AWS API Gateway - Private Endpoint - message forbidden

Question

I am trying to setup a private AWS API Gateway and connect to it from my laptop. The laptop resides in a network which is AWS Direct Connect'ed to a private VPC. I am using the toy-example "PetStore" API provided by AWS for this purpose.

According to this guide:

• established a API Gateway service endpoint to my VPC (private DNS disabled)
• gave it a security group that allows ALL inbound traffic from the local network (in which my laptop resides)
• created the API Gateway as private API
• updated the resource policy
• deployed the API as stage V1

Assume:

• AWS account number: 123456789012
• AWS region: eu-central-1
• API Gateway ID: abcdefghij
• API Stage: V1
• VPC Endpoint Domanin: vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com
• VPC Endpoint IP: 10.10.10.10

To invoke my API, I call the following cURL command:

curl -v https://vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com/V1/pets -H 'Host: abcdefghij.execute-api.eu-central-1.amazonaws.com' --noproxy "*"

and this is the result:

*   Trying 10.10.10.10...
* TCP_NODELAY set
* Connected to vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com (10.54.251.244) port 443 (#0)
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 1/3)
* schannel: checking server certificate revocation
* schannel: sending initial handshake data: sending 240 bytes...
* schannel: sent initial handshake data: sent 240 bytes
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 2/3)
* schannel: failed to receive handshake, need more data
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 2/3)
* schannel: encrypted data got 4096
* schannel: encrypted data buffer: offset 4096 length 4096
* schannel: encrypted data length: 4000
* schannel: encrypted data buffer: offset 4000 length 4096
* schannel: received incomplete message, need more data
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 2/3)
* schannel: encrypted data got 1024
* schannel: encrypted data buffer: offset 5024 length 5024
* schannel: encrypted data length: 95
* schannel: encrypted data buffer: offset 95 length 5024
* schannel: received incomplete message, need more data
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 2/3)
* schannel: encrypted data got 252
* schannel: encrypted data buffer: offset 347 length 5024
* schannel: sending next handshake data: sending 126 bytes...
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 2/3)
* schannel: encrypted data got 51
* schannel: encrypted data buffer: offset 51 length 5024
* schannel: SSL/TLS handshake complete
* schannel: SSL/TLS connection with vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com port 443 (step 3/3)
* schannel: stored credential handle in session cache
> GET /V1/pets HTTP/1.1
> Host: vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com
> User-Agent: curl/7.55.1
> Accept: */*
>
* schannel: client wants to read 102400 bytes
* schannel: encdata_buffer resized 103424
* schannel: encrypted data buffer: offset 0 length 103424
* schannel: encrypted data got 364
* schannel: encrypted data buffer: offset 364 length 103424
* schannel: decrypted data length: 283
* schannel: decrypted data added: 283
* schannel: decrypted data cached: offset 283 length 102400
* schannel: encrypted data length: 52
* schannel: encrypted data cached: offset 52 length 103424
* schannel: decrypted data length: 23
* schannel: decrypted data added: 23
* schannel: decrypted data cached: offset 306 length 102400
* schannel: encrypted data buffer: offset 0 length 103424
* schannel: decrypted data buffer: offset 306 length 102400
* schannel: schannel_recv cleanup
* schannel: decrypted data returned 306
* schannel: decrypted data buffer: offset 0 length 102400
< HTTP/1.1 403 Forbidden
< Server: Server
< Date: Fri, 25 Oct 2019 11:32:01 GMT
< Content-Type: application/json
< Content-Length: 23
< Connection: keep-alive
< x-amzn-RequestId: a5aa9f76-4e3b-4315-838a-e859fa192ade
< x-amzn-ErrorType: ForbiddenException
< x-amz-apigw-id: jdsak!291kd
<
{"message":"Forbidden"}* Connection #0 to host vpce-1234567890.execute-api.eu-central-1.vpce.amazonaws.com left intact
* Rebuilt URL to: abcdefghij.execute-api.eu-central-1.amazonaws.com'/
* Could not resolve host: abcdefghij.execute-api.eu-central-1.amazonaws.com'
* Closing connection 1
curl: (6) Could not resolve host: abcdefghij.execute-api.eu-central-1.amazonaws.com'

There is this {"message":"Forbidden"} which I am not sure from where it comes. And also the error Could not resolve host: abcdefghij.execute-api.eu-central-1.amazonaws.com.

So my question is: where this issue comes from?

APPENDIX

Resource policy

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": "*",
            "Action": "execute-api:Invoke",
            "Resource": "arn:aws:execute-api:eu-central-1:123456789012:abcdefghij/*"
        }
    ]
}

Answer 1

The previous AWS API gateway private API configuration document is a bit misleading, I had pushed the update for the documentation.

When you create a private API gateway, there are two key fields you should pay attention to:

1. VPC endpoint ID
2. VPC ID

For VPC End Point Configuration under APIs->Your API->Settings:

Endpoint Configuration:
   VPC End Point ID:
       *Your VPC End Point ID(This is the VPC End point ID with     
    com.amazonaws.ap-southeast-1.execute-api permission)

Under APIs->Your API->Resource Policy, configure resource policy:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Deny",
            "Principal": "*",
            "Action": "execute-api:Invoke",
            "Resource": "arn:aws:execute-api:eu-central-1:123456789012:abcdefghij/*",
            "Condition": {
                "StringNotEquals": {
                    "aws:sourceVpc": "Change to your VPC ID"
                }
            }
        },
        {
            "Effect": "Allow",
            "Principal": "*",
            "Action": "execute-api:Invoke",
            "Resource": "arn:aws:execute-api:eu-central-1:123456789012:abcdefghij/*"
        }
    ]
}

Answer 2

I've had a similar issue that was related to Resource policy. try to use the following policy:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": "*",
            "Action": "execute-api:Invoke",
            "Resource": "arn:aws:execute-api:${AWS_REGION}:${AWS_ACCOUNT_ID}:${API_GETWAY_ID}/*/*/*",
            "Condition": {
                "StringNotEquals": {
                    "aws:sourceVpc": "${VPC_ENDPOINT_ID}"
                }
            }
        }
    ]
}

Also, make sure the VPC Endpoint IDs include your vpce: