AuthAws C Reference Documentation
AuthAws
Current Version: 10.1.2
Implements AWS Signature V4 for signing and authenticating AWS REST requests.
Create/Dispose
HCkAuthAws instance = CkAuthAws_Create(); // ... CkAuthAws_Dispose(instance);
Creates an instance of the HCkAuthAws object and returns a handle ("void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkAuthAws_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkAuthAws_Dispose.
Properties
AccessKey
void CkAuthAws_putAccessKey(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_accessKey(HCkAuthAws cHandle);
The AWS access key.
topCanonicalizedResourceV2
void CkAuthAws_putCanonicalizedResourceV2(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_canonicalizedResourceV2(HCkAuthAws cHandle);
If AWS Signature Version V2 is used, then this property must be set. The rules for setting the canonicalized resource for the V2 signature method is described here: Constructing the CanonicalizedResource Element.
DebugLogFilePath
void CkAuthAws_putDebugLogFilePath(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_debugLogFilePath(HCkAuthAws cHandle);
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
LastErrorHtml
const char *CkAuthAws_lastErrorHtml(HCkAuthAws cHandle);
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
const char *CkAuthAws_lastErrorText(HCkAuthAws cHandle);
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
const char *CkAuthAws_lastErrorXml(HCkAuthAws cHandle);
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
void CkAuthAws_putLastMethodSuccess(HCkAuthAws cHandle, BOOL newVal);
Indicates the success or failure of the most recent method call: TRUE means success, FALSE means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.
topPrecomputedMd5
void CkAuthAws_putPrecomputedMd5(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_precomputedMd5(HCkAuthAws cHandle);
This property can optionally be set for AWS requests that have a non-empty request body. This should be the base64 encoding of the 16 bytes of the MD5 hash. The most common need for this is if doing an S3 upload from a stream. (If the pre-computed MD5 is not provided, then Chilkat is forced to stream the entire file into memory so that it can calculate the MD5 for authentication.)
Note: AWS Signature Version 2 uses the MD5, whereas Signature Version 4 uses SHA256.
topPrecomputedSha256
void CkAuthAws_putPrecomputedSha256(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_precomputedSha256(HCkAuthAws cHandle);
This property can optionally be set for AWS requests that have a non-empty request body. This should be the lowercase hex encoding of the 32-bytes of the SHA256 hash. The most common need for this is if doing an S3 upload from a stream. (If the pre-computed SHA-256 is not provided, then Chilkat is forced to stream the entire file into memory so that it can calculate the SHA-256 for authentication.)
Note: AWS Signature Version 4 uses the SHA256 hash. (AWS Signature Version 2 uses MD5)
Region
void CkAuthAws_putRegion(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_region(HCkAuthAws cHandle);
The AWS region, such as "us-east-1", "us-west-2", "eu-west-1", "eu-central-1", etc. The default is "us-east-1". It is only used when the SignatureVersion property is set to 4. This property is unused when the SignatureVersion property is set to 2.
topSecretKey
void CkAuthAws_putSecretKey(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_secretKey(HCkAuthAws cHandle);
The AWS secret key.
topServiceName
void CkAuthAws_putServiceName(HCkAuthAws cHandle, const char *newVal);
const char *CkAuthAws_serviceName(HCkAuthAws cHandle);
The AWS service namespace, such as "s3", "ses", etc. See http://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html#genref-aws-service-namespaces
This property is unused when the SignatureVersion property is set to 2.
topSignatureVersion
void CkAuthAws_putSignatureVersion(HCkAuthAws cHandle, int newVal);
The AWS Signature Version to be used in authentication. The default value is 4. This can optionally be set to the value 2 to use the older V2 signature version.
topUtf8
void CkAuthAws_putUtf8(HCkAuthAws cHandle, BOOL newVal);
When set to TRUE, all "const char *" arguments are interpreted as utf-8 strings. If set to FALSE (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to TRUE, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to FALSE, all "const char *" return values are ANSI strings.
topVerboseLogging
void CkAuthAws_putVerboseLogging(HCkAuthAws cHandle, BOOL newVal);
If set to TRUE, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is FALSE. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
topVersion
const char *CkAuthAws_version(HCkAuthAws cHandle);
Methods
GenPresignedUrl
const char *CkAuthAws_genPresignedUrl(HCkAuthAws cHandle, const char *httpVerb, BOOL useHttps, const char *domain, const char *path, int numSecondsValid, const char *awsService);
Generates a temporary pre-signed URL for an Amazon AWS service using AWS Signature V4. Requires that the SecretKey, AccessKey, and Region properties be set to valid values prior to calling this method.
The URL that is generated has this format:
https://<domain>/<path> ?X-Amz-Algorithm=AWS4-HMAC-SHA256 &X-Amz-Credential=<AccessKey>/<currentDate>/<Region>/<awsService>/aws4_request &X-Amz-Date=<currentDateTime> &X-Amz-Expires=<numSecondsValid> &X-Amz-SignedHeaders=host &X-Amz-Signature=<signature-value>
The httpVerb is the HTTP verb such as "GET", "PUT", "POST", "DELETE", etc. The awsService is a string naming the AWS service, such as "s3", "execute-api", etc. If useHttps is TRUE, then the returned URL begins with "https://", otherwise it begins with "http://".
Returns TRUE for success, FALSE for failure.
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