Enhance audit logging with extra data (#70)

<!--- Provide a general summary of your changes in the Title above -->

## Description

Enhance audit logging by including request details and IP addresses in
audit entries

## Motivation and Context

<!--- Why is this change required? What problem does it solve? -->
<!--- If it fixes an open issue, please link to the issue here. -->

## How Has This Been Tested?

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to -->
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## Checklist:

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that apply. -->
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- [ ] My change requires a change to the documentation or CHANGELOG.
- [ ] I have updated the documentation/CHANGELOG accordingly.
- [ ] I have created a feature (non-master) branch for my PR.

oauthproxy.go

@@ -827,14 +827,14 @@ func (p *OAuthProxy) backendLogout(rw http.ResponseWriter, req *http.Request, si
 		if resp.StatusCode() != 200 {
 			logger.Errorf("error while calling backend logout url, returned error code %v", resp.StatusCode())
 		}
-		p.picsAuditClient.CreateSuccessfulLogoutAuditEntry(session, req.RequestURI, req.Header.Get("edisp-org-id"))
+		p.picsAuditClient.CreateSuccessfulLogoutAuditEntry(session, req.RequestURI, req.Header.Get("edisp-org-id"), req)
 	} else {
 		if providerData.BackendRevokeAccessTokenURL != "" {
 			err := PicsRevokeAccessToken(providerData.BackendRevokeAccessTokenURL, session.AccessToken, providerData.ClientID, providerData.ClientSecret)
 			if err != nil {
 				logger.Errorf("error while calling backend revoke access token: %v", err)
 			} else {
-				p.picsAuditClient.CreateSuccessfulRevokeAccessTokenAuditEntry(session, req.RequestURI, req.Header.Get("edisp-org-id"))
+				p.picsAuditClient.CreateSuccessfulRevokeAccessTokenAuditEntry(session, req.RequestURI, req.Header.Get("edisp-org-id"), req)
 			}
 		}
 
@@ -1010,7 +1010,7 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {
 			p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 			return
 		}
-		p.picsAuditClient.CreateSuccessfulLoginAuditEntry(session, appRedirect, req.Header.Get("edisp-org-id"))
+		p.picsAuditClient.CreateSuccessfulLoginAuditEntry(session, appRedirect, req.Header.Get("edisp-org-id"), req)
 		http.Redirect(rw, req, appRedirect, http.StatusFound)
 	} else {
 		logger.PrintAuthf(session.Email, req, logger.AuthFailure, "Invalid authentication via OAuth2: unauthorized")

pkg/pics/audit/audit_client.go

@@ -5,6 +5,9 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"net"
+	"net/http"
+	"os"
 	"strings"
 	"time"
 
@@ -52,34 +55,60 @@ func NewAuditClient(opts *ClientOpts) (*Client, error) {
 	return &Client{enabled: opts.Enabled, apiSignature: apiSignature, client: client, opts: opts}, nil
 }
 
-func (c *Client) CreateSuccessfulLoginAuditEntry(ss *sessions.SessionState, appURL string, tenantID string) {
+func (c *Client) CreateSuccessfulLoginAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, req *http.Request) {
 	coding := Coding{
 		System: "http://hl7.org/fhir/ValueSet/audit-event-type", Version: "1", Code: "110114", Display: "User Authentication"}
-	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding)
+	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding, req)
 }
 
-func (c *Client) CreateFailedLoginAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, errorDesc string) {
+func (c *Client) CreateFailedLoginAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, errorDesc string, req *http.Request) {
 	coding := Coding{
 		System: "http://hl7.org/fhir/ValueSet/audit-event-type", Version: "1", Code: "110114", Display: "User Authentication"}
-	c.createAuditEntry(ss, appURL, tenantID, "1", errorDesc, &coding)
+	c.createAuditEntry(ss, appURL, tenantID, "1", errorDesc, &coding, req)
 }
 
-func (c *Client) CreateSuccessfulLogoutAuditEntry(ss *sessions.SessionState, appURL string, tenantID string) {
+func (c *Client) CreateSuccessfulLogoutAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, req *http.Request) {
 	coding := Coding{
 		System: "http://hl7.org/fhir/ValueSet/audit-event-type", Version: "1", Code: "110123", Display: "User Logout All Sessions"}
-	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding)
+	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding, req)
 }
 
-func (c *Client) CreateSuccessfulRevokeAccessTokenAuditEntry(ss *sessions.SessionState, appURL string, tenantID string) {
+func (c *Client) CreateSuccessfulRevokeAccessTokenAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, req *http.Request) {
 	coding := Coding{
 		System: "http://hl7.org/fhir/ValueSet/audit-event-type", Version: "1", Code: "110123", Display: "User revoked access token"}
-	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding)
+	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding, req)
 }
 
-func (c *Client) createAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, outcomeCode string, outcomeDesc string, coding *Coding) {
+func (c *Client) createAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, outcomeCode string, outcomeDesc string, coding *Coding, req *http.Request) {
 	if !c.enabled {
 		return
 	}
+
+	// Service/component identifier
+	serviceIDs := []string{"oauth2proxy"}
+	var targetIP string
+	if hn, err := os.Hostname(); err == nil {
+		serviceIDs = append(serviceIDs, hn)
+		addrs, err := net.LookupHost(hn)
+		if err == nil && len(addrs) > 0 {
+			targetIP = addrs[0]
+		} else {
+			targetIP = hn
+		}
+	} else {
+		targetIP = "unknown"
+	}
+
+	// Extract source IP address
+	sourceIP := ""
+	if req != nil {
+		sourceIP = req.RemoteAddr
+		if xff := req.Header.Get("X-Forwarded-For"); xff != "" {
+			ips := strings.Split(xff, ",")
+			sourceIP = strings.TrimSpace(ips[0])
+		}
+	}
+
 	auditObject := RootEvent{
 		ResourceType: "AuditEvent",
 		Event: &Event{
@@ -88,7 +117,6 @@ func (c *Client) createAuditEntry(ss *sessions.SessionState, appURL string, tena
 			DateTime:    time.Now().UTC().Format(time.RFC3339),
 			Outcome:     outcomeCode,
 			OutcomeDesc: outcomeDesc},
-
 		Participant: []*Participant{
 			{AltID: ss.User, UserID: UserID{Value: ss.Email}, Name: ss.PreferredUsername, Requestor: true}},
 		Source: Source{
@@ -133,6 +161,9 @@ func (c *Client) createAuditEntry(ss *sessions.SessionState, appURL string, tena
 				},
 			},
 		},
+		ServiceIDs:      serviceIDs,
+		SourceIPAddress: sourceIP,
+		TargetIPAddress: targetIP,
 	}
 
 	auditMessage, err := json.Marshal(auditObject)

pkg/pics/audit/audit_event.go

@@ -115,4 +115,7 @@ type RootEvent struct {
 	Participant     []*Participant `json:"participant,omitempty"`
 	Source          Source         `json:"source,omitempty"`
 	Object          []*Object      `json:"object,omitempty"`
+	ServiceIDs      []string       `json:"service_ids,omitempty"`
+	SourceIPAddress string         `json:"source_ip_address,omitempty"`
+	TargetIPAddress string         `json:"target_ip_address,omitempty"`
 }