right before signature (valid only if XMLSEC_DSIG_FLAGS_STORE_SIGNATURE flag is set). |
xmlNodePtr `signValueNode`; | the pointer to <dsig:SignatureValue/> node. |
xmlChar *`id`; | the pointer to Id attribute of <dsig:Signature/> node. |
xmlSecPtrList `signedInfoReferences`; | the list of references in <dsig:SignedInfo/> node. |
xmlSecPtrList `manifestReferences`; | the list of references in <dsig:Manifest/> nodes. |
void *`reserved0`; | reserved for the future. |
void *`reserved1`; | reserved for the future. |

### enum xmlSecDSigReferenceOrigin

The possible <dsig:Reference/> node locations: in the <dsig:SignedInfo/> node or in the <dsig:Manifest/> node.

#### Members

xmlSecDSigReferenceOriginSignedInfo | reference in <dsig:SignedInfo/> node. |
xmlSecDSigReferenceOriginManifest | reference <dsig:Manifest/> node. |

### struct xmlSecDSigReferenceCtx

    struct xmlSecDSigReferenceCtx {
        void*                       userData;
        xmlSecDSigCtxPtr            dsigCtx;
        xmlSecDSigReferenceOrigin   origin;
        xmlSecTransformCtx          transformCtx;
        xmlSecTransformPtr          digestMethod;

        xmlSecBufferPtr             result;
        xmlSecDSigStatus            status;
        xmlSecTransformPtr          preDigestMemBufMethod;
        xmlChar*                    id;
        xmlChar*                    uri;
        xmlChar*                    type;

         /* reserved for future */
        void*                       reserved0;
        void*                       reserved1;
    };

The <dsig:Reference/> processing context.

#### Members

void *`userData`; | the pointer to user data (xmlsec and xmlsec-crypto libraries never touches this). |
xmlSecDSigCtxPtr `dsigCtx`; | the pointer to "parent" <dsig:Signature/> processing context. |
xmlSecDSigReferenceOrigin `origin`; | the signature origin (<dsig:SignedInfo/> or <dsig:Manifest/>). |
xmlSecTransformCtx `transformCtx`; | the reference processing transforms context. |
xmlSecTransformPtr `digestMethod`; | the pointer to digest transform. |
xmlSecBufferPtr `result`; | the pointer to digest result. |
xmlSecDSigStatus `status`; | the reference processing status. |
xmlSecTransformPtr `preDigestMemBufMethod`; | the pointer to binary buffer right before digest (valid only if either XMLSEC_DSIG_FLAGS_STORE_SIGNEDINFO_REFERENCES or XMLSEC_DSIG_FLAGS_STORE_MANIFEST_REFERENCES flags are set). |
xmlChar *`id`; | the <dsig:Reference/> node ID attribute. |
xmlChar *`uri`; | the <dsig:Reference/> node URI attribute. |
xmlChar *`type`; | the <dsig:Reference/> node Type attribute. |
void *`reserved0`; | reserved for the future. |
void *`reserved1`; | reserved for the future. |

### xmlSecDSigReferenceCtxListId

    #define             xmlSecDSigReferenceCtxListId

The references list klass.