dialog loading, validation, more logic in forms, IP address banning

database/ipban.go

@@ -0,0 +1,81 @@
+/*
+ * Amsterdam Web Communities System
+ * Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+// The database package contains database management and storage logic.
+package database
+
+import (
+	"fmt"
+	"math/big"
+	"net"
+	"sync"
+	"time"
+)
+
+// low64mask is bigint 0xFFFFFFFFFFFFFFFF, used in splitting large addresses.
+var low64mask *big.Int
+
+// knownBans is a cache of known banned addresses.
+var knownBans map[string]string
+
+// knownGood is a cache of known good IP addresses.
+var knownGood map[string]bool
+
+// banMutex synchronizes access to our cache.
+var banMutex sync.Mutex
+
+// init initializes the internals in this file.
+func init() {
+	a := big.NewInt(1)
+	b := big.NewInt(0).Lsh(a, 64)
+	low64mask = big.NewInt(0).Sub(b, big.NewInt(1))
+	knownBans = make(map[string]string)
+	knownGood = make(map[string]bool)
+}
+
+/* AmTestIPBan tests an IP address to see if it's on the banned list.
+ * Parameters:
+ *     ip_address - The IP address to be tested.
+ * Returns:
+ *     Ban message if the address is banned, or empty string if it isn't.
+ *     Standard Go error status.
+ */
+func AmTestIPBan(ip_address string) (string, error) {
+	banMutex.Lock()
+	defer banMutex.Unlock()
+	rc := knownBans[ip_address]
+	if rc != "" {
+		return rc, nil
+	}
+	if knownGood[ip_address] {
+		return "", nil
+	}
+	addr := net.ParseIP(ip_address)
+	if addr == nil {
+		return "", fmt.Errorf("invalid address %s", ip_address)
+	}
+	iv := big.NewInt(0)
+	iv.SetBytes(addr)
+	iv_lo := big.NewInt(0).And(iv, low64mask).Uint64()
+	iv_hi := big.NewInt(0).Rsh(iv, 64).Uint64()
+	rows, err := amdb.Query(`
+		SELECT message FROM ipban WHERE (address_lo & mask_lo) = (? & mask_lo)
+			AND (address_hi & mask_hi) = (? & mask_hi) AND (expire IS NULL OR expire >= ?)
+			AND enable <> 0 ORDER BY mask_hi DESC, mask_lo DESC`, iv_lo, iv_hi, time.Now())
+	if err != nil {
+		return "", err
+	}
+	defer rows.Close()
+	if rows.Next() {
+		rows.Scan(&rc)
+		knownBans[ip_address] = rc
+		return rc, nil
+	}
+	knownGood[ip_address] = true
+	return "", nil
+}

database/validate.go

@@ -0,0 +1,27 @@
+/*
+ * Amsterdam Web Communities System
+ * Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+// The database package contains database management and storage logic.
+package database
+
+import "strings"
+
+const AMS_ID_CHARS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_~*'$"
+
+// AmIsValidAmsterdamID returns true if the given string is a valid Amsterdam ID.
+func AmIsValidAmsterdamID(test string) bool {
+	if len(test) < 1 {
+		return false
+	}
+	for _, r := range test {
+		if !strings.ContainsRune(AMS_ID_CHARS, r) {
+			return false
+		}
+	}
+	return true
+}

login.go

@@ -9,7 +9,11 @@
 // Package main contains the high-level Amsterdam logic.
 package main
 
-import "git.erbosoft.com/amy/amsterdam/ui"
+import (
+	"fmt"
+
+	"git.erbosoft.com/amy/amsterdam/ui"
+)
 
 /* LoginForm renders the Amsterdam login form.
  * Parameters:
@@ -20,8 +24,20 @@ import "git.erbosoft.com/amy/amsterdam/ui"
  *     Standard Go error status.
  */
 func LoginForm(ctxt ui.AmContext) (string, any, error) {
+	// Get target URI.
+	target := ctxt.Parameter("tgt")
+	if target == "" {
+		target = "/"
+	}
+
+	// If user is already logged in, this is a no-op.
+	if !ctxt.CurrentUser().IsAnon {
+		return "redirect", target, nil
+	}
+
 	dlg, err := ui.AmLoadDialog("login")
 	if err == nil {
+		dlg.Field("tgt").Value = target
 		ctxt.VarMap().Set("amsterdam_pageTitle", "Log In")
 		return dlg.Render(ctxt)
 	}
@@ -37,6 +53,18 @@ func LoginForm(ctxt ui.AmContext) (string, any, error) {
  *     Standard Go error status.
  */
 func NewAccountUserAgreement(ctxt ui.AmContext) (string, any, error) {
+	// Get target URI.
+	target := ctxt.Parameter("tgt")
+	if target == "" {
+		target = "/"
+	}
+
+	// If user is already logged in, this is an error.
+	if !ctxt.CurrentUser().IsAnon {
+		return ui.ErrorPage(ctxt, fmt.Errorf("You cannot create a bew account while logged in on an existing one. You must log out first."))
+	}
+
+	ctxt.VarMap().Set("target", target)
 	ctxt.VarMap().Set("amsterdam_pageTitle", "New Account User Agreement")
 	return "framed_template", "agreement.jet", nil
 }
@@ -50,8 +78,20 @@ func NewAccountUserAgreement(ctxt ui.AmContext) (string, any, error) {
  *     Standard Go error status.
  */
 func NewAccountForm(ctxt ui.AmContext) (string, any, error) {
+	// Get target URI.
+	target := ctxt.Parameter("tgt")
+	if target == "" {
+		target = "/"
+	}
+
+	// If user is already logged in, this is an error.
+	if !ctxt.CurrentUser().IsAnon {
+		return ui.ErrorPage(ctxt, fmt.Errorf("You cannot create a bew account while logged in on an existing one. You must log out first."))
+	}
+
 	dlg, err := ui.AmLoadDialog("newaccount")
 	if err == nil {
+		dlg.Field("tgt").Value = target
 		dlg.Field("country").Value = "XX"
 		ctxt.VarMap().Set("amsterdam_pageTitle", "Create New Account")
 		return dlg.Render(ctxt)

setup/database.sql

@@ -425,14 +425,16 @@ CREATE TABLE imagestore (
 # Table listing IP addresses that are banned from logging in or registering.
 CREATE TABLE ipban (
     id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
-    address BIGINT NOT NULL,
+    address_lo BIGINT UNSIGNED NOT NULL,
-    mask BIGINT NOT NULL,
+    address_hi BIGINT UNSIGNED NOT NULL,
+    mask_lo BIGINT UNSIGNED NOT NULL,
+    mask_hi BIGINT UNSIGNED NOT NULL,
     enable TINYINT NOT NULL DEFAULT 1,
     expire DATETIME,
     message VARCHAR(255) NOT NULL,
     block_by INT NOT NULL,
     block_on DATETIME NOT NULL,
-    INDEX by_mask (mask),
+    INDEX by_mask (mask_hi, mask_lo),
     INDEX by_date (block_on)
 );
 

ui/amcontext.go

@@ -13,6 +13,7 @@ package ui
 import (
 	"bytes"
 	"net/http"
+	"strconv"
 
 	"git.erbosoft.com/amy/amsterdam/database"
 	"github.com/CloudyKit/jet/v6"
@@ -25,8 +26,11 @@ import (
 // AmContext is the interface for Amsterdam's wrapper context that exposes the required functionality.
 type AmContext interface {
 	CurrentUser() *database.User
+	FormField(string) string
+	FormFieldInt(string) (int, error)
 	RC() int
 	OutputType() string
+	Parameter(string) string
 	Render(string) error
 	SubRender(string) ([]byte, error)
 	Session() *sessions.Session
@@ -57,6 +61,27 @@ func (c *amContext) CurrentUser() *database.User {
 	return u
 }
 
+/* FormField returns the value of a form field from the request.
+ * Parameters:
+ *     name - The name of the field to retrieve.
+ * Returns:
+ *     The value given to that named field.
+ */
+func (c *amContext) FormField(name string) string {
+	return c.echoContext.FormValue(name)
+}
+
+/* FormField returns the value of a form field from the request, as an integer.
+ * Parameters:
+ *     name - The name of the field to retrieve.
+ * Returns:
+ *     The value given to that named field.
+ *     Standard Go error status.
+ */
+func (c *amContext) FormFieldInt(name string) (int, error) {
+	return strconv.Atoi(c.echoContext.FormValue(name))
+}
+
 // RC returns the HTTP result code for the current operation.
 func (c *amContext) RC() int {
 	return c.httprc
@@ -67,6 +92,20 @@ func (c *amContext) OutputType() string {
 	return c.outputType
 }
 
+/* Parameter returns the value of a parameter (query parameter or form field) from the request.
+ * Parameters:
+ *     name - The name of the field to retrieve.
+ * Returns:
+ *     The value given to that named field.
+ */
+func (c *amContext) Parameter(name string) string {
+	rc := c.echoContext.QueryParam(name)
+	if rc == "" && c.echoContext.Request().Method == "POST" {
+		rc = c.echoContext.FormValue(name)
+	}
+	return rc
+}
+
 /* Render renders a template to the output. Called at the top level only.
  * Parameters:
  *     name = The name of the tempate to be rendered.

ui/dialog.go

@@ -13,7 +13,9 @@ package ui
 import (
 	"embed"
 	"fmt"
+	"net/mail"
 
+	"git.erbosoft.com/amy/amsterdam/database"
 	"gopkg.in/yaml.v3"
 )
 
@@ -28,6 +30,7 @@ type DialogItem struct {
 	MaxLength  int    `yaml:"maxlength,omitempty"`
 	Value      string `yaml:"value,omitempty"`
 	Param      string `yaml:"param,omitempty"`
+	AuxData    any
 }
 
 // Dialog holds the dialog definition.
@@ -72,6 +75,18 @@ func AmLoadDialog(name string) (*Dialog, error) {
 	return nil, err
 }
 
+// DateValues returns the date values stored in a date field.
+func (fld *DialogItem) DateValues() []int {
+	if fld.Type == "date" && fld.AuxData != nil {
+		return fld.AuxData.([]int)
+	}
+	rc := make([]int, 3)
+	rc[0] = -1
+	rc[1] = -1
+	rc[2] = -1
+	return rc
+}
+
 /* Field returns a pointer to a dialog's field, given its name.
  * Parameters:
  *     name - The name of the field to find.
@@ -107,3 +122,179 @@ func (d *Dialog) Render(ctxt AmContext) (string, any, error) {
 	ctxt.VarMap().Set("amsterdam_dialog", d)
 	return "framed_template", "dialog.jet", nil
 }
+
+/* LoadFromForm loads the values in a dialog from the form fields in the request.
+ * Parameters:
+ *     ctxt - The AmContext for this request.
+ */
+func (d *Dialog) LoadFromForm(ctxt AmContext) {
+	for _, fld := range d.Fields {
+		if fld.Type == "date" {
+			fld.Value = ""
+			dvals := make([]int, 3)
+			var err error
+			dvals[0], err = ctxt.FormFieldInt(fmt.Sprintf("%s_month", fld.Name))
+			if err != nil {
+				dvals[0] = -1
+				fld.Value = fmt.Sprintf("!undefined month %s: %v", fld.Name, err)
+			}
+			dvals[1], err = ctxt.FormFieldInt(fmt.Sprintf("%s_day", fld.Name))
+			if err != nil {
+				dvals[1] = -1
+				if fld.Value == "" {
+					fld.Value = fmt.Sprintf("!undefined day %s: %v", fld.Name, err)
+				}
+			}
+			dvals[2], err = ctxt.FormFieldInt(fmt.Sprintf("%s_year", fld.Name))
+			if err != nil {
+				dvals[2] = -1
+				if fld.Value == "" {
+					fld.Value = fmt.Sprintf("!undefined year %s: %v", fld.Name, err)
+				}
+			}
+			if dvals[0] > 0 && dvals[1] > 0 && dvals[2] > 0 {
+				fld.Value = fmt.Sprintf("%04d%02d%02d", dvals[2], dvals[0], dvals[1])
+			} else if fld.Value == "" && fld.Required {
+				if dvals[0] <= 0 {
+					fld.Value = fmt.Sprintf("!month not set %s", fld.Name)
+				} else if dvals[1] <= 0 {
+					fld.Value = fmt.Sprintf("!day not set %s", fld.Name)
+				} else if dvals[2] <= 0 {
+					fld.Value = fmt.Sprintf("!year not set %s", fld.Name)
+				}
+			}
+			fld.AuxData = dvals
+		} else {
+			fld.Value = ctxt.FormField(fld.Name)
+		}
+	}
+}
+
+// validatorFunc is a function that validates the contents of a dialog item.
+type validatorFunc func(*DialogItem) error
+
+// nilValidator is a validator function that doesn't do anything.
+func nilValidator(*DialogItem) error {
+	return nil
+}
+
+/* validateTextField validates a text field.
+ * Parameters:
+ *     fld - The field to be validated.
+ * Returns:
+ *     Standard Go error status.
+ */
+func validateTextField(fld *DialogItem) error {
+	if len(fld.Value) == 0 && fld.Required {
+		return fmt.Errorf("value of field \"%s\" is required", fld.Caption)
+	}
+	if len(fld.Value) > fld.MaxLength {
+		return fmt.Errorf("value of field \"%s\" can be no longer than %d characters", fld.Caption, fld.MaxLength)
+	}
+	return nil
+}
+
+/* validateAmsIdField validates an Amsterdam ID field.
+ * Parameters:
+ *     fld - The field to be validated.
+ * Returns:
+ *     Standard Go error status.
+ */
+func validateAmsIdField(fld *DialogItem) error {
+	err := validateTextField(fld)
+	if err == nil {
+		if !database.AmIsValidAmsterdamID(fld.Value) {
+			err = fmt.Errorf("value of field \"%s\" is not a valid identifier", fld.Caption)
+		}
+	}
+	return err
+}
+
+/* validateEmailField validates an E-mail address field.
+ * Parameters:
+ *     fld - The field to be validated.
+ * Returns:
+ *     Standard Go error status.
+ */
+func validateEmailField(fld *DialogItem) error {
+	err := validateTextField(fld)
+	if err == nil {
+		_, err = mail.ParseAddress(fld.Value)
+	}
+	return err
+}
+
+/* validateCountryField validates a country code field.
+ * Parameters:
+ *     fld - The field to be validated.
+ * Returns:
+ *     Standard Go error status.
+ */
+func validateCountryField(fld *DialogItem) error {
+	if fld.Value == "XX" && fld.Required {
+		return fmt.Errorf("country field \"%s\" not set", fld.Caption)
+	}
+	return nil
+}
+
+/* validateDateField validates a date field.
+ * Parameters:
+ *     fld - The field to be validated.
+ * Returns:
+ *     Standard Go error status.
+ */
+func validateDateField(fld *DialogItem) error {
+	if len(fld.Value) == 0 && fld.Required {
+		return fmt.Errorf("date value %s not set", fld.Caption)
+	}
+	if fld.Value[0] == '!' {
+		return fmt.Errorf("date value %s erroneous: %s", fld.Caption, fld.Value[1:])
+	}
+	if fld.AuxData == nil {
+		return fmt.Errorf("date value %s not set properly", fld.Caption)
+	}
+	dv := fld.AuxData.([]int)
+	if dv[0] > 12 || dv[1] > 31 {
+		return fmt.Errorf("date value %s malformed", fld.Caption)
+	}
+	q := fmt.Sprintf("%04d%02d%02d", dv[2], dv[0], dv[1])
+	if q != fld.Value {
+		return fmt.Errorf("date value %s should be %s but is %s", fld.Caption, q, fld.Value)
+	}
+	return nil
+}
+
+// validators maps the field types to validator functions.
+var validators = map[string]validatorFunc{
+	"ams_id":      validateAmsIdField,
+	"button":      nilValidator,
+	"checkbox":    nilValidator,
+	"countrylist": validateCountryField,
+	"date":        validateDateField,
+	"email":       validateEmailField,
+	"header":      nilValidator,
+	"hidden":      nilValidator,
+	"password":    validateTextField,
+	"text":        validateTextField,
+}
+
+/* Validate validates the values in the dialog.
+ * Returns:
+ *     Standard Go error status.
+ */
+func (d *Dialog) Validate() error {
+	for _, fld := range d.Fields {
+		if len(fld.Value) > 0 || fld.Required {
+			vfunc := validators[fld.Type]
+			if vfunc != nil {
+				err := vfunc(&fld)
+				if err != nil {
+					return err
+				}
+			} else {
+				return fmt.Errorf("don't know how to validate field %s of type %s", fld.Name, fld.Type)
+			}
+		}
+	}
+	return nil
+}

ui/render_wrap.go

@@ -12,7 +12,9 @@ package ui
 
 import (
 	"fmt"
+	"net/http"
 
+	"git.erbosoft.com/amy/amsterdam/database"
 	"github.com/labstack/echo/v4"
 )
 
@@ -21,6 +23,8 @@ func sendPageData(ctxt echo.Context, amctxt AmContext, command string, data any)
 	switch command {
 	case "bytes":
 		err = ctxt.Blob(amctxt.RC(), amctxt.OutputType(), data.([]byte))
+	case "redirect":
+		err = ctxt.Redirect(http.StatusFound, data.(string))
 	case "string":
 		err = ctxt.String(amctxt.RC(), fmt.Sprintf("%v", data))
 	case "template":
@@ -64,6 +68,15 @@ func AmWrap(myfunc func(AmContext) (string, any, error)) echo.HandlerFunc {
 			ctxt.Logger().Errorf("Session creation error: %v", aerr)
 			return aerr
 		}
+		banmsg, banerr := database.AmTestIPBan(ctxt.RealIP())
+		if banerr != nil {
+			ctxt.Logger().Warnf("address %s could not be tested: %v", ctxt.RealIP(), banerr)
+			// but let the request pass anyway
+		} else if banmsg != "" {
+			amctxt.VarMap().Set("amsterdam_pageTitle", "IP Address Banned")
+			amctxt.VarMap().Set("message", banmsg)
+			return sendPageData(ctxt, amctxt, "framed_template", "ipban.jet")
+		}
 		what, rc, err := myfunc(amctxt)
 		if err == nil {
 			if err = amctxt.Session().Save(ctxt.Request(), ctxt.Response()); err != nil {

ui/views/agreement.jet

@@ -16,7 +16,7 @@
             </p>
             <div class="flex justify-center gap-4 mt-6">
                 <button type="button" class="bg-blue-600 hover:bg-blue-700 text-white px-6 py-2 rounded font-medium transition-colors"
-                        onclick="window.location.assign('/newacct2')">I Accept</button>
+                        onclick="window.location.assign('/newacct2?tgt={{ target | url }}')">I Accept</button>
                 <button type="button" class="bg-red-600 hover:bg-red-700 text-white px-6 py-2 rounded font-medium transition-colors"
                         onclick="window.location.assign('/')">I Decline</button>
             </div>

ui/views/dialog.jet

@@ -80,6 +80,7 @@
                             </select>
                         </div>
                     {{ else if .Type == "date" }}
+                        {{ dv := .DateValues() }}
                         <div class="flex items-center">
                             <label class="w-64 text-right pr-4 text-black text-sm">
                                 {{ .Caption }}{{ if .Subcaption != "" }} {{ .Subcaption }}{{ end }}
@@ -88,21 +89,21 @@
                             <div class="flex gap-2">
                                 <select name="{{ .Name }}_month"
                                         class="px-3 py-2 border border-gray-300 rounded focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500">
-                                    <option value="-1" selected>---</option>
+                                    <option value="-1" {{ if dv[0] == -1 }}selected{{ end }}>---</option>
                                     {{ range i := GetMonthList() }}
-                                        <option value="{{ i + 1 }}">{{ . }}</option>
+                                        <option value="{{ i + 1 }}" {{ if dv[0] == i + 1 }}selected{{ end }}>{{ . }}</option>
                                     {{ end }}
                                 </select>
                                 <select name="{{ .Name }}_day" class="px-3 py-2 border border-gray-300 rounded focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500">
-                                    <option value="-1" selected>---</option>
+                                    <option value="-1" {{ if dv[1] == -1 }}selected{{ end }}>---</option>
                                     {{ range MakeIntRange(1, 32, 1) }}
-                                        <option value="{{ . }}">{{ . }}</option>
+                                        <option value="{{ . }}" {{ if dv[1] == . }}selected{{ end }}>{{ . }}</option>
                                     {{ end }}
                                 </select>
                                 <select name="{{ .Name }}_year" class="px-3 py-2 border border-gray-300 rounded focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500">
-                                    <option value="-1" selected>---</option>
+                                    <option value="-1" {{ if dv[2] == -1 }}selected{{ end }}>---</option>
                                     {{ range MakeYearRange(.Param) }}
-                                        <option value="{{ . }}">{{ . }}</option>
+                                        <option value="{{ . }}" {{ if dv[2] == . }}selected{{ end }}>{{ . }}</option>
                                     {{ end }}
                                 </select>
                             </div>

ui/views/ipban.jet

@@ -0,0 +1,17 @@
+{*
+ * Amsterdam Web Communities System
+ * Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ *}
+<div class="flex">
+    <div class="flex-1 p-4">
+        <div class="mb-8">
+            <h1 class="text-blue-800 text-4xl font-bold mb-2">This IP Address Has Been Banned</h1>
+            <hr class="border-2 border-gray-400 w-4/5 mb-4">
+            <p class="text-black text-sm mb-4"><strong>{{ message }}</strong></p>
+        </div>
+    </div>
+</div>